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Sample records for bone-eating worms osedax

  1. A remarkable diversity of bone-eating worms (Osedax; Siboglinidae; Annelida

    Directory of Open Access Journals (Sweden)

    Johnson Shannon B

    2009-11-01

    Full Text Available Abstract Background Bone-eating Osedax worms have proved to be surprisingly diverse and widespread. Including the initial description of this genus in 2004, five species that live at depths between 25 and 3,000 m in the eastern and western Pacific and in the north Atlantic have been named to date. Here, we provide molecular and morphological evidence for 12 additional evolutionary lineages from Monterey Bay, California. To assess their phylogenetic relationships and possible status as new undescribed species, we examined DNA sequences from two mitochondrial (COI and 16S rRNA and three nuclear genes (H3, 18S and 28S rRNA. Results Phylogenetic analyses identified 17 distinct evolutionary lineages. Levels of sequence divergence among the undescribed lineages were similar to those found among the named species. The 17 lineages clustered into five well-supported clades that also differed for a number of key morphological traits. Attempts to determine the evolutionary age of Osedax depended on prior assumptions about nucleotide substitution rates. According to one scenario involving a molecular clock calibrated for shallow marine invertebrates, Osedax split from its siboglinid relatives about 45 million years ago when archeocete cetaceans first appeared and then diversified during the late Oligocene and early Miocene when toothed and baleen whales appeared. Alternatively, the use of a slower clock calibrated for deep-sea annelids suggested that Osedax split from its siboglinid relatives during the Cretaceous and began to diversify during the Early Paleocene, at least 20 million years before the origin of large marine mammals. Conclusion To help resolve uncertainties about the evolutionary age of Osedax, we suggest that the fossilized bones from Cretaceous marine reptiles and late Oligocene cetaceans be examined for possible trace fossils left by Osedax roots. Regardless of the outcome, the present molecular evidence for strong phylogenetic concordance

  2. Osedax mucofloris (Polychaeta, Siboglinidae, a bone-eating marine worm new to Norway

    Directory of Open Access Journals (Sweden)

    Christoffer Schander

    2010-12-01

    Full Text Available Normal 0 21 false false false NO-BOK X-NONE X-NONE The bone-eating siboglinid polychaete Osedax mucofloris Glover, Källström, Smith & Dahlgren, 2005 is reported from Norwegian waters for the first time. Dense growth was found on bovine bones deposited at 118 meters depth off western Norway. Dwarf males were observed for the first time. The two specimens sequenced were identical to haplotypes previously found at a Swedish whale fall. The possibility of finding additional species of Osedax is discussed.

  3. Bone-Eating Worms Spread: Insights into Shallow-Water Osedax (Annelida, Siboglinidae) from Antarctic, Subantarctic, and Mediterranean Waters.

    Science.gov (United States)

    Taboada, Sergi; Riesgo, Ana; Bas, Maria; Arnedo, Miquel A; Cristobo, Javier; Rouse, Greg W; Avila, Conxita

    2015-01-01

    Osedax, commonly known as bone-eating worms, are unusual marine annelids belonging to Siboglinidae and represent a remarkable example of evolutionary adaptation to a specialized habitat, namely sunken vertebrate bones. Usually, females of these animals live anchored inside bone owing to a ramified root system from an ovisac, and obtain nutrition via symbiosis with Oceanospirillales gamma-proteobacteria. Since their discovery, 26 Osedax operational taxonomic units (OTUs) have been reported from a wide bathymetric range in the Pacific, the North Atlantic, and the Southern Ocean. Using experimentally deployed and naturally occurring bones we report here the presence of Osedax deceptionensis at very shallow-waters in Deception Island (type locality; Antarctica) and at moderate depths near South Georgia Island (Subantarctic). We present molecular evidence in a new phylogenetic analysis based on five concatenated genes (28S rDNA, Histone H3, 18S rDNA, 16S rDNA, and cytochrome c oxidase I-COI-), using Maximum Likelihood and Bayesian inference, supporting the placement of O. deceptionensis as a separate lineage (Clade VI) although its position still remains uncertain. This phylogenetic analysis includes a new unnamed species (O. 'mediterranea') recently discovered in the shallow-water Mediterranean Sea belonging to Osedax Clade I. A timeframe of the diversification of Osedax inferred using a Bayesian framework further suggests that Osedax diverged from other siboglinids during the Middle Cretaceous (ca. 108 Ma) and also indicates that the most recent common ancestor of Osedax extant lineages dates to the Late Cretaceous (ca. 74.8 Ma) concomitantly with large marine reptiles and teleost fishes. We also provide a phylogenetic framework that assigns newly-sequenced Osedax endosymbionts of O. deceptionensis and O. 'mediterranea' to ribospecies Rs1. Molecular analysis for O. deceptionensis also includes a COI-based haplotype network indicating that individuals from Deception

  4. Bone-Eating Worms Spread: Insights into Shallow-Water Osedax (Annelida, Siboglinidae from Antarctic, Subantarctic, and Mediterranean Waters.

    Directory of Open Access Journals (Sweden)

    Sergi Taboada

    Full Text Available Osedax, commonly known as bone-eating worms, are unusual marine annelids belonging to Siboglinidae and represent a remarkable example of evolutionary adaptation to a specialized habitat, namely sunken vertebrate bones. Usually, females of these animals live anchored inside bone owing to a ramified root system from an ovisac, and obtain nutrition via symbiosis with Oceanospirillales gamma-proteobacteria. Since their discovery, 26 Osedax operational taxonomic units (OTUs have been reported from a wide bathymetric range in the Pacific, the North Atlantic, and the Southern Ocean. Using experimentally deployed and naturally occurring bones we report here the presence of Osedax deceptionensis at very shallow-waters in Deception Island (type locality; Antarctica and at moderate depths near South Georgia Island (Subantarctic. We present molecular evidence in a new phylogenetic analysis based on five concatenated genes (28S rDNA, Histone H3, 18S rDNA, 16S rDNA, and cytochrome c oxidase I-COI-, using Maximum Likelihood and Bayesian inference, supporting the placement of O. deceptionensis as a separate lineage (Clade VI although its position still remains uncertain. This phylogenetic analysis includes a new unnamed species (O. 'mediterranea' recently discovered in the shallow-water Mediterranean Sea belonging to Osedax Clade I. A timeframe of the diversification of Osedax inferred using a Bayesian framework further suggests that Osedax diverged from other siboglinids during the Middle Cretaceous (ca. 108 Ma and also indicates that the most recent common ancestor of Osedax extant lineages dates to the Late Cretaceous (ca. 74.8 Ma concomitantly with large marine reptiles and teleost fishes. We also provide a phylogenetic framework that assigns newly-sequenced Osedax endosymbionts of O. deceptionensis and O. 'mediterranea' to ribospecies Rs1. Molecular analysis for O. deceptionensis also includes a COI-based haplotype network indicating that individuals from

  5. Fossil traces of the bone-eating worm Osedax in early Oligocene whale bones

    OpenAIRE

    Kiel, Steffen; Goedert, James L; Kahl, Wolf-Achim; Rouse, Greg W.

    2010-01-01

    Osedax is a recently discovered group of siboglinid annelids that consume bones on the seafloor and whose evolutionary origins have been linked with Cretaceous marine reptiles or to the post-Cretaceous rise of whales. Here we present whale bones from early Oligocene bathyal sediments exposed in Washington State, which show traces similar to those made by Osedax today. The geologic age of these trace fossils (∼30 million years) coincides with the first major radiation of whales, consistent wit...

  6. Bone-eating Osedax worms lived on Mesozoic marine reptile deadfalls.

    Science.gov (United States)

    Danise, Silvia; Higgs, Nicholas D

    2015-04-01

    We report fossil traces of Osedax, a genus of siboglinid annelids that consume the skeletons of sunken vertebrates on the ocean floor, from early-Late Cretaceous (approx. 100 Myr) plesiosaur and sea turtle bones. Although plesiosaurs went extinct at the end-Cretaceous mass extinction (66 Myr), chelonioids survived the event and diversified, and thus provided sustenance for Osedax in the 20 Myr gap preceding the radiation of cetaceans, their main modern food source. This finding shows that marine reptile carcasses, before whales, played a key role in the evolution and dispersal of Osedax and confirms that its generalist ability of colonizing different vertebrate substrates, like fishes and marine birds, besides whale bones, is an ancestral trait. A Cretaceous age for unequivocal Osedax trace fossils also dates back to the Mesozoic the origin of the entire siboglinid family, which includes chemosynthetic tubeworms living at hydrothermal vents and seeps, contrary to phylogenetic estimations of a Late Mesozoic-Cenozoic origin (approx. 50-100 Myr). PMID:25878047

  7. Not whale-fall specialists, Osedax worms also consume fishbones.

    Science.gov (United States)

    Rouse, Greg W; Goffredi, Shana K; Johnson, Shannon B; Vrijenhoek, Robert C

    2011-10-23

    Marine annelid worms of the genus Osedax exploit sunken vertebrate bones for food. To date, the named species occur on whale or other mammalian bones, and it is argued that Osedax is a whale-fall specialist. To assess whether extant Osedax species could obtain nutrition from non-mammalian resources, we deployed teleost bones and calcified shark cartilage at approximately 1000 m depth for five months. Although the evidence from shark cartilage was inconclusive, the teleost bones hosted three species of Osedax, each of which also lives off whalebones. This suggests that rather than being a whale-fall specialist, Osedax has exploited and continues to exploit a variety of food sources. The ability of Osedax to colonize and to grow on fishbone lends credibility to a hypothesis that it might have split from its siboglinid relatives to assume the bone-eating lifestyle during the Cretaceous, well before the origin of marine mammals. PMID:21490008

  8. The morphological diversity of Osedax worm borings (Annelidia: Siboglinidae)

    OpenAIRE

    Higgs, ND; Glover, AG; Dahlgren, TG; Smith, CR; Fujiwara, Y.; Pradillion, F; Johnson, SB; Vrijenhoek, RC; Little, CTS

    2014-01-01

    Marine worms in the genus Osedax, have specialized ‘root’ tissues used to bore into the bones of decomposing vertebrate skeletons and obtain nutrition. We investigated the borings of nine Osedax species, using micro computed tomography to quantitatively describe the morphology of the borings and provide three-dimensional reconstructions of the space occupied by Osedax root tissues inside the bone. Each Osedax species displayed a consistent boring morphology in any given bone, but these differ...

  9. Not whale-fall specialists, Osedax worms also consume fishbones

    OpenAIRE

    Rouse, Greg W.; Goffredi, Shana K.; Johnson, Shannon B.; Vrijenhoek, Robert C.

    2011-01-01

    Marine annelid worms of the genus Osedax exploit sunken vertebrate bones for food. To date, the named species occur on whale or other mammalian bones, and it is argued that Osedax is a whale-fall specialist. To assess whether extant Osedax species could obtain nutrition from non-mammalian resources, we deployed teleost bones and calcified shark cartilage at approximately 1000 m depth for five months. Although the evidence from shark cartilage was inconclusive, the teleost bones hosted three s...

  10. Osedax borings in fossil marine bird bones

    OpenAIRE

    Kiel, Steffen; Kahl, Wolf-Achim; Goedert, James

    2010-01-01

    The bone-eating marine annelid Osedax consumes mainly whale bones on the deep-sea floor, but recent colonization experiments with cow bones and molecular age estimates suggesting a possible Cretaceous origin of Osedax indicate that this worm might be able grow on a wider range of substrates. The suggested Cretaceous origin was thought to imply that Osedax could colonize marine reptile or fish bones, but there is currently no evidence that Osedax consumes bones other than those of mammals. We ...

  11. Osedax borings in fossil marine bird bones

    Science.gov (United States)

    Kiel, Steffen; Kahl, Wolf-Achim; Goedert, James L.

    2011-01-01

    The bone-eating marine annelid Osedax consumes mainly whale bones on the deep-sea floor, but recent colonization experiments with cow bones and molecular age estimates suggesting a possible Cretaceous origin of Osedax indicate that this worm might be able grow on a wider range of substrates. The suggested Cretaceous origin was thought to imply that Osedax could colonize marine reptile or fish bones, but there is currently no evidence that Osedax consumes bones other than those of mammals. We provide the first evidence that Osedax was, and most likely still is, able to consume non-mammalian bones, namely bird bones. Borings resembling those produced by living Osedax were found in bones of early Oligocene marine flightless diving birds (family Plotopteridae). The species that produced these boreholes had a branching filiform root that grew to a length of at least 3 mm, and lived in densities of up to 40 individuals per square centimeter. The inclusion of bird bones into the diet of Osedax has interesting implications for the recent suggestion of a Cretaceous origin of this worm because marine birds have existed continuously since the Cretaceous. Bird bones could have enabled this worm to survive times in the Earth's history when large marine vertebrates other than fish were rare, specifically after the disappearance of large marine reptiles at the end-Cretaceous mass extinction event and before the rise of whales in the Eocene.

  12. Worm

    CERN Document Server

    Bowden, Mark

    2012-01-01

    Worm is the gripping story of the 'Conficker' computer virus- which, since its introduction in November 2008, has infected millions of computers around the world - and the cyber security elites who have joined forces in a high-tech game of cops and robbers to find its creators and defeat them. This dramatic cybercrime story travels from the Ukraine to the United States (and all parts in between) to explore the next frontier in terrorism. It is the story of a dazzling battle of wits over the future of the Internet. In Worm, Mark Bowden delivers an unputdownable account of the ongoing and large

  13. Acquisition of dwarf male "harems" by recently settled females of Osedax roseus n. sp. (Siboglinidae; Annelida)

    DEFF Research Database (Denmark)

    Rouse, G W; Worsaae, K; Johnson, S. B.;

    2008-01-01

    with other Osedax spp., the females have dwarf males in their tube lumens. The males accrue over time until the sex ratio is markedly male-biased. This pattern of initial female settlement followed by gradual male accumulation is consistent with the hypothesis that male sex may be environmentally...

  14. The WORM site: worm.csirc.net

    International Nuclear Information System (INIS)

    The Write One, Run Many (WORM) site (worm.csirc.net) is the on-line home of the WORM language and is hosted by the Criticality Safety Information Resource Center (CSIRC) (www.csirc.net). The purpose of this web site is to create an on-line community for WORM users to gather, share, and archive WORM-related information. WORM is an embedded, functional, programming language designed to facilitate the creation of input decks for computer codes that take standard ASCII text files as input. A functional programming language is one that emphasizes the evaluation of expressions, rather than execution of commands. The simplest and perhaps most common example of a functional language is a spreadsheet such as Microsoft Excel. The spreadsheet user specifies expressions to be evaluated, while the spreadsheet itself determines the commands to execute, as well as the order of execution/evaluation. WORM functions in a similar fashion and, as a result, is very simple to use and easy to learn. WORM improves the efficiency of today's criticality safety analyst by allowing: (1) input decks for parameter studies to be created quickly and easily; (2) calculations and variables to be embedded into any input deck, thus allowing for meaningful parameter specifications; (3) problems to be specified using any combination of units; and (4) complex mathematically defined models to be created. WORM is completely written in Perl. Running on all variants of UNIX, Windows, MS-DOS, MacOS, and many other operating systems, Perl is one of the most portable programming languages available. As such, WORM works on practically any computer platform

  15. WormBase

    Data.gov (United States)

    U.S. Department of Health & Human Services — WormBase is an international consortium of biologists and computer scientists dedicated to providing the research community with accurate, current, accessible...

  16. Worm Infections in Children.

    Science.gov (United States)

    Weatherhead, Jill E; Hotez, Peter J

    2015-08-01

    • On the basis of research evidence, worm infections are important global child health conditions causing chronic disability that lasts from childhood into adulthood (Table 1). (2)(3) Evidence Quality: B • On the basis of research evidence, the major worm infections found in developing countries include ascariasis, trichuriasis, hookworm infection, and schistosomiasis; toxocariasis, enterobiasis, and cysticercosis are also found in poor regions of North America and Europe. (4)(9)(13) Evidence Quality: B • On the basis of expert consensus, children and adolescents are often vulnerable to acquiring large numbers of worms, ie, high-intensity infections (Fig 1)(21)(22)(23) Evidence Quality: D • On the basis of expert consensus and research evidence, moderate and heavy worm burdens cause increased morbidity because of growth and intellectual stunting in children and adolescents. Many of these effects may result from helminth-induced malnutrition. (21)(22)(23) Evidence Quality: C • On the basis of expert consensus and research evidence, worm infections are also commonly associated with eosinophilia. (48) (49) Evidence Quality: B • On the basis of research evidence as well as consensus, helminthes can cause inflammation in the lung (asthma), gastrointestinal tract (enteritis and colitis), liver (hepatitis and fibrosis), and urogenital tract. (7)(21)(22)(23)(27)(28)(40)(41)(43) Evidence Quality: B • On the basis of research evidence, microscopy techniques for diagnosis of worm infections in children often exhibit suboptimal sensitivities and specificities, necessitating new or improved diagnostic modalities such as polymerase chain reaction. (54)(55) Evidence Quality: A • On the basis of research evidence and expert consensus, mass drug administration (“preventive chemotherapy”) has becomea standard practice for ministries of health in low- and middle-income countries to control intestinal helminth infections and schistosomiasis. (67)(68) Evidence

  17. Living with Worms

    DEFF Research Database (Denmark)

    Bertoni, Filippo

    2016-01-01

    The thesis explores what living together can offer in rethinking political theory and in creating a space in which "politics" is not just a matter between people, but also with nature. These lessons about living together emerge from fieldwork around practices in which worms are central. Thus, the...

  18. Weird and wonderful worms

    OpenAIRE

    Wassink, J.

    2015-01-01

    In the WaterLab, biotechnologist Steef de Valk is carrying out experiments with tubifex worms. These threadlike creatures are capable of reducing by half the quantity of sewage sludge from water treatment. No-one really understands how this works.

  19. Intelligent System for Worm Detection

    Directory of Open Access Journals (Sweden)

    Tarek S. Sobh

    2009-01-01

    Full Text Available Worms are on the top of malware threats attacking computer system although of the evolution of worms detectiontechniques. Early detection of unknown worms is still a problem. This paper produce a method for detecting unknown wormsbased on local victim information. The proposed system uses Artificial Neural Network (ANN for classifying worm/ nonwormtraffic and predicting the percentage of infection in the infected network. This prediction can be used to support decisionmaking process for network administrator to respond quickly to worm propagation in an accurate procedure.

  20. Polymorphic Worms Collection in Cloud Computing

    OpenAIRE

    Ashraf A. Shahin

    2014-01-01

    In the past few years, computer worms are seen as one of significant challenges of cloud computing. Worms are rapidly changing and getting more sophisticated to evade detection. One major issue to defend against computer worms is collecting worms' payloads to generate their signature and study their behavior. To collect worms' payloads, we identified challenges for detecting and collecting worms' payloads and proposed high-interactive honeypot to collect payloads of zero-day polymorphic worms...

  1. Task 7c: Worm tank

    International Nuclear Information System (INIS)

    Worm tank has a unique shape. In the seismic design of a worm tank, it is desirable to clear the behavior of the worm tank under the seismic loading. We assumed that there are two phenomena in the seismic behavior of the worm tank same as the behavior of the cylindrical and rectangular tanks. One is a sloshing behavior of the water and another is the dynamic response of the worm tank. In this study, we investigate the dynamic characteristics of the worm tank during the strong earthquakes. We conducted the vibration tests to clarify the seismic behaviors of the worm tanks and obtained the valuable data to verify the analytical method. It was found that the natural frequency can be calculated using the eigenvalue formula of the cylindrical and rectangular tanks. Lower modes of the worm tank are identical with that of the rectangular tank. We can estimate the surface behavior and the impact mode using the data of the rectangular tank. (author)

  2. Drilling-worm unit

    Energy Technology Data Exchange (ETDEWEB)

    Levkovich, P.Ye.; Bratishcheva, L.L.; Lozovskiy, I.I.; Savich, N.S.

    1982-01-01

    The purpose of the invention is to improve efficiency of oriented well drilling. This goal is achieved because in the drilling worm unit which includes a worm sectional unit which is joined to the drilling crowns, whose main section is equipped with a bracket with device ahead of the drilling crowns for oriented well drilling, the latter is made in the form of two freely rotating wheels arranged on one side from the unit perpendicularly to its longitudinal axis and lying in one horizontal plane with the rotation axes of the drilling crowns, and the distance between the axis of rotation of the drilling crown and the rotation axis of the wheel adjoining it is less than the sum of their radii by a quantity which can be defined by a formula derived from the radius of the drilling crown and the thickness of the bracket. The design of the device for oriented well drilling in the form of two freely rotating wheels arranged on one side from the unit perpendicularly to its longitudinal axis to the drilling crowns lying in one horizontal plane with the rotation axes with distance between the rotation axis of the drilling crown and the rotation axis of the wheel adjoining it is less than the sum of their radii, by a quantity derived from the same parameters, and guarantees interaction of the device for oriented well drilling with the side walls of the previously drilled well. This makes it insensitive to rock collapses from the well roof and permits the static cutter to be eliminated, and consequently, elimination of the deflecting force and reduction in the feed force. All of this will permit improvement in the efficiency of well drilling.

  3. Characterizing Internet Worm Infection Structure

    CERN Document Server

    Wang, Qian; Chen, Chao

    2010-01-01

    Internet worm infection continues to be one of top security threats. Moreover, worm infection has been widely used by botnets to recruit new bots and construct P2P-based botnets. In this work, we attempt to characterize the network structure of Internet worm infection and shed light on the micro-level information of "who infects whom." Our work quantifies the infection ability of individual hosts and reveals the key characteristics of the underlying topologies formed by worm infection, i.e., the number of children and the generation of the Internet worm infection family tree. Specifically, we first analyze the infection tree of a wide class of worms, for which a new victim is compromised by each existing infected host with equal probability. We find that the number of children has asymptotically a geometric distribution with parameter 0.5. We also discover that the generation follows closely a Poisson distribution and the average path length of the worm infection family tree increases approximately logarithmi...

  4. Internet worm early detection and response mechanism

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In recent years, fast spreading worm has become one of the major threats to the security of the Internet and has an increasingly fierce tendency.In view of the insufficiency that based on Kalman filter worm detection algorithm is sensitive to interval, this article presents a new data collection plan and an improved worm early detection method which has some deferent intervals according to the epidemic worm propagation model, then proposes a worm response mechanism for slowing the wide and fast worm propagation effectively.Simulation results show that our methods are able to detect worms accurately and early.

  5. Encounter-based worms: Analysis and Defense

    CERN Document Server

    Tanachaiwiwat, Sapon

    2007-01-01

    Encounter-based network is a frequently-disconnected wireless ad-hoc network requiring immediate neighbors to store and forward aggregated data for information disseminations. Using traditional approaches such as gateways or firewalls for deterring worm propagation in encounter-based networks is inappropriate. We propose the worm interaction approach that relies upon automated beneficial worm generation aiming to alleviate problems of worm propagations in such networks. To understand the dynamic of worm interactions and its performance, we mathematically model worm interactions based on major worm interaction factors including worm interaction types, network characteristics, and node characteristics using ordinary differential equations and analyze their effects on our proposed metrics. We validate our proposed model using extensive synthetic and trace-driven simulations. We find that, all worm interaction factors significantly affect the pattern of worm propagations. For example, immunization linearly decrea...

  6. LUBRICATION BASIS THEORY OF WORM PAIR AND TEMPERATURE DISTRIBUTION ON WORM GEAR SURFACE

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    The lubrication basis theory of worm pair is given. The lubrication state of worm gear is analyzed. It is found that the temperature distribution on the tooth surface of worm gear is closely related with the lubrication state and that the temperature on the tooth surface of worm gear is consistent with the characteristic term of mesh and motion of worm pair.

  7. Defense and detection strategies against Internet worms

    CERN Document Server

    Nazario, José

    2004-01-01

    This is the first book focused exclusively on Internet worms, offering you solid worm detection and mitigation strategies for your work in the field. This ground-breaking volume enables you to put rising worm trends into perspective with practical information in detection and defense techniques utilizing data from live networks, real IP addresses, and commercial tools. The book helps you understand the classifications and groupings of worms, and offers a deeper understanding of how they threaten network and system security.

  8. New Multi-step Worm Attack Model

    CERN Document Server

    Robiah, Y; Shahrin, S; Faizal, M A; Zaki, M Mohd; Marliza, R

    2010-01-01

    The traditional worms such as Blaster, Code Red, Slammer and Sasser, are still infecting vulnerable machines on the internet. They will remain as significant threats due to their fast spreading nature on the internet. Various traditional worms attack pattern has been analyzed from various logs at different OSI layers such as victim logs, attacker logs and IDS alert log. These worms attack pattern can be abstracted to form worms' attack model which describes the process of worms' infection. For the purpose of this paper, only Blaster variants were used during the experiment. This paper proposes a multi-step worm attack model which can be extended into research areas in alert correlation and computer forensic investigation.

  9. Darknet-Based Inference of Internet Worm Temporal Characteristics

    OpenAIRE

    Wang, Qian; Chen, Zesheng; Chen, Chao

    2010-01-01

    Internet worm attacks pose a significant threat to network security and management. In this work, we coin the term Internet worm tomography as inferring the characteristics of Internet worms from the observations of Darknet or network telescopes that monitor a routable but unused IP address space. Under the framework of Internet worm tomography, we attempt to infer Internet worm temporal behaviors, i.e., the host infection time and the worm infection sequence, and thus pinpoint patient zero o...

  10. Tackling the Threats of Internet Worms

    OpenAIRE

    Al-Sakib Khan Pathan

    2012-01-01

    Computer Worm is a kind of malicious program that self-replicates automatically within a computer network. Again, Internet is defined as a network of networks. This is the reason why computer worms do not reside only within one computer or a single network but rather get spread all over the Internet whenever it is possible during computer-to-computer communications. The reality of today’s Internet is that the worms pose a major threat to the Internet infrastructure security. This is also unde...

  11. Worm Epidemics in Wireless Adhoc Networks

    CERN Document Server

    Nekovee, Maziar

    2007-01-01

    A dramatic increase in the number of computing devices with wireless communication capability has resulted in the emergence of a new class of computer worms which specifically target such devices. The most striking feature of these worms is that they do not require Internet connectivity for their propagation but can spread directly from device to device using a short-range radio communication technology, such as WiFi or Bluetooth. In this paper, we develop a new model for epidemic spreading of these worms and investigate their spreading in wireless ad hoc networks via extensive Monte Carlo simulations. Our studies show that the threshold behaviour and dynamics of worm epidemics in these networks are greatly affected by a combination of spatial and temporal correlations which characterize these networks, and are significantly different from the previously studied epidemics in the Internet.

  12. Worm epidemics in wireless ad hoc networks

    Science.gov (United States)

    Nekovee, Maziar

    2007-06-01

    A dramatic increase in the number of computing devices with wireless communication capability has resulted in the emergence of a new class of computer worms which specifically target such devices. The most striking feature of these worms is that they do not require Internet connectivity for their propagation but can spread directly from device to device using a short-range radio communication technology, such as WiFi or Bluetooth. In this paper, we develop a new model for epidemic spreading of these worms and investigate their spreading in wireless ad hoc networks via extensive Monte Carlo simulations. Our studies show that the threshold behaviour and dynamics of worm epidemics in these networks are greatly affected by a combination of spatial and temporal correlations which characterize these networks, and are significantly different from the previously studied epidemics in the Internet.

  13. Detecting Internet Worms Using Data Mining Techniques

    Directory of Open Access Journals (Sweden)

    Muazzam Siddiqui

    2008-12-01

    Full Text Available Internet worms pose a serious threat to computer security. Traditional approaches using signatures to detect worms pose little danger to the zero day attacks. The focus of malware research is shifting from using signature patterns to identifying the malicious behavior displayed by the malwares. This paper presents a novel idea of extracting variable length instruction sequences that can identify worms from clean programs using data mining techniques. The analysis is facilitated by the program control flow information contained in the instruction sequences. Based upon general statistics gathered from these instruction sequences we formulated the problem as a binary classification problem and built tree based classifiers including decision tree, bagging and random forest. Our approach showed 95.6% detection rate on novel worms whose data was not used in the model building process.

  14. Worm epidemics in wireless ad hoc networks

    International Nuclear Information System (INIS)

    A dramatic increase in the number of computing devices with wireless communication capability has resulted in the emergence of a new class of computer worms which specifically target such devices. The most striking feature of these worms is that they do not require Internet connectivity for their propagation but can spread directly from device to device using a short-range radio communication technology, such as WiFi or Bluetooth. In this paper, we develop a new model for epidemic spreading of these worms and investigate their spreading in wireless ad hoc networks via extensive Monte Carlo simulations. Our studies show that the threshold behaviour and dynamics of worm epidemics in these networks are greatly affected by a combination of spatial and temporal correlations which characterize these networks, and are significantly different from the previously studied epidemics in the Internet

  15. Scenario Based Worm Trace Pattern Identification Technique

    CERN Document Server

    Rahayu, S Siti; Shahrin, S; Zaki, Mohd M; Irda, R; Faizal, M A

    2010-01-01

    The number of malware variants is growing tremendously and the study of malware attacks on the Internet is still a demanding research domain. In this research, various logs from different OSI layer are explore to identify the traces leave on the attacker and victim logs, and the attack worm trace pattern are establish in order to reveal true attacker or victim. For the purpose of this paper, it will only concentrate on cybercrime that caused by malware network intrusion and used the traditional worm namely blaster worm variants. This research creates the concept of trace pattern by fusing the attackers and victims perspective. Therefore, the objective of this paper is to propose on attackers, victims and multistep, attacker or victim, trace patterns by combining both perspectives. These three proposed worm trace patterns can be extended into research areas in alert correlation and computer forensic investigation.

  16. Worming our way closer to the clinic

    OpenAIRE

    Hepworth, Matthew R.; Hartmann, Susanne

    2012-01-01

    In a recent issue of “The International Journal for Parasitology: Drugs and Drug Resistance” Prof. David Pritchard from the University of Nottingham offers his intriguing opinion on the current status of “worm therapy” and outlines future research priorities aimed at bringing this research area closer to the clinic. In this response article we discuss various aspects of the current state of the research field and offer some alternative viewpoints regarding the future of “worm therapy”....

  17. Polyamide worm gear: manufacturing and performance

    OpenAIRE

    Alexandre Luís Gasparin; Leandro Luís Corso; Eduardo Kirinus Tentardini; Regina Célia Reis Nunes; Maria Madalena Camargo Forte; Ricardo Vinicius Bof de Oliveira

    2012-01-01

    The focus of this paper is to establish a characterisation method for seven polyamide (PA) grades to determine the major material to manufacture an automotive worm gear. The composite properties were measured according to the worm gear loadings: tensile strength, Young's modulus, abrasion and impact resistance. They were also correlated to the PA moisture absorption and its glass fibre (GF) reinforcement. The data from mechanical tests were applied in the finite element analysis (FEA) using t...

  18. Research of internet worm warning system based on system identification

    Institute of Scientific and Technical Information of China (English)

    Tao ZHOU; Guanzhong DAI; Huimin YE

    2006-01-01

    The frequent explosion of Internet worms has been one of the most serious problems in cyberspace security.In this paper, by analyzing the worm's propagation model, we propose a new worm warning system based on the method of system identification, and use recursive least squares algorithm to estimate the worm's infection rate. The simulation result shows the method we adopted is an efficient way to conduct Internet worm warning.

  19. Aquatic worms eat sludge: Mass balances and processing of worm faeces

    International Nuclear Information System (INIS)

    Reduction of the amount of waste sludge from waste water treatment plants (WWTPs) can be achieved with the aquatic worm Lumbriculus variegatus in a new reactor concept. In addition to reducing the amount of waste sludge, further processing of produced worm faeces and released nutrients should also be considered. This study gives the mass balances for sludge consumed by L. variegatus, showing the fate of the consumed organic material, nutrients and heavy metals associated with the sludge. A distinction is made between conversion into worm biomass, release as dissolved metabolites and what remains in the worm faeces. The results showed that 39% of the nitrogen and 12% of the phosphorus in the sludge digested by the worms are used in the formation of new worm biomass, which has potential for reuse. Experiments showed that settling of the worm faeces leads to a factor 2.5 higher solids concentration, compared to settling of waste sludge. This could lead to a 67% reduction of the volumetric load on thickening equipment. The worm reactor is expected to be most interesting for smaller WWTPs where a decrease on the volumetric load on sludge handling operations will have most impact.

  20. Disulfide-Functionalized Diblock Copolymer Worm Gels.

    Science.gov (United States)

    Warren, Nicholas J; Rosselgong, Julien; Madsen, Jeppe; Armes, Steven P

    2015-08-10

    Two strategies for introducing disulfide groups at the outer surface of RAFT-synthesized poly(glycerol monomethacrylate)-poly(2-hydroxypropyl methacrylate) (PGMA-PHPMA, or Gx-Hy for brevity) diblock copolymer worms are investigated. The first approach involved statistical copolymerization of GMA with a small amount of disulfide dimethacrylate (DSDMA, or D) comonomer to afford a G54-D0.50 macromolecular chain transfer agent (macro-CTA); this synthesis was conducted in relatively dilute solution in order to ensure mainly intramolecular cyclization and hence the formation of linear chains. Alternatively, a new disulfide-based bifunctional RAFT agent (DSDB) was used to prepare a G45-S-S-G45 (or (G45-S)2) macro-CTA. A binary mixture of a non-functionalized G55 macro-CTA was utilized with each of these two disulfide-based macro-CTAs in turn for the RAFT aqueous dispersion polymerization of 2-hydroxypropyl methacrylate (HPMA). By targeting a PHPMA DP of 130 and systematically varying the molar ratio of the two macro-CTAs, a series of disulfide-functionalized diblock copolymer worm gels were obtained. For both formulations, oscillatory rheology studies confirmed that higher disulfide contents led to stronger gels, presumably as a result of inter-worm covalent bond formation via disulfide/thiol exchange. Using the DSDB-based macro-CTA led to the strongest worm gels, and this formulation also proved to be more effective in suppressing the thermosensitive behavior that is observed for the nondisulfide-functionalized control worm gel. However, macroscopic precipitation occurred when the proportion of DSDB-based macro-CTA was increased to 50 mol %, whereas the DSDMA-based macro-CTA could be utilized at up to 80 mol %. Finally, the worm gel modulus could be reduced to that of a nondisulfide-containing worm gel by reductive cleavage of the inter-worm disulfide bonds using excess tris(2-carboxyethyl)phosphine (TCEP) to yield thiol groups. These new biomimetic worm gels are

  1. Polyamide worm gear: manufacturing and performance

    Directory of Open Access Journals (Sweden)

    Alexandre Luís Gasparin

    2012-06-01

    Full Text Available The focus of this paper is to establish a characterisation method for seven polyamide (PA grades to determine the major material to manufacture an automotive worm gear. The composite properties were measured according to the worm gear loadings: tensile strength, Young's modulus, abrasion and impact resistance. They were also correlated to the PA moisture absorption and its glass fibre (GF reinforcement. The data from mechanical tests were applied in the finite element analysis (FEA using the von Mises stress criterion. Before the rig tests of the PA worm gears, the injection process was evaluated, through the capillary rheometry. A higher difficulty to process PA 6/6 30% GF was found, due to its lower apparent viscosity. In the end, the influence of moisture absorption was as decisive to the gear's material selection as the GF to the pinion. Thus, the PAs with the best performance were: PA 6 with 30% GF (gear and with PA 60% GF (pinion.

  2. Filarial worms reduce Plasmodium infectivity in mosquitoes.

    Directory of Open Access Journals (Sweden)

    Matthew T Aliota

    Full Text Available BACKGROUND: Co-occurrence of malaria and filarial worm parasites has been reported, but little is known about the interaction between filarial worm and malaria parasites with the same Anopheles vector. Herein, we present data evaluating the interaction between Wuchereria bancrofti and Anopheles punctulatus in Papua New Guinea (PNG. Our field studies in PNG demonstrated that An. punctulatus utilizes the melanization immune response as a natural mechanism of filarial worm resistance against invading W. bancrofti microfilariae. We then conducted laboratory studies utilizing the mosquitoes Armigeres subalbatus and Aedes aegypti and the parasites Brugia malayi, Brugia pahangi, Dirofilaria immitis, and Plasmodium gallinaceum to evaluate the hypothesis that immune activation and/or development by filarial worms negatively impact Plasmodium development in co-infected mosquitoes. Ar. subalbatus used in this study are natural vectors of P. gallinaceum and B. pahangi and they are naturally refractory to B. malayi (melanization-based refractoriness. METHODOLOGY/PRINCIPAL FINDINGS: Mosquitoes were dissected and Plasmodium development was analyzed six days after blood feeding on either P. gallinaceum alone or after taking a bloodmeal containing both P. gallinaceum and B. malayi or a bloodmeal containing both P. gallinaceum and B. pahangi. There was a significant reduction in the prevalence and mean intensity of Plasmodium infections in two species of mosquito that had dual infections as compared to those mosquitoes that were infected with Plasmodium alone, and was independent of whether the mosquito had a melanization immune response to the filarial worm or not. However, there was no reduction in Plasmodium development when filarial worms were present in the bloodmeal (D. immitis but midgut penetration was absent, suggesting that factors associated with penetration of the midgut by filarial worms likely are responsible for the observed reduction in malaria

  3. Parasitic worms in organic laying hens

    OpenAIRE

    Iepema, msc. Goaitske; Wagenaar, msc Jan-Paul; Bestman, msc. Monique

    2006-01-01

    Laying hens in alternative systems run a higher risk for infections with parasitic worms than when kept in a cage system. Organic farmers generally prefer not to use chemical medicines, but at the same time they are afraid to run health or production risks. Our aim was to get an overview of the current situation concerning the prevalence of parasitic worms in organic laying hens and whether it makes a difference when farmers use anthelmintics. We monitored 16 flocks of organic laying hens on ...

  4. Darknet-Based Inference of Internet Worm Temporal Characteristics

    CERN Document Server

    Wang, Qian; Chen, Chao

    2010-01-01

    Internet worm attacks pose a significant threat to network security and management. In this work, we coin the term Internet worm tomography as inferring the characteristics of Internet worms from the observations of Darknet or network telescopes that monitor a routable but unused IP address space. Under the framework of Internet worm tomography, we attempt to infer Internet worm temporal behaviors, i.e., the host infection time and the worm infection sequence, and thus pinpoint patient zero or initially infected hosts. Specifically, we introduce statistical estimation techniques and propose method of moments, maximum likelihood, and linear regression estimators. We show analytically and empirically that our proposed estimators can better infer worm temporal characteristics than a naive estimator that has been used in the previous work. We also demonstrate that our estimators can be applied to worms using different scanning strategies such as random scanning and localized scanning.

  5. Facing Two Rapidly Spreading Internet Worms

    CERN Multimedia

    IT Department

    2009-01-01

    The Internet is currently facing a growing number of computer infections due to two rapidly spreading worms. The "Conficker" and "Downadup" worms have infected an estimated 1.1 million PCs in a 24-hour period, bringing the total number of infected computers to 3.5 million [1]. Via a single USB stick, these worms were also responsible for the infection of about 40 laptops at the last EGEE conference in Istanbul. In order to reduce the impact of these worms on CERN Windows computers, the Computer Security Team has suggested several preventive measures described here. Disabling the Windows AutoRun and AutoPlay Features The Computer Security Team and the IT/IS group have decided to disable the "AutoRun" and "AutoPlay" functionality on all centrally-managed Windows computers at CERN. When inserting CDs, DVDs or USB sticks into a PC, "AutoRun" and "AutoPlay" are responsible for automatically playing music or films stored on these media, or ...

  6. Streptomycetes - food source for enchytraeid worms (Enchytraeidae)

    Czech Academy of Sciences Publication Activity Database

    Krištůfek, Václav; Schrempf, H.

    Melbourne: Melbourne Convention Centre, 2003. s. 72. [International Symposium on the Biology of Actinomycetes /13./. 01.12.2003-05.12.2003, Melbourne] Institutional research plan: CEZ:AV0Z6066911 Keywords : Streptomycetes * food * enchytraeid worms Subject RIV: EH - Ecology, Behaviour

  7. An Impulse Dynamic Model for Computer Worms

    OpenAIRE

    Yingjiang Wu; Yun Zhao; Chunming Zhang

    2013-01-01

    A worm spread model concerning impulsive control strategy is proposed and analyzed. We prove that there exists a globally attractive virus-free periodic solution when the vaccination rate is larger than ${\\theta }_{1}$ . Moreover, we show that the system is uniformly persistent if the vaccination rate is less than ${\\theta }_{1}$ . Some numerical simulations are also given to illustrate our main results.

  8. Method of drill-worm coal extraction

    Energy Technology Data Exchange (ETDEWEB)

    Levkovich, P.Ye.; Bratishcheva, L.L.; Savich, N.S.

    1982-09-01

    The purpose of the invention is to increase extraction productivity. This goal is achieved because according to the method of drill-worm coal extraction which includes drilling from one preparatory shaft to the second of wells by paired worm shaft on a guide which is pulled into the drilled well during reverse course of the shaft, and reinforcement of the drilled well, the drilled well is reinforced by a wedge timbering which bulges out during drilling of the next well. According to the proposed method, coal is extracted by drilling wells from the preparatory shaft 1 (a haulage gallery is shown in the example). Drilling of the wells is done with the help of a sectional worm shaft equipped with a drilling crown and guide device, equipped with a cantilever used to attach the guide device to the main section of the worm shaft. The guide device also includes two horizontally installed, freely rotating cylinders located in front of the drilling crowns in the previously drilled well and the guide ski. During drilling of the well in the second preparatory shaft (a ventilation gallery is indicated in the example) on the guide platform sets of wedge timbering are installed connected with the help of flexible ties, for example chain segments. The wedge timbering (including the main set) consists of wedge elements made of inexpensive material, for example slag-concrete.

  9. Sampling of general correlators in worm-algorithm based simulations

    Science.gov (United States)

    Rindlisbacher, Tobias; Åkerlund, Oscar; de Forcrand, Philippe

    2016-08-01

    Using the complex ϕ4-model as a prototype for a system which is simulated by a worm algorithm, we show that not only the charged correlator , but also more general correlators such as or , as well as condensates like , can be measured at every step of the Monte Carlo evolution of the worm instead of on closed-worm configurations only. The method generalizes straightforwardly to other systems simulated by worms, such as spin or sigma models.

  10. Sampling of General Correlators in Worm Algorithm-based Simulations

    CERN Document Server

    Rindlisbacher, Tobias; de Forcrand, Philippe

    2016-01-01

    Using the complex $\\phi^4$-model as a prototype for a system which is simulated by a (bosonic) worm algorithm, we show that not only the charged correlator $$, but also more general correlators such as $$ or $$ as well as condensates like $$ can be measured at every step of the Monte Carlo evolution of the worm instead of on closed-worm configurations only. The method generalizes straightforwardly to other systems simulated by (bosonic) worms, such as spin or sigma models.

  11. Defending Polymorphic Worms in Computer Network using Honeypot

    Directory of Open Access Journals (Sweden)

    R. T. Goswamia

    2012-10-01

    Full Text Available Polymorphic worms are a major threat to internet infrastructure security. In this mechanism we are using gate-translator, double honeypot, sticky honeypot, internal translator and antivirus of Cloud AV,which attracts polymorphic worms. We are proposing an algorithm to detect and remove polymorphic worms and innocuous traffic related packets.

  12. Defending Polymorphic Worms in Computer Network using Honeypot

    OpenAIRE

    R. T. Goswamia

    2012-01-01

    Polymorphic worms are a major threat to internet infrastructure security. In this mechanism we are using gate-translator, double honeypot, sticky honeypot, internal translator and antivirus of Cloud AV,which attracts polymorphic worms. We are proposing an algorithm to detect and remove polymorphic worms and innocuous traffic related packets.

  13. Worms Propagation Modeling and Analysis in Big Data Environment

    OpenAIRE

    Song He; Can Zhang; Wei Guo; Li-Dong Zhai

    2015-01-01

    The integration of the Internet and Mobile networks results in huge amount of data, as well as security threat. With the fragile capacity of security protection, worms can propagate in the integration network and undermine the stability and integrity of data. The propagation of worm is a great security risk to massive amounts of data in the integration network. We propose a kind of worm propagating in big data environment named BD-Worm. BD-Worm consumes computing resources and gets privacy in...

  14. Critical loop gases and the worm algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Janke, Wolfhard [Institut fuer Theoretische Physik, Universitaet Leipzig, Postfach 100 920, D-04009 Leipzig (Germany); Neuhaus, Thomas [Juelich Supercomputing Centre, Forschungszentrum Juelich, D-52425 Juelich (Germany); Schakel, Adriaan M.J., E-mail: schakel@itp.uni-leipzig.d [Institut fuer Theoretische Physik, Universitaet Leipzig, Postfach 100 920, D-04009 Leipzig (Germany)

    2010-04-21

    The loop gas approach to lattice field theory provides an alternative, geometrical description in terms of fluctuating loops. Statistical ensembles of random loops can be efficiently generated by Monte Carlo simulations using the worm update algorithm. In this paper, concepts from percolation theory and the theory of self-avoiding random walks are used to describe estimators of physical observables that utilize the nature of the worm algorithm. The fractal structure of the random loops as well as their scaling properties are studied. To support this approach, the O(1) loop model, or high-temperature series expansion of the Ising model, is simulated on a honeycomb lattice, with its known exact results providing valuable benchmarks.

  15. Worms,Your Unlikely Allies etc

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Back in the Stone Age,humans had to put up with all sorts of creepy crawlies.Parasites - organisms that live on or in another organism - lingered inside our bodies,living off of our blood.Because internal parasites go mostly unnoticed,they were able to keep living with humans.People can survive a long time with tiny parasitic worms in their intestines.

  16. TORQUE MEASUREMENT IN WORM AGLOMERATION MACHINE

    Directory of Open Access Journals (Sweden)

    Marian DUDZIAK

    2014-03-01

    Full Text Available The paper presents the operating characteristics of the worm agglomeration machine. The paper indicates the need for continuous monitoring of the value of the torque due to the efficiency of the machine. An original structure of torque meter which is built in the standard drive system of briquetting machine was presented. A number of benefits arising from the application of the proposed solution were presented. Exemplary measurement results obtained by means of this torque meter were presented.

  17. TORQUE MEASUREMENT IN WORM AGLOMERATION MACHINE

    OpenAIRE

    Marian DUDZIAK; Ireneusz MALUJDA; Krzysztof TALAŚKA

    2014-01-01

    The paper presents the operating characteristics of the worm agglomeration machine. The paper indicates the need for continuous monitoring of the value of the torque due to the efficiency of the machine. An original structure of torque meter which is built in the standard drive system of briquetting machine was presented. A number of benefits arising from the application of the proposed solution were presented. Exemplary measurement results obtained by means of this torque meter were presented.

  18. Parametric Analysis of the End Face Engagement Worm Gear

    Institute of Scientific and Technical Information of China (English)

    DENG Xingqiao; WANG Jueling; WANG Jinge; CHEN Shouan; YANG Jie

    2015-01-01

    A novel specific type of worm drive, so-called end face engagement worm gear(EFEWD), is originally presented to minimize or overcome the gear backlash. Different factors, including the three different types, contact curves, tooth profile, lubrication angle and the induced normal curvature are taken into account to investigate the meshing characteristics and create the profile of a novel specific type of worm drive through mathematical models and theoretical analysis. The tooth of the worm wheel is very specific with the sine-shaped tooth which is located at the alveolus of the worm and the tooth profile of a worm is generated by the meshing movement of the worm wheel with the sine-shaped tooth, but just the end face of the worm(with three different typical meshing types) is adapted to meshing, and therefore an extraordinary manufacturing methods is used to generate the profile of the end face engagement worm. The research results indicates that the bearing contacts of the generated conjugate hourglass worm gear set are in line contacts, with certain advantages of no-backlash, high precision and high operating efficiency over other gears and gear systems besides the end face engagement worm gear drive may improve bearing contact, reduce the level of transmission errors and lessen the sensitivity to errors of alignment. Also, the end face engagement worm can be easily made with superior meshing and lubrication performance compared with the conventional techniques. In particular, the meshing and lubrication performance of the end face engagement worm gear by using the end face to meshing can be increased over 10% and 7%, respectively. This investigate is expect to provide a new insight on the design of the future no-backlash worm drive for industry.

  19. Parametric analysis of the end face engagement worm gear

    Science.gov (United States)

    Deng, Xingqiao; Wang, Jueling; Wang, Jinge; Chen, Shouan; Yang, Jie

    2015-11-01

    A novel specific type of worm drive, so-called end face engagement worm gear(EFEWD), is originally presented to minimize or overcome the gear backlash. Different factors, including the three different types, contact curves, tooth profile, lubrication angle and the induced normal curvature are taken into account to investigate the meshing characteristics and create the profile of a novel specific type of worm drive through mathematical models and theoretical analysis. The tooth of the worm wheel is very specific with the sine-shaped tooth which is located at the alveolus of the worm and the tooth profile of a worm is generated by the meshing movement of the worm wheel with the sine-shaped tooth, but just the end face of the worm(with three different typical meshing types) is adapted to meshing, and therefore an extraordinary manufacturing methods is used to generate the profile of the end face engagement worm. The research results indicates that the bearing contacts of the generated conjugate hourglass worm gear set are in line contacts, with certain advantages of no-backlash, high precision and high operating efficiency over other gears and gear systems besides the end face engagement worm gear drive may improve bearing contact, reduce the level of transmission errors and lessen the sensitivity to errors of alignment. Also, the end face engagement worm can be easily made with superior meshing and lubrication performance compared with the conventional techniques. In particular, the meshing and lubrication performance of the end face engagement worm gear by using the end face to meshing can be increased over 10% and 7%, respectively. This investigate is expect to provide a new insight on the design of the future no-backlash worm drive for industry.

  20. Running worms: C. elegans self-sorting by electrotaxis.

    Directory of Open Access Journals (Sweden)

    Xavier Manière

    Full Text Available The nematode C. elegans displays complex dynamical behaviors that are commonly used to identify relevant phenotypes. Although its maintenance is straightforward, sorting large populations of worms when looking for a behavioral phenotype is difficult, time consuming and hardly quantitative when done manually. Interestingly, when submitted to a moderate electric field, worms move steadily along straight trajectories. Here, we report an inexpensive method to measure worms crawling velocities and sort them within a few minutes by taking advantage of their electrotactic skills. This method allows to quantitatively measure the effect of mutations and aging on worm's crawling velocity. We also show that worms with different locomotory phenotypes can be spatially sorted, fast worms traveling away from slow ones. Group of nematodes with comparable locomotory fitness could then be isolated for further analysis. C. elegans is a growing model for neurodegenerative diseases and using electrotaxis for self-sorting can improve the high-throughput search of therapeutic bio-molecules.

  1. Preparation of Pickering Double Emulsions Using Block Copolymer Worms

    OpenAIRE

    Thompson, Kate L.; Mable, Charlotte J.; Lane, Jacob A.; Derry, Mathew J.; Fielding, Lee A.; Armes, Steven P.

    2015-01-01

    The rational formulation of Pickering double emulsions is described using a judicious combination of hydrophilic and hydrophobic block copolymer worms as highly anisotropic emulsifiers. More specifically, RAFT dispersion polymerization was utilized to prepare poly(lauryl methacrylate)–poly(benzyl methacrylate) worms at 20% w/w solids in n-dodecane and poly(glycerol monomethacrylate)–poly(2-hydroxypropyl methacrylate)–poly(benzyl methacrylate) worms at 13% w/w solids in water by polymerization...

  2. Predicting the Presence of Internet Worms using Novelty Detection

    OpenAIRE

    Marais, E.; Marwala, T.

    2007-01-01

    Internet worms cause billions of dollars in damage yearly, affecting millions of users worldwide. For countermeasures to be deployed timeously, it is necessary to use an automated system to detect the spread of a worm. This paper discusses a method of determining the presence of a worm, based on routing information currently available from Internet routers. An autoencoder, which is a specialized type of neural network, was used to detect anomalies in normal routing behavior. The autoencoder w...

  3. Design a Security Network System against Internet Worms

    OpenAIRE

    Rana Dhia'a Abdu-Aljabar

    2012-01-01

    Active worms have posed a major security threat to the Internet, and many research efforts have focused on them. This paper is interested in internet worm that spreads via TCP, which accounts for the majority of internet traffic. It presents an approach that use a hybrid solution between two detection algorithms: behavior base detection and signature base detection to have the features of each of them. The aim of this study is to have a good solution of detecting worm and stealthy worm with t...

  4. WormBook: the online review of Caenorhabditis elegans biology

    OpenAIRE

    Girard, Lisa R.; Fiedler, Tristan J.; Harris, Todd W.; Carvalho, Felicia; Antoshechkin, Igor; Han, Michael; Sternberg, Paul W.; Stein, Lincoln D; Chalfie, Martin

    2007-01-01

    WormBook (www.wormbook.org) is an open-access, online collection of original, peer-reviewed chapters on the biology of Caenorhabditis elegans and related nematodes. Since WormBook was launched in June 2005 with 12 chapters, it has grown to over 100 chapters, covering nearly every aspect of C.elegans research, from Cell Biology and Neurobiology to Evolution and Ecology. WormBook also serves as the text companion to WormBase, the C.elegans model organism database. Objects such as genes, protein...

  5. Predicting the Presence of Internet Worms using Novelty Detection

    CERN Document Server

    Marais, E

    2007-01-01

    Internet worms cause billions of dollars in damage yearly, affecting millions of users worldwide. For countermeasures to be deployed timeously, it is necessary to use an automated system to detect the spread of a worm. This paper discusses a method of determining the presence of a worm, based on routing information currently available from Internet routers. An autoencoder, which is a specialized type of neural network, was used to detect anomalies in normal routing behavior. The autoencoder was trained using information from a single router, and was able to detect both global instability caused by worms as well as localized routing instability.

  6. Dual-worm screw compressors; Compresseurs bi-vis

    Energy Technology Data Exchange (ETDEWEB)

    Baleydier, J.P. [Bitzer France, 69 - Lyon (France)

    1997-12-31

    Low power worm-screw moto-compressors are used in any king of refrigerating machineries and more and more in air conditioning systems. This paper presents the principle of dual-screw moto-compressors: worm-screw technology, role of oil (lubrication, tightness, cooling), compression, internal pressure, power reduction, lubrication, economizer, operation, model selection and accessories. (J.S.)

  7. Defending Polymorphic Worms in Computer network using Honeynet

    Directory of Open Access Journals (Sweden)

    Upendra Kumar

    2012-04-01

    Full Text Available We propose a defense mechanism in computer network using gate-translator, double honeynet, sticky honeypot and antivirus engine of CloudAV, which attracts polymorphic worms. An algorithm is proposed to detect and remove the polymorphic worms and innocuous traffic related packets. Future antivirus is implemented on logically detached unused system.

  8. Worm plot to diagnose fit in quantile regression

    NARCIS (Netherlands)

    Buuren, S. van

    2007-01-01

    The worm plot is a series of detrended Q-Q plots, split by covariate levels. The worm plot is a diagnostic tool for visualizing how well a statistical model fits the data, for finding locations at which the fit can be improved, and for comparing the fit of different models. This paper shows how the

  9. Research and Development of P2P Worms

    Institute of Scientific and Technical Information of China (English)

    Li You; Zhi-Guang Qin

    2011-01-01

    With the development and the application of many popular peer-to-peer (P2P) systems such as eMule and BitTorrent,worms probably employ the features of these P2P networks to put them at risk.Some features,such as the local routing table and the application routing mechanism,are helpful to quickly distribute the P2P worms into the networks.This paper aims to give a comprehensive survey of P2P worms.The definition and the classification of P2P worms are discussed firstly.Then,the research and development of P2P worms, including experimental analysis,propagation modeling,and defensive approaches,are addressed and analyzed in detail.

  10. Can aquatic worms enhance methane production from waste activated sludge?

    Science.gov (United States)

    Serrano, Antonio; Hendrickx, Tim L G; Elissen, Hellen H J; Laarhoven, Bob; Buisman, Cees J N; Temmink, Hardy

    2016-07-01

    Although literature suggests that aquatic worms can help to enhance the methane production from excess activated sludge, clear evidence for this is missing. Therefore, anaerobic digestion tests were performed at 20 and at 30°C with sludge from a high-loaded membrane bioreactor, the aquatic worm Lumbriculus variegatus, feces from these worms and with mixtures of these substrates. A significant synergistic effect of the worms or their feces on methane production from the high-loaded sludge or on its digestion rate was not observed. However, a positive effect on low-loaded activated sludge, which generally has a lower anaerobic biodegradability, cannot be excluded. The results furthermore showed that the high-loaded sludge provides an excellent feed for L. variegatus, which is promising for concepts where worm biomass is considered a resource for technical grade products such as coatings and glues. PMID:26998797

  11. How the velvet worm squirts slime

    CERN Document Server

    Concha, Andrés; Morera-Brenes, Bernal; Costa, Cristiano Sampaio; Mahadevan, L; Monge-Nájera, Julián

    2014-01-01

    The rapid squirt of a proteinaceous slime jet endows the ancient velvet worms (Onychophora) with a unique mechanism for defense from predators and for capturing prey by entangling them in a disordered web that immobilizes their target. However, to date neither qualitative nor quantitative descriptions have been provided for this unique adaptation. Here we investigate the fast oscillatory motion of the oral papillae and the exiting liquid jet that oscillates with frequencies $f\\sim 30-60$ Hz. Using anatomical images, high speed videography, theoretical analysis and a physical simulacrum we show that this fast oscillatory motion is the result of an elastohydrodynamic instability driven by the interplay between the elasticity of oral papillae and the fast unsteady flow during squirting. Our results demonstrate how passive strategies can be cleverly harnessed by organisms, while suggesting future oscillating micro-fluidic devices as well as novel ways for micro and nano fiber production using bioinspired strategi...

  12. The theory and practice of worm gear drives

    CERN Document Server

    Dudás, Ilés

    2005-01-01

    Worm gears are special gears that resemble screws, and can be used to drive other gears. Worm gears, enable two non-touching shafts in a machine to mesh (join) together. This publication, unique in that it combines both theoretical and practical design aspects, including the latest results of research and development, provides detailed treatment of the theory and production of worm drives, as well as the overarching subject of production geometry of helicoidal surfaces.Included are mathematical models for a number of practical applications; a description of dressing equipment r

  13. WormBase: a comprehensive resource for nematode research

    OpenAIRE

    Todd W Harris; Antoshechkin, Igor; Bieri, Tamberlyn; Blasiar, Darin; Chan, Juancarlos; Chen, Wen J.; De La Cruz, Norie; Davis, Paul; Duesbury, Margaret; Fang, Ruihua; Fernandes, Jolene; Han, Michael; Kishore, Ranjana; Lee, Raymond; Müller, Hans-Michael

    2010-01-01

    WormBase (http://www.wormbase.org) is a central data repository for nematode biology. Initially created as a service to the Caenorhabditis elegans research field, WormBase has evolved into a powerful research tool in its own right. In the past 2 years, we expanded WormBase to include the complete genomic sequence, gene predictions and orthology assignments from a range of related nematodes. This comparative data enrich the C. elegans data with improved gene predictions and a better understand...

  14. A worm section of an auger drilling installation

    Energy Technology Data Exchange (ETDEWEB)

    Levkovich, P.E.; Kiseleve, E.I.; Krutilin, V.I.; Manzhula, I.T.; Ovsiannikov, P.A.; Savich, N.S.; Tverezyi, Iu.F.

    1981-01-01

    A worm section of an auger drilling installation, comprising columns arranged in parallel and adapters for decreasing the disturbance of the walls of the wells, is characterized in that for the purpose of decreasing the consumption of energy, the adapter for the decrease in the disturbance in the walls of the wells is made in the form of a cylindrical cover with longitudinal windows, arranged on a segment of the length of the worm, with which each cover is positioned rigidly in order to prevent it from shifting lengthwise by means of a support, reinforced on the shaft of the worm. Cylindrical covers are interconnected by a connection element.

  15. A study on the worm gear deficiencies in MOV actuators

    International Nuclear Information System (INIS)

    An MOV(Motor Operated Valve) is a valve system which is operated by an electric motor. The actuator in an MOV is composed of a motor, a worm, a worm gear and bearings. Faults of these components affect the performance of MOVs. Therefore detecting the faults of components before their break will contribute greatly to the safe operation of power plants. However it is very difficult to inspect the components without disassembly. In this paper, we diagnose the worm gear by examining motor torque signature, since the condition of the worm gear is related to the motor torque signature. We tested a worn gear and broken teeth. The rotating parts such as the valve shaft was reviewed and the actuator was checked additionally. For the tests, a simulator was designed and manufactured

  16. Metagenomic Analysis of Microbial Symbionts in a Gutless Worm

    Energy Technology Data Exchange (ETDEWEB)

    Woyke, Tanja; Teeling, Hanno; Ivanova, Natalia N.; Hunteman, Marcel; Richter, Michael; Gloeckner, Frank Oliver; Boeffelli, Dario; Barry, Kerrie W.; Shapiro, Harris J.; Anderson, Iain J.; Szeto, Ernest; Kyrpides, Nikos C.; Mussmann, Marc; Amann, Rudolf; Bergin, Claudia; Ruehland, Caroline; Rubin, Edward M.; Dubilier, Nicole

    2006-05-01

    Symbioses between bacteria and eukaryotes are ubiquitous, yet our understanding of the interactions driving these associations is hampered by our inability to cultivate most host-associated microbes. Here we use a metagenomic approach to describe four co-occurring symbionts from the marine oligochaete Olavius algarvensis, a worm lacking a mouth, gut and nephridia. Shotgun sequencing and metabolic pathway reconstruction revealed that the symbionts are sulphur-oxidizing and sulphate-reducing bacteria, all of which are capable of carbon fixation, thus providing the host with multiple sources of nutrition. Molecular evidence for the uptake and recycling of worm waste products by the symbionts suggests how the worm could eliminate its excretory system, an adaptation unique among annelid worms. We propose a model that describes how the versatile metabolism within this symbiotic consortium provides the host with an optimal energy supply as it shuttles between the upper oxic and lower anoxic coastal sediments that it inhabits.

  17. Shrimp aquaculture in low salinity water feeded with worm flavor

    Directory of Open Access Journals (Sweden)

    Wenceslao Valenzuela Quiñónez

    2012-09-01

    Full Text Available Shrimp aquaculture in Sinaloa is one of the top economic enterprises, generating many jobs and earns significant incomes every year. Shrimp feed is an essential part of maintaining healthy production. In this initial approach of shrimp growth in low salinity water, were tested two formulas of animal protein composed of 40% (APL1 and 20% (APL2 worm protein, a commercial diet, and no supplementary feed. Physicochemical parameters did not have a direct influence in shrimpbehavior. After six weeks of experimentation, shrimp fed with commercial diet had a weight gain 20% higher than those feed with worm protein. There were no significantly differences between sizes with respect to 40% animal protein and 20% animal protein with the commercial diet (P  0.05. However, shrimp fed worm protein had lower mortality. The use of worm protein could be an option to maintain a high quantity of shrimp reared in low salinity waters.

  18. Mathematical model for spreading dynamics of social network worms

    International Nuclear Information System (INIS)

    In this paper, a mathematical model for social network worm spreading is presented from the viewpoint of social engineering. This model consists of two submodels. Firstly, a human behavior model based on game theory is suggested for modeling and predicting the expected behaviors of a network user encountering malicious messages. The game situation models the actions of a user under the condition that the system may be infected at the time of opening a malicious message. Secondly, a social network accessing model is proposed to characterize the dynamics of network users, by which the number of online susceptible users can be determined at each time step. Several simulation experiments are carried out on artificial social networks. The results show that (1) the proposed mathematical model can well describe the spreading dynamics of social network worms; (2) weighted network topology greatly affects the spread of worms; (3) worms spread even faster on hybrid social networks

  19. WormBase: methods for data mining and comparative genomics.

    Science.gov (United States)

    Harris, Todd W; Stein, Lincoln D

    2006-01-01

    WormBase is a comprehensive repository for information on Caenorhabditis elegans and related nematodes. Although the primary web-based interface of WormBase (http:// www.wormbase.org/) is familiar to most C. elegans researchers, WormBase also offers powerful data-mining features for addressing questions of comparative genomics, genome structure, and evolution. In this chapter, we focus on data mining at WormBase through the use of flexible web interfaces, custom queries, and scripts. The intended audience includes users wishing to query the database beyond the confines of the web interface or fetch data en masse. No knowledge of programming is necessary or assumed, although users with intermediate skills in the Perl scripting language will be able to utilize additional data-mining approaches. PMID:16988424

  20. Basic definitions for discrete modeling of computer worms epidemics

    Directory of Open Access Journals (Sweden)

    P. Guevara

    2015-04-01

    Full Text Available The information technologies have evolved in such a way that communication between computers or hosts has become common, so much that the worldwide organization (governments and corporations depends on it; what could happen if these computers stop working for a long time is catastrophic. Unfortunately, networks are attacked by malware such as viruses and worms that could collapse the system. This has served as motivation for the formal study of computer worms and epidemics to develop strategies for prevention and protection; this is why in this paper, before analyzing epidemiological models, a set of formal definitions based on set theory and functions is proposed for describing 21 concepts used in the study of worms. These definitions provide a basis for future qualitative research on the behavior of computer worms, and quantitative for the study of their epidemiological models.

  1. Hybrid Epidemics - A Case Study on Computer Worm Conficker

    OpenAIRE

    Changwang Zhang; Shi Zhou; Chain, Benjamin M.

    2014-01-01

    Conficker is a computer worm that erupted on the Internet in 2008. It is unique in combining three different spreading strategies: local probing, neighbourhood probing, and global probing. We propose a mathematical model that combines three modes of spreading: local, neighbourhood, and global, to capture the worm's spreading behaviour. The parameters of the model are inferred directly from network data obtained during the first day of the Conficker epidemic. The model is then used to explore ...

  2. Aquatic worm reactor for improved sludge processing and resource recovery

    OpenAIRE

    Hendrickx, T.L.G.

    2009-01-01

    Municipal waste water treatment is mainly achieved by biological processes. These processes produce huge volumes of waste sludge (up 1.5 million m3/year in the Netherlands). Further processing of the waste sludge involves transportation, thickening and incineration. A decrease in the amount of waste sludge would be both environmentally and economically attractive. Aquatic worms can be used to reduce the amount of waste sludge. After predation by the worms, the amount of final sludge is lower....

  3. Partial purification and characterization of Ascaridia galli diagnostic worm antigen.

    Science.gov (United States)

    Abdel Rahman, Eman H; Khalil, Fathia A M

    2005-08-01

    Partial purification of Ascaridia galli whole worm extract was conducted by Cyanogen bromide Sepharose 4B immunoaffinity column chromatography. The resulted fraction was characterized by sodium dodecyle sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and isoelectric focusing. The fraction was found to be consisted of six bands of 207 KDa, 157 KDa. 110 KDa, 103 KDa, 76 KDa and 41 KDa. This profile was compared with that of whole worm and excretory-secretory antigens. Both antigens were resolved into multiple bands in both high and low molecular weight ranges. The isoelectric focusing of the fraction displayed 8 bands of isoelectric points 7.5, 7.0, 6.8, 6.5, 6.2, 5.8. 5.3 and 4.6. The potency of this fraction in the diagnosis of natural ascaridiosis in chickens was assessed by ELISA compared with that of whole worm and ES antigens. The affinity purified fraction showed higher potentials in the diagnosis of A. galli infection in chickens than whole worm antigen at any sera dilution and than ES antigen at high sera dilutions. While ES antigen of the worms revealed higher diagnostic capabilities than whole worm extract. The current research recommends utilization of the affinity isolated fraction in the diagnosis of natural ascaridiosis in chickens. PMID:16083065

  4. Social behaviour and collective motion in plant-animal worms.

    Science.gov (United States)

    Franks, Nigel R; Worley, Alan; Grant, Katherine A J; Gorman, Alice R; Vizard, Victoria; Plackett, Harriet; Doran, Carolina; Gamble, Margaret L; Stumpe, Martin C; Sendova-Franks, Ana B

    2016-02-24

    Social behaviour may enable organisms to occupy ecological niches that would otherwise be unavailable to them. Here, we test this major evolutionary principle by demonstrating self-organizing social behaviour in the plant-animal, Symsagittifera roscoffensis. These marine aceol flat worms rely for all of their nutrition on the algae within their bodies: hence their common name. We show that individual worms interact with one another to coordinate their movements so that even at low densities they begin to swim in small polarized groups and at increasing densities such flotillas turn into circular mills. We use computer simulations to: (i) determine if real worms interact socially by comparing them with virtual worms that do not interact and (ii) show that the social phase transitions of the real worms can occur based only on local interactions between and among them. We hypothesize that such social behaviour helps the worms to form the dense biofilms or mats observed on certain sun-exposed sandy beaches in the upper intertidal of the East Atlantic and to become in effect a super-organismic seaweed in a habitat where macro-algal seaweeds cannot anchor themselves. Symsagittifera roscoffensis, a model organism in many other areas in biology (including stem cell regeneration), also seems to be an ideal model for understanding how individual behaviours can lead, through collective movement, to social assemblages. PMID:26911961

  5. Mosquito infection responses to developing filarial worms.

    Directory of Open Access Journals (Sweden)

    Sara M Erickson

    Full Text Available Human lymphatic filariasis is a mosquito-vectored disease caused by the nematode parasites Wuchereria bancrofti, Brugia malayi and Brugia timori. These are relatively large roundworms that can cause considerable damage in compatible mosquito vectors. In order to assess how mosquitoes respond to infection in compatible mosquito-filarial worm associations, microarray analysis was used to evaluate transcriptome changes in Aedes aegypti at various times during B. malayi development. Changes in transcript abundance in response to the different stages of B. malayi infection were diverse. At the early stages of midgut and thoracic muscle cell penetration, a greater number of genes were repressed compared to those that were induced (20 vs. 8. The non-feeding, intracellular first-stage larvae elicited few differences, with 4 transcripts showing an increased and 9 a decreased abundance relative to controls. Several cecropin transcripts increased in abundance after parasites molted to second-stage larvae. However, the greatest number of transcripts changed in abundance after larvae molted to third-stage larvae and migrated to the head and proboscis (120 induced, 38 repressed, including a large number of putative, immunity-related genes (approximately 13% of genes with predicted functions. To test whether the innate immune system of mosquitoes was capable of modulating permissiveness to the parasite, we activated the Toll and Imd pathway controlled rel family transcription factors Rel1 and Rel2 (by RNA interference knockdown of the pathway's negative regulators Cactus and Caspar during the early stages of infection with B. malayi. The activation of either of these immune signaling pathways, or knockdown of the Toll pathway, did not affect B. malayi in Ae. aegypti. The possibility of LF parasites evading mosquito immune responses during successful development is discussed.

  6. Navigating molecular worms inside chemical labyrinths.

    Science.gov (United States)

    Haranczyk, M; Sethian, J A

    2009-12-22

    Predicting whether a molecule can traverse chemical labyrinths of channels, tunnels, and buried cavities usually requires performing computationally intensive molecular dynamics simulations. Often one wants to screen molecules to identify ones that can pass through a given chemical labyrinth or screen chemical labyrinths to identify those that allow a given molecule to pass. Because it is impractical to test each molecule/labyrinth pair using computationally expensive methods, faster, approximate methods are used to prune possibilities, "triaging" the ability of a proposed molecule to pass through the given chemical labyrinth. Most pruning methods estimate chemical accessibility solely on geometry, treating atoms or groups of atoms as hard spheres with appropriate radii. Here, we explore geometric configurations for a moving "molecular worm," which replaces spherical probes and is assembled from solid blocks connected by flexible links. The key is to extend the fast marching method, which is an ordered upwind one-pass Dijkstra-like method to compute optimal paths by efficiently solving an associated Eikonal equation for the cost function. First, we build a suitable cost function associated with each possible configuration, and second, we construct an algorithm that works in ensuing high-dimensional configuration space: at least seven dimensions are required to account for translational, rotational, and internal degrees of freedom. We demonstrate the algorithm to study shortest paths, compute accessible volume, and derive information on topology of the accessible part of a chemical labyrinth. As a model example, we consider an alkane molecule in a porous material, which is relevant to designing catalysts for oil processing. PMID:20018716

  7. MULTI-AGENT SYSTEM FOR WORM DETECTION AND CONTAINMENT IN METROPOLITAN AREA NETWORKS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Active worms can cause widespread damages at so high a speed that effectively precludes human-directed reaction, and patches for the worms are always available after the damages have been caused, whichhas elevated them selfto a first-class security threat to Metropolitan Area Networks (MAN). Multi-agent sys-tem for Worm Detection and Containment in MAN (MWDCM) is presented to provide a first-class auto-matic reaction mechanism that automatically applies containment strategies to block the propagation of theworms and to protect MAN against worm scan that wastes a lot of network bandwidth and crashes therouters. Its user agent is used to detect the known worms. Worm detection agent and worm detection correla-tion agent use two-stage based decision method to detect unknown worms. They adaptively study the access-ing in the whole network and dynamically change the working parameters to detect the unknown worms.MWDCM confines worm infection within a macro-cell or a micro-cell of the metropolitan area networks, therest of the accesses and hosts continue functioning without disruption. MWDCM integrates Worm DetectionSystem (WDS) and network management system. Reaction measures can be taken by using Simple NetworkManagement Protocol (SNMP) interface to control broadband access server as soon as the WDS detect theactive worm. MWDCM is very effective in blocking random scanning worms. Simulation results indicatethat high worm infection rate of epidemics can be avoided to a degree by MWDCM blocking the propagationof the worms.

  8. Research on the Propagation Models and Defense Techniques of Internet Worms

    Institute of Scientific and Technical Information of China (English)

    Tian-Yun Huang

    2008-01-01

    Internet worm is harmful to network security, and it has become a research hotspot in recent years. A thorough survey on the propagation models and defense techniques of Internet worm is made in this paper. We first give its strict definition and discuss the working mechanism. We then analyze and compare some repre sentative worm propagation models proposed in recent years, such as K-M model, two-factor model, worm-anti worm model (WAW), firewall-based model, quarantine based model and hybrid benign worm-based model, etc. Some typical defense techniques such as virtual honeypot, active worm prevention and agent-oriented worm defense, etc, are also discussed. The future direction of the worm defense system is pointed out.

  9. Higher throughput high resolution multi-worm tracker

    Science.gov (United States)

    Javer, Avelino; Li, Kezhi; Gyenes, Bertalan; Brown, Andre; Behavioural Genomics Team

    2015-03-01

    We have developed a high throughput imaging system for tracking multiple nematode worms at high resolution. The tracker consists of 6 cameras mounted on a motorized gantry so that up to 48 plates (each with approximately 30 worms) can be imaged without user intervention. To deal with the high data rate of the cameras we use real time processing to find worms and only save the immediately surrounding pixels. The system is also equipped with automatic oxygen and carbon dioxide control for observing stimulus response behaviour. We will describe the design and performance of the new system, some of the challenges of truly high throughput behaviour recording, and report preliminary results on inter-individual variation in behaviour as well as a quantitative analysis of C. elegans response to hypoxia, oxygen reperfusion, and carbon dioxide. Funding provided by the Medical Research Council.

  10. Diet of Worms Emended: An Update of Polychaete Feeding Guilds

    Science.gov (United States)

    Jumars, Peter A.; Dorgan, Kelly M.; Lindsay, Sara M.

    2015-01-01

    Polychaetes are common in most marine habitats and dominate many infaunal communities. Functional guild classification based on taxonomic identity and morphology has linked community structure to ecological function. The functional guilds now include osmotrophic siboglinids as well as sipunculans, echiurans, and myzostomes, which molecular genetic analyses have placed within Annelida. Advances in understanding of encounter mechanisms explicitly relate motility to feeding mode. New analyses of burrowing mechanics explain the prevalence of bilateral symmetry and blur the boundary between surface and subsurface feeding. The dichotomy between microphagous deposit and suspension feeders and macrophagous carnivores, herbivores, and omnivores is further supported by divergent digestive strategies. Deposit feeding appears to be limited largely to worms longer than 1 cm, with juveniles and small worms in general restricted to ingesting highly digestible organic material and larger, rich food items, blurring the macrophage-microphage dichotomy that applies well to larger worms.

  11. Continuous-time quantum Monte Carlo using worm sampling

    Science.gov (United States)

    Gunacker, P.; Wallerberger, M.; Gull, E.; Hausoel, A.; Sangiovanni, G.; Held, K.

    2015-10-01

    We present a worm sampling method for calculating one- and two-particle Green's functions using continuous-time quantum Monte Carlo simulations in the hybridization expansion (CT-HYB). Instead of measuring Green's functions by removing hybridization lines from partition function configurations, as in conventional CT-HYB, the worm algorithm directly samples the Green's function. We show that worm sampling is necessary to obtain general two-particle Green's functions which are not of density-density type and that it improves the sampling efficiency when approaching the atomic limit. Such two-particle Green's functions are needed to compute off-diagonal elements of susceptibilities and occur in diagrammatic extensions of the dynamical mean-field theory and in efficient estimators for the single-particle self-energy.

  12. Ascaris lumbricoides: reinfection in children bearing an established worm burden

    Directory of Open Access Journals (Sweden)

    Fausto E. Lima Pereira

    1991-12-01

    Full Text Available To clarify the existance of reinfection in children bearing an established Ascaris lumbricoides infection, the authors evaluated the weight and the length of worms collected from ten cases of ascaridiasis. The worm burden was greater than 27 worms in nine cases. In seven cases the weight and the length of worms showed little variation, with unimodal distribution of values, suggesting that all the worms in each case belong to the same population, originated from a single brood infection or from successive infections over small time intervals. In three cases there was great variation in worm size indicated by the different values for the means and medians and by the high values for the standard deviation and coefficient of variation. In these three cases there was a bimodal distribution of worm's size suggesting the coexistance of two distinct populations: one, less numerous, composed of mature worms and the other, more numerous, composed ofimmature worms, in two cases, and two distinct populations of immature worms in one case. The existance of worms in different stages of maturation indicates that the less mature population was acquired when the mature worms were established in the gut. These results indicate that the reinfection with Ascaris in children bearing an established infection is not rare and resistance induced by a preexisting infection is not the rule.Para tentar esclarecer a existência de reinfecção em crianças portadoras de ascaridíase já estabelecida, foram avaliados o peso e o comprimento dos vermes colhidos em 10 casosde ascaridíase, em nove dos quais a carga parasitária foi maior do que 27 vermes. Em sete casos o peso e o comprimento dos vermes apresentaram pouca variação, com distribuição unimodal dos valores, sugerindo assim pertencerem todos a uma mesma população originada de uma única infecção ou de infecções repetidas com intervalos muito curtos. Em três casos, o peso e o comprimento dos vermes

  13. Commwarrior worm propagation model for smart phone networks

    Institute of Scientific and Technical Information of China (English)

    XIA Wei; LI Zhao-hui; CHEN Zeng-qiang; YUAN Zhu-zhi

    2008-01-01

    Commwarrior worm is capable of spreading through both Bluetooth and multimedia messaging service (MMS) in smart phone networks. According to the propagation characteristics of Bluetooth and MMS, we built the susceptible- exposed-infected-recovered-dormancy (SEIRD) model for the Bluetooth and MMS hybrid spread mode and performed the stability analysis. The simulation results show good correlation with our theoretical analysis and demonstrate the effectiveness of this dynamic propagation model. On the basis of the SEIRD model, we further discuss at length the influence of the propagation parameters such as user gather density in groups, moving velocity of smart phone, the time for worm to replicate itself, and other interrelated parameters on the propagation of the virus. On the basis of these analytical and simulation results, some feasible control strategies will be proposed to restrain the spread of mobile worm such as commwarrior on smart phone network.

  14. Preparation of Pickering double emulsions using block copolymer worms.

    Science.gov (United States)

    Thompson, Kate L; Mable, Charlotte J; Lane, Jacob A; Derry, Mathew J; Fielding, Lee A; Armes, Steven P

    2015-04-14

    The rational formulation of Pickering double emulsions is described using a judicious combination of hydrophilic and hydrophobic block copolymer worms as highly anisotropic emulsifiers. More specifically, RAFT dispersion polymerization was utilized to prepare poly(lauryl methacrylate)-poly(benzyl methacrylate) worms at 20% w/w solids in n-dodecane and poly(glycerol monomethacrylate)-poly(2-hydroxypropyl methacrylate)-poly(benzyl methacrylate) worms at 13% w/w solids in water by polymerization-induced self-assembly (PISA). Water-in-oil-in-water (w/o/w) double emulsions can be readily prepared with mean droplet diameters ranging from 30 to 80 μm using a two-stage approach. First, a w/o precursor emulsion comprising 25 μm aqueous droplets is prepared using the hydrophobic worms, followed by encapsulation within oil droplets stabilized by the hydrophilic worms. The double emulsion droplet diameter and number of encapsulated water droplets can be readily varied by adjusting the stirring rate employed during the second stage. For each stage, the droplet volume fraction is relatively high at 0.50. The double emulsion nature of the final formulation was confirmed by optical and fluorescence microscopy studies. Such double emulsions are highly stable to coalescence, with little or no change in droplet diameter being detected over storage at 20 °C for 10 weeks as judged by laser diffraction. Preliminary experiments indicate that the complementary o/w/o emulsions can also be prepared using the same pair of worms by changing the order of homogenization, although somewhat lower droplet volume fractions were required in this case. Finally, we demonstrate that triple and even quadruple emulsions can be formulated using these new highly anisotropic Pickering emulsifiers. PMID:25834923

  15. Localization of Waves without Bistability Worms in Nematic Electroconvection

    CERN Document Server

    Riecke, H; Riecke, Hermann; Granzow, Glen D.

    1998-01-01

    A general localization mechanism for waves in dissipative systems is identified that does not require the bistability of the basic state and the nonlinear plane-wave state. The mechanism explains the two-dimensional localized wave structures (`worms') that recently have been observed in experiments on electroconvection in nematic liquid crystals where the transition to extended waves is supercritical. The mechanism accounts for the propagation direction of the worms and certain aspects of their interaction. The dynamics of the localized waves can be steady or irregular.

  16. Age-related worm load and worm fecundity patterns in human populations, as indicated by schistosome circulating antigens

    Directory of Open Access Journals (Sweden)

    Polman Katja

    1998-01-01

    Full Text Available Recently, our group determined the relationship between serum CAA levels and fecal egg counts in two foci with very intense Schistosoma mansoni transmission: Maniema (Zaire, an area endemic for S. mansoni since several decades, and Ndombo (Senegal, where transmission has only been established since a few years. The objective was to study and compare age-related worm load and worm fecundity patterns in these two different endemic settings. Here, we will summarize the most important findings and conclusions of this study.

  17. SEX PHEROMONE FOR CRANBERRY BLOSSOM WORM, EPIGLAE APIATA.

    Science.gov (United States)

    The cranberry blossom worm, Epiglaea apiata (Grote) (Lepidoptera: Noctuidae), is a major pest of cranberries, Vaccinium macrocarpon (Aitan), in New Jersey. The sex pheromone of this insect was identified to be a blend of (Z)-9-hexadecenyl acetate (Z9-16:Ac), (Z)-9-tetradecenyl acetate (Z9-14:Ac), a...

  18. Opinion Dynamics Driven by Leaders, Media, Viruses and Worms

    Science.gov (United States)

    Tuncay, Çağlar

    A model on the effects of leader, media, viruses, worms, and other agents on the opinion of individuals is developed and utilized to simulate the formation of consensus in society and price in market via excess between supply and demand. The effects of some time varying drives (harmonic and hyperbolic) are also investigated.

  19. Opinion dynamics driven by leaders, media, viruses and worms

    CERN Document Server

    Tuncay, C

    2006-01-01

    A model on the effects of leader, media, viruses, and worms and other agents on the opinion of individuals is developed and utilized to simulate the formation of consensus in society and price in market via excess between supply and demand. Effects of some time varying drives, (harmonic and hyperbolic) are also investigated. Key words: Opinion; Leader; Media; Market; Buyers; Sellers; Excess

  20. The Vicious Worm - A One Health cysticercosis advocacy information tool

    DEFF Research Database (Denmark)

    Saarnak, Christopher; Trevisan, Chiara; Mejer, Helena;

    The Vicious Worm: A computer-based program advocating for prevention and control of Taenia solium cysticercosis – a zoonotic tapeworm disease - widespread and emerging in many low income countries due to increased pork production and bad hygiene. Available at www.theviciousworm.org + Google Play...

  1. Metagenomics of the Methane Ice Worm, Hesiocaeca methanicola

    Science.gov (United States)

    Goodwin, K. D.; Edsall, L.; Xin, W.; Head, S. R.; Gelbart, T.; Wood, A. M.; Gaasterland, T.

    2012-12-01

    The methane ice worm (Hesiocaeca methanicola) is a polychaete found on methane hydrate deposits for which there appears to be no publically available genomic or metagenomic data. Methane ice worms were collected in 2009 by the Johnson-Sea-Link submersible (543m depth; N 27:44.7526 W 91:13.3168). Next-generation sequencing (HiSeq2000) was applied to samples of tissue and gut contents. A subset of the assembled data (40M reads, randomly selected) was run through MG-RAST. Preliminary results for the gut content (1,269,153 sequences, average length 202 bp) indicated that 0.1% of the sequences contained ribosomal RNA genes with the majority (67%) classified as Bacteria, a relatively small per cent (1.4%) as Archae, and 31% as Eukaryota. Campylobacterales was the predominant order (14%), with unclassified (7.5%) and Desulfobacterales (4%) being the next dominant. Preliminary results for the worm tissue (2,716,461 sequences, average length 241 bp) indicated that the majority of sequences were Eukaryota (73%), with 256 sequences classified as phylum Annelida and 58% of those belonging to class Polychaeta. For the bacterial sequences obtained from the tissue samples, the predominant order was Actinomycetales (2.7%). For both the tissue and gut content samples, the majority of proteins were classified as clustering-based subsystems. This preliminary analysis will be compared to an assembly consisting of 40M of the highest quality reads.; methane ice worms on methane hydrate

  2. The Worm Process for the Ising Model is Rapidly Mixing

    Science.gov (United States)

    Collevecchio, Andrea; Garoni, Timothy M.; Hyndman, Timothy; Tokarev, Daniel

    2016-09-01

    We prove rapid mixing of the worm process for the zero-field ferromagnetic Ising model, on all finite connected graphs, and at all temperatures. As a corollary, we obtain a fully-polynomial randomized approximation scheme for the Ising susceptibility, and for a certain restriction of the two-point correlation function.

  3. Making sense of genomes of parasitic worms: Tackling bioinformatic challenges.

    Science.gov (United States)

    Korhonen, Pasi K; Young, Neil D; Gasser, Robin B

    2016-01-01

    Billions of people and animals are infected with parasitic worms (helminths). Many of these worms cause diseases that have a major socioeconomic impact worldwide, and are challenging to control because existing treatment methods are often inadequate. There is, therefore, a need to work toward developing new intervention methods, built on a sound understanding of parasitic worms at molecular level, the relationships that they have with their animal hosts and/or the diseases that they cause. Decoding the genomes and transcriptomes of these parasites brings us a step closer to this goal. The key focus of this article is to critically review and discuss bioinformatic tools used for the assembly and annotation of these genomes and transcriptomes, as well as various post-genomic analyses of transcription profiles, biological pathways, synteny, phylogeny, biogeography and the prediction and prioritisation of drug target candidates. Bioinformatic pipelines implemented and established recently provide practical and efficient tools for the assembly and annotation of genomes of parasitic worms, and will be applicable to a wide range of other parasites and eukaryotic organisms. Future research will need to assess the utility of long-read sequence data sets for enhanced genomic assemblies, and develop improved algorithms for gene prediction and post-genomic analyses, to enable comprehensive systems biology explorations of parasitic organisms. PMID:26956711

  4. Round worm in the ear: A clinical rarity

    Directory of Open Access Journals (Sweden)

    Vidya Bhushan Rangappa

    2014-01-01

    Full Text Available Foreign body in otolaryngology practice is a common scenario. There have been very few documentations of a worm entering the ear through the Eustachian tube. We hereby report a very interesting such case and also discuss the possible cause postulated for such events.

  5. Performance Analysis of Cell-Phone Worm Spreading in Cellular Networks through Opportunistic Communications

    OpenAIRE

    YAHUI, W.; Deng, S; Huang, H; Deng, Y.

    2012-01-01

    Worms spreading directly between cell-phones over short-range radio (Bluetooth, WiFi, etc.) are increasing rapidly. Communication by these technologies is opportunistic and has very close relation with the social characteristics of the phone carriers. In this paper, we try to evaluate the impact of different characteristics on the spreading performance of worms. On the other hand, the behaviors of worms may have certain impact, too. For example, worms may make phones be completely dysfunc...

  6. WORM: A general-purpose input deck specification language

    International Nuclear Information System (INIS)

    Using computer codes to perform criticality safety calculations has become common practice in the industry. The vast majority of these codes use simple text-based input decks to represent the geometry, materials, and other parameters that describe the problem. However, the data specified in input files are usually processed results themselves. For example, input decks tend to require the geometry specification in linear dimensions and materials in atom or weight fractions, while the parameter of interest might be mass or concentration. The calculations needed to convert from the item of interest to the required parameter in the input deck are usually performed separately and then incorporated into the input deck. This process of calculating, editing, and renaming files to perform a simple parameter study is tedious at best. In addition, most computer codes require dimensions to be specified in centimeters, while drawings or other materials used to create the input decks might be in other units. This also requires additional calculation or conversion prior to composition of the input deck. These additional calculations, while extremely simple, introduce a source for error in both the calculations and transcriptions. To overcome these difficulties, WORM (Write One, Run Many) was created. It is an easy-to-use programming language to describe input decks and can be used with any computer code that uses standard text files for input. WORM is available, via the Internet, at worm.lanl.gov. A user's guide, tutorials, example models, and other WORM-related materials are also available at this Web site. Questions regarding WORM should be directed to wormatlanl.gov

  7. Screw-worm eradication in the Americas - Overview

    International Nuclear Information System (INIS)

    Screw-worms (Cochliomyia hominivorax, Coquerel) are found only in the Americas, and are known, therefore, as the New World Screw-worm (NWS). The larval stages of the fly feed on the living flesh of their host. A screw-worm infestation can kill an adult animal in 7-10 days if not treated. All warm-blooded animals are affected including man. Although screw-worms had long been recognised as a severe pest of animals in the southwestern United States, they had never been detected east of the Mississippi River before 1933. In July 1933, screw-worms were transported on infested cattle to Georgia and became established east of the Mississippi River. Screw-worms spread quickly in the southeastern United States and were able to overwinter in southern Florida. Being new to the region, they were quickly recognised as a severe pest with a tremendous economic impact on livestock production. The livestock owners in the southeastern United States immediately noticed an increase in the number of animal deaths and increased costs of insecticides, veterinary medicines, veterinary services, inspection and handling. At the same time, they observed a decrease in animal weights and in milk production. Due to these observations, the livestock industry in the southeastern United States requested help in controlling screw-worms. Because of these requests, the research community became interested in control and eradication measures for this pest. Early work by Crushing and Patton in 1933 recognised that C. hominivorax was an obligatory animal parasite and different from the secondary blowfly, Cochliomyia macellaria. In 1934, the US Department of Agriculture (USDA), Agricultural Research Service (ARS) opened a research station in Valdosa, Georgia, and E.W. Laake and E.F. Knipling were assigned to work there. In September 1935, R.C. Bushland was hired by ARS to do research related to screw-worms at an ARS Research Laboratory in Dallas, Texas. Melvin and Bushland in 1936 developed artificial

  8. Production of worm-gear speed reducers for NPP charging machines

    International Nuclear Information System (INIS)

    Main features and performance of three types of worm-gear speed reducers applied in WWER-1000 charging machines are presented and described. All types of reducers have a single worm; worm gearings in them are clearance free. The reducer design provides for minimal cost of production preparation and requires minimal application of special production equipment

  9. Desenvolupament d'un joc per a dispositius Android: WhackaWorm

    OpenAIRE

    García Solsona, David

    2016-01-01

    Projecte de desenvolupament d'un joc per a Android: WhackaWorm, basat en la famosa màquina de recreatives, Whackamole. Proyecto de desarrollo de un juego para Android: Whack Worm, basado en la famosa máquina de recreativas, Whackamole. Project to develop a game for Android: Worm Whack based on famous arcade machine, Whackamole.

  10. QuantWorm: a comprehensive software package for Caenorhabditis elegans phenotypic assays.

    Directory of Open Access Journals (Sweden)

    Sang-Kyu Jung

    Full Text Available Phenotypic assays are crucial in genetics; however, traditional methods that rely on human observation are unsuitable for quantitative, large-scale experiments. Furthermore, there is an increasing need for comprehensive analyses of multiple phenotypes to provide multidimensional information. Here we developed an automated, high-throughput computer imaging system for quantifying multiple Caenorhabditis elegans phenotypes. Our imaging system is composed of a microscope equipped with a digital camera and a motorized stage connected to a computer running the QuantWorm software package. Currently, the software package contains one data acquisition module and four image analysis programs: WormLifespan, WormLocomotion, WormLength, and WormEgg. The data acquisition module collects images and videos. The WormLifespan software counts the number of moving worms by using two time-lapse images; the WormLocomotion software computes the velocity of moving worms; the WormLength software measures worm body size; and the WormEgg software counts the number of eggs. To evaluate the performance of our software, we compared the results of our software with manual measurements. We then demonstrated the application of the QuantWorm software in a drug assay and a genetic assay. Overall, the QuantWorm software provided accurate measurements at a high speed. Software source code, executable programs, and sample images are available at www.quantworm.org. Our software package has several advantages over current imaging systems for C. elegans. It is an all-in-one package for quantifying multiple phenotypes. The QuantWorm software is written in Java and its source code is freely available, so it does not require use of commercial software or libraries. It can be run on multiple platforms and easily customized to cope with new methods and requirements.

  11. Hop-by-HopWorm Propagation with Carryover Epidemic Model in Mobile Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jun-Won Ho

    2015-10-01

    Full Text Available In the internet, a worm is usually propagated in a random multi-hop contact manner. However, the attacker will not likely select this random multi-hop propagation approach in a mobile sensor network. This is because multi-hop worm route paths to random vulnerable targets can be often breached due to node mobility, leading to failure of fast worm spread under this strategy. Therefore, an appropriate propagation strategy is needed for mobile sensor worms. To meet this need, we discuss a hop-by-hop worm propagation model in mobile sensor networks. In a hop-by-hop worm propagation model, benign nodes are infected by worm in neighbor-to-neighbor spread manner. Since worm infection occurs in hop-by-hop contact, it is not substantially affected by a route breach incurred by node mobility. We also propose the carryover epidemic model to deal with the worm infection quota deficiency that might occur when employing an epidemic model in a mobile sensor network. We analyze worm infection capability under the carryover epidemic model. Moreover, we simulate hop-by-hop worm propagation with carryover epidemic model by using an ns-2 simulator. The simulation results demonstrate that infection quota carryovers are seldom observed where a node’s maximum speed is no less than 20 m/s.

  12. The Opportunistic Transmission of Wireless Worms between Mobile Devices

    CERN Document Server

    Rhodes, C J

    2008-01-01

    The ubiquity of portable wireless-enabled computing and communications devices has stimulated the emergence of malicious codes (wireless worms) that are capable of spreading between spatially proximal devices. The potential exists for worms to be opportunistically transmitted between devices as they move around, so human mobility patterns will have an impact on epidemic spread. The scenario we address in this paper is proximity attacks from fleetingly in-contact wireless devices with short-range communication range, such as Bluetooth-enabled smart phones. An individual-based model of mobile devices is introduced and the effect of population characteristics and device behaviour on the outbreak dynamics is investigated. We show through extensive simulations that in the above scenario the resulting mass-action epidemic models remain applicable provided the contact rate is derived consistently from the underlying mobility model. The model gives useful analytical expressions against which more refined simulations ...

  13. Bioaccumulation and biological effects of cigarette litter in marine worms

    OpenAIRE

    Stephanie L. Wright; Darren Rowe; Reid, Malcolm J; Thomas, Kevin V.; Galloway, Tamara S.

    2015-01-01

    Marine debris is a global environmental issue. Smoked cigarette filters are the predominant coastal litter item; 4.5 trillion are littered annually, presenting a source of bioplastic microfibres (cellulose acetate) and harmful toxicants to marine environments. Despite the human health risks associated with smoking, little is known of the hazards cigarette filters present to marine life. Here we studied the impacts of smoked cigarette filter toxicants and microfibres on the polychaete worm Hed...

  14. Shrimp aquaculture in low salinity water feeded with worm flavor

    OpenAIRE

    Wenceslao Valenzuela Quiñónez; Gerardo Rodríguez-Quiroz; Héctor Manuel Esparza Leal; Eusebio Nava Pérez

    2012-01-01

    Shrimp aquaculture in Sinaloa is one of the top economic enterprises, generating many jobs and earns significant incomes every year. Shrimp feed is an essential part of maintaining healthy production. In this initial approach of shrimp growth in low salinity water, were tested two formulas of animal protein composed of 40% (APL1) and 20% (APL2) worm protein, a commercial diet, and no supplementary feed. Physicochemical parameters did not have a direct influence in shrimpbehavior. After six we...

  15. Taxonomy Icon Data: hemichordates (Acorn worm) [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available hemichordates (Acorn worm) Glandiceps hacksi Hemichordata Glandiceps_hacksi_L.png Glandiceps_hack...si_NL.png Glandiceps_hacksi_S.png Glandiceps_hacksi_NS.png http://biosciencedbc.jp/taxonomy_ic...on/icon.cgi?i=Glandiceps+hacksi&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Glandiceps+hacksi&t=NL ...http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Glandiceps+hacksi&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Glandiceps+hacksi&t=NS ...

  16. Polyanhydride Nanoparticle Delivery Platform Dramatically Enhances Killing of Filarial Worms.

    Directory of Open Access Journals (Sweden)

    Andrea M Binnebose

    Full Text Available Filarial diseases represent a significant social and economic burden to over 120 million people worldwide and are caused by endoparasites that require the presence of symbiotic bacteria of the genus Wolbachia for fertility and viability of the host parasite. Targeting Wolbachia for elimination is a therapeutic approach that shows promise in the treatment of onchocerciasis and lymphatic filariasis. Here we demonstrate the use of a biodegradable polyanhydride nanoparticle-based platform for the co-delivery of the antibiotic doxycycline with the antiparasitic drug, ivermectin, to reduce microfilarial burden and rapidly kill adult worms. When doxycycline and ivermectin were co-delivered within polyanhydride nanoparticles, effective killing of adult female Brugia malayi filarial worms was achieved with approximately 4,000-fold reduction in the amount of drug used. Additionally the time to death of the macrofilaria was also significantly reduced (five-fold when the anti-filarial drug cocktail was delivered within polyanhydride nanoparticles. We hypothesize that the mechanism behind this dramatically enhanced killing of the macrofilaria is the ability of the polyanhydride nanoparticles to behave as a Trojan horse and penetrate the cuticle, bypassing excretory pumps of B. malayi, and effectively deliver drug directly to both the worm and Wolbachia at high enough microenvironmental concentrations to cause death. These provocative findings may have significant consequences for the reduction in the amount of drug and the length of treatment required for filarial infections in terms of patient compliance and reduced cost of treatment.

  17. Ecological succession of a Jurassic shallow-water ichthyosaur fall.

    Science.gov (United States)

    Danise, Silvia; Twitchett, Richard J; Matts, Katie

    2014-01-01

    After the discovery of whale fall communities in modern oceans, it has been hypothesized that during the Mesozoic the carcasses of marine reptiles created similar habitats supporting long-lived and specialized animal communities. Here, we report a fully documented ichthyosaur fall community, from a Late Jurassic shelf setting, and reconstruct the ecological succession of its micro- and macrofauna. The early 'mobile-scavenger' and 'enrichment-opportunist' stages were not succeeded by a 'sulphophilic stage' characterized by chemosynthetic molluscs, but instead the bones were colonized by microbial mats that attracted echinoids and other mat-grazing invertebrates. Abundant cemented suspension feeders indicate a well-developed 'reef stage' with prolonged exposure and colonization of the bones prior to final burial, unlike in modern whale falls where organisms such as the ubiquitous bone-eating worm Osedax rapidly destroy the skeleton. Shallow-water ichthyosaur falls thus fulfilled similar ecological roles to shallow whale falls, and did not support specialized chemosynthetic communities. PMID:25205249

  18. Analysis of Two-Worm Interaction Model in Heterogeneous M2M Network

    Directory of Open Access Journals (Sweden)

    Jinhua Ma

    2015-10-01

    Full Text Available With the rapid development of M2M (Machine-to-Machine networks, the damages caused by malicious worms are getting more and more serious. By considering the influences of the network heterogeneity on worm spreading, we are the first to study the complex interaction dynamics between benign worms and malicious worms in heterogeneous M2M network. We analyze and compare three worm propagation models based on different immunization schemes. By investigating the local stability of the worm-free equilibrium, we obtain the basic reproduction number R0 . Besides, by using suitable Lyapunov functions, we prove that the worm-free equilibrium is globally asymptotically stable if R0 ≤ 1 , otherwise unstable. The dynamics of worm models is completely determined by R0 . In the absence of birth, death and users’ treatment, we obtain the final size formula of worms. This study shows that the nodes with higher node degree are more susceptible to be infected than those with lower node degree. In addition, the effects of various immunization schemes are studied. Numerical simulations verify our theoretical results. The research results are meaningful for us to further understand the spread of worms in heterogeneous M2M network, and enact effectual control tactics.

  19. Routes of uptake of diclofenac, fluoxetine, and triclosan into sediment-dwelling worms.

    Science.gov (United States)

    Karlsson, Maja V; Marshall, Stuart; Gouin, Todd; Boxall, Alistair B A

    2016-04-01

    The present study investigated the route and degree of uptake of 2 ionizable pharmaceuticals (diclofenac and fluoxetine) and 1 ionizable compound used in personal care products (triclosan) into the sediment-dwelling worm Lumbriculus variegatus. Studies were done on complete worms ("feeding") and worms where the head was absent ("nonfeeding") using (14) C-labeled ingredients. Biota sediment accumulation factors (BSAF), based on uptake of (14) C, for feeding worms increased in the order fluoxetine (0.3) triclosan (9), which is correlated with a corresponding increase in log octanol-water partition coefficient. Biota sediment accumulation factor estimates are representative of maximum values because the degree of biotransformation in the worms was not quantified. Although no significant differences were seen between the uptake of diclofenac and that of fluoxetine in feeding and nonfeeding worms, uptake of the more hydrophobic antimicrobial, triclosan, into the feeding worms was significantly greater than that in the nonfeeding worms, with the 48-h BSAF for feeding worms being 36% higher than that for the nonfeeding worms. The results imply that dietary uptake contributes to the uptake of triclosan, which may be a result of the high hydrophobicity of the compound. Models that estimate exposure of ionizable substances may need to consider uptake from both the water column and food, particularly when assessing risks from dynamic exposures to organic contaminants. Environ Toxicol Chem 2016;35:836-842. © 2015 SETAC. PMID:25892588

  20. Study on the Faults of the Worm Gear in the Actuator

    International Nuclear Information System (INIS)

    The actuator of the motor-operated valve (MOV) is the system which transfers the torque from the electrical motor to the stem. It is composed of the spur gear set, the worm-worm gear set, bearings and so on. Among them, the condition of the worm-worm gear set affect most on the performance of the actuator such as the efficiency. Therefore, the diagnosing defects and maintaining the performance of the worm-worm gear set contributes to the safe operation of power plants. However, it is very difficult to inspect it without disassembly. In this paper, non-intrusive diagnostic methods are developed to identify the defects which commonly occur: the wear of the gear teeth, broken teeth and the eccentricity of the assembly. Motor torque signals are used as the basic diagnostic signatures and the methods are verified with the various experiments

  1. Schistosoma mansoni: acquired resistance in mice by implantation of young irradiated worms into the portal system

    International Nuclear Information System (INIS)

    In two distinct experiments immature S.mansoni worms (LE strain, Belo Horizonte, Brazil), aged 20 days, obtained from the portal system of white outbred mice, were irradiated with 14 and 4 Krad, respectively. Afterwards, the worms were directly inoculated into the portal vein of normal mice. Inoculation was performed with 20 irradiated worms per animal. Fifty days after inoculation, the mice that received 4 and 14 Krad-irradiated worms and their respective controls were infected with S.mansoni cercariae (LE strain), by transcutaneous route. Twenty days after this challenge infection, the animals were sacrificed and perfused for mature irradiated (90-day-old) and immature (20-day-old) worm counts. Analysis of the results showed that statistically significant protection against cercariae occurred in both groups with irradiated worms. (author)

  2. : acquired resistance in mice by implantation of young irradiated worms into the portal system

    Directory of Open Access Journals (Sweden)

    Paulo Marcos Z. Coelho

    1989-02-01

    Full Text Available In two distinct experiments, immature S. mansoni worms (LE strain, Belo Horizonte, Brazil, aged 20 days, obtained from the portal system of white outbred mice, were irradiated with 14 and 4 Krad, respectively. Afterwards, the worms were directly inoculated into the portal vein of normal mice. Inoculation was performed with 20 irradiated worms per animal. Fifty days after inoculation, the mice that received 4 and 14 Krad-irradiated worms and their respective controls were infected with S. mansoni cercariae (LE strain, by transcutaneous route. Twenty days after this challenge infection, the animals were sacrificed and perfused for mature irradiated (90-day-old and immature (20-day-old worm counts. Analysis of the results showed that statistically significant protection against cercariae occurred in both groups with irradiated worms.

  3. Electro-worming: The Behaviors of Caenorhabditis (C.) elegans in DC and AC Electric Fields

    CERN Document Server

    Chuang, Han-Sheng; Dabbish, Nooreen; Bau, Haim

    2010-01-01

    The video showcases how C. elegans worms respond to DC and AC electrical stimulations. Gabel et al (2007) demonstrated that in the presence of DC and low frequency AC fields, worms of stage L2 and larger propel themselves towards the cathode. Rezai et al (2010) have demonstrated that this phenomenon, dubbed electrotaxis, can be used to control the motion of worms. In the video, we reproduce Rezai's experimental results. Furthermore, we show, for the first time, that worms can be trapped with high frequency, nonuniform electric fields. We studied the effect of the electric field on the nematode as a function of field intensity and frequency and identified a range of electric field intensities and frequencies that trap worms without apparent adverse effect on their viability. Worms tethered by dielectrophoresis (DEP) avoid blue light, indicating that at least some of the nervous system functions remain unimpaired in the presence of the electric field. DEP is useful to dynamically confine nematodes for observati...

  4. A NOVEL METHOD FOR NETWORK WORM DETECTION BASED ON WAVELET PACKET ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    Liao Mingtao; Zhang Deyun; Hou Lin

    2006-01-01

    Objective To detect unknown network worm at its early propagation stage. Methods On the basis of characteristics of network worm attack, the concept of failed connection flow (FCT) was defined. Based on wavelet packet analysis of FCT time series, this method computed the energy associated with each wavelet packet of FCT time series, transformed the FCT time series into a series of energy distribution vector on frequency domain, then a trained K-nearest neighbor (KNN) classifier was applied to identify the worm. Results The experiment showed that the method could identify network worm when the worm started to scan. Compared to theoretic value, the identification error ratio was 5.69%. Conclusion The method can detect unknown network worm at its early propagation stage effectively.

  5. THE WORMS COMPOST - EFFECTIVE FERTILIZER FOR IMPROVING DEGRADED SOILS

    Directory of Open Access Journals (Sweden)

    Larisa CREMENEAC

    2013-01-01

    Full Text Available Management of organic waste is a difficult, complex and intractable in Moldova, according to international standards. Acute problem of organic matter from livestock sector waste is generated by storing them in unauthorized areas. Organic waste management strategies require different methods. One of them is organic waste bio conversion technology by worm’s cultivation. As the main natural wealth of the Republic of Moldova, soil requires a special care. Agriculture, in particular, should pay attention to the soil’s humus and nutrient status – and restore losses of humus and the nutrients used by crops. This requires measures to improve soil fertility. Land use provides, first of all return losses of humus and nutrients used by plants. Therefore measures required to improve soil fertility. The essence of the research was to highlight the role of worms compost improve the soil. To this end, in ETS "Maximovca" was organized an experiment that included three groups (two - experimental, to fund worms compost and one - control the natural background. Observations on soil fertility have been conducted over three years. The soil samples were collected by usual methods determined values of organic matter and humus. The results of the investigations, to determine the values of organic matter and humus samples collected from surface and depth 15 cm exceeded that of the sample control group to 29,7%; 11,4% and 34,3%; 37,1% in experimental group I and 9,3%; 11,6% and 45,5%; 45,5% in experimental group II. Therefore, worms compost embedded in a dose of 3-4 tons / ha during three years, has improved the fertility of the soil

  6. Towards global Guinea worm eradication in 2015: the experience of South Sudan.

    Science.gov (United States)

    Awofeso, Niyi

    2013-08-01

    For centuries, the Guinea worm parasite (Dracunculus medinensis) has caused disabling misery, infecting people who drink stagnant water contaminated with the worm's larvae. In 2012, there were 542 cases of Guinea worm reported globally, of which 521 (96.1%) were reported in South Sudan. Protracted civil wars, an inadequate workforce, neglect of potable water provision programs, suboptimal Guinea worm surveillance and case containment, and fragmented health systems account for many of the structural and operational factors encumbering South Sudan's Guinea worm eradication efforts. This article reviews the impacts of six established Guinea worm control strategies in South Sudan: (1) surveillance to determine actual caseload distribution and trends in response to control measures; (2) educating community members from whom worms are emerging to avoid immersing affected parts in sources of drinking water; (3) filtering potentially contaminated drinking water using cloth filters or filtered drinking straws; (4) treating potentially contaminated surface water with the copepod larvicide temephos (Abate); (5) providing safe drinking water from boreholes or hand-dug wells; and (6) containment of transmission through voluntary isolation of each patient to prevent contamination of drinking water sources, provision of first aid, and manual extraction of the worm. Surveillance, community education, potable water provision, and case containment remain weak facets of the program. Abate pesticide is not a viable option for Guinea worm control in South Sudan. In light of current case detection and containment trends, as well as capacity building efforts for Guinea worm eradication, South Sudan is more likely to eradicate Guinea worm by 2020, rather than by 2015. The author highlights areas in which substantial improvements are required in South Sudan's Guinea worm eradication program, and suggests improvement strategies. PMID:23623648

  7. Comparative study on presentation of biliary ascariasis with dead and living worms

    Directory of Open Access Journals (Sweden)

    Alam Shahinul

    2010-01-01

    Full Text Available Background/Aim: Ascariasis is a common parasitic infestation in Asia and Latin America. The most serious presentation is biliary and pancreatic ascariasis (BPA. The aim of the present study was to compare the clinical presentation of BPA with dead worms with that with living worms. Materials and Methods: We included 138 consecutive cases of BPA that occured during the period January 2005 to July 2009. All the patients had endoscopically proven BPA consisting of living or dead worms. Comparison was done by chi-square and independent t tests. Results: The age (mean ± SD of the patients was 36.8 ± 16.1 years. Prevalence ratio between male and female patients was 1:5. Ninety eight patients contained living worms and 40 had dead worms. Males were more prone to develop dead worm BPA. The commonest presentation was biliary colic (131; 94.9%; others were acute cholangitis (30; 21.7%, obstructive jaundice (19; 13.8%, choledocholithiasis (20; 14.5%, acute pancreatitis (10; 7.2%, acute cholecystitis (6; 4.3%, liver abscess (2; 1.4%, hepatolithiasis (3; 2.2%, stricture of common bile duct (2; 1.4%, pancreatic abscess (1; 0.7% and cirrhosis of liver (1; 0.7%. Choledocholithiasis, hepatolithiasis, liver abscess and cirrhosis were associated only with dead worms. We could successfully remove all the worms with endoscopic interventions, but 5 patients required surgical intervention as there were strictures and stones within the biliary tree or Ascaris were in gallbladder. Recurrences of stone and cholangitis occurred only in those with dead worms. Conclusion: Biliary ascariasis with dead worms is more dangerous than that with living worms. Endoscopic or surgical intervention may be required repeatedly in those with dead worms.

  8. Comparative Study on Presentation of Biliary Ascariasis with Dead and Living Worms

    OpenAIRE

    Alam, Shahinul; Mustafa, Golam; Rahman, Salimur; Kabir, Shamsul A.; Rashid, Harun O.; Khan, Mobin

    2010-01-01

    Background/Aim: Ascariasis is a common parasitic infestation in Asia and Latin America. The most serious presentation is biliary and pancreatic ascariasis (BPA). The aim of the present study was to compare the clinical presentation of BPA with dead worms with that with living worms. Materials and Methods: We included 138 consecutive cases of BPA that occured during the period January 2005 to July 2009. All the patients had endoscopically proven BPA consisting of living or dead worms. Comparis...

  9. Pet roundworms and hookworms: A continuing need for global worming

    Directory of Open Access Journals (Sweden)

    Traversa Donato

    2012-05-01

    Full Text Available Abstract Ascarids and ancylostomatids are the most important parasites affecting dogs and cats worldwide, in terms of diffusion and risk for animal and human health. Different misconceptions have led the general public and pet owners to minimize the importance of these intestinal worms. A low grade of interest is also registered among veterinary professions, although there is a significant merit in keeping our guard up against these parasites. This article reviews current knowledge of ascarids and ancylostomatids, with a special focus on pathogenicity, epidemiology and control methods in veterinary and human medicine.

  10. Cooperative Automated Worm Response and Detection Immune Algorithm

    CERN Document Server

    Kim, Jungwon; Aickelin, Uwe; McLeod, Julie

    2010-01-01

    The role of T-cells within the immune system is to confirm and assess anomalous situations and then either respond to or tolerate the source of the effect. To illustrate how these mechanisms can be harnessed to solve real-world problems, we present the blueprint of a T-cell inspired algorithm for computer security worm detection. We show how the three central T-cell processes, namely T-cell maturation, differentiation and proliferation, naturally map into this domain and further illustrate how such an algorithm fits into a complete immune inspired computer security system and framework.

  11. Self-Propagating Worms in Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Giannetsos, Thanassis; Dimitriou, Tassos; Prasad, Neeli R.

    2009-01-01

    Malicious code is defined as software designed to execute attacks on software systems. This work demonstrates the possibility of executing malware on wireless sensor nodes that are based on the von Neumann architecture. This is achieved by exploiting a buffer overflow vulnerability to smash...... the call stack, intrude a remote node over the radio channel and, eventually, completely take control of it. Then we show how the malware can be crafted to become a self-replicating worm that broadcasts itself and propagates over the network hop-by-hop, infecting all the nodes....

  12. The research on the modeling of dual-cone double enveloping hourglass worm gear pair

    Directory of Open Access Journals (Sweden)

    LI Shaoxiang

    2013-04-01

    Full Text Available Up to now there is no specialized,efficient,general-purpose modeling method of dual-cone double enveloping hourglass worm gear pair.In this paper,based on the spatial meshing theory,a parameterized mathematical model of the dual-cone double enveloping hourglass worm gear pair is established,which is simplified as a digitized modeling method based on six basic parameters of the worm gear pair.Virtual machining modeling plug-in programming is achieved through the solidworks development platform.The results show that this modeling method can make the hourglass worm modeling more convenient,accurate and fast.

  13. Meandering worms: mechanics of undulatory burrowing in muds.

    Science.gov (United States)

    Dorgan, Kelly M; Law, Chris J; Rouse, Greg W

    2013-04-22

    Recent work has shown that muddy sediments are elastic solids through which animals extend burrows by fracture, whereas non-cohesive granular sands fluidize around some burrowers. These different mechanical responses are reflected in the morphologies and behaviours of their respective inhabitants. However, Armandia brevis, a mud-burrowing opheliid polychaete, lacks an expansible anterior consistent with fracturing mud, and instead uses undulatory movements similar to those of sandfish lizards that fluidize desert sands. Here, we show that A. brevis neither fractures nor fluidizes sediments, but instead uses a third mechanism, plastically rearranging sediment grains to create a burrow. The curvature of the undulating body fits meander geometry used to describe rivers, and changes in curvature driven by muscle contraction are similar for swimming and burrowing worms, indicating that the same gait is used in both sediments and water. Large calculated friction forces for undulatory burrowers suggest that sediment mechanics affect undulatory and peristaltic burrowers differently; undulatory burrowing may be more effective for small worms that live in sediments not compacted or cohesive enough to extend burrows by fracture. PMID:23446526

  14. Bio-inspired microfluidics: The case of the velvet worm

    Science.gov (United States)

    Concha, Andres; Mellado, Paula; Morera-Brenes, Bernal; Sampaio-Costa, Cristiano; Mahadevan, L.; Monge-Najera, Julian

    The rapid squirt of a proteinaceous slime jet endow velvet worms (Onychophora) with a unique mechanism for defense from predators and for capturing prey by entangling them in a disordered web that immobilizes their target. However, to date neither qualitative nor quantitative descriptions have been provided for this unique adaptation. We have investigated the mechanism that allows velvet worms the fast oscillatory motion of their oral papillae and the exiting liquid jet that oscillates with frequencies f ~ 30 - 60 Hz. Using anatomical images and high speed videography, we show that even without fast muscular action of the papilla, a strong contraction of the slime reservoir and the geometry of the reservoir-papilla system suffices to accelerate the slime to speeds up to v ~ 5 m /s in about Δt ~ 60 ms. A theoretical analysis and a physical simulacrum allow us to infer that this fast oscillatory motion is the result of an elastohydrodynamic instability driven by the interplay between the elasticity of oral papillae and the fast unsteady flow during squirting. We propose several applications that can be implemented using this instability, ranging from high-throughput droplet production, printing, and micro-nanofiber production among others. A.C was partially supported by Fondecyt Grant 11130075.

  15. Performance Analysis of Cell-Phone Worm Spreading in Cellular Networks through Opportunistic Communications

    Directory of Open Access Journals (Sweden)

    YAHUI, W.

    2012-05-01

    Full Text Available Worms spreading directly between cell-phones over short-range radio (Bluetooth, WiFi, etc. are increasing rapidly. Communication by these technologies is opportunistic and has very close relation with the social characteristics of the phone carriers. In this paper, we try to evaluate the impact of different characteristics on the spreading performance of worms. On the other hand, the behaviors of worms may have certain impact, too. For example, worms may make phones be completely dysfunctional and these phones can be seen as killed. We study the impact of the killing speed. Using the Markov model, we propose some theoretical models to evaluate the spreading performance in different cases. Simulation results show the accuracy of our models. Numerical results show that if users do not believe the data coming from others easily, the worms may bring less damage. Surprisingly, if the users are more willing to install the anti-virus software, the worms may bring bigger damage when the software becomes to be outdated with high probability. Though the worms can bring big damage on the network temporarily by killing phones rapidly, numerical results show that this behavior may decrease the total damage in the long time. Therefore, killing nodes more rapidly may be not optimal for worms.

  16. Worms Expelled With the Urine From a Bosniak Cyst III of the Left Kidney.

    Science.gov (United States)

    Yang, Jie; Li, Pu; Su, Chuan; Zhang, Jia-Yi; Gu, Min

    2016-07-01

    An old fishman presented with left lumbago and finding worms in his urine. Type-B ultrasonic inspection and computed tomography scan found a Bosniak cyst III, containing several wire-like elements, in the middle of the left kidney. Expelled worms were confirmed to be Dioctophyma renale. After two courses of albendazole, the man was cured. PMID:27015940

  17. Valorization of waste streams, "From food by-products to worm biomass"

    NARCIS (Netherlands)

    Laarhoven, B.; Elissen, H.J.H.; Temmink, B.G.; Buisman, C.J.N.

    2013-01-01

    A new technology is investigated to produce a high quality animal feed source by converting safe industrial food wastes into worm biomass. The freshwater worm Lumbriculus variegatus (common name: blackworm) has been selected for this purpose. This species can be used to reduce and concentrate munici

  18. Global dynamics of a novel multi-group model for computer worms

    International Nuclear Information System (INIS)

    In this paper, we study worm dynamics in computer networks composed of many autonomous systems. A novel multi-group SIQR (susceptible-infected-quarantined-removed) model is proposed for computer worms by explicitly considering anti-virus measures and the network infrastructure. Then, the basic reproduction number of worm R0 is derived and the global dynamics of the model are established. It is shown that if R0 is less than or equal to 1, the disease-free equilibrium is globally asymptotically stable and the worm dies out eventually, whereas, if R0 is greater than 1, one unique endemic equilibrium exists and it is globally asymptotically stable, thus the worm persists in the network. Finally, numerical simulations are given to illustrate the theoretical results. (general)

  19. A Potential Approach of Internet Worm Propagation Based on P2P

    Institute of Scientific and Technical Information of China (English)

    YAO Yu; LUO Xingrui; GAO Fuxiang; YU Ge

    2006-01-01

    Various kinds of active worms have been plunging into the network flows, which make the Internet security problem more serious. Our research on a potential propagation approach of active worms, P2P-based propagation approach, is given in this paper. To measure the propagating performance of our approach, the SEI (Susceptible-Exposed- Infected) propagation model is presented. It proves that with the idea of pure P2P architecture, worms can be hidden in the early stage of propagation, and then infect most of the hosts in a shorter period. By comparing our SEI propagation model with the Simple Epidemic Model, we observe that the size of a worm is a significant parameter which can affect the propagating performance. When the size of the worm becomes large, our approach can still show an excellent propagating performance.

  20. Ethnophysiology and herbal treatments of intestinal worms in Dominica, West Indies.

    Science.gov (United States)

    Quinlan, Marsha B; Quinlan, Robert J; Nolan, Justin M

    2002-04-01

    In rural Dominican ethnophysiology worms reside in a human organ called the 'worm bag'. Unchecked, worms can cause illness by growing in size and number, spreading out of the worm bag and into other organs. In this study of 'bush medicine', we use a measure of cognitive salience in free-listing tasks, which reveals five plants commonly used to treat intestinal worms. These were Ambrosia hispida (Asteraceae), Aristolochia trilobata (Aristlochiaceae), Chenopodium ambrosioides (Chenopodiaceae), Portulaca oleracea (Portulacaceae), and Artemisia absinthium (Asteraceae). Bioactive compounds appear to be present in all of these plants. The cognitive salience of these plant remedies coupled with evidence of biochemical properties suggest that they provide efficacious treatments for controlling intestinal parasite loads. PMID:11891089

  1. Nonvolatile WORM memory devices based on polymethacrylate with azoanthraquinone group

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A novel polymethacrylate containing azoanthraquinone chromophore in the side chain(PMAzoaq6) was synthesized and characterized.An electronic memory device having the indium-tin oxide(ITO)/PMAzoaq6/Al sandwich structure was fabricated and its electrical bistability was investigated.The as-fabricated device was initially found to be at the OFF state and the switching threshold voltage was 1.5 V.After undergoing the OFF-to-ON transition,the device maintains the high conducting state(ON state) even after turning off the electrical power and applying a reverse bias.The device exhibits a write-once-read-many-times(WORM) memory effect with a high ON/OFF current ratio of up to 105 and a long retention time in both ON and OFF states,which demonstrated that the synthetic azoanthraquinone-containing polymer possesses a high potential to become polymeric memory devices.

  2. Worm-like instability of a vibrated sessile drop

    Science.gov (United States)

    Hemmerle, A.; Froehlicher, G.; Bergeron, V.; Charitat, T.; Farago, J.

    2015-07-01

    We study the effects of vertical sinusoidal vibrations on a liquid droplet with a low surface tension (ethanol) deposited on a solid substrate. In a precise range of amplitudes and frequencies, the drop exhibits a dramatic worm-like shape instability with a strong symmetry breaking, comparable to the one observed by Pucci et al. (Phys. Rev. Lett., 106 (2011) 024503) on a vibrated floating lens. However, the geometry of our system is much simpler since it does not involve the oscillation and deformation of a liquid-liquid-air contact line. We show that the Faraday waves appearing on the surface of the droplet control its shape and we draw a systematic phase diagram of the instability. A simple theoretical model allows us to derive a relation between the elongation of the droplet and the amplitude of the Faraday wave, in good agreement with measurements of both quantities.

  3. Graphical method for profiling hob mill that generate cycloid worms

    Science.gov (United States)

    Teodor, V.; Berbinschi, S.; Baroiu, N.; Oancea, N.

    2015-11-01

    The hob mill for generating ordered curls of cycloid surface with non involute profiles may be profiled based on the fundamental theorems of surface enveloping - Olivier - as surface reciprocally enveloping with point like contact. In this paper, is proposed a methodology based on a complementary theorem of the surface enveloping in a graphical expression developed in a graphical design environment - CATIA. The graphical method presented in this paper is developed in two stages: determining of the rack gear model based on the solid model of the surface to be generated, using an original algorithm, following this, based on 3D modelling is determined the solid model of the primary peripheral surface of the hob mill. An application for a cycloid worm is presented - a central screw of helical pumps. In order to prove the quality of method, the analytical and graphical solutions are comparatively presented.

  4. A GENERATIVE CAD MODEL OF A WORM GEAR MESHING

    Directory of Open Access Journals (Sweden)

    Angelika WRONKOWICZ

    2014-03-01

    Full Text Available This article introduces the term of a generative CAD model, its origins and, thus, a need of creating such a type of models. A process of generative model creation as well as specific forms of knowledge recording applied in the implementation phase in various CAD systems are briefly discussed. The example of a worm gear meshing realized by the CATIA software encapsulates the methodology of generative model construction. Sources and types of knowledge for design and construction required for development of the aforementioned model as well as the UML language as a method of formal knowledge recording are presented. The concept of model creation, i.e. assumptions and the structure as well as logic of the model operation are described. Also, the paper addresses selected elements of the project that present the manner in which the model was constructed.

  5. An unusual and unsettling place for a worm.

    Science.gov (United States)

    Samuel, M I; Taylor, C

    2010-07-01

    A 56-year-old man presented complaining of urinary frequency, passing urine eight times per day, urethral irritation and dysuria. Investigations showed no evidence of urinary tract infection or sexually transmitted infections. Three months later he presented, again complaining of increased urinary frequency and urethral irritation. He brought with him a urine specimen containing a small 'worm', 2 mm in length, identified as a drain fly (or moth fly) larva, of the genus Psychoda (dipterous flies). Psychoda lay eggs in organically polluted water such as sewage plants, sink drains or on decaying vegetables and fruits. Urogenital myiasis may arise from hatching of larvae near the urethral opening and ascending migration along the urethra with consequent urethritis. Following larval identification, ivermectin was prescribed and the man's symptoms improved after six weeks. PMID:20852207

  6. Integumentary L-histidine transport in a euryhaline polychaete worm: Regulatory roles of calcium and cadmium in the transport event

    DEFF Research Database (Denmark)

    Ahearn, Heather Rae Hammers; Ahearn, Gregory A.; Gomme, Jørgen

    Epithelial transport, integument, polychaete worm, Nereis succinea, Annelida, transport regulation, calcium, cadmium, heavy metal......Epithelial transport, integument, polychaete worm, Nereis succinea, Annelida, transport regulation, calcium, cadmium, heavy metal...

  7. Community perception and role in prevention of Guinea worm disease.

    Science.gov (United States)

    Omar, M A; Sufi, Q M; Gamba-Osiga, A

    1993-01-01

    In Kitgum district of northern Uganda in 1992, natural group and focus group discussions and key informant interviews were conducted to examine the knowledge, attitudes, practices, and beliefs of the people concerning Guinea Worm disease (GW disease) and its transmission, prevention, and treatment. Most people could describe the cause and treatment of Coo (local name of GW disease). More than 58% thought dirty or bad water was the main cause of Coo. 63.2% believed that drinking contaminated water was the cause. 13.1% did not know the cause of GW disease. Few people clearly understood how GW is transmitted. People received treatment from the nearest health unit (42%), traditional healers (34%), self-medication (16%), and drug shops (8%). 55.3% of key informants believed that Coo cases had increased. The perceived reasons for the increase were drinking dirty water (42.8%), migration (38.1%), no medicine (9.5%), and increased population (4.8%). Suggestions for community action to halt transmission of GW included provision of safe water, educating each other, boiling water, and filtering water. The community perceived that the government and nongovernmental organizations could drill new boreholes, bring in medications, repair broken boreholes, protect water sources, and provide education to stop the spread of GW disease. Water sources were shallow wells, streams, rivers, valley dams, and boreholes. 77.3% of boreholes did not work. Most other water sources were inadequately protected from GW infestation. Some community members perceived boiling water as tedious and difficult. Most people thought that there was nothing or little they could do to prevent contamination of water sources. Few had heard health education messages about Guinea Worm disease. Many people wanted the use of plays, drama, and videos in villages to communicate GW prevention messages. PMID:7516675

  8. Trichuris suis: thiol protease activity from adult worms.

    Science.gov (United States)

    Hill, D E; Sakanari, J A

    1997-01-01

    Trichuris suis, the whipworm of swine, causes anemia, weight loss, anorexia, mucohemorrhagic diarrhea, and death in heavy infections. A zinc metalloprotease has been suggested to play a role in the severe enteric pathology associated with infection and the infiltration of opportunistic bacteria into deeper tissues in the swine colon. In this study, a thiol protease from gut extracts of adult T. suis and from excretory/secretory components (E/S) of adult worms was characterized using fluorogenic peptide substrates and protein substrate gels. The protease cleaved the fluorogenic substrate Z-Phe-Arg-AMC, and this cleavage was completely inhibited by the thiol protease inhibitors E-64, leupeptin, Z-Phe-Ala-CH2F, and Z-Phe-Arg-CH2F. Gelatin substrate gels and fluorescence assays using both the gut and the stichosome extracts and E/S revealed enhanced activity when 2 mM dithiothreitol or 5 mM cysteine was included in the incubation buffer, and optimal activity was seen over a pH range of 5.5 to 8.5. Incubation of gut extracts or E/S material with inhibitors of aspartic, serine, or metalloproteases had no effect on the cleavage of Z-Phe-Arg-AMC. Thiol protease activity was found in extracts of gut tissue but not in the extracts of stichocytes of adult worms. N-terminal amino acid sequencing of the protease revealed sequence homologies with cathepsin B-like thiol protease identified from parasitic and free-living nematodes. PMID:9024202

  9. Can the restrictive harvest period policy conserve mopane worms in Southern Africa? A bio-economic modelling approach

    OpenAIRE

    Wisdom Akpalu; Edwin Muchapondwa; Precious Zikhali

    2007-01-01

    Imbrasia Belina also known as the mopane worm, like other edible insects and caterpillars, is a vital source of protein to Southern African countries. The worms live and graze on mopane trees, which occupy agricultural land. With increasing commercialization of the worm, the management of the worm, which was hitherto organized as a common property resource, has degraded to a near open access. In this paper, a simple bio-economic modeling approach has been taken to show that, for some optimal ...

  10. Mesh theory of angle modified dual tori double-enveloping toroidal worm drive

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper, the meshing theory of the angle modified hourglass worm drive is enriched and developed. The ordinary condition of the angle modification is derived and the physical significance of the modification is interpreted. A normal section methodology is proposed for meshing analysis, which can be used to compute the normal distance near a singular meshing point of a conjugate surface couple. By means of the method and after analyzing the normal transversals, it is specified that the worm helicoid, the nominal former contact zone and the new contact zone intersect each other along the locus of singular points of the instantaneous contact lines of an angle-modified worm pair. As a result, it is explained clearly that those three osculate each other but the osculations are different in degree. Moreover, the mechanism of removing the twice-contacted zone from the worm gear tooth surface is clarified and the reason of shortening the worm working length is also elucidated. With the help of the theory described in the present paper and the thorough and systematic research on the relevant meshing characteristics, the angle modified dual tori double-enveloping toroidal worm drive has been shown to be an excellent new-fashioned hourglass worm set.

  11. Comparison of sup(115m)Cd accumulation from sediments and sea water by polychaete worms

    International Nuclear Information System (INIS)

    To know the role played by marine sediments in influencing the fate of discharged metals, (1) the interaction of metals between sediments and deposit-feeder marine worms (Nereis japonica), and (2) uptake and excretion of metals by worms were examined by laboratory experiments using sup(115m)Cd. Worms directly in contact with sup(115m)Cd-sediments accumulated sup(115m)Cd six times more than worms that were not in contact with the sup(115m)Cd sediments during the 8 days of experimentation and 12% of sup(115m)Cd in sediments were noted to be transfered to worms per unit. Comparing the concentration factor of 22 (from sea water) with accumulation from sediments, it was assumed that sup(115m)Cd in sediments would give the effect of 1/200 to the accumulation of sup(115m)Cd by worms in sea water to the accumulation of sup(115m)Cd. Further, to simulate these results close to that occuring in the natural ecosystem, the distribution of sup(115m)Cd in sea water, sediments and alga were also examined by means of a curve analysis of the distribution pattern by a three compartment model. It proved that the activity ratios of sup(115m)Cd were 9 for sediments and 21 for alga, which was similar to 22 for worms. (auth.)

  12. Viability of developmental stages of Schistosoma mansoni quantified with xCELLigence worm real-time motility assay (xWORM).

    Science.gov (United States)

    Rinaldi, Gabriel; Loukas, Alex; Brindley, Paul J; Irelan, Jeff T; Smout, Michael J

    2015-12-01

    Infection with helminth parasites causes morbidity and mortality in billions of people and livestock worldwide. Where anthelmintic drugs are available, drug resistance is a major problem in livestock parasites, and a looming threat to public health. Monitoring the efficacy of these medicines and screening for new drugs has been hindered by the lack of objective, high-throughput approaches. Several cell monitoring technologies have been adapted for parasitic worms, including video-, fluorescence-, metabolism enzyme- and impedance-based tools that minimize the screening bottleneck. Using the xCELLigence impedance-based system we previously developed a motility-viability assay that is applicable for a range of helminth parasites. Here we have improved substantially the assay by using diverse frequency settings, and have named it the xCELLigence worm real-time motility assay (xWORM). By utilizing strictly standardized mean difference analysis we compared the xWORM output measured with 10, 25 and 50 kHz frequencies to quantify the motility of schistosome adults (human blood flukes) and hatching of schistosome eggs. Furthermore, we have described a novel application of xWORM to monitor movement of schistosome cercariae, the developmental stage that is infectious to humans. For all three stages, 25 kHz was either optimal or near-optimal for monitoring and quantifying schistosome motility. These improvements in methodology sensitivity should enhance the capacity to screen small compound libraries for new drugs both for schistosomes and other helminth pathogens at large. PMID:26288742

  13. Viability of developmental stages of Schistosoma mansoni quantified with xCELLigence worm real-time motility assay (xWORM

    Directory of Open Access Journals (Sweden)

    Gabriel Rinaldi

    2015-12-01

    Full Text Available Infection with helminth parasites causes morbidity and mortality in billions of people and livestock worldwide. Where anthelmintic drugs are available, drug resistance is a major problem in livestock parasites, and a looming threat to public health. Monitoring the efficacy of these medicines and screening for new drugs has been hindered by the lack of objective, high-throughput approaches. Several cell monitoring technologies have been adapted for parasitic worms, including video-, fluorescence-, metabolism enzyme- and impedance-based tools that minimize the screening bottleneck. Using the xCELLigence impedance-based system we previously developed a motility-viability assay that is applicable for a range of helminth parasites. Here we have improved substantially the assay by using diverse frequency settings, and have named it the xCELLigence worm real-time motility assay (xWORM. By utilizing strictly standardized mean difference analysis we compared the xWORM output measured with 10, 25 and 50 kHz frequencies to quantify the motility of schistosome adults (human blood flukes and hatching of schistosome eggs. Furthermore, we have described a novel application of xWORM to monitor movement of schistosome cercariae, the developmental stage that is infectious to humans. For all three stages, 25 kHz was either optimal or near-optimal for monitoring and quantifying schistosome motility. These improvements in methodology sensitivity should enhance the capacity to screen small compound libraries for new drugs both for schistosomes and other helminth pathogens at large.

  14. Automatic defense against zero-day polymorphic worms in communication networks

    CERN Document Server

    Mohammed, Mohssen

    2013-01-01

    Able to propagate quickly and change their payload with each infection, polymorphic worms have been able to evade even the most advanced intrusion detection systems (IDS). And, because zero-day worms require only seconds to launch flooding attacks on your servers, using traditional methods such as manually creating and storing signatures to defend against these threats is just too slow. Bringing together critical knowledge and research on the subject, Automatic Defense Against Zero-day Polymorphic Worms in Communication Networks details a new approach for generating automated signatures for un

  15. Simulation of worms transmission in computer network based on SIRS fuzzy epidemic model

    Science.gov (United States)

    Darti, I.; Suryanto, A.; Yustianingsih, M.

    2015-03-01

    In this paper we study numerically the behavior of worms transmission in a computer network. The model of worms transmission is derived by modifying a SIRS epidemic model. In this case, we consider that the transmission rate, recovery rate and rate of susceptible after recovery follows fuzzy membership functions, rather than constants. To study the transmission of worms in a computer network, we solve the model using the fourth order Runge-Kutta method. Our numerical results show that the fuzzy transmission rate and fuzzy recovery rate may lead to a changing of basic reproduction number which therefore also changes the stability properties of equilibrium points.

  16. How algae influence sessile marine organisms: The tube worms case of study

    Science.gov (United States)

    Casoli, Edoardo; Bonifazi, Andrea; Ardizzone, Giandomenico; Gravina, Maria Flavia

    2016-09-01

    Tube worms and phytobenthic assemblages in three infralittoral and shallow circalittoral Mediterranean benthic communities developed between 5 and 35 m depth at Punta del Lazzaretto (Giglio Island, Central Thyrrenian sea) were investigated. Despite being three algae-dominated habitats, these displayed different covering both in terms of algal layers and algal morphologies, reflecting different structural organizations. Twenty-eight serpulid taxa have been reported, increasing both diversity and density values from most photophilic to most sciaphilous habitats. Multivariate analyses showed how algal thalli and tube worm assemblages were strongly correlated; substrata are influenced both physically and biologically, providing different conditions for tube worm settlement.

  17. Monosaccharide transport into hemocytes of a sipunculan worm Themiste dyscrita

    International Nuclear Information System (INIS)

    The hemerythrin-containing blood cells, or hemocytes, of the sipunculan worm Themiste dyscrita were found to have a stereospecific and nonconcentrative monosaccharide transport system. The transport system transferred both D-glucose and 3-O-methyl-D-glucose (3-OMG), and transport into cells by this system was rapid, reaching 50% equilibrium in approximately 20 s at 10 degrees C with an initial concentration gradient of 0.1 mM; the contribution to total uptake by simple diffusion was very small. 3-OMG uptake showed saturation kinetics with a low half-saturation constant (Km less than or equal to 0.1 mM). The uptake of labeled 3-OMG by the hemocytes was strongly inhibited by unlabeled 3-OMG, 2-deoxy-D-glucose, alpha- and beta-D-glucose, D-galactose, and D-mannose. It was moderately inhibited by D-xylose, only slightly by alpha-methyl-D-glucoside and D-fructose, and uninhibited by sucrose, L-glucose, or D-sorbitol. Phloretin was more potent than phloridzin in blocking entry of 3-OMG. Cytochalasin B did not bind tightly to the T. dyscrita transporter and was not a potent inhibitor of transport; it half-maximally inhibited 3-OMG transport at 0.1 mM. Therefore, despite some differences the data suggest functional similarities in the mechanism of monosaccharide transport into blood cells of mammals and this invertebrate

  18. Recurrent cholangitis in the tropics: Worm or cast?

    Directory of Open Access Journals (Sweden)

    Jain P

    2010-01-01

    Full Text Available The development of biliary casts is very rare, especially in non-liver transplant patients. The etiology of these casts is uncertain but several factors have been proposed which lead to bile stasis and/or gallbladder hypo-contractility and promote cast formation. Here, we report a 54-year-old male, with diabetes and ischemic heart disease, who presented with recurrent attacks of cholangitis. Magnetic resonance cholangiopancreatography revealed linear T1 hyperintense and T2 hypointense filling defects in the right and left hepatic ducts extending into the common hepatic duct, and a calculus in the lower common bile duct, raising a suspicion of worm in the biliary tree. In view of failed attempts at extraction on endoscopy, patient underwent surgery. At exploration, biliary casts and stones were extracted from the proximal and the second order bile ducts, with the help of intraoperative choledochoscopy and a bilio-enteric anastomosis was accomplished. Although endoscopic retrieval of the biliary cast can be employed as first-line management, surgery should be considered in case it fails.

  19. Serological screening of the Schistosoma mansoni adult worm proteome.

    Directory of Open Access Journals (Sweden)

    Fernanda Ludolf

    2014-03-01

    Full Text Available BACKGROUND: New interventions tools are a priority for schistosomiasis control and elimination, as the disease is still highly prevalent. The identification of proteins associated with active infection and protective immune response may constitute the basis for the development of a successful vaccine and could also indicate new diagnostic candidates. In this context, post-genomic technologies have been progressing, resulting in a more rational discovery of new biomarkers of resistance and antigens for diagnosis. METHODOLOGY/PRINCIPAL FINDINGS: Two-dimensional electrophoresed Schistosoma mansoni adult worm protein extracts were probed with pooled sera of infected and non-infected (naturally resistant individuals from a S. mansoni endemic area. A total of 47 different immunoreactive proteins were identified by mass spectrometry. Although the different pooled sera shared most of the immunoreactive protein spots, nine protein spots reacted exclusively with the serum pool of infected individuals, which correspond to annexin, major egg antigen, troponin T, filamin, disulphide-isomerase ER-60 precursor, actin and reticulocalbin. One protein spot, corresponding to eukaryotic translation elongation factor, reacted exclusively with the pooled sera of non-infected individuals living in the endemic area. Western blotting of two selected recombinant proteins, major egg antigen and hemoglobinase, showed a similar recognition pattern of that of the native protein. CONCLUDING/SIGNIFICANCE: Using a serological proteome analysis, a group of antigens related to the different infection status of the endemic area residents was identified and may be related to susceptibility or resistance to infection.

  20. Functional brain regeneration in the acoel worm Symsagittifera roscoffensis

    Directory of Open Access Journals (Sweden)

    Simon G. Sprecher

    2015-12-01

    Full Text Available The ability of some animals to regrow their head and brain after decapitation provides a striking example of the regenerative capacity within the animal kingdom. The acoel worm Symsagittifera roscoffensis can regrow its head, brain and sensory head organs within only a few weeks after decapitation. How rapidly and to what degree it also reacquires its functionality to control behavior however remains unknown. We provide here a neuroanatomical map of the brain neuropils of the adult S. roscoffensis and show that after decapitation a normal neuroanatomical organization of the brain is restored in the majority of animals. By testing different behaviors we further show that functionality of both sensory perception and the underlying brain architecture are restored within weeks after decapitation. Interestingly not all behaviors are restored at the same speed and to the same extent. While we find that phototaxis recovered rapidly, geotaxis is not restored within 7 weeks. Our findings show that regeneration of the head, sensory organs and brain result in the restoration of directed navigation behavior, suggesting a tight coordination in the regeneration of certain sensory organs with that of their underlying neural circuits. Thus, at least in S. roscoffensis, the regenerative capacity of different sensory modalities follows distinct paths.

  1. Bioaccumulation and biological effects of cigarette litter in marine worms.

    Science.gov (United States)

    Wright, Stephanie L; Rowe, Darren; Reid, Malcolm J; Thomas, Kevin V; Galloway, Tamara S

    2015-01-01

    Marine debris is a global environmental issue. Smoked cigarette filters are the predominant coastal litter item; 4.5 trillion are littered annually, presenting a source of bioplastic microfibres (cellulose acetate) and harmful toxicants to marine environments. Despite the human health risks associated with smoking, little is known of the hazards cigarette filters present to marine life. Here we studied the impacts of smoked cigarette filter toxicants and microfibres on the polychaete worm Hediste diversicolor (ragworm), a widespread inhabitant of coastal sediments. Ragworms exposed to smoked cigarette filter toxicants in seawater at concentrations 60 fold lower than those reported for urban run-off exhibited significantly longer burrowing times, >30% weight loss, and >2-fold increase in DNA damage compared to ragworms maintained in control conditions. In contrast, ragworms exposed to smoked cigarette filter microfibres in marine sediment showed no significant effects. Bioconcentration factors for nicotine were 500 fold higher from seawater than from sediment. Our results illustrate the vulnerability of organisms in the water column to smoking debris and associated toxicants, and highlight the risks posed by smoked cigarette filter debris to aquatic life. PMID:26369692

  2. Methane Ice Worms: Hesiocaeca methanicola Colonizing Fossil Fuel Reserves

    Science.gov (United States)

    Fisher, C. R.; MacDonald, I. R.; Sassen, R.; Young, C. M.; Macko, S. A.; Hourdez, S.; Carney, R. S.; Joye, S.; McMullin, E.

    During a research cruise in July 1997 in the Gulf of Mexico we discovered a gas hydrate approximately 1m thick and over 2m in diameter which had recently breached the sea floor at a depth of 540m. The hydrate surface visible from the submarine was considerably greater than that of any other reported hydrate. Two distinct color bands of hydrate were present in the same mound, and the entire exposed surface of the hydrate was infested (2500 individuals/m2) with 2 to 4 cm-long worms, since described as a new species, Hesiocaecamethanicola, in the polychaete family Hesionidae (Desbruyères and Toulmond 1998). H.methanicola tissue stable isotope values are consistent with a chemoautotrophic food source. No evidence of chemoautotrophic symbionts was detected, but geochemical data support the presence of abundant free living bacteria on the hydrate. The activities of the polychaetes, grazing on the hydrate bacteria and supplying oxygen to their habitats, appears to contribute to the dissolution of hydrates in surface sediments.

  3. Functional brain regeneration in the acoel worm Symsagittifera roscoffensis.

    Science.gov (United States)

    Sprecher, Simon G; Bernardo-Garcia, F Javier; van Giesen, Lena; Hartenstein, Volker; Reichert, Heinrich; Neves, Ricardo; Bailly, Xavier; Martinez, Pedro; Brauchle, Michael

    2015-01-01

    The ability of some animals to regrow their head and brain after decapitation provides a striking example of the regenerative capacity within the animal kingdom. The acoel worm Symsagittifera roscoffensis can regrow its head, brain and sensory head organs within only a few weeks after decapitation. How rapidly and to what degree it also reacquires its functionality to control behavior however remains unknown. We provide here a neuroanatomical map of the brain neuropils of the adult S. roscoffensis and show that after decapitation a normal neuroanatomical organization of the brain is restored in the majority of animals. By testing different behaviors we further show that functionality of both sensory perception and the underlying brain architecture are restored within weeks after decapitation. Interestingly not all behaviors are restored at the same speed and to the same extent. While we find that phototaxis recovered rapidly, geotaxis is not restored within 7 weeks. Our findings show that regeneration of the head, sensory organs and brain result in the restoration of directed navigation behavior, suggesting a tight coordination in the regeneration of certain sensory organs with that of their underlying neural circuits. Thus, at least in S. roscoffensis, the regenerative capacity of different sensory modalities follows distinct paths. PMID:26581588

  4. A SEM study of the reindeer sinus worm (Linguatula arctica

    Directory of Open Access Journals (Sweden)

    Sven Nikander

    2009-01-01

    Full Text Available Pentastomids are a group of peculiar parasitic arthropods, often referred to as tongue worms due to the resemblance of some species to a tongue. Linguatula arctica is the sinus worm of the reindeer (Rangifer tarandus, being the only pentastomid to have a direct life cycle and an ungulate as a definite host. Here, the surface structures and internal anatomy of adult L. arctica are described as seen by scanning electron microscopy (SEM. Sinus worms were collected in the winter 1991-92 in Finnish Lapland. Paranasal cavities of about 80 reindeer were examined and 30 sinus worms were found. The sinus worms had typical Linguatula sp. morphology, being paddle-shaped, transparent, pale yellow, dorsoventrally flattened and pseudosegmented with a long tapering end. Present at the anteroventral part of the cephalothorax was an oral opening with a large, conspicuous, head-like papillar structure. Bilaterally, on both sides of this opening, was a pair of strong curved hooks. The cephalothorax and abdomen had a segmented appearance, as they showed distinct annulation. There was a small cup-shaped sensory organ present at the lateral margin on each annula. The posterior edge of each annula was roughened by tiny spines projecting backwards. Throughout the cuticular surface, small, circular depressions that represented the apical portion of chloride cells. The genital opening of the male was located medioventrally between the tips of the posterior pair of hooks, and that of the female posteroventrally and subterminally. In both sexes, the genital opening was bilaterally flanked by papillar (in males or leaf-like (in females structures. One copulating couple was present, with the male attached to the posteroventral part of the female with its anteroventral hooks and papillae. Several structures typical of arthropods and other pentastomids were identified. Because SEM allows only surfaces to be studied, the morphology and especially the sense organs of L. arctica

  5. Effect of Worm Predation on Changes in Waste Activated Sludge Properties.

    Science.gov (United States)

    Zhu, Xuefeng; Yuan, Wenyi; Wang, Zhiwei; Zhou, Mingyuan; Guan, Jie

    2016-05-01

    This study explored the effects of worm predation on changes in waste activated sludge properties. Results showed that the rate by which worm predation reduced mixed liquor volatile suspended solids (MLVSS) was approximately 23.7% ± 3.1%. Particle size distribution and extracellular polymeric substance (EPS) analyses indicated that the reduction of fine particles and EPS content in sludge predated by worms mainly increased dewaterability and reduced the ratio of MLVSS/mixed liquor suspended solids. Moreover, both mean particle size and protein/carbohydrate ratio increased. The results of three-dimensional excitation-emission matrix and gel filtration chromatogram analyses demonstrated the varied properties of soluble microbial products and EPS were attributed to the worms' selective predation of low molecular-weight organic matter, which facilitated the hydrolysis of macromolecular organic matter. PMID:27131302

  6. CHRONIC EFFECTS OF THE HERBICIDE DIURON ON FRESHWATER CLADOCERANS,AMPHIPODS,MIDGES,MINNOWS,WORMS, AND SNAILS

    Science.gov (United States)

    The chronic effects of the herbicide diuron on survival and reproduction of Daphnia pulex, and survival and growth of the amphipod Hyalella azteca, the midge Chironomus tentans, juvenile and embro/larval fathead minnows, Pimephales promelas, annelid worms, Lumbriculus variegatus,...

  7. Modeling and Stability Analysis of Worm Propagation in Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Liping Feng

    2015-01-01

    Full Text Available An improved SIRS model considering communication radius and distributed density of nodes is proposed. The proposed model captures both the spatial and temporal dynamics of worms spread process. Using differential dynamical theories, we investigate dynamics of worm propagation to time in wireless sensor networks (WSNs. Reproductive number which determines global dynamics of worm propagation in WSNs is obtained. Equilibriums and their stabilities are also found. If reproductive number is less than one, the infected fraction of the sensor nodes disappears and if the reproduction number is greater than one, the infected fraction asymptotically stabilizes at the endemic equilibrium. Based on the reproduction number, we discuss the threshold of worm propagation about communication radius and distributed density of nodes in WSNs. Finally, numerical simulations verify the correctness of theoretical analysis.

  8. Ascaris worm in the intercostal drainage bag: inadvertent intercostal tube insertion into jejunum: a case report

    OpenAIRE

    Mehta Harshad; Mistry Jitendra H; Mohite Prashant N; Patra BS

    2010-01-01

    Abstract Inadvertent insertion of the intercostal tube into abdomen is not rare. It can present by different ways. In the present case an Ascaris worm crept into the intercostal drainage bag to reveal the false passage of the tube.

  9. Toxicity of metals to a freshwater tubificid worm Tubifex tubifex (Muller)

    Energy Technology Data Exchange (ETDEWEB)

    Khangarot, B.S. (Industrial Toxicology Research Centre, Lucknow (India))

    1991-06-01

    Salts of various metals are being released in ever increasing amounts into the aquatic environment from mining operations, metal processing facilities, chemical industries and other similar sources. Although there has been considerable study of the acute and chronic toxicities of metals to freshwater fishes, crustaceans and snails, little information is available on the effects of metals to tubificid worms which are widely distributed in the aquatic environment. Tubificid worms are useful indicators of varying degrees of aquatic pollution. It is suggested that tubificid worms are an important element in the aquatic environment and therefore their use as a bioassay organism is logical one. The present study was undertaken to determine the acute toxicities of various metals to a fresh-water tubificid worm, Tubifex tubifex (Muller), which form an important link in aquatic food chain(s).

  10. The polychaete worm Nereis diversicolor increases mercury lability and methylation in intertidal mudflats.

    Science.gov (United States)

    Sizmur, Tom; Canário, João; Edmonds, Samuel; Godfrey, Adam; O'Driscoll, Nelson J

    2013-08-01

    The polychaete worm Nereis diversicolor engineers its environment by creating oxygenated burrows in anoxic intertidal sediments. The authors carried out a laboratory microcosm experiment to test the impact of polychaete burrowing and feeding activity on the lability and methylation of mercury in sediments from the Bay of Fundy, Canada. The concentration of labile inorganic mercury and methylmercury in burrow walls was elevated compared to worm-free sediments. Mucus secretions and organic detritus in worm burrows increased labile mercury concentrations. Worms decreased sulfide concentrations, which increased Hg bioavailability to sulfate-reducing bacteria and increased methylmercury concentrations in burrow linings. Because the walls of polychaete burrows have a greater interaction with organisms, and the overlying water, the concentrations of mercury and methylmercury they contain is more toxicologically relevant to the base of a coastal food web than bulk samples. The authors recommend that researchers examining Hg in marine environments account for sediment dwelling invertebrate activity to more fully assess mercury bioavailability. PMID:23633443

  11. Hydrolytic Degradation of Poly (ethylene oxide)-block-Polycaprolactone Worm Micelles

    OpenAIRE

    Geng, Yan; Discher, Dennis E.

    2005-01-01

    Spherical micelles and nanoparticles made with degradable polymers have been of great interest for therapeutic application, but degradation induced changes in a spherical morphology can be subtle and mechanism/kinetics appears poorly understood. Here, we report the first preparation of giant and flexible worm micelles self-assembled from degradable copolymer poly (ethylene oxide)-block-polycaprolactone. Such worm micelles spontaneously shorten to generate spherical micelles, triggered by poly...

  12. Dynamics of Infected Snails and Mated Schistosoma Worms within the Human Host

    Directory of Open Access Journals (Sweden)

    G. Besigye-Bafaki

    2005-01-01

    Full Text Available Male and female worms are independently distributed within a human host each with a Poisson probability distribution mass function. Mating takes place immediately when partners are available. It was found that the mated worm function is non-linear near the origin and becomes almost linear as the worms increase. They increase with increase in the worm load due to aggregation of worms. This also increases the infection of snails which are secondary hosts. On the analysis of the model, three equilibrium states were found, two of which were stable and one unstable. A stable endemic equilibrium within a community is very much undesirable. So the main objective of the model was to have the point O(0,0 as the only equilibrium point. This is a situation where there are no worms within the human host and the environment is free of infected snails. A critical point, above which the disease would be chronic and below which the disease would be eradicated, was found and analyzed. The parameters indicated that to achieve a disease free environment, the death rate of worms within the human host should be much greater than the cercariae that penetrate the human. Also the death rate of infected snails should be much higher than the contact rate between the miracidia and the snails. It was concluded that de-worming and killing of snails should be emphasized for disease control and educating the masses on the modes of disease transmission is quite necessary for prevention of the disease.

  13. Repeated evolution of limblessness and digging heads in worm lizards revealed by DNA from old bones.

    OpenAIRE

    Kearney, Maureen; Bryan L Stuart

    2004-01-01

    The evolutionary relationships of the burrowing amphisbaenians ('worm lizards') have long been controversial for several reasons: the rarity of museum specimens available for study, highly derived morphological conditions that can confound comparative studies and difficulty in obtaining tissues for molecular phylogenetic studies because of their secretive habits in the wild. We present a phylogenetic analysis of two nuclear genes obtained from both fresh tissues and museum specimens of worm l...

  14. Estimating the persistence length of a worm-like chain molecule from force-extension measurements.

    OpenAIRE

    Bouchiat, C.; Wang, M D; Allemand, J; Strick, T; Block, S M; Croquette, V.

    1999-01-01

    We describe a simple computation of the worm-like chain model and obtain the corresponding force-versus-extension curve. We propose an improvement to the Marko and Siggia interpolation formula of Bustamante et al (Science 1994, 265:1599-1600) that is useful for fitting experimental data. We apply it to the experimental elasticity curve of single DNA molecules. Finally, we present a tool to study the agreement between the worm-like chain model and experiments.

  15. Elimination of Schistosoma mansoni Adult Worms by Rhesus Macaques: Basis for a Therapeutic Vaccine?

    OpenAIRE

    Wilson, R. Alan; Langermans, Jan A. M.; van Dam, Govert J.; Vervenne, Richard A.; Hall, Stephanie L.; Borges, William C.; Dillon, Gary P.; Thomas, Alan W.; Patricia S Coulson

    2008-01-01

    Background Among animal models of schistosomiasis, the rhesus macaque is unique in that an infection establishes but egg excretion rapidly diminishes, potentially due to loss of adult worms from the portal system via shunts or death by immune attack. Principal Findings To investigate this, six rhesus macaques were exposed to Schistosoma mansoni cercariae and the infection monitored until portal perfusion at 18 weeks. Despite a wide variation in worm numbers recovered, fecal egg output and cir...

  16. Durability Characteristics Analysis of Plastic Worm Wheel with Glass Fiber Reinforced Polyamide

    OpenAIRE

    Tae-Il Seo; Jeong-Won Lee; Gun-Hee Kim

    2013-01-01

    Plastic worm wheel is widely used in the vehicle manufacturing field because it is favorable for weight lightening, vibration and noise reduction, as well as corrosion resistance. However, it is very difficult for general plastics to secure the mechanical properties that are required for vehicle gears. If the plastic resin is reinforced by glass fiber in the fabrication process of plastic worm wheel, it is possible to achieve the mechanical properties of metallic material levels. In this stud...

  17. Worm control practice against gastro-intestinal parasites in Norwegian sheep and goat flocks

    OpenAIRE

    Vatn Synnøve; Leine Nils; Gjerde Bjørn; Chartier Christophe; Domke Atle VM; Østerås Olav; Stuen Snorre

    2011-01-01

    Abstract Background Anthelmintic treatment is the most common way of controlling nematode infections in ruminants. However, several countries have reported anthelmintic resistance (AR), representing a limitation for sustainable small ruminant production. The knowledge regarding worm control management represents a baseline to develop a guideline for preventing AR. The aim of the present study was therefore to improve our knowledge about the worm control practices in small ruminant flocks in N...

  18. Expression of actin genes in the arrow worm Paraspadella gotoi (Chaetognatha)

    OpenAIRE

    Yasuda, Etsuko; Goto, Taichiro; Makabe, Kazuhiro W.; Satoh, Noriyuki

    1997-01-01

    Arrow worms (the phylum Chaetognatha), one of the major marine planktonic animals, exhibit features characteristic to both deuterostomes and protostomes, and their ancestry therefore remains unknown. As the first step to elucidate the molecular bases of arrow worm phylogeny, physiology and embryology, we isolated cDNA clones for three different actin genes (PgAct1, PgAct2 and PgAct3) from the benthic species Paraspadella gotoi, and examined their expression patterns in adults and juveniles. T...

  19. Red worm behavior (Eisenia spp. in vermicomposting systems of organic residues

    Directory of Open Access Journals (Sweden)

    Mamani-Mamani Gladys

    2012-08-01

    Full Text Available This work evaluates the behavior of the vermicomposting red worm (Eisenia spp. in two environments (greenhouse and unsheltered and with two solid organic substrates (cow manure=CM and kitchen waste=KW in the zone of Carmen Pampa, Nor Yungas Province, Department of La Paz – Bolivia, using a factorial design with two factors and three repetitions (ANOVA analysis. The largest number of cocoons was found in the greenhouse treatment, with 64 in CM and 41 in KW. Cocoon viability was also greatest in the greenhouse treatment, at 100% for CM and 96% for KW. Similarly, the greatest number of worms hatched from cocoons was in the greenhouse treatment, with 2 immature worms for CM and 3.5 for KW, and the greatest number of immature worms was registered in the greenhouse treatment with 123 individuals in CM and 16 in KW. The lowest mortality rate due to environment was in the greenhouse treatment, with 3.90% mortality with CM and 88.64% with KW. The greatest number of mature worms (with clitella was in the unsheltered treatment, with 15 in CM and 21 in KW. The greatest biomass of immature worms was found in the greenhouse treatment, with 1.41 g of worms for CM and 0.185 g for KW; however, the greatest biomass of mature worms was in the KW treatment, with 7.98 g for the greenhouse treatment and 6.93 g for the unsheltered treatment. The phytotoxicity from CM vermicompost in the two environments was lowest, exhibiting a 66.6% rate of germination, and the opposite was true for KW, which was the most toxic in both environments. Macronutrient content in vermicompost obtained was: nitrogen at 2.45% and 2.31%, phosphorus at 500 mg kg-1 and 220 mg kg-1 and potassium at 27.43 and 2.76 cmol(+ kg-1 of dry substrate in KW and CM respectively.

  20. Infestation of the clam Chione fluctifraga by the burrowing worm Polydora sp. nov. in laboratory conditions.

    Science.gov (United States)

    Tinoco-Orta, Gissel Dalila; Cáceres-Martínez, Jorge

    2003-07-01

    Burrowing worms that belong to Polydora spp. infest marine mollusks cultured worldwide, causing problems for production and marketing. The clam Chione fluctifraga is semi-cultured in Bahía Falsa, Baja California, NW Mexico, and some clams harbor burrowing worms. The present study was carried out to determine the identity of the worm species infesting the clam, the infesting process by cohabitation of infested and non-infested clams in aquaria with a variety of substrates (fine sand, gross sand, plastic bag used for clam culture, and aquarium without substrate) and turbulence conditions, and the occurrence of architomy phenomena in connection with infestation of the clam. The burrowing worm was considered as a nova species due to its singular limbate neurosetae and notosetae in the setiger 5, hooks in the setiger 6, eyes not present, and general pigmentation, among other characteristics. Infestation was similar in all substrates and turbulence conditions, but it was more abundant on clams previously infested than on those free of worms, showing a preferential settlement of worm infesting stages on pre-infested clams. Regeneration was observed in all segments of the worm: anterior (metastomium), medium, and posterior (prostomium); the complete regeneration time occurred in 40 days. This is the first record of architomy in a species of Polydora and this phenomenon could account for the increase of infestation intensity in pre-infested clams at the end of the study period. Infestation of clams by settling polichaete in the conditions studied, and the architomy process in this worm species, shows its great infesting capacity. PMID:12877826

  1. Uptake of plutonium from seawater and sediment by a marine polychaete worm

    International Nuclear Information System (INIS)

    The results of the uptake of plutonium 239 from sediment by a marine polychaete worm Nereis diversicolor is reported in the present paper. A comparison is made of the relative importance of two possible uptake pathways, sediment and seawater by which this worm may obtain its plutonium body-burden. Under the laboratory conditions used for the comparison of those two routes it would appear that Nereis obtained greater than 98% of its body activity from seawater. (auth.)

  2. Zinc and mechanical prowess in the jaws of Nereis, a marine worm

    OpenAIRE

    Lichtenegger, Helga C.; Schöberl, Thomas; Ruokolainen, Janne T.; Cross, Julie O.; Heald, Steve M.; Birkedal, Henrik; Waite, J. Herbert; Stucky, Galen D.

    2003-01-01

    Higher animals typically rely on calcification to harden certain tissues such as bones and teeth. Some notable exceptions can be found in invertebrates: The fangs, teeth, and mandibles of diverse arthropod species have been reported to contain high levels of zinc. Considerable quantities of zinc also occur in the jaws of the marine polychaete worm Nereis sp. High copper levels in the polychaete worm Glycera dibranchiata recently were attributed to a copper-based biomin...

  3. Round worm in common bile duct, a rare pathology: Review of 15 cases

    OpenAIRE

    Biswaranjan Nayak; Rashmi Rani Dash; Biranchi Narayan Mallik

    2014-01-01

    Round worm or Ascaris lumbricoides has a worldwide distribution but is more prevalent in the developing countries like India and other South Asian countries. In human beings, round worms are commonly found in the small intestine, particularly the jejunum. If the pathogen load is very high, it may migrate to other sites and manifest different symptoms. In this paper, we share our experience of biliary ascariasis with regards to its clinical presentation, diagnosis, conservative and surgical ma...

  4. Round worm in common bile duct, a rare pathology: Review of 15 cases

    Directory of Open Access Journals (Sweden)

    Biswaranjan Nayak

    2014-01-01

    Full Text Available Round worm or Ascaris lumbricoides has a worldwide distribution but is more prevalent in the developing countries like India and other South Asian countries. In human beings, round worms are commonly found in the small intestine, particularly the jejunum. If the pathogen load is very high, it may migrate to other sites and manifest different symptoms. In this paper, we share our experience of biliary ascariasis with regards to its clinical presentation, diagnosis, conservative and surgical management.

  5. Influence of ecologic factors on prevalence of meningeal worm (Parelaphostrongylus tenuis) infection in South Dakota, USA.

    Science.gov (United States)

    Jacques, Christopher N; Jenks, Jonathan A; Grovenburg, Troy W; Klaver, Robert W; Dubay, Shelli A

    2015-04-01

    The meningeal worm (Parelaphostrongylus tenuis) is a nematode parasite that commonly infects white-tailed deer (Odocoileus virginianus; WTD) throughout the deciduous forest biome and deciduous-coniferous ecotone of eastern and central North America; the species is not known to occur west of the grassland biome of central North America. We used county-specific prevalence data to evaluate potential effects of landscape and climatologic factors on the spatial distribution of meningeal worm infection in South Dakota, US. Probability of infection increased 4-fold between eastern and western South Dakota and 1.3-fold for each 1-cm increase in summer precipitation. Sixty-three percent of WTD had only a single worm in the cranium. Expansion of meningeal worm infection across western South Dakota may be inherently low due to the combined effects of arid climate and potential attributes of the Missouri River that limit regional movements by infected WTD. Use of landscape genetic analyses to identify potential relationships between landscape features and population genetic structure of infected deer and parasites may contribute to a greater understanding of regional heterogeneity in meningeal worm infection rates across South Dakota, particularly in counties adjacent to the Missouri River. Future research evaluating heterogeneity in prevalence and intensity of infection between fawn and yearling deer, and the potential role of yearling male deer as dispersal agents of meningeal worms across the Missouri River, also is warranted. PMID:25588013

  6. Functional characterization in Caenorhabditis elegans of transmembrane worm-human orthologs

    Directory of Open Access Journals (Sweden)

    Baillie David L

    2004-11-01

    Full Text Available Abstract Background The complete genome sequences for human and the nematode Caenorhabditis elegans offer an opportunity to learn more about human gene function through functional characterization of orthologs in the worm. Based on a previous genome-wide analysis of worm-human orthologous transmembrane proteins, we selected seventeen genes to explore experimentally in C. elegans. These genes were selected on the basis that they all have high confidence candidate human orthologs and that their function is unknown. We first analyzed their phylogeny, membrane topology and domain organization. Then gene functions were studied experimentally in the worm by using RNA interference and transcriptional gfp reporter gene fusions. Results The experiments gave functional insights for twelve of the genes studied. For example, C36B1.12, the worm ortholog of three presenilin-like genes, was almost exclusively expressed in head neurons, suggesting an ancient conserved role important to neuronal function. We propose a new transmembrane topology for the presenilin-like protein family. sft-4, the worm ortholog of surfeit locus gene Surf-4, proved to be an essential gene required for development during the larval stages of the worm. R155.1, whose human ortholog is entirely uncharacterized, was implicated in body size control and other developmental processes. Conclusions By combining bioinformatics and C. elegans experiments on orthologs, we provide functional insights on twelve previously uncharacterized human genes.

  7. Comparison of influences of sediments and sea water on accumulation of radionuclides by worms

    International Nuclear Information System (INIS)

    The accumulation and excretion of radionuclides by marine polychaete worms (Nereis japonica) were examined to learn the influence of contaminated sediments on the contamination of marine organisms. The concentration factors of 60Co, 95Zr-95Nb, 106Ru-106Rh and 137Cs for unfed worms were 6, 4, 6 and 6 respectively, and they were similar to the concentration factors for unfed worms. The biological half lives of 60Co, 95Zr-95Nb and 106Ru-106Rh for fed worms were similar to each other (37, 32 and 35 days, respectively) except that of 137Cs (6 days), and all of them were a little shorter than those for unfed worms. The transfer ratios of radionuclides from sediments to worms were 5 per cent for 60Co, 0.9 for 95Zr-95Nb, 0.6 for 106Ru-106Rh and 17.9 for 137Cs in cpm/g in regard to initial activity in sediments. These figures were compared with the concentration factors to estimate the influence of sediments on the contamination of marine organisms. The obtained figures, which we call the biological factor of the sediments, were 120, 440, 1000 and 30 for 60Co, 95Zr-95Nb, 106Ru-106Rh and 137Cs, respectively. (auth.)

  8. An inconvenient truth: global worming and anthelmintic resistance.

    Science.gov (United States)

    Kaplan, Ray M; Vidyashankar, Anand N

    2012-05-01

    Over the past 10-15 years, we have witnessed a rapid increase in both the prevalence and magnitude of anthelmintic resistance, and this increase appears to be a worldwide phenomenon. Reports of anthelmintic resistance to multiple drugs in individual parasite species, and in multiple parasite species across virtually all livestock hosts, are increasingly common. In addition, since the introduction of ivermectin in 1981, no novel anthelmintic classes were developed and introduced for use in livestock until recently with the launch of monepantel in New Zealand. Thus, livestock producers are often left with few options for effective treatment against many important parasite species. While new anthelmintic classes with novel mechanisms of action could potentially solve this problem, new drugs are extremely expensive to develop, and can be expected to be more expensive than older drugs. Thus, it seems clear that the "Global Worming" approach that has taken hold over the past 40-50 years must change, and livestock producers must develop a new vision for parasite control and sustainability of production. Furthermore, parasitologists must improve methods for study design and data analysis that are used for diagnosing anthelmintic resistance, especially for the fecal egg count reduction test (FECRT). Currently, standards for diagnosis of anthelmintic resistance using FECRT exist only for sheep. Lack of standards in horses and cattle and arbitrarily defined cutoffs for defining resistance, combined with inadequate analysis of the data, mean that errors in assigning resistance status are common. Similarly, the lack of standards makes it difficult to compare data among different studies. This problem needs to be addressed, because as new drugs are introduced now and in the future, the lack of alternative treatments will make early and accurate diagnosis of anthelmintic resistance increasingly important. PMID:22154968

  9. Perceptions of a literate community regarding causation, presentation and treatment practices of intestinal worms among children

    International Nuclear Information System (INIS)

    To find out the perceived common causes of intestinal worms, their presentations and treatment options taken by the respondents, among children. A total of 2000 families responded to a self-administered questionnaire that was designed to obtain the study objectives. A single adult individual from each family was asked to respond to the questionnaire. Families having health care workers or health professionals were excluded. Medical students were properly trained to ensure competence in collecting a reliable data. The majority of the total respondents were females (66.3%) and were between 15-25 years of age (mean age = 25.4 years) with 100% literacy rate. A noticeable number of respondents (31%) revealed that overeating of sugar causes intestinal worms and that they mainly presented as altered eating habits / appetite (51.8%), abdominal pain (40.8%) and generalized weakness (26.3%). Regarding perceptions of drug treatment, nearly 2/3 of the respondents felt that the de-worming agent should be given to suspected child only (p < 0.001), whereas 65% of the participants expected to observe worms after de-worming treatment (p < 0.001). Contrary to the common use of self-medication in most other illnesses, self-treatment of worms on suspicion was declared by only 21.5% of the respondents (p < 0.0001). This study confirms that misconceptions about intestinal worms in children were prevalent within the community. In addition to the issue of environmental sanitation, removal of the mistaken beliefs is a prerequisite for an effective and long-lasting parasitic control among children. (author)

  10. Mathematical Model and Geometrical Model of Double Pitch ZN-type Worm Gear Set Based on Generation Mechanism

    Institute of Scientific and Technical Information of China (English)

    SHU Linsen; CAO Huajun; LI Xianchong; ZHANG Chenglong; LI Yuxia

    2015-01-01

    The current researches on the tooth surface mathematical equations and the theory of gearing malnly pay attention to the ordinary type worm gear set (e.g., ZN, ZA, or ZK). The research of forming mechanism and three-dimensional modeling method for the double pitch worm gear set is not enough. So there are some difficulties in mathematical model deducing and geometry modeling of double pitch ZN-type worm gear set based on generation mechanism. In order to establish the mathematical model and the precise geometric model of double pitch ZN-type worm gear set, the structural characteristics and generation mechanism of the double pitch ZN-type worm gear set are investigated. Mathematical model of the ZN-type worm gear set is derived based on its generation mechanism and the theory of gearing. According to the mathematical model of the worm gear set which has been developed, a geometry modeling method of the double pitch ZN-type worm and worm gear is presented. Furthermore, a geometrical precision calculate method is proposed to evaluate the geometrical quality of the double pitch worm gear set. As a result, the maximum error is less than 6´10–4 mm in magnitude, thus the model of the double pitch ZN-type worm gear set is avallable to meet the requirements of finite element analysis and engineering application. The derived mathematical model and the proposed geometrical modeling method are helpful to guiding the design, manufacture and contact analysis of the worm gear set.

  11. Changes in aliphatic hydrocarbon tracer composition during the digestive process of the marine worm Nereis virens. Preliminary results

    OpenAIRE

    Gilbert, Franck; Stora, Georges; Desrosiers, Gaston; Gagne, Jean-Pierre; Deflandre, Bruno; Bertrand, Jean-Claude

    1998-01-01

    In the laboratory, marine worms were fed with a mixture of algae and several aliphatic hydrocarbons for 15 days. By comparing hydrocarbons in food and in faeces, it appeared that the worm's digestive process led to changes in the distribution of the n-alkanes mixture. These changes were different from those only due to physical processes in the experimental conditions, indicating that marine worm feeding could substantially affect the fate of hydrocarbons in the sedimentary marine ecosystem.

  12. Phagocytes: A Holistic Defense and Protection Against Active P2P Worms

    CERN Document Server

    Chen, Ruichuan; Crowcroft, Jon; Tang, Liyong; Chen, Zhong

    2011-01-01

    Active Peer-to-Peer (P2P) worms present serious threats to the global Internet by exploiting popular P2P applications to perform rapid topological self-propagation. Active P2P worms pose more deadly threats than normal scanning worms because they do not exhibit easily detectable anomalies, thus many existing defenses are no longer effective. We propose an immunity system with Phagocytes --- a small subset of elected P2P hosts that are immune with high probability and specialized in finding and "eating" worms in the P2P overlay. The Phagocytes will monitor their managed P2P hosts' connection patterns and traffic volume in an attempt to detect active P2P worm attacks. Once detected, local isolation, alert propagation and software patching will take place for containment. The Phagocytes further provide the access control and filtering mechanisms for communication establishment between the internal P2P overlay and the external hosts. We design a novel adaptive and interaction-based computational puzzle scheme at ...

  13. WormGender - Open-Source Software for Automatic Caenorhabditis elegans Sex Ratio Measurement.

    Directory of Open Access Journals (Sweden)

    Marta K Labocha

    Full Text Available Fast and quantitative analysis of animal phenotypes is one of the major challenges of current biology. Here we report the WormGender open-source software, which is designed for accurate quantification of sex ratio in Caenorhabditis elegans. The software functions include, i automatic recognition and counting of adult hermaphrodites and males, ii a manual inspection feature that enables manual correction of errors, and iii flexibility to use new training images to optimize the software for different imaging conditions. We evaluated the performance of our software by comparing manual and automated assessment of sex ratio. Our data showed that the WormGender software provided overall accurate sex ratio measurements. We further demonstrated the usage of WormGender by quantifying the high incidence of male (him phenotype in 27 mutant strains. Mutants of nine genes (brc-1, C30G12.6, cep-1, coh-3, him-3, him-5, him-8, skr-1, unc-86 showed significant him phenotype. The WormGender is written in Java and can be installed and run on both Windows and Mac platforms. The source code is freely available together with a user manual and sample data at http://www.QuantWorm.org/. The source code and sample data are also available at http://dx.doi.org/10.6084/m9.figshare.1541248.

  14. In Vitro Cestocidal Activity of Thymol on Mesocestoides corti Tetrathyridia and Adult Worms

    Directory of Open Access Journals (Sweden)

    M. Maggiore

    2014-01-01

    Full Text Available Nothing is known about the possible effect of thymol or other compounds of essential oils against the adult worms of cestodes. The aim of the present work was to determine in vitro cestodicidal activity of thymol against Mesocestoides corti adult worms. Moreover, the in vitro effect on tetrathyridia was also demonstrated. Tetrathyridia exposed to different concentrations of thymol showed a concentration and time-dependent effect. At lower concentrations, the main change observed was mainly in morphology, with larvae exhibiting an elongation of the body. When tetrathyridia were exposed to higher concentrations, increased surface alterations and damage were detected. The body appeared elongated and flattened, and a complete loss of morphology and microtriches was observed. Thymol was able to kill M. corti tetrathyridia, since following inoculation of treated parasites in mice no parasites could be recovered. The effect on M. corti adult worms was dose and time-dependent. Changes in motility coincide with the tissue damage were observed at the structural and ultrastructural level. Thymol caused severe damages to both developmental stages analyzed. Damages were more significant in fully segmented worms. The data reported in this paper demonstrate a clear in vitro effect of thymol against M. corti tetrathyridia and adult worms.

  15. Adult filarial worm from the breast aspirate of a young man.

    Science.gov (United States)

    Fernandes, Hilda; Thomas, Beena Mary; Putran, Indira

    2016-06-01

    Microfilariae and adult filarial worm have been incidentally detected in fine needle aspirates of various lesions in clinically unsuspected cases. Here we report a male patient who presented with a tender breast nodule and single enlarged lymph node. Fine Needle Aspiration (FNA) yielded 1 ml of yellow coloured fluid and single thread like worm measuring 6 × 0.2 cm. A diagnosis of breast abscess with a worm morphologically consistent with filariasis was offered. A follow up visit after 2 months showed regression of the breast lesion and the lymph node. Filariasis of the breast is an uncommon condition and can cause a diagnostic dilemma at times. FNA cytology appears to be a more convenient and effective diagnostic tool in patients with mass lesions. Demonstration and identification of the parasite in smears helps in avoiding surgical excision and early institution of prompt therapy especially in young patients. PMID:27413335

  16. Expression pattern of the Brachyury gene in the arrow worm paraspadella gotoi (chaetognatha).

    Science.gov (United States)

    Takada, Norio; Goto, Taichiro; Satoh, Nori

    2002-03-01

    Arrow worms (the phylum Chaetognatha), which are among the major marine planktonic animals, are direct developers and exhibit features characteristic of both deuterostomes and protostomes. In particular, the embryonic development of arrow worms appears to be of the deuterostome type. Brachyury functions critically in the formation of the notochord in chordates, whereas the gene is expressed in both the blastopore and stomodeum invagination regions in embryos of hemichordates and echinoderms. Here we analyzed the expression of Brachyury (Pg-Bra) in the arrow worm Paraspadella gotoi and showed that Pg-Bra is expressed in the blastopore region and the stomodeum region in the embryo and then around the mouth opening region at the time of hatching. The expression of Pg-Bra in the embryo resembles that of Brachyury in embryos of hemichordates and echinoderms, whereas that in the mouth opening region in the hatchling appears to be novel. PMID:11892013

  17. Ectopic Human Fasciola hepatica Infection by an Adult Worm in the Mesocolon.

    Science.gov (United States)

    Kim, Ah Jin; Choi, Chang Hwan; Choi, Sun Keun; Shin, Yong Woon; Park, Yun-Kyu; Kim, Lucia; Choi, Suk Jin; Han, Jee Young; Kim, Joon Mee; Chu, Young Chae; Park, In Suh

    2015-12-01

    We report here an ectopic case of Fasciola hepatica infection confirmed by recovery of an adult worm in the mesocolon. A 56-year-old female was admitted to our hospital with discomfort and pain in the left lower quadrant of the abdomen. Abdominal CT showed 3 abscesses in the left upper quadrant, mesentery, and pelvic cavity. On surgical exploration, abscess pockets were found in the mesocolon of the sigmoid colon and transverse colon. A leaf-like worm found in the abscess pocket of the mesocolon of the left colon was diagnosed as an adult fluke of F. hepatica. Histologically, numerous eggs of F. hepatica were noted with acute and chronic granulomatous inflammations in the subserosa and pericolic adipose tissues. Conclusively, a rare case of ectopic fascioliasis has been confirmed in this study by the adult worm recovery of F. hepatica in the mesocolon. PMID:26797440

  18. Evaluation of existing EPRI and INEL test data to determine the worm to worm gear coefficient of friction in Limitorque actuators

    International Nuclear Information System (INIS)

    About the last sizing parameter for motor operated valves which has not been determined by utility or NRC sponsored testing is actuator efficiency. A by-product of EPRI testing for valve factors is the measurement of the actuator efficiencies. Motor sizing in this testing provides efficiency testing for motors running near synchronous speed. INEL testing, sponsored by the NRC, for stem factors and rate of loading provides complimentary data for motors loaded down to zero speed. This paper analyzes the data from these two test programs to determine the coefficient of friction for the worm to worm gear interface. This allowed the development of an algorithm for determining the efficiency of actuators which have not been tested. This paper compares the results of this algorithm to the test data to provide a measure of the accuracy of this method for calculating actuator efficiency

  19. Evaluation of existing EPRI and INEL test data to determine the worm to worm gear coefficient of friction in Limitorque actuators

    Energy Technology Data Exchange (ETDEWEB)

    Garza, I.A.

    1996-12-01

    About the last sizing parameter for motor operated valves which has not been determined by utility or NRC sponsored testing is actuator efficiency. A by-product of EPRI testing for valve factors is the measurement of the actuator efficiencies. Motor sizing in this testing provides efficiency testing for motors running near synchronous speed. INEL testing, sponsored by the NRC, for stem factors and rate of loading provides complimentary data for motors loaded down to zero speed. This paper analyzes the data from these two test programs to determine the coefficient of friction for the worm to worm gear interface. This allowed the development of an algorithm for determining the efficiency of actuators which have not been tested. This paper compares the results of this algorithm to the test data to provide a measure of the accuracy of this method for calculating actuator efficiency.

  20. In vitro antifilarial effects of three plant species against adult worms of subperiodic Brugia malayi.

    Science.gov (United States)

    Zaridah, M Z; Idid, S Z; Omar, A W; Khozirah, S

    2001-11-01

    Five aqueous extracts from three plant species, i.e., dried husks (HX), dried seeds (SX) and dried leaves (LX) of Xylocarpus granatum (Meliaceae), dried stems (ST) of Tinospora crispa (Menispermaceae) and dried leaves (LA) of Andrographis paniculata (Acanthaceae) were tested in vitro against adult worms of subperiodic Brugia malayi. The relative movability (RM) value of the adult worms over the 24-h observation period was used as a measure of the antifilarial activity of the aqueous extracts. SX extract of X. granatum demonstrated the strongest activity, followed by the LA extract of A. paniculata, ST extract of T. crispa, HX extract and LX extract of X. granatum. PMID:11585692

  1. Aqueous worm gels can be reconstituted from freeze-dried diblock copolymer powder

    OpenAIRE

    Kocik, M. K.; Mykhaylyk, O. O.; Armes, S. P.

    2014-01-01

    Worm-like diblock copolymer nanoparticles comprising poly(glycerol monomethacrylate) (PGMA) as a stabilizer block and poly(2-hydroxypropyl methacrylate) (PHPMA) as a core-forming block were readily synthesized at 10% w/w solids via aqueous dispersion polymerization at 70 °C using Reversible Addition-Fragmentation chain Transfer (RAFT) chemistry. On cooling to 20 °C, soft transparent free-standing gels are formed due to multiple inter-worm interactions. These aqueous PGMA-PHPMA diblock copolym...

  2. Distribution, abundance and trail characteristics of acorn worms at Australian continental margins

    Science.gov (United States)

    Anderson, T. J.; Przeslawski, R.; Tran, M.

    2011-04-01

    Acorn worms (Enteropneusta), which were previously thought to be a missing link in understanding the evolution of chordates, are an unusual and potentially important component of many deep-sea benthic environments, particularly for nutrient cycling. Very little is known about their distribution, abundance, or behaviour in deep-sea environments around the world, and almost nothing is known about their distribution within Australian waters. In this study, we take advantage of two large-scale deep-sea mapping surveys along the eastern (northern Lord Howe Rise) and western continental margins of Australia to quantify the distribution, abundance and trail-forming behaviour of this highly unusual taxon. This is the first study to quantify the abundance and trail behaviour of acorn worms within Australian waters and provides the first evidence of strong depth-related distributions. Acorn worm densities and trail activity were concentrated between transect-averaged depths of 1600 and 3000 m in both eastern and western continental margins. The shallow limit of their depth distribution was 1600 m. The deeper limit was less well-defined, as individuals were found in small numbers below 3000 down to 4225 m. This distributional pattern may reflect a preference for these depths, possibly due to higher availability of nutrients, rather than a physiological constraint to greater depths. Sediment characteristics alone were poor predictors of acorn worm densities and trail activity. High densities of acorn worms and trails were associated with sandy-mud sediments, but similar sediment characteristics in either shallower or deeper areas did not support similar densities of acorn worms or trails. Trail shapes varied between eastern and western margins, with proportionally more meandering trails recorded in the east, while spiral and meandering trails were both common in the west. Trail shape varied by depth, with spiral-shaped trails dominant in areas of high acorn worm densities

  3. SQL/JavaScript Hybrid Worms As Two-stage Quines

    CERN Document Server

    Orlicki, José I

    2009-01-01

    Delving into present trends and anticipating future malware trends, a hybrid, SQL on the server-side, JavaScript on the client-side, self-replicating worm based on two-stage quines was designed and implemented on an ad-hoc scenario instantiating a very common software pattern. The proof of concept code combines techniques seen in the wild, in the form of SQL injections leading to cross-site scripting JavaScript inclusion, and seen in the laboratory, in the form of SQL quines propa- gated via RFIDs, resulting in a hybrid code injection. General features of hybrid worms are also discussed.

  4. Morphometric study of Schistosoma mansoni adult worms recovered from undernourished infected mice

    Directory of Open Access Journals (Sweden)

    Sheilla A Oliveira

    2003-07-01

    Full Text Available Some unfavourable effects of malnutrition of the host on Schistosoma mansoni worm biology and structure have been reported based upon brigthfield microscopy. This paper aims to study by morphometric techniques, some morphological parameters in male and female adult worms recovered from undernourished albino mice in comparison with parasites recovered from well-fed infected mice. Undernourished animals were fed a multideficient and essentially low protein diet (RBD diet and compared to well-fed control mice fed with the commercial diet NUVILAB. Seventy-five days post-infection with 80 cercarie (BL strain animals were sacrificed. All adult worms were fixed in 10% formalin and stained with carmine chloride. One hundred male and 60 female specimens from each group (undernourished and control were examined using an image system analysis Leica Quantimet 500C and the Sigma Scan Measurement System. The following morphometrical parameters were studied: body length and width, oral and ventral suckers, number and area of testicular lobes, length and width of ovary and uterine egg. For statistical analysis, the Student's t test for unpaired samples was applied. Significant differences (p < 0.05 were detected in body length and width, in parameters of suckers, uterine egg width, ovary length and area of testicular lobes, with lower values for specimens from undernourished mice. The nutritional status of the host has negative influence on S. mansoni adult worms, probably through unavailability of essential nutrients to the parasites.

  5. A new method of DNA extraction from the ethanol-fixed parasitic worms

    OpenAIRE

    Tkach,Vasyl; Pawlowski, Jan Wojciech

    1999-01-01

    A protocol of the new method of DNA extraction from the ethanol fixed parasitic worms is described. The method is based on the use of the guanidine thiocyanate extraction buffer after evaporation of the ethanol from the tissues of drying. The method has been successfully used on several groups of parasitic Plathyhelminthes and provided higher DNA yield than a conventional phenol-chloroform extraction.

  6. The uptake in vitro of dyes, monosaccharides and amino acids by the filarial worm Brugia pahangi

    International Nuclear Information System (INIS)

    The uptake of D-glucose and L-leucine by B. pahangi was demonstrated using autoradiographic and scintillation counting techniques and incorporation into worm tissues was detected. Glucose was found to be readily incorporated in the apical, glycogen-rich areas of the myocytes of worms of all ages studied and in the uterine epithelium of the adult female. In contrast, a lower incorporation of D-glucose was found in the eggs, embryos and vas deferens and especially in the gut. The incorporation of L-leucine occurred throughout the tissue of the worms during a 30 min incubation. Labelling was also located over the surface of the cuticle of the worms, when incubated for a period of 15 to 60 min in L-[3H]leucine. Scintillation counting techniques demonstrated that there was no uptake of 14C-labelled L-glucose or sucrose by B. pahangi. The data presented on the uptake in vitro of nutrients or other compounds by infective larvae and adult stages of B. pahangi did not demonstrate an intestinal route of uptake but indicated that the transcuticular route of uptake may be employed. (author)

  7. From early lessons to new frontiers: the worm as a treasure trove of small RNA biology.

    Science.gov (United States)

    Youngman, Elaine M; Claycomb, Julie M

    2014-01-01

    In the past 20 years, the tiny soil nematode Caenorhabditis elegans has provided critical insights into our understanding of the breadth of small RNA-mediated gene regulatory activities. The first microRNA was identified in C. elegans in 1993, and the understanding that dsRNA was the driving force behind RNA-mediated gene silencing came from experiments performed in C. elegans in 1998. Likewise, early genetic screens in C. elegans for factors involved in RNA interference pointed to conserved mechanisms for small RNA-mediated gene silencing pathways, placing the worm squarely among the founding fathers of a now extensive field of molecular biology. Today, the worm continues to be at the forefront of ground-breaking insight into small RNA-mediated biology. Recent studies have revealed with increasing mechanistic clarity that C. elegans possesses an extensive nuclear small RNA regulatory network that encompasses not only gene silencing but also gene activating roles. Further, a portrait is emerging whereby small RNA pathways play key roles in integrating responses to environmental stimuli and transmitting epigenetic information about such responses from one generation to the next. Here we discuss endogenous small RNA pathways in C. elegans and the insight worm biology has provided into the mechanisms employed by these pathways. We touch on the increasingly spectacular diversity of small RNA biogenesis and function, and discuss the relevance of lessons learned in the worm for human biology. PMID:25505902

  8. From early lessons to new frontiers: The worm as a treasure trove of small RNA biology

    Directory of Open Access Journals (Sweden)

    Elaine M. Youngman

    2014-11-01

    Full Text Available In the past twenty years, the tiny soil nematode C. elegans has provided critical insights into our understanding of the breadth of small RNA-mediated gene regulatory activities. The first microRNA was identified in C. elegans in 1993, and the understanding that dsRNA was the driving force behind RNA-mediated gene silencing came from experiments performed in C. elegans in 1998. Likewise, early genetic screens in C. elegans for factors involved in RNAi pointed to conserved mechanisms for small RNA-mediated gene silencing pathways, placing the worm squarely among the founding fathers of a now extensive field of molecular biology. Today, the worm continues to be at the forefront of ground-breaking insight into small RNA-mediated biology. Recent studies have revealed with increasing mechanistic clarity that C. elegans possesses an extensive nuclear small RNA regulatory network that encompasses not only gene silencing but also gene activating roles. Further, a portrait is emerging whereby small RNA pathways play key roles in integrating responses to environmental stimuli and transmitting epigenetic information about such responses from one generation to the next. Here we discuss endogenous small RNA pathways in C. elegans and the insight worm biology has provided into the mechanisms employed by these pathways. We touch on the increasingly spectacular diversity of small RNA biogenesis and function, and discuss the relevance of lessons learned in the worm for human biology.

  9. Ascaris worm in the intercostal drainage bag: inadvertent intercostal tube insertion into jejunum: a case report

    Directory of Open Access Journals (Sweden)

    Mehta Harshad

    2010-12-01

    Full Text Available Abstract Inadvertent insertion of the intercostal tube into abdomen is not rare. It can present by different ways. In the present case an Ascaris worm crept into the intercostal drainage bag to reveal the false passage of the tube.

  10. In-vitro antihelmintic effects of two Kenyan plant extracts against Heamonchus contortus adult worms

    Directory of Open Access Journals (Sweden)

    Patrick Gachoki Kareru

    2012-10-01

    Full Text Available This study was on evidence based information that Entada leptostachya Harms and Rapanea rhododendroides (Gil Mez were used by the herbalists in Mbeere County, Kenya, for the treatment of gastrointestinal worms. The plants’ aqueous and solvent extracts were tested for their in-vitro antihelmintic activity against Haemonchus contortus adult worms. Of the eight plant extracts investigated, four extracts exhibited adult worm mortality greater than 50% while the other four afforded mortality ranging between 60-77%. E. leptostachya methanol extract was the most active (77%. Albendazole was used as a positive control drug while Goodwin’s physiological solution was used as negative control. Methanol extracts for both plants exhibited the highest anthelmintic activity at the test concentrations of 25mg/ml. Although R. rhododendroides was ranked third in general usage by the herbalists, E. leptostachya was solely used for the treatment of intestinal worms. The present results demonstrated that E. leptostachya and R. rhododendroides plant extracts had antihelmintic agents, and justified their traditional use as alternative drugs for the treatment of heamonchosis in ruminants.

  11. Correlates of Anaemia and Worm Infestation among Rural Pregnant Women: A Cross Sectional Study from Bengal

    Directory of Open Access Journals (Sweden)

    Sinjita Dutta, Sita Chatterjee, Debasish Sinha, Bobby Pal, Mausumi Basu, Aparajita Dasgupta

    2013-01-01

    Objectives: To find out the preva-lence of worm infestation and anaemia among pregnant women along with their socio-demographic characteristics, dietary habits and state of personal hygiene and elicit the association, if any, with anemia and worm infestation Materials and methods: A cross-sectional study was carried out among pregnant mothers attending the antenatal clinic at Nasibpur Union Health Center. All antenatal mothers who came for antenatal checkup for the first time to the health centre on two prefixed days of the week during the study period were interviewed. The reports of their stool and haemoglobin examination were followed up. Results: 82% of the pregnant women were suffering from anemia.25% of the study population had worm infestation. Age at marriage, green leafy vegetable, fruit and flesh food intake of at least 4 days a week, use of lemon with food most of the time, avoiding the practice of eating last in the family, handwashing with soap and water before eating and use of footwear outside the house were statically significant with hemoglobin concentration. Only religion and handwashing practice with soap and water before eating had statistically significant association with worm infestation. Conclusion: The study showed that certain protective factors like diet and personal hygiene if addressed at the time of antenatal checkup can reduce the number of cases of anemia significantly.

  12. Metallothioneins induction and antioxidative response in aquatic worms Tubifex tubifex (Oligochaeta, Tubificidae) exposed to copper.

    Science.gov (United States)

    Mosleh, Yahia Y; Paris-Palacios, Séverine; Biagianti-Risbourg, Sylvie

    2006-06-01

    Metallothioneins (MTs), are low molecular weight proteins, mainly implicated in metal ion detoxification. Increase in MT contents is considered as a specific biomarker of metal exposure. Recently it has been demonstrated that MTs participate in several cellular functions such as regulation of growth, and antioxidative defences. Tubifex tubifex were exposed to different copper concentrations (50, 100, and 200 microgl(-1)) for 7 and 15 days. MT levels in exposed worms increased significantly (p<0.05) after 7 and 15 days of exposure to different concentrations of copper (maximum +208% for 100 microgl(-1) after 7 days of exposure). Also important perturbation in metal-metallothionein content occurred, along with an increase in total soluble protein content in all treated worms after 7 and 15 days (max. +88.49%). Catalase activities (CAT) in Cu treated-worms were significantly increased, and demonstrated a development of antioxidative defenses. Additionally a reduction of gulathione-S-transferase (GST) was observed in all treated worms after 7 days of exposure to Cu (max. -44.42%). The high induction of MTs observed during T. tubifex exposure to Cu make them potentially useful biomarkers to monitor metal pollution. PMID:16330073

  13. Toxicity of metallic oxides nanoparticle suspensions to a freshwater sludge worm Tubifex tubifex Müller.

    Science.gov (United States)

    Verma, Surabhi; Das, Sangita; Khangarot, B S

    2011-02-01

    Toxic effects of selected metallic oxides nanoparticles were studied using the short-term static bioassays. Nanoparticles were more toxic than comparable bulk metallic oxides. Freshwater sludge worm Tubifex tubifex can be used as suitable test model for nanoecotoxicological studies in future studies. PMID:21485877

  14. Sediment-worm interaction: transfer of 65Zn from marine silt by the polychaete, Nereis diversicolor

    International Nuclear Information System (INIS)

    Marine polychaete worms (Nereis diversicolor) accumulated 65Zn sorbed to silty marine sediment for 5 days and were then transferred to nonradioactive sediment in the laboratory and in the sea. The mean biological half-life (T/sub B//2/) for the laboratory worms did not differ greatly from that for worms in the sea. Worms living in small flowing seawater systems containing 16 cm3 of sediment accumulated 65Zn added to each system in the form of radioactive organic detritus. Higher percentage uptake of 65Zn was from radioactive detritus particles 0.2 to 2 mm in diameter resting on the sediment surface or mixed with sediment than from finely-ground (65Zn coprecipitated from fresh water with Fe(OH)3 was accumulated by N. diversicolor when the precipitate was on the sediment surface than when the precipitate was well mixed with the sediment. These experimental results indicate that benthic organisms may take up limited amounts of heavy metals associated with bottom sediments and recycle them to benthic and pelagic food webs

  15. WormSizer: high-throughput analysis of nematode size and shape.

    Directory of Open Access Journals (Sweden)

    Brad T Moore

    Full Text Available The fundamental phenotypes of growth rate, size and morphology are the result of complex interactions between genotype and environment. We developed a high-throughput software application, WormSizer, which computes size and shape of nematodes from brightfield images. Existing methods for estimating volume either coarsely model the nematode as a cylinder or assume the worm shape or opacity is invariant. Our estimate is more robust to changes in morphology or optical density as it only assumes radial symmetry. This open source software is written as a plugin for the well-known image-processing framework Fiji/ImageJ. It may therefore be extended easily. We evaluated the technical performance of this framework, and we used it to analyze growth and shape of several canonical Caenorhabditis elegans mutants in a developmental time series. We confirm quantitatively that a Dumpy (Dpy mutant is short and fat and that a Long (Lon mutant is long and thin. We show that daf-2 insulin-like receptor mutants are larger than wild-type upon hatching but grow slow, and WormSizer can distinguish dauer larvae from normal larvae. We also show that a Small (Sma mutant is actually smaller than wild-type at all stages of larval development. WormSizer works with Uncoordinated (Unc and Roller (Rol mutants as well, indicating that it can be used with mutants despite behavioral phenotypes. We used our complete data set to perform a power analysis, giving users a sense of how many images are needed to detect different effect sizes. Our analysis confirms and extends on existing phenotypic characterization of well-characterized mutants, demonstrating the utility and robustness of WormSizer.

  16. Moxidectin causes adult worm mortality of human lymphatic filarial parasite Brugia malayi in rodent models.

    Science.gov (United States)

    Verma, Meenakshi; Pathak, Manisha; Shahab, Mohd; Singh, Kavita; Mitra, Kalyan; Misra-Bhattacharya, Shailja

    2014-12-01

    Moxidectin is a macrocyclic lactone belonging to milbemycin family closely related to ivermectin and is currently progressing towards Phase III clinical trial against human infection with the filaria Onchocerca volvulus (Leuckart, 1894). There is a single report on the microfilaricidal and embryostatic activity of moxidectin in case of the human lymphatic filarial parasite Brugia malayi (Brug, 1927) in Mastomys coucha (Smith) but without any adulticidal action. In the present study, the in vitro and in vivo antifilarial efficacy of moxidectin was evaluated on, B. malayi. In vitro moxidectin showed 100% reduction in adult female worm motility at 0.6 μM concentration within 7 days with 68% inhibition in the reduction of MTT (3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide dye) (which is used to detect viability of worms). A 50% inhibitory concentration (IC50) of moxidectin for adult female parasite was 0.242 μM, for male worm 0.186 μM and for microfilaria IC50 was 0.813 μM. In adult B. malayi-transplanted primary screening model (Meriones unguiculatus Milne-Edwards), moxidectin at a single optimal dose of 20 mg/kg by oral and subcutaneous route was found effective on both adult parasites and microfilariae. In secondary screening (M coucha, subcutaneously inoculated with infective larvae), moxidectin at the same dose by subcutaneous route brought about death of 49% of adult worms besides causing sterilisation in 54% of the recovered live female worms. The treated animals exhibited a continuous and sustained reduction in peripheral blood microfilaraemia throughout the observation period of 90 days. The mechanism of action of moxidectin is suggested to be similar to avermectins. The in silico studies were also designed to explore the interaction of moxidectin with glutamate-gated chloride channels of B. malayi. The docking results revealed a close interaction of moxidectin with various GluCl ligand sites of B. malayi. PMID:25651699

  17. PCB concentrations in intertidal sipunculan (Phylum Sipuncula) marine worms from the Pacific coast of Costa Rica

    International Nuclear Information System (INIS)

    Specimens of the sipunculans Phascolosoma perlucens, Antillesoma antillarum, and Sipunculus nudus, were collected for PCB analysis in three coastal embayments of the Pacific coast of Costa Rica in October 2005. After collection the worms were kept in cool sea water and transferred to the laboratory for freeze drying. Half of the specimens of S. nudus were purified in filtered sea water for 72 h before freeze drying. The whole worm sample was ground, using a mortar and pestle prior to being extracted with dichloromethane solvent. The extract was cleaned using a florisil column and analyzed using a 6890 Hewlett-Packard gas chromatograph equipped with a mass selective detector. Recovery efficiencies averaged between 72 and 80 %. Data are not corrected for blank or recovery efficiencies. Concentration data were calculated based on comparison with standards for Arochlor 1221, 1242, 1248 and 1254 (Supelco, Inc.). No worm samples were identified with six of more chlorine atoms. However, the higher chlorinated congeners were identified in the standards. Therefore, the lack of chlorination in the worms was not an analytical artifact. The sum of identifiable PCBs ranged from a barely discernible 0.01 ng/g dry wt in an A. antillarum sample from Bahia de Culebra to 67.71 ng/g dry wt in a P. perlucens sample obtained near the Rio Rincon in the inner Golfo Dulce. S. nudus worm samples from the Cocorocas sand flat in the Golfo de Nicoya had relatively high concentrations of PCBs whether they were purified or not. The samples from Costa Rica are low in PCBs, especially compared to the marine sediment samples measured previously in Costa Rica. This was the first attempt to identify and quantify the presence of PCBs in any marine organisms from the Pacific coast of Costa Rica. (author)

  18. Genetic variation for worm burdens in laying hens naturally infected with gastro-intestinal nematodes.

    Science.gov (United States)

    Wongrak, K; Daş, G; von Borstel, U König; Gauly, M

    2015-01-01

    1. Genetic parameters were determined for the worm burden of the most common gastro-intestinal nematodes in two chicken genotypes after being exposed to free-range farming conditions for a laying period. 2. Seventeen-week-old hens of 2 brown genotypes, Lohmann Brown (LB) plus (n = 230) and LB classic (n = 230), were reared for a laying period and subjected to post-mortem parasitological examinations at 79 weeks (LB plus) or 88 weeks (LB classic) of age. 3. There was no significant difference in faecal egg counts between the genotypes. Almost all hens (>99%) were infected with at least one nematode species. Species-specific nematode prevalence ranged from 85.8% to 99.1% between the two genotypes. Heterakis gallinarum was the most prevalent nematode (98.5%), followed by Ascaridia galli (96.2%) and Capillaria spp. (86.1%). Capillaria spp. were composed of C. obsignata (79%), C. caudinflata (16%) and C. bursata (5%). 4. All phenotypic and genetic correlations among worm counts of different parasite species were positive in combined genotypes (rP ranged from 0.05 to 0.30 and rG ranged from 0.29 to 0.88). A strong genetic correlation (rG = 0.88 ± 0.34) between counts of A. galli and H. gallinarum was quantified. Heritability for total worm burden for LB plus and LB classic, respectively, were 0.55 ± 0.18 and 0.55 ± 0.34. Across both genotypes, the heritability of total worm burden was 0.56 ± 0.16. 5. In conclusion, there is a high variation attributable to genetic background of chickens in their responses to naturally acquired nematode infections. The high positive genetic correlation between counts of closely related worm species (e.g. A. galli and H. gallinarum) may indicate existence of similar genetically determined mechanism(s) in chickens for controlling these nematodes. PMID:25486507

  19. A Robust Cross-Linking Strategy for Block Copolymer Worms Prepared via Polymerization-Induced Self-Assembly

    Science.gov (United States)

    2016-01-01

    A poly(glycerol monomethacrylate) (PGMA) chain transfer agent is chain-extended by reversible addition–fragmentation chain transfer (RAFT) statistical copolymerization of 2-hydroxypropyl methacrylate (HPMA) with glycidyl methacrylate (GlyMA) in concentrated aqueous solution via polymerization-induced self-assembly (PISA). A series of five free-standing worm gels is prepared by fixing the overall degree of polymerization of the core-forming block at 144 while varying its GlyMA content from 0 to 20 mol %. 1H NMR kinetics indicated that GlyMA is consumed much faster than HPMA, producing a GlyMA-rich sequence close to the PGMA stabilizer block. Temperature-dependent oscillatory rheological studies indicate that increasing the GlyMA content leads to progressively less thermoresponsive worm gels, with no degelation on cooling being observed for worms containing 20 mol % GlyMA. The epoxy groups in the GlyMA residues can be ring-opened using 3-aminopropyltriethoxysilane (APTES) in order to prepare core cross-linked worms via hydrolysis-condensation with the siloxane groups and/or hydroxyl groups on the HPMA residues. Perhaps surprisingly, 1H NMR analysis indicates that the epoxy–amine reaction and the intermolecular cross-linking occur on similar time scales. Cross-linking leads to stiffer worm gels that do not undergo degelation upon cooling. Dynamic light scattering studies and TEM analyses conducted on linear worms exposed to either methanol (a good solvent for both blocks) or anionic surfactant result in immediate worm dissociation. In contrast, cross-linked worms remain intact under such conditions, provided that the worm cores comprise at least 10 mol % GlyMA. PMID:27134311

  20. Evaluation of Echinostoma liei worm, metacercaria and redia antigens for schistosomiasis control.

    Science.gov (United States)

    Abdel-Monaem, G; Farid, A; Rabia, I; El-Amir, A

    2015-10-01

    While chemotherepeutic drugs, such as praziquantel, oxamniquine and metrifonate, are currently considered safe and effective drugs for schistosomiasis treatment, reinfection occurs frequently after drug treatment. Thus, a vaccine is sought to provide long-term treatment. Antigens from worm, metacercaria and redia of Echinostoma liei (E. liei) were purified using CNBr-activated Sepharose column, then used for immunization of mice prior to infection with Schistosomiasis mansoni. Worm burden, hepatic and intestinal eggs and oogram count was significantly reduced and that was reflected in normalization of liver architecture. This referred to a significant increase in the tested immunoglobulin level (IgM, IgG1 and IgG2). PMID:26115938

  1. [Chronic disseminated intravascular coagulopathy in a dog with lung worm infection].

    Science.gov (United States)

    Schmitz, S; Moritz, A

    2009-06-01

    The clinical and laboratory findings in a 1-year-old male Jack Russel Terrier dog with lung worm induced coagulopathy are described. The diagnosis was based upon history, clinical findings, radiography, endoscopy, cytology and laboratory results. The presenting complaint was chronic cough. Radiographically, a diffuse interstitial to bronchial lung pattern was observed. Blood analysis revealed thrombocytopaenia and prolonged coagulation times. Disseminated intravascular coagulopathy (DIC) was diagnosed based on D-dimer and fibrinogen measurements, and by thrombelastogram results. After stabilisation of the patient, bronchoscopy with a bronchoalveolar lavage was performed, where large amounts of lung worm larvae were found cytologically. After treatment with fresh frozen plasma and fenbendazole, coagulation parameters improved and the cough resolved. PMID:19496048

  2. Chordodes ferox, a new record of horsehair worms (Nematomorpha, Gordiida) from South Africa

    Science.gov (United States)

    Schmidt-Rhaesa, Andreas; Perissinotto, Renzo

    2016-01-01

    Abstract Three females and one male specimen of a previously unconfirmed species of horsehair worms (Nematomorpha) from South Africa are described using Scanning Electron Microscopy. The females correspond to the description of Chordodes ferox Camerano, 1897, a species previously described from the Democratic Republic of the Congo (Congo-Kinshasa) and an adjacent, not further specified region of the Republic of Congo (Congo-Brazzaville). Characteristic is the presence of enlarged and elevated simple areoles around the base of a thorn areole, in combination with further cuticular characters. This is the latest of a total of six species of horsehair worms reported from South Africa so far. Two species of praying mantids, Polyspilota aeruginosa (Goeze, 1778) and Sphodromantis gastrica Stål, 1858, have been identified as hosts of Chordodes ferox, while its distribution range in the region and the period of adult emergence from the host remain largely unknown. PMID:27047243

  3. Schistosomicidal evaluation of Zanthoxylum naranjillo and its isolated compounds against Schistosoma mansoni adult worms.

    Science.gov (United States)

    Braguine, Caio G; Costa, Eveline S; Magalhães, Lizandra G; Rodrigues, Vanderlei; da Silva Filho, Ademar A; Bastos, Jairo K; Silva, Márcio L A; Cunha, Wilson R; Januário, Ana H; Pauletti, Patrícia M

    2009-01-01

    Chemical investigation of the EtOAc fraction (EF) obtained from the ethanolic extract of Zanthoxylum naranjillo (Rutaceae) leaves (EE) by preparative HPLC resulted in the isolation of protocatechuic acid (1), gallic acid (2), p-hydroxybenzoic acid (3), and 5-O-caffeoylshikimic acid (4). This is the first time that the presence of compounds 1-4 in Z. naranjillo has been reported. Compounds 1-4, the EE, and EF were tested in vitro against Schistosoma mansoni adult worms. The results showed that the S. mansoni daily egg production decreased by 29.8%, 13.5%, 28.4%, 17.7%, 16.3%, and 6.4%, respectively. Compounds 1 and 3 were also able to separate adult worm pairs into male and female. This activity may be correlated with the reduction in egg production, since 1 and 3 showed better inhibitory properties compared with 2 and 4. PMID:20158148

  4. Heavy Worm Burden of Moniliformis in Urban Rats with Histopathological Description

    Directory of Open Access Journals (Sweden)

    Gh Mowlavi

    2011-09-01

    Full Text Available Background: Due to scarcity of human reports, we took advantage of the heaviest infection of M. moniliformis in rats, to describe histopathological and microanatomical valuable useful keys while confronting human occurrences.Methods: Samples were obtained from captured rats in Tehran, capital of Ira, during two dec­ades. Tissue sections were performed through hematoxylin and eosin staining to describe histopa­thological changes in rat's intestines.Results: Totally, nine rats were found infected with M. moniliformis amongst 272 obtained rats. Heavy infection has been distinguished in 2 individuals with parasite burden of 141and 73 adult worms. Cross sections of worms within the lumen show mucosal thickness, infiltration of eosino­philic leukocyte and increase in goblet cells. Conclusion: Beyond the uncommonness of human infection with M. moniliformis unintended infections should not be ignored. Abundance of rats and roaches as definite and intermediate hosts must be considered particularly in countries with poor hygiene.

  5. Biological effects of pyrimethinal on aquatic worms (Tubifex tubifex) under laboratory conditions.

    Science.gov (United States)

    Mosleh, Yahia Youssef; Mofeed, Jelan; Afifi, Mohamed; Almaghrabi, Omar A

    2014-01-01

    Laboratory studies were conducted to determine the effects of different concentrations of pyrimethinal on protein contents, and some oxidative stress in Tubifex tubifex after an exposure of 2, 4, and 7 days. Residues of the fungicide were followed in water and in the worms. In water, pyrimethinal concentration decreased slowly (maximum -6.4 % ± 0.8 % after 2 days for 25 mg L(-1)). In the worms, it increased after 4 days and decreased thereafter. LC50 values were between 49.2 ± 0.58 and 39.5 ± 0.95 mg L(-1) depending on exposure time. The activity of catalase increased in response to the fungicide after 2 days of exposure to 25 mg L(-1) of pyrimethinal (+90 %). The highest decrease of glutathione-S-transferase activity (-29.7 %) was found after 7 days in the presence of 25 mg L(-1). PMID:24213591

  6. Worms With a Single Functional Sensory Cilium Generate Proper Neuron-Specific Behavioral Output

    OpenAIRE

    Senti, Gabriele; Ezcurra, Marina; Löbner, Jana; Schafer, William R.; Swoboda, Peter

    2009-01-01

    Studying the development and mechanisms of sensory perception is challenging in organisms with complex neuronal networks. The worm Caenorhabditis elegans possesses a simple neuronal network of 302 neurons that includes 60 ciliated sensory neurons (CSNs) for detecting external sensory input. C. elegans is thus an excellent model in which to study sensory neuron development, function, and behavior. We have generated a genetic rescue system that allows in vivo analyses of isolated CSNs at both c...

  7. Synergy of Omeprazole and Praziquantel In Vitro Treatment against Schistosoma mansoni Adult Worms

    Science.gov (United States)

    Anderson, Leticia; Venancio, Thiago M.; Nakaya, Helder I.; Miyasato, Patrícia A.; Rofatto, Henrique K.; Zerlotini, Adhemar; Nakano, Eliana; Oliveira, Guilherme; Verjovski-Almeida, Sergio

    2015-01-01

    Background Treatment and morbidity control of schistosomiasis relies on a single drug, praziquantel (PZQ), and the selection of resistant worms under repeated treatment is a concern. Therefore, there is a pressing need to understand the molecular effects of PZQ on schistosomes and to investigate alternative or synergistic drugs against schistosomiasis. Methodology We used a custom-designed Schistosoma mansoni expression microarray to explore the effects of sublethal doses of PZQ on large-scale gene expression of adult paired males and females and unpaired mature females. We also assessed the efficacy of PZQ, omeprazole (OMP) or their combination against S. mansoni adult worms with a survival in vitro assay. Principal Findings We identified sets of genes that were affected by PZQ in paired and unpaired mature females, however with opposite gene expression patterns (up-regulated in paired and down-regulated in unpaired mature females), indicating that PZQ effects are heavily influenced by the mating status. We also identified genes that were similarly affected by PZQ in males and females. Functional analyses of gene interaction networks were performed with parasite genes that were differentially expressed upon PZQ treatment, searching for proteins encoded by these genes whose human homologs are targets of different drugs used for other diseases. Based on these results, OMP, a widely prescribed proton pump inhibitor known to target the ATP1A2 gene product, was chosen and tested. Sublethal doses of PZQ combined with OMP significantly increased worm mortality in vitro when compared with PZQ or OMP alone, thus evidencing a synergistic effect. Conclusions Functional analysis of gene interaction networks is an important approach that can point to possible novel synergistic drug candidates. We demonstrated the potential of this strategy by showing that PZQ in combination with OMP displayed increased efficiency against S. mansoni adult worms in vitro when compared with

  8. Bioavailability of sediment-sorbed naphthalenes to the spiuncluid worm, phascolosoma agassizii

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, J.W.; Moore, L.J.; Blaylock, J.W.; Woodruff, D.L.; Kiesser, S.L.

    1976-10-01

    The objectives of this study were to determine the accumulation and release parameters of naphthalenes for the burrowing peanut worm, (Sipunculida) Phascolosoma agassizii. So that uptake from sediment could be compared to that from contaminated water, the latter was also briefly investigated. Sediment-oil mixtures were produced and used in two ways to examine the variability that might be produced by different types of actual oil spills.

  9. Prediction of C. elegans Longevity Genes by Human and Worm Longevity Networks

    OpenAIRE

    Robi Tacutu; Shore, David E.; Arie Budovsky; João Pedro de Magalhães; Gary Ruvkun; Fraifeld, Vadim E.; Curran, Sean P.

    2012-01-01

    Intricate and interconnected pathways modulate longevity, but screens to identify the components of these pathways have not been saturating. Because biological processes are often executed by protein complexes and fine-tuned by regulatory factors, the first-order protein-protein interactors of known longevity genes are likely to participate in the regulation of longevity. Data-rich maps of protein interactions have been established for many cardinal organisms such as yeast, worms, and humans....

  10. Glow Worms as a Tourist Attraction in Springbrook National Park: Visitor Attitudes and Economic Issues

    OpenAIRE

    Wilson, Clevo; Tisdell, Clement A.; Merritt, David

    2004-01-01

    Insect-based tourism mainly caters to a niche market, but its popularity has been growing in recent years. Despite its popularity this form of tourism has remained under-researched and in a sense its contribution to the tourism industry has gone mostly unnoticed. This paper reports the results of a study undertaken on one form of popular insect-based tourism, namely glow worms. The study was undertaken in Springbrook National Park (Natural Bridge section) southeast Queensland, which has one o...

  11. Response to "Discussion on the systematic position of the Early Cambrian priapulomorph worms"

    Institute of Scientific and Technical Information of China (English)

    HAN Jian; HU Shixue

    2006-01-01

    @@ Due to the combination of complex states of preservation and taphonomies in Chengjiang fossils, Huang et al.[1] expressed different opinions to those of Han et al.[2] on the morphology and systematic position of the fossil priapulomorph worms (Priapulomorpha) based on their additional materials. These diverse opinions are critical in any investigation of the diversity of the Introverta in the Cambrian explosion. However, some of their ideas need to be discussed in further detail.

  12. Comparison between the Nereis diversicolor and Nereis virens marine worms in the transformation of ingested hydrocarbons

    OpenAIRE

    Gilbert, Franck; Desrosiers, Gaston; Hulth, Stefan; Stora, Georges

    2001-01-01

    A feeding experiment was conducted on the marine worm Nereis diversicolor to compare the fate of a hydrocarbon mixture during the gut passage in this species with the hydrocarbon breakdown process demonstrated for Nereis virens. Hydrocarbon dissolution/solubilization processes in the gut of N. diversicolor were found to have similar qualitative and quantitative importance in the hydrocarbon transformation as those observed in N. virens.

  13. Chordodes mizoramensis (Nematomorpha, Gordiida), a new species of horsehair worm from Mizoram, North-East India

    OpenAIRE

    Andreas Schmidt-Rhaesa; Lalramliana

    2011-01-01

    Abstract Chordodes mizoramensis, a new species of freshwater gordiid horsehair worm, is described from Mizoram, NE India on the basis of scanning electron microscopic and morphometric studies. The new species can be distinguished from its congeners in that the apical filaments of the crowned areoles are branched several times, a pattern that has not been observed in other species. An additional distinguishing character is that it has more bulging areoles, which are distributed among simple ar...

  14. Investigation on application of synthetic nutrients for augmenting worm growth rate in vermicomposting

    Directory of Open Access Journals (Sweden)

    Kanimani Thiruganasambadam

    2012-06-01

    Full Text Available An investigation was carried out to scan the influence of synthetic nutrients on Vermicomposting. A mixture of six nutrients (Iron, Manganese, Zinc, Copper, Molybdenum and Boron was introduced to augment the growth of worms (Lumbricus rubellus and to ensure the higher digestion rate of the pre-composted bio-degradable organic waste. Initially green waste was collected from the local vegetable market and pre-composted for about three weeks. Then the pre-composted waste was placed in two identical glass vermireactors. Each reactor was loaded with equal volume of waste (0.024 m³ and worms (40 gm. The pre-composted waste was vermicomposted for a period of 21 days by applying nutrients in one reactor and the other was kept as control (without nutrient. The nutrients were applied in liquid form while moistening the reactor beds and the characteristics of the pre-composted waste, vermicasts and vermi growth rate were studied. Results revealed that the reactor added by nutrients performed better by achieving 41.34% higher waste volume reduction and 42% increase in the worm growth rate.

  15. Metagonimus yokogawai: metacercariae survey in fishes and its development to adult worms in various rodents.

    Science.gov (United States)

    Li, Ming-Hsien; Huang, Hai-I; Chen, Pei-Lain; Huang, Chiung-Hua; Chen, Yu-Hsuan; Ooi, Hong-Kean

    2013-04-01

    A parasitological survey for Metagonimus yokogawai metacercariae was carried out by examining a total of 321 freshwater fish comprising of 7 species. Of the 321 fish samples examined, 182 (56.7%) were found to be infected with M. yokogawai metacercariae. The prevalence of M. yokogawai metacercariae in Opsariichthys pachycephalus was 93.4% (86/92), Zacco platypus 75.0% (30/40), Distoechodon turmirostris 61.3% (38/62), Varicorhinus barbatulus 56.5% (13/23), Hemibarbus labeo 33.3% (1/3), Acrossocheilus formosanus 15.9% (14/88), and 0% in Sinibrama macrops (0/13), respectively. This is the first record of M. yokogawai infection in Z. platypus, D. turmirostris, V. barbatulus, and H. labeo in Taiwan. The major site of predilection of the metacercariae in the fishes was in the scale, but some metacercariae were also observed in the flesh and fins. The M. yokogawai metacercariae were orally inoculated into mice, rat, gerbil, and golden hamster to study their infectivity and also to obtain the adult worms for taxonomic study. Worm recovery in hamsters was 75.3%, in mice was 70.0%, in rats was 23.3%, and in gerbils was 6.0%, respectively. Moreover, larger worms were recovered from the golden hamster. Golden hamster was thus found to be the most susceptible experimental rodent host for the infectivity study of Metagonimus. Besides M. yokogawai, metacercariae of Centrocestus formosanus was also observed in the fishes examined. PMID:23388732

  16. Potential role for mucosal IgA in modulating Haemonchus contortus adult worm infection in sheep.

    Science.gov (United States)

    Hernández, J N; Hernández, A; Stear, M J; Conde-Felipe, M; Rodríguez, E; Piedrafita, D; González, J F

    2016-06-15

    Haemonchus contortus (H. contortus) is a haematophagous parasite which causes important economic losses in small ruminants. On the island of Gran Canaria, two sheep breeds coexist which differ in their susceptibility to the infection with H. contortus; the resistant Canaria Hair Breed (CHB) sheep and the susceptible Canaria Sheep (CS) breed. The major target of resistance mechanisms in CHB sheep are directed to the adult parasite stage, reducing the worm burden, and decreased length and fecundity of surviving worms. Mucosal IgA (mIgA) has been shown to be an important regulator of immunity in Haemonchus and Teladorsagia infections; through correlations with larval stages where such mechanisms as antibody-dependent cell cytotoxicity and enzyme inhibition may mediate resistance. Here for the first time, we demonstrate a significant negative correlation between mIgA and adult worm length and fecundity only in the resistant CHB sheep. In contrast, and as reported in other sheep breeds, mIgA was only negatively correlated against the larval stage in the more susceptible CS breed. This study suggests mIgA may play a role in resistance to both larval and adult stages. PMID:27198794

  17. Self-avoiding worm-like chain model for dsDNA loop formation

    CERN Document Server

    Pollak, Yaroslav; Amit, Roee

    2014-01-01

    We compute for the first time the effects of excluded volume on the probability for double-stranded DNA to form a loop. We utilize a Monte-Carlo algorithm for generation of large ensembles of self- avoiding worm-like chains, which are used to compute the J-factor for varying lengthscales. In the entropic regime, we confirm the scaling-theory prediction of a power-law drop off of -1.92, which is significantly stronger than the -1.5 power-law predicted by the non-self-avoiding worm-like chain model. In the elastic regime, we find that the angle-independent end-to-end chain distribution is highly anisotropic. This anisotropy, combined with the excluded volume constraints, lead to an increase in the J-factor of the self-avoiding worm-like chain by about half an order of magnitude relative to its non-self-avoiding counterpart. This increase could partially explain the anomalous results of recent cyclization experiments, in which short dsDNA molecules were found to have an increased propensity to form a loop.

  18. Nuclear techniques in the biochemistry and experimental chemotherapy of filarial worms

    International Nuclear Information System (INIS)

    There is an almost complete lack of biochemical data on filarial worms of medical importance and most of the available information has been obtained from four laboratory-maintained species, Brugia pahangi, Dipetalonema viteae, Litomosoides carinii and Dirofilaria immitis. Several workers have attempted to study the vector-borne stages of filariae, either by an autoradiographic study of the distribution of radioactive substrates introduced to the mosquito by feeding or by micro-injection into the thorax. Comparison of the levels of folate metabolism in uninfected and B. pahangi-infected Aedes aegypti have also been made. Biochemical studies on adult worms have focussed mainly on carbohydrate and folate metabolism. Those species investigated did not possess significant tricarboxylic acid cycle activity and relied upon glycolysis for carbohydrate catabolism and energy production. B. pahangi and D. immitis cannot synthesize dihydrofolate de novo, but are able to utilize 5-methyl tetrahydrofolate for the production of metabolically active tetrahydrofolate cofactors. Information on folate metabolism is reviewed. Filarial nematodes resemble cestodes and schistosomes in possessing a cuticle which is freely permeable to a wide range of low molecular weight substances. The surface of the cuticle is bounded by antigenic proteins which may be shed from the worms in vivo. Data on the immunological and physiological properties of the surface are discussed. The interaction of standard filaricidal compounds, suramin and diethylcarbamazine, with the biochemical pathways of carbohydrate and folate metabolism are described. (author)

  19. Expression of actin genes in the arrow worm Paraspadella gotoi (Chaetognatha).

    Science.gov (United States)

    Yasuda, E; Goto, T; Makabe, K W; Satoh, N

    1997-12-01

    Arrow worms (the phylum Chaetognatha), one of the major marine planktonic animals, exhibit features characteristic to both deuterostomes and protostomes, and their ancestry therefore remains unknown. As the first step to elucidate the molecular bases of arrow worm phylogeny, physiology and embryology, we isolated cDNA clones for three different actin genes (PgAct1, PgAct2 and PgAct3) from the benthic species Paraspadella gotoi, and examined their expression patterns in adults and juveniles. The amino acid sequences of the three actins resembled each other, with identities ranging from 86% to 92%. However, the patterns of the spatial expression of the genes were independent. The PgAct1 gene might encode a cytoplasmic actin and was expressed in oogenic cells, spermatogenic cells, and cells in the ventral ganglion. The PgAct2 and PgAct3 genes encoded actins of divergent types. The former was expressed in well-developed muscle of the head (gnathic) region and trunk muscle cells, whereas the latter was expressed in muscle of the trunk and tail regions and oogenic cells. These results suggest that, similarly to other metazoans, the chaetognath contains multiple forms of actins, which are expressed in various manners in the adult and juvenile arrow worm. PMID:9520638

  20. Zinc and mechanical prowess in the jaws of Nereis, a marine worm

    Energy Technology Data Exchange (ETDEWEB)

    Lichtenegger, Helga C.; Schoberl, Thomas; Ruokolainen, Janne T.; Cross, Julie O.; Heald, Steve M.; Birkedal, Henrik; Waite, J. Herbert; Stucky, Galen

    2003-08-05

    Higher animals typically rely on calcification to harden certain tissues such as bones and teeth. Some notable exceptions can be found in invertebrates: The fangs, teeth, and mandibles of diverse arthropod species have been reported to contain high levels of zinc. Considerable quantities of zinc also occur in the jaws of the marine polychaete worm Nereis sp. High copper levels in the polychaete worm Glycera dibranchiata recently were attributed to a copper-based biomineral reinforcing the jaws. In the present article, we attempt to unravel the role of zinc in Nereis limbata jaws, using a combination of position-resolved state-of-the-art techniques. It is shown that the local hardness and stiffness of the jaws correlate with the local zinc concentration, pointing toward a structural role for zinc. Zinc always is detected in tight correlation with chlorine, suggesting the presence of a zinc– chlorine compound. No crystalline inorganic phase was found, however, and results from x-ray absorption spectroscopy further exclude the presence of simple inorganic zinc– chlorine compounds in amorphous form. The correlation of local histidine levels in the protein matrix and zinc concentration leads us to hypothesize a direct coordination of zinc and chlorine to the protein. A comparison of the role of the transition metals zinc and copper in the jaws of two polychaete worm species Nereis and Glycera, respectively, is presented.

  1. Zinc and mechanical prowess in the jaws of Nereis, a marine worm

    Energy Technology Data Exchange (ETDEWEB)

    Lichtenegger, Helga C.; Schoberl, Thomas; Ruokolainen, Janne T.; Cross, Julie O.; Heald, Steve M.; Birkedal, Henrik; Waite, J. Herbert; Stucky, Galen

    2003-08-05

    Higher animals typically rely on calcification to harden certain tissues such as bones and teeth. Some notable exceptions can be found in invertebrates: The fangs, teeth, and mandibles of diverse arthropod species have been reported to contain high levels of zinc. Considerable quantities of zinc also occur in the jaws of the marine polychaete worm Nereis sp. High copper levels in the polychaete worm Glycera dibranchiata recently were attributed to a copper-based biomineral reinforcing the jaws. In the present article, we attempt to unravel the role of zinc in Nereis limbata jaws, using a combination of position-resolved state-of-the-art techniques. It is shown that the local hardness and stiffness of the jaws correlate with the local zinc concentration, pointing toward a structural role for zinc. Zinc always is detected in tight correlation with chlorine, suggesting the presence of a zinc-chlorine compound. No crystalline inorganic phase was found, however, and results from x-ray absorption spectroscopy further exclude the presence of simple inorganic zinc-chlorine compounds in amorphous form. The correlation of local histidine levels in the protein matrix and zinc concentration leads us to hypothesize a direct coordination of zinc and chlorine to the protein. A comparison of the role of the transition metals zinc and copper in the jaws of two polychaete worm species Nereis and Glycera, respectively, is presented.

  2. Potential Test of Irradiated Vaccine for Haemonchus Contortus Worm and Food Supplement on Sheep

    International Nuclear Information System (INIS)

    An experiment of vaccines was carried out is one of Nematoda worm present in abomasums or stomach of sheep or goat. The case in the field was high enough, may teach 60% the aim of this study is on observe the effect of gastric worm vaccination irradiated 5000 L3 post challenge wild strain 5000 L3, The parameter of observe were clinic, blood twice description number of adult worms, with 3 treatments as follows; control (K), V2 = twice vaccinations without challenge V1 twice vaccinations with challenge. The result of the study the average of gain (gram); V1=97, V2=91 and K=31.20 (P 6), V1=6.50, V2=5.90 and K=6.10 (P 1=29.30, V2=35.30 and K=27.50 (P 3), V1=9.30, V2=9.00 and K=7.40 (P 1=8.30, V2=9.50 and K=6.20 (P 1 immunity respond of weight gain, erythrocyte and leucocyte to have immunity which is better than the respond of other treatments. (author)

  3. ULTRASTRUCTURAL CHANGES IN Schistosoma mansoni MALE WORMS AFTER in vitro INCUBATION WITH THE ESSENTIAL OIL OF Mentha x villosa Huds

    Science.gov (United States)

    MATOS-ROCHA, Thiago José; CAVALCANTI, Marília Gabriela dos Santos; VERAS, Dyana Leal; FEITOSA, Ana Paula Sampaio; GONÇALVES, Gabriel Gazzoni Araújo; PORTELA-JUNIOR, Nairomberg Cavalcanti; LÚCIO, Ana Silvia Suassuna Carneiro; da SILVA, Anekécia Lauro; PADILHA, Rafael José Ribeiro; MARQUES, Márcia Ortiz Mayo; BARBOSA-FILHO, José Maria; ALVES, Luiz Carlos; BRAYNER, Fábio André

    2016-01-01

    Introduction: The essential oil Mentha x villosa (MVEO) has a wide range of actions, including antibacterial, antifungal, antiprotozoal and schistosomicidal actions. The present study aimed to investigate the ultrastructural changes of MVEO on the tegument of adult Schistosoma mansoni. Materials and Methods: Different concentrations of MVEO were tested on S. mansoni adult worms in vitro. Ultrastructural changes on the tegument of these adult worms were evaluated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results: The MVEO caused the death of all worms at 500 μg mL-1 after 24 h. After 24h of 500 μg mL-1 MVEO treatment, bubble lesions were observed over the entire body of worms and they presented loss of tubercles in some regions of the ventral portion. In the evaluation by TEM, S. mansoni adult worms treated with MVEO, 500 μg mL-1, presented changes in the tegument and vacuoles in the syncytial matrix region. Glycogen granules close to the muscle fibers were visible. Conclusion: The ability of MVEO to cause extensive ultrastructural damage to S. mansoni adult worms correlates with its schistosomicidal effects and confirms earlier findings with S. mansoni. PMID:26910448

  4. Effects of Doxycycline on gene expression in Wolbachia and Brugia malayi adult female worms in vivo

    Directory of Open Access Journals (Sweden)

    Rao Ramakrishna U

    2012-02-01

    Full Text Available Abstract Background Most filarial nematodes contain Wolbachia symbionts. The purpose of this study was to examine the effects of doxycycline on gene expression in Wolbachia and adult female Brugia malayi. Methods Brugia malayi infected gerbils were treated with doxycycline for 6-weeks. This treatment largely cleared Wolbachia and arrested worm reproduction. RNA recovered from treated and control female worms was labeled by random priming and hybridized to the Version 2- filarial microarray to obtain expression profiles. Results and discussion Results showed significant changes in expression for 200 Wolbachia (29% of Wolbachia genes with expression signals in untreated worms and 546 B. malayi array elements after treatment. These elements correspond to known genes and also to novel genes with unknown biological functions. Most differentially expressed Wolbachia genes were down-regulated after treatment (98.5%. In contrast, doxycycline had a mixed effect on B. malayi gene expression with many more genes being significantly up-regulated after treatment (85% of differentially expressed genes. Genes and processes involved in reproduction (gender-regulated genes, collagen, amino acid metabolism, ribosomal processes, and cytoskeleton were down-regulated after doxycycline while up-regulated genes and pathways suggest adaptations for survival in response to stress (energy metabolism, electron transport, anti-oxidants, nutrient transport, bacterial signaling pathways, and immune evasion. Conclusions Doxycycline reduced Wolbachia and significantly decreased bacterial gene expression. Wolbachia ribosomes are believed to be the primary biological target for doxycycline in filarial worms. B. malayi genes essential for reproduction, growth and development were also down-regulated; these changes are consistent with doxycycline effects on embryo development and reproduction. On the other hand, many B. malayi genes involved in energy production, electron

  5. Parasiticidal and brine shrimp cytotoxicity potential of crude methanolic extract of rind of Punica granatum Linn against round worms and tape worms.

    Science.gov (United States)

    Ali, Niaz; Jamil, Ayesha; Shah, Syed Wadood Ali; Shah, Ismail; Ahmed, Ghayour; Junaid, Muhammad; Ahmed, Zahoor

    2015-05-01

    Rind of Punica granatum is traditionally used for anthelmintic purposes. The current work describes the possible anthelmintic activity of crude methanolic extract of Punica granatum (Pg. Cr) against round worms (Ascaridia galli) and the tape worms (Raillietina spiralis). Brine shrimp cytotoxicity is also performed. Brine shrimp cytotoxic activity was tested using different concentrations (1000 μg/mL, 100 μg/mL and 10 μg/mL) of Pg.Cr. In vitro anthelmintic activity of Pg. Cr was determined against the parasites using albendazole and piperazine citrate as standard anthelmintic drugs in concentration 10 mg/ml. LC50 value for Brine shrimp cytotoxicity was 189.44 ±28 μg/mL. In test concentration of 40mg/ml of the Pg. Cr, Raillietina spiralis was paralyzed in 23 minutes. However, for parasiticidal activity (death of the parasite), it took less time (40 minutes) as compared to standard Albendazole. Time taken for death of the parasite Raillietina spiralis, in concentration 40 mg /ml, is 40 min. While standard drugs took more time to kill the Raillietina spiralis. Pg. Cr took 19 minutes to paralyze the Ascaridia galli at concentration 40 mg/ml whereas; it took 48 minutes for to kill the parasite Ascaridia galli. The current work confirms the traditional use of rind of Punica granatum as anthelmintic against Raillietina spiralis and Ascaridia galli. Results of brine shrimp cytotoxicity assay warrant for the isolation of cytotoxic compounds. List of abbreviation- Pg. Cr = Crude methanolic extract of Punica granatum. PMID:26004729

  6. Track-a-worm, an open-source system for quantitative assessment of C. elegans locomotory and bending behavior.

    Science.gov (United States)

    Wang, Sijie Jason; Wang, Zhao-Wen

    2013-01-01

    A major challenge of neuroscience is to understand the circuit and gene bases of behavior. C. elegans is commonly used as a model system to investigate how various gene products function at specific tissue, cellular, and synaptic foci to produce complicated locomotory and bending behavior. The investigation generally requires quantitative behavioral analyses using an automated single-worm tracker, which constantly records and analyzes the position and body shape of a freely moving worm at a high magnification. Many single-worm trackers have been developed to meet lab-specific needs, but none has been widely implemented for various reasons, such as hardware difficult to assemble, and software lacking sufficient functionality, having closed source code, or using a programming language that is not broadly accessible. The lack of a versatile system convenient for wide implementation makes data comparisons difficult and compels other labs to develop new worm trackers. Here we describe Track-A-Worm, a system rich in functionality, open in source code, and easy to use. The system includes plug-and-play hardware (a stereomicroscope, a digital camera and a motorized stage), custom software written to run with Matlab in Windows 7, and a detailed user manual. Grayscale images are automatically converted to binary images followed by head identification and placement of 13 markers along a deduced spline. The software can extract and quantify a variety of parameters, including distance traveled, average speed, distance/time/speed of forward and backward locomotion, frequency and amplitude of dominant bends, overall bending activities measured as root mean square, and sum of all bends. It also plots worm travel path, bend trace, and bend frequency spectrum. All functionality is performed through graphical user interfaces and data is exported to clearly-annotated and documented Excel files. These features make Track-A-Worm a good candidate for implementation in other labs. PMID

  7. Track-a-worm, an open-source system for quantitative assessment of C. elegans locomotory and bending behavior.

    Directory of Open Access Journals (Sweden)

    Sijie Jason Wang

    Full Text Available A major challenge of neuroscience is to understand the circuit and gene bases of behavior. C. elegans is commonly used as a model system to investigate how various gene products function at specific tissue, cellular, and synaptic foci to produce complicated locomotory and bending behavior. The investigation generally requires quantitative behavioral analyses using an automated single-worm tracker, which constantly records and analyzes the position and body shape of a freely moving worm at a high magnification. Many single-worm trackers have been developed to meet lab-specific needs, but none has been widely implemented for various reasons, such as hardware difficult to assemble, and software lacking sufficient functionality, having closed source code, or using a programming language that is not broadly accessible. The lack of a versatile system convenient for wide implementation makes data comparisons difficult and compels other labs to develop new worm trackers. Here we describe Track-A-Worm, a system rich in functionality, open in source code, and easy to use. The system includes plug-and-play hardware (a stereomicroscope, a digital camera and a motorized stage, custom software written to run with Matlab in Windows 7, and a detailed user manual. Grayscale images are automatically converted to binary images followed by head identification and placement of 13 markers along a deduced spline. The software can extract and quantify a variety of parameters, including distance traveled, average speed, distance/time/speed of forward and backward locomotion, frequency and amplitude of dominant bends, overall bending activities measured as root mean square, and sum of all bends. It also plots worm travel path, bend trace, and bend frequency spectrum. All functionality is performed through graphical user interfaces and data is exported to clearly-annotated and documented Excel files. These features make Track-A-Worm a good candidate for implementation in

  8. Examination of the relationship between host worm community structure on transmission of the parasite, Myxobolus cerebralis by developing taxon-specific probes for multiplex qPCR to identify worm taxa in stream communities

    Science.gov (United States)

    Fytilis, N.; Lamb, R.; Kerans, B.; Stevens, L.; Rizzo, D. M.

    2011-12-01

    Fish diseases are often caused by waterborne parasites, making them ideal systems for modeling the non-linear relationships between disease dynamics, stream dwelling oligochaete communities and geochemical features. Myxobolus cerebralis, the causative agent of whirling disease in salmonid fishes, has been a major contributor to the loss of wild rainbow trout populations in numerous streams within the Intermountain West. The parasite alternates between an invertebrate and vertebrate host, being transmitted between the sediment feeding worm Tubifex tubifex (T.tubifex) and salmonid fishes. Worm community biodiversity and abundance are influenced by biogeochemical features and have been linked to disease severity in fish. The worm (T.tubifex) lives in communities with 3-4 other types of worms in stream sediments. Unfortunately, taxonomic identification of oligochaetes is largely dependent on morphological characteristics of sexually mature adults. We have collected and identified ~700 worms from eight sites using molecular genetic probes and a taxonomic key. Additionally, ~1700 worms were identified using only molecular genetic probes. To facilitate distinguishing among tubificids, we developed two multiplex molecular genetic probe-based quantitative polymerase reaction (qPCR) assays to assess tubificid communities in the study area. Similar qPCR techniques specific for M.cerebralis used to determine if individual worms were infected with the parasite. We show how simple Bayesian analysis of the qPCR data can predict the worm community structure and reveal relationships between biodiversity of host communities and host-parasite dynamics. To our knowledge, this is the first study that combines molecular data of both the host and the parasite to examine the effects of host community structure on the transmission of a parasite. Our work can be extended to examine the links between worm community structure and biogeochemical features using molecular genetics and Bayesian

  9. Worm peptidomics

    Directory of Open Access Journals (Sweden)

    Steven J. Husson

    2014-06-01

    Full Text Available Bioactive peptides are present in all metazoan species where they orchestrate diverse functions. In the last decade, high-throughput approaches based on mass spectrometry helped the identification of endogenously occurring peptides in different species. We here review biochemical strategies to obtain sequence information of natural (non-tryptic peptides in Caenorhabditis elegans and in the related nematodes Caenorhabditis briggsae and Ascaris suum with particular attention for sample preparation and methodology. In addition, we describe seven new C. elegans neuropeptides that we recently discovered by sequencing additional peptides. Finally, we explain how differential peptidomics approaches were used to characterize key neuropeptide processing enzymes.

  10. WormScan: a technique for high-throughput phenotypic analysis of Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Mark D Mathew

    Full Text Available BACKGROUND: There are four main phenotypes that are assessed in whole organism studies of Caenorhabditis elegans; mortality, movement, fecundity and size. Procedures have been developed that focus on the digital analysis of some, but not all of these phenotypes and may be limited by expense and limited throughput. We have developed WormScan, an automated image acquisition system that allows quantitative analysis of each of these four phenotypes on standard NGM plates seeded with E. coli. This system is very easy to implement and has the capacity to be used in high-throughput analysis. METHODOLOGY/PRINCIPAL FINDINGS: Our system employs a readily available consumer grade flatbed scanner. The method uses light stimulus from the scanner rather than physical stimulus to induce movement. With two sequential scans it is possible to quantify the induced phototactic response. To demonstrate the utility of the method, we measured the phenotypic response of C. elegans to phosphine gas exposure. We found that stimulation of movement by the light of the scanner was equivalent to physical stimulation for the determination of mortality. WormScan also provided a quantitative assessment of health for the survivors. Habituation from light stimulation of continuous scans was similar to habituation caused by physical stimulus. CONCLUSIONS/SIGNIFICANCE: There are existing systems for the automated phenotypic data collection of C. elegans. The specific advantages of our method over existing systems are high-throughput assessment of a greater range of phenotypic endpoints including determination of mortality and quantification of the mobility of survivors. Our system is also inexpensive and very easy to implement. Even though we have focused on demonstrating the usefulness of WormScan in toxicology, it can be used in a wide range of additional C. elegans studies including lifespan determination, development, pathology and behavior. Moreover, we have even adapted the

  11. Targeted selective treatment for worm management--how do we sell rational programs to farmers?

    Science.gov (United States)

    van Wyk, J A; Hoste, H; Kaplan, R M; Besier, R B

    2006-07-31

    Seriously escalating global anthelmintic resistance in gastrointestinal nematodes of small ruminants has spawned a variety of alternatives to anthelmintics for worm management, based on the need for sustainable Integrated Parasite Management (sIPM). Pivotal to the sIPM approach is the concept of refugia, the proportion of a given parasite population that escapes exposure to control measures. By balancing drug applications with the maintenance of refugia, the accumulation of anthelmintic resistance alleles in worm populations can be considerably delayed, while still providing good levels of control. The over-dispersed nature of parasitic infections provides an opportunity to achieve this balance, by targeting treatments to the members of a flock or herd that are least tolerant to nematode infection. However, implementation of this strategy has only recently become feasible, with the development of the FAMACHA((c)) system for clinical evaluation of anaemia due to haemonchosis. Subsequently, the use of milk yields has proven an effective indicator in dairy goats infected predominantly with nematodes other than Haemonchus contortus. In addition, short-term weight changes and perhaps also body condition scoring may provide indices of parasitism, permitting the rapid identification of animals likely to benefit from treatment. However, sIPM and refugia-based approaches are more complex than whole-flock treatments in conventional programs, and adoption by farmers is most likely where the theoretical basis is understood. As close communication with informed advisors is generally limited, there is a danger that sIPM will remain a theoretical concept without alternative modes of communication. The development of computer-based decision support programs, which use epidemiological, seasonal and clinical information to provide recommendations for specific situations, should be accorded high priority in the future development of worm management systems. PMID:16774807

  12. The effects of chronic radiation on reproductive success of the polychaete worm Neanthes arenaceodentata

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, F.L.; Anderson, S.L.

    1988-12-01

    The effects of lifetime exposure to chronic irradiation on reproductive success were assessed for laboratory populations of the polychaete worm Neanthes arenaceodentata. Lifetime exposure was initiated upon the spawning of the P1 female and was terminated upon spawning of the F1 female. Groups of experimental worms received either no radiation (controls) or 0.19, 2.1, or 17 mGy/h. The total dose received by the worms was either background or approximately 0.55, 6.5, or 54 Gy, respectively. The broods from the F1 mated pairs were sacrificed before hatching occurred, and information was obtained on brood size, on the number of normal and abnormal embryos, and on the number of embryos that were living, dying, and dead. The mean number of embryos in the broods from the F1 females exposed to lifetime radiation of 0.19 and 2.1 mGy/h was not significantly different from the mean number of embryos from control females; however, the mean number of embryos was different from those F1 females exposed to 17 mGy/h. There was a significant reduction in the number of live embryos in the broods from the F1 mated pairs that were exposed to the lowest dose rate given, 0.19 mGy/h, as well as those exposed to 2.1 and 17 mGy/h. Also, increased percentages of abnormal embryos were determined in the broods of all the radiation-exposed groups. 39 refs., 10 figs., 15 tabs.

  13. Facile Synthesis of Worm-like Micelles by Visible Light Mediated Dispersion Polymerization Using Photoredox Catalyst.

    Science.gov (United States)

    Yeow, Jonathan; Xu, Jiangtao; Boyer, Cyrille

    2016-01-01

    Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins with the synthesis of a hydrophilic poly(oligo(ethylene glycol) methyl ether methacrylate) (POEGMA) homopolymer using reversible addition-fragmentation chain-transfer (RAFT) polymerization. Under mild visible light irradiation (λ = 460 nm, 0.7 mW/cm(2)), this macro-chain transfer agent (macro-CTA) in the presence of a ruthenium based photoredox catalyst, Ru(bpy)3Cl2 can be chain extended with a second monomer to form a well-defined block copolymer in a process known as Photoinduced Electron Transfer RAFT (PET-RAFT). When PET-RAFT is used to chain extend POEGMA with benzyl methacrylate (BzMA) in ethanol (EtOH), polymeric nanoparticles with different morphologies are formed in situ according to a polymerization-induced self-assembly (PISA) mechanism. Self-assembly into nanoparticles presenting POEGMA chains at the corona and poly(benzyl methacrylate) (PBzMA) chains in the core occurs in situ due to the growing insolubility of the PBzMA block in ethanol. Interestingly, the formation of highly pure worm-like micelles can be readily monitored by observing the onset of a highly viscous gel in situ due to nanoparticle entanglements occurring during the polymerization. This process thereby allows for a more reproducible synthesis of worm-like micelles simply by monitoring the solution viscosity during the course of the polymerization. In addition, the light stimulus can be intermittently applied in an ON/OFF manner demonstrating temporal control over the nanoparticle morphology. PMID:27340940

  14. Animal-sediment interactions: the effect of ingestion and excretion by worms on mineralogy

    Science.gov (United States)

    Needham, S. J.; Worden, R. H.; McIlroy, D.

    2004-09-01

    By controlled experiments that simulate marine depositional environments, it is shown that accelerated weathering and clay mineral authigenesis occur during the combined process of ingestion, digestion and excretion of fine-grained sediment by two species of annelid worms. Previously characterized synthetic mud was created using finely ground, low-grade metamorphic slate (temperature approximately 300°C) containing highly crystalline chlorite and muscovite. This was added to experiment and control tanks along with clean, wind-blown sand. Faecal casts were collected at regular intervals from the experimental tanks and, less frequently, from the control tanks. Over a period of many months the synthetic mud (slate) proved to be unchanged in the control tanks, but was significantly different in faecal casts from the experimental tanks that contained the worms Arenicola marina and Lumbricus terrestris. Chlorite was preferentially destroyed during digestion in the gut of A. marina. Both chlorite and muscovite underwent XRD peak broadening with a skew developing towards higher lattice spacing, characteristic of smectite formation. A neoformed Fe-Mg-rich clay mineral (possibly berthierine) and as-yet undefined clay minerals with very high d-spacing were detected in both A. marina and L. terrestris cast samples. We postulate that a combination of the low pH and bacteria-rich microenvironment in the guts of annelid worms may radically accelerate mineral dissolution and clay mineral precipitation processes during digestion. These results show that macrobiotic activity significantly accelerates weathering and mineral degradation as well as mineral authigenesis. The combined processes of sediment ingestion and digestion thus lead to early diagenetic growth of clay minerals in clastic sediments.

  15. The effects of chronic radiation on reproductive success of the polychaete worm Neanthes arenaceodentata

    International Nuclear Information System (INIS)

    The effects of lifetime exposure to chronic irradiation on reproductive success were assessed for laboratory populations of the polychaete worm Neanthes arenaceodentata. Lifetime exposure was initiated upon the spawning of the P1 female and was terminated upon spawning of the F1 female. Groups of experimental worms received either no radiation (controls) or 0.19, 2.1, or 17 mGy/h. The total dose received by the worms was either background or approximately 0.55, 6.5, or 54 Gy, respectively. The broods from the F1 mated pairs were sacrificed before hatching occurred, and information was obtained on brood size, on the number of normal and abnormal embryos, and on the number of embryos that were living, dying, and dead. The mean number of embryos in the broods from the F1 females exposed to lifetime radiation of 0.19 and 2.1 mGy/h was not significantly different from the mean number of embryos from control females; however, the mean number of embryos was different from those F1 females exposed to 17 mGy/h. There was a significant reduction in the number of live embryos in the broods from the F1 mated pairs that were exposed to the lowest dose rate given, 0.19 mGy/h, as well as those exposed to 2.1 and 17 mGy/h. Also, increased percentages of abnormal embryos were determined in the broods of all the radiation-exposed groups. 39 refs., 10 figs., 15 tabs

  16. Characterization of the N-glycans of female Angiostrongylus cantonensis worms.

    Science.gov (United States)

    Veríssimo, Carolina M; Morassutti, Alessandra L; von Itzstein, Mark; Sutov, Grigorij; Hartley-Tassell, Lauren; McAtamney, Sarah; Dell, Anne; Haslam, Stuart M; Graeff-Teixeira, Carlos

    2016-07-01

    Glycoconjugates play a crucial role in the host-parasite relationships of helminthic infections, including angiostrongyliasis. It has previously been shown that the antigenicity of proteins from female Angiostrongylus cantonensis worms may depend on their associated glycan moieties. Here, an N-glycan profile of A. cantonensis is reported. A total soluble extract (TE) was prepared from female A. cantonensis worms and was tested by western blot before and after glycan oxidation or N- and O-glycosidase treatment. The importance of N-glycans for the immunogenicity of A. cantonensis was demonstrated when deglycosylation of the TE with PNGase F completely abrogated IgG recognition. The TE was also fractionated using various lectin columns [Ulex europaeus (UEA), concanavalin A (Con A), Arachis hypogaea (PNA), Triticum vulgaris (WGA) and Lycopersicon esculentum (LEA)], and then each fraction was digested with PNGase F. Released N-glycans were analyzed with matrix-assisted laser desorption ionization (MALDI)-time-of-flight (TOF)-mass spectrometry (MS) and MALDI-TOF/TOF-MS/MS. Complex-type, high mannose, and truncated glycan structures were identified in all five fractions. Sequential MALDI-TOF-TOF analysis of the major MS peaks identified complex-type structures, with a α1-6 fucosylated core and truncated antennas. Glycoproteins in the TE were labeled with BodipyAF558-SE dye for a lectin microarray analysis. Fluorescent images were analyzed with ProScanArray imaging software followed by statistical analysis. A total of 29 lectins showed positive binding to the TE. Of these, Bandeiraea simplicifolia (BS-I), PNA, and Wisteria floribunda (WFA), which recognize galactose (Gal) and N-acetylgalactosamine (GalNAc), exhibited high affinity binding. Taken together, our findings demonstrate that female A. cantonensis worms have characteristic helminth N-glycans. PMID:27107931

  17. Epidemiology of the eye worm Thelazia callipaeda in cats from southern Switzerland.

    Science.gov (United States)

    Motta, B; Nägeli, F; Nägeli, C; Solari-Basano, F; Schiessl, B; Deplazes, P; Schnyder, M

    2014-07-14

    Thelazia callipaeda is a spiruroid nematode of dogs, cats and wild carnivores transmitted by zoophilic drosophilid Phortica flies and found in an increasing number of European countries. In cats the disease is diagnosed sporadically. This study presents an epidemiological investigation of feline thelaziosis, performed in southern Ticino, Switzerland, an endemic area for T. callipaeda. Between January 2009 and July 2011 2171 cats, having outdoor access and presenting for various reasons, were examined by in-depth eye examinations, and clinical and anamnestic data were collected. The overall prevalence of T. callipaeda in the study area was 0.8% (17/2171 cats, 95% confidence interval: 0.5-1.3%). Among cats showing ocular illness, the prevalence was 9.2% (11/120, CI: 4.7-15.8%). Cats with eye worms had no international travel history and were significantly more often diagnosed between June and December than during other months. With one exception, one single eye per cat was infested, each harboring between 1 and 10 eye worms (arithmetic mean: 2.8 per cat). One cat presented with conjunctivitis and ulcers, seven with conjunctivitis only and 3 with a mildly increased lacrimation, while 6 cats were asymptomatic. Significantly more male than female cats had eye worms and cats older than one year were overrepresented. No pure-bred cats were infested. This study confirms the establishment of this potentially zoonotic parasite in cats from the study area. Due to the clinical relevance and pain caused by the infestations, increased disease awareness and in depth eye examination for the detection of T. callipaeda in cats are recommended, even in absence of obvious clinical signs, in order to initiate appropriate anthelmintic treatment. PMID:24810375

  18. Fossils of hydrothermal vent worms from Cretaceous sulfide ores of the Samail ophiolite, Oman

    Science.gov (United States)

    Haymon, R.M.; Koski, R.A.; Sinclair, C.

    1984-01-01

    Fossil worm tubes of Cretaceous age preserved in the Bayda massive sulfide deposit of the Samail ophiolite, Oman, are apparently the first documented examples of fossils embedded in massive sulfide deposits from the geologic record. The geologic setting of the Bayda deposit and the distinctive mineralogic and textural features of the fossiliferous samples suggest that the Bayda sulfide deposit and fossil fauna are remnants of a Cretaceous sea-floor hydrothermal vent similar to modern hot springs on the East Pacific Rise and the Juan de Fuca Ridge.

  19. Observations on the ecology and reproductive biology of the sipunculan worm Aspidosiphon muelleri in temperate waters

    OpenAIRE

    Ferrero-Vicente, Luis Miguel; Marco-Méndez, Candela; Loya-Fernández, Angel; Sánchez-Lizaso, José Luis

    2014-01-01

    A population of the sipunculan worm Aspidosiphon muelleri, located in temperate waters of the western Mediterranean Sea, was monitored monthly for a year. Some aspects related to its ecology and reproductive biology are shown in the present work. The sex-ratio for this population was close to 1:1 (54% females vs 46% males), thus indicating a dioecious reproduction, although showing a lack of sexual dimorphism. Oocytes were detected in females from 4–5 mm; this size might be reached by A. muel...

  20. Organophilic worm-like ruthenium nanoparticles catalysts by the modification of CTAB on montmorillonite supports.

    Science.gov (United States)

    Zhou, Limei; Qi, Xiaolong; Jiang, Xiaohui; Zhou, Yafen; Fu, Haiyan; Chen, Hua

    2013-02-15

    A supported Ru catalyst was prepared by using cetyltrimethylammonium bromide (CTAB) intercalated montmorillonite as the supporting matrix. The as-prepared Ru catalyst was subsequently characterized by XRD, XPS, N(2) sorption, TEM, and dispersibility measurement. The results showed that the Ru nanoparticles were in the modified montmorillonite interlayers, and the morphology of Ru nanoparticle was worm-like. Moreover, this supported Ru catalyst could be well dispersed in organic solvents such as toluene. The catalyst exhibited high activity and selectivity in the hydrogenation of quinoline even without stirring. PMID:23141762

  1. Regularity of the Szeg\\"o projection on model worm domains

    OpenAIRE

    Monguzzi, Alessandro; Peloso, Marco M.

    2016-01-01

    In this paper we study the regularity of the Szeg\\"o projection on Lebesgue and Sobolev spaces on the boundary of the unbounded model worm domain $D'_\\beta$. We consider the Hardy space $H^2(D'_\\beta)$. Denoting by $bD'_\\beta$ the boundary of $D'_\\beta$, it is classical that $H^2(D'_\\beta)$ can be identified with the closed subspace of $L^2(bD'_\\beta,d\\sigma)$, denoted by $H^2(bD'_\\beta)$, consisting of the boundary values of functions in $H^2(D'_\\beta)$, where $d\\sigma$ is the induced Lebesg...

  2. Path-integral theory of an axially confined worm-like chain

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.A. [Randall Centre for Molecular Mechanisms of Cell Function, King' s College London, London (United Kingdom)

    2001-06-01

    A path-integral formulation is developed for the thermodynamic properties of a worm-like chain moving on a surface and laterally confined by a harmonic potential. The free energy of the chain is calculated as a function of its length and boundary conditions at each end. Distribution functions for chain displacements can be constructed by utilizing the Markov property as a function of displacement {phi}(s) and its derivative d{phi}(s)/ds along the path. These quantities are also calculated in the presence of pinning sites which impose fixed positive or negative displacements, foreshadowing their application to a model for the regulation of striated muscle. (author)

  3. Schistosoma mansoni: quantitative aspects of the fertility and survival of worms obtained from irradiated cercariae (3 Krad), in mice

    International Nuclear Information System (INIS)

    The effect of gamma irradiation on the fertility of female mice, as well as the survival of worms in their portal system, have been observed in four groups of outbred albino mice (Mus musculus), experimentally infected with ca 450 cercariae of Schistosoma mansoni (LE and SJ strains), by transcutaneous route. The cercariae used were a) non-irradiated (control groups), and b) irradiated with 3 Krad of gamma irradiation (Co-60). From the 33rd day on, some stability in the population of surviving worm could be observed. This population remained constant till the end of the observation period (90th day), notedly in relation to the LE strain . Thus, it was concluded that gamma irradiation (at the dose of 3 Krad) is able to hinder the worm egg production in 98.1% of the infected mice. Further, it was observed that the few detected eggs were dead. Females were found to be more resistant to irradiation. The irradiation effect on the mortality of male worms was statistically significant scarcely from the 61st day on. The long period of permanence of the sterile adult irradiated worms in the portal system of mice and their probable involvement in the development of immuno-protection (the so-called concomitant immunity, without the immuno-pathological involvements for the host) are here discussed. (author)

  4. Approach to the resistance of exportation tebo worms when irradiated with gamma ray through a quarantine treatment

    International Nuclear Information System (INIS)

    The tebo worms or butterworms (Chilecomadia moorei) are widely used in Chile in fishing, and so are in the international markets although there are some countries, that use these species, to a less extent for preparing food reptiles. Some foreign countries requirements demand, from the exporters, to carry out quarantine treatments related to the sterilization by ionizing energy, however customers need to make sure about their products safety and that is why it is compulsory to establish limits in connection with worms' irradiation resistance. The irradiation effect on a worms sample using doses of 0.3; 0.45; 0.6 and 0.9 kGy was studied macroscopically, after 1 hour, and then 30, 60 and 90 days after the treatment. One of the equipment utilized had a Cobalt 60 source, where as the other one had Cesium 137 irradiators, with a dose rate of 42.7 Gy minute (min)-1 and 37.1 Gy min-1, respectively. The results concluded that tebo worms can resist more than 3 times the doses suggested by the meta countries without reducing the population drastically, nevertheless it is required to increase the number of worms to be analyzed in order to validate the findings. (author)

  5. Partitioning and accumulation rates of polycyclic aromatic hydrocarbons into polydimethylsiloxane thin films and black worms from aqueous samples

    International Nuclear Information System (INIS)

    Partition equilibriums and extraction rates of polycyclic aromatic hydrocarbons (PAHs) were examined for live biomonitoring with oligochaetes (black worms, Lumbriculus variegatus) and for high surface area chemical passive samplers constructed from polydimethylsiloxane thin film. The goals were to better understand the principles of bioconcentration by aquatic organisms and to aid in the design of a convenient and simple chemical monitoring tool to replace the use of live animals. The worms and films were exposed simultaneously to the contaminated water stream. In the initial extraction stage, similar extracted amount per surface area indicated that thin-film samplers could mimic the behavior of worms for passive sampling. Equilibrium was reached faster by the thin films than by the worms. A good linear relationship between the bioconcentration factors and the film-water partition coefficients of PAHs was found, which demonstrated the feasibility of thin-film sampler for determining the bioavailability of PAHs in water. Compared to the lengthy and inconvenient process of liquid-liquid extraction in worm treatment, thin-film technique simplifies the sample pretreatment procedure by integrating sampling and sample preparation.

  6. Integrating immune mechanisms to model nematode worm burden: an example in sheep.

    Science.gov (United States)

    Garnier, Romain; Grenfell, Bryan T; Nisbet, Alasdair J; Matthews, Jacqueline B; Graham, Andrea L

    2016-06-01

    Gastrointestinal nematodes represent important sources of economic losses in farmed ruminants, and the increasing frequency of anthelmintic resistance requires an increased ability to explore alternative strategies. Theoretical approaches at the crossroads of immunology and epidemiology are valuable tools in that context. In the case of Teladorsagia circumcincta in sheep, the immunological mechanisms important for resistance are increasingly well-characterized. However, despite the existence of a wide range of theoretical models, there is no framework integrating the characteristic features of this immune response into a tractable phenomenological model. Here, we propose to bridge that gap by developing a flexible modelling framework that allows for variability in nematode larval intake which can be used to track the variations in worm burdens. We parameterize this model using data from trickle infection of sheep and show that using simple immunological assumptions, our model can capture the dynamics of both adult worm burdens and nematode fecal egg counts. In addition, our analysis reveals interesting dose-dependent effects on the immune response. Finally, we discuss potential developments of this model and highlight how an improved cross-talk between empiricists and theoreticians would facilitate important advances in the study of infectious diseases. PMID:26283186

  7. Modification design method for an enveloping hourglass worm gear with consideration of machining and misalignment errors

    Science.gov (United States)

    Deng, Xingqiao; Wang, Jinge; Horstemeyer, Mark F.

    2013-09-01

    The influences of machining and misalignment errors play a very critical role in the performance of the anti-backlash double-roller enveloping hourglass worm gear(ADEHWG). However, a corresponding efficient method for eliminating or reducing these errors on the tooth profile of the ADEHWG is seldom reported. The gear engagement equation and tooth profile equation for considering six different errors that could arise from the machining and gear misalignment are derived from the theories of differential geometry and gear meshing. Also, the tooth contact analysis(TCA) is used to systematically investigate the influence of the machining and misalignment errors on the contact curves and the tooth profile by means of numerical analysis and three-dimensional solid modeling. The research results show that vertical angular misalignment of the worm wheel(Δ β) has the strongest influences while the tooth angle error(Δ α) has the weakest influences on the contact curves and the tooth profile. A novel efficient approach is proposed and used to minimize the effect of the errors in manufacturing by changing the radius of the grinding wheel and the approaching point of contact. The results from the TCA and the experiment demonstrate that this tooth profile design modification method can indeed reduce the machining and misalignment errors. This modification design method is helpful in understanding the manufacturing technology of the ADEHWG.

  8. The landscape of human genes involved in the immune response to parasitic worms

    Directory of Open Access Journals (Sweden)

    Fumagalli Matteo

    2010-08-01

    Full Text Available Abstract Background More than 2 billion individuals worldwide suffer from helminth infections. The highest parasite burdens occur in children and helminth infection during pregnancy is a risk factor for preterm delivery and reduced birth weight. Therefore, helminth infections can be regarded as a strong selective pressure. Results Here we propose that candidate susceptibility genes for parasitic worm infections can be identified by searching for SNPs that display a strong correlation with the diversity of helminth species/genera transmitted in different geographic areas. By a genome-wide search we identified 3478 variants that correlate with helminth diversity. These SNPs map to 810 distinct human genes including loci involved in regulatory T cell function and in macrophage activation, as well as leukocyte integrins and co-inhibitory molecules. Analysis of functional relationships among these genes identified complex interaction networks centred around Th2 cytokines. Finally, several genes carrying candidate targets for helminth-driven selective pressure also harbour susceptibility alleles for asthma/allergy or are involved in airway hyper-responsiveness, therefore expanding the known parallelism between these conditions and parasitic infections. Conclusions Our data provide a landscape of human genes that modulate susceptibility to helminths and indicate parasitic worms as one of the major selective forces in humans.

  9. Antischistosomal activity of a calcium channel antagonist on schistosomula and adult Schistosoma mansoni worms

    Directory of Open Access Journals (Sweden)

    Vanessa Silva-Moraes

    2013-08-01

    Full Text Available Current schistosomiasis control strategies are largely based on chemotherapeutic agents and a limited number of drugs are available today. Praziquantel (PZQ is the only drug currently used in schistosomiasis control programs. Unfortunately, this drug shows poor efficacy in patients during the earliest infection phases. The effects of PZQ appear to operate on the voltage-operated Ca2+channels, which are located on the external Schistosoma mansoni membrane. Because some Ca2+channels have dihydropyridine drug class (a class that includes nifedipine sensitivity, an in vitro analysis using a calcium channel antagonist (clinically used for cardiovascular hypertension was performed to determine the antischistosomal effects of nifedipine on schistosomula and adult worm cultures. Nifedipine demonstrated antischistosomal activity against schistosomula and significantly reduced viability at all of the concentrations used alone or in combination with PZQ. In contrast, PZQ did not show significant efficacy when used alone. Adult worms were also affected by nifedipine after a 24 h incubation and exhibited impaired motility, several lesions on the tegument and intense contractility. These data support the idea of Ca2+channels subunits as drug targets and favour alternative therapeutic schemes when drug resistance has been reported. In this paper, strong arguments encouraging drug research are presented, with a focus on exploring schistosomal Ca2+channels.

  10. Immunological responses of sheep against adult worm extract antigen of Fasciola gigantica

    Directory of Open Access Journals (Sweden)

    S Widjajanti

    1999-06-01

    Full Text Available Immunological responses of sheep against adult worm extract antigen of Fasciola gigantica were evaluated in an effort to identify the protein antigen for the candidate of vaccine. In this study the protein antigen from adult worms was extracted, and the extract antigen was then intramuscularly injected into 4 groups of 5 sheep. Two groups received one injection, these included one group injected only with extract antigen and the other group injected with extract antigen emulsified in Quil A adjuvant. The other two groups received two injections with a two week interval, these included one group injected only with extract antigen and the other group injected with extract antigen emulsified in Quil A adjuvant. Three weeks later all of the sheep were challenged with 300 metacercariae of F. gigantica. The antibody titer was monitored every two weeks by using ELISA and the protein profile from each group was compared by using western blotting. Fifteen weeks after challenged all of the sheep were killed and the liver flukes were collected from the liver and counted. The results showed that the antibody titer was higher in the group which received two injections, and the additional of Quil A adjuvant gave much better protection from the infection of F. gigantica (57% and could avoid the death of the sheep than twice injection of antigen without Quil A adjuvant (37%.

  11. Histological changes in the testes of gamma irradiated cotton leaf worm Spodoptera Littoralis (Boisd.). Vol. 4

    International Nuclear Information System (INIS)

    Male adults, less than 24 hours, of cotton leaf worm, S. Littoralis (Boisd.) were gamma irradiated with 100, 150 and 200 Gy and mated with normal females. The resulting males of each generation were used for mating normal females throughout three successive generations. Dissection of adult male parents immediately after irradiation showed no histological effects on testes. The volumes of testes of F1, F2 and F3 generations of cotton leaf worm male moths were significantly affected by the radiation doses applied to parental males. The effects on internal anatomy and histology of the male reproductive system confirm that Gy had minimal effect on the volume and the structure of the testes among the three successive generations. Most of the sperm bundles appeared normal and the individual sperm was fully formed indicating normal metamorphosis. However, a dose of 150 Gy showed morphological abnormalities and retardation in sperm maturation. At 200 Gy the volume and structure of the testes were severely affected. Damage in the testes was highest among F1, and was minimized in the other generations. 10 figs., 1 tab

  12. Simulation of the lattice φ4 quantum field theory with the worm algorithm

    International Nuclear Information System (INIS)

    Full text: In this communication we will present results of Monte Carlo simulations of the φ4 quantum field theory on a (1 + 1) lattice employing the recently-proposed worm algorithm. In Monte Carlo simulations, the efficiency of an algorithm is measured in terms of a dynamical critical exponent z, that is related with the autocorrelation time τ of measurements as τ ∝ Lz, where L is the lattice length. The autocorrelation time provides a measure of the 'memory' of the Monte Carlo updating process. The worm algorithm has a z comparable with the one of a cluster algorithm, but uses local updates only. We present results for the vacuum expectation value (φ) and for the two-point correlation function (φ(x)φ(x')> in the parameter space of the model, defined by the constants λand μ2. We determine the critical line λC, μC2)) that separates the symmetric and spontaneously-broken phases and compare with results of the literature. (author)

  13. Molecular basis for the blue bioluminescence of the Australian glow-worm Arachnocampa richardsae (Diptera: Keroplatidae).

    Science.gov (United States)

    Trowell, Stephen C; Dacres, Helen; Dumancic, Mira M; Leitch, Virginia; Rickards, Rodney W

    2016-09-16

    Bioluminescence is the emission of visible light by living organisms. Here we describe the isolation and characterisation of a cDNA encoding a MW ≈ 59,000 Da luciferase from the Australian glow-worm, Arachnocampa richardsae. The enzyme is a member of the acyl-CoA ligase superfamily and produces blue light on addition of D-luciferin. These results are contrary to earlier reports (Lee, J., Photochem Photobiol 24, 279-285 (1976), Viviani, V. R., Hastings, J. W. & Wilson, T., Photochem Photobiol 75, 22-27 (2002)), which suggested glow-worm luciferase has MW ≈ 36,000 Da and is unreactive with beetle luciferin. There are more than 2000 species of firefly, which all produce emissions from D-luciferin in the green to red regions of the electromagnetic spectrum. Although blue-emitting luciferases are known from marine organisms, they belong to different structural families and use a different substrate. The observation of blue emission from a D-luciferin-using enzyme is therefore unprecedented. PMID:27457804

  14. Radiation sensitivity and gene expression in Enchytraeus japonensis, a species of earth worm

    International Nuclear Information System (INIS)

    The importance of radiological protection of the environment based on scientific principles is gaining international recognition as environment issues garner more attention. Earthworm (annelids) is a ubiquitous soil invertebrate known to play an important role in the maintenance of the soil ecosystem and thus selected as one of 12 kinds of reference animals and plants by the ICRP. In the present study, radiation sensitivity and gene expression in a recently described terrestrial oligochaete, Enchytraeus japonensis (E. japonensis) were studied. E. japonensis worms were acutely irradiated at increasing doses of gamma radiation, and the number of worms after 30 days of radiation was examined. The dose effectively inhibiting 50% of proliferation was approximately 22 Gy, which was comparable to the dose required to elicit growth inhibition in other earthworm species. In order to seek other biological endpoints for more sensitive and/or quicker assessment of radiation effects, gene expression profiling in E. japonensis was also performed, and poly (ADP-ribose) polymerase I (PARP I) was identified as a radiation-responsive gene. PARP I transcript level increased dose-dependently. (author)

  15. Anthelminthic activity of Daniellia oliveri against Haemonchus contortus worms in Burkina Faso

    International Nuclear Information System (INIS)

    In the central region of the Burkina Faso, small holders like to use veterinary traditional practice to treat small ruminant gastro-intestinal parasitism. In this part of country, Daniellia oliveri plant is usually used against this disease. Aqueous decoction obtained from the stem barc of Daniellia oliveri was screened to determine his phytochemical composition and in vitro anthelminthic activity agains Haemonchus contortus adult worms. Results showed that the decoction lyophilized obtained is giving to small ruminant (25 kg) at the rate of 242.5 mg per body weight. In vitro anthelminthic revealed that Daniellia oliveri extract has significant effect (P < 0.05) on mortality or the paralysis of the adult worms of Haemonchus contortus compared to the control group. In fact, use of Daniellia oliveri leaves by pastoralist smallholders in traditional therapy against the gastro-intestinal small ruminant parasites is justified in the central region of the Burkina Faso. Therefore, the survey suggests to achieve other studies (phytochemical and toxicity) on Anogeissus leiocarpus leaves studied in order to develop a further drug antiparasitic subsequently

  16. Anthelminthic activity of Anogeissus leiocarpus against Haemonchus contortus worms in Burkina Faso

    International Nuclear Information System (INIS)

    Traditional Veterinary practice is current by pastoralist and small holders to treat small ruminant gastro-intestinal parasitism in the central region of the Burkina Faso. To treat these digestive pathologies, Anogeissus leiocarpus is usually used. Ethno-veterinary surveys have been achieved to understand the traditional use of Anogeissus leiocarpus and in vitro test has been carried out to value anthelminthic activity on the adult worms of Haemonchus contortus. Results showed that the plant part used are leaves and by oral way after decoction to obtain aqueous extract which is giving to small ruminant (25 kg) at the rate of 160 mg per body weight. In vitro anthelminthic activity test of aqueous extract of leaves revealed a significant effect (P < 0,05) on mortality or the paralysis of the adult worms of Haemonchus contortus compared to the control group (PBS). In fact, use of Anogeissus leiocarpus leaves by pastoralist and small holders in traditional therapy against the gastro-intestinal small ruminant parasites is justified in the central region of the Burkina Faso. Therefore, the survey suggests to achieve other pharmacologies and parasitologies studies on Anogeissus leiocarpus leaves in order to develop a further drug antiparasitic subsequently

  17. An externally brooding acorn worm (Hemichordata, Enteropneusta, Torquaratoridae) from the Russian arctic.

    Science.gov (United States)

    Osborn, Karen J; Gebruk, Andrey V; Rogacheva, Antonina; Holland, Nicholas D

    2013-10-01

    A single specimen of a previously undescribed acorn worm in the family Torquaratoridae was trawled from a bottom depth of about 350 m in the Kara Sea (Russian Arctic). The new species is the shallowest of the exclusively deep-sea torquaratorids found to date, possibly an example of high-latitude emergence. On the basis of ribosomal DNA sequences and morphology, the worm is described here as the holotype of Coleodesmium karaensis n. gen., n. sp. It is most similar in overall body shape to the previously described enteropneust genus Allapasus, but is uniquely characterized by a tubular component of the proboscis skeleton ensheathing the collar nerve cord. Additionally, within the proboscis, the sparseness of the musculature of C. karaensis clearly distinguishes it from the much more muscular members of Allapasus. The holotype is a female bearing about a dozen embryos on the surface of her pharyngeal region, each recessed within a shallow depression in the dorsal epidermis. The embryos, ranging from late gastrula to an early stage of coelom formation, are a little more than 1 mm in diameter and surrounded by a thin membrane. Each embryo comprises an external ectoderm of monociliated cells (not arranged in obvious ciliated bands) and an internal endo-mesoderm; the blastopore is closed. In the most advanced embryos, the anterior coelom is starting to constrict off from the archenteron. Coleodesmium karaensis is the first enteropneust (and indeed the first hemichordate) found brooding embryos on the surface of the mother's body. PMID:24243964

  18. Distribution and role of trace transition metals in Glycera worm jaws studied with synchrotron microbeam techniques

    International Nuclear Information System (INIS)

    A combination of position-resolved synchrotron microbeam techniques was used to explore the distribution and role of trace transition metals in the jaws of Glycera dibranchiata. The mandibles of this marine sediment worm have recently been found to be reinforced by the copper-based biomineral atacamite [Cu2(OH)3Cl]. Here we show that the system is more complex, containing zinc and iron and unmineralized copper compounds as well. X-ray absorption spectroscopy studies showed that a fraction of copper is present in oxidation state, Cu(I), in contrast to the mineral that exclusively contains Cu(II). X-ray fluorescence imaging revealed traces of copper also in the jaw base devoid of mineral. Traces of iron were found as well, but occurred spatially correlated with the copper mineral, suggesting a substitution of copper atoms by iron in the atacamite mineral. Zinc was evenly dispersed throughout the jaw matrix, quite in analogy to zinc in Nereis jaw, a related worm species, where nonmineralized zinc serves to cross-link and harden the proteinaceous matrix

  19. Distribution and role of trace transition metals in Glycera worm jaws studied with synchrotron microbeam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Lichtenegger, Helga C.; Birkedal, Henrik; Casa, Deigo M.; Cross, Julie O.; Heald, Steve M.; Waite, J. Herbert; Stucky, Galen

    2005-05-31

    A combination of position-resolved synchrotron microbeam techniques was used to explore the distribution and role of trace transition metals in the jaws of Glycera dibranchiata. The mandibles of this marine sediment worm have recently been found to be reinforced by the copper-based biomineral atacamite [Cu2(OH)3Cl]. Here we show that the system is more complex, containing zinc and iron and unmineralized copper compounds as well. X-ray absorption spectroscopy studies showed that a fraction of copper is present in oxidation state, Cu(I), in contrast to the mineral that exclusively contains Cu(II). X-ray fluorescence imaging revealed traces of copper also in the jaw base devoid of mineral. Traces of iron were found as well, but occurred spatially correlated with the copper mineral, suggesting a substitution of copper atoms by iron in the atacamite mineral. Zinc was evenly dispersed throughout the jaw matrix, quite in analogy to zinc in Nereis jaw, a related worm species, where nonmineralized zinc serves to cross-link and harden the proteinaceous matrix.

  20. Experimental Ascaris suum infection in the pig: protective memory response after three immunizations and effect of intestinal adult worm population

    DEFF Research Database (Denmark)

    Jungersen, Gregers; Eriksen, Lis; Roepstorff, Allan; Lind, Peter; Meeusen, E.N.T.; Rasmussen, Tina; Nansen, P.

    1999-01-01

    The protective immune response to larval migration in pigs, with or without adult intestinal worm populations, 10 weeks after 3 weekly Ascaris suum inoculations, was studied in 45 pigs. Controlled adult worm populations were achieved by oral transfer of 10 adult worms to previously immunized pigs...... after anthelmintic drenching. A significant reduction in larval recovery from lungs on day 7, and small intestine on day 14, was observed in immunized pigs compared with previously uninfected control pigs after challenge inoculation. The strong anamnestic response to larval migration was characterized...... inoculation or on the immune response before or after challenge inoculation could be detected. These results indicate that a significant protective memory immune response to A. suum challenge inoculation can be induced in pigs, and that this protective immunity is not significantly modulated by the presence...

  1. Preliminary effects of water hardness on triactinomyxon production and development from eastern tubifex worms infected with Myxobolus cerebralis

    Science.gov (United States)

    Waldrop, Thomas B.; Densmore, Christine; Blazer, Vicki; Smith, Dave; Schill, Bane

    1999-01-01

    Whirling disease is caused by Myxobolus cerebralis and requires an intermediate oligochaete host identified as Tubifex tubifex (Wolf, Markiw, and Hiltunen, 1986). M. cerebralis spores ingested by the tubifex worms develop into triactinomyxons (tams) that are eventually released into the water column to infect salmonid fish. There may be many environmental parameters, biotic or abiotic, that may affect the development of waterborne tams in eastern tubifex worms. This study will focus on one of those environmental parameters, total water hardness. Total water hardness is defined as the concentration of calcium and magnesium in a water sample expressed in milligrams per liter of equivalent CACO3 (Boyd, 1990). This study will address whether different levels of water hardness affect the development and production of tams released by infected tubifex worms.

  2. Disulfide-Based Diblock Copolymer Worm Gels: A Wholly-Synthetic Thermoreversible 3D Matrix for Sheet-Based Cultures

    OpenAIRE

    Simon, Karen Alambra; Warren, Nicholas J.; Mosadegh, Bobak; Mohammady, Marym R.; Whitesides, George McClelland; Armes, Steven P.

    2015-01-01

    It is well-known that 3D in vitro cell cultures provide a much better model than 2D cell cultures for understanding the in vivo microenvironment of cells. However, significant technical challenges in handling and analyzing 3D cell cultures remain, which currently limits their widespread application. Herein, we demonstrate the application of wholly synthetic thermoresponsive block copolymer worms in sheet-based 3D cell culture. These worms form a soft, free-standing gel reversibly at 20–37 °C,...

  3. Embryonation ability of Ascaridia galli eggs isolated from worm uteri or host faeces.

    Science.gov (United States)

    Rahimian, Shayan; Gauly, Matthias; Daş, Gürbüz

    2016-01-15

    Experimental infection models for Ascaridia galli rely on the use of eggs isolated either directly from worm uteri or from host faeces. We investigated whether A. galli eggs isolated from the two sources differ in their embryonation ability. A. galli eggs originating from 12 worm infrapopulations were isolated both from faeces of the living host (faecal eggs) and directly from worm uteri after host necropsy (uterine eggs). The isolated eggs from each infrapopulation and source were incubated in Petri dishes (n=24) containing a potassium-dichromate (0.1%) medium for 28 days (d) at room temperature. Starting from the day of egg isolation (d0), in ovo larval development was evaluated every second day by examining morphological characteristics of 200 eggs/petri dish. A total of 72,000 eggs were classified into undeveloped, early development, vermiform or fully embryonated stages. Isolation procedures caused similar damage to uterine and faecal eggs (2.2% and 0.5%, respectively; P=0.180). The first sign of in ovo embryonic development in faecal eggs (7%) was observed during the 24-h period when faeces were collected. On d28, a higher percentage of uterine eggs remained undeveloped when compared with faecal eggs (58.6% vs 11.0%; P<0.001). Although a higher (P<0.001) percentage of faecal eggs entered both the early developmental and vermiform stages, which took place primarily within the first two weeks of incubation, there was no time-shift between the development of faecal and uterine eggs. Starting from day 10, higher (P<0.05) percentages of faecal eggs completed embryonation compared with uterine equivalents. Eggs from both sources reached a plateau of embryonation by the end of 2nd week of incubation, with faecal eggs having a greater than two-fold higher embryonation ability. Cumulative mortality was higher in uterine eggs (14.3%) than in faecal eggs (0.2%). We conclude that faecal eggs have a higher embryonation ability than uterine eggs possibly due to maturation

  4. Worm control practice against gastro-intestinal parasites in Norwegian sheep and goat flocks

    Directory of Open Access Journals (Sweden)

    Vatn Synnøve

    2011-05-01

    Full Text Available Abstract Background Anthelmintic treatment is the most common way of controlling nematode infections in ruminants. However, several countries have reported anthelmintic resistance (AR, representing a limitation for sustainable small ruminant production. The knowledge regarding worm control management represents a baseline to develop a guideline for preventing AR. The aim of the present study was therefore to improve our knowledge about the worm control practices in small ruminant flocks in Norway. Methods A questionnaire survey regarding worm control practices was performed in small ruminant flocks in Norway. Flocks were selected from the three main areas of small ruminant farming, i.e. the coastal, inland and northern areas. A total of 825 questionnaires, comprising 587 sheep flocks (return rate of 51.3% and 238 goat flocks (52.6% were included. Results The results indicated that visual appraisal of individual weight was the most common means of estimating the anthelmintic dose used in sheep (78.6% and goat (85.1% flocks. The mean yearly drenching rate in lambs and ewes were 2.5 ± 1.7 and 1.9 ± 1.1, respectively, whereas it was 1.0 (once a year in goats. However, these figures were higher in sheep in the coastal area with a rate of 3.4 and 2.2 in lambs and ewes, respectively. Benzimidazoles were the predominant anthelmintic class used in sheep flocks (64.9% in 2007, whereas benzimidazoles and macrocyclic lactones were both equally used in dairy goat flocks. In the period of 2005-2007, 46.3% of the sheep flocks never changed the anthelmintic class. The dose and move strategy was practiced in 33.2% of the sheep flocks. Conclusions The present study showed that inaccurate weight calculation gives a risk of under-dosing in over 90% of the sheep and goat flocks in Norway. Taken together with a high treatment frequency in lambs, a lack of anthelmintic class rotation and the common use of a dose-and-move strategy, a real danger for development of

  5. Viability of microcomputed tomography to study tropical marine worm galleries in humid muddy sediments

    International Nuclear Information System (INIS)

    Bioturbation is an ecological process driven by organisms, which transports nutrients and gases from air/water to sediment through their galleries, by the time they feed, burrow and/or construct galleries. This exchange is vital to the maintenance of micro and macrobenthic organisms, mainly in muddy flat environments. Species with distinct galleries could create levels of bioturbation, affecting the benthic interactions. In this sense, it is fundamental developing a non-destructive method that permits identifying/quantifying the properties of these galleries. The recent advances in micro-computed tomography are allowing the high resolution 3D images generation. However, once muddy sediments are rich in organic matter and interstitial water, these would lead to motion artifacts which could, in turn, decrease the accuracy of galleries identification/quantification. In this context, the aim of this study was to develop a protocol which combines laboratory experiments and microtomography analysis in order to generate accurate 3D images of the small marine worm's galleries within humid muddy sediments. The sediment was collected at both muddy flats of Surui's and Itaipu lagoon's mangroves (RJ-Brazil), sieved (0.5mm mesh) and introduced with one individual of the marine worm Laeonereis acuta (Nereididae, Polychaeta) in each acrylic corer holders (4.4cm of internal diameter). High energy microtomography scanner was used to obtain 3D images and the setup calibration was 130 kV and 61 mA. Each acquisition image time was among 4h and 6h. Several procedures of drying remained water inside the cores were performed aiming obtaining images without movement artifacts due to circulating water, and this issue was one of the main studied parameter. In order to investigate possible chemical effects, 2ml of formalin (35%) with menthol were added to the surface of the cores. The results show that although the drying time was appropriated, the chemicals created bubbles within the

  6. Viability of microcomputed tomography to study tropical marine worm galleries in humid muddy sediments

    Energy Technology Data Exchange (ETDEWEB)

    Pennafirme, Simone F., E-mail: sipennafirme@gmail.com [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Biologia. Dept. de Biologia Marinha; Machado, Alessandra S.; Lima, Inaya; Suzuki, Katia N.; Lopes, Ricardo T., E-mail: machado@lin.ufrj.br, E-mail: inaya@lin.ufrj.br, E-mail: norisuzuki6@yahoo.com.br, E-mail: ricardo@lin.ufj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), RJ (Brazil). Lab. de Instrumentacao Nuclear

    2013-07-01

    Bioturbation is an ecological process driven by organisms, which transports nutrients and gases from air/water to sediment through their galleries, by the time they feed, burrow and/or construct galleries. This exchange is vital to the maintenance of micro and macrobenthic organisms, mainly in muddy flat environments. Species with distinct galleries could create levels of bioturbation, affecting the benthic interactions. In this sense, it is fundamental developing a non-destructive method that permits identifying/quantifying the properties of these galleries. The recent advances in micro-computed tomography are allowing the high resolution 3D images generation. However, once muddy sediments are rich in organic matter and interstitial water, these would lead to motion artifacts which could, in turn, decrease the accuracy of galleries identification/quantification. In this context, the aim of this study was to develop a protocol which combines laboratory experiments and microtomography analysis in order to generate accurate 3D images of the small marine worm's galleries within humid muddy sediments. The sediment was collected at both muddy flats of Surui's and Itaipu lagoon's mangroves (RJ-Brazil), sieved (0.5mm mesh) and introduced with one individual of the marine worm Laeonereis acuta (Nereididae, Polychaeta) in each acrylic corer holders (4.4cm of internal diameter). High energy microtomography scanner was used to obtain 3D images and the setup calibration was 130 kV and 61 mA. Each acquisition image time was among 4h and 6h. Several procedures of drying remained water inside the cores were performed aiming obtaining images without movement artifacts due to circulating water, and this issue was one of the main studied parameter. In order to investigate possible chemical effects, 2ml of formalin (35%) with menthol were added to the surface of the cores. The results show that although the drying time was appropriated, the chemicals created bubbles

  7. Bugs as drugs, part two: worms, leeches, scorpions, snails, ticks, centipedes, and spiders.

    Science.gov (United States)

    Cherniack, E Paul

    2011-03-01

    In this second of a two-part series analyzing the evidence for the use of organisms as medicine, the use of a number of different "bugs" (worms, leeches, snails, ticks, centipedes, and spiders) is detailed. Several live organisms are used as treatments: leeches for plastic surgery and osteoarthritis and the helminths Trichuris suis and Necator americanus for inflammatory bowel disease. Leech saliva is the source of a number of anticoagulants, including the antithrombin agent hirudin and its synthetic analogues, which have been approved for human use. Predatory arthropods, such as certain species of snails, spiders, scorpions, centipedes, and ticks provide a trove of potential analgesic peptides in their venom. A synthetic analogue of a snail venom peptide, ziconotide, has been approved for human use and is used as an alternative to opioids in severe pain cases. Arthropods, such as ticks, have venom that contains anticoagulants and centipede venom has a protein that corrects abnormalities in lipid metabolism. PMID:21438646

  8. Worm crawling inside my brain”: a rare case of delusional parasitosis

    Directory of Open Access Journals (Sweden)

    Sekh Afrar Alam

    2015-07-01

    Full Text Available Delusional parasitosis is a disorder in which persons suffering have a firm and unshakeable belief of harbouring some parasite or worm in his/her body. In today’s nosology, it has been placed under delusional disorder-somatic type in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5 (297.1 and under persistent delusional disorders in the tenth revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10 (F22. Existing literature has extensively described this condition to affect mainly the skin with some instances of affecting the oral mucosa and the intestine. We are reporting a rare case of delusional disorder of parasite infestation in the brain.

  9. Oscillation of the velvet worm slime jet by passive hydrodynamic instability.

    Science.gov (United States)

    Concha, Andrés; Mellado, Paula; Morera-Brenes, Bernal; Sampaio Costa, Cristiano; Mahadevan, L; Monge-Nájera, Julián

    2015-01-01

    The rapid squirt of a proteinaceous slime jet endows velvet worms (Onychophora) with a unique mechanism for defence from predators and for capturing prey by entangling them in a disordered web that immobilizes their target. However, to date, neither qualitative nor quantitative descriptions have been provided for this unique adaptation. Here we investigate the fast oscillatory motion of the oral papillae and the exiting liquid jet that oscillates with frequencies f~30-60 Hz. Using anatomical images, high-speed videography, theoretical analysis and a physical simulacrum, we show that this fast oscillatory motion is the result of an elastohydrodynamic instability driven by the interplay between the elasticity of oral papillae and the fast unsteady flow during squirting. Our results demonstrate how passive strategies can be cleverly harnessed by organisms, while suggesting future oscillating microfluidic devices, as well as novel ways for micro and nanofibre production using bioinspired strategies. PMID:25780995

  10. Prevalence of gastrointestinal round worms in calves in Sokoto, northwestern, Nigeria

    Directory of Open Access Journals (Sweden)

    Aliyu Mahmuda

    2012-10-01

    Full Text Available An investigation to determine the prevalence and distribution of gastrointestinal roundworms in calves in Sokoto metropolis was carried out. A total of 216 faecal samples from calves were examined using Modified McMaster technique for morphological egg differentiation and count of worm-egg per gram of faeces of the sampled calves. Positive samples were cultured to differentiate between morphologically indistinguishable nematode genera. An overall prevalence was found to be 133 (61.57%. Eight different nematode genera were identified with Cooperia spp being highest in prevalence (28.78% followed by Haemonchus spp (26.76% and the least was Toxocara spp (0.50%. The prevalence was generally higher in females (56.39% than in males (43.61%.

  11. Chemically programmed ink-jet printed resistive WORM memory array and readout circuit

    International Nuclear Information System (INIS)

    In this paper an ink-jet printed write once read many (WORM) resistive memory fabricated on paper substrate is presented. The memory elements are programmed for different resistance states by printing triethylene glycol monoethyl ether on the substrate before the actual memory element is printed using silver nano particle ink. The resistance is thus able to be set to a broad range of values without changing the geometry of the elements. A memory card consisting of 16 elements is manufactured for which the elements are each programmed to one of four defined logic levels, providing a total of 4294 967 296 unique possible combinations. Using a readout circuit, originally developed for resistive sensors to avoid crosstalk between elements, a memory card reader is manufactured that is able to read the values of the memory card and transfer the data to a PC. Such printed memory cards can be used in various applications. (paper)

  12. Counter-Rotatable Fan Gas Turbine Engine with Axial Flow Positive Displacement Worm Gas Generator

    Science.gov (United States)

    Giffin, Rollin George (Inventor); Murrow, Kurt David (Inventor); Fakunle, Oladapo (Inventor)

    2014-01-01

    A counter-rotatable fan turbine engine includes a counter-rotatable fan section, a worm gas generator, and a low pressure turbine to power the counter-rotatable fan section. The low pressure turbine maybe counter-rotatable or have a single direction of rotation in which case it powers the counter-rotatable fan section through a gearbox. The gas generator has inner and outer bodies having offset inner and outer axes extending through first, second, and third sections of a core assembly. At least one of the bodies is rotatable about its axis. The inner and outer bodies have intermeshed inner and outer helical blades wound about the inner and outer axes and extending radially outwardly and inwardly respectively. The helical blades have first, second, and third twist slopes in the first, second, and third sections respectively. A combustor section extends through at least a portion of the second section.

  13. Mass rearing the Old World screw-worm fly, Chrysomya bezziana

    International Nuclear Information System (INIS)

    Many countries within the tropics are afflicted with one of two species of screw-worm, either the New World screw-worm fly Cochliomyia hominivorax Coquerel (NWSWF), or the Old World screw-worm fly, Chrysomya bezziana Villenuve (OWSWF). In nature, larvae of both species are obligate parasites and feed on the living flesh of mammals and to a lesser extent, birds. Female flies lay eggs at the site of a pre-existing wound or near body orifices of the host. First instar larvae feed superficially on the wound; however, larger larvae use their hooked mouthparts to burrow deep into the flesh of the host. Damaged blood vessels provide a steady stream of blood and plasma that typically oozes from the infested wound. The wound also acquires a characteristic odour. Presumably, some of the volatile components emanating from the wound, also provide strong signals to gravid female flies, as once infested, wounds become far more attractive as a site to lay eggs than uninfested wounds. As the number of larvae increases, the myiasis enlarges and the well-being of the host is threatened. In areas where gravid female SWF are numerous, the wound has little chance to heal, thus death of the host is likely unless the wound is treated and re-infestation prevented. While New and Old World species are distantly related, they are remarkably similar ecologically and in their biological characteristics. Wherever either species occurs, it is considered a serious pest of livestock. Australia is fortunate that neither species of the screw-worm is present despite evidence that extensive areas appear environmentally suitable. The OWSWF is considered the most serious threat to Australia as it is present in the neighbouring countries of Papua New Guinea and Indonesia. It is envisaged that the sterile insect release method (SIRM) will be employed to eradicate the OWSWF if it becomes established in Australia. To facilitate such a programme, and to reduce delays in constructing a suitable mass rearing

  14. Economic impact of eradicating the New World screw-worm (Cochliomyia hominivorax) from Jamaica

    International Nuclear Information System (INIS)

    The purpose of the study is to assess the economic feasibility of eradicating the New World screw-worm (NWS), Cochliomyia hominivorax Coquerel, from Jamaica. The endemic presence of the NWS in Jamaica has caused the livestock sector to incur recurrent economic costs and losses. Eradication of the pest utilising the environmentally-benign sterile insect technique (SIT) has proved technologically feasible on other islands and other parts of the world. Based on these successful experiences, the proposed project to eradicate the NWS from Jamaica is expected to be similarly effective in eliminating the pest from Jamaica in a relatively short period of time. The elimination of the pest from the Caribbean would lessen the significant risk of re-infestation of eradicated areas and pest-free countries in the region

  15. Incidence of Old World screw-worm fly, Chrysomya bezziana in Iraq

    International Nuclear Information System (INIS)

    The Old World screw-worm fly (OWSWF), Chrysomya bezziana Villenuve, is a member of the insect family Calliphoridae and is an obligate parasite of warm-blooded animals in the tropics and sub-tropics (Norris and Murray 1964). Flies lay their eggs on the edge of wounds or body orifices; the resulting larvae invade the host tissues and produce lesions and infertility if the genitals become infested (Humphrey et al. 1980). Recorded hosts include cattle (Bos indicus), sheep (Ovis aries), goats (Caprus hircus), dogs (Canis familiaris), cats (Felis domesticus) and man (Homo sapiens) (Patton 1920, 1922, Stoddar and Peck 1962, Norris and Murray 1964). This investigation describes the incidence of myiasis caused by C. bezziana in Iraq from September 1996 to March 1998

  16. Insecticidal Activity of Some Plant Extracts Against Cotton Leaf Worm Spodoptera Littoralis (Boisd.)

    International Nuclear Information System (INIS)

    The present study aimed to investigate the toxic effect of some plant extracts on cotton leaf worm, Spodoptera littoralis (Boisd.). Petroleum ether was used as a solvent to extract effective components from some plants such as Terminalia arjuna, Erythrine caffra, Taxodium distichum and Melaleuca cajuputi. Treatment of 4th instar larvae with each of the four plant extracts caused clear mortality (25-57). The reduction in F1 progeny (1.5-44.1), elongation of the larval duration, and pupal period at any of the tested concentration were noticed (17-33). There was moderate gradient reduction in the pupation percentage of the different treatments (71) as compared to the control (93.3). Moderate fluctuation was observed among sex ratio (1:2.3). Percentages of adult emergence and growth were inhibited with increasing the concentrations as observed in four plant extracts (1.7) as compared to control (2.9)

  17. Oscillation of the velvet worm slime jet by passive hydrodynamic instability

    Science.gov (United States)

    Concha, Andrés; Mellado, Paula; Morera-Brenes, Bernal; Sampaio Costa, Cristiano; Mahadevan, L.; Monge-Nájera, Julián

    2015-03-01

    The rapid squirt of a proteinaceous slime jet endows velvet worms (Onychophora) with a unique mechanism for defence from predators and for capturing prey by entangling them in a disordered web that immobilizes their target. However, to date, neither qualitative nor quantitative descriptions have been provided for this unique adaptation. Here we investigate the fast oscillatory motion of the oral papillae and the exiting liquid jet that oscillates with frequencies f~30-60 Hz. Using anatomical images, high-speed videography, theoretical analysis and a physical simulacrum, we show that this fast oscillatory motion is the result of an elastohydrodynamic instability driven by the interplay between the elasticity of oral papillae and the fast unsteady flow during squirting. Our results demonstrate how passive strategies can be cleverly harnessed by organisms, while suggesting future oscillating microfluidic devices, as well as novel ways for micro and nanofibre production using bioinspired strategies.

  18. [Research on the cat stomach worm, Ollulanus tricuspis (Leuckart, 1865)--state of the art].

    Science.gov (United States)

    Hasslinger, M A

    1985-01-01

    The stomach worm of the cat with an unusual cycle has a special place among the nematodes. O. tricuspis can develop and breed endogen as well as exogen, the infection of other hosts with freedom of movement, takes place through the ingestion of vomitus material containing parasites. As the conventional coproscopic methods of routine diagnosis have failed, the examination of gastric mucus or gastric mucosal scrapings post mortem offers itself. Intra vitam a provocated vomitus or a gastric irrigation are the diagnostic methods of choice. Increased vomiting of unknown genesis should, however, evoke suspicion relating to an O. tricuspis-infection and suggest an examination of the material. Besides the cat, dog, pig, wild cat, fox, cheetah, lion and tiger act as natural or inadequate hosts. Pathological alterations or clinical symptoms are more obvious in unusual carriers of parasites. Therapeutically only Citarin 2,5% was convincing. PMID:3895570

  19. Low temperature industrial waste heat utilization in the area 'Speyer-Ludwigshafen-Frankenthal-Worms'

    International Nuclear Information System (INIS)

    The aim of the study is the elaboration of reliable facts whether and under which conditions low temperature industrial waste heat systems can be economically utilized for heating purposes. The source of the waste heat are power- and industrial plants. In order to obtain reliable results, investigations have been carried out in the area Speyer-Ludwigshafen-Frankenthal and Worms. These investigations showed a number of application possibilities for heat pumps and it became moreover evident that there is a high variaiton of the heat requirement due to social components and the different type of building structures of the consumers. The economic results showed that the application of this heating system can under certain conditions supplement resp. replace other heating systems. (orig.)

  20. Chemically programmed ink-jet printed resistive WORM memory array and readout circuit

    Science.gov (United States)

    Andersson, H.; Manuilskiy, A.; Sidén, J.; Gao, J.; Hummelgård, M.; Kunninmel, G. V.; Nilsson, H.-E.

    2014-09-01

    In this paper an ink-jet printed write once read many (WORM) resistive memory fabricated on paper substrate is presented. The memory elements are programmed for different resistance states by printing triethylene glycol monoethyl ether on the substrate before the actual memory element is printed using silver nano particle ink. The resistance is thus able to be set to a broad range of values without changing the geometry of the elements. A memory card consisting of 16 elements is manufactured for which the elements are each programmed to one of four defined logic levels, providing a total of 4294 967 296 unique possible combinations. Using a readout circuit, originally developed for resistive sensors to avoid crosstalk between elements, a memory card reader is manufactured that is able to read the values of the memory card and transfer the data to a PC. Such printed memory cards can be used in various applications.

  1. De novo assembly and characterization of the Trichuris trichiura adult worm transcriptome using Ion Torrent sequencing.

    Science.gov (United States)

    Santos, Leonardo N; Silva, Eduardo S; Santos, André S; De Sá, Pablo H; Ramos, Rommel T; Silva, Artur; Cooper, Philip J; Barreto, Maurício L; Loureiro, Sebastião; Pinheiro, Carina S; Alcantara-Neves, Neuza M; Pacheco, Luis G C

    2016-07-01

    Infection with helminthic parasites, including the soil-transmitted helminth Trichuris trichiura (human whipworm), has been shown to modulate host immune responses and, consequently, to have an impact on the development and manifestation of chronic human inflammatory diseases. De novo derivation of helminth proteomes from sequencing of transcriptomes will provide valuable data to aid identification of parasite proteins that could be evaluated as potential immunotherapeutic molecules in near future. Herein, we characterized the transcriptome of the adult stage of the human whipworm T. trichiura, using next-generation sequencing technology and a de novo assembly strategy. Nearly 17.6 million high-quality clean reads were assembled into 6414 contiguous sequences, with an N50 of 1606bp. In total, 5673 protein-encoding sequences were confidentially identified in the T. trichiura adult worm transcriptome; of these, 1013 sequences represent potential newly discovered proteins for the species, most of which presenting orthologs already annotated in the related species T. suis. A number of transcripts representing probable novel non-coding transcripts for the species T. trichiura were also identified. Among the most abundant transcripts, we found sequences that code for proteins involved in lipid transport, such as vitellogenins, and several chitin-binding proteins. Through a cross-species expression analysis of gene orthologs shared by T. trichiura and the closely related parasites T. suis and T. muris it was possible to find twenty-six protein-encoding genes that are consistently highly expressed in the adult stages of the three helminth species. Additionally, twenty transcripts could be identified that code for proteins previously detected by mass spectrometry analysis of protein fractions of the whipworm somatic extract that present immunomodulatory activities. Five of these transcripts were amongst the most highly expressed protein-encoding sequences in the T

  2. Characteristics and function of sulfur dioxygenase in Echiuran worm Urechis unicinctus.

    Directory of Open Access Journals (Sweden)

    Litao Zhang

    Full Text Available BACKGROUND: Sulfide is a common toxin to animals and is abundant in coastal and aquatic sediments. Sulfur dioxygenase (SDO is thought to be the key enzyme involved in sulfide oxidation in some organisms. The echiuran worm, Urechis unicinctus, inhabits coastal sediment and tolerates high concentrations of sulfide. The SDO is presumably important for sulfide tolerance in U. unicinctus. RESULTS: The full-length cDNA of SDO from the echiuran worm U. unicinctus, proven to be located in the mitochondria, was cloned and the analysis of its sequence suggests that it belongs to the metallo-β-lactamase superfamily. The enzyme was produced using an E. coli expression system and the measured activity is approximately 0.80 U mg protein(-1. Furthermore, the expression of four sub-segments of the U. unicinctus SDO was accomplished leading to preliminary identification of functional domains of the enzyme. The identification of the conserved metal I (H113, H115, H169 and D188, metal II (D117, H118, H169 and H229 as well as the potential glutathione (GSH (R197, Y231, M279 and I283 binding sites was determined by enzyme activity and GSH affinity measurements. The key residues responsible for SDO activity were identified by analysis of simultaneous mutations of residues D117 and H118 located close to the metal II binding site. CONCLUSION: The recombinant SDO from U. unicinctus was produced, purified and characterized. The metal binding sites in the SDO were identified and Y231 recognized as the mostly important amino acid residue for GSH binding. Our results show that SDO is located in the mitochondria where it plays an important role in sulfide detoxification of U. unicinctus.

  3. The Yoruba farm market as a communication channel in guinea worm disease surveillance.

    Science.gov (United States)

    Brieger, W R; Kendall, C

    1996-01-01

    Disease eradication programmes are by definition time bound and require strategies that facilitate timely intervention. Surveillance, which undergirds eradication, also requires timely strategies. Finding such strategies is especially challenging when the target disease is endemic in remote areas, e.g. guinea worm disease, the focus of this study. A strategy of market based surveillance was pilot tested in Ifeloju Local Government Area (LGA) of Oyo State, Nigeria. The project goal was to design a surveillance system that both fit into the natural communication network of rural people, and also enlisted their active involvement. Ethnographic research methods were employed to learn about market location, structure, catchment area and attendance pattern. Four larger farm markets (serving 164 hamlets with 17,000 population) were chosen. Each hamlet was visited and a volunteer 'reporter' was recruited. Reporters were trained on case recognition and detection, first aid and prevention, with a sensitivity to distinguishing indigenous and clinical perceptions of guinea worm. The market cycle was based on the traditional four-day week. Field workers visited every second market 16 times between October 1990 and February 1991. The reporter was expected to identify correctly the first case of the season and thus label the village as endemic for the season. Reporters gave oral reports, and positive indications were followed up within 48 hr by field workers, who verified the case and administered first aid. All hamlets were visited once a month to verify negative reports. Reporter attendance was monitored. Those who had a formal role in the market, e.g. sales agents, had better attendance than ordinary farmers who came only to sell their own produce. Knowledge of market structure and attender roles offers a guide for adapting this surveillance approach to other cultural systems and health issues. PMID:8928032

  4. Effects of water temperature and substrate type on spore production and release in eastern Tubifex tubifex worms infected with Myxobolus cerebralis

    Science.gov (United States)

    Blazer, V.S.; Waldrop, T.B.; Schill, W.B.; Densmore, Christine L.; Smith, D.

    2003-01-01

    Eastern Tubifex tubifex worms were exposed to Myxobolus cerebralis spores at 9, 13, 17, and 20 C in 1-L jars that contained sand, mud, or leaf litter as substrata. Beginning 60 days after exposure, water from each jar was filtered daily and examined for the presence of waterborne triactinomyxon spores (TAMs). On discovering a single TAM from an experimental jar, 48 T. tubifex worms from that jar were placed individually into 24-well plates. Spores released from individual infected T. tubifex worms were quantified to determine the first day of TAM release from infected worms, the infection rate, the total number of TAMs released per worm, and the duration of release. No TAMs were found in any of the jars incubated at 20 C or in uninfected, control worms at any temperature. The total number of TAMs released by infected worms in mud and sand was highest at 13 C compared with other temperatures. Infection rates among individual worms increased with temperature between 9 and 17 C. Higher temperatures (up to 17 C) induced earlier TAM releases among infected worms, and substratum did not influence this production parameter. The average duration of TAM release decreased as the temperature increased from 9 to 17 C, and there was a significant effect of substratum in the groups maintained at 13 and 17 C. In all temperature treatments between 9 and 17 C, the duration of release was least in the worms maintained in leaf litter, as was the total number of TAMs released during the experimental period and the median number of TAMs per production day.

  5. Failure analysis of the worm gear of the actuator of the motor-valve 2-N71-MV-1867

    International Nuclear Information System (INIS)

    In this work the results of the tests realized to the worm gear of the actuator of the motor-valve type butterfly 2-N71-MV-1867 coming from the nuclear power plant of Laguna Verde area presented, to determine the failure mechanism that caused the fracture of two of their wires. These wires present a lines model of irregular contact, what suggests the existence of non alignment in the gear-wheel system. The chemical analysis by means of optical emission spectrophotometry showed that the worm gear was manufactured starting from steel grade machinery AISI 4320H. The metallographic analysis corroborated that the chord of the worm gear was hardened superficially by means of a thermochemistry treatment of cemented, reaching a maximum hardness of cemented layer in the contact area of 58 HRC and a thickness of effective layer of 1.2 mm, also the presence of carbides precipitated in grain limits in the cemented layer was found, that which is not desirable because this increases its fragility. Likewise in the nucleus a tempering structure too much soft was revealed, 22 HRC. The analysis of the extracted fracture surfaces of the cracked areas during the operation of the worm gear, they suggest that the fracture mechanism was the fatigue of the material, which was generated starting from an em brittle cemented surface and it is spread inside a nucleus of low mechanical resistance. (Author)

  6. Disulfide-Based Diblock Copolymer Worm Gels: A Wholly-Synthetic Thermoreversible 3D Matrix for Sheet-Based Cultures.

    Science.gov (United States)

    Simon, Karen A; Warren, Nicholas J; Mosadegh, Bobak; Mohammady, Marym R; Whitesides, George M; Armes, Steven P

    2015-12-14

    It is well-known that 3D in vitro cell cultures provide a much better model than 2D cell cultures for understanding the in vivo microenvironment of cells. However, significant technical challenges in handling and analyzing 3D cell cultures remain, which currently limits their widespread application. Herein, we demonstrate the application of wholly synthetic thermoresponsive block copolymer worms in sheet-based 3D cell culture. These worms form a soft, free-standing gel reversibly at 20-37 °C, which can be rapidly converted into a free-flowing dispersion of spheres on cooling to 5 °C. Functionalization of the worms with disulfide groups was found to be essential for ensuring sufficient mechanical stability of these hydrogels to enable long-term cell culture. These disulfide groups are conveniently introduced via statistical copolymerization of a disulfide-based dimethacrylate under conditions that favor intramolecular cyclization and subsequent thiol/disulfide exchange leads to the formation of reversible covalent bonds between adjacent worms within the gel. This new approach enables cells to be embedded within micrometer-thick slabs of gel with good viability, permits cell culture for at least 12 days, and facilitates recovery of viable cells from the gel simply by incubating the culture in buffer at 4 °C (thus, avoiding the enzymatic degradation required for cell harvesting when using commercial protein-based gels, such as Matrigel). PMID:26509930

  7. Accumulation of polycyclic aromatic hydrocarbons from creosote-contaminated soil in selected plants and the oligochaete worm Enchytraeus crypticus

    Energy Technology Data Exchange (ETDEWEB)

    Ann-Sofie Allard; Marianne Malmberg; Alasdair H. Neilson; Mikael Remberger [IVL, Stockholm (Sweden). Swedish Environmental Research Institute

    2005-07-01

    The accumulation of PAHs from a creosote-contaminated soil was examined in laboratory experiments using English ryegrass (Lolium perenne), white clover (Trifolium repens) and radish (Raphanus sativus), and the oligochaete worm Enchytraeus crypticus. Toxicity to the plants and the worms was assessed, and a soil sample mixed with calcined sand was used for accumulation experiments to avoid interference from toxicity in the soil. Accumulation of potentially carcinogenic PAHs varied among the plants, and there was a linear relation between concentrations of PAHs in the soil and in the plants. Correlations between values of the biota-soil accumulation factors and octanol-water partition coefficients, or water solubility varied among the plants and were rather weak, so that lipophilic character or water solubility of the PAHs alone cannot explain PAH accumulation. Accumulation of carcinogenic PAHs from the soil, in the presence of the other PAHs was greatest for Trifolium repens. PAHs were accumulated in the oligochaete worm (Enchytraeus crypticus), and biota-soil accumulation factors exceeded those for the plants. It is suggested that site-specific evaluation of contaminated sites should include not only chemical analysis and evaluation of toxicity but also accumulation of contaminants into biota such as plants and worms.

  8. Influence of zinc nanoparticles on survival of worms Eisenia fetida and taxonomic diversity of the gut microflora.

    Science.gov (United States)

    Yausheva, Еlena; Sizova, Еlena; Lebedev, Svyatoslav; Skalny, Anatoliy; Miroshnikov, Sergey; Plotnikov, Andrey; Khlopko, Yuri; Gogoleva, Natalia; Cherkasov, Sergey

    2016-07-01

    The study was conducted to examine the effect of zinc nanoparticles on survival of worms Eisenia fetida and composition of the gut microflora. Analysis of the survival data has shown that the introduction of high doses of the nanoparticles causes death of worms in the second group with 35 % mortality rate and activates protective mechanisms realized as mucous film. DNA from the worm guts was extracted and 16S metagenomic sequencing was fulfilled using MiSeq (Illumina). Regarding the gut microflora of worms in the control group, high diversity of microorganisms (303 OTUs) was noted. Most of those belong to the taxa Firmicutes (51.9 % of the total high-quality united reads), Proteobacteria (24.1 % of the total), and Actinobacteria (13.3 % of the total), which were represented by numerous species of gen. Clostridium (C. saccharobutylicum, C. saccharoperbutylacetonicum, C. beijerinckii), gen. Pseudomonas (P. hydrogenovora, P. aeruginosa, and P. putida), gen. Bacillus (B. megaterium, B. silvestris), gen. Cellulomonas (B. megaterium, B. silvestris), and other numerically smaller genera. Adding of zinc nanoparticles to the substrate decreased the diversity of bacteria (78 OTUs) as well as percentage of bacteria belonging to the taxon Firmicutes (-41.6 %) and increased the proportion of Proteobacteria due to growth in abundance of gen. Verminephrobacter (+46 %) and gen. Ochrobactrum (+19.5 %). PMID:27023811

  9. Development of a chronic sublethal bioassay for evaluating contaminated sediment with the marine polychaete worm Nereis (Neanthes) arenaceodentata

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, T.M.; Moore, D.W.; Gibson, A.B. (Army Engineer Waterways Experiment Station, Vicksburg, MS (United States))

    1993-03-01

    Development of a chronic sublethal sediment bioassay with the polychaete Nereis (Neanthes) arenaceodentata is described. The sublethal test end point was estimated individual somatic growth rate. The test was initiated with two-to three-week-old post-emergent juvenile worms and continued for 28 d. The potential bias due to selected nontreatment factors on polychaete survival and growth was evaluated. For example, grain size has no significant effect, whereas the number of worms placed in each exposure vessel was critical. Direct transfer from 30[per thousand] seawater to salinites [<=] 15[per thousand] had a highly significant and adverse effect on survival and growth. Both survival and growth of juvenile worms may be adversely affected if test conditions involve exposures to [>=] 0.7 mg/L un-ionized ammonia or [>=] 5 mg/L hydrogen sulfide. Survival of juvenile worms to concentrations of the reference toxicant, cadmium chloride, approximating the 96-h LC50 (5 mg/L) was used as a quality control measure. Results are expressed in control chart format analogous to methods used in analytical chemistry.

  10. Gamma- and epsilonproteobacterial ectosymbionts of a shallow-water marine worm are related to deep-sea hydrothermal vent ectosymbionts.

    Science.gov (United States)

    Ruehland, Caroline; Dubilier, Nicole

    2010-08-01

    The marine oligochaete worm Tubificoides benedii is often found in high numbers in eutrophic coastal sediments with low oxygen and high sulfide concentrations. A dense biofilm of filamentous bacteria on the worm's tail end were morphologically described over 20 years ago, but no further studies of these epibiotic associations were done. In this study, we used fluorescence in situ hybridization and comparative sequence analysis of 16S rRNA and protein-coding genes to characterize the microbial community of the worm's tail ends. The presence of genes involved in chemoautotrophy (cbbL and cbbM) and sulfur metabolism (aprA) indicated the potential of the T. benedii microbial community for chemosynthesis. Two filamentous ectosymbionts were specific to the worm's tail ends: one belonged to the Leucothrix mucor clade within the Gammaproteobacteria and the other to the Thiovulgaceae within the Epsilonproteobacteria. Both T. benedii ectosymbionts belonged to clades that consisted almost exclusively of bacteria associated with invertebrates from deep-sea hydrothermal vents. Such close relationships between symbionts from shallow-water and deep-sea hosts that are not closely related to each other are unusual, and indicate that biogeography and host affiliation did not play a role in these associations. Instead, similarities between the dynamic environments of vents and organic-rich mudflats with their strong fluctuations in reductants and oxidants may have been the driving force behind the establishment and evolution of these symbioses. PMID:21966922

  11. Influence of tubificid worms on nutrient fluxes across water-sediment interface in fish farm settling ponds

    Directory of Open Access Journals (Sweden)

    Puigagut J.

    2014-04-01

    Full Text Available The influence of tubificid worms on nutrient translocation from water to fish farm sediments accumulating in settling ponds was addressed under laboratory conditions. Small microcosms of 0.5 L were filled up with 35 g of sludge from a fish farm settling pond and 0.15 L of filtered settling pond water. The experimental set up consisted of one control line (no worms added, a second experimental line with 1 mg of tubificid worms·g-1 fresh sediment (550 individuals·m-2 and a third experimental line with 40 mg of tubificid worms·g-1 fresh sediment (22 000 individuals·m-2. Nutrients translocation was determined by monitoring overlaying water concentration of ammonia, nitrate and phosphate for ten days. Results showed that abundances of 550 individuals·m-2 had no significant influence on the fluxes of nutrients here considered. However, the influence of higher abundances of tubificids (22 000 individuals·m-2 was of significant extent on the translocation of nitrate and phosphate. Accordingly, bioturbation of tubificids caused 55% lower nitrate uptake by the sediment when compared to control conditions. Phosphorus released by the sediments of the control condition was ca. 90% higher than that recorded under abundances of tubificids (22 000 individuals·m-2. Results obtained allowed us to estimate that fish farm settling ponds highly colonized by tubificid worms (22 000 individuals·m-2 may contribute to decrease phosphorus discharge (in terms of soluble phosphorus in ca. 5 g of P·ton-1 of fish produced.

  12. Improved Perceptions and Practices Related to Schistosomiasis and Intestinal Worm Infections Following PHAST Intervention on Kome Island, North-Western Tanzania.

    Science.gov (United States)

    Mwanga, Joseph R; Kaatano, Godfrey M; Siza, Julius E; Chang, Su Young; Ko, Yunsuk; Kullaya, Cyril M; Nsabo, Jackson; Eom, Keeseon S; Yong, Tai-Soon; Chai, Jong-Yil; Min, Duk-Young; Rim, Han-Jong; Changalucha, John M

    2015-10-01

    Schistosomiasis and intestinal worm infections are widespread diseases of public health importance in Tanzania. A study on perceptions and practices related to schistosomiasis and intestinal worm infections was undertaken among a community population of Kome Island in Sengerema District, north-western Tanzania, where intestinal schistosomiasis and intestinal worm infections are endemic. Schistosomiasis and intestinal worm-related perceptions and practices were assessed before and 3 years after implementation of a participatory hygiene and sanitation transformation (PHAST) intervention as a control measure. Data were obtained from baseline and post-intervention knowledge, attitudes, and practices (KAP) questionnaire surveys conducted twice in 2009 and 2012 among 82 individuals aged ≥15 years. We found significant increases in respondents' knowledge of the cause, transmission, symptoms, health consequences, and prevention of schistosomiasis and intestinal worm infections after PHAST intervention. The increase in respondents' knowledge on almost all aspects of the said infections was translated into actions to control schistosomiasis and intestinal worm infections. This has not been achieved by chance, but due to well-designed and locally-adapted PHAST intervention. We conclude that despite criticisms, PHAST approach is still useful in empowering communities to control water, sanitation, and hygiene related infectious diseases such as schistosomiasis and intestinal worm infections. PMID:26537035

  13. Human Schistosoma haematobium antifecundity immunity is dependent on transmission intensity and associated with immunoglobulin G1 to worm-derived antigens

    DEFF Research Database (Denmark)

    Wilson, Shona; Jones, Frances M.; van Dam, Govert J.;

    2014-01-01

    -worm-derived antigen. METHODS: For a Malian cohort (age, 5-29 years) residing in high-transmission fishing villages or a moderate-transmission village, worm fecundity was assessed using the ratio of urinary egg excretion to levels of circulating anodic antigen, a Schistosoma-specific antigen that is steadily secreted...... children, host age and transmission were negatively associated with worm fecundity. A significant interaction term between host age and transmission indicates that antifecundity immunity develops earlier in high-transmission areas. SWA immunoglobulin G1 (IgG1) levels explained the effect of transmission on...

  14. Combined effect of gamma radiation and some fungal control agents on the greasy cut- worm

    International Nuclear Information System (INIS)

    The greasy cut worm, Agrotis ipsilon (Lepidoptera- Noctuidae) is widely distributed all over the world, particularly in moderate and subtropical countries of the northern and southern hemispheres (Kononenko ,2003). The greasy cut worm causes damage to vegetables, cucurbitaceous and industrial crops. The greatest damage is caused to cotton, essential-oil cultures, maize, tobacco, sunflower, tomatoes, sugar beet and potato. The pest can strongly harm vegetables, and also damage seedlings of tree species (pine, maple, and nut). This pest has solitary habits. They commonly feed on seedlings at ground level, cutting off the stem and sometimes dragging the plants into their burrows. The continuous use of chemical pesticides against pests, resistance to the action of pesticides had dramatically evolved. Also, the extensive use of these chemicals has given rise to problems such as residual toxicity (pollution) and harmful effects on beneficial insects, which are natural enemies of target or nontarget pest species. Such problems have become a cause of search for safety pesticides including microbial agents as fungi, bacteria and viruses (Rashed, 1993). The use of radiation to induce dominate lethal mutations in the sterile insect technique (SIT) is now as the major component of many large and successful programs for pest suppression and eradication. Adult insects, and their different developmental stages, differ in their sensitivity to the induction of dominate lethal mutation. Care has to be taken to identify the appropriate dose of radiation that produces the required level of sterility without impairing the overall fitness of the released insects.(Sawires, 2005). This technique would be successful control device for suppressing and combating many lepidopteraus insect pests, including A. Ipsilon has been studied (EL- kady et al., 1983, EL-Naggar et al., 1984, Abd El -Hamid 2004 and Gabarty, 2008). Entomopathogenic fungi that infect insects have received considerable

  15. The Pathogenicity of Bio-Insecticide Protecto to Gamma Irradiated Cotton Leaf Worm Spodoptera littoralis (Boisd.)

    International Nuclear Information System (INIS)

    Toxicological study using commercial formulation of Protecto based on the entomopathogenic bacterium Bacillus thuringiensis var kurstaki (B.t) in concentrations ranging from 0.09 to 10% were carried out versus second and fourth larval instar of the cotton leaf worm Spodoptera littoralis (Boisd.). The different pathological and biological aspects as larval and pupal mortality and developmental periods obviously increased by concentration increment, where the maximum mortality percentage, 91.66%, was observed when a concentration of 10% was used against the second instar. The longest developmental period, 29.1 days, was obtained when a concentration of 10% was applied against the second instar while it was 24.88 days when the same concentration was applied against the fourth instar. The pupation percentage, adult emergence percentage, survival percentage and adult longevity almost decreased by concentration increase where the least pupation and adult emergence percentage of second larval instar were observed at a concentration of 10%, it was 18.33 and 45.45% respectively and survival percentage decreased to 8.33, 21.66% at both instars at the concentration of 10%. Also the adult female and male moth longevity decreased by increasing Bacterial concentration. LC50 was calculated for second and fourth instar. Two substerlizing doses of gamma radiation 175 and 125 Gy were applied to full grown male pupae and different mating aspects as mating percentage, fecundity, fertility, average number of spermatophores per mated female were calculated where the fecundity and fertility were significantly decreased among P1 and F1 generations compared to control. The second and fourth larval instar of the F1 generation of the two substerlizing doses were treated with LC50 of protecto and the different mating statuses were studied which indicated a clear decrease in fecundity and a significant decrease in fertility of females mated with treated males among P1 and F1 generations. The

  16. Agar Sediment Test for Assessing the Suitability of Organic Waste Streams for Recovering Nutrients by the Aquatic Worm Lumbriculus variegatus.

    Directory of Open Access Journals (Sweden)

    Bob Laarhoven

    Full Text Available An agar sediment test was developed to evaluate the suitability of organic waste streams from the food industry for recovering nutrients by the aquatic worm Lumbriculus variegatus (Lv. The effects of agar gel, sand, and food quantities in the sediment test on worm growth, reproduction, and water quality were studied. Agar gel addition ameliorated growth conditions by reducing food hydrolysis and altering sediment structure. Best results for combined reproduction and growth were obtained with 0.6% agar-gel (20 ml, 10 g. fine sand, 40 g. coarse sand, and 105 mg fish food (Tetramin. With agar gel, ingestion and growth is more the result of addition of food in its original quality. Final tests with secondary potato starch sludge and wheat bran demonstrated that this test is appropriate for the comparison of solid feedstuffs and suspended organic waste streams. This test method is expected to be suitable for organic waste studies using other sediment dwelling invertebrates.

  17. Distribution of the Common Adder Vipera berus and the Slow Worm Anguis fragils in Silesia, SW Poland

    Directory of Open Access Journals (Sweden)

    Kopij Grzezgorz

    2015-12-01

    Full Text Available During the years 2004-2008 the distribution of the Common Adder and the Slow Worm were studied in Silesia through questionnaire directed to forest inspectorates (n=871; 83.8% of them responded. These data were tested through field work in several randomly selected inspectorates. Both species were found to be widespread in the region, with a few strongholds identified in Sudety Mts. and larger forest complexes. The Common Adder was recorded in 68.5% of forest districts which responded, while the Slow Worm – in 73.6% of those districts. Changes in distribution and population trends could not be derived, since no reliable data were available from previous years.

  18. Parasites in Kentucky Thoroughbreds at necropsy: emphasis on stomach worms and tapeworms.

    Science.gov (United States)

    Lyons, E T; Tolliver, S C; Drudge, J H; Swerczek, T W; Crowe, M W

    1983-05-01

    A total of 363 Thoroughbreds (62 males, 292 females, and 9 geldings), 1 to 26 years of age, were examined at necropsy for internal parasites for about a 12-month period from February 1981 through February 1982. Emphasis was on examining the stomach for nematodes and the small intestine and cecum for tapeworms. Parasites recovered from the stomach and infection rates were: Habronema spp--immature (24%), H muscae--adult (38%), Draschia megastoma--immature (13%), D megastoma--adult (62%), and Trichostrongylus axei--adult (4%); lesions caused by D megastoma were found upon gross observation in 58% of the stomachs. The tapeworm, Anoplocephala perfoliata, was recovered from 54% of the horses; A magna was not found. There was no obvious difference in infection rates of the stomach worms and tapeworms according to age or sex of the horses. Seasonal differences were apparent only for immature Habronema spp and immature D megastoma for which infection rates began increasing in June, peaking in October, and declining thereafter. Presence of 4 additional species of parasites was recorded, but only a cursory examination was made for them. These were the large strongyles, Strongylus vulgaris, S edentatus, and S equinus, from the cecum and a filariid, Setaria spp (probably S equina), from the abdominal cavity, for which recovery rates from the horses were 8%, 8%, 1%, and 7%, respectively. PMID:6869991

  19. Synthesis of worm and chain-like nanoparticles by a microfluidic reactor process

    International Nuclear Information System (INIS)

    We demonstrate a room temperature microfluidic reactor (MFR) process for the synthesis of worm-like and chain-like shaped metallic nanoparticles (NPs). These high aspect ratio NPs are in geometrically metastable states, which can be further transformed into ellipsoidal, spherical, or short rod-like species with enhanced crystallinity after their solutions are stirred for several hours and/or undergo sonication for more than half an hour, evidenced by their transmission electron microscope (TEM) images, selected area electron diffraction (SAED), and X-ray Diffraction (XRD). Analysis on the relative stronger shape control ability by the microfluidic process than by the batch process suggests that the attachment and merging of pre-formed nanoclusters along the flow orientation in the microchannel slits may be the main reason for the formation of non-spherical shaped NPs. The result indicates that the room temperature microfluidic process has the potential to assemble primary nanoclusters into two-dimension architectures (i.e., chain-like networks).

  20. Interfacial behavior of resistive switching in ITO–PVK–Al WORM memory devices

    International Nuclear Information System (INIS)

    Understanding the mechanism of resistive switching in a memory device is fundamental in order to improve device performance. The mechanism of current switching in a basic organic write-once read-many (WORM) memory device is investigated by determining the energy level alignments of indium tin oxide (ITO), poly(9-vinylcarbazole) (PVK) and aluminum (Al) using x-ray and ultraviolet photoelectron spectroscopy, current–voltage characterization and Auger depth profiling. The current switching mechanism was determined to be controlled by the interface between the ITO and the PVK. The electric field applied across the device causes the ITO from the uneven surface of the anode to form metallic filaments through the PVK, causing a shorting effect within the device leading to increased conduction. This was found to be independent of the PVK thickness, although the switch-on voltage was non-linearly dependent on the thickness. The formation of these filaments also caused the destruction of the interfacial dipole at the PVK–Al interface. (paper)

  1. Development of the stomach worm, Obeliscoides cuniculi (Graybill), in lagomorphs, woodchucks and small rodents.

    Science.gov (United States)

    Measures, L N; Anderson, R C

    1983-07-01

    The parasitic development of Obeliscoides cuniculi multistriatus Measures and Anderson, 1983 was studied in New Zealand white rabbits (Oryctolagus cuniculus). Third-stage larvae exsheathed within 24 hr. The third molt occurred 3 days and the fourth 8-11 days post-infection. All worms were fifth stage 14 days post-infection. Males were mature at 16 days and copulation occurred in 15-16 days. Females were gravid at 18 days. The prepatent period was 16-22 days. The patent period was 61-118 days and males lived longer than females. All stages were found in the mucosa except the fifth which was found lying on the mucosal surface within a layer of mucus. Petechiae were the only lesions seen in experimentally infected rabbits. Patent infections of O. c. multistriatus were established experimentally in infected woodchucks (Marmota monax), snowshoe hares (Lepus americanus) and cottontail rabbits (Sylvilagus floridanus). Patent infections of O. c. cuniculi were established experimentally in snowshoe hares. Patent infections of O. c. multistriatus did not appear in experimentally infected HPB white (Swiss Webster) mice (Mus musculus). Wistar rats (Rattus norvegicus), H.O.R.F1 Syrian hamsters (Mesocricetus auratus), H.O.R.F1 smooth-haired guinea pigs (Cavia porcellus) and H.O.R.F1 gerbils (Meriones unguiculatus). PMID:6644921

  2. Potential effects of warmer worms and vectors on onchocerciasis transmission in West Africa.

    Science.gov (United States)

    Cheke, Robert A; Basáñez, Maria-Gloria; Perry, Malorie; White, Michael T; Garms, Rolf; Obuobie, Emmanuel; Lamberton, Poppy H L; Young, Stephen; Osei-Atweneboana, Mike Y; Intsiful, Joseph; Shen, Mingwang; Boakye, Daniel A; Wilson, Michael D

    2015-04-01

    Development times of eggs, larvae and pupae of vectors of onchocerciasis (Simulium spp.) and of Onchocerca volvulus larvae within the adult females of the vectors decrease with increasing temperature. At and above 25°C, the parasite could reach its infective stage in less than 7 days when vectors could transmit after only two gonotrophic cycles. After incorporating exponential functions for vector development into a novel blackfly population model, it was predicted that fly numbers in Liberia and Ghana would peak at air temperatures of 29°C and 34°C, about 3°C and 7°C above current monthly averages, respectively; parous rates of forest flies (Liberia) would peak at 29°C and of savannah flies (Ghana) at 30°C. Small temperature increases (less than 2°C) might lead to changes in geographical distributions of different vector taxa. When the new model was linked to an existing framework for the population dynamics of onchocerciasis in humans and vectors, transmission rates and worm loads were projected to increase with temperature to at least 33°C. By contrast, analyses of field data on forest flies in Liberia and savannah flies in Ghana, in relation to regional climate change predictions, suggested, on the basis of simple regressions, that 13-41% decreases in fly numbers would be expected between the present and before 2040. Further research is needed to reconcile these conflicting conclusions. PMID:25688018

  3. Christmas tree worms of Indo-Pacific coral reefs: untangling the Spirobranchus corniculatus (Grube, 1862) complex

    Science.gov (United States)

    Willette, Demian A.; Iñiguez, Abril R.; Kupriyanova, Elena K.; Starger, Craig J.; Varman, Tristan; Toha, Abdul Hamid; Maralit, Benedict A.; Barber, Paul H.

    2015-09-01

    Christmas tree worm is the common name of a group of colorful serpulid polychaetes from the genus Spirobranchus that are symbionts of hermatypic corals. As is increasingly common with reef-associated organisms, Spirobranchus is arranged as a complex of species with overlapping geographic ranges. Current species delimitations based largely on opercular morphology are problematic because of high intraspecific variation. Here, a multi-gene phylogeny of the Spirobranchus corniculatus complex, which tentatively includes S. corniculatus, S. cruciger, and S. gaymardi, sampled from the Coral Triangle, Australia, and Fiji, was reconstructed to test whether the complex includes three genetically distinct lineages identifiable by their opercula. Maximum-likelihood analyses of nuclear and mitochondrial markers revealed a single, monophyletic clade for the S. corniculatus complex. Furthermore, the genetic and morphological variation observed is not geographically based, indicating that the former S. corniculatus complex of three morphospecies is a single, morphologically variable species across the Central Indo-Pacific. Resolving the taxonomy of S. corniculatus presents novel opportunities to utilize this tentative bio-indicator species for monitoring reef health.

  4. Interfacial behavior of resistive switching in ITO-PVK-Al WORM memory devices

    Science.gov (United States)

    Whitcher, T. J.; Woon, K. L.; Wong, W. S.; Chanlek, N.; Nakajima, H.; Saisopa, T.; Songsiriritthigul, P.

    2016-02-01

    Understanding the mechanism of resistive switching in a memory device is fundamental in order to improve device performance. The mechanism of current switching in a basic organic write-once read-many (WORM) memory device is investigated by determining the energy level alignments of indium tin oxide (ITO), poly(9-vinylcarbazole) (PVK) and aluminum (Al) using x-ray and ultraviolet photoelectron spectroscopy, current-voltage characterization and Auger depth profiling. The current switching mechanism was determined to be controlled by the interface between the ITO and the PVK. The electric field applied across the device causes the ITO from the uneven surface of the anode to form metallic filaments through the PVK, causing a shorting effect within the device leading to increased conduction. This was found to be independent of the PVK thickness, although the switch-on voltage was non-linearly dependent on the thickness. The formation of these filaments also caused the destruction of the interfacial dipole at the PVK-Al interface.

  5. Vaccination with a cocktail of Ancylostoma ceylanicum recombinant antigens leads to worm burden reduction in hamsters.

    Science.gov (United States)

    Wiśniewski, Marcin; Łapiński, Maciej; Daniłowicz-Luebert, Emilia; Jaros, Sławomir; Długosz, Ewa; Wędrychowicz, Halina

    2016-09-01

    Hookworms, a group to which Ancylostoma ceylanicum belongs, are gastrointestinal nematodes that infect more than 700 million people around the world. They are a leading cause of anemia in developing countries. In order to effectively prevent hookworm infections research is conducted to develop an effective vaccine using recombinant antigens of the parasite. The aim of this study was to examine the influence of the hosts' on protection against ancylostomiasis and the shaping of the humoral immune response among Syrian hamsters after immunization with a cocktail of five A. ceylanicum recombinant antigens. Ace-ASP-3, Ace-ASP-4, Ace-APR-1, Ace-MEP-6 and Ace-MEP-7 were obtained in the pET expression system. Immunization with a vaccine cocktail resulted in a 33.5% worm burden reduction. The immunogenicity of the recombinant proteins were determined using ELISA. Statistical analysis showed that vaccinated hamsters developed stronger humoral responses to four of five recombinant antigens (the exception being Ace-ASP-3) compared to hamsters from the control group. PMID:27447220

  6. Peanut worms of the phylum Sipuncula from the Sea of Japan with a key to species

    Science.gov (United States)

    Maiorova, Anastassya S.; Adrianov, Andrey V.

    2013-02-01

    Sipunculan worms from the Russian waters of the Sea of Japan are still poorly investigated while they are much better known from the Japanese coast. The aim of this paper is to describe sipunculans from the Russian coast and from the deepest part of the Sea of Japan near the Primorye Province collected by SoJaBio expedition, and to provide keys for identification of sipunculan species from the Sea of Japan. At the Russian coast of the Sea of Japan only 8 valid species of sipunculans were found and identified: Golfingia margaritacea, G. vulgaris, Nephasoma capilleforme, N. wodjanizkii, Phascolion strombus, Thysanocardia nigra, Themiste hexadactyla (=T. pyroides), Phascolosoma agassizii. Taking into account 4 other valid species noted for this area, Nephasoma eremite, Thysanocardia catharinae, Themiste blanda and Phascolosoma scolops, which were not found, the sipunculan fauna of the Russian waters of the Sea of Japan now comprises 12 valid species. Nephasoma capilleforme and Nephasoma wodjanizkii are the first records for the North-West Pacific and the Sea of Japan. Species accounts include the most important taxonomic characters and specific biotope data. Accordingly, a key up to species level is provided. Totally, the fauna of the Sea of Japan is now estimated as having 31 valid species of sipunculans.

  7. Identification and characteristics of microRNAs from army worm, Spodoptera frugiperda cell line Sf21.

    Science.gov (United States)

    Kakumani, Pavan Kumar; Chinnappan, Mahendran; Singh, Ashok K; Malhotra, Pawan; Mukherjee, Sunil K; Bhatnagar, Raj K

    2015-01-01

    microRNAs play important regulatory role in all intrinsic cellular functions. Amongst lepidopteran insects, miRNAs from only Bombyx mori have been studied extensively with a little focus on Spodoptera sp. In the present study, we identified a total of 226 miRNAs from Spodoptera frugiperda cell line Sf21. Of the total, 116 miRNAs were well conserved within other insects, like B. mori, Drosophila melanogaster and Tribolium castenum while the remaining 110 miRNAs were identified as novel based on comparative analysis with the insect miRNA data set. Landscape distribution analysis based on Sf21 genome assembly revealed clustering of few novel miRNAs. A total of 5 miRNA clusters were identified and the largest one encodes 5 miRNA genes. In addition, 12 miRNAs were validated using northern blot analysis and putative functional role assignment for 6 Sf miRNAs was investigated by examining their relative abundance at different developmental stages of Spodoptera litura and body parts of 6th instar larvae. Further, we identified a total of 809 potential target genes with GO terms for selected miRNAs, involved in different metabolic and signalling pathways of the insect. The newly identified miRNAs greatly enrich the repertoire of insect miRNAs and analysis of expression profiles reveal their involvement at various steps of biochemical pathways of the army worm. PMID:25693181

  8. Schistosomicidal Activity of the Essential Oil of Ageratum conyzoides L. (Asteraceae against Adult Schistosoma mansoni Worms

    Directory of Open Access Journals (Sweden)

    Wilson R. Cunha

    2011-01-01

    Full Text Available The in vitro schistosomicidal effects of the essential oil of Ageratum conyzoides L. (Ac-EO against adult worms of Schistosoma mansoni is reported in this paper. Concerning this activity, Ac-EO was considered to be active, but less effective than the positive control (praziquantel, PZQ in terms of separation of coupled pairs, mortality, decrease in motor activity, and tegumental alterations. However, Ac-EO caused an interesting dose-dependent reduction in the number of eggs of S. mansoni. Precocene I (74.30% and (E-caryophyllene (14.23% were identified as the two major constituents of Ac-EO. These compounds were tested individually and were found to be much less effective than Ac-EO and PZQ. A mixture of the two major compounds in a ratio similar to that found in the Ac-EO was also less effective than Ac-EO, thus revealing that there are no synergistic effects between these components. These results suggest that the essential oil of A. conyzoides is very promising for the development of new schistosomicidal agents.

  9. Amino Acid Content of the Gamma Irradiated Cotton Leaf-Worm, Spodoptera Littoralis (Boisd.)

    International Nuclear Information System (INIS)

    The effects of gamma irradiation on amino acid content of the cotton leaf worm Spodoptera Littoralis was studied.The identified amino acids in the total body tissue of male moths were Theronine, Serine, Glutamic, Glycine, Alanine, Valine, Cystine, Methionine, Isoleucine, Leucine, Tyrosine, Phenylalanine, Lysine, Histidine and Arginine. The irradiation of full grown male pupae with doses 100,200 and 300 Gy decreased the total quantity of amino acids and the amount of most individual amino acids in male moths of P1 or F1 generations with some exceptions for Threonine, Alanine, Glycine, Serine, Valine, Cystine and Methionine which were increased.The effect of irradiation on amino acid content of the reproductive system tissues for each male or female were also studied.The results indicated that irradiation decreased the total quantity of amino acid content of both sexes by increasing the dose and males were more radiosensitive than females. Also, irradiation decreased the amount of individual amino acids in both sexes with certain exceptions, e.g. Alanine, Methionine and Tyrosine which increased in the reproductive system of male, and Methionine which increased by more than four times as control.The amino acid content was determined as well in F1 egg progeny, which was produced from irradiated males Irradiation doses (100, 200 and 300 Gy) decreased the total quantity of amino acids, and all individual ones except Cystine.The greatest reduction (54.9% was observed with Lysine at 300 Gy as compared to control

  10. THE E.U. TEXTILE AND CLOTHING TRADE AND ITS IMPACT ON SILK WORM REARING DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Agatha POPESCU

    2013-01-01

    Full Text Available The paper aimed to analyze the major trade flows in the E.U. textile and clothing industry in close connection with the future development of sericiculture using the data provided by EU Market Access Data Base for the period 2007-2011.The world market of textile and clothing is divided into two parts: raw material providers mainly situated in Asia, but also in South America and large processors situated in the E.U. such as Italy, France, United Kingdom and Spain, whose contribution to the EU production is 75 %. The main E.U. supplier of raw material for textile and clothing industry is China, followed by India, Bangladesh, Turkey and Brazil. About 33 % of the E.U.production of textile and garments is successfully exported as long as demand/offer ratio is unbalanced at world level. Import and export price have substantially increased. At present, the EU is the 2nd silk products exporter in the world. The new E.U. policy strategy regarding sericiculture is focused on the stimulation of silk worm rearing for producing cocoons mainly in Bulgaria, Greece, Italy, Spain, France and Romania where climate conditions are favorable, it is a long tradition in the field and rural population needs jobs. At the same time, the E.U. is focused on technology improvement and silk product design in order to create more value added and increase export and sales.

  11. Chronic toxicity of phenanthrene to the marine polychaete worm, Nereis (Neanthes) arenaceodentata

    Energy Technology Data Exchange (ETDEWEB)

    Emery, V.L. Jr.; Dillon, T.M. [USAE Waterways Experiment Station, Vicksburg, MS (United States)

    1996-02-01

    Polycyclic aromatic hydrocarbons (PAHs) are widely distributed in the environment. While environmental concentrations are generally below acutely, lethal levels, chronic, low level exposures may result in subtle sublethal effects. PAHs accumulate in bottom sediments and may represent a hazard to the benthos. Polychaetes are important members of this community. The objective of this study is to evaluate the chronic sublethal effects of one PAH, phenanthrene (PHN), on the polychaete worm, Nereis arenaceodentata. PHN was selected because of its high toxicity to marine invertebrates relative to other PAHs. The response of bivalves to heavy metals and other toxins has usually been determined by observing valve position. Since mussels close their valves to avoid noxious stimuli, experimental delivery of chemicals is uncertain. To obtain constant results. Preston employed plastic spacers to hold the valves apart. This obviates the observation of valve position as an index of response, and some other method is required. Electromyography of intact mussels is one such index, and is shown to be a simple, effective and quantitative measurement of activity. Experiments are reported on the effects of added mercury on salt water and fresh water species. Parts of this Nvork have appeared in brief form.

  12. Fabrication of worm-like Ag2S nanocrystals under mediation of protein

    Indian Academy of Sciences (India)

    Dezhi Qin; Li Zhang; Xian Du; Guangrui Yang; Qiuxia Zhang

    2015-10-01

    A simple protein-assisted method was reported to synthesize pepsin-conjugated Ag2S nanocrystals in aqueous solution. The morphology, composition and structure of the products were characterized by transmission electron microscopy, high-resolution transmission electron microscopy, energy-dispersive spectroscopy, selected area electron diffraction and X-ray diffraction measurements. The results showed that as-prepared monoclinic Ag2S nanocrystals are worm-like nanochains in shape with sizes about 25 nm in diameter and up to hundreds of nanometres in length. The multiple coordinate bonds of pepsin molecules to the surface of Ag2S nanocrystals make as-prepared samples have good colloidal stability and biocompatibility as elucidated by Fourier transform infrared examination. Thermogravimetry–differential scanning calorimetry analysis indicated that the obtained products are inorganic–organic nanocomposites and there is strong interaction between Ag2S and pepsin. This interaction could result in the change of hydrophilic environment of pepsin and consequently intrinsic fluorescence of protein was quenched by Ag2S nanocrystals. Furthermore, the nanochains assembly of particle–particle and rod–rod oriented attachment was discussed to investigate the growth mechanism.

  13. Synthesis of hierarchical worm-like SnO{sub 2}@C aggregates and their enhanced lithium storage properties

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zhen-Guo [School of Chemical Engineering, SichuanUniversity, Chengdu 610065 (China); College of Energy, Xiamen University, Xiamen 361005 (China); Li, Jun-Tao, E-mail: jtli@xmu.edu.cn [College of Energy, Xiamen University, Xiamen 361005 (China); Zhong, Yan-Jun [School of Chemical Engineering, SichuanUniversity, Chengdu 610065 (China); College of Energy, Xiamen University, Xiamen 361005 (China); Liu, Jie [State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Guo, Xiao-Dong, E-mail: xiaodong2009@163.com [School of Chemical Engineering, SichuanUniversity, Chengdu 610065 (China); Huang, Ling [State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Zhong, Ben-He [School of Chemical Engineering, SichuanUniversity, Chengdu 610065 (China); Sun, Shi-Gang [College of Energy, Xiamen University, Xiamen 361005 (China); State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China)

    2015-01-25

    Highlights: • The hierarchical worm-like SnO{sub 2}@C aggregates were synthesized. • The hierarchical worm-like SnO{sub 2}@C unit is assembled by nanowires. • The cycling performances of SnO{sub 2}@C aggregates are improved. • A capacity of 477.0 mA h g{sup −1} at 400 mA g{sup −1} could be obtained after 60 cycles. - Abstract: The present paper reports a synthetic strategy of hierarchical worm-like SnO{sub 2}@C aggregates with enhanced electrochemical performances. Specifically, a glucose-assisted hydrothermal treatment of the intermediate Co–Sn alloy nanoparticles, which were formed by carbothermal reduction of mixed commercial SnO{sub 2} and Co{sub 3}O{sub 4} nanoparticles. The SnO{sub 2}@C sample exhibits enhanced cycling performance in comparison with raw commercial SnO{sub 2} nanoparticles and intermediate Co–Sn alloy nanoparticles when used as anode of lithium ion battery. A stable capacity of 533.6 mA h g{sup −1} at 100 mA g{sup −1} and 477.0 mA h g{sup −1} at 400 mA g{sup −1} remains after 60 cycles. When the current density increases to 1600 mA g{sup −1}, the SnO{sub 2}@C sample still deliver a high capacity of 384.2 mA h g{sup −1}. The superior electrochemical performances could be attributed to the synergistic effect of unique worm-like aggregates structure and carbon surface-layer, which facilitate the electron transportation and buffer the large volume change.

  14. The Schistosoma mansoni Cytochrome P450 (CYP3050A1 Is Essential for Worm Survival and Egg Development.

    Directory of Open Access Journals (Sweden)

    Peter D Ziniel

    2015-12-01

    Full Text Available Schistosomiasis affects millions of people in developing countries and is responsible for more than 200,000 deaths annually. Because of toxicity and limited spectrum of activity of alternatives, there is effectively only one drug, praziquantel, available for its treatment. Recent data suggest that drug resistance could soon be a problem. There is therefore the need to identify new drug targets and develop drugs for the treatment of schistosomiasis. Analysis of the Schistosoma mansoni genome sequence for proteins involved in detoxification processes found that it encodes a single cytochrome P450 (CYP450 gene. Here we report that the 1452 bp open reading frame has a characteristic heme-binding region in its catalytic domain with a conserved heme ligating cysteine, a hydrophobic leader sequence present as the membrane interacting region, and overall structural conservation. The highest sequence identity to human CYP450s is 22%. Double stranded RNA (dsRNA silencing of S. mansoni (SmCYP450 in schistosomula results in worm death. Treating larval or adult worms with antifungal azole CYP450 inhibitors results in worm death at low micromolar concentrations. In addition, combinations of SmCYP450-specific dsRNA and miconazole show additive schistosomicidal effects supporting the hypothesis that SmCYP450 is the target of miconazole. Treatment of developing S. mansoni eggs with miconazole results in a dose dependent arrest in embryonic development. Our results indicate that SmCYP450 is essential for worm survival and egg development and validates it as a novel drug target. Preliminary structure-activity relationship suggests that the 1-(2,4-dichlorophenyl-2-(1H-imidazol-1-ylethan-1-ol moiety of miconazole is necessary for activity and that miconazole activity and selectivity could be improved by rational drug design.

  15. Comparison of worm development and host immune responses in natural hosts of schistosoma japonicum, yellow cattle and water buffalo

    OpenAIRE

    Yang Jianmei; Fu Zhiqiang; Feng Xingang; Shi Yaojun; Yuan Chunxiu; Liu Jinming; Hong Yang; Li Hao; Lu Ke; Lin Jiaojiao

    2012-01-01

    Abstract Background Yellow cattle and water buffalo are two of the most important natural hosts for Schistosoma japonicum in China. Previous observation has revealed that yellow cattle are more suited to the development of S. japonicum than water buffalo. Understanding more about the molecular mechanisms involved in worm development, as well as the pathological and immunological differences between yellow cattle and water buffalo post infection with S japonicum will provide useful information...

  16. Synthesis of hierarchical worm-like SnO2@C aggregates and their enhanced lithium storage properties

    International Nuclear Information System (INIS)

    Highlights: • The hierarchical worm-like SnO2@C aggregates were synthesized. • The hierarchical worm-like SnO2@C unit is assembled by nanowires. • The cycling performances of SnO2@C aggregates are improved. • A capacity of 477.0 mA h g−1 at 400 mA g−1 could be obtained after 60 cycles. - Abstract: The present paper reports a synthetic strategy of hierarchical worm-like SnO2@C aggregates with enhanced electrochemical performances. Specifically, a glucose-assisted hydrothermal treatment of the intermediate Co–Sn alloy nanoparticles, which were formed by carbothermal reduction of mixed commercial SnO2 and Co3O4 nanoparticles. The SnO2@C sample exhibits enhanced cycling performance in comparison with raw commercial SnO2 nanoparticles and intermediate Co–Sn alloy nanoparticles when used as anode of lithium ion battery. A stable capacity of 533.6 mA h g−1 at 100 mA g−1 and 477.0 mA h g−1 at 400 mA g−1 remains after 60 cycles. When the current density increases to 1600 mA g−1, the SnO2@C sample still deliver a high capacity of 384.2 mA h g−1. The superior electrochemical performances could be attributed to the synergistic effect of unique worm-like aggregates structure and carbon surface-layer, which facilitate the electron transportation and buffer the large volume change

  17. Reproductive biology, sexual dimorphism, and population structure of the deep sea hydrothermal vent scale-worm, Branchiplynoee seepensis (Polychaeta : Polynoidae)

    OpenAIRE

    Jollivet, D.; Empis, A; Baker, Mc; Hourdez, S; Comtet, Thierry; Jouin-toulmond, C; Desbruyeres, Daniel; Tyler, PA

    2000-01-01

    The polychaete family Polynoidae (scale-worms) is well-represented at deep sea hydrothermal vents. Most species are free-living in a wide range of habitats: from high-temperature hydrothermal `chimney' walls to diffuse venting areas. Conversely, species of the genus Branchipolynoe live inside the mantle cavity of vent and seep mytilids. Specimens, morphologically close to Branchipolynoe seepensis, have been reported from all the known vent areas on the Mid-Atlantic Ridge (MAR), with varying i...

  18. Effects of anti-allergic drugs on intestinal mastocytosis and worm expulsion of rats infected with Neodiplostomum seoulense

    OpenAIRE

    Shin, Eun-Hee; Kim, Tae-Heung; Hong, Sung-Jong; Park, Jae-Hwan; Guk, Sang-Mee; Chai, Jong-Yil

    2003-01-01

    The effects of anti-allergic drugs on intestinal mastocytosis and the expulsion of Neodiplostomum seoulense were observed in Sprague-Dawley rats, after oral infection with 500 metacercariae. The drugs used were hydroxyzine (a histamine receptor H1 blocker), cimetidine (a H2 blocker), cyclosporin-A (a helper T-cell suppressant), and prednisolone (a T- and B-cell suppressant). Infected, but untreated controls, and uninfected controls, were prepared. Worm recovery rate and intestinal mastocytosi...

  19. Establishment of Axial Properties in the Arrow Worm Embryo, Paraspadella gotoi (Chaetognatha): Developmental Fate of the First Two Blastomeres

    OpenAIRE

    Shimotori, Taishin; Goto, Taichiro

    1999-01-01

    Chaetognaths are bilateral animals totally symmetrical on both sides of their body. To elucidate the manner in which cell fates are established, single blastomeres of the two-cell stage embryos of the benthic arrow worm, Paraspadella gotoi, were injected with a fluorescent lineage-tracing dye. The distribution of labels was observed in the hatchlings by using a confocal laser scanning microscope. A total of four different labeling patterns was observed: 1) the dorsal epidermis, the right half...

  20. Barcoding of Arrow Worms (Phylum Chaetognatha) from Three Oceans: Genetic Diversity and Evolution within an Enigmatic Phylum

    OpenAIRE

    Robert M Jennings; Ann Bucklin; Annelies Pierrot-Bults

    2010-01-01

    Arrow worms (Phylum Chaetognatha) are abundant planktonic organisms and important predators in many food webs; yet, the classification and evolutionary relationships among chaetognath species remain poorly understood. A seemingly simple body plan is underlain by subtle variation in morphological details, obscuring the affinities of species within the phylum. Many species achieve near global distributions, spanning the same latitudinal bands in all ocean basins, while others present disjunct r...

  1. Deworming drugs for soil-transmitted intestinal worms in children: effects on nutritional indicators, haemoglobin, and school performance

    OpenAIRE

    David C Taylor-Robinson; Maayan, Nicola; Soares-Weiser, Karla; Donegan, Sarah; Garner, Paul

    2015-01-01

    Background The World Health Organization (WHO) recommends treating all school children at regular intervals with deworming drugs in areas where helminth infection is common. As the intervention is often claimed to have important health, nutrition, and societal effects beyond the removal of worms, we critically evaluated the evidence on benefits. Objectives To summarize the effects of giving deworming drugs to children to treat soil-transmitted helminths on weight, haemoglobin, and cognition; ...

  2. Characteristics of natural infections of the stomach worm, Obeliscoides cuniculi (Graybill), in lagomorphs and woodchucks in Canada.

    Science.gov (United States)

    Measures, L N; Anderson, R C

    1983-07-01

    Wild lagomorphs and woodchucks collected predominantly in southern Ontario, Canada were examined for subspecies of Obeliscoides cuniculi (Graybill). Obeliscoides cuniculi multistriatus was found in snowshoe hares (Lepus americanus). Obeliscoides cuniculi cuniculi was found in cottontail rabbits (Sylvilagus floridanus), European hares (Lepus capensis) and woodchucks (Marmota monax). Prevalence of Obeliscoides cuniculi multistriatus in snowshoe hares was 100% and mean intensity (and range of intensity) was 760 (9-4, 198) in Lindsay, Ontario in 1980. Mean intensity in hares varied trimonthly. The highest mean intensity of worms occurred in spring when most worms were adult. Transmission occurred mainly in spring. Most worms present in fall (70%) and winter (54%) were fourth stage. Immature fifth-stage and gravid females were present in hares during fall and winter. Prevalence and mean intensity of O. c. cuniculi in cottontails was 15% and 29 (1-118). Prevalence and mean intensity of O. c. cuniculi in woodchucks was 6% and 56 (16-118). European hares were infected with O. c. cuniculi, prevalence was 10% and mean intensity was 60 (36-83). In Ontario woodchucks and European hares were common in areas frequented by cottontail rabbits and probably acquired sporadic infections of O. c. cuniculi from infected cottontails. PMID:6644920

  3. Gastrointestinal parasitic worms in equines in the Paraíba Valley, State of São Paulo, Brazil.

    Science.gov (United States)

    Pereira, J R; Vianna, S S S

    2006-09-10

    Over a period of 12 years, from 1988 to 2000, a total of 20 individual equines (16 horses and 4 mules) were selected at random, from 10 municipalities in the Paraíba Valley, in the State of São Paulo, Brazil, and then subjected to necropsy for collection of gastrointestinal worms. Individual samples of 10% of the intestinal contents were also taken for counting and identifying the species present, and to establish the prevalence of worms in equine species in the Paraíba Valley. In the sample considered, the presence of parasites ranged from 155 to 1249 worms. Tapeworms (Cestoidea) were present in about 85% of the animals studied, and roundworms (Nematoda) in 100% of the individuals. All the tapeworms collected were of one single species, Anoplocephala perfoliata. In the case of the roundworms, the prevalence of individual species was: 100% for Cyathostomineae, 90% for Oxyuris equi, 70% for Strongylus vulgaris, 45% for S. edentatus, 15% for Strongylus equinus, 60% for Triodontophorus sp., 50% for Gyalocephalus capitatus, 15% for Oesophagodontus robustus and Craterostomum acuticaudatum, and 5% each for Parascaris equorum, Probstimayria vivipara, Habronema muscae, and Trichostrongylus axei. No specimens of flukes (Trematoda) were found in any of the animals studied. PMID:16687215

  4. Chromatographic Fingerprint Analysis and Effects of the Medicinal Plant Species Mitracarpus frigidus on Adult Schistosoma mansoni Worms

    Science.gov (United States)

    Fabri, Rodrigo Luiz; Aragão, Danielle Maria de Oliveira; Florêncio, Jônatas Rodrigues; Pinto, Nícolas de Castro Campos; Mattos, Ana Carolina Alves; Coelho, Paulo Marcos Zech; Castañon, Maria Christina Marques Nogueira; Vasconcelos, Eveline Gomes; Pinto, Priscila de Faria; Scio, Elita

    2014-01-01

    The aims of this work were to evaluate the in vitro and in vivo schistosomicidal properties of the methanolic extract of the aerial parts of Mitracarpus frigidus (MFM) and to determine its HPLC profile. For the in vitro experiment, four pairs of adult worms, obtained from infected mice, were exposed to different concentrations of MFM (100 to 400 μg/mL) for 24 and 48 h and analyzed under an inverted microscope. For the in vivo experiment, mice were inoculated with cercariae and, 20 days after infection, MFM (100 and 300 mg/kg) was administered orally for the following 25 days. Mice were euthanized after 60 days. MFM showed in vitro schistosomicidal activity, exhibiting the opening of the gynaecophoral canal of some male schistosomes, the presence of contorted muscles, vesicles, and the darkening of the paired worms skin. In vivo experiments showed that MFM treatments significantly reduced total worm count, as praziquantel, showing a decrease in liver and spleen weight. Also, a significant reduction in granuloma density was observed. MFM treatment did not cause alterations in the liver function of either infected or noninfected mice. The HPLC chromatogram profile showed the presence of kaempferol-O-rutinoside, rutin, kaempferol, psychorubrin, and ursolic acid. PMID:24901000

  5. Chromatographic Fingerprint Analysis and Effects of the Medicinal Plant Species Mitracarpus frigidus on Adult Schistosoma mansoni Worms

    Directory of Open Access Journals (Sweden)

    Rodrigo Luiz Fabri

    2014-01-01

    Full Text Available The aims of this work were to evaluate the in vitro and in vivo schistosomicidal properties of the methanolic extract of the aerial parts of Mitracarpus frigidus (MFM and to determine its HPLC profile. For the in vitro experiment, four pairs of adult worms, obtained from infected mice, were exposed to different concentrations of MFM (100 to 400 μg/mL for 24 and 48 h and analyzed under an inverted microscope. For the in vivo experiment, mice were inoculated with cercariae and, 20 days after infection, MFM (100 and 300 mg/kg was administered orally for the following 25 days. Mice were euthanized after 60 days. MFM showed in vitro schistosomicidal activity, exhibiting the opening of the gynaecophoral canal of some male schistosomes, the presence of contorted muscles, vesicles, and the darkening of the paired worms skin. In vivo experiments showed that MFM treatments significantly reduced total worm count, as praziquantel, showing a decrease in liver and spleen weight. Also, a significant reduction in granuloma density was observed. MFM treatment did not cause alterations in the liver function of either infected or noninfected mice. The HPLC chromatogram profile showed the presence of kaempferol-O-rutinoside, rutin, kaempferol, psychorubrin, and ursolic acid.

  6. Monitoring pollution in Tunisian coasts using a scale of classification based on biochemical markers in worms Nereis (Hediste) diversicolor.

    Science.gov (United States)

    Bouraoui, Zied; Banni, Mohamed; Chouba, Lassad; Ghedira, Jihen; Clerandeau, Cristelle; Jebali, Jamel; Narbonne, Jean Francois; Boussetta, Hamadi

    2010-05-01

    This paper aims to assess the marine environment quality along the Tunisian coasts using a statistical approach based on biomarkers response in the polychaete worms Nereis (Hediste) diversicolor. Worms were collected from six sites: Bizerta Lagoon, Gargour, Nakta, Mahres, Skhira and from Teboulba considered as a reference site. The biomarkers selected in this work were (1) the activities of cytochrome P450-dependent NADPH cytochrome c reductase (NADPH red) as phase I enzyme, (2) glutathione S-transferase as phase II enzyme and (3) the acetylcholinesterase activity as neurotoxicity marker. Oxidative stress was evaluated using catalase activity and malondialdehyde accumulation. For each biomarker, a discriminatory factor was calculated and a response index was allocated. For each site, a multi-marker pollution index was calculated as the sum of the response index of each of the five more discriminating biomarkers. The results show differences between sites compared with the reference samples. The multi-marker approach confirms that worms from Bizerta and Mahress have been submitted to highly polluted environment. Mahress shows the highest multi-marker pollution index, indicating a highly contamination status. PMID:19404756

  7. Worm control practices and anthelmintic usage in traditional and dairy cattle farms in the southern highlands of Tanzania.

    Science.gov (United States)

    Keyyu, J D; Kyvsgaard, N C; Kassuku, A A; Willingham, A L

    2003-05-15

    Worm control practices and anthelmintic usage in 177 cattle farms in Iringa district in the southern highlands of Tanzania was determined through a questionnaire survey. A total of 76 traditional, 92 small-scale dairy and 9 large-scale dairy cattle farms were included in the survey. Results indicated that 87.7% traditional, 97.8% small-scale dairy and 100% large-scale farmers relied solely on the use of anthelmintics, 2.7% traditional farmers used traditional medicines while 9.6% traditional farmers had not any form of worm control practice. Worm infection was ranked the second most important constraint of productivity in cattle in the three production systems. Most farms (57.6% traditional, 35.8% small-scale dairy, 66.7% large-scale dairy) used anthelmintics with a combination of levamisole and oxyclozanide. Benzimidazoles were used only in traditional (25.4%) and small-scale dairy (32.1%) farms while nitroxynil (Trodax) was mostly used in large-scale dairy farms (33.3%). Generally, 40% of farmers treated three or four times a year and the frequency in some farms was surprisingly high for resource poor small-scale farmers. The frequency of anthelmintic treatment was mostly the same regardless of the management system. Treatments in most farms depended on availability of money and drugs and not the epidemiology of parasites. A significant proportion (46.3%, P=0.007) of farmers especially in rural areas failed to follow their pre-planned treatment schedules due to lack of money (86%) and unavailability of drugs (6.6%). Many farmers (58.9%) had used the same type of anthelmintic for four or more consecutive years and 85.3% of them would continue with the same anthelmintic. Farmers in all management systems mostly purchased anthelmintics from private veterinary drug shops and about 43% traditional and 33.3% small-scale dairy farmers mostly in rural areas obtained anthelmintics from village extension officers. Despite the fact that all farmers were aware of worm

  8. Adhesive complex coacervate inspired by the sandcastle worm as a sealant for fetoscopic defects

    Science.gov (United States)

    Kaur, Sarbjit

    Inspired by the Sandcastle Worm, biomimetic of the water-borne adhesive was developed by complex coacervation of the synthetic copolyelectrolytes, mimicking the chemistries of the worm glue. The developed underwater adhesive was designed for sealing fetal membranes after fetoscopic surgery in twin-to-twin transfusion syndrome (TTTS) and sealing neural tissue of a fetus in aminiotic sac for spina bifida condition. Complex coacervate with increased bond strength was created by entrapping polyethylene glycol diacrylate (PEG-dA) monomer within the cross-linked coacervate network. Maximum shear bond strength of ~ 1.2 MPa on aluminum substrates was reached. The monomer-filled coacervate had complex flow behavior, thickening at low shear rates and then thinning suddenly with a 16-fold drop in viscosity at shear rates near 6 s-1. The microscale structure of the complex coacervates resembled a three-dimensional porous network of interconnected tubules. This complex coacervate adhesive was used in vitro studies to mimic the uterine wall-fetal membrane interface using a water column with one end and sealed with human fetal membranes and poultry breast, and a defect was created with an 11 French trocar. The coacervate adhesive in conjunction with the multiphase adhesive was used to seal the defect. The sealant withstood an additional traction of 12 g for 30-60 minutes and turbulence of the water column without leakage of fluid or slippage. The adhesive is nontoxic when in direct contact with human fetal membranes in an organ culture setting. A stable complex coacervate adhesive for long-term use in TTTS and spina bifida application was developed by methacrylating the copolyelectrolytes. The methacrylated coacervate was crosslinked chemically for TTTS and by photopolymerization for spina bifida. Tunable mechanical properties of the adhesive were achieved by varying the methacrylation of the polymers. Varying the amine to phosphate (A/P) ratio in the coacervate formation

  9. Excretory/secretory products from Trichinella spiralis adult worms ameliorate DSS-induced colitis in mice.

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    Xiaodi Yang

    Full Text Available BACKGROUND: Many evidences show the inverse correlation between helminth infection and allergic or autoimmune diseases. Identification and characterization of the active helminth-derived products responsible for the beneficial effects on allergic or inflammatory diseases will provide another feasible approach to treat these diseases. METHODS AND FINDINGS: Colitis was induced in C57BL/6 mice by giving 3% DSS orally for 7 days. During this period, the mice were treated daily with the excretory/secretory products from T. spiralis adult worms (AES intraperitoneally. The severity of colitis was monitored by measuring body weight, stool consistency or bleeding, colon length and inflammation. To determine the T. spiralis AES product-induced immunological response, Th1, Th2, Th17 and regulatory cytokine profiles were measured in lymphocytes isolated from colon, mesenteric lymph nodes (MLN, and the spleen of treated mice. The CD4+ CD25+ FOXP3+ regulatory T cells (Tregs were also measured in the spleens and MLN of treated mice. Mice treated with AES significantly ameliorated the severity of the DSS-induced colitis indicated by the reduced disease manifestations, improved macroscopic and microscopic inflammation correlated with the up-regulation of Treg response (increased regulatory cytokines IL-10, TGF-beta and regulatory T cells and down-regulation of pro-inflammatory cytokines (IFN-gamma, IL-6 and IL-17 in the spleens, MLN and colon of treated mice. CONCLUSIONS: Our results provide direct evidences that T. spiralis AES have a therapeutic potential for alleviating inflammatory colitis in mice. This effect is possibly mediated by the immunomodulation of regulatory T cells to produce regulatory and anti-inflammatory cytokines and inhibit pro-inflammatory cytokines.

  10. On the Temperature Behavior of Pulse Propagation and Relaxation in Worms, Nerves and Gels.

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    Christian Fillafer

    Full Text Available The effect of temperature on pulse propagation in biological systems has been an important field of research. Environmental temperature not only affects a host of physiological processes e.g. in poikilotherms but also provides an experimental means to investigate the thermodynamic phenomenology of nerves and muscle. In the present work, the temperature dependence of blood vessel pulsation velocity and frequency was studied in the annelid Lumbriculus variegatus. The pulse velocity was found to vary linearily between 0°C and 30°C. In contrast, the pulse frequency increased non-linearly in the same temperature range. A heat block ultimately resulted in complete cessation of vessel pulsations at 37.2±2.7°C (lowest: 33°C, highest: 43°C. However, quick cooling of the animal led to restoration of regularly propagating pulses. This experimentally observed phenomenology of pulse propagation and frequency is interpreted without any assumptions about molecules in the excitable membrane (e.g. ion channels or their temperature-dependent behaviour. By following Einstein's approach to thermodynamics and diffusion, a relation between relaxation time τ and compressibility κ of the excitable medium is derived that can be tested experimentally (for κT ∼ κS. Without fitting parameters this theory predicts the temperature dependence of the limiting (i.e. highest pulse frequency in good agreement with experimental data. The thermodynamic approach presented herein is neither limited to temperature nor to worms nor to living systems. It describes the coupling between pulse propagation and relaxation equally well in nerves and gels. The inherent consistency and universality of the concept underline its potential to explain the dependence of pulse propagation and relaxation on any thermodynamic observable.

  11. On the Temperature Behavior of Pulse Propagation and Relaxation in Worms, Nerves and Gels.

    Science.gov (United States)

    Fillafer, Christian; Schneider, Matthias F

    2013-01-01

    The effect of temperature on pulse propagation in biological systems has been an important field of research. Environmental temperature not only affects a host of physiological processes e.g. in poikilotherms but also provides an experimental means to investigate the thermodynamic phenomenology of nerves and muscle. In the present work, the temperature dependence of blood vessel pulsation velocity and frequency was studied in the annelid Lumbriculus variegatus. The pulse velocity was found to vary linearily between 0°C and 30°C. In contrast, the pulse frequency increased non-linearly in the same temperature range. A heat block ultimately resulted in complete cessation of vessel pulsations at 37.2±2.7°C (lowest: 33°C, highest: 43°C). However, quick cooling of the animal led to restoration of regularly propagating pulses. This experimentally observed phenomenology of pulse propagation and frequency is interpreted without any assumptions about molecules in the excitable membrane (e.g. ion channels) or their temperature-dependent behaviour. By following Einstein's approach to thermodynamics and diffusion, a relation between relaxation time τ and compressibility κ of the excitable medium is derived that can be tested experimentally (for κT ∼ κS). Without fitting parameters this theory predicts the temperature dependence of the limiting (i.e. highest) pulse frequency in good agreement with experimental data. The thermodynamic approach presented herein is neither limited to temperature nor to worms nor to living systems. It describes the coupling between pulse propagation and relaxation equally well in nerves and gels. The inherent consistency and universality of the concept underline its potential to explain the dependence of pulse propagation and relaxation on any thermodynamic observable. PMID:23805275

  12. Factors Affecting sex pheromone production in female cotton leaf worm moth, Spodoptera littoralis (boisd.)

    International Nuclear Information System (INIS)

    Factors influencing sex pheromone production in the cotton leaf worm female moth with emphasis on gamma radiation were investigated. To determine the effect of age on sex pheromone production, ether extracts of the female abdominal tips were prepared from virgin females of various ages in a concentration of 0.01 FE/mu L. Each female extract was tested against 1-2 days-old males. The obtained results indicated that virgin females could secrete sex pheromone early at the beginning of their life. The pheromone production increased rapidly to reach its maximum on the second day. To study the effect of daytime on sex pheromone production, the ether extracts of 1-2 days old virgin female abdominal tips were prepared at 3 hour-intervals, throughout the photo phase and scotophase in a concentration of 0.01 FE/mu L. The obtained results indicated that pheromone production showed a minimum concentration at mid-day during the photo phase. It then increased to a moderate concentration from 7:0 p.m. to 10:0 p.m. and reached its maximum titer at almost mid-night. The obtained data on the effect of gamma irradiation indicated that irradiation of 3 and 6-day-old female pupae with doses of 60 and 120 Gy, respectively caused a reduction of 28.1 and 27.3 % in male response, respectively, to female sex pheromone extracts. When full-grown female pupae were irradiated with 200 and 350 Gy, a reduction of 15.6 and 75% in male response, respectively, was reached. Thus, an irradiation dose of 350 Gy applied to full-grown female pupae could severely affect pheromone production of the emerging female moths

  13. "Tooth worms", poverty tattoos and dental care conflicts in Northeast Brazil.

    Science.gov (United States)

    Nations, Marilyn K; Nuto, Sharmêniade de Araújo Soares

    2002-01-01

    While medical anthropologists have studied doctor-patient clinical conflicts during the last 25-30 years, dentist-patient communication clashes have received scant attention to date. Besides structural barriers and power inequities, such conceptual differences further dehumanize dental care and lower service quality. Potential for dentist-patient discordance is greater in developing regions--such as Northeast Brazil--where there exists a wider socio-economic gap between professionals and laypersons. A critical anthropological evaluation of oral health services quality is undertaken in two rural communities in Ceará, Brazil where the PAHO-inspired Local Oral Health Inversion of Attention Program was implemented in 1994. This 6-month qualitative field study utilized ethnographic interviews with key informants, participant-observation and projective techniques to probe professionals' and patients' explanatory models (EMs) of oral health. Despite the recent expansion of services into rural regions, the authors conclude that the quality of dental care remains problematic. Patients' culturally constructed EMs of teeth rotted (estraga) by "tooth worms" (lagartas) differ substantively from dentists' model of dental decay by Streptococcus mutans. "Exploding chins" (queixo estourado), "spoiled, rotting teeth" (dente pĵdi) and "false plates" or teeth (chapas) tattoo and stigmatize the poor, reinforcing gross class inequities. Dentists' dominant discourse largely ignores lay logic, ridicules popular practices and de-legitimates, even castigates, popular healers despite their pivotal role in primary oral health care. Poor parents are not only barred from clinics but are blamed for children's rotten teeth. In sum, universal access to dental care is more a myth (even nightmare) than a reality. Dentists all too often "avert"--not "invert"--attention from poor Brazilian patients. In order to improve oral health in this setting, both "societal decay" and bacteria-laden plaque

  14. Parasitic worms: knowledge, attitudes, and practices in Western Cote d'Ivoire with implications for integrated control.

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    Cinthia A Acka

    Full Text Available BACKGROUND: In the developing world where parasitic worm infections are pervasive, preventive chemotherapy is the key strategy for morbidity control. However, local knowledge, attitudes, and practices (KAP of parasitic worms are poorly understood, although such information is required for prevention and sustainable control. METHODS: We carried out KAP surveys in two rural communities of Côte d'Ivoire that were subjected to school-based and community-based research and control activities. We used qualitative and quantitative methods. The former included observations, in-depth interviews with key informants, and focus group discussions with school children and adults. Quantitative methods consisted of a structured questionnaire administered to household heads. PRINCIPAL FINDINGS: Access to clean water was lacking in both communities and only a quarter of the households had functioning latrines. There was a better understanding of soil-transmitted helminthiasis than intestinal schistosomiasis, but community-based rather than school-based interventions appeared to improve knowledge of schistosomiasis. In the villages with community-based interventions, three-quarters of household interviewees knew about intestinal schistosomiasis compared to 14% in the village where school-based interventions were implemented (P<0.001. Whereas two-thirds of respondents from the community-based intervention village indicated that the research and control project was the main source of information, only a quarter of the respondents cited the project as the main source. CONCLUSIONS/SIGNIFICANCE: Preventive chemotherapy targeting school-aged children has limitations, as older population segments are neglected, and hence lack knowledge about how to prevent and control parasitic worm infections. Improved access to clean water and sanitation is necessary, along with health education to make a durable impact against helminth infections.

  15. Parasitic Worms: Knowledge, Attitudes, and Practices in Western Côte d’Ivoire with Implications for Integrated Control

    Science.gov (United States)

    Acka, Cinthia A.; Raso, Giovanna; N'Goran, Eliézer K.; Tschannen, Andres B.; Bogoch, Isaac I.; Séraphin, Essane; Tanner, Marcel; Obrist, Brigit; Utzinger, Jürg

    2010-01-01

    Background In the developing world where parasitic worm infections are pervasive, preventive chemotherapy is the key strategy for morbidity control. However, local knowledge, attitudes, and practices (KAP) of parasitic worms are poorly understood, although such information is required for prevention and sustainable control. Methods We carried out KAP surveys in two rural communities of Côte d'Ivoire that were subjected to school-based and community-based research and control activities. We used qualitative and quantitative methods. The former included observations, in-depth interviews with key informants, and focus group discussions with school children and adults. Quantitative methods consisted of a structured questionnaire administered to household heads. Principal Findings Access to clean water was lacking in both communities and only a quarter of the households had functioning latrines. There was a better understanding of soil-transmitted helminthiasis than intestinal schistosomiasis, but community-based rather than school-based interventions appeared to improve knowledge of schistosomiasis. In the villages with community-based interventions, three-quarters of household interviewees knew about intestinal schistosomiasis compared to 14% in the village where school-based interventions were implemented (P<0.001). Whereas two-thirds of respondents from the community-based intervention village indicated that the research and control project was the main source of information, only a quarter of the respondents cited the project as the main source. Conclusions/Significance Preventive chemotherapy targeting school-aged children has limitations, as older population segments are neglected, and hence lack knowledge about how to prevent and control parasitic worm infections. Improved access to clean water and sanitation is necessary, along with health education to make a durable impact against helminth infections. PMID:21200423

  16. [Anti-tumor effect of the whole worm extract of Ascaris lumbricoides on Lewis lung carcinoma in mice].

    Science.gov (United States)

    Yang, Xiao-Jun; Yang, Jun-Ping; Huang, Yan-Qin; Liang, Hua; Yuan, Keng

    2013-12-01

    Forty-five C57BL/6 mice were randomly divided into five groups (A-E). Group B and D served as the control group of A and C. Each mouse of group A was intraperitoneally injected with 0.1 ml whole worm extract of Ascaris lumbricoides every other day, and 10 days later injected with 0.1 ml Lewis lung carcinoma (LLC) cells at right axillary subcutaneously region. Mice of group B were injected with normal saline and then developed tumor model. Each mouse of group C was injected with 0.1 ml LLC cells, and two days later, injected with 0.1 ml whole worm extract of A. lumbricoides every other day for 5 times. After the tumor model developed, mice in group D were injected with normal saline. Group E was the negative control group. Time intervals between implantation and active growth and tumor weight were recorded. Tumor inhibition rate was calculated. The average time interval between tumor implantation and measurable tumor growth for groups A, B, C and D was (7.0 +/-1.1), (6.0 +/- 0.7), (9.0 +/- 1.2) and (7.0 +/- 0.9) days. Tumor weight of [(338.9 +/- 282.2) mg] (P inhibition rate group A [(722.2 +/- 413.5) mg] was heavier than that of group B was the highest in group C (33.3%). Tumor weight of group C [(237.8 +/- 101.8) mg] was lighter than that of group D [(356.7 +/- 176.9) mg] (P < 0.05). The results indicated that the tumor formation is affected by the whole worm extract of A. lumbricoides which may have an inhibitory effect on tumour growth. PMID:24818416

  17. Earthworm effects without earthworms: inoculation of raw organic matter with worm-worked substrates alters microbial community functioning.

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    Manuel Aira

    Full Text Available BACKGROUND: Earthworms are key organisms in organic matter decomposition because of the interactions they establish with soil microorganisms. They enhance decomposition rates through the joint action of direct effects (i.e. effects due to direct earthworm activity such as digestion, burrowing, etc and indirect effects (i.e. effects derived from earthworm activities such as cast ageing. Here we test whether indirect earthworm effects affect microbial community functioning in the substrate, as when earthworms are present (i. e., direct effects. METHODOLOGY/PRINCIPAL FINDINGS: To address these questions we inoculated fresh organic matter (pig manure with worm-worked substrates (vermicompost produced by three different earthworm species. Two doses of each vermicompost were used (2.5 and 10%. We hypothesized that the presence of worm-worked material in the fresh organic matter will result in an inoculum of different microorganisms and nutrients. This inoculum should interact with microbial communities in fresh organic matter, thus promoting modifications similar to those found when earthworms are present. Inoculation of worm-worked substrates provoked significant increases in microbial biomass and enzyme activities (β-glucosidase, cellulase, phosphatase and protease. These indirect effects were similar to, although lower than, those obtained in pig manure with earthworms (direct and indirect earthworm effects. In general, the effects were not dose-dependent, suggesting the existence of a threshold at which they were triggered. CONCLUSION/SIGNIFICANCE: Our data reveal that the relationships between earthworms and microorganisms are far from being understood, and suggest the existence of several positive feedbacks during earthworm activity as a result of the interactions between direct and indirect effects, since their combination produces stronger modifications to microbial biomass and enzyme activity.

  18. The use of FAMACHA in estimation of gastrointestinal nematodes and total worm burden in Damara and Barbados Blackbelly cross sheep.

    Science.gov (United States)

    Mohammed, Konto; Abba, Yusuf; Ramli, Nur Syairah Binti; Marimuthu, Murugaiyah; Omar, Mohammed Ariff; Abdullah, Faez Firdaus Jesse; Sadiq, Muhammad Abubakar; Tijjani, Abdulnasir; Chung, Eric Lim Teik; Lila, Mohammed Azmi Mohammed

    2016-06-01

    The prevalence of gastrointestinal (GI) nematodes and total worm burden of Damara and Barbados Blackbelly cross sheep was investigated among smallholder farms in Salak Tinggi district of Selangor, Malaysia. A total of 50 sheep raised in smallholder farms comprising of 27 Damara cross and 23 Barbados Blackbelly cross were categorized based on their age into young and adults. Fecal samples were collected and examined for strongyle egg count by using modified McMaster technique. Severity of infection was categorized into mild, moderate, and heavy, based on egg per gram (EPG). Five sheep were randomly selected and slaughtered to examine the presence of adult gastrointestinal (GI) nematodes through total worm count (TWC). Faffa Malan Chart (FAMACHA) score was used for investigation of worm load based on the degree of anemia. The study revealed an overall EPG prevalence of 88 %, of which 84.1 % had mild infection. There was a significant difference (p = 0.002) in EPG among the two breeds. Based on age, significant difference (p = 0. 004) in EPG was observed among Barbados Blackbelly cross, but not for Damara cross (p = 0.941). The correlation between severity of infection and the FAMACHA score was significant (r = 0.289; p = 0.042). Haemonchus spp. were the most predominant nematode found in the gastrointestinal tract, followed by Trichostrongylus and Oesophagostomum spps. EPG and TWC for Haemonchus were positively correlated, but not significant (r = 0.85, p = 0.066). From regression analysis, 73 % of the variability in TWC for Haemonchus could be explained by EPG. Thus, it can be concluded that FAMACHA score correlates well with severity of infection of a nematode and can be used to assess the strongyle nematode burden in the different sheep crosses. PMID:27038194

  19. Cadmium sulfide nanoparticles trigger DNA alterations and modify the bioturbation activity of tubificidae worms exposed through the sediment.

    Science.gov (United States)

    Dedeh, Amina; Ciutat, Aurélie; Lecroart, Pascal; Treguer-Delapierre, Mona; Bourdineaud, Jean-Paul

    2016-04-01

    To address the impact of cadmium sulfide nanoparticles (CdS NPs) in freshwater ecosystems, aquatic oligochaete Tubifex tubifex were exposed through the sediment to a low dose (0.52 mg of 8 nm in size of CdS NPs/kg) for 20 days using microcosms. Cadmium (Cd) was released from the CdS NPs-contaminated sediment to the water column, and during this period the average concentrations of Cd in the filtered water fraction were 0.026 ± 0.006 µg/L in presence of oligochaetes. Similar experiments with microparticular CdS and cadmium chloride (CdCl2) were simultaneously performed for comparative purposes. CdS NPs exposure triggered various effects on Tubifex worms compared to control, microsized and ionic reference, including modification of genome composition as assessed using RAPD-PCR genotoxicity tests. Bioaccumulation levels showed that CdS NPs were less bioavailable than CdCl2 to oligochaetes and reached 0.08 ± 0.01 µg Cd/g for CdS NPs exposure versus 0.76 ± 0.3 µg Cd/g for CdCl2 exposure (fresh weight). CdS NPs altered worm's behavior by decreasing significantly the bioturbation activity as assessed after the exposure period using conservative fluorescent particulate tracers. This study demonstrated the high potential harm of the CdS nanoparticular form despite its lower bioavailability for Tubifex worms. PMID:26618487

  20. Deep sequencing of New World screw-worm transcripts to discover genes involved in insecticide resistance

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    Azeredo-Espin Ana Maria L

    2010-12-01

    Full Text Available Abstract Background The New World screw-worm (NWS, Cochliomyia hominivorax, is one of the most important myiasis-causing flies, causing severe losses to the livestock industry. In its current geographical distribution, this species has been controlled by the application of insecticides, mainly organophosphate (OP compounds, but a number of lineages have been identified that are resistant to such chemicals. Despite its economic importance, only limited genetic information is available for the NWS. Here, as a part of an effort to characterize the C. hominivorax genome and identify putative genes involved in insecticide resistance, we sampled its transcriptome by deep sequencing of polyadenylated transcripts using the 454 sequencing technology. Results Deep sequencing on the 454 platform of three normalized libraries (larval, adult male and adult female generated a total of 548,940 reads. Eighteen candidate genes coding for three metabolic detoxification enzyme families, cytochrome P450 monooxygenases, glutathione S-transferases and carboxyl/cholinesterases were selected and gene expression levels were measured using quantitative real-time polymerase chain reaction (qRT-PCR. Of the investigated candidates, only one gene was expressed differently between control and resistant larvae with, at least, a 10-fold down-regulation in the resistant larvae. The presence of mutations in the acetylcholinesterase (target site and carboxylesterase E3 genes was investigated and all of the resistant flies presented E3 mutations previously associated with insecticide resistance. Conclusions Here, we provided the largest database of NWS expressed sequence tags that is an important resource, not only for further studies on the molecular basis of the OP resistance in NWS fly, but also for functional and comparative studies among Calliphoridae flies. Among our candidates, only one gene was found differentially expressed in resistant individuals, and its role on

  1. Midgut barrier imparts selective resistance to filarial worm infection in Culex pipiens pipiens.

    Directory of Open Access Journals (Sweden)

    Michelle L Michalski

    of these worms reveal compromised motility and sharp bends in the body; and ultrastructurally the presence of many fluid or carbohydrate-filled vacuoles in the hypodermis, body wall, and nuclear column. Incubation of Brugia mf with Cx. p. pipiens midgut extracts produces similar internal damage phenotypes; indicating that the Cx. p. pipiens midgut factor(s that damage mf in vivo are soluble and stable in physiological buffer, and inflict damage on mf in vitro.

  2. Fall in incidence of guinea-worm infection in western Nigeria after periodic treatment of infected persons

    OpenAIRE

    Kale, O. O.

    1982-01-01

    Between 1971 and 1974 a series of drug trials was conducted in 17 rural communities in western Nigeria where guinea-worm is endemic. During these trials and in subsequent years treatment, in the form of chemotherapy and/or dressing of ulcers, was given to all infected persons. A longitudinal study of infection in these villages showed a marked fall in the annual incidence over an 8-year period. The aggregate reduction in incidence in the three sectors surveyed was from 15.5% to 0.5% in sector...

  3. Histochemical demonstration of a rhodopsin-like substance in the eye of the arrow-worm, Spadella schizoptera (Chaetognatha).

    Science.gov (United States)

    Goto, T; Yoshida, M

    1988-01-01

    The presumed photoreceptive region of the arrow-worms of the species Sagitta crassa and Spadella schizoptera consists of perforated lamellae which are unique as the photoreceptive structure. The existence of a visual pigment in this region was demonstrated by a histofluorescent technique using Spadella schizoptera, whose presumed photoreceptive region was much larger than in Sagitta crassa. A specific fluorescence, indicative of the presence of retinal-based proteins, appeared only in the perforated lamellar region. The result suggests that the perforated lamellae contain a rhodopsin-like substance and could be the primary photoreceptive site. PMID:3268423

  4. The effect of gamma irradiation on the embryonic development of the cotton leaf worm spodoptera littoralis (Biosed.)

    International Nuclear Information System (INIS)

    The effect of gamma irradiation on the embryonic development of the cotton leaf worm studied. Irradiated eggs with 50 Gy gamma rays showed a high percentage of completely developed embryos and low hatch ability. The lowest percentages of embryonic development were obtained from the preparations of (I males)and (1 females)(irradiated males and irradiated females) matings which resulted from survived adults irradiated with 400 Gy (as full grown pupae). In case of eggs resulted from irradiated females mated with irradiated or non-irradiated males, a comparatively high percentages of incomplete embryonic development were noticed

  5. Study on Simulation Manufacturing of Mismatched Worm Gear%非对偶蜗轮蜗杆仿真加工的研究

    Institute of Scientific and Technical Information of China (English)

    杨文强; 王金尧

    2012-01-01

    The tooth profile of mismatched worm gear is complex and difficult to manufacture. A a system of the simulation manufacturing of mismatched worm gear is built based on SolidWorks with VB. When simulating manufacturing, the worm gear blank is fixed, the cutter is not only revolute around the axis of itself but also revolute around the axis of the worm gear, put the cutter in the different place, Boolean calculation of reduce between the enveloping solid of the cutter and the worm gear blank, the blank model is replace by the Boolean calculation. Because it is same that the expression of the model and part, the result about virtual manufacturing and the reality manufacturing is match. Assembling the worm wheel and worm, through the sectional view to observe the meshing condition of the worm wheel and worm, the manufacturing parameters are evaluated and adjusted.%非对偶蜗轮蜗杆的齿形复杂,加工难度大.以SolidWorks为平台,VB为开发工具,建立一个非对偶蜗轮蜗杆仿真加工系统.在模拟加工时,毛坯固定,刀具不仅绕其本身轴线旋转,同时还要绕毛坯轴线旋转,用多个刀具来模拟多个加工位置,刀具的运动所形成的包络体与毛坯进行实体布尔差运算,毛坯的三维模型随着布尔差运算过程被不断更新.而基于实体造型的方法中几何模型的表达与实际工件是一致的,使得仿真的最终结果与产品的实际加工结果相一致.将蜗轮和蜗杆进行装配,通过剖分成平面图的办法,来观察非对偶蜗轮蜗杆的啮合情况,以此来评价和调整蜗轮的加工参数.

  6. Heavy metal concentrations in two populations of Mopane worms (Imbrasia belina) in the Kruger National Park pose a potential human health risk.

    Science.gov (United States)

    Greenfield, R; Akala, N; van der Bank, F H

    2014-09-01

    Metal concentrations in Mopane worms from Phalaborwa and Shangoni sites in the Kruger National Park were determined. Metal concentrations were evaluated by inductively coupled plasma optical emission spectroscopy (ICP-OES) and ICP-MS spectrometry after microwave digestion. The results indicate a substantial bioaccumulation of metals in Mopane worms. In Phalaborwa Cd concentrations were 15 times and Cu two times higher than the EU and UK recommended legal limits for human consumption, Zn levels were tolerable. Likewise, Cd, Cu and Zn concentrations at the Shangoni site were 26, 2.5 and 0.4 times over the EU and UK approved limits. Manganese concentrations were 20 and 67 times higher than FDA standards respectively. During the study the condition factor of the worms was determined. No significant difference between the condition factors indicated the worms at both sites are in similar condition. Potential sources of metals in the worms are either from the food they eat or pollution settling on the leaves. PMID:24974173

  7. Dynamics of microbiological parameters, enzymatic activities and worm biomass production during vermicomposting of effluent treatment plant sludge of bakery industry.

    Science.gov (United States)

    Yadav, Anoop; Suthar, S; Garg, V K

    2015-10-01

    This paper reports the changes in microbial parameters and enzymatic activities during vermicomposting of effluent treatment plant sludge (ETPS) of bakery industry spiked with cow dung (CD) by Eisenia fetida. Six vermibins containing different ratios of ETPS and CD were maintained under controlled laboratory conditions for 15 weeks. Total bacterial and total fungal count increased upto 7th week and declined afterward in all the bins. Maximum bacterial and fungal count was 31.6 CFU × 10(6) g(-1) and 31 CFU × 10(4) g(-1) in 7th week. Maximum dehydrogenase activity was 1921 μg TPF g(-1) h(-1) in 9th week in 100 % CD containing vermibin, whereas maximum urease activity was 1208 μg NH4 (-)N g(-1) h(-1) in 3rd week in 100 % CD containing vermibin. The enzyme activity and microbial counts were lesser in ETPS containing vermibins than control (100 % CD). The growth and fecundity of the worms in different vermibins were also investigated. The results showed that initially biomass and fecundity of the worms increased but decreased at the later stages due to non-availability of the palatable feed. This showed that quality and palatability of food directly affect biological parameters of the system. PMID:25982984

  8. Wear Characterization of Carbon Nanotubes Reinforced Acetal Spur, Helical, Bevel and Worm Gears Using a TS Universal Test Rig

    Science.gov (United States)

    Yousef, Samy; Osman, T. A.; Abdalla, Abdelrahman H.; Zohdy, Gamal A.

    2015-12-01

    Although the applications of nanotechnologies are increasing, there remains a significant barrier between nanotechnology and machine element applications. This work aims to remove this barrier by blending carbon nanotubes (CNT) with common types of acetal polymer gears (spur, helical, bevel and worm). This was done by using adhesive oil (paraffin) during injection molding to synthesize a flange and short bars containing 0.02% CNT by weight. The flanges and short bars were machined using hobbing and milling machines to produce nanocomposite polymer gears. Some defects that surfaced in previous work, such as the appearance of bubbles and unmelted pellets during the injection process, were avoided to produce an excellent dispersion of CNT in the acetal. The wear resistances of the gears were measured by using a TS universal test rig using constant parameters for all of the gears that were fabricated. The tests were run at a speed of 1420 rpm and a torque of 4 Nm. The results showed that the wear resistances of the CNT/acetal gears were increased due to the addition of CNT, especially the helical, bevel and worm gears.

  9. Proteomic Changes between Male and Female Worms of the Polychaetous Annelid Neanthes arenaceodentata before and after Spawning

    KAUST Repository

    Chandramouli, Kondethimmanahalli

    2013-08-30

    The Neanthes acuminata species complex (Polychaeta) are cosmopolitan in distribution. Neanthes arenaceodentata, complex, has been widely used as toxicological test animal in the marine environment. Method of reproduction is unique in this polychaete complex. Same sexes fight and opposite sexes lie side by side until egg laying. Females lose about 75% of their weight and die after laying eggs. The male, capable of reproducing up to nine times, fertilizes the eggs and incubates the embryos for 3-4 weeks. The objective of this study was to determine if there is any set of proteins that influences this unique pattern of reproduction. Gel-based two-dimensional electrophoresis (2-DE) and gel-free quantitative proteomics methods were used to identify differential protein expression patterns before and after spawning in both male and female N. arenaceodentata. Males showed a higher degree of similarity in protein expression patterns but females showed large changes in phosphoproteme before and after spawning. There was a decrease (about 70%) in the number of detected phosphoproteins in spent females. The proteins involved in muscular development, cell signaling, structure and integrity, and translation were differentially expressed. This study provides proteomic insights of the male and female worms that may serve as a foundation for better understanding of unusual reproductive patterns in polychaete worms. © 2013 Chandramouli et al.

  10. Barcoding of arrow worms (Phylum Chaetognatha from three oceans: genetic diversity and evolution within an enigmatic phylum.

    Directory of Open Access Journals (Sweden)

    Robert M Jennings

    Full Text Available Arrow worms (Phylum Chaetognatha are abundant planktonic organisms and important predators in many food webs; yet, the classification and evolutionary relationships among chaetognath species remain poorly understood. A seemingly simple body plan is underlain by subtle variation in morphological details, obscuring the affinities of species within the phylum. Many species achieve near global distributions, spanning the same latitudinal bands in all ocean basins, while others present disjunct ranges, in some cases with the same species apparently found at both poles. To better understand how these complex evolutionary and geographic variables are reflected in the species makeup of chaetognaths, we analyze DNA barcodes of the mitochondrial cytochrome oxidase c subunit I (COI gene, from 52 specimens of 14 species of chaetognaths collected mainly from the Atlantic Ocean. Barcoding analysis was highly successful at discriminating described species of chaetognaths across the phylum, and revealed little geographical structure. This barcode analysis reveals hitherto unseen genetic variation among species of arrow worms, and provides insight into some species relationships of this enigmatic group.

  11. Barcoding of arrow worms (Phylum Chaetognatha) from three oceans: genetic diversity and evolution within an enigmatic phylum.

    Science.gov (United States)

    Jennings, Robert M; Bucklin, Ann; Pierrot-Bults, Annelies

    2010-01-01

    Arrow worms (Phylum Chaetognatha) are abundant planktonic organisms and important predators in many food webs; yet, the classification and evolutionary relationships among chaetognath species remain poorly understood. A seemingly simple body plan is underlain by subtle variation in morphological details, obscuring the affinities of species within the phylum. Many species achieve near global distributions, spanning the same latitudinal bands in all ocean basins, while others present disjunct ranges, in some cases with the same species apparently found at both poles. To better understand how these complex evolutionary and geographic variables are reflected in the species makeup of chaetognaths, we analyze DNA barcodes of the mitochondrial cytochrome oxidase c subunit I (COI) gene, from 52 specimens of 14 species of chaetognaths collected mainly from the Atlantic Ocean. Barcoding analysis was highly successful at discriminating described species of chaetognaths across the phylum, and revealed little geographical structure. This barcode analysis reveals hitherto unseen genetic variation among species of arrow worms, and provides insight into some species relationships of this enigmatic group. PMID:20376348

  12. Resistance induced by normal and irradiated Schistosoma mansoni: ability of various worm stages to serve as inducers and targets in mice

    Energy Technology Data Exchange (ETDEWEB)

    Dean, D.A.; Cioli, D.; Bukowski, M.A.

    1981-09-01

    Lung stage schistosomula exposed to 50 kilorads of gamma irradiation induced significant resistance to challenge infection with Schistosoma mansoni following intravenous (tail or mesenteric vein), intramuscular, or intraperitoneal injection into mice. Similar or higher levels were induced with irradiated cercariae, while irradiated 3- or 4-week-old worms induced little resistance. Non-irradiated day 6 and day 12 lung schistosomula injected into mice immunized with irradiated cercariae were susceptible to elimination, though to a lesser extent than a challenge infection administered at the cercarial stage. Day 20 liver worms injected into a mesenteric vein were not susceptible to irradiated cercaria-induced resistance. In contrast, cercariae, day 6 lung schistosomula, day 12 lung schistosomula and day 20 liver worms were all susceptible to the resistance induced by a chronic (non-irradiated) infection.

  13. Resistance induced by normal and irradiated Schistosoma mansoni: ability of various worm stages to serve as inducers and targets in mice

    International Nuclear Information System (INIS)

    Lung stage schistosomula exposed to 50 kilorads of gamma irradiation induced significant resistance to challenge infection with Schistosoma mansoni following intravenous (tail or mesenteric vein), intramuscular, or intraperitoneal injection into mice. Similar or higher levels were induced with irradiated cercariae, while irradiated 3- or 4-week-old worms induced little resistance. Non-irradiated day 6 and day 12 lung schistosomula injected into mice immunized with irradiated cercariae were susceptible to elimination, though to a lesser extent than a challenge infection administered at the cercarial stage. Day 20 liver worms injected into a mesenteric vein were not susceptible to irradiated cercaria-induced resistance. In contrast, cercariae, day 6 lung schistosomula, day 12 lung schistosomula and day 20 liver worms were all susceptible to the resistance induced by a chronic (non-irradiated) infection

  14. Combining Biomimetic Block Copolymer Worms with an Ice‐Inhibiting Polymer for the Solvent‐Free Cryopreservation of Red Blood Cells

    Science.gov (United States)

    Mitchell, Daniel E.; Lovett, Joseph R.; Armes, Steven P.

    2016-01-01

    Abstract The first fully synthetic polymer‐based approach for red‐blood‐cell cryopreservation without the need for any (toxic) organic solvents is reported. Highly hydroxylated block copolymer worms are shown to be a suitable replacement for hydroxyethyl starch as a extracellular matrix for red blood cells. When used alone, the worms are not a particularly effective preservative. However, when combined with poly(vinyl alcohol), a known ice‐recrystallization inhibitor, a remarkable additive cryopreservative effect is observed that matches the performance of hydroxyethyl starch. Moreover, these block copolymer worms enable post‐thaw gelation by simply warming to 20 °C. This approach offers a new solution for both the storage and transport of red blood cells and also a convenient matrix for subsequent 3D cell cultures. PMID:26822631

  15. Combining Biomimetic Block Copolymer Worms with an Ice-Inhibiting Polymer for the Solvent-Free Cryopreservation of Red Blood Cells.

    Science.gov (United States)

    Mitchell, Daniel E; Lovett, Joseph R; Armes, Steven P; Gibson, Matthew I

    2016-02-18

    The first fully synthetic polymer-based approach for red-blood-cell cryopreservation without the need for any (toxic) organic solvents is reported. Highly hydroxylated block copolymer worms are shown to be a suitable replacement for hydroxyethyl starch as a extracellular matrix for red blood cells. When used alone, the worms are not a particularly effective preservative. However, when combined with poly(vinyl alcohol), a known ice-recrystallization inhibitor, a remarkable additive cryopreservative effect is observed that matches the performance of hydroxyethyl starch. Moreover, these block copolymer worms enable post-thaw gelation by simply warming to 20 °C. This approach offers a new solution for both the storage and transport of red blood cells and also a convenient matrix for subsequent 3D cell cultures. PMID:26822631

  16. Pharmacological Analyses of Protein Kinases Regulating Egg Maturation in Marine Nemertean Worms: A Review and Comparison with Mammalian Eggs

    Directory of Open Access Journals (Sweden)

    Alicia Marquardt

    2010-08-01

    Full Text Available For development to proceed normally, animal eggs must undergo a maturation process that ultimately depends on phosphorylations of key regulatory proteins. To analyze the kinases that mediate these phosphorylations, eggs of marine nemertean worms have been treated with pharmacological modulators of intracellular signaling pathways and subsequently probed with immunoblots employing phospho-specific antibodies. This article both reviews such analyses and compares them with those conducted on mammals, while focusing on how egg maturation in nemerteans is affected by signaling pathways involving cAMP, mitogen-activated protein kinases, Src-family kinases, protein kinase C isotypes, AMP-activated kinase, and the Cdc2 kinase of maturation-promoting factor.

  17. Worm Algorithm and Diagrammatic Monte Carlo: A New Approach to Continuous-Space Path Integral Monte Carlo Simulations

    CERN Document Server

    Boninsegni, M; Svistunov, B V

    2006-01-01

    A detailed description is provided of a new Worm Algorithm, enabling the accurate computation of thermodynamic properties of quantum many-body systems in continuous space, at finite temperature. The algorithm is formulated within the general Path Integral Monte Carlo (PIMC) scheme, but also allows one to perform quantum simulations in the grand canonical ensemble, as well as to compute off-diagonal imaginary-time correlation functions, such as the Matsubara Green function, simultaneously with diagonal observables. Another important innovation consists of the expansion of the attractive part of the pairwise potential energy into elementary (diagrammatic) contributions, which are then statistically sampled. This affords a complete microscopic account of the long-range part of the potential energy, while keeping the computational complexity of all updates independent of the size of the simulated system. The computational scheme allows for efficient calculations of the superfluid fraction and off-diagonal correla...

  18. Thermodynamics of polymer nematics described with a worm-like chain model: particle-based simulations and SCF theory calculations

    Science.gov (United States)

    Greco, Cristina; Yiang, Ying; Kremer, Kurt; Chen, Jeff; Daoulas, Kostas

    Polymer liquid crystals, apart from traditional applications as high strength materials, are important for new technologies, e.g. Organic Electronics. Their studies often invoke mesoscale models, parameterized to reproduce thermodynamic properties of the real material. Such top-down strategies require advanced simulation techniques, predicting accurately the thermodynamics of mesoscale models as a function of characteristic features and parameters. Here a recently developed model describing nematic polymers as worm-like chains interacting with soft directional potentials is considered. We present a special thermodynamic integration scheme delivering free energies in particle-based Monte Carlo simulations of this model, avoiding thermodynamic singularities. Conformational and structural properties, as well as Helmholtz free energies are reported as a function of interaction strength. They are compared with state-of-art SCF calculations invoking a continuum analog of the same model, demonstrating the role of liquid-packing and fluctuations.

  19. Incidental detection of ascariasis worms on USG in a protein energy malnourished (PEM) child with abdominal pain.

    Science.gov (United States)

    Suthar, Pokhraj Prakashchandra; Doshi, Rajkumar Prakashbhai; Mehta, Chetan; Vadera, Khyati P

    2015-01-01

    A 10-year-old child presented with dull aching periumbilical abdominal pain for 15 days. The child was not gaining weight despite a good appetite. Physical examination of the child revealed grade-I protein energy malnourishment (PEM) according to IAP (Indian Academic of Paediatrics) classification. The rest of the systemic examination was normal. Routine blood investigation revealed anaemia with eosinophilia. Abdominal ultrasonography did not show any abnormality with curvilinear transducer (3.5-5 MHz), however, linear ultrasound transducer (7.5-12 MHz) with harmonic tissue imaging showed worms in the lumen of the small intestine with curling movement on real time scanning. Stool examination for the eggs of ascariasis was positive. The patient was treated with antihelminthic drugs. Dietary modification for the PEM was advised. After 3 months of treatment, the patient improved and stool examination for Ascaris was negative on follow-up. PMID:25766437

  20. A deep sequencing approach to comparatively analyze the transcriptome of lifecycle stages of the filarial worm, Brugia malayi.

    Directory of Open Access Journals (Sweden)

    Young-Jun Choi

    2011-12-01

    Full Text Available BACKGROUND: Developing intervention strategies for the control of parasitic nematodes continues to be a significant challenge. Genomic and post-genomic approaches play an increasingly important role for providing fundamental molecular information about these parasites, thus enhancing basic as well as translational research. Here we report a comprehensive genome-wide survey of the developmental transcriptome of the human filarial parasite Brugia malayi. METHODOLOGY/PRINCIPAL FINDINGS: Using deep sequencing, we profiled the transcriptome of eggs and embryos, immature (≤3 days of age and mature microfilariae (MF, third- and fourth-stage larvae (L3 and L4, and adult male and female worms. Comparative analysis across these stages provided a detailed overview of the molecular repertoires that define and differentiate distinct lifecycle stages of the parasite. Genome-wide assessment of the overall transcriptional variability indicated that the cuticle collagen family and those implicated in molting exhibit noticeably dynamic stage-dependent patterns. Of particular interest was the identification of genes displaying sex-biased or germline-enriched profiles due to their potential involvement in reproductive processes. The study also revealed discrete transcriptional changes during larval development, namely those accompanying the maturation of MF and the L3 to L4 transition that are vital in establishing successful infection in mosquito vectors and vertebrate hosts, respectively. CONCLUSIONS/SIGNIFICANCE: Characterization of the transcriptional program of the parasite's lifecycle is an important step toward understanding the developmental processes required for the infectious cycle. We find that the transcriptional program has a number of stage-specific pathways activated during worm development. In addition to advancing our understanding of transcriptome dynamics, these data will aid in the study of genome structure and organization by facilitating

  1. Dual RNA-seq of parasite and host reveals gene expression dynamics during filarial worm-mosquito interactions.

    Directory of Open Access Journals (Sweden)

    Young-Jun Choi

    2014-05-01

    Full Text Available BACKGROUND: Parasite biology, by its very nature, cannot be understood without integrating it with that of the host, nor can the host response be adequately explained without considering the activity of the parasite. However, due to experimental limitations, molecular studies of parasite-host systems have been predominantly one-sided investigations focusing on either of the partners involved. Here, we conducted a dual RNA-seq time course analysis of filarial worm parasite and host mosquito to better understand the parasite processes underlying development in and interaction with the host tissue, from the establishment of infection to the development of infective-stage larva. METHODOLOGY/PRINCIPAL FINDINGS: Using the Brugia malayi-Aedes aegypti system, we report parasite gene transcription dynamics, which exhibited a highly ordered developmental program consisting of a series of cyclical and state-transitioning temporal patterns. In addition, we contextualized these parasite data in relation to the concurrent dynamics of the host transcriptome. Comparative analyses using uninfected tissues and different host strains revealed the influence of parasite development on host gene transcription as well as the influence of the host environment on parasite gene transcription. We also critically evaluated the life-cycle transcriptome of B. malayi by comparing developmental stages in the mosquito relative to those in the mammalian host, providing insight into gene expression changes underpinning the mosquito-borne parasitic lifestyle of this heteroxenous parasite. CONCLUSIONS/SIGNIFICANCE: The data presented herein provide the research community with information to design wet lab experiments and select candidates for future study to more fully dissect the whole set of molecular interactions of both organisms in this mosquito-filarial worm symbiotic relationship. Furthermore, characterization of the transcriptional program over the complete life cycle of

  2. Frequencies of chromosomal aberrations and sister chromatid exchanges in the benthic worm Neanthes arenaceodentata exposed to ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, F.L.; Rice, D.W. Jr., Moore, D.H.

    1984-07-01

    Traditional bioassays are unsuitable for assessing sublethal effects from ocean disposal of low-level radioactive waste because mortality and phenotypic responses are not anticipated. We compared the usefulness of chromosomal aberration and sister chromatid exchange (SCE) induction as measures of low-level radiation effects in a sediment-dwelling marine worm, Neanthes arenaceodentata. The SCEs, in contrast to chromosomal aberrations, do not alter the overall chromosome morphology and in mammalian cells appear to be a more sensitive indicator of DNA alterations caused by environmental mutagens. Newly hatched larvae were exposed to two radiation-exposure regimes of either x rays at a high dose rate of 0.7 Gy (70 rad)/min for as long as 5.5 min or to /sup 60/Co gamma rays at a low dose rate of from 4.8 x 10/sup -5/ to 1.2 x 10/sup -1/ Gy (0.0048 to 12 rad)/h for 24 h. After irradiation, the larvae were exposed to 3 x 10/sup -5/M bromodeoxyuridine (BrdUrd) for 28 h (x-ray-irradiated larvae) or for 54 h (/sup 60/Co-irradiated larvae). Larval cells were examined for the proportion of cells in first, second, and third or greater division. Frequencies of chromosomal aberrations and SCEs were determined in first and second division cells, respectively. Results from x-ray irradiation indicated that dose-related increases occur in chromosome and chromatid deletions, but a dose of equal or greater 2 Gy (equal to or greater than 200 rad) was required to observe a significant increase. Worm larvae receiving /sup 60/Co irradiation showed elevated SCE frequencies with a significant increase of 0.6 Gy (60 rad). We suggest that both SCEs and chromosomal aberrations may be useful for measuring effects on genetic material induced by radiation. 56 references, 7 figures, 9 tables.

  3. Frequencies of chromosomal aberrations and sister chromatid exchanges in the benthic worm Neanthes arenaceodentata exposed to ionizing radiation

    International Nuclear Information System (INIS)

    Traditional bioassays are unsuitable for assessing sublethal effects from ocean disposal of low-level radioactive waste because mortality and phenotypic responses are not anticipated. We compared the usefulness of chromosomal aberration and sister chromatid exchange (SCE) induction as measures of low-level radiation effects in a sediment-dwelling marine worm, Neanthes arenaceodentata. The SCEs, in contrast to chromosomal aberrations, do not alter the overall chromosome morphology and in mammalian cells appear to be a more sensitive indicator of DNA alterations caused by environmental mutagens. Newly hatched larvae were exposed to two radiation-exposure regimes of either x rays at a high dose rate of 0.7 Gy (70 rad)/min for as long as 5.5 min or to 60Co gamma rays at a low dose rate of from 4.8 x 10-5 to 1.2 x 10-1 Gy (0.0048 to 12 rad)/h for 24 h. After irradiation, the larvae were exposed to 3 x 10-5M bromodeoxyuridine (BrdUrd) for 28 h (x-ray-irradiated larvae) or for 54 h (60Co-irradiated larvae). Larval cells were examined for the proportion of cells in first, second, and third or greater division. Frequencies of chromosomal aberrations and SCEs were determined in first and second division cells, respectively. Results from x-ray irradiation indicated that dose-related increases occur in chromosome and chromatid deletions, but a dose of equal or greater 2 Gy (equal to or greater than 200 rad) was required to observe a significant increase. Worm larvae receiving 60Co irradiation showed elevated SCE frequencies with a significant increase of 0.6 Gy (60 rad). We suggest that both SCEs and chromosomal aberrations may be useful for measuring effects on genetic material induced by radiation. 56 references, 7 figures, 9 tables

  4. Antigens of worms and eggs showed a differentiated detection of specific IgG according to the time of Schistosoma mansoni infection in mice

    Directory of Open Access Journals (Sweden)

    Rafaella Fortini Queiroz Grenfell

    2012-08-01

    Full Text Available INTRODUCTION: The correlation between the immunological assay and the antibody titer can offer a tool for the experimental analysis of different phases of the disease. METHODS: Two simple immunological assays for Schistosoma mansoni in mice sera samples based on specific IgG detection for worms soluble antigens and eggs soluble antigens were standardized and evaluated in our laboratory. Fifty mice were used in negative and positive groups and the results obtained by enzyme-linked immunosorbent assays (ELISA assays were compared with the number of worms counted and the IgG titers at different times of infection. RESULTS: Data showed that ELISA using adult worm antigens (ELISA-SWAP presented a satisfactory correlation between the absorbance value of IgG titers and the individual number of worms counted after perfusion technique (R²=0.62. In addition, ELISA-SWAP differentially detected positive samples with 30 and 60 days post infection (p=0.011 and 0.003, respectively, whereas ELISA using egg antigens (ELISA-SEA detected samples after 140 days (p=0.03. CONCLUSIONS: These data show that the use of different antigens in immunological methods can be used as potential tools for the analysis of the chronological evolution of S. mansoni infection in murine schistosomiasis. Correlations with human schistosomiasis are discussed.

  5. A method of obtaining dietary data for slow worms (Anguis fragilis) by means of non-harmful cooling and results from a Danish population

    DEFF Research Database (Denmark)

    Pedersen, Iben; Jensen, Jan Kjærgaard; Toft, Søren

    2009-01-01

    adults. The regurgitations revealed that the slow worms preyed on small snails, slugs, pill millipedes (Glomeris marginata), earthworms and Lepidoptera larvae. There were seasonal changes in taxon composition of the diet but no ontogenetic or sex-related differences. The food quality of selected prey...

  6. B+ Address Tree Diffusion Strategy for Benign Worm%良性蠕虫的B+地址树扩散策略

    Institute of Scientific and Technical Information of China (English)

    陈伟; 孙志勇; 许德武

    2012-01-01

    为提高良性蠕虫对抗恶意蠕虫时的效率,提出一种良性蠕虫的B+地址树扩散策略.在传递的信息中带有控制信息,主动扩散并行信息,以便使良性蠕虫处于可控的扩散状态.根据B+地址树设计动态生成算法,利用Scilab进行扩散模拟测试.测试结果表明,与已有策略相比,该策略的良性蠕虫扩散速度更快,对网络的影响更小.%In order to improve the efficiency of the benign worm when fight against the malicious worm, this paper proposes a B+ address tree diffusion strategy for benign worm. It actively spreads the parallel information. In passing information, there is control information, so as to make the benign worms in a controllable diffusion state. According to B+ address tree, it designs the dynamic generation algorithm, and uses Scilab to do the diffusion simulation test. Testing results show that this strategy has faster propagation speed and less network impact on network compared with the traditional ones.

  7. Annual Survey of Horsehair Worm Cysts in Northern Taiwan, with Notes on a Single Seasonal Infection Peak in Chironomid Larvae (Diptera: Chironomidae).

    Science.gov (United States)

    Chiu, Ming-Chung; Huang, Chin-Gi; Wu, Wen-Jer; Shiao, Shiuh-Feng

    2016-06-01

    The life cycle of the freshwater horsehair worm typically includes a free-living phase (adult, egg, larva) and a multiple-host parasitic phase (aquatic paratenic host, terrestrial definitive host). Such a life cycle involving water and land can improve energy flow in riparian ecosystems; however, its temporal dynamics in nature have rarely been investigated. This study examined seasonal infection with cysts in larval Chironominae (Diptera: Chironomidae) in northern Taiwan. In the larval chironomids, cysts of 3 horsehair worm species were identified. The cysts of the dominant species were morphologically similar to those of Chordodes formosanus. Infection with these cysts increased suddenly and peaked 2 mo after the reproductive season of the adult horsehair worms. Although adult C. formosanus emerged several times in a year, only 1 distinct infection peak was detected in September in the chironomid larvae. Compared with the subfamily Chironominae, samples from the subfamilies Tanypodinae and Orthocladiinae were less parasitized. This indicates that the feeding behavior of the chironomid host likely affects horsehair worm cyst infections; however, bioconcentration in predatory chironomids was not detected. PMID:26885875

  8. Influence of temperature and substrate on infection rate, triactinomyxon production, and release duration from eastern tubifex worms infected with Myxobolus cerebralis

    Science.gov (United States)

    Waldrop, Thomas; Blazer, Vicki; Smith, David; Schill, Bane; Densmore, Christine

    1999-01-01

    Salmonid whirling disease is caused by Myxobolus cerebralis, a metazoan parasite with a two host life cycle involving salmonid fish a an aquatic oligochaete, Tubifex tubifex (Wolf, Markiw and Hiltunen, 1986). Whirling disease has been reported in 22 U.S. states with the greatest losses occurring in the salmonid fisheries of western and Midwestern states. Although whirling disease is endemic in the eastern United States, serious documented losses to wild populations have not been reported. Two high priority research needs identified in 1996 were a better understanding of how worm and parasite populations might differ from different geographic areas and how environmental factors affect the various stages of whirling disease. To begin to address these research needs we established "eastern" populations of worms, parasite and fish hosts. This abstract will present data on the effects of temperature and substrate upon eastern T. tubifex worms infected with an eastern isolate of M. cerebralis. The influences of these abiotic factors upon the ability to infect the worms and subsequently their ability to produce waterborne triactinomyxons.

  9. Opportunities for Sex Education and Personal and Social Education (PSE) through Science Lessons: The Comments of Primary Pupils When Observing Meal Worms and Brine Shrimp.

    Science.gov (United States)

    Tunnicliffe, Sue Dale; Reiss, Michael J.

    1999-01-01

    Presents a characterization of students' comments during observation of meal worms or brine shrimp. Finds that many student comments had to do with sex, reproduction, death, violence, and the life history of the organisms. Significant differences in conversations occurred across age and gender groups. Contains 32 references. (Author/WRM)

  10. Sediment-worm interactions: transfer of 65Zn, 109Cd and sup(110m)Ag from marine sediment by Nereis diversicolor

    International Nuclear Information System (INIS)

    Radiotracer experiments to understand the role of benthic worms in transferring 65Zn, 109Cd and sup(110m)Ag from marine sediments to marine food webs are described. Sediments were made radioactive by adding 30 to 50μCi of the appropriate high specific activity isotope to 500 ml of sea water and mixing with 100 cm3 of sediment. The 65Zn and 109Cd were added as chlorides and the sup(110m)Ag was added as nitrate. Relative accumulation from radioactive sediments and the loss rates of the metals from N. diversicolor were determined at different time intervals. Radioactive worms were transferred to fresh sediments and were periodically radioanalysed. It was observed that simple ingestion of subsurface radioactive sediments is a less effective route of Zn transfer to the worm than by deposit feeding at the sediment-water interface. Cadmium appears to be much less tightly bound to marine sediment than zinc. Worms which accumulated sup(110m)Ag from sediment during a 20 day exposure lost it at a faster rate than 65Zn accumulated during a 5 day exposure

  11. In vitro and in vivo anthelmintic activity of (-)-6,6'-dinitrohinokinin against schistosomula and juvenile and adult worms of Schistosoma mansoni.

    Science.gov (United States)

    Pereira, Ana C; Silva, Márcio L A E; Souza, Julia Medeiros; Laurentiz, Rosangela S de; Rodrigues, Vanderlei; Januário, Ana H; Pauletti, Patrícia M; Tavares, Denise C; Filho, Ademar A Da Silva; Cunha, Wilson R; Bastos, Jairo K; Magalhães, Lizandra G

    2015-09-01

    The chemotherapy of schistosomiasis relies on the use of praziquantel. However, concerns over drug resistance have encouraged the search for new drug leads. This paper is the first report on the in vitro and in vivo activity of (-)-6,6'-dinitrohinokinin (DNK) against Schistosoma mansoni. In vitro, the lethal concentrations for 50% of parasites (LC50) of DNK against adult worms were 103.9±3.6 and 102.5±4.8μM at 24 and 72h, respectively. Scanning electron microscopy images showed extensive tegumental alterations such as peeling and smaller numbers of tubercles in the spine of adult worms. DNK also elicited high mortality of schistosomula, with LC50 values of 57.4±2.3, 32.5±0.9, and 20.4±1.2μM at 24, 48, and 72h, respectively. DNK displayed moderate activity against the juvenile liver parasite, with an LC50 value of 179.5±2.3 μM at 72h. This compound reduced the total number of eggs by over 83%, and it affected the development of eggs produced by adult worms. The selectivity index showed that at 24h, DNK was 8.5 and 15.4 times more toxic to the adult worms and schistosomula than to Chinese hamster lung fibroblast cells, respectively. Treatment of infected mice with DNK moderately decreased worm burden (33.8-52.3%), egg production (40.7-60.0%), and spleen and liver weights. Together, our results indicated that DNK presents moderate in vitro and in vivo activities against S. mansoni, and it might therefore be interesting to explore the structure-activity relationship of the antischistosomal activity of this compound. PMID:26071648

  12. Partial characterization of superoxide dismutase activity in the Barber pole worm-Haemonchus contortus infecting Capra hircus and abomasal tissue extracts

    Institute of Scientific and Technical Information of China (English)

    Sadia Rashid; Malik Irshadullah

    2014-01-01

    Objective: To determine the activity of superoxide dismutase (SOD) in the male and female haematophagous caprine worms, Haemonchus contortus infecting Capra hircus, and their E/S products and also to analyse the effect of Haemonchus infection on the level of host SOD. Methods: The SOD activity was analysed by using the pyrogallol autoxidation assay and non-denaturing polyacrylamide gel electrophoresis followed by specific enzyme staining by riboflavin-nitroblue tetrazolium method. Results: The adult females were found to have higher enzyme activity than the male worms. Appreciable amount of SOD activity was also detected in the worm culture medium and female worms secreted more SOD in comparison to the male parasites. The SOD activity was negatively correlated to the worm burden. Statistically significant decrease in SOD activity (P Conclusions:Haemonchus contortus is a key model parasite for drug and vaccine discovery. The presences of SOD activity in appreciable amount in the parasite as well as its E/S products indicate that it has a well-developed active antioxidant system to protect itself from the host immune attack. SOD could be the target for vaccine development which is the need of the hour as mass drug administration for parasite control has resulted in anthelmintic resistance across the globe and threatens the viability of sheep and goat industry in many regions of the world. The infection with Haemonchus causes a drastic reduction in SOD activity of the host tissue thus effecting its protective potential. One characteristic SOD band was found in the females which was not present in any other preparations and thus could be exploited for further studies on diagnostic/control measures.

  13. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - MILWAUKEE WORM DRIVE CIRCULAR SAW OENHP NUMBER: 2001-02, VERSION A

    International Nuclear Information System (INIS)

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Milwaukee worm drive circular saw was assessed on August 14, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Milwaukee worm drive circular saw is a hand-held tool with a 7 1/4-inch diameter circular blade for cutting wood. The saw contains a fixed upper and a retractable lower blade guard to prevent access to the blade during use. The unit is operated with an on/off guarded trigger switch; and is supported with a handgrip mounted on top of the saw. An adjustable lever sets the depth of cut. The retractable blade guard permits blind or plunge cuts and protects from blade access during shutdown and blade coast. Kickback, the sudden reaction to a pinched blade, is possible when using this saw and could cause the saw to lift up and out of the work piece toward the operator. Proper work position and firm control of the saw minimizes the potential for a sprain or strain. Care needs to be exercised to support the work piece properly and to not force the tool. Personal noise sampling indicated that one worker was near the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) while the other was at the Action Level with time-weighted averages (TWA's) of 82.7 and 84.6 dBA, respectively. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it

  14. Synthesis and characterization of a new family of alkylammonium–chromium phosphates with worm-like morphology

    International Nuclear Information System (INIS)

    A series of layered alkylammonium–chromium phosphates, formulated as [CnH2n+1NH3]Cr(OH)PO4 (n=2–6), has been synthesized under hydrothermal conditions. The interlayer spacing, increasing linearly with the increase of alkyl-chain length from 13.61 Å (n=2) to 21.20 Å (n=6), is occupied by a double sheet of packed amine molecules with a tilt angle of ca. 51° respect to the inorganic sheet. The powders are constituted by circular plates (diameter=0.5–3 µm, thickness=∼50 nm) with central holes when n=4–6, stacked in axial direction showing worm-like morphologies. The presence of holes, and some corrugated and zig-zag fashions observed on the edge of thin circular plates are the most probable ways for the reduction of the steric tensions between organic and inorganic portions in these hybrid materials. The thermal and thermo-oxidative stability of selected compounds have been studied, including the determination of activation energy data for the decomposition processes. - Graphical abstract: A novel series of layered alkylammonium–chromium phosphates, [CnH2n+1NH3]Cr(OH)PO4 (n=2–6), was obtained and characterized. The interlayer spacing, increasing linearly with the increase of alkyl-chain length, is occupied by a double sheet of packed amine molecules. The powders are constituted by circular plates (diameter=0.5–3 µm, thickness=∼50 nm) with central holes when n=4–6, stacked in axial direction showing worm-like morphologies. - Highlights: • A series of alkylammonium–chromium phosphates has been obtained by the hydrothermal method. • The interlayer spacing increases linearly with the increase of alkyl-chain length. • The interlayer spacing is occupied by a double sheet of packed amine molecules. • The powders are constituted by stacked circular plates showing wormlike morphology. • Thermal behaviour depends on the atmosphere used and the intercalated amine

  15. Association study in naturally infected helminth layers shows evidence for influence of interferon-gamma gene variants on Ascaridia galli worm burden.

    Science.gov (United States)

    Lühken, Gesine; Gauly, Matthias; Kaufmann, Falko; Erhardt, Georg

    2011-01-01

    Single nucleotide polymorphisms (SNPs) in the genes for interleukin-4, -13 and interferon-gamma, and 21 additional SNPs which previously had been significantly associated with immune traits in the chicken, were genotyped in white and brown layer hens and analyzed for their association with helminth burden following natural infections. A nucleotide substitution located upstream of the promoter of the interferon-gamma gene was significantly associated with the log transformed number of Ascaridia galli in the brown layer line (genotype CC: 6.4 ± 1.0 worms; genotype CT: 11.7 ± 2.2 worms). Therefore, IFNG seems to be a promising candidate gene for further studies on helminth resistance in the chicken. PMID:21749701

  16. Association study in naturally infected helminth layers shows evidence for influence of interferon-gamma gene variants on Ascaridia galli worm burden

    Directory of Open Access Journals (Sweden)

    Lühken Gesine

    2011-07-01

    Full Text Available Abstract Single nucleotide polymorphisms (SNPs in the genes for interleukin-4, -13 and interferon-gamma, and 21 additional SNPs which previously had been significantly associated with immune traits in the chicken, were genotyped in white and brown layer hens and analyzed for their association with helminth burden following natural infections. A nucleotide substitution located upstream of the promoter of the interferon-gamma gene was significantly associated with the log transformed number of Ascaridia galli in the brown layer line (genotype CC: 6.4 ± 1.0 worms; genotype CT: 11.7 ± 2.2 worms. Therefore, IFNG seems to be a promising candidate gene for further studies on helminth resistance in the chicken.

  17. Phylogeny and genetic diversity of palolo worms (Palola, Eunicidae) from the tropical North Pacific and the Caribbean.

    Science.gov (United States)

    Schulze, Anja

    2006-02-01

    Palolo worms (Palola, Eunicidae) are best known for their annual mass spawnings, or "risings," in the South Pacific. Palola currently contains 14 morphologically similar species, mostly from shallow tropical waters. In this study, 60 specimens of Palola from nine locations in the tropical North Pacific and the Caribbean were sequenced for the two mitochondrial markers cytochrome c oxidase subunit I and 16S ribosomal RNA to infer phylogenetic relationships, genetic diversity, and phylogeography within the taxon. Phylogenetic analysis was performed using Bayesian statistics and parsimony. Vouchers of the same specimens were examined morphologically. Two major clades (A and B) can be distinguished within the monophyletic Palola. A number of individuals in clade B bear rows of ventral eyespots in the posterior body region, typical for swarming P. viridis and probably a synapomorphy for clade B. No morphological synapomorphy was found for clade A. Haplotypes from divergent clades often co-occur in the same location. Some haplotypes are geographically widespread, in one case covering the entire east-west expansion of the tropical Pacific. These results imply that despite the apparent absence of teleplanic larvae in eunicid polychaetes, long-distance dispersal is possible in at least some lineages of Palola. With the first taste of palolo I understood the Samoans' love for it. Certainly it suggested a salty caviar, but with something added, a strong, rich whiff of the mystery and fecundity of the ocean depths. -R. Steinberg. Pacific and Southeast Asian cooking. Time-Life Books, New York, 1970. PMID:16501062

  18. Radiation-induced change in mating and reproductive potential of the cotton leaf worm, Spodoptera Littoralis (Boisd.)

    International Nuclear Information System (INIS)

    Among untreated cotton leaf worm, Spodoptera Littoralis (Boisd.), 5.6% was unmated, 72.5 % mated once or twice and 21.9% mated three or four times. The female fecundity and egg fertility were not significantly affected by the number of matings. Full-grown male pupae were treated with 0-500 Gray of gamma radiation, the resulting adult male paired individually with untreated virgin females. The biological effects were assayed by determining the percentage of mating, number of matings, sperm transfer, female fecundity and egg hatch ability (fertility). Irradiated and unirradiated males were paired with virgin females on days 1-4 after male eclosion to determine the effects of male ageing on mating ability and the effects of delayed mating on female fecundity and egg fertility. Mating ability of the males remained high for the first and second day then gradually decreased. Fecundity of untreated females mated with treated males declined gradually with increasing radiation doses. Fertility of treated males declined almost linearly to reach 0% near 400 Gy

  19. Characterization of human gene encoding SLA/LP autoantigen and its conserved homologs in mouse,fish,fly,and worm

    Institute of Scientific and Technical Information of China (English)

    Chun-Xia Wang; Andreas Teufel; Uta Cheruti; Joachim Gr(o)tzinger; Peter R Galle; Ansgar W Lohse; Johannes Herkel

    2006-01-01

    AIM: To approach the elusive function of the SLA/LP molecule, we have characterized genomic organization and conservation of the major antigenic and functional properties of the SLA/LP molecule in various species.METHODS: By means of computational biology, we have characterized the complete SLA/LP gene, mRNA and deduced protein sequences in man, mouse,zebrafish, fly, and worm.RESULTS: The human SLA/LP gene sequence of approximately 39 kb, which maps to chromosome 4p15.2, is organized in 11 exons, of which 10 or 11 are translated, depending on the splice variant. Homologous molecules were identified in several biological model organisms. The various homologous protein sequences showed a high degree of similarity or homology, notably at those residues that are of functional importance. The only domain of the human protein sequence that lacks significant homology with homologous sequences is the major antigenic epitope recognized by autoantibodies from autoimmune hepatitis (AIH) patients.CONCLUSION: The SLA/LP molecule and its functionally relevant residues have been highly conserved throughout the evoluti n, suggesting an indispensable function of the molecule. The finding that the only non-conserved domain is the dominant antigenic epitope of the human SLA/LP sequence, suggests that SLA/LP autoimmunity is autoantigen-driven rather than being driven by molecular mimicry.

  20. Metaproteomics of a gutless marine worm and its symbiotic microbial community reveal unusual pathways for carbon and energy use

    Energy Technology Data Exchange (ETDEWEB)

    Kleiner, Manuel [Max Planck Institute for Marine Microbiology; Wentrop, C. [Max Planck Institute for Marine Microbiology; Lott, C. [Max Planck Institute for Marine Microbiology; Teeling, Hanno [Max Planck Institute for Marine Microbiology; Wetzel, Silke [Max Planck Institute for Marine Microbiology; Young, Jacque C [ORNL; Chang, Y. [Oak Ridge National Laboratory (ORNL); Shah, Manesh B [ORNL; Verberkmoes, Nathan C [ORNL; Zarzycki, Jan [University of Freiburg, Germany; Fuchs, Georg [University of Freiburg, Germany; Markert, Stephanie [Institute of Marine Biotechnology, Germany; Hempel, Kristina [Institute for Microbiology, Germany

    2012-01-01

    Low nutrient and energy availability has led to the evolution of numerous strategies for overcoming these limitations, of which symbiotic associations represent a key mechanism. Particularly striking are the associations between chemosynthetic bacteria and marine animals that thrive in nutrient-poor environments such as the deep-sea because the symbionts allow their hosts to grow on inorganic energy and carbon sources such as sulfide and CO2. Remarkably little is known about the physiological strategies that enable chemosynthetic symbioses to colonize oligotrophic environments. In this study, we used metaproteomics and metabolomics to investigate the intricate network of metabolic interactions in the chemosynthetic association between Olavius algarvensis, a gutless marine worm, and its bacterial symbionts. We propose novel pathways for coping with energy and nutrient limitation, some of which may be widespread in both free-living and symbiotic bacteria. These include (i) a pathway for symbiont assimilation of the host waste products acetate, propionate, succinate and malate, (ii) the potential use of carbon monoxide as an energy source, a substrate previously not known to play a role in marine invertebrate symbioses, (iii) the potential use of hydrogen as an energy source, (iv) the strong expression of high affinity uptake transporters, and (v) novel energy efficient steps in CO2 fixation and sulfate reduction. The high expression of proteins involved in pathways for energy and carbon uptake and conservation in the O. algarvensis symbiosis indicates that the oligotrophic nature of its environment exerted a strong selective pressure in shaping these associations.

  1. Co-evolution of marine worms and their chemoautotrophic bacterial symbionts: unexpected host switches explained by ecological fitting?

    Science.gov (United States)

    Brune, A

    2016-07-01

    Mutualistic associations of bacteria and invertebrates are widespread and encompass an enormous diversity on the side of both partners. The advantages gained from the symbiosis favour reciprocal adaptations that increase the stability of the association and can lead to codiversification of symbiont and host. While numerous examples of a strictly vertical transfer of the symbionts from parent to offspring among intracellular associations abound, little is known about the fidelity of the partners in extracellular associations, where symbionts colonize the surface or body cavity of their host. In this issue of Molecular Ecology, Zimmermann et al. () investigated the evolutionary history of the symbiotic association between a monophyletic clade of sulphur-oxidizing Gammaproteobacteria and two distantly related lineages of marine worms (nematodes and annelids). The study supports the surprising conclusion that partner fidelity does not necessarily increase with the intimacy of the association. Ectosymbionts on the cuticle of the nematodes seem to be cospeciating with their hosts, whereas endosymbionts housed in the body cavity of the annelids must have originated multiple times, probably by host switching, from ectosymbionts of sympatric nematodes. This excellent case study on the evolutionary history of invertebrate-microbe interactions supports the emerging concept that the co-evolutionary processes shaping such mutualistic symbioses include both codiversification and ecological fitting. PMID:27373707

  2. Three-dimensional reconstruction by cryoelectron microscopy of the giant hemoglobin of the polychaete worm Alvinella pompejana.

    Science.gov (United States)

    de Haas, F; Zal, F; You, V; Lallier, F; Toulmond, A; Lamy, J N

    1996-11-22

    A frozen-hydrated specimen of the hexagonal bilayer hemoglobin (HBL Hb) from the deep-sea hydrothermal vent polychaete worm Alvinella pompejana, the most thermophilic metazoan known to date, was observed in the electron microscope and subjected to three-dimensional (3D) reconstruction by the method of random conical tilt series. At a resolution of 34.6 A by the differential phase residual method and 27.7 A by the Fourier shell correlation method, the 3D volume possesses a D6 point-group symmetry. While in previous 3D reconstructions of annelid and vestimentiferan Hbs the vertices of the upper layer were 16 degrees rotated compared with those of the lower layer, in Alvinella Hb the vertices of the two hexagonal layers are almost perfectly eclipsed when viewed along the 6-fold axis. As in the HBL Hbs of Riftia pachyptila and Macrobdella decora, a central linker complex is decorated by 12 hollow globular substructures (HGS). The linker complex comprises (1) a central hexagonal toroid, (2) two internal bracelets onto which the HGSs are built, and (3) six connections between the two hexagonal layers. Each HGS is composed of six masses, which are separated when the volume is displayed at high threshold, plus one additional mass involved in the bracelet connecting the six HGSs in both hexagonal layers. The HGSs have a local pseudo 3-fold symmetry and a disposition of the high-density masses different from those of Riftia V1 Hb. PMID:8950271

  3. Three-dimensional reconstruction of the hexagonal bilayer hemoglobin of the hydrothermal vent tube worm Riftia pachyptila by cryoelectron microscopy.

    Science.gov (United States)

    de Haas, F; Zal, F; Lallier, F H; Toulmond, A; Lamy, J N

    1996-11-01

    A frozen-hydrated specimen of the V1 hemoglobin of the hydrothermal vent tube worm Riftia pachyptila was observed in the electron microscope and subjected to three-dimensional reconstruction by the method of random conical tilt series. The 3D volume possesses a D6 point-group symmetry. When viewed along its 6-fold axis the vertices of its upper hexagonal layer are 16 degrees clockwise rotated compared to those of the lower layer. A central linker complex is decorated by 12 hollow globular substructures. The linker complex comprises (i) a central hexagonal toroid, (ii) two internal bracelets onto which the hollow globular substructures are built, and (iii) six structures connecting the two hexagonal layers. The hollow globular substructures, related to the dodecamers of globin chains resulting from the dissociation of the hexagonal bilayer hemoglobin, have a local pseudo 3-fold symmetry and are composed each of three elongated structures visible when the volume is displayed at high threshold. At a resolution of 36 A, the 3D volumes of the hexagonal bilayer hemoglobins of Riftia pachyptyla and of the leech Macrobdella decora look almost perfectly identical. PMID:8953646

  4. Comparison of cellular and whole-animal bioassays for estimation of radiation effects in the polychaete worm Neanthes arenaceodentata (Polychaeta)

    International Nuclear Information System (INIS)

    The polychaete worm Neanthes arenaceodentata was used in experiments to determine possible relationships between short-term genotoxicity tests and reproductive and lethal consequences of exposure to ionizing radiation. Groups of juvenile N. arenaceodentata received one of four different radiation doses (2, 4, 8, and 16 Gy) to determine dose-effect estimates for chromosomal aberration induction, and groups of both adult and juveniles received one of seven different radiation doses (1, 4, 8.4, 46, 102, 500, and 1000 Gy) to determine dose-effect estimates for reproduction, mortality, and life span. Effects on reproduction and genetic material were observed at the lowest doses and in the same range; detrimental reproductive effects were observed at 1 to 4 Gy, and the frequency of chromosomal aberrations was significantly increased at 2 Gy. Only high doses resulted in acute mortality (greater than 500 Gy) and decreased life span (greater than 100 Gy). Dose-effect estimates for chromosomal aberration induction were dependent on radiation dose and on the stage of the cell cycle at the time of irradiation. Dose-effect estimates for reproduction were dependent on dose and the potential for repopulation of gonadal tissue. It is concluded that short-term genotoxicity test can be predictive of detrimental reproductive effects in those model systems for which basic cell kinetics and reproductive parameters are well known

  5. Micro-proteomics with iterative data analysis: Proteome analysis in C. elegans at the single worm level.

    Science.gov (United States)

    Bensaddek, Dalila; Narayan, Vikram; Nicolas, Armel; Murillo, Alejandro Brenes; Gartner, Anton; Kenyon, Cynthia J; Lamond, Angus I

    2016-02-01

    Proteomics studies typically analyze proteins at a population level, using extracts prepared from tens of thousands to millions of cells. The resulting measurements correspond to average values across the cell population and can mask considerable variation in protein expression and function between individual cells or organisms. Here, we report the development of micro-proteomics for the analysis of Caenorhabditis elegans, a eukaryote composed of 959 somatic cells and ∼1500 germ cells, measuring the worm proteome at a single organism level to a depth of ∼3000 proteins. This includes detection of proteins across a wide dynamic range of expression levels (>6 orders of magnitude), including many chromatin-associated factors involved in chromosome structure and gene regulation. We apply the micro-proteomics workflow to measure the global proteome response to heat-shock in individual nematodes. This shows variation between individual animals in the magnitude of proteome response following heat-shock, including variable induction of heat-shock proteins. The micro-proteomics pipeline thus facilitates the investigation of stochastic variation in protein expression between individuals within an isogenic population of C. elegans. All data described in this study are available online via the Encyclopedia of Proteome Dynamics (http://www.peptracker.com/epd), an open access, searchable database resource. PMID:26552604

  6. Worm algorithm and diagrammatic Monte Carlo: A new approach to continuous-space path integral Monte Carlo simulations

    Science.gov (United States)

    Boninsegni, M.; Prokof'Ev, N. V.; Svistunov, B. V.

    2006-09-01

    A detailed description is provided of a new worm algorithm, enabling the accurate computation of thermodynamic properties of quantum many-body systems in continuous space, at finite temperature. The algorithm is formulated within the general path integral Monte Carlo (PIMC) scheme, but also allows one to perform quantum simulations in the grand canonical ensemble, as well as to compute off-diagonal imaginary-time correlation functions, such as the Matsubara Green function, simultaneously with diagonal observables. Another important innovation consists of the expansion of the attractive part of the pairwise potential energy into elementary (diagrammatic) contributions, which are then statistically sampled. This affords a complete microscopic account of the long-range part of the potential energy, while keeping the computational complexity of all updates independent of the size of the simulated system. The computational scheme allows for efficient calculations of the superfluid fraction and off-diagonal correlations in space-time, for system sizes which are orders of magnitude larger than those accessible to conventional PIMC. We present illustrative results for the superfluid transition in bulk liquid He4 in two and three dimensions, as well as the calculation of the chemical potential of hcp He4 .

  7. Unexpected diversity and a new species of Epizoanthus (Anthozoa, Hexacorallia) attached to eunicid worm tubes from the Pacific Ocean.

    Science.gov (United States)

    Kise, Hiroki; Reimer, James Davis

    2016-01-01

    Epizoanthus species are generally found in association with other marine invertebrates such as hermit crabs and gastropods. Although Epizoanthus spp. are relatively common, there is limited information about their diversity and ecology due to their habitats or hosts, often being below the depths of SCUBA diving (>~50 m). In particular, the Epizoanthus fauna of the Indo-Pacific Ocean remains poorly understood. In this study, the diversity of Epizoanthus species associated with eunicid worm tubes from shallow waters in the Pacific Ocean we investigated using molecular analyses (mitochondrial cytochrome oxidase subunit 1 = COI, mitochondrial 16S ribosomal DNA = mt 16S-rDNA, nuclear internal transcribed spacer region of ribosomal DNA = ITS-rDNA) combined with morphological and ecological data. The combined data set leads us to describe two new species; Epizoanthus inazuma sp. n. and Epizoanthus beriber sp. n. Both new species are found in low-light environments: Epizoanthus inazuma sp. n. on mesophotic coral reef slopes and reef floors, or on the sides of overhangs; Epizoanthus beriber sp. n. has only been found in caves. Morphological characteristics of these two new species are very similar to Epizoanthus illoricatus Tischbierek, 1930 but the two new species are genetically distinct. Mesentery numbers and coloration of polyps may be useful diagnostic characteristics among eunicid-associated Epizoanthus species. These results demonstrate that there is high potential for other potentially undescribed zoantharian species, particularly in underwater cave habitats. PMID:27006621

  8. Age-related differences of Ascaridia galli egg output and worm burden in chickens following a single dose infection.

    Science.gov (United States)

    Gauly, M; Homann, T; Erhardt, G

    2005-03-10

    Ninety white chickens (Lohmann LSL) were reared under helminth-free conditions and divided into five groups. Four groups were artificially infected with 250 embryonated Ascaridia galli eggs at the age of 6, 12, 18 or 24 weeks. Ten birds were kept as uninfected controls. Six and 10 weeks after infection (p.i.), individual faecal egg counts (FEC) were performed. The birds were slaughtered after the second sampling and their gastrointestinal tracts were examined for the presence of adult A. galli. The FEC increased from the first to the second sampling significantly in all the infected groups. The highest increase was shown in the group infected at 12 weeks of age, whereas the increase in the other groups was relatively moderate. However, the total worm burden and mean FEC at the second sampling were highest (p0.05) between any of the groups. Thyroxine (T4) was significantly different between the groups infected at 6 and 18 weeks of age (pgalli infections in layers, whereas a bird's hormonal and immune status, related to laying activity, seems to have a significant negative impact on resistance. PMID:15725544

  9. Improved measurement scheme of the self energy in the worm-sampled hybridization-expansion quantum Monte Carlo

    Science.gov (United States)

    Han, Mancheon; Lee, Choong-Ki; Choi, Hyoung Joon

    Hybridization-expansion continuous-time quantum Monte Carlo (CT-HYB) is a popular approach in real material researches because it allows to deal with non-density-density-type interaction. In the conventional CT-HYB, we measure Green's function and find the self energy from the Dyson equation. Because one needs to compute the inverse of the statistical data in this approach, obtained self energy is very sensitive to statistical noise. For that reason, the measurement is not reliable except for low frequencies. Such an error can be suppressed by measuring a special type of higher-order correlation function and is implemented for density-density-type interaction. With the help of the recently reported worm-sampling measurement, we developed an improved self energy measurement scheme which can be applied to any type of interactions. As an illustration, we calculated the self energy for the 3-orbital Hubbard-Kanamori-type Hamiltonian with our newly developed method. This work was supported by NRF of Korea (Grant No. 2011-0018306) and KISTI supercomputing center (Project No. KSC-2015-C3-039)

  10. Cotton Leaf worm: Inherited Effects of Low Doses of Gamma Radiation on The Progeny of Irradiated Males. Vol. 4

    International Nuclear Information System (INIS)

    Full grown male pupae of the cotton leaf worm, Spodoptera Littoralis (Boisd.) were gamma irradiated with low doses of 25, 50,75, and 100 Gy. The effects on reproduction, development and sex ratio were the biological aspects studied among P1, F1, F2, F3 generations. Fecundity of normal females mated with F1 or F2 males was significantly reduced for all doses. The F1 males were more sterile than their irradiated parental males, while F2 males were more fertile F1 males. Irradiation of P1 males did not clearly affect neither the percentage of mated females nor the average number of spermatophores per mated females among the individuals of P1, F1, F2, F3 generations. The percent of larvae surviving to the adult stage was gradually decreased by increasing dose to P1 male throughout the first three filial generation. The average larval and pupal durations were not affected among the progeny of P1 males for both males and females. The sex ratio among the progeny of irradiated males was nearly 1:1. 3 tabs

  11. Development of insect resistant maize plants expressing a chitinase gene from the cotton leaf worm, Spodoptera littoralis.

    Science.gov (United States)

    Osman, Gamal H; Assem, Shireen K; Alreedy, Rasha M; El-Ghareeb, Doaa K; Basry, Mahmoud A; Rastogi, Anshu; Kalaji, Hazem M

    2015-01-01

    Due to the importance of chitinolytic enzymes for insect, nematode and fungal growth, they are receiving attention concerning their development as biopesticides or chemical defense proteins in transgenic plants and as microbial biocontrol agents. Targeting chitin associated with the extracellular matrices or cell wall by insect chitinases may be an effective approach for controlling pest insects and pathogenic fungi. The ability of chitinases to attack and digest chitin in the peritrophic matrix or exoskeleton raises the possibility to use them as insect control method. In this study, an insect chitinase cDNA from cotton leaf worm (Spodoptera littoralis) has been synthesized. Transgenic maize plant system was used to improve its tolerance against insects. Insect chitinase transcripts and proteins were expressed in transgenic maize plants. The functional integrity and expression of chitinase in progenies of the transgenic plants were confirmed by insect bioassays. The bioassays using transgenic corn plants against corn borer (Sesamia cretica) revealed that ~50% of the insects reared on transgenic corn plants died, suggesting that transgenic maize plants have enhanced resistance against S. cretica. PMID:26658494

  12. New observations of the lobopod-like worm Facivermis from the Early Cambrian Chengjiang Lagerst(a)tte

    Institute of Scientific and Technical Information of China (English)

    LIU Jianni; HAN Jian; SIMONETTA A. M.; HU Shixue; ZHANG Zhifei; YAO Yang; SHU Degan

    2006-01-01

    Facivermis yunnanicus (Hou & Chen, 1989), from the Early Cambrian Chengjiang Lagerst(a)tte, a worm-like fossil with 5 pairs of tentacles and a perceived shrunken end, has been regarded as related to polychaetes, later it has been variously interpreted as lobopods, Pentastoma and lophophorates. Newly discovered complete specimens by the ELI field team show that the taxon has, in addition to the 5 pairs of appendages, a pear-shaped trunk end bearing two or three circles of hooks. Accordingly, based on these important morphological characters, reconsideration of its affinities is provided and the taxonomy is remedied herein. Because the five pairs of appendages of Facivermis yunnanicus resemble the appendages of the fore-trunk of lobopod Miraluolishania (Liu & Shu, 2004), it seems that they are homologous structures. Therefore, the affinities of Facivermis are regarded here as being close to the lobopods, in addition, the lobe-like appendages of Facivermis are very crucial to exploring the origin of the appendages of lobopods and arthropods.

  13. Got worms? Perinatal exposure to helminths prevents persistent immune sensitization and cognitive dysfunction induced by early-life infection.

    Science.gov (United States)

    Williamson, Lauren L; McKenney, Erin A; Holzknecht, Zoie E; Belliveau, Christine; Rawls, John F; Poulton, Susan; Parker, William; Bilbo, Staci D

    2016-01-01

    The incidence of autoimmune and inflammatory diseases has risen dramatically in post-industrial societies. "Biome depletion" - loss of commensal microbial and multicellular organisms such as helminths (intestinal worms) that profoundly modulate the immune system - may contribute to these increases. Hyperimmune-associated disorders also affect the brain, especially neurodevelopment, and increasing evidence links early-life infection to cognitive and neurodevelopmental disorders. We have demonstrated previously that rats infected with bacteria as newborns display life-long vulnerabilities to cognitive dysfunction, a vulnerability that is specifically linked to long-term hypersensitivity of microglial cell function, the resident immune cells of the brain. Here, we demonstrate that helminth colonization of pregnant dams attenuated the exaggerated brain cytokine response of their offspring to bacterial infection, and that combined with post-weaning colonization of offspring with helminths (consistent with their mothers treatment) completely prevented enduring microglial sensitization and cognitive dysfunction in adulthood. Importantly, helminths had no overt impact on adaptive immune cell subsets, whereas exaggerated innate inflammatory responses in splenic macrophages were prevented. Finally, helminths altered the effect of neonatal infection on the gut microbiome; neonatal infection with Escherichia coli caused a shift from genera within the Actinobacteria and Tenericutes phyla to genera in the Bacteroidetes phylum in rats not colonized with helminths, but helminths attenuated this effect. In sum, these data point toward an inter-relatedness of various components of the biome, and suggest potential mechanisms by which this helminth might exert therapeutic benefits in the treatment of neuroinflammatory and cognitive disorders. PMID:26162711

  14. Synthesis of PbTe nanocubes, worm-like structures and nanoparticles by simple thermal evaporation method

    Indian Academy of Sciences (India)

    L Kungumadevi; R Sathyamoorthy

    2013-10-01

    Nanocrystalline PbTe thin films are prepared by thermal evaporation on glass substrates. The investigations of X-ray diffractograms have shown that the structure of film is found to possess stable face centred cubic (fcc) phase in which the grains predominantly grow in the direction of (200) plane. The grain size of the films is within the range of 27–43 nm. Morphologies like assembly of nanoparticles, worm-like structures and nanocubes were prepared by tuning the film thickness. Electrical resistivity is measured using four-probe technique and its thickness dependence has been analysed on the basis of ‘effective mean free path model’. A change in conductivity from -type to -type is observed due to the increase of migration of tellurium vacancies in the films with temperature. Bandgap energy of the PbTe nanocrystalline thin films suffered a large blue shift of about 1.299 eV due to quantum confinement of charge carriers. The nanocrystalline PbTe thin films of different morphologies such as nanoparticles, wormlike and nanocubes have the optical bandgap energies of 1.61, 1.23 and 1.01 eV, respectively. Photoconductivity measurement shows that the prepared nanocrystalline PbTe thin films of different morphology exhibits good response. This structure induced change in optical properties may have potential applications in optoelectronics devices.

  15. WORM memory devices based on conformation change of a PVK derivative with a rigid spacer in side chain

    International Nuclear Information System (INIS)

    A nonvolatile write-once-read-many-times (WORM) memory device based on poly((4-vinylbenzyl)-9H-carbazole) (PVCz) was fabricated by a simple and conventional process. The as-fabricated device was found to be at its OFF state and could be programmed irreversibly to the ON state with a low transition voltage of -1.7 V. The device exhibits a high ON/OFF current ratio of up to 106, high stability in retention time up to 8 h and number of read cycles up to 108 under a read voltage of -1.0 V in both ON and OFF states. The results of X-ray diffraction (XRD) and fluorescence emission spectra in different states of PVCz indicate that the electrical bistable phenomenon is caused by the voltage-induced conformation change of the pendant carbazole groups. With high performance, low power consumption and low production cost, the device fabricated with PVCz has a potential application for nonvolatile memory.

  16. Comparison of marine sediment toxicity test protocols for the amphipod Rhepoxynius abronius and the polychaete worm Nereis (Neanthes) arenaceodentata

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, B.S.; Hunt, J.W.; Phillips, B.M. [Univ. of California, Santa Cruz, CA (United States). Inst. of Marine Sciences]|[Marine Pollution Studies Lab., Monterey, CA (United States)] [and others

    1998-05-01

    The 10-d amphipod survival toxicity test protocol using Rhepoxynius abronius was compared to the 20-d polychaete worm growth and survival protocol using Nereis (Neanthes) arenaceodentata. Of the 341 sediment samples collected in California and tested over a 2-year period. 78% significantly inhibited R. abronius survival, whereas 2 and 26% significantly inhibited N. arenaceodentata survival and biomass, respectively. Statistical power associated with each protocol endpoint was determined by calculating the minimum significant difference (MSD) for each test protocol for this data set. The 90th percentile MSDs for R. abronius survival and N. arenaceodentata survival and biomass were 16, 36, and 56%, respectively. Survival of R. abronius was significantly negatively correlated with a number of toxicants including metals, pesticides, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls. No significant correlations were determined between N. arenaceodentata survival or biomass and contaminants measured. Amphipod survival was also negatively correlated with sediment total organic carbon and grain size, but when samples with a high percent fine grain size (>90% fines) were eliminated from consideration, the overall conclusions of the study were not altered. The 10-d amphipod survival protocol using R. abronius was a more sensitive indicator of toxicity, but the results indicate that this was due to greater statistical power rather than greater sensitivity of the test organisms or endpoints.

  17. Feasibility study of using a Zener diode as the selection device for bipolar RRAM and WORM memory arrays

    International Nuclear Information System (INIS)

    Cross-bar arrays are usually used for the high density application of resistive random access memory (RRAM) devices. However, cross-talk interference limits an increase in the integration density. In this paper, the Zener diode is proposed as a selection device to suppress the sneak current in bipolar RRAM arrays. Measurement results show that the Zener diode can act as a good selection device, and the sneak current can be effectively suppressed. The readout margin is sufficiently improved compared to that obtained without the selection device. Due to the improvement for the reading disturbance, the size of the cross-bar array can be enhanced to more than 103 × 103. Furthermore, the possibility of using a write-once-read-many-times (WORM) cross-bar array is also demonstrated by connecting the Zener diode and the bipolar RRAM in series. These results strongly suggest that using a Zener diode as a selection device opens up great opportunities to realize high density bipolar RRAM arrays. (paper)

  18. Is our Universe finite? New physics by dark matter. On hike through black, white, and worm holes

    International Nuclear Information System (INIS)

    Quantum Gravity (QG) allows finite-dimensional representations for its particles without getting into the traditional trouble with probability conservation. As in QG a particle and a universe are described by identical equations, our universe is expected to be finite, as well. Within a finite universe, not only space-time is limited, but there also must exist upper bounds for energy-momentum: A particle cannot be accelerated up to arbitrary energy. By erasing major inconsistencies in quantum field theories, their current types are proved to systematically destroying structure of our universe, which, thus, must be much greater than officially assumed. The key is traced back to Dark Matter. Black Holes are argued to be ''particle vertices'' with respect to our universe, while ''White Holes'', here, are not yet identified. The intermediary exchange state between such a related pair, by GR is represented as a ''Worm Hole''. For more information on QG and GUT see www.q-grav.com.

  19. Evaluating the Utility of Single-Locus DNA Barcoding for the Identification of Ribbon Worms (Phylum Nemertea).

    Science.gov (United States)

    Sundberg, Per; Kvist, Sebastian; Strand, Malin

    2016-01-01

    Whereas many nemerteans (ribbon worms; phylum Nemertea) can be identified from external characters if observed alive, many are still problematic. When it comes to preserved specimens (as in e.g. marine inventories), there is a particular need for specimen identifier alternatives. Here, we evaluate the utility of COI (cytochrome c oxidase subunit I) as a single-locus barcoding gene. We sequenced, data mined, and compared gene fragments of COI for 915 individuals representing 161 unique taxonomic labels for 71 genera, and subjected different constellations of these to both distance-based and character-based DNA barcoding approaches, as well as species delimitation analyses. We searched for the presence or absence of a barcoding gap at different taxonomic levels (phylum, subclass, family and genus) in an attempt to understand at what level a putative barcoding gap presents itself. This was performed both using the taxonomic labels as species predictors and using objectively inferred species boundaries recovered from our species delimitation analyses. Our data suggest that COI works as a species identifier for most groups within the phylum, but also that COI data are obscured by misidentifications in sequence databases. Further, our results suggest that the number of predicted species within the dataset is (in some cases substantially) higher than the number of unique taxonomic labels-this highlights the presence of several cryptic lineages within well-established taxa and underscores the urgency of an updated taxonomic backbone for the phylum. PMID:27171471

  20. Worm algorithm and diagrammatic Monte Carlo: A new approach to continuous-space path integral Monte Carlo simulations

    International Nuclear Information System (INIS)

    A detailed description is provided of a new worm algorithm, enabling the accurate computation of thermodynamic properties of quantum many-body systems in continuous space, at finite temperature. The algorithm is formulated within the general path integral Monte Carlo (PIMC) scheme, but also allows one to perform quantum simulations in the grand canonical ensemble, as well as to compute off-diagonal imaginary-time correlation functions, such as the Matsubara Green function, simultaneously with diagonal observables. Another important innovation consists of the expansion of the attractive part of the pairwise potential energy into elementary (diagrammatic) contributions, which are then statistically sampled. This affords a complete microscopic account of the long-range part of the potential energy, while keeping the computational complexity of all updates independent of the size of the simulated system. The computational scheme allows for efficient calculations of the superfluid fraction and off-diagonal correlations in space-time, for system sizes which are orders of magnitude larger than those accessible to conventional PIMC. We present illustrative results for the superfluid transition in bulk liquid 4He in two and three dimensions, as well as the calculation of the chemical potential of hcp 4He

  1. Genetic polymorphism of the beta-tubulin gene of Onchocerca volvulus in ivermectin naive patients from Cameroon, and its relationship with fertility of the worms

    OpenAIRE

    Bourguinat, C.; Pion, Sébastien; Kamgno, J.; Gardon, Jacques; Gardon Wendel, N.; Duke, B.O.L.; Prichard, R. K.; Boussinesq, Michel

    2006-01-01

    Observations of low response of patients infected with Onchocerca volvulus to ivermectin suggest that the parasite may be tinder a selection process toward potential resistance. To limit the extension of this phenomenon, it is crucial to characterize the genes of O. volvulus that are involved. For this, O. volvulus adult worms collected before the introduction of ivermectin in an onchocerciasis endemic area of central Cameroon were genotyped for beta-tubulin. To derive a baseline to investiga...

  2. Nucleic Acid Vaccination with Schistosoma mansoni Antioxidant Enzyme Cytosolic Superoxide Dismutase and the Structural Protein Filamin Confers Protection against the Adult Worm Stage

    OpenAIRE

    Cook, Rosemary M.; Carvalho-Queiroz, Claudia; Wilding, Gregory; Philip T. LoVerde

    2004-01-01

    Schistosomiasis remains a worldwide endemic cause of chronic and debilitating illness. There are two paradigms that exist in schistosome immunology. The first is that the schistosomule stages are the most susceptible to immune killing, and the second is that the adult stage, through evolution of defense mechanisms, can survive in the hostile host environment. One mechanism that seems to aid the adult worm in evading immune killing is the expression of antioxidant enzymes to neutralize the eff...

  3. Prevalence and risk factors associated with worm infestation in pre-school children (6-23 months) in selected blocks of Uttar Pradesh and Jharkhand, India

    OpenAIRE

    Awasthi S; Verma T; Kotecha P; Venkatesh V; Joshi V; Roy S

    2008-01-01

    Background :Intestinal worm infestation is widely prevalent in developing countries and can result in impaired nutrition and development. Aims: To estimate prevalence of and risk factors for intestinal geohelminths and other intestinal parasites in children aged 6 to 23 months. Settings and Design: Cross sectional study in rural India. Materials and Methods: Proportionate population size sampling method was used to randomly select 15 villages per block. Thereafter, house-to-house survey was d...

  4. A Diverse Community of Metal(loid) Oxide Respiring Bacteria Is Associated with Tube Worms in the Vicinity of the Juan de Fuca Ridge Black Smoker Field

    OpenAIRE

    Maltman, Chris; Walter, Graham; Yurkov, Vladimir

    2016-01-01

    Epibiotic bacteria associated with tube worms living in the vicinity of deep sea hydrothermal vents of the Juan de Fuca Ridge in the Pacific Ocean were investigated for the ability to respire anaerobically on tellurite, tellurate, selenite, selenate, metavanadate and orthovanadate as terminal electron acceptors. Out of 107 isolates tested, 106 were capable of respiration on one or more of these oxides, indicating that metal(loid) oxide based respiration is not only much more prevalent in natu...

  5. Mechanism of Fluorescence and Conformational Changes of the Sarcoplasmic Calcium Binding Protein of the Sand Worm Nereis diversicolor upon Ca2+ or Mg2+ Binding

    OpenAIRE

    Sillen, Alain; Verheyden, Stefan; Delfosse, Lotte; Braem, Tania; Robben, Johan; Volckaert, Guido; Engelborghs, Yves

    2003-01-01

    The calcium-binding protein isolated from the sarcoplasm of the muscles of the sand worm Nereis diversicolor has four EF-hands and three active binding sites for Ca2+ or Mg2+. Nereis diversicolor sarcoplasmic calcium-binding protein contains three tryptophan residues at positions 4, 57, and 170, respectively. The Wt protein shows a very limited fluorescence increase upon binding of Ca2+ or Mg2+. Single-tryptophan-containing mutants were produced and purified. The fluorescence titrations of th...

  6. 基于ANSYS Workbench 14.0平面二包环面蜗轮蜗杆副的有限元分析%Finite Element Analysis of Planar Quadratic Enveloping Torus Worm Gear and Worm Pair Based on ANSYS Workbench 14.0

    Institute of Scientific and Technical Information of China (English)

    付大鹏; 孙文杰

    2016-01-01

    利用ANSYS Workbench 14.0对平面二次包络环面蜗轮蜗杆副进行静力学有限元分析,并对其齿间载荷分布以及载荷延接触线方向的分配情况进行研究,通过与其理论数据进行对比,验证平面二次包络环面蜗轮蜗杆副数字建模的准确性.%Using ANSYS Workbench 14.0, static finite element analysis of the planar quadratic enveloping torus worm gear and worm pair is carried out in this paper, and the load distribution among gear teeth and load distribution of contact line direction are re-searched as well. With its theoretical data model, the accuracy of digital modeling for plane quadratic enveloping ring surface worm gear and worm pair is verified.

  7. Research on Shaping Quality of Compensation Cushion of Worm Speed Reducer%关于蜗轮减速器补偿垫成形质量的研究

    Institute of Scientific and Technical Information of China (English)

    李雪梅

    2014-01-01

    蜗轮减速器补偿垫采用聚氨酯橡胶冲模加工,该模具设计结构紧凑、拆装方便、制造简单,冲裁出的多种规格的补偿垫零件平整、成形一致、毛刺小、严格控制了蜗轮、蜗杆的补偿间隙,使蜗轮副转动灵活。%Compensation cushion of worm speed reducer was used polyurethane rubber punch die processing. The structure of mould has features of convenient tear open outfit, simple manufacturing, cutting out a variety of specifications of the com-pensating cushion flat parts, forming small, burr, strictly control the worm gear and worm compensation gap, which make ro-tation of worm gear pair flexible.

  8. ZA型蜗杆成形磨削技术研究%Study on the form grinding technology of ZA-worm

    Institute of Scientific and Technical Information of China (English)

    张彦坤; 李志峰; 赵永强

    2013-01-01

    针对阿基米德蜗杆(ZA型蜗杆)磨削加工的要求,建立了阿基米德蜗杆磨削加工的数学模型,根据CNC砂轮修整器的成形原理,推导了磨削用砂轮截形的计算方法,利用MATLAB计算得到砂轮回转面的截形,在带有CNC砂轮修整器的数控螺纹磨床上实现了蜗杆的磨削试验.试验证明,该方法稳定提升了蜗杆的磨削精度,而且操作简单.%Considering the requirements of grinding machining of archimedes worm (ZA-worm), the mathematical model of processing archimedes worms has been established. The grinding wheel section equation has been deduced based on the form grinding principle of CNC (computerized numerical control). Grinding wheel dresser and the grinding wheel's revolution surface has been calculated by MATLAB programs. In the paper, the experiment has been done on a grinder with a CNC grinding wheel dresser. It shows that the accuracy is improved and operation is easier by using the method.

  9. Purification of a chymotrypsin-like enzyme present on adult Schistosoma mansoni worms from infected mice and its characterization as a host carboxylesterase.

    Science.gov (United States)

    Igetei, Joseph E; Liddell, Susan; El-Faham, Marwa; Doenhoff, Michael J

    2016-04-01

    A serine protease-like enzyme found in detergent extracts of Schistosoma mansoni adult worms perfused from infected mice has been purified from mouse blood and further characterized. The enzyme is approximately 85 kDa and hydrolyses N-acetyl-DL-phenylalanine β-naphthyl-ester, a chromogenic substrate for chymotrypsin-like enzymes. The enzyme from S. mansoni worms appears to be antigenically and enzymatically similar to a molecule that is present in normal mouse blood and so is seemingly host-derived. The enzyme was partially purified by depleting normal mouse serum of albumin using sodium chloride and cold ethanol, followed by repeated rounds of purification by one-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis. The purified material was subjected to tandem mass spectrometry and its derived peptides found to belong to mouse carboxylesterase 1C. Its ability to hydrolyse α- or β-naphthyl acetates, which are general esterase substrates, has been confirmed. A similar carboxylesterase was purified and characterized from rat blood. Additional evidence to support identification of the enzyme as a carboxylesterase has been provided. Possible roles of the enzyme in the mouse host-parasite relationship could be to ease the passage of worms through the host's blood vessels and/or in immune evasion. PMID:26924446

  10. Effectiveness of hyperbaric oxygen for experimental treatment of schistosomiasis mansoni using praziquantel-free and encapsulated into liposomes: assay in adult worms and oviposition.

    Science.gov (United States)

    Frezza, Tarsila Ferraz; de Souza, Ana Luiza Ribeiro; Prado, César Corat Ribeiro; de Oliveira, Claudineide Nascimento Fernandes; Gremião, Maria Palmira Daflon; Giorgio, Selma; Dolder, Mary Anne Heidi; Joazeiro, Paulo Pinto; Allegretti, Silmara Marques

    2015-10-01

    The treatment of schistosomiasis depends on a single drug: praziquantel (PZQ). However, this treatment presents limitations such as low and/or erratic bioavailability that can contribute to cases of tolerance. Improvements to the available drug are urgently needed and studies with a controlled system of drug release, like liposomes, have been gaining prominence. The present study evaluated the activity and synergy between liposomal-praziquantel (lip.PZQ) and hyperbaric oxygen therapy (HBO). Mice received doses of 60 or 100mg/kg PZQ or lip.PZQ, 50 days post-infection, and after the treatment, were exposed to HBO (3 atmosphere absolute - ATA) for 1h. The viability of adult worms and oviposition were analyzed, by necropsy and Kato-Katz examination performed after 15 days of treatment. A concentration of 100mg/kg of lip.PZQ+HBO was more effective (48.0% reduction of worms, 83.3% reduction of eggs/gram of feces) and 100% of the mice had altered of oograms (indicating interruption of oviposition) compared to other treatments and to the Control group (infected and untreated). It is known that PZQ requires participation of the host immune system to complete its antischistosomal activity and that HBO is able to stimulate the immune system. The drug became more available in the body when incorporated into liposomes and, used with HBO, the HBO worked as an adjuvant. This explains the decreases of oviposition and worms recovered form hepatic portal system. PMID:26215128

  11. A Diverse Community of Metal(loid) Oxide Respiring Bacteria Is Associated with Tube Worms in the Vicinity of the Juan de Fuca Ridge Black Smoker Field.

    Science.gov (United States)

    Maltman, Chris; Walter, Graham; Yurkov, Vladimir

    2016-01-01

    Epibiotic bacteria associated with tube worms living in the vicinity of deep sea hydrothermal vents of the Juan de Fuca Ridge in the Pacific Ocean were investigated for the ability to respire anaerobically on tellurite, tellurate, selenite, selenate, metavanadate and orthovanadate as terminal electron acceptors. Out of 107 isolates tested, 106 were capable of respiration on one or more of these oxides, indicating that metal(loid) oxide based respiration is not only much more prevalent in nature than is generally believed, but also is an important mode of energy generation in the habitat. Partial 16S rRNA gene sequencing revealed the bacterial community to be rich and highly diverse, containing many potentially new species. Furthermore, it appears that the worms not only possess a close symbiotic relationship with chemolithotrophic sulfide-oxidizing bacteria, but also with the metal(loid) oxide transformers. Possibly they protect the worms through reduction of the toxic compounds that would otherwise be harmful to the host. PMID:26914590

  12. Biomonitoring in a clean and a multi-contaminated estuary based on biomarkers and chemical analyses in the endobenthic worm Nereis diversicolor

    Energy Technology Data Exchange (ETDEWEB)

    Durou, Cyril [CNRS, Universite de Nantes, Pole Mer et Littoral, SMAB, 2 rue de la Houssiniere, BP 92208, F-44322 Nantes Cedex 3 (France) and Institut de Biologie et Ecologie Appliquees, CEREA, Universite Catholique de l' Ouest, 44 rue Rabelais, 49008 Angers Cedex 01 (France)]. E-mail: cyril.durou@uco.fr; Poirier, Laurence [CNRS, Universite de Nantes, Pole Mer et Littoral, SMAB, 2 rue de la Houssiniere, BP 92208, F-44322 Nantes Cedex 3 (France); Amiard, Jean-Claude [CNRS, Universite de Nantes, Pole Mer et Littoral, SMAB, 2 rue de la Houssiniere, BP 92208, F-44322 Nantes Cedex 3 (France); Budzinski, Helene [CNRS UMR 5472, LPTC, Universite de Bordeaux I, 33405 Talence (France); Gnassia-Barelli, Mauricette [UMR INRA UNSA 1112 ROSE, Faculte des Sciences, BP 71, 06108 Nice Cedex 2 (France); Lemenach, Karyn [CNRS UMR 5472, LPTC, Universite de Bordeaux I, 33405 Talence (France); Peluhet, Laurent [CNRS UMR 5472, LPTC, Universite de Bordeaux I, 33405 Talence (France); Mouneyrac, Catherine [CNRS, Universite de Nantes, Pole Mer et Littoral, SMAB, 2 rue de la Houssiniere, BP 92208, F-44322 Nantes Cedex 3 (France); Institut de Biologie et Ecologie Appliquees, CEREA, Universite Catholique de l' Ouest, 44 rue Rabelais, 49008 Angers Cedex 01 (France); Romeo, Michele [UMR INRA UNSA 1112 ROSE, Faculte des Sciences, BP 71, 06108 Nice Cedex 2 (France); Amiard-Triquet, Claude [CNRS, Universite de Nantes, Pole Mer et Littoral, SMAB, 2 rue de la Houssiniere, BP 92208, F-44322 Nantes Cedex 3 (France)

    2007-07-15

    Relationships between biochemical and physiological biomarkers (acetylcholinesterase [AChE], catalase, and glutathione S-transferase [GST] activities, thiobarbituric acid reactive substances, glycogen, lipids and proteins) and accumulated concentrations of contaminants (polychlorinated biphenyls [PCBs], polycyclic aromatic hydrocarbons and metals) were examined in the keystone species Nereis diversicolor. The chemical analyses of worms and sediments allowed the designation of the Seine estuary and the Authie estuary as a polluted and relatively clean site respectively. Worms from the Seine estuary exhibited higher GST and lower AChE activities. Generally, larger worms had higher concentrations of energy reserves. Principal component analyses clearly highlighted intersite differences: in the first plan, GST activities and chemical concentrations were inversely related to concentrations of energy reserves; in the second one, PCB concentrations and AChE activity were inversely related. Depleted levels of energy reserves could be a consequence of combating toxicants and might predict effects at higher levels of biological organization. The use of GST and AChE activities and energy reserve concentrations as biomarkers is validated in the field in this keystone species. - The use of N. diversicolor as a biomonitor of environmental quality via the measurement of biomarkers and accumulated concentrations of contaminants is validated in the field.

  13. Biomonitoring in a clean and a multi-contaminated estuary based on biomarkers and chemical analyses in the endobenthic worm Nereis diversicolor

    International Nuclear Information System (INIS)

    Relationships between biochemical and physiological biomarkers (acetylcholinesterase [AChE], catalase, and glutathione S-transferase [GST] activities, thiobarbituric acid reactive substances, glycogen, lipids and proteins) and accumulated concentrations of contaminants (polychlorinated biphenyls [PCBs], polycyclic aromatic hydrocarbons and metals) were examined in the keystone species Nereis diversicolor. The chemical analyses of worms and sediments allowed the designation of the Seine estuary and the Authie estuary as a polluted and relatively clean site respectively. Worms from the Seine estuary exhibited higher GST and lower AChE activities. Generally, larger worms had higher concentrations of energy reserves. Principal component analyses clearly highlighted intersite differences: in the first plan, GST activities and chemical concentrations were inversely related to concentrations of energy reserves; in the second one, PCB concentrations and AChE activity were inversely related. Depleted levels of energy reserves could be a consequence of combating toxicants and might predict effects at higher levels of biological organization. The use of GST and AChE activities and energy reserve concentrations as biomarkers is validated in the field in this keystone species. - The use of N. diversicolor as a biomonitor of environmental quality via the measurement of biomarkers and accumulated concentrations of contaminants is validated in the field

  14. Biomonitoring in a clean and a multi-contaminated estuary based on biomarkers and chemical analyses in the endobenthic worm Nereis diversicolor.

    Science.gov (United States)

    Durou, Cyril; Poirier, Laurence; Amiard, Jean-Claude; Budzinski, Hélène; Gnassia-Barelli, Mauricette; Lemenach, Karyn; Peluhet, Laurent; Mouneyrac, Catherine; Roméo, Michèle; Amiard-Triquet, Claude

    2007-07-01

    Relationships between biochemical and physiological biomarkers (acetylcholinesterase [AChE], catalase, and glutathione S-transferase [GST] activities, thiobarbituric acid reactive substances, glycogen, lipids and proteins) and accumulated concentrations of contaminants (polychlorinated biphenyls [PCBs], polycyclic aromatic hydrocarbons and metals) were examined in the keystone species Nereis diversicolor. The chemical analyses of worms and sediments allowed the designation of the Seine estuary and the Authie estuary as a polluted and relatively clean site respectively. Worms from the Seine estuary exhibited higher GST and lower AChE activities. Generally, larger worms had higher concentrations of energy reserves. Principal component analyses clearly highlighted intersite differences: in the first plan, GST activities and chemical concentrations were inversely related to concentrations of energy reserves; in the second one, PCB concentrations and AChE activity were inversely related. Depleted levels of energy reserves could be a consequence of combating toxicants and might predict effects at higher levels of biological organization. The use of GST and AChE activities and energy reserve concentrations as biomarkers is validated in the field in this keystone species. PMID:17289233

  15. Partial characterization of superoxide dismutase activity in the Barber pole worm-Haemonchus contortus infecting Capra hircus and abomasal tissue extracts

    Institute of Scientific and Technical Information of China (English)

    Sadia; Rashid; Malik; Irshadullah

    2014-01-01

    Objective:To determine the activity of superoxide dismutase(SOD) in the male and female haematophagous caprine worms,Haemonchus contortus infecting Capra hircus,and their E/S products and also to analyse the effect of Haemonchus infection on the level of host SOD.Methods:The SOD activity was analysed by using the pyrogallol autoxidation assay and non-denaturing polyacrylamide gel electrophoresis followed by specific enzyme staining by riboflavin-nitroblue tetrazolium method.Results:The adult females were found to have higher enzyme activity than the male worms.Appreciable amount of SOD activity was also detected in the worm culture medium and female worms secreted more SOD in comparison to the male parasites.The SOD activity was negatively correlated to the worm burden.Statistically significant decrease in SOD activity(P<0.05) was observed in the heavily infected host tissue in comparison to the control non-infected host tissue.SOD profile of the crude extracts of both the sexes revealed polymorphism and a fast migrating activity band being characteristic of E/S products.The SOD activities were found highly sensitive to potassium cyanide indicating the Cu/Zn form of SOD.Conclusions:Haemonchus contortus is a key model parasite for drug and vaccine discovery.The presences of SOD activity in appreciable amount in the parasite as well as its E/S products indicate that it has a well-developed active antioxidant system to protect itself from the host immune attack.SOD could be the target for vaccine development which is the need of the hour as mass drug administration for parasite control has resulted in anthelmintic resistance across the globe and threatens the viability of sheep and goat industry in many regions of the world.The infection with Haemonchus causes a drastic reduction in SOD activity of the host tissue thus effecting its protective potential.One characteristic SOD band was found in the females which was not present in any other preparations and thus could

  16. First occurrence of western corn root worm beetles in the federal states Hesse and Rhineland-Palatinate (Germany, 2011

    Directory of Open Access Journals (Sweden)

    Dicke, Dominik

    2014-02-01

    Full Text Available In 2011, western corn root worm beetles were detected in the federal states Hesse (Groß-Gerau and Rhineland-Palatinate (Bodenheim for the first time. Control measures based on commission decision 2003/766/EG (Byrne, 2003 were conducted after detection in PAL-traps. Focus and safety zones were established. In Hesse, both focus and safety zones were treated with the insecticide Biscaya, due to the high number of 50 beetles which were detected in the PAL-traps. Since in Rhineland-Palatinate, only one beetle had been captured, only the focus zone was treated with the insecticide. After insecticide treatment, new PAL-traps were arranged like a close grid over the infested areas in both federal states. In each maize field in the focus- and safety zone further traps were placed and checked weekly until September 30th by supporting staff. Until the end of the monitoring in 2011 (September 30th further beetles were detected in the south of the area (district of Groß-Gerau, Hesse, were the first infestation had been discovered. However, in Rhineland-Palatinate no further beetles were detected that year. By the end of the monitoring 354 beetles in Hesse and one beetle in Rhineland-Palatinate had been captured in total. Subsequently the demarked zones in Hesse were extended. Taking into account the local circumstances, the new focus zone was delimited to include all the areas where beetles had been detected as well as the surrounding maize fields. In the focus zones the cultivation of maize was forbidden for the consecutive two years and a crop rotation with at least 50 percent maize was established in the safety zones. In 2012 no further beetles were captured in the infested region.

  17. Ontogenetic allometry constrains cranial shape of the head-first burrowing worm lizard Cynisca leucura (Squamata: Amphisbaenidae).

    Science.gov (United States)

    Hipsley, Christy A; Rentinck, Marc-Nicolas; Rödel, Mark-Oliver; Müller, Johannes

    2016-09-01

    Amphisbaenians are fossorial, predominantly limbless squamate reptiles with distinct cranial shapes corresponding to specific burrowing behaviors. Due to their cryptic lifestyles and the scarcity of museum specimens, little is known of their intraspecific variation, particularly regarding cranial osteology. This represents a critical lack of information, because the majority of morphological investigations of squamate relationships are based on cranial characters. We investigated cranial variation in the West African Coast Worm Lizard Cynisca leucura, a round-headed member of the Amphisbaenidae. Using geometric morphometric analyses of three-dimensional computed tomographic scans, we found that cranial osteology of C. leucura is highly conserved, with the majority of shape changes occurring during growth as the cranium becomes more slender and elongate, accompanied by increasing interdigitation among the dermal roofing bones. Elements of the ventral portion of the cranium remain loosely connected in adults, possibly as a protective mechanism against repeated compression and torsion during burrow excavation. Intraspecific variation was strongly correlated with size change from juveniles to adults, indicating a dominant role of ontogenetic allometry in determining cranial shape. We found no evidence of sexual dimorphism, either during growth or among adults. Given the fossorial habits of C. leucura, we hypothesize that cranial allometry is under strong stabilizing selection to maintain adequate proportions for head-first digging, thereby constraining the ability of individuals to respond to differing selection pressures, including sexual selection and variation in diet or microhabitat. For species in which digging imposes less mechanical stress (e.g., in softer sand), allometric associations during growth may be weakened, allowing changes to the ontogenetic trajectory and subsequent morphological traits. Such developmental dissociation between size and shape, known

  18. Flooding modifies the genotoxic effects of pollution on a worm, a mussel and two fish species from the Sava River.

    Science.gov (United States)

    Aborgiba, Mustafa; Kostić, Jovana; Kolarević, Stoimir; Kračun-Kolarević, Margareta; Elbahi, Samia; Knežević-Vukčević, Jelena; Lenhardt, Mirjana; Paunović, Momir; Gačić, Zoran; Vuković-Gačić, Branka

    2016-01-01

    Extreme hydrological events, such as water scarcity and flooding, can modify the effect of other stressors present in aquatic environment, which could result in the significant changes in the ecosystem functioning. Presence and interaction of various stressors (genotoxic pollutants) in the environment can influence the integrity of DNA molecules in aquatic organisms which can be negatively reflected on the individual, population and community levels. Therefore, in this study we have investigated the impact of flooding, in terms of genotoxicity, on organisms belonging to different trophic levels. The study was carried out on the site situated in the lower stretch of the Sava River which faced devastating effects of severe flooding in May 2014. The flooding occurred during our field experiment and this event provided a unique opportunity to assess its influence to the environment. The in situ effects of this specific situation were monitored by measuring physical, chemical and microbiological parameters of water, and by comparing the level of DNA damage in coelomocytes and haemocytes of freshwater worms Branchiura sowerbyi, haemocytes of freshwater mussels Unio tumidus and blood cells of freshwater fish Abramis bjoerkna/Abramis sapa, by means of the comet assay. Our study indicated that the flooding had a significant impact on water quality by decreasing the amount and discharge rate of urban wastewaters but simultaneously introducing contaminants from the nearby fly ash disposal field into river by runoff, which had diverse effects on the level of DNA damage in the studied organisms. This indicates that the assessment of genotoxic pollution in situ is strongly affected by the choice of the bioindicator organism. PMID:25861862

  19. Studies on inherited sterility induced in the progeny of gamma irradiated cotton leaf worm, Spodoptera littorals (Boisd.)

    International Nuclear Information System (INIS)

    Full - grown pupae of the cotton leaf worm Spodoptera littorals (Boisd.) were gamma - irradiated with low doses of 25,50,75, or 100 Gy for male line and with 50 or 100 Gy for female line . The effects on reproduction, development and sex ratio were the biological aspects studied among P1,F1,F2 and F 3 generations . Also, the effects of dose accumulation applied grown male pupae through two or three filial generations and the retarded influence on their F1,F2,and F 3 progeny were examined. In another trial the histological examinations for ovaries and testes of irradiated parents and for their generation were made . The F1 males were more sterile than irradiated parental males while F1 females were more fertile than their irradiated parental females. Irradiation of P1 males did not clearly affect neither the percentage of mated females nor the average number of spermatophores per mated female among the individuals of P1,F1,F2 and F 3 generations. Irradiation of P1 females did not affect neither the percentage of mated females nor the percentage of inseminated females among P1 and their next three successive generations. The reduction in fecundity was highly correlated with both doses and number of accumulated doses. Males received two accumulated doses of 25 Gy through the two successive generations.(25 + 25 Gy) were more sterile than the males received the same two doses but at once as one acute dose of 50 Gy. The histological observations showed that the damage in the testes and ovaries was correlated with the increasing of the dose applied to the male parents and was the highest among the adults of F1. Also, the damage at any acute dose was less than the damage occurred in the same accumulated dose

  20. Radiation induced F1 sterility in diamondback moth, Plutella xylostella L., and tropical army worm, Spodoptera litura F

    International Nuclear Information System (INIS)

    A 300 Gy dose of gamma irradiation can be used as the sterilizing dose for the diamond-back moth (DBM). This caused 90% sterility of the moths. Releases of irradiated moths into the normal populations (nine irradiated to one normal) in laboratory cages, field cages and small field plots reduced the F1 population by 61, 55 and 42%, respectively. The effects of substerilizing doses of 175 and 200 Gy to the irradiated parents caused 26 and 36% sterilities, respectively. The dose of 175 Gy caused the levels of sterility of the male and female F1 progeny to be 54 and 74%, respectively, while the dose of 200 Gy caused 56% sterility of the F1 male and 71% of the F1 female. The sterility of the F2 population was nearly the same as that of the irradiated parents. At a radiation doses of 175 Gy the sterility of F2 males was about 11% and of females 37%. At a dose of 200 Gy the levels of sterility of the males and females were 9 and 14%, respectively. Gamma irradiation did not affect the fecundity of the irradiated parents or of the F1 and F2 progeny. The average number of eggs produced by one pair of DBM moths was 180. The viabilities of unirradiated pupae, irradiated parents, F1 and F2 at a dose of 200 Gy were 94, 89, 54 and 65%, respectively. The effect of releasing F1 sterile moths into untreated populations at a ratio of 45:1 could be a reduction in the population by 22%. Delta traps baited with the sex pheromone Sj showed the highest trapping efficiency. The highest population of DBMs in the dry season is in May and the lowest point is in July. The longevity of the tropical army worm was slightly affected by gamma irradiation. The dose of irradiation did not affect the viability of the pupae. A substerilizing dose of 100 Gy caused 43% parental sterility, 76% F1 sterility and 54% F2 sterility. (author). 7 refs, 3 figs, 8 tabs

  1. Identification of a transformer homolog in the acorn worm, Saccoglossus kowalevskii, and analysis of its activity in insect cells.

    Science.gov (United States)

    Suzuki, Masataka G; Tochigi, Mayuko; Sakaguchi, Honami; Aoki, Fugaku; Miyamoto, Norio

    2015-06-01

    The transformer (tra) gene is an intermediate component of the sex determination hierarchy in many insect species. The homolog of tra is also found in two branchiopod crustacean species but is not known outside arthropods. We have isolated a tra homolog in the acorn worm, Saccoglossus kowalevskii, which is a hemichordate belonging to the deuterostome superphylum. The full-length complementary DNA (cDNA) of the S. kowalevskii tra homolog (Sktra) has a 3786-bp open reading frame that encodes a 1261-amino acid sequence including a TRA-CAM domain and an arginine/serine (RS)-rich domain, both of which are characteristic of TRA orthologs. Reverse transcription PCR (RT-PCR) analyses demonstrated that Sktra showed no differences in expression patterns between testes and ovaries, but its expression level was approximately 7.5-fold higher in the testes than in the ovaries. TRA, together with the protein product of the transformer-2 (tra-2) gene, assembles on doublesex (dsx) pre-messenger RNA (mRNA) via the cis-regulatory element, enhancing female-specific splicing of dsx in Drosophila. To understand functional conservation of the SkTRA protein as a dsx-splicing activator, we investigated whether SkTRA is capable of inducing female-specific splicing of the Drosophila dsx. Ectopic expression of Sktra cDNA in insect cultured cells did not induce the female-specific splicing of dsx. On the other hand, forced expression of Sktra-2 (a tra-2 homolog of S. kowalevskii) was able to induce the female-specific dsx splicing. These results demonstrate that the function as a dsx-splicing activator is not conserved in SkTRA even though SkTRA-2 is capable of functionally replacing the Drosophila TRA-2. We have also found a tra homolog in an echinoderm genome. This study provides the first evidence that that tra is conserved not only in arthropods but also in basal species of deuterostoms. PMID:25868907

  2. From Spherical Mesopores to Worm-Shaped Mesopores: Morphology Transition in Titania-Polystyrene- b -poly(ethylene oxide) Composite Films with Increasing Sol-Gel Reaction Time

    OpenAIRE

    Cheng, Ya-Jun; Zhou, Shaoying; Gutmann, Jochen S; Wolkenhauer, Markus; Bumbu, Gina-Gabriela; Lenz, Sebastian; Memesa, Mine; Nett, Sebastian; Emmerling, Sebastian; Steffen, Werner; Roth, Stephan V.

    2014-01-01

    A morphology transition from spherical mesopores to worm-shaped mesopores within titania block copolymer composite thin films has been observed by varying the sol–gel reaction time from 40 min to 48 h in the four-component templating system of polystyrene-$\\mathit{b}$-poly(ethylene oxide) (PS-$\\mathit{b}$-PEO), 1,4-dioxane, concentrated HCl, and titanium tetraisopropoxide (TTIP) with a PS-$\\mathit{b}$-PEO mass concentration of 0.25 wt.-%. The impact of the sol–gel reaction time on the local s...

  3. Phytoplankton reduction in near-bottom water caused by filter-feeding Nereis diversicolor - Implications for worm growth and population grazing impact

    OpenAIRE

    Larsen, Poul Scheel; Riisgård, H.U.; Poulsen, L

    1996-01-01

    Studies of vertical profiles of phytoplankton in the field combined with laboratory experiments demonstrated that reduction in phytoplankton concentrations in the near-bottom water layer, 5 to 10 cm in thickness on calm days, may play a significant role for the filter-feeding polychaete Nereis diversicolor in realizing its grazing capacity (estimated at 13.8 m3 m-2 d-1 in the shallow bay of Kertinge Nor, Denmark, in July 1994). Field-growth experiments were performed with worms transferred to...

  4. Comparison of fecal examinations and worm collection results in an investigation of Ascaris lumbricoides infection%人群蛔虫感染调查粪检与驱虫结果比较

    Institute of Scientific and Technical Information of China (English)

    姜唯声; 曾小军; 李华忠; 陈颖丹; 洪献林; 胡神助; 兰炜明; 陈奕杨

    2012-01-01

    Objective To explore the relationship hetween fecal examinations and worm collection results in a community investigation of Ascaris lumbricoides infection. Methods A total of 1 019 residents in Zhangxi Village, Nanchang County, Jiangxi Province were investigated with the Kato-Katz technique and worm collection after deworming. Results Among 1 019 residents investigated, the actual prevalence of A. lumhricoides was 30.23%, and the egg and worm positive rates were 20.41 % and 23,75%, respectively. The average burden was 2.64 worms per person, and the heavier worm burden accounted for less proportion. The heavier the worm burden, the higher ihe probability to got egg in the feees. If one person had 7 worms or more, the probability to got eggs in his feces was 100%. Among people of false negative fecal examination, 61.00% of them were infected with male worms only, whereas 7.00% were infected with immature female worms with or without male worms, and 32.00% were infected with mature female worms with or without male worms. Totally 32.47% of infected people were missed by fecal examination, including 22.08% without egg excreted, and 10.39% missed because of the method itself. Conclusion The egg positive rate is obviously lower than the actual infection rate, and the egg detection rate is correlated with the worm burden.%目的 探讨社区人群蛔虫感染调查中粪检与驱虫结果的关系.方法 选择江西省南昌县塘南乡张溪村为试点,采用Kato-Katz法粪检,双羟萘噻嘧啶化疗驱虫后收集虫体,对两者结果进行比较分析.结果 共检测1019名村民,人群实际蛔虫感染率为30.23%,其中粪检阳性率为20.41%,淘虫阳性率为23.75%.淘虫阳性感染者平均虫荷2.64条,虫荷数高的感染者所占比例较低.感染者虫荷数越多,检出虫卵的概率越高,当感染者寄生7条以上蛔虫,虫卵检出率为100%.粪检虫卵假阴性者中,感染雄虫者占61.00%,感染雌虫

  5. Morphological aspects of Schistosoma mansoni adult worms isolated from nourished and undernourished mice: a comparative analysis by confocal laser scanning microscopy

    Directory of Open Access Journals (Sweden)

    Neves Renata Heisler

    2001-01-01

    Full Text Available Malnutrition hampers the course of schistosomiasis mansoni infection just as normal growth of adult worms. A comparative morphometric study on adult specimens (male and female recovered from undernourished (fed with a low protein diet - regional basic diet and nourished (rodent commercial laboratory food, NUVILAB white mice was performed. Tomographic images and morphometric analysis of the oral and ventral suckers, reproductive system and tegument were obtained by means of confocal laser scanning microscopy. Undernourished male specimens presented smaller morphometric values (length and width of the reproductive system (first, third and last testicular lobes and thickness of the tegument than controls. Besides that, it was demonstrated that the dorsal surface of the male worms bears large tubercles unevenly distributed, but kept grouped and flat. At the subtegumental region, vacuolated areas were detected. It was concluded that the inadequate nutritional status of the vertebrate host has a negative influence mainly in the reproductive system and topographical somatic development of male adult Schistosoma mansoni, inducing some alterations on the structure of the parasite.

  6. Reproductive system abnormalities in Schistosoma mansoni adult worms isolated from Nectomys squamipes (Muridae: Sigmodontinae: brightfield and confocal laser scanning microscopy analysis

    Directory of Open Access Journals (Sweden)

    Neves Renata Heisler

    2003-01-01

    Full Text Available Schistosoma mansoni adult worms with genital anomalies isolated from Nectomys squamipes (Muridae: Sigmodontinae were studied by confocal laser scanning microscopy under the reflected mode. One male without testicular lobes (testicular agenesia/anorchism and two females, one with an atrophied ovary and another with 17 uterine eggs, were identified. The absence of testicular lobes occurred in a worm presenting otherwise normal male adult characteristics: tegument, tubercles and a gynaecophoric canal with spines. In both female specimens the digestive tube showed a vacuolated appearance, and the specimen with supernumerary uterine eggs exhibited a developing miracidium and an egg with a formed shell. The area of the ventral sucker was similar in both specimens however the tegument thickness, ovary and vitelline glands of the specimen with the atrophied ovary were smaller than those of the one with supernumerary eggs. These reported anomalies in the reproductive system call attention to the need to improve our understanding of genetic regulation and the possible role of environmental influences upon trematode development.

  7. Worm-like mesoporous TiO2 thin films templated using comb copolymer for dye-sensitized solar cells with polymer electrolyte

    Science.gov (United States)

    Lee, Jae Hun; Park, Cheol Hun; Jung, Jung Pyo; Kim, Jong Hak

    2015-12-01

    A comb copolymer consisting of hydrophobic poly(2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl] ethyl methacrylate) (PBEM) and hydrophilic poly(oxyethylene methacrylate) (POEM) is synthesized via one-pot free radical polymerization. The PBEM-POEM comb copolymer is used as an agent to direct the structure toward one consisting of worm-like mesoporous TiO2 (WM-TiO2) films. The selective, preferential interaction between the titania precursor and the hydrophilic POEM chains is responsible for the formation of a well-organized worm-like mesostructure. The morphology of the WM-TiO2 films is characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). In particular, the effects of film thickness on the optical and electrochemical properties are systematically investigated. The introduction of the WM-TiO2 layer between the nanocrystalline TiO2 (NC-TiO2) layer and fluorine-doped tin oxide (FTO) glass results in increased transmittance of visible light due to an antireflective property, decreased interfacial resistance and suppressed charge recombination at the interfaces of NC-TiO2/FTO glass. As a result, the photovoltaic conversion efficiency of the dye-sensitized solar cell (DSSC) with a polymer electrolyte is improved from 5.3% to 6.6% at an optimum film thickness (310 nm). The obtained efficiency represents a higher efficiency for the N719-based DSSC with a solvent-free, polymer electrolyte.

  8. Sm14 gene expression in different stages of the Schistosoma mansoni life cycle and immunolocalization of the Sm14 protein within the adult worm

    Directory of Open Access Journals (Sweden)

    C.F.A. Brito

    2002-03-01

    Full Text Available Sm14 is a 14-kDa vaccine candidate antigen from Schistosoma mansoni that seems to be involved in cytoplasmic trafficking of fatty acids. Although schistosomes have a high requirement for lipids, they are not able to synthesize fatty acids and sterols de novo. Thus, they must acquire host lipids. In order to determine whether Sm14 is present in different stages of the life cycle of the parasite, we performed RT-PCR. Sm14 mRNA was identified in all stages of the life cycle studied, mainly schistosomulum, adult worm and egg. Additionally, we used a rabbit anti-Sm14 polyclonal antibody in an indirect immunofluorescence assay to localize Sm14 in adult worm sections. The basal lamella of the tegument and the gut epithelium were strongly labeled. These tissues have a high flow of and demand for lipids, a finding that supports the putative role of Sm14 as an intracellular transporter of fatty acids from host cells.

  9. Induction of protective immunity against Schistosoma mansoni infection by antigens purified from PIII, a fraction of adult worm, associated to the downregulation of granuloma formation

    Directory of Open Access Journals (Sweden)

    Gustavson Shauma

    1998-01-01

    Full Text Available This study was performed in order to define Schistosoma mansoni antigens able to function as modulator agents in BALB/c mice granulomatous hypersensitivity to parasite egg. The antigens P-24, P-35 and P-97 were purified by affinity chromatography from a fraction of S. mansoni adult worm antigenic preparation, denominated PIII, involved in the inhibition of granulomatous response to eggs. Immunization of mice with these antigens, in the presence of Corynebacterium parvum and Al(OH3 as adjuvant, induced a significant protection degree against challenge infection, as observed by the decrease on worm burden recovered from portal system. In vitro blastogenesis assays revealed that purified antigens were able to induce significant proliferation of spleen cells from S. mansoni-infected mice. This protection was correlated to significant decrease in granuloma size induced by PIII. From these results, we concluded that PIII preparation contains antigens capable of mediating protective anti-parasite immunity and down-regulating granulomatous hypersensitivity to S. mansoni eggs.

  10. Intersite variations of a battery of biomarkers at different levels of biological organisation in the estuarine endobenthic worm Nereis diversicolor (Polychaeta, Nereididae).

    Science.gov (United States)

    Fossi Tankoua, O; Buffet, P E; Amiard, J C; Amiard-Triquet, C; Méléder, V; Gillet, P; Mouneyrac, C; Berthet, B

    2012-06-15

    The ragworm Nereis diversicolor has been proposed as a sentinel species for the assessment of estuarine sediment quality. The aim of this study was to test the responsiveness of the worms using a battery of biomarkers in specimens from a moderately contaminated site (Loire estuary, Fr.) and a comparatively cleaner site (Bay of Bourgneuf, Fr.) as a reference site. Ragworms were collected on 7 occasions from April 2008 to October 2009 for the determination of biochemical (GST, AChE, digestive enzymes), physiological (energy reserves (glycogen, lipids and proteins), relationship between length and weight), and behavioural (feeding and burrowing) biomarkers. The biomarker responses were tentatively interpreted in terms of the concept of cascading events potentially responsible for local depletion/extinction of populations submitted to chemical stress. Impairments of AChE and amylase activities, feeding rate, energy reserve concentrations (glycogen and lipids), and the relationship between length and weight showed up differences between the reference site and the Loire estuary despite the latter being far from the most contaminated estuary in France or internationally. However, no links could be established in the Loire estuary ragworms between effects at infra-individual and individual levels, nor with worm population density, even though a small oil spill had occurred in the Loire estuary only one month before the beginning of sampling. PMID:22417766

  11. Trophic transfer of trace metals from the polychaete worm Nereis diversicolor to the polychaete N. virens and the decapod crustacean Palaemonetes varians

    Science.gov (United States)

    Rainbow, P.S.; Poirier, L.; Smith, B.D.; Brix, K.V.; Luoma, S.N.

    2006-01-01

    Diet is an important exposure route for the uptake of trace metals by aquatic invertebrates, with trace metal trophic transfer depending on 2 stages - assimilation and subsequent accumulation by the predator. This study investigated the trophic transfer of trace metals from the sediment-dwelling polychaete worm Nereis diversicolor from metal-rich estuarine sediments in southwestern UK to 2 predators - another polychaete N. virens (Cu, Zn, Pb, Cd, Fe) and the decapod crustacean Palaemonetes varians (Cu, Zn, Pb, Cd, Fe, Ag, As, Mn). N. virens showed net accumulation of Cu, Zn, Pb and Cd from the prey; accumulation increased with increasing prey concentration, but a coefficient of trophic transfer decreased with increasing prey concentration, probably because a higher proportion of accumulated metal in the prey is bound in less trophically available (insoluble) detoxified forms. The trace metal accumulation patterns of P. varians apparently restricted significant net accumulation of metals from the diet of N. diversicolor to just Cd. There was significant mortality of the decapods fed on the diets of metal-rich worms. Metal-rich invertebrates that have accumulated metals from the rich historical store in the sediments of particular SW England estuaries can potentially pass these metals along food chains, with accumulation and total food chain transfer depending on the metal assimilation efficiencies and accumulation patterns of the animal at each trophic level. This trophic transfer may be significant enough to have ecotoxicological effects. ?? Inter-Research 2006.

  12. PAS-1, a protein affinity purified from Ascaris suum worms, maintains the ability to modulate the immune response to a bystander antigen.

    Science.gov (United States)

    Oshiro, Telma M; Enobe, Cristina S; Araújo, Cláudia A; Macedo, Mahasti S; Macedo-Soares, Maria Fernanda

    2006-04-01

    Helminth infections and parasite components have potent immunomodulatory effects on a host's immune system. In the present study, we investigated the effect of PAS-1, a protein component of Ascaris suum adult worms recognized by a monoclonal antibody (MAIP-1), on humoral and cell-mediated responses to a bystander antigen (ovalbumin [OVA]). MAIP-1 recognized only one of the three polypeptide chains of PAS-1, but neutralized the suppressive effect of the whole worm extract on OVA-specific antibody production. PAS-1 inhibited antibody production against a T-cell-dependent, but not a T-cell-independent, antigen in a dose-dependent way. IgM, IgG1, IgG2b, and also IgE and anaphylactic IgG1 levels were downregulated. In addition, PAS-1 inhibited OVA-specific delayed type hypersensitivity reactions in the footpad of mice, showing a potent immunosuppressive activity on both Th1 and Th2 responses that seems to be mediated by the induction of large amounts of IL-10 and IL-4. Indeed, PAS-1-specific spleen cells secreted sevenfold more IL-10 and threefold more IL-4 than OVA-specific cells in response to in vitro restimulation with the respective antigens. In conclusion, we showed that PAS-1, a single protein component from A. suum, maintains all its immunosuppressive properties. PMID:16519731

  13. Effect of gamma rays on nucleic acids content (RNA and DNA) of the cotton leaf worm Spodoptera Littoralis (BOISD). Vol. 4

    International Nuclear Information System (INIS)

    Full grown pupae of the cotton leaf worm Spodoptera Littoralis (Boisd) were exposed to exposed to sub sterilizing doses of 100, 200 and 300 Gy gamma radiation. The changes in nucleic acids content (RNA and DNA) of irradiated pupae, after 24 hours from irradiation, and also in 3 days old adults resulting from irradiated pupae were investigated. The total nucleic acids content in either pupae or adults was progressively reduced as the dose was increased. The reduction of both RNA and DNA in females was greater than in males. DNA was more radiosensitive than RNA. The destructive action of irradiation on nucleic acids was more pronounced in adult stage. Irradiation increased the RNA/DNA ratio than control at all treatments for female pupae at 200 Gy. 2 tabs

  14. Progress on the artificial rearing of the army worm, Spodoptera (Laphygma) exigua Hb. and radiation sterilization in the male of this species

    International Nuclear Information System (INIS)

    The army worm, Spodoptera exigua Hb. was reared for 6 more generations in an artificial medium containing Mung bean as a major component. By improving the rearing temperature and humidity conditions, better rearing results were obtained. The average percentage of development from eggs to pupae, from eggs to adults, and from pupae to adults was 41.7+-4.93, 38.44+-6.32 and 88.1+-1.48 respectively. The pupal weight was also calculated. In sterilization studies, the 3-day-old male pupae were subjected to gamma rays at 0, 5 and 10 krads. Upon emerging into adults, they were mated with non-irradiated female moths. Male moths emerged from pupae subjected to 10 krads of gamma rays could significantly induce infertility in eggs deposited

  15. Design of Luffing Mechanism Based on Worm-drive%基于蜗轮蜗杆传动的俯仰机构设计

    Institute of Scientific and Technical Information of China (English)

    唐娟; 周迪锋

    2014-01-01

    介绍了俯仰机构功能及工作原理,设计了一种应用于水下机器人的俯仰机构。该俯仰机构采用蜗轮蜗杆传动,具有自锁功能,可在水下环境中带动水下机器人相关探测识别设备上仰或下俯,实现垂直工作范围的调节。%The working principle and functions of luffing mechanism are introduced ,and a luffing mechanism used in underwater ro-bot is designed .This mechanism adopts worm-drive with self-locking feature .In the underwater environment ,the detection and rec-ognition device of the underwater robot could be driven up or down to regulate its vertical work scope with the help of the luffing mechanism .

  16. Effects of uranium-contaminated sediments on the bioturbation activity of Chironomus riparius larvae (Insecta, Diptera) and Tubifex tubifex worms (Annelida, Tubificidae).

    Science.gov (United States)

    Lagauzère, S; Boyer, P; Stora, G; Bonzom, J-M

    2009-07-01

    Freshwater sediments represent a compartment for accumulation of toxic substances, notably of metallic pollutants such as uranium. However, they also constitute a privileged habitat for many benthic macro-invertebrate species with important roles in the functioning of these ecosystems, particularly through their bioturbation activities. Uranium accumulation in sediments can thus have harmful effects on these organisms (e.g., developmental delay, malformations, mortality). The present study aimed to evaluate the consequences of these effects on the bioturbation activity of Chironomus riparius larvae and Tubifex tubifex worms. These two species, which are widespread in freshwater ecosystems, are characteristic of two different modes of bioturbation: bioirrigation and upward bioconveying, respectively. By quantifying the burial and redistribution of fluorescent particulate tracers (microspheres), sediment reworking induced by these macro-invertebrates was measured after 12d of exposure. Biodiffusion D(b) and bioadvection W rates, as well as several other parameters, were estimated to assess and compare the bioturbation activity of the two species, separately and in combination, between uncontaminated and uranium-spiked sediments. The results reveal that C. riparius larvae were more sensitive to uranium, but their bioturbation activity, even under uncontaminated conditions, had little effect on sediment reworking. Particle mixing was mainly induced by T. tubifex worms, which were only affected by uranium at high concentrations in the sediment. Finally, bioturbation by T. tubifex led to a high degree of uranium release from sediment to the overlying water, which highlights the crucial role of this mostly dominant species on uranium biogeochemical cycles at concentrations existing in naturally contaminated sites. PMID:19403158

  17. 浙南猪冠尾线虫病及人患蚴移行症的发现%A study of epidemiology & pathogenesis of swine kidney worm disease and discovery of larva migrans in human beings in South Z hejiang

    Institute of Scientific and Technical Information of China (English)

    黄文德; 余大文; 汤子慧; 张峰山

    2001-01-01

    Objective:To study epidemiology of swine kidney disease(Se phanuriasis) in South Zhejiang and its harmful and disease-producing effect of lar vae of Swine Kidney worms on human beings so as to provide basis for the prevent ion and treatment of the disease.Methods:Examining the eggs swine kidney worms in the urine and worms distribution and pathological conditions; Seperating larvae from the Pige ry and infecting Guinea pigs with infective Larvae. Via mouth or skin; Obseving curative effect of the worm-killing drugs; examining Susceptible Persons and pa tients with dermatitis.Results:Infective rate of kidney worms in femal-Pigs is 50.1%; and 14.12% in flesh-Pigs. Adult worms mainly harbour around the ureter(66.67%) . The disease involves many viscera and the condition is Severe. There are a lo t of larvae of kidney worms(Sephanurus dentatus=S.d.) in the Pigery. Those clean ing th e Pigery bare footed are likely to be infected, resalting in dermatitis or ra shes. T wo larvae of .S.d. were doscovered from the migrant eruption node of the Petient .Conclusion:The Sephanuriasis was distributed. widely in the Sou th-Z hejiang and severely harmed to pigs. Larvae migrans of .S.d. in human was first di scovered. Synthetic prophylax and treatment of Sephanuriasis were employed and d esired effects were achiveved.%目的:了解浙南猪冠尾线虫病流行情况和危害 及其蚴对人的致病性。方法:检测猪尿中肾虫卵及肾虫分布处的病态,从猪舍分离感染性蚴,并经 口、肤感染豚鼠,观察杀虫药疗效。同时以免疫学检测易感人群与皮炎患者。 结果:母猪冠尾线虫感染率为50.1%,肉猪为14.1%,成虫寄生于输尿管周围 占66.7%,猪的多处脏器有病变。猪舍内冠尾线虫蚴较多,清理猪舍者易遭蚴侵袭致皮炎 ,从匐行疹处获蚴。结论:浙南猪冠尾线虫病流行广,危害性大;发现人患该蚴移行症。

  18. Efficacy of some plant oils alone and/or combined with different insecticides on the cotton leaf-worm Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) in Egypt.

    Science.gov (United States)

    Mesbah, H A; Mourad, A K; Rokaia, A Z M

    2006-01-01

    The present work was conducted to evaluate the efficiency of two essential oils ((Flax or "Linseed" and Sesame ), five volatile plant oils ( Camphor, Red basil, Rose, Menthol and Clove ), four pesticides (Methoxyfenozide; Permethrin; Profenofos and Spinosad) and their mixtures on the cotton leaf-worm Spodoptera littoralis (Boisd.). This study was also devoted to minimize the usage of conventional insecticides, reduce the environmental pollution, and protect human-beings and domestic animals from hazards due to pesticides applications. In the meantime, the delayed effect of these tested plant oils on the developing immatures and moths of the cotton leaf-worm, Spodoptera littoralis was determined. Most of the evaluated plant oils were found to have an insecticidal effect on the 4th instar larvae of the cotton leaf-worm, S. littoralis. Both the essential Sesame oil and Clove volatile oil showed rather weak toxic effect corresponding to the same concentrations and periods of the bioassay tests. Comparing the toxicity of the tested plant oils, it was affirmed that both Rose and Red basil volatile oils were the highest efficient natural phytocompounds against the treated larvae and alternatively ranked either the 1st and/or the 2nd rank, throughout the different periods of the bioassay tests, followed by the other three tested oils which were more or less efficient phytocompounds. According to the toxicity index, all the tested oils were less toxic than the superior Red basil volatile oil after 48 h. post treatment followed by the gradual decrease in toxicity of Rose, Flax and Menthol, respectively. The development of the treated 4th larval instar was blocked due to treatment with the tested plant oils. With no exception, all the efficiently tested essential and/or volatile oils acted principally as Insect Growth Inhibitors (IGIs) rather than antifeedants causing disruption of the insect development, abnormal larvae, pupae and adults that were lead finally to death. The

  19. Schistosoma mansoni: the sex ratios of worms in animals infected with cercariae from three species of Biomphalaria Schistosoma mansoni: relação de vermes machos e fêmeas em animais inoculados com cercárias de três espécies de Biomphalaria

    OpenAIRE

    Cecília Pereira de Souza; Liana K. Jannotti-Passos; Sueleny Silva Ferreira; Iaci Belo de Figueiredo Vieira

    1996-01-01

    The ratios of male to female worms of Schistosoma mansoni were determined in mice infected with cercariae from LE, SJ and AL strains shed by mollusc hosts of the parasite in Brazil. The sex ratios of worms in the animals were similar with cercariae from Biomphialaria glabrata and B. tenagophila varying from 1.1:1 to 1.6:1 with LE and AL strains and 1:1.1 with SJ. In the animals infected with cercariae from B. straminea the ratio of male to female worms was similar to those obtained using cerc...

  20. 一种基于信用的综合蠕虫检测算法%A Credit-Based Comprehensive Worm Detection Algorithm

    Institute of Scientific and Technical Information of China (English)

    杨宏宇; 米耘锋

    2013-01-01

    This paper presents a new comprehensive worm detection algorithm based on credit. Firstly, the parameters of connection success probability are optimized and set through detection contrast experiments. Secondly, the response strategy of the credit-based connection rate limiting algorithm is redesigned, and consequently the event response process of the algorithm is improved. On the basis of the above study, the new credit-based comprehensive worm detection (CBCWD) algorithm is designed to monitor network traffics, execute response strategy for monitoring events, and give the detection results through attack condition judge and comprehensive analysis. Five different frequencies attacks detection experiments on the NUST 2011 open dataset were conducted. The experiment results demonstrate that proposed algorithm has a higher detection rate and lower false positive rate.%提出一种基于信用的综合蠕虫检测算法(CBCWD)。首先,通过检测对比实验对连接成功概率参数进行优化设定;其次,在对基于信用的连接率限制算法响应策略进行了重新设计,以此为基础对该算法的响应处理过程进行了改进。在上述研究基础上,设计一种基于信用的综合蠕虫检测算法。该算法通过监测网络流量信息,对监测事件执行响应策略,通过攻击条件判定和综合分析得出检测结果。采用NUST 2011开放数据集进行5种不同频率的攻击检测对比实验,实验结果表明该算法具有更高的检测率和更低的误报率。

  1. Recall of intestinal helminthiasis by HIV-infected South Africans and avoidance of possible misinterpretation of egg excretion in worm/HIV co-infection analyses

    Directory of Open Access Journals (Sweden)

    van der Merwe Lize

    2006-05-01

    Full Text Available Abstract Background Ascariasis and HIV/AIDS are often co-endemic under conditions of poverty in South Africa; and discordant immune responses to the respective infections could theoretically be affecting the epidemic of HIV/AIDS in various ways. It is well-known that sensitisation to helminthic antigens can aggravate or ameliorate several non-helminthic diseases and impair immunisation against cholera, tetanus and tuberculosis. The human genotype can influence immune responses to Ascaris strongly. With these factors in mind, we have started to document the extent of long-term exposure to Ascaris and other helminths in a community where HIV/AIDS is highly prevalent. In more advanced studies, objectives are to analyse relevant immunological variables (e.g. cytokine activity and immunoglobulin levels. We postulate that when Ascaris is hyperendemic, analysis of possible consequences of co-infection by HIV cannot be based primarily on excretion vs non-excretion of eggs. Methods Recall of worms seen in faeces was documented in relation to the age of adult volunteers who were either seropositive (n = 170 or seronegative (n = 65 for HIV. Reasons for HIV testing, deworming treatments used or not used, date and place of birth, and duration of residence in Cape Town, were recorded. Confidence intervals were calculated both for group percentages and the inter-group differences, and were used to make statistical comparisons. Results In both groups, more than 70% of participants were aware of having passed worms, often both when a child and as an adult. Most of the descriptions fitted Ascaris. Evidence for significantly prolonged exposure to helminthic infection in HIV-positives was supported by more recall of deworming treatment in this group (p Conclusion There was a long-term history of ascariasis (and probably other helminthic infections in both of the groups that were studied. In women in the same community, and in children living where housing and

  2. SM1.3 Seismic Centers Data Acquisition: an introduction to Antelope, EarthWorm, SeisComP and their usage around the world

    Science.gov (United States)

    Pesaresi, Damiano; Sleeman, Reinoud

    2010-05-01

    Many medium to big size seismic data centers around the world are facing the same question: which software to use to acquire seismic data in real-time? A home-made or a commercial one? Both choices have pros and cons. The in-house development of software usually requires an increased investment in human resources rather than a financial investment. However, the advantage of fully accomplishing your own needs could be put in danger when the software engineer quits the job! Commercial software offers the advantage of being maintained, but it may require both a considerable financial investment and training. The main seismic software data acquisition suites available nowadays are the public domain SeisComP and EarthWorm packages and the commercial package Antelope. Nanometrics, Guralp and RefTek also provide seismic data acquisition software, but they are mainly intended for single station/network acquisition. Antelope is a software package for real-time acquisition and processing of seismic network data, with its roots in the academic seismological community. The software is developed by Boulder Real Time Technology (BRTT) and commercialized by Kinemetrics. It is used by IRIS affiliates for off-line data processing and it is the main acquisition tool for the USArray program and data centers in Europe like the ORFEUS Data Center, OGS (Italy), ZAMG (Austria), ARSO (Slovenia) and GFU (Czech Republic). SeisComP was originally developed for the GEOFON global network to provide a system for data acquisition, data exchange (SeedLink protocol) and automatic processing. It has evolved into to a widely distributed, networked seismographic system for data acquisition and real-time data exchange over Internet and is supported by ORFEUS as the standard seismic data acquisition tool in Europe. SeisComP3 is the next generation of the software and was developed for the German Indonesian Tsunami Early Warning System (GITEWS). SeisComP is licensed by GFZ (free of charge) and

  3. 疟原虫和蠕虫混合感染免疫相关机制的研究进展%Progress in Immune Related Mechanism by Mixed Infection of Plasmodium and Worms

    Institute of Scientific and Technical Information of China (English)

    王美莲; 罗恩杰

    2012-01-01

    疟疾是一类由疟原虫引起的寄生虫传染病,疟原虫与蠕虫混合感染现象在热带和亚热带等疟痰流行区普遍存在,是当前寄生虫免疫研究领域内的热点之一.本文就疟原虫与蠕虫混合感染的研究现状及相关免疫机制作一综述.%Malaria is one of parasite infectious diseases caused by the plasmodium. Mixed infections of plasmodium and worms universally exist in tropical and subtropical malaria-prevalent areas, and are one of hot research fields in parasitology and immunology. A review on current study and related immune mechanism of mixed infection by plasmodium and worms were summarized in this paper.

  4. Propagation Model of Email Worm-virus Based on Heterogeneous Networks%基于异质网络的邮件蠕虫病毒传播模型

    Institute of Scientific and Technical Information of China (English)

    项春霞; 蒋国平; 夏玲玲; 宋波

    2016-01-01

    文中根据现实生活中邮件蠕虫病毒发生后个体不同的行为机制,以及安装杀毒软件的概率和杀毒软件的查杀能力随时间变化的事实,结合邮件网络的结构特性,提出了一种改进的基于异质网络的邮件蠕虫病毒 SEIR(Susceptible-Ex-posed-Infected-Removed)传播模型。结合邮件蠕虫病毒的传播特点,利用相互作用的马尔可夫链方法推导出相应的 SEIR模型的动力学方程组,表征邮件蠕虫病毒的传播过程。通过蒙特卡罗方法对 SEIR 模型传播动力学过程进行实验仿真,探索影响邮件蠕虫病毒传播的基本因素。仿真结果表明,改进的邮件蠕虫病毒 SEIR 传播模型更加符合真实邮件网络上的蠕虫病毒传播过程,且快速地提高杀毒软件的安装概率以及杀毒软件的查杀能力能够有效地抑制邮件蠕虫病毒的传播。%Currently,email has become one of the most commonly communication in daily life,while email worm-virus constitutes one of the major Internet security threats and has attracted considerable attention. Therefore,the research on the spreading models of email worm-virus has a great significance in preventing and controlling the propagation of email viruses. The probability of installing antivirus soft-ware,and the virus-killing ability of antivirus software are time-varying when the email worm-virus outbreaks. According to the above factors and the different opening probability of suspicious email caused by individual differences,propose an improved email worm-virus spreading SEIR (Susceptible-Exposed-Infected-Removed) model in heterogeneous networks with consideration of the scale-free fea-ture of email networks. Use the Interaction of Markov Chains (IMC) method to derive the dynamical equations of SEIR model,represen-ting the process of email worm-virus propagation. Furthermore,Monte-Carlo method is used to explore the basic factors affecting the propagation of email worm

  5. Climatic influences on development and survival of free-living stages of equine strongyles: implications for worm control strategies and managing anthelmintic resistance.

    Science.gov (United States)

    Nielsen, Martin K; Kaplan, Ray M; Thamsborg, Stig M; Monrad, Jesper; Olsen, Susanne N

    2007-07-01

    Development of resistance to anthelmintic drugs by horse strongyles constitutes a growing threat to equine health because it is unknown when new drug classes can be expected on the market. Consequently, parasite control strategies should attempt to maintain drug efficacy for as long as possible. The proportion of a parasite population that is not exposed to anthelmintic treatment is described as being "in refugia" and although many factors affect the rate at which resistance develops, levels of refugia are considered the most important as these parasites are not selected by treatment and so provide a pool of sensitive genes in the population. Accordingly, treatment should be avoided when pasture refugia are small because such treatments will place significant selection pressure for resistance on worm populations. Given this new paradigm for parasite control, it has become important to identify seasons and circumstances wherein refugia are diminished. Free-living stages of equine strongyles are highly dependent on climatic influences, and this review summarises studies of strongyle development and survival under laboratory and field conditions in Northern (cool) temperate, Southern (warm) temperate and subtropical/tropical climates. In Northern temperate climates, refugia are smallest during the winter. In contrast, refugia are lowest during the summer in warm temperate and subtropical/tropical climates. Although adverse seasonal changes clearly have significant effects on the ability of free living stages of strongyle nematode parasites to survive and develop, available data suggest that climatic influences cannot effectively "clean" pastures from one grazing season to the next. PMID:16815051

  6. Biological response of the cotton leaf worm, Spodoptera littoralis, towards combination of seed and leaf extracts from red gum Eucalyptus Camaldulensis and/or gamma radiation

    International Nuclear Information System (INIS)

    The biological response of the F1 progeny of the cotton leaf worm, Spodoptera Littoralis (Bosid.), (from males irradiated as parental pupae with 75 and 125 Gy gamma radiation) to seed or leaf extracts of Eucalyptus Camaldulensis plant were studied. The fecundity, fertility, and mating potency of F1 adults were employed as assess for response. Analysis of variance indicated that, different treatments with gamma irradiation and/or plant extracts, at most mating crosses and most interactions between all of them, showed significant role in decreasing the fecundity and fertility of F1 adults. In general, the combined treatments of seed or leaf extracts with gamma irradiation. as dependent factors regardless other factors, decreased the emergence of adults compared to the control or single treatments of either seed extract or gamma irradiation. As well, combination treatments of radiation and seed extract decreased significantly the fecundity of moths compared to control or irradiation treatment alone. On the other hand, the combination treatments of either seed or leaf extracts did not have any significant difference in the number of mating per female, as compared to control, while irradiation treatments decreased the number of mating compared to vontrol. The effects of most possible probabilities of interaction between doses, crosses and treatments on reproduction were estimated and discussed and also the effects on development of F1 progeny were included

  7. A comparative study of size-controlled worm-like amylopectin nanoparticles and spherical amylose nanoparticles: Their characteristics and the adsorption properties of polyphenols.

    Science.gov (United States)

    Qiu, Chao; Qin, Yang; Zhang, Shuangling; Xiong, Liu; Sun, Qingjie

    2016-12-15

    Polyphenols are known to have potent antioxidant capacity and other health-beneficial bioactivities. However, extremely low absorption rate of polyphenols restricts their bioactivity in vivo. Development of biopolymer nanoparticle carrier is a promising solution. For the first time, we have successfully prepared worm-like amylopectin nanoparticles (APNPs) and spherical amylose nanoparticles (AMNPs) using fractionated amylose and amylopectin from potato starch. Additionally, adsorption kinetics and adsorption isotherms of three polyphenols (procyanidins, epicatechins and catechins) on AMNPs and APNPs were investigated. We found that procyanidins, epicatechins, and catechins could bind to AMNPs at levels of up to 1.2, 1.5, and 1.4g/g, respectively, while the APNPs demonstrated higher adsorption amounts of 1.4, 4.3, and 2.2g/g, respectively. Furthermore, the particle size of polyphenol-loaded nanoparticles was not significantly changed. The results suggested that APNPs and AMNPs can be applied as an effective nanocarrier by delivering active compounds for nutraceutical and pharmaceutical industries. PMID:27451221

  8. Iridium ultrasmall nanoparticles, worm-like chain nanowires, and porous nanodendrites: One-pot solvothermal synthesis and catalytic CO oxidation activity

    Science.gov (United States)

    Zhang, Tao; Li, Shuai-Chen; Zhu, Wei; Ke, Jun; Yu, Jing-Wen; Zhang, Zhi-Ping; Dai, Lin-Xiu; Gu, Jun; Zhang, Ya-Wen

    2016-06-01

    We report a facile one-pot solvothermal synthesis of monodisperse iridium (Ir) ultrasmall (1.5-2.5 nm in diameter) nanoparticles (NPs), worm-like chain nanowires (NWs), and porous nanodendrites (NDs), for which CO oxidation reaction has been employed as a probe reaction to investigate the effects of nanoparticle size and surface-capping organics on the catalytic activities. Time-dependent experiments revealed that an oriented attachment mechanism induced by the strong adsorption of halide anions (Br- and I-) on specific facet of Ir nanoclusters or by decreasing the reduction rate of Ir precursors with changing their concentrations during the synthesis was responsible for the formation of Ir NWs and NDs. Annealing tests indicated that an O2-H2 atmosphere treatment turned out to be an effective measure to clean up the surface-capping organics of Ir NPs supported on commercial SiO2. Catalytic CO oxidation reaction illustrated that a significant improvement in the catalytic activity of CO oxidation reaction was achieved together with the changing of activation energies after such atmosphere treatment for the supported catalysts of the ultrasmall Ir NPs. It is noteworthy that this enhancement in catalytic activity could be ascribed to the changes in the surface status (including populations of Ir species in metallic and oxidized states, removal of surface capping organics, the variety of active sites, and total effective active site number) for the supported nanocatalysts during the atmosphere treatment.

  9. The multi-hemoglobin system of the hydrothermal vent tube worm Riftia pachyptila. I. Reexamination of the number and masses of its constituents.

    Science.gov (United States)

    Zal, F; Lallier, F H; Wall, J S; Vinogradov, S N; Toulmond, A

    1996-04-12

    The deep-sea tube worm Riftia pachyptila Jones possesses a well developed circulatory system and a large coelomic compartment, both containing extracellular hemoglobins. Fresh vascular blood is heterogeneous and contains two different hemoglobins (V1 and V2), whereas the coelomic fluid is homogeneous and comprises only one hemoglobin (C1). Their molecular weights have been determined by scanning transmission electron microscopy mass mapping (STEM) and by multi-angle laser light scattering (MALLS). Both methods yielded approximately the same molecular weights with masses significantly higher than the literature data for V1. V1, V2, and C1 had Mr of 3396 +/- 540 x 10(3), 393 +/- 71 x 10(3), and 410 +/- 51 x 10(3) by STEM, and 3503 +/- 13 x 10(3), 433 +/- 8 x 10(3), and 380 +/- 4 x 10(3) by MALLS, respectively. Transmission electron micrographs of V1 are typical of an hexagonal bilayer hemoglobin (HBL Hb). When submitted to dilution or osmotic shock, V1 dissociates into halves and one-twelfth subunits like annelid HBL Hbs. V1 is resistant to urea treatment, indicating that hydrophobic interactions play a small role in its quaternary structure. Conversely, V1 Hb is rather unstable in solution without denaturant, a property which seems to be characteristic of vestimentiferan HBL Hbs and could be explained by an important number of hydrogen bonds. PMID:8621528

  10. Enzyme-linked immunosorbent assay with worm vomit and cercarial secretions of Schistosoma mansoni to detect infections in an endemic focus of Burkina Faso.

    Science.gov (United States)

    Bahgat, M; Sorgho, H; Ouédraogo, J B; Poda, J N; Sawadogo, L; Ruppel, A

    2006-03-01

    Cercariae and adult Schistosoma mansoni were used to prepare, respectively, cercarial secretions (CS) and worm vomit (WoV). These were used as antigens in an enzyme-linked immunosorbent assay (ELISA) to test the IgG-reactivity of sera obtained in an S. mansoni-endemic area of Burkina Faso. Among the egg-excreting individuals (n = 240), 94.6% reacted positively with WoV, but only 62.9% with CS, thus suggesting a high diagnostic sensitivity of WoV, but not of CS. Among those individuals without detectable eggs in two Kato-Katz thick smears from different stool specimens (n = 215), the respective percentages of positive IgG reactivity were 78.1% and 63.3%. These positive reactions in the absence of detectable eggs are interpreted in terms of limited sensitivity of parasitological stool examinations. Optical density values in ELISA with CS, but not with WoV, correlated negatively with age, which may reflect decreasing exposure to cercariae in older individuals. PMID:16469168

  11. Random Sampling of Squamate Reptiles in Spanish Natural Reserves Reveals the Presence of Novel Adenoviruses in Lacertids (Family Lacertidae) and Worm Lizards (Amphisbaenia)

    Science.gov (United States)

    Szirovicza, Leonóra; López, Pilar; Kopena, Renáta; Benkő, Mária; Martín, José; Pénzes, Judit J.

    2016-01-01

    Here, we report the results of a large-scale PCR survey on the prevalence and diversity of adenoviruses (AdVs) in samples collected randomly from free-living reptiles. On the territories of the Guadarrama Mountains National Park in Central Spain and of the Chafarinas Islands in North Africa, cloacal swabs were taken from 318 specimens of eight native species representing five squamate reptilian families. The healthy-looking animals had been captured temporarily for physiological and ethological examinations, after which they were released. We found 22 AdV-positive samples in representatives of three species, all from Central Spain. Sequence analysis of the PCR products revealed the existence of three hitherto unknown AdVs in 11 Carpetane rock lizards (Iberolacerta cyreni), nine Iberian worm lizards (Blanus cinereus), and two Iberian green lizards (Lacerta schreiberi), respectively. Phylogeny inference showed every novel putative virus to be a member of the genus Atadenovirus. This is the very first description of the occurrence of AdVs in amphisbaenian and lacertid hosts. Unlike all squamate atadenoviruses examined previously, two of the novel putative AdVs had A+T rich DNA, a feature generally deemed to mirror previous host switch events. Our results shed new light on the diversity and evolution of atadenoviruses. PMID:27399970

  12. Histological studies of gamma irradiation and/ or bacillus thuringiensis var. berliner on the testes and ovaries of the black cut worm, Agitators Ipsilon (HUFN.)

    International Nuclear Information System (INIS)

    The present study was carried out to determine the effects of the sub sterilizing dose of gamma radiation (100 Gy) applied to the full grown pupae as well as two concentrations (50 and 100 ppm) of Bacillus thuringiensis var Berliner (Crycl A) applied to the fourth instar larvae and their combination on the histology of the testis and overies of the adults (male or female) black cut worm, Agrotis ipsilon (Hufn.), throughout the first filial (F1) generation. The results indicated that the testes showed many symptoms of retardation in their growth in the form of retardation of spermatogenesis, reduction in sperm bundle numbers, degeneration and liquefaction of sperm bundles which lead to appearance of large vacuoles or retardation in sperm maturation. The data also showed that the follicular epithelial cells in the ovarioles (F, female ovary) appeared abnormal in shape, beside their limited separation from the developing oocytes, which became shrinking, semi absorbed or completely absorbed leaving vacuoles. Otherwise, the oocyte shape became rectangular and the nurse cells were reduced in size or absent in some parts

  13. Efficacy of an enzyme-linked immunosorbent assay as a diagnostic tool for schistosomiasis mansoni in individuals with low worm burden

    Directory of Open Access Journals (Sweden)

    Edward José de Oliveira

    2005-07-01

    Full Text Available IgM-ELISA is an immunoenzymatic method useful for detection of IgM antibodies against a fraction of Schistosoma mansoni adult worm antigen (AWA that is soluble in trichloroacetic acid (AWA-TCA. This method was applied to three groups of individuals with different clinical and epidemiological characteristics, and the results compared with those obtained by other diagnostic methods: immunofluorescence test for detection of IgM antibodies (IgM-IFT or IgG antibodies (IgG-IFT, ELISA for detection of IgG antibodies (IgG-ELISA, and two parasitological methods, Kato-Katz and miracidium hatching. The IgM-ELISA presented a sensitivity of 98%, when the parasitologic fecal examination was defined as reference diagnostic method, and a specificity of 98 and 97.3%, respectively for the group of clinically healthy individuals and other helminth carriers. A comparative analysis between the results of IgM-ELISA and those obtained by other serologic tests showed a good degree of agreement, with Kappa indices ranging from 0.95 to 0.98. The diagnostic efficacy of 97.8%, as determined with schistosomiasis patients with low parasitic burden, suggests the excellent performance of the IgM-ELISA and its usefulness for the diagnosis of schistosomiasis when applied in low endemic areas.

  14. Immunization with PIII, a fraction of Schistosoma mansoni soluble adult worm antigenic preparation, affects nitric oxide production by murine spleen cells

    Directory of Open Access Journals (Sweden)

    Diana Magalhães de Oliveira

    1998-01-01

    Full Text Available Nitric oxide (NO is an important effector molecule involved in immune regulation and defense. NO produced by cytokine-activated macrophages was reported to be cytotoxic against the helminth Schistosoma mansoni. Identification and characterization of S. mansoni antigens that can provide protective immunity is crucial for understanding the complex immunoregulatory events that modulate the immune response in schistosomiasis. It is, then, essential to have available defined, purified parasite antigens. Previous work by our laboratory identified a fraction of S. mansoni soluble adult worm antigenic preparation (SWAP, named PIII, able to elicit significant in vitro cell proliferation and at the same time lower in vitro and in vivo granuloma formation when compared either to SEA (soluble egg antigen or to SWAP. In the present work we report the effect of different in vivo trials with mice on their spleen cells ability to produce NO. We demonstrate that PIII-immunization is able to significantly increase NO production by spleen cells after in vitro stimulation with LPS. These data suggest a possible role for NO on the protective immunity induced by PIII.

  15. Biological and physiological studies on the effect of some botanical oils and gamma irradiation on the Greasy Cut Worm Agrotis Ipsilon (HUF)

    International Nuclear Information System (INIS)

    The greasy cut worm, Agrotis ipsilon ( Lepidoptera-Noctuidae ) is a serious pest for the seedlings of most crops such as cotton, maize, beans, broccoli, cabbage, carrot, chinese broccoli, chinese cabbage, Chinese spinach, corn, eggplant, flowering white cabbage, green beans, head cabbage, lettuce, mustard cabbage, potato, spinach, sugarcane, sweet potato, tomato, turnip, as well as many other plants. An extensive listing of hosts of the greasy cutworm may be found in (Rings et al. 1975). The extensive and continuous use of synthetic pesticides in control of agricultural pests have created many problems, one of them is the incapability of toxic agents in controlling the target pests at the recommended doses. Therefore, it was of great interest to investigate some alternative methods as substitutes for insecticides in the control of this pest. Among these methods, is the irradiation, plant extracts and oils. Irradiation techniques seem to offer solutions that are desirable in many aspects, contributing that this treatment should eventually prove to be cheaper, safer and more reliable than chemical control. Irradiation shortens life span of insects (Baxter and Blair, 1969), possibly by accelerating senescence (Aly et al., 1996). Irradiation may also cause protein denaturation, which may impair enzyme activity (Ljubenov and Andreev, 1974) and (Tribe and Webb, 1979 a, b, c). According to (Kinipling, 1955), insect exposure to ionizing radiation causes sterilization through induction of dominates lethal mutation in the genetic structure of organisms. This technique to be successful control device for suppressing and combating many lepidopteraus insect pests, including Agrotis ipsilon has been studied

  16. Citation patterns of a controversial and high-impact paper: Worm et al. (2006 "Impacts of biodiversity loss on ocean ecosystem services".

    Directory of Open Access Journals (Sweden)

    Trevor A Branch

    Full Text Available Citation patterns were examined for Worm et al. 2006 (Science 314:787-790, a high-impact paper that focused on relationships between marine biodiversity and ecosystem services. This paper sparked much controversy through its projection, highlighted in the press release, that all marine fisheries would be collapsed by 2048. Analysis of 664 citing papers revealed that only a small percentage (11% referred to the 2048 projection, while 39% referred to fisheries collapse in general, and 40% to biodiversity and ecosystem services. The 2048 projection was mentioned more often in papers published soon after the original paper, in low-impact journals, and in journals outside of fields that would be expected to focus on biodiversity. Citing papers also mentioned the 2048 projection more often if they had few authors (28% of single-author papers vs. 2% of papers with 10 or more authors. These factors suggest that the more knowledgeable the authors of citing papers were about the controversy over the 2048 projection, the less likely they were to refer to it. A noteworthy finding was that if the original authors were also involved in the citing papers, they rarely (1 of 55 papers, 2% mentioned the 2048 projection. Thus the original authors have emphasized the broader concerns about biodiversity loss, rather than the 2048 projection, as the key result of their study.

  17. Development of Software for Fine-pitch Worm Gear Tester%小模数蜗杆副综合误差测量软件的研制

    Institute of Scientific and Technical Information of China (English)

    张白; 谈伟; 潘元庆; 恽洪园

    2011-01-01

    基于单面啮合原理的小模数蜗杆副综合误差测量仪,可以测量蜗杆副切向综合误差、齿距偏差和侧隙.详细介绍了该仪器的测量流程、软件界面、软件结构、误差提取算法和精度等级评定.该软件具有参数管理、自动测量、误差计算、用户管理、SPC分析、频谱分析、等级评定、结果保存、打印报表等功能,可以应用于小模数蜗杆副的精密检测.%The fine-pitch worm gear pair tester based on single flank contant principle can measure tangential composite deviation, pitch deviation and backlash. The software structure, error extraction algorithms, deviation evaluation,measuring process and interface of the software of the tester are mainly introduced. Main functions of the software include: parameters managing, auto-measuring, deviation calculation, user management, SPC analysis, spectrum analysis, grade assessment, saving results and inspection report & print.

  18. A new look at the ventral nerve centre of Sagitta: implications for the phylogenetic position of Chaetognatha (arrow worms and the evolution of the bilaterian nervous system

    Directory of Open Access Journals (Sweden)

    Müller Carsten HG

    2007-05-01

    Full Text Available Abstract Background The Chaetognatha (arrow worms are a group of marine carnivores whose phylogenetic relationships are still vigorously debated. Molecular studies have as yet failed to come up with a stable hypothesis on their phylogenetic position. In a wide range of metazoans, the nervous system has proven to provide a wealth of characters for analysing phylogenetic relationships (neurophylogeny. Therefore, in the present study we explored the structure of the ventral nerve centre ("ventral ganglion" in Sagitta setosa with a set of histochemical and immunohistochemical markers. Results In specimens that were immunolabeled for acetylated-alpha tubulin the ventral nerve centre appeared to be a condensed continuation of the peripheral intraepidermal nerve plexus. Yet, synapsin immunolocalization showed that the ventral nerve centre is organized into a highly ordered array of ca. 80 serially arranged microcompartments. Immunohistochemistry against RFamide revealed a set of serially arranged individually identifiable neurons in the ventral nerve centre that we charted in detail. Conclusion The new information on the structure of the chaetognath nervous system is compared to previous descriptions of the ventral nerve centre which are critically evaluated. Our findings are discussed with regard to the debate on nervous system organisation in the last common bilaterian ancestor and with regard to the phylogenetic affinities of this Chaetognatha. We suggest to place the Chaetognatha within the Protostomia and argue against hypotheses which propose a deuterostome affinity of Chaetognatha or a sister-group relationship to all other Bilateria.

  19. Mechanism of fluorescence and conformational changes of the sarcoplasmic calcium binding protein of the sand worm Nereis diversicolor upon Ca2+ or Mg2+ binding.

    Science.gov (United States)

    Sillen, Alain; Verheyden, Stefan; Delfosse, Lotte; Braem, Tania; Robben, Johan; Volckaert, Guido; Engelborghs, Yves

    2003-09-01

    The calcium-binding protein isolated from the sarcoplasm of the muscles of the sand worm Nereis diversicolor has four EF-hands and three active binding sites for Ca(2+) or Mg(2+). Nereis diversicolor sarcoplasmic calcium-binding protein contains three tryptophan residues at positions 4, 57, and 170, respectively. The Wt protein shows a very limited fluorescence increase upon binding of Ca(2+) or Mg(2+). Single-tryptophan-containing mutants were produced and purified. The fluorescence titrations of these mutants show a limited decrease of the affinity for calcium, but no alterations of the cooperativity. Upon adding calcium, Trp170 shows a strong fluorescence increase, Trp57 an extensive fluorescence decrease, and Trp4 shows no fluorescence change. Therefore mutant W4F/W170F is ideally suited to analyze the fluorescence titrations and to study the binding mechanism. Mutations of the calcium ligands at the z-position in the three binding sites show no effect at site I and a total loss of cooperativity at sites III and IV. The quenching of Trp57 upon calcium binding is dependent on the presence of arginine R25, but this residue is not just a simple dynamic quencher. The role of the salt bridge R25-D58 is also investigated. PMID:12944301

  20. Cold seep biogenic carbonate crust in the Levantine basin is inhabited by burrowing Phascolosoma aff. turnerae, a sipunculan worm hosting a distinctive microbiota

    Science.gov (United States)

    Rubin-Blum, Maxim; Shemesh, Eli; Goodman-Tchernov, Beverly; Coleman, Dwight F.; Ben-Avraham, Zvi; Tchernov, Dan

    2014-08-01

    Biogenic calcium carbonate crusts represent a cryptic habitat that is often associated with hydrocarbon seeps. Most biological observations of these crusts concern the external surfaces and the fauna inhabiting their inner cavities are generally neglected. Exposed carbonates in areas of active seepage at the 1100-m-deep base of the Palmachim slumping feature in the Levantine basin are intensively burrowed by metazoans, especially by sipunculans (peanut worms), identified by genetic and morphological markers as a potentially novel Phascolosoma sp., closely related to Phascolosoma turnerae (Rice, 1985) and named here P. aff. turnerae. Bacterial 16S-based tag encoded FLX amplicon pyrosequencing (bTEFAP) was utilized to analyze the bacterial community associated with P. aff. turnerae. We compared the bacterial community structure in P. aff. turnerae to the bacterial community structure associated with the sediment-water interface in adjacent gas seeps and in biofilm covering the carbonate crust hosting the sipunculan. A distinctive microbiota, capable of chemosynthesis and sulfide detoxification, was found in association with P. aff. turnerae.

  1. A shore-based preliminary survey of marine ribbon worms (Nemertea from the Caribbean coast of Colombia

    Directory of Open Access Journals (Sweden)

    Jaime Gonzalez

    2014-09-01

    Full Text Available A checklist of benthic ribbon worm species from the Caribbean coast of Colombia is presented, including synonyms, distributions, a photographic record, and the main morphologic characters of each species for a rapid identification. This is the first research focused broadly on nemerteans in Colombia. 54 specimens of nemerteans were hand-collected from the rocky littoral of two different localities, and identified according to personal experience and specialist literature. 13 species were found; of which 11 represent new records for the country. These species belong to eight different traditionally used families: Tubulanidae, Valenciniidae, Lineidae, Amphiporidae, Cratenemertidae, Emplectonematidae, Drepanophoridae and Ototyphlonemertidae. The most common and abundant species was Dushia atra. The biodiversity of nemerteans in Colombia seems to overlap with the nemertean fauna from Florida and Brazil, explained by the convergence of the North Brazil Current, Guiana Current, Caribbean Currents and the Panama-Colombia Contracurrent in the sampled region. The results of this work suggest that the Caribbean coast of Colombia is a region with a high diversity of nemerteans, and provide important taxonomic data for environmental assessments and future biological research.

  2. A new look at the ventral nerve centre of Sagitta: implications for the phylogenetic position of Chaetognatha (arrow worms) and the evolution of the bilaterian nervous system

    OpenAIRE

    Müller Carsten HG; Harzsch Steffen

    2007-01-01

    Abstract Background The Chaetognatha (arrow worms) are a group of marine carnivores whose phylogenetic relationships are still vigorously debated. Molecular studies have as yet failed to come up with a stable hypothesis on their phylogenetic position. In a wide range of metazoans, the nervous system has proven to provide a wealth of characters for analysing phylogenetic relationships (neurophylogeny). Therefore, in the present study we explored the structure of the ventral nerve centre ("vent...

  3. Marcadores de riesgo para individuos con altas cargas de Ascaris lumbricoidesen una comunidad rural del Estado Cojedes, Venezuela Risk markers for the high worm burden condition for Ascaris lumbricoides in a rural community of Venezuela

    Directory of Open Access Journals (Sweden)

    Gustavo Morales

    1999-07-01

    Full Text Available A total of 337 individuals from a rural community of Venezuela (Mapurite, Estado Cojedes were studied. Stoll faecal examination was carried out and the total number of A. lumbricoides was recovered after the treatment of the individuals sampled with Pyrantel pamoate at a dose of 10 mg/Kg body weight in children and 15 mg/Kg in adults. A relationship between the high worm burden condition (individuals excreting more than10000 epg of A. lumbricoides and the age of the hosts was found. Resulting with the major values of relative risk index (Rr the 5-9 years old class (Rr= 3.2 t= 3.4. This relationship was not found between high worm burden condition (HWB and the sex of the hosts. The following individuals have the the highest possibilities to become HWB: with blood group A (Rr=3.05 t= 4.08, with haemoglobine type HbA HbS (Rr=1.86 t= 2.13, individuals with the combinations A HbA HbF (Rr= 3.46 t= 2.31 and A HbA HbS (Rr= 3.11 t= 2.78. It was estimated that the selective treatment of the total HWB detected (72 with an effective product, determined a reduction of 95.4% of the environmental contamination with de eggs and 72.3% of the worm burden

  4. 双包络蜗轮蜗杆的现代设计与检测方法(邀请论文)%Computerized Design and Measurement of Double-enveloping Worm-Gears ( Invited Paper)

    Institute of Scientific and Technical Information of China (English)

    陈宁新

    2015-01-01

    Centered on the two typical models of double-enveloping worm-gear drives in current gear industry, i. e. , orthogonal and non-orthogonal axes of worm and machine table for generating worm thread surfaces, a powerful computer program that can design and analyze the above two different models was developed. The program includes all state of the art technology, such as undercutting and contact boundary lines for both worm thread and gear tooth surface cuttings, relative curvatures, instant contact lines and contact stripes, meshing angles, relative sliding, tooth contact analysis ( TCA ) , CMM measurement, single and double contact areas and their contact ratios, etc. The modern gear design method was illustrated by two numerical examples to design and analyze two different double-enveloping worm-gear drives.%针对目前齿轮工业中存在的2种不同类型双包络蜗轮蜗杆,即加工时蜗杆轴线与机床转台轴线正交型和不正交型,为研发双包络蜗轮蜗杆,将这2种不同的类型统一在一个计算机程序中,包含了现代齿轮设计中根切线与接触线包络界线、相对曲率、瞬时接触线与接触带、啮合角、相对滑动、齿面接触分析( tooth contact analysis, TCA)、齿面测量、单-双线接触区及其重合系数分析等最新技术,以及蜗杆螺旋齿面在三坐标测量机( coordinate measuring machine, CMM)上的测量方法,通过2个算例设计分析了2种不同双包络蜗轮蜗杆,展示了齿轮设计的现代方法.

  5. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - MILWAUKEE WORM DRIVE CIRCULAR SAW OENHP{number_sign}: 2001-02, VERSION A

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2002-01-05

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Milwaukee worm drive circular saw was assessed on August 14, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Milwaukee worm drive circular saw is a hand-held tool with a 7 1/4-inch diameter circular blade for cutting wood. The saw contains a fixed upper and a retractable lower blade guard to prevent access to the blade during use. The unit is operated with an on/off guarded trigger switch; and is supported with a handgrip mounted on top of the saw. An adjustable lever sets the depth of cut. The retractable blade guard permits blind or plunge cuts and protects from blade access during shutdown and blade coast. Kickback, the sudden reaction to a pinched blade, is possible when using this saw and could cause the saw to lift up and out of the work piece toward the operator. Proper work position and firm control of the saw minimizes the potential for a sprain or strain. Care needs to be exercised to support the work piece properly and to not force the tool. Personal noise sampling indicated that one worker was near the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) while the other was at the Action Level with time-weighted averages (TWA's) of 82.7 and 84.6 dBA, respectively. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it

  6. The New World screw-worm as a pest in the Caribbean and plans for its eradication from Jamaica and the other infested Caribbean islands

    International Nuclear Information System (INIS)

    The screw-worm, Cochliomyia hominivorax Coquerel (NWS), was eradicated from the Caribbean island of Curacao in 1964 (Baumhover et al. 1955). This programme was considered as a test of the SIT principle. In 1959, the pest was eradicated from Florida with the concept fully established as a sound and novel entomological principle (Baumhover 1966). In 1962, a similar programme was initiated in the southeastern United States with a barrier established along the Mexican-US Border (Bushland 1975). In 1975, the pest was eradicated from the island of Puerto Rico, the US and the British Virgin Islands (Williams et al. 1977). In 1981, the pest was totally eradicated from the United States and in 1986 from all of Mexico. It has since been eradicated from Belize, Guatemala, Honduras, El Salvador and Nicaragua. The eventual goal of the programme is to eradicate the pest from Costa Rica and Panama down to the Derail Gap where a sterile fly barrier will be maintained. In the Caribbean, an estimated 86% of the land mass is considered infested by the New World screw-worm. Jamaica, Hispaniola, Cuba, Trinidad and Tobago are the countries known to be infested. Despite this fact, no comprehensive plans have ever been made for its eradication from these countries which together have a total livestock population of well over 16 million (Table 1). However, based on the great success of the programme elsewhere and recent interest shown by various international organisations and governments in countries which are infested, the situation is changing rapidly. Currently, the country which is most prepared for an eradication programme is Jamaica where government officials have long shown an interest in eradicating the pest. For example, in 1959, a group of Jamaican livestock owners visited officials associated with the Florida eradication programme. Since this date, serious consideration has been given and several attempts made by Jamaica to implement an eradication programme but without success

  7. Toxicity of some insecticides to F1 progeny of the cotton leaf worm; Spodoptera littoralis (Boisd) gamma irradiated as parental pupae (Lepidoptera: Noctuidae)

    International Nuclear Information System (INIS)

    The response of the F1 Progeny of Cotton Leaf worm; Spodoptera littoralis Boisd, (from male irradiated as parental pupae with 0, 50, 100 and 150 Gy of gamma irradiation) to Silicron, Atabron and Catabroun were studied. The lethal concentration doses of insecticides that kill 10,50 and 90 % of population (LC10, LC50 and LC90); The lethal time that kill 50% of population (LT50) and the Tolerance Ratio(T.R) to the different previous insecticides were employed as parameters for measuring the response of irradiated and un-irradiated progeny. The results indicated that, the dose of irradiation and time post insecticides application had a great role in alter the response of F1 progeny of S. littoralis to the different-insecticides. Also, gamma irradiation increased the toxicity of Silicron at 2 and 4 days post insecticide treatments. By time elapsing after insecticide application the irradiated larvae became virtually the same degree of susceptibility as compared to non-irradiated ones. As well, 50 Gy slightly alter the toxicity of Atabron, while population irradiated with 100 and 150 Gy showed a high level of susceptibility to Atabron at 22 and 26 days post insecticide treatments as compared to un-irradiated population. In addition, the toxicity of Catabroun increased in case of irradiated population at most of interval time post insecticide treatments as compared to un-irradiated ones. Furthermore, a Comparison was made and discussed between the susceptibility of irradiated population only, population treated with insecticides only and population treated with both insecticides and radiation by using the standard parameter LT50

  8. Prevalence and risk factors associated with worm infestation in pre-school children (6-23 months in selected blocks of Uttar Pradesh and Jharkhand, India

    Directory of Open Access Journals (Sweden)

    Awasthi S

    2008-12-01

    Full Text Available Background :Intestinal worm infestation is widely prevalent in developing countries and can result in impaired nutrition and development. Aims: To estimate prevalence of and risk factors for intestinal geohelminths and other intestinal parasites in children aged 6 to 23 months. Settings and Design: Cross sectional study in rural India. Materials and Methods: Proportionate population size sampling method was used to randomly select 15 villages per block. Thereafter, house-to-house survey was done to recruit eligible children and obtain fecal sample for microbiological examination. Statistical Analysis: Univariate distribution of variables was assessed and comparison between categorical variables and continuous variables was done using a Chi-square test and student′s t-test, respectively. Odds ratio was calculated to assess associations. Results: Overall 926 children were recruited and 909 fecal samples examined. Combined prevalence of infestation with intestinal geohelminths treatable by albendazole and other intestinal parasites non-treatable by albendazole was 50.3% (457/909 and 51.6% (469/909, respectively. Exclusive use of hand pump water (OR = 1.79, CI = 1.36-2.35, P < 0.001 and use of hand pump water plus field defecation increased risk of geohelminthic infection (OR = 1.75 CI = 1.34-2.30, P < 0.001 while use of well water (OR = 0.45 CI= 0.33-0.60, P < 0.001 and exclusive use of soap and water practice for hand washing after defecation was protective (OR = 0.54, CI = 0.40-0.73, P < 0.001. Conclusion: Since almost half the children are infected with intestinal geohelminths treatable by albendazole, targeted deworming of population in this age group should be considered.

  9. The seeds and the worms

    DEFF Research Database (Denmark)

    Brorson, Stig

    2006-01-01

    The Polish microbiologist and philosopher of science, Ludwik Fleck (1896-1961), was a pioneer in constructivist history and philosophy of science. Based on studies in the history of syphilis, Fleck hypothesized that many established scientific facts are linked, in their development, to pre-scient...

  10. The rainbow and the worm

    OpenAIRE

    Hunt, Tam

    2013-01-01

    What is life? Many have asked this question, and no definitive answer is yet widely accepted. Is life something truly distinct from non-living stuff, as many dualists have suggested for millennia? Is there an élan vital that distinguishes living from dead stuff? Or is life about certain types of organization, metabolism, reproduction, goal-oriented behavior? None of these answers have yet won the debate. There is, however, an intriguing new set of ideas that have been developed by Mae-Wan Ho,...

  11. The multi-hemoglobin system of the hydrothermal vent tube worm Riftia pachyptila. II. Complete polypeptide chain composition investigated by maximum entropy analysis of mass spectra.

    Science.gov (United States)

    Zal, F; Lallier, F H; Green, B N; Vinogradov, S N; Toulmond, A

    1996-04-12

    The deep-sea tube worm Riftia pachyptila Jones possesses a complex of three extracellular Hbs: two in the vascular compartment, V1 (approximately 3500 kDa) and V2 (approximately 400 kDa), and one in the coelomic cavity, C1 (approximately 400 kDa). These native Hbs, their dissociation products and derivatives were subjected to electrospray ionization mass spectrometry (ESI-MS). The data were analyzed by the maximum entropy deconvolution system. We identified three groups of peaks for V1 Hb, at approximately 16, 23 27, and 30 kDa, corresponding to (i) two monomeric globin chains, b (Mr 16,133.5) and c (Mr 16,805.9); (ii) four linker subunits, L1 L4 (Mr 23,505.2, 23,851.4, 26,342.4, and 27,425.8, respectively); and (iii) one disulfide-bonded dimer D1 (Mr 31,720.7) composed of globin chains d (Mr 15,578.5) and e (Mr 16, 148.3). V2 and C1 Hbs had no linkers and contained a glycosylated monomeric globin chain, a (Mr 15,933.4) and a second dimer D2 (Mr 32,511.7) composed of chains e and f (Mr 16,368.1). The dimer D1 was absent from C1 Hb, clearly differentiating V2 and C1 Hbs. These Hbs were also subjected to SDS-PAGE analysis for comparative purposes. The following models are proposed ((cD1)(bD1)3) for the one-twelfth protomer of V1 Hb, ((cD)(bD)6(aD)) (D corresponding to either D1 or D2) for V2 and C1 Hbs. HBL V1 Hb would be composed of 180 polypeptide chains with 144 globin chains and 36 linker chains, each twelfth being in contact with three linker subunits, providing a total molecular mass = 3285 kDa. V2 and C1 would be composed of 24 globin chains providing a total molecular mass = 403 kDa and 406 kDa, respectively. These results are in excellent agreement with experimental Mr determined by STEM mass mapping and MALLS. PMID:8621529

  12. Inherited sterility in the cotton leaf worm Spodoptera littoralis,(Boisd.), and changes in the DNA pattern as a result of using gamma radiation

    International Nuclear Information System (INIS)

    The present study was conducted to evaluate the effect of gamma irradiation on certain biological aspects of the cotton leaf worm Spodoptera littoralis (Boisd.). Laboratory experiments were carried out to investigate the effect of the sub sterilizing doses of 0, 50, 150, 250, 350 and 450 Gy of gamma irradiation (cobalt and cesium sources) on different generations of Spodoptera littoralis irradiated as pupae to study the inherited sterility. A dose level at 450 Gy completely inhibited full pupal development, but the emerged adult at the dose 350 Gy did not lay eggs, whether they were combined with non-irradiated or irradiated individuals of opposite sexes. The produced adults (P) showed increasing sterility with increasing the irradiation dose. While, their fertility, fecundity, pupation percent and adult emergence were found to be reduced in the parents followed by F1, but increased in F2. In all cases, sex ratio was shifted in favor of males. A significant negative relationship between dose levels and percentage of egg hatching was obtained; [the higher the dose, the lower the percentage of egg hatching]. The percentage of egg hatching resulting from irradiated male pupae was higher than that resulting from irradiated female pupae. Females were more sensitive for irradiation than males. Cobalt irradiation source was more effective than cesium source. The effect of gamma irradiation on the DNA pattern of adult male parents, F1 and F2 showed alterations among the controls, the treated parents, F1 and F2 individuals. Exposure to irradiation caused very frequently the appearance of some extra bands and the deficiency of others in the RAPD- PCR and ISSR amplification pattern of the irradiated insects. The appearance of extra bands was attributed to the repair mechanism that occur in the irradiation damaged DNA. However, the similarity in DNA patterns between some normal and treated samples was interpreted by assuming that the irradiation induced damage was in regions

  13. Study on the use of sheep serum post vaccination of three phase larva (L3) Haemonchus contortus worm irradiated inoculated to rabbit

    International Nuclear Information System (INIS)

    Study has been done on rabbit to find out the effect of giving sheep serum post vaccination with irradiated gastric worm challenged with infective H. contortus larva. Forty eight local rabbit divided into 3 groups : K, VI and V2, each groups: consists of 4 rabbit, by using 4 times repetition. K group which only inoculated 10,000L3 H. contortus infective. V1 = group which twice serum inoculated with 21 days interval, inoculation dose were 0,3 ml serum each, and challenged with 10.000 L3 H.contortus infective. V2 = group which 3 times serum inoculation with 21 days interval, inoculation dose 0,3 ml serum each and challenged with 10.000 L3 H.contortus infective. Design model used with Completely Random Design (RAL), Duncan was used as inter treatment test. Parameter observed are total protein fraction, Larva L4 content in gaster, cumulative weight gain, and death percentage rabbits. Result of study showed that on average parameter total protein fraction on K + 2,0086 ± 0,2353 mg/dl, V1 = 3,2781 ± 0,9227 mg/dl and V2 = 5,5035 ± 1,6794 mg/d. Average parameter L4 death showed on K = 10, V1 = 8, and V2 = 4, while L4 alive on K = 3, V1 + 1 and V2 = 0. Commutative Average parameter PCV value on K = 19,91 ± 1,24%, V1= 27,31 ± 1,22%, and V2 35,71 ± 0,56 %. Average parameter weight gain per week on K = 24,46 ± 0,74 g, V1 = 26,04 ± 2.23 g, and V2 = 28,93 ± 1,67 g. Percentage average parameter death rate on K = 37,5 ± 14,46%, V1=18,75 ± 23,90% and V2 = 0± 0%. The conclusion of the study result was serum inoculation on rabbits have positive result on reducing anaemia rate, elevating weight gain, reduce death percentage, reduced L4 alive content in gaster, and able oneelevate immunity respond content that is total protein fraction on rabbits. (author)

  14. Acquiring data in real time in Italy from the Antarctic Seismographic Argentinean Italian Network (ASAIN): testing the global capabilities of the EarthWorm and Antelope software suites.

    Science.gov (United States)

    Percy Plasencia Linares, Milton; Russi, Marino; Pesaresi, Damiano; Cravos, Claudio

    2010-05-01

    The Italian National Institute for Oceanography and Experimental Geophysics (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, OGS) is running the Antarctic Seismographic Argentinean Italian Network (ASAIN), made of 7 seismic stations located in the Scotia Sea region in Antarctica and in Tierra del Fuego - Argentina: data from these stations are transferred in real time to the OGS headquarters in Trieste (Italy) via satellite links provided by the Instituto Antártico Argentino (IAA). Data is collected and archived primarily in Güralp Compress Format (GCF) through the Scream! software at OGS and IAA, and transmitted also in real time to the Observatories and Research Facilities for European Seismology (ORFEUS). The main real time seismic data acquisition and processing system of the ASAIN network is based on the EarthWorm 7.3 (Open Source) software suite installed on a Linux server at the OGS headquarters in Trieste. It runs several software modules for data collection, data archiving, data publication on dedicated web servers: wave_serverV, Winston Wave Server, and data analysis and realtime monitoring through Swarm program. OGS is also running, in close cooperation with the Friuli-Venezia Giulia Civil Defense, the North East (NI) Italy seismic network, making use of the Antelope commercial software suite from BRTT as the main acquisition system. As a test to check the global capabilities of the Antelope software suite, we also set up an instance of Antelope acquiring data in real time from both the regional ASAIN seismic network in Antarctica and a subset of the Global Seismic Network (GSN) funded by the Incorporated Research Institution for Seismology (IRIS). The facilities of the IRIS Data Management System, and specifically the IRIS Data Management Center, were used for real time access to waveform required in this study. The first tests indicated that more than 80% of the earthquakes with magnitude M>5.0 listed in the Preliminary Determination

  15. Curiouser and Curiouser: The Macrocyclic Lactone, Abamectin, Is also a Potent Inhibitor of Pyrantel/Tribendimidine Nicotinic Acetylcholine Receptors of Gastro-Intestinal Worms.

    Science.gov (United States)

    Abongwa, Melanie; Buxton, Samuel K; Robertson, Alan P; Martin, Richard J

    2016-01-01

    Nematode parasites may be controlled with drugs, but their regular application has given rise to concerns about the development of resistance. Drug combinations may be more effective than single drugs and delay the onset of resistance. A combination of the nicotinic antagonist, derquantel, and the macrocyclic lactone, abamectin, has been found to have synergistic anthelmintic effects against gastro-intestinal nematode parasites. We have observed in previous contraction and electrophysiological experiments that derquantel is a potent selective antagonist of nematode parasite muscle nicotinic receptors; and that abamectin is an inhibitor of the same nicotinic receptors. To explore these inhibitory effects further, we expressed muscle nicotinic receptors of the nodular worm, Oesophagostomum dentatum (Ode-UNC-29:Ode-UNC-63:Ode-UNC-38), in Xenopus oocytes under voltage-clamp and tested effects of abamectin on pyrantel and acetylcholine responses. The receptors were antagonized by 0.03 μM abamectin in a non-competitive manner (reduced Rmax, no change in EC50). This antagonism increased when abamectin was increased to 0.1 μM. However, when we increased the concentration of abamectin further to 0.3 μM, 1 μM or 10 μM, we found that the antagonism decreased and was less than with 0.1 μM abamectin. The bi-phasic effects of abamectin suggest that abamectin acts at two allosteric sites: one high affinity negative allosteric (NAM) site causing antagonism, and another lower affinity positive allosteric (PAM) site causing a reduction in antagonism. We also tested the effects of 0.1 μM derquantel alone and in combination with 0.3 μM abamectin. We found that derquantel on these receptors, like abamectin, acted as a non-competitive antagonist, and that the combination of derquantel and abamectin produced greater inhibition. These observations confirm the antagonistic effects of abamectin on nematode nicotinic receptors in addition to GluCl effects, and illustrate more complex

  16. Curiouser and Curiouser: The Macrocyclic Lactone, Abamectin, Is also a Potent Inhibitor of Pyrantel/Tribendimidine Nicotinic Acetylcholine Receptors of Gastro-Intestinal Worms.

    Directory of Open Access Journals (Sweden)

    Melanie Abongwa

    Full Text Available Nematode parasites may be controlled with drugs, but their regular application has given rise to concerns about the development of resistance. Drug combinations may be more effective than single drugs and delay the onset of resistance. A combination of the nicotinic antagonist, derquantel, and the macrocyclic lactone, abamectin, has been found to have synergistic anthelmintic effects against gastro-intestinal nematode parasites. We have observed in previous contraction and electrophysiological experiments that derquantel is a potent selective antagonist of nematode parasite muscle nicotinic receptors; and that abamectin is an inhibitor of the same nicotinic receptors. To explore these inhibitory effects further, we expressed muscle nicotinic receptors of the nodular worm, Oesophagostomum dentatum (Ode-UNC-29:Ode-UNC-63:Ode-UNC-38, in Xenopus oocytes under voltage-clamp and tested effects of abamectin on pyrantel and acetylcholine responses. The receptors were antagonized by 0.03 μM abamectin in a non-competitive manner (reduced Rmax, no change in EC50. This antagonism increased when abamectin was increased to 0.1 μM. However, when we increased the concentration of abamectin further to 0.3 μM, 1 μM or 10 μM, we found that the antagonism decreased and was less than with 0.1 μM abamectin. The bi-phasic effects of abamectin suggest that abamectin acts at two allosteric sites: one high affinity negative allosteric (NAM site causing antagonism, and another lower affinity positive allosteric (PAM site causing a reduction in antagonism. We also tested the effects of 0.1 μM derquantel alone and in combination with 0.3 μM abamectin. We found that derquantel on these receptors, like abamectin, acted as a non-competitive antagonist, and that the combination of derquantel and abamectin produced greater inhibition. These observations confirm the antagonistic effects of abamectin on nematode nicotinic receptors in addition to GluCl effects, and

  17. Utilización de Sistemas Basados en Reglas y en Casos para diseñar transmisiones por tornillo sinfín // Use of rules based systems and cases based systems for worm gear design

    Directory of Open Access Journals (Sweden)

    Jorge Laureano Moya‐Rodríguez

    2012-01-01

    Full Text Available Las técnicas de Inteligencia Artificial se aplican hoy en día a diferentes problemas de Ingeniería,especialmente los Sistemas Basados en el Conocimiento. Entre estos últimos los más comunes son losSistemas Basados en Patrones, los Sistemas Basados en Reglas, los Sistemas Basados en Casos y losSistemas Híbridos. Los Sistemas Basados en Casos parten de problemas resueltos en un dominio deaplicación y mediante un proceso de adaptación, encuentran la solución a un nuevo problema. Estossistemas pueden ser usados con éxito para el diseño de engranajes, particularmente para el diseño detransmisiones por tornillo sin fin, sin embargo ello constituye un campo de las aplicaciones de laInteligencia Artificial aún inexplorada. En el presente trabajo se hace una comparación del uso de losSistemas Basados en Regla y los Sistemas Basados en Casos para el diseño de transmisiones portornillo sin fin y se muestran los resultados de la aplicación de los sistemas basados en regla al diseñoparticular de una transmisión por tornillo sin fin.Palabras claves: tornillo sin fin, engranajes, sistemas basados en casos, sistemas basados en reglas,inteligencia artificial.____________________________________________________________________________AbstractNowadays Artificial Intelligence techniques are applied successfully to different engineering problems,especially the “Knowledge Based Systems”. Among them the most common are the “Frame basedSystems”, “Rules Based Systems”, “Case Based Systems” and "Hybrid Systems". The “Case BasedSystems” (CBS analyze solved problems in an application domain and by means of a process ofadaptation; they find the solution to a new problem. These systems can be used successfully for thedesign of gears, particularly for designing worm gears; nevertheless it constitutes a field of the applicationsof artificial intelligence even unexplored. A comparison of the use of “Rules Based System” and

  18. 蛔虫提取物对小鼠Lewis肺癌细胞的细胞毒性作用%Cytotoxic action of a whole worm extract of Ascaris lumbricoides on LLC

    Institute of Scientific and Technical Information of China (English)

    杨小军; 彭卫东; 徐友妹; 袁铿

    2011-01-01

    目的 探讨蛔虫提取物对小鼠Lewis肺癌细胞(LLC)的细胞毒作用. 方法 选用8种浓度的蛔虫提取物诱导小鼠Lewis肺癌细胞.分别在诱导后24、48、72 h采用四氮唑盐酶还原法(MTT)测A492值,计算细胞存活率和抑制率.结果 不同浓度的蛔虫提取物分别作用LLC细胞24、48和72 h,对LLC细胞的增殖均有明显的抑制作用,呈剂量依赖.且以48 h抑制作用最强,之后随着作用时间的延长,BEAL对肿瘤细胞的抑制作用降低. 结论 蛔虫提取物对小鼠Lewis肺癌细胞具有细胞毒性作用,能够诱导LLC细胞发生凋亡.%Objective To investigate the cytotoxic action of a whole worm extract of Ascaris lumbricoides (BEAL) on a lewis lung carcinoma cell (LLC) line in vitro.Methods Eight concentrations of whole worm extract of A.lumbricoides were chosen to induce cytotoxicity in LLC.Twenty-four, 48, and 72 h after induction, the cell survival rate and inhibition rate were calculated according to the A492 results of a microculture tetrazolium test (MTT).Results Twenty-four, 48, and 72 h after induction with different concentrations of whole worm extract of A.lumbricoides, the inhibition rate behaved in a concentration-dependent manner.The inhibition rate peaked 48 h after induction but decreased afterwards.Conclusion A whole worm extract of A.lumbricoides had varying levels of cytotoxicity on LLC and induced cell apoptosis.

  19. Procedimiento para evaluar el grado de precisión de elaboración del engranaje de tornillo sinfín. // Procedure to evaluate the degree of accuracy of elaboration of the worm gear.

    Directory of Open Access Journals (Sweden)

    G. Rivero Llerena

    2008-05-01

    Full Text Available Esta investigación brinda un procedimiento que permite evaluar el grado de precisión del engranaje de tornillo sinfíncilíndrico con perfil Zk, considerando la geometría externa e interna y los errores de fabricación e instalación propiosde la tecnología de elaboración. Se utiliza un procedimiento teórico que, combinado con las mediciones físicas de lahuella de contacto, da lugar a un método basado en el empleo de nomogramas que contienen los parámetros delcontacto entre los flancos activos del engranaje.Palabras clave: Tornillo sinfín, geometría, precisión, huella, contacto._______________________________________________________________________________Summary.This investigation offers a procedure that allows to evaluate the degree of accuracy of the cylindrical worm gear withprofile Zk, whereas clause the external and internal geometry and the manufacturing errors and installation characteristic ofthe elaboration technology. A theoretical procedure is used that, cocktail wit the physical mensurations of the contact print,gives place to a method based on the nomograms employment that you/they contain the parameters of the contact amongthe active flanks of the engagement.Password: worm gear, geometry, precision, print, contact.

  20. A light-responsive organofluid based on reverse worm-like micelles formed from an equi-charged, mixed, anionic gemini surfactant with an azobenzene spacer and a cationic conventional surfactant.

    Science.gov (United States)

    Yang, Duoping; Zhao, Jianxi

    2016-05-01

    An equally-charged mixture of an anionic gemini surfactant, O,O'-bis(sodium 2-tetradecylcarboxylate)-p-azodiphendiol (G14-azo), and a cationic surfactant, cetyltrimethylammonium bromide (CTAB), was dissolved in cyclohexane to form reverse worm-like micelles. Samples with different surfactant concentrations and amounts of added water were studied using rheological measurements. The amount of water, represented as the molar ratio of water to total surfactants W0, was c. 13 (at its minimum) in these equally charged systems of G14-azo (200 mmol L(-1))/CTAB. The low shear viscosity ηL of this system reached 4370 Pa s at W0 = 13 and the dynamic rheological result showed typical surfactant gel behaviour. Under UV-light irradiation, the transparent sample (G14-azo (300 mmol L(-1))/CTAB (600 mmol L(-1))) at W0 = 40 became turbid, during which ηL was rapidly reduced from the original 285 Pa s to 0.3 Pa s, indicating a transition of aggregate morphology from reverse worms into simple reverse micelles. Then the sample was returned to its original homogeneous state with c. 290 Pa s viscosity under visible light irradiation. However, this transition cannot be well achieved at low W0 due to the interior cores being too small. This limit has been attributed to both the Gemini type of surfactant molecule and to the inverted structure of aggregates. PMID:27021435