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Sample records for rc6 rijndael serpent

  1. Evaluating the Performance of Rijndael Encryption

    Directory of Open Access Journals (Sweden)

    Bogdan CIOBANU

    2012-01-01

    Full Text Available In this paper we present a a comparative analysis of the performance of the Rijndael algorithm, developed with the help of two programming languages, namely C and Matlab. The main goal is to get a full, detailed picture about the functioning of this algorithm. In order to evaluate the performances of the Rijndael algorithm for the two different implementations, we took into account establishing the variable factors within each type of implementation so as to avoid the reasons that might lead to running differences (for instance, the comparison of the two implementations will be performed for the situation in which the encryption key length is the same. We chose to use the traditional algorithm for both types of implementation, in which the input is transformed into 4 blocks of 4 bytes, followed by the handling of each byte from each individual column

  2. Improved Impossible Differential Attacks on Large-Block Rijndael

    DEFF Research Database (Denmark)

    Wang, Qingju; Gu, Dawu; Rijmen, Vincent

    2012-01-01

    . The improvement can lead to 10-round attack on Rijndael-256 as well. With 2198.1 chosen plaintexts, an attack is demonstrated on 9-round Rijndael-224 with 2 195.2 encryptions and 2140.4 bytes memory. Increasing the data complexity to 2216 plaintexts, the time complexity can be reduced to 2130 encryptions...... and the memory requirements to 2 93.6 bytes. For 9-round Rijndael-256, we provide an attack requiring 2229.3 chosen plaintexts, 2194 encryptions, and 2 139.6 bytes memory. Alternatively, with 2245.3 plaintexts, an attack with a reduced time of 2127.1 encryptions and a memory complexity of 290.9 bytes can...... be mounted. With 2244.2 chosen plaintexts, we can attack 10-round Rijndael-256 with 2253.9 encryptions and 2186.8 bytes of memory....

  3. 3-D Image Encryption Based on Rubik's Cube and RC6 Algorithm

    Science.gov (United States)

    Helmy, Mai; El-Rabaie, El-Sayed M.; Eldokany, Ibrahim M.; El-Samie, Fathi E. Abd

    2017-12-01

    A novel encryption algorithm based on the 3-D Rubik's cube is proposed in this paper to achieve 3D encryption of a group of images. This proposed encryption algorithm begins with RC6 as a first step for encrypting multiple images, separately. After that, the obtained encrypted images are further encrypted with the 3-D Rubik's cube. The RC6 encrypted images are used as the faces of the Rubik's cube. From the concepts of image encryption, the RC6 algorithm adds a degree of diffusion, while the Rubik's cube algorithm adds a degree of permutation. The simulation results demonstrate that the proposed encryption algorithm is efficient, and it exhibits strong robustness and security. The encrypted images are further transmitted over wireless Orthogonal Frequency Division Multiplexing (OFDM) system and decrypted at the receiver side. Evaluation of the quality of the decrypted images at the receiver side reveals good results.

  4. Implementation of RC5 and RC6 block ciphers on digital images

    International Nuclear Information System (INIS)

    Belhaj Mohamed, A.; Zaibi, G.; Kachouri, A.

    2011-01-01

    With the fast evolution of the networks technology, the security becomes an important research axis. Many types of communication require the transmission of digital images. This transmission must be safe especially in applications that require a fairly high level of security such as military applications, spying, radars, and biometrics applications. Mechanisms for authentication, confidentiality, and integrity must be implemented within their community. For this reason, several cryptographic algorithms have been developed to ensure the safety and reliability of this transmission. In this paper, we investigate the encryption efficiency of RC5 and RC6 block cipher applied to digital images by including a statistical and differential analysis then, and also we investigate those two block ciphers against errors in ambient noise. The security analysis shows that RC6 algorithm is more secure than RC5. However, using RC6 to encrypt images in rough environment (low signal to noise ratio) leads to more errors (almost double of RC5) and may increase energy consumption by retransmitting erroneous packets. A compromise security/energy must be taken into account for the good choice of encryption algorithm.

  5. Derivation of the human embryonic stem cell line RCe010-A (RC-6

    Directory of Open Access Journals (Sweden)

    P.A. De Sousa

    2016-03-01

    Full Text Available The human embryonic stem cell line RCe010-A (RC-6 was derived from a frozen and thawed blastocyst voluntarily donated as unsuitable and surplus to fertility requirements following ethics committee approved informed consent under licence from the UK Human Fertilisation and Embryology Authority. The cell line shows normal pluripotency marker expression and differentiation to the three germ layers in vitro. It has a normal 46XY male karyotype and microsatellite PCR identity, HLA and blood group typing data are available.

  6. APLIKASI ENKRIPSI DAN DEKRIPSI FILE DENGAN MENGGUNAKAN AES (ADVANCED ENCRYPTION STANDARD ALGORITMA RIJNDAEL PADA SISTEM OPERASI ANDROID

    Directory of Open Access Journals (Sweden)

    Langit Da Silva

    2015-04-01

    Full Text Available Rijndael algorithm is an algorithm that won the contest organized by NIST to replace DES algorithm known weaknesses . After winning the contest Rijndael algorithm , Rijndael lagoitma then serve as the AES ( Advanced Encryption Standard . This algorithm has been widely used in the encryption problem both for text , files , and databases . While Android is an open source operating system developed by Google . Currently Android operating system has become the operating system most widely used on smartphoanes . Smartphones now prevalent and had also been owned by many people because of its reliability. In this final project has been able to be made to solve the problem of software security file on the device that uses the Android operating system using AES ( Advanced Encryption Standard Rijndael algorithm . The method used in the design and manufacture of this software is the method GRAPPLE ( Guideliness for Rapid Application Engineering . The programming language used is Java . In the application can generate an encrypted file that can not be opened . To open the file , then the application can perform the decryption process . The parameters used in the analysis of this algorithm when used for encryption and decryption .

  7. Implementasi Aplikasi Kriptografi Pada Layanan Pesan Singkat (SMS Menggunakan Algoritma RC6 Berbasis Android

    Directory of Open Access Journals (Sweden)

    Widi Puji Atmojo

    2016-08-01

    Full Text Available Security is a very important aspect in data communication. In the last decade, there was a rapid development in mobile phone technology. Smartphone have been equipped with various features and one of them is the short message service (SMS. However, messages sent via mobile phone networks pose threat to be accessed by people who do not have any authorization. Therefore, it is necessary to do research on the development of software to enhance the security of messages through message encryption and decryption features. This application uses Java programming language with SDK (Software Development Kit Android and Android Studio 1.3.1 as an editor. The initial step of this research is to encrypt the original message to produce the ciphertext message. The second step is to decrypt ciphertext incoming messages to become genuine message. Results from this research are an Android-based application that can perform encryption and decryption of the SMS messages using the RC6 algorithm. With the application of cryptography for SMS messages, the expected level of information security of the message can be improved so that the message will be more secure from unauthorized access.

  8. Religious Serpent Handling and Community Relations.

    Science.gov (United States)

    Williamson, W Paul; Hood, Ralph W

    2015-01-01

    Christian serpent handling sects of Appalachia comprise a community that has long been mischaracterized and marginalized by the larger communities surrounding them. To explore this dynamic, this article traces the emergence of serpent handling in Appalachia and the emergence of anti-serpent-handling state laws, which eventually failed to curb the practice, as local communities gave serpent handling groups support. We present two studies to consider for improving community relations with serpent handling sects. In study 1, we present data relating the incidence of reported serpent-bite deaths with the rise of anti-serpent-handling laws and their eventual abatement, based on increasing acceptance of serpent handlers by the larger community. Study 2 presents interview data on serpent bites and death that provide explanations for these events from the cultural and religious perspective. We conclude that first-hand knowledge about serpent handlers, and other marginalized groups, helps to lessen suspicion and allows them to be seen as not much different, which are tendencies that are important for promoting inter-community harmony.

  9. Agathos Daimon and the Asklepian serpent.

    Science.gov (United States)

    Pearn, John

    2011-06-01

    Much conjecture abounds about the origin of the Asklepian serpent of healing, this latter the universal metonym for curative medicine. Iconographic evidence of Asklepios with his staff-entwined serpent exists from Hippocratic times. Many theories exist about the origin of this reptilian symbol of curative medicine. Speculation has ranged from the skin-shed serpent emergent in new and robust health to putative associations with earlier Egyptian and Babylonian anguine (snake) symbols of life-determining power. Other scholars have drawn attention to the Palaeolithic, Neolithic and later Bronze-Age associations with serpent veneration in the context of rain and fertility religious invocations in India; and in many other cultures. In the South Pacific, in Australia and in Central and South America, serpents were regarded as spirits of the earth, often chthonian spirits who possessed life-giving powers. In Chaldean and Arabic etymology, the words for "serpent" and "life" have a synergy. In Classical Greece, the Agathos Daimon was literally the "noble spirit", a personal companion spirit ensuing health and good fortune. The Agathos Daimon was portrayed in iconography as a serpent, or as a fit and comely youth. This paper conjectures that the serpentine Agathos Daimon was one origin of the Asklepian symbol of medicine, portrayed as the serpent associated of the Homeric Asklepios. In later Roman times, the Agathos Daimon was transliterated to the agathodaemon, a protective companion spirit both of individuals and of the homes in which they lived. This benign resident spirit featured prominently in Roman art and was a common feature as a protective household spirit in first century homes at both Pompeii and Herculaneum. The agathodaemon motif also featured on Roman coins, such as bronze diobols of Antoninus Plus (138 - 161 A.D.) from Alexandrian mints in Egypt. In the twenty-first century, the serpentine Agathos Daimon is honoured not only as the symbol of medicine; but is

  10. SERPENT Monte Carlo reactor physics code

    International Nuclear Information System (INIS)

    Leppaenen, J.

    2010-01-01

    SERPENT is a three-dimensional continuous-energy Monte Carlo reactor physics burnup calculation code, developed at VTT Technical Research Centre of Finland since 2004. The code is specialized in lattice physics applications, but the universe-based geometry description allows transport simulation to be carried out in complicated three-dimensional geometries as well. The suggested applications of SERPENT include generation of homogenized multi-group constants for deterministic reactor simulator calculations, fuel cycle studies involving detailed assembly-level burnup calculations, validation of deterministic lattice transport codes, research reactor applications, educational purposes and demonstration of reactor physics phenomena. The Serpent code has been publicly distributed by the OECD/NEA Data Bank since May 2009 and RSICC in the U. S. since March 2010. The code is being used in some 35 organizations in 20 countries around the world. This paper presents an overview of the methods and capabilities of the Serpent code, with examples in the modelling of WWER-440 reactor physics. (Author)

  11. Trichomoniasis in Bothrops jararaca (serpentes, viperidae

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    F. C. Vilela

    2003-01-01

    Full Text Available We describe a case of trichomoniasis in a Bothrops jararaca (Serpentes, Viperidae donated to the Center for the Study of Venoms and Venomous Animals - CEVAP/UNESP. The animal had diarrhea with great quantity of flagellated protozoa in the feces. Microscopic examination of fecal smears stained with Giemsa revealed the presence of trichomonads, morphologically similar to Trichomonas acosta. Trichomonads were not detected in fecal exams after treatment with a single dose of 40 mg/kg metronidazole (Flagyl®.

  12. O mito da serpente em D. H. Lawrence = The serpent myth in D. H. Lawrence

    Directory of Open Access Journals (Sweden)

    Ana Maria Leal Cardoso

    2008-01-01

    Full Text Available Este trabalho propõe um estudo do mito da serpente, na obra A serpenteemplumada, de D. H. Lawrence, baseado na trajetória mítica do herói, estabelecida por Joseph Campbell e na crítica junguiana da cultura. Kate, a protagonista, empreende uma busca de renascimento psicológico e espiritual, ao chegar à terra primitiva do México. Tal busca simboliza um retorno ao mundo primitivo da Grande Mãe, entendido, do ponto de vista psicológico, como o inconsciente. Assim como o processo de individuação, descrito por Jung, essa personagem enfrenta rompimentos e dificuldades no decorrer da expansão da consciência. Neste sentido, a serpente simboliza tanto o que é viperino na natureza humana, quanto à sabedoria do corpo e dos instintos.This paper proposes a study on the myth of the serpent in D. H. Lawrence’s The Plumed Serpent, based on Joseph Campbell’s mythical map of the hero’s journey and Jungian criticism. Kate, the femaleprotagonist, embarks on a quest for spiritual-psychological rebirth in the primitive lands of Mexico. Following the pattern of Jung’s individuation process and exploring many recurrent symbols in the narrative, we intend to show how Kate faces ruptures anduncertainties as her consciousness is getting into a process of expansion. According to our analysis, the serpent illustrates the Self’s paradoxical aspect, representing both the viper sideof the human being as well as its knowledge.

  13. Burnup calculation methodology in the serpent 2 Monte Carlo code

    International Nuclear Information System (INIS)

    Leppaenen, J.; Isotalo, A.

    2012-01-01

    This paper presents two topics related to the burnup calculation capabilities in the Serpent 2 Monte Carlo code: advanced time-integration methods and improved memory management, accomplished by the use of different optimization modes. The development of the introduced methods is an important part of re-writing the Serpent source code, carried out for the purpose of extending the burnup calculation capabilities from 2D assembly-level calculations to large 3D reactor-scale problems. The progress is demonstrated by repeating a PWR test case, originally carried out in 2009 for the validation of the newly-implemented burnup calculation routines in Serpent 1. (authors)

  14. Integration of OpenMC methods into MAMMOTH and Serpent

    Energy Technology Data Exchange (ETDEWEB)

    Kerby, Leslie [Idaho National Lab. (INL), Idaho Falls, ID (United States); Idaho State Univ., Idaho Falls, ID (United States); DeHart, Mark [Idaho National Lab. (INL), Idaho Falls, ID (United States); Tumulak, Aaron [Idaho National Lab. (INL), Idaho Falls, ID (United States); Univ. of Michigan, Ann Arbor, MI (United States)

    2016-09-01

    OpenMC, a Monte Carlo particle transport simulation code focused on neutron criticality calculations, contains several methods we wish to emulate in MAMMOTH and Serpent. First, research coupling OpenMC and the Multiphysics Object-Oriented Simulation Environment (MOOSE) has shown promising results. Second, the utilization of Functional Expansion Tallies (FETs) allows for a more efficient passing of multiphysics data between OpenMC and MOOSE. Both of these capabilities have been preliminarily implemented into Serpent. Results are discussed and future work recommended.

  15. The Legends of the Serpent Island in the Danube Delta

    Directory of Open Access Journals (Sweden)

    Tetyana Shevchuk

    2015-08-01

    Full Text Available The report presents a variety of ancient legends, connected with the cult of Achilles on the Serpent (Snake Island, located in 35 km far from the Danube Delta in the territorial waters of Ukraine. The sources of ancient legends are the essay of Flavius Arrian “Periplus Ponti Euxini (maritime guide”, Flavius Philostratus dialogue “On Heroes” (Heroikos, as well as the outlines of Arctinus of Miletus, Maximus of Tyre and Romanian folklore. The imageries of Achilles Pontarchis cult on the Serpent Island (in ancient times – Levka Island, White Island, Island of the Blessed, Fidonisi, Ilan-Ada, Sherpilor disclose the peculiarities of his worship in Scythia and Dacia.

  16. Status Report on the First Round of the Development of the Advanced Encryption Standard

    Science.gov (United States)

    Nechvatal, James; Barker, Elaine; Dodson, Donna; Dworkin, Morris; Foti, James; Roback, Edward

    1999-01-01

    In 1997, the National Institute of Standards and Technology (NIST) initiated a process to select a symmetric-key encryption algorithm to be used to protect sensitive (unclassified) Federal information in furtherance of NIST’s statutory responsibilities. In 1998, NIST announced the acceptance of 15 candidate algorithms and requested the assistance of the cryptographic research community in analyzing the candidates. This analysis included an initial examination of the security and efficiency characteristics for each algorithm. NIST has reviewed the results of this research and selected five algorithms (MARS, RC6™, Rijndael, Serpent and Twofish) as finalists. The research results and rationale for the selection of the finalists are documented in this report. The five finalists will be the subject of further study before the selection of one or more of these algorithms for inclusion in the Advanced Encryption Standard.

  17. Envenimation mortelle par morsure de serpent chez une femme ...

    African Journals Online (AJOL)

    Les auteurs rapportent un cas de morsure de serpent au niveau de la face chez une femme enceinte, dont l'évolution a été marquée par l'installation d'un oedème cervico-facial nécessitant une trachéotomie en urgence, et une mort foetale in utero avec troubles de l'hémostase responsable du décès maternel dans un ...

  18. On the use of the Serpent Monte Carlo code for few-group cross section generation

    International Nuclear Information System (INIS)

    Fridman, E.; Leppaenen, J.

    2011-01-01

    Research highlights: → B1 methodology was used for generation of leakage-corrected few-group cross sections in the Serpent Monte-Carlo code. → Few-group constants generated by Serpent were compared with those calculated by Helios deterministic lattice transport code. → 3D analysis of a PWR core was performed by a nodal diffusion code DYN3D employing two-group cross section sets generated by Serpent and Helios. → An excellent agreement in the results of 3D core calculations obtained with Helios and Serpent generated cross-section libraries was observed. - Abstract: Serpent is a recently developed 3D continuous-energy Monte Carlo (MC) reactor physics burnup calculation code. Serpent is specifically designed for lattice physics applications including generation of homogenized few-group constants for full-core core simulators. Currently in Serpent, the few-group constants are obtained from the infinite-lattice calculations with zero neutron current at the outer boundary. In this study, in order to account for the non-physical infinite-lattice approximation, B1 methodology, routinely used by deterministic lattice transport codes, was considered for generation of leakage-corrected few-group cross sections in the Serpent code. A preliminary assessment of the applicability of the B1 methodology for generation of few-group constants in the Serpent code was carried out according to the following steps. Initially, the two-group constants generated by Serpent were compared with those calculated by Helios deterministic lattice transport code. Then, a 3D analysis of a Pressurized Water Reactor (PWR) core was performed by the nodal diffusion code DYN3D employing two-group cross section sets generated by Serpent and Helios. At this stage thermal-hydraulic (T-H) feedback was neglected. The DYN3D results were compared with those obtained from the 3D full core Serpent MC calculations. Finally, the full core DYN3D calculations were repeated taking into account T-H feedback and

  19. MONTE CARLO ANALYSES OF THE YALINA THERMAL FACILITY WITH SERPENT STEREOLITHOGRAPHY GEOMETRY MODEL

    Energy Technology Data Exchange (ETDEWEB)

    Talamo, A.; Gohar, Y.

    2015-01-01

    This paper analyzes the YALINA Thermal subcritical assembly of Belarus using two different Monte Carlo transport programs, SERPENT and MCNP. The MCNP model is based on combinatorial geometry and universes hierarchy, while the SERPENT model is based on Stereolithography geometry. The latter consists of unstructured triangulated surfaces defined by the normal and vertices. This geometry format is used by 3D printers and it has been created by: the CUBIT software, MATLAB scripts, and C coding. All the Monte Carlo simulations have been performed using the ENDF/B-VII.0 nuclear data library. Both MCNP and SERPENT share the same geometry specifications, which describe the facility details without using any material homogenization. Three different configurations have been studied with different number of fuel rods. The three fuel configurations use 216, 245, or 280 fuel rods, respectively. The numerical simulations show that the agreement between SERPENT and MCNP results is within few tens of pcms.

  20. OPAL reactor calculations using the Monte Carlo code serpent

    Energy Technology Data Exchange (ETDEWEB)

    Ferraro, Diego; Villarino, Eduardo [Nuclear Engineering Dept., INVAP S.E., Rio Negro (Argentina)

    2012-03-15

    In the present work the Monte Carlo cell code developed by VTT Serpent v1.1.14 is used to model the MTR fuel assemblies (FA) and control rods (CR) from OPAL (Open Pool Australian Light-water) reactor in order to obtain few-group constants with burnup dependence to be used in the already developed reactor core models. These core calculations are performed using CITVAP 3-D diffusion code, which is well-known reactor code based on CITATION. Subsequently the results are compared with those obtained by the deterministic calculation line used by INVAP, which uses the Collision Probability Condor cell-code to obtain few-group constants. Finally the results are compared with the experimental data obtained from the reactor information for several operation cycles. As a result several evaluations are performed, including a code to code cell comparison at cell and core level and calculation-experiment comparison at core level in order to evaluate the Serpent code actual capabilities. (author)

  1. Comparison of SERPENT and CASMO-5M for pressurized water reactors models

    International Nuclear Information System (INIS)

    Hursin, M.; Vasiliev, A.; Ferroukhi, H.; Pautz, A.

    2013-01-01

    The objective of this work is to perform a preliminary assessment of the capability of SERPENT to generate cross sections for a PWR Beginning-of-Life (BOL) isothermal mini-core by comparing a SERPENT/PARCS solution with the results obtained using a CASMO-5M/PARCS approach. The PARCS code is used instead of the usual SIMULATE-3 to analyze the Swiss Reactors, because interfaces with PARCS already exist to obtain neutronic data from SERPENT. For the PWR configurations, the differences between CASMO-5M and SERPENT solutions are within 200 pcm at the assembly level and thus rather small when considering the deterministic transport method (energy/angular/space discretization) in CASMO-5M versus the stochastic treatment of SERPENT, the statistical uncertainties in the Monte-Carlo approach as well as the eventual differences in nuclear data used by both codes. At the 2D mini-core level, no major difference is observed when comparing PARCS run with CASMO-5M versus SERPENT cross sections. For the generation of kinetic parameters, non trivial differences are observed due both to the methods and the data used. For the relatively limited number of configurations considered, it is hard to make any definitive statement on the benefits of using Monte Carlo codes in terms of nuclear data generation. (authors)

  2. Them that believe: a postmodern exploration of the contemporary Christian serpent-handlers of Appalachia

    Directory of Open Access Journals (Sweden)

    Ralph W. Hood

    2009-01-01

    Full Text Available The call for a new paradigm is loud and clear and consistent with postmodern methods. They are no gold standard to be applied to all investigations; no master narrative to be defended. Interdisciplinary, as the author tries to demonstrate, can mean not only cooperation among disciplines, but also the use of a variety of often discipline favoured methods by a single investigator or a team of investigators whose location within a particular ‘discipline’ is both historically contingent and likely dated in terms of its usefulness. Likewise, the use of multilevel considerations means that the diversity of methods and approaches at various levels of abstraction are necessary to begin any study of religious phenomena in their immense complexity. This study of serpent handlers focuses upon archival research; hermeneutical explorations of textual criticism of the Bible; ethnography linked to videotapes; phenomenological interviews analyzed in terms of a hermeneutical method that reveals the meaningfulness of handling serpents, being anointed, and the experience of near death from serpent bites. The author is committed to exploring the meaning of serpent handling from personal and cultural perspectives, and also takes into account psychological theories to link the symbolic and sign value of serpents that further does justice to the power of the serpent to elicit genuine religious experiences and to serve as an apologetic for a tradition that has been maligned and misunderstood by lay persons and scholars alike.

  3. Verification of Serpent code for the fuel analysis of a PBMR; Verificacion del codigo SERPENT para el analisis de combustible para un PBMR

    Energy Technology Data Exchange (ETDEWEB)

    Bastida O, G. E.; Francois L, J. L., E-mail: gbo729@yahoo.com.mx [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico)

    2015-09-15

    In this paper the models and simulations with the Monte Carlo code Serpent are presented, as well as the obtained results of the different analyzed cases in order to verify the suitability or reliability of the use of this code to ensure favorable results in the realization of a neutronic analysis of fuel for a Pebble Bed Modular Reactor (PBMR). Comparisons were made with the results reported in a report by the OECD/Nea relative to a high temperature reactor of spheres bed with plutonium reactor grade as fuel. The results show that the use of Serpent is appropriate, as these results are comparable with those reported in the report. (Author)

  4. Comparison of Serpent and HELIOS-2 as applied for the PWR few-group cross section generation

    International Nuclear Information System (INIS)

    Fridman, E.; Leppaenen, J.; Wemple, C.

    2013-01-01

    This paper discusses recent modifications to the Serpent Monte Carlo code methodology and related to the calculation of few-group diffusion coefficients and reflector discontinuity factors The new methods were assessed in the following manner. First, few-group homogenized cross sections calculated by Serpent for a reference PWR core were compared with those generated 1 commercial deterministic lattice transport code HELIOS-2. Second, Serpent and HELIOS-2 fe group cross section sets were later employed by nodal diffusion code DYN3D for the modeling the reference PWR core. Finally, the nodal diffusion results obtained using the both cross section sets were compared with the full core Serpent Monte Carlo solution. The test calculations show that Serpent can calculate the parameters required for nodal analyses similar to conventional deterministic lattice codes. (authors)

  5. Validation of the Serpent 2-DYNSUB code sequence using the Special Power Excursion Reactor Test III (SPERT III)

    International Nuclear Information System (INIS)

    Knebel, Miriam; Mercatali, Luigi; Sanchez, Victor; Stieglitz, Robert; Macian-Juan, Rafael

    2016-01-01

    Highlights: • Full few-group cross section tables created by Monte Carlo lattice code Serpent 2. • Serpent 2 group constant methodology verified for HFP static and transient cases. • Serpent 2-DYNSUB tool chainvalidated using SPERT III REA experiments. • Serpent 2-DYNSUB tool chain suitable to model RIAs in PWRs. - Abstract: The Special Power Excursion Reactor Test III (SPERT III) is studied using the Serpent 2-DYNSUB code sequence in order to validate it for modeling reactivity insertion accidents (RIA) in PWRs. The SPERT III E-core was a thermal research reactor constructed to analyze reactor dynamics. Its configuration resembles a commercial PWR on terms of fuel type, choice of moderator, coolant flow and system pressure. The initial conditions of the rod ejection accident experiments (REA) performed cover cold startup, hot startup, hot standby and operating power scenarios. Eight of these experiments were analyzed in detail. Firstly, multi-dimensional nodal diffusion cross section tables were created for the three-dimensional reactor simulator DYNSUB employing the Monte Carlo neutron transport code Serpent 2. In a second step, DYNSUB stationary simulations were compared to Monte Carlo reference three-dimensional full scale solutions obtained with Serpent 2 (cold startup conditions) and Serpent 2/SUBCHANFLOW (operating power conditions) with a good agreement being observed. The latter tool is an internal coupling of Serpent 2 and the sub-channel thermal-hydraulics code SUBCHANFLOW. Finally, DYNSUB was utilized to study the eight selected transient experiments. Results were found to match measurements well. As the selected experiments cover much of the possible transient (delayed super-critical, prompt super-critical and super-prompt critical excursion) and initial conditions (cold and hot as well as zero, little and full power reactor states) one expects in commercial PWRs, the obtained results give confidence that the Serpent 2-DYNSUB tool chain is

  6. Generation of cross-sections and reference solutions using the code Serpent

    International Nuclear Information System (INIS)

    Gomez T, A. M.; Delfin L, A.; Del Valle G, E.

    2012-10-01

    Serpent is a code that solves the neutron transport equations using the Monte Carlo method that besides generating reference solutions in stationary state for complex geometry problems, has been specially designed for physical applications of cells, what includes the generation of homogenized cross-sections for several energy groups. In this work a calculation methodology is described using the code Serpent to generate the necessary cross-sections to carry out calculations with the code TNXY, developed in 1993 in the Nuclear Engineering Department of the Instituto Politecnico Nacional (Mexico) by means of an interface programmed in Octave. The computation program TNXY solves the neutron transport equations for several energy groups in stationary state and geometry X Y using the Discreet Ordinates method (S N ). To verify and to validate the methodology the results of TNXY were compared with those calculated by Serpent giving minor differences to 0.55% in the value of the multiplication factor. (Author)

  7. Verification of Serpent code for the fuel analysis of a PBMR

    International Nuclear Information System (INIS)

    Bastida O, G. E.; Francois L, J. L.

    2015-09-01

    In this paper the models and simulations with the Monte Carlo code Serpent are presented, as well as the obtained results of the different analyzed cases in order to verify the suitability or reliability of the use of this code to ensure favorable results in the realization of a neutronic analysis of fuel for a Pebble Bed Modular Reactor (PBMR). Comparisons were made with the results reported in a report by the OECD/Nea relative to a high temperature reactor of spheres bed with plutonium reactor grade as fuel. The results show that the use of Serpent is appropriate, as these results are comparable with those reported in the report. (Author)

  8. Comparison of KANEXT and SERPENT for fuel depletion calculations of a sodium fast reactor

    International Nuclear Information System (INIS)

    Lopez-Solis, R.C.; Francois, J.L.; Becker, M.; Sanchez-Espinoza, V.H.

    2014-01-01

    As most of Generation-IV systems are in development, efficient and reliable computational tools are needed to obtain accurate results in reasonably computer time. In this study, KANEXT code system is presented and validated against the well-known Monte Carlo SERPENT code, for fuel depletion calculations of a sodium fast reactor (SFR). The KArlsruhe Neutronic EXtended Tool (KANEXT) is a modular code system for deterministic reactor calculations, consisting of one kernel and several modules. Results obtained with KANEXT for the SFR core are in good agreement with the ones of SERPENT, e.g. the neutron multiplication factor and the isotopes evolution with burn-up. (author)

  9. Full Core modeling techniques for research reactors with irregular geometries using Serpent and PARCS applied to the CROCUS reactor

    International Nuclear Information System (INIS)

    Siefman, Daniel J.; Girardin, Gaëtan; Rais, Adolfo; Pautz, Andreas; Hursin, Mathieu

    2015-01-01

    Highlights: • Modeling of research reactors. • Serpent and PARCS coupling. • Lattice physics codes modeling techniques. - Abstract: This paper summarizes the results of modeling methodologies developed for the zero-power (100 W) teaching and research reactor CROCUS located in the Laboratory for Reactor Physics and Systems Behavior (LRS) at the Swiss Federal Institute of Technology in Lausanne (EPFL). The study gives evidence that the Monte Carlo code Serpent can be used effectively as a lattice physics tool for small reactors. CROCUS’ core has an irregular geometry with two fuel zones of different lattice pitches. This and the reactor’s small size necessitate the use of nonstandard cross-section homogenization techniques when modeling the full core with a 3D nodal diffusion code (e.g. PARCS). The primary goal of this work is the development of these techniques for steady-state neutronics and future transient neutronics analyses of not only CROCUS, but research reactors in general. In addition, the modeling methods can provide useful insight for analyzing small modular reactor concepts based on light water technology. Static computational models of CROCUS with the codes Serpent and MCNP5 are presented and methodologies are analyzed for using Serpent and SerpentXS to prepare macroscopic homogenized group cross-sections for a pin-by-pin model of CROCUS with PARCS. The most accurate homogenization scheme lead to a difference in terms of k eff of 385 pcm between the Serpent and PARCS model, while the MCNP5 and Serpent models differed in terms of k eff by 13 pcm (within the statistical error of each simulation). Comparisons of the axial power profiles between the Serpent model as a reference and a set of PARCS models using different homogenization techniques showed a consistent root-mean-square deviation of ∼8%, indicating that the differences are not due to the homogenization technique but rather arise from the definition of the diffusion coefficients

  10. Fuel burn analysis of a sodium fast reactor with KANEXT and Serpent; Analisis de quemado de combustible de un reactor rapido de sodio con KANEXT y SERPENT

    Energy Technology Data Exchange (ETDEWEB)

    Lopez S, R. C.; Francois L, J. L., E-mail: rcarlos.lope@gmail.com [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Paseo Cuauhnahuac 8532, 62550 Jiutepec, Morelos (Mexico)

    2015-09-15

    The fast reactors cooled by sodium are one of the options considered in the Generation IV. Since most of the reactors of Fourth Generation are still in development stage, is necessary to have efficient and reliable computational tools, this in order to obtain accurate results in reasonable computational times. In this paper is introduced and describes the deterministic code KANEXT (KArlsruhe Neutronic EXtended Tool) and is compared against a Monte Carlo code of more diffusion: Serpent. KANEXT, being a modular code requires the interaction of different modules to perform a job, this interaction of modules is described in this article. The parameters to be compared are the results of the neutron multiplication effective factor and the evolution of isotopes during the burning. The mentioned comparison is carried out for a fast reactor cooled by sodium of relatively small size compared to commercial size reactors. In this paper the particularities of the reactor are described, important for the analysis such as geometry, enrichments, reflector, etc. The considerations in the implementation in both codes are also described, as are simplifications, length of the burning steps, possible solutions of the Bateman equations for the burning fuel in Serpent and the solution options for transport (P3) and diffusion (P1) in KANEXT. The results show good correspondence between Serpent and KANEXT, which give confidence to continue using KANEXT as the main tool. Respect to computation time, time saving is evident with the use of deterministic codes instead of Monte Carlo codes, in this particular case, the time savings using KANEXT is about 98.5% of the time used by Serpent. (Author)

  11. The Serpent Column : The persistent meanings of a pagan relic in Christian and Islamic Constantinople

    NARCIS (Netherlands)

    Strootman, Rolf

    2014-01-01

    In the heart of Istanbul, on the site of the former Hippodrome, stand the remains of the Serpent Column, one of the most ancient and most enigmatic monuments in the city: a three-headed snake made of bronze to which various sacral and magical properties have been attributed in the past by pagans,

  12. SERPent: Automated reduction and RFI-mitigation software for e-MERLIN

    Science.gov (United States)

    Peck, Luke W.; Fenech, Danielle M.

    2013-08-01

    The Scripted E-merlin Rfi-mitigation PipelinE for iNTerferometry (SERPent) is an automated reduction and RFI-mitigation procedure utilising the SumThreshold methodology (Offringa et al., 2010a), originally developed for the LOFAR pipeline. SERPent is written in the Parseltongue language enabling interaction with the Astronomical Image Processing Software (AIPS) program. Moreover, SERPent is a simple 'out of the box' Python script, which is easy to set up and is free of compilers. In addition to the flagging of RFI affected visibilities, the script also flags antenna zero-amplitude dropouts and Lovell telescope phase calibrator stationary scans inherent to the e-MERLIN system. Both the flagging and computational performances of SERPent are presented here, for e-MERLIN commissioning datasets for both L-band (1.3-1.8 GHz) and C-band (4-8 GHz) observations. RFI typically amounts to future interferometers such as the SKA and the associated pathfinders (MeerKAT and ASKAP), where the vast data sizes (>TB) make traditional astronomer interactions unfeasible.

  13. Dwellers of the Sky: Serpent in the Greco-Roman Zodiac

    Directory of Open Access Journals (Sweden)

    dr.Wael Sayed Soliman

    2015-01-01

    Full Text Available The Ancient Egyptians were close observers of the heavenly bodies behavior from prehistoric times, which evidenced by the numerous astronomical tools and scenes they left. Throughout the Egyptian history, images of night sky decorated coffins, tombs, temples and some other different kinds of monuments. These images served as a theoretical and visual tribute to the solar cycle and bore strong renewing associations. This article investigates the function of the serpent within a various collection of ancient Egyptian zodiacs dating back to the Greco-Roman Period, which was readily incorporated into the existing tradition of astronomical iconography. In order to explain the adoption of the serpent, this article examines its role in the astronomical images. There are no actual evidences for serpent iconography found in ancient astronomical scenes before the Greco-Roman Period, I ample to prove that knowledge of those creatures existed from the earliest time, and pervade the Egyptian symbolism. The details of the serpent picture have sketched and valid for the Greco-Roman Egypt, starting from the Third Century B.C.

  14. Numerical verification/validation of the theory of coupled reactors for deuterium critical assembly, using MCNP5 and Serpent codes

    International Nuclear Information System (INIS)

    Hussein, M.S; Lewis, B.J.; Bonin, H.W.

    2013-01-01

    The theory of multipoint coupled reactors developed by multi-group transport is verified by using the probabilistic transport code MCNP5 and the continuous-energy Monte Carlo reactor physics burnup calculation Serpent code. The verification was performed by calculating the multiplication factors (or criticality factors) and coupling coefficients for a two-region test reactor known as the Deuterium Critical Assembly, DCA. The multiplication factors k eff calculated numerically and independently from simulations of the DCA by MCNP5 and Serpent codes are compared with the multiplication factors k eff calculated based on the coupled reactor theory. Excellent agreement was obtained between the multiplication factors k eff calculated with the Serpent code, with MCNP5, and from the coupled reactor theory. This analysis demonstrates that the Serpent code is valid for the multipoint coupled reactor calculations. (author)

  15. Numerical verification/validation of the theory of coupled reactors for deuterium critical assembly, using MCNP5 and Serpent codes

    Energy Technology Data Exchange (ETDEWEB)

    Hussein, M.S, E-mail: mohamed.hussein@rmc.ca [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, Ontario (Canada); Lewis, B.J., E-mail: Brent.Lewis@uoit.ca [Univ. of Ontario Inst. of Technology, Faculty of Energy Systems and Nuclear Science, Oshawa, Ontario (Canada); Bonin, H.W., E-mail: bonin-h@rmc.ca [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, Ontario (Canada)

    2013-07-01

    The theory of multipoint coupled reactors developed by multi-group transport is verified by using the probabilistic transport code MCNP5 and the continuous-energy Monte Carlo reactor physics burnup calculation Serpent code. The verification was performed by calculating the multiplication factors (or criticality factors) and coupling coefficients for a two-region test reactor known as the Deuterium Critical Assembly, DCA. The multiplication factors k{sub eff} calculated numerically and independently from simulations of the DCA by MCNP5 and Serpent codes are compared with the multiplication factors k{sub eff} calculated based on the coupled reactor theory. Excellent agreement was obtained between the multiplication factors k{sub eff} calculated with the Serpent code, with MCNP5, and from the coupled reactor theory. This analysis demonstrates that the Serpent code is valid for the multipoint coupled reactor calculations. (author)

  16. Modeling of FREYA fast critical experiments with the Serpent Monte Carlo code

    International Nuclear Information System (INIS)

    Fridman, E.; Kochetkov, A.; Krása, A.

    2017-01-01

    Highlights: • FREYA – the EURATOM project executed to support fast lead-based reactor systems. • Critical experiments in the VENUS-F facility during the FREYA project. • Characterization of the critical VENUS-F cores with Serpent. • Comparison of the numerical Serpent results to the experimental data. - Abstract: The FP7 EURATOM project FREYA has been executed between 2011 and 2016 with the aim of supporting the design of fast lead-cooled reactor systems such as MYRRHA and ALFRED. During the project, a number of critical experiments were conducted in the VENUS-F facility located at SCK·CEN, Mol, Belgium. The Monte Carlo code Serpent was one of the codes applied for the characterization of the critical VENUS-F cores. Four critical configurations were modeled with Serpent, namely the reference critical core, the clean MYRRHA mock-up, the full MYRRHA mock-up, and the critical core with the ALFRED island. This paper briefly presents the VENUS-F facility, provides a detailed description of the aforementioned critical VENUS-F cores, and compares the numerical results calculated by Serpent to the available experimental data. The compared parameters include keff, point kinetics parameters, fission rate ratios of important actinides to that of U235 (spectral indices), axial and radial distribution of fission rates, and lead void reactivity effect. The reported results show generally good agreement between the calculated and experimental values. Nevertheless, the paper also reveals some noteworthy issues requiring further attention. This includes the systematic overprediction of reactivity and systematic underestimation of the U238 to U235 fission rate ratio.

  17. 3D simulation of a core operation cycle of a BWR using Serpent; Simulacion 3D de un ciclo de operacion del nucleo de un BWR usando SERPENT

    Energy Technology Data Exchange (ETDEWEB)

    Barrera Ch, M. A.; Del Valle G, E. [IPN, Escuela Superior de Fisica y Matematicas, Av. IPN s/n, Col. Lindavista, 07738 Ciudad de Mexico (Mexico); Gomez T, A. M., E-mail: rionchez@icloud.com [ININ, Departamento de Sistemas Nucleares, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2016-09-15

    This work had the main goal to develop a methodology to obtain the length of an operating cycle of the core of a BWR under different operating states using the Serpent code. The reactor core modeled in Serpent is composed of 444 fuel assemblies (120 with fresh fuels and 324 fuels from previous cycles), 109 cruciform control rods and light water as moderator and coolant. Once the core of the reactor was modeled in Serpent (Three-dimensional) without considering the cruciform control rods, a simulation was carried out with different steps of burning in the operational state with the average values of the fuel temperature (900 K), moderator temperature (600 K) and voids fraction equal to 0.4. In addition, the thermal power considered was 2017 MWt. This operational state was chosen because a previous analysis (not shown in this work) was carried out in 4 types of control cells. The first and second control cell has all of its natural uranium fuel pellets, with control rod and without control rod respectively. The third and fourth control cell types have various types of enrichment, both natural uranium and gadolinium in their fuel pellets, with control rod and without control rod. The conclusion of this previous analysis was that the behavior of the effective multiplication factor along the fuel burnout within the four control cell types was almost unaffected by the fuel temperature but was affected by the voids fraction. Thus, for this operating cycle in the operating state defined above, its length was 14,63052 GW t/Tm. In addition, at the end of this cycle, the decay heat obtained was equal to 116.71 MWt and the inventory of the most important isotopes to be considered was obtained, such as some isotopes of uranium, neptune, plutonium, americium and curio. (Author)

  18. Serpent-COREDAX analysis of CANDU-6 time-average model

    Energy Technology Data Exchange (ETDEWEB)

    Motalab, M.A.; Cho, B.; Kim, W.; Cho, N.Z.; Kim, Y., E-mail: yongheekim@kaist.ac.kr [Korea Advanced Inst. of Science and Technology (KAIST), Dept. of Nuclear and Quantum Engineering Daejeon (Korea, Republic of)

    2015-07-01

    COREDAX-2 is the nuclear core analysis nodal code that has adopted the Analytic Function Expansion Nodal (AFEN) methodology which has been developed in Korea. AFEN method outperforms in terms of accuracy compared to other conventional nodal methods. To evaluate the possibility of CANDU-type core analysis using the COREDAX-2, the time-average analysis code system was developed. The two-group homogenized cross-sections were calculated using Monte Carlo code, Serpent2. A stand-alone time-average module was developed to determine the time-average burnup distribution in the core for a given fuel management strategy. The coupled Serpent-COREDAX-2 calculation converges to an equilibrium time-average model for the CANDU-6 core. (author)

  19. DRAGON and SERPENT 2-D modelling of the SLOWPOKE-2 reactor at Ecole Polytechnique Montreal

    International Nuclear Information System (INIS)

    Raouafi, H.; Marleau, G.

    2012-01-01

    DRAGON is a deterministic code that can be used to perform lattice cell calculations based on numerical solutions of neutron transport equation. DRAGON can also be used for full core 2-D and 3-D simulations in transport. One alternative to the use of such a deterministic code consist in following the history of neutrons in the core based on statistical Monte Carlo simulation with codes like MCNP and SERPENT. This second calculation approach has been used successfully for SLOWPOKE-2 simulation in the past. Here we present a comparison between DRAGON and SERPENT calculations for the SLOWPOKE-2 reactor. We also compare the flux distribution obtained using both codes for a copper sample placed inside a small irradiation site. (author)

  20. Fuel burn analysis of a sodium fast reactor with KANEXT and Serpent

    International Nuclear Information System (INIS)

    Lopez S, R. C.; Francois L, J. L.

    2015-09-01

    The fast reactors cooled by sodium are one of the options considered in the Generation IV. Since most of the reactors of Fourth Generation are still in development stage, is necessary to have efficient and reliable computational tools, this in order to obtain accurate results in reasonable computational times. In this paper is introduced and describes the deterministic code KANEXT (KArlsruhe Neutronic EXtended Tool) and is compared against a Monte Carlo code of more diffusion: Serpent. KANEXT, being a modular code requires the interaction of different modules to perform a job, this interaction of modules is described in this article. The parameters to be compared are the results of the neutron multiplication effective factor and the evolution of isotopes during the burning. The mentioned comparison is carried out for a fast reactor cooled by sodium of relatively small size compared to commercial size reactors. In this paper the particularities of the reactor are described, important for the analysis such as geometry, enrichments, reflector, etc. The considerations in the implementation in both codes are also described, as are simplifications, length of the burning steps, possible solutions of the Bateman equations for the burning fuel in Serpent and the solution options for transport (P3) and diffusion (P1) in KANEXT. The results show good correspondence between Serpent and KANEXT, which give confidence to continue using KANEXT as the main tool. Respect to computation time, time saving is evident with the use of deterministic codes instead of Monte Carlo codes, in this particular case, the time savings using KANEXT is about 98.5% of the time used by Serpent. (Author)

  1. Burnup calculation of a CANDU6 reactor using the Serpent and MCNP6 codes

    Energy Technology Data Exchange (ETDEWEB)

    Hussein, M.S.; Bonin, H.W., E-mail: mohamed.hussein@rmc.ca, E-mail: bonin-h@rmc.ca [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, ON (Canada); Lewis, B.J., E-mail: Brent.Lewis@uoit.ca [Univ. of Ontario Inst. of Tech., Faculty of Energy Systems and Nuclear Science, Oshawa, ON (Canada)

    2014-07-01

    A study of fuel burnup for the CANDU6 reactor is carried out to validate the most recent versions of the probabilistic transport code (MCNP6) and the continuous energy burnup calculation code (Serpent). These two codes allow for 3-D geometry calculation accounting for a detailed analysis without unit-cell homogenization. On the other hand, the WIMS-AECL computer program is used to model neutron transport in nuclear-reactor lattices for design, safety analysis, and operation. It works with two-dimensional regions and can perform collision probability calculations for a periodic structure of the lattice cell. In the present work, the multiplication factor, the total flux and fuel burnup could be calculated for a CANDU6 nuclear reactor based on the GENTILLY-2 core design. The MCNP6 and Serpent codes provide a calculation of the track length estimated flux per neutron source. This estimated flux is then scaled with normalization to the reactor power in order to provide a flux in unit of n/cm{sup 2}s. Good agreement is observed between the actual total flux calculated by MCNP6, Serpent and WIMS-AECL. The effective multiplication factors of the whole core CANDU6 reactor are further calculated as a function of burnup and further compared to those calculated by WIMS-AECL where excellent agreement is also obtained. (author)

  2. Burnup calculation of a CANDU6 reactor using the Serpent and MCNP6 codes

    International Nuclear Information System (INIS)

    Hussein, M.S.; Bonin, H.W.; Lewis, B.J.

    2014-01-01

    A study of fuel burnup for the CANDU6 reactor is carried out to validate the most recent versions of the probabilistic transport code (MCNP6) and the continuous energy burnup calculation code (Serpent). These two codes allow for 3-D geometry calculation accounting for a detailed analysis without unit-cell homogenization. On the other hand, the WIMS-AECL computer program is used to model neutron transport in nuclear-reactor lattices for design, safety analysis, and operation. It works with two-dimensional regions and can perform collision probability calculations for a periodic structure of the lattice cell. In the present work, the multiplication factor, the total flux and fuel burnup could be calculated for a CANDU6 nuclear reactor based on the GENTILLY-2 core design. The MCNP6 and Serpent codes provide a calculation of the track length estimated flux per neutron source. This estimated flux is then scaled with normalization to the reactor power in order to provide a flux in unit of n/cm 2 s. Good agreement is observed between the actual total flux calculated by MCNP6, Serpent and WIMS-AECL. The effective multiplication factors of the whole core CANDU6 reactor are further calculated as a function of burnup and further compared to those calculated by WIMS-AECL where excellent agreement is also obtained. (author)

  3. 3D simulation of a core operation cycle of a BWR using Serpent

    International Nuclear Information System (INIS)

    Barrera Ch, M. A.; Del Valle G, E.; Gomez T, A. M.

    2016-09-01

    This work had the main goal to develop a methodology to obtain the length of an operating cycle of the core of a BWR under different operating states using the Serpent code. The reactor core modeled in Serpent is composed of 444 fuel assemblies (120 with fresh fuels and 324 fuels from previous cycles), 109 cruciform control rods and light water as moderator and coolant. Once the core of the reactor was modeled in Serpent (Three-dimensional) without considering the cruciform control rods, a simulation was carried out with different steps of burning in the operational state with the average values of the fuel temperature (900 K), moderator temperature (600 K) and voids fraction equal to 0.4. In addition, the thermal power considered was 2017 MWt. This operational state was chosen because a previous analysis (not shown in this work) was carried out in 4 types of control cells. The first and second control cell has all of its natural uranium fuel pellets, with control rod and without control rod respectively. The third and fourth control cell types have various types of enrichment, both natural uranium and gadolinium in their fuel pellets, with control rod and without control rod. The conclusion of this previous analysis was that the behavior of the effective multiplication factor along the fuel burnout within the four control cell types was almost unaffected by the fuel temperature but was affected by the voids fraction. Thus, for this operating cycle in the operating state defined above, its length was 14,63052 GW t/Tm. In addition, at the end of this cycle, the decay heat obtained was equal to 116.71 MWt and the inventory of the most important isotopes to be considered was obtained, such as some isotopes of uranium, neptune, plutonium, americium and curio. (Author)

  4. Filogenia e filogeografia do grupo Bothrops neuwiedi (Serpentes, Squamata)

    OpenAIRE

    Tais Machado

    2015-01-01

    O grupo Bothrops neuwiedi é composto por serpentes neotropicais que desempenham grande impacto na saúde pública, em decorrência de acidentes ofídicos. O grupo apresenta ampla distribuição ao longo da diagonal seca de formações abertas, desde o nordeste do Brasil até o noroeste da Argentina. A taxonomia atual, baseada principalmente em dados morfológicos qualitativos, não recupera as linhagens evolutivas apontadas pelas abordagens moleculares. O objetivo deste trabalho foi investigar o grupo B...

  5. Analysis of a small PWR core with the PARCS/Helios and PARCS/Serpent code systems

    International Nuclear Information System (INIS)

    Baiocco, G.; Petruzzi, A.; Bznuni, S.; Kozlowski, T.

    2017-01-01

    Highlights: • The consistency between Helios and Serpent few-group cross sections is shown. • The PARCS model is validated against a Monte Carlo 3D model. • The fission and capture rates are compared. • The influence of the spacer grids on the axial power distribution is shown. - Abstract: Lattice physics codes are primarily used to generate cross-section data for nodal codes. In this work the methodology of homogenized constant generation was applied to a small Pressurized Water Reactor (PWR) core, using the deterministic code Helios and the Monte Carlo code Serpent. Subsequently, a 3D analysis of the PWR core was performed with the nodal diffusion code PARCS using the two-group cross section data sets generated by Helios and Serpent. Moreover, a full 3D model of the PWR core was developed using Serpent in order to obtain a reference solution. Several parameters, such as k eff , axial and radial power, fission and capture rates were compared and found to be in good agreement.

  6. The influence of circadian rhythms on the metabolism of the snake Bothrops jararaca (Serpentes, Viperidae = A influência dos ritmos circadianos no metabolismo da serpente Bothrops jararaca (Serpentes, Viperidae

    Directory of Open Access Journals (Sweden)

    José Geraldo Pereira da Cruz

    2008-07-01

    Full Text Available The thermoregulatory activity has led to an extensive search for correlations between physiological variables, including metabolic functions, and the ideal level of body temperature. Snakes were also often seen basking, when their body temperatures were relatively independent of ambient temperature, indicating successful thermoregulation. Bothrops jararaca were exposed to two different ambient temperatures (20 and 30oC over a time course of three weeks and oxygen consumption and body temperature were measured. The snakes exhibited a freerunning rhythm of body temperature. Metabolic rate wasincreased at the same circadian phase as the increase in body temperature in the 30oC. The increase of body temperature and oxygen consumption of B. jararaca occurs in the scotophase of the photoperiod, consistent with that of nocturnal species. However, prior to a scotophase period the snakes under 20oC maintain body temperature and oxygen consumption at higher levels during the day. These results demonstrate for the first time that ectothermic animals may display physiologically generated circadian rhythms of bodytemperature similar to those recorded in endotherms. Circadian rhythms allow animals to anticipate environmental changes: physiological parameters such as body temperature andmobilization of energy reserves have to be adjusted before the expected environmental changes actually take place.A atividade termorreguladora conduziu a uma busca extensiva para o entendimento das correlações entre as variáveis fisiológicas, incluindo as funções metabólicas e a temperatura corporal. Frequentes observações mostram que algumas serpentes podem se aquecer, sendo este aumento de temperatura independente da temperatura ambiente, indicando a termorregulação bem sucedida. Bothrops jararaca foramexpostas a dois ambientes com diferentes temperaturas (20 e 30oC durante três semanas, sendo mensuradas a temperatura corporal e o consumo de oxigênio. O aumento

  7. Monte Carlo code Serpent calculation of the parameters of the stationary nuclear fission wave

    Directory of Open Access Journals (Sweden)

    V. M. Khotyayintsev

    2017-12-01

    Full Text Available n this work, propagation of the stationary nuclear fission wave was simulated for series of fixed power values using Monte Carlo code Serpent. The wave moved in the axial direction in 5 m long cylindrical core of fast reactor with pure 238U raw fuel. Stationary wave mode arises some period later after the wave ignition and lasts sufficiently long to determine kef with high enough accuracy. The velocity characteristic of the reactor was determined as the dependence of the wave velocity on the neutron multiplication factor. As we have recently shown within a one-group diffusion description, the velocity characteristic is two-valued due to the effect of concentration mechanisms, while thermal feedback affects it only quantitatively. The shape and parameters of the velocity characteristic critically affect feasibility of the reactor design since stationary wave solutions of the lower branch are unstable and do not correspond to any real waves in self-regulated reactor, like CANDLE. In this work calculations were performed without taking into account thermal feedback. They confirm that theoretical dependence correctly describes the shape of the velocity characteristic calculated using the results of the Serpent modeling.

  8. On the use of SERPENT Monte Carlo code to generate few group diffusion constants

    Energy Technology Data Exchange (ETDEWEB)

    Piovezan, Pamela, E-mail: pamela.piovezan@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), Sao Paulo, SP (Brazil); Carluccio, Thiago; Domingos, Douglas Borges; Rossi, Pedro Russo; Mura, Luiz Felipe, E-mail: fermium@cietec.org.b, E-mail: thiagoc@ipen.b [Fermium Tecnologia Nuclear, Sao Paulo, SP (Brazil); Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The accuracy of diffusion reactor codes strongly depends on the quality of the groups constants processing. For many years, the generation of such constants was based on 1-D infinity cell transport calculations. Some developments using collision probability or the method of characteristics allow, nowadays, 2-D assembly group constants calculations. However, these 1-D and 2-D codes how some limitations as , for example, on complex geometries and in the neighborhood of heavy absorbers. On the other hand, since Monte Carlos (MC) codes provide accurate neutro flux distributions, the possibility of using these solutions to provide group constants to full-core reactor diffusion simulators has been recently investigated, especially for the cases in which the geometry and reactor types are beyond the capability of the conventional deterministic lattice codes. The two greatest difficulties on the use of MC codes to group constant generation are the computational costs and the methodological incompatibility between analog MC particle transport simulation and deterministic transport methods based in several approximations. The SERPENT code is a 3-D continuous energy MC transport code with built-in burnup capability that was specially optimized to generate these group constants. In this work, we present the preliminary results of using the SERPENT MC code to generate 3-D two-group diffusion constants for a PWR like assembly. These constants were used in the CITATION diffusion code to investigate the effects of the MC group constants determination on the neutron multiplication factor diffusion estimate. (author)

  9. Serpent: an alternative for the nuclear fuel cells analysis of a BWR; SERPENT: una alternativa para el analisis de celdas de combustible nuclear de un BWR

    Energy Technology Data Exchange (ETDEWEB)

    Silva A, L.; Del Valle G, E. [IPN, Escuela Superior de Fisica y Matematicas, Av. Instituto Politecnico Nacional s/n, U.P. Adolfo Lopez Mateos, Edificio 9, Col. San Pedro Zacatenco, 07738 Mexico D. F. (Mexico); Gomez T, A. M., E-mail: lidi.s.albarran@gmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    In the last ten years the diverse research groups in nuclear engineering of the Universidad Nacional Autonoma de Mexico and Instituto Politecnico Nacional (UNAM, IPN), as of research (Instituto Nacional de Investigaciones Nucleares, ININ) as well as the personnel of the Nuclear Plant Management of the Comision Federal de Electricidad have been using the codes Helios and /or CASMO-4 in the generation of cross sections (X S) of nuclear fuel cells of the cores corresponding to the Units 1 and 2 of the nuclear power plant of Laguna Verde. Both codes belong to the Studsvik-Scandpower Company who receives the payment for the use and their respective maintenance. In recent years, the code Serpent appears among the nuclear community distributed by the OECD/Nea which does not has cost neither in its use neither in its maintenance. The code is based on the Monte Carlo method and makes use of the processing in parallel. In the Escuela Superior de Fisica y Matematicas of the IPN, the personnel has accumulated certain experience in the use of Serpent under the direction of personal of the ININ; of this experience have been obtained for diverse fuel burned, the infinite multiplication factor for three cells of nuclear fuel, without control bar and with control bar for a known thermodynamic state fixed by: a) the fuel temperature (T{sub f}), b) the moderator temperature (T{sub m}) and c) the vacuums fraction (α). Although was not realized any comparison with the X S that the codes Helios and CASMO-4 generate, the results obtained for the infinite multiplication factor show the prospective tendencies with regard to the fuel burned so much in the case in that is not present the control bar like when it is. The results are encouraging and motivate to the study group to continue with the X S generation of a core in order to build the respective library of nuclear data as a following step and this can be used for the codes PARCS, of USA NRC, DYN3D of HZDR, or others developed locally

  10. Comparison of serpent and triton generated FEW group constants for APR1400 nuclear reactor core

    International Nuclear Information System (INIS)

    Elsawi, Mohamed A.; Alnoamani, Zainab

    2015-01-01

    The accuracy of full-core reactor power calculations using diffusion codes is strongly dependent on the quality of the homogenized cross sections and other few-group constants generated by lattice codes. For many years, deterministic lattice codes have been used to generate these constants using different techniques: the discrete ordinates, collision probability or the method of characteristics, just to name a few. These codes, however, show some limitations, for example, on complex geometries or near heavy absorbers as in modern pressurized water reactor (PWR) designs like the Korean Advanced Power Reactor 1400 (APR1400) core. The use of continuous-energy Monte Carlo (MC) codes to produce nuclear constants can be seen as an attractive option when dealing with fuel or reactor types that lie beyond the capabilities of conventional deterministic lattice transport codes. In this paper, the few-group constants generated by two of the state-of-the-art reactor physics codes, SERPENT and SCALE/TRITON, will be critically studied and their reliability for being used in subsequent diffusion calculations will be evaluated. SERPENT is a 3D, continuous-energy, Monte Carlo reactor physics code which has a built-in burn-up calculation capability. It has been developed at the Technical Research Center of Finland (VTT) since 2004. SCALE/TRITON, on the other hand, is a control module developed within the framework of SCALE package that enables performing deterministic 2-D transport calculations on nuclear reactor core lattices. The approach followed in this paper is as follows. First, the few-group nuclear constants for the APR1400 reactor core were generated using SERPENT (version 2.1.22) and NEWT (in SCALE version 6.1.2) codes. For both codes, the critical spectrum, calculated using the B1 method, was used as a weighting function. Second, 2-D diffusion calculations were performed using the US NRC core simulator PARCS employing the two few-group constant sets generated in the first

  11. Osteopetrosis and osteonecrosis in snake Boa constrictor Osteopetrose e osteocondrose em serpente Boa constrictor

    Directory of Open Access Journals (Sweden)

    N.M. Ocarino

    2008-10-01

    Full Text Available Uma jibóia (Boa constrictor, de onze anos de cativeiro, apresentou à seis meses um histórico de aumento de volume ao longo da coluna vertebral e perda progressiva dos movimentos e de apetite. Exames radiológicos revelaram aumento da opacidade, áreas de excrescências ósseas e inúmeras fraturas ao longo da coluna. Devido o prognóstico desfavorável, a serpente foi eutanasiada. À necropsia, aumento de volume com estenose do canal vertebral e compressão da medula espinhal foram observados, juntamente com fraturas completas de corpos vertebrais. O diagnóstico de osteopetrose e osteonecrose foi firmado à histologia.

  12. Cases of human envenoming caused by Philodryas olfersii and Philodryas patagoniensis (serpentes: Colubridae

    Directory of Open Access Journals (Sweden)

    Maria Elisabeth de Araújo

    1997-12-01

    Full Text Available The present paper reports two cases of human envenoming by colubrid snakes of Philodryas, considered as not poisonous, showing evidence of the clinical aspects and the evolution of the symptoms of envenoming. The similarity of these cases with those caused by Bothrops suggests a more careful evaluation on the victims considering the medical treatment to be adopted.O presente trabalho é um relato de dois casos de acidentes com colubrídeos (Philodryas olfersii e P. patagoniensis considerados não peçonhentos, que destaca as manifestações clínicas e as suas evoluções. A semelhança de tais acidentes com aqueles causados por serpentes Bothrops indica a necessidade de uma melhor avaliação dos pacientes quanto à terapêutica a ser adotada.

  13. Geographic distribution and apparent decline of Crotalus durissus terrificus (Laurenti, 1768; Serpentes, Viperidae) in Uruguay

    OpenAIRE

    Prigioni, Carlos M.; Borteiro, Claudio; Kolenc, Francisco; Colina, Marcelo; González, Enrique M.

    2013-01-01

    The rattlesnake Crotalus durissus terrificus (Laurenti, 1768; Serpentes, Viperidae) is a rare species in Uruguay, where it reaches the southern boundaries of its distribution. The most recent distribution map available for this species in Uruguay is based on a few specimens that were collected during the 1950s and 1960s. Herein, we make a comprehensive account of rattlesnake records in this country obtained from herpetological literature and other bibliographic sources, specimens accessioned ...

  14. Calculation of the radial and axial flux and power distribution for a CANDU 6 reactor with both the MCNP6 and Serpent codes

    International Nuclear Information System (INIS)

    Hussein, M.S.; Bonin, H.W.; Lewis, B.J.

    2014-01-01

    The most recent versions of the Monte Carlo-based probabilistic transport code MCNP6 and the continuous energy reactor physics burnup calculation code Serpent allow for a 3-D geometry calculation accounting for the detailed geometry without unit-cell homogenization. These two codes are used to calculate the axial and radial flux and power distributions for a CANDU6 GENTILLY-2 nuclear reactor core with 37-element fuel bundles. The multiplication factor, actual flux distribution and power density distribution were calculated by using a tally combination for MCNP6 and detector analysis for Serpent. Excellent agreement was found in the calculated flux and power distribution. The Serpent code is most efficient in terms of the computational time. (author)

  15. Calculation of the radial and axial flux and power distribution for a CANDU 6 reactor with both the MCNP6 and Serpent codes

    Energy Technology Data Exchange (ETDEWEB)

    Hussein, M.S.; Bonin, H.W., E-mail: mohamed.hussein@rmc.ca, E-mail: bonin-h@rmc.ca [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, ON (Canada); Lewis, B.J., E-mail: Brent.Lewis@uoit.ca [Univ. of Ontario Inst. of Tech., Faculty of Energy Systems and Nuclear Science, Oshawa, ON (Canada)

    2014-07-01

    The most recent versions of the Monte Carlo-based probabilistic transport code MCNP6 and the continuous energy reactor physics burnup calculation code Serpent allow for a 3-D geometry calculation accounting for the detailed geometry without unit-cell homogenization. These two codes are used to calculate the axial and radial flux and power distributions for a CANDU6 GENTILLY-2 nuclear reactor core with 37-element fuel bundles. The multiplication factor, actual flux distribution and power density distribution were calculated by using a tally combination for MCNP6 and detector analysis for Serpent. Excellent agreement was found in the calculated flux and power distribution. The Serpent code is most efficient in terms of the computational time. (author)

  16. Serpent: an alternative for the nuclear fuel cells analysis of a BWR

    International Nuclear Information System (INIS)

    Silva A, L.; Del Valle G, E.; Gomez T, A. M.

    2013-10-01

    In the last ten years the diverse research groups in nuclear engineering of the Universidad Nacional Autonoma de Mexico and Instituto Politecnico Nacional (UNAM, IPN), as of research (Instituto Nacional de Investigaciones Nucleares, ININ) as well as the personnel of the Nuclear Plant Management of the Comision Federal de Electricidad have been using the codes Helios and /or CASMO-4 in the generation of cross sections (X S) of nuclear fuel cells of the cores corresponding to the Units 1 and 2 of the nuclear power plant of Laguna Verde. Both codes belong to the Studsvik-Scandpower Company who receives the payment for the use and their respective maintenance. In recent years, the code Serpent appears among the nuclear community distributed by the OECD/Nea which does not has cost neither in its use neither in its maintenance. The code is based on the Monte Carlo method and makes use of the processing in parallel. In the Escuela Superior de Fisica y Matematicas of the IPN, the personnel has accumulated certain experience in the use of Serpent under the direction of personal of the ININ; of this experience have been obtained for diverse fuel burned, the infinite multiplication factor for three cells of nuclear fuel, without control bar and with control bar for a known thermodynamic state fixed by: a) the fuel temperature (T f ), b) the moderator temperature (T m ) and c) the vacuums fraction (α). Although was not realized any comparison with the X S that the codes Helios and CASMO-4 generate, the results obtained for the infinite multiplication factor show the prospective tendencies with regard to the fuel burned so much in the case in that is not present the control bar like when it is. The results are encouraging and motivate to the study group to continue with the X S generation of a core in order to build the respective library of nuclear data as a following step and this can be used for the codes PARCS, of USA NRC, DYN3D of HZDR, or others developed locally in the

  17. Using of the Serpent code based on the Monte-Carlo method for calculation of the VVER-1000 fuel assembly characteristics

    Directory of Open Access Journals (Sweden)

    V. V. Galchenko

    2016-12-01

    Full Text Available The description of calculation scheme of fuel assembly for preparation of few-group characteristics is considered with help of Serpent code. This code uses the Monte-Carlo method and energy continuous microscopic data libraries. Serpent code is devoted for calculation of fuel assembly characteristics, burnup calculations and preparation of few-group homogenized macroscopic cross-sections. The results of verification simulations in comparison with other codes (WIMS, HELIOS, NESSEL etc., which are used for neutron-physical analysis of VVER type fuel, are presented.

  18. Occurrence of Cryptosporidium (Apicomplexa, Cryptosporidiidae in Crotalus durissus terrificus (Serpentes, Viperidae in Brazil

    Directory of Open Access Journals (Sweden)

    Karasawa Andréa Satie Matsubara

    2002-01-01

    Full Text Available The objective of the present study was to investigate the prevalence of Cryptosporidium (Apicomplexa, Cryptosporidiidae in the snake Crotalus durissus terrificus (Serpentes, Viperidae. Fifty animals were evaluated for the presence of oocysts of Cryptosporidium sp. at the time of arrival and 30 and 60 days later. Intestinal washings with saline solution (1% body weight, fecal samples, and organ scrapings were collected during the study. Oocysts were concentrated by an ether-phosphate-buffered saline sedimentation technique and then separated by a density gradient centrifugation technique. Smears were made with the sediment and submitted to modified acid-fast and auramine-rhodamine staining. Cryptosporidium-positive smears were used as controls for the experimental findings. The overall prevalence of Cryptosporidium sp. oocysts was 14%. Among the positive snakes, oocysts were detected only in the intestinal washing in two specimens, only in the feces in four specimens, and in both materials at least once in one specimen. The positive snakes were predominantly from Santa Maria da Serra city State of São Paulo (57.1%. We also observed that all of the examinations that presented positive results were obtained at least 27 days after the capture of the animals.

  19. Validation of main nuclear libraries used in thorium reactors using the Serpent code

    International Nuclear Information System (INIS)

    Faga, Lucas J.

    2017-01-01

    The purpose of this work is to validate the library of the Serpent standard database for systems containing U-233, U-235, Th-232, Pu-239 and Pu-240. The project will support the other projects of the newly created study group of Nuclear Engineering Center (CEN) of Instituto de Pesquisas Energéticas e Nucleares (IPEN), linked to the study of several types of reactors and their application in thorium cycles, a subject that gains more and more visibility, due to strong and potential promises of energy revolution. The results obtained at the end of the simulations were satisfactory, with the multiplication factors being effective close to 100 PCM of the values provided by the benchmarks, as expected for a validated library. The minimum distance between these values was 2 PCM and the maximum of 280 PCM. The final analysis demonstrates that the ENDF / B-VII library has validated nuclear data for the isotopes of interest and may be used in future thorium study group projects

  20. Il serpente come Messia. Rappresentazione alla rovescia del Paradiso nel teatro e nel cinema del XX secolo

    Directory of Open Access Journals (Sweden)

    Yehuda Moraly

    2011-06-01

    Full Text Available This paper analyses the way Paradise appears in different Theatre or Film productions of the XXth century: a biblical epos by the Israelian director Rina Yerushalmi, a film that became a classic, Children of Paradise (Carné, Prévert, 1943, the last show of the Living Theater, Paradise now (1968, and a film by Peter Weir, Truman Show (1998. In all of these productions, the Serpent, deeply negative in the biblical text appears like a positive figure, a kind of Messiah.

  1. Effect of ultra high temperature ceramics as fuel cladding materials on the nuclear reactor performance by SERPENT Monte Carlo code

    Energy Technology Data Exchange (ETDEWEB)

    Korkut, Turgay; Kara, Ayhan; Korkut, Hatun [Sinop Univ. (Turkey). Dept. of Nuclear Energy Engineering

    2016-12-15

    Ultra High Temperature Ceramics (UHTCs) have low density and high melting point. So they are useful materials in the nuclear industry especially reactor core design. Three UHTCs (silicon carbide, vanadium carbide, and zirconium carbide) were evaluated as the nuclear fuel cladding materials. The SERPENT Monte Carlo code was used to model CANDU, PWR, and VVER type reactor core and to calculate burnup parameters. Some changes were observed at the same burnup and neutronic parameters (keff, neutron flux, absorption rate, and fission rate, depletion of U-238, U-238, Xe-135, Sm-149) with the use of these UHTCs. Results were compared to conventional cladding material zircalloy.

  2. Results from the second Galaxy Serpent web-based table top exercise utilizing the concept of nuclear forensics libraries

    International Nuclear Information System (INIS)

    Borgardt, James; Canaday, Jodi; Chamberlain, David

    2017-01-01

    Galaxy Serpent is a unique, virtual, web-based international tabletop series of exercises designed to mature the concept of National Nuclear Forensics Libraries (NNFLs). Teams participating in the second version of the exercise were provided synthetic sealed radioactive source data used to compile a model NNFL which then served as a comparative instrument in hypothetical scenarios involving sources out of regulatory control, allowing teams to successfully down-select and determine whether investigated sources were consistent with holdings in their model library. The methodologies utilized and aggregate results of the exercise will be presented, along with challenges encountered and benefits realized. (author)

  3. Epidemiologia do acidente por serpentes peçonhentas: estudo de casos atendidos em 1988

    Directory of Open Access Journals (Sweden)

    Lindioneza Adriano Ribeiro

    1995-10-01

    Full Text Available Foram avaliados aspectos epidemiológicos de acidentes por serpentes peçonhentas no Estado de São Paulo, Brasil, com base em prontuários de 322 pacientes e em entrevistas feitas com 209 deles e/ou seus acompanhantes. Os acidentes ocorreram principalmente com pessoas de 10 a 20 anos de idade, do sexo masculino, nos meses de outubro a abril e no período diurno. As regiões anatômicas mais freqüentemente picadas foram os pés, as mãos e as pernas. Bothrops, Crotalus e Micrurus foram responsáveis por, respectivamente, 95,0%, 4,4% e 0,6% dos casos. Não ocorreram óbitos, mas 2,2% dos pacientes apresentaram seqüelas. Dentre os 209 entrevistados, a ocupação de lavrador foi a mais freqüentemente relacionada ao acidente que, em aproximadamente 60% das vezes, ocorreu durante o trabalho. O total de 160 pacientes (76,6% submeteram-se a alguma forma de tratamento antes de chegarem a um serviço de saúde: foram mais comuns o uso de torniquete (50,2%, a expressão local na tentativa de retirar parte do veneno (33,5%, a colocação das mais diversas substâncias sobre o local da picada (36,8% e a ingestão de outras (12,9%; pouco mais de um quarto dos pacientes submeteram-se a alguma forma de tratamento médico antes de chegar ao HVB sendo mais comum a antissepsia (8,2%, a administração do antiveneno (6,2%, de anti-histamínicos (5,7% e de analgésicos (5,3%.

  4. Prevalência de Cryptosporidium serpentis em serpentes de cativeiro Prevalence of Cryptosporidium serpentis in captive snakes

    Directory of Open Access Journals (Sweden)

    Paulo Custório Ruggiero

    2011-11-01

    Full Text Available Cryptosporidium é um protozoário encontrado em uma grande variedade de espécies animais como responsável por casos de gastrite e enterite, porém com epidemiologia pouco conhecida em animais silvestres. A presente investigação teve como objetivo avaliar a prevalência de Cryptosporidium serpentis em lavado gástrico de serpentes mantidas em cativeiro no serpentário do Instituto Butantan (São Paulo, Brasil. A coleta foi realizada uma semana após alimentação, evitando, assim, a regurgitação devido à manipulação. Foram realizados esfregaços do sedimento do lavado gástrico, obtido por centrifugação, corados pela técnica de coloração de Kinyoun. Parte do sedimento foi submetido à técnica de RFLP-PCR para identificação da espécie de Cryptosporidium. O serpentário é dividido em três seções, por espécie - a primeira com oito jibóias (Boa constrictor amarali, a segunda com dez jararacas (Bothropoides jararaca e a última com sete cascavéis (Caudisona durissa. A prevalência de C. serpentis encontrada neste estudo para as serpentes C. durissa, B. jararaca e Boa c. amarali, foi de 57,14% (04/07, 40% (04/10 e 37,5% (03/08, respectivamente, revelando importante ocorrência desse protozoário em serpentes de cativeiro. Apesar da alta prevalência encontrada, apenas as jiboias apresentaram sintomas como perda de peso e regurgitação, refletindo uma sensibilidade diferente da espécie para C. serpentis.Cryptosporidium is a protozoan found in a wide variety of animal species which is responsible for gastritis and enteritis, but its epidemiology is poorly known in wild animals. The present investigation aimed to evaluate the prevalence of Cryptosporidium serpentis in gastric aspirate of captive snakes from the public serpentarium of the Butantan Institute (São Paulo, Brazil. Sampling was performed preferably one week after feeding, thereby preventing regurgitation due to manipulation. Smears were done from the gastric

  5. Determination of the physical parameters of the nuclear subcritical assembly Chicago 9000 of the IPN using the Serpent code; Determinacion de los parametros fisicos del conjunto subcritico nuclear Chicago 9000 del IPN usando el codigo SERPENT

    Energy Technology Data Exchange (ETDEWEB)

    Arriaga R, L.; Del Valle G, E. [IPN, Escuela Superior de Fisica y Matematicas, Av. Instituto Politecnico Nacional s/n, U.P. Adolfo Lopez Mateos, Col. San Pedro Zacatenco, 07738 Mexico D. F. (Mexico); Gomez T, A. M., E-mail: guten_tag_04@hotmail.com [ININ, Departamento de Sistemas Nucleares, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    For the Serpent code was developed the three-dimensional model corresponding to the nuclear subcritical assembly (S A) Chicago 9000 of the Escuela Superior de Fisica y Matematicas del Instituto Politecnico Nacional (ESFM-IPN). The model includes: a) the core, formed by 312 aluminum pipes that contain 5 nuclear fuel rods (natural uranium in metallic form), b) the multi-perforated plates where they penetrate the inferior part of each pipe to be able to remain in vertical form, c) water, acting as moderator and reflector, and d) the recipient lodging to the core. The pipes arrangement is hexagonal although the transversal section of the recipient that lodges to the core is circular. The entrance file for the Serpent code was generated with the data provided by the manual of the S A use about the composition and density of the fuel rods and others obtained in direct form of the rods, as the interior and external diameter, mass and height. Of the obtained physical parameters, those more approached to that reported in the manual of the subcritical assembly are the effective multiplication factor and the reproduction factor η. The differences can be because the description of the fuel rods provided by the manual of the S A use do not correspond those that are physically in the S A core. This difference consists on the presence of a circular central channel of 1.245 diameter centimeters in each fuel rod. The fuel rods reported in the mentioned manual do not have that channel. Although the obtained results are encouraging, we want to continue improving the model to incorporate in this the detectors, defined this way by the Serpent code, which could determine the existent neutrons flux in diverse points of interest like the axial or radial aligned points and to compare these with those that are obtained in an experimental way when a generating neutrons source (Pu-Be) is introduced. Added to this effort the cross sections for each unitary cell will be determined, so that

  6. Determination of the physical parameters of the nuclear subcritical assembly Chicago 9000 of the IPN using the Serpent code

    International Nuclear Information System (INIS)

    Arriaga R, L.; Del Valle G, E.; Gomez T, A. M.

    2013-10-01

    For the Serpent code was developed the three-dimensional model corresponding to the nuclear subcritical assembly (S A) Chicago 9000 of the Escuela Superior de Fisica y Matematicas del Instituto Politecnico Nacional (ESFM-IPN). The model includes: a) the core, formed by 312 aluminum pipes that contain 5 nuclear fuel rods (natural uranium in metallic form), b) the multi-perforated plates where they penetrate the inferior part of each pipe to be able to remain in vertical form, c) water, acting as moderator and reflector, and d) the recipient lodging to the core. The pipes arrangement is hexagonal although the transversal section of the recipient that lodges to the core is circular. The entrance file for the Serpent code was generated with the data provided by the manual of the S A use about the composition and density of the fuel rods and others obtained in direct form of the rods, as the interior and external diameter, mass and height. Of the obtained physical parameters, those more approached to that reported in the manual of the subcritical assembly are the effective multiplication factor and the reproduction factor η. The differences can be because the description of the fuel rods provided by the manual of the S A use do not correspond those that are physically in the S A core. This difference consists on the presence of a circular central channel of 1.245 diameter centimeters in each fuel rod. The fuel rods reported in the mentioned manual do not have that channel. Although the obtained results are encouraging, we want to continue improving the model to incorporate in this the detectors, defined this way by the Serpent code, which could determine the existent neutrons flux in diverse points of interest like the axial or radial aligned points and to compare these with those that are obtained in an experimental way when a generating neutrons source (Pu-Be) is introduced. Added to this effort the cross sections for each unitary cell will be determined, so that

  7. Radionuclide uptake by beaver and ruffed grouse in the Serpent River basin

    International Nuclear Information System (INIS)

    Clulow, F.V.

    1988-12-01

    Radionuclide levels were measured in tissues, gut contents, and diet items of adult beaver and ruffed grouse from the Serpent River drainage basin (which contains the city of Elliot Lake) and control sites in Ontario, and in beaver and muskrat fetuses from females taken in the same basin. Levels of radium 226 in beaver bone, muscle and kidney were highest in animals from locations close to uranium tailings; liver levels did not vary by site. Grouse taken near Elliot Lake has higher bone levels of radium 226 than distant controls; levels in other tissues did not vary by site. Environmental radium 226 levels were within ranges previously reported at these or similar locations elsewhere; levels in beaver and grouse gut contents reflected levels in diet items. Fetal beaver tissues had higher radium 226 levels than maternal tissues; fetal liver tissue carried higher levels than other body tissues in general; fetal levels varied with maternal levels but also inversely with fetal size (and thus age). Although muskrat fetal liver had more radium 226 than other tissues, levels were lower than maternal bone levels. In two grouse and two beaver, selected for their higher tissue levels of radium 226, neither thorium 232 nor thorium 230 were detected in bone, muscle, or liver samples, however other radionuclides were measured: uranium 238 in beaver and grouse bone, muscle and liver; thorium 228 in beaver bone and grouse muscle; polonium 210 was found in bone, muscle, and liver of both beaver and grouse sampled (except in one grouse muscle sample); lead 210 was measurable only in beaver bone and in one grouse liver sample. Concentration ratios exceeded unity only between some vegetation items and beaver bone at the Elliot Lake site; between vegetation and other beaver tissues values were never more than 0.19. In grouse, the concentration ratios from trembling aspen leaves to bone was 1.04; from other diet items and to other tissues the values were less than unity. Estimated

  8. Comparative analysis of results between CASMO, MCNP and Serpent for a suite of Benchmark problems on BWR reactors; Analisis comparativo de resultados entre CASMO, MCNP y SERPENT para una suite de problemas Benchmark en reactores BWR

    Energy Technology Data Exchange (ETDEWEB)

    Xolocostli M, J. V.; Vargas E, S.; Gomez T, A. M. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Reyes F, M. del C.; Del Valle G, E., E-mail: vicente.xolocostli@inin.gob.mx [IPN, Escuela Superior de Fisica y Matematicas, UP - Adolfo Lopez Mateos, Edif. 9, 07738 Mexico D. F. (Mexico)

    2014-10-15

    In this paper a comparison is made in analyzing the suite of Benchmark problems for reactors type BWR between CASMO-4, MCNP6 and Serpent code. The Benchmark problem consists of two different geometries: a fuel cell of a pin and assembly type BWR. To facilitate the study of reactors physics in the fuel pin their nuclear characteristics are provided to detail, such as burnt dependence, the reactivity of selected nuclide, etc. With respect to the fuel assembly, the presented results are regarding to infinite multiplication factor for burning different steps and different vacuum conditions. Making the analysis of this set of Benchmark problems provides comprehensive test problems for the next fuels generation of BWR reactors with high extended burned. It is important to note that when making this comparison the purpose is to validate the methodologies used in modeling for different operating conditions, if the case is of other BWR assembly. The results will be within a range with some uncertainty, considering that does not depend on code that is used. Escuela Superior de Fisica y Matematicas of Instituto Politecnico Nacional (IPN (Mexico) has accumulated some experience in using Serpent, due to the potential of this code over other commercial codes such as CASMO and MCNP. The obtained results for the infinite multiplication factor are encouraging and motivate the studies to continue with the generation of the X S of a core to a next step a respective nuclear data library is constructed and this can be used by codes developed as part of the development project of the Mexican Analysis Platform of Nuclear Reactors AZTLAN. (Author)

  9. 226Ra concentrations in crayfish tissues, water, and sediments from the Serpent River Basin in Northeastern Ontario, Canada

    International Nuclear Information System (INIS)

    Alikhan, M.A.

    1996-01-01

    Lower Serpent River, as well as Elliot, McCarthy and McCabe lakes had highest 226 Ra contamination, Chrisman, Quirke and Whiskey lakes a moderate one, Flack and Semiwhite lakes and the 'distant' control, Lake Wanapitei, the lowest. 226 Ra activity in Cambarus robustus tissues was directly related to their background levels. Thus, concentration coefficient (tissue/sediment concentrations) for 226 Ra ranged from 0.53 to 0.74 in highly contaminated Elliot and McCarthy lakes, 0.28 to 0.59 in moderately contaminated Quirke and Whiskey lakes, and from 0.27 to 3.44 in least contaminated Semiwhite and Flack lakes. Among various organs analysed, exoskeleton showed the highest (43.04 - 90.69%) and the tail muscles the lowest (2.95 -17.14%) 226 Ra activity. 226 Ra concentrations in the alimentary canal were considered a part of the ambient environment as they had not been absorbed

  10. THE INVESTIGATION OF BURNUP CHARACTERISTICS USING THE SERPENT MONTE CARLO CODE FOR A SODIUM COOLED FAST REACTOR

    Directory of Open Access Journals (Sweden)

    MEHMET E. KORKMAZ

    2014-06-01

    Full Text Available In this research, we investigated the burnup characteristics and the conversion of fertile 232Th into fissile 233U in the core of a Sodium-Cooled Fast Reactor (SFR. The SFR fuel assemblies were designed for burning 232Th fuel (fuel pin 1 and 233U fuel (fuel pin 2 and include mixed minor actinide compositions. Monte Carlo simulations were performed using Serpent Code1.1.19 to compare with CRAM (Chebyshev Rational Approximation Method and TTA (Transmutation Trajectory Analysis method in the burnup calculation mode. The total heating power generated in the system was assumed to be 2000 MWth. During the reactor operation period of 600 days, the effective multiplication factor (keff was between 0.964 and 0.954 and peaking factor is 1.88867.

  11. Comparative analysis of results between CASMO, MCNP and Serpent for a suite of Benchmark problems on BWR reactors

    International Nuclear Information System (INIS)

    Xolocostli M, J. V.; Vargas E, S.; Gomez T, A. M.; Reyes F, M. del C.; Del Valle G, E.

    2014-10-01

    In this paper a comparison is made in analyzing the suite of Benchmark problems for reactors type BWR between CASMO-4, MCNP6 and Serpent code. The Benchmark problem consists of two different geometries: a fuel cell of a pin and assembly type BWR. To facilitate the study of reactors physics in the fuel pin their nuclear characteristics are provided to detail, such as burnt dependence, the reactivity of selected nuclide, etc. With respect to the fuel assembly, the presented results are regarding to infinite multiplication factor for burning different steps and different vacuum conditions. Making the analysis of this set of Benchmark problems provides comprehensive test problems for the next fuels generation of BWR reactors with high extended burned. It is important to note that when making this comparison the purpose is to validate the methodologies used in modeling for different operating conditions, if the case is of other BWR assembly. The results will be within a range with some uncertainty, considering that does not depend on code that is used. Escuela Superior de Fisica y Matematicas of Instituto Politecnico Nacional (IPN (Mexico) has accumulated some experience in using Serpent, due to the potential of this code over other commercial codes such as CASMO and MCNP. The obtained results for the infinite multiplication factor are encouraging and motivate the studies to continue with the generation of the X S of a core to a next step a respective nuclear data library is constructed and this can be used by codes developed as part of the development project of the Mexican Analysis Platform of Nuclear Reactors AZTLAN. (Author)

  12. Serpentes da área urbana de Cuiabá, Mato Grosso: aspectos ecológicos e acidentes ofídicos associados

    Directory of Open Access Journals (Sweden)

    Carvalho Marcos André de

    1998-01-01

    Full Text Available São apresentadas informações sobre as serpentes da área urbana do Município de Cuiabá, Mato Grosso, potencialmente causadoras de acidentes ofídicos. As informações estão baseadas em exemplares doados por populares ao Núcleo de Ofiologia Regional de Mato Grosso (Normat entre 1986 e 1993 e em registros efetuados pelo Centro de Informações Anti-Veneno (Ciave entre 1988 e 1993, que não fazem referência ao animal causador. Foram catalogadas 37 espécies de serpentes, em 25 gêneros e 3 famílias, com hábitos predominantemente diurnos, terrestres e com dietas baseadas em anfíbios e/ou lagartos. Dentre os 307 acidentes ofídicos registrados, 56% foram causados por serpentes sem interesse médico e 44% constituíram acidentes de importância médica. Cerca de 99% dos acidentes de importância médica foram atribuídos ao gênero Bothrops (Bothrops moojeni e Bothrops neuwiedi seriam as principais causadoras. Dentre as espécies sem interesse médico, Philodryas olfersii e Waglerophis merremii provavelmente foram as principais responsáveis pela maior parte dos acidentes.

  13. Prevalence of Hepatozoon spp. (Apicomplexa, Hepatozoidae among recently captured Brazilian snakes Prevalência de Hepatozoon spp. (Apicomplexa, Hepatozoidae em serpentes recém-capturadas no Brasil

    Directory of Open Access Journals (Sweden)

    L.H. O'Dwyer

    2003-06-01

    Full Text Available The goal of this study was to determine the prevalence of Hepatozoon spp. infection in recently captured snakes from Botucatu, São Paulo State, Brazil. Blood was collected from all snakes by ventral tail venipuncture. Blood smears were air dried, fixed with methanol, and stained with 10% Giemsa solution. The slides were microscopically examined for detection of hemoparasites by light microscopy at 250x magnification. A total of 238 snakes from 23 species were examined, of which 135 (56.7% were venomous and 103 (43.3% non-venomous snakes. The more numerous venomous species sampled were Crotalus durissus terrificus (n=108 and Bothrops jararaca (n=17 and non-venomous snakes were Oxyrhopus guibei (n=35, Boa constrictor amarali (n=18, and Waglerophis merremi (n=13. Hepatozoon spp. infection was detected in 39 (16.4% snakes. The prevalence in venomous and non-venomous snakes was 20.0% and 11.7%, respectively. The highest prevalences observed were 38.9% for Boa constrictor amarali, 35.3% for Bothrops jararaca, and 19.4% for Crotalus durissus terrificus.O presente estudo teve como objetivo determinar a prevalência da infecção por Hepatozoon spp. em serpentes recém-capturadas da região de Botucatu, São Paulo. O sangue foi coletado de todas as serpentes por punção da veia caudal. Os esfregaços foram secos ao ar, fixados com metanol e corados com solução de Giemsa a 10%. Examinaram-se 238 serpentes pertencentes a 23 espécies, das quais 135 (56,7% eram venenosas e 103 (43,3% não venenosas. As espécies venenosas mais representativas foram Crotalus durissus terrificus (n=108 e Bothrops jararaca (n=17 e as não venenosas foram Oxyrhopus guibei (n=35, Boa constrictor amarali (n=18 e Waglerophis merremi (n=13. A infecção por Hepatozoon spp. foi detectada em 39 (16,4% serpentes. As prevalências em serpentes venenosas e não venenosas foram 20,0% e 11,7%, respectivamente. As maiores prevalências foram 38,9% para Boa constrictor amarali, 35

  14. Estudo comparativo do veneno botrópico de referência em relação ao veneno das serpentes Bothrops jararaca nascidas em cativeiro no Laboratório de Herpetologia do Instituto Butantan.

    OpenAIRE

    Iasmim Baptista de Farias

    2016-01-01

    Em 1987 o Instituto Nacional de Controle de Qualidade em Saúde iniciou o uso do Veneno Botrópico de Referência Nacional (VBRN), que é a primeira extração das serpentes B. jararaca recém-chegadas da natureza. Em 10 anos notou-se uma queda de 67,65% na recepção de serpentes ao Instituto Butantan (IB), e na distribuição geográfica, resultando em uma maior heterogeneidade na composição do VBRN. Assim, comparamos os venenos das serpentes nascidas em cativeiro (VP) do Laboratório de Herpetologia do...

  15. Acidente por serpentes do gênero Bothrops: série de 3.139 casos

    Directory of Open Access Journals (Sweden)

    Lindioneza Adriano Ribeiro

    1997-12-01

    Full Text Available Em avaliação dos prontuários médicos de 3.139 pacientes picados por serpentes do gênero Bothrops atendidos no Hospital Vital Brazil (HVB, de 1981 a 1990, observou-se maior acometimento do sexo masculino (75,7%. Em 1.412 casos (45,0% a serpente foi identificada, sendo 1.376 B. jararaca, 20 B. jararacussu, 11 B. neuwiedi, 2 B. moojeni, 2 B. alternatus e 1 B. pradoi. As regiões anatômicas mais comumente picadas foram: pé (47,5% e mão (21,3%. O torniquete foi realizado em 38,2% dos casos e sua freqüência diminuiu durante esse período (p Medical records of 3,139 patients bitten by Bothrops snakes and attended at Vital Brazil Hospital (HVB from 1981 to 1990 were reviwed. They were more frequent in males (75.7%. In 1,412 cases (45.0% the snake was classified by species, and 1,376 were B. jararaca, 20 B. jararacussu, 11 B. neuwiedi, 2 B. moojeni, 2 B. alternatus e 1 B. pradoi. The most frequent bitten anatomic regions were: foot (47.5% and hand (21.3%. Tourniquet was used in 38.2% of the cases and its frequency fell down during the study period (p < 0.05. The clinical features at the bite site were: pain (95.6%, swelling (95.4%, echimosis (56.1%, blisters (13.8%, necrosis (16.5%, and abscess (11.0%. Systemic manifestations were: bleeding (12.3%, acute renal failure (1.6%, and shock (0.7%. There were blood coagulation disorders in 1,730 (57.9% of the 2,990 cases. There were 21 amputations (0.7% and 9 deaths (0.3%. The average serum dose that was used in treatment fell down during the study period (p < 0.001.

  16. The genera Boiruna and Clelia (serpentes: pseudoboini in Paraguay and Argentina

    Directory of Open Access Journals (Sweden)

    Norman J. Scott Jr.

    2006-01-01

    to beyond the 40th parallel.As serpentes dos gêneros pseudoboinos Boiruna e Clelia, este último provavelmente não monofilético, estão distribuídas desde o sul da Argentina, Brasil e Uruguai até o centro do México. Seis de seus membros ocorrem no Paraguai e na Argentina: B. maculata, Clelia bicolor, C. clelia, C. plumbea, C. quimi, e C. rustica. Historicamente, existiram confusões entre as espécies de maior tamanho (B. maculata, C. clelia, C. plumbea e C. rustica e entre as espécies pequenas (C. bicolor e C. quimi. Todas as espécies, exceto C. rustica, possuem mudanças ontogenéticas na sua coloração. As espécies podem ser diferenciadas através do seu tamanho, cor, espinhos do hemipenis, e número de escamas loreais, supralabiais, e ventrais. A maior parte da diferenciação evolutiva em Boiruna e Clelia parecem ter ocorrido na região anterior da cabeça, pelo que mostram as diferentes proporções das escamas da região loreal. Boiruna maculata é a espécie de maior amplitude ecológica; é encontrada na maioria das formações vegetais existentes ao norte do paralelo 38 no centro da Argentina, ausente apenas na região de sedimentos deltaicos da província de Buenos Aires, Argentina, e nos amplos vales e colinas onduladas do leste do Paraguai. Clelia bicolor é mais comum nos vales dos rios Paraguai e Paraná, e com alguns registros na base dos Andes no norte da Argentina. Clelia clelia distribui-se ao longo do Rio Paraguai e do baixo Paraná, e quase todo o leste do Paraguai. Clelia plumbea aparentemente é parapátrida de C. clelia ao longo do rio Paraná no sudeste do Paraguai e na província de Misiones, Argentina. O extremo leste da distribuição de C. quimi limita-se com o extremo oeste da distribuição de C. bicolor na mesma região sem que, aparentemente, haja superposição. Não existe material de referência que prove a presença de Clelia rustica no Paraguai. Na Argentina, ela é uma espécie encontrada em áreas temperadas; ao norte

  17. Validation of main nuclear libraries used in thorium reactors using the Serpent code; Validação das principais bibliotecas nucleares utilizadas em reatores de tório com o código Serpent

    Energy Technology Data Exchange (ETDEWEB)

    Faga, Lucas J., E-mail: lucas.faga@usp.br [Universidade de São Paulo (USP), SP (Brazil). Instituto de Física; Stefani, Giovanni L. de, E-mail: giovanni.stefani@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil). Centro de Engenharia Nuclear; Santos, Thiago A. dos, E-mail: thiago.santos@ufabc.edu.br [Universidade Federal do ABC (UFABC), São Paulo, SP (Brazil)

    2017-07-01

    The purpose of this work is to validate the library of the Serpent standard database for systems containing U-233, U-235, Th-232, Pu-239 and Pu-240. The project will support the other projects of the newly created study group of Nuclear Engineering Center (CEN) of Instituto de Pesquisas Energéticas e Nucleares (IPEN), linked to the study of several types of reactors and their application in thorium cycles, a subject that gains more and more visibility, due to strong and potential promises of energy revolution. The results obtained at the end of the simulations were satisfactory, with the multiplication factors being effective close to 100 PCM of the values provided by the benchmarks, as expected for a validated library. The minimum distance between these values was 2 PCM and the maximum of 280 PCM. The final analysis demonstrates that the ENDF / B-VII library has validated nuclear data for the isotopes of interest and may be used in future thorium study group projects.

  18. Neutronic and thermal-hydraulic calculations for the AP-1000 NPP with the MCNP6 and SERPENT codes

    International Nuclear Information System (INIS)

    Stefani, Giovanni Laranjo; Maiorino, Jose R.; Santos, Thiago A.

    2015-01-01

    The AP-1000 is an evolutionary PWR reactor designed as an evolution of the AP-600 project. The reactor is already pre-licensed by NRC, and is considered to have achieved high standards of safety, possible short construction time and good economic competitiveness. The core is a 17x17 typical assembly using Zirlo as cladding, 3 different enrichment regions, and is controlled by boron, control banks, and burnable poison. The expected fuel final burnup is 62 MWD/ton U and a cycle of 18 months. In this paper we present results for neutronic and thermal-hydraulic calculations for the AP-1000. We use the MCNP6 and SERPENT codes to calculate the first cycle of operation. The calculated parameters are K eff at BOL and EOL and its variation with burnup and neutron flux, and reactivity coefficients. The production of transuranic elements such as Pu-239 and Pu-241, and burning fuel are calculated over time. In the work a complete reactor was burned for 450 days with no control elements, boron or burnable poison were considered, these results were compared with data provided by the Westinghouse. The results are compared with those reported in the literature. A simple thermal hydraulic analysis allows verification of thermal limits such as fuel and cladding temperatures, and MDNB. (author)

  19. Ação de venenos de serpentes brasileiras sôbre a alexina ou complemento

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    F. da Rocha Lagôa

    1947-06-01

    Full Text Available O autor estudou a ação inativante, sôbre o complemento de cobaia, alguns venenos de serpentes brasileiras pertencentes às famílias dos Elapideos e Crotalideos. Da primeira, foi utilizado veneno de Micrurus frontalis, da segunda, foram usados venenos de espécies pertencentes aos gêneros Crotalus (C. terrificus e Bothrops (B. atrox, B. neuwiedii, B. jararaca, B. ja-raracussú, B. cotiara e B. alternata. O venenos de M. frontalis e C. terri¬ficus se revelaram incapazes de inativar o complemento, ao passo que os diversos de Bothrops empregados se mostraram altamente inativantes, destruindo sempre o 4.° componente do complemento (C4, fração idêntica à afetada pela ação da amônea.The author shows in this paper the results of the inactivation of com¬plement or alexin by some Brazilian snakes venoms of the Elapideae and Cro¬talideae families. The venom of Micrurus frontalis (Elapideae family and of Crotalus terrificus (Crotalideae family did not destroy the complement; but the venoms of Bothrops generus (B. atrox, B. neuwiedii, B. jararaca, B. jararacussú, B. cotiara e B. alternata, (Crotalideae family are highly active in the inactivation complement, always destroing the fourth component, whichis exactly the same component that is detroyed by ammonia.

  20. Neutronic and thermal-hydraulic calculations for the AP-1000 NPP with the MCNP6 and SERPENT codes

    Energy Technology Data Exchange (ETDEWEB)

    Stefani, Giovanni Laranjo; Maiorino, Jose R.; Santos, Thiago A., E-mail: giovanni.laranjo@ufabc.edu.br, E-mail: joserubens.maiorino@ufabc.edu.br, E-mail: thiago.santos@ufabc.edu.br [Universidade Federal do ABC (CECS/UFABC), Santo Andre, SP (Brazil). Centro de Engenharia, Modelagem e Ciencias Sociais; Rossi, Pedro R., E-mail: pedro.russorossi@gmail.com [FERMIUM - Tecnologia Nuclear, Sao Paulo, SP (Brazil)

    2015-07-01

    The AP-1000 is an evolutionary PWR reactor designed as an evolution of the AP-600 project. The reactor is already pre-licensed by NRC, and is considered to have achieved high standards of safety, possible short construction time and good economic competitiveness. The core is a 17x17 typical assembly using Zirlo as cladding, 3 different enrichment regions, and is controlled by boron, control banks, and burnable poison. The expected fuel final burnup is 62 MWD/ton U and a cycle of 18 months. In this paper we present results for neutronic and thermal-hydraulic calculations for the AP-1000. We use the MCNP6 and SERPENT codes to calculate the first cycle of operation. The calculated parameters are K{sub eff} at BOL and EOL and its variation with burnup and neutron flux, and reactivity coefficients. The production of transuranic elements such as Pu-239 and Pu-241, and burning fuel are calculated over time. In the work a complete reactor was burned for 450 days with no control elements, boron or burnable poison were considered, these results were compared with data provided by the Westinghouse. The results are compared with those reported in the literature. A simple thermal hydraulic analysis allows verification of thermal limits such as fuel and cladding temperatures, and MDNB. (author)

  1. {sup 226}Ra concentrations in crayfish tissues, water, and sediments from the Serpent River Basin in Northeastern Ontario, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Alikhan, M.A. [Laurentian Univ., Sudbury, ON (Canada). Dept of Biology

    1996-12-31

    Lower Serpent River, as well as Elliot, McCarthy and McCabe lakes had highest {sup 226}Ra contamination, Chrisman, Quirke and Whiskey lakes a moderate one, Flack and Semiwhite lakes and the `distant` control, Lake Wanapitei, the lowest. {sup 226}Ra activity in Cambarus robustus tissues was directly related to their background levels. Thus, concentration coefficient (tissue/sediment concentrations) for {sup 226}Ra ranged from 0.53 to 0.74 in highly contaminated Elliot and McCarthy lakes, 0.28 to 0.59 in moderately contaminated Quirke and Whiskey lakes, and from 0.27 to 3.44 in least contaminated Semiwhite and Flack lakes. Among various organs analysed, exoskeleton showed the highest (43.04 - 90.69%) and the tail muscles the lowest (2.95 -17.14%) {sup 226}Ra activity. {sup 226}Ra concentrations in the alimentary canal were considered a part of the ambient environment as they had not been absorbed. 12 refs, 1 fig, 1 tab.

  2. Avaliação ultrassonográfica do aparelho reprodutor em serpentes vivíparas da família Boidae

    Directory of Open Access Journals (Sweden)

    Viviane C. Garcia

    2015-03-01

    Full Text Available A reprodução faz parte do ciclo de vida dos animais permitindo a perpetuação e a conservação das espécies. Em serpentes, existe uma escassez de informações técnicas a respeito do ciclo reprodutivo. Este estudo teve o objetivo de avaliar o aparelho reprodutivo por meio da ultrassonografia em serpentes vivíparas cativas da família Boidae, permitindo diagnosticar as diferentes fases reprodutivas. Foram avaliadas ultrassonograficamente onze serpentes adultas de quatro espécies da família Boidae: Eunectes murinus, Boa constrictor constrictor, Corallus hortulanus e Epicrates cenchria pertencentes ao acervo do Museu Biológico do Instituto Butantan, São Paulo Brasil. Para a avaliação ultrassonográfica, as serpentes foram contidas fisicamente com gancho herpetológico e depois manualmente por aproximadamente 15 minutos. A avaliação foi feita aplicando-se gel acústico sobre a pele e posicionando o transdutor na linha lateral-ventral direita e esquerda, em região medial do corpo em sentido crânio-caudal. O exame ultrassonográfico permitiu avaliar todo o ciclo reprodutivo nas serpentes. Nas avaliações ultrassonográficas das fêmeas pode-se definir as fases de desenvolvimento ovariano e ovidutal. Os folículos ovarianos durante a fase pré-vitelogênica foram visualizados como homogêneos e anecogênicos, em forma de "cacho de uva". Já na fase vitelogênica, os folículos estavam maiores e mais ecogênicos seguidos uns dos outros, como um "colar de pérolas". Quando não houve cópula, os folículos foram reabsorvidos dentro do ovário retornando a fase pré-vitelogênica. Na fase pós ovulatória foram visualizados três estágios bem definidos de desenvolvimento fetal dentro do oviduto: 1 logo após a ovulação (e fecundação, somente o vitelo foi visualizado; 2 o vitelo ocupava 60% e o feto 40% do ovo e 3 o feto estava formado e não havia vitelo. Nos machos, os testículos foram visualizados como uma imagem homogênea e

  3. Taxocenoses de serpentes em grupos fitofisionômicos de cerrado no Parque Nacional de Sete Cidades, Piracuruca, Piauí, Brasil

    OpenAIRE

    ROCHA, Wáldima Alves da

    2007-01-01

    Este trabalho teve como objetivo principal inventariar a fauna de serpentes do Parque Nacional de Sete Cidades, Piraracuruca, Piauí, Brasil, enfocando os seguintes aspectos: composição, riqueza e abundância de espécies nos seus diversos habitats, padrões de atividade diária, dieta, reprodução e comparação de composição com outras áreas estudadas por outros autores. Foram realizadas seis expedições ao Parque, entre setembro de 2005 e agosto de 2006, que totalizaram 120 dias de trabalho de c...

  4. Dieta e uso de habitat da jararaca-do-brejo, Mastigodryas bifossatus Raddi (Serpentes, Colubridade em domínio subtropical do Brasil Diet and habitat use of swamp racer snake, Mastigodryas bifossatus Raddi (Serpentes, Colubridae in subtropical domains of Brazil

    Directory of Open Access Journals (Sweden)

    Pedro T. Leite

    2007-01-01

    Full Text Available A serpente Mastigodryas bifossatus Raddi, 1820 é um grande colubrídeo neotropical que habita áreas abertas na América do Sul. Sua dieta é composta principalmente por anfíbios, mas inclui outros itens como mamíferos e lagartos. A dissecção de 224 espécimes desta serpente, provenientes dos estados do Rio Grande do Sul, Santa Catarina e Paraná, preservados em coleções herpetológicas do Brasil e um estudo de campo entre 1996 e 1998, fornecem informações sobre os hábitos alimentares e uso de habitat dessa serpente em domínio subtropical no Brasil. Essa serpente alimenta-se de anfíbios (80%, em sua maioria da família Leptodactylidae, mamíferos (10% e lagartos (2%. Foi verificada mudança ontogenética na dieta de M. bifossatus, o tamanho das presas ingeridas aumenta com o aumento de tamanho da serpente. Essa espécie ocorre principalmente em áreas abertas, algumas vezes perto de áreas antrópicas em domínio subtropical no Brasil.Mastigodryas bifossatus Raddi, 1820 is a large neotropical colubrid snake that inhabits open areas in South America. The diet is mainly composed by frogs, but it includes other items like mammals and lizards. The dissection of 224 specimens of this snake, proceeding from the states of Rio Grande do Sul, Santa Catarina and Paraná, stored in herpetological collections in Brazil and a field study between 1996 and 1998, provided information on dietary habits and habitat use of this snake in subtropical domains in Brazil. This snake eats mainly amphibians of the family Leptodactylidae (80%, mammals (10% and lizards (2%. There is ontogenetic diet shift in M. bifossatus, as the snake grows, the range of preys grows as well. M. bifossatus occur in open areas.

  5. Design of a Multi-Spectrum CANDU-based Reactor, MSCR, with 37-element fuel bundles using SERPENT code

    International Nuclear Information System (INIS)

    Hussein, M.S.; Bonin, H.W.; Lewis, B.J.; Chan, P.

    2015-01-01

    The burning of highly-enriched uranium and plutonium from dismantled nuclear warhead material in the new design nuclear power plants represents an important step towards nonproliferation. The blending of these highly enriched uranium and plutonium with with uranium dioxide from the spent fuel of CANDU reactors, or mixing it with depleted uranium would need a very long time to dispose of this material. Consequently, considering that more efficient transmutation of actinides occurs in fast neutron reactors, a novel Multi-Spectrum CANDU Reactor, has been designed on the basis of the CANDU6 reactor with two concentric regions. The simulations of the MSCR were carried out using the SERPENT code. The inner or fast neutron spectrum core is fuelled by different levels of enriched uranium oxides. The helium is used as a coolant in the fast neutron core. The outer or the thermal neutron spectrum core is fuelled with natural uranium with heavy water as both moderator and coolant. Both cores use 37- element fuel bundles. The size of the two cores and the percentage level of enrichment of the fresh fuel in the fast core were optimized according to the criticality safety of the whole reactor. The excess reactivity, the regeneration factor, radial and axial flux shapes of the MSCR reactor were calculated at different of the concentration of fissile isotope 235 U of uranium fuel at the fast neutron spectrum core. The effect of variation of the concentration of the fissile isotope on the fluxes in both cores at each energy bin has been studied. (author)

  6. Design of a Multi-Spectrum CANDU-based Reactor, MSCR, with 37-element fuel bundles using SERPENT code

    Energy Technology Data Exchange (ETDEWEB)

    Hussein, M.S.; Bonin, H.W.; Lewis, B.J.; Chan, P., E-mail: mohamed.hussein@rmc.ca, E-mail: bonin-h@rmc.ca, E-mail: lewis-b@rmc.ca, E-mail: Paul.Chan@rmc.ca [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, ON (Canada)

    2015-07-01

    The burning of highly-enriched uranium and plutonium from dismantled nuclear warhead material in the new design nuclear power plants represents an important step towards nonproliferation. The blending of these highly enriched uranium and plutonium with with uranium dioxide from the spent fuel of CANDU reactors, or mixing it with depleted uranium would need a very long time to dispose of this material. Consequently, considering that more efficient transmutation of actinides occurs in fast neutron reactors, a novel Multi-Spectrum CANDU Reactor, has been designed on the basis of the CANDU6 reactor with two concentric regions. The simulations of the MSCR were carried out using the SERPENT code. The inner or fast neutron spectrum core is fuelled by different levels of enriched uranium oxides. The helium is used as a coolant in the fast neutron core. The outer or the thermal neutron spectrum core is fuelled with natural uranium with heavy water as both moderator and coolant. Both cores use 37- element fuel bundles. The size of the two cores and the percentage level of enrichment of the fresh fuel in the fast core were optimized according to the criticality safety of the whole reactor. The excess reactivity, the regeneration factor, radial and axial flux shapes of the MSCR reactor were calculated at different of the concentration of fissile isotope {sup 235}U of uranium fuel at the fast neutron spectrum core. The effect of variation of the concentration of the fissile isotope on the fluxes in both cores at each energy bin has been studied. (author)

  7. A influência dos ritmos circadianos no metabolismo da serpente Bothrops jararaca (Serpentes, Viperidae - DOI: 10.4025/actascibiolsci.v30i3.5030 The influence of circadian rhythms on the metabolism of the snake Bothrops jararaca (Serpentes, Viperidae - DOI: 10.4025/actascibiolsci.v30i3.5030

    Directory of Open Access Journals (Sweden)

    José Geraldo Pereira da Cruz

    2008-10-01

    Full Text Available A atividade termorreguladora conduziu a uma busca extensiva para o entendimento das correlações entre as variáveis fisiológicas, incluindo as funções metabólicas e a temperatura corporal. Frequentes observações mostram que algumas serpentes podem se aquecer, sendo este aumento de temperatura independente da temperatura ambiente, indicando a termorregulação bem sucedida. Bothrops jararaca foram expostas a dois ambientes com diferentes temperaturas (20 e 30oC durante três semanas, sendo mensuradas a temperatura corporal e o consumo de oxigênio. O aumento da temperatura corporal e consumo de oxigênio de Bothrops jararaca ocorreram na fase de escuro do fotoperíodo, consistente para espécies noturnas. Entretanto, antecedendo a fase de escuro, as serpentes em 20oC apresentaram os níveis mais elevados durante o dia para temperatura corporal e consumo de oxigênio. Estes resultados indicam pela primeira vez que animais termodependentes podem controlar a temperatura corporal por meio de ritmos fisiológicos circadianos, semelhante aos observados em termoindependentes. Os ritmos circadianos permitem que os animais antecipem as mudanças no ambiente: parâmetros fisiológicos como a temperatura corporal e as reservas de energia ou sua mobilização podem ser ajustadas antes que as mudanças ambientais previstas ocorram realmente.The thermoregulatory activity has led to an extensive search for correlations between physiological variables, including metabolic functions, and the ideal level of body temperature. Snakes were also often seen basking, when their body temperatures were relatively independent of ambient temperature, indicating successful thermoregulation. Bothrops jararaca were exposed to two different ambient temperatures (20 and 30ºC over a time course of three weeks and oxygen consumption and body temperature were measured. The snakes exhibited a freerunning rhythm of body temperature. Metabolic rate was increased at the same

  8. Concentração de elementos traços em serpentes do litoral e da região serrana do Espírito Santo

    Directory of Open Access Journals (Sweden)

    Alexandra Frossard

    Full Text Available RESUMO: Os elementos químicos, em sua maioria, encontram-se em ciclos bioquímicos e geoquímicos fechados e em concentrações que não causam efeitos nocivos aos organismos. Contudo, ações antrópicas aceleradas promovem alterações ambientais, como o aumento no aporte de contaminantes. Com essas informações, o presente trabalho buscou caracterizar a presença aos elementos traços em duas espécies de serpentes comuns na região sudeste, Boa constrictor e Bothrops jararaca. Os exemplares de B. constrictor (n=18 foram provenientes de atropelamentos ocorridos no trecho da Rodovia ES-060 do Km 0 ao Km 67,5. Os exemplares de B. jararaca (n=18 foram capturados por fazendeiros na zona rural da região serrana do Espírito Santo. Foram analisados 1 grama de fragmento de rim, de espécimes necropsiados. Os rins coletados foram digeridos com mistura ácida (HNO3;HCl; 1:1 a 300oC, 40min e a quantificação de microelementos (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb e Zn foi realizada por espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES. Não foram observadas diferenças significativas entre machos e fêmeas, exceto para Cromo nas B. constrictor (p=0,03, com média de 1,6595 nas concentrações de Cr nas fêmeas e 0,2896 em machos. Contudo, quando foram comparadas as diferentes espécies de serpentes, diferentes concentrações foram encontradas, para todos os elementos determinados, com destaque para o Ferro com uma concentração de 106,2mg/g em B. constrictor e 120,3mg/g em B. jararaca, provavelmente por esses animais virem de áreas próximas à portos de minério de ferro. A concentração de Zinco em B. constrictor foi de 1261,8mg/g e em B. jararaca foi de 28,4mg/g. O presente estudo indica que as serpentes analisadas, que habitam as regiões da Grande Vitória e serrana do Espírito Santo apresentam elevadas concentrações dos microelementos Zn e Fe.

  9. The Descent of the Serpent: Using a Successful Ancient Solar Observatories Webcast from Chichen Itza to Highlight Space Weather Research

    Science.gov (United States)

    Hawkins, I.; Higdon, R.; Cline, T.

    2006-12-01

    Over the past seven years, NASA's Sun-Earth Connection Education Forum has sponsored and coordinated education and public outreach events to highlight NASA's heliophysics research and discoveries. Our strategy involves using celestial events, such as total solar eclipses and the Transit of Venus, as well as Sun-Earth Day during the March Equinox, to engage K-12 schools and the general public in space science activities, demonstrations, and interactions with space scientists. In collaboration with partners that include the Exploratorium and other museums, Ideum, NASA TV, NASA heliophysics missions, and others, we produce webcasts, other multi-media, and print resources for use by school and informal educators nation-wide and internationally. We provide training and professional development to K-12 educators, museum personnel, amateur astronomers, Girl Scout leaders, etc., so they can implement their own outreach programs taking advantage of our resources. A coordinated approach promotes multiple programs occurring each year under a common theme. As part of an Ancient Observatories theme in 2005, we have successfully featured solar alignments with ancient structures made by indigenous cultures that mark the equinoxes and/or solstices in cultural and historical parks in the Americas. In partnership with the Exploratorium, we produced broadcast-quality and webcast programming during the March equinox that shared heliophysics within a broad cultural context with formal and informal education audiences internationally. The program: "Descent of the Serpent" featured the light and shadow effect at sunset that takes place during the spring equinox at the Pyramid of El Castillo, in Chichén Itzá (México). This program made unique and authentic cultural connections to the knowledge of solar astronomy of the Maya, the living Mayan culture of today, and the importance of the Sun across the ages. We involved Sun-Earth Connection scientists, their missions, and research

  10. Transferência do Hepatozoon tupinambis, parasita do lagarto Tupinambis teguixin, para a serpente cascavel (Crotalus durissus terrificus, por intermédio do mosquito Culex fatigans

    Directory of Open Access Journals (Sweden)

    Samuel B. Pessôa

    1974-01-01

    Full Text Available Os autores obtiveram a transferência do Hepatozoon tupinambis (Laveran e Salibeni, 1909 parasita do lagarto Teiidae, Tupinambis teguixin, L., para a serpente cascavel, Crotalus durissus terrificus (Laur., alimentando-a com mosquitos experimentalmente infectados. o parasita mantém os seus caracteres morfológicos no animal receptor, nos limites do tempo observado (cerca de 100 dias. O ofídio receptor apresentou cistos esquizogônicos do fígado.The authors achieved a transfer of the Hepatozoon tupinambis (Laveran and Salibeni, 1909, a parasite of the Sauria: Tupinambis teguixin, L., to a rattlesnake of the species Crotalus durissus terrificus, feeding the latter with experimentally infected mosquitoes. The parasite maintained its morphological characteristics in the recepting animal throughout the whole observation period (about 100 days. Schizogonic cysts were found in the liver of the rattlesnake.

  11. Sarcophagidae and Calliphoridae related to Rhinella schneideri (Anura, Bufonidae, Bothrops moojeni (Reptilia, Serpentes and Mabuya frenata (Reptilia, Lacertilia carcasses in Brasília, Brazil

    Directory of Open Access Journals (Sweden)

    Roger Maia Dias Ledo

    2012-09-01

    Full Text Available Sarcophagidae and Calliphoridae related to Rhinella schneideri (Anura, Bufonidae, Bothrops moojeni (Reptilia, Serpentes and Mabuya frenata (Reptilia, Lacertilia carcasses in Brasília, Brazil. This paper presents a list of necrophagous insects associated with small size carrions of two reptiles and one amphibian, found in areas of riparian forests and Cerrado sensu stricto physiognomies in a Conservation Unit located in Brasilia, Distrito Federal. We found seven species of insects related to these carcasses, being five Sarcophagidae, one Calliphoridae and one Braconidae parasitoid wasp. Lucilia eximia and Peckia (Pattonella intermutans were the most abundant species in the study, corroborating with other studies that suggests that these species have specializations for colonization of small size animal carcasses.

  12. Padrões espaciais e conservação da diversidade de serpentes do bioma cerrado = Spatial patterns and biodiversity conservation of snakes from Cerrado biome

    OpenAIRE

    Larice de Fátima Couto; Levi Carina Terribile; José Alexandre Felizola Diniz-Filho

    2007-01-01

    Em geral, as tentativas para estabelecer áreas prioritárias para conservação no Cerrado têm sido baseadas em critérios subjetivos. No presente trabalho, foram utilizados dados macroecológicos de distribuição de 129 espécies de serpentes distribuídas em 181 células com 1o de latitude/longitude do Cerrado para analisar padrões espaciais na riqueza e propor uma estratégia de conservação para essas espécies. Verificou-se que as cinco variáveis ambientaisanalisadas explicaram apenas 34,65% da vari...

  13. Individual characterization of Bothrops alternatus Duméril, Bibron & Duméril venoms, according to their geographic distribution in Brazil (Serpentes, Viperidae)

    OpenAIRE

    Rocha, Marisa M. T. da; Furtado, Maria de F. D.

    2005-01-01

    Bothrops alternatus Duméril, Bibron & Duméril, 1854 é uma serpente de importância em saúde pública, com ampla distribuição geográfica, desde o Mato Grosso do Sul até o sudeste do Brasil, chegando até a Argentina e Uruguai, ocupando vários domínios morfoclimáticos. Neste trabalho investigou-se a variação do veneno de adultos de Bothrops alternatus, em função de sua distribuição geográfica no Brasil, comparativamente ao veneno elaborado sob a forma de "pool" desta espécie (veneno referência), q...

  14. Experimental ophitoxemia produced by the opisthoglyphous lora snake (Philodryas olfersii venom Ofitoxemia experimental produzida pelo veneno da serpente opistoglifa lora (Philodryas olfersii

    Directory of Open Access Journals (Sweden)

    Alexis Rodríguez-Acosta

    2006-04-01

    Full Text Available Several colubrid snakes produce venomous oral secretions. In this work, the venom collected from Venezuelan opisthoglyphous (rear-fanged Philodryas olfersii snake was studied. Different proteins were present in its venom and they were characterized by 20% SDS-PAGE protein electrophoresis. The secretion exhibited proteolytic (gelatinase activity, which was partially purified on a chromatography ionic exchange mono Q2 column. Additionally, the haemorrhagic activity of Philodryas olfersii venom on chicken embryos, mouse skin and peritoneum was demonstrated. Neurotoxic symptoms were demonstrated in mice inoculated with Philodryas olfersii venom. In conclusion, Philodryas olfersii venom showed proteolytic, haemorrhagic, and neurotoxic activities, thus increasing the interest in the high toxic action of Philodryas venom.Várias serpentes da família Colubridae produzem secreções orais venenosas. Neste trabalho, foi estudado o veneno coletado da presa posterior da serpente opistóglifa venezuelana Philodryas olfersii. Deferentes proteínas estavam presentes no veneno, sendo caracterizadas pela eletroforese de proteínas (SDS-PAGE a 20%. A secreção mostrou atividade proteolítica (gelatinase a qual foi parcialmente purificada em uma coluna de intercâmbio iônico (mono Q2. Adicionalmente, a atividade hemorrágica do veneno de Philodryas olfersii foi demonstrada em embriões de galinha, pele e peritônio de rato. Os sintomas neurológicos foram demonstrados em camundongos inoculados com veneno de Philodryas olfersii. Em conclusão, o veneno da Philodryas olfersii mostrou atividade proteolítica, hemorrágica, e neurotóxica, assim aumentando o interesse na elevada ação tóxica do veneno da Philodryas olfersii.

  15. An extended version of the SERPENT-2 code to investigate fuel burn-up and core material evolution of the Molten Salt Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Aufiero, M.; Cammi, A.; Fiorina, C. [Politecnico di Milano, Department of Energy, CeSNEF (Enrico Fermi Center for Nuclear Studies), via Ponzio, 34/3, I-20133 Milano (Italy); Leppänen, J. [VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT (Finland); Luzzi, L., E-mail: lelio.luzzi@polimi.it [Politecnico di Milano, Department of Energy, CeSNEF (Enrico Fermi Center for Nuclear Studies), via Ponzio, 34/3, I-20133 Milano (Italy); Ricotti, M.E. [Politecnico di Milano, Department of Energy, CeSNEF (Enrico Fermi Center for Nuclear Studies), via Ponzio, 34/3, I-20133 Milano (Italy)

    2013-10-15

    In this work, the Monte Carlo burn-up code SERPENT-2 has been extended and employed to study the material isotopic evolution of the Molten Salt Fast Reactor (MSFR). This promising GEN-IV nuclear reactor concept features peculiar characteristics such as the on-line fuel reprocessing, which prevents the use of commonly available burn-up codes. Besides, the presence of circulating nuclear fuel and radioactive streams from the core to the reprocessing plant requires a precise knowledge of the fuel isotopic composition during the plant operation. The developed extension of SERPENT-2 directly takes into account the effects of on-line fuel reprocessing on burn-up calculations and features a reactivity control algorithm. It is here assessed against a dedicated version of the deterministic ERANOS-based EQL3D procedure (PSI-Switzerland) and adopted to analyze the MSFR fuel salt isotopic evolution. Particular attention is devoted to study the effects of reprocessing time constants and efficiencies on the conversion ratio and the molar concentration of elements relevant for solubility issues (e.g., trivalent actinides and lanthanides). Quantities of interest for fuel handling and safety issues are investigated, including decay heat and activities of hazardous isotopes (neutron and high energy gamma emitters) in the core and in the reprocessing stream. The radiotoxicity generation is also analyzed for the MSFR nominal conditions. The production of helium and the depletion in tungsten content due to nuclear reactions are calculated for the nickel-based alloy selected as reactor structural material of the MSFR. These preliminary evaluations can be helpful in studying the radiation damage of both the primary salt container and the axial reflectors.

  16. Características biológicas e inmunológicas del veneno de Bothrops cotiara (Serpentes: Viperidae

    Directory of Open Access Journals (Sweden)

    Adolfo Rafael de Roodt

    2006-09-01

    Full Text Available Bothrops cotiara es una serpiente que se encuentra en la provincia de Misiones (Argentina, el Sur de Brasil y Paraguay. La información sobre las características clínicas de los accidentes por esta serpiente es muy escasa y existen pocos datos sobre su veneno y la capacidad neutralizante de las actividades tóxicas del mismo por antivenenos terapéuticos. En este trabajo se estudiaron características bioquímicas, actividades tóxicas y la reactividad inmunoquímica del veneno de B. cotiara. Seis antivenenos anti Viperinos Sudamericanos fueron estudiados frente a este veneno por el método ELISA y se probó la capacidad neutralizante de tres de estos frente a las actividades hemorrágica, necrotizante, procoagulante, trombina-símil, hemolítica indirecta y la potencia letal de veneno de ejemplares de B. cotiara de la provincia de Misiones. Los patrones cromatográficos y electroforéticos mostraron características similares a los de otros venenos de Bothrops. Las actividades tóxicas estuvieron dentro de los ámbitos descritos para los venenos botrópicos. Los seis antivenenos mostraron gran reactividad inmunoquímica por ELISA y las potencias neutralizantes de los tres estudiados fueron muy próximas para las actividades letal, hemorrágica, necrotizante, hemolítica indirecta, coagulante y trombina-símil. Los resultados de los estudios de neutralización indicarían que ante la mordedura de esta poco común especie de Bothrops, pueden usarse los diferentes tipos de antivenenos botrópicos o botrópico-crotálicos para uso terapéutico disponibles en esa región.Biological and immunological characteristics of the poison of Bothrops cotiara (Serpentes: Viperidae. Bothrops cotiara is a venomous snake sporadically found in the province of Misiones in Argentina, South of Brazil and Paraguay. Data on the clinics of the envenomation produced by its bite and on its venom are scarce. There is no information on the neutralizing capacity of the

  17. Non-venomous snake bite and snake bite without envenoming in a brazilian teaching hospital: analysis of 91 cases Acidentes por serpentes não-peçonhentas e acidentes por serpentes peçonhentas sem envenenamento em hospital universitário brasileiro: análise de 91 casos

    Directory of Open Access Journals (Sweden)

    Paulo Vitor Portella Silveira

    1992-12-01

    Full Text Available A retrospective survey of 473 cases of snake bite admitted to a Brazilian teaching hospital from 1984 to 1990 revealed 91 cases of bite without envenoming and/or caused by non-venomous snakes. In 17 of these cases the snake was identified, and one patient was bitten by a snake-like reptile (Amphisbaena mertensii. In 43 cases diagnosis was made on clinical grounds (fang marks in the absence of signs of envenoming. The other 30 cases were of patients who complained of being bitten but who did not show any sign of envenoming or fang mark. Most cases occurred in men (66;73%, in the 10-19 years age group (26;29%, in the lower limbs (51/74;69%, between 6 A. M. and 2 P.M. (49;61% and in the month of April (16; 18%. One patient bitten by Philodryas olfersii developed severe local pain, swelling and redness at the site of the bite, with normal clotting time. The patient bitten by Drymarcon corais was misdiagnosed as being bitten by a snake of the genus Bothrops, was given the specific antivenom, and developed anaphylaxis. One patient bitten by Sibynomorphus mikanii presented prolonged clotting time, and was also given antivenom as a case of Bothrops bite. Correct identification of venomous snakes by physicians is necessary to provide correct treatment to victims of snake bite, avoiding unnecessary distress to the patient, and overprescription of antivenom, which may eventually cause severe untoward effects.Um levantamento retrospectivo de 473 casos de acidentes ofídicos admitidos em um hospital-escola brasileiro de 1984 a 1990 revelou 91 casos sem envenenamento e/ou causados por serpentes não-peçonhentas. Em 17 casos a serpente foi identificada e um paciente foi mordido por um réptil que se assemelha às serpentes (Amphisbaena mertensii. Em 43 casos o diagnóstico foi clínico (sinal das presas na ausência de sinais de envenenamento. Os demais 30 casos foram de pacientes que se queixavam de terem sido mordidos mas que não apresentavam nem sinal de

  18. Branding Asklepios and the Traditional and Variant Serpent Symbol Display Among Health Professional Schools in the United States, Puerto Rico, and Canada: A Cross-Sectional Survey.

    Science.gov (United States)

    Hamann, Claus; Martelon, MaryKate

    2016-05-25

    History supports the staff and single serpent, the asklepian, as the symbol of healing and medicine, yet its confusion with the caduceus (a winged staff with two snakes wrapped around it) persists. No population-based information on serpent symbol use exists. To determine the prevalence of asklepian and caduceus display among Internet images of medical and health professional schools' emblems, and to compare asklepian and caduceus display between medical and health professional schools, examining the effects of school longevity and geographic location on symbol display. This cross-sectional survey examined Internet websites and Google Images associated with medical and other health professional schools in the United States, Puerto Rico, and Canada from 2013 to 2015. The primary outcome was display of a traditional or variant asklepian or caduceus among current and past emblems in Google Images. Odds ratios (ORs) and 95% confidence intervals for the comparison of medical versus other health professional schools were calculated by logistic regression. Differences among schools' longevity were assessed with Student's t-tests and linear regression. Among images of current and past emblems of 482 schools-159 medical schools and 323 health professional schools-107 (22.2%) emblems displayed only the traditional, and 205 (42.5%) any, asklepian. Adjusting for geographic region and longevity, medical schools were 59% less likely than health professional schools to display the traditional asklepian (OR 0.41, 95% CI 0.24-0.71, P=.001), and were 7.7 times more likely than health professional schools to display the traditional caduceus. Medical schools were 8% less likely than health professional schools to display any asklepian (OR 0.92, 95% CI 0.62-1.38, P=.70), and were 3.3 times more likely than health professional schools to display any caduceus. Schools' preference of the asklepian over the caduceus confirmed historical origins. Less asklepian and more caduceus display by

  19. Sarcophagidae and Calliphoridae related to Rhinella schneideri (Anura, Bufonidae, Bothrops moojeni (Reptilia, Serpentes and Mabuya frenata (Reptilia, Lacertilia carcasses in Brasília, Brazil Sarcophagidae e Calliphoridae associados às carcaças de Rhinella schneideri (Anura, Bufonidae, Bothrops moojeni (Reptilia, Serpentes e Mabuya frenata (Reptilia, Lacertilia em Brasília, Distrito Federal, Brasil

    Directory of Open Access Journals (Sweden)

    Roger Maia Dias Ledo

    2012-09-01

    Full Text Available Sarcophagidae and Calliphoridae related to Rhinella schneideri (Anura, Bufonidae, Bothrops moojeni (Reptilia, Serpentes and Mabuya frenata (Reptilia, Lacertilia carcasses in Brasília, Brazil. This paper presents a list of necrophagous insects associated with small size carrions of two reptiles and one amphibian, found in areas of riparian forests and Cerrado sensu stricto physiognomies in a Conservation Unit located in Brasilia, Distrito Federal. We found seven species of insects related to these carcasses, being five Sarcophagidae, one Calliphoridae and one Braconidae parasitoid wasp. Lucilia eximia and Peckia (Pattonella intermutans were the most abundant species in the study, corroborating with other studies that suggests that these species have specializations for colonization of small size animal carcasses.Sarcophagidae e Calliphoridae associados às carcaças de Rhinella schneideri (Anura, Bufonidae, Bothrops moojeni (Reptilia, Serpentes e Mabuya frenata (Reptilia, Lacertilia em Brasília, Distrito Federal, Brasil. Este trabalho apresenta uma lista de insetos decompositores associados a carcaças de pequeno porte de dois répteis e de um anfíbio, encontrados em áreas de matas de galeria e de cerrado sensu stricto em unidades de conservação do Distrito Federal. Foram encontradas sete espécies de insetos associados a essas carcaças, sendo cinco sarcofagídeos, um califorídeo e uma vespa parasitóide Braconidae. Lucilia eximia e Peckia (Pattonella intermutans foram as espécies mais abundantes, corroborando com outros estudos que sugerem que estas espécies apresentam especializações para a colonização de carcaças menores.

  20. The genus Atheris (Serpentes: Viperidae) in East Africa: phylogeny and the role of rifting and climate in shaping the current pattern of species diversity.

    Science.gov (United States)

    Menegon, M; Loader, S P; Marsden, S J; Branch, W R; Davenport, T R B; Ursenbacher, S

    2014-10-01

    Past climatic and tectonic events are believed to have strongly influenced species diversity in the Eastern Afromontane Biodiversity Hotspot. We investigated the phylogenetic relationships and historical biogeography of the East African genus Atheris (Serpentes: Viperidae), and explored temporal and spatial relationships between Atheris species across Africa, and the impact of palaeoclimatic fluctuations and tectonic movements on cladogenesis of the genus. Using mitochondrial sequence data, the phylogeny of East African species of Atheris shows congruent temporal patterns that link diversification to major tectonic and aridification events within East Africa over the last 15million years (my). Our results are consistent with a scenario of a delayed direct west-east colonisation of the Eastern Arc Mountains of Atheris by the formation of the western rift. Based on the phylogenetic patterns, this terrestrial, forest-associated genus has dispersed into East Africa across a divided route, on both west-southeasterly and west-northeasterly directions (a C-shaped route). Cladogenesis in the Eastern Arc Mountains and Southern Highlands of Tanzania corresponds to late Miocene and Plio-Pleistocene climatic shifts. Taxonomically, our data confirmed the monophyly of Atheris as currently defined, and reveal four major East African clades, three of which occur in discrete mountain ranges. Possible cryptic taxa are identified in the Atheris rungweensis and A. ceratophora clades. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Padrões espaciais e conservação da diversidade de serpentes do bioma cerrado = Spatial patterns and biodiversity conservation of snakes from Cerrado biome

    Directory of Open Access Journals (Sweden)

    Larice de Fátima Couto

    2007-01-01

    Full Text Available Em geral, as tentativas para estabelecer áreas prioritárias para conservação no Cerrado têm sido baseadas em critérios subjetivos. No presente trabalho, foram utilizados dados macroecológicos de distribuição de 129 espécies de serpentes distribuídas em 181 células com 1o de latitude/longitude do Cerrado para analisar padrões espaciais na riqueza e propor uma estratégia de conservação para essas espécies. Verificou-se que as cinco variáveis ambientaisanalisadas explicaram apenas 34,65% da variação na riqueza de serpentes do Cerrado. Para seleção de áreas prioritárias utilizando-se procedimentos de otimização, estabeleceu-se que 14 células são necessárias para representar todas as espécies pelo menos uma vez. Também foram incorporados ao modelo os padrões de ocupação humana no Cerrado, visando minimizar conflitos entre desenvolvimento e conservação, e neste caso as células concentram-se principalmente nosudoeste do bioma. Em função da falta geral de conhecimento sobre os padrões mais locais de distribuição de espécies no Cerrado, esses resultados devem ser considerados preliminares. De qualquer modo, o presente estudo, em escala biogeográfica, é importante para estabelecer estratégias metodológicas e para fornecer uma visão ampla dos padrões de diversidade e de que regiões seriam mais importantes para sua conservação. Until recently, the conservation of Cerrado has been neglected andattempts to establish conservation priorities were usually based on subjective criteria. In this paper, macroecological data of distribution of 129 species of snakes in the Cerrado were used to evaluate spatial patterns in species richness and to establish a system of potential areas that preserves all snake species in the region. The five environment variables used as predictors explained only 34.65% of the variance in species richness. In order to establishconservation priorities, optimization procedures were used

  2. Exercise ASKARI SERPENT: enabling clinical data collection during exercises and operations to support future contingency planning and assurance of category-based reporting systems.

    Science.gov (United States)

    Parsons, Iain T; Wheatley, R J; Carter, P

    2016-02-01

    Exercise ASKARI SERPENT (Ex AS) is a British Army exercise that provides primary healthcare (PHC) to Kenyan civilians in support of local health authorities. It is conducted in partnership with the Kenya Defence Force Medical Services (KDFMS). Accurate epidemiological data is critical in planning the exercise and for any future short-notice contingency operations in similar environments. This paper reports epidemiological data for Ex AS using a novel data collection system. PHC on Ex AS was delivered by trained and validated combat medical technicians (CMTs) using a set of Read-coded protocols. The CMTs were also directly supported and supervised by medical officers and nurses. A total of 3093 consultations were conducted over a 16-day period. Of these, 2707 (87.5%) consultations fell within the remit of the CMT protocols, with only 386 consultations (12.5%) being conducted exclusively by the medical officers or nurses. A Read-coded matrix built on CMT protocols is a simple and useful tool, particularly in civilian populations, for collecting morbidity data with the vast majority of conditions accounted for in the protocols. It is anticipated that such a system can better inform training, manning, medical material and pharmaceutical procurement than current category-based morbidity surveillance systems such as EPINATO (NATO epidemiological data). There is clear advantage to directly linking data capture to treatment algorithms. Accuracy, both in terms of numbers and condition, is likely improved. Data is also captured contemporaneously rather than after indeterminate time. Read coding has the added benefit of being an established electronic standard. In addition, the system would support traditional reporting methods such as EPINATO by providing increased assurance. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  3. Serpentes peçonhentas e ofidismo em Cruzeiro do Sul, Alto Juruá, Estado do Acre, Brasil Venomous snakes and ophidism in Cruzeiro do Sul, Alto Juruá, State of Acre, Brazil

    Directory of Open Access Journals (Sweden)

    Paulo Sérgio Bernarde

    2012-03-01

    Full Text Available Apesar da importância dos acidentes ofídicos na Saúde Pública, são relativamente poucas as pesquisas realizadas sobre esse tema no Brasil. Devido aos poucos estudos sobre ofidismo na Amazônia e especialmente no estado do Acre, trabalhos epidemiológicos são de grande relevância. Esse estudo apresenta a lista de serpentes peçonhentas e aspectos epidemiológicos dos acidentes ofídicos em Cruzeiro do Sul, região do Alto Juruá (Acre, verificando quais gêneros de serpentes são responsáveis pelos envenenamentos e aspectos que envolvem o acidente e o atendimento hospitalar. Os dados epidemiológicos foram coligidos a partir do SINAN (Sistema de Informações de Agravos de Notificação, no setor de vigilância epidemiológica do Hospital Regional do Juruá, no município de Cruzeiro do Sul. Sete espécies de serpentes peçonhentas foram registradas nesse município: três viperídeos (Bothrops atrox, Bothriopsis bilineata e Lachesis muta e quatro elapídeos (Micrurus hemprichii, M. lemniscatus, M. remotus and M. surinamensis. Durante o período de dois anos (agosto de 2007 a julho de 2009 foram registrados 195 casos de acidentes ofídicos. Cinquenta e um por cento dos acidentes foi classificado como laquético (Lachesis, seguido pelo botrópico (Bothrops e Bothriopsis com 38% e crotálico (Crotalus com 2%. Em 9% dos casos o gênero da serpente envolvida não foi informado. A maioria dos acidentes envolveu indivíduos adultos do gênero masculino em área rural, afetados principalmente nos membros inferiores. Os casos ocorreram mais frequentemente nos meses de novembro a abril, coincidindo com os maiores níveis pluviométricos. A maioria dos acidentes foi atribuída equivocadamente à serpente L. muta, tendo sido provavelmente causados por B. atrox.Despite the importance of accidents involving snakebites, research on this theme in Brazil is relatively rare, especially in the Amazon region. Due to the poor number of studies about ophidism

  4. Serpentes da área urbana de Cuiabá, Mato Grosso: aspectos ecológicos e acidentes ofídicos associados Snakes from the urban area of Cuiabá, Mato Grosso: ecological aspects and associated snakebites

    Directory of Open Access Journals (Sweden)

    Marcos André de Carvalho

    1998-10-01

    Full Text Available São apresentadas informações sobre as serpentes da área urbana do Município de Cuiabá, Mato Grosso, potencialmente causadoras de acidentes ofídicos. As informações estão baseadas em exemplares doados por populares ao Núcleo de Ofiologia Regional de Mato Grosso (Normat entre 1986 e 1993 e em registros efetuados pelo Centro de Informações Anti-Veneno (Ciave entre 1988 e 1993, que não fazem referência ao animal causador. Foram catalogadas 37 espécies de serpentes, em 25 gêneros e 3 famílias, com hábitos predominantemente diurnos, terrestres e com dietas baseadas em anfíbios e/ou lagartos. Dentre os 307 acidentes ofídicos registrados, 56% foram causados por serpentes sem interesse médico e 44% constituíram acidentes de importância médica. Cerca de 99% dos acidentes de importância médica foram atribuídos ao gênero Bothrops (Bothrops moojeni e Bothrops neuwiedi seriam as principais causadoras. Dentre as espécies sem interesse médico, Philodryas olfersii e Waglerophis merremii provavelmente foram as principais responsáveis pela maior parte dos acidentes.This study presents data on snakes recorded in the urban area of Cuiabá, Mato Grosso, Brazil. Sources of information included specimens captured by local residents (1986-1993 and turned over to the Mato Grosso Regional Ophiological Center (Normat, and data from the Anti-Venom Information Center (Ciave, regarding urban snakebites (1988-1993. Thirty-seven species of snakes from 25 genera and three families were recorded. Diurnal and terrestrial habits predominated, as well as a diet based on amphibians and/or lizards. From a total of 307 snakebites recorded, some 56% were of no clinical importance, caused by non-venomous snakes, whereas 44% were clinically relevant. Approximately 99% of the latter were attributed to vipers of the genus Bothrops, and especially the Bothrops moojeni and Bothrops neuwiedi species The colubrids Philodryas olfersii and Waglerophis merremii were

  5. Perfil eletroforético das proteínas séricas de serpentes Crotalus durissus terrificus (cascavel criadas em cativeiro Serum protein electrophoresis profile of the rattlesnake Crotalus durissus terrificus kept in captivity

    Directory of Open Access Journals (Sweden)

    Joandes Henrique Fonteque

    2009-06-01

    Full Text Available As serpentes peçonhentas dos gêneros Bothrops e Crotalus têm sido mantidas em cativeiro visando à extração de venenos para a produção de imunobiológicos. O conhecimento da fisiologia desses animais e as alterações na concentração de proteínas e suas frações séricas são importantes para a identificação precoce de importantes enfermidades que cursam com estados de hipoproteinemia e hiperproteinemia. O objetivo do trabalho foi determinar a concentração de proteína total e o perfil eletroforético das proteínas séricas de serpentes Crotalus durissus terrificus (cascavel criadas em cativeiro. Foram colhidas amostras de sangue da veia coccígea ventral de 21 serpentes adultas e sadias, divididas em dois grupos: Grupo 1 de 12 machos com peso médio de 588,89±193,55g, e Grupo 2 de nove fêmeas com peso médio de 708,33±194,04g. A proteína total sérica foi determinada pelo método de refratometria e a eletroforese em gel de agarose. Obtiveram-se valores da proteína total sérica (g/dL de 4,51±0,50 para machos e de 4,82±0,72 para fêmeas, e para machos e fêmeas de 4,64±0,61. Foram identificadas pela eletroforese quatro frações protéicas (g/dL: albumina, a, b, g-globulinas e calculada a relação albumina:globulina. As serpentes fêmeas apresentaram maiores valores para as variáveis, albumina e para a relação albumina/globulina (AG diferindo significativamente (PThe poisonous snakes of the genera Crotalus and Bothrops have been kept in captivity with the purpose of extracting poison for the production of immunobiological. Knowledge of the physiology of these animals and serum proteins concentration changes are important for early identification of major diseases which lead to states of hypoproteinemia and hyperproteinemia. The objective was to determine the concentration of total protein and serum protein electrophoresis profile of Crotalus durissus terrificus (rattlesnake in captivity. Blood samples were taken from

  6. Acidente vascular cerebral hemorrágico associado à acidente ofídico por serpente do gênero bothrops: relato de caso Hemorrhagic stroke related to snakebite by bothrops genus: a case report

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    Amanda Silva Machado

    2010-10-01

    Full Text Available Este trabalho tem como objetivo relatar um caso de acidente vascular cerebral hemorrágico, associado à acidente ofídico por serpente do gênero bothrops e hipertensão arterial sistêmica grave. Apesar do ofidismo botrópico ser frequente no Estado do Pará, tais associações são incomuns, necessitando de uma abordagem especializada e precoce, visando menores complicações.This research reports a clinical case of hemorrhagic stroke due to envenomation by bothrops snakebite associated with severe hypertension. Although bothrops snakebites are frequent in the State of Pará, such associations are uncommon, requiring specialized and early management to avoid severe complications.

  7. New S-box calculation approach for Rijndael-AES based on an artificial neural network

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    Jaime David Rios Arrañaga

    2017-11-01

    Full Text Available The S-box is a basic important component in symmetric key encryption, used in block ciphers to confuse or hide the relationship between the plaintext and the ciphertext. In this paper a way to develop the transformation of an input of the S-box specified in AES encryption system through an artificial neural network and the multiplicative inverse in Galois Field is presented. With this implementation more security is achieved since the values of the S-box remain hidden and the inverse table serves as a distractor since it would appear to be the complete S-box. This is implemented on MATLAB and HSPICE using a network of perceptron neurons with a hidden layer and null error.

  8. Are there co-occurrence patterns that structure snake communities in Central Brazil? Existem padrões de coocorrência que estruturam comunidades de serpentes no Brasil Central?

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    FGR. França

    2007-02-01

    Full Text Available The main factors that structure Neotropical animal communities have been the subject of discussion in ecology communities. We used a set of null models to investigate the existence of structure in snake communities from the Cerrado in Central Brazil in relation to the co-occurrence of species and guilds concerning specific resources. We used fragments (conservation units inside the Distrito Federal and neighbor municipalities. In spite of recent human colonization in the region from the end of the 1950’s, intense habitat modification and fragmentation has taken place. Sixty three snake species are present in the Distrito Federal. Co-occurrence analysis of species and guilds associated to snake diets and habitats suggested a lack of organization. The homogeneity of habitats in Central Brazil and the minor importance of ecological effects can lead to random arrangement.Os processos que levam à estruturação de comunidades animais neotropicais têm sido sujeito de ampla discussão em ecologia de comunidades. Usou-se um conjunto de modelos nulos para investigar a existência de estrutura em comunidades de serpentes presentes no Cerrado do Brasil Central, em relação à coocorrência de espécies e de guildas relacionadas a recursos específicos. As localidades utilizadas para as análises representam fragmentos de habitats dentro do Distrito Federal e em municípios vizinhos. Apesar da recente colonização humana da região, datada para o final da década de 50, a intensidade da modificação e fragmentação dos habitats no Brasil Central têm sido enorme. Sessenta e três espécies de serpentes estão presentes no Distrito Federal. As análises dos padrões de coocorrência tanto para as espécies quanto para guildas relativas à dieta e ao uso do ambiente sugeriram ausência de organização. A homogeneidade dos ambientes no Brasil Central e a baixa importância de efeitos ecológicos podem levar ao arranjo randômico.

  9. Padrões espaciais e conservação da diversidade de serpentes do bioma cerrado - DOI: 10.4025/actascibiolsci.v29i1.145 Spatial patterns and biodiversity conservation of snakes from Cerrado biome

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    Levi Carina Terribile

    2007-11-01

    Full Text Available Em geral, as tentativas para estabelecer áreas prioritárias para conservação no Cerrado têm sido baseadas em critérios subjetivos. No presente trabalho, foram utilizados dados macroecológicos de distribuição de 129 espécies de serpentes distribuídas em 181 células com 1o de latitude/longitude do Cerrado para analisar padrões espaciais na riqueza e propor uma estratégia de conservação para essas espécies. Verificou-se que as cinco variáveis ambientais analisadas explicaram apenas 34,65% da variação na riqueza de serpentes do Cerrado. Para seleção de áreas prioritárias utilizando-se procedimentos de otimização, estabeleceu-se que 14 células são necessárias para representar todas as espécies pelo menos uma vez. Também foram incorporados ao modelo os padrões de ocupação humana no Cerrado, visando minimizar conflitos entre desenvolvimento e conservação, e neste caso as células concentram-se principalmente no sudoeste do bioma. Em função da falta geral de conhecimento sobre os padrões mais locais de distribuição de espécies no Cerrado, esses resultados devem ser considerados preliminares. De qualquer modo, o presente estudo, em escala biogeográfica, importante para estabelecer estratégias metodológicas e para fornecer uma visão ampla dos padrões de diversidade e de que regiões seriam mais importantes para sua conservação.Until recently, the conservation of Cerrado has been neglected and attempts to establish conservation priorities were usually based on subjective criteria. In this paper, macroecological data of distribution of 129 species of snakes in the Cerrado were used to evaluate spatial patterns in species richness and to establish a system of potential areas that preserves all snake species in the region. The five environment variables used as predictors explained only 34.65% of the variance in species richness. In order to establish conservation priorities, optimization procedures were used

  10. Caracterização individual do veneno de Bothrops alternatus Duméril, Bibron & Duméril em função da distribuição geográfica no Brasil (Serpentes,Viperidae Individual characterization of Bothrops alternatus Duméril, Bibron & Duméril venoms, according to their geographic distribution in Brazil (Serpentes, Viperidae

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    Marisa M. T. da Rocha

    2005-06-01

    Full Text Available Bothrops alternatus Duméril, Bibron & Duméril, 1854 é uma serpente de importância em saúde pública, com ampla distribuição geográfica, desde o Mato Grosso do Sul até o sudeste do Brasil, chegando até a Argentina e Uruguai, ocupando vários domínios morfoclimáticos. Neste trabalho investigou-se a variação do veneno de adultos de Bothrops alternatus, em função de sua distribuição geográfica no Brasil, comparativamente ao veneno elaborado sob a forma de "pool" desta espécie (veneno referência, que inclui serpentes, em sua maioria, da região do estado de São Paulo. Foram analisadas as atividades letal, coagulante sobre o plasma, proteolítica sobre a caseína e miotóxica, bem como os padrões eletroforéticos de 61 amostras individuais de veneno contrapostas ao "pool". Os resultados mostraram que o veneno de B. alternatus é pouco ativo, comparativamente ao de outros Bothrops Wagler, 1824. A variação individual prevaleceu, não apresentando correlação com as áreas de distribuição geográfica e domínios morfoclimáticos, porém a atividade coagulante das amostras de veneno provenientes do nordeste da distribuição geográfica apresentaram-se menos ativas comparativamente às da porção central da distribuição. Os venenos provenientes das bordas da distribuição apresentaram ações proteolíticas e miotóxicas mais intensas, que estatisticamente não foram significativamente diferentes. As variações individuais prevaleceram.Bothrops alternatus Duméril, Bibron & Duméril, 1854 snakebites are an important public health problem in Brazil. Such snakes are found from Mato Grosso do Sul (central Brazil to southeastern Brazil, reaching even Argentina and Uruguay and thereby occupying different morphoclimatic domains. This work investigated venom variation occurring in adult specimens of B. alternatus specimens, according to their geographic distribution in Brazil. The standard venom pool (reference venom produced by

  11. Amblyomma rotundatum (Koch, 1844 (Acari: Ixodidae two-host life-cycle on Viperidae snakes Ciclo dioxênico em Amblyomma rotundatum (Koch, 1844 (Acari: Ixodidaeparasitando serpentes da família Viperidae

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    Daniel Sobreira Rodrigues

    2010-09-01

    Full Text Available Amblyomma rotundatum is an ixodid tick that infests ectothermic animals and reproduces exclusively by parthenogenesis. This tick has been frequently reported to infest reptiles and amphibians, under natural conditions and sometimes in captivity. It was described in Brazil and several other countries of South, Central and North America. Although many studies have reported aspects of its biology, none of them has used regularly either ophidian as hosts, or controlled temperature, humidity and luminosity for parasitic stages. The objective of this experiment was to study the life cycle of A. rotundatum feeding on Viperidae snakes under room controlled conditions at 27 ± 1 ºC temperature, 85 ± 10% relative humidity and 12:12 hours photoperiod for parasitic stages, and under B.O.D incubator conditions at 27 ± 1 ºC temperature, 85 ± 10% relative humidity and scotophase for non-parasitic stages. The total duration of the life cycle ranged from 56 to 163 days (mean of 105 days. Two-host life cycle was observed for most of the ixodid population studied.Amblyomma rotundatum é um carrapato da família Ixodidae, parasito de animais pecilotérmicos, e que se reproduz exclusivamente por partenogênese. Este carrapato é frequentemente relatado infestando répteis e anfíbios em condições naturais e, às vezes, em animais de cativeiro. Ele já foi relatado no Brasil e em vários outros países das Américas do Sul, Central e do Norte. Embora muitos estudos sobre sua biologia tenham sido publicados, nunca foram utilizados ofídios como hospedeiros e, tão pouco, foram realizados ensaios com os estádios parasitários sob condições controladas de temperatura, umidade e iluminação. O objetivo deste experimento foi estudar o ciclo biológico de A. rotundatum se alimentando em serpentes da família Viperidae sob condições ambientais controladas a 27 ± 1 ºC de temperatura, 85 ± 10% de umidade relativa do ar e 12:12 horas de fotoperíodo para est

  12. Postprandial thermogenesis in Bothrops moojeni (Serpentes: Viperidae

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    DR Stuginski

    2011-01-01

    Full Text Available Snakes that can ingest prey that are proportionally large have high metabolic rates during digestion. This great increase in metabolic rate (specific dynamic action - SDA may create a significant augment in the animal's body temperature. The present study investigated postprandial thermogenesis in Bothrops moojeni. Briefly, two groups of snakes were fed meals equivalent to 17 ± 3% and 32 ± 5% of their body weight and were observed for 72 hours, in which thermal images of each snake were taken with an infrared camera in a thermostable environment with a constant air temperature of 30°C. The results showed a significant increase in snake surface temperature, with a thermal peak between 33 and 36 hours after feeding. The meal size had a great impact on the intensity and duration of the thermogenic response. Such increase in temperature appears to be connected with the huge increase in metabolic rates during digestion of relatively large prey by snakes that feed infrequently. The ecologic implication of the thermogenic response is still not well understood; however, it is possible that its presence could affect behaviors associated with the snake digestion, such as postprandial thermophily.

  13. Snakes, rotators, serpents and the octahedral group

    International Nuclear Information System (INIS)

    Fieguth, T.

    1986-04-01

    Specific configurations of horizontal and vertical bending magnets are given that, when acting on the spin polarization vector of a particle beam, generate a group of 24 operators isomorphic to the group of rotational symmetries of a cube, known as the octahedral group. Some of these configurations have the feature of converting transversely polarized beams to longitudinally polarized beams (or vice versa) at the midpoint of the configuration for, in principle, all beam energies. Since the first order optical transfer matrix for each half of these configurations is nearly that of a drift region, the external geometry remains unchanged and midpoint dispersion is not introduced. Changing field strengths and/or polarities allows a configuration to serve as either a Snake(1/sup st/ or 2/sup nd/ kind) or a Rotator, where in both cases the spin polarization is longitudinal at the midpoint. In this conceptualization, emphasis has been placed on electron beams and, indeed, for these beams some practical applications can be envisioned. However, due to the relatively high integrated field strengths required, application of these concepts to proton beams may be more promising

  14. Snakebites by Bothrops spp in children in Campinas, São Paulo, Brazil Acidentes por serpentes do gênero Bothrops em crianças em Campinas, São Paulo, Brasil

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    Fábio BUCARETCHI

    2001-12-01

    Full Text Available From January, 1984 to March, 1999, 73 children under 15 y old (ages 1-14 y, median 9 y were admitted after being bitten by snakes of the genus Bothrops. Twenty-six percent of the children were classified as mild envenoming, 50.7% as moderate envenoming and 20.6% as severe envenoming. Two patients (2.7% showed no signs of envenoming. Most of the patients presented local manifestations, mainly edema (94.5%, pain (94.5% ecchymosis (73.9% and blisters (11%. Local and/or systemic bleeding was observed in 28.8% of the patients. Before antivenom (AV administration, blood coagulation disorders were observed in 60.7% (incoagulable blood in 39.3% of the 56 children that received AV only in our hospital. AV early reactions, most of which were considered mild, were observed in 44.6% of these cases (in 15/30 patients not pretreated and in 10/26 patients pretreated with hydrocortisone and histamine H1 and H2 antagonists. The main clinical complications observed were local infection (15.1%, compartment syndrome (4.1%, gangrene (1.4% and acute renal failure (1.4%. No deaths were recorded. There were no significant differences with regard to severity of envenoming versus the frequency of blood coagulation disorders among the three categories of envenoming (p = 0.75 or in the frequency of patients with AV early reactions between the groups that were and were not pretreated (p = 0.55. The frequency of local infection was significantly greater in severe cases (p De janeiro de 1984 a março de 1999, 73 crianças com menos de 15 anos de idade (1 a 14 anos, mediana = 9 anos foram admitidas após terem sido picadas por serpentes do gênero Bothrops. 26,0% das crianças foram classificadas como acidente leve, 50,7% como moderado e 20,6% como grave. Dois pacientes (2,7% não apresentaram sinais de envenenamento. A maioria dos pacientes apresentou manifestações locais, principalmente edema (94,5%, dor (94,5%, equimoses (73,9% e bolhas (11,0%. Sangramento local e/ou sist

  15. Comportamento alimentar e dieta de serpentes, gêneros Boiruna e Clelia (Serpentes, Colubridae

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    Pinto Carla da Costa

    2002-01-01

    Full Text Available Boiruna maculata Boulenger, 1896 and Clelia rustica (Cope, 1878 were observed in captivity feeding snakes and rodents, respectively. Both species have shown a similar procedure in relation to the prey. Major behavior differences among the two species were: rodents killed before being swallowed, and snakes were mostly swallowed alive; both species are able to find the rodents head faster than the snake one; the coils formed during constriction were also used to hold the prey, specially the last coil, while swallowing rodents. Informations on stomach contents was gathered by dissection of preserved specimens of Clelia clelia (Daudin, 1803 and C. plumbea (Wied, 1820 were also included in the dietary study. The majority of preys consisted on snakes and lizards. Other prey items were mammals and birds. Adult snakes prey relatively smaller animals than the juvenile snakes do.

  16. Interplay between tetrel and triel bonds in RC6H4CN⋯MF3CN⋯BX3 complexes: A combined symmetry-adapted perturbation theory, Møller-Plesset, and quantum theory of atoms-in-molecules study.

    Science.gov (United States)

    Yourdkhani, Sirous; Korona, Tatiana; Hadipour, Nasser L

    2015-12-15

    Intermolecular ternary complexes composed of: (1) the centrally placed trifluoroacetonitrile or its higher analogs with central carbon exchanged by silicon or germanium (M = C, Si, Ge), (2) the benzonitrile molecule or its para derivatives on one side, and (3) the boron trifluoride of trichloride molecule (X = F, Cl) on the opposite side as well as the corresponding intermolecular tetrel- and triel-bonded binary complexes, were investigated by symmetry-adapted perturbation theory (SAPT) and the supermolecular Møller-Plesset method (MP2) at the complete basis set limit for optimized geometries. A character of interactions was studied by quantum theory of atoms-in-molecules (QTAIM). A comparison of interaction energies and QTAIM bond descriptors for dimers and trimers reveals that tetrel and triel bonds increase in their strength if present together in the trimer. For the triel-bonded complex, this growth leads to a change of the bond character from closed-shell to partly covalent for Si or Ge tetrel atoms, so the resulting bonding scheme corresponds to a preliminary stage of the SN2 reaction. Limitations of the Lewis theory of acids and bases were shown by its failure in predicting the stability order of the triel complexes. The necessity of including interaction energy terms beyond the electrostatic component for an elucidation of the nature of σ- and π-holes was presented by a SAPT energy decomposition and by a study of differences in monomer electrostatic potentials obtained either from isolated monomer densities, or from densities resulting from a perturbation with the effective field of another monomer. © 2015 Wiley Periodicals, Inc.

  17. Chemosensory age discrimination in the snake Boa constrictor (Serpentes: Boidae

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    Marianne Gabirot

    2012-12-01

    Full Text Available Many snakes are able to use their chemosensory system to detect scent of conspecifics, which is important in many social contexts. Age discrimination based on chemical cues may be especially important to ensure access to sexually mature potential partners. In this study, we used 24 individual Boa constrictor snakes (12 adults mature and 12 non-mature individuals that had been captured in different areas of Ecuador, and were maintained in captivity at the Vivarium of Quito. We used tongue-flick experiments to examine whether these snakes were able to discriminate between scents from mature and non-mature individuals. Results showed that B. constrictor snakes used chemical cues to recognize conspecifics and that the scent of individuals of different ages elicited chemosensory responses of different magnitudes. The scents from adult conspecifics elicited the quickest and highest chemosensory responses (i.e., short latency times and high tongue-flick rates, although we did not find differential responses to scent of males and females. The magnitude of the responses was lower to scent of sub adult individuals, and then even lower to scent of juvenile snakes, but in all cases the scent of snakes was discriminated from a blank control. We discuss the potential chemical mechanisms that may allow age recognition and its implications for social and sexual behavior of this snake species.Muchas serpientes son capaces de usar su sistema quimiosensorial para detectar el olor de individuos coespecíficos, lo que es importante en muchos contextos sociales. La discriminación de la edad basada en señales químicas puede ser especialmente importante para asegurar el acceso a parejas potenciales que sean sexualmente maduras. En este estudio, usamos 24 individuos de una especie de boa (Boa constrictor (12 individuos adultos y 12 inmaduros que habían sido capturados en diferentes partes de Ecuador y eran mantenidos en cautividad el Vivarium de Quito. Usamos experimentos de protusiones linguales para examinar si esta serpiente es capaz de discriminar entre el olor de individuos maduros y no maduros. Los resultados mostraron que B. constrictor usa señales químicas para reconocer co-específicos y que el olor de individuos de distinta edad provoca respuestas quimiosensoriales de diferente magnitud. El olor de individuos adultos provocó las respuestas más rápidas y elevadas (esto es, tiempos de latencia más cortos y tasas más altas de protusiones linguales, aunque no encontramos diferencias en las respuestas a olores de machos y hembras. La magnitud de las respuestas fue más baja a olores de sub adultos, e incluso más baja a olor de juveniles, pero en todos los casos el olor de una serpiente era discriminado de un control no oloroso. Discutimos los posibles mecanismos químicos que pueden permitir esta discriminación de la edad y sus implicaciones para el comportamiento social y sexual de esta serpiente.

  18. Analyses of venom spitting in African cobras (Elapidae: Serpentes ...

    African Journals Online (AJOL)

    ... all four species. The low levels of variation in venom volume, coupled with the variation in venom dispersal pattern, suggests a complexity to the regulation of venom flow in spitting cobras beyond simply neuromuscular control of the extrinsic venom gland. Keywords: defensive behaviour, snake, teeth, Naja, Hemachatus ...

  19. Phylogeography of the Central American lancehead Bothrops asper (SERPENTES: VIPERIDAE)

    Science.gov (United States)

    Parkinson, Christopher L.; Daza, Juan M.; Wüster, Wolfgang

    2017-01-01

    The uplift and final connection of the Central American land bridge is considered the major event that allowed biotic exchange between vertebrate lineages of northern and southern origin in the New World. However, given the complex tectonics that shaped Middle America, there is still substantial controversy over details of this geographical reconnection, and its role in determining biogeographic patterns in the region. Here, we examine the phylogeography of Bothrops asper, a widely distributed pitviper in Middle America and northwestern South America, in an attempt to evaluate how the final Isthmian uplift and other biogeographical boundaries in the region influenced genealogical lineage divergence in this species. We examined sequence data from two mitochondrial genes (MT-CYB and MT-ND4) from 111 specimens of B. asper, representing 70 localities throughout the species’ distribution. We reconstructed phylogeographic patterns using maximum likelihood and Bayesian methods and estimated divergence time using the Bayesian relaxed clock method. Within the nominal species, an early split led to two divergent lineages of B. asper: one includes five phylogroups distributed in Caribbean Middle America and southwestern Ecuador, and the other comprises five other groups scattered in the Pacific slope of Isthmian Central America and northwestern South America. Our results provide evidence of a complex transition that involves at least two dispersal events into Middle America during the final closure of the Isthmus. PMID:29176806

  20. Chemosensory age discrimination in the snake Boa constrictor (Serpentes: Boidae

    Directory of Open Access Journals (Sweden)

    Marianne Gabirot

    2012-12-01

    Full Text Available Many snakes are able to use their chemosensory system to detect scent of conspecifics, which is important in many social contexts. Age discrimination based on chemical cues may be especially important to ensure access to sexually mature potential partners. In this study, we used 24 individual Boa constrictor snakes (12 adults mature and 12 non-mature individuals that had been captured in different areas of Ecuador, and were maintained in captivity at the Vivarium of Quito. We used tongue-flick experiments to examine whether these snakes were able to discriminate between scents from mature and non-mature individuals. Results showed that B. constrictor snakes used chemical cues to recognize conspecifics and that the scent of individuals of different ages elicited chemosensory responses of different magnitudes. The scents from adult conspecifics elicited the quickest and highest chemosensory responses (i.e., short latency times and high tongue-flick rates, although we did not find differential responses to scent of males and females. The magnitude of the responses was lower to scent of sub adult individuals, and then even lower to scent of juvenile snakes, but in all cases the scent of snakes was discriminated from a blank control. We discuss the potential chemical mechanisms that may allow age recognition and its implications for social and sexual behavior of this snake species.

  1. Fossorial snake genus Apostolepis from South America (Serpentes: Colubridae: Elapomorphinae

    Directory of Open Access Journals (Sweden)

    De Lema, Thales

    2001-07-01

    Full Text Available An update commented list of the snake genus Apostolepis from South America, with keys for identification of the species. They are fossorial snakes that present different coloration according their distribution: (a 7 to 3 dark stripes coloration, without light nuchal collar (if present, vestigial, with snout not projected beyond jaws - in Amazonian and enclaves within Caatinga domain; (b 5 dark striped dorsal pattern, snout projected, usually without white nuchal collars — from region of contact between Cerrado and Chaco domains; (c dorsal pattern coloration uniformly red, with nucho-cervical collars, snout usually projected — in Cerrado with dispersion to Chaco and Caatinga; (d 2 or none dark stripes dorsally, venter immaculate or with black blotches, snout projecting: (e an aberrant pattern with oblique black dorsal stripes, without collars, head black and snout projecting — one species in an enclave within Caatinga, with 17 rows of scales instead of 15.

  2. Uni-directional transport properties of a serpent billiard

    International Nuclear Information System (INIS)

    Horvat, Martin; Prosen, Tomaz

    2004-01-01

    We present a dynamical analysis of a classical billiard chain-a channel with parallel semi-circular walls, which can serve as a model for a bent optical fibre. An interesting feature of this model is the fact that the phase space separates into two disjoint invariant components corresponding to the left and right uni-directional motions. Dynamics is decomposed into the jump map, a Poincare map between the two ends of a basic cell, and the time function, travelling time across a basic cell of a point on a surface of section. The jump map has a mixed phase space where the relative sizes of the regular and chaotic components depend on the width of the channel. For a suitable value of this parameter, we can have almost fully chaotic phase space. We have studied numerically the Lyapunov exponents, time auto-correlation functions and diffusion of particles along the chain. As a result of the singularity of the time function, we obtain marginally normal diffusion after we subtract the average drift. The last result is also supported by some analytical arguments

  3. The rod and the serpent: history's ultimate healing symbol.

    Science.gov (United States)

    Antoniou, Stavros A; Antoniou, George A; Learney, Robert; Granderath, Frank A; Antoniou, Athanasios I

    2011-01-01

    The snake has served as a medical emblem for more than 2400 years, since its association with the ancient Greek god of medicine and healing, Asclepius, in the 4th century BC. Its symbolic background can be traced further back to the worship of gods of earth's blossom in ancient Egypt and earth-related deities of the archaic period of Greek antiquity. It is featured entwined around a staff of knowledge and wisdom in most anaglyphs depicting Asclepius. The snake was impressed in the Old and the New Testament as well as in the Christian tradition as a symbol of sin, rejuvenation, death, resurrection, asthenia, and therapy. It is postulated that the double-snake motif was reintroduced by Renaissance philosophers as a medical emblem due to the symbolic connections of Hermes with deliverance and redemption. However, its use during the last two centuries seems to lack substantial historical background. The historical, mythological, and traditional retrospection of the snake's symbolism validates its appropriateness in the health-care field.

  4. Circadian pattern of Bothrops moojeni in captivity (Serpentes: Viperidae

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    DR Stuginski

    2012-01-01

    Full Text Available Members of the subfamily Crotalinae are considered to be essentially nocturnal and most of the data about these snakes have been collected from the field. Information on how nutritional status affects the movement rate and activity patterns is a key point to elucidating the ecophysiology of snakes. In this study, we distributed 28 lancehead Bothrops moojeni into three groups under distinct feeding regimens after a month of fasting. Groups were divided as follows: ingestion of meals weighing (A 40%, (B 20%, or (C 10% of the snake body mass. Groups were monitored for five days before and after food intake and the activity periods and movement rates were recorded. Our results show that B. moojeni is prevalently nocturnal, and the activity peak occurs in the first three hours of the scotophase. After feeding, a significant decrease in activity levels in groups A and B was detected. The current results corroborate previous field data that describe B. moojeni as a nocturnal species with low movement rates. The relationship between motion and the amount of food consumed by the snake may be associated with its hunting strategy.

  5. Serpents in jars: the snake wine industry in Vietnam

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    R. Somaweera

    2010-10-01

    Full Text Available Exploitation of snakes in Vietnam takes place for different purposes, and among them the snake wine industry is prominent but has received far less attention than other dealings, such as the pet trade. Despite widespread commercialisation there is a general lack of information about this snake trade, which makes it difficult to evaluate its magnitude and impact on snake populations. This study documents the use of snakes in snake wine in four cities in Vietnam through surveys conducted in 127 locations selling snake wine in September 2009. This study provides a list of species used along with the number of individuals observed. While none of the species involved are listed in the IUCN Red List, seven species are listed in the Vietnam Red Data Book, of which five are regulated by CITES. On the other hand, the most abundant species used in the trade, Xenochrophis flavipunctatus, is not listed in any conservation document. The popularity and economic importance of snakes in the form of snake wine demonstrates the need for the development of sustainable use programs for these species.

  6. Reproductive biology of Echinanthera cyanopleura (Serpentes: Dipsadidae in southern Brazil

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    Noeli Zanella

    2010-02-01

    Full Text Available The reproductive cycles of snakes can be influenced by many factors, both biotic and abiotic, and information about these factors can contribute significantly to knowledge of the biology of many species. Here, we present data on the reproductive biology (body size, sexual dimorphism and female reproductive cycle of the forest-dwelling colubrid Echinanthera cyanopleura (Cope, 1885, based on analyses of 128 specimens preserved in collections and originating from the states of Paraná, Santa Catarina, and Rio Grande do Sul in southern Brazil. The snout-vent length of females was significantly greater than in males. The tail length of mature females was greater than in males, although this difference was not significant. Vitellogenesis occurs from August to December and eggs were found in greater frequency from October through December. Juveniles were found in larger numbers beginning in February, indicating that recruitment occurs from January to April. The reproductive cycle of this species is seasonal, which is usual for oviparous colubrids of temperate areas of Brazil.

  7. Una nueva coral falsa del género Scaphiodontophis (Serpentes: Colubridae de Colombia Una nueva coral falsa del género Scaphiodontophis (Serpentes: Colubridae de Colombia

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    Roze Janis A.

    1969-06-01

    Full Text Available Scaphiodontophis dugandi new species is described from northwestern Colombia. It differs from all the other species of this genus in having the grayish (buffy to light ochraceous in life coloration intercalated between the banded patterns on the anterior part of the body and on the tail, and in having a low number of maxillary teeth: 39 to 41 (as compared to 43 to 56 in the others.  A provisional key for the recognized forms of the genus Scaphiodontophis is offered although the relationships of several forms are unclear at this stage. Scaphiodontophis dugandi new species is described from northwestern Colombia. It differs from all the other species of this genus in having the grayish (buffy to light ochraceous in life coloration intercalated between the banded patterns on the anterior part of the body and on the tail, and in having a low number of maxillary teeth: 39 to 41 (as compared to 43 to 56 in the others.  A provisional key for the recognized forms of the genus Scaphiodontophis is offered although the relationships of several forms are unclear at this stage.

  8. Osteología craneal del género Philodryas (Serpentes: Colubridae

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    Lobo, Fernando

    1994-01-01

    Full Text Available We studied the skulls of eleven species of Philodryas. The skull of Philodryas patagoniensis is described, and some characters that show interspecific variation are recognized. These characters are used for phylogenetic inferences. We obtained three trees using Hennig86. The pair of sister species wich is presented in the three cladograms is P. mattogrossensis - P. varius: in only ene tree: P. buroni - P. burmeisteri.

  9. [Sequencing and analysis of the complete mitochondrial genome of the King Cobra, Ophiophagus hannah (Serpents: Elapidae)].

    Science.gov (United States)

    Chen, Nian; Lai, Xiao-Ping

    2010-07-01

    We obtained the complete mitochondrial genome of King Cobra(GenBank accession number: EU_921899) by Ex Taq-PCR, TA-cloning and primer-walking methods. This genome is very similar to other vertebrate, which is 17 267 bp in length and encodes 38 genes (including 13 protein-coding, 2 ribosomal RNA and 23 transfer RNA genes) and two long non-coding regions. The duplication of tRNA-Ile gene forms a new mitochondrial gene rearrangement model. Eight tRNA genes and one protein genes were transcribed from L strand, and the other genes were transcribed genes from H strand. Genes on the H strand show a fairly similar content of Adenosine and Thymine respectively, whereas those on the L strand have higher proportion of A than T. Combined rDNA sequence data (12S+16S rRNA) were used to reconstruct the phylogeny of 21 snake species for which complete mitochondrial genome sequences were available in the public databases. This large data set and an appropriate range of outgroup taxa demonstrated that Elapidae is more closely related to colubridae than viperidae, which supports the traditional viewpoints.

  10. "suurte autodega veetakse surma..." : [luuletused] / [Mesikepp, Indrek] François Serpent

    Index Scriptorium Estoniae

    Serpent, François, pseud., 1971-

    2001-01-01

    Sisu: "suurte autodega veetakse surma..." ; "need pole Sinu käed..." ; reliktid jääs ; "kusagil soolased tydrukud..." ; "vaba nagu prygi tuule käes..." ; "nyyd kõik kohad ja ajad..." ; Eestimaa ; "päikeses põlenud põllud..." ; Eestimaa kohal on armastus

  11. Variação entre filhotes de representantes do complexo Bothrops newied (Serpentes, Viperidae, Crotalinae

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    Vinícius Xavier

    2002-01-01

    Full Text Available External morphological characters of 141 young specimens (69 males and 72 femalesof the Bothrops newied complex were analyzed. Regression analysis was used in the study of morphometric characters and principal components analysis was used in the study of meristic and qualitative characters. Sexual dimorphism was confirmed in the meristic and morphometric characters. Males showed higher counts of subcaudals and longer tails. Females showed eventually higher number of ventrals and dorsal rows, and larger heads. Six different drawing patterns were diagnosed and can indicate the existence of different species. Ontogenetic variation was described.

  12. Review of the geographic distribution of Micrurus decoratus (Jan, 1858 (Serpentes: Elapidae

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    Rodrigo Castellari Gonzalez

    2014-08-01

    Full Text Available Micrurus decoratus (Jan, 1858 is a poorly known species of coral snake, with a controversial history concerning its geographical range. The lack of consensus among researchers, since its original description, is largely due to the reporting of erroneous localities in publications. Herein we present the geographical range for the species based on the review of 184 records from 67 different municipalities in Brazil, including two new records for the state of Espírito Santo, extending its distribution to ca. 300 km northward from the previous northernmost locality. We also comment on doubtful records for the states of Rio Grande do Sul and Bahia, which contain no accurate data. We restrict the occurrence of Micrurus decoratus to the Atlantic Rainforest, with elevation range from 400 up to 1,600 m in the Brazilian states of Santa Catarina, Paraná, São Paulo, Rio de Janeiro, Minas Gerais and Espírito Santo.

  13. A survey of the southernmost representatives of the tricolor species group, genus Phalotris (Serpentes, Colubridae

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    Geraldo C. Leynaud

    2005-12-01

    Full Text Available Colubrid snakes of the South American genus Phalotris are difficult to detect because of their secretive habits, and thus they are poorly represented in collections. The species Phalotris cuyanus and P. tricolor, the southernmost representatives of the tricolor species group, were studied to determine the limits of intraspecific variation of P. cuyanus and to consolidate the taxonomic relationship between both species, the phenetically and geographically closest members in the group. The distribution of selected external characters (cephalic, ventral and subcaudal scales, coloration pattern, width of white and black collars, and hemipenis morphology were analyzed. Comparative data on the other members of the group, P. mertensi and P. matogrossensis, are briefly discussed. Males of P. cuyanus have a higher number of ventral scales than males of P. tricolor (mean of 220.3 vs. 204.6. Cephalic melanism varies among individuals and does not have discriminant orgeographic value for this species group. The white nuchal collar may partially cover the parietal scales in the four species. The black collar is moderately narrow in P. cuyanus, but it can be up to 12 scales wide in P. tricolor. Vertebral dotting is neither constant nor exclusive of any species. The four species of the group are wellcharacterized by combinations of character states for each one. We suggest considering to P. cuyanus as an evolutionary species typical of the Monte biogeographic province.

  14. Reproductive cycle of the salmon-bellied racer, Mastigodryas melanolomus (Serpentes, Colubridae, from Costa Rica

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    Stephen R. Goldberg

    2006-12-01

    Full Text Available The purpose of this paper is to present new information on the reproductive cycle of M. melanolomus from Costa Rica based onhistological examination of gonadal material from museum specimens. The first information on the timing of the testicular cycle is alsopresented.

  15. Reproductive biology and diet of Liophis poecilogyrus poecilogyrus (Serpentes, Colubridae from southeastern Brazil

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    Roberta R. Pinto

    2004-09-01

    Full Text Available We describe the reproductive pattern and the diet of Liophis poecilogyrus poecilogyrus based on examination of museum specimens.The snake has an aseasonal reproductive pattern, suggesting multiple clutches during a year. Females are larger than males when sexual maturity is reached. Clutch size ranges from six to 15 eggs. The diet of Liophis poecilogyrus poecilogyrus is composed of anurans, and there are no a foraging decrease during the clutching season.

  16. Reproductive biology and food habits of Pseudoboa nigra (Serpentes: Dipsadidae from the Brazilian cerrado

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    Renata de Paula Orofino

    2010-07-01

    Full Text Available Herein we provide data on body size, sexual size dimorphism,reproductive cycle, and food habits of the pseudoboini snake Pseudoboa nigra, which is distributed mainly in central South America throughout the Cerrado domain. Based on dissections of 147 preserved specimens, it is shown that females attain, and mature at,larger body sizes than males. There is no significant sexual dimorphism in head length, but males have longer tails relative to their body sizes. Vitellogenesis, egg-laying, and sperm production occur throughout the year, but males do not exhibit long-term sperm storage. The main prey of P. nigra is lizards; there is no evidence of ontogenetic change or sex differences in the diet of this species.

  17. Leptophis santamartensis (Serpentes, Colubridae), a junior synonym of Leptophis ahaetulla occidentalis

    Science.gov (United States)

    Albuquerque, Nelson R.; de Passos, Paulo; Gotte, Steve W.

    2012-01-01

    Leptophis santamartensis, known only from Sierra Nevada de Santa Marta, Colombia, is one of the more poorly known species of the genus Leptophis. The characters used for its diagnosis largely overlap with those of other Leptophis, mainly with Leptophis ahaetulla occidentalis, the only other Leptophis known to occur in the Sierra Nevada de Santa Marta. A detailed comparison of L. a. occidentalis with the two known specimens of L. santamartensis leads to the conclusion that the latter should be relegated to the synonymy of the former.

  18. The local and the global: Gina Nahai and the taking up of serpents and stereotypes

    OpenAIRE

    Yousaf, N

    2007-01-01

    Region, home and transnational migration are explored in terms of the transcultural complexities that reverberate through Iranian American Gina Nahai's Sunday's Silence. Nahai grapples with stereotypes that attach to the Holiness churches in the east Tennessee region of Appalachia. This essay argues that the novel's politics rest on the intersubjectivity of strangers as bound into a metaphysics of desire. It is through this paradigm that Nahai writes against the reductive association of “mino...

  19. Shedding light on serpent sight: the visual pigments of henophidian snakes.

    Science.gov (United States)

    Davies, Wayne L; Cowing, Jill A; Bowmaker, James K; Carvalho, Livia S; Gower, David J; Hunt, David M

    2009-06-10

    The biologist Gordon Walls proposed his "transmutation" theory through the 1930s and the 1940s to explain cone-like morphology of rods (and vice versa) in the duplex retinas of modern-day reptiles, with snakes regarded as the epitome of his hypothesis. Despite Walls' interest, the visual system of reptiles, and in particular snakes, has been widely neglected in favor of studies of fishes and mammals. By analyzing the visual pigments of two henophidian snakes, Xenopeltis unicolor and Python regius, we show that both species express two cone opsins, an ultraviolet-sensitive short-wavelength-sensitive 1 (SWS1) (lambda(max) = 361 nm) pigment and a long-wavelength-sensitive (LWS) (lambda(max) = 550 nm) pigment, providing the potential for dichromatic color vision. They also possess rod photoreceptors which express the usual rod opsin (Rh1) pigment with a lambda(max) at 497 nm. This is the first molecular study of the visual pigments expressed in the photoreceptors of any snake species. The presence of a duplex retina and the characterization of LWS, SWS1, and Rh1 visual pigments in henophidian snakes implies that "lower" snakes do not provide support for Walls' transmutation theory, unlike some "higher" (caenophidian) snakes and other reptiles, such as geckos. More data from other snake lineages will be required to test this hypothesis further.

  20. A Case Study in Byzantine Dragon-Slaying: Digenes and the Serpent

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    Christopher Livanos

    2011-03-01

    Full Text Available The Byzantine epic Digenes Akrites has similarities with ancient and medieval Iranian traditions that, in consideration of the epic’s Eastern settings, suggest Iranian influences. Digenes resembles dragon-slaying heroes of other Indo-European traditions. He also resembles the Irish hero Cú Chulainn in that he is not psychologically fit to live in the midst of the community that depends on his protection. Freudian readings of Digenes’ encounters with the dragon and the Amazon Maximou are proposed.

  1. Pre-Modern Bosom Serpents and Hippocrates' Epidemiae 5: 86: A Comparative and Contextual Folklore Approach

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    Davide Ermacora

    2016-03-01

    Full Text Available A short Hippocratic passage (Epidemiae 5: 86 might constitute the earliest Western surviving variant of the well-known narrative and experiential theme of snakes or other animals getting into the human body (motif B784, tale-type ATU 285B*. This paper aims: 1 to throw light on this ancient passage through a comparative folkloric analysis and through a philological-contextual study, with reference to modern and contemporary interpretations; and 2 to offer an examination of previous scholarly enquiries on the fantastic intrusion of animals into the human body. In medieval and post-medieval folklore and medicine, sleeping out in the field was dangerous: snakes and similar animals could, it was believed, crawl into the sleeper’s body through the ears, eyes, mouth, nostrils, anus and vagina. Comparative material demonstrates, meanwhile, that the thirsty snake often entered the sleeper’s mouth because of its love of milk and wine. I will argue that while Epidemiae 5: 86 is modelled on this long-standing legendary pattern, for which many interesting literary pre-modern (and modern parallels exist, its relatively precise historical and cultural framework can be efficiently analysed. The story is embedded in a broad set of Graeco-Roman ideas and practices surrounding ancient beliefs about snakes and attitudes to the drinking of unmixed wine.

  2. Biological and immunological characteristics of the poison of Bothrops cotiara (Serpentes: Viperidae)

    International Nuclear Information System (INIS)

    Roodt, Adolfo Rafael de; Dolab, Jorge Adrian; Manzanelli, Marcelo Victor; Pineiro, Nicolas; Estevez, Judith; Paniagua, Jorge Francisco; Urs Vogt, Alejandro

    2006-01-01

    Bothrops cotiara is a venomous snake sporadically found in the province of Misiones in Argentina, South of Brazil and Paraguay. Data on the clinics of the poisoning produced by its bite and on its venom are scarce. There is no information on the neutralizing capacity of the antivenoms available. In this study, the lethal potency, hemorrhagic, necrotizing, coagulant and thrombin-like, defibrinogenasing, indirect hemolytic and fibrinolytic activities of the venom of B. cotiara specimens from the province of Misiones were determined. The toxic activities were within the range of those described for the other Bothrops species from Argentina, and the electrophoretic and chromatographic studies showed similarities with those described for the other bothropic venoms. The immunochemical reactivity of six South American anti Viper antivenoms (ELISA) have a strong reactivity with all the antivenoms studied. The neutralizing capacity of three of these therapeutic antivenoms against the lethal potency and hemorrhagic, necrotizing, coagulant, thrombin-like and hemolytic activities showed a very close neutralizing capacity. Our data strongly suggest that the antivenoms for therapeutic use available in this area of South America are useful to neutralize the toxic and enzymatic activities of the venom of this uncommon specie of Bothrops. (author) [es

  3. Death of Boa constrictor amarali (serpentes, boidae after ingestion of a tree porcupine (rodentia

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    A. L. Cherubini

    2003-01-01

    Full Text Available The objective of this paper is to report the death of a Boa constrictor amarali after ingestion of a tree porcupine. The animal was donated to the Center for the Study of Venoms and Venomous Animals (CEVAP/UNESP - and died in captivity. At necropsy, spine-like structures were observed in the stomach serosa and vicinity, and the stomach mucosa showed an intense reddish area, suggesting inflammation. The analysis of the spine-like structure revealed that they were tree porcupine spines. The feeding habits and inexperience of this Boa constrictor amarali in selecting its prey may have been be responsible for its death.

  4. Is the population of Crotalus durissus (Serpentes, Viperidae) expanding in Brazil?

    OpenAIRE

    Duarte, Marcelo Ribeiro; Menezes, Frederico Alcântara

    2013-01-01

    Crotalus durissus are found from Mexico to northern Argentina in a highly disjunct distribution. According to some studies, this species is prone to occupy areas disturbed by human activities and floods comprise a plausible method of dispersal as inferred for some North American rattlesnakes. Based on the literature, it seems plausible that Crotalus durissus expanded their natural distribution in Brazil due to floods, but only in a few municipalities in Rio de Janeiro State. Data entries of B...

  5. DISCOVERY OF THE MADAGASCAR SERPENT-EAGLE, EUTRIORCHIS ASTUR, IN CENTRAL AND SOUTHEASTERN MADAGASCAR. (U915543)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  6. Molecular systematics and undescribed diversity of Madagascan scolecophidian snakes (Squamata: Serpentes).

    Science.gov (United States)

    Nagy, Zoltán T; Marion, Angela B; Glaw, Frank; Miralles, Aurélien; Nopper, Joachim; Vences, Miguel; Hedges, S Blair

    2015-11-10

    We provide an updated molecular phylogenetic analysis of global diversity of typhlopid and xenotyphlopid blindsnakes, adding a set of Madagascan samples and sequences of an additional mitochondrial gene to an existing supermatrix of nuclear and mitochondrial gene segments. Our data suggest monophyly of Madagascan typhlopids, exclusive of introduced Indotyphlops braminus. The Madagascar-endemic typhlopid clade includes two species previously assigned to the genus Lemuriatyphlops (in the subfamily Asiatyphlopinae), which were not each others closest relatives. This contradicts a previous study that described Lemuriatyphlops based on a sequence of the cytochrome oxidase subunit 1 gene from a single species and found this species not forming a clade with the other Malagasy species included. Based on our novel phylogenetic assessment we include all species in this endemic typhlopid clade in the genus Madatyphlops and in the subfamily Madatyphlopinae and consider Lemuriatyphlops as junior synonym. Within Madatyphlops, we identify several candidate species. For some of these (those in the M. arenarius complex), our preliminary data suggest sympatric occurrence and morphological differentiation, thus the existence of undescribed species. We also comment on the genus-level classification of several non-Madagascan typhlopids. We suggest that African species included in Madatyphlops (Afrotyphlops calabresii, A. cuneirostris, A. platyrhynchus, and Rhinotyphlops leucocephalus) should not be included in this genus. We furthermore argue that recent claims of Sundatyphlops, Antillotyphlops, and Cubatyphlops being "undiagnosable" or "not monophyletic" were based on errors in tree reconstruction and failure to notice diagnostic characters, and thus regard these three genera as valid.

  7. Seasonal, daily activity, and habitat use by three sympatric pit vipers (Serpentes, Viperidae) from southern Brazil.

    Science.gov (United States)

    Rocha, Marcelo C; Hartmann, Paulo A; Winck, Gisele R; Cechin, Sonia Z

    2014-04-25

    Viperid snakes are widely distributed in the South America and the greater distribution range of the family is found at the Crotalinae subfamily. Despite the abundance of this snakes along their geographic distribution, some ecological aspects remain unknown, principally at subtropical areas. In the present study, we evaluated the activity (daily and seasonal) and the use of the habitat by Bothrops diporus, B. jararaca and B. jararacussu, in an Atlantic Forest area at southern Brazil. We observed higher incidence of viperid snakes during the months with higher temperatures, while no snakes were found during the months with lower temperatures. The data suggest the minimum temperature as environmental variable with the greatest influence on the seasonal activity of this species. Considering the daily activity, we observed a tendency of snakes to avoid the warmest hours. Bothrops jararacussu tend to avoid open areas, being registered only inside and at the edges of the forest. We compared our results with previous studies realized at tropical areas and we suggest the observed seasonal activity as an evolutive response, despite the influence of the different environmental variables, according to the occurence region.

  8. Intraspecific variation of Bothrops pubescens (cope, 1869 venom in Uruguay (serpentes: viperidae

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    V. Morais

    2006-01-01

    Full Text Available In Uruguay, there was no information about the variations degree in Bothrops pubescens venoms until the present work, in which we investigated intraspecific venom variation using polyacrylamide gel electrophoresis (SDS-PAGE. We found some differences in the venom protein profile; however, they were not related to the parameters studied (geographic distribution, weight, sex, and captivity time. Moreover, we distinguished two different groups in relation to band densities at 49 and 57 kDa. Specimens with predominant density in the 49kDa band tend to be predominantly females. Weight distribution in this group extended for all the range (150-1500 g with an average weight of 720 g. The other group (57kDa predominant band showed restricted weight range (150-400 g with an average weight of 280 g. Cluster analysis was also performed. The variability observed in the venom profile probably corresponds to genetic variations.

  9. Seasonal, daily activity, and habitat use by three sympatric pit vipers (Serpentes, Viperidae from southern Brazil

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    MARCELO C. ROCHA

    2014-06-01

    Full Text Available Viperid snakes are widely distributed in the South America and the greater distribution range of the family is found at the Crotalinae subfamily. Despite the abundance of this snakes along their geographic distribution, some ecological aspects remain unknown, principally at subtropical areas. In the present study, we evaluated the activity (daily and seasonal and the use of the habitat by Bothrops diporus, B. jararaca andB. jararacussu, in an Atlantic Forest area at southern Brazil. We observed higher incidence of viperid snakes during the months with higher temperatures, while no snakes were found during the months with lower temperatures. The data suggest the minimum temperature as environmental variable with the greatest influence on the seasonal activity of this species. Considering the daily activity, we observed a tendency of snakes to avoid the warmest hours. Bothrops jararacussu tend to avoid open areas, being registered only inside and at the edges of the forest. We compared our results with previous studies realized at tropical areas and we suggest the observed seasonal activity as an evolutive response, despite the influence of the different environmental variables, according to the occurence region.

  10. Seasonal, daily activity, and habitat use by three sympatric pit vipers (Serpentes, Viperidae) from southern Brazil

    OpenAIRE

    ROCHA, MARCELO C.; HARTMANN, PAULO A.; WINCK, GISELE R.; CECHIN, SONIA Z.

    2014-01-01

    Viperid snakes are widely distributed in the South America and the greater distribution range of the family is found at the Crotalinae subfamily. Despite the abundance of this snakes along their geographic distribution, some ecological aspects remain unknown, principally at subtropical areas. In the present study, we evaluated the activity (daily and seasonal) and the use of the habitat by Bothrops diporus, B. jararaca andB. jararacussu, in an Atlantic Forest area at southern Brazil. We obser...

  11. Geographic distribution and apparent decline of Crotalus durissus terrificus (Laurenti 1768; Serpentes, Viperidae) in Uruguay

    OpenAIRE

    Prigioni, Carlos M.; Borteiro, Claudio; Kolenc, Francisco; González, Enrique M.; Colina, Marcelo

    2013-01-01

    Herein, we make a comprehensive account of rattlesnake records in this country obtained from herpetological literature and other bibliographic sources, specimens accessioned in herpetological and non-specialized local collections, and new information gathered during field surveys. Asociación Herpetológica Argentina

  12. Lista y distribución de los ofidios (Reptilia: Serpentes de Santa Fe, Argentina

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    Arzamendia, Vanesa

    2002-05-01

    Full Text Available Se estudió la composición y distribución de las serpientes en la provincia de Santa Fe, Argentina, sobre la base de 1.292 registros obtenidos en muestreos de campo, revisión de las colecciones herpetológicas de Argentina y registros bibliográficos. Se registraron 51 especies y subespecies (43 Colubridae, 3 Viperidae, 2 Boidae, 1 Elapidae, 1 Leptotyphlopidae y 1 Typhlopidae, representando un 39% de los taxones registrados para Argentina. Se realizaron mapas con localidades precisas para determinar la distribución de las serpientes. Una especie y 4 subespecies son registros novedosos para la provincia. Los patrones de distribución son brevemente discutidos en relación con las formaciones fitogeográficas. We studied the composition and distribution of the Santa Fe snakes based on 1,292 examined specimens obtained in field survey, revision of the Argentine herpetological collections and reliable literature records. Maps were built for determinate the distribution of snakes. Fifty one species and subspecies were recorded (43 Colubridae, 3 Viperidae, 2 Boidae, 1 Elapidae, 1 Leptotyphlopidae and 1 Typhlopidae, a 39% of the survey taxa in Argentina. One species and three subspecies were new records in Santa Fe province. The distributional patterns are briefly discussed in relation with phytogeographical subdivisions.

  13. Reproductive biology of the swamp racer Mastigodryas bifossatus (Serpentes: Colubridae in subtropical Brazil

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    Pedro T. Leite

    2009-03-01

    Full Text Available The swamp racer Mastigodryas bifossatus (Raddi, 1820 is a large snake of Colubrinae. It is widely distributed in open areas throughout South America. Dissection of 224 specimens of this species housed in herpetological collections of the southern Brazilian states of Rio Grande do Sul, Santa Catarina and Paraná provided information on its sexual dimorphism, reproductive cycle and fecundity in subtropical Brazil. Adult specimens of M. bifossatus average approximately 1190 mm in snout-vent length and females are larger than males. The reproductive cycle of females is seasonal, with secondary vitellogenesis occurring from July to December. However, examination of male gonads did not reveal signs of reproductive seasonality in this sex. Egg laying was recorded from November to January. The estimated recruitment period extends from February to April. The mean number of individuals per clutch is 15, and there is a positive correlation between female length and clutch size.

  14. New records of Psomophis obtusus (Cope, 1863 (Serpentes: Dipsadidae in Argentina and Uruguay

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    Di Pietro, Diego O.

    2010-12-01

    Full Text Available Herein we report the southernmost locality of the genus Psomophis and a new department record of Psomophis obtusus in Uruguay. We analyzed 23 specimens of P. obtusus deposited at the Herpetological Collections of the Museo Argentino de Ciencias Naturales "Bernardino Rivadavia" (MACN, Centro Nacional de Investigaciones Iológicas (CENAI, housed at MACN, and Museo de La Plata (MLP.

  15. Reproductive biology of the Green Ground Snake Erythrolamprus poecilogyrus sublineatus (Serpentes: Dipsadidae) in Subtropical Brazil.

    Science.gov (United States)

    Quintela, Fernando M; Marques, Wiliam C; Loebmann, Daniel

    2017-01-01

    We investigated reproductive features of the dipsadid snake Erythrolamprus poecilogyrus sublineatus in the southernmost Brazilian coast, a subtropical region characterized by well-marked seasons. Females are significantly smaller than males, have a shorter tail, and reach sexual maturity at later times along their development. In contrast to tropical subspecies, E. p. sublineatus females presented a seasonal pattern, with secondary follicles occurring from late winter to early autumn and egg production restricted to the whole spring and early summer. Males presented seasonal variation in testes volume (increase in autumn and decrease in winter) while no significant seasonal variation was found in ductus deferens width. The number of oviductal eggs varied from two to nine, thus, real fecundity is also inferior than that observed in tropical E. poecilogyrus forms. Considering the thermal requirements for reproduction, it is possible that the colder climatic conditions of the southern Brazilian coast have shaped the seasonal reproductive pattern in E. p. sublineatus. The shorter body size of this subspecies may also represent a conditioning factor of low fecundity.

  16. New record of Boa constrictor occidentalis Philippi, 1873 (Serpentes: Boidae) in San Juan province, Argentina

    OpenAIRE

    Martínez, Tomás; Rodriguez Muñoz, Melina; Galdeano, Ana; Acosta, Juan

    2015-01-01

    We document the first record of Boa constrictor in Valle Fértil department, San Juan province, Argentina. The specimen was collected and deposited in the herpetological collection of the Department of Biology, Universidad Nacional San Juan. This record extends the known distribution for this species in San Juan province by 105 km.

  17. The Evolutionary Implications of Hemipenial Morphology of Rattlesnake Crotalus durissus terrificus (Laurent, 1768 (Serpentes: Viperidae: Crotalinae.

    Directory of Open Access Journals (Sweden)

    Marcovan Porto

    Full Text Available Most amniotes vertebrates have an intromittent organ to deliver semen. The reptile Sphenodon and most birds lost the ancestral penis and developed a cloaca-cloaca mating. Known as hemipenises, the copulatory organ of Squamata shows unique features between the amniotes intromittent organ. They are the only paired intromittent organs across amniotes and are fully inverted and encapsulated in the tail when not in use. The histology and ultrastructure of the hemipenes of Crotalus durissus rattlesnake is described as the evolutionary implications of the main features discussed. The organization of hemipenis of Crotalus durissus terrificus in two concentric corpora cavernosa is similar to other Squamata but differ markedly from the organization of the penis found in crocodilians, testudinata, birds and mammals. Based on the available data, the penis of the ancestral amniotes was made of connective tissue and the incorporation of smooth muscle in the framework of the sinusoids occurred independently in mammals and Crotalus durissus. The propulsor action of the muscle retractor penis basalis was confirmed and therefore the named should be changed to musculus hemipenis propulsor.The retractor penis magnus found in Squamata has no homology to the retractor penis of mammals, although both are responsible for the retraction of the copulatory organ.

  18. From Serpent to CEO: Improving First-Term Security Forces Airman Performance Through Neuroscience Education

    Science.gov (United States)

    2017-06-09

    support procedures and decision - making processes. Creating awareness that limitations are present creates a natural motivation to want to reduce...law enforcement decision - making ? What cultural norms within Security Forces should be challenged to improve responses of young adults faced with...enforcement and combat decision - making processes is available. However, it is not uncommon for laboratory discoveries to enter clinical practice, not to

  19. The Serpent in Our Garden: Al-Qa’Ida and The Long War

    Science.gov (United States)

    2008-03-25

    directed organization into a worldwide franchiser of terrorist groups and cells.68 They have also selected a comparable lean business model for...Savagery Phase. After defeating Western forces, the mujahidin will establish internal security, ensure the people have the necessary food and supplies...impact upon Americans, as well as a corresponding economic ripple. Terror attacks on our subways , railways, and the airline industry will certainly

  20. Analysis of deterioration of rocky material which conform the sculptured serpents of the Tenayuca pyramid

    International Nuclear Information System (INIS)

    Mendoza A, D.; Martinez C, G.; Rodriguez L, V.

    2004-01-01

    This work presents the results about the characterization of rocky materials samples proceeding from heads of snakes that adorn the pyramid of Tenayuca, Mexico. Analysis of these samples, that show deterioration presence was performance through Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD). Several morphological structures such as granular, tubular, acicular growths and fibers were observed, some of they could be associate to salt migration. It was possible to identify different crystalline phases associated with albite (NaAlSi 3 O 8 ), anorthite [(Ca,Na)(Si,Al) 4 O 8 ], ferroactinolite [(Ca,Na,K) 2 Fe 5 Si 8 O 22 (OH) 2 ], gypsum (CaSO 4 2H 2 O), quartz (SiO 2 ) and thenardite (Na 2 SO 4 ). (Author) 10 refs., 2 tabs., 12 figs

  1. Field observations of mating behavior in the neck-banded snake Scaphiodontophis annulatus (Serpentes: Colubridae

    Directory of Open Access Journals (Sweden)

    Mahmood Sasa

    2006-06-01

    Full Text Available We observed the mating behavior of the neck-banded snake Scaphiodontophis annulatus (a common species of colubrid in the South Pacific of Costa Rica in the pre-montane wet forest of Las Cruces Biological Station (San Vito de Java, Costa Rica. Three S. annulatus were observed during courtship between 10-12 AM in a patch of primary forest. The two males were observed to interact with the female, but not signs of male-male agonistic interactions were observed. Their behavior includes grabbing and holding the female, copula, and biting during the copula. Rev. Biol. Trop. 54(2: 647-650. Epub 2006 Jun 01.El comportamiento de apareamiento es descrito para la serpiente Scaphiodontophis annulatus, una especie de colúbrido común en el Pacífico sur de Costa Rica. El comportamiento incluye capturar y sujetar a la hembra, mordiscos durante la cópula y coito. Dos machos fueron observados al interactuar con una sola hembra, pero no se detectó señales de interacciones antagónicas macho-macho.

  2. Renewable maritime energies. Facing the 2020 target, will the Sea Serpent emerge at last?

    International Nuclear Information System (INIS)

    2009-01-01

    Dealing with the production of renewable energy in maritime environments, a series of articles comments the activities of various French organisations in this area: research organisations like Ifremer or the Ecole Centrale de Nantes (an engineering school), public organisations like the ADEME, private or public companies like Total, EDF, GDF, Enertrag in the search or in the development of technologies aimed at the production of energy by different methods: wind energy (with offshore wind farm projects), tidal energy, maritime biomass energy, osmotic energy, sea thermal energy (notably in Reunion Island), tidal energy or the energy which could be generated from waves or from the swell. As the first article recalls it, the objective is to reach the objective of 23% of renewable energies in the French consumption by 2020. Some assessments of the French potential production in these different domains are given, as well as prospective data about the capacities of European countries in the large scale development of offshore wind farms as recommended by the European Commission. These activities and some difficulties (for the first French offshore wind turbine project) are also discussed in interviews with engineers, researchers or company managers

  3. Scent gland constituents of the Middle American burrowing python, Loxocemus bicolor (Serpentes: Loxocemidae).

    Science.gov (United States)

    Schulze, Thies; Weldon, Paul J; Schulz, Stefan

    2017-07-14

    Analysis by gas chromatography/mass spectrometry of the scent gland secretions of male and female Middle American burrowing pythons (Loxocemus bicolor) revealed the presence of over 300 components including cholesterol, fatty acids, glyceryl monoalkyl ethers, and alcohols. The fatty acids, over 100 of which were identified, constitute most of the compounds in the secretions and show the greatest structural diversity. They include saturated and unsaturated, unbranched and mono-, di-, and trimethyl-branched compounds ranging in carbon-chain length from 13 to 24. The glyceryl monoethers possess saturated or unsaturated, straight or methyl-branched alkyl chains ranging in carbon-chain length from 13 to 24. Alcohols, which have not previously been reported from the scent glands, possess straight, chiefly saturated carbon chains ranging in length from 13 to 24. Sex or individual differences in secretion composition were not observed. Compounds in the scent gland secretions of L. bicolor may deter offending arthropods, such as ants.

  4. The rhinoceros among Serpents: Comparative anatomy and experimental biophysics of Calabar burrowing python (Calabaria reinhardtii) skin.

    Science.gov (United States)

    Han, Dawei; Young, Bruce A

    2018-01-01

    The Calabar burrowing python (Calabaria reinhardtii) has a unique combination of marked thickness of the integumentary layers, a highly organized lamellate arrangement of the dermal collagen bundles, and a reduction in the size of the interscale hinge region of the integument. Biomechanical testing demonstrates that the skin of C. reinhardtii is more resistant to penetration than the skin of other snakes. The laminar arrangement of the collagen bundles provides for penetrative resistance, even while maintaining the flexibility characteristic of snake skin. Considering the life history of this species, it is hypothesized that the specialized integument of C. reinhardtii is a passive defensive mechanism against penetrative bites from maternal rodents and predators. © 2017 Wiley Periodicals, Inc.

  5. Complete mitochondrial genome sequence from an endangered Indian snake, Python molurus molurus (Serpentes, Pythonidae).

    Science.gov (United States)

    Dubey, Bhawna; Meganathan, P R; Haque, Ikramul

    2012-07-01

    This paper reports the complete mitochondrial genome sequence of an endangered Indian snake, Python molurus molurus (Indian Rock Python). A typical snake mitochondrial (mt) genome of 17258 bp length comprising of 37 genes including the 13 protein coding genes, 22 tRNA genes, and 2 ribosomal RNA genes along with duplicate control regions is described herein. The P. molurus molurus mt. genome is relatively similar to other snake mt. genomes with respect to gene arrangement, composition, tRNA structures and skews of AT/GC bases. The nucleotide composition of the genome shows that there are more A-C % than T-G% on the positive strand as revealed by positive AT and CG skews. Comparison of individual protein coding genes, with other snake genomes suggests that ATP8 and NADH3 genes have high divergence rates. Codon usage analysis reveals a preference of NNC codons over NNG codons in the mt. genome of P. molurus. Also, the synonymous and non-synonymous substitution rates (ka/ks) suggest that most of the protein coding genes are under purifying selection pressure. The phylogenetic analyses involving the concatenated 13 protein coding genes of P. molurus molurus conformed to the previously established snake phylogeny.

  6. Reptilia, Serpentes, Dipsadidae, Gomesophis brasiliensis (Gomes, 1918: Distribution extension in state of Santa Catarina, Brazil.

    Directory of Open Access Journals (Sweden)

    Fortes, V. B.

    2010-01-01

    Full Text Available The Brazilian burrowing snake, Gomesophis brasiliensis, occurs in aquatic habitats such as swamps, from MinasGerais and Distrito Federal until Rio Grande do Sul. In spite of this wide distribution, the species’ geographic range stillremains unclear. This note reports the occurrence of G. brasiliensis in the municipality of Vargem Bonita, state of SantaCatarina, south Brazil, extending the species’ range ca. 80 km to the west in this state.

  7. Biologia reprodutiva de Dipsas neivai Amaral e D. catesbyi (Sentzen (Serpentes, Colubridae no sudeste da Bahia, Brasil Reproductive biology in Dipsas neivai and D. catesbyi (Serpentes, Colubridae in southeastern Bahia, Brasil

    Directory of Open Access Journals (Sweden)

    Fátima Q. Alves

    2005-09-01

    Full Text Available A biologia reprodutiva de Dipsas neivai Amaral, 1923 e Dipsas catesbyi (Sentezen, 1796 foi estudada através da dissecção de 261 espécimes de D. neivai e 222 de D. catesbyi. Em D. neivai o macho amadurece com menor tamanho do que a fêmea, ocorrendo o oposto em D. catesbyi. Em ambas as espécies a fêmea atinge maior tamanho corporal que o macho. O tamanho da ninhada variou de um a oito ovos em D. neivai e de um a seis em D. catesbyi, não estando correlacionado com o tamanho da fêmea na última. O ciclo reprodutivo em ambos machos e fêmeas é contínuo, com vitelogênese e espermatogênese ocorrendo ao longo do ano todo. Em Dipsas neivai, a cópula nas fêmeas é dissociado da vitelogênese. D. neivai e D. catesbyi são sintópicas, e reproduzem no mesmo período do ano, o que possivelmente está relacionado à disponibilidade contínua de presas e à pouca variação climática no sudeste da Bahia.The reproductive biology of Dipsas neivai Amaral, 1923 and Dipsas catesbyi (Sentzen, 1796, was studied by dissecting 261 specimens of D. neivai and 222 of D. catesbyi. In D. neivai males mature at smaller body size than females, and in D. catesbyi the opposite was observed. The females were larger than males in both species. The clutch size ranged from one to eight in D. neivai, and one to six in D. catesbyi, but it is not correlated with female length in the last one. Reproductive cycles in both males and females are aseasonal, with vitelogensis and spermatogenesis occurring throughout the year. The couple in females of D. neivai is dissociated from the vitellogenesis. D. neivai and D. catesbyi are syntopic and reproduce in the same time of the year, which is possibly related to the continuous availability of prey and little climate variation in southern Bahia.

  8. Biología reproductiva de la serpiente semiacuática Liophis semiaureus (Serpentes, Colubridae en el nordeste de Argentina Reproductive biology of the semi-aquatic snake Liophis semiaureus (Serpentes, Colubridae in the north-east of Argentina

    Directory of Open Access Journals (Sweden)

    SOLEDAD M LÓPEZ

    2009-06-01

    Full Text Available Las serpientes tienen una notable flexibilidad y diversidad en sus tácticas reproductivas, a pesar de ello, los estudios acerca de la biología reproductiva de especies sudamericanas en zonas subtropicales-templadas son escasos. Se analizó la biología reproductiva de Liophis semiaureus en el nordeste de Argentina, incluyendo la madurez y dimorfismo sexual, fecundidad y ciclo reproductivo. Las hembras maduras fueron significativamente más largas, presentaron mayor peso corporal y alcanzaron la madurez sexual a una longitud mayor que los machos. Los machos tuvieron colas más largas que las hembras. El ciclo reproductivo fue estacional con mayor actividad en los períodos templados del año aunque previos a la época de inundaciones. Liophis semiaureus invirtió más energía en la reproducción que en el crecimiento, lo que posibilita que comiencen a reproducirse con tamaños más pequeños con respecto a otras poblaciones, sin retrasar su reproducción hasta alcanzar mayores tamaños. Esta puede ser una estrategia ventajosa en climas estacionales. Las características reproductivas y de dimorfismo sexual en L. semiaureus se encontrarían influenciadas por aspectos filogenéticos, geográficos y ecológicos, lo que determina que la especie responda de manera general al patrón reproductivo del grupo taxonómico pero con particularidades propias determinadas por los factores geográficos y los requerimientos ecológicos.Snakes in subtropical warm zones have a wide flexibility and diversity in your reproductive tactics. In spite of it, the studies in South America about that are scanty yet. We analyzed sexual dimorphism, sexual maturity, fecundity and reproductive cycle of a semi-aquatic snake, Liophis semiaureus, in north-east of Argentina. Females were significantly longer and heavier than the males. Females reach sexual maturity with longer snout-vent length than the males. Males had longer tails than the females. The reproductive cycle was seasonal. The individuals were more active on the first warm stations of the year and before the floods. Liophis semiaureus spent more energy in reproduction than growth, so they began to reproduce with smaller bodies than others population, this pattern of reproduction could be a profitable strategy in an environment of seasonal climate. The reproduction and sexual dimorphism in L. semiaureus would be influenced by aspects phylogenetic, geographical and ecological. The above aspects were similar to the taxonimic group but with their own characteristics due to geographical factors and to ecological requirements.

  9. Variação anual do sistema reprodutor de fêmeas de Bothrops jararaca (Serpentes, Viperidae Annual variation of the reproductive system in females of Bothrops jararaca (Serpentes, Viperidae

    Directory of Open Access Journals (Sweden)

    Thélia R. F. Janeiro-Cinquini

    2004-09-01

    Full Text Available The morphological changes of the ovary and oviduct of 238 tropical snakes Bothrops jararaca (Wied, 1824 were determined. The ovarian mass presented a remarkable decrease in October, after ovulation, staying in low levels from November to March, during the gestational period. From April to September, it increased because of the ovarian follicles maturation. A gradual increase in oviduct weight was observed from October to March due to stages of embryonic development. A significant difference was observed between right and left ovary weight, and oviduct length, independently of the months considered.

  10. Envenomation by neotropical Opisthoglyphous colubrid Thamnodynastes cf. pallidus Linné, 1758 (Serpentes:Colubridae in Venezuela Envenenamiento por la colubrida opistoglifa Thamnodynastes cf. pallidus Linné, 1758 (Serpentes:Colubridae en Venezuela

    Directory of Open Access Journals (Sweden)

    Fresnel Diaz

    2004-10-01

    Full Text Available This is a case report of a "non-venomous" snake bite in a herpetologist observed at the Sciences Faculty of the Universidad de los Andes (Mérida, Venezuela. The patient was bitten on the middle finger of the left hand, and shows signs of pronounced local manifestations of envenomation such as bleeding from the tooth imprint, swelling and warmth. He was treated with local care, analgesics, and steroids. He was dismissed from the hospital and observed at home during five days with marked improvement of envenomation. The snake was brought to the medical consult and identified as a Thamnodynastes cf. pallidus specimen. This report represents the first T. pallidus accident described in a human.Se reporta un caso de una mordedura de serpiente "no venenosa", en un herpetólogo observado en la Facultad de Ciencias de la Universidad de los Andes (Mérida, Venezuela. El paciente fue mordido en el dedo medio de la mano izquierda, mostrando pronunciados signos locales de sangramiento por la impronta ocasionada por los dientes de la serpiente, edema y calor local. El paciente fue tratado con cuidados locales, analgésicos y esteroides. Fue dado de alta del hospital y observado en el hogar durante 5 días, con marcada mejoría del envenenamiento. La serpiente fue traída a la consulta médica e identificada como un espécimen de Thamnodynastes cf. pallidus. Este es el primer caso humano descrito, ocasionado por un T. pallidus.

  11. Notas sobre la ocurrencia de Pelamis platurus (Reptilia: Serpentes: Hydrophiidae en el Pacífico Colombiano

    Directory of Open Access Journals (Sweden)

    Álvarez León Ricardo

    1998-11-01

    Full Text Available The presence of the Pelamis platurus (Linnaeus in the Colombian Pacific coast, is confirmed based on 35 reports (18 published and 17 unpublished, and 36 individual records in national colections. The pelagic sea snake is commonly found in large yellow and black aggregations along slick and drift lines in the areas of Isla Gorgona-Cabo Marzo. Additionally, the brown pelican Pelecanus occidentalis is recorded for the first time as a predator of Pelamis platurus in the American Pacific.Se discute la presencia de Pelamis platurus (Linnaeus en el Pacífico colombiano con base en 35 registros (18 publicados y 17 inéditos, y 36 ejemplares en colecciones nacionales. La serpiente marina es común y abundante entre Isla Gorgona y Cabo Marzo, donde forma densas agregaciones amarillas y negras, a lo largo de las costas. Adicionalmente se registra el pelícano marrón Pelecanus occidentalis por primera vez como un depredador de Pelamis platurus en el Pacífico americano.

  12. The unexpected discovery of blind snakes (Serpentes: Typhlopidae) in Micronesia: two new species of Ramphotyphlops from the Caroline Islands

    Science.gov (United States)

    Wynn, Addison H.; Reynolds, Robert P.; Buden, Donald W.; Falanruw, Marjorie; Lynch, Brian

    2012-01-01

    Two new blind snakes in the genus Ramphotyphlops are described from Ulithi (R. hatmaliyeb sp. nov.) and Ant Atoll (R. adocetus sp. nov.) in the Caroline Islands, the first blind snake species known from Micronesia east of Palau (excluding Ramphotyphlops braminus). Both species are unusual in being known only from small, low-lying atolls. They can be distinguished from other Ramphotyphlops by the combination of 22 scale rows over the length of the body; a wedge-shaped snout, without a keratinized keel; and a broad, pyriform (R. adocetus) or ovate (R. hatmaliyeb) rostral scale.

  13. Case 3693 Cryptodacus Hendel, 1914 (Insecta: Diptera: Tephritidae): Proposed suppression of Cryptodacus Gundlach, 1862 (Reptilia, Serpentes, Colubridae)

    Science.gov (United States)

    Norrbom, Allen L.; McDiarmid, Roy W.; Chen, Xiao-Lin; David, King J.; De Meyer, Marc; Freidberg, Amnon; Han, Ho-Yeon; Steck, Gary J.; Thompson, F. Christian; White, Ian M.; Zucchi, Roberto A.

    2015-01-01

    The purpose of this application, under Article 23.9.3, is to conserve current usage of the well-established genus-group name Cryptodacus Hendel, 1914 for a genus of Neotropical fruit flies by suppression of the earlier, unused name Crypto- dacus Gundlach, 1862, currently a junior synonym of Arrhyton Günther, 1858, a genus of snakes, under the plenary power of the Commission, in the interest of nomenclatural stability. Cryptodacus Gundlach has not been used as a valid name since 1883, whereas Cryptodacus Hendel has been used in a significant body of literature relating to fruit fly systematics, morphology and phylogeny and is the currently used name in various name and molecular databases. 

  14. Características biológicas e inmunológicas del veneno de Bothrops cotiara (Serpentes: Viperidae)

    OpenAIRE

    Adolfo Rafael de Roodt; Judith Estévez; Jorge Adrián Dolab; Marcelo Víctor Manzanelli; Nicolás Piñeiro; Jorge Francisco Paniagua; Alejandro Urs Vogt

    2006-01-01

    Bothrops cotiara es una serpiente que se encuentra en la provincia de Misiones (Argentina), el Sur de Brasil y Paraguay. La información sobre las características clínicas de los accidentes por esta serpiente es muy escasa y existen pocos datos sobre su veneno y la capacidad neutralizante de las actividades tóxicas del mismo por antivenenos terapéuticos. En este trabajo se estudiaron características bioquímicas, actividades tóxicas y la reactividad inmunoquímica del veneno de B. cotiara. Seis ...

  15. Morphological, morphometric, and molecular characterization of Hepatozoon spp. (Apicomplexa, Hepatozoidae) from naturally infected Caudisona durissa terrifica (Serpentes, Viperidae).

    Science.gov (United States)

    Moço, Tatiana Cristina; da Silva, Reinaldo José; Madeira, Newton Goulart; Dos Santos Paduan, Karina; Rubini, Adriano Stefani; Leal, Denise Dutra Menezes; O'Dwyer, Lucia Helena

    2012-04-01

    Hepatozoon spp. are the most frequent intracellular protozoa in snakes. Considering the variety of parasites infecting specimens of Caudisona durissa terrifica and the divergent data in literature where only two species, Hepatozoon romani and Hepatozoon capsulata, are described, the aim of this study was to morphologically, morphometrically, and molecularly characterize Hepatozoon spp. from some naturally infected specimens of C. durissa terrifica, and observe changes caused by these protozoa in parasitized erythrocytes. Four snakes were examined. Two of them had two morphological distinct gamonts, while the other two had only one type of gamont. The six distinct gamonts were provisionally named gamonts A, B, C, D, E, and F. Statistical analysis, however, confirmed the existence of only four parasite populations, those which were capable of inducing significant alterations in determined red blood cells variables. Attempts to infect Aedes aegypti and Culex quinquefasciatus mosquitoes were done for each snake specimen. Some mosquitoes became infected and oocysts were recovered and measured. The detection of Hepatozoon DNA was obtained with success but the molecular characterization was unable to differentiate species of the samples, with respect to the fragment studied.

  16. Sea snakes in Australian waters (Serpentes: subfamilies Hydrophiinae and Laticaudinae)—a review with an updated identification key

    DEFF Research Database (Denmark)

    Redsted Rasmussen, Arne; Sanders, Kate Laura; Guinea, Michael L

    2014-01-01

    Sea snakes (Elapidae, subfamilies Hydrophiinae and Laticaudinae) reach high species richness in the South China Sea and in the Australian region; however, most countries in the two regions still lack up-to-date checklists and identification tools for these snakes. We present an updated reviewed...... checklist and a new complete identification key to sea snakes in Australian waters. The identification key includes 29 species documented and 4 possibly occurring taxa and is based mostly on easy-to-use external characters. We find no evidence for breeding populations of Laticauda in Australian waters...

  17. "ära vaata aknast välja..." : [luuletused] / =[Mesikepp, Indrek] François Serpent

    Index Scriptorium Estoniae

    Serpent, François, pseud., 1971-

    2002-01-01

    Sisu: "ära vaata aknast välja..." ; "toidukaupade osakond..." ; imelikke inimesi mõeldakse välja ; "öösel kolmveerand neli..." ; "ma ei karda liblikaid..." ; "pohmell me yhises kehas..." ; "mida ma teeksin Sinuta Ave..." ; "need ei olnudki mõõgad..."

  18. ["Lingue di seripi", "serpents' tongues" and "glossopetrae". Highlights from the history of popular "cult" medicine in early modern times].

    Science.gov (United States)

    Freller, T

    1997-01-01

    In the 16th, 17th and 18th century "Glossopetrae", popularly known as "Lingue di Serpi", found on the Mediterranean island of Malta, were extensively used for medical purposes as antidotes. These fossil teeth, including specimens of the "Carcharodon Megalodon" (an extinct variant of the great white shark), were ground to powder or used as amulet pendants and "credence" and exported to pharmacies and shops in various cities of Europe. In antiquity, authors like Plinius or Solinus, excluding any religious connotations, had regarded "Glossopetrae" as objects "fallen from heaven on dark moonless nights". However, from the beginning of the 16th century the miraculous antidotic power of the specimens found at Malta was very strongly connected with the Pauline cult there. This cult owed ist origin to the excerpt of the shipwreck of the Apostle of the Gentiles on this island, as recorded in the New Testament. As in so many cases found in medieval and early modern medicine and pharmacy, the renown, collection, distribution and use of the antidote "Glossopetrae" or "Lingue di Serpi" was never limited to its real chemical and pharmaceutical properties. In the period of enlightenment and secular thinking mythic medicine as "Glossopetrae" had lost ist "magical" power. Consequently, with beginning of the late 18th century also the Maltese "Glossopetrae" featured in literature merely as exotic objects of curiosity or symbols of an age bound to medical superstition.

  19. Annotated checklist of the recent and extinct pythons (Serpentes, Pythonidae), with notes on nomenclature, taxonomy, and distribution

    Science.gov (United States)

    Schleip, Wulf D.; O’Shea, Mark

    2010-01-01

    Abstract McDiarmid et al. (1999) published the first part of their planned taxonomic catalog of the snakes of the world. Since then, several new python taxa have been described in both the scientific literature and non-peer-reviewed publications. This checklist evaluates the nomenclatural status of the names and discusses the taxonomic status of the new taxa, and aims to continue the work of McDiarmid et al. (1999) for the family Pythonidae, covering the period 1999 to 2010. Numerous new taxa are listed, and where appropriate recent synonymies are included and annotations are made. A checklist and a taxonomic identification key of valid taxa are provided. PMID:21594030

  20. Genetic differentiation among species of the genus Thermophis Malnate (Serpentes, Colubridae) and comments on T. shangrila.

    Science.gov (United States)

    Hofmann, Sylvia; Tillack, Frank; Miehe, Georg

    2015-10-07

    The genus Thermophis includes the two species, T. baileyi and T. zhaoermii, which differ morphologically, geographically and molecularly. Recently, a third Thermophis species was described from Shangri-La, northern Yunnan Province, China, and named T. shangrila. The new species was based on morphological and genetic data derived from three specimens. However, the morphological features used to delimit this species seem vague, because they may fall within the range of intraspecific variation of T. zhaoermii. Furthermore, the reported genetic differences in nuclear data are questionable. They likely resulted from a misinterpretation probably due to alignment/analytical flaws or sample/sequence mix-up. Here, we used partial sequences of three mitochondrial (CO1, ND4, cytb) genes and one nuclear (c-mos) gene to analyse the genetic variation between and within species of Thermophis. We inferred the phylogeny using Bayesian Inference and Maximum Likelihood approaches and present additional morphological data that contribute to the knowledge on intraspecific variation in the genus. Our results indicate lacking robustness in the distinguishing morphological features and in the genetic differentiation of T. shangrila and highlight the need for more detailed morphological and molecular studies from a substantially larger sample.

  1. A new species of Hepatozoon (Apicomplexa: Adeleorina) from Python regius (Serpentes: Pythonidae) and its experimental transmission by a mosquito vector

    Czech Academy of Sciences Publication Activity Database

    Sloboda, M.; Kamler, M.; Bulantová, J.; Votýpka, Jan; Modrý, David

    2007-01-01

    Roč. 93, č. 5 (2007), s. 1189-1198 ISSN 0022-3395 R&D Projects: GA MŠk(CZ) LC06009; GA ČR GD524/03/H133 Grant - others:GA ČR(CZ) GP524/03/D104 Institutional research plan: CEZ:AV0Z60220518 Keywords : Hepatozoon * Python * Culex * transmission * SSU Subject RIV: EG - Zoology Impact factor: 1.129, year: 2007

  2. Eimeria jayakaris sp. n. (Apicomplexa:Eimeriidae) from the snake, Eryx jayakari (Serpentes: Boidae) in Saudi Arabia

    International Nuclear Information System (INIS)

    Alyousif, Mohamed S; AlShawa, Yaser R

    2007-01-01

    A new coccidian parasite of the genus Eimeria is described from the gall bladder of the boid snake, Eryx jayakari collected from Althumamah, central region, Saudi Arabia. Oocysts of Eimeria jayakaris sp. n. are ellipsoid, measuring 31x19.5 (28.7-33.5 x 18.5-20.8) micron meter, with a smooth greenish-yellow bilayered oocyst wall of 1.1 (0.9-1.2) micron meter. Micropyle, oocyst residuum and polar granule are absent. Sporocysts are ellipsoidal, measuring 12 x 9.3 (10.7-12.8x8-10) micron meter. Sporocyst residuum is present as a granulated compact mass. Sporocysts lack a Stieda body. Sporozoites are banana-shaped, laying head to tail in the sporocysts, each with one spherical refractile globule. (author)

  3. Molecular phylogeny of Atractus (Serpentes, Dipsadidae), with emphasis on Ecuadorian species and the description of three new taxa

    Science.gov (United States)

    Arteaga, Alejandro; Mebert, Konrad; Valencia, Jorge H.; Cisneros-Heredia, Diego F.; Peñafiel, Nicolás; Reyes-Puig, Carolina; Vieira-Fernandes, José L.; Guayasamin, Juan M.

    2017-01-01

    Abstract We present a molecular phylogeny of snake genus Atractus, with an improved taxon sampling that includes 30 of the 140 species currently recognized. The phylogenetic tree supports the existence of at least three new species in the Pacific lowlands and adjacent Andean slopes of the Ecuadorian Andes, which we describe here. A unique combination of molecular, meristic and color pattern characters support the validity of the new species. With the newly acquired data, we propose and define the Atractus iridescens species group, as well as redefine the Atractus roulei species group. The species Atractus iridescens is reported for the first time in Ecuador, whereas Atractus bocourti and Atractus medusa are removed from the herpetofauna of this country. We provide the first photographic vouchers of live specimens for Atractus multicinctus, Atractus paucidens and Atractus touzeti, along with photographs of 19 other Ecuadorian Atractus species. The current status of Atractus occidentalis and Atractus paucidens is maintained based on the discovery of new material referable to these species. With these changes, the species number reported in Ecuador increases to 27, a number that is likely to increase as material not examined in this work becomes available and included in systematic studies. PMID:28769604

  4. Tyzzeria boae n. sp., (Apicomplexa: Eimeriidae, a New Coccidium from the Kidney of the snake Boa constrictor constrictor (Serpentes: Boidae

    Directory of Open Access Journals (Sweden)

    Ralph Lainson

    1994-12-01

    Full Text Available A new species of Tyzzeria is described from the kidney of the snake Boa constrictor constrictor Linnaeus, from the State of Pará, north Brazil. Oocysts from the coacal contents matured in eight days, at approximately 24°C. They measured 19.0 x 18.0 (15.0 x 15.0 - 22.5 x 21.5 µm, shape-index (length/width 1.0 (1.0 - 1.1. The oocyst wall is of an extremely delicate single, colourless layer, with no micropyle. Division of the oocyst contents into the 8 naked sporozoites leaves a bulky, spherical oocyst residuum averaging 15.5 x 14.8 (13.5 x 13.5 - 18.5 x 17.5 µm; the sporozoites measure an average of 11.0 x 1.8 (8.5 x 1.25 - 12.5 x 2.0 µm, and possess both anterior and posterior refractile bodies. Tyzzeria boae n.sp. is unique among the recorded species of the genus by virtue of its development in the epithelial cells of the distal convoluted tubules and collecting tubules of the kidney: stages in the merogony and gametogony of the parasite are described and figured.

  5. Report of Nagarjunasagar Racer Coluber bholanathi Sharma, 1976 (Squamata: Serpentes: Colubridae from the Gingee Hills, Tamil Nadu, India

    Directory of Open Access Journals (Sweden)

    U. Smart

    2014-04-01

    Full Text Available Since its initial description in 1976 from Nagarjuna Hills, Andhra Pradesh, the endemic Nagarjaunasagar Racer Coluber bholanathi has remained elusive for over 30 years, only to be re-discovered in 2012. Here, we report this rare snake from the Gingee Hills, Tamil Nadu, extending the known geographic range by 495km south of the type locality and 194km south-east of Thally, Tamil Nadu, its previously southernmost locality. We also provide comparative information consisting of locality data, morphology and color pattern for both the Nagarjunasagar Racer and a similar-looking species The Slender Racer.

  6. The serpent and the Madonna: Senses, practices and soundscapes in a vodou site: Saut d’Eau, Haiti

    Directory of Open Access Journals (Sweden)

    Francesco Ronzon

    2017-12-01

    Full Text Available L’articolo analizza la relazione tra sensi, pratiche e paesaggi sonori in relazione a Sodo, sede di un pellegrinaggio vodou su scala nazionale ad Haiti. Partendo dagli studi sui soundscapes (Schafer 1977 come punto di vista teorico per analizzare l’interazione tra suono e persone in un luogo specifico, l’articolo mostra l’interazione tra suoni ambientali, musica registrata e performance dal vivo. In particolare, questa ricerca vuole investigare il micro livello dell’ascolto situato, ovvero i modi con i quali gli attori sociali indirizzano la loro attenzione verso i suoni dell’ambiente in relazione alle loro pratiche sociali, culturali e religiose.

  7. Les morsures de serpent en milieux pédiatriques à l'hôpital de l ...

    African Journals Online (AJOL)

    FAV-Afrique) actif sur les espèces Bitis, Echis, Naja et Dendroaspis de Sanofi Pasteur couplé au besoin d'un traitement symptomatique. Résultats: Un total de 56 dossiers de patients (sex-ratio 1,6; âge moyen = 9,36 ± 3,66 ans) ont été colligés ...

  8. The unexpected discovery of blind snakes (Serpentes: Typhlopidae) in Micronesia: two new species of Ramphotyphlops from the Caroline Islands

    Science.gov (United States)

    Addison H. Wynn; Robert P. Reynolds; Donald W. Buden; Marjorie Falanruw; Brian. Lunch

    2012-01-01

    Two new blind snakes in the genus Ramphotyphlops are described from Ulithi (R. hatmaliyeb sp. nov.) and Ant Atoll (R.adocetus sp. nov.) in the Caroline Islands, the first blind snake species known from Micronesia east of Palau (excludingRamphotyphlops braminus). Both species are unusual in...

  9. Data on the reproduction of a Caucasian Viper, Vipera kaznakovi Nikolsky, 1909 (Serpentes: Viperidae from Hopa (Northeastern Anatolia, Turkey

    Directory of Open Access Journals (Sweden)

    Bayram Göçmen

    2013-12-01

    Full Text Available In the current study we report an observation of a Caucasian Viper, Vipera kaznakovi from Hopa (Artvin, Turkey giving birth. During our field studies, we captured a female Vipera kaznakovi on July 21, 2012 from Esenkıyı village, Hopa (Artvin, Turkey, it was brought to the laboratory and kept in a terrarium for a period until May 28, 2013. The female (SVL= 483 mm, total length, TL = 541 mm gave birth to eight young (mean SVL= 146 mm, mean TL= 161.4 mm, range= 155 – 172 mm; mean weight, W= 3.11 g, range= 2.6 – 3.4 g on August 11, 2012. In six and a half months, the juvenile snakes had reached 163 mm SVL, 187 mm TL and 5.1g W and increased their size by approximately 15%.

  10. Body size, reproductive biology and abundance of the rare pseudoboini snakes genera Clelia and Boiruna (Serpentes, Colubridae) in Brazil

    OpenAIRE

    Lígia Pizzatto

    2005-01-01

    Pseudoboini snakes of the genera Clelia and Boiruna are apparently rare in nature and certainly rare in collections. This work presents data on body size, reproduction and abundance of five Brazilian species of these genera, in the largest collection of snakes in Latin America, the Instituto Butantan. Despite scarcity of data, follicular cycle seems to be continuous in most species, except Clelia rustica, which occurs in highlands. Females are largerthan males in all species, and fecundity is...

  11. Body size, reproductive biology and abundance of the rare pseudoboini snakes genera Clelia and Boiruna (Serpentes, Colubridae in Brazil

    Directory of Open Access Journals (Sweden)

    Lígia Pizzatto

    2005-12-01

    Full Text Available Pseudoboini snakes of the genera Clelia and Boiruna are apparently rare in nature and certainly rare in collections. This work presents data on body size, reproduction and abundance of five Brazilian species of these genera, in the largest collection of snakes in Latin America, the Instituto Butantan. Despite scarcity of data, follicular cycle seems to be continuous in most species, except Clelia rustica, which occurs in highlands. Females are largerthan males in all species, and fecundity is low when compared to other pseudoboini. Abundance is very low for all species even considering 100 years of collecting, and it is decreasing in recent decades when compared to other snakes (Bothrops jararaca, Oxyrhopus guibei, O. clathratus, Philodryas patagoniensis, Sibynomorphus mikanii, and Spilotes pullatus. The studied species present at least five traits of commonly threatened species and require more attention in researches and conservation policies.

  12. High helmintic infection of the European grass snake, Natrix natrix and the dice snake, Natrix tessellate (Serpentes: Colubridae from Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Yossefi

    2014-02-01

    Full Text Available Objective: To determine the helminth parasites of Natrix natrix Linnaeus, 1758 (N. natrix and Natrix tessellata Laurenti, 1768 (N. tessellate in north of Iran. Methods: Eighteen snakes including nine N. natrix and nine N. tessellata from Mazandaran Province, north of Iran were collected and examined during March 2011 to October 2011 for helminth parasites. The collected specimens were fixed and preserved in 70% ethanol. Results: All of the examined snakes (100% were infected with parasitic helminth. The list of extracted helminths both in N. natrix and N. tessellata includes one Nematode: Rhabdias fuscovenosa (larva, one Digenea: Telorchis assula and one Cestoda: Ophiotaenia europaea. The infection rate of Ophiotaenia europaea, Telorchis assula and Rhabdias fuscovenosa (larva from collected snakes were 100%, 83.3% and 61.1%, respectively. Moreover, in the current investigation the morphological characteristics of the collected helminths were described elaborately. Conclusions: This is the first survey on helminth parasites from N. tessellata in Iran and the helminthes are reported for the first time from this host in Iran.

  13. Novos gêneros e espécies de ácaros (Mesostigmata, Ixodorhynchidae ectoparasitas de serpentes

    Directory of Open Access Journals (Sweden)

    Nélida M. Lizaso

    1982-01-01

    Full Text Available Ectoparasitic mites on Brazilian non-poisonous snakes, collected from March 1976 to December 1979, are herein reported. A systematic study of the Ixodorhynchidae, which include exclusively parasites of snakes is given, including all immature forms. Two new genera are described: Ophiogongylus gen.n. with two species: Ophiogongylus rotundus sp.n. and Ophiogongylus breviscutum sp.n. and Chironobius gen.n. with two species: Chironobius alvus sp.n. and Chironobius nordestinus sp.n. Ixobioides brachispinosus sp.n. and the male of Ixobioides fonsecae (Fain are also described. Immature forms, hosts relations and geographical distribution are given for the species.

  14. Postovipositional development of the sand snake Psammophis sibilans (Serpentes:Lamprophiidae) in comparison with other snake species

    Czech Academy of Sciences Publication Activity Database

    Khannoon, E. R.; Zahradníček, Oldřich

    2017-01-01

    Roč. 98, č. 2 (2017), s. 144-153 ISSN 0001-7272 R&D Projects: GA ČR GB14-37368G Institutional support: RVO:68378041 Keywords : embryonic development * Psammophis * snake Subject RIV: EA - Cell Biology OBOR OECD: Developmental biology Impact factor: 1.211, year: 2016

  15. Three new endemic species of Epictia Gray, 1845 (Serpentes: Leptotyphlopidae) from the dry forest of northwestern Peru.

    Science.gov (United States)

    Koch, Claudia; Venegas, Pablo J; Böhme, Wolfgang

    2015-06-02

    Three new blind snake species of the genus Epictia are described based on material collected in the Peruvian Regions Amazonas, Cajamarca and La Libertad. All three species are well differentiated from all congeners based on characteristics of their morphology and coloration. They share 10 scale rows around the middle of the tail and possess two supralabials with the anterior one in broad contact with the supraocular. Epictia septemlineata sp. nov. has 16 subcaudal scales, 257 mid-dorsal scale rows, a yellowish-white rostral, and a black terminal spine. Epictia vanwallachi sp. nov. exhibits 16 subcaudals, 188 mid-dorsal scale rows, a grayish-brown rostral, and a yellow terminal spine. Epictia antoniogarciai sp. nov. features 14-18 subcaudals, 195-208 mid-dorsal scale rows, a bright yellow or yellowish-white rostral, and the terminal spine and terminal portion of the tail yellow. All three species were collected in the interandean dry forest valleys of the Marañón River and its tributaries. This region is an area of endemism and warrants further attention from systematic and conservation biologists.

  16. Fang and Feather: The Origin of Avian-Serpent Imagery at Teotihuacan and Symbolic Interaction With Jaguar Iconography in Mesoamerica

    OpenAIRE

    Math, Kathryn

    2017-01-01

    The central Mexican city of Teotihuacan rose to prominence in the last century BC and lasted for six hundred years. The civic plan was arranged around two main perpendicular avenues. This north-south axis was lined with temples and public monuments. By the third century AD, population was housed in apartment compounds, all precisely aligned with the overarching grid plan (Manzanilla, 1999). On the walls were murals depicting ornately dressed administrators, armor-clad warriors, and fantastic ...

  17. Systematics of Nothopsini (Serpentes, Dipsadidae), with a new species of Synophis from the Pacific Andean slopes of southwestern Ecuador

    Science.gov (United States)

    Pyron, R. Alexander; Guayasamin, Juan M.; Peñafiel, Nicolás; Bustamante, Lucas; Arteaga, Alejandro

    2015-01-01

    Abstract Within Dipsadinae, some recent authors have recognized a tribe Nothopsini containing the genera Diaphorolepis, Emmochliophis, Nothopsis, Synophis, and Xenopholis, on the basis of a number of putative morphological synapomorphies. However, molecular results suggest that Nothopsis, Synophis, and Xenopholis do not form a monophyletic group, while the remaining taxa are unsampled in recent molecular phylogenies. Here, DNA-sequence data for some Diaphorolepis and Synophis species are provided for the first time, as well as additional new sequences for Nothopsis and some Synophis species. Including these and other existing data for nothopsine species, previous studies showing that Nothopsini is not a natural group are corroborated. Nothopsini Cope, 1871 is restricted to Nothopsis. Diaphorolepidini Jenner, 1981 is resurrected and re-delimited to include only Diaphorolepis, Emmochliophis, and Synophis. Finally, Xenopholis remains Dipsadinae incertae sedis. Known material of Diaphorolepidini is reviewed to generate revised and expanded descriptions and diagnoses at the tribe, genus, and species level. Numerous cryptic species are likely present in Synophis bicolor and Synophis lasallei. Finally, a new population from the low-elevation cloud forests of SW Ecuador is reported upon, which is genetically and morphologically distinct from all other species, that is here named Synophis zaheri sp. n. PMID:26798284

  18. Comunicación química en la boa arco iris Epicrates cenchria alvarezi (Serpentes, Boidae

    Directory of Open Access Journals (Sweden)

    Briguera, Verónica

    1994-01-01

    Full Text Available In snakes there are two possible pheromonal sources: skin and cloacal glands. In this work, we tested both secretions in adults of Epicrates cenchria alvarezi as messages transmitters, trying to explain the role that plays this information in the social context of this species. Both secretions have shown to have pheromonal function. Conespecific odors elicited more tongue extrusions than other stimuli did. These results suggest that the snake is capable of discriminating conspecifics based on chemical cues alone.

  19. Actividad de rastreo en Boa constrictor occidentalis (Serpentes: Boidae, un mecanismo de localización de la especie

    Directory of Open Access Journals (Sweden)

    Silmara Cervantes, Raquel

    1999-01-01

    Full Text Available En el presente trabajo se experimentó sobre la habilidad de Boa constrictor occidentalis para discriminar y seguir olores feromonales conespecíficos y heteroespecíficos. Las hembras presentaron elevada frecuencia de extrusiones de lengua hacia los estímulos de olor de piel de macho, piel de hembra y glándula de hembra, mostrando un mayor desplazamiento hacia el estímulo piel de hembra. Los machos respondieron con un incremento en el número de lengüeteos y búsqueda activa de los rastros frente a las secreciones de macho. Ambos sexos manifestaron preferencia por los olores conespecíficos aumentando la intensidad del lengüeteo y el seguimiento activo de rastros, mientras que exhibieron una marcada disminución de la frecuencia de extrusiones de lengua y escaso desplazamiento frente al estímulo heteroespecífico. Los resultados sugieren la estrecha relación existente entre la identificación de un estímulo mediante el lengüeteo y la actividad de rastreo. The ability in adult Boa constrictor occidentalis to discriminate between species and sexes and follow pheromonal trails was tested. Females presented elevated tongue flick rate (T.F.R. to male skin odor, female skin odor and female cloacal secretion. Trailing activity was higher to female skin odor. Males answered with elevated T.F.R. and exhibited active movements and searching of trails to their own secretions —male skin and male cloacal musk—. Both sexes had preferences to conespecific stimuli showing higher T.F.R. and active trailing while they were not interested in heterospecific trails presenting lower T.F.R. and limited movements. Results suggest the relationship between stimuli recognition by tongue flicking and trailing activity.

  20. A new species of slender coralsnake from Colombia, and its clinal an ontogenetic variation (Serpentes, Elapidae: Leptomicrurus

    Directory of Open Access Journals (Sweden)

    William W. Lamar

    2003-09-01

    Full Text Available Leptomicrurus renjifoi is described from tropical semi-deciduous forest of the eastern Colombian llanos. It is one of the smallest species in the genus, is most similar to L. scutiventris, and it may be distinguished from known congeners by a combination of color, pattern, and scale characters. Evidence for the recognition of Leptomicrurus is convincing, although its members were recently thought to comprise a closely related assemblage within Micrurus. A supposedly aberrant specimen of L. scutiventris may indicate clinal or ontogenetic variation in patternLeptomicrurus renjifoi es una nueva especie de serpiente elápida del bosque tropical semi-decíduo de los llanos orientales de Colombia. Es una de las especies más pequeñas del género, se asemeja más a L. scutiventris, y se distingue de sus congéneres por una combinación de color, patrón, y carácteres de escamación. Existe suficiente evidencia morfológica para reconocer Leptomicrurus como género independiente, aunque hasta hace poco sus miembros fueron considerados como un grupo compacto dentro del género Micrurus

  1. Recalculating the steady state conditions of the V-1000 zero-power facility at Kurchatov Institute using Monte Carlo and nodal diffusion codes

    Energy Technology Data Exchange (ETDEWEB)

    Sahlberg, Ville [VTT Technical Research Centre of Finland Ltd, VTT (Finland)

    2017-09-15

    Continuous-energy Monte Carlo reactor physics code Serpent 2 was used to model the critical steady state conditions measured in V-1000 zero-power critical facility at Kurchatov Institute (KI), Moscow in 1990-1992. The Serpent 2 results were compared to measurements and Serpent 2 was used to generate group constants for reactor dynamics code HEXTRAN. The results of a HEXTRAN calculation of the steady state were compared to Serpent 2. The relative power density distribution of the SERPENT2 calculations compared with the measurements was within the statistical accuracy. The comparison of HEXTRAN and Serpent 2 node-wise relative power density distributions showed an accuracy of ±10%.

  2. Analyzing Permutations for AES-like Ciphers: Understanding ShiftRows

    DEFF Research Database (Denmark)

    Beierle, Christof; Jovanovic, Philipp; Lauridsen, Martin Mehl

    2015-01-01

    Designing block ciphers and hash functions in a manner that resemble the AES in many aspects has been very popular since Rijndael was adopted as the Advanced Encryption Standard. However, in sharp contrast to the MixColumns operation, the security implications of the way the state is permuted...... by the operation resembling ShiftRows has never been studied in depth. Here, we provide the first structured study of the influence of ShiftRows-like operations, or more generally, word-wise permutations, in AES-like ciphers with respect to diffusion properties and resistance towards differential- and linear...... normal form. Using a mixed-integer linear programming approach, we obtain optimal parameters for a wide range of AES-like ciphers, and show improvements on parameters for Rijndael-192, Rijndael-256, PRIMATEs-80 and Prøst-128. As a separate result, we show for specific cases of the state geometry...

  3. Design and evaluation of basic standard encryption algorithm modules using nanosized complementary metal oxide semiconductor molecular circuits

    Science.gov (United States)

    Masoumi, Massoud; Raissi, Farshid; Ahmadian, Mahmoud; Keshavarzi, Parviz

    2006-01-01

    We are proposing that the recently proposed semiconductor-nanowire-molecular architecture (CMOL) is an optimum platform to realize encryption algorithms. The basic modules for the advanced encryption standard algorithm (Rijndael) have been designed using CMOL architecture. The performance of this design has been evaluated with respect to chip area and speed. It is observed that CMOL provides considerable improvement over implementation with regular CMOS architecture even with a 20% defect rate. Pseudo-optimum gate placement and routing are provided for Rijndael building blocks and the possibility of designing high speed, attack tolerant and long key encryptions are discussed.

  4. Uso del hábitat por Boa constrictor occidentalis (Serpentes: Boidae durante la estación seca en Córdoba, Argentina

    Directory of Open Access Journals (Sweden)

    Attademo, Andrés

    2004-07-01

    Full Text Available El análisis sobre el uso del hábitat es una herramienta fundamental para la conservación y el manejo de las poblaciones silvestres. Cuantificar los cambios en el uso de recursos asociados con la reproducción puede ofrecer una idea de las fuerzas selectivas que actúan sobre los organismos durante esta fase crítica de su historia de vida. Se ha observado en distintas especies de ofidios que hembras grávidas frecuentan hábitats distintos de los que utilizan hembras no grávidas y machos, por lo que la selección de un ambiente en particular podría estar influenciado por el comportamiento reproductivo. En el presente trabajo evaluamos el uso del hábitat en Boa constrictor occidentalis mediante radiorastreo a nivel de microhábitat durante la estación seca en la localidad de El Quemado, Departamento Pocho, Córdoba. Se marcaron mediante radiotransmisores 14 individuos adultos: 5 hembras reproductivas, 4 hembras no reproductivas y 5 machos reproductivos. Las diferencias en el uso del hábitat observadas en las lampalaguas en función de la condición reproductiva durante la estación seca, reflejarían diferencias en los requerimientos para la termorregulación. El uso que las hembras reproductivas hacen del hábitat les permitiría seleccionar sitios que brinden buenos lugares para asolearse permitiendo obtener temperaturas mayores y óptimas para el desarrollo de los embriones. Habitat use analysis is a basic tool for the conservation and management of wild populations. Quantifying the changes in the use of resources associated with reproduction can offer an insight into the selective forces acting on organisms in this critical phase of life history. Reproduction condition often has obvious effects on habitat use. Reproductive individual females have been observed in habitats different from those frequented by males and non reproductive females. In this study, we evaluate the differential use of habitats in Boa constrictor occidentalis through radio-tracking. Habitat use was evaluated at a microhabitat level during dry season at El Quemado, in the department of Pocho, Córdoba. Fourteen adult individuals were implanted with radio transmitters: 5 reproductive females, 4 non-reproductive females and 5 reproductive males. There were differences in the use of the habitat among these conditions. The differences observed in relation to reproductive functions during the dry season should reveal different thermoregulation requirements in lampalagua. In reptiles, these requirements are among the most influential causes in the selection of a particular habitat. The habitat choice made by reproductive females would allow them to choose adequate places to sunbathe and get higher and optimum temperatures for embryo development.

  5. Redescription of Haemogregarina garnhami (Apicomplexa: Adeleorina) from the blood of Psammophis schokari (Serpentes: Colubridae) as Hepatozoon garnhami n. comb. based on molecular, morphometric and morphologic characters.

    Science.gov (United States)

    Abdel-Baki, Abdel-Azeem S; Al-Quraishy, Saleh; Zhang, J Y

    2014-06-01

    Hepatozoon garnhami n. comb. was redescribed from Schokari sand snakes (Psammophis schokari) collected from Riyadh city in Saudi Arabia. Gametocytes were found in the peripheral blood of 2 of 15 snakes examined. Based on the similar morphological and morphometric characteristics, the same host and a similar host habitat environment, it can be concluded for the first time that the present species is conspecific with Haemogregarina garnhami previously reported from Psammophis shokari aegyptius. To further characterize this parasite, the partial 18S rRNA gene was amplified and sequenced. The sequence analysis also showed that Haemogregarina garnhami should be reassigned into the genus Hepatozoon as Hepatozoon garnhami which has 99.5% (859/863 bp) sequence similarity to Hepatozoon ayorgbor, infecting the erythrocytes of Python regius in Ghana. Phylogenetic analysis showed that H. garnhami formed a mixed clade with Hepatozoon spp. from geckos, snakes and rodents and ophidian Hepatozoon spp. did not form a separated phylogenetic unit. Also, Psammophis schokari-infecting Hepatozoon contained several different genetic lineages. To our knowledge, the present work extends the geographic distribution of H. garnhami and is the first report of Hepatozoon infection in snakes from Saudi Arabia.

  6. As faunas de serpentes da América do Sul e Austrália : ecologia, biogeografia e evolução

    OpenAIRE

    Leite, Davi Lima Pantoja

    2014-01-01

    Este trabalho avalia comparativamente os cenários físicos e ecológicos em que se formaram as comunidades biológicas da América do Sul e Austrália, e reúne os alicerces teóricos para comparações biológicas entre estes continentes: (1) fornecendo uma lista da bibliografia básica; (2) descrevendo a história geográfica e climática de ambos os continentes e seus ambientes atuais; e (3) destacando os elementos que dão suporte às comparações biológicas entre América do Sul e Austrália. A estrutura d...

  7. Genetic divergence and diversity in the Mona and Virgin Islands Boas, Chilabothrus monensis (Epicrates monensis) (Serpentes: Boidae), West Indian snakes of special conservation concern.

    Science.gov (United States)

    Rodríguez-Robles, Javier A; Jezkova, Tereza; Fujita, Matthew K; Tolson, Peter J; García, Miguel A

    2015-07-01

    Habitat fragmentation reduces the extent and connectivity of suitable habitats, and can lead to changes in population genetic structure. Limited gene flow among isolated demes can result in increased genetic divergence among populations, and decreased genetic diversity within demes. We assessed patterns of genetic variation in the Caribbean boa Chilabothrus monensis (Epicrates monensis) using two mitochondrial and seven nuclear markers, and relying on the largest number of specimens of these snakes examined to date. Two disjunct subspecies of C. monensis are recognized: the threatened C. m. monensis, endemic to Mona Island, and the rare and endangered C. m. granti, which occurs on various islands of the Puerto Rican Bank. Mitochondrial and nuclear markers revealed unambiguous genetic differences between the taxa, and coalescent species delimitation methods indicated that these snakes likely are different evolutionary lineages, which we recognize at the species level, C. monensis and C. granti. All examined loci in C. monensis (sensu stricto) are monomorphic, which may indicate a recent bottleneck event. Each population of C. granti exclusively contains private mtDNA haplotypes, but five of the seven nuclear genes assayed are monomorphic, and nucleotide diversity is low in the two remaining markers. The faster pace of evolution of mtDNA possibly reflects the present-day isolation of populations of C. granti, whereas the slower substitution rate of nuDNA may instead mirror the relatively recent episodes of connectivity among the populations facilitated by the lower sea level during the Pleistocene. The small degree of overall genetic variation in C. granti suggests that demes of this snake could be managed as a single unit, a practice that would significantly increase their effective population size. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Nova espécie de Helicops Wagler, 1830 (Serpentes, Colubridae do rio Tapajós, Amazônia, Brasil

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    Jossehan Galúcio da Frota

    2005-10-01

    Full Text Available Within the 14 species of Helicops known, five of them are distributed in Brazilian Amazon region. Here I describe a new species of Helicops based on three specimens from Tapajós river, western Pará state, Brazil. The new species is characterized by an opaque, green-moss uniform coloration on the vertebral and paravertebral scales, extending until the end of the tail, becoming yellow-greenish in the paraventral region, without spots, blotches or stripes on the whole dorsum. It differs from all species known of Helicops by the dorsal color pattern. Morphologically, the new species seems like H. leopardinus (as indicated by the number of dorsal scale rows, the number of ventral scales, and the number of teeth, but it has smaller lobes in the hemipenis and a very distinct color pattern. Illustrations of the type material and a dicotomic key are presented to help to distinguish the new species from other species of Helicops from Brazilian Amazon region.

  9. Sexual dimorphism in development and venom production of the insular threatened pit viper Bothrops insularism (Serpentes: Viperidae of Queimada Grande Island, Brazil

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    S.R. Travaglia-Cardoso

    2010-09-01

    Full Text Available Bothrops insularis is a threatened snake endemic to Queimada Grande Island, southern coast of São Paulo, Brazil, and the occurrence of sexual abnormalities in females (females with functional ovaries and rudimentary hemipenis has been reported in this population. To date there are few data regarding developmental features of this particular species. The aim of this study was to follow some developmental features in specimens maintained in captivity for seven years in the Herpetology Laboratory at Instituto Butantan, São Paulo, Brazil. We verified a pronounced sexual dimorphism in development and venom production in the specimens analyzed. In this regard, females showed greater length, mass and amount of venom in comparison to males. Our results suggest a possible niche partitioning between the sexes that reduces (or minimizes intraspecific disharmonic interactions (eg. competition on their small living area (Queimada Grande Island. Taken together, our data suggest that males and females probably are divergent in their diets, with females feeding preferentially on endothermic prey (such as migratory birds, while males maintain the juvenile diet (with the major items being ectothermic prey.

  10. Description of Eimeria arabukosokokensis sp. n. (Apicomplexa: Eimeriidae) from Telescopus semiannulatus (Serpentes: Colubridae) with notes on eimerian coccidia from snakes of Eastern Kenya

    Czech Academy of Sciences Publication Activity Database

    Šlapeta, Jan Roger; Modrý, David; Ashe, J.; Koudela, Břetislav

    2003-01-01

    Roč. 50, č. 1 (2003), s. 23-30 ISSN 0015-5683 R&D Projects: GA ČR GA524/00/P015 Institutional research plan: CEZ:AV0Z6022909 Keywords : Coccidia * Caryospora * Eimeria Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 0.469, year: 2003

  11. Neutralización del efecto hemorrágico inducido por veneno de Bothrops asper (Serpentes: Viperidae por extractos de plantas tropicales

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    Oscar Castro

    1999-09-01

    Full Text Available Se evaluó la capacidad de extractos orgánicos de 48 especies de plantas costarricenses para neutralizar la actividad hemorrágica del veneno de la serpiente Bothrops asper (terciopelo. Los extractos se evaluaron mediante un bioensayo basado en inyecciones intradérmicas de veneno en ratones, o de mezclas veneno-extracto, seguidas de la cuantificación macroscópica de la hemorragia. Se observó una inhibición total de la hemorragia con los extractos etanólico, de acetato de etilo y acuoso de Bursera simaruba, Clusia torresii, C. palmana, Croton draco, Persea americana, Phoebe brenesii, Pimenta dioica, Sapindus saponaria, Smilax cuculmeca y Virola koschnyi. El análisis químico de estos extractos permitió identificar catequinas, flavonas, antocianinas y taninos condensados, los cuales podrían jugar un papel en la inhibición del efecto hemorrágico debido a la capacidad de quelar el ion zinc requerido por las metaloproteinasas hemorrágicas para su acción.Organic extracts representing 48 species included in 30 families of Costa Rican tropical plants were evaluated for their ability to neutralize hemorrhagic activity induced by the venom of the snake Bothrops asper. A bioassay in mice was used, based on intradermal injection of either venom or venom-extract mixtures followed by the measurement of hemorrhagic areas. Total inhibition of hemorrhage was observed with the ethanolic, ethyl acetate and aquous extracts of Bursera simaruba, Clusia torresii, C. palmana, Croton draco, Persea americana, Phoebe brenesii, Pimenta dioica, Sapindus saponaria, Smilax cuculmeca and Virola koschnyi. Chemical analysis of these extracts identified catequines, flavones, anthocyanines and condensated tannins, which may be responsible for the inhibitory effect observed, probably owing to the chelation of the zinc required for the catalytic activity of venom’s hemorrhagic metalloproteinases.

  12. "So it really does exist-the sea-Serpent we've never believed in!" Ferenczi's influence on Freud revisited.

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    Bonomi, Carlo

    2013-12-01

    In the last phase of his work, Ferenczi created a new language for trauma, based on the fragmentation of mental life. In the paper on "The principles of relaxation and neocatharsis," Ferenczi reformulated the goal of analysis by proposing that "no analysis can be regarded … as complete unless we have succeed in penetrating the traumatic material", where the "traumatic material" was not to be sought in the neurotic reactions and adaptive solutions of the ego but in more primitive reactions, such as the psychotic turning away from reality, splitting, and fragmentation. This was exactly the material that Freud assimilated in the essay "A disturbance of memory on the Acropolis", after the death of Ferenczi. Freud visited Athens in 1904, and the walk up to the Parthenon represented the successful coronation of his self-analysis. Actually, the hallucination turned out to be so uncanny that he never again visited Athens. In a letter to Fliess, written shortly before the meeting in Nuremberg, on January 24, 1897, Freud reported on a case history turning on a "scene about the circumcision of a girl," who later was convincingly identified by Schur as Emma Eckstein. Did Freud have the germinal idea that Emma Eckstein's hallucination of the penis contained the wish to overcome her trauma and the hope to have a restored genital? Is this the holy visitation, which haunted him on the Acropolis? Why did he give up the profound insight that the dreams of gigantic snakes had a traumatic origin?

  13. Contribuição à biologia de serpentes da Bahia, Brasil: I. vivíparas Contribution to reproductive biology of snakes in Bahia, Brazil: I. viviparous

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    Rejane Maria Lira-da-Silva

    1994-01-01

    Full Text Available Great part of lhe avaiable data about snakes reprodution refers to species coming from subtropical and temperate regions. In Brazil, the data is rather rare and can be found in various works where information is restricted. Results from studies developed with five viviparous snakes - Crotalus durissus cascavella (Wagler, 1824. Bothrops erythromelas(Amaral, 1923, B. leucurus (Wagler, 1824, Helicops leopardinus (Schlegel, 1873 and Thamnodynastes strigilis (Thiinberg, 1787 - which come from the Northeast of Brazil (Bahia are described. Data about pregnancy and birth, number, sex ratio, length and weight of neonates is given and discussed.

  14. Effectiveness of phylogenomic data and coalescent species-tree methods for resolving difficult nodes in the phylogeny of advanced snakes (Serpentes: Caenophidia).

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    Pyron, R Alexander; Hendry, Catriona R; Chou, Vincent M; Lemmon, Emily M; Lemmon, Alan R; Burbrink, Frank T

    2014-12-01

    Next-generation genomic sequencing promises to quickly and cheaply resolve remaining contentious nodes in the Tree of Life, and facilitates species-tree estimation while taking into account stochastic genealogical discordance among loci. Recent methods for estimating species trees bypass full likelihood-based estimates of the multi-species coalescent, and approximate the true species-tree using simpler summary metrics. These methods converge on the true species-tree with sufficient genomic sampling, even in the anomaly zone. However, no studies have yet evaluated their efficacy on a large-scale phylogenomic dataset, and compared them to previous concatenation strategies. Here, we generate such a dataset for Caenophidian snakes, a group with >2500 species that contains several rapid radiations that were poorly resolved with fewer loci. We generate sequence data for 333 single-copy nuclear loci with ∼100% coverage (∼0% missing data) for 31 major lineages. We estimate phylogenies using neighbor joining, maximum parsimony, maximum likelihood, and three summary species-tree approaches (NJst, STAR, and MP-EST). All methods yield similar resolution and support for most nodes. However, not all methods support monophyly of Caenophidia, with Acrochordidae placed as the sister taxon to Pythonidae in some analyses. Thus, phylogenomic species-tree estimation may occasionally disagree with well-supported relationships from concatenated analyses of small numbers of nuclear or mitochondrial genes, a consideration for future studies. In contrast for at least two diverse, rapid radiations (Lamprophiidae and Colubridae), phylogenomic data and species-tree inference do little to improve resolution and support. Thus, certain nodes may lack strong signal, and larger datasets and more sophisticated analyses may still fail to resolve them. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Composição e história natural das serpentes de Cerrado de Itirapina, São Paulo, sudeste do Brasil

    OpenAIRE

    SAWAYA, Ricardo Jannini; MARQUES, Otavio Augusto Vuolo; MARTINS, Marcio

    2008-01-01

    Neotropical snake assemblages present high species richness and complex structures. The Cerrado is the second largest biome in Brazil, and was included among the 25 World's biodiversity hotspots. In southeastern Brazil, the remnant Cerrado areas have suffered intense destruction, and presently less than 2% of Cerrado natural vegetation remain in São Paulo state. Virtually no detailed study on Cerrado snakes was carried out in this region. The Itirapina region has one of the last well preserve...

  16. The snake assemblage (Squamata: Serpentes) of a Cerrado-Caatinga transition area in Castelo do Piauí, state of Piauí, Brazil

    OpenAIRE

    Rodrigues, Francílio da Silva; Prudente, Ana Lúcia da Costa

    2011-01-01

    This study records and analyzes the diversity and structure of a snake assemblage in a transition area between Cerrado and Caatinga, in the municipality of Castelo do Piauí, state of Piauí, comparing the distribution and similarity of the species composition with other open localities already studied in Brazil. We used three complementary sampling methods: time constrained search (TCS), pitfall traps with drift fences (PFT), and incidental encounters (IE). During the TCS and PFT, 912 hours/ob...

  17. The snake assemblage (Squamata: Serpentes of a Cerrado-Caatinga transition area in Castelo do Piauí, state of Piauí, Brazil

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    Francílio da Silva Rodrigues

    2011-08-01

    Full Text Available This study records and analyzes the diversity and structure of a snake assemblage in a transition area between Cerrado and Caatinga, in the municipality of Castelo do Piauí, state of Piauí, comparing the distribution and similarity of the species composition with other open localities already studied in Brazil. We used three complementary sampling methods: time constrained search (TCS, pitfall traps with drift fences (PFT, and incidental encounters (IE. During the TCS and PFT, 912 hours/observer and 6,468 days/trap were used, respectively. We estimated 23 species of snakes for the locality, although only 19 species were recorded. Philodryas nattereri Steindachner, 1870 (n = 10, Liophis poecilogyrus (Schlegel, 1837 (n = 9, Liophis viridis Günther, 1862 (n = 8 and Thamnodynastes sp. (n = 8 were the most abundant species. Terrestrial, cryptozoic, and diurnal snakes predominated in the assemblage (Boidae = 2 species, Dipsadidae = 12, Colubridae = 2, Elapidae = 1, Viperidae = 2. The results indicate that the fauna of the locality is similar with that of other open formations, especially the Caatinga, corroborating previous floristic studies. Comparisons between snake assemblages analyzed by different authors suggest structural differences between the assemblages of the Cerrado and the Caatinga, contradicting the hypothesis of mixed composition of fauna in these biomes.

  18. Podem as serpentes conviver com as pombas?Uma reflexão filosófica sobre a ética na política

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    Cinara Nahra

    2009-12-01

    Full Text Available The purpose of this article is to discuss the relationship between ethics and politics taking as the starting point the differences between Kant´s and Machiavelli´s views. I will also discuss here the role of the contemporary State, as well as I will put forward what I call the “6c model” namely the immoral practices which are largely used in Brazilian politics, especially at the time of elections, i.e., exchange of favours, corporative vote ,authoritarianism, control and manipulation of information, fantasy and corruption. Finally, I intend to show the necessity of adopting a model inspired by Kant that subordinates politics to a rational morality.

  19. Feeding ecology of Erythrolamprus jaegeri jaegeri (Günter, 1858) and Erythrolamprus poecilogyrus sublineatus (Cope, 1860) in the coastal zone of Subtropical Brazil (Serpentes, Dipsadidae).

    Science.gov (United States)

    Corrêa, Daniele N; Quintela, Fernando M; Loebmann, Daniel

    2016-03-01

    The snakes Erythrolamprus jaegeri jaegeri and Erythrolamprus poecilogyrus sublineatus are sympatric and syntopic in the coastal region of southern Brazil. Herein, we analyzed the diet composition to evaluate the niche breadth and the prey selection by both species. We examined 192 specimens, and analysis of stomach contents revealed that both species predominantly consume anurans. However, the diet of E. j. jaegeri consists mainly of fish and amphibians, whereas that of E. p. sublineatus is broader, including fish, amphibians, reptiles and mammals. The Standardized Levins Index presented lower values for E. j. jaegeri (BA = 0.17) than for E. p. sublineatus (BA = 0.61), evidencing specialist and generalist strategies for each species, respectively. Regarding prey selection, E. p. sublineatus presented a larger snout-vent length, head, mouth and lower jaw than E. j. jaegeri and fed on larger prey. In addition, positive correlations between the size and weight of predators and prey were confirmed in both species. The results show the development of different mechanisms for co-occurrence of the two species, such as prey selection by size, such that the size of the predator is related to the size of their prey, or by developing different strategies to decrease niche overlap between species.

  20. Shades of the Rainbow Serpent? A KhoeSan Animal between Myth and Landscape in Southern Africa—Ethnographic Contextualisations of Rock Art Representations

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    Sian Sullivan

    2014-06-01

    Full Text Available The snake is a potent entity in many cultures across the world, and is a noticeable global theme in rock art and inscribed landscapes. We mobilise our long-term ethnographic research with southern African KhoeSan peoples to situate and interpret the presence of snake motifs in the region’s rock art. We contextualise the snake as a transformative ontological mediator between everyday and “entranced” KhoeSan worlds (those associated with “altered states of consciousness”, to weave together both mythological and shamanistic interpretations of southern African rock art. Ethnographic explorations of experiences of snakes as both an aspect of natural history and the physical environment, and as embodiments of multiplicitous and mythical meaning by which to live and understand life, shed light on the presence of snakes and associated snake-themes in southern African rock art. By drawing on ethnographic material, and in conjunction with review of literature, we highlight a dynamic assemblage of extant associations between snakes, rain, water, fertility, blood, fat, transformation, dance and healing. We suggest that these extant associations have explanatory potential for understanding the meaning of these themes in the rock art created by the ancestors of contemporary KhoeSan peoples. Our paper contributes to a live debate regarding the interpretive relevance of ethnography for understanding rock art representations from the past.

  1. Troublesome Trimes: Potential cryptic speciation of the Trimeresurus (Popeia) popeiorum complex (Serpentes: Crotalidae) around the Isthmus of Kra (Myanmar and Thailand).

    Science.gov (United States)

    Mulcahy, Daniel G; Lee, Justin L; Miller, Aryeh H; Zug, George R

    2017-11-13

    The taxonomic identity of the Trimeresurus (Popeia) popeiorum complex from the Isthmus of Kra and to the north was investigated. Several studies over the last decade have produced several specimens and associated mtDNA sequence data for a variety of individuals of the T. popeiorum and "T. sabahi" complexes. Here, we combine four mitochondrial genes (12S, 16S, ND4, and CytB) from all available specimens in GenBank with the addition of five new specimens collected from the mainland, Tanintharyi Region of Myanmar. Maximum Likelihood and Bayesian analyses identified that T. popeiorum sensu lato is paraphyletic with two geographically distinct clades: a northern clade representing populations from northern Myanmar, Laos and northern Thailand and a southern clade representing samples from the Tanintharyi Region and adjacent west Thailand. While the two clades have considerable genetic distance, they appear to be morphologically identical, leading to the hypothesis that the southern clade represents a cryptic, undescribed species. Because they appear to be cryptic species and the limitation of only five specimens from the southern lineage, this does not permit us to formally describe the new species. In accordance to past molecular studies, we uncovered paraphyly and lack of genetic support for the validity of taxa within the T. sabahi complex. However, we suggest recognizing these populations as subspecies within T. sabahi.

  2. A new species of Mud Snake (Serpentes, Homalopsidae, Gyiophis Murphy & Voris, 2014) from Myanmar with a first molecular phylogenetic assessment of the genus.

    Science.gov (United States)

    Quah, Evan S H; Grismer, L Lee; Wood, Perry L Jr; Thura, Myint Kyaw; Zin, Thaw; Kyaw, Htet; Lwin, Ngwe; Grismer, Marta S; Murdoch, Matthew L

    2017-03-06

    A newly discovered species of homalopsid snake from the genus Gyiophis Murphy & Voris is described from the lowlands of Mawlamyine District in Mon state, southeastern Myanmar. Gyiophis salweenensis sp. nov. is presumed to be closely related to G. maculosa Blanford and G. vorisi Murphy based on the similarities in pholidosis and patterning but can be separated from G. maculosa by the shape of its first three dorsal scale rows that are square, ventral scale pattern that lacks a central spot, and a faint stripe on dorsal scale rows 1-4. It can be further distinguished from G. vorisi by its lower number of ventral scales (129 vs. 142-152), lower number of subcaudals (30/29 vs. 41-58), narrow rostral scale, and having more rows of spots on the dorsum (four vs. three). A preliminary molecular analysis using 1050 base pairs of cytochrome b (cytb) recovered G. salweenensis sp. nov. as the sister species to the Chinese Mud Snake (Myrrophis chinensis). G. maculosa and G. vorisi were unavailable for the analysis. The discovery of G. salweenensis sp. nov. highlights the need for more surveys into the herpetological diversity of eastern Myanmar which remains very much underestimated.

  3. Tantilla melanocephala (Linnaeus, 1758 - (Serpentes: Colubridae. Primeros registros para la Provincia de Jujuy y confirmación de su presencia en el noroeste argentino

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    Burgos Gallardo, Freddy

    2012-08-01

    Full Text Available República Argentina, provincia de Jujuy, Departamento Ledesma, Parque Nacional Calilegua, Camino de acceso a Yacimiento Caimancito (23°39’24.55”S; 64°34’49.78”O; 440 m s.n.m. Coordenadas calculadas mediante Google Earth. Colectores: Baltazar Ramos y Francisco Gallardo. 12 de abril de 2011. (SVL: 270 mm; LT: 370 mm depositado en la Colección del Laboratorio de Genética Evolutiva, Instituto de Biología Subtropical (UNaM-CONICET, Posadas, Misiones, Argentina (LGE 02577, Fig. 1.

  4. Snake venoms components with antitumor activity in murine melanoma cells; Componentes derivados de venenos de serpentes com acao antitumoral em celulas de melanoma murino

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Rodrigo Guimaraes

    2012-07-01

    Despite the constant advances in the treatment of cancer, this disease remains one of the main causes of mortality worldwide. So, the development of new treatment modalities is imperative. Snake venom causes a variety of biological effects because they constitute a complex mixture of substances as disintegrins, proteases (serine and metalo), phospholipases A2, L-amino acid oxidases and others. The goal of the present work is to evaluate a anti-tumor activity of some snake venoms fractions. There are several studies of components derived from snake venoms with this kind of activity. After fractionation of snake venoms of the families Viperidae and Elapidae, the fractions were assayed towards murine melanoma cell line B16-F10 and fibroblasts L929. The results showed that the fractions of venom of the snake Notechis ater niger had higher specificity and potential antitumor activity on B16-F10 cell line than the other studied venoms. Since the components of this venom are not explored yet coupled with the potential activity showed in this work, we decided to choose this venom to develop further studies. The cytotoxic fractions were evaluated to identify and characterize the components that showed antitumoral activity. Western blot assays and zymography suggests that these proteins do not belong to the class of metallo and serine proteinases. (author)

  5. Una nueva especie de serpiente del género Sibon (Serpentes: Colubridae de la vertiente del Caribe de Costa Rica

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    Alejandro Solórzano

    2001-12-01

    Full Text Available Sibon lamari, a new species of colubrid snake from northeastern Costa Rica is described on the basis of six specimens. The new form differs from the closely allied S. annulatus in color pattern, head size, subcaudal count, and number of labials bordering eye-orbit. This is the third species of Sibon, together with S. argus and S. longifrenis, possessing a green dorsal ground color in Costa Rica. Sibon lamari coexists sympatrically with S. annulatus, S. argus, S. longifrenis and S. nebulatus at the locality of Guayacán de Siquirres (Limón Province

  6. A low-cost method to test cytotoxic effects of Crotalus vegrandis (Serpentes: Viperidae venom on kidney cell cultures Un método de bajo costo para probar los efectos citotóxicos del veneno de Crotalus vegrandis (Serpentes: Viperidae en cultivos de células renales

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    María E. Girón

    2005-06-01

    Full Text Available The pathogenesis of the renal lesion upon envenomation by snakebite has been related to myolysis, hemolysis, hypotension and/or direct venom nephrotoxicity caused by the venom. Both primary and continuous cell culture systems provide an in vitro alternative for quantitative evaluation of the toxicity of snake venoms. Crude Crotalus vegrandis venom was fractionated by molecular exclusion chromatography. The toxicity of C. vegrandis crude venom, hemorrhagic, and neurotoxic fractions were evaluated on mouse primary renal cells and a continuous cell line of Vero cells maintained in vitro. Cells were isolated from murine renal cortex and were grown in 96 well plates with Dulbecco's Modified Essential Medium (DMEM and challenged with crude and venom fractions. The murine renal cortex cells exhibited epithelial morphology and the majority showed smooth muscle actin determined by immune-staining. The cytotoxicity was evaluated by the tetrazolium colorimetric method. Cell viability was less for crude venom, followed by the hemorrhagic and neurotoxic fractions with a CT50 of 4.93, 18.41 and 50.22 µg/mL, respectively. The Vero cell cultures seemed to be more sensitive with a CT50 of 2.9 and 1.4 µg/mL for crude venom and the hemorrhagic peak, respectively. The results of this study show the potential of using cell culture system to evaluate venom toxicity.La patogénesis de la lesion renal ha sido relacionada a la miolisis, hemólisis, hipotensión y/o el efecto directo del veneno. Tanto el cultivo primario o el cultivo celular continuo proveen una alternativa in vitro para la evaluación cuantitativa de la toxicidad de venenos de serpiente. El veneno crudo de Crotalus vegrandis fue fraccionado por una cromatografía de exclusión molecular. La toxicidad del veneno crudo de C. vegrandis, sus fracciones hemorrágicas y neurotóxicas fueron evaluadas en células renales primarias de ratón y una línea continua de células Vero mantenidas in vitro. Las células fueron aisladas de la corteza renal murina y se cultivaron en placas de 96 pozos con medio Dulbecco (DMEM. Allí fueron tratadas con el veneno crudo y sus fracciones. Las células de la corteza renal murina tuvieron una morfología de células epiteliales y la mayoría se tiñeron con un anticuerpo anti-músculo actina. La citotoxicidad fue evaluada por el método colorimétrico del tetrazolium. La viabilidad de las células fue menor en las células tratadas con el veneno crudo, seguida por la fracción hemorrágica y neurotóxica, con un CT50 de 4.93, 18.41 y 50.22 µg/mL, respectivamente. Los cultivos de células Vero parecieron ser más sensibles con un CT50 de 2.9 y 1.4 µg/mL para el veneno crudo y el pico hemorrágico, respectivamente. Los resultados de este estudio muestran la potencialidad de usar sistemas de cultivo celular para evaluar la toxicidad de los venenos.

  7. The Seminole Serpent Warrior At Miramar, FL, Shows Settlement Locations Enabled Environmental Monitoring Reminiscent Of the Four-corners Kokopelli-like EMF Phenomena, and Related to Earthquakes, Tornados and Hurricanes.

    Science.gov (United States)

    Balam Matagamon, Chan; Pawa Matagamon, Sagamo

    2004-03-01

    Certain Native Americans of the past seem to have correctly deduced that significant survival information for their tradition-respecting cultures resided in EMF-based phenomena that they were monitoring. This is based upon their myths and the place or cult-hero names they bequeathed us. The sites we have located in FL have been detectable by us visually, usually by faint blue light, or by the elicitation of pin-like prickings, by somewhat intense nervous-system response, by EMF interactions with aural electrochemical systems that can elicit tinitus, and other ways. In the northeast, Cautantowit served as a harbinger of Indian summer, and appears to be another alter ego of the EMF. The Miami, FL Tequesta site along the river clearly correlates with tornado, earthquake and hurricane locations. Sites like the Mohave Deserts giant man may have had similar significance.

  8. A new blind snake of the genus Letheobia (Serpentes: Typhlopidae) from Rwanda with redescriptions of L. gracilis (Sternfeld, 1910) and L. graueri (Sternfeld, 1912) and the introduction of a non-invasive preparation procedure for scanning electron microscopy in zoology.

    Science.gov (United States)

    Dehling, J Maximilian; Hinkel, Harald H; Ensikat, Hans-jÜrgen; Babilon, Kenny; Fischer, Eberhard

    2018-02-11

    A new species of blind snake in the genus Letheobia is described from Akagera National Park in eastern Rwanda. The new species is most similar to species of the L. gracilis complex, particularly L. gracilis and L. graueri. It differs from all other species of the genus by a unique combination of morphological characters, including the highest number of middorsal scale rows (834) and the most extreme elongation (total-length/midbody-width ratio 131) of all species in the genus and of any species of snake in the world; 22-22-22 longitudinal scale rows; snout in dorsal profile rounded, in lateral profile bluntly rounded with an angular horizontal edge ventrally; rostral broad, posteriorly rounded; eyes invisible; supralabial imbrication pattern T-0; tail short (1.3 percent of total length) with an apical spine; and a pink life colouration. The holotype of the new species was collected in gallery forest at a lake shore surrounded by savanna at 1300 m elevation. We produced scanning electron microscope images of the heads of the investigated specimens applying a liquid-substitution preparation procedure which does not require coating or drying and thus does not irreversibly damage the investigated samples. The obtained images allow an easy and more accurate examination of the scalation.

  9. Ocorrência de Hepatozoon spp. (Apicomplexa, Hepatozoidae em serpentes do gênero Bothrops de cativeiro Occurrence of Hepatozoon spp. (Apicomplexa, Hepatozoidae in snakes of genus Bothrops in captivity

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    V. Glaser

    2008-10-01

    Full Text Available The occurrence of Hepatozoon gamont in the blood cells of Bothrops jararaca and B. jararacussu in captivity was analyzed. The prevalence of infection by Hepatozoon spp. was 50% and few erythrocytes contained the gamonts. Results suggest that the infection by Hepatozoon spp. occurred in the natural environment or after the captivity.

  10. Descrição de uma nova espécie de Thamnodynastes Wagler, 1830 (Serpentes, Colubridae do nordeste brasileiro, com comentários sobre o gênero.

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    Francisco L. Franco

    2002-12-01

    Full Text Available Thamnodynastes almae sp. nov. is described based on three specimens from Rodelas municipality, state of Bahia, Northeastern Brazil. The new species can be diagnosed by its pale coloration and keeled dorsal scales arranged in 19 rows at midbody and 15 rows posteriorly. Characters for distinguishing T. almae from other brazilian species of Thamnodynastes are provided.

  11. Snakebites by Crotalus durissus ssp in children in Campinas, São Paulo, Brazil Acidentes por serpentes Crotalus durisssus ssp em crianças em Campinas, São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Fábio BUCARETCHI

    2002-01-01

    Full Text Available From January, 1984 to March, 1999, 31 children under 15 y old (ages 1-14 y, median 8 y were admitted after being bitten by rattlesnakes (Crotalus durissus ssp. One patient was classified as "dry-bite", 3 as mild envenoming, 9 as moderate envenoming and 18 as severe envenoming. Most patients had neuromuscular manifestations, such as palpebral ptosis (27/31, myalgia (23/31 and weakness (20/31. Laboratory tests suggesting rhabdomyolysis included an increase in total blood creatine kinase (CK, 28/29 and lactate dehydrogenase (LDH, 25/25 levels and myoglobinuria (14/15. The main local signs and symptoms were slight edema (20/31 and erythema (19/31. Before antivenom (AV administration, blood coagulation disorders were observed in 20/25 children that received AV only at our hospital (incoagulable blood in 17/25. AV early reactions were observed in 20 of these 25 cases (9/9 patients not pretreated and 11/16 patients pretreated with hydrocortisone and histamine H1 and H2 antagonists. There were no significant differences in the frequency of patients with AV early reactions between the groups that were and were not pretreated (Fisher's exact test, p = 0.12. Patients admitted less than and more than 6 h after the bite showed the same risk of developing severe envenoming (Fisher's exact test, p = 1. No children of the first group (De janeiro de 1984 a março de 1999, 31 crianças com menos de 15 anos de idade (1 a 14 anos, mediana = 8 anos foram admitidas após terem sido picadas por Crotalus durissus ssp. Uma criança não apresentou manifestações clínicas de envenenamento, enquanto 3 foram classificadas como acidente leve, 9 como moderado e 18 como grave. A maioria das crianças apresentou envolvimento neuromuscular, tais como ptose palpebral (27/31, mialgia (23/31 e fraqueza (20/31. Alterações laboratoriais sugerindo rabdomiólise também foram observadas, como aumento das enzimas séricas CK (28/29 e LDH (25/25 e mioglobinúria (14/15. As principais manifestações locais observadas foram edema discreto (20/31 e eritema (19/31. Alterações da coagulação, antes da administração da soroterapia antiveneno (SAV, foram observadas em 20 das 25 crianças que receberam a SAV exclusivamente em nosso hospital (sangue incoagulável em 17/25. Reações precoces à SAV foram observadas em 20 destes 25 casos, em todos os pacientes não pré-tratados (N = 9 e em 11 dentre os 16 pré-tratados com antagonistas H1 e H2 da histamina e hidrocortisona. Não foram constatadas diferenças estatísticas significativas comparando-se a freqüência de reações precoces à SAV entre os grupos que receberam ou não o pré-tratamento (teste exato de Fisher, p = 0,12. Pacientes atendidos com menos ou mais de 6 horas após o acidente apresentaram o mesmo risco quanto a evolução para casos graves (teste exato de Fisher, p = 1, não se observando complicações graves no 1º grupo (< 6 h, enquanto 3/6 admitidos mais de 6 horas após a picada evoluíram com insuficiência renal aguda. Pacientes picados na perna apresentaram um maior risco de desenvolver acidentes graves (teste exato de Fisher, p = 0,04. Houve uma associação significativa entre os níveis séricos das enzimas CK e LDH total e gravidade (teste U de Mann-Whitney, CK, p < 0,001; LDH, p < 0,001. Nenhum óbito foi registrado.

  12. Voir une chenille, dessiner un serpent à plumes. Une relecture analogique de l’hybridité et des êtres imaginaires en Mésoamérique préhispanique

    OpenAIRE

    Karadimas, Dimitri

    2016-01-01

    En prenant le parti d’analyser les êtres imaginaires et les figurations d’hybrides en Mésoamérique comme des retranscriptions imagées d’êtres réels selon des principes de l’analogie formelle, cette contribution se propose de revenir sur la figure de Quetzalcóatl, tant dans l’iconographie de Teotihuacan que dans celle, plus tardive, des Aztèques. Après avoir passé en revue certains principes de la perception intervenant dans le mode de nomination des espèces, leur application à des matériaux i...

  13. ANÁLISIS Y COMPARACIÓN DE LOS ALGORITMOS DE CIFRADOS SIMÉTRICO EN PLATAFORMAS WINDIWS

    OpenAIRE

    Carrera Albán, Thruman Wladimir

    2016-01-01

    El objetivo principal que guía el diseño de cualquier algoritmo de cifrado debe ser la seguridad contra ataques no autorizados. Sin embargo, para todas las aplicaciones prácticas, el rendimiento y la velocidad también son preocupaciones importantes. Estas son las dos características principales que diferencian un algoritmo de cifrado de otro. Este documento proporciona la comparación de rendimiento entre dos de los algoritmos de cifrado más utilizados: AES (Rijndael) y Blowfish. La comparació...

  14. On the Design of Error-Correcting Ciphers

    Directory of Open Access Journals (Sweden)

    Mathur Chetan Nanjunda

    2006-01-01

    Full Text Available Securing transmission over a wireless network is especially challenging, not only because of the inherently insecure nature of the medium, but also because of the highly error-prone nature of the wireless environment. In this paper, we take a joint encryption-error correction approach to ensure secure and robust communication over the wireless link. In particular, we design an error-correcting cipher (called the high diffusion cipher and prove bounds on its error-correcting capacity as well as its security. Towards this end, we propose a new class of error-correcting codes (HD-codes with built-in security features that we use in the diffusion layer of the proposed cipher. We construct an example, 128-bit cipher using the HD-codes, and compare it experimentally with two traditional concatenated systems: (a AES (Rijndael followed by Reed-Solomon codes, (b Rijndael followed by convolutional codes. We show that the HD-cipher is as resistant to linear and differential cryptanalysis as the Rijndael. We also show that any chosen plaintext attack that can be performed on the HD cipher can be transformed into a chosen plaintext attack on the Rijndael cipher. In terms of error correction capacity, the traditional systems using Reed-Solomon codes are comparable to the proposed joint error-correcting cipher and those that use convolutional codes require more data expansion in order to achieve similar error correction as the HD-cipher. The original contributions of this work are (1 design of a new joint error-correction-encryption system, (2 design of a new class of algebraic codes with built-in security criteria, called the high diffusion codes (HD-codes for use in the HD-cipher, (3 mathematical properties of these codes, (4 methods for construction of the codes, (5 bounds on the error-correcting capacity of the HD-cipher, (6 mathematical derivation of the bound on resistance of HD cipher to linear and differential cryptanalysis, (7 experimental comparison

  15. Tools and applications for core design and shielding in fast reactors

    International Nuclear Information System (INIS)

    Rachamin, Reuven

    2013-01-01

    Outline: • Modeling of SFR cores using the Serpent-DYN3D code sequence; • Core shielding assessment for the design of FASTEF-MYRRHA; • Neutron shielding studies on an advanced Molten Salt Fast Reactor (MSFR) design

  16. 1) Mis teile praeguses eesti kirjanduses ei meeldi? 2) Mida tuleks teha, et asi läheks nii, nagu teile meeldib? : [küsitlus

    Index Scriptorium Estoniae

    2002-01-01

    Vastavad : Vaapo Vaher, Elo Lindsalu, Olev Remsu, Jüri Ehlvest, François Serpent, Sven Kivisildnik, Linnar Priimägi, Aino Pervik, Mati Unt, Contra, Fagira D. Morti, Aapo Ilves, Aarne Ruben, Juku-Kalle Raid

  17. 76 FR 56469 - Notice of Inventory Completion: The University of Maine, Hudson Museum, Orono, ME

    Science.gov (United States)

    2011-09-13

    ... present in their aboriginal claims area during the prehistory of what is now known as Arizona and Mexico... stories of this period in late prehistory, including not just the role of a great water serpent and a...

  18. RICIS Software Engineering 90 Symposium: Aerospace Applications and Research Directions Proceedings

    Science.gov (United States)

    1990-01-01

    Papers presented at RICIS Software Engineering Symposium are compiled. The following subject areas are covered: synthesis - integrating product and process; Serpent - a user interface management system; prototyping distributed simulation networks; and software reuse.

  19. Pop / Lauri Tikerpe

    Index Scriptorium Estoniae

    Tikerpe, Lauri

    2007-01-01

    Heliplaatidest: Laurent Garnier, Bugge Wesseltoft, Philippe Nadaud, Benjamin Rippert "Public Out Burst", Enthroned "Tetra Karcist", Bruce Springsteen with the Sessions Band "Live in Dublin", Tuxedomoon "Vapour Trails", Atreyu "Lead Sails Paper Anchor", Still Remains "The Serpent"

  20. Prise en charge des intoxications par envenimation chez les enfants ...

    African Journals Online (AJOL)

    Les signes cliniques étaient dominés par les douleurs (98%) suivies des hémorragies (73,80%) pour les morsures de serpent, la douleur pour les piqures de scorpion (100%) et les oedèmes pour les piqures d'abeilles (100%). Les cas de morsure de serpent ont été traités par le sérum antivenimeux polyvalent. Conclusion: ...

  1. Live chat alternative security protocol

    Science.gov (United States)

    Rahman, J. P. R.; Nugraha, E.; Febriany, A.

    2018-05-01

    Indonesia is one of the largest e-commerce markets in Southeast Asia, as many as 5 million people do transactions in e-commerce, therefore more and more people use live chat service to communicate with customer service. In live chat, the customer service often asks customers’ data such as, full name, address, e-mail, transaction id, which aims to verify the purchase of the product. One of the risks that will happen is sniffing which will lead to the theft of confidential information that will cause huge losses to the customer. The anticipation that will be done is build an alternative security protocol for user interaction in live chat by using a cryptographic algorithm that is useful for protecting confidential messages. Live chat requires confidentiality and data integration with encryption and hash functions. The used algorithm are Rijndael 256 bits, RSA, and SHA256. To increase the complexity, the Rijndael algorithm will be modified in the S-box and ShiftRow sections based on the shannon principle rule, the results show that all pass the Randomness test, but the modification in Shiftrow indicates a better avalanche effect. Therefore the message will be difficult to be stolen or changed.

  2. Resistance to DNA Damaging Agents Produced Invasive Phenotype of Rat Glioma Cells—Characterization of a New in Vivo Model

    Directory of Open Access Journals (Sweden)

    Sonja Stojković

    2016-06-01

    Full Text Available Chemoresistance and invasion properties are severe limitations to efficient glioma therapy. Therefore, development of glioma in vivo models that more accurately resemble the situation observed in patients emerges. Previously, we established RC6 rat glioma cell line resistant to DNA damaging agents including antiglioma approved therapies such as 3-bis(2-chloroethyl-1-nitrosourea (BCNU and temozolomide (TMZ. Herein, we evaluated the invasiveness of RC6 cells in vitro and in a new orthotopic animal model. For comparison, we used C6 cells from which RC6 cells originated. Differences in cell growth properties were assessed by real-time cell analyzer. Cells’ invasive potential in vitro was studied in fluorescently labeled gelatin and by formation of multicellular spheroids in hydrogel. For animal studies, fluorescently labeled cells were inoculated into adult male Wistar rat brains. Consecutive coronal and sagittal brain sections were analyzed 10 and 25 days post-inoculation, while rats’ behavior was recorded during three days in the open field test starting from 25th day post-inoculation. We demonstrated that development of chemoresistance induced invasive phenotype of RC6 cells with significant behavioral impediments implying usefulness of orthotopic RC6 glioma allograft in preclinical studies for the examination of new approaches to counteract both chemoresistance and invasion of glioma cells.

  3. Application of the SPH method in nodal diffusion analyses of SFR cores

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, Evgeny; Fridman, Emil [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Reactor Safety; Mikityuk, K. [Paul Scherrer Institut, Villigen (Switzerland)

    2016-07-01

    The current study investigated the potential of the SPH method, applied to correct the few-group XS produced by Serpent, to further improve the accuracy of the nodal diffusion solutions. The procedure for the generation of SPH-corrected few-group XS is presented in the paper. The performance of the SPH method was tested on a large oxide SFR core from the OECD/NEA SFR benchmark. The reference SFR core was modeled with the DYN3D and PARCS nodal diffusion codes using the SPH-corrected few-group XS generated by Serpent. The nodal diffusion results obtained with and without SPH correction were compared to the reference full-core Serpent MC solution. It was demonstrated that the application of the SPH method improves the accuracy of the nodal diffusion solutions, particularly for the rodded core state.

  4. Reptiles de zonas bajas de Yacopí (Cundinamarca, Colombia

    Directory of Open Access Journals (Sweden)

    Rafael Ángel Moreno Arias

    2006-01-01

    Full Text Available Se efectuó un inventario de reptiles que ocurren por debajo de 1.000 m en el municipio de Yacopí, Cundinamarca, Colombia. Se registraron 47 especies (26 Sauria, 19 Serpentes, un Amphisbaenia y un Testudinata, la familia y género más ricos fueron Colubridae y Anolis. La riqueza entre Sauria y  Serpentes fue diferente a la que se encuentra en el país. La fauna se agrupó según su distribución en dos tipos:  Trasandino (al oeste de la cordillera Oriental y Amplio (tanto al este como al oeste de la misma cordillera, los Saurios fueron más numerosos en el primero y las Serpentes en el segundo. Se encontró que la mayoría de reptiles se distribuye entre 0 y 2.000 m.

  5. Comment on Spracklandus Hoser, 2009 (Reptilia, Serpentes, ELAPIDAE): request for confirmation of availability of the generic name and for the nomenclatural validation of the journal in which it was published (Case 3601; BZN 70:234–237; 71:30–38; 133-135,181-182 ,252-253)

    Science.gov (United States)

    Rhodin, Anders G.J.; Kaiser, Hinrich; van Dijk, Peter Paul; Wüster, Wolfgang; O’Shea, Mark; Archer, Michael; Auliya, Mark; Boitani, Luigi; Bour, Roger; Clausnitzer, Viola; Contreras-MacBeath, Topiltzin; Crother, Brian I.; Daza, Juan M.; Driscoll, Carlos A.; Flores-Villela, Oscar; Frazier, Jack; Fritz, Uwe; Gardner, Alfred L.; Gascon, Claude; Georges, Arthur; Glaw, Frank; Grazziotin, Felipe G.; Groves, Colin P.; Haszprunar, Gerhard; Havaš, Peter; Hero, Jean-Marc; Hoffmann, Michael; Hoogmoed, Marinus S.; Horne, Brian D.; Iverson, John B.; Jäch, Manfred; Jenkins, Christopher L.; Jenkins, Richard K.B.; Kiester, A. Ross; Keogh, J. Scott; Lacher, Thomas E.; Lovich, Jeffrey E.; Luiselli, Luca; Mahler, D. Luke; Mallon, David P.; Mast, Roderic; McDiarmid, Roy W.; Measey, John; Mittermeier, Russell A.; Molur, Sanjay; Mosbrugger, Volker; Murphy, Robert W.; Naish, Darren; Niekisch, Manfred; Ota, Hidetoshi; Parham, James F.; Parr, Michael J.; Pilcher, Nicolas J.; Pine, Ronald H.; Rylands, Anthony B.; Sanderson, James G.; Savage, Jay M.; Schleip, Wulf; Scrocchi, Gustavo J.; Shaffer, H. Bradley; Smith, Eric N.; Sprackland, Robert; Stuart, Simon N.; Vetter, Holger; Vitt, Laurie J.; Waller, Tomás; Webb, Grahame; Wilson, Edward O.; Zaher, Hussam; Thomson, Scott

    2015-01-01

    In Case 3601 Raymond Hoser has asked the Commission to validate for the purposes of nomenclature the name Spracklandus Hoser, 2009, and ‘the journal in which it was published,’ issue 7 of the Australasian Journal of Herpetology (AJH). We note that the entire run of AJH has been written, edited, and published solely by Hoser. Although his requests to the Commission were presented as narrow and, in his words, ‘routine matters,’ we are convinced that they represent an important tipping-point with broad implications of major concern for zoological taxonomy and nomenclature as a whole and, by extension, the greater scientific community. Since Hoser’s actions and works have failed to follow scientific best practices (e.g. Turtle Taxonomy Working Group, 2007, 2014; Kaiser et al., 2013; Kaiser, 2014) and both the Commission’s general Recommendations and Code of Ethics in Appendix A, the global herpetological community has widely rejected his taxonomic decisions and resultant nomenclature. This has unfortunately caused a confusing dual nomenclature to develop in the herpetological community, with most boycotting or ignoring Hoser’s 700+ new names coined in the AJH, while he and a few personal followers actively promote their usage. We believe that suppression of the name Spracklandus, and all issues of AJH, is the only effective way to bring this contentious and confusing issue to resolution. The plenary power available under Article 81.1 of the Code exist specifically to allow the Commission to make rulings in individual cases that disturb stability and cause confusion, whether the works are Code-compliant or not. We maintain that it is in the interest of nomenclatural stability, not only for herpetology, but for all of zoological taxonomy, that the plenary power be invoked to declare the works in AJH unavailable, regardless of any narrow interpretation of their technical Code-compliance. We present our arguments for rejection of the validity of AJH in the following commentary. In view of the wide-reaching implications of this case for all of zoology, and reflecting the deep and broad-based community concern over these issues, our contributing authors include 70 global scientific leaders and accomplished amateurs from a wide variety of zoological disciplines.

  6. Activity evaluation from different native or irradiated with {sup 60} Co gamma rays snake venoms and their inhibitory effect on Leishmania (Leishmania) amazonensis; Avaliacao da atividade de diferentes venenos de serpentes, nativos ou irradiados, com radiacao gama de {sup 60} Co, quanto ao poder inibitorio do crescimento de Leishmania (Leishmania) amazonensis

    Energy Technology Data Exchange (ETDEWEB)

    Lourenco, Cecilia de Oliveira

    2000-07-01

    Cutaneous leishmaniasis is a disease, caused by Leishmania parasites, that occurs frequently in tropical and sub-tropical regions of the world. Skin lesions that could results in disfiguring aspect characterize it. The treatment is based on few drugs as antimony salts or pentamidine that are toxic with increasing resistance by the parasite. Alternative forms of disease treatment are in constant search, including natural components as snake venoms. Previous studies demonstrate that some components of snake venoms have an inhibitory effect against those parasites, including Leishmania species. Although snake venoms presented high toxicity, several methods have been described to detoxify most or some of their toxic components, with favorable results by the use of gamma irradiation. In this report we tested several native and irradiated snake venoms for inhibitory effect against Leishmania (Leishmania) amazonensis parasite and LLCMK{sub 2} mammalian cells, with enzymatic tests and electrophoresis. There are significant activity in Acanthophis antarcticus, Agkistrodon bilineatus, Bothrops moojeni, Bothrops jararaca, Hoplocephalus stephensi, Naja melanoleuca, Naja mossambica, Pseudechis australis, Pseudechis colletti, Pseudechis guttatus and Pseudechis porphyriacus, venom being inactive Pseudonaja textilis, Notechis ater niger, Notechis scutatus. Oxyuranus microlepidotus and Oxyuranus scutellatus venoms. After 2 KGy of {sup 60}Co irradiation most venom loses significantly their activity. Venoms with antileishmanial activity presented L-amino acid oxidase (L-AO) activity and showed common protein with a molecular weight about 60kDa in SDS-PAGE. These results indicate that L-AO activity in those venoms are probably related with antileishmanial effect. (author)

  7. An adaptive cryptographic accelerator for network storage security on dynamically reconfigurable platform

    Science.gov (United States)

    Tang, Li; Liu, Jing-Ning; Feng, Dan; Tong, Wei

    2008-12-01

    Existing security solutions in network storage environment perform poorly because cryptographic operations (encryption and decryption) implemented in software can dramatically reduce system performance. In this paper we propose a cryptographic hardware accelerator on dynamically reconfigurable platform for the security of high performance network storage system. We employ a dynamic reconfigurable platform based on a FPGA to implement a PowerPCbased embedded system, which executes cryptographic algorithms. To reduce the reconfiguration latency, we apply prefetch scheduling. Moreover, the processing elements could be dynamically configured to support different cryptographic algorithms according to the request received by the accelerator. In the experiment, we have implemented AES (Rijndael) and 3DES cryptographic algorithms in the reconfigurable accelerator. Our proposed reconfigurable cryptographic accelerator could dramatically increase the performance comparing with the traditional software-based network storage systems.

  8. Biclique cryptanalysis of the full AES

    DEFF Research Database (Denmark)

    Bogdanov, Andrey; Khovratovich, Dmitry; Rechberger, Christian

    2011-01-01

    Since Rijndael was chosen as the Advanced Encryption Standard (AES), improving upon 7-round attacks on the 128-bit key variant (out of 10 rounds) or upon 8-round attacks on the 192/256-bit key variants (out of 12/14 rounds) has been one of the most difficult challenges in the cryptanalysis of block...... ciphers for more than a decade. In this paper, we present the novel technique of block cipher cryptanalysis with bicliques, which leads to the following results: The first key recovery method for the full AES-128 with computational complexity 2126.1. The first key recovery method for the full AES-192...... with computational complexity 2189.7. The first key recovery method for the full AES-256 with computational complexity 2254.4. Key recovery methods with lower complexity for the reduced-round versions of AES not considered before, including cryptanalysis of 8-round AES-128 with complexity 2124.9. Preimage search...

  9. GUI implementation of image encryption and decryption using Open CV-Python script on secured TFTP protocol

    Science.gov (United States)

    Reddy, K. Rasool; Rao, Ch. Madhava

    2018-04-01

    Currently safety is one of the primary concerns in the transmission of images due to increasing the use of images within the industrial applications. So it's necessary to secure the image facts from unauthorized individuals. There are various strategies are investigated to secure the facts. In that encryption is certainly one of maximum distinguished method. This paper gives a sophisticated Rijndael (AES) algorithm to shield the facts from unauthorized humans. Here Exponential Key Change (EKE) concept is also introduced to exchange the key between client and server. The things are exchange in a network among client and server through a simple protocol is known as Trivial File Transfer Protocol (TFTP). This protocol is used mainly in embedded servers to transfer the data and also provide protection to the data if protection capabilities are integrated. In this paper, implementing a GUI environment for image encryption and decryption. All these experiments carried out on Linux environment the usage of Open CV-Python script.

  10. Adaptive Hardware Cryptography Engine Based on FPGA

    International Nuclear Information System (INIS)

    Afify, M.A.A.

    2011-01-01

    In the last two decades, with spread of the real time applications over public networks or communications the need for information security become more important but with very high speed for data processing, to keep up with the real time applications requirements, that is the reason for using FPGA as an implementation platform for the proposed cryptography engine. Hence in this thesis a new S-Box design has been demonstrated and implemented, there is a comparison for the simulation results for proposed S-Box simulation results with respect to different designs for S-Box in DES, Two fish and Rijndael algorithms and another comparison among proposed S-Box with different sizes. The proposed S-Box implemented with 32-bits Input data lines and compared with different designs in the encryption algorithms with the same input lines, the proposed S-Box gives implementation results for the maximum frequency 120 MHz but the DES S-Box gives 34 MHz and Rijndael gives 71 MHz, on the other hand the proposed design gives the best implementation area, hence it gives 50 Configurable logic Block CLB but DES gives 88 CLB. The proposed S-Box implemented in different sizes 64-bits, 128-bits, and 256-bits for input data lines. The implementation carried out by using UniDAq PCI card with FPGA Chip XCV 800, synthesizing carried out for all designs by using Leonardo spectrum and simulation carried out by using model sim simulator program form the FPGA advantage package. Finally the results evaluation and verifications carried out using the UniDAq FPGA PCI card with chip XCV 800. Different cases study have been implemented, data encryption, images encryption, voice encryption, and video encryption. A prototype for Remote Monitoring Control System has been implemented. Finally the proposed design for S-Box has a significant achievement in maximum frequency, implementation area, and encryption strength.

  11. Luulelaat vaimuväljadel / Priidu Beier

    Index Scriptorium Estoniae

    Beier, Priidu, 1957-

    1997-01-01

    Arvustus: Rahman, Jan. Vasõst vask; Serpent, François. Ka Jumal on inimene; Märka, Veiko. Tühja aju korinad; Rüütle, Indrek. Lahkumine Puhjast (kõik Eesti Kostabi Seltsi Kaasaegse Kirjanduse Keskuse väljaanded, 1997)

  12. Fulltext PDF

    Indian Academy of Sciences (India)

    Srimath

    , almost covering the stem. Stamens are many and fused to form a structure that resembles a serpent's hood. Fruits are cannon-ball sized with brown hard shell emitting unpleasant odour on ripening. Seeds are embedded in foul-smelling pulp.

  13. Anurans Collected in West Malaysia

    DEFF Research Database (Denmark)

    Cedhagen, Tomas

    1997-01-01

    Distributional records and natural history noles are given for anurans collected in West Malaysia 1976. Rano baramica was observed when it was caught by an Ahaetulfa nasula (Serpentes: Colubridae). Rhacophorus leucomystax, Limnonectes limnociulris and Microhyla heymonsi were all found al night on...

  14. M-X Environmental Technical Report. Environmental Characteristics of Alternative Designated Deployment Areas, Native Americans (Nevada/Utah).

    Science.gov (United States)

    1980-12-22

    spawning runs of several fish species provided a storable protein food source for local groups. Bison. Available evidence indicates that this large herd...to contain serpents resembling huge dinosaurs or amphibian reptiles. Sitings of such a monster in the vicinity of Walker Lake by non-Indians have

  15. Great Lakes and St. Lawrence Seaway Navigation Season Extension. Volume 4. Appendixes D - F

    Science.gov (United States)

    1979-08-01

    River) Montreal River Serpent River Ontonagon McCurry Lake Outlet Maitland River Douglas Point NOTE: Except for connecting channels, problem areas...loca- ian and white National ted _ cemetery ...... Reister 20 MU 27 George Campau Muskegon Not on the none trading post, National ...... 1833-1835

  16. Chimerism in health, transplantation and autoimmunity

    NARCIS (Netherlands)

    Koopmans, Marije; Kremer Hovinga, Idske Cornelia Lydia

    2009-01-01

    The term “chimerism” originates from Greek mythology and refers to the creature Chimaera, whose body was in front a lion, the back a serpent and the midsection a goat. In medicine, the term chimerism refers to an individual, organ or part consisting of tissues of diverse genetic constitution.

  17. 77 FR 4810 - Pesticide Products; Receipt of Applications To Register New Uses

    Science.gov (United States)

    2012-01-31

    ..., but are not limited to: Crop production (NAICS code 111). Animal production (NAICS code 112). Food..., chinese onion, daylily bulb, fritillaria bulb, great-headed, garlic, lily bulb, pearl onion, potato onion, serpent garlic, shallot, green onion, beltsville bunching, onion, Chinese chive, fresh leaves, fresh chive...

  18. 78 FR 14539 - Notice of Receipt of Pesticide Products; Registration Applications To Register New Uses

    Science.gov (United States)

    2013-03-06

    ... include: Crop production (NAICS code 111). Animal production (NAICS code 112). Food manufacturing (NAICS...), fritillaria (bulb), garlic (bulbs of common, great-headed, serpent), lily (bulb), onion (bulbs of common..., fritillaria (leaves), kurrat, leek, wild leek, lady's leek, Beltsville bunching onion, fresh onion, green...

  19. Kõige olulisemate Prantsuse kirjandusauhindade väljakuulutamine langeb novembri algusele / Lauri Eesmaa

    Index Scriptorium Estoniae

    Eesmaa, Lauri

    2004-01-01

    Académie Franȧise'i romaanipreemia sai Bernard du Boucheron romaani "Court serpent" ("Lühike madu") eest. Goncourt'i preemia sai Laurent Gaudé romaani "La soleil des Scorta" ("Scortade päike" eest). Redaunot' preemia määrati postuumselt Irene Némirovsky romaanile "Suite Franȧise"

  20. Ethical, psychosocial and anthropological

    African Journals Online (AJOL)

    “If our dearly beloved is dead, we will not bury him, but will eat him, for it will ... body of my son, for I am feeling truly grief-stricken and would like to keep it. ..... by decay of a chief's corpse resulted in the appearance of a large sea- serpent.[22].

  1. ORGANOMETALLIC IRON(II) COMPLEXES CONTAINING P-SUBSTITUTED ACETOPHENONE-ARYLHYDRAZONE LIGANDS

    OpenAIRE

    Manzur, Carolina; Millán, Lorena; Figueroa, Walter; Hamon, Jean-René; Mata, Jose A.; Carrillo, David

    2002-01-01

    A series of twelve new organometallic acetophenone-hydrazone complexes of general formula [(h 5-Cp)Fe(h 6-o-RC6H4)-NHN=CMe-C6H4-p-R’]+PF6- (Cp= C5H5; R,R’=H,Me, [5]+PF6-; H,MeO, [6]+PF6-; H,NMe2, [7]+PF6-; Me,Me, [8]+PF6-; Me,MeO, [9]+PF6-; Me,NMe2, [10]+PF6-; MeO,Me, [11]+PF6-; MeO,MeO, [12]+PF6-; MeO,NMe2, [13]+PF6-; Cl,Me, [14]+PF6-; Cl,MeO, [15]+PF6-; Cl,NMe2, [16]+PF6-) has been prepared by reaction between their corresponding organometallic hydrazine precursors [(h 5-Cp)Fe(h 6-o-RC6H4)-...

  2. Two New Secreted Proteases Generate a Casein-Derived Antimicrobial Peptide in Bacillus cereus Food Born Isolate Leading to Bacterial Competition in Milk

    Directory of Open Access Journals (Sweden)

    Awatef Ouertani

    2018-06-01

    Full Text Available Milk and dairy products harbor a wide variety of bacterial species that compete for both limited resources and space. Under these competitive conditions, bacteria develop specialized mechanisms to protect themselves during niche colonization and nutrient acquisition processes. The bacterial antagonism mechanisms include the production of antimicrobial agents or molecules that facilitate competitor dispersal. In the present work, a bacterial strain designated RC6 was isolated from Ricotta and identified as Bacillus cereus. It generates antimicrobial peptide (AMP when grown in the presence of casein. The AMP was active against several species of Bacillus and Listeria monocytogenes. MALDI-TOF analysis of the RP-HPLC purified fractions and amino acid sequencing revealed a molecular mass of 751 Da comprised of a 6-residue sequence, YPVEPF. BLAST analysis showed that the AMP corresponds to the fractions 114–119 of bovine β-casein and represents the product of a specific proteolysis. Analysis of the purified proteolytic fractions from the B. cereus RC6 culture supernatant indicated that the presence of at least two different endoproteases is crucial for the generation of the AMP. Indeed, we were able to identify two new candidate endoproteases by means of genome sequencing and functional assignment using a 3D structural model and molecular docking of misannotated hypothetical proteins. In this light, the capacity of B. cereus RC6 to generate antimicrobial peptides from casein, through the production of extracellular enzymes, presents a new model of antagonistic competition leading to niche colonization. Hence, as a dairy product contaminant, this strategy may enable proteolytic B. cereus RC6 niche specialization in milk matrices.

  3. Poesia em Revista: Oroboro

    Directory of Open Access Journals (Sweden)

    Helena Alves Gouveia

    2008-10-01

    Full Text Available http://dx.doi.org/10.5007/1984-784x.2008v8n12p38 A serpente que engole a si mesma é uma figura curiosa do simbolismo de um processo de contínua transformação, de um movimento circular incessante, rumo à infinitude, sem traços de fim ou começo. Oroboro é um nome de origem grega que remete a esta serpente que se morde e penetra em si mesma ao engolir o próprio rabo. Mas também é o nome da revista de cultura editada em Curitiba pelos artistas-editores Ricardo Corona e Eliana Borges.

  4. Digenetic trematodes infection in a Bothrops moojeni (Viperidae population from a fauna rescue in Porto Primavera, São Paulo State

    Directory of Open Access Journals (Sweden)

    Barrella T.H.

    2003-01-01

    Full Text Available No presente estudo é descrita a infecção por trematódeos digenéticos parasitas da cavidade oral e esôfago em uma população de serpentes Bothrops moojeni provenientes de resgate de fauna em Porto Primavera, Estado de São Paulo. Foi observada prevalência de infecção de 68%. O grau de infecção (número de trematódeos por serpente variou de 2 a 51 helmintos. Os trematódeos encontrados foram Ophisthogonimus spp. e Sticholecitha serpentis. A alta prevalência de infecção foi associada com a drástica alteração ambiental e o estresse multi-fatorial aos quais os animais foram submetidos, que poderiam ter favorecido o ciclo dos parasitas.

  5. [Rod of Asclepius. Symbol of medicine].

    Science.gov (United States)

    Young, Pablo; Finn, Bárbara C; Bruetman, Julio E; Cesaro Gelos, Jorge; Trimarchi, Hernán

    2013-09-01

    Symbolism is one of the most archaic forms of human thoughts. Symbol derives from the Latin word symbolum, and the latter from the Greek symbolon or symballo, which means "I coincide, I make matches". The Medicine symbol represents a whole series of historical and ethical values. Asclepius Rod with one serpent entwined, has traditionally been the symbol of scientific medicine. In a misconception that has lasted 500 years, the Caduceus of Hermes, entwined by two serpents and with two wings, has been considered the symbol of Medicine. However, the Caduceus is the current symbol of Commerce. Asclepius Rod and the Caduceus of Hermes represent two professions, Medicine and Commerce that, in ethical practice, should not be mixed. Physicians should be aware of their real emblem, its historical origin and meaning.

  6. Expedition 357 Preliminary Report: Atlantis Massif Serpentinization and Life

    OpenAIRE

    Früh-Green, GL; Orcutt, BN; Green, S; Cotterill, C; McCaig, AM; Expedition 357 Scientists,

    2016-01-01

    International Ocean Discovery Program (IODP) Expedition 357 successfully cored an east–west transect across the southern wall of Atlantis Massif on the western flank of the Mid-Atlantic Ridge to study the links between serpentinization processes and microbial activity in the shallow subsurface of highly altered ultramafic and mafic sequences that have been uplifted to the seafloor along a major detachment fault zone. The primary goals of this expedition were to (1) examine the role of serpent...

  7. Transmutation of Americium in Fast Neutron Facilities

    OpenAIRE

    Zhang, Youpeng

    2011-01-01

    In this thesis, the feasibility to use a medium sized sodium cooled fast reactor fully loaded with MOX fuel for efficient transmutation of americium is investigated by simulating the safety performance of a BN600-type fast reactor loaded with different fractions of americium in the fuel, using the safety parameters obtained with the SERPENT Monte Carlo code. The focus is on americium mainly due to its long-term contribution to the radiotoxicity of spent nuclear fuel and its deterioration on c...

  8. Optimization of the fuel assembly for the Canadian Supercritical Water-cooled Reactor (SCWR)

    Energy Technology Data Exchange (ETDEWEB)

    French, C.; Bonin, H.; Chan, P., E-mail: Corey.French@rmc.ca [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, Ontario (Canada)

    2013-07-01

    A parametric optimization of the Canadian Supercritical Water-cooled Reactor (SCWR) lattice geometry and fresh fuel content is performed in this work. With the potential to improve core physics and performance, significant gains to operating and safety margins could be achieved through slight progressions. The fuel performance codes WIMS-AECL and SERPENT are used to calculate performance factors, and use them as inputs to an optimization algorithm. (author)

  9. Vikergallup : eesti kirjandus 2000 : [vastused Vikerkaare küsimustele

    Index Scriptorium Estoniae

    2001-01-01

    Aut.: Epp Annus, Andres Aule, Veiko Belials, Jan Kaus, Andrus Kivirähk, Leo Luks, Hedda Maurer, Anneli Mihkelev, Marko Mägi, Aare Pilv, Jürgen Rooste, Aarne Ruben, Mihkel Samarüütel, François Serpent, Ivar Sild, Karl Martin Sinijärv, Jaak Urmet. 2000. a. parimaks uudisraamatuks tunnistati Andrus Kivirähu "Rehepapp ehk November" ja parimaks esikraamatuks Wimbergi [Jaak Urmet] "Maaaraamat"

  10. Restauratsioon / Mart Velsker

    Index Scriptorium Estoniae

    Velsker, Mart, 1966-

    1998-01-01

    Arvustus: Üheksavägine. Tartu : Erakkond, 1997.Märka, Veiko. Tühja aju korinad; Rahman, Jan. Vasõst vask; Rüütle, Indrek. Lahkumine Puhjast; Serpent, Franȯis. Ka jumal on inimene (kõik EK$i Kaasaegse Kirjanduse Keskuse väljaanded, Tartu, 1997). Vastukaja: Pilv, Aare. Vastuseks Mart Velskri 'Restauratsioonile' // Vikerkaar (1998) nr. 4-5, lk. 185-186

  11. Application of CHD1 Gene and EE0.6 Sequences to Identify Sexes of Several Protected Bird Species in Taiwan

    Directory of Open Access Journals (Sweden)

    E.-C. Lin

    2011-06-01

    Full Text Available Many bird species, for example: Crested Serpent Eagle (Spilornis cheela hoya, Collared Scops (Owl Otus bakkamoena, Tawny Fish Owl (Ketupa flavipes, Crested Goshawk (Accipiter trivirgatus, and Grass Owl (Tyto longimembris... etc, are monomorphic, which is difficult to identify their sex simply by their outward appearance. Especially for those monomorphic endangered species, finding an effective tool to identify their sex beside outward appearance is needed for further captive breeding programs or other conservation plans. In this study, we collected samples of Black Swan (Cygmus atratus and Nicobar Pigeon (Caloenas nicobarica, two aviaries introduced monomorphic species served as control group, and Crested Serpent Eagle, Collared Scops Owl, Tawny Fish Owl, Crested Goshawk, and Grass Owl, five protected monomorphic species in Taiwan. We used sex-specific primers of avian CHD1 (chromo-helicase-DNA-binding gene and EE0.6 (EcoRI 0.6-kb fragment sequences to identify the sex of these birds. The results showed that CHD1 gene primers could be used to correctly identify the sex of Black Swans, Nicobar Pigeons and Crested Serpent Eagles, but it could not be used to correctly identify sex in Collared Scops Owls, Tawny Fish Owls, and Crested Goshawks. In the sex identification using EE0.6 sequence fragment, A, C, D and E primer sets could be used for sexing Black Swans; A, B, C, and D primer sets could be used for sexing Crested Serpent Eagles; and E primer set could be used for sexing Nicobar Pigeons and the two owl species. Correct determination of sex is the first step if a captive breeding measure is required. We have demonstrated that several of the existing primer sets can be used for sex determination of several captive breeding and indigenous bird species.

  12. Towards a reconstruction of the contributions of the Argentine experience to the development of International Human Rights Law: the voices of Claudia Fontes and Paula Bombara

    OpenAIRE

    Estefanía Giaccone; Viviana Kühne; Agustina Vázquez

    2017-01-01

    In the present dissertation, we intend to relate and contrast the representations that emerge from legal and political-institutional discourses on the crime of forced disappearance of persons in the Argentinian historical experience. In this sense, we will analyze the representations of the crime of forced disappearance of persons in two artistic works: The Reconstruction of Pablo Miguez Portrait, Claudia Fontes’ sculpture, and The Sea and the Serpent, a novel by Paula Bombara, in order to re...

  13. Species composition of the Amphibians and Reptiles in the Natura 2000 Site „Oranovski Prolom - Leshko”, Bulgaria

    Directory of Open Access Journals (Sweden)

    NEVENА MALAKOVA

    2018-04-01

    Full Text Available The Natura 2000 site „Oranovski Prolom - Leshko” (BG0001022 was studied in Jul 2013-Dec 2017 in order to supplement and summarize the information about the diversity and distribution of the herpetofauna. Two new species of amphibians (Caudata and 8 new species of reptiles (4 Sauria and 4 Serpentes have been registered. Thus the total number of the representatives of herpetofauna is 29 (10 amphibians and 19 reptiles.

  14. Occurrence of Microcerella halli (Engel (Diptera, Sarcophagidae in snake carrion in southeastern Brazil Ocorrência de Microcerella halli (Engel (Diptera, Sarcophagidae em uma Carcaça de Cobra no Sudeste Brasileiro

    Directory of Open Access Journals (Sweden)

    Thiago de C. Moretti

    2009-06-01

    Full Text Available The occurrence of 27 second-instar larvae of the flesh fly Microcerella halli (Engel, 1931 (Diptera, Sarcophagidae in a carcass of a snake usually called as Urutu, Bothrops alternatus (Duméril, Bibron & Duméril, 1854 (Serpentes, Viperidae, Crotalinae is reported. The snake was kept in captivity in a snake farm in Morungaba, São Paulo state, Brazil. Descriptions of reptile carcass colonization by insects and general biological data of this flesh fly are scarce and this necrophagic behavior is described for the first time in literature.A ocorrência de 27 larvas de segundo estádio do sarcofagídeo Microcerella halli (Engel, 1931 (Diptera, Sarcophagidae em uma carcaça de urutu Bothrops alternatus (Duméril, Bibron & Duméril, 1854 (Serpentes, Viperidae, Crotalinae é relatada. A cobra era mantida em cativeiro em um serpentário no município de Morungaba, estado de São Paulo, Brasil. Descrições de colonização de carcaças de répteis por insetos e dados gerais da biologia deste sarcofagídeo são escassos, e este comportamento necrófago é descrito pela primeira vez na literatura.

  15. Methods and Models for the Coupled Neutronics and Thermal-Hydraulics Analysis of the CROCUS Reactor at EFPL

    Directory of Open Access Journals (Sweden)

    A. Rais

    2015-01-01

    Full Text Available In order to analyze the steady state and transient behavior of the CROCUS reactor, several methods and models need to be developed in the areas of reactor physics, thermal-hydraulics, and multiphysics coupling. The long-term objectives of this project are to work towards the development of a modern method for the safety analysis of research reactors and to update the Final Safety Analysis Report of the CROCUS reactor. A first part of the paper deals with generation of a core simulator nuclear data library for the CROCUS reactor using the Serpent 2 Monte Carlo code and also with reactor core modeling using the PARCS code. PARCS eigenvalue, radial power distribution, and control rod reactivity worth results were benchmarked against Serpent 2 full-core model results. Using the Serpent 2 model as reference, PARCS eigenvalue predictions were within 240 pcm, radial power was within 3% in the central region of the core, and control rod reactivity worth was within 2%. A second part reviews the current methodology used for the safety analysis of the CROCUS reactor and presents the envisioned approach for the multiphysics modeling of the reactor.

  16. Computation of a Canadian SCWR unit cell with deterministic and Monte Carlo codes

    International Nuclear Information System (INIS)

    Harrisson, G.; Marleau, G.

    2012-01-01

    The Canadian SCWR has the potential to achieve the goals that the generation IV nuclear reactors must meet. As part of the optimization process for this design concept, lattice cell calculations are routinely performed using deterministic codes. In this study, the first step (self-shielding treatment) of the computation scheme developed with the deterministic code DRAGON for the Canadian SCWR has been validated. Some options available in the module responsible for the resonance self-shielding calculation in DRAGON 3.06 and different microscopic cross section libraries based on the ENDF/B-VII.0 evaluated nuclear data file have been tested and compared to a reference calculation performed with the Monte Carlo code SERPENT under the same conditions. Compared to SERPENT, DRAGON underestimates the infinite multiplication factor in all cases. In general, the original Stammler model with the Livolant-Jeanpierre approximations are the most appropriate self-shielding options to use in this case of study. In addition, the 89 groups WIMS-AECL library for slight enriched uranium and the 172 groups WLUP library for a mixture of plutonium and thorium give the most consistent results with those of SERPENT. (authors)

  17. Assessing reactor physics codes capabilities to simulate fast reactors on the example of the BN-600 benchmark

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Vladimir [Scientific and Engineering Centre for Nuclear and Radiation Safety (SES NRS), Moscow (Russian Federation); Bousquet, Jeremy [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Garching (Germany)

    2016-11-15

    This work aims to assess the capabilities of reactor physics codes (initially validated for thermal reactors) to simulate fast sodium cooled reactors. The BFS-62-3A critical experiment from the BN-600 Hybrid Core Benchmark Analyses was chosen for the investigation. Monte-Carlo codes (KENO from SCALE and SERPENT 2.1.23) and the deterministic diffusion code DYN3D-MG are applied to calculate the neutronic parameters. It was found that the multiplication factor and reactivity effects calculated by KENO and SERPENT using the ENDF/B-VII.0 continuous energy library are in a good agreement with each other and with the measured benchmark values. Few-groups macroscopic cross sections, required for DYN3D-MG, were prepared in applying different methods implemented in SCALE and SERPENT. The DYN3D-MG results of a simplified benchmark show reasonable agreement with results from Monte-Carlo calculations and measured values. The former results are used to justify DYN3D-MG implementation for sodium cooled fast reactors coupled deterministic analysis.

  18. Syntheses, spectroscopic characterization, crystal structure and natural rubber vulcanization activity of new disulfides derived from sulfonyldithiocarbimates

    Science.gov (United States)

    Alves, Leandro de Carvalho; Rubinger, Mayura Marques Magalhães; Tavares, Eder do Couto; Janczak, Jan; Pacheco, Elen Beatriz Acordi Vasques; Visconte, Leila Lea Yuan; Oliveira, Marcelo Ribeiro Leite

    2013-09-01

    The compounds (Bu4N)2[(4-RC6H4SO2NCS2)2] [Bu4N = tetrabutylammonium cation; R = H (1), F (2), Cl (3) and Br (4)] and (Ph4P)2[(4-RC6H4SO2NCS2)2]ṡH2O [Ph4P = tetraphenylphosphonium cation and R = I (5)] were synthesized by the reaction of the potassium dithiocarbimates (4-RC6H4SO2NCS2K2ṡ2H2O) with I2 and Bu4NBr or Ph4PCl. The IR data were consistent with the formation of the dithiocarbimatodisulfides anions. The NMR spectra showed the expected signals for the cations and anions in a 2:1 proportion. The structures of compounds 1-5 were determined by the single crystal X-ray diffraction. The compounds 2, 3 and 4 are isostructural and crystallise in the centrosymmetric space group C2/c of the monoclinic system. Compound 1 crystallises in the monoclinic system in the space group of P21/n and the compound 5 crystallises in the centrosymmetric space group P-1 of the triclinic system. The complex anions of compounds 2, 3 and 4 exhibit similar conformations having twofold symmetry, while in 1 and 5 the anions exhibit C1 symmetry. The activity of the new compounds in the vulcanization of the natural rubber was evaluated and compared to the commercial accelerators ZDMC, TBBS and TMTD. These studies confirm that the sulfonyldithiocarbimato disulfides anions are new vulcanization accelerators, being slower than the commercial accelerators, but producing a greater degree of crosslinking, and scorch time values compatible with good processing safety for industrial applications. The mechanical properties, stress and tear resistances were determined and compared to those obtained with the commercial accelerators.

  19. Uncertainties in the dosemeter calibration used for dosimetry in mammography; Incertezas na calibração de dosímetros utilizados para dosimetria em mamografia

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, Vivian C.R.N.; Evangelista, Claudete R.; Silva, Teógenes A. da, E-mail: vcrnb@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    This study aims to detail the sources of uncertainties and to estimate the combined standard uncertainties associated with the calibration procedure of dosimeters to be used in the dosimetry of X-ray bundles in mammography. A RADCAL ionization chamber, model RC6-M, and the semiconductor dosimeters UNFORS Xi and RADCAL Digitizer AGDM Accul-Gold were used. The calibration coefficients in terms of air kerma and uncertainties were obtained for the reference radiations of the W-Mo target-filter combinations. (author)

  20. Ecology of a snake assemblage in the Atlantic Forest of southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Paulo A. Hartmann

    2009-01-01

    Full Text Available The main objective of this study was to examine the natural history and the ecology of the species that constitute a snake assemblage in the Atlantic Rainforest, at Núcleo Picinguaba, Parque Estadual da Serra do Mar, located on the northern coast of the state of São Paulo, southeastern Brazil. The main aspects studied were: richness, relative abundance, daily and seasonal activity, and substrate use. We also provide additional information on natural history of the snakes. A total of 282 snakes, distributed over 24 species, belonging to 16 genera and four families, has been found within the area of the Núcleo Picinguaba. Species sampled more frequently were Bothrops jararaca and B. jararacussu. The methods that yielded the best results were time constrained search and opportunistic encounters. Among the abiotic factors analyzed, minimum temperature, followed by the mean temperature and the rainfall are apparently the most important in determining snake abundance. Most species presented a diet concentrated on one prey category or restricted to a few kinds of food items. The large number of species that feed on frogs points out the importance of this kind of prey as an important food resource for snakes in the Atlantic Rainforest. Our results indicate that the structure of the Picinguaba snake assemblage reflects mainly the phylogenetic constraints of each of its lineages.O principal objetivo deste estudo foi obter informações sobre a história natural e a ecologia das espécies que compõem uma taxocenoses de serpentes da Mata Atlântica, no Núcleo Picinguaba do Parque Estadual da Serra do Mar, localizado no litoral norte do estado no Estado de São Paulo, sudeste do Brasil. Os principais aspectos estudados foram: riqueza, abundância relativa de espécies, padrões de atividade diária e sazonal, utilização do ambiente e dieta. Um total de 282 serpentes, distribuídas em 24 espécies, pertencentes a 16 gêneros e quatro famílias, foi

  1. Preliminary Analysis of the Transient Reactor Test Facility (TREAT) with PROTEUS

    Energy Technology Data Exchange (ETDEWEB)

    Connaway, H. M. [Argonne National Lab. (ANL), Argonne, IL (United States); Lee, C. H. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-11-30

    The neutron transport code PROTEUS has been used to perform preliminary simulations of the Transient Reactor Test Facility (TREAT). TREAT is an experimental reactor designed for the testing of nuclear fuels and other materials under transient conditions. It operated from 1959 to 1994, when it was placed on non-operational standby. The restart of TREAT to support the U.S. Department of Energy’s resumption of transient testing is currently underway. Both single assembly and assembly-homogenized full core models have been evaluated. Simulations were performed using a historic set of WIMS-ANL-generated cross-sections as well as a new set of Serpent-generated cross-sections. To support this work, further analyses were also performed using additional codes in order to investigate particular aspects of TREAT modeling. DIF3D and the Monte-Carlo codes MCNP and Serpent were utilized in these studies. MCNP and Serpent were used to evaluate the effect of geometry homogenization on the simulation results and to support code-to-code comparisons. New meshes for the PROTEUS simulations were created using the CUBIT toolkit, with additional meshes generated via conversion of selected DIF3D models to support code-to-code verifications. All current analyses have focused on code-to-code verifications, with additional verification and validation studies planned. The analysis of TREAT with PROTEUS-SN is an ongoing project. This report documents the studies that have been performed thus far, and highlights key challenges to address in future work.

  2. Coupling of system thermal–hydraulics and Monte-Carlo code: Convergence criteria and quantification of correlation between statistical uncertainty and coupled error

    International Nuclear Information System (INIS)

    Wu, Xu; Kozlowski, Tomasz

    2015-01-01

    Highlights: • Coupling of Monte Carlo code Serpent and thermal–hydraulics code RELAP5. • A convergence criterion is developed based on the statistical uncertainty of power. • Correlation between MC statistical uncertainty and coupled error is quantified. • Both UO 2 and MOX single assembly models are used in the coupled simulation. • Validation of coupling results with a multi-group transport code DeCART. - Abstract: Coupled multi-physics approach plays an important role in improving computational accuracy. Compared with deterministic neutronics codes, Monte Carlo codes have the advantage of a higher resolution level. In the present paper, a three-dimensional continuous-energy Monte Carlo reactor physics burnup calculation code, Serpent, is coupled with a thermal–hydraulics safety analysis code, RELAP5. The coupled Serpent/RELAP5 code capability is demonstrated by the improved axial power distribution of UO 2 and MOX single assembly models, based on the OECD-NEA/NRC PWR MOX/UO 2 Core Transient Benchmark. Comparisons of calculation results using the coupled code with those from the deterministic methods, specifically heterogeneous multi-group transport code DeCART, show that the coupling produces more precise results. A new convergence criterion for the coupled simulation is developed based on the statistical uncertainty in power distribution in the Monte Carlo code, rather than ad-hoc criteria used in previous research. The new convergence criterion is shown to be more rigorous, equally convenient to use but requiring a few more coupling steps to converge. Finally, the influence of Monte Carlo statistical uncertainty on the coupled error of power and thermal–hydraulics parameters is quantified. The results are presented such that they can be used to find the statistical uncertainty to use in Monte Carlo in order to achieve a desired precision in coupled simulation

  3. Determinação de hemogregarina em Boa constrictor constrictor mantidos em cativeiro

    Directory of Open Access Journals (Sweden)

    Monique A. Luz

    2012-08-01

    Full Text Available O presente estudo teve como objetivo determinar a presença de hemogregarina em boídeos mantidos em cativeiro no Estado do Pará, bem como, relacionar a hemoparasitose com pre-disposição sexual, alterações clínicas e hematológicas e a presença de ectoparasitos. Esta pesquisa teve autorização do Sistema de Autorização e Informação em Biodiversidade do Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis para ser realizado. Utilizaram-se 19 serpentes da família Boidae mantidas em cativeiro, pertencentes ao "Museu Paraense Emilio Goeldi" (Belém/PA e "Sítio Xerimbabo" (Santo Antônio do Tauá/PA. A pesquisa de hemogregarina foi realizada em esfregaços sanguíneos examinados no aumento de 400x, enquanto que a parasitemia foi determinada contando- se 550 hemácias em aumento de 1000x. Do total de animais estudados (n=19, nove encontraram-se parasitados (47,36%, não havendo correlação entre presença de hemogregarina, pré-disposição sexual, alterações clínicas e hematológicas nas serpentes hospedeiras. A correlação da hemoparasitose foi detectada apenas quanto à presença de ectoparasitas nas serpentes, no entanto, estudos adicionais são necessários para verificar a prevalência de hemogregarinas em animais mantidos em cativeiro no Estado do Pará, visto que, existe grande lacuna de dados na literatura veterinária especializada no que diz respeito à fauna da região amazônica.

  4. Dragones, serpientes y cocodrilos infernales en la comedia de santos

    OpenAIRE

    Gonzalez Fernandez , Luis

    2009-01-01

    International audience; Se examinan en este artículo algunos casos en los que aparecen dragones, serpientes y cocodrilos vinculados al personaje teatral del demonio en la comedia de santos. El corpus es mayormente calderoniano.; Parcours retraçant dans la comedia de santos (pièces hagiographiques) la présence de monstres tels que les dragons, les serpents et les crocodiles là où il y a une relation spécifique avec le diable. Le corpus examiné porte essentiellement sur les oeuvres de Pedro Cal...

  5. Analysis of results of AZTRAN and AZKIND codes for a BWR; Analisis de resultados de los codigos AZTRAN y AZKIND para un BWR

    Energy Technology Data Exchange (ETDEWEB)

    Bastida O, G. E.; Vallejo Q, J. A.; Galicia A, J.; Francois L, J. L. [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Paseo Cuauhnahuac 8532, 62550 Jiutepec, Morelos (Mexico); Xolocostli M, J. V.; Rodriguez H, A.; Gomez T, A. M., E-mail: gbo729@yahoo.com.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2016-09-15

    This paper presents an analysis of results obtained from simulations performed with the neutron transport code AZTRAN and the kinetic code of neutron diffusion AZKIND, based on comparisons with models corresponding to a typical BWR, in order to verify the behavior and reliability of the values obtained with said code for its current development. For this, simulations of different geometries were made using validated nuclear codes, such as CASMO, MCNP5 and Serpent. The results obtained are considered adequate since they are comparable with those obtained and reported with other codes, based mainly on the neutron multiplication factor and the power distribution of the same. (Author)

  6. Spatial and spectral effects in subcritical system pulsed experiments

    International Nuclear Information System (INIS)

    Dulla, S.; Nervo, M.; Ravetto, P.; Carta, M.

    2013-01-01

    Accurate neutronic models are needed for the interpretation of pulsed experiments in subcritical systems. In this work, the extent of spatial and spectral effects in the pulse propagation phenomena is investigated and the analysis is applied to the GUINEVERE experiment. The multigroup cross section data is generated by the Monte Carlo SERPENT code and the neutronic evolution following the source pulse is simulated by a kinetic diffusion code. The results presented show that important spatial and spectral aspects need to be properly accounted for and that a detailed energy approach may be needed to adequately capture the physical features of the system to the pulse injection. (authors)

  7. Analysis of results of AZTRAN and AZKIND codes for a BWR

    International Nuclear Information System (INIS)

    Bastida O, G. E.; Vallejo Q, J. A.; Galicia A, J.; Francois L, J. L.; Xolocostli M, J. V.; Rodriguez H, A.; Gomez T, A. M.

    2016-09-01

    This paper presents an analysis of results obtained from simulations performed with the neutron transport code AZTRAN and the kinetic code of neutron diffusion AZKIND, based on comparisons with models corresponding to a typical BWR, in order to verify the behavior and reliability of the values obtained with said code for its current development. For this, simulations of different geometries were made using validated nuclear codes, such as CASMO, MCNP5 and Serpent. The results obtained are considered adequate since they are comparable with those obtained and reported with other codes, based mainly on the neutron multiplication factor and the power distribution of the same. (Author)

  8. Vikergallup : eesti kirjandus 2001 : [vastused Vikerkaare küsitlusele

    Index Scriptorium Estoniae

    2002-01-01

    Aut.: Vahur Afanasjev, Veiko Belials, Piret Jaaks, Jan Kaus, Janek Kraavi, Priit Kruus, Leo Luks, Ilona Martson, Hedda Maurer, Anneli Mihkelev, Jürgen Rooste, Aarne Ruben, Mihkel Samarüütel, François Serpent, Ivar Sild, Karl Martin Sinijärv, Lauri Sommer, Jaak Urmet, Berk Vaher. 2001. a. parima uudisraamatu tiitlit jagasid Mehis Heinsaare "Härra Pauli kroonikad", Jan Kausi "Maailm ja mõni" ning Ene Mihkelsoni "Ahasveeruse uni"; parimaks esikraamatuks valiti Mehis Heinsaare "Vanameeste näppaja"

  9. Vikergallup : eesti kirjandus 1999 : [ajakirja Vikerkaar küsitlus

    Index Scriptorium Estoniae

    2000-01-01

    Aut.: Epp Annus, Tõnu Kaalep, Jan Kaus, Vilja Kiisler, Andrus Kivirähk, Valle-Sten Maiste, Hedda Maurer, Anneli Mihkelev, Mihkel Nummert, Aarne Ruben, Olavi Ruitlane, Mihkel Samarüütel, Franȯis Serpent, Karl Martin Sinijärv, Kadri Tüür, Jaak Urmet, Berk Vaher, Andreas Walden, Mart Velsker. 1999. a. parimaks uudisraamatuks tunnistati küsitluse põhjal Jaan Isotamme "Ma olin Johnny B" (Ilmamaa) ja parimaks esikteoseks Kalju Kruusa "Meeleolu" (Erakkond)

  10. Neutron analysis of the fuel of high temperature nuclear reactors; Analisis neutronico del combustible de reactores nucleares de alta temperatura

    Energy Technology Data Exchange (ETDEWEB)

    Bastida O, G. E.; Francois L, J. L., E-mail: gbo729@yahoo.com.mx [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Paseo Cuauhnahuac 8532, 62550 Jiutepec, Morelos (Mexico)

    2014-10-15

    In this work a neutron analysis of the fuel of some high temperature nuclear reactors is presented, studying its main features, besides some alternatives of compound fuel by uranium and plutonium, and of coolant: sodium and helium. For this study was necessary the use of a code able to carry out a reliable calculation of the main parameters of the fuel. The use of the Monte Carlo method was convenient to simulate the neutrons transport in the reactor core, which is the base of the Serpent code, with which the calculations will be made for the analysis. (Author)

  11. Monte Carlo applications to core-following of the National Research Universal reactor (NRU)

    International Nuclear Information System (INIS)

    Nguyen, T.S.; Wang, X.; Leung, T.

    2014-01-01

    Reactor code TRIAD, relying on a two-group neutron diffusion model, is currently used for core-following of NRU - to track reactor assembly locations and burnups. The Monte Carlo (MCNP or SERPENT) full-reactor models of NRU can be used to provide the core power distribution for calculating fuel burnups, with WIMS-AECL providing fuel depletion calculations. The MCNP/WIMS core-following results were in good agreement with the measured data, within the expected biases. The Monte Carlo methods, still very time-consuming, need to be able to run faster before they can replace TRIAD for timely support of NRU operations. (author)

  12. Mídia e educação: Os ofídios por trás das câmeras – répteis ou monstros?

    Directory of Open Access Journals (Sweden)

    Beatriz Nunes Cosendey

    2016-11-01

    Full Text Available Routinely placed in the hot seat by social media, the snakes are animals surrounded by stories and mysteries. Aiming to investigate how the snakes are seen culturally, commercial movies about the subject were analyzed, having some scenes selected and edited to compose a short movie (also utilized as teaching material. Through a questionnaire, followed by the short movie exhibition and a debate, the previous knowledge about snakes of Pedagogy undergraduates were assessed. The movie analysis showed that they generally exaggerate reality, merging science and fiction. After questionnaire review, it was verified that ancient legends are still valid, fear predominate when snakes are the topic and inadequate methods of first aid is still in use. Some beliefs were confronted and doubts clarified during the debate, enabling to see snakes in a more reliable way. Colocados rotineiramente na berlinda pelas mídias sociais, as serpentes são animais rodeados de estórias e mistérios. A fim de investigar as visões culturais sobre serpentes, foram analisados filmes comerciais que têm esses animais como assunto central. Algumas cenas foram selecionadas e editadas para a produção de um curta (também utilizado como material didático. Foram trabalhados os conhecimentos prévios sobre serpentes de universitários de Pedagogia através de um questionário seguido pela exibição do curta e um debate. Após análise, percebeu-se que os filmes geralmente exploram o tema de maneira exagerada, mesclando científico e imaginário. O questionário evidenciou que lendas antigas ainda são vigentes, que o medo predomina quando se trata de serpentes e que métodos inadequados de primeiros socorros a acidentes ofídicos ainda são utilizados. O debate permitiu confrontar crenças e esclarecer dúvidas, contribuindo para uma visão mais realística sobre esses animais.

  13. Authenticity test in ceramics and archaeological figures by thermoluminescence

    International Nuclear Information System (INIS)

    Ramirez L, A.; Schaaf, P.; Filloy, L.

    1999-01-01

    At present exists quite a lot of false archaeological pieces which provokes doubts about the legitimacy of the pieces. In this work it is presented the Authenticity test by Thermoluminescence realized at the urn of the goddess 13 serpent of the zapotec culture of Oaxaca which is exposed in Mexico City. The original piece contains crystalline structures which present hardly the thermoluminescence phenomena by the presence of 238 U, 232 Th, and 40 K getting with this the form and intensity of the natural thermoluminescence curve of an archaeological piece which shows a Tl peak and allows to know so if it was made recently or not. (Author)

  14. Toward Reanalysis of the Tight-Pitch HCLWR-PROTEUS Phase II Experiments

    Directory of Open Access Journals (Sweden)

    Perret Grégory

    2016-01-01

    Spectral index predictions using the three nuclear data libraries agreed within two standard deviations with the measured values. The only exception is the Pu-242-capture-to-Pu-239-fission ratio, which was overestimated with all libraries by more than four standard deviations, i.e. 13%, in the non-moderated configuration. In this configuration, Pu-242 captures are few since the flux spectrum in the Pu-242 capture resonance region (between 1eV and 1keV is small making this spectral index hard to measure. Sensitivity coefficient predictions with both MCNP6 and SERPENT2 were in good agreement.

  15. Kult boha Quetzalcóatla v indiánských civilizacích Mezoameriky

    OpenAIRE

    DOHNALOVÁ, Barbora

    2013-01-01

    The aim of this bachelor thesis is to present the role of Quetzalcóatl in the Indian civilizations of Mesoamerica. The work focuses on the cult of the Feathered Serpent in the pre-Columbian period. In the first part the author approaches Mesoamerican cultural-geographic area, provides a short overview of the most significant civilizations and than focuses on the religion beliefs of native population. The next part of the thesis takes special attention to the own part of the cult of Quetzalcoa...

  16. Neutron analysis of the fuel of high temperature nuclear reactors

    International Nuclear Information System (INIS)

    Bastida O, G. E.; Francois L, J. L.

    2014-10-01

    In this work a neutron analysis of the fuel of some high temperature nuclear reactors is presented, studying its main features, besides some alternatives of compound fuel by uranium and plutonium, and of coolant: sodium and helium. For this study was necessary the use of a code able to carry out a reliable calculation of the main parameters of the fuel. The use of the Monte Carlo method was convenient to simulate the neutrons transport in the reactor core, which is the base of the Serpent code, with which the calculations will be made for the analysis. (Author)

  17. Towards a reconstruction of the contributions of the Argentine experience to the development of International Human Rights Law: the voices of Claudia Fontes and Paula Bombara

    Directory of Open Access Journals (Sweden)

    Estefanía Giaccone

    2017-12-01

    Full Text Available In the present dissertation, we intend to relate and contrast the representations that emerge from legal and political-institutional discourses on the crime of forced disappearance of persons in the Argentinian historical experience. In this sense, we will analyze the representations of the crime of forced disappearance of persons in two artistic works: The Reconstruction of Pablo Miguez Portrait, Claudia Fontes’ sculpture, and The Sea and the Serpent, a novel by Paula Bombara, in order to read them into the perspective of law, with the jurisprudence and communications of international organizations that shape our unit of study.

  18. Authenticity test in ceramics and archaeological figures by thermoluminescence; Prueba de Autenticidad en ceramicas y figuras arqueologicas por termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez L, A.; Schaaf, P. [Laboratorio de Termoluminiscencia, Instituto de Geofisica-UNAM (Mexico); Filloy, L. [Museo Nacional de Antropologia e Historia, Ciudad de Mexico (Mexico)

    1999-07-01

    At present exists quite a lot of false archaeological pieces which provokes doubts about the legitimacy of the pieces. In this work it is presented the Authenticity test by Thermoluminescence realized at the urn of the goddess 13 serpent of the zapotec culture of Oaxaca which is exposed in Mexico City. The original piece contains crystalline structures which present hardly the thermoluminescence phenomena by the presence of {sup 238} U, {sup 232} Th, and {sup 40} K getting with this the form and intensity of the natural thermoluminescence curve of an archaeological piece which shows a Tl peak and allows to know so if it was made recently or not. (Author)

  19. A functional method for estimating DPA tallies in Monte Carlo calculations of Light Water Reactors

    International Nuclear Information System (INIS)

    Read, Edward A.; Oliveira, Cassiano R.E. de

    2011-01-01

    There has been a growing need in recent years for the development of methodology to calculate radiation damage factors, namely displacements per atom (dpa), of structural components for Light Water Reactors (LWRs). The aim of this paper is to discuss the development and implementation of a dpa method using Monte Carlo method for transport calculations. The capabilities of the Monte Carlo code Serpent such as Woodcock tracking and fuel depletion are assessed for radiation damage calculations and its capability demonstrated and compared to those of the Monte Carlo code MCNP for radiation damage calculations of a typical LWR configuration. (author)

  20. Acidente ofídico no estado de Goiás

    Directory of Open Access Journals (Sweden)

    Pinho Fábia Maria Oliveira

    2004-01-01

    Full Text Available OBJETIVO: Avaliar aspectos epidemiológicos dos acidentes por serpentes peçonhentas ocorridos no Estado de Goiás. MÉTODOS: Foram analisadas ''Fichas de investigação de acidentes por animais peçonhentos'', pertencentes ao sistema de notificação da Secretaria de Saúde do Estado de Goiás, no triênio 1998-2000. RESULTADOS: Foram notificados, neste período, 3.261 acidentes por serpentes peçonhentas, com coeficiente de incidência variando entre 20 e 23/100.000 habitantes. O maior número de casos ocorreu entre os meses de outubro e abril. Dentre os 2.350 casos em que houve referência ao gênero da serpente, 78,6% foram causados por Bothrops, 20,8% por Crotalus e 6% por Micrurus. Houve predominância do sexo masculino (78,5% e com faixa etária entre 20 e 39 anos de idade. As regiões anatômicas mais freqüentemente picadas foram: pé (43,6%, pernas (23,2% e mãos (20,1%. Em relação ao tempo de atendimento, mais de 80% dos envenenamentos foram atendidos com menos de 6 horas da picada. Os envenenamentos foram classificados, de acordo com a gravidade, em leves (31,6%, moderados (47,5% ou graves (9,6%. As complicações mais comuns foram necrose tecidual no local da picada (31,8% nos envenenamentos botrópicos e insuficiência renal aguda (1,2% nos envenenamentos crotálicos. A letalidade geral foi de 0,46%, sendo a maior taxa observada entre acidentes crotálicos (1%. CONCLUSÕES: Acidentes por serpentes peçonhentas no Estado de Goiás acometem principalmente a população jovem do sexo masculino e têm sido causa de óbito.

  1. When the dragon wore the crown putting starlight back into myth

    CERN Document Server

    Cerow, Don

    2013-01-01

    When our ancestors gazed upon the skies thousands of years ago they looked up into the center of Creation and saw a mighty Dragon, a great celestial serpent with wings circling ceaselessly above them, night after night, century after century. When the Dragon Wore the Crown is a ground breaking book that covers a period of over six thousand years, focusing on what astrologers would call the Ages of Gemini, Taurus and Aries and taking us through the period of classical astronomy with the Greeks and Romans (approx. 7000 BC-200 AD).When the Dragon Wore the Crown opens and closes with the Chinese m

  2. Pengembangan Sistem Keamanan untuk E-Commerce

    Directory of Open Access Journals (Sweden)

    I Gusti Ngurah Indra Saputra

    2017-07-01

    Full Text Available E-commerce is a remote goods or services transaction activity between two company (business to business or between company with customers (business to consumer. Ecommerce was simplifying the transaction process between producers and consumers, butthere is a risk of security issue if doing transactions on e-commerce. A common e-commercesecurity system using another protocol security e.g. SSL (Secure Socket Layer so these ecommerce security system is very dependent with these security protocol. The e-commercesecurity problem was fixed by developed security system that using security system directly onthe web page. The system is designed to securing transaction data using RC6 encryption, RC6encryption key is secured by RSA encryption, and encrypted data is encoded by Base64. Theresulting security system is blocking transaction data when users clicking submit transactionbutton, then these transaction data encrypted using applied algorithm before send it into serverso transaction data was secured without aid of another security protocol e.g. SSL (SecureSocket Layer.

  3. An enhanced chaotic key-based RC5 block cipher adapted to image encryption

    Science.gov (United States)

    Faragallah, Osama S.

    2012-07-01

    RC5 is a block cipher that has several salient features such as adaptability to process different word lengths with a variable block size, a variable number of rounds and a variable-length secret key. However, RC5 can be broken with various attacks such as correlation attack, timing attack, known plaintext correlation attack and differential attacks, revealing weak security. We aimed to enhance the RC5 block cipher to be more secure and efficient for real-time applications while preserving its advantages. For this purpose, this article introduces a new approach based on strengthening both the confusion and diffusion operations by combining chaos and cryptographic primitive operations to produce round keys with better pseudo-random sequences. Comparative security analysis and performance evaluation of the enhanced RC5 block cipher (ERC5) with RC5, RC6 and chaotic block cipher algorithm (CBCA) are addressed. Several test images are used for inspecting the validity of the encryption and decryption algorithms. The experimental results show the superiority of the suggested enhanced RC5 (ERC5) block cipher to image encryption algorithms such as RC5, RC6 and CBCA from the security analysis and performance evaluation points of view.

  4. Mars Hand Lens Imager (MAHLI) Efforts and Observations at the Rocknest Eolian Sand Shadow in Curiosity's Gale Crater Field Site

    Science.gov (United States)

    Edgett, K. S.; Yingst, R. A.; Minitti, M. E.; Goetz, W.; Kah, L. C.; Kennedy, M. R.; Lipkaman, L. J.; Jensen, E. H.; Anderson, R. C.; Beegle, L. W.; hide

    2013-01-01

    The Mars Science Laboratory (MSL) mission is focused on assessing the past or present habitability of Mars, through interrogation of environment and environmental records at the Curiosity rover field site in Gale crater. The MSL team has two methods available to collect, process and deliver samples to onboard analytical laboratories, the Chemistry and Mineralogy instrument (CheMin) and the Sample Analysis at Mars (SAM) instrument suite. One approach obtains samples by drilling into a rock, the other uses a scoop to collect loose regolith fines. Scooping was planned to be first method performed on Mars because materials could be readily scooped multiple times and used to remove any remaining, minute terrestrial contaminants from the sample processing system, the Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA). Because of this cleaning effort, the ideal first material to be scooped would consist of fine to very fine sand, like the interior of the Serpent Dune studied by the Mars Exploration Rover (MER) Spirit team in 2004 [1]. The MSL team selected a linear eolian deposit in the lee of a group of cobbles they named Rocknest (Fig. 1) as likely to be similar to Serpent Dune. Following the definitions in Chapter 13 of Bagnold [2], the deposit is termed a sand shadow. The scooping campaign occurred over approximately 6 weeks in October and November 2012. To support these activities, the Mars Hand Lens Imager (MAHLI) acquired images for engineering support/assessment and scientific inquiry.

  5. Ophidascaris wangi sp. n. and O. najae (Gedoelst, 1916) (Ascaridida: Ascaridoidea) from snakes in China.

    Science.gov (United States)

    Li, Liang; Guo, Yan-Ning; Li, Jian; Zhang, Lu-Ping

    2014-12-01

    Ophidascaris wangi sp. n. collected from the king rat snake Elaphe carinata (Günther) (Serpentes: Colubridae) in China is described using both light and scanning electron microscopy. The new species differs from its congeners in the presence of narrow lateral alae originating a short distance posterior to the base of the ventrolateral lips, its relatively long oesophagus (3.57-4.54 mm long, representing 6.6-7.6% of body length), its short spicules (1.89-2.14 mm long, representing 3.9-4.3% of body length), the number and arrangement of caudal papillae (49-57 pairs in total, arranged as follows: 43-51 pairs precloacal, 2 pairs joined paracloacal and 4 pairs postcloacal), the presence of a particular papilliform medioventral, postcloacal ornamentation and the morphology of the eggs and tip of the female tail. In addition, Ophidascaris najae (Gedoelst, 1916), collected from the king cobra Ophiophagus hannah Cantor (Serpentes: Elapidae) in China, is also redescribed. The morphology of the cervical papillae, labial denticles and phasmids of the female is described for the first time.

  6. Post decommissioning monitoring of uranium mines; a watershed monitoring program based on biological response

    International Nuclear Information System (INIS)

    Russel, C.; Coggan, A.; Ludgate, I.

    2006-01-01

    Rio Algom Limited and Denison Mines own and operated uranium mines in the Elliot Lake area. The mines operated from the late 1950's to the mid 1960's and again for the early 1970's to the 1990's when the mines ceased operations. There are eleven decommissioned mines in the Serpent River watershed. At the time of decommissioning each mine had it's own monitoring program, which had evolved over the operating life of the mine and did not necessarily reflect the objectives associated with the monitoring of decommissioned sites. In order to assess the effectiveness of the decommissioning plans and monitoring the cumulative effects within the watershed, a single watershed monitoring program was developed in 1999: the Serpent River Watershed Monitoring Program which focused on water and sediment quality within the watershed and response of the biological community over time. In order to address other 'source area' monitoring, three complimentary objective-focused programs were developed 1) the In- Basin Monitoring Program, 2) the Source Area Monitoring Program and 3) the TMA Operational Monitoring Program. Through development this program framework and monitoring programs that were objective- focused, more meaningful data has been provided while providing a significant reduction in the cost of monitoring. These programs allow for the reduction in scope over time in response to improvement in the watershed. This talk will describe the development of these programs, their implementation and effectiveness. (author)

  7. Observations on stake holder confidence related to uranium mine waste management in the elliot lake region

    International Nuclear Information System (INIS)

    MacDonald, G.

    2003-01-01

    G. MacDonald, representing the Township of the North Shore and the Standing Environmental Committee (SEC) of the Serpent River Watershed, stated that she is a stakeholder living downstream from 175 million tonnes of acid-generating and radioactive uranium mine tailings. Public confidence in the Elliot Lake region is influenced by past mining issues: worker health concerns and difficulties in obtaining compensation; myriad observations of radium uptake; drinking water contamination issues and inequitable quality standards adverse to the Serpent River First Nation; loss of land use. Government failed to set aside funds for local monitoring of the decommissioned mining region, or to involve citizens in decisions as recommended by the Kirkwood Panel. These failures represent betrayals of trust and furthermore give public confidence little chance to improve. In these circumstances, the affected community has given attention on their own to mid- and long-term issues. At issue is not the current funding or management of the waste storage sites, but rather, creating and maintaining local knowledge and competence to monitor their management over the coming decades and generations. Concerned members of the community note that the federal government 'has done nothing long-lasting to ensure confidence', on this level. They highlight the importance of questions like: 'Do I have the knowledge to act in my best interest?' and 'Who can I trust to protect my interest?' - and have set out to answer them. (author)

  8. Polyarnye siyaniya sistemy avroral'nogo ovala kak kosmoloficheskij obraz drevnej mifologii %t The northern light of the auroral oval system as a cosmological concept of the archaic mythology

    Science.gov (United States)

    Alekseeva, L. M.

    Since archaic epochs people attentively observe the sky. They used to associate the sky phenomena with gods, heroes, spirits, etc. People interpreted the regularities in the motion of celestial objects in terms of their mythological model of the Universe. These observations and interpretations were first steps of the archaeoastronomy. Many remarkable features are inherent in the patterns of northern lights of the auroral oval system. Their manifestations are fairly regular. Did the ancients observe and some how classify these northern light phenomena? If yes, with which mythological personages were they associated? When were studies of the polar lights initiated? The present work is an attempt to answer these questions. We shall see that the ancient people assumed the spirit-world to be situated on the North. If so, it should manifest itself in spectacular polar aurorae. The specifically northern mythic cosmology formed the basis for Slavic fairy tales (theme of the Serpent and Serpent Fighter) and folk-beliefs. Other inhabitants of snowy latitudes should also manifest similar views. Studying the mythological reflections of typical auroral phenomena, it is possible to trace up long-standing ideological trends from the late glaciation epoch to the present time. Our results can help geophysicists in studying paleoauroral phenomena.

  9. Is Continuing Contumely Relative to Mc Leod's Vision and ``Secret Sacred Science, (SSS),'': Contagiously Counterproductive in Science, or an Unhealthy Artifact of ``Turf Wars''?

    Science.gov (United States)

    Leod, Roger

    2007-04-01

    Mc Leod confirmed, with physics, his models for vision, and for electromagnetic artifacts, by traditional methods, associated with phenomena like tornados, hurricanes, and earthquakes. The latter confirmations are evidently apparent across current ethnology, cultures, linguistics, religion, rituals, exotic astronomy, somewhat concealed evidence of native record-keeping/writing, and iconography. Use of cultural anthropology while observing a modern Peruvian sacred-site-sweeping at Cuzco, coupled with their assertion that Ñari Huallac means ``serpent God,'' plus electromagnet information, reveals that their religious world-view include(s)(d) applied science that is still otherwise unacknowledged. Alexander Thom's precise megalithic site-measurements also imply that ``The Ancients' Serpent'' made/makes precise tracks that convey valuable information. The linguistics of words like Seminole, and unusual visual effects, reveal some traditionalists have done better than most scientists, for vision, and observational physics, and earth science. Tornado and hurricane tracks are predictable, as are some earthquakes. Tornado ``detuning'' or shutdown is electromagnetically possible. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.7

  10. Calculating the effective delayed neutron fraction in the Molten Salt Fast Reactor: Analytical, deterministic and Monte Carlo approaches

    International Nuclear Information System (INIS)

    Aufiero, Manuele; Brovchenko, Mariya; Cammi, Antonio; Clifford, Ivor; Geoffroy, Olivier; Heuer, Daniel; Laureau, Axel; Losa, Mario; Luzzi, Lelio; Merle-Lucotte, Elsa; Ricotti, Marco E.; Rouch, Hervé

    2014-01-01

    Highlights: • Calculation of effective delayed neutron fraction in circulating-fuel reactors. • Extension of the Monte Carlo SERPENT-2 code for delayed neutron precursor tracking. • Forward and adjoint multi-group diffusion eigenvalue problems in OpenFOAM. • Analytical approach for β eff calculation in simple geometries and flow conditions. • Good agreement among the three proposed approaches in the MSFR test-case. - Abstract: This paper deals with the calculation of the effective delayed neutron fraction (β eff ) in circulating-fuel nuclear reactors. The Molten Salt Fast Reactor is adopted as test case for the comparison of the analytical, deterministic and Monte Carlo methods presented. The Monte Carlo code SERPENT-2 has been extended to allow for delayed neutron precursors drift, according to the fuel velocity field. The forward and adjoint eigenvalue multi-group diffusion problems are implemented and solved adopting the multi-physics tool-kit OpenFOAM, by taking into account the convective and turbulent diffusive terms in the precursors balance. These two approaches show good agreement in the whole range of the MSFR operating conditions. An analytical formula for the circulating-to-static conditions β eff correction factor is also derived under simple hypotheses, which explicitly takes into account the spatial dependence of the neutron importance. Its accuracy is assessed against Monte Carlo and deterministic results. The effects of in-core recirculation vortex and turbulent diffusion are finally analysed and discussed

  11. Aspectos ecológicos e epidemiológicos de acidentes ofídicos em comunidades ribeirinhas do baixo rio Purus, Amazonas, Brasil Ecological and epidemiological aspects of snakebites in riverside communities of the lower Purus River, Amazonas, Brazil

    Directory of Open Access Journals (Sweden)

    Fabiano Waldez

    2009-09-01

    Full Text Available Acidentes ofídicos foram registrados em dez comunidades ribeirinhas do baixo rio Purus através de entrevista às vítimas. Os ribeirinhos responderam perguntas sobre a percepção ambiental da ecologia das serpentes envolvidas nos acidentes. O tamanho das serpentes e a altura da mordida no corpo foram estimados com fita métrica. A correspondência entre os nomes locais e científicos das serpentes foi levantada utilizando descrições e imagens das espécies. Para outras 17 comunidades dados adicionais do número de famílias com vítimas de acidentes ofídicos foram avaliados através do diagnóstico sócio-ambiental da Reserva de Desenvolvimento Sustentável Piagaçu-Purus. Foram entrevistados 18 ribeirinhos e registrados 28 acidentes ofídicos em cinco comunidades. O número de vítimas por comunidade não teve relação com o tamanho da população. O número de famílias com vítimas foi maior em comunidades maiores (r²= 0,444; p= 0,003. Aproximadamente 88% das mordidas foram nos membros inferiores. Não houve relação do tamanho estimado da serpente com a altura da mordida. A maioria dos acidentes ocorreu de dia (82,14% e no período de cheia (64,28% na época de exploração da castanha-da-Amazônia e da madeira pelos ribeirinhos, atividades que despendem maior tempo na floresta. Um único caso de morte por acidente ofídico foi registrado. A serpente Bothrops atrox foi à espécie mais relacionada com acidentes na região. O reconhecimento das serpentes pelos ribeirinhos revelou várias sinonímias, com 20 nomes locais atribuídos a 33 espécies. Na percepção dos ribeirinhos as serpentes B. atrox e Lachesis muta foram às espécies mais temidas e diferem no comportamento de ataque.Snakebites were registered in 10 riverside communities of the lower Purus River through interviews with the victims. Local inhabitants answered questions about their perception on ecological aspects of snakes species involved in snakebites. Snake size

  12. DATA SECURITY IN LOCAL AREA NETWORK BASED ON FAST ENCRYPTION ALGORITHM

    Directory of Open Access Journals (Sweden)

    G. Ramesh

    2010-06-01

    Full Text Available Hacking is one of the greatest problems in the wireless local area networks. Many algorithms have been used to prevent the outside attacks to eavesdrop or prevent the data to be transferred to the end-user safely and correctly. In this paper, a new symmetrical encryption algorithm is proposed that prevents the outside attacks. The new algorithm avoids key exchange between users and reduces the time taken for the encryption and decryption. It operates at high data rate in comparison with The Data Encryption Standard (DES, Triple DES (TDES, Advanced Encryption Standard (AES-256, and RC6 algorithms. The new algorithm is applied successfully on both text file and voice message.

  13. Psychometric Evaluation of the MMPI-2/MMPI-2-RF Restructured Clinical Scales in an Israeli Sample.

    Science.gov (United States)

    Shkalim, Eleanor

    2015-10-01

    The current study cross-culturally evaluated the psychometric properties of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2)/MMPI-2-Restructured Form Restructured Clinical (RC) Scales in psychiatric settings in Israel with a sample of 100 men and 133 women. Participants were administered the MMPI-2 and were rated by their therapists on a 188-item Patient Description Form. Results indicated that in most instances the RC Scales demonstrated equivalent or better internal consistencies and improved intercorrelation patterns relative to their clinical counterparts. Furthermore, external analyses revealed comparable or improved convergent validity (with the exceptions of Antisocial Behavior [RC4] and Ideas of Persecution [RC6] among men), and mostly greater discriminant validity. Overall, the findings indicate that consistent with previous findings, the RC Scales generally exhibit comparable to improved psychometric properties over the Clinical Scales. Implications of the results, limitations, and recommendations for future research are discussed. © The Author(s) 2014.

  14. Bare Bones: A Method for Estimating Provisioning Budget Requirements in the Outyears

    Science.gov (United States)

    1977-07-01

    8217 .; ’ ; . ’-COMMON/PART/NSS, BF, U, UP, UPNHA, V( 6), PC 6), TAT( 6), OSTC 6> - COMMON/GENRL/VSUMC 65, PSLWC 6), QW, QIC 6),.Q2C 6), QOLC 6>, QEC 6...COM.-IO^/GEMRL/VSU^C 6), PSIM( 6), Q’ttJj QIC 6), Q2( 6), QOLC 6) ^ QEC 6), DIMENSION RC 6) YR=365. " " • . USLMC 1)=PSUMC 1) = Q=0. DO...10 J=2, JJ ^ . vsiw< J) = VSOMC j-n+u< j) ■ , PSU^C J) = PSUMC J-l ) + PC J) Ql (J)=02C J)= QOLC J)= QEC J) = 0. EO 1 5 J=2, JJ- 1

  15. Evaluation of CANDU6 PCR (power coefficient of reactivity) with a 3-D whole-core Monte Carlo Analysis

    International Nuclear Information System (INIS)

    Motalab, Mohammad Abdul; Kim, Woosong; Kim, Yonghee

    2015-01-01

    Highlights: • The PCR of the CANDU6 reactor is slightly negative at low power, e.g. <80% P. • Doppler broadening of scattering resonances improves noticeably the FTC and make the PCR more negative or less positive in CANDU6. • The elevated inlet coolant condition can worsen significantly the PCR of CANDU6. • Improved design tools are needed for the safety evaluation of CANDU6 reactor. - Abstract: The power coefficient of reactivity (PCR) is a very important parameter for inherent safety and stability of nuclear reactors. The combined effect of a relatively less negative fuel temperature coefficient and a positive coolant temperature coefficient make the CANDU6 (CANada Deuterium Uranium) PCR very close to zero. In the original CANDU6 design, the PCR was calculated to be clearly negative. However, the latest physics design tools predict that the PCR is slightly positive for a wide operational range of reactor power. It is upon this contradictory observation that the CANDU6 PCR is re-evaluated in this work. In our previous study, the CANDU6 PCR was evaluated through a standard lattice analysis at mid-burnup and was found to be negative at low power. In this paper, the study was extended to a detailed 3-D CANDU6 whole-core model using the Monte Carlo code Serpent2. The Doppler broadening rejection correction (DBRC) method was implemented in the Serpent2 code in order to take into account thermal motion of the heavy uranium nucleus in the neutron-U scattering reactions. Time-average equilibrium core was considered for the evaluation of the representative PCR of CANDU6. Two thermal hydraulic models were considered in this work: one at design condition and the other at operating condition. Bundle-wise distributions of the coolant properties are modeled and the bundle-wise fuel temperature is also considered in this study. The evaluated nuclear data library ENDF/B-VII.0 was used throughout this Serpent2 evaluation. In these Monte Carlo calculations, a large number

  16. Influenza em animais heterotérmicos Influenza in heterothermics

    Directory of Open Access Journals (Sweden)

    Dalva Assunção Portari Mancini

    2004-06-01

    Full Text Available O objetivo foi pesquisar Ortomyxovirus em animais heterotérmicos. Coletou-se sangue de serpentes dos gêneros Bothrops e Crotalus e de sapo e rãs dos gêneros Bufo e Rana, para a detecção dos receptores de hemácias e anticorpos específicos, ao vírus influenza, pelos testes de hemaglutinação e inibição da hemaglutinação, respectivamente. Pelo teste de hemaglutinação, verificou-se que serpentes e sapos em cativeiro apresentaram receptores em suas hemácias para o vírus influenza, humano e eqüino do tipo A e tipo B. O mesmo ocorreu com serpentes recém chegadas. Quanto ao teste de inibição da hemaglutinação dos soros dos répteis observou-se títulos protetores de anticorpos aos vírus influenza tipo A (origens humana e eqüina e tipo B. Com soro de sapo não se observou reação de inibição da hemaglutinação porém, 83,3% das rãs obtiveram médias de 40UIH para algumas cepas. Conclui-se que animais heterotérmicos podem oferecer condições de hospedeiros aos vírus influenza, assim como susceptibilidade à infecção.The objective was to study Orthomyxovirus in heterothermic animals. Blood samples from snakes (genus Bothrops and Crotalus and from toads and frogs (genus Bufo and Rana were collected to evaluate the red cell receptors and antibodies specific to influenza virus by the hemagglutination and hemagglutination inhibition tests, respectively. Both snakes and toads kept in captivity presented receptors in their red cells and antibodies specific to either influenza virus type A (human and equine origin or influenza type B. The same was observed with recently captured snakes. Concerning the influenza hemagglutination inhibition antibodies protective levels were observed in the reptiles' serum, against influenza type A and type B. Unlike the toads, 83.3% of the frogs presented mean levels of Ab 40HIU for some influenza strains. It was concluded that heterothermic animals could offer host conditions to the influenza

  17. Activity of Antifungal Organobismuth(III Compounds Derived from Alkyl Aryl Ketones against S. cerevisiae: Comparison with a Heterocyclic Bismuth Scaffold Consisting of a Diphenyl Sulfone

    Directory of Open Access Journals (Sweden)

    Toshihiro Murafuji

    2014-07-01

    Full Text Available A series of hypervalent organobismuth(III compounds derived from alkyl aryl ketones [XBi(5-R'C6H3-2-COR(Ar] was synthesized to investigate the effect of the compounds’ structural features on their antifungal activity against the yeast Saccharomyces cerevisiae. In contrast to bismuth heterocycles [XBi(5-RC6H3-2-SO2C6H4-1'-] derived from diphenyl sulfones, a systematic quantitative structure-activity relationship study was possible. The activity depended on the Ar group and increased for heavier X atoms, whereas lengthening the alkyl chain (R or introducing a substituent (R' reduced the activity. IBi(C6H4-2-COCH3(4-FC6H4 was the most active. Its activity was superior to that of the related acyclic analogues ClBi[C6H4-2-CH2N(CH32](Ar and ClBi(C6H4-2-SO2 tert-Bu(Ar and also comparable to that of heterocyclic ClBi(C6H4-2-SO2C6H4-1'-, which was the most active compound in our previous studies. Density function theory calculations suggested that hypervalent bismuthanes undergo nucleophilic addition with a biomolecule at the bismuth atom to give an intermediate ate complex. For higher antifungal activity, adjusting the lipophilicity-hydrophilicity balance, modeling the three-dimensional molecular structure around the bismuth atom, and stabilizing the ate complex appear to be more important than tuning the Lewis acidity at the bismuth atom.

  18. Optimization of the fuel assembly for the Canadian SuperCritical Water-cooled Reactor (SCWR)

    Energy Technology Data Exchange (ETDEWEB)

    French, C., E-mail: Corey.French@cnsc-ccsn.gc.ca [Canadian Nuclear Safety Commission, Ottawa, Ontario (Canada); Bonin, H.; Chan, P.K. [Royal Military College of Ontario, Kingston, Ontario (Canada)

    2013-07-01

    An approach to develop a parametric optimization tool to support the Canadian Supercritical Water-cooled Reactor (SCWR) fuel design is presented in this work. The 2D benchmark lattices for 78-pin and 64-pin fuel assemblies are used as the initial models from which fuel performance and subsequent optimization stem from. A tandem optimization procedure is integrated which employs the steepest descent method. The physics codes WIMS-AECL, MCNP6 and SERPENT are used to calculate and verify select performance factors. The results are used as inputs to an optimization algorithm that yield optimal fresh fuel isotopic composition and lattice geometry. Preliminary results on verifications of infinite lattice reactivity are demonstrated in this paper. (author)

  19. Bioengineering and Cybernetics: A Modern Caduceus.

    Science.gov (United States)

    Magin, Richard L

    2017-01-01

    Like the caduceus, a medical symbol of entwined serpents, bioengineering and cybernetics have interwoven together ideas and concepts for over 50 years. Half a century is a long time, and whether we are talking about an academic discipline, our lives, or an old car, achieving 50 is a number that brings pause to the conversation. In books, wine, or collectibles, 50 years is termed vintage, which carries the connotation of depth and maturity. Certainly, in the case of the discipline of bioengineering, 50 years is a milestone of growth and development. By all academic measures (number of departments, current enrollment and graduates, size of faculty, and impact factor for its publications), bioengineering is a mature discipline. Presently, there are almost 100 ABET-certified bioengineering degree programs in the United States alone.

  20. On Monte Carlo estimation of radiation damage in light water reactor systems

    International Nuclear Information System (INIS)

    Read, Edward A.; Oliveira, Cassiano R.E. de

    2010-01-01

    There has been a growing need in recent years for the development of methodologies to calculate damage factors, namely displacements per atom (dpa), of structural components for Light Water Reactors (LWRs). The aim of this paper is discuss and highlight the main issues associated with the calculation of radiation damage factors utilizing the Monte Carlo method. Among these issues are: particle tracking and tallying in complex geometries, dpa calculation methodology, coupled fuel depletion and uncertainty propagation. The capabilities of the Monte Carlo code Serpent such as Woodcock tracking and burnup are assessed for radiation damage calculations and its capability demonstrated and compared to those of the MCNP code for dpa calculations of a typical LWR configuration involving the core vessel and the downcomer. (author)

  1. Estudos conformocionais de diversas proteínas em solução utilizando a técnica de espalhamento de raios-X à baixo ângulo-saxs

    OpenAIRE

    Viçoti, Magno Massolino [UNESP

    2011-01-01

    A técnica de espalhamento de raios-X a baixo ângulo – SAXS é uma poderosa ferramenta para a caracterização de macromoléculas biológicas em solução. Aplicando-a de forma correta podemos obter parâmetros físicos à respeito do material de estudo, como raio de giração, máxima dimensão, volume e superfície. Neste trabalho caracterizou-se em solução aquosa a macromolécula heterodimérica crotoxina com a variação do pH em ácido, básico e neutro. Esta proteína foi isolada da serpente sul-americana Cro...

  2. Restoration of environments with radioactive residues - the Elliot Lake case study

    International Nuclear Information System (INIS)

    Knapp, R.A.

    2000-01-01

    The Elliot Lake area experienced the boom and bust of uranium mining over a 40-year period. In 1996, the last mine closed, which left nine tailings areas for closure and long term maintenance. The practices of the 1950s left a legacy of environmental damage which has been effectively reversed through remediation and closure of the mines. Detailed environmental assessments were completed on decommissioning proposals for the mines in the late 1980s and 1990s. These assessments have demonstrated that the area's ecology can be effectively protected, and that there are no impediments to the restoration of the entire Serpent River Watershed. Environmental monitoring has shown that the reclaimed sites are performing as expected, and that healthy aquatic communities are present in all major waterways in the region. (author)

  3. Teotihuacan and its influence in Mesoamerica. Archaeomagnetic studies

    Science.gov (United States)

    Terán, A.; Soler-Arechalde, A. M.

    2013-05-01

    Teotihuacan located at the north of the Basin of Mexico was one of the most important metropolises of Mesoamerica between AD 300-500. The chronological information of the city and its neighborhoods is very important to understand its evolution. We present the results of the sampling at the Feathered Serpent Temple and E complex at La Ciudadela, a zone at the south area of the Pyramids of the Sun and the Moon. These results correspond with a stratigraphic sequence between the 50 BC to AD 500. Two ritual events related with the beginning and the end of the Xolalpan stage (AD325-AD545) were archaeomagnetic dated, events that had been observed too at Teopancazco, the neighborhood of the taylors located at the SE of the city, denoting the importance of them. The beginning of Xolalpan stage is related with the exile of a group of teotihuacan warriors that arrived to Tikal.

  4. Did Secret, Sacred Science: ``Kokopelli/Pamola,'' Motivate the Tarratines' Assassination of the Penobscots' Bashaba ca 1615, and Does ``Orono'' Yield Direct Physics Insights?

    Science.gov (United States)

    Ataide, Italani; de Souza, Beatriz; Pawa Matagamon, Sagamo

    2007-04-01

    ``Tarratine'' may share cognate phonetics with Tatoosh, (Makah, Pacific NE), Tuitan, Totonac, (coastal ``neighbors'' of the Aztec), Teedyuscung/Tatiuskundt, (Penn.), Teotihuacan, Tomtomhegan, (``ME'' ca 1781-2), Titikaka/Titicaca, and Tantaquidgeon, (Conn.); the military action that led to the assassination of the Penobscots' Bashaba has explanatory roots tying it to the last raid involving `Indian' military action of the Revolutionary War. ``Turf'' rights influenced conflict imperatives. Preserved linguistic roots have it best: Ñari Huallac, coupled with Arizona, Allagash, Allahpatah, and Orono/Orinoco, indicate traditionalists' information, by recognizing Kokopelli/Pamola/Pele/electromagnetics/EMF, says how nature behaves. Penobscots and modern Peruvian descendants of the Incas have it right: the concealed ``Serpent God'' of their EMF alter ego(s), says their science, (applied physics) is sacred because it ``predicts'' nature, even tinnitus, via ``Rawandagon''! To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.8

  5. Snakes as hazards: modelling risk by chasing chimpanzees.

    Science.gov (United States)

    McGrew, William C

    2015-04-01

    Snakes are presumed to be hazards to primates, including humans, by the snake detection hypothesis (Isbell in J Hum Evol 51:1-35, 2006; Isbell, The fruit, the tree, and the serpent. Why we see so well, 2009). Quantitative, systematic data to test this idea are lacking for the behavioural ecology of living great apes and human foragers. An alternative proxy is snakes encountered by primatologists seeking, tracking, and observing wild chimpanzees. We present 4 years of such data from Mt. Assirik, Senegal. We encountered 14 species of snakes a total of 142 times. Almost two-thirds of encounters were with venomous snakes. Encounters occurred most often in forest and least often in grassland, and more often in the dry season. The hypothesis seems to be supported, if frequency of encounter reflects selective risk of morbidity or mortality.

  6. Spatial patterns and biodiversity conservation of snakes from Cerrado biome

    OpenAIRE

    Couto, Larice de Fátima; UCG; Terribile, Levi Carina; UNB; Diniz Filho, José Alexandre Felizola; UFG

    2007-01-01

    Em geral, as tentativas para estabelecer áreas prioritárias para conservação no Cerrado têm sido baseadas em critérios subjetivos. No presente trabalho, foram utilizados dados macroecológicos de distribuição de 129 espécies de serpentes distribuídas em 181 células com 1o de latitude/longitude do Cerrado para analisar padrões espaciais na riqueza e propor uma estratégia de conservação para essas espécies. Verificou-se que as cinco variáveis ambientais analisadas explicaram apenas 34,65% da var...

  7. Arvustused / Jan Berkovitch

    Index Scriptorium Estoniae

    Berkovitch, Jan

    2007-01-01

    Heliplaatidest: Municipal Waste "The Art Of Partying", Fueled By Fire "Spread The Fire", Apocryphal Voice "Stilltrapped", Amorphis "Silent Waters", As I Lay Dying "An Ocean Between Us", Baroness "Red Album", Behemoth "The Apostasy", Beherit "H418ov21.C / Electric Doom Synthesis", Cephalic Carnage "Xenosapien", Beneath The Massacre "Mechanics Of Dysfunction", Crionics "Neuthrone", Depressed Mode "Ghosts Of Devotion", Down "III - Over The Under", Drudkh "Estrangement", Einstürzende Neubauten "Alles Wieder Offen", Entombed "Serpent Saints - The Ten Amendments", Fall Of The Leafe "Aerolithe", Helena Nova "Vaenlasega voodis", King Diamond "Give Me Your Soul... Please!", Manes "How The World Came To An End", Must Missa "Martyr Of Wrath", Mustasch "Latest Version Of Truth", Nile "Ithyphallic", Pig Destroyer "Phantom Limb", Reverend Bizarre "Ill: So Long Suckers", Terhen "Eyes Unfolded", Throne Of Katarsis "An Eternal Dark Horizon", Tulus "Biography Obscene", Turbonegro "Retox", Weedeater "God Luck and Good Speed", Vreid "I Krig

  8. Estrutura das taxocenoses de lagartos nos biomas caatinga, cerrado e Amazônia.

    OpenAIRE

    Costa, Taís Borges

    2015-01-01

    A tese está dividida em três capítulos. No primeiro capítulo apresentamos a lista de espécies de répteis e anfíbios da Estação Ecológica de Aiuaba, Ceará, Brasil. Registramos 36 espécies distribuídas em 19 famílias para a unidade de conservação (15 lagartos, uma anfisbena, 10 serpentes, um quelônio e 9 anfíbios). No segundo capítulo investigamos a existência de padrões de estruturação, averiguando a influência dos fatores ecológicos e históricos, na dieta e no uso de microhábit...

  9. Origins of the ancient constellations: I. The Mesopotamian traditions

    Science.gov (United States)

    Rogers, J. H.

    1998-02-01

    In the sky-map of ancient Babylon, constellations had two different roles, and thus developed into two overlapping traditions. One set of constellations represented the gods and their symbols; the other set represented rustic activities and provided a farming calendar. Many constellations were shared by the two traditions, but in some regions of sky there were alternative divine and rustic figures. These figures developed in stages from ~3200 BC to ~500 BC. Of the divine set, the most important (although the last to be finalised) were the twelve zodiacal signs, plus several associated animals (the serpent, crow, eagle, and fish), which were all transmitted to the classical Greek sky-map that we still use today. Conversely, the rustic constellations of workers and tools and animals were not transmitted to the West. However, a few of them may have survived in Bedouin Arab sky-maps of the first millennium AD.

  10. [On gods, snakes and staffs--the emblem of the medical profession].

    Science.gov (United States)

    Rabinerson, David; Salzer, Liat; Gabbay-Benziv, Rinnat

    2014-10-01

    The commonly accepted emblems of the Medical Profession are the staff of the Greek god of medicine--Asklepios (or Asclepius], on which one serpent is entwined. Later, around the 16th century C.E., the wand of the herald of the Greek Gods, e.g., Hermes, on which two snakes are entwined and facing each other, became popular as the emblem of the medical profession. We elaborate on the history of the evolution of these emblems as symbols of medicine, including earlier influences from the times of the ancient Egyptians and Babylonians, which were followed by Judeo-Christian traditions and concepts. The relevance of the use of the wand of Hermes as an emblem of our profession is further discussed.

  11. Svetislav Basara, Perdu dans un supermarché

    Directory of Open Access Journals (Sweden)

    Katia Vandenborre

    2008-10-01

    Full Text Available Tomber amoureux dans le jazz de la nature quand on est pris d’élancements dans le bras. Souffrir d’un incurable serpent dans le sein après que sa mère ait été enlevée par des esclavagistes. Se dégonfler à la brûlure de cigarette lors d’une boum fatale. Discuter avec Dieu par téléphone dans un supermarché. Telles sont les aventures plus loufoques les unes que les autres dont Svetislav Basara nous tisse le décousu dans Perdu dans un supermarché. Ce recueil réunit une vingtaine de nouvelles liée...

  12. Transfer parameters in the water/forage/moose pathway

    International Nuclear Information System (INIS)

    1987-07-01

    Moose tissue samples and associated water and drinking water samples were collected from the Serpent River Drainage Area (Study Area) and outside of the watershed (Controls) during the fall of 1985. The concentrations of lead-210, polonium-210, radium-226, thorium and uranium were determined for both the study area and control samples. The radionuclide radium-226 was evaluated in the drinking water, vegetation and moose tissue to determine concentration factors. No statistical difference was found between study and control samples. Concentration factors from vegetation to moose tissue were found to range from 0.036 to 3.03 depending upon tissue type. Radionuclide concentrations found in this study were shown to be within known background levels. 2 maps

  13. Numerous Sinusoidal and Other EMF Phenomena, At Present and Former Native American Sites, May Be Superimposing Themselves onto Regional Power Grids.

    Science.gov (United States)

    Cadran, Lawrence R.; Mc Leod, Roger D.; Mc Leod, David M.

    2003-10-01

    Periodic electromagnetic field signals (EMF), sometimes noticeable as faint blue-light or other phenomena, frequently are also detected at sites associated with Native Americans. We first noticed this sort of information in the vicinity of Wendell, MA about fourteen years ago. Similar and other signals are apparent at Americas Stonehenge, AS, in North Salem, NH. Connecticut provided our first evidence of superposition of two such waves at the Gungywamp site north of Groton, CT. A Maine location first showed orthogonally oriented trajectories in neighborhoods formerly frequented by Molocket and Metallak and their relatives near Rumford and Rangeley, ME. Florida exhibits similar signals in the vicinity of Hollywood and at Miamis Tequesta instrument, as does a separate site in CT. Powerful thunderstorms in the vicinity of a stone serpent effigy in Ohio cause EMF pulsations. Such signals are possibly superimposing themselves onto power-grids, where frequency changes and system instabilities may occur, according to the elementary physics involved.

  14. Environmental Aspects of Sites Like America's Stonehenge, (AS), Florida's Miami Tequesta Site, and Lowell's A.D. 1069

    Science.gov (United States)

    Ochs, Michael Ann; Mc Leod, Roger D.

    2002-04-01

    Subtle ``instrumentation" is often unnoticed. Stone-chamber transponder-receivers are principle and secondary wave detectors, part of the ``technologic" arsenal of men like Passaconaway/Metacomen of colonial-era Massachusetts, or the earthquake-predicting Shawnee Tecumseh of the Ohio Valley region, during 1811-1813. An Ohio stone-effigy ``serpent" is a thunderstorm precursor signal indicator. The Hopi require similar ``equipment," when duping gullible ``rain-dance" patrons. Tornado/waterspout activity is documented right in the Tequesta site at the river in Miami, Florida, which generates detectable signals. Columbus could have used similar ``secret sacred science" previously learned from American Indians, and thereby successfully predicted an anomalous hurricane on a subsequent trip. These, and the Hawaiian volcano goddess Pelee, seem to be a mythic equivalent of electromagnetically generated signals, i.e., a metaphor for ``environmental applied physics" we detect at A.S.

  15. Envenomation by the neotropical colubrid Boiruna maculata (Boulenger, 1896: a case report Envenenamento por Colubrídeo Neotropical Boiruna maculata (Boulenger, 1896: registro de um caso

    Directory of Open Access Journals (Sweden)

    Maria Cristina dos SANTOS-COSTA

    2000-10-01

    Full Text Available This is a case report of a Boiruna maculata snake bite in a child admitted to the Hospital Municipal de Pronto Socorro de Porto Alegre, Porto Alegre, RS, Brazil. The patient was bitten on the lower left limb, and exhibited pronounced local manifestations of envenomation. She was treated with Bothrops antivenom and was discharged from the hospital five days later with marked improvement of envenomation.Este trabalho relata o envenenamento por serpente do gênero Boiruna maculata em criança admitida e posteriormente hospitalizada no Hospital Municipal de Pronto Socorro de Porto Alegre, RS, Brasil. A paciente foi mordida no membro inferior esquerdo e apresentou sinais de envenenamento local pronunciado, foi tratada como acidente botrópico e permaneceu no hospital por cinco dias, recebendo alta após melhora.

  16. Figuras zoomorfas de barro de la Edad del Hierro en la Meseta Norte

    Directory of Open Access Journals (Sweden)

    Pablo ALONSO HERNÁNDEZ

    2009-11-01

    Full Text Available RESUMEN: En el yacimiento de Las Cogotas, durante la campaña de excavaciones arqueológicas de 1986 apareció una cabeza de caballo, en barro cocido. Es de destacar su interés al igual que el de otras piezas aparecidas en las antiguas excavaciones de este yacimiento (cabeza de serpiente y bóvido. Se trata de importantes ejemplos de figuración zoomorfa en el marco de la Meseta Norte, realizados durante la Segunda Edad del Hierro.ABSTRACT: A horse's head in clay was discovered in the archaeological excavations at Las Cogotas settlement in 1986. This figure and others recovered in the excavations of the 20's (serpent and ox are remarkable in the context of zoomorphic representations of the Meseta Iron Age. They are important examples of the sculpture elaborated by Late Iron Age communitties of the Central Meseta.

  17. STEADY STATE MODELING OF THE MINIMUM CRITICAL CORE OF THE TRANSIENT REACTOR TEST FACILITY

    Energy Technology Data Exchange (ETDEWEB)

    Anthony L. Alberti; Todd S. Palmer; Javier Ortensi; Mark D. DeHart

    2016-05-01

    With the advent of next generation reactor systems and new fuel designs, the U.S. Department of Energy (DOE) has identified the need for the resumption of transient testing of nuclear fuels. The DOE has decided that the Transient Reactor Test Facility (TREAT) at Idaho National Laboratory (INL) is best suited for future testing. TREAT is a thermal neutron spectrum, air-cooled, nuclear test facility that is designed to test nuclear fuels in transient scenarios. These specific scenarios range from simple temperature transients to full fuel melt accidents. DOE has expressed a desire to develop a simulation capability that will accurately model the experiments before they are irradiated at the facility. It is the aim for this capability to have an emphasis on effective and safe operation while minimizing experimental time and cost. The multi physics platform MOOSE has been selected as the framework for this project. The goals for this work are to identify the fundamental neutronics properties of TREAT and to develop an accurate steady state model for future multiphysics transient simulations. In order to minimize computational cost, the effect of spatial homogenization and angular discretization are investigated. It was found that significant anisotropy is present in TREAT assemblies and to capture this effect, explicit modeling of cooling channels and inter-element gaps is necessary. For this modeling scheme, single element calculations at 293 K gave power distributions with a root mean square difference of 0.076% from those of reference SERPENT calculations. The minimum critical core configuration with identical gap and channel treatment at 293 K resulted in a root mean square, total core, radial power distribution 2.423% different than those of reference SERPENT solutions.

  18. Integration of the program TNXYZ in the platform SALOME

    International Nuclear Information System (INIS)

    Chaparro V, F. J.; Silva A, L.; Del Valle G, E.; Gomez T, A. M.; Vargas E, S.

    2013-10-01

    This work presents the procedure realized to integrate the code TNXYZ like a processing tool to the graphic simulation platform SALOME. The code TNXYZ solves the neutron transport equation in stationary state, for several energy groups, quantizing the angular variable by the discrete ordinates method and the space variable by nodal methods. The platform SALOME is a graphic surrounding designed for the construction, edition and simulation of mechanical models focused to the industry and contrary to other software, it allows to integrate external source codes to the surrounding, to form a complete scheme of execution, supervision, pre and post information processing. The code TNXYZ was programmed in the 90s in a Fortran compiler, but to be used at the present time the code should be actualized to the current compiler characteristics; also, in the original scheme was carried out a modularization process, that is to say, the main program was divided in sections where the code carries out important operations, with the intention of flexibility the data extraction process along its processing sequence and that can be useful in a later development of coupling. Finally, to verify the integration a fuel assembly BWR was modeled, as well as a control cell. The cross sections were obtained with the Monte Carlo Serpent code. Some results obtained with Serpent were used to verify and to begin with the validation of the code, being obtained an acceptable comparison in the infinite multiplication factor. The validation process should extend and one has planned to present in a future work. This work is part of the development of the research group formed between the Escuela Superior de Fisica y Matematicas del Instituto Politecnico Nacional (IPN) and the Instituto Nacional de Investigaciones Nucleares (ININ) in which a simulation Mexican platform of nuclear reactors is developed. (Author)

  19. Integration of the program TNXYZ in the platform SALOME; Integracion del programa TNXYZ en la plataforma SALOME

    Energy Technology Data Exchange (ETDEWEB)

    Chaparro V, F. J.; Silva A, L.; Del Valle G, E. [IPN, Escuela Superior de Fisica y Matematicas, Av. Instituto Politecnico Nacional s/n, U.P. Adolfo Lopez Mateos, Edificio 9, Col. San Pedro Zacatenco, 07738 Mexico D. F. (Mexico); Gomez T, A. M.; Vargas E, S., E-mail: javier.paquito@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    This work presents the procedure realized to integrate the code TNXYZ like a processing tool to the graphic simulation platform SALOME. The code TNXYZ solves the neutron transport equation in stationary state, for several energy groups, quantizing the angular variable by the discrete ordinates method and the space variable by nodal methods. The platform SALOME is a graphic surrounding designed for the construction, edition and simulation of mechanical models focused to the industry and contrary to other software, it allows to integrate external source codes to the surrounding, to form a complete scheme of execution, supervision, pre and post information processing. The code TNXYZ was programmed in the 90s in a Fortran compiler, but to be used at the present time the code should be actualized to the current compiler characteristics; also, in the original scheme was carried out a modularization process, that is to say, the main program was divided in sections where the code carries out important operations, with the intention of flexibility the data extraction process along its processing sequence and that can be useful in a later development of coupling. Finally, to verify the integration a fuel assembly BWR was modeled, as well as a control cell. The cross sections were obtained with the Monte Carlo Serpent code. Some results obtained with Serpent were used to verify and to begin with the validation of the code, being obtained an acceptable comparison in the infinite multiplication factor. The validation process should extend and one has planned to present in a future work. This work is part of the development of the research group formed between the Escuela Superior de Fisica y Matematicas del Instituto Politecnico Nacional (IPN) and the Instituto Nacional de Investigaciones Nucleares (ININ) in which a simulation Mexican platform of nuclear reactors is developed. (Author)

  20. Variação sazonal dos valores de bioquímica sérica de jiboias amazônicas (Boa constrictor constrictor mantidas em cativeiro

    Directory of Open Access Journals (Sweden)

    Dennis José da Silva Lima

    2012-09-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2012v25n4p165   Na região Norte do Brasil, as estações do ano não são bem definidas como acontece nas regiões Sul e Sudeste, devido ao clima equatorial quente e úmido, com um período mais chuvoso, conhecido como inverno amazônico, e um período menos chuvoso, conhecido como verão amazônico. Com esta pesquisa, objetivou-se avaliar a variação dos valores bioquímicos séricos de jiboias amazônicas correlacionadas com a sazonalidade da região. Foram realizadas análises bioquímicas séricas (AST, ALT, DHL, FA, cálcio, ácido úrico, fósforo, proteína total, albumina e globulina de 31 serpentes da espécie Boa constrictor constrictor, mantidas em cativeiro. Levando em consideração a variável sazonalidade, observou-se que oito dos dez parâmetros são maiores no inverno em comparação ao verão (proteína total, albumina, globulina, ALT, AST, FA, DHL e cálcio sendo que os valores de ALT, AST e cálcio mostraram ter diferenças estatísticas significantes no verão e inverno amazônicos, enquanto que os demais parâmetros parecem não ser influenciados pela sazonalidade. Esta foi a primeira pesquisa, em cativeiro, analisando o perfil bioquímico sérico serpentes Boa constrictor constrictor no Estado do Pará.

  1. A perturbation-based susbtep method for coupled depletion Monte-Carlo codes

    International Nuclear Information System (INIS)

    Kotlyar, Dan; Aufiero, Manuele; Shwageraus, Eugene; Fratoni, Massimiliano

    2017-01-01

    Highlights: • The GPT method allows to calculate the sensitivity coefficients to any perturbation. • Full Jacobian of sensitivities, cross sections (XS) to concentrations, may be obtained. • The time dependent XS is obtained by combining the GPT and substep methods. • The proposed GPT substep method considerably reduces the time discretization error. • No additional MC transport solutions are required within the time step. - Abstract: Coupled Monte Carlo (MC) methods are becoming widely used in reactor physics analysis and design. Many research groups therefore, developed their own coupled MC depletion codes. Typically, in such coupled code systems, neutron fluxes and cross sections are provided to the depletion module by solving a static neutron transport problem. These fluxes and cross sections are representative only of a specific time-point. In reality however, both quantities would change through the depletion time interval. Recently, Generalized Perturbation Theory (GPT) equivalent method that relies on collision history approach was implemented in Serpent MC code. This method was used here to calculate the sensitivity of each nuclide and reaction cross section due to the change in concentration of every isotope in the system. The coupling method proposed in this study also uses the substep approach, which incorporates these sensitivity coefficients to account for temporal changes in cross sections. As a result, a notable improvement in time dependent cross section behavior was obtained. The method was implemented in a wrapper script that couples Serpent with an external depletion solver. The performance of this method was compared with other existing methods. The results indicate that the proposed method requires substantially less MC transport solutions to achieve the same accuracy.

  2. Synthetic neutron camera and spectrometer in JET based on AFSI-ASCOT simulations

    Science.gov (United States)

    Sirén, P.; Varje, J.; Weisen, H.; Koskela, T.; contributors, JET

    2017-09-01

    The ASCOT Fusion Source Integrator (AFSI) has been used to calculate neutron production rates and spectra corresponding to the JET 19-channel neutron camera (KN3) and the time-of-flight spectrometer (TOFOR) as ideal diagnostics, without detector-related effects. AFSI calculates fusion product distributions in 4D, based on Monte Carlo integration from arbitrary reactant distribution functions. The distribution functions were calculated by the ASCOT Monte Carlo particle orbit following code for thermal, NBI and ICRH particle reactions. Fusion cross-sections were defined based on the Bosch-Hale model and both DD and DT reactions have been included. Neutrons generated by AFSI-ASCOT simulations have already been applied as a neutron source of the Serpent neutron transport code in ITER studies. Additionally, AFSI has been selected to be a main tool as the fusion product generator in the complete analysis calculation chain: ASCOT - AFSI - SERPENT (neutron and gamma transport Monte Carlo code) - APROS (system and power plant modelling code), which encompasses the plasma as an energy source, heat deposition in plant structures as well as cooling and balance-of-plant in DEMO applications and other reactor relevant analyses. This conference paper presents the first results and validation of the AFSI DD fusion model for different auxiliary heating scenarios (NBI, ICRH) with very different fast particle distribution functions. Both calculated quantities (production rates and spectra) have been compared with experimental data from KN3 and synthetic spectrometer data from ControlRoom code. No unexplained differences have been observed. In future work, AFSI will be extended for synthetic gamma diagnostics and additionally, AFSI will be used as part of the neutron transport calculation chain to model real diagnostics instead of ideal synthetic diagnostics for quantitative benchmarking.

  3. Marginalization and challenge: the production of knowledge and landscape in Canadian nuclear waste management policy making

    International Nuclear Information System (INIS)

    Stanley, A.E.

    2006-01-01

    Aboriginal peoples have recently become politically significant in Canadian nuclear fuel waste (NFW) management policy making. Their newfound significance comes on the heels of an important challenge to the knowledge and authority of the nuclear industry with respect to its plans for NFW lead by a number of public groups and Aboriginal peoples from across Canada, including the Serpent River First Nation. This dissertation examines the relationships between the discourses of the Serpent River First Nation (SRFN) about their experiences of the nuclear fuel chain and the discourses of the Nuclear Waste Management Organization (NWMO) about the management of NFW. Two trends are found to characterize these relationships: marginalization and challenge. The discourses of the NWMO marginalize the SRFN, excluding their experiences of the nuclear fuel chain, radioactivity, and the effects of nuclear industries from the policy making process. The discourses of the SRFN challenge the claims of the NWMO about the effects of nuclear wastes and radioactivity, as well as about the safe and beneficial development of the nuclear fuel chain. I identify discourses of 'modern risk' and 'citizenship' found in the work of the NWMO as instrumental for maintaining the nuclear industry's control over the production of knowledge about NFW and its effects and subjugating the knowledge of the SRFN. I also identify discourses of identity, oppression, and 'situated knowledge' as important challenges to the content, method and premises of the claims of the nuclear industry about the management of NFW. While I conclude that the NWMO's discourses of risk and citizenship constitute a colonial politics of exclusion, I note that their discourses are contingent on the exclusion of the experiences of the SRFN with the fuel chain. For their accounts to be coherent, the NWMO need to maintain a strategic silence on the overwhelming implication Aboriginal peoples, as a category, in the nuclear fuel chain

  4. First results for fluid dynamics, neutronics and fission product behavior in HTR applying the HTR code package (HCP) prototype

    Energy Technology Data Exchange (ETDEWEB)

    Allelein, H.-J., E-mail: h.j.allelein@fz-juelich.de [Forschungszentrum Jülich, 52425 Jülich (Germany); Institute for Reactor Safety and Reactor Technology, RWTH Aachen University, 52064 Aachen (Germany); Kasselmann, S.; Xhonneux, A.; Tantillo, F.; Trabadela, A.; Lambertz, D. [Forschungszentrum Jülich, 52425 Jülich (Germany)

    2016-09-15

    To simulate the different aspects of High Temperature Reactor (HTR) cores, a variety of specialized computer codes have been developed at Forschungszentrum Jülich (IEK-6) and Aachen University (LRST) in the last decades. In order to preserve knowledge, to overcome present limitations and to make these codes applicable to modern computer clusters, these individual programs are being integrated into a consistent code package. The so-called HTR code package (HCP) couples the related and recently applied physics models in a highly integrated manner and therefore allows to simulate phenomena with higher precision in space and time while at the same time applying state-of-the-art programming techniques and standards. This paper provides an overview of the status of the HCP and reports about first benchmark results for an HCP prototype which couples the fluid dynamics and time dependent neutronics code MGT-3D, the burn up code TNT and the fission product release code STACY. Due to the coupling of MGT-3D and TNT, a first step towards a new reactor operation and accident simulation code was made, where nuclide concentrations calculated by TNT lead to new cross sections, which are fed back into MGT-3D. Selected operation scenarios of the HTR-Module 200 concept plant and the HTTR were chosen to be simulated with the HCP prototype. The fission product release during normal operation conditions will be calculated with STACY based on a core status derived from SERPENT and MGT-3D. Comparisons will be shown against data generated by SERPENT and the legacy codes VSOP99/11, NAKURE and FRESCO-II.

  5. Toward Reanalysis of the Tight-Pitch HCLWR-PROTEUS Phase II Experiments

    Science.gov (United States)

    Perret, Grégory; Vlassopoulos, Efstathios; Hursin, Mathieu; Pautz, Andreas

    2016-03-01

    The HCLWR-Proteus Phase II experiments were conducted from 1985 to 1990 in the zero-power reactor Proteus at PSI in Switzerland. The experimental program was dedicated to the physics of high conversion light water reactors and in particular to the measurement of reactor parameters such as reaction rate traverses, spectral indices, absorber reactivity worths and void coefficients. The HCLWR experiments are especially interesting because they generated knowledge in the epithermal range of the neutron flux spectrum, for which little integral experimental data is available. In an effort to assess the interest of this experimental data to validate modern nuclear data and improve their uncertainties, a preliminary re-analysis of selected configurations was conducted with Monte-Carlo codes (MCNP6/SERPENT2) and modern nuclear data libraries (ENDF/B-VII.0, JEFF-3.1.1 and JENDL-4.0). The spectral ndices, flux spectra and sensitivity coefficients on k∞ were calculated using cell models representative of the tight-pitch measurement configurations containing 11% PuO2-UO2 fuel rods in different moderation conditions (air, water and dowtherm). Spectral index predictions using the three nuclear data libraries agreed within two standard deviations with the measured values. The only exception is the Pu-242-capture-to-Pu-239-fission ratio, which was overestimated with all libraries by more than four standard deviations, i.e. 13%, in the non-moderated configuration. In this configuration, Pu-242 captures are few since the flux spectrum in the Pu-242 capture resonance region (between 1eV and 1keV) is small making this spectral index hard to measure. Sensitivity coefficient predictions with both MCNP6 and SERPENT2 were in good agreement.

  6. Upper limits to americium concentration in large sized sodium-cooled fast reactors loaded with metallic fuel

    International Nuclear Information System (INIS)

    Zhang, Youpeng; Wallenius, Janne

    2014-01-01

    Highlights: • The americium transmutation capability of Integral Fast Reactor was investigated. • The impact from americium introduction was parameterized by applying SERPENT Monte Carlo calculations. • Higher americium content in metallic fuel leads to a power penalty, preserving consistent safety margins. - Abstract: Transient analysis of a large sized sodium-cooled reactor loaded with metallic fuel modified by different fractions of americium have been performed. Unprotected loss-of-offsite power, unprotected loss-of-flow and unprotected transient-over-power accidents were simulated with the SAS4A/SASSYS code based on the geometrical model of an IFR with power rating of 2500 MW th , using safety parameters obtained with the SERPENT Monte Carlo code. The Ti-modified austenitic D9 steel, having higher creep rupture strength, was considered as the cladding and structural material apart from the ferritic/martensitic HT9 steel. For the reference case of U–12Pu–1Am–10Zr fuel at EOEC, the margin to fuel melt during a design basis condition UTOP is about 50 K for a maximum linear rating of 30 kW/m. In order to maintain a margin of 50 K to fuel failure, the linear power rating has to be reduced by ∼3% and 6% for 2 wt.% and 3 wt.% Am introduction into the fuel respectively. Hence, an Am concentration of 2–3 wt.% in the fuel would lead to a power penalty of 3–6%, permitting a consumption rate of 3.0–5.1 kg Am/TW h th . This consumption rate is significantly higher than the one previously obtained for oxide fuelled SFRs

  7. Avaliação da resposta inflamatória hematológica em cascavéis (Crotalus durissus Linnaeus, 1758 inoculadas com BCG Assessment of blood inflammatory response in BCG stimulated rattlesnakes (Crotalus durissus Linnaeus, 1758

    Directory of Open Access Journals (Sweden)

    Wellington Bandeira da Silva

    2009-12-01

    Full Text Available A criação de serpentes peçonhentas em cativeiro para produção de soros antipeçonhas possui crescente importância para a saúde pública devido ao aumento do número de notificações de acidentes ofídicos a cada ano no Brasil. Iniciado no século XX, ainda hoje essa atividade apresenta alguns desafios como a instalação de doenças no plantel. O hemograma é um exame de triagem clínica que auxilia no diagnóstico de diversas moléstias que acometem diferentes espécies de animais, no entanto ainda pouco estudado em serpentes. A caracterização das alterações hematológicas em cascavéis inoculadas experimentalmente com BCG pode servir de base na utilização deste exame no auxílio ao diagnóstico de infecções bacterianas na espécie. Dessa forma, foram realizados exames hematológicos em 10 serpentes da espécie Crotalus durissus pertencentes ao plantel da Divisão de Herpetologia do Instituto Vital Brazil. Os animais foram divididos em dois grupos (Grupos 1 e 2, homogêneos entre si em relação ao peso e proporção sexual. Os dois grupos foram inoculados com BCG e submetidos à coleta de sangue antes da inoculação e em três momentos pós-inoculação (3º, 5º, e 7º dias para o Grupo 1 e 11º, 17º e 21º dias para o Grupo 2. O hemograma foi realizado por método semidireto pela utilização de líquido de Natt e Herrick e as lâminas foram coradas pelo Giemsa. Observou-se anemia discreta, com redução dos valores de concentração de hemoglobina corpuscular média e da hemoglobina globular média no Grupo 1 que foi relacionada à doença inflamatória. A trombocitopenia observada no Grupo 2 sugeriu a atuação deste tipo celular em processos inflamatórios. Um único animal do Grupo 1 apresentou granulocitose e alguns animais apresentaram discreta azurofilia. Observaram-se alterações morfológicas nos leucócitos. Os granulócitos apresentaram granulações grosseiras e os azurófilos apresentaram aumento de tamanho e

  8. Fragmentation of deuteronated aromatic derivatives: The role of ion-neutral complexes

    Science.gov (United States)

    Harrison, Alex G.; Wang, Jian-Yao

    1997-01-01

    The low-energy collision-induced dissociation reactions of the MD+ ions of a number of alkyl phenyl ethers, alkylbenzenes, acetophenones and benzaldehyde have been studied as a function of collision energy to establish qualitatively the dependence of the fragmentation reactions observed on internal energy. Deuteronated alkyl phenyl ethers (ROC6H5·D+, R = C3H7, C4H9) fragment at low collision energies to form C6H5OHD+ + (R-H), the thermochemically favoured products; with increasing collision energy (and, hence, internal energy) formation of the alkyl ion R+ increases significantly in importance. Deuteronated alkylbenzenes (RC6H5, RC6H4R', R = C2H5, C3H7) similarly form the deuteronated benzene (the thermochemically favoured product) at low collision energies with formation of the alkyl ion R+ being observed at higher collision energies. The results for both systems are consistent with a fragmentation mechanism involving initial formation of an R+/aromatic ion/neutral complex. At low internal energies proton transfer occurs within this complex to form an ion/neutral complex consisting of the deuteronated aromatic and a neutral olefin; this complex fragments to the thermochemically favoured products. Since the transition state leading to these products is a "tight" transition state involving loss of rotational degrees of freedom, the proton transfer reaction is unfavourable entropically with respect to simple dissociation of the R+/aromatic complex to R+ + ArD. Consequently, these products increase in importance as the internal energy is increased. The fragmentation of deuteronated aromatic carbonyl compounds can also be rationalized by similar mechanisms involving the intermediacy of ion/neutral complexes. Deuteronated acetophenone forms only CH3CO+ at all collision energies; this is both the thermochemically and entropically favoured product. However, deuteronated p-aminoacetophenone forms deuteronated aniline, the thermochemically favoured product at low collision

  9. Aspectos morfológicos e ultraestruturais de células sanguíneas de Crotalus durissus terrificus

    Directory of Open Access Journals (Sweden)

    Lívia M. Kindlovits

    Full Text Available RESUMO: A avaliação hematológica, de importância comprovada como um meio auxiliar de diagnóstico ao clínico de pequenos animais domésticos, vem se tornando comum em animais selvagens não apenas para a clínica, mas para a avaliação do manejo e como estudo auxiliar para a fisiologia das várias espécies. Tendo em vista o aumento da demanda para a produção de várias drogas de importância farmacêutica, a criação de serpentes peçonhentas vem se tornando comum a ponto destes animais já serem reconhecidos como sendo de produção. O conhecimento do manejo e da clínica destes animais ainda é escasso e a mortalidade é elevada nos criatórios, tornando urgente a ampliação destes. Embora alguns estudos hematológicos já tenham sido realizados em cascavéis (Crotalus durissus os dados analisados ainda são insipientes, notadamente em relação à caracterização das células do sangue e poucos estudos em microscopia eletrônica foram realizados em serpentes. Com o objetivo de caracterizar as células sanguíneas morfologicamente, sob microscopia óptica e ultraestrutural, foram coletadas amostras de sangue de 52 de indivíduos da subespécie Crotalus durissus terrificus para a realização de esfregaços sanguíneos e avaliação ultraestrutural. Concluiu-se que a coloração hematológica de Giemsa permite a avaliação morfológica e a diferenciação das células sanguíneas em serpentes assim como a visualização de hemoparasitos. A avaliação ultraestrutural permite evidenciar as organelas celulares e a diferenciação entre as células, inclusive entre os tipos leucocitários, porém ainda são necessários outros estudos para que seja elucidada a hipótese da existência dos eosinófilos na espécie estudada assim como é necessária melhor caracterização dos grânulos dos azurófilos para que se confirme uma possível diferença entre os monócitos típicos e os azurófilos.

  10. Extension of the reactor dynamics code MGT-3D for pebblebed and blocktype high-temperature-reactors

    International Nuclear Information System (INIS)

    Shi, Dunfu

    2015-01-01

    The High Temperature Gas cooled Reactor (HTGR) is an improved, gas cooled nuclear reactor. It was chosen as one of the candidates of generation IV nuclear plants [1]. The reactor can be shut down automatically because of the negative reactivity feedback due to the temperature's increasing in designed accidents. It is graphite moderated and Helium cooled. The residual heat can be transferred out of the reactor core by inactive ways as conduction, convection, and thermal radiation during the accident. In such a way, a fuel temperature does not go beyond a limit at which major fission product release begins. In this thesis, the coupled neutronics and fluid mechanics code MGT-3D used for the steady state and time-dependent simulation of HTGRs, is enhanced and validated [2]. The fluid mechanics part is validated by SANA experiments in steady state cases as well as transient cases. The fuel temperature calculation is optimized by solving the heat conduction equation of the coated particles. It is applied in the steady state and transient simulation of PBMR, and the results are compared to the simulation with the old overheating model. New approaches to calculate the temperature profile of the fuel element of block-type HTGRs, and the calculation of the homogeneous conductivity of composite materials are introduced. With these new developments, MGT-3D is able to simulate block-type HTGRs as well. This extended MGT-3D is used to simulate a cuboid ceramic block heating experiment in the NACOK-II facility. The extended MGT-3D is also applied to LOFC and DLOFC simulation of GT-MHR. It is a fluid mechanics calculation with a given heat source. This calculation result of MGT-3D is verified with the calculation results of other codes. The design of the Japanese HTTR is introduced. The deterministic simulation of the LOFC experiment of HTTR is conducted with the Monte-Carlo code Serpent and MGT-3D, which is the LOFC Project organized by OECD/NEA [3]. With Serpent the burnup

  11. Comparison of wildlife and captivity rattlesnakes (Crotalus durissus terrificus microbiota Comparação da microbiota de cascavéis (Crotalus durissus terrificus de vida-livre e cativeiro

    Directory of Open Access Journals (Sweden)

    Rui S. Ferreira Junior

    2009-12-01

    Full Text Available The study evaluated and compared the aerobic microbiota from the oral cavity, cloaca and venom of Crotalus durissus terrificus snakes, recently caught from the wild and kept under quarantine (WQ, individual captivity (IC and collective captivity (CC. Antimicrobial drug effectiveness on isolated agents also was assayed. From group I, II and III were isolated, respectively, 29 (63.04%, 38 (90.48% and 21 (42.86% microorganisms from the cloaca; 15 (32.61%, 3 (7.14% and 25 (51.02% microorganisms from the oral cavity; and, 2 (4.35%, 1 (2.38% and 3 (6.12% microorganisms from venom. The most frequent bacteria were Pseudomonas aeruginosa, Proteus vulgaris and Morganella morganii, with sensitivity to amikacin, gentamicin, norfloxacin, sulfazotrin and tobramycin. Snakes kept in semi-open captivity exhibited the fewest microorganisms in oral cavities, perhaps due to the environment in captivity, with different temperature gradients, running water, absence of daily handling, circulating air, possibility of moving around, daily cleaning, and sunlight access.Este estudo avaliou e comparou a microflora aeróbica da cavidade oral, cloaca e veneno de serpentes Crotalus durissus terrificus recém-capturadas da natureza e mantidas sob quarentena (WQ, mantidas em cativeiro coletivo (CC e em cativeiro individual (IC. A eficácia de drogas antimicrobianas de agentes isolados foi também avaliada. Foram isolados microorganismos dos grupos I, II e III respectivamente: 29 (63.04%, 38 (90.48% e 21 (42.86% da cloaca; 15 (32.61%, 3 (7.14% e 25 (51.02% da cavidade oral, e finalmente 2 (4.35%, 1 (2.38% e 3 (6.12% do veneno. As bactérias mais frequentes foram Pseudomonas aeruginosa, Proteus vulgaris e Morganella morganii, com sensibilidade para amikacina, gentamicina, norfloxacina, sulfazotrina e tobramicina. Serpentes mantidas no cativeiro semi-aberto mostraram menor número de agentes infecciosos em cavidade oral, talvez devido ao ambiente de cativeiro com diferentes

  12. Analysis of a Spanish energy scenario with Generation IV nuclear reactors

    International Nuclear Information System (INIS)

    Ochoa, Raquel; Jimenez, Gonzalo; Perez-Martin, Sara

    2013-01-01

    Highlights: • Spanish energy scenario for the hypothetical deployment of Gen-IV SFR reactors. • Availability of national resources is assessed, considering SFR’s breeding. • An assessment of the impact of transmuting MA on the final repository. • SERPENT code with own pre- and post-processing tools were employed. • The employed SFR core design is based on the specifications of the CP-ESFR. - Abstract: The advantages of fast-spectrum reactors consist not only of an efficient use of fuel through the breeding of fissile material and the use of natural or depleted uranium, but also of the potential reduction of the amount of actinides such as americium and neptunium contained in the irradiated fuel. The first aspect means a guaranteed future nuclear fuel supply. The second fact is key for high-level radioactive waste management, because these elements are the main responsible for the radioactivity of the irradiated fuel in the long term. The present study aims to analyze the hypothetical deployment of a Gen-IV Sodium Fast Reactor (SFR) fleet in Spain. A nuclear fleet of fast reactors would enable a fuel cycle strategy different than the open cycle, currently adopted by most of the countries with nuclear power. A transition from the current Gen-II to Gen-IV fleet is envisaged through an intermediate deployment of Gen-III reactors. Fuel reprocessing from the Gen-II and Gen-III Light Water Reactors (LWR) has been considered. In the so-called advanced fuel cycle, the reprocessed fuel used to produce energy will breed new fissile fuel and transmute minor actinides at the same time. A reference case scenario has been postulated and further sensitivity studies have been performed to analyze the impact of the different parameters on the required reactor fleet. The potential capability of Spain to supply the required fleet for the reference scenario using national resources has been verified. Finally, some consequences on irradiated final fuel inventory are assessed

  13. The origin of snakes: revealing the ecology, behavior, and evolutionary history of early snakes using genomics, phenomics, and the fossil record.

    Science.gov (United States)

    Hsiang, Allison Y; Field, Daniel J; Webster, Timothy H; Behlke, Adam D B; Davis, Matthew B; Racicot, Rachel A; Gauthier, Jacques A

    2015-05-20

    The highly derived morphology and astounding diversity of snakes has long inspired debate regarding the ecological and evolutionary origin of both the snake total-group (Pan-Serpentes) and crown snakes (Serpentes). Although speculation abounds on the ecology, behavior, and provenance of the earliest snakes, a rigorous, clade-wide analysis of snake origins has yet to be attempted, in part due to a dearth of adequate paleontological data on early stem snakes. Here, we present the first comprehensive analytical reconstruction of the ancestor of crown snakes and the ancestor of the snake total-group, as inferred using multiple methods of ancestral state reconstruction. We use a combined-data approach that includes new information from the fossil record on extinct crown snakes, new data on the anatomy of the stem snakes Najash rionegrina, Dinilysia patagonica, and Coniophis precedens, and a deeper understanding of the distribution of phenotypic apomorphies among the major clades of fossil and Recent snakes. Additionally, we infer time-calibrated phylogenies using both new 'tip-dating' and traditional node-based approaches, providing new insights on temporal patterns in the early evolutionary history of snakes. Comprehensive ancestral state reconstructions reveal that both the ancestor of crown snakes and the ancestor of total-group snakes were nocturnal, widely foraging, non-constricting stealth hunters. They likely consumed soft-bodied vertebrate and invertebrate prey that was subequal to head size, and occupied terrestrial settings in warm, well-watered, and well-vegetated environments. The snake total-group - approximated by the Coniophis node - is inferred to have originated on land during the middle Early Cretaceous (~128.5 Ma), with the crown-group following about 20 million years later, during the Albian stage. Our inferred divergence dates provide strong evidence for a major radiation of henophidian snake diversity in the wake of the Cretaceous-Paleogene (K

  14. Feasibility to convert an advanced PWR from UO2 to a mixed U/ThO2 core – Part I: Parametric studies

    International Nuclear Information System (INIS)

    Maiorino, Jose R.; Stefani, Giovanni Laranjo; Moreira, João M.L.; Rossi, Pedro C.R.; Santos, Thiago A.

    2017-01-01

    Highlights: • Neutronics calculation using SERPENT code. • Conversion of an advanced PWR from a UO 2 to (U-Th)O 2 core. • AP 1000-advanced PWR. • Parametric studies to define a converted core. • Demonstration of the feasibility to convert the AP 1000 by using mixed uranium thorium oxide fuel with advantages. - Abstract: This work presents the neutronics and thermal hydraulics feasibility to convert the UO 2 core of the Westinghouse AP1000 in a (U-Th)O 2 core by performing a parametric study varying the type of geometry of the pins in fuel elements, using the heterogeneous seed blanket concept and the homogeneous concept. In the parametric study, all geometry and materials for the burnable poison were kept the same as the AP 1000, and the only variable was the fuel pin material, in which we use several mass proportion of uranium and thorium but keeping the enrichment in 235 U, as LEU (20 w/o). The neutronics calculations were made by SERPENT code, and to validate the thermal limits we used a homemade code. The optimization criteria were to maximize the 233 U, and conversion factor, and minimize the plutonium production. The results obtained showed that the homogeneous concept with three different mass proportion zones, the first containing (32% UO 2 -68%ThO 2 ); the second with (24% UO 2 -76% ThO 2 ), and the third with (20% UO 2 -80% ThO 2 ), using 235 U LEU (20 w/o), and corresponding with the 3 enrichment zones of the AP 1000 (4.45 w/o; 3.40 w/o; 2.35 w/o), satisfies the optimization criteria as well as attending all thermal constrain. The concept showed advantages compared with the original UO 2 core, such a lower power density, and keeping the same 18 months of cycle a reduction of B-10 concentration at the soluble poison as well as eliminating in the integral boron poison coated (IFBA).

  15. Cost optimization of ADS design: Comparative study of externally driven heterogeneous and homogeneous two-zone subcritical reactor systems

    International Nuclear Information System (INIS)

    Gulik, Volodymyr; Tkaczyk, Alan H.

    2014-01-01

    Highlights: • The optimization of two-zone homogeneous subcritical systems has been performed. • A Serpent model for two-zone heterogeneous subcritical systems has been developed. • The optimization of two-zone heterogeneous subcritical systems has been carried out. • Economically optimal core composition of two-zone subcritical system was found. • The neutron spectra of the heterogeneous subcritical systems have been obtained. - Abstract: Subcritical systems driven by external neutron sources, commonly known as Accelerator-Driven System (ADS), are one type of advanced nuclear reactor exhibiting attractive characteristics, distinguished from the traditional critical systems by their intrinsic safety features. In addition, an ADS can be used for the transmutation of the nuclear waste, accumulated during the operation of existing reactors. The optimization of a subcritical nuclear reactor in terms of materials (fuel content, coolant, etc.), geometrical, and economical parameters is a crucial step in the process of their design and construction. This article describes the optimization modeling performed for homogeneous and heterogeneous two-zone subcritical systems in terms of geometry of the fuel zones. Economical assessment was also carried out for the costs of the fuel in the core of the system. Optimization modeling was performed with the Serpent-1.1.18 Monte Carlo code. The model of a two-zone subcritical system with a fast inner and a thermal gas-cooled graphite-moderated outer zone was developed, simulated, and analyzed. The optimal value for the pitch of fuel elements in the thermal outer zone was investigated from the viewpoint of the cost of subcritical system. As the main goal of ADS development is nuclear waste transmutation, neutron spectra for both fast and thermal zones were obtained for different system configurations. The results of optimization modeling of homogeneous and heterogeneous two-zone subcritical systems show that an optimal

  16. The complete mitochondrial genome of a gecko and the phylogeneticposition of the Middle Eastern teratoscincus keyserlingii

    Energy Technology Data Exchange (ETDEWEB)

    Macey, J. Robert; Fong, Jonathan J.; Kuehl, Jennifer V.; Shafiei,Soheila; Ananjeva, Natalia B.; Papenfuss, Theodore J.; Boore, Jeffrey L.

    2005-04-22

    Sqamate reptiles are traditionally divided into six groups: Iguania, Anguimorpha, Scincomorpha, Gekkota (these four are lizards), Serpentes (snakes), and Amphisbaenia (the so-called worm lizards). Currently there are complete mitochondrial genomes from two representatives of the Iguania (Janke et al., 2001; Kumazawa, 2004), three from the Anguimorpha (Kumazawa, 2004; Kumazawa and Endo, 2004), two from the Scincomorpha (Kumazawa and Nishida, 1999; Kumazawa, 2004), two from Serpentes (Kumazawa et al., 1998; Kumazawa, 2004) and 12 from Amphisbaenia (Macey et al., 2004). The only traditional group of Squamata from which a complete mitochondrial genome has not been sequenced is the Gekkota. Here we report the complete mitochondrial genome of Teratoscincus keyserlingii, a Middle Eastern representative of the Gekkota. The gekkonid lizard genus Teratoscincus is distributed throughout the deserts of central and southwest Asia as shown in figure 1, with five species currently recognized (Macey et al. 1997a, 1999b). Included in this figure are the positions of mountain ranges discussed in the text; see also figure 1 in Macey et al. (1999b). Two species, T. bedriagai and T. microlepis, are restricted to Southwest Asia south of the Kopet Dagh and Hindu Kush in Iran, Afghanistan, and Pakistan (Anderson, 1999). Two species are found in the deserts of western China and Mongolia, with T. przewalskii occurring in the Taklimakan and lowland Gobi deserts, and T. roborowskii restricted to the Turpan Depression. The fifth species, T. scincus, is sometimes considered to be restricted to the Caspian Basin in Kazakhstan, Kyrgyzistan, Tadjikistan, Turkmenistan and Uzbekistan. Alternatively, Teratoscincus populations in Southwest Asia, primarily on the Iranian Plateau, situated directly north of the Arabian Plate, are sometimes considered to be a subspecies of T. scincus or, otherwise, to constitute a sixth species, T. keyserlingii. Macey et al. (1999b) assessed the phylogenetic

  17. Study of the hydrodynamic of groundwater karst system of Laraos and Alis, upper basin of the Canete river using environmental isotopes

    International Nuclear Information System (INIS)

    Valencia, Jacinto; Mamani, Enoc; Magina, Jose

    2014-01-01

    In this study, seven water samples have been characterized, collected from the upper Canete river micro-basins Laraos and Alis. They were analyzed by Oxygen-18 (δ18O), deuterium (δ2H) and radioactive tritium (3H) using the technique of laser spectrometry and characterized in order to establish the recharge-discharge relationship karst system under study, formed by the dissolution of limestone from the Cretaceous age formation Jumasha, and forming watertight groundwater that by connection and hydraulic gradient of fractures discharge into springs. The interpretation of the isotopic analysis performed according to the diagram δ18O/δ2H indicates that the springs are originated from infiltrating rainwater into the karst system due to the structural design and make the connection between micro-basins. Groundwater has a different dynamic, and to a lesser extent, receives contributions from waters lagoons, this fact makes them vulnerable to contamination. In the karst hydrogeological system, groundwater from micro-basins has a dynamic part of water with a long residence time with 1.8 units of tritium (RC-7) and another water dynamic of short residence time of 3 and 3.2 tritium units (RC-4, RC-5, RC-6). (authors).

  18. Using MMPI-2-RF Correlates to Elucidate the PCL-R and Its Four Facets in a Sample of Male Forensic Psychiatric Patients.

    Science.gov (United States)

    Klein Haneveld, Evelyn; Kamphuis, Jan H; Smid, Wineke; Forbey, Johnathan D

    2017-01-01

    This study documents the associations between the MMPI-2-RF (Ben-Porath & Tellegen, 2008 ) scale scores and the Psychopathy Checklist Revised (PCL-R; Hare, 2003 ) facet scores in a forensic psychiatric sample. Objectives were to determine how the MMPI-2-RF scales might enhance substantive understanding of the nature of the 4 PCL-R facets and to discern possible implications for the treatment of psychopathic patients. A sample of 127 male forensic psychiatric offenders admitted to a Dutch forensic psychiatric hospital completed the PCL-R and the MMPI-2. Exploratory stepwise regression analyses assessed the prediction of the PCL-R total and its facet scores from MMPI-2-RF scales at its 3 hierarchical levels. Conceptually meaningful results emerged at each level of the MMPI-2-RF hierarchy, including several consistent differences between predictor sets across the facets. Interestingly, ideas of persecution (RC6) was a specific predictor of PCL-R Facet 2, a facet noted for its association with treatment failure. Results are compared and contrasted to the extant body of empirical work to date, and some tentative clinical implications are offered.

  19. Study of energy dependence of a extrapolation chamber in low energy X-rays beams

    International Nuclear Information System (INIS)

    Bastos, Fernanda M.; Silva, Teogenes A. da

    2014-01-01

    This work was with the main objective to study the energy dependence of extrapolation chamber in low energy X-rays to determine the value of the uncertainty associated with the variation of the incident radiation energy in the measures in which it is used. For studying the dependence of energy, were conducted comparative ionization current measurements between the extrapolation chamber and two ionization chambers: a chamber mammography, RC6M model, Radcal with energy dependence less than 5% and a 2575 model radioprotection chamber NE Technology; both chambers have very thin windows, allowing its application in low power beams. Measurements were made at four different depths of 1.0 to 4.0 mm extrapolation chamber, 1.0 mm interval, for each reference radiation. The study showed that there is a variable energy dependence on the volume of the extrapolation chamber. In other analysis, it is concluded that the energy dependence of extrapolation chamber becomes smaller when using the slope of the ionization current versus depth for the different radiation reference; this shows that the extrapolation technique, used for the absorbed dose calculation, reduces the uncertainty associated with the influence of the response variation with energy radiation

  20. Reaction of Tris(cyclopentadienyl)uranium compounds with amines, azides, and related ligands

    International Nuclear Information System (INIS)

    Rosen, R.K.

    1989-12-01

    The trivalent uranium compound, (MeC 5 H 4 ) 3 U(thf), serves as a one- or two-electron reducing agent towards azides, RN 3 . These reactions produce either the uranium(IV) azide, (MeC 5 H 4 ) 3 UN 3 , or uranium(V) imides, (MeC 5 H 4 ) 3 UNR. The role of steric and electronic effects upon this reaction has been investigated using several series of azides. For Me 3 XN 3 , the imides are produced when X = C or Si, both products are formed when X = Ge, and the azide is produced when X = Sn. For Ph 3 XN 3 , the azide is produced when X = C or Sn. For Ph 3-x CH 3 N 3 , the imide is produced when x = 2 and both compounds are produced when x = 1. For substituted phenylazides, RC 6 H 4 N 3 , only the imides are produced. The magnetic properties of uranium diimides, [(MeC 5 H 4 ) 3 U] 2 (μ-NRN), were investigated. Several uranium(III) amines, (MeC 5 H 4 ) 3 U(NH 2 R), were produced from (MeC 5 H 4 ) 3 U(thf) and RNH 2 , and NH 3 was found to be a better ligand towards (MeC 5 H 4 ) 3 U than is PMe 3

  1. Potentiometric investigation into complexing of Pr,Eu,Yb with new β-diketones containing oxygen atom in fluorinated radical

    International Nuclear Information System (INIS)

    Gritsenko, T.V.; Lozinskij, M.O.; Panyushkin, V.T.; Fialkov, Yu.A.; Berenblit, V.V.; AN Ukrainskoj SSR, Kiev. Inst. Organicheskoj Khimii)

    1983-01-01

    Potentiometric method in the aqueous-methanol media at 25 deg and ionic torce of 0.15 (NaCl) has been used to determine the constants of acidic dissociation of the next β-diketones; Rsub(F)-CO-CHsub(2)-CO-R, where R=-C 6 H 5 , Rsub(F) C 3 F 7 OCF(CF 3 ) - (1), CF 3 O(CF 2 ) 3 OCF(CF 3 ) - (2), CF 3 O(CF 2 O) 4 CF 2 - (3), CF 3 O(CF 2 ) 2 - (4) and R=-C 4 H 3 S, Rsub(F) CF 3 O(CF 2 ) 3 OCF(CF 3 ) - (5), CF 3 O(CF 2 O) 4 CF 2 - (6). Synthesis of the 1-3, 5, 6 is described. Stability constants of Pr 3+ , Eu 3+ , Yb 3+ with 1-6 are calculated. Stability of the complexes for the each β-diketone increases in Pr-Eu-Yb series. Correlation between stability of the chelates and acidic properties of the β-diketonates is traced for the complexes of one metal with different ligands. Thus, the acidic properties of the β-diketones increase in the 1, 6-4 series; stability of their complexes with rare earths decreases in such order

  2. Spin–Orbit Alignment of Exoplanet Systems: Ensemble Analysis Using Asteroseismology

    DEFF Research Database (Denmark)

    Campante, T. L.; Lund, M. N.; Kuszlewicz, James S.

    2016-01-01

    seems to be well aligned with the stellar spin axis ( ##IMG## [http://ej.iop.org/images/0004-637X/819/1/85/apj522683ieqn2.gif] $psi =12rc. 6_-11.0^+6.7$ ). While the latter result is in apparent contradiction with a statement made previously in the literature that the multi-transiting system Kepler-25...... observed with NASA’s Kepler satellite. Our results for i s are consistent with alignment at the 2 σ level for all stars in the sample, meaning that the system surrounding the red-giant star Kepler-56 remains as the only unambiguous misaligned multiple-planet system detected to date. The availability...... of a measurement of the projected spin–orbit angle λ for two of the systems allows us to estimate ψ . We find that the orbit of the hot Jupiter HAT-P-7b is likely to be retrograde ( ##IMG## [http://ej.iop.org/images/0004-637X/819/1/85/apj522683ieqn1.gif] $psi =116rc. 4_-14.7^+30.2$ ), whereas that of Kepler-25c...

  3. Study of advanced rotary combustion engines for commuter aircraft

    Science.gov (United States)

    Berkowitz, M.; Jones, C.; Myers, D.

    1983-01-01

    Performance, weight, size, and maintenance data for advanced rotary aircraft engines suitable for comparative commuter aircraft system evaluation studies of alternate engine candidates are provided. These are turbocharged, turbocompounded, direct injected, stratified charge rotary engines. Hypothetical engines were defined (an RC4-74 at 895 kW and an RC6-87 at 1490 kW) based on the technologies and design approaches used in the highly advanced engine of a study of advanced general aviation rotary engines. The data covers the size range of shaft power from 597 kW (800 hp) to 1865 kW (2500 hp) and is in the form of drawings, tables, curves and written text. These include data on internal geometry and configuration, installation information, turbocharging and turbocompounding arrangements, design features and technologies, engine cooling, fuels, scaling for weight size BSFC and heat rejection for varying horsepower, engine operating and performance data, and TBO and maintenance requirements. The basic combustion system was developed and demonstrated; however the projected power densities and performance efficiencies require increases in engine internal pressures, thermal loading, and rotative speed.

  4. Technical Capability Upgrades to the NASA Langley Research Center 6 ft. by 6 ft. Thermal Vacuum Chamber

    Science.gov (United States)

    Thornblom, Mark N.; Beverly, Joshua; O'Connell, Joseph J.; Mau, Johnny C.; Duncan, Dwight L.

    2014-01-01

    The 6 ft. by 6 ft. thermal vacuum chamber (TVAC), housed in Building 1250 at the NASA Langley Research Center (LaRC), and managed by the Systems Integration and Test Branch within the Engineering Directorate, has undergone several significant modifications to increase testing capability, safety, and quality of measurements of articles under environmental test. Significant modifications include: a new nitrogen thermal conditioning unit for controlling shroud temperatures from -150degC to +150degC; two horizontal auxiliary cold plates for independent temperature control from -150degC to +200degC; a suite of contamination monitoring sensors for outgassing measurements and species identification; signal and power feed-throughs; new pressure gauges; and a new data acquisition and control commanding system including safety interlocks. This presentation will provide a general overview of the LaRC 6 ft. by 6 ft. TVAC chamber, an overview of the new technical capabilities, and illustrate each upgrade in detail, in terms of mechanical design and predicted performance. Additionally, an overview of the scope of tests currently being performed in the chamber will be documented, and sensor plots from tests will be provided to show chamber temperature and pressure performance with actual flight hardware under test.

  5. Demonologie in die Nuwe-Testamentiese tydvak

    Directory of Open Access Journals (Sweden)

    A. G. van Aarde

    1986-01-01

    Full Text Available Demonology in New Testament times Modem demonology has become a cult just as it had been in mediaeval times. But there is a difference. Then people opposed the Devil; now people believe in the Devil. This paper argues that modem demonology is an escapism of reality and in direct contrast to the New Testament's message. The thesis is debated against the background of a discussion of demonology in New Testament times. In this discussion it is indicated how the face of evil has changed from Old Testament times up to the New Testament period. Evil has become an extraterrestrial figure, symbol and power. As the personification of the prince of evil, the Devil is inter alia identified with the mythological serpent in a lost paradise and is defeated at the realization of God's messianic kingdom in Jesus Christ, the prince of light. The New Testament proclaims that salvation means that man determines to exist as man of God before evil made man his slave.

  6. Impact of nuclear data uncertainty on safety calculations for spent nuclear fuel geological disposal

    Directory of Open Access Journals (Sweden)

    Herrero J.J.

    2017-01-01

    Full Text Available In the design of a spent nuclear fuel disposal system, one necessary condition is to show that the configuration remains subcritical at time of emplacement but also during long periods covering up to 1,000,000 years. In the context of criticality safety applying burn-up credit, k-eff eigenvalue calculations are affected by nuclear data uncertainty mainly in the burnup calculations simulating reactor operation and in the criticality calculation for the disposal canister loaded with the spent fuel assemblies. The impact of nuclear data uncertainty should be included in the k-eff value estimation to enforce safety. Estimations of the uncertainty in the discharge compositions from the CASMO5 burn-up calculation phase are employed in the final MCNP6 criticality computations for the intact canister configuration; in between, SERPENT2 is employed to get the spent fuel composition along the decay periods. In this paper, nuclear data uncertainty was propagated by Monte Carlo sampling in the burn-up, decay and criticality calculation phases and representative values for fuel operated in a Swiss PWR plant will be presented as an estimation of its impact.

  7. Carbon Isotope Systematics in Mineral-Catalyzed Hydrothermal Organic Synthesis Processes at High Temperature and Pressures

    Science.gov (United States)

    Fu, Qi; Socki, R. A.; Niles, Paul B.

    2011-01-01

    Observation of methane in the Martian atmosphere has been reported by different detection techniques. Reduction of CO2 and/or CO during serpentization by mineral surface catalyzed Fischer-Tropsch Type (FTT) synthesis may be one possible process responsible for methane generation on Mars. With the evidence a recent study has discovered for serpentinization in deeply buried carbon rich sediments, and more showing extensive water-rock interaction in Martian history, it seems likely that abiotic methane generation via serpentinization reactions may have been common on Mars. Experiments involving mineral-catalyzed hydrothermal organic synthesis processes were conducted at 750 C and 5.5 Kbars. Alkanes, alcohols and carboxylic acids were identified as organic compounds. No "isotopic reversal" of delta C-13 values was observed for alkanes or carboxylic acids, suggesting a different reaction pathway than polymerization. Alcohols were proposed as intermediaries formed on mineral surfaces at experimental conditions. Carbon isotope data were used in this study to unravel the reaction pathways of abiotic formation of organic compounds in hydrothermal systems at high temperatures and pressures. They are instrumental in constraining the origin and evolution history of organic compounds on Mars and other planets.

  8. Comparative evaluation of fuel temperature coefficient of standard and CANFLEX fuels in CANDU 6

    International Nuclear Information System (INIS)

    Kim, Woosong; Hartant, Donny; Kim, Yonghee

    2012-01-01

    The fuel temperature reactivity coefficient (FTC) of CANDU 6 has become a concerning issue. The FTC was found to be slightly positive for the operating condition of CANDU 6. Since CANDU 6 has unique fuel arrangement and very soft neutron spectrum, its Doppler reactivity feedback of U 238 is rather weak. The upscattering by oxygen in fuel and Pu 239 buildup with fuel depletion are responsible for the positive FTC value at high temperature. In this study, FTC of both standard CANDU and CANFLEX fuel lattice are re evaluated. A Monte Carlo code Serpent2 was chosen as the analysis tool because of its high calculational speed and it can account for the thermal motion of heavy nuclides in fuel by using the Doppler Broadening Rejection Correction (DBRC) method. It was reported that the fuel Doppler effect is noticeably enhanced by accounting the target thermal motion. Recently, it was found that the FTC of the CANDU 6 standard fuel is noticeably enhanced by the DBRC

  9. Radiation shielding properties of high performance concrete reinforced with basalt fibers infused with natural and enriched boron

    Energy Technology Data Exchange (ETDEWEB)

    Zorla, Eyüp; Ipbüker, Cagatay [University of Tartu, Institute of Physics (Estonia); Biland, Alex [US Basalt Corp., Houston (United States); Kiisk, Madis [University of Tartu, Institute of Physics (Estonia); Kovaljov, Sergei [OÜ Basaltest, Tartu (Estonia); Tkaczyk, Alan H. [University of Tartu, Institute of Physics (Estonia); Gulik, Volodymyr, E-mail: volodymyr.gulik@gmail.com [Institute for Safety Problems of Nuclear Power Plants, Lysogirska 12, of. 201, 03028 Kyiv (Ukraine)

    2017-03-15

    Highlights: • Basalt fiber infused with natural and enriched boron in varying proportions. • Gamma-ray attenuation remains stable with addition of basalt-boron fiber. • Improvement in neutron shielding for nuclear facilities producing fast fission spectrum. • Basalt-boron fiber could decrease the shielding thickness in thermal spectrum reactors. - Abstract: The importance of radiation shielding is increasing in parallel with the expansion of the application areas of nuclear technologies. This study investigates the radiation shielding properties of two types of high strength concrete reinforced with basalt fibers infused with 12–20% boron oxide, containing varying fractions of natural and enriched boron. The gamma-ray shielding characteristics are analyzed with the help of the WinXCom, whereas the neutron shielding characteristics are modeled and computed by Monte Carlo Serpent code. For gamma-ray shielding, the attenuation coefficients of the studied samples do not display any significant variation due to the addition of basalt-boron fibers at any mixing proportion. For neutron shielding, the addition of basalt-boron fiber has negligible effects in the case of very fast neutrons (14 MeV), but it could considerably improve the neutron shielding of concrete for nuclear facilities producing a fast fission spectrum (e.g. with reactors as BN-800, FBTR) and thermal neutron spectrum (Light Water Reactors (LWR)). It was also found that basalt-boron fiber could decrease the thickness of radiation shielding material in thermal spectrum reactors.

  10. Canadian experience with uranium tailings disposal

    International Nuclear Information System (INIS)

    Culver, K.B.

    1982-06-01

    During the first years of uranium production in Canada uranium tailings were discharged directly into valleys or lakes near the mill. Treatment with barium chloride to precipitate radium began in 1965 at the Nordic Mine at Elliot Lake, Ontario. In the mid-60s and early 70s water quality studies indicated that discharges from uranium tailings areas were causing degradation to the upper part of the Serpent River water system. Studies into acid generation, revegetation, and leaching of radium were initiated by the mining companies and resulted in the construction of treatment plants at a number of sites. Abandoned tailings sites were revegetated. At hearings into the expansion of the Elliot Lake operations the issue of tailings management was a major item for discussion. As a result federal and provincial agencies developed guidelines for the siting and development of urnaium tailings areas prior to issuing operating licences. Western Canadian uranium producers do not have the acid generation problem of the Elliot Lake operations. The Rabbit Lake mill uses settling ponds followed by filtration. High-grade tailings from Cluff Lake are sealed in concrete and buried. Uranium producers feel that the interim criteria developed by the Atomic Energy Control Board, if adopted, would have a harmful effect on the viability of the Canadian uranium industry

  11. Verification of the AZNHEX code v.1.4 with MCNP6 for different reference cases

    International Nuclear Information System (INIS)

    Galicia A, J.; Francois L, J. L.; Bastida O, G. E.; Del Valle G, E.

    2017-09-01

    The codes that make up the AZTLAN platform (AZTHECA, AZTRAN, AZKIND and AZNHEX) are currently in the testing phase simulating a variety of nuclear reactor assemblies and cores to compare and validate the results obtained for a particular case, with codes globally used in the nuclear area such as CASMO, Serpent and MCNP. The objective of this work is to continue improving the future versions of the codes of the AZTLAN platform so that accurate and reliable results can be obtained for the user. To test the current version of the AZNHEX code, 3 cases were taken into account, the first being the simulation of a VVER-440 reactor assembly; for the second case, the assembly of a fast reactor cooled with helium was simulated and for the third case it was decided to take up the case of the core of a fast reactor cooled with sodium, this because the previous versions of AZNHEX did not show adequate results and, in addition, they presented a considerable amount of limitations. The comparison and validation of the results (neutron multiplication factor, radial power, radial flow, axial power) for these three cases were made using the code MCNP6. The results obtained show that this version of AZNHEX produces values of the neutron multiplication factor and the neutron and power flow distributions very close to those of MCNP6. (Author)

  12. Validation of the AZTRAN 1.1 code with problems Benchmark of LWR reactors

    International Nuclear Information System (INIS)

    Vallejo Q, J. A.; Bastida O, G. E.; Francois L, J. L.; Xolocostli M, J. V.; Gomez T, A. M.

    2016-09-01

    The AZTRAN module is a computational program that is part of the AZTLAN platform (Mexican modeling platform for the analysis and design of nuclear reactors) and that solves the neutron transport equation in 3-dimensional using the discrete ordinates method S_N, steady state and Cartesian geometry. As part of the activities of Working Group 4 (users group) of the AZTLAN project, this work validates the AZTRAN code using the 2002 Yamamoto Benchmark for LWR reactors. For comparison, the commercial code CASMO-4 and the free code Serpent-2 are used; in addition, the results are compared with the data obtained from an article of the PHYSOR 2002 conference. The Benchmark consists of a fuel pin, two UO_2 cells and two other of MOX cells; there is a problem of each cell for each type of reactor PWR and BWR. Although the AZTRAN code is at an early stage of development, the results obtained are encouraging and close to those reported with other internationally accepted codes and methodologies. (Author)

  13. Fuel analysis of a PBMR

    International Nuclear Information System (INIS)

    Bastida O, G. E.; Francois L, J. L.

    2015-09-01

    In this paper a neutronic analysis of fuel for a Pebble Bed Modular Reactor is presented, based on their composition and geometric distribution, having as main objective the use and utilization of thorium for the production of fuel for the operation of this reactor. For the study of these characteristics is necessary to use a code capable of carry out a reliable calculation of the main parameters of the fuel. Using the Monte Carlo method is suitable for simulating the neutron transport in the reactor core, which is the basis of Serpent code, with which the calculations for the analysis will be made. The results show the desirability of the use of thorium, since presents good conversion levels of fertile material to fissile, to produce U 233 by neutron capture, taking as a very important factor the distribution of materials in the core, which in this work had better results based on the neutron multiplication effective factor, formed by three right circular cylinders circumscribed, making that the core has three areas constituted by a mixture of plutonium oxide in the central and external areas, and thorium oxide in the intermediate area. (Author)

  14. Maine's MOLLOCKET and METALLAK: Adherents of God's Secret Spirit Signal, SSS, Applied Physicists of the EMF/Manitou, Doctors, Reincarnationists, "Potlachers," Confidants of the Powerful, and, they Did Own the Land.

    Science.gov (United States)

    Andrade, Jennifer; Ferreira, Nadja; Mc Leod, Roger D.

    2007-04-01

    Northeastern ``Indians,'' reputed to ``make the weather,'' actually, from youth, observed earth phenomena, including SSS. These are subtle and barely detectable visual artifacts of the electromagnetic field, special information that led/leads to their spiritual belief in reincarnation, which came from the EMF/SSS communication, backward and forward, (up to) seven generations. It commands communal, democratic, ``potlatch'' redistribution of accumulated wealth, Mother Earth's bounty, from their land, gifted by ``The Great Spirit,'' Manitou, Peru's Ñari Huallac, ``Serpent God.'' Genetics established the non-Asian origins of 1/3 of North American Indians. Linguistics indicates a major impact westwards to us. MILLInocket is ``Adherent of God (Spirit-signal) monk Cathar.'' Katahdin, with a shared root, has Manitou. After 1820, Gov. E. Lincoln and at least one US senator went westward to MetALLAk; his biography is by a Rumford, ME Knight of Pythias. Why? MOLLOCKET frequently asserted ownership of western Maine. ``Great Council Fires,'' religious ``Law Things,'' were at Merrymeeting Bay in pre-Colonial times. ``Medicine men/priests'' often participated as their applied scientist-statesmen. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.1

  15. Verification of the AZNHEX code v.1.4 with MCNP6 for different reference cases; Verificacion del codigo AZNHEX v.1.4 con MCNP6 para diferentes casos de referencia

    Energy Technology Data Exchange (ETDEWEB)

    Galicia A, J.; Francois L, J. L.; Bastida O, G. E. [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Ciudad Universitaria, Circuito Exterior s/n, 04510 Ciudad de Mexico (Mexico); Del Valle G, E., E-mail: jgaliciaa87@gmail.com [IPN, Escuela Superior de Fisica y Matematicas, Av. IPN s/n, 07738 Ciudad de Mexico (Mexico)

    2017-09-15

    The codes that make up the AZTLAN platform (AZTHECA, AZTRAN, AZKIND and AZNHEX) are currently in the testing phase simulating a variety of nuclear reactor assemblies and cores to compare and validate the results obtained for a particular case, with codes globally used in the nuclear area such as CASMO, Serpent and MCNP. The objective of this work is to continue improving the future versions of the codes of the AZTLAN platform so that accurate and reliable results can be obtained for the user. To test the current version of the AZNHEX code, 3 cases were taken into account, the first being the simulation of a VVER-440 reactor assembly; for the second case, the assembly of a fast reactor cooled with helium was simulated and for the third case it was decided to take up the case of the core of a fast reactor cooled with sodium, this because the previous versions of AZNHEX did not show adequate results and, in addition, they presented a considerable amount of limitations. The comparison and validation of the results (neutron multiplication factor, radial power, radial flow, axial power) for these three cases were made using the code MCNP6. The results obtained show that this version of AZNHEX produces values of the neutron multiplication factor and the neutron and power flow distributions very close to those of MCNP6. (Author)

  16. Validation of the AZTRAN 1.1 code with problems Benchmark of LWR reactors; Validacion del codigo AZTRAN 1.1 con problemas Benchmark de reactores LWR

    Energy Technology Data Exchange (ETDEWEB)

    Vallejo Q, J. A.; Bastida O, G. E.; Francois L, J. L. [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Xolocostli M, J. V.; Gomez T, A. M., E-mail: amhed.jvq@gmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2016-09-15

    The AZTRAN module is a computational program that is part of the AZTLAN platform (Mexican modeling platform for the analysis and design of nuclear reactors) and that solves the neutron transport equation in 3-dimensional using the discrete ordinates method S{sub N}, steady state and Cartesian geometry. As part of the activities of Working Group 4 (users group) of the AZTLAN project, this work validates the AZTRAN code using the 2002 Yamamoto Benchmark for LWR reactors. For comparison, the commercial code CASMO-4 and the free code Serpent-2 are used; in addition, the results are compared with the data obtained from an article of the PHYSOR 2002 conference. The Benchmark consists of a fuel pin, two UO{sub 2} cells and two other of MOX cells; there is a problem of each cell for each type of reactor PWR and BWR. Although the AZTRAN code is at an early stage of development, the results obtained are encouraging and close to those reported with other internationally accepted codes and methodologies. (Author)

  17. Particle accelerators, colliders, and the story of high energy physics. Charming the cosmic snake

    International Nuclear Information System (INIS)

    Jayakumar, Raghavan

    2012-01-01

    The Nordic mythological Cosmic Serpent, Ouroboros, is said to be coiled in the depths of the sea, surrounding the Earth with its tail in its mouth. In physics, this snake is a metaphor for the Universe, where the head, symbolizing the largest entity - the Cosmos - is one with the tail, symbolizing the smallest - the fundamental particle. Particle accelerators, colliders and detectors are built by physicists and engineers to uncover the nature of the Universe while discovering its building blocks. ''Charming the Cosmic Snake'' takes the readers through the science behind these experimental machines: the physics principles that each stage of the development of particle accelerators helped to reveal, and the particles they helped to discover. The book culminates with a description of the Large Hadron Collider, one of the world's largest and most complex machines operating in a 27-km circumference tunnel near Geneva. That collider may prove or disprove many of our basic theories about the nature of matter. The book provides the material honestly without misrepresenting the science for the sake of excitement or glossing over difficult notions. The principles behind each type of accelerator is made accessible to the undergraduate student and even to a lay reader with cartoons, illustrations and metaphors. Simultaneously, the book also caters to different levels of reader's background and provides additional materials for the more interested or diligent reader. (orig.)

  18. Monte Carlo Codes Invited Session

    International Nuclear Information System (INIS)

    Trama, J.C.; Malvagi, F.; Brown, F.

    2013-01-01

    This document lists 22 Monte Carlo codes used in radiation transport applications throughout the world. For each code the names of the organization and country and/or place are given. We have the following computer codes. 1) ARCHER, USA, RPI; 2) COG11, USA, LLNL; 3) DIANE, France, CEA/DAM Bruyeres; 4) FLUKA, Italy and CERN, INFN and CERN; 5) GEANT4, International GEANT4 collaboration; 6) KENO and MONACO (SCALE), USA, ORNL; 7) MC21, USA, KAPL and Bettis; 8) MCATK, USA, LANL; 9) MCCARD, South Korea, Seoul National University; 10) MCNP6, USA, LANL; 11) MCU, Russia, Kurchatov Institute; 12) MONK and MCBEND, United Kingdom, AMEC; 13) MORET5, France, IRSN Fontenay-aux-Roses; 14) MVP2, Japan, JAEA; 15) OPENMC, USA, MIT; 16) PENELOPE, Spain, Barcelona University; 17) PHITS, Japan, JAEA; 18) PRIZMA, Russia, VNIITF; 19) RMC, China, Tsinghua University; 20) SERPENT, Finland, VTT; 21) SUPERMONTECARLO, China, CAS INEST FDS Team Hefei; and 22) TRIPOLI-4, France, CEA Saclay

  19. Analysis of the thorium inclusion in the fuel of a fast reactor cooled by lead

    International Nuclear Information System (INIS)

    Juarez M, L. C.; Francois L, J. L.

    2017-09-01

    In the present work, we first verified a model of the European reactor cooled with lead (ELFR). The calculations were made with the code Monte Carlo serpent 2.27 and the library of cross sections Jeff-3.1. For this verification, three neutron parameters were compared: the evolution of the neutron multiplication factor, the Doppler constant and the effect of the vacuum fraction of the refrigerant, obtaining a good approximation with the reference values. Subsequently, the inclusion of thorium as a fertile material within the fuel was analyzed and the same neutron parameters were compared with the original fuel. The evolution of criticality for the case of thorium fuel differs significantly with respect to that of the original fuel (without thorium); this is due mainly to the breeding of the fissile isotope 233 U. Therefore, is possible to have a longer fuel cycle, favoring the availability factor of the plant, without compromising the performance of the reactor since both the Doppler constant and the effect of the vacuum fraction of the refrigerant show a similar tendency to those of the original fuel, being negative in both cases. (Author)

  20. Preliminary analysis of basic reactor physics of the Dual Fluid Reactor - 15270

    International Nuclear Information System (INIS)

    Wang, X.; Macian-Juan, R.; Seidl, M.

    2015-01-01

    The Dual Fluid Reactor (DFR) is a novel fast nuclear reactor concept invented by the IFK based on the Generation IV Molten Salt Reactor and the Liquid Metal Cooled Reactor. The DFR uses a chloride based molten fuel salt in order to harden the neutron spectrum. The molten fuel salt is cooled with a separated liquid lead loop, which in principle allows for higher power densities and better breeding performance. The DFR does not combine heat removal and breeding into a single circuit but separates the two functions into two independent circuits. Since there are attractive features mentioned in this design, the main task of this paper is to verify the model of the whole reactor based on this concept. For this purpose several calculations are presented, including steady state calculations, sensitivity calculations with regard to the nuclide cross sections, the temperature and geometry coefficient of k eff as well as the burnup calculation. The Monte Carlo calculation codes MCNP, SERPENT and SCALE are used for the analysis. As expected the study shows a significant negative reactivity feedback with temperature in the overall fission zone. For the coupled coolant and reflector design the temperature feedback is rather small for practical purposes such as reactor control during normal operation. In the view of these results the DFR in principle can be self-regulated totally by the temperature change of its own fuel salt and consequently can rely on fully passive safety systems for accident management

  1. O Rei Maia Kukulcán e seus discursos de propaganda política em Chichén Itzá

    Directory of Open Access Journals (Sweden)

    Alexandre Guida Navarro

    2013-08-01

    Full Text Available Chichén Itzá foi um populoso centro urbano maia responsável por tributar centenas de cidades, organizar um exército eficaz para os empreendimentos guerreiros e realizar comércio de longa distância com outras cidades maias e de outras etnias. Durante seu auge, no século IX, a cidade foi governada por um rei chamado Kukulcán, que foi responsável pela maioria das construções arquitetônicas da cidade. Tal governo foi marcado por uma eficiente propaganda política que foi planejada segundo um processo cognitivo de representação imagética do governante, cuja principal manifestação deu-se em forma de uma serpente emplumada. Estas imagens serviram de propaganda política para perpetuar a soberania deste rei, além de ser um registro imagético de sua importância na memória coletiva desta cidade maia.

  2. ON THE FORMATION OF A STABLE PENUMBRA IN A REGION OF FLUX EMERGENCE IN THE SUN

    Energy Technology Data Exchange (ETDEWEB)

    Murabito, M.; Guglielmino, S. L.; Zuccarello, F. [Dipartimento di Fisica e Astronomia—Sezione Astrofisica, Università degli Studi di Catania, Via S. Sofia 78, I-95123 Catania (Italy); Romano, P., E-mail: mmurabito@oact.inaf.it [INAF—Osservatorio Astrofisico di Catania, Via S. Sofia 78, I-95123 Catania (Italy)

    2017-01-01

    We studied the formation of the first penumbral sector around a pore in the following polarity of the NOAA Active Region (AR) 11490. We used a high spatial, spectral, and temporal resolution data set acquired by the Interferometric BIdimensional Spectrometer operating at the NSO/Dunn Solar Telescope, as well as data taken by the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory satellite. On the side toward the leading polarity, elongated granules in the photosphere and an arch filament system (AFS) in the chromosphere are present, while the magnetic field shows a sea-serpent configuration, indicating a region of magnetic flux emergence. We found that the formation of a stable penumbra in the following polarity of the AR begins in the area facing the opposite polarity located below the AFS in the flux emergence region, different from what was found by Schlichenmaier and colleagues. Moreover, during the formation of the first penumbral sector, the area characterized by magnetic flux density larger than 900 G and the area of the umbra increase.

  3. Monte Carlo Analysis of the Battery-Type High Temperature Gas Cooled Reactor

    Science.gov (United States)

    Grodzki, Marcin; Darnowski, Piotr; Niewiński, Grzegorz

    2017-12-01

    The paper presents a neutronic analysis of the battery-type 20 MWth high-temperature gas cooled reactor. The developed reactor model is based on the publicly available data being an `early design' variant of the U-battery. The investigated core is a battery type small modular reactor, graphite moderated, uranium fueled, prismatic, helium cooled high-temperature gas cooled reactor with graphite reflector. The two core alternative designs were investigated. The first has a central reflector and 30×4 prismatic fuel blocks and the second has no central reflector and 37×4 blocks. The SERPENT Monte Carlo reactor physics computer code, with ENDF and JEFF nuclear data libraries, was applied. Several nuclear design static criticality calculations were performed and compared with available reference results. The analysis covered the single assembly models and full core simulations for two geometry models: homogenous and heterogenous (explicit). A sensitivity analysis of the reflector graphite density was performed. An acceptable agreement between calculations and reference design was obtained. All calculations were performed for the fresh core state.

  4. Monte Carlo Analysis of the Battery-Type High Temperature Gas Cooled Reactor

    Directory of Open Access Journals (Sweden)

    Grodzki Marcin

    2017-12-01

    Full Text Available The paper presents a neutronic analysis of the battery-type 20 MWth high-temperature gas cooled reactor. The developed reactor model is based on the publicly available data being an ‘early design’ variant of the U-battery. The investigated core is a battery type small modular reactor, graphite moderated, uranium fueled, prismatic, helium cooled high-temperature gas cooled reactor with graphite reflector. The two core alternative designs were investigated. The first has a central reflector and 30×4 prismatic fuel blocks and the second has no central reflector and 37×4 blocks. The SERPENT Monte Carlo reactor physics computer code, with ENDF and JEFF nuclear data libraries, was applied. Several nuclear design static criticality calculations were performed and compared with available reference results. The analysis covered the single assembly models and full core simulations for two geometry models: homogenous and heterogenous (explicit. A sensitivity analysis of the reflector graphite density was performed. An acceptable agreement between calculations and reference design was obtained. All calculations were performed for the fresh core state.

  5. Determining the minimum required uranium carbide content for HTGR UCO fuel kernels

    International Nuclear Information System (INIS)

    McMurray, Jacob W.; Lindemer, Terrence B.; Brown, Nicholas R.; Reif, Tyler J.; Morris, Robert N.; Hunn, John D.

    2017-01-01

    Highlights: • The minimum required uranium carbide content for HTGR UCO fuel kernels is calculated. • More nuclear and chemical factors have been included for more useful predictions. • The effect of transmutation products, like Pu and Np, on the oxygen distribution is included for the first time. - Abstract: Three important failure mechanisms that must be controlled in high-temperature gas-cooled reactor (HTGR) fuel for certain higher burnup applications are SiC layer rupture, SiC corrosion by CO, and coating compromise from kernel migration. All are related to high CO pressures stemming from O release when uranium present as UO 2 fissions and the O is not subsequently bound by other elements. In the HTGR kernel design, CO buildup from excess O is controlled by the inclusion of additional uranium apart from UO 2 in the form of a carbide, UC x and this fuel form is designated UCO. Here general oxygen balance formulas were developed for calculating the minimum UC x content to ensure negligible CO formation for 15.5% enriched UCO taken to 16.1% actinide burnup. Required input data were obtained from CALPHAD (CALculation of PHAse Diagrams) chemical thermodynamic models and the Serpent 2 reactor physics and depletion analysis tool. The results are intended to be more accurate than previous estimates by including more nuclear and chemical factors, in particular the effect of transmuted Pu and Np oxides on the oxygen distribution as the fuel kernel composition evolves with burnup.

  6. La serpiente sobre la mesa: Autoridad y control de la lluvia en una narración oral huave (México

    Directory of Open Access Journals (Sweden)

    Alessandro Lupo

    2015-07-01

    Full Text Available In quest’articolo analizzo alcune versioni di una narrazione mitica huave, il cui protagonista è un fanciullo dai poteri prodigiosi, il quale, a causa dell’indiscrezione del padre, è costretto dalle autorità municipali ad affrontare ripetutamente il gigantesco serpente che provoca le piogge torrenziali che minacciano di sommergere il villaggio, finendo per venirne ucciso. Al di là della rappresentazione delle forze cosmiche contrapposte da cui dipende il delicato equilibrio climatico della regione huave, il racconto mostra come la capacità di controllare il regime delle piogge costituisca da tempo immemorabile uno dei principali attributi simbolici dei detentori dell’autorità politica, attorno al quale ruotano importanti pratiche rituali e si condensano tensioni riguardanti la contesa del potere fra generazioni e individui. La condotta dei diversi protagonisti del racconto mette in scena in maniera esemplare i principi su cui per i Huave si basa l’autorità, i modelli assiologici e comportamentali cui si devono attenere quanti ambiscono ad accedervi e a conservarla, le pericolose conseguenze che aspettano quanti contravvengano a tali norme.

  7. Feasibility to convert an advanced PWR from UO2 to a mixed (U,Th)O2 core

    International Nuclear Information System (INIS)

    Stefani, Giovanni Laranjo de; Maiorino, José Rubens; Moreira, João Manoel de Losada; Santos, Thiago Augusto dos; Rossi, Pedro Carlos Russo

    2017-01-01

    This work presents the neutronics and thermal hydraulics feasibility to convert the UO2 core of the Westinghouse AP1000 in a (U-Th)O 2 core, rather than the traditional uranium dioxide, for the purpose of reducing long-lived actinides, especially plutonium, and generates a stock pile of 233 U, which could in the future be used in advanced fuel cycles, in a more sustainable process and taking advantage of the large stock of thorium available on the planet and especially in Brazil. The reactor chosen as reference was the AP1000, which is considered to be one of the most reliable and modern reactor of the current Generation III, and its similarity to the reactors already consolidated and used in Brazil for electric power generation. The results show the feasibility and potentiality of the concept, without the necessity of changes in the core of the AP1000, and even with advantages over this. The neutron calculations were made by the SERPENT code. The results provided a maximum linear power density lower than the AP1000, favoring safety. In addition, the delayed neutron fraction and the reactivity coefficients proved to be adequate to ensure the safety of the concept. The results show that a production of about 260 Kg of 233 U per cycle is possible, with a minimum production of fissile plutonium that favors the use of the concept in U-Th cycles. (author)

  8. Fabrication and Evaluation of a Graphene Oxide-Based Capacitive Humidity Sensor

    Directory of Open Access Journals (Sweden)

    Jinfeng Feng

    2016-03-01

    Full Text Available In this study, a CMOS compatible capacitive humidity sensor structure was designed and fabricated on a 200 mm CMOS BEOL Line. A top Al interconnect layer was used as an electrode with a comb/serpent structure, and graphene oxide (GO was used as sensing material. XRD analysis was done which shows that GO sensing material has a strong and sharp (002 peak at about 10.278°, whereas graphite has (002 peak at about 26°. Device level CV and IV curves were measured in mini-environments at different relative humidity (RH level, and saturated salt solutions were used to build these mini-environments. To evaluate the potential value of GO material in humidity sensor applications, a prototype humidity sensor was designed and fabricated by integrating the sensor with a dedicated readout ASIC and display/calibration module. Measurements in different mini-environments show that the GO-based humidity sensor has higher sensitivity, faster recovery time and good linearity performance. Compared with a standard humidity sensor, the measured RH data of our prototype humidity sensor can match well that of the standard product.

  9. Fabrication and Evaluation of a Graphene Oxide-Based Capacitive Humidity Sensor.

    Science.gov (United States)

    Feng, Jinfeng; Kang, Xiaoxu; Zuo, Qingyun; Yuan, Chao; Wang, Weijun; Zhao, Yuhang; Zhu, Limin; Lu, Hanwei; Chen, Juying

    2016-03-01

    In this study, a CMOS compatible capacitive humidity sensor structure was designed and fabricated on a 200 mm CMOS BEOL Line. A top Al interconnect layer was used as an electrode with a comb/serpent structure, and graphene oxide (GO) was used as sensing material. XRD analysis was done which shows that GO sensing material has a strong and sharp (002) peak at about 10.278°, whereas graphite has (002) peak at about 26°. Device level CV and IV curves were measured in mini-environments at different relative humidity (RH) level, and saturated salt solutions were used to build these mini-environments. To evaluate the potential value of GO material in humidity sensor applications, a prototype humidity sensor was designed and fabricated by integrating the sensor with a dedicated readout ASIC and display/calibration module. Measurements in different mini-environments show that the GO-based humidity sensor has higher sensitivity, faster recovery time and good linearity performance. Compared with a standard humidity sensor, the measured RH data of our prototype humidity sensor can match well that of the standard product.

  10. Assessment of Neutronic Characteristics of Accident-Tolerant Fuel and Claddings for CANDU Reactors

    Directory of Open Access Journals (Sweden)

    Simon Younan

    2018-01-01

    Full Text Available The objective of this study was to evaluate accident-tolerant fuel (ATF concepts being considered for CANDU reactors. Several concepts, including uranium dioxide/silicon carbide (UO2-SiC composite fuel, dense fuels, microencapsulated fuels, and ATF cladding, were modelled in Serpent 2 to obtain reactor physics parameters, including important feedback parameters such as coolant void reactivity and fuel temperature coefficient. In addition, fuel heat transfer was modelled, and a simple accident model was tested on several ATF cases to compare with UO2. Overall, several concepts would require enrichment of uranium to avoid significant burnup penalties, particularly uranium-molybdenum (U-Mo and fully ceramic microencapsulated (FCM fuels. In addition, none of the fuel types have a significant advantage over UO2 in terms of overall accident response or coping time, though U-9Mo fuel melts significantly sooner due to its low melting point. Instead, the different ATF concepts appear to have more modest advantages, such as reduced fission product release upon cladding failure, or reduced hydrogen generation, though a proper risk assessment would be required to determine the magnitude of these advantages to weigh against economic disadvantages. The use of uranium nitride (UN enriched in N15 would increase exit burnup for natural uranium, providing a possible economic advantage depending on fuel manufacturing costs.

  11. Joseph Clover and the cobra: a tale of snake envenomation and attempted resuscitation with bellows in London, 1852.

    Science.gov (United States)

    Ball, C

    2010-07-01

    The Industrial Revolution saw the creation of many new jobs, but probably none more curious than that of zookeeper. The London Zoological Gardens, established for members in 1828, was opened to the general public in 1847. In 1852 the "Head Keeper in the Serpent Room", Edward Horatio Girling, spent a night farewelling a friend departing for Australia. He arrived at work in an inebriated state and was bitten on the face by a cobra that he was handling in a less than sensible manner. He was taken by cab to University College Hospital where he was resuscitated by a number of doctors, including Joseph Clover then the resident medical officer to the hospital and later to become the leading anaesthetist in London. Clover recorded this event in his diary along with the resuscitation method used. The patient eventually died but his treatment created a flurry of correspondence in the medical and lay press. Interestingly, the attempted resuscitation was with bellows, which had been abandoned by the Royal Humane Society twenty years earlier Clover records other cases of resuscitation with bellows at University College Hospital during his time as a resident medical officer there (1848 to 1853). There is a casebook belonging to Joseph Clover in the Geoffrey Kaye Museum, in Melbourne. This story is one of the many interesting stories uncovered during a study of this book and Clover's other personal papers.

  12. Comets in Indian Scriptures

    Science.gov (United States)

    Das Gupta, P.

    2016-01-01

    The Indo-Aryans of ancient India observed stars and constellations for ascertaining auspicious times in order to conduct sacrificial rites ordained by the Vedas. Naturally, they would have sighted comets and referred to them in the Vedic texts. In Rigveda (circa 1700-1500 BC) and Atharvaveda (circa 1150 BC), there are references to dhumaketus and ketus, which stand for comets in Sanskrit. Rigveda speaks of a fig tree whose aerial roots spread out in the sky (Parpola 2010). Had this imagery been inspired by the resemblance of a comet's tail with long and linear roots of a banyan tree (ficus benghalensis)? Varahamihira (AD 550) and Ballal Sena (circa AD 1100-1200) described a large number of comets recorded by ancient seers, such as Parashara, Vriddha Garga, Narada, and Garga, to name a few. In this article, we propose that an episode in Mahabharata in which a radiant king, Nahusha, who rules the heavens and later turns into a serpent after he kicked the seer Agastya (also the star Canopus), is a mythological retelling of a cometary event.

  13. Carbon Isotope Measurements of Experimentally-Derived Hydrothermal Mineral-Catalyzed Organic Products by Pyrolysis-Isotope Ratio Mass Spectrometry

    Science.gov (United States)

    Socki, Richard A.; Fu, Qi; Niles, Paul B.

    2011-01-01

    We report results of experiments to measure the C isotope composition of mineral catalyzed organic compounds derived from high temperature and high pressure synthesis. These experiments make use of an innovative pyrolysis technique designed to extract and measure C isotopes. To date, our experiments have focused on the pyrolysis and C isotope ratio measurements of low-molecular weight intermediary hydrocarbons (organic acids and alcohols) and serve as a proof of concept for making C and H isotope measurements on more complicated mixtures of solid-phase hydrocarbons and intermediary products produced during high temperature and high pressure synthesis on mineral-catalyzed surfaces. The impetus for this work stems from recently reported observations of methane detected within the Martian atmosphere [1-4], coupled with evidence showing extensive water-rock interaction during Martian history [5-7]. Methane production on Mars could be the result of synthesis by mineral surface-catalyzed reduction of CO2 and/or CO by Fischer-Tropsch Type (FTT) reactions during serpentization reactions [8,9]. Others have conducted experimental studies to show that FTT reactions are plausible mechanisms for low-molecular weight hydrocarbon formation in hydrothermal systems at mid-ocean ridges [10-12]. Further, recent experiments by Fu et al. [13] focus on examining detailed C isotope measurements of hydrocarbons produced by surface-catalyzed mineral reactions. Work described in this paper details the experimental techniques used to measure intermediary organic reaction products (alcohols and organic acids).

  14. Comparative static simulations of a CANDU6 cell using different transport codes

    Energy Technology Data Exchange (ETDEWEB)

    Mahjoub, M.; Koclas, J., E-mail: mehdi.mahjoub@polymtl.ca [Ecole Polytechnique de Montreal, QC (Canada)

    2015-07-01

    The solution of the time dependent Boltzmann equation remains quite a challenge. We are in the process of developing such a method using the stochastic Monte Carlo approach for two reasons: First, at the cell level, we will be able to obtain time dependent homogenized cross sections for use in full core diffusion calculations. Second, the Monte Carlo methods are scalable to perform full core if and when appropriate computer resources become available. The Time dependent approach will be concretized a new module that will be added to an existing Monte Carlo code. As a first step towards this goal, we need to choose the initial Monte Carlo code to be used as start point. For this reason, we have compared results concerning the void reactivity of a fresh fuel CANDU6 cell, using two Monte Carlo codes, namely VTT developed SERPENT and MIT developed OpenMC together with the deterministic DRAGON code. Several libraries are used in this comparison. We conclude that OpenMC is a good candidate for implementation of a time dependent simulation. (author)

  15. EVOLUTION. A four-legged snake from the Early Cretaceous of Gondwana.

    Science.gov (United States)

    Martill, David M; Tischlinger, Helmut; Longrich, Nicholas R

    2015-07-24

    Snakes are a remarkably diverse and successful group today, but their evolutionary origins are obscure. The discovery of snakes with two legs has shed light on the transition from lizards to snakes, but no snake has been described with four limbs, and the ecology of early snakes is poorly known. We describe a four-limbed snake from the Early Cretaceous (Aptian) Crato Formation of Brazil. The snake has a serpentiform body plan with an elongate trunk, short tail, and large ventral scales suggesting characteristic serpentine locomotion, yet retains small prehensile limbs. Skull and body proportions as well as reduced neural spines indicate fossorial adaptation, suggesting that snakes evolved from burrowing rather than marine ancestors. Hooked teeth, an intramandibular joint, a flexible spine capable of constricting prey, and the presence of vertebrate remains in the guts indicate that this species preyed on vertebrates and that snakes made the transition to carnivory early in their history. The structure of the limbs suggests that they were adapted for grasping, either to seize prey or as claspers during mating. Together with a diverse fauna of basal snakes from the Cretaceous of South America, Africa, and India, this snake suggests that crown Serpentes originated in Gondwana. Copyright © 2015, American Association for the Advancement of Science.

  16. Particle accelerators, colliders, and the story of high energy physics. Charming the cosmic snake

    Energy Technology Data Exchange (ETDEWEB)

    Jayakumar, Raghavan

    2012-07-01

    The Nordic mythological Cosmic Serpent, Ouroboros, is said to be coiled in the depths of the sea, surrounding the Earth with its tail in its mouth. In physics, this snake is a metaphor for the Universe, where the head, symbolizing the largest entity - the Cosmos - is one with the tail, symbolizing the smallest - the fundamental particle. Particle accelerators, colliders and detectors are built by physicists and engineers to uncover the nature of the Universe while discovering its building blocks. ''Charming the Cosmic Snake'' takes the readers through the science behind these experimental machines: the physics principles that each stage of the development of particle accelerators helped to reveal, and the particles they helped to discover. The book culminates with a description of the Large Hadron Collider, one of the world's largest and most complex machines operating in a 27-km circumference tunnel near Geneva. That collider may prove or disprove many of our basic theories about the nature of matter. The book provides the material honestly without misrepresenting the science for the sake of excitement or glossing over difficult notions. The principles behind each type of accelerator is made accessible to the undergraduate student and even to a lay reader with cartoons, illustrations and metaphors. Simultaneously, the book also caters to different levels of reader's background and provides additional materials for the more interested or diligent reader. (orig.)

  17. Mitochondrial introgression via ancient hybridization, and systematics of the Australian endemic pygopodid gecko genus Delma.

    Science.gov (United States)

    Brennan, Ian G; Bauer, Aaron M; Jackman, Todd R

    2016-01-01

    Of the more than 1500 species of geckos found across six continents, few remain as unfamiliar as the pygopodids - Family Pygopodidae (Gray, 1845). These gekkotans are limited to Australia (44 species) and New Guinea (2 species), but have diverged extensively into the most ecologically diverse limbless radiation save Serpentes. Current phylogenetic understanding of the family has relied almost exclusively on two works, which have produced and synthesized an immense amount of morphological, geographical, and molecular data. However, current interspecific relationships within the largest genus Delma Gray 1831 are based chiefly upon data from two mitochondrial loci (16s, ND2). Here, we reevaluate the interspecific relationships within the genus Delma using two mitochondrial and four nuclear loci (RAG1, MXRA5, MOS, DYNLL1), and identify points of strong conflict between nuclear and mitochondrial genomic data. We address mito-nuclear discordance, and remedy this conflict by recognizing several points of mitochondrial introgression as the result of ancient hybridization events. Owing to the legacy value and intraspecific informativeness, we suggest the continued use of ND2 as a phylogenetic marker. Results identify strong support for species groups, but relationships among these clades, and the placement of several enigmatic taxa remain uncertain. We suggest a more careful review of Delma australis and the 'northwest Australia' clade. Accurately assessing and addressing species richness and relationships within this endemic Australian Gekkotan genus is relevant for understanding patterns of squamate speciation across the region. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Underestimation of nuclear fuel burnup – theory, demonstration and solution in numerical models

    Directory of Open Access Journals (Sweden)

    Gajda Paweł

    2016-01-01

    Full Text Available Monte Carlo methodology provides reference statistical solution of neutron transport criticality problems of nuclear systems. Estimated reaction rates can be applied as an input to Bateman equations that govern isotopic evolution of reactor materials. Because statistical solution of Boltzmann equation is computationally expensive, it is in practice applied to time steps of limited length. In this paper we show that simple staircase step model leads to underprediction of numerical fuel burnup (Fissions per Initial Metal Atom – FIMA. Theoretical considerations indicates that this error is inversely proportional to the length of the time step and origins from the variation of heating per source neutron. The bias can be diminished by application of predictor-corrector step model. A set of burnup simulations with various step length and coupling schemes has been performed. SERPENT code version 1.17 has been applied to the model of a typical fuel assembly from Pressurized Water Reactor. In reference case FIMA reaches 6.24% that is equivalent to about 60 GWD/tHM of industrial burnup. The discrepancies up to 1% have been observed depending on time step model and theoretical predictions are consistent with numerical results. Conclusions presented in this paper are important for research and development concerning nuclear fuel cycle also in the context of Gen4 systems.

  19. Porocephalus species (Pentastomida infecting Boa constrictor (Boidae and Lachesis muta (Viperidae in northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Waltécio de Oliveira Almeida

    2008-01-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2008v21n2p165 Espécies de Porocephalus (Pentastomida infectando Boa constrictor (Boidae e Lachesis muta (Viperidae na Região Nordeste do Brasil.  O Brasil possui uma grande diversidade de cobras, mas há poucos trabalhos realizados sobre parasitismo destas por pentastomídeos. No intuito de investigar o parasitismo pulmonar por pentastomídeos em grandes cobras na região nordeste, foram examinados seis espécimes de Boa constrictor e duas de Lachesis muta pertencentes à coleção do Serpentário da Universidade Federal de Pernambuco–UFPE, todos coletadas em localidades de mata úmida (Mata Atlântica. Apenas um espécime de B. constrictor estava infectado por Porocephalus sp. (intensidade de infecção 5,0. Apenas um espécime de L. muta estava infectado por P. stilesi (intensidade de infecção 15,0.

  20. Did Indians of the Americas Preserve Linguistic Place-names Like Willimantic, CT, Indicating Some Islamic Interactions and Applied Physics Use, Before Columbus?

    Science.gov (United States)

    Crory, Erica; Mc Leod, Roger D.

    2007-10-01

    Modern Peruvians document: ``Ñari Huallac is the name of the town in the north of Peru (Piura) where our families come from. The words Ñari Huallac mean Serpent God, [editorial emphasis by underlining script is added], and are some of the few words which remain from the ancient Tallan civilization.'' Tallan seems related to The God, Allah, of Islam, as are Alaska, Allagash, Illinois, Willimantic, CT, and, in Maine, Metallak, Mollocket and Millinocket, Allahpatah, of Florida, and Allegheny of Pennsylvania. With this significance lies the partially concealed evidence that all three monotheistic faiths, during the times indicated by the language, understood there was a fundamental connection between The God, and what we would call today the electromagnetic field, EMF, of Mother Earth. Metallak: Doctor (at) The God (Spirit-signal, EMF), an ecclesiastical title, like Willimantic, The God Spirit-signal (where there is a) doctor. Alaska: The God Jesus Christ Spirit-signal (EMF). Millinocket: Adherent of The God monk Cathar, provides a reference date of about 1250 A.D. Illinois: The God Spirit-signal (EMF-detecting) monk. Mollocket asserted ownership of western Maine, until 1816. What did she know of importance from her war-hostage days in Boston?

  1. Present status and future plan of development on National Nuclear Forensics Library at JAEA

    International Nuclear Information System (INIS)

    Kimura, Yoshiki; Shinohara, Nobuo; Funatake, Yoshio; Sato, Kaneaki; Toda, Nobufumi; Shinoda, Yoshiharu; Watahiki, Masaru; Kuno, Yusuke

    2013-01-01

    Japan Atomic Energy Agency (JAEA) has initiated R and D project on nuclear forensics technology such as analytical technologies towards the establishment of nuclear forensics capabilities in Japan. National Nuclear Forensics Library (NNFL) is one of the fundamental nuclear forensics capabilities and a prototype NNFL has been developed as one topic of the R and D project at JAEA. Main objective of NNFL is to determine whether a seized nuclear or other radioactive material from nuclear security event (e.g. illicit trafficking) is originated from one's country or not. Analytical data of the seized material are compared with the existing materials populated in a NNFL, and its attributions such as origin and history will be identified. This paper describes the current status and future plan on the development of prototype NNFL. The outline and the results of the participation in an international table top exercise on NNFL named 'Galaxy Serpent' are also reported in the present paper. (author)

  2. Coupling between the differential and perturbation theory methods for calculating sensitivity coefficients in nuclear transmutation problems; Acoplamento entre os metodos diferencial e da teoria da perturbacao para o calculo dos coeficientes de sensibilidade em problemas de transmutacao nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Lubianka Ferrari Russo

    2014-07-01

    The main target of this study is to introduce a new method for calculating the coefficients of sensibility through the union of differential method and generalized perturbation theory, which are the two methods generally used in reactor physics to obtain such variables. These two methods, separated, have some issues turning the sensibility coefficients calculation slower or computationally exhaustive. However, putting them together, it is possible to repair these issues and build a new equation for the coefficient of sensibility. The method introduced in this study was applied in a PWR reactor, where it was performed the sensibility analysis for the production and {sup 239}Pu conversion rate during 120 days (1 cycle) of burnup. The computational code used for both burnup and sensibility analysis, the CINEW, was developed in this study and all the results were compared with codes widely used in reactor physics, such as CINDER and SERPENT. The new mathematical method for calculating the sensibility coefficients and the code CINEW provide good numerical agility and also good efficiency and security, once the new method, when compared with traditional ones, provide satisfactory results, even when the other methods use different mathematical approaches. The burnup analysis, performed using the code CINEW, was compared with the code CINDER, showing an acceptable variation, though CINDER presents some computational issues due to the period it was built. The originality of this study is the application of such method in problems involving temporal dependence and, not least, the elaboration of the first national code for burnup and sensitivity analysis. (author)

  3. Discrimination of irradiated MOX fuel from UOX fuel by multivariate statistical analysis of simulated activities of gamma-emitting isotopes

    Science.gov (United States)

    Åberg Lindell, M.; Andersson, P.; Grape, S.; Hellesen, C.; Håkansson, A.; Thulin, M.

    2018-03-01

    This paper investigates how concentrations of certain fission products and their related gamma-ray emissions can be used to discriminate between uranium oxide (UOX) and mixed oxide (MOX) type fuel. Discrimination of irradiated MOX fuel from irradiated UOX fuel is important in nuclear facilities and for transport of nuclear fuel, for purposes of both criticality safety and nuclear safeguards. Although facility operators keep records on the identity and properties of each fuel, tools for nuclear safeguards inspectors that enable independent verification of the fuel are critical in the recovery of continuity of knowledge, should it be lost. A discrimination methodology for classification of UOX and MOX fuel, based on passive gamma-ray spectroscopy data and multivariate analysis methods, is presented. Nuclear fuels and their gamma-ray emissions were simulated in the Monte Carlo code Serpent, and the resulting data was used as input to train seven different multivariate classification techniques. The trained classifiers were subsequently implemented and evaluated with respect to their capabilities to correctly predict the classes of unknown fuel items. The best results concerning successful discrimination of UOX and MOX-fuel were acquired when using non-linear classification techniques, such as the k nearest neighbors method and the Gaussian kernel support vector machine. For fuel with cooling times up to 20 years, when it is considered that gamma-rays from the isotope 134Cs can still be efficiently measured, success rates of 100% were obtained. A sensitivity analysis indicated that these methods were also robust.

  4. Experiências sôbre a transmissão do Trypanosoma cruzi por sanguessugas e de tripanosomas de vertebrados de sangue frio por triatomíneos Experiments of the transmission of Trypanosoma cruzi by leechs and cold blooded vertebrate trypanosomas by triatominae

    Directory of Open Access Journals (Sweden)

    Samuel B. Pessôa

    1969-06-01

    Full Text Available Observou-se que o Trypanosoma cruzi não se multiplica na sanguessuga (Haementeria lutzi Pinto; os tripanosomas sugados degeneram após algum tempo; outros permanecem aparentemente normais, porém 48 horas após a ingestão infectante acabam morrendo. Observou-se ainda que os tripanosomas parasitas da rã (T. rotatorium e T. leptodactyli bem como o T. hogei, parasita da serpente Rachidelus brazili, não se multiplicam no intestino dos triatomíneos. O mais resistente (o T. leptodactyli, permanece vivo até 72 horas após a ingestão infectante, porém as outras duas espécies (T. rotatorium e T. hogei não resistem mais de 24 horas após serem sugadas pelos triatomíneos.Trypanosoma cruzi does not reproduce itself in the leech (Haementerm lutzi Pinto; the ingested trypanosomes degenerate after some time; other organisms remain apparently normal, however dying 48 hours after the feeding of the leechs. The parasite trypanosomas of the frog (T. rotatorium and T. leptodactyli as well as those parasiting the ophidian Rachidelus brazili (T. hogei do not multiply in the intestine of the triatominae. The most resistent species (T. leptocbactyli remains alive 72 hours after the feeding of the triatominae; the other two, however, do not survive more than 24 hours.

  5. Tracking multi-walled carbon nanotubes inside oat (Avena sativa L.) plants and assessing their effect on growth, yield, and mammalian (human) cell viability

    Science.gov (United States)

    Joshi, Anjali; Kaur, Simranjeet; Singh, Pargat; Dharamvir, Keya; Nayyar, Harsh; Verma, Gaurav

    2018-05-01

    Our findings show that oxidized multi-walled carbon nanotubes (MWCNT) having serpent-like morphology and smaller sizes (diameter of 35 nm and lengths of 200-300 nm) are compatible with oat plant tissues. Applied by seed-priming method as 90 µg/ml concentration, these serpentine MWCNT (having open-end caps) enter the oat plant and traverse the cells. Tracking of MWCNT inside sections and tissues during growth of oat plant has been done using special sample preparation. We present clear images of MWCNT inside the primed seeds and vascular bundles, the conducting tissues of root and shoot of oat. A dye fluorescein isothiocyanate non-covalently bonded to MWCNT also helped in detecting the path through circumferential perimeters of the oat channels, using fluorescence and confocal microscopy. The presence of MWCNT inside oat enhanced the growth of xylem cells by about 1.85-fold in vasculature of shoots. Compared to controls, the chlorophyll content increased by 57%, while photosynthetic activity enhanced by 15% for the same sample in MWCNT-primed plants. Overall, the growth factors were also augmented leading to significant increase in yield components. No toxic effects of MWCNT were observed in the DNA of the primed plants, and in the human cell lines treated with grains harvested from the MWCNT-primed plants. Our study provides some new insights about the role of MWCNT in plants and their potential benefits in agriculture.

  6. Micrurus snake venoms activate human complement system and generate anaphylatoxins

    Directory of Open Access Journals (Sweden)

    Tanaka Gabriela D

    2012-01-01

    Full Text Available Abstract Background The genus Micrurus, coral snakes (Serpentes, Elapidae, comprises more than 120 species and subspecies distributed from the south United States to the south of South America. Micrurus snake bites can cause death by muscle paralysis and further respiratory arrest within a few hours after envenomation. Clinical observations show mainly neurotoxic symptoms, although other biological activities have also been experimentally observed, including cardiotoxicity, hemolysis, edema and myotoxicity. Results In the present study we have investigated the action of venoms from seven species of snakes from the genus Micrurus on the complement system in in vitro studies. Several of the Micrurus species could consume the classical and/or the lectin pathways, but not the alternative pathway, and C3a, C4a and C5a were generated in sera treated with the venoms as result of this complement activation. Micrurus venoms were also able to directly cleave the α chain of the component C3, but not of the C4, which was inhibited by 1,10 Phenanthroline, suggesting the presence of a C3α chain specific metalloprotease in Micrurus spp venoms. Furthermore, complement activation was in part associated with the cleavage of C1-Inhibitor by protease(s present in the venoms, which disrupts complement activation control. Conclusion Micrurus venoms can activate the complement system, generating a significant amount of anaphylatoxins, which may assist due to their vasodilatory effects, to enhance the spreading of other venom components during the envenomation process.

  7. Genomic regression of claw keratin, taste receptor and light-associated genes provides insights into biology and evolutionary origins of snakes.

    Science.gov (United States)

    Emerling, Christopher A

    2017-10-01

    Regressive evolution of anatomical traits often corresponds with the regression of genomic loci underlying such characters. As such, studying patterns of gene loss can be instrumental in addressing questions of gene function, resolving conflicting results from anatomical studies, and understanding the evolutionary history of clades. The evolutionary origins of snakes involved the regression of a number of anatomical traits, including limbs, taste buds and the visual system, and by analyzing serpent genomes, I was able to test three hypotheses associated with the regression of these features. The first concerns two keratins that are putatively specific to claws. Both genes that encode these keratins are pseudogenized/deleted in snake genomes, providing additional evidence of claw-specificity. The second hypothesis is that snakes lack taste buds, an issue complicated by conflicting results in the literature. I found evidence that different snakes have lost one or more taste receptors, but all snakes examined retained at least one gustatory channel. The final hypothesis addressed is that the earliest snakes were adapted to a dim light niche. I found evidence of deleted and pseudogenized genes with light-associated functions in snakes, demonstrating a pattern of gene loss similar to other dim light-adapted clades. Molecular dating estimates suggest that dim light adaptation preceded the loss of limbs, providing some bearing on interpretations of the ecological origins of snakes. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. PROVENANCE SNAKES OF GENUS Bothrops AND Crotalus (VIPERIDAE CATALOGED IN SERPENTARIUM ZOO UNIVERSITY OF CAXIAS DO SUL (UCS

    Directory of Open Access Journals (Sweden)

    Ezequiel Capeletti

    2016-09-01

    Full Text Available Snakes are reptiles that have large environmental adaptations, which favored it's distribution among the various ecosystems. In Brazil, there are found 392 species of snakes, while in Rio Grande do Sul (RS, this research field, 79 species have been described, of which there is the Viperidae family. The objective of this work is to verify the origin of snakes of genus Bothrops and Crotalus, according to the records of the last 15 years of the serpentarium the University of Caxias do Sul, representing the first survey in captivity of the northeastern region of RS. By extension, we seek to investigate whether there is a relationship between the amount of snakes records and abiotic factors: precipitation, temperature and humidity during the period. The research was developed at UCS's serpentarium, by documental analysis of notebook records describing serpents entries between the years 2000 and 2014, in addition to literature review that helped to understand the distribution of the species and gather of the environmental parameters at the Instituto Nacional de Metereologia for further analysis. It was found that the received species are distributed in 26 cities in the RS state, of which the highlights are the municities of Nova Petrópolis and Caxias do Sul, with 148 and 42 individuals respectively. Further, it was found that there was no relationship between the amount of animals and registered temperature, precipitation and humidity. Keywords: Geographic distribution; Bothrops; Crotalus; abiotic factors; northeastern RS.

  9. Evaluation of platelet number and function and fibrinogen level in patients bitten by snakes of the Bothrops genus

    Directory of Open Access Journals (Sweden)

    Fábio Cardoso Luan

    1995-03-01

    Full Text Available Platelet function and plasma fibrinogen levels were evaluated in 14 patients, 10 males and 4females, aged 13-59years bitten by Bothrops genus snakes. There was a statistical difference (p Foram avaliadas a função plaquetária e os níveis séricos de fibrinogênio em 14 doentes picados por serpentes do gênero Bothrops, sendo 10 do sexo masculino e 4 do sexo feminino, com idades compreendidas entre 13 e 59 anos. Houve diferença estatística (p < 0,05 entre os níveis séricos defibrinogênio avaliados 24 e 48 horas após o acidente. Houve tendência à normalização após 48 horas do tratamento. A plaquetopenia foi evidente nas avaliações de 24 e 48 horas. Houve tendência à nomalização no 8o dia após o tratamento (p <0,05. Os níveis de produtos de degradação defibrina (PDF mostraram-se alterados em 83,33 % dos pacientes avaliados. Os autores sugerem que a hipoagregação esteja relacionada com níveis baixos de fibrinogênio e elevados de PDF.

  10. Da esquizofrenia à antropofagia: leituras da história

    Directory of Open Access Journals (Sweden)

    Vinícius Nicastro Honesko

    2009-11-01

    Full Text Available From the confluence of readings, which in principle would be called disparate, the present essay intents to expose a zone of threshold among the proposes of Aby Warburg, in his The Ritual of the Serpent, going over the readings of the dialectical images in Benjamin, to the problem of the signatures in Foucault, until the conception of anthropophagy of Oswald de Andrade. In a very first moment, some analyses about the conception of symbol in Warburg and the compositional mode of his Mnemosyne are exposed. Then, an exposition of Benjamin ?s theorizations about the dialectics images is done, always using the comprehensions from his contemporary readers (Giorgio Agamben, Georges Didi-Huberman, among others. Therefore, an approximation of the dialectical images to the idea of signature in Michel Foucault can be done; such approximation is only possible having as a support a method, here called archeological (a study of the origin – arké, which enables the proposition of an anachronism in the reading(s of history(ies. Finally, it analyses how an anthropophagic conception of history – from Oswald de Andrade – can be a strategic way to break with a schizophrenic chronology of history and a passage to an anachronic (anthropophagic reading of history, that does not aim to suture the limits postulated by the tradition of the occidental thinking (civilized/primitive, rational/irrational etc., but to dilute them into thresholds, in order to give a new possibility to what (history seemed not to have anymore.

  11. The story of the condom

    Directory of Open Access Journals (Sweden)

    Fahd Khan

    2013-01-01

    Full Text Available Condoms have been a subject of curiosity throughout history. The idea of safer sex has been explored in ancient and modern history, and has been used to prevent venereal diseases. We conducted a historical and medical review of condoms using primary and secondary sources as well as using the RSM library and the internet. These resources show that the first use of a condom was that of King Minos of Crete. Pasiphae, his wife, employed a goat′s bladder in the vagina so that King Minos would not be able to harm her as his semen was said to contain "scorpions and serpents" that killed his mistresses. To Egyptians, condom-like glans caps were dyed in different colours to distinguish between different classes of people and to protect themselves against bilharzia. The Ancient Romans used the bladders of animals to protect the woman; they were worn not to prevent pregnancy but to prevent contraction of venereal diseases. Charles Goodyear, the inventor, utilized vulcanization, the process of transforming rubber into malleable structures, to produce latex condoms. The greater use of condoms all over the world in the 20 th and 21 st centuries has been related to HIV. This account of the use of condoms demonstrates how a primitive idea turned into an object that is used globally with a forecast estimated at 18 billion condoms to be used in 2015 alone.

  12. Measurement of reactivity in ADS reactors considering an exponential decay after an interruption in the external proton source

    Energy Technology Data Exchange (ETDEWEB)

    Henrice Junior, Edson; Gonçalves, Alessandro C., E-mail: ejunior@con.ufrj.br [Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Palma, Daniel A.P., E-mail: dapalma@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro - RJ (Brazil)

    2017-07-01

    The online monitoring of reactivity in ADS reactors is of paramount importance for the operations of such systems. This work is dedicated to the prediction of reactivity from a decay of the neutron population after a pulse from the external source. For that, a pulse from an external source in an ADS reactor was simulated with Serpent Reactor Physics code. From the data obtained, it was possible to make an adjustment, based on a combination of exponentials. The coefficient of the exponential for the dominating term of the sum of exponentials is compared to the simplified solution of the neutron diffusion equation, thus obtaining the reactivity. The method used for the adjustment has the advantage of not requiring data that is equally spaced, and of being easily programmable, waiving the use of specific software for linear adjustments. The preliminary results of the research showed a 750 pcm deviation in relation to the value found of -3,630 pcm obtained through point kinetics, and as a result should be the object of further study. (author)

  13. Comparative Neutronics Analysis of DIMPLE S06 Criticality Benchmark with Contemporary Reactor Core Analysis Computer Code Systems

    Directory of Open Access Journals (Sweden)

    Wonkyeong Kim

    2015-01-01

    Full Text Available A high-leakage core has been known to be a challenging problem not only for a two-step homogenization approach but also for a direct heterogeneous approach. In this paper the DIMPLE S06 core, which is a small high-leakage core, has been analyzed by a direct heterogeneous modeling approach and by a two-step homogenization modeling approach, using contemporary code systems developed for reactor core analysis. The focus of this work is a comprehensive comparative analysis of the conventional approaches and codes with a small core design, DIMPLE S06 critical experiment. The calculation procedure for the two approaches is explicitly presented in this paper. Comprehensive comparative analysis is performed by neutronics parameters: multiplication factor and assembly power distribution. Comparison of two-group homogenized cross sections from each lattice physics codes shows that the generated transport cross section has significant difference according to the transport approximation to treat anisotropic scattering effect. The necessity of the ADF to correct the discontinuity at the assembly interfaces is clearly presented by the flux distributions and the result of two-step approach. Finally, the two approaches show consistent results for all codes, while the comparison with the reference generated by MCNP shows significant error except for another Monte Carlo code, SERPENT2.

  14. Fission products detection in irradiated TRIGA fuel by means of gamma spectroscopy and MCNP calculation.

    Science.gov (United States)

    Cagnazzo, M; Borio di Tigliole, A; Böck, H; Villa, M

    2018-05-01

    Aim of this work was the detection of fission products activity distribution along the axial dimension of irradiated fuel elements (FEs) at the TRIGA Mark II research reactor of the Technische Universität (TU) Wien. The activity distribution was measured by means of a customized fuel gamma scanning device, which includes a vertical lifting system to move the fuel rod along its vertical axis. For each investigated FE, a gamma spectrum measurement was performed along the vertical axis, with steps of 1 cm, in order to determine the axial distribution of the fission products. After the fuel elements underwent a relatively short cooling down period, different fission products were detected. The activity concentration was determined by calibrating the gamma detector with a standard calibration source of known activity and by MCNP6 simulations for the evaluation of self-absorption and geometric effects. Given the specific TRIGA fuel composition, a correction procedure is developed and used in this work for the measurement of the fission product Zr 95 . This measurement campaign is part of a more extended project aiming at the modelling of the TU Wien TRIGA reactor by means of different calculation codes (MCNP6, Serpent): the experimental results presented in this paper will be subsequently used for the benchmark of the models developed with the calculation codes. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Feasibility to convert an advanced PWR from UO{sub 2} to a mixed (U,Th)O{sub 2} core

    Energy Technology Data Exchange (ETDEWEB)

    Stefani, Giovanni Laranjo de; Maiorino, José Rubens; Moreira, João Manoel de Losada; Santos, Thiago Augusto dos, E-mail: giovanni_laranjo@yahoo.com.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil); Rossi, Pedro Carlos Russo [Department of Energy, System, Territory, and Construction Engineering (DESTEC), Pisa (Italy)

    2017-07-01

    This work presents the neutronics and thermal hydraulics feasibility to convert the UO2 core of the Westinghouse AP1000 in a (U-Th)O{sub 2} core, rather than the traditional uranium dioxide, for the purpose of reducing long-lived actinides, especially plutonium, and generates a stock pile of {sup 233}U, which could in the future be used in advanced fuel cycles, in a more sustainable process and taking advantage of the large stock of thorium available on the planet and especially in Brazil. The reactor chosen as reference was the AP1000, which is considered to be one of the most reliable and modern reactor of the current Generation III, and its similarity to the reactors already consolidated and used in Brazil for electric power generation. The results show the feasibility and potentiality of the concept, without the necessity of changes in the core of the AP1000, and even with advantages over this. The neutron calculations were made by the SERPENT code. The results provided a maximum linear power density lower than the AP1000, favoring safety. In addition, the delayed neutron fraction and the reactivity coefficients proved to be adequate to ensure the safety of the concept. The results show that a production of about 260 Kg of {sup 233}U per cycle is possible, with a minimum production of fissile plutonium that favors the use of the concept in U-Th cycles. (author)

  16. Notas sobre predação em uma taxocenose de anfíbios anuros no sudeste do Brasil Predation notes in an anuran amphibians assemblage from southeastern Brazil

    Directory of Open Access Journals (Sweden)

    José P. Pombal Jr

    2007-01-01

    Full Text Available Anfíbios anuros são predados por todos os grupos de vertebrados e muitos invertebrados. Todavia os estudos sobre predação em anfíbios anuros ainda são esparsos e anedóticos. Neste estudo são fornecidas informações sobre predação de anuros de uma assembléia no sudeste do Brasil. Invertebrados (aranhas e barata d’agua, a rã Leptodactylus cf. ocellatus e cinco espécies serpentes (quatro Colubridae e um Viperidae predaram espécies ou indivíduos de pequeno porte.Anuran amphibians are preyer by all vertebrate groups and several invertebrates. However, predation studies on amphibians are still occasional and anecdotic. Herein, informations on predation of an anuran assemblage of southeastern Brazil are provided. Invertebrates (spiders and water bugs, the frog Leptodactylus cf. ocellatus, and five snake species (four Colubridae and one Viperidae preyer on small individuals or small anuran species.

  17. A method for predicting fuel maintenance in once-through MSRs

    International Nuclear Information System (INIS)

    Ridley, Gavin; Chvala, Ondrej

    2017-01-01

    Highlights: •Novel method to control LEU-fueled MSR reactivity and chemistry is developed. •The method relies on adjusting material flows only. •Ten year full power depletion of a FLiBe core demonstrates the method. •Material flows and reactor physics data are presented. •Graphite lifetime and trifluoride actinide limits are satisfied. -- Abstract: Liquid fuel molten salt reactors allow reactivity control by material addition. This paper presents a method to adjust material flows in a molten salt reactor to keep the core critical, and to maintain desired reduction-oxidation potential in the core salt melt. The method is aimed at low-enriched uranium fueled thermal systems. It is developed as a Python library and uses Serpent2 Monte-Carlo transport and depletion code. A toy 300 MW(th) reactor with a FLiBe carrier salt is employed to demonstrate the performance of the method over 10 full power years. Results of the calculation are presented, including material flows, conversion ratio, effective delayed neutron fraction, and expected limits on trifluoride concentrations and graphite lifetime are investigated. This method lays a foundation for future studies including fuel cycle performance of molten salt reactors and dynamic behavior of the core during depletion.

  18. An assessment of prompt neutron reproduction time in a reflector dominated fast critical system: ELECTRA

    International Nuclear Information System (INIS)

    Suvdantsetseg, E.; Wallenius, J.

    2014-01-01

    Highlights: • Prompt neutron reproduction time of ELECTRA is evaluated. • Static and dynamic reproduction times are distinguished for ELECTRA. • Avery-Cohn’s two-region prompt neutron theory is applied. - Abstract: In this paper, an accurate method to evaluate the prompt neutron reproduction time for a reflector dominated fast critical reactor, ELECTRA, is discussed. To adequately handle the problem, explicit time dependent Monte Carlo calculations with MCNP, applying repeated time cut-off technique, are used and compared against the σ∼1/v time dependent absorber method, applying artificial cross-section data in the Monte Carlo code SERPENT. The results show that when a reflector plays a major role in criticality for fast neutron reactor, the two methods predict different physical parameters (Λ=69±2 ns and Λ=83±1 ns for time cut-off and the 1/v method respectively). The reason is explained by applying Avery-Cohn’s two-region prompt neutron model

  19. 226Ra and other radionuclides in water, vegetation, and tissues of beavers (Castor canadensis) from a watershed containing U tailings neat Elliot Lake, Canada

    International Nuclear Information System (INIS)

    Clulow, F.V.; Mirka, M.A.; Dave, N.K.; Lim, T.P.

    1991-01-01

    Radionuclide levels were measured in tissues, gut contents, diet items, and water at site of capture, of adult beavers from the Serpent River drainage basin which contains U tailings at Elliot Lake, Ontario, and from nearby control sites. Levels of 226 Ra in beaver bone, muscle and kidney were highest in animals from locations close to U tailing; liver levels did not vary by site. Environmental 226 Ra levels were within ranges previously reported at these or similar locations elsewhere; levels in beaver gut contents reflected levels in diet items. Concentration ratios exceeded unity only between some vegetation items and beaver bone at the Elliot Lake site and were less than 0.19 between vegetation and other tissues. In two beavers with tissue levels of 226 Ra higher than others sampled, neither 232 Th nor 230 Th were detected in bone, muscle or liver tissues. U-238 was measurable in bone, muscle and liver; 228 Th in bone, 210 Po bone, muscle and liver; and 210 Pb was measurable only in bone. Estimated yearly intakes of radionuclides by people eating beavers were calculated to be below current allowable levels set by the Canadian regulatory authorities. (author)

  20. T'ao-t'ieh, a motif of Chinese funerary art as the iconographic counterpart of Cinnabar, an alchemical drug.

    Science.gov (United States)

    Mahdihassan, S

    1982-01-01

    The agency conferring resurrection is soul or its emblem. The earliest conception of soul is blood. Its Redness penetrates subsoil and is taken up by serpent, from whence arises snake-soul, later snake-god. Blood vapours is the other fraction arising upwards. It becomes wraith bird, later soul bird, and finally bird god. Blood as whole gave snake-god plus bird-god. A winged-cobra became snake-god and bird-god or together, one-as-all. Red Cock was its equivalent. As substance came cinnabar, red like blood and sublimable like soul. Dragon was idealized snake-god. Then Dragon-god plus Bird-god became the equal of blood soul, the magical power. T'ao-t'ieh is Dragon-plus-Bird, snake-god plus bird-god, the equivalent of Cosmic soul. Then cinnabar as the equal of blood soul and T'ao-t'ieh, the emblem of Cosmic soul, each were capable of conferring resurrection and have been interred in Chinese graves.

  1. Particle accelerators, colliders, and the story of high energy physics charming the cosmic snake

    CERN Document Server

    Jayakumar, Raghavan

    2012-01-01

    The Nordic mythological Cosmic Serpent, Ouroboros, is said to be coiled in the depths of the sea, surrounding the Earth with its tail in its mouth. In physics, this snake is a metaphor for the Universe, where the head, symbolizing the largest entity – the Cosmos – is one with the tail, symbolizing the smallest – the fundamental particle. Particle accelerators, colliders and detectors are built by physicists and engineers to uncover the nature of the Universe while discovering its building blocks. “Charming the Cosmic Snake” takes the readers through the science behind these experimental machines: the physics principles that each stage of the development of particle accelerators helped to reveal, and the particles they helped to discover. The book culminates with a description of the Large Hadron Collider, one of the world’s largest and most complex machines operating in a 27-km circumference tunnel near Geneva. That collider may prove or disprove many of our basic theories about the nature of matt...

  2. Nova Scotia: ``Feu Follet" At Cheticamp, and Also the Phenomena At L'Sitkuk of the Mi'Kmaw, May Be Electromagnetic In Nature.

    Science.gov (United States)

    Ochs, Michael Ann; McLeod, Roger D.

    2001-11-01

    There is a strong tradition that ``feu follet" exists at the cemetery associated with the Acadian French at Cheticamp. It is described as a blue light, and may actually be the equivalent of an ascending, positively charged stream of ions in the atmosphere, just like the blue-light column that is often a precursor of a storm's lightning-strike. Similar phenomena are at America's Stonehenge, at a stone serpent effigy site in Ohio, and just north of the Lakes Memphremagog and Magog of Vermont and Canada. At the Bear River L'sitkuk Reservation area, which seems to us to have been a most unsuitable site, was deliberately chosen by the Mi'kmaw for their living area. Was this because certain properties of the electromagnetic field (EMF) are evident to them there, which also seem to be reflected in their legends? We hope to establish that these disparate cultures and their separate worldviews can be confirmed by the presence of particular EMF signatures. *This paper does not represent the views of the United States Environmental Protection Agency.

  3. New burnup calculation of TRIGA IPR-R1 reactor

    International Nuclear Information System (INIS)

    Meireles, Sincler P. de; Campolina, Daniel de A.M.; Santos, Andre A. Campagnole dos; Menezes, Maria A.B.C.; Mesquita, Amir Z.

    2015-01-01

    The IPR-R1 TRIGA Mark I research reactor, located at the Nuclear Technology Development Center - CDTN, Belo Horizonte, Brazil, operates since 1960.The reactor is operating for more than fifty years and has a long history of operation. Determining the current composition of the fuel is very important to calculate various parameters. The reactor burnup calculation has been performed before, however, new techniques, methods, software and increase of the processing capacity of the new computers motivates new investigations to be performed. This work presents the evolution of effective multiplication constant and the results of burnup. This new model has a more detailed geometry with the introduction of the new devices, like the control rods and the samarium discs. This increase of materials in the simulation in burnup calculation was very important for results. For these series of simulations a more recently cross section library, ENDF/B-VII, was used. To perform the calculations two Monte Carlo particle transport code were used: Serpent and MCNPX. The results obtained from two codes are presented and compared with previous studies in the literature. (author)

  4. Analysis of the thorium inclusion in the fuel of a fast reactor cooled by lead; Analisis de la inclusion de torio en el combustible de un reactor rapido enfriado por plomo

    Energy Technology Data Exchange (ETDEWEB)

    Juarez M, L. C.; Francois L, J. L., E-mail: lcjm@ier.unam.mx [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Paseo Cuauhnahuac 8532, Col. Progreso, 62550 Jiutepec, Morelos (Mexico)

    2017-09-15

    In the present work, we first verified a model of the European reactor cooled with lead (ELFR). The calculations were made with the code Monte Carlo serpent 2.27 and the library of cross sections Jeff-3.1. For this verification, three neutron parameters were compared: the evolution of the neutron multiplication factor, the Doppler constant and the effect of the vacuum fraction of the refrigerant, obtaining a good approximation with the reference values. Subsequently, the inclusion of thorium as a fertile material within the fuel was analyzed and the same neutron parameters were compared with the original fuel. The evolution of criticality for the case of thorium fuel differs significantly with respect to that of the original fuel (without thorium); this is due mainly to the breeding of the fissile isotope {sup 233}U. Therefore, is possible to have a longer fuel cycle, favoring the availability factor of the plant, without compromising the performance of the reactor since both the Doppler constant and the effect of the vacuum fraction of the refrigerant show a similar tendency to those of the original fuel, being negative in both cases. (Author)

  5. KEANEKARAGAMAN SPESIES ULAR DI DESA PERING, KECAMATAN BLAHBATUH, KABUPATEN GIANYAR, BALI

    Directory of Open Access Journals (Sweden)

    I GEDE MADE ARIUS HADY BUDIADA

    2017-06-01

    Full Text Available Snakes are cold-blooded reptiles belong to the Order Squamata, Suborder Serpentes. Snakes often found in lowlands, highlands, trees, soil, water and swamps. People in the Pering village especially in Banjar Perang Sada have less knowledge about venomous and non-venomous snakes. Therefore, it is important to investigate the diversity of snakes in the Pering village, Blahbatuh, Gianyar. This study was conducted on 28 January – 4 February 2015. Data collection was performed by direct observation along the potential snake habitats in two plots rice field near residential area and near the Pura Beji. Data collection was performed during night time from at 7:00 to 11:00 PM with sampling focused on Banjar Perang Sada. Individual snake found was cought and identified in situ. This research found 9 species of snakes namely, Ahaetulla prasina, Boiga cynodon, Dendrelaphis pictus, Pareas carinatus, Ptyas korros, Rhabdophis chrysargos, Xenochrophis piscator, Bungarus fasciatus, and Trimeresurus insularis, the most commonly found was Dendrelaphis pictus.

  6. Associação de plasma sanguíneo ao tratamento de envenenamento botrópico em equino: relato de caso

    Directory of Open Access Journals (Sweden)

    A.C. Camplesi

    Full Text Available RESUMO O presente trabalho tem por objetivo relatar um caso de envenenamento botrópico em um equino, fêmea, seis anos de idade, da raça Quarto de Milha, pesando 460kg, que foi atendido no hospital veterinário da FCAV/Unesp, Campus de Jaboticabal, SP. No exame clínico, observou-se aumento bilateral de narina, com extrema sensibilidade ao toque, presença das marcas da presa da serpente na região rostral de focinho, mucosas róseas com petéquias. No exame de sangue, pôde-se detectar alteração no tempo de coagulação sanguínea (>30 minutos. O animal permaneceu internado, sendo instituída a seguinte terapia: soro antiofídico polivalente, transfusão de plasma sanguíneo equino, fluidoterapia intensa, flunixin meglumine e sulfa associado ao trimetoprim. A associação da transfusão de plasma sanguíneo equino ao tratamento convencional foi de extrema importância para correção da coagulopatia causada pelo acidente ofídico. A égua apresentou melhora clínica e resolução do quadro de envenenamento após cinco dias da internação.

  7. [Theriac: medicine and antidote].

    Science.gov (United States)

    Parojcic, Dusanka; Stupar, Dragan; Mirica, Milica

    2003-06-01

    Theriac was an ancient multi-ingredient preparation; originating as a cure for the bites of serpents, mad dogs and wild beasts, it later became an antidote to all known poisons. The name theriac (treacle), (Greek theriake, Latin theriaca, French thériaque) was derived from the Greek for wild beast - theriakos. The first formula was created by Mithridates Vl, King of Pontus, a skillful ruler but a monster of cruelty, who, living in such a fear of being poisoned, took a great interest in toxicology. In the 1st century AD, Nero's personal physician Andromachus improved the formula of Antidotum Mithridatium by adding flesh of vipers, which was commonly believed to be the best antidote against snakebite, and by increasing the proportion of opium. It became known as Theriac of Andromachus, and contained 64 ingredients including various minerals, herbals, poisons and animal flesh and blood, all combined with honey in the form of electuarium. Later it became the cure-all medicine which, accumulating all the simples into one form, was supposed to be a universal panacea against all diseases. In the Middle Ages this famous electuarium become a patent medicine and entered official dispensaries and pharmacopoeias. The most famous and expensive Theriac in Europe was that of Venice. It was not until the l8th century that it was excluded from medical use.

  8. Fuel analysis of a PBMR; Analisis de combustible de un PBMR

    Energy Technology Data Exchange (ETDEWEB)

    Bastida O, G. E.; Francois L, J. L., E-mail: gbo729@yahoo.com.mx [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico)

    2015-09-15

    In this paper a neutronic analysis of fuel for a Pebble Bed Modular Reactor is presented, based on their composition and geometric distribution, having as main objective the use and utilization of thorium for the production of fuel for the operation of this reactor. For the study of these characteristics is necessary to use a code capable of carry out a reliable calculation of the main parameters of the fuel. Using the Monte Carlo method is suitable for simulating the neutron transport in the reactor core, which is the basis of Serpent code, with which the calculations for the analysis will be made. The results show the desirability of the use of thorium, since presents good conversion levels of fertile material to fissile, to produce U{sup 233} by neutron capture, taking as a very important factor the distribution of materials in the core, which in this work had better results based on the neutron multiplication effective factor, formed by three right circular cylinders circumscribed, making that the core has three areas constituted by a mixture of plutonium oxide in the central and external areas, and thorium oxide in the intermediate area. (Author)

  9. Proverbs 30:18-19 in the Light of Ancient Mesopotamian Cuneiform Texts

    Directory of Open Access Journals (Sweden)

    Böck, Barbara

    2009-12-01

    Full Text Available The meaning of Proverbs 30:18-19 has long been disputed. Most scholars interpret the Biblical couplets textually on stylistic features only; an explanation of the contextual association between the four motifs mentioned (eagle, serpent, boat, man and woman has not yet been undertaken. The present paper aims at shedding light on the motivation for this association, taking into consideration ancient Near Eastern cuneiform compositions for the first time. It is further suggested that Proverbs 30:18-19 derived originally from a riddle that had its setting in a wedding ceremony.El significado de Proverbios 30:18-19 sigue desafiando la exégesis de los biblistas. La mayoría de los comentaristas interpretan los versos bíblicos textualmente, ciñéndose al análisis de las figuras de estilo. Sin embargo, todavía no se ha dado ninguna explicación a la asociación contextual entre los cuatro motivos del proverbio (águila, serpiente, barco, hombre y mujer. Por primera vez, este artículo estudia composiciones de la literatura cuneiforme que ofrecen un telón de fondo para interpretar el sentido de los distintos elementos y del conjunto del proverbio bíblico. Según esta nueva lectura, Proverbios 30:18-19 describiría una adivinanza propuesta durante una ceremonia matrimonial.

  10. Higher order methods for burnup calculations with Bateman solutions

    International Nuclear Information System (INIS)

    Isotalo, A.E.; Aarnio, P.A.

    2011-01-01

    Highlights: → Average microscopic reaction rates need to be estimated at each step. → Traditional predictor-corrector methods use zeroth and first order predictions. → Increasing predictor order greatly improves results. → Increasing corrector order does not improve results. - Abstract: A group of methods for burnup calculations solves the changes in material compositions by evaluating an explicit solution to the Bateman equations with constant microscopic reaction rates. This requires predicting representative averages for the one-group cross-sections and flux during each step, which is usually done using zeroth and first order predictions for their time development in a predictor-corrector calculation. In this paper we present the results of using linear, rather than constant, extrapolation on the predictor and quadratic, rather than linear, interpolation on the corrector. Both of these are done by using data from the previous step, and thus do not affect the stepwise running time. The methods were tested by implementing them into the reactor physics code Serpent and comparing the results from four test cases to accurate reference results obtained with very short steps. Linear extrapolation greatly improved results for thermal spectra and should be preferred over the constant one currently used in all Bateman solution based burnup calculations. The effects of using quadratic interpolation on the corrector were, on the other hand, predominantly negative, although not enough so to conclusively decide between the linear and quadratic variants.

  11. Art exhibit focuses on African astronomy

    Science.gov (United States)

    Showstack, Randy

    2012-07-01

    Connections between Africans and astronomy are the focus of a new exhibition in the National Museum of African Art in Washington, D. C. "African Cosmos: Stellar Arts," which includes artwork, cultural items, and scientific displays from ancient to contemporary times, is the first major exhibit "that brings together arts and science focused on Africa's contribution to keen observations of the heavens over time," curator Christine Mullen Kreamer said at a 20 June news briefing. Among the exhibit's nearly 100 objects are an ancient Egyptian mummy board that includes a representation of the sky goddess Nut, sculptures by the Dogon people of Mali depicting figures in relation to the cosmos, a video that uses data from two square degrees of the Hubble Space Telescope Cosmic Evolution Survey, and a nearly floor-to-ceiling "Rainbow Serpent" constructed of plastic containers by Benin artist Hazoume. An untitled acrylic painting (Figure 1) by South African Gavin Jantjes evokes a myth of the Khoi San people of southern Africa, as it portrays a girl throwing evening fire embers into the night sky, where they remained as the Milky Way.

  12. Coupling between the differential and perturbation theory methods for calculating sensitivity coefficients in nuclear transmutation problems

    International Nuclear Information System (INIS)

    Rossi, Lubianka Ferrari Russo

    2014-01-01

    The main target of this study is to introduce a new method for calculating the coefficients of sensibility through the union of differential method and generalized perturbation theory, which are the two methods generally used in reactor physics to obtain such variables. These two methods, separated, have some issues turning the sensibility coefficients calculation slower or computationally exhaustive. However, putting them together, it is possible to repair these issues and build a new equation for the coefficient of sensibility. The method introduced in this study was applied in a PWR reactor, where it was performed the sensibility analysis for the production and 239 Pu conversion rate during 120 days (1 cycle) of burnup. The computational code used for both burnup and sensibility analysis, the CINEW, was developed in this study and all the results were compared with codes widely used in reactor physics, such as CINDER and SERPENT. The new mathematical method for calculating the sensibility coefficients and the code CINEW provide good numerical agility and also good efficiency and security, once the new method, when compared with traditional ones, provide satisfactory results, even when the other methods use different mathematical approaches. The burnup analysis, performed using the code CINEW, was compared with the code CINDER, showing an acceptable variation, though CINDER presents some computational issues due to the period it was built. The originality of this study is the application of such method in problems involving temporal dependence and, not least, the elaboration of the first national code for burnup and sensitivity analysis. (author)

  13. Adaptive evolution of the venom-targeted vWF protein in opossums that eat pitvipers.

    Directory of Open Access Journals (Sweden)

    Sharon A Jansa

    Full Text Available The rapid evolution of venom toxin genes is often explained as the result of a biochemical arms race between venomous animals and their prey. However, it is not clear that an arms race analogy is appropriate in this context because there is no published evidence for rapid evolution in genes that might confer toxin resistance among routinely envenomed species. Here we report such evidence from an unusual predator-prey relationship between opossums (Marsupialia: Didelphidae and pitvipers (Serpentes: Crotalinae. In particular, we found high ratios of replacement to silent substitutions in the gene encoding von Willebrand Factor (vWF, a venom-targeted hemostatic blood protein, in a clade of opossums known to eat pitvipers and to be resistant to their hemorrhagic venom. Observed amino-acid substitutions in venom-resistant opossums include changes in net charge and hydrophobicity that are hypothesized to weaken the bond between vWF and one of its toxic snake-venom ligands, the C-type lectin-like protein botrocetin. Our results provide the first example of rapid adaptive evolution in any venom-targeted molecule, and they support the notion that an evolutionary arms race might be driving the rapid evolution of snake venoms. However, in the arms race implied by our results, venomous snakes are prey, and their venom has a correspondingly defensive function in addition to its usual trophic role.

  14. Radiation shielding properties of a novel cement–basalt mixture for nuclear energy applications

    Energy Technology Data Exchange (ETDEWEB)

    Ipbüker, Cagatay; Nulk, Helena; Gulik, Volodymyr [University of Tartu, Institute of Physics (Estonia); Biland, Alex [HHK Technologies, Houston (United States); Tkaczyk, Alan Henry, E-mail: alan@ut.ee [University of Tartu, Institute of Physics (Estonia)

    2015-04-01

    Highlights: • Basalt fiber is a relatively cheap material that can be used as reinforcement. • Gamma-ray attenuation remains relatively stable with addition of basalt fiber. • Neutron attenuation remains relatively stable with addition of basalt fiber. • Cement–basalt mixture has a good potential for use in nuclear energy applications. - Abstract: The radiation shielding properties of a new proposed building material, a novel cement–basalt fiber mixture (CBM), are investigated. The authors analyze the possibility of this material to be a viable substitute to outgoing materials in nuclear energy applications, which will lead to a further sustained development of nuclear energy in the future. This computational study involves four types of concrete with various amounts of basalt fiber in them. The gamma-ray shielding characteristics of proposed CBM material are investigated with the help of WinXCom program, whereas the neutron shielding characteristics are computed by the Serpent code. For gamma-ray shielding, we find that the attenuation coefficients of concretes with basalt fibers are not notably influenced by the addition of fibers. For neutron shielding, additional basalt fiber in mixture presents negligible effect on neutron radiation shielding. With respect to radiation shielding, it can be concluded that basalt fibers have good potential as an addition to heavyweight concrete for nuclear energy applications.

  15. The simplified P3 approach on a trigonal geometry in the nodal reactor code DYN3D

    International Nuclear Information System (INIS)

    Duerigen, S.; Fridman, E.

    2011-01-01

    DYN3D is a three-dimensional nodal diffusion code for steady-state and transient analyses of Light-Water Reactors with square and hexagonal fuel assembly geometries. Currently, several versions of the DYN3D code are available including a multi-group diffusion and a simplified P 3 (SP 3 ) neutron transport option. In this work, the multi-group SP 3 method based on trigonal-z geometry was developed. The method is applicable to the analysis of reactor cores with hexagonal fuel assemblies and allows flexible mesh refinement, which is of particular importance for WWER-type Pressurized Water Reactors as well as for innovative reactor concepts including block type High-Temperature Reactors and Sodium Fast Reactors. In this paper, the theoretical background for the trigonal SP 3 methodology is outlined and the results of a preliminary verification analysis are presented by means of a simplified WWER-440 core test example. The accordant cross sections and reference solutions were produced by the Monte Carlo code SERPENT. The DYN3D results are in good agreement with the reference solutions. The average deviation in the nodal power distribution is about 1%. (Authors)

  16. Measurement of reactivity in ADS reactors considering an exponential decay after an interruption in the external proton source

    International Nuclear Information System (INIS)

    Henrice Junior, Edson; Gonçalves, Alessandro C.

    2017-01-01

    The online monitoring of reactivity in ADS reactors is of paramount importance for the operations of such systems. This work is dedicated to the prediction of reactivity from a decay of the neutron population after a pulse from the external source. For that, a pulse from an external source in an ADS reactor was simulated with Serpent Reactor Physics code. From the data obtained, it was possible to make an adjustment, based on a combination of exponentials. The coefficient of the exponential for the dominating term of the sum of exponentials is compared to the simplified solution of the neutron diffusion equation, thus obtaining the reactivity. The method used for the adjustment has the advantage of not requiring data that is equally spaced, and of being easily programmable, waiving the use of specific software for linear adjustments. The preliminary results of the research showed a 750 pcm deviation in relation to the value found of -3,630 pcm obtained through point kinetics, and as a result should be the object of further study. (author)

  17. Ticks infesting amphibians and reptiles in Pernambuco, Northeastern Brazil Carrapatos infestando anfíbios e répteis em Pernambuco, Nordeste do Brasil

    Directory of Open Access Journals (Sweden)

    Filipe Dantas-Torres

    2008-12-01

    Full Text Available Ticks infesting amphibians and reptiles in the State of Pernambuco are reviewed, based on the current literature and new collections recently carried out by the authors. To date, three tick species have been found on amphibians and reptiles in Pernambuco. Amblyomma fuscum appears to be exclusively associated with Boa constrictor, its type host. Amblyomma rotundatum has a relatively low host-specificity, being found on toads, snakes, and iguana. Amblyomma dissimile has been found on a lizard and also small mammals (i.e., rodents and marsupials. New tick-host associations and locality records are given.Os carrapatos encontrados infestando anfíbios e répteis no Estado de Pernambuco são revisados com base na literatura atual e em novas coletas realizadas recentemente pelos autores. Até o momento, três espécies de carrapatos foram encontradas sobre anfíbios e répteis em Pernambuco. Amblyomma fuscum parece estar exclusivamente associado à Boa constrictor, seu hospedeiro-tipo. Amblyomma rotundatum tem uma especificidade parasitária relativamente baixa, sendo encontrado em sapos, serpentes e iguana. Amblyomma dissimile já foi encontrado sobre um lagarto e também sobre pequenos mamíferos (isto é, roedores e marsupiais. Novas associações carrapato-hospedeiro e novos registros de localidades são apresentados.

  18. Radiation shielding properties of a novel cement–basalt mixture for nuclear energy applications

    International Nuclear Information System (INIS)

    Ipbüker, Cagatay; Nulk, Helena; Gulik, Volodymyr; Biland, Alex; Tkaczyk, Alan Henry

    2015-01-01

    Highlights: • Basalt fiber is a relatively cheap material that can be used as reinforcement. • Gamma-ray attenuation remains relatively stable with addition of basalt fiber. • Neutron attenuation remains relatively stable with addition of basalt fiber. • Cement–basalt mixture has a good potential for use in nuclear energy applications. - Abstract: The radiation shielding properties of a new proposed building material, a novel cement–basalt fiber mixture (CBM), are investigated. The authors analyze the possibility of this material to be a viable substitute to outgoing materials in nuclear energy applications, which will lead to a further sustained development of nuclear energy in the future. This computational study involves four types of concrete with various amounts of basalt fiber in them. The gamma-ray shielding characteristics of proposed CBM material are investigated with the help of WinXCom program, whereas the neutron shielding characteristics are computed by the Serpent code. For gamma-ray shielding, we find that the attenuation coefficients of concretes with basalt fibers are not notably influenced by the addition of fibers. For neutron shielding, additional basalt fiber in mixture presents negligible effect on neutron radiation shielding. With respect to radiation shielding, it can be concluded that basalt fibers have good potential as an addition to heavyweight concrete for nuclear energy applications

  19. Radiation shielding properties of high performance concrete reinforced with basalt fibers infused with natural and enriched boron

    International Nuclear Information System (INIS)

    Zorla, Eyüp; Ipbüker, Cagatay; Biland, Alex; Kiisk, Madis; Kovaljov, Sergei; Tkaczyk, Alan H.; Gulik, Volodymyr

    2017-01-01

    Highlights: • Basalt fiber infused with natural and enriched boron in varying proportions. • Gamma-ray attenuation remains stable with addition of basalt-boron fiber. • Improvement in neutron shielding for nuclear facilities producing fast fission spectrum. • Basalt-boron fiber could decrease the shielding thickness in thermal spectrum reactors. - Abstract: The importance of radiation shielding is increasing in parallel with the expansion of the application areas of nuclear technologies. This study investigates the radiation shielding properties of two types of high strength concrete reinforced with basalt fibers infused with 12–20% boron oxide, containing varying fractions of natural and enriched boron. The gamma-ray shielding characteristics are analyzed with the help of the WinXCom, whereas the neutron shielding characteristics are modeled and computed by Monte Carlo Serpent code. For gamma-ray shielding, the attenuation coefficients of the studied samples do not display any significant variation due to the addition of basalt-boron fibers at any mixing proportion. For neutron shielding, the addition of basalt-boron fiber has negligible effects in the case of very fast neutrons (14 MeV), but it could considerably improve the neutron shielding of concrete for nuclear facilities producing a fast fission spectrum (e.g. with reactors as BN-800, FBTR) and thermal neutron spectrum (Light Water Reactors (LWR)). It was also found that basalt-boron fiber could decrease the thickness of radiation shielding material in thermal spectrum reactors.

  20. Adaptabilidade e estabilidade de genótipos de soja avaliados para resistência ao oídio Adaptability and stability of soybean genotypes evaluated for resistance to powdery mildew

    Directory of Open Access Journals (Sweden)

    Derval Gomes Pereira

    2008-10-01

    Full Text Available O objetivo desta pesquisa foi identificar genótipos de soja com adaptabilidade e estabilidade de comportamento para resistência ao oídio em condições de campo. O trabalho foi realizado no Campo Experimental Professor Diogo Alves de Mello, do Departamento de Fitotecnia, da Universidade Federal de Viçosa (UFV, em Viçosa, Minas Gerais. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições, disposto em parcelas subdivididas, com 15 genótipos (parcelas e sete épocas de avaliação (subparcela. A avaliação da incidência e severidade do oídio nos genótipos foi realizada por meio da quantificação visual do nível de infecção (NI provocado pelo oídio, sendo avaliados o nível de infecção da área foliar infectada pelo oídio (NIAFI e o nível de infecção do folíolo mais infectado pelo oídio (NIFI. Foram realizadas a análise de variância e análise de adaptabilidade e estabilidade conforme EBERHART & RUSSELL (1966. Os resultados permitiram tirar as seguintes conclusões: os genótipos que apresentaram os melhores níveis de resistência, em geral, também foram os de melhor adaptabilidade e estabilidade, tanto para NIAFI quanto para NIFI, com destaque para: UFV 89-361826 T2, UFV 94-334268, UFV-16 e UFV-19, FT-10 RC5 (F3, FT-Abyara RC6 (F2, Doko RC, FT-Abyara RC5 (F4, enquanto que os mais suscetíveis foram os de pior previsibilidade (estabilidade de comportamento, com destaque para UFV 94-5126, FT-104, UFV 94-3500, FT-Cristalina, FT-Estrela e BR-16.The objective of this research was to identify soybean genotypes with good adaptability and stability of behavior for resistance to powdery mildew in field conditions. The work was carried out at the Professor Diogo Alves de Mello Experimental Station, Agronomy Department of the Federal University of Viçosa (UFV, Viçosa, Minas Gerais. The experiment was arranged in a randomized block design, in split-plots, with 15 genotypes (plots and seven

  1. Post-reconstruction full power and shut down level 2 PSA study for Unit 1 of Bohunice V1 NPP

    International Nuclear Information System (INIS)

    Kovacs, Z.

    2003-01-01

    The level 2 PSA model of the J. Bohunice V1 NPP was developed in the RISK SPECTRUM Professional code with the following objectives: to identify the ways in which radioactive releases from the plant can occur following the core damage; to calculate the magnitudes and frequency of the release; to provide insights into the plant behaviour during a severe accident; to provide a framework for understanding containment failure modes; the impact of the phenomena that could occur during and following core damage and have the potential to challenge the integrity of the confinement; to support the severe accident management and development of SAMGs. The magnitudes of release categories are calculated using: the MAAP4/VVER for reactor operation and shutdown mode with closed reactor vessel and the MELCOR code for shutdown mode with open reactor vessel. In this paper an overview of the Level 2 PSA methodology; description of the confinement; the interface between the level 1 and 2 PSA and accident progression analyses are presented. An evaluation of the confinement failure modes and construction of the confinement event trees as well as definition of release categories, source term analysis and sensitivity analyses are also discussed. The presented results indicate that: 1)for the full power operation - there is an 25% probability that the confinement will successfully maintain its integrity and prevent an uncontrolled fission product release; the most likely mode of release from the confinement is a confinement bypass after SGTM with conditional probability of 30%; the conditional probability for the confinement isolation failure probability without spray is 5%, for early confinement failure at the vessel failure is 4%, for other categories 1% or less; 2) for the shutdown operating modes - the shutdown risk is high for the open reactor vessel and open confinement; important severe accident sequences exists for release categories: RC5.1, RC5.2 and RC6.2

  2. Study of performance of electronic dosemeters in continuous and pulsed X-radiation beams

    International Nuclear Information System (INIS)

    Guimaraes, Margarete Cristina

    2014-01-01

    Personal radiation monitoring is a basic procedure to verify the compliance to regulatory requirements for radiological protection. Electronic personal dosimeters (EPD) based on solid state detectors have largely been used for personnel monitoring; including for pulsed radiation beams where their responses are not well known and deficiencies have been reported. In this work, irradiation conditions for testing the response of EPDs in both continuous and pulsed X-ray beams were studied to be established in a constant potential Seifert-Pantak and in a medical Pulsar 800 Plus VMI X-ray machines. Characterization of X-ray beams was done in terms of tube voltage, half-value layer, mean energy and air kerma rate. A Xi R/F Unfors solid state dosimeter used as reference for air kerma measurements was verified against a RC-6 and 10X6-6 Radical ionization chambers as far its metrological coherence. Rad-60 RADOS, PDM- 11 Aloka and EPD MK2 Thermo electron EPDs were selected to be tested in terms of relative intrinsic error and energy response in similar to IEC RQR, IEC RQA and ISO N reference radiations. Results demonstrated the reliability of the solid state Xi R/F Unfors dosimeter to be as reference dosimeter although its response was affected by heavily filtered beams. Results also showed that relative intrinsic errors in the response of the EPDs in terms of personal dose equivalent, Hp(10), were higher than the requirement established for continuous beams. In pulsed beams, some EPDs showed inadequate response and high relative intrinsic errors. This work stressed the need of performing additional checks for EPDs, besides the limited 137 Cs beam calibration, before using them in pulsed X-ray beams. (author)

  3. Quantitative DFT modeling of product concentration in organometallic reactions: Cu-mediated pentafluoroethylation of benzoic acid chlorides as a case study.

    Science.gov (United States)

    Jover, Jesús

    2017-11-08

    DFT calculations are widely used for computing properties, reaction mechanisms and energy profiles in organometallic reactions. A qualitative agreement between the experimental and the calculated results seems to usually be enough to validate a computational methodology but recent advances in computation indicate that a nearly quantitative agreement should be possible if an appropriate DFT study is carried out. Final percent product concentrations, often reported as yields, are by far the most commonly reported properties in experimental metal-mediated synthesis studies but reported DFT studies have not focused on predicting absolute product amounts. The recently reported stoichiometric pentafluoroethylation of benzoic acid chlorides (R-C 6 H 4 COCl) with [(phen)Cu(PPh 3 )C 2 F 5 ] (phen = 1,10-phenanthroline, PPh 3 = triphenylphosphine) has been used as a case study to check whether the experimental product concentrations can be reproduced by any of the most popular DFT approaches with high enough accuracy. To this end, the Gibbs energy profile for the pentafluoroethylation of benzoic acid chloride has been computed using 14 different DFT methods. These computed Gibbs energy profiles have been employed to build kinetic models predicting the final product concentration in solution. The best results are obtained with the D3-dispersion corrected B3LYP functional, which has been successfully used afterwards to model the reaction outcomes of other simple (R = o-Me, p-Me, p-Cl, p-F, etc.) benzoic acid chlorides. The product concentrations of more complex reaction networks in which more than one position of the substrate may be activated by the copper catalyst (R = o-Br and p-I) are also predicted appropriately.

  4. Electronically Strongly Coupled Divinylheterocyclic-Bridged Diruthenium Complexes.

    Science.gov (United States)

    Pfaff, Ulrike; Hildebrandt, Alexander; Korb, Marcus; Oßwald, Steffen; Linseis, Michael; Schreiter, Katja; Spange, Stefan; Winter, Rainer F; Lang, Heinrich

    2016-01-11

    Complexes [{Ru(CO)Cl(PiPr3 )2 }2 (μ-2,5-(CH-CH)2 -(c) C4 H2 E] (E=NR; R=C6 H4 -4-NMe2 (10 a), C6 H4 -4-OMe (10 b), C6 H4 -4-Me (10 c), C6 H5 (10 d), C6 H4 -4-CO2 Et (10 e), C6 H4 -4-NO2 (10 f), C6 H3 -3,5-(CF3 )2 (10 g), CH3 (11); E=O (12), S (13)) are discussed. The solid state structures of four alkynes and two complexes are reported. (Spectro)electrochemical studies show a moderate influence of the nature of the heteroatom and the electron-donating or -withdrawing substituents R in 10 a-g on the electrochemical and spectroscopic properties. The CVs display two consecutive one-electron redox events with ΔE°'=350-495 mV. A linear relationship between ΔE°' and the σp Hammett constant for 10 a-f was found. IR, UV/Vis/NIR and EPR studies for 10(+) -13(+) confirm full charge delocalization over the {Ru}CH-CH-heterocycle-CH-CH{Ru} backbone, classifying them as Class III systems according to the Robin and Day classification. DFT-optimized structures of the neutral complexes agree well with the experimental ones and provide insight into the structural consequences of stepwise oxidations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Advanced Test Reactor Core Modeling Update Project Annual Report for Fiscal Year 2012

    Energy Technology Data Exchange (ETDEWEB)

    David W. Nigg, Principal Investigator; Kevin A. Steuhm, Project Manager

    2012-09-01

    depletion HELIOS calculations for all ATR cycles since August 2009, Cycle 145A through Cycle 151B, was successfully completed during 2012. This major effort supported a decision late in the year to proceed with the phased incorporation of the HELIOS methodology into the ATR Core Safety Analysis Package (CSAP) preparation process, in parallel with the established PDQ-based methodology, beginning late in Fiscal Year 2012. Acquisition of the advanced SERPENT (VTT-Finland) and MC21 (DOE-NR) Monte Carlo stochastic neutronics simulation codes was also initiated during the year and some initial applications of SERPENT to ATRC experiment analysis were demonstrated. These two new codes will offer significant additional capability, including the possibility of full-3D Monte Carlo fuel management support capabilities for the ATR at some point in the future. Finally, a capability for rigorous sensitivity analysis and uncertainty quantification based on the TSUNAMI system has been implemented and initial computational results have been obtained. This capability will have many applications as a tool for understanding the margins of uncertainty in the new models as well as for validation experiment design and interpretation.

  6. MICHIGAN/INDIANA: Siberian Snakes strike again

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Full text: Siberian snakes are showing themselves to be even more deadly than expected in killing their prey, the depolarizing resonances which would make it very difficult to accelerate polarized protons to TeV energies at accelerators such as the Tevatron, UNK, LHC, and SSC. The snake concept was proposed in the mid-1970s by Siberians Yaroslav Derbenev and Anatoly Kondratenko at Novosibirsk, but the snakes lay almost dormant until Owen Chamberlain, Ernest Courant, Alan Krisch, and the late Kent Terwilliger organized the 1985 Superconducting Supercollider (SSC) polarized beam workshop in Ann Arbor, which highlighted the need to test the concept. The idea is to rotate the spin through 180° on each turn in the ring. With such successive spin flips, the depolarizing effects seen in one turn should be cancelled by an equal and opposite perturbation on the subsequent turn. The new Cooler Ring at the Indiana University Cyclotron Facility then seemed an excellent test site for these eager but untested serpents. The Michigan/lndiana/Brookhaven team led by Krisch constructed the world's first snake and found that it could easily overcome its initial enemy, the imperfection depolarizing resonances caused by ring magnet imperfections (January/February 1990, page 20). In the next few years the growing team of ''herpetologists'' showed that Siberian snakes could overcome all kinds of depolarizing resonances, including the intrinsic kind (caused by the vertical betatron oscillations which keep the beam focused) and the synchrotron resonances (caused by synchrotron oscillations in energy). The team also discovered a new type of snake that was inadvertently built into the cooling section. This socalled type-3 snake rotates the spin around the vertical direction. A full type-1 snake (such as the team's superconducting solenoid magnet) rotates the spin by 180° around the beam direction; a type-2 snake rotates the spin around the radial direction

  7. Epidemiology of snakebite accidents in the municipalities of the state of Paraíba, Brazil Epidemiologia dos acidentes ofídicos ocorridos nos municípios do Estado da Paraíba, Brasil

    Directory of Open Access Journals (Sweden)

    Rafaella Moreno Barros

    2013-05-01

    Full Text Available Accidents involving venomous animals represent an important, albeit neglected, public health issue worldwide. A descriptive study was made of snakebite cases attended and recorded between 2007 and 2010 in the health units of the municipalities of Cariri, State of Paraíba, northeastern Brazil. Data was collected from the Injury Notification Information System data banks of the Health Ministry and a total of 351 records of snakebite victims were reviewed. Victims were predominantly male farm workers over 50. The highest incidence of snakebites occurred in rural areas, between April and June of 2007 and 2010. Snakes of the genus Bothrops were responsible for most cases, and victims were mostly bitten on the feet. The majority of the victims received medical assistance within 1 to 3 hours after being bitten. The most common clinical manifestations were pain, edema and ecchymosis, which were mainly classified as mild or moderate. Two deaths were reported. It was concluded that there is a significant impact of seasonality in snakebites, the prevalence of attacks caused by Bothrops, affecting the lower limbs of adult male farmers in rural areas. The findings of this study may contribute to identify the conditions that increase the risk of snake attacks in the northeastern region.Acidentes por animais peçonhentos representam um importante, embora negligenciado, problema de saúde pública mundial. Neste sentido, foi realizado um estudo descritivo dos acidentes ofídicos atendidos e registrados, entre 2007 e 2010, nas unidades de saúde dos municípios do Cariri, Estado da Paraíba, Nordeste do Brasil. As informações foram coletadas do banco de dados do Sistema de Informação de Agravos de Notificação do Ministério da Saúde. Um total de 351 registros de vítimas de ataques por serpentes peçonhentas foram analisados. As vítimas foram predominantemente trabalhadores rurais do sexo masculino com mais de 50 anos. As maiores incidências de

  8. Protistas "incerta sedis" de ofídios do Brasil: Toddia França, 1912 e Pirhemocyton Chatton & Blanc, 1914: estudo comparativo "Incerta sedis" Portists from Brazilian snakes: Toddia França, 1912 and Pirhemocyton Chatton & Blanc, 1914: comparative study

    Directory of Open Access Journals (Sweden)

    Maria Auxiliadora de Sousa

    1973-01-01

    Full Text Available Dentre 683 serpentes procedentes de diferentes pontos do Brasil, 16 (2,4% apresentaram em seu sangue (em glóbulos vermelhos maturos e imaturos Toddia ou Pirhemocyton. Denominamos provisoriamente Toddia os parasitos encontrados em Bothrops moojeni, B. pradoi, B. jararaca e Chironius flavolineatus e Pirhemocyton os encontrados em B. alternatus; fornecemos a primeira referência nestes hospedeiros. Estes parasitos foram estudados comparativamente com o objetivo de estabelecermos a extensão de suas afinidades. Com Toddia de B. moojeni realizamos técnica citoquímica para caracterização de ácidos nucleicos e encontramos positividade apenas para DNA. As maiores afinidades entre os parasitos estudados residiam nas características dos corpúsculos cromáticos e alterações celulares que determinam; observarmos quase total identidade nas maneiras como os parasitos da mesma espécie de serpente se apresentaram. Constatamos a coexistência de inclusões globóides, cristalóides e formas intermediárias associada aos parasitos de B. pradoi e B. alternatus; em C. flavolineatus encotnramos além dos cristais, raríssimas formas intermediárias entre estes e globóides. Afinidades entre Toddia e Pirhemocyton abrangendo o tipo de inclusão contrariam as descrições originais, tornando pouco válida esta separação genérica. Discutimos também os fundamentos da criação das espécies e a possível natureza virótica destes parasitos.Among 683 snakes from several localities of Brazil, 16 (2,4% presented in their blood (in mature or immature red cells Toddia or Pirhemocyton. We named provisorily Toddia the parasites found in Bothrops moojeni, B. pradoi, B. jararaca and Chironius flavolineatus and Pirhemocyton those found in B. alternatus; we give the first reference in these hosts. These parasites were comparatively studied in view to establish the range of their relationship. With Toddia from B. moojeni we attempted nucleic acids by cytochemical

  9. Herpetofauna of an Atlantic rainforest area (Morro São João in Rio de Janeiro State, Brazil

    Directory of Open Access Journals (Sweden)

    Mauricio Almeida-Gomes

    2008-06-01

    Full Text Available We studied the herpetofaunal community from the Atlantic forest of Morro São João, in Rio de Janeiro State, Brazil, and present data on species composition, richness, relative abundance and densities. We combined three sampling methods: plot sampling, visual encounter surveys and pit-fall traps. We recorded sixteen species of amphibians and nine of reptiles. The estimated densities (based on results of plot sampling were 4.5 ind/100 m2 for amphibians and 0.8 ind/100 m² for lizards, and the overall density (amphibians and lizards was 5.3 ind/100 m². For amphibians, Eleutherodactylus and Scinax were the most speciose genera with three species each, and Eleutherodactylus binotatus was the most abundant species (mean density of 3.0 frogs/100 m². The reptile community of Morro São João was dominated by species of the families Gekkonidae and Gymnophtalmidae (Lacertilia and Colubridae (Serpentes. The gymnophtalmid lizard Leposoma scincoides was the most abundant reptile species (mean density of 0.3 ind/100 m². We compare densities obtained in our study data with those of other studied rainforest sites in various tropical regions of the world.Estudamos a comunidade herpetofaunística da Mata Atlântica do Morro São João, Estado do Rio de Janeiro, Brasil, e apresentamos dados da composição, riqueza, abundância relativa e densidade das espécies. Combinamos três metodologias de amostragem: parcelas, encontros visuais e armadilhas de queda. Registramos 16 espécies de anfíbios e 9 espécies de répteis. As densidades estimadas (baseadas nos resultados da amostragem através de parcelas foram 4.5 ind/100 m² para anfíbios, 0.8 ind/100 m² para lagartos, e a densidade total (anfíbios e répteis foi 5.3 ind/100 m². Para anfíbios, Eleutherodactylus e Scinax foram os gêneros com maior número de espécies, com três espécies cada, e Eleutherodactylus binotatus foi a espécie mais abundante (densidade média de 3.0 anuros/100 m². A

  10. Transmutation of Americium in Fast Neutron Facilities

    International Nuclear Information System (INIS)

    Zhang, Youpeng

    2011-01-01

    In this thesis, the feasibility to use a medium sized sodium cooled fast reactor fully loaded with MOX fuel for efficient transmutation of americium is investigated by simulating the safety performance of a BN600-type fast reactor loaded with different fractions of americium in the fuel, using the safety parameters obtained with the SERPENT Monte Carlo code. The focus is on americium mainly due to its long-term contribution to the radiotoxicity of spent nuclear fuel and its deterioration on core's safety parameters. Applying the SAS4A/SASSYS transient analysis code, it is demonstrated that the power rating needs to be reduced by 6% for each percent additional americium introduction into the reference MOX fuel, maintaining 100 K margin to fuel melting, which is the most limiting failure mechanism. Safety analysis of a new Accelerator Driven System design with a smaller pin pitch-to-diameter ratio comparing to the reference EFIT-400 design, aiming at improving neutron source efficiency, was also performed by simulating performance for unprotected loss of flow, unprotected transient overpower, and protected loss-of-heat-sink transients, using neutronic parameters obtained from MCNP calculations. Thanks to the introduction of the austenitic 15/15Ti stainless steel with enhanced creep rupture resistance and acceptable irradiation swelling rate, the suggested ADS design loaded with nitride fuel and cooled by lead-bismuth eutectic could survive the full set of transients, preserving a margin of 130 K to cladding rupture during the most limiting transient. The thesis concludes that efficient transmutation of americium in a medium sized sodium cooled fast reactor loaded with MOX fuel is possible but leads to a severe power penalty. Instead, preserving transmutation rates of minor actinides up to 42 kg/TWh th , the suggested ADS design with enhanced proton source efficiency appears like a better option for americium transmutation

  11. CURRENT BUILDUP IN EMERGING SERPENTINE FLUX TUBES

    International Nuclear Information System (INIS)

    Pariat, E.; Masson, S.; Aulanier, G.

    2009-01-01

    The increase of magnetic flux in the solar atmosphere during active-region formation involves the transport of the magnetic field from the solar convection zone through the lowest layers of the solar atmosphere, through which the plasma β changes from >1 to <1 with altitude. The crossing of this magnetic transition zone requires the magnetic field to adopt a serpentine shape also known as the sea-serpent topology. In the frame of the resistive flux-emergence model, the rising of the magnetic flux is believed to be dynamically driven by a succession of magnetic reconnections which are commonly observed in emerging flux regions as Ellerman bombs. Using a data-driven, three-dimensional (3D) magnetohydrodynamic numerical simulation of flux emergence occurring in active region 10191 on 2002 November 16-17, we study the development of 3D electric current sheets. We show that these currents buildup along the 3D serpentine magnetic-field structure as a result of photospheric diverging horizontal line-tied motions that emulate the observed photospheric evolution. We observe that reconnection can not only develop following a pinching evolution of the serpentine field line, as usually assumed in two-dimensional geometry, but can also result from 3D shearing deformation of the magnetic structure. In addition, we report for the first time on the observation in the UV domain with the Transition Region and Coronal Explorer (TRACE) of extremely transient loop-like features, appearing within the emerging flux domain, which link several Ellermam bombs with one another. We argue that these loop transients can be explained as a consequence of the currents that build up along the serpentine magnetic field.

  12. Isotopic analysis of Bothrops atrox in Amazonian forest

    Science.gov (United States)

    Martinez, M. G.; Silva, A. M.; Chalkidis, H.; de Oliveira Júnior, R. C.; Camargo, P. B.

    2012-12-01

    The poisoning of snakes is considered a public health problem, especially in populations from rural areas of tropical and subtropical countries. In Brazil, the 26,000 snakebites, 90% are of the genus Bothrops, and Bothrops atrox species predominant in the Amazon region including all the Brazilian Amazon. Research shows that using stable isotopes, we can verify the isotopic composition of tissues of animals that depend mainly on food, water ingested and inhaled gases. For this study, samples taken from Bothrops atrox (B. atrox), in forest using pitfall traps and fall ("Pitt-fall traps with drift fence"). The analyzes were performed by mass spectrometry, where the analytical error is 0.3‰ for carbon and 0.5‰ to nitrogen. The results of the forest animals are significantly different from results of animal vivarium. The average values of the tissues and venoms of snakes of the forest for carbon-13 and nitrogen-15 are: δ13C = -24.68‰ and δ15N = 14.22‰ and mean values of tissue and poisons snakes vivarium (Instituto Butantan) to carbon-13 and nitrogen-15 are δ13C = -20.47‰ and δ15N = 8.36‰, with a significantly different due to different sources of food animals. Based on all results isotopic δ13C and δ15N, we can suggest that changes as the power of the serpent, (nature and captivity), changes occur in relation to diet and environment as the means of the isotopic data are quite distinct, showing that these changes can also cause metabolic changes in the body of the animal itself and the different periods of turnover of each tissue analyzed.

  13. Activities of the AZTLAN team on the OECD/Nea benchmark on fast reactors

    Energy Technology Data Exchange (ETDEWEB)

    Lopez S, R.; Gomez T, A.; Puente E, F. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac, Estado de Mexico (Mexico); Del Valle G, E.; Arriaga R, L., E-mail: armando.gomez@inin.gob.mx [IPN, Escuela Superior de Fisica y Matematicas, Av. IPN s/n, 07738 Ciudad de Mexico (Mexico)

    2017-09-15

    In the present paper, the activities of the AZTLAN Platform Fast Reactor Group on the OECD/Nea Benchmark will be described. The main objective of these activities is to test the group staff and capabilities as well as the domestic code reliability by putting them into test in this exercise with different institutions from around the world. Six different core configurations were treated; these are described in two different versions of the Benchmark document. The main tools used by the group were the Finnish stochastic Monte Carlo code Serpent for full core calculations and macroscopic Cross Sections (X S) generation, and the domestic deterministic code AZNHEX for full core calculations. Different calculations were performed, such as full core calculations under nominal conditions, with control rods fully and partially inserted and with the sodium voided in the active zone as well as different reactivity shift values due to various conditions of radial and axial expansion of the fuel elements and structural material. The results obtained in the full core calculations and most of the reactivity shift calculations obtained by our group were indeed comparable to the ones obtained by different institutions when using similar methodologies. Given these favorable results it can be said that the main objective was met and the group showed their capabilities, as well as its possibility to collaborate with other institutes, placing Mexico in a good position in fast reactor analysis. Future work will continue with the calculations not yet treated and with the new core specifications on the new versions of the Benchmark document. (Author)

  14. Modelling of the underwater disposal of uranium mine tailings in Elliot Lake

    International Nuclear Information System (INIS)

    Halbert, B.E.; Scharer, J.M.; Chakravatti, J.L.; Barnes, E.

    1982-01-01

    Underwater disposal of uranium mine tailings from the Elliot Lake area operations offers potential advantages in controlling radon gas release, emission of airborne particulate matter, and acid production from pyrites in the tailings. In addition, the proximity of the three active properties, one owned by Denison Mines Limited and two by Rio Algom Limited, to a large deep lake has spurred interest in the concept. It has been estimated that the placement of approximately 150 million tonnes of tailings from future planned production would occupy less than 20% of the lake volume. To assess the applicability of the underwater tailings disposal concept, a multi-stage study was developed in conjunction with the regulatory agencies. The most important facet identified for investigation during the first-stage investigations was an assessment of the effects of underwater disposal on water quality in the Serpent River Basin watershed. To simulate the effects of underwater disposal, a computer simulation routine was developed and integrated with a water quality model previously developed for the Basin which predicts levels of total dissolved solids, ammonia, dissolved radium-226 and pH. The underwater disposal model component reflects the effects of direct input of tailings into the hypolimnion, the chemical/biological transformation of dissolved constituents in the water column, the reactions of pyritic tailings deposited on the bottom, and the flux of dissolved constituents from the tailings into the water column. To establish site-specific values for the underwater disposal model, field and laboratory experiments were utilized to evaluate rates of pyrite and ammonia oxidation, and pH-alkalinity relationships. The results of these studies and their use in the water quality model are discussed. In addition, the results of two model run simulations are presented. (author)

  15. Sensitivity and Uncertainty Analysis of IAEA CRP HTGR Benchmark Using McCARD

    International Nuclear Information System (INIS)

    Jang, Sang Hoon; Shim, Hyung Jin

    2016-01-01

    The benchmark consists of 4 phases starting from the local standalone modeling (Phase I) to the safety calculation of coupled system with transient situation (Phase IV). As a preliminary study of UAM on HTGR, this paper covers the exercise 1 and 2 of Phase I which defines the unit cell and lattice geometry of MHTGR-350 (General Atomics). The objective of these exercises is to quantify the uncertainty of the multiplication factor induced by perturbing nuclear data as well as to analyze the specific features of HTGR such as double heterogeneity and self-shielding treatment. The uncertainty quantification of IAEA CRP HTGR UAM benchmarks were conducted using first-order AWP method in McCARD. Uncertainty of the multiplication factor was estimated only for the microscopic cross section perturbation. To reduce the computation time and memory shortage, recently implemented uncertainty analysis module in MC wielandt calculation was adjusted. The covariance data of cross section was generated by NJOY/ERRORR module with ENDF/B-VII.1. The numerical result was compared with evaluation result of DeCART/MUSAD code system developed by KAERI. IAEA CRP HTGR UAM benchmark problems were analyzed using McCARD. The numerical results were compared with Serpent for eigenvalue calculation and DeCART/MUSAD for S/U analysis. In eigenvalue calculation, inconsistencies were found in the result with ENDF/B-VII.1 cross section library and it was found to be the effect of thermal scattering data of graphite. As to S/U analysis, McCARD results matched well with DeCART/MUSAD, but showed some discrepancy in 238U capture regarding implicit uncertainty.

  16. Plant chimeras: The good, the bad, and the 'Bizzaria'.

    Science.gov (United States)

    Frank, Margaret H; Chitwood, Daniel H

    2016-11-01

    Chimeras - organisms that are composed of cells of more than one genotype - captured the human imagination long before they were formally described and used in the laboratory. These organisms owe their namesake to a fire-breathing monster from Greek mythology that has the head of a lion, the body of a goat, and the tail of a serpent. The first description of a non-fictional chimera dates back to the middle of the seventeenth century when the Florentine gardener Pietro Nati discovered an adventitious shoot growing from the graft junction between sour orange (Citrus aurantium) and citron (Citrus medica). This perplexing chimera that grows with sectors phenotypically resembling each of the citrus progenitors inspired discussion and wonder from the scientific community and was fittingly named the 'Bizzaria'. Initially, the 'Bizzaria' was believed to be an asexual hybrid that formed from a cellular fusion between the grafted parents; however, in-depth cellular analyses carried out centuries later demonstrated that the 'Bizzaria', along with other chimeras, owe their unique sectored appearance to a conglomeration of cells from the two donors. Since this pivotal discovery at the turn of the twentieth century, chimeras have served both as tools and as unique biological phenomena that have contributed to our understanding of plant development at the cellular, tissue, and organismal level. Rapid advancements in genome sequencing technologies have enabled the establishment of new model species with novel morphological and developmental features that enable the generation of chimeric organisms. In this review, we show that genetic mosaic and chimera studies provide a technologically simple way to delve into the organismal, genetic, and genomic inner workings underlying the development of diverse model organisms. Moreover, we discuss the unique opportunity that chimeras present to explore universal principles governing intercellular communication and the coordination of

  17. Feasibility Study of Core Design with a Monte Carlo Code for APR1400 Initial core

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jinsun; Chang, Do Ik; Seong, Kibong [KEPCO NF, Daejeon (Korea, Republic of)

    2014-10-15

    The Monte Carlo calculation becomes more popular and useful nowadays due to the rapid progress in computing power and parallel calculation techniques. There have been many attempts to analyze a commercial core by Monte Carlo transport code using the enhanced computer capability, recently. In this paper, Monte Carlo calculation of APR1400 initial core has been performed and the results are compared with the calculation results of conventional deterministic code to find out the feasibility of core design using Monte Carlo code. SERPENT, a 3D continuous-energy Monte Carlo reactor physics burnup calculation code is used for this purpose and the KARMA-ASTRA code system, which is used for a deterministic code of comparison. The preliminary investigation for the feasibility of commercial core design with Monte Carlo code was performed in this study. Simplified core geometry modeling was performed for the reactor core surroundings and reactor coolant model is based on two region model. The reactivity difference at HZP ARO condition between Monte Carlo code and the deterministic code is consistent with each other and the reactivity difference during the depletion could be reduced by adopting the realistic moderator temperature. The reactivity difference calculated at HFP, BOC, ARO equilibrium condition was 180 ±9 pcm, with axial moderator temperature of a deterministic code. The computing time will be a significant burden at this time for the application of Monte Carlo code to the commercial core design even with the application of parallel computing because numerous core simulations are required for actual loading pattern search. One of the remedy will be a combination of Monte Carlo code and the deterministic code to generate the physics data. The comparison of physics parameters with sophisticated moderator temperature modeling and depletion will be performed for a further study.

  18. Acidentes por animais peçonhentos no Estado do Tocantins: aspectos clínico-epidemiológicos

    Directory of Open Access Journals (Sweden)

    Gustavo Fernandes Leobas

    2016-05-01

    Full Text Available Accidents by venomous animals are the second cause of human poisoning in Brazil, second only to drug intoxication. Nationally the scorpions are most responsible for this event, but there is regional variation according to different degrees of human occupation and habitat of the animals involved. This study examined the envenomations in Tocantins State in the years 2010 and 2011, with the aim of identifying clinical and epidemiological aspects related to this condition. The data were collected from the Notifiable Diseases Information System (SINAN and related to rainfall characteristics of the region. It was used the BioEstat 5.0® software to check the statistical validity of the data by the chi-square test, defined an α = 5%. Of all the victims, 69.0% were male and 50.0% were aged between 20 and 49 years. Most accidents occurred during the rainy season and in the countryside (58.9%, environment where men were three times more affected than women. The bite was most frequent in the foot (40.5%, hand (15.7% and leg (12.2%, demonstrating that the use of proper footwear, gloves and leggings may represent important protective measure. Snakes caused the most injuries (50.9%, followed by scorpions (19.7%. Pain and swelling were the main local clinical manifestations reported, and secondary infection the most frequent local complication. Ten deaths were recorded in the period, all by the bite of serpents. These data show that the main victims of such accidents in the State are young men coming from rural areas, hit in the body’s extremities, especially during the rainy season.

  19. High conversion Th-U{sup 233} fuel assembly for current generation of PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Baldova, D.; Fridman, E. [Reactor Safety Div., Helmholtz-Zentrum Dresden-Rossendorf, POB 510119, Dresden, 01314 (Germany)

    2012-07-01

    This paper presents a preliminary design of a high conversion Th-U{sup 233} fuel assembly applicable for current generation of Pressurized Water Reactor (PWRs). The considered fuel assembly has a typical 17 x 17 PWR lattice. However in order to increase the conversion of Th{sup 232} to U{sup 233}, the assembly was subdivided into the two regions called seed and blanket. The central seed region has a higher than blanket U{sup 233} content and acts as a neutron source for the peripheral blanket region. The latest acts as a U{sup 233} breeder. While the seed fuel pins have a standard dimensions the blanket fuel radius was increased in order to reduce the moderation and to facilitate the resonance neutron absorption in blanket Th{sup 232}. The U{sup 233} content in the seed and blanket regions was optimized to achieve maximal initial to discharged fissile inventory ratio (FIR) taking into account the target fuel cycle length of 12 months with 3-batch reloading scheme. In this study the neutronic calculations were performed on the fuel assembly level using Helios deterministic lattice transport code. The fuel cycle length and the core k{sub eff} were estimated by applying the Non Linear Reactivity Model. The applicability of the HELIOS code for the analysis of the Th-based high conversion designs was confirmed with the help of continuous-energy Monte-Carlo code SERPENT. The results of optimization studies show that for the heterogeneous seed and blanket (SB) fuel assembly the FIR of about 0.95 can be achieved. (authors)

  20. Responses of terrestrial herpetofauna to persistent, novel ecosystems resulting from mountaintop removal mining

    Science.gov (United States)

    Williams, Jennifer M.; Brown, Donald J.; Wood, Petra B.

    2017-01-01

    Mountaintop removal mining is a large-scale surface mining technique that removes entire floral and faunal communities, along with soil horizons located above coal seams. In West Virginia, the majority of this mining occurs on forested mountaintops. However, after mining ceases the land is typically reclaimed to grasslands and shrublands, resulting in novel ecosystems. In this study, we examined responses of herpetofauna to these novel ecosystems 10–28 y postreclamation. We quantified differences in species-specific habitat associations, (sub)order-level abundances, and habitat characteristics in four habitat types: reclaimed grassland, reclaimed shrubland, forest fragments in mined areas, and nonmined intact forest. Habitat type accounted for 33.2% of the variation in species-specific captures. With few exceptions, forest specialists were associated with intact forest and fragmented forest sites, while habitat generalists were either associated with grassland and shrubland sites or were distributed among all habitat types. At the (sub)order level, salamander (Order Urodela) captures were highest at fragmented and intact forest sites, frog and toad (Order Anura) captures were lowest at intact forest sites, and snake (Suborder Serpentes) captures were highest at shrubland sites. Habitat type was a strong predictor for estimated total abundance of urodeles, but not for anurans or snakes. Tree stem densities in grasslands differed from the other three habitat types, and large trees (>38 cm diameter at breast height) were only present at forest sites. Overstory vegetation cover was greater in forested than in reclaimed habitat types. Ground cover in reclaimed grasslands was distinct from forest treatments with generally less woody debris and litter cover and more vegetative cover. It is important to consider the distributions of habitat specialists of conservation concern when delineating potential mountaintop mine sites, as these sites will likely contain unsuitable

  1. Prediction of Fission Product Release during the LOFC Experiments at the HTTR

    International Nuclear Information System (INIS)

    Shi, D.; Xhonneux, A.; Verfondern, K.; Ueta, S.; Allelein, H.-J.

    2014-01-01

    Demonstration tests were conducted using the High Temperature Engineering Test Reactor (HTTR) in Oarai, Japan, to confirm the safety of HTGR technologies and assure the expected physical phenomena to occur under given conditions. As part of the OECD directed LOFC (“loss of forced cooling”) project, a series of three tests at the HTTR has been planned with tripping of all gas circulators while deactivating all reactor reactivity control to disallow reactor scram due to abnormal reduction of primary coolant flow rate. The tests fall into anticipated transient without scram (ATWS) with occurrence of reactor recriticality. They serve the important purpose to provide a valuable data base for the validation of computer models regarding neutronics, heat transfer and fluid dynamics, fuel performance and fission product transport and release behavior in HTGRs. The Source Term Analysis Code System (STACY) is a new code development at the Research Center Jülich encompassing the original verified and validated computer models for simulating fission product transport and release. For verification of the modernized and extended version, it was assured that results obtained with the original tools could be reproduced. One of the new features of STACY is its ability to also treat fuel compacts of (full) cylindrical or annular shape and a complete prismatic block reactor core, respectively, supposed sufficient input data be available. The paper will describe the new STACY tool and present the results of fission product behavior in the HTTR core under the LOFC test conditions. Calculations are based on time-dependent neutronics and fluid dynamics results obtained with the Serpent and MGT models. (author)

  2. Integration of the TNXYZ computer program inside the platform Salome; Integracion del programa de computo TNXYZ dentro de la plataforma Salome

    Energy Technology Data Exchange (ETDEWEB)

    Chaparro V, F. J.

    2014-07-01

    The present work shows the procedure carried out to integrate the code TNXYZ as a calculation tool at the graphical simulation platform Salome. The TNXYZ code propose a numerical solution of the neutron transport equation, in several groups of energy, steady-state and three-dimensional geometry. In order to discretized the variables of the transport equation, the code uses the method of discrete ordinates for the angular variable, and a nodal method for the spatial dependence. The Salome platform is a graphical environment designed for building, editing and simulating mechanical models mainly focused on the industry and unlike other software, in order to form a complete scheme of pre and post processing of information, to integrate and control an external source code. Before the integration the in the Salome platform TNXYZ code was upgraded. TNXYZ was programmed in the 90s using Fortran 77 compiler; for this reason the code was adapted to the characteristics of the current Fortran compilers; in addition, with the intention of extracting partial results over the process sequence, the original structure of the program underwent a modularization process, i.e. the main program was divided into sections where the code performs major operations. This procedure is controlled by the information module (YACS) on Salome platform, and it could be useful for a subsequent coupling with thermal-hydraulics codes. Finally, with the help of the Monte Carlo code Serpent several study cases were defined in order to check the process of integration; the verification process consisted in performing a comparison of the results obtained with the code executed as stand-alone and after modernized, integrated and controlled by the Salome platform. (Author)

  3. Comparison of square and hexagonal fuel lattices for high conversion PWRs

    International Nuclear Information System (INIS)

    Kotlyar, D.; Shwageraus, E.

    2011-01-01

    This paper reports on an investigation into fuel design choices of a PWR operating in a self sustainable Th- 233 U fuel cycle. Achieving such self-sustainable with respect to fissile material fuel cycle would practically eliminate concerns over nuclear fuel supply hundreds of years into the future. Moreover, utilization of light water reactor technology and its associated vast experience would allow faster deployment of such fuel cycle without immediate need for development of fast reactor technology, which tends to be more complex and costly. In order to evaluate feasibility of this concept, two types of fuel assembly lattices were considered: square and hexagonal. The hexagonal lattice may offer some advantages over the square one. For example, the fertile blanket fuel can be packed more tightly reducing the blanket volume fraction in the core and potentially allowing to achieve higher core average power density. Furthermore, hexagonal lattice may allow more uniform leakage of neutrons from fissile to fertile regions and therefore more uniform neutron captures in thorium blanket. The calculations were carried out with Monte-Carlo based BGCore system, which includes neutronic, fuel depletion and thermo-hydraulic modules. The results were compared to those obtained from Serpent Monte-Carlo code and deterministic fuel assembly transport code BOXER. One of the major design challenges associated with the square seed-blanket concept is high power peaking due to the high concentration of fissile material in the seed region. In order to explore feasibility of the studied designs, the calculations were extended to include 3D fuel assembly analysis with thermal-hydraulic feedback. The coupled neutronic - thermal-hydraulic calculations were performed with BGCore code system. The analysis showed that both hexagonal and square seed-blanket fuel assembly designs have a potential of achieving net breeding. While no major neutronic advantages were observed for either fuel

  4. A Conceptual Study of a Supercritical CO2-Cooled Micro Modular Reactor

    Directory of Open Access Journals (Sweden)

    Hwanyeal Yu

    2015-12-01

    Full Text Available A neutronics conceptual study of a supercritical CO2-cooled micro modular reactor (MMR has been performed in this work. The suggested MMR is an extremely compact and truck-transportable nuclear reactor. The thermal power of the MMR is 36.2 MWth and it is designed to have a 20-year lifetime without refueling. A salient feature of the MMR is that all the components including the generator are integrated in a small reactor vessel. For a minimal volume and long lifetime of the MMR core, a fast neutron spectrum is utilized in this work. To enhance neutron economy and maximize the fuel volume fraction in the core, a high-density uranium mono-nitride U15N fuel is used in the fast-spectrum MMR. Unlike the conventional supercritical CO2-cooled fast reactors, a replaceable fixed absorber (RFA is introduced in a unique way to minimize the excess reactivity and the power peaking factor of the core. For a compact core design, the drum-type control absorber is adopted as the primary reactivity control mechanism. In this study, the neutronics analyses and depletions have been performed by using the continuous energy Monte Carlo Serpent code with the evaluated nuclear data file ENDF/B-VII.1 Library. The MMR core is characterized in view of several important safety parameters such as control system worth, fuel temperature coefficient (FTC and coolant void reactivity (CVR, etc. In addition, a preliminary thermal-hydraulic analysis has also been performed for the hottest channel of the Korea Advanced Institute of Science and Technology (KAIST MMR.

  5. Effect of the Target Motion Sampling Temperature Treatment Method on the Statistics and Performance

    Science.gov (United States)

    Viitanen, Tuomas; Leppänen, Jaakko

    2014-06-01

    Target Motion Sampling (TMS) is a stochastic on-the-fly temperature treatment technique that is being developed as a part of the Monte Carlo reactor physics code Serpent. The method provides for modeling of arbitrary temperatures in continuous-energy Monte Carlo tracking routines with only one set of cross sections stored in the computer memory. Previously, only the performance of the TMS method in terms of CPU time per transported neutron has been discussed. Since the effective cross sections are not calculated at any point of a transport simulation with TMS, reaction rate estimators must be scored using sampled cross sections, which is expected to increase the variances and, consequently, to decrease the figures-of-merit. This paper examines the effects of the TMS on the statistics and performance in practical calculations involving reaction rate estimation with collision estimators. Against all expectations it turned out that the usage of sampled response values has no practical effect on the performance of reaction rate estimators when using TMS with elevated basis cross section temperatures (EBT), i.e. the usual way. With 0 Kelvin cross sections a significant increase in the variances of capture rate estimators was observed right below the energy region of unresolved resonances, but at these energies the figures-of-merit could be increased using a simple resampling technique to decrease the variances of the responses. It was, however, noticed that the usage of the TMS method increases the statistical deviances of all estimators, including the flux estimator, by tens of percents in the vicinity of very strong resonances. This effect is actually not related to the usage of sampled responses, but is instead an inherent property of the TMS tracking method and concerns both EBT and 0 K calculations.

  6. First Results for Fluid Dynamics, Neutronics and Fission Product Behaviour in HTR applying the HTR Code Package (HCP) Prototype

    International Nuclear Information System (INIS)

    Allelein, H.-J.; Kasselmann, S.; Xhonneux, A.; Lambertz, D.

    2014-01-01

    To simulate the different aspects of High Temperature Reactor (HTR) cores, a variety of specialized computer codes have been developed at Forschungszentrum Jülich (IEK-6) and Aachen University (LRST) in the last decades. In order to preserve knowledge, to overcome present limitations and to make these codes applicable to modern computer clusters, these individual programs are being integrated into a consistent code package. The so-called HTR code package (HCP) couples the related and recently applied physics models in a highly integrated manner and therefore allows to simulate phenomena with higher precision in space and time while at the same time applying state-of-the-art programming techniques and standards. This paper provides an overview of the status of the HCP and reports about first benchmark results for an HCP prototype which couples the fluid dynamics and time dependent neutronics code MGT-3D, the burn up code TNT and the fission product release code STACY. Due to the coupling of MGT-3D and TNT, a first step towards a new reactor operation and accident simulation code was made, where nuclide concentrations calculated by TNT are fed back into a new spectrum code of the HCP. Selected operation scenarios of the HTR-Module 200 concept plant and the HTTR were chosen to be simulated with the HCP prototype. The fission product release during normal operation conditions will be calculated with STACY based on a core status derived from SERPENT and MGT–3D. Comparisons will be shown against data generated by the legacy codes VSOP99/11, NAKURE and FRESCO-II. (author)

  7. Hybrid microscopic depletion model in nodal code DYN3D

    International Nuclear Information System (INIS)

    Bilodid, Y.; Kotlyar, D.; Shwageraus, E.; Fridman, E.; Kliem, S.

    2016-01-01

    Highlights: • A new hybrid method of accounting for spectral history effects is proposed. • Local concentrations of over 1000 nuclides are calculated using micro depletion. • The new method is implemented in nodal code DYN3D and verified. - Abstract: The paper presents a general hybrid method that combines the micro-depletion technique with correction of micro- and macro-diffusion parameters to account for the spectral history effects. The fuel in a core is subjected to time- and space-dependent operational conditions (e.g. coolant density), which cannot be predicted in advance. However, lattice codes assume some average conditions to generate cross sections (XS) for nodal diffusion codes such as DYN3D. Deviation of local operational history from average conditions leads to accumulation of errors in XS, which is referred as spectral history effects. Various methods to account for the spectral history effects, such as spectral index, burnup-averaged operational parameters and micro-depletion, were implemented in some nodal codes. Recently, an alternative method, which characterizes fuel depletion state by burnup and 239 Pu concentration (denoted as Pu-correction) was proposed, implemented in nodal code DYN3D and verified for a wide range of history effects. The method is computationally efficient, however, it has applicability limitations. The current study seeks to improve the accuracy and applicability range of Pu-correction method. The proposed hybrid method combines the micro-depletion method with a XS characterization technique similar to the Pu-correction method. The method was implemented in DYN3D and verified on multiple test cases. The results obtained with DYN3D were compared to those obtained with Monte Carlo code Serpent, which was also used to generate the XS. The observed differences are within the statistical uncertainties.

  8. Hydrogen Isotope Measurements of Organic Acids and Alcohols by Pyrolysis-GC-MS-TC-IRMS: Application to Analysis of Experimentally Derived Hydrothermal Mineral-Catalyzed Organic Products

    Science.gov (United States)

    Socki, Richard A.; Fu, Qi; Niles, Paul B.; Gibson, Everett K., Jr.

    2012-01-01

    We report results of experiments to measure the H isotope composition of organic acids and alcohols. These experiments make use of a pyroprobe interfaced with a GC and high temperature extraction furnace to make quantitative H isotope measurements. This work compliments our previous work that focused on the extraction and analysis of C isotopes from the same compounds [1]. Together with our carbon isotope analyses our experiments serve as a "proof of concept" for making C and H isotope measurements on more complex mixtures of organic compounds on mineral surfaces in abiotic hydrocarbon formation processes at elevated temperatures and pressures. Our motivation for undertaking this work stems from observations of methane detected within the Martian atmosphere [2-5], coupled with evidence showing extensive water-rock interaction during Mars history [6-8]. Methane production on Mars could be the result of synthesis by mineral surface-catalyzed reduction of CO2 and/or CO by Fischer-Tropsch Type (FTT) reactions during serpentization [9,10]. Others have conducted experimental studies to show that FTT reactions are plausible mechanisms for low-molecular weight hydrocarbon formation in hydrothermal systems at mid-ocean ridges [11-13]. Our H isotope measurements utilize an analytical technique combining Pyrolysis-Gas Chromatograph-Mass Spectrometry-High Temperature Conversion-Isotope Ratio Mass Spectrometry (Py-GC-MS-TC-IRMS). This technique is designed to carry a split of the pyrolyzed GC-separated product to a Thermo DSQII quadrupole mass spectrometer as a means of making qualitative and semi-quantitative compositional measurements of separated organic compounds, therefore both chemical and isotopic measurements can be carried out simultaneously on the same sample.

  9. Chimeric creatures in Greek mythology and reflections in science.

    Science.gov (United States)

    Bazopoulou-Kyrkanidou, E

    2001-04-15

    "The Chimaera" in Homer's Iliad, "was of divine stock, not of men, in the forepart a lion, in the hinder a serpent, and in the midst a goat, ellipsis Bellerophon slew her, trusting in the signs of the gods." In Hesiod's Theogony it is emphasized that "Chimaera ellipsis had three heads, one of a grim-eyed lion, another of a goat, and another of a snakeellipsis". In addition to this interspecies animal chimera, human/animal chimeras are referred to in Greek mythology, preeminent among them the Centaurs and the Minotaur. The Centaurs, as horse/men, first appear in Geometric and early Archaic art, but in the literature not until early in the fifth century B.C. The bullheaded-man Minotaur, who is not certainly attested in the literary evidence until circa 500 B.C., first appears in art about 650 B.C. Attempts, in the fourth century B.C. and thereafter, to rationalize their mythical appearance were in vain; their chimeric nature retained its fascinating and archetypal form over the centuries. Early in the 1980s, experimental sheep/goat chimeras were produced removing the reproductive barrier between these two animal species. Late in the 1990s, legal, political, ethical, and moral fights loomed over a patent bid on human/animal chimeras. Chimeric technology is recently developed; however, the concept of chimerism has existed in literary and artistic form in ancient mythology. This is yet another example where art and literature precede scientific research and development. Copyright 2001 Wiley-Liss. Inc.

  10. Isotopic change in the tissues of Bothrops atrox in captivity collected from environments of the eastern Amazon

    Science.gov (United States)

    Martinez, M. G.; Chalkidis, H. D.; Amazonas, D. R.; da Silva, A. M.; De Oliveira, R., Jr.; Camargo, P. B.

    2013-12-01

    The Bothrops atrox is little studied because it is sympatric Amazonian animals, and very little is known about the ecology and natural history of this species. It has a generalist diet and the distribution of this species is very wide. The adult animals forage mostly on the ground, while the younger animals prefer to stay on the vegetation. They are easily find in the rainy months in areas near lakes and seasonally flooded and are difficult to find in the driest months, a period where there is less availability of preys in these environments. Due to its aggressiveness, is considered one of the most feared snakes in South America and in the eastern Amazon, being responsible for the largest number of snakebites in the region. Through stable isotope carbon-13 and nitrogen-15, is intended to characterize the variations of the feeding habits of these collected animals in different environments and also when they are kept in captivity, feeding the animal's bioterium. The serpents were collected in environments with different land uses, such as native forest, savannah, pasture and have been brought to the serpentarium Integrated College Tapajos (FIT), being retained in order to Samplings throughout the experiment with feeding mice's own bioterium. When these snakes came from different locations, samples were collected scales and blood (T0), before receiving the new supply (captive), and every time we fed the mice the vivarium, new tissue samples were collected, (T1, T2, T3) to exchange all the nature of food for the food captivity.Based on the results of δ13C and δ15N, the samples collected in the tissues of snakes of different environments (nature and captivity), it was observed that changes in food sources reflect changes in tissues (blood and scales), also reflecting the production of poison different periods of turnover of absorbed material in those tissues, contributing to the study of animal ecology and behavior in relation to habitat.

  11. In Memoriam doctora Nelly Carrillo Tarazona de Espinoza (1927-2017

    Directory of Open Access Journals (Sweden)

    Javier Icochea Monteza

    2017-10-01

    Full Text Available La doctora Nelly Carrillo Tarazona de Espinoza, falleció el 12 de agosto del 2017. Nació en Chiquián, provincia de Bolognesi en el departamento de Ancash el 2 de noviembre de 1927. Estudió ciencias biológicas en la Escuela Instituto de Ciencias Biológicas, Facultad de Ciencias de la Universidad Nacional Mayor de San Marcos (UNMSM, egresando en el año 1950, año a partir del cual la UNMSM comenzó a otorgar el título de Biólogo. Sustento su tesis doctoral en la UNMSM en 1973, titulada “Una nueva especie del género Sibynomorphus (Serpentes: Colubridae”. La doctora Carrillo dedico sus investigaciones al estudio de anfibios y reptiles. Ella fue discípula inmediata de Jehan Vellard, médico de nacionalidad francesa que contribuyó al desarrollo y ampliación de los estudios herpetológicos y del Laboratorio de Herpetología del Museo de Historia Natural de la Universidad Nacional Mayor de San Marcos. Posteriormente, la doctora Carrillo continuaría con el desarrollo de esta linea de investigación desempeñándose como Jefa del Departamento de Herpetología durante más de 25 años, consagrando sus esfuerzos al cuidado y mantenimiento de la importante colección científica de dicho departamento.

  12. Tsetse immune system maturation requires the presence of obligate symbionts in larvae.

    Directory of Open Access Journals (Sweden)

    Brian L Weiss

    2011-05-01

    Full Text Available Beneficial microbial symbionts serve important functions within their hosts, including dietary supplementation and maintenance of immune system homeostasis. Little is known about the mechanisms that enable these bacteria to induce specific host phenotypes during development and into adulthood. Here we used the tsetse fly, Glossina morsitans, and its obligate mutualist, Wigglesworthia glossinidia, to investigate the co-evolutionary adaptations that influence the development of host physiological processes. Wigglesworthia is maternally transmitted to tsetse's intrauterine larvae through milk gland secretions. We can produce flies that lack Wigglesworthia (Gmm(Wgm- yet retain their other symbiotic microbes. Such offspring give rise to adults that exhibit a largely normal phenotype, with the exception being that they are reproductively sterile. Our results indicate that when reared under normal environmental conditions Gmm(Wgm- adults are also immuno-compromised and highly susceptible to hemocoelic E. coli infections while age-matched wild-type individuals are refractory. Adults that lack Wigglesworthia during larval development exhibit exceptionally compromised cellular and humoral immune responses following microbial challenge, including reduced expression of genes that encode antimicrobial peptides (cecropin and attacin, hemocyte-mediated processes (thioester-containing proteins 2 and 4 and prophenoloxidase, and signal-mediating molecules (inducible nitric oxide synthase. Furthermore, Gmm(Wgm- adults harbor a reduced population of sessile and circulating hemocytes, a phenomenon that likely results from a significant decrease in larval expression of serpent and lozenge, both of which are associated with the process of early hemocyte differentiation. Our results demonstrate that Wigglesworthia must be present during the development of immature progeny in order for the immune system to function properly in adult tsetse. This phenomenon provides

  13. Sun-Earth Day 2005: Ancient Observatories: Timeless Knowledge

    Science.gov (United States)

    Thieman, J. R.; Cline, T.; Lewis, E.; Hawkins, I.; Odenwald, S.; Mayo, L.

    2005-05-01

    The NASA Sun-Earth Connection Education Forum (SECEF) annually promotes an event called Sun-Earth Day. For Sun-Earth Day 2005 SECEF has selected a theme called "Ancient Observatories: Timeless Knowledge. This year's Sun-Earth Day theme is your ticket to a fascinating journey through time as we explore centuries of sun watching by a great variety of cultures. From ancient solar motion tracking to modern solar activity monitoring the Sun has always occupied an important spot in mankind's quest to understand the Universe. Sun-Earth Day events usually are centered on the spring equinox around March 21, but this year there has already been a webcast from the San Francisco Exploratorium and the Native American ruins at Chaco Canyon, New Mexico on the day of winter solstice 2004. There will be another webcast on March 20 live from Chichen Itza, Mexico highlighting the solar alignment that makes a serpent appear on one of the ancient pyramids. The website http://sunearthday.nasa.gov has been developed to provide the necessary resources and opportunities for participation by scientists and educators in giving school or general public programs about Sun-Earth Day. The goal is to involve as much of the student population and the public in this event as possible and to help them understand the importance of the Sun for ancient and modern peoples. Through engaging activities available on the website, classrooms and museums can create their own event or participate in one of the opportunities we make available. Scientists, educators, amateur astronomers, and museums are invited to register on the website to receive a free packet of materials about Sun-Earth Day for use in making presentations or programs about the event. Past and future Sun-Earth Days will be discussed as well.

  14. PRESENCIA TEOTIHUACANA EN LA CULTURA BOLAÑOS (Teotihuacan Presence in the Bolaños Culture

    Directory of Open Access Journals (Sweden)

    María Teresa Cabrero G.

    2015-09-01

    Full Text Available El cañón de Bolaños fue ocupado durante el periodo prehispánico por un grupo proveniente, posiblemente, del centro de Jalisco, puesto que traían dentro de su bagaje cultural la costumbre de depositar a sus muertos en tumbas de tiro y la construcción de conjuntos circulares como centros ceremoniales. El cañón principia en el altiplano centro-norte y corre hacia el sur hasta desembocar en el río Grande de Santiago en el centro de Jalisco. La presencia de una máscara mortuoria hecha con mosaicos de Spondylus princeps que muestra una nariguera colgante con la representación de una serpiente emplumada y, por otra parte, el descubrimiento de una nariguera con la representación de Tláloc sugieren un contacto con las caravanas teotihuacanas que transitaban a través de la ruta interior de intercambio comercial propuesta por Kelley. ENGLISH: The Bolaños Canyon was occupied during the pre-Hispanic period by a group—possibly coming from the center of Jalisco—as their cultural background included the custom of depositing their dead in shaft tombs and the construction of circular sets as ceremonial centers. The canyon begins in the north central high plateau and flows to the south, ending at the Rio Grande de Santiago in central Jalisco. The presence of a death mask made of Spondylus princeps mosaic, featuring a nose ring pendant with the representation of a feathered serpent and, moreover, the discovery of a nose ring with the representation of Tlaloc, suggest contact with Teotihuacan caravans that traveled through the inland trade route as proposed by Kelley in 1980.

  15. Burnable absorber-integrated Guide Thimble (BigT) - 1. Design concepts and neutronic characterization on the fuel assembly benchmarks

    International Nuclear Information System (INIS)

    Yahya, Mohd-Syukri; Yu, Hwanyeal; Kim, Yonghee

    2016-01-01

    This paper presents the conceptual designs of a new burnable absorber (BA) for the pressurized water reactor (PWR), which is named 'Burnable absorber-integrated Guide Thimble' (BigT). The BigT integrates BA materials into standard guide thimble in a PWR fuel assembly. Neutronic sensitivities and practical design considerations of the BigT concept are points of highlight in the first half of the paper. Specifically, the BigT concepts are characterized in view of its BA material and spatial self-shielding variations. In addition, the BigT replaceability requirement, bottom-end design specifications and thermal-hydraulic considerations are also deliberated. Meanwhile, much of the second half of the paper is devoted to demonstrate practical viability of the BigT absorbers via comparative evaluations against the conventional BA technologies in representative 17x17 and 16x16 fuel assembly lattices. For the 17x17 lattice evaluations, all three BigT variants are benchmarked against Westinghouse's existing BA technologies, while in the 16x16 assembly analyses, the BigT designs are compared against traditional integral gadolinia-urania rod design. All analyses clearly show that the BigT absorbers perform as well as the commercial BA technologies in terms of reactivity and power peaking management. In addition, it has been shown that sufficiently high control rod worth can be obtained with the BigT absorbers in place. All neutronic simulations were completed using the Monte Carlo Serpent code with ENDF/B-VII.0 library. (author)

  16. Integration of the TNXYZ computer program inside the platform Salome

    International Nuclear Information System (INIS)

    Chaparro V, F. J.

    2014-01-01

    The present work shows the procedure carried out to integrate the code TNXYZ as a calculation tool at the graphical simulation platform Salome. The TNXYZ code propose a numerical solution of the neutron transport equation, in several groups of energy, steady-state and three-dimensional geometry. In order to discretized the variables of the transport equation, the code uses the method of discrete ordinates for the angular variable, and a nodal method for the spatial dependence. The Salome platform is a graphical environment designed for building, editing and simulating mechanical models mainly focused on the industry and unlike other software, in order to form a complete scheme of pre and post processing of information, to integrate and control an external source code. Before the integration the in the Salome platform TNXYZ code was upgraded. TNXYZ was programmed in the 90s using Fortran 77 compiler; for this reason the code was adapted to the characteristics of the current Fortran compilers; in addition, with the intention of extracting partial results over the process sequence, the original structure of the program underwent a modularization process, i.e. the main program was divided into sections where the code performs major operations. This procedure is controlled by the information module (YACS) on Salome platform, and it could be useful for a subsequent coupling with thermal-hydraulics codes. Finally, with the help of the Monte Carlo code Serpent several study cases were defined in order to check the process of integration; the verification process consisted in performing a comparison of the results obtained with the code executed as stand-alone and after modernized, integrated and controlled by the Salome platform. (Author)

  17. Répteis e anfíbios de uma região pouco conhecida do sudeste da Amazônia

    Directory of Open Access Journals (Sweden)

    Frederico Gustavo Rodrigues França

    2010-01-01

    Full Text Available Amazônia é a maior floresta tropical do mundo e possui uma enorme biodiversidade. Entretanto, algumas regiões ainda são pouco conhecidas. Este trabalho apresenta um inventário da herpetofauna de uma destas regiões, o município de Boca do Acre, no sudoeste do Amazonas. O inventário foi realizado em dois períodos, uma amostragem durante o meio da estação chuvosa e outra ao final da mesma estação. Diversos métodos foram empregados para as amostragens, como armadilhas de interceptação e queda, procuras visuais diurnas e noturnas, procuras de carro em trechos da BR 317, e registros oportunísticos. Cinqüenta e seis espécies de anfíbios e 53 de répteis foram registradas durante o inventário. Vinte e sete espécies foram capturadas nas armadilhas de interceptação e queda e 38 foram encontradas na BR317, sendo as serpentes o grupo mais impactado por atropelamentos. A curva de acumulação de espécies não atingiu a estabilidade indicando que o inventário não está completo. Os resultados demonstram a grande riqueza de espécies desta região, sua importância para a biodiversidade da Amazônia, e a urgência em sua preservação.

  18. [A history of Korean medical association's emblem: the caduceus of Asklepios and Hermes].

    Science.gov (United States)

    Shin, Young-Jeon

    2007-06-01

    An emblem represents the identity of an organization. Through the emblem of an organization, they differentiate the members from others and reinforce the membership, homogeneity, and pride. It is also a tool that an organization officially publicizes its mission and values. The symbol designed by Cho, Byungduk was announced as the first emblem of Korean Medical Association (KMA) on October 31st 1947. His design work has the caduceus with the Taeguk sign on the top, the symbol of Korea, and the Red Cross in the background including the name, 'KMA'. Since then, the emblem was revised three times: in 1964, 1973, and 1995. The current symbol is based on the design of the first one. Although Asklepian, the single serpent-entwined staff of Asklepios, is the one known as the symbol of medicine, this emblem takes the caduceus of Hermes who is the patron god of merchants, thieves, and travelers. The mistake comes from the unawareness of the distinction between the caduceus of Asklepios and Hermes. Moreover, it proves that U. S. Army Medical Corps (USAMC) heavily influenced the reconstruction of Korean health care system including KMA. The USAMC has used the symbol of caduceus since 1902. In 1947, the year that the first emblem of KMA was established, Southern part of Korea was governed by the United States Military Government (USMG, 1945-1948). The current emblem of KMA brings up a question whether we should continue to use the symbol that was taken from USMAC in the historical period of USMG governance. Celebrating 100th anniversary year of KMA, KMA needs to re-evaluate the appropriateness of the KMA symbol.

  19. A importância dos acidentes ofídicos como causa de mortes em bovinos no Brasil The importance of snake bites as cause of cattle death in Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Hubinger Tokarnia

    2006-06-01

    Full Text Available A revisão da literatura pertinente indica que as opiniões sobre a importância dos acidentes ofídicos, como causa de mortes em bovinos no Brasil, são divergentes no meio veterinário. Enquanto alguns acreditam que são pouco importantes, ou que têm menor significado do que lhes é atribuído, outros são da opinião que esses acidentes são freqüentes. Verificou-se que só foi relatado diagnóstico fundamentado de dois casos fatais de envenenamento por Bothrops spp em bovinos, e de nenhum por Crotalus spp. Um questionário por nós submetido a patologistas e clínicos veterinários que atuam em diversos Estados do país, revelou apenas raros casos suspeitos de envenenamento ofídico fatal em bovinos no Brasil. Em nossas viagens de estudo e nos trabalhos de diagnóstico nunca estabelecemos o diagnóstico de morte por acidente ofídico em bovinos. Os casos tidos como envenenamento ofídico, na sua grande maioria, são apenas suposições, sem embasamento. Esses "diagnósticos", em geral, são feitos à distância dos animais que morreram, à revelia de exame clínico, necropsia e estudo histopatológico. Importante foi a constatação de que, no Brasil, embora algumas serpentes do gênero Bothrops possam, teoricamente, produzir quantidades suficientes de veneno para matar um bovino adulto, em experimentos realizados, apenas Bothrops alternatus foi capaz de levar a morte um dos três bovinos experimentalmente por ela picados; esse animal tinha apenas 279 kg. Já as serpentes do gênero Crotalus poderiam inocular quantidades letais de veneno para bovinos adultos. Mesmo assim, tanto para Bothrops spp, como para Crotalus spp, há que se considerar que as serpentes, em geral, só inoculam parte do veneno disponível. Esse estudo indica que é necessário melhor investigar as mortes suspeitas de terem sido causadas por acidente ofídico em bovinos no Brasil. O estabelecimento do diagnóstico de morte por envenenamento ofídico, porém, só é poss

  20. Composition Optimization of Lithium-Based Ternary Alloy Blankets for Fusion Reactors

    Science.gov (United States)

    Jolodosky, Alejandra

    The goal of this dissertation is to examine the neutronic properties of a novel type of fusion reactor blanket material in the form of lithium-based ternary alloys. Pure liquid lithium, first proposed as a blanket for fusion reactors, is utilized as both a tritium breeder and a coolant. It has many attractive features such as high heat transfer and low corrosion properties, but most importantly, it has a very high tritium solubility and results in very low levels of tritium permeation throughout the facility infrastructure. However, lithium metal vigorously reacts with air and water and presents plant safety concerns including degradation of the concrete containment structure. The work of this thesis began as a collaboration with Lawrence Livermore National Laboratory in an effort to develop a lithium-based ternary alloy that can maintain the beneficial properties of lithium while reducing the reactivity concerns. The first studies down-selected alloys based on the analysis and performance of both neutronic and activation characteristics. First, 3-D Monte Carlo calculations were performed to evaluate two main neutronics performance parameters for the blanket: tritium breeding ratio (TBR), and energy multiplication factor (EMF). Alloys with adequate results based on TBR and EMF calculations were considered for activation analysis. Activation simulations were executed with 50 years of irradiation and 300 years of cooling. It was discovered that bismuth is a poor choice due to achieving the highest decay heat, contact dose rates, and accident doses. In addition, it does not meet the waste disposal ratings (WDR). The straightforward approach to obtain Monte Carlo TBR and EMF results required 231 simulations per alloy and became computationally expensive, time consuming, and inefficient. Consequently, alternate methods were pursued. A collision history-based methodology recently developed for the Monte Carlo code Serpent, calculates perturbation effects on practically

  1. Tentativa de suicídio entre pacientes com uso nocivo de bebidas alcoólicas internados em hospital geral Suicide attempt amongst patients with alcohol misuse admitted to a general hospital

    Directory of Open Access Journals (Sweden)

    Daniela Dantas Lima

    2010-01-01

    Full Text Available OBJETIVO: Detectar fatores associados a histórico de tentativa de suicídio (TS em pacientes internados em hospital geral que fazem uso nocivo de bebidas alcoólicas. MÉTODO: 4.352 pacientes admitidos consecutivamente foram avaliados utilizando-se um rastreamento do qual constavam as escalas AUDIT (Alcohol Use Disorder Identification Test e HAD (Escala Hospitalar de Ansiedade e Depressão. Fixando-se histórico de tentativa de suicídio ao longo da vida como variável dependente, foram realizados testes do qui-quadrado e regressão logística múltipla. RESULTADOS: Uso nocivo de álcool (AUDIT > 8 foi detectado em 423 pacientes. Dentre eles, 60 (14,2% apresentavam sintomas de depressão (HAD > 8 e 34 (8% tinham histórico de TS. Este se associou a ser adulto jovem [razão de chance (RC = 3,4], depressão (RC = 6,6, uso pregresso de psicofármaco (RC = 7 e ter SIDA (RC = 24. CONCLUSÃO: Os resultados fortalecem a necessidade de detectar e tratar adequadamente condições que, combinadas, aumentam consideravelmente o risco de suicídio.OBJECTIVE: To detect factors associated to previous suicide attempt among patients admitted to a general hospital who presented harmful alcohol drinking pattern. METHOD: 4.352 patients consecutively admitted were screened by means of the AUDIT (Alcohol Use Disorder Identification Test and HAD (Hospital Anxiety and Depression Scale. Qui-squared tests and multiple logistic regression were performed. RESULTS: 423 individuals presented alcohol harmful use or dependence (AUDIT > 8, 60 (14.2% of which had depression (HAD > 8 and 34 (8% previous suicide attempt. The latter was more frequent among young adults [odds ratio (OR = 3.4], those who were depressed (OR = 6.6, had previously taken psychotropic medicines (OR = 7 and had AIDS (OR = 24. CONCLUSION: Our findings reinforce the need for detection and adequate treatment of conditions that, when together, strongly increase the suicide risk.

  2. Reductive Elimination Leading to C-C Bond Formation in Gold(III) Complexes: A Mechanistic and Computational Study.

    Science.gov (United States)

    Rocchigiani, Luca; Fernandez-Cestau, Julio; Budzelaar, Peter H M; Bochmann, Manfred

    2018-06-21

    The factors affecting the rates of reductive C-C cross-coupling reactions in gold(III) aryls were studied by using complexes that allow easy access to a series of electronically modified aryl ligands, as well as to gold methyl and vinyl complexes, by using the pincer compounds [(C^N^C)AuR] (R=C 6 F 5 , CH=CMe 2 , Me and p-C 6 H 4 X, where X=OMe, F, H, tBu, Cl, CF 3 , or NO 2 ) as starting materials (C^N^C=2,6-(4'-tBuC 6 H 3 ) 2 pyridine dianion). Protodeauration followed by addition of one equivalent SMe 2 leads to the quantitative generation of the thioether complexes [(C^N-CH)AuR(SMe 2 )] + . Upon addition of a second SMe 2 pyridine is displaced, which triggers the reductive aryl-R elimination. The rates for these cross-couplings increase in the sequence k(vinyl)>k(aryl)≫k(C 6 F 5 )>k(Me). Vinyl-aryl coupling is particularly fast, 1.15×10 -3  L mol -1  s -1 at 221 K, whereas both C 6 F 5 and Me couplings encountered higher barriers for the C-C bond forming step. The use of P(p-tol) 3 in place of SMe 2 greatly accelerates the C-C couplings. Computational modelling shows that in the C^N-bonded compounds displacement of N by a donor L is required before the aryl ligands can adopt a conformation suitable for C-C bond formation, so that elimination takes place from a four-coordinate intermediate. The C-C bond formation is the rate-limiting step. In the non-chelating case, reductive C(sp 2 )-C(sp 2 ) elimination from three-coordinate ions [(Ar 1 )(Ar 2 )AuL] + is almost barrier-free, particularly if L=phosphine. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Insatisfação com a imagem corporal e fatores associados em universitários Body Image dissatisfaction and associated factors among college students

    Directory of Open Access Journals (Sweden)

    Cilene Rebolho Martins

    2012-08-01

    Full Text Available O objetivo deste estudo foi analisar a insatisfação com a imagem corporal e verificar a associação com o estado nutricional e variáveis sociodemográficas (sexo, faixa etária, turno de estudo e trabalho remunerado em universitários. Participaram do estudo 865 universitários. A prevalência de insatisfação com a imagem corporal foi de 77,9% e as variáveis associadas a este desfecho foram sexo e estado nutricional (avaliado pelo IMC com base em dados autorreferidos. Os homens apresentaram mais frequentemente o desejo de aumentar o peso e as mulheres, de reduzir. Universitários com excesso de peso demonstraram maior desejo de reduzir o peso corporal (RC = 6,83; IC-95% = 3,72-12,54, e aqueles com baixo peso apresentaram mais chance de desejar aumentar (RC = 3,06; IC-95% = 1,59-5,88. Destaca-se a importância de promover ações de incentivo à prática de atividades físicas e à adoção de hábitos alimentares saudáveis, bem como a prevenção de comportamentos de risco adotados no sentido de modificara imagem corporal.The objective of this study was to analyze the body image dissatisfaction and its association with nutritional status and socio-demographics variables (sex, age group, period of study and paid employment among college students. The study involved 865 college students. The prevalence of body image dissatisfaction was 77.9%and sex and nutritional status (assessed by body mass index based on self-reported measures were associated with this outcome. Men, more often, desired to increase body weight and women, to reduce it. Overweight college students were more likely to desire to reduce body weight (OR = 6.83; 95% CI = 3.72-12.54, and those who were underweight were more likely to desire to increase it (OR = 3.06; 95% CI = 1.59-5.88. Thus, it is highlighted the importance of policy to promote physical activity practices and adoption of healthy eating habits, as well as to prevent risk behaviors adopted to change the body

  4. Serpentinization and carbonation of pristine continental ultramafic rocks and applications to the oceanic crust; H2O-CO2 alteration of dunites and re-distribution of Ni-Cu-PGE in sulphide deposits

    Science.gov (United States)

    Grant, Thomas; McEnroe, Suzanne; Eske Sørensen, Bjørn; Larsen, Rune; Pastore, Zeudia; Rune Grannes, Kim; Nikolaisen, Even

    2017-04-01

    Here, we document carbonation and serpentinization within a suite of ultramafic rocks from a continental setting. These ultramafic rocks vary from pristine dunites to varying degrees of serpentinization which locally penetrates the ultramafic complex. Hence, it allows us to observe a number of delicate serpentinization and carbonation reactions, otherwise lost during more extensive alteration or tectonic events. We use a multi-disciplinary approach using petrographic, EPMA, thermodynamic modelling and geophysical data to reveal how the initial stages of serpentization and carbonation in dunites affects the distribution of economic to sub-economic deposits of Ni-Cu and PGE. The data can then be applied to oceanic crust. The samples are dunites and poikilitic wehrlites from the Reinfjord Ultramafic complex, Seiland Igneous Province Northern Norway. The complex formed through crystallization of picritic melts in the lower continental crust. The dunites contain small amounts of interstitial clinopyroxene, sulphides and spinel, with local enrichments in Ni, Cu and PGE. Late magmatic CO2-H2O-S fluids reacted with the dunite forming clots of amphibole + dolomite + sulphides + enstatite, reaction rims of enstatite + dolomite, and inclusions trails of dolomite + enstatite + magnetite + CO2 fluid. Thermodynamic modelling reveals that these textures formed at pressures of >12 kbar and temperatures 850-950 °C, which would be consistent with the late magmatic history of the Reinfjord complex. The clots and reactions have local association with enrichments in gold-rich PGMs. A second stage of alteration involved H2O-dominated fluids. These formed predominantly lizardite serpentinization, as is often concentrated within highly localized fracture zones. Thermodynamic modelling shows that these formed serpentinization interacted with the earlier formed carbonate bearing assemblages leading to the formation of serpentinite, native copper and symplectites of brucite + calcite. The

  5. Elimination of Guinea Worm Disease in Ethiopia; Current Status of the Disease's, Eradication Strategies and Challenges to the End Game.

    Science.gov (United States)

    Beyene, Habtamu Bedimo; Bekele, Abyot; Shifara, Amanu; Ebstie, Yehenew A; Desalegn, Zelalem; Kebede, Zeyede; Mulugeta, Abate; Deribe, Kebede; Tadesse, Zerihun; Abebe, Tamrat; Kebede, Biruck; Abrha, Getaneh; Jima, Daddi

    2017-01-01

    Dracunculiasis, also named Guinea Worm Disease (GWD), is one of the Neglected Tropical Diseases (NTDs) caused by a parasitic nematode known as Dracunculus medinensis and has been known since antiquity as 'fiery serpent' from Israelites. It is transmitted to humans via drinking contaminated water containing infective copepods. Given, its feasibility for eradication, the Guinea Worm Eradication Program (GWEP) was launched in 1980 with the aim of eradicating the disease. Since its inception, GWEP has made an extraordinary progress in interrupting transmission. Globally, the number of reported cases reduced from 3.5 million in 20 countries in 1986 to only 22 cases in 2015 from only four countries namely South Sudan, Mali, Chad and Ethiopia. Since Mali has interrupted transmission of GWD in 2016, currently, the disease remains endemic in only three sub-Saharan African countries namely, South Sudan, Chad and Ethiopia. Each endemic country has its own national Guinea Worm Eradication Program. In Ethiopia, the Ethiopian Dracunculiasis Eradication Program (EDEP) which was established in 1993 has made remarkable move towards interruption of disease transmission and now the endgame is fast approaching. The EDEP with support mainly from The Carter Center, WHO, and UNICEF has reduced GWD by more than 99% from 1994 to 2015. In 2015, only 3 indigenous cases in humans and 14 in animals (13 in dogs and 1 in baboon) were reported. In 2016, 3 human cases, 14 dogs and 2 baboon infections were reported.. Refugee influx from the Republic of South Sudan (RSS), increased animal infections with unknown role in transmission of Dracunculiasis, the presence of hard to reach communities and lack of safe water sources in remote non-village areas remain among important challenges at this final stage of GWD eradication in Ethiopia. This paper reviews progress made towards Guinea Worm Eradication with a focus on the experience of the Ethiopian Dracunculiasis Eradication Program (EDEP), and

  6. Proteomics and antivenomics of Papuan black snake (Pseudechis papuanus) venom with analysis of its toxicological profile and the preclinical efficacy of Australian antivenoms.

    Science.gov (United States)

    Pla, Davinia; Bande, Benjamin W; Welton, Ronelle E; Paiva, Owen K; Sanz, Libia; Segura, Álvaro; Wright, Christine E; Calvete, Juan J; Gutiérrez, José María; Williams, David J

    2017-01-06

    The Papuan black snake (Pseudechis papuanus Serpentes: Elapidae) is endemic to Papua New Guinea, Indonesian Papua and Australia's Torres Strait Islands. We have investigated the biological activity and proteomic composition of its venom. The P. papuanus venom proteome is dominated by a variety (n≥18) of PLA 2 s, which together account for ~90% of the venom proteins, and a set of low relative abundance proteins, including a short-neurotoxic 3FTx (3.1%), 3-4 PIII-SVMPs (2.8%), 3 cysteine-rich secretory proteins (CRISP; 2.3%) 1-3 l-amino acid oxidase (LAAO) molecules (1.6%). Probing of a P. papuanus cDNA library with specific primers resulted in the elucidation of the full-length nucleotide sequences of six new toxins, including vespryn and NGF not found in the venom proteome, and a calglandulin protein involved in toxin expression with the venom glands. Intravenous injection of P. papuanus venom in mice induced lethality, intravascular haemolysis, pulmonary congestion and oedema, and anticoagulation after intravenous injection, and these effects are mainly due to the action of PLA 2 s. This study also evaluated the in vivo preclinical efficacy of Australian black snake and polyvalent Seqirus antivenoms. These antivenoms were effective in neutralising the lethal, PLA 2 and anticoagulant activities of P. papuanus venom in mice. On the other hand, all of the Seqirus antivenoms tested using an antivenomic approach exhibited strong immunorecognition of all the venom components. These preclinical results suggest that Australian Seqirus 1 antivenoms may provide paraspecific protection against P. papuanus venom in humans. The toxicological profile and proteomic composition of the venom of the Papuan black snake, Pseudechis papuanus, a large diurnal snake endemic to the southern coast of New Guinea and a handful of close offshore islands, were investigated. Intravenous injection of P. papuanus venom in mice induced intravascular hemolysis, pulmonary congestion and edema

  7. High conversion pressurized water reactor with boiling channels

    Energy Technology Data Exchange (ETDEWEB)

    Margulis, M., E-mail: maratm@post.bgu.ac.il [The Unit of Nuclear Engineering, Ben Gurion University of the Negev, POB 653, Beer Sheva 84105 (Israel); Shwageraus, E., E-mail: es607@cam.ac.uk [Department of Engineering, University of Cambridge, CB2 1PZ Cambridge (United Kingdom)

    2015-10-15

    Highlights: • Conceptual design of partially boiling PWR core was proposed and studied. • Self-sustainable Th–{sup 233}U fuel cycle was utilized in this study. • Seed-blanket fuel assembly lattice optimization was performed. • A coupled Monte Carlo, fuel depletion and thermal-hydraulics studies were carried out. • Thermal–hydraulic analysis assured that the design matches imposed safety constraints. - Abstract: Parametric studies have been performed on a seed-blanket Th–{sup 233}U fuel configuration in a pressurized water reactor (PWR) with boiling channels to achieve high conversion ratio. Previous studies on seed-blanket concepts suggested substantial reduction in the core power density is needed in order to operate under nominal PWR system conditions. Boiling flow regime in the seed region allows more heat to be removed for a given coolant mass flow rate, which in turn, may potentially allow increasing the power density of the core. In addition, reduced moderation improves the breeding performance. A two-dimensional design optimization study was carried out with BOXER and SERPENT codes in order to determine the most attractive fuel assembly configuration that would ensure breeding. Effects of various parameters, such as void fraction, blanket fuel form, number of seed pins and their dimensions, on the conversion ratio were examined. The obtained results, for which the power density was set to be 104 W/cm{sup 3}, created a map of potentially feasible designs. It was found that several options have the potential to achieve end of life fissile inventory ratio above unity, which implies potential feasibility of a self-sustainable Thorium fuel cycle in PWRs without significant reduction in the core power density. Finally, a preliminary three-dimensional coupled neutronic and thermal–hydraulic analysis for a single seed-blanket fuel assembly was performed. The results indicate that axial void distribution changes drastically with burnup. Therefore

  8. A multi-physics analysis for the actuation of the SSS in opal reactor

    Directory of Open Access Journals (Sweden)

    Ferraro Diego

    2018-01-01

    Full Text Available OPAL is a 20 MWth multi-purpose open-pool type Research Reactor located at Lucas Heights, Australia. It was designed, built and commissioned by INVAP between 2000 and 2006 and it has been operated by the Australia Nuclear Science and Technology Organization (ANSTO showing a very good overall performance. On November 2016, OPAL reached 10 years of continuous operation, becoming one of the most reliable and available in its kind worldwide, with an unbeaten record of being fully operational 307 days a year. One of the enhanced safety features present in this state-of-art reactor is the availability of an independent, diverse and redundant Second Shutdown System (SSS, which consists in the drainage of the heavy water reflector contained in the Reflector Vessel. As far as high quality experimental data is available from reactor commissioning and operation stages and even from early component design validation stages, several models both regarding neutronic and thermo-hydraulic approaches have been developed during recent years using advanced calculations tools and the novel capabilities to couple them. These advanced models were developed in order to assess the capability of such codes to simulate and predict complex behaviours and develop highly detail analysis. In this framework, INVAP developed a three-dimensional CFD model that represents the detailed hydraulic behaviour of the Second Shutdown System for an actuation scenario, where the heavy water drainage 3D temporal profiles inside the Reflector Vessel can be obtained. This model was validated, comparing the computational results with experimental measurements performed in a real-size physical model built by INVAP during early OPAL design engineering stages. Furthermore, detailed 3D Serpent Monte Carlo models are also available, which have been already validated with experimental data from reactor commissioning and operating cycles. In the present work the neutronic and thermohydraulic

  9. A multi-physics analysis for the actuation of the SSS in opal reactor

    Science.gov (United States)

    Ferraro, Diego; Alberto, Patricio; Villarino, Eduardo; Doval, Alicia

    2018-05-01

    OPAL is a 20 MWth multi-purpose open-pool type Research Reactor located at Lucas Heights, Australia. It was designed, built and commissioned by INVAP between 2000 and 2006 and it has been operated by the Australia Nuclear Science and Technology Organization (ANSTO) showing a very good overall performance. On November 2016, OPAL reached 10 years of continuous operation, becoming one of the most reliable and available in its kind worldwide, with an unbeaten record of being fully operational 307 days a year. One of the enhanced safety features present in this state-of-art reactor is the availability of an independent, diverse and redundant Second Shutdown System (SSS), which consists in the drainage of the heavy water reflector contained in the Reflector Vessel. As far as high quality experimental data is available from reactor commissioning and operation stages and even from early component design validation stages, several models both regarding neutronic and thermo-hydraulic approaches have been developed during recent years using advanced calculations tools and the novel capabilities to couple them. These advanced models were developed in order to assess the capability of such codes to simulate and predict complex behaviours and develop highly detail analysis. In this framework, INVAP developed a three-dimensional CFD model that represents the detailed hydraulic behaviour of the Second Shutdown System for an actuation scenario, where the heavy water drainage 3D temporal profiles inside the Reflector Vessel can be obtained. This model was validated, comparing the computational results with experimental measurements performed in a real-size physical model built by INVAP during early OPAL design engineering stages. Furthermore, detailed 3D Serpent Monte Carlo models are also available, which have been already validated with experimental data from reactor commissioning and operating cycles. In the present work the neutronic and thermohydraulic models, available for

  10. Transient Simulation of the Multi-SERTTA Experiment with MAMMOTH

    International Nuclear Information System (INIS)

    Ortensi, Javier; Baker, Benjamin; Wang, Yaqi; Schunert, Sebastian; DeHart, Mark

    2017-01-01

    This work details the MAMMOTH reactor physics simulations of the Static Environment Rodlet Transient Test Apparatus (SERTTA) conducted at Idaho National Laboratory in FY-2017. TREAT static-environment experiment vehicles are being developed to enable transient testing of Pressurized Water Reactor (PWR) type fuel specimens, including fuel concepts with enhanced accident tolerance (Accident Tolerant Fuels, ATF). The MAMMOTH simulations include point reactor kinetics as well as spatial dynamics for a temperature-limited transient. The strongly coupled multi-physics solutions of the neutron flux and temperature fields are second order accurate both in the spatial and temporal domains. MAMMOTH produces pellet stack powers that are within 1.5% of the Monte Carlo reference solutions. Some discrepancies between the MCNP model used in the design of the flux collars and the Serpent/MAMMOTH models lead to higher power and energy deposition values in Multi-SERTTA unit 1. The TREAT core results compare well with the safety case computed with point reactor kinetics in RELAP5-3D. The reactor period is 44 msec, which corresponds to a reactivity insertion of 2.685% delta k/k$. The peak core power in the spatial dynamics simulation is 431 MW, which the point kinetics model over-predicts by 12%. The pulse width at half the maximum power is 0.177 sec. Subtle transient effects are apparent at the beginning insertion in the experimental samples due to the control rod removal. Additional difference due to transient effects are observed in the sample powers and enthalpy. The time dependence of the power coupling factor (PCF) is calculated for the various fuel stacks of the Multi-SERTTA vehicle. Sample temperatures in excess of 3100 K, the melting point UO$ 2 $, are computed with the adiabatic heat transfer model. The planned shaped-transient might introduce additional effects that cannot be predicted with PRK models. Future modeling will be focused on the shaped-transient by improving the

  11. Effect of the Target Motion Sampling temperature treatment method on the statistics and performance

    International Nuclear Information System (INIS)

    Viitanen, Tuomas; Leppänen, Jaakko

    2015-01-01

    Highlights: • Use of the Target Motion Sampling (TMS) method with collision estimators is studied. • The expected values of the estimators agree with NJOY-based reference. • In most practical cases also the variances of the estimators are unaffected by TMS. • Transport calculation slow-down due to TMS dominates the impact on figures-of-merit. - Abstract: Target Motion Sampling (TMS) is a stochastic on-the-fly temperature treatment technique that is being developed as a part of the Monte Carlo reactor physics code Serpent. The method provides for modeling of arbitrary temperatures in continuous-energy Monte Carlo tracking routines with only one set of cross sections stored in the computer memory. Previously, only the performance of the TMS method in terms of CPU time per transported neutron has been discussed. Since the effective cross sections are not calculated at any point of a transport simulation with TMS, reaction rate estimators must be scored using sampled cross sections, which is expected to increase the variances and, consequently, to decrease the figures-of-merit. This paper examines the effects of the TMS on the statistics and performance in practical calculations involving reaction rate estimation with collision estimators. Against all expectations it turned out that the usage of sampled response values has no practical effect on the performance of reaction rate estimators when using TMS with elevated basis cross section temperatures (EBT), i.e. the usual way. With 0 Kelvin cross sections a significant increase in the variances of capture rate estimators was observed right below the energy region of unresolved resonances, but at these energies the figures-of-merit could be increased using a simple resampling technique to decrease the variances of the responses. It was, however, noticed that the usage of the TMS method increases the statistical deviances of all estimators, including the flux estimator, by tens of percents in the vicinity of very

  12. Results for Phase I of the IAEA Coordinated Research Program on HTGR Uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Strydom, Gerhard [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bostelmann, Friederike [Idaho National Lab. (INL), Idaho Falls, ID (United States); Yoon, Su Jong [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-01-01

    results. The status on the Monte Carlo modeling of the experimental VHTRC facility is also discussed. Reference results were obtained for the neutronics stand-alone cases (Ex. I-1 and Ex. I-2) using the (relatively new) Monte Carlo code Serpent, and comparisons were performed with the more established Monte Carlo codes MCNP and KENO-VI. For the thermal-fluids stand-alone cases (Ex. I-3 and I-4) the commercial CFD code CFX was utilized to obtain reference results that can be compared with lower fidelity tools.

  13. Self-sustained detachment observed in LHD and comparison with detachment and Marfe in W7-AS

    International Nuclear Information System (INIS)

    Miyazawa, J.; Masuzaki, S.; Yamada, H.; Sakamoto, R.; Peterson, B. J.; Shoji, M.; Ohyabu, N.; Komori, A.; Motojima, O.

    2005-01-01

    One of the crucial issues for a magnetically confined fusion reactor [1-3] is the reduction of the divertor heat load. Edge plasma cooling by increasing the density or introducing impurities such as neon as radiators is effective for reducing the divertor heat load by detaching the plasma from the divertor plates. In high-density tokamak plasmas, the so-called high-recycling regime is predicted by two-point model [4,5], where the divertor temperature (density) nonlinearly decreases (increases) with the main plasma density. Detachment takes place when the density is increased further. Then, the pressure in the flux tube is no longer conserved due to the increased radiation loss, charge exchange loss, and volume recombination. Eventually, the discharge is terminated by disruption often via rapid formation of a radiation condensation Marfe [5,6]. This scenario well explains the experimental results of tokamaks [5,7]. A similar kind of conventional detachment has been also intensively studied in a stellarator, W7-AS, after modification to the island divertor configuration [8,9]. Detachment in W7-AS is achieved by increasing the density beyond the density threshold for the high-density H-mode (HDH) [10]. As the density is increased further to the operational density limit, complete detachment takes place and, in some cases, the Marfe is formed on (or inside of) the last-closed-flux-surface (LCFS) [11-13]. These are reviewed in Section 4. Recently, a new state of self-sustained detachment has been found in LHD and named the Serpens mode (Self-regulated plasma edge neath the last-closed-flux-surface) [15,16]. In the Serpens mode, the hot plasma boundary is shrinking to equal 90 % of the LCFS radius. Large fluctuations appear in the divertor flux, H alpha and Cm signals, together with a rotating radiation belt named the serpent [17]. Detachment in LHD is observed in a significant decrease in the ion saturation current, Isat, measured on the divertor tiles [18,19]. In this

  14. Utilização de Placas de polipropileno e fios de náilon na técnica de fixação espinhal segmentar modificada em uma jibóia Polypropylene plates and nylon suture in a modified technique of segmental spinal fixation in a redtail boa

    Directory of Open Access Journals (Sweden)

    Simone Borges Salgueiro De Simone

    2011-05-01

    Full Text Available Um exemplar adulto de Boa constrictor com histórico de atropelamento foi atendido no Hospital Veterinário. Exames clínico e radiográfico identificaram a presença de uma luxação no terço médio da coluna vertebral. O paciente foi submetido à estabilização cirúrgica da lesão, em que se avaliou a eficácia de uma variação da técnica de fixação espinhal segmentar modificada. O segmento foi estabilizado através da fixação e placas plásticas sob forma de hemicerclagem nos corpos vertebrais, com auxílio de fio de náilon n. 0 e a síntese tecidual finalizou o procedimento. No pós-operatório, instituiu-se a antibioticoterapia, curativos locais diários e restrição de espaço até a cicatrização total do ferimento. A variação da técnica mostrou ser eficaz no realinhamento e estabilização anatômica da luxação do segmento vertebral para a serpente em questão.An adult exemplar of Boa constrictor with a history of overthrowing was send to the Veterinary Hospital. Clinical and radiographic examinations identified the presence of a dislocation in the third middle of the spine. The patient was submitted to a surgical correction of the lesion, which evaluated the effectiveness of a variation of the modified technique of segmental spinal fixation. The segment was stabilized by fixing plastic plates in the form of hemicerclage in the vertebral bodies, with nylon n.0, and tissue synthesis completed the procedure. Postoperatively, it was instituted antibiotic therapy, daily curatives and space restrictions until the complete healing of the wound. The variation of the technique has proved to be safe and effective for the snake of this study, promoting the realignment and stabilization of the anatomical vertebral segment.

  15. Uso de cetamina pela via cólon-retal para contenção química de jiboias Boa constrictor Linnaeus, 1758 com teste de influência da droga sobre o sistema renal

    Directory of Open Access Journals (Sweden)

    Tatiale O. Rodrigues

    Full Text Available RESUMO: Por serem frequentes na clínica de animais silvestres, faz-se necessária a manipulação de jiboias e para isso, indispensável o conhecimento sobre as manobras precisas para o tratamento das possíveis afecções. Quando se opta pela contenção química, ou pela realização de procedimentos cirúrgicos, um dos fármacos utilizados na anestesia de serpentes é a cetamina. Viu-se a necessidade de buscar uma via alternativa, semelhante em eficácia às tradicionais para a contenção química, porém que minimizasse os riscos e efeitos adversos encontrados na sua execução. O presente trabalho sugere que a via retal seja esta alternativa, por isso, treze jiboias foram submetidas à administração de 70mg/kg de cloridrato de cetamina, com sonda uretral, através da cloaca até o cólon-reto. Foram avaliados, nos tempos 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 e 120 minutos, a partir da administração do fármaco, os seguintes parâmetros: frequência cardíaca, relaxamento muscular e mobilidade, resistência à contenção ou manipulação e reação postural de endireitamento. Foi realizada coleta de 0,5mL de sangue por punção do seio venoso paravertebral cervical, antes da administração do fármaco, no dia seguinte e após nove dias. Foram dosadas as concentrações plasmáticas de cálcio, fósforo e ácido úrico de todos os exemplares a fim de verificar o perfil bioquímico renal e avaliar a influência do fármaco neste sistema. Não foram observadas alterações bioquímicas plasmáticas durante o período de avaliação. Foi possível promover a contenção química das jiboias Boa constrictor, utilizando cloridrato de cetamina pela via cólon-retal.

  16. Development of neutronic models for the thermal hydraulics coupling of the MSFR and the calculation of effective kinetic parameters

    International Nuclear Information System (INIS)

    Laureau, Axel

    2015-01-01

    In this PhD thesis, we describe the development of innovative neutronic models for their coupling with thermal hydraulics such that they combine precision and reasonable computational times. One of the main cases where this method is applied is the Molten Salt Fast Reactor (MSFR) whose combines a fast neutron spectrum with a thorium cycle. In this fourth generation reactor, the motion of the delayed neutron precursors and the associated phenomena have to be taken into account due to the liquid fuel circulation. The starting point for these developments was the preliminary design of this type of system where a dedicated multi-physical representation was needed to study the reactor performance in steady and transient conditions. As a first step, a stationary coupling was developed. A neutronic model based on a stochastic approach was associated to a CFD (Computational Fluid Dynamics) code to solve the Navier Stokes equations for turbulent flows and the transport of the delayed neutron precursors. The impact of this precursor motion is taken into account by reconstructing the prompt shower that they generate. This approach, called by shower, views the critical reactor as a prompt subcritical reactor that amplifies a source of delayed neutrons. A second step consisted in developing a neutronic model based on a time dependent version of the fission matrices (Transient Fission Matrix or TFM) so as to enable reactor transient studies. With the TFM model, an initial computation of the matrices with a stochastic code (MCNP, SERPENT) allows the characterization of the global spatial and time dependent neutronic response of the reactor with a precision close to that of a Monte Carlo calculation. The information thus obtained is then used to calculate transients, while retaining the advantage of reduced computational time. The TFM model, which can be used for various system concepts, also allows the evaluation of effective kinetic parameters such as the effective fraction of

  17. Condensation and homogenization of cross sections for the deterministic transport codes with Monte Carlo method: Application to the GEN IV fast neutron reactors

    International Nuclear Information System (INIS)

    Cai, Li

    2014-01-01

    In the framework of the Generation IV reactors neutronic research, new core calculation tools are implemented in the code system APOLLO3 for the deterministic part. These calculation methods are based on the discretization concept of nuclear energy data (named multi-group and are generally produced by deterministic codes) and should be validated and qualified with respect to some Monte-Carlo reference calculations. This thesis aims to develop an alternative technique of producing multi-group nuclear properties by a Monte-Carlo code (TRIPOLI-4). At first, after having tested the existing homogenization and condensation functionalities with better precision obtained nowadays, some inconsistencies are revealed. Several new multi-group parameters estimators are developed and validated for TRIPOLI-4 code with the aid of itself, since it has the possibility to use the multi-group constants in a core calculation. Secondly, the scattering anisotropy effect which is necessary for handling neutron leakage case is studied. A correction technique concerning the diagonal line of the first order moment of the scattering matrix is proposed. This is named the IGSC technique and is based on the usage of an approximate current which is introduced by Todorova. An improvement of this IGSC technique is then presented for the geometries which hold an important heterogeneity property. This improvement uses a more accurate current quantity which is the projection on the abscissa X. The later current can represent the real situation better but is limited to 1D geometries. Finally, a B1 leakage model is implemented in the TRIPOLI-4 code for generating multi-group cross sections with a fundamental mode based critical spectrum. This leakage model is analyzed and validated rigorously by the comparison with other codes: Serpent and ECCO, as well as an analytical case.The whole development work introduced in TRIPOLI-4 code allows producing multi-group constants which can then be used in the core

  18. Bilan des introductions récentes d'amphibiens et de reptiles dans les milieux aquatiques continentaux de France métropolitaine

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    HAFFNER P.

    1997-01-01

    Full Text Available En France métropolitaine, on dénombre actuellement 36 amphibiens et 33 reptiles se reproduisant régulièrement. A deux exceptions près, les amphibiens de la faune française sont aquatiques. En revanche, seules quatre espèces de reptiles (2 tortues et 2 serpents fréquentent très régulièrement ou exclusivement les milieux aquatiques. Les introductions en milieux aquatiques effectuées depuis le début du siècle ne concernent qu'une vingtaine d'espèces d'amphibiens ou de reptiles. Le discoglosse peint (Discoglossus pictus et la grenouille taureau (Rana catesbeiana sont les deux seules espèces étrangères dont l'introduction a conduit à une naturalisation. La tortue de «Floride» (Trachemys scripta elegans pourrait bien suivre prochainement la même voie. Certaines espèces françaises ont, par contre, été introduites avec succès en métropole, hors de leurs aires d'indigénat. Les causes connues de ces introductions sont liées à des opérations à but économique (commerce, à caractère socioculturel (loisirs ou à fondement scientifique (expériences. Ces opérations n'ont cependant généralement pas pour but l'introduction volontaire d'une espèce dans le milieu naturel, celle-ci résultant plutôt de négligences. Certaines introductions involontaires ont pu aussi avoir pour origine un transport passif (par exemple, par voie maritime. Des conséquences négatives de ces introductions sont suspectées, mais ne sont généralement pas démontrées. Elles peuvent s'inscrire dans les catégories suivantes : compétition avec une espèce autochtone, prédation excessive sur une ou plusieurs espèces autochtones, pollution génétique, introduction de maladies ou de parasites.

  19. Uncertainty Propagation Analysis for the Monte Carlo Time-Dependent Simulations

    International Nuclear Information System (INIS)

    Shaukata, Nadeem; Shim, Hyung Jin

    2015-01-01

    In this paper, a conventional method to control the neutron population for super-critical systems is implemented. Instead of considering the cycles, the simulation is divided in time intervals. At the end of each time interval, neutron population control is applied on the banked neutrons. Randomly selected neutrons are discarded, until the size of neutron population matches the initial neutron histories at the beginning of time simulation. A time-dependent simulation mode has also been implemented in the development version of SERPENT 2 Monte Carlo code. In this mode, sequential population control mechanism has been proposed for modeling of prompt super-critical systems. A Monte Carlo method has been properly used in TART code for dynamic criticality calculations. For super-critical systems, the neutron population is allowed to grow over a period of time. The neutron population is uniformly combed to return it to the neutron population started with at the beginning of time boundary. In this study, conventional time-dependent Monte Carlo (TDMC) algorithm is implemented. There is an exponential growth of neutron population in estimation of neutron density tally for super-critical systems and the number of neutrons being tracked exceed the memory of the computer. In order to control this exponential growth at the end of each time boundary, a conventional time cut-off controlling population strategy is included in TDMC. A scale factor is introduced to tally the desired neutron density at the end of each time boundary. The main purpose of this paper is the quantification of uncertainty propagation in neutron densities at the end of each time boundary for super-critical systems. This uncertainty is caused by the uncertainty resulting from the introduction of scale factor. The effectiveness of TDMC is examined for one-group infinite homogeneous problem (the rod model) and two-group infinite homogeneous problem. The desired neutron density is tallied by the introduction of

  20. Uncertainty Propagation Analysis for the Monte Carlo Time-Dependent Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Shaukata, Nadeem; Shim, Hyung Jin [Seoul National University, Seoul (Korea, Republic of)

    2015-10-15

    In this paper, a conventional method to control the neutron population for super-critical systems is implemented. Instead of considering the cycles, the simulation is divided in time intervals. At the end of each time interval, neutron population control is applied on the banked neutrons. Randomly selected neutrons are discarded, until the size of neutron population matches the initial neutron histories at the beginning of time simulation. A time-dependent simulation mode has also been implemented in the development version of SERPENT 2 Monte Carlo code. In this mode, sequential population control mechanism has been proposed for modeling of prompt super-critical systems. A Monte Carlo method has been properly used in TART code for dynamic criticality calculations. For super-critical systems, the neutron population is allowed to grow over a period of time. The neutron population is uniformly combed to return it to the neutron population started with at the beginning of time boundary. In this study, conventional time-dependent Monte Carlo (TDMC) algorithm is implemented. There is an exponential growth of neutron population in estimation of neutron density tally for super-critical systems and the number of neutrons being tracked exceed the memory of the computer. In order to control this exponential growth at the end of each time boundary, a conventional time cut-off controlling population strategy is included in TDMC. A scale factor is introduced to tally the desired neutron density at the end of each time boundary. The main purpose of this paper is the quantification of uncertainty propagation in neutron densities at the end of each time boundary for super-critical systems. This uncertainty is caused by the uncertainty resulting from the introduction of scale factor. The effectiveness of TDMC is examined for one-group infinite homogeneous problem (the rod model) and two-group infinite homogeneous problem. The desired neutron density is tallied by the introduction of