KNOWLEDGE MANAGEMENT IN CUBAN ENTERPRISES

Directory of Open Access Journals (Sweden)

Raúl Yoel La Fé Jiménez

2017-10-01

Full Text Available In Cuba the intensive use of knowledge has focused on some sectors more than others, despite the high level of training of human resources and the need to boost the Cuban economy with efficiency. This is the reason why the objective of this article is to propose a procedure for the implementation and improvement of knowledge management in Cuban companies. For this purpose, it was created a series of phases that follows a logical sequence for the implementation and improvement of knowledge management in any type of company.

Management of nuclear information and knowledge in Cuban institutions

International Nuclear Information System (INIS)

Garcia, A.G.; Rondon, C.F.; Aldama, C.L.; Aruca, L.A.; Labrada, C.

2004-01-01

In the framework of the management of information and the knowledge, the Cuban Agency of Nuclear Energy and Advanced Technologies recognizes as needful the establishment of the nuclear knowledge management system. In the rank of the Nuclear Ramal Program are executed projects, with the participation of all the Cuban nuclear institutions, focused to develop the web site and the intranet of the proper agency as support to the process of taking decisions, to develop the networking education system for human resources of these institutions and others that belong to the energy sector in Cuba, to introduce the data warehousing process for all institutions on corporate levels, to develop technology watching system for all the scientific and technical activities linked to the use and application of the peaceful use of nuclear energy, based on the information and knowledge contained in the databases of INIS, WIPO and RRIAN, between other purposes. (author)

The Cuban National Healthcare System: Characterization of primary healthcare services.

Directory of Open Access Journals (Sweden)

Keli Regina DAL PRÁ

2015-10-01

Full Text Available This article presents a report on the experience of healthcare professionals in Florianópolis, who took the course La Atención Primaria de Salud y la Medicina Familiar en Cuba [Primary Healthcare and Family Medicine in Cuba], in 2014. The purpose of the study is to characterize the healthcare units and services provided by the Cuban National Healthcare System (SNS and to reflect on this experience/immersion, particularly on Cuba’s Primary Healthcare Service. The results found that in comparison with Brazil’s Single Healthcare System (SUS Cuba’s SNS Family Healthcare (SF service is the central organizing element of the Primary Healthcare Service. The number of SF teams per inhabitant is different than in Brazil; the programs given priority in the APS are similar to those in Brazil and the intersectorial nature and scope of the services prove to be effective in the resolution of healthcare problems.

[The beginning of the Cuban demographic revolution].

Science.gov (United States)

Hernandez Castellon, R

1981-01-01

The characteristics of the Cuban demographic revolution associated with the main economic, political, and social changes in the country are analyzed. The authors begin with a brief historical outline of the political-economic situation in the country in the middle of the 19th century. There is emphasis on the dependency of the Cuban economy and its monoproducer nature (with sugar being the major export). This was due to the Spanish colonization and to the subsequent American neocolonization. The discovery of the cause for yellow fever by a Cuban physician and the sanitation campaign conducted by the Americans contributed to a diminishing of mortality. A great migratory flow occurred due to the price of sugar in the world market. This must have influenced Cuban demographic patterns which are a major factor linked to the demographic revolution. The influence on proliferation of urbanization and educational trends is emphasized. The low participation in economic activities of women during the early part of the century did affect fertility levels. The trends in mortality throughout the period 1907-43 are pointed out. It was found that 1 major aspect which had a bearing on Cuban demographic patterns was the 2 large migratory flows. An analysis of growth rates in the population--which also confirms the demographic changes in Cuba--is presented. It is concluded that the 4th decade of this century witnessed Cuba's entry in a new stage of the demographic revolution, a stage in which decreased fertility and mortality go together to create a new period. (author's)

Where is the Cuban economy heading ?

OpenAIRE

Herrera , Rémy

2006-01-01

URL des Cahiers : http://mse.univ-paris1.fr/MSEFramCahier2006.htm; Cahiers de la Maison des Sciences Economiques 2006.32 - ISSN 1624-0340; This article is the introduction of an issue (to be published) of the U.S. review International Journal of Political Economy on the Cuban economy, and coordinated by Rémy Herrera. It deals with the progresses, but also with the deficiencies, of the Cuban revolution in the economic field, until the recent de-dollarization. It underlines its economic challen...

Osteopilus septentrionalis (Cuban treefrog)

Science.gov (United States)

Glorioso, Brad M.; Steece, Aaron; Lemann, Zachary K.; Lazare, Remy; Beck, James W.

2016-01-01

USA: LOUISIANA: St. Tammany Parish: on private property on Allen Road in Slidell (ca. 30.262°N, 89.741°W; WGS 84). 2 April 2013. Aaron Steece. Verified by Hardin Waddle. Florida Museum of Natural History (UF 177727, photo voucher). New parish record. This adult was found ca. 2 m high on a branch at the edge of a wooded area behind a house. It was photographed and released, as the species identity and significance was unknown. The origin of this individual is unknown. The homeowner stated that he bought nursery plants often, but checked them thoroughly as he put them indoors. Since this initial finding, the homeowner learned more about Cuban Treefrogs and searched for them on many occasions at this location for two years, but detected no additional Cuban Treefrogs.

Co-occurrence of invasive Cuban Treefrogs and native treefrogs in PVC pipe refugia

Science.gov (United States)

Elston, Laura M.; Waddle, J. Hardin; Rice, Kenneth G.; Percival, H. Franklin

2013-01-01

The Cuban Treefrog (Osteopilus septentrionalis) was first introduced to Florida at Key West. Since this introduction, Cuban Treefrogs have spread to Miami and are now established throughout most of peninsular Florida. Cuban Treefrogs can become very abundant in areas they colonize. Several reasons contribute to their success, including a generalist diet, high fecundity and the ability to reproduce year-round, and use of disturbed or human-modified habitats. Scientists and managers are concerned that Cuban Treefrogs may contribute to the decline of native treefrogs. Cuban Treefrogs may exclude native treefrogs through both competition and predation. Because the evidence from our study and others suggests that Green and Squirrel Treefrogs do not alter their behavior to avoid Cuban Treefrogs, there is cause for concern that sampling with PVC pipes may increase the vulnerability of the native species to predation. This possibility needs further research, including whether other species of native treefrogs sympatric to where Cuban Treefrogs have invaded are also naïve to the possible threat posed by these frogs, and also if native treefrogs eventually learn to avoid Cuban Treefrogs.

Multi-elemental characterization of Cuban natural zeolites

International Nuclear Information System (INIS)

Rizo, O.D.; Peraza, E.F.H.

1997-01-01

Concentration of 38 elements in samples from four important Cuban zeolite beds have been obtained by Instrumental Neutron Activation (INAA) and X-ray Fluorescence analyses (XRFA). In comparison with other analytical techniques good agreement was reached. The concentration values of minor element Ba, Sr, Zn and Mn and 25 trace element (including 9 REE) are at the first time reported in Cuban zeolite. It is important for the zeolite evaluation in different industrial uses. (author)

Multi-elemental characterization of Cuban natural zeolites

International Nuclear Information System (INIS)

Diaz Rizo, O.; Herrera Peraza, E.F.

1996-01-01

Concentrations of 38 elements in samples from four important Cuban zeolite bed have beam obtained by Instrumental Neutron Activation (INAA) and X-Ray Fluorescence Analysis (XRFA). In comparison with other analytical techniques good agreement was achieved. The concentration values of minor element Ba, Sr, Zn, and Mn, and 25 trace element (including 9 REE) are at the first time reported in Cuban zeolite. It is important for the zeolite evaluation in different industrial uses

ring system

African Journals Online (AJOL)

1,3,2-DIAZABORACYCLOALKANE. RING SYSTEM. Negussie Retta" and Robert H. Neilson. 'Department of Chemistry, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia. Department of Chemistry, Texas Christian University.

45 CFR 401.12 - Cuban and Haitian entrant cash and medical assistance.

Science.gov (United States)

2010-10-01

... cash and medical assistance (and related administrative costs) to Cuban and Haitian entrants according... 45 Public Welfare 2 2010-10-01 2010-10-01 false Cuban and Haitian entrant cash and medical... ENTRANT PROGRAM § 401.12 Cuban and Haitian entrant cash and medical assistance. Except as may be otherwise...

Planetary ring systems properties, structures, and evolution

CERN Document Server

Murray, Carl D

2018-01-01

Planetary rings are among the most intriguing structures of our solar system and have fascinated generations of astronomers. Collating emerging knowledge in the field, this volume reviews our current understanding of ring systems with reference to the rings of Saturn, Uranus, Neptune, and more. Written by leading experts, the history of ring research and the basics of ring–particle orbits is followed by a review of the known planetary ring systems. All aspects of ring system science are described in detail, including specific dynamical processes, types of structures, thermal properties and their origins, and investigations using computer simulations and laboratory experiments. The concluding chapters discuss the prospects of future missions to planetary rings, the ways in which ring science informs and is informed by the study of other astrophysical disks, and a perspective on the field's future. Researchers of all levels will benefit from this thorough and engaging presentation.

State of malnutrition in Cuban hospitals.

Science.gov (United States)

Barreto Penié, Jesús

2005-04-01

We assessed the current state of undernutrition as observed in 1905 patients hospitalized in 12 Cuban health care institutions, as part of a Latin American, multinational survey similar in design and goals. We surveyed 1905 randomly selected patients from 12 Cuban hospitals in a two-phase study. Patients' clinical charts were audited in phase 1, the Subjective Global Assessment was used to assess patients' nutritional status in phase 2. The study was locally conducted by a properly trained team. The frequency of undernutrition in Cuban hospitals was 41.2% (95% confidence interval = 38.9 to 43.4), and 11.1% of patients were considered severely undernourished. Statistically significant (P hospital services/specialties were identified: geriatrics (56.3%), critical care (54.8%), nephrology (54.3%), internal medicine (48.6%), gastroenterology (46.5%), and cardiovascular surgery (44.8%). Malnutrition rates increased progressively with prolonged length of stay. A high malnutrition rate was observed among participating hospitals. The design and inception of policies that foster intervention programs focusing on early identification of hospital malnutrition and its timely management is suggested to decrease its deleterious effects on outcomes of health care in the participating hospitals.

Evidence for Quantisation in Planetary Ring Systems

OpenAIRE

WAYTE, RICHARD

2017-01-01

Absolute radial positions of the main features in Saturn's ring system have been calculated by adapting the quantum theory of atomic spectra. Fine rings superimposed upon broad rings are found to be covered by a harmonic series of the form N α A(r)1/2, where N and A are integers. Fourier analysis of the ring system shows that the spectral amplitude fits a response profile which is characteristic of a resonant system. Rings of Jupiter, Uranus and Neptune also obey the same rules. Involvement o...

Nostalgia, Shame and the Transplanted Cuban: "la cubana arrepentida"

Directory of Open Access Journals (Sweden)

Olga Lorenzo

2005-03-01

Full Text Available Literature can illuminate and extend our understanding of the affect of shame. In this paper, I will use extracts from my fictional works, published and in progress, and other fictional work and poetry by Cuban and Cuban-American exile writers to illustrate some aspects of shaming in relation to the experience of being a Cuban-American migrant in the United States, particularly relative to the sense of exilic nostalgia for the lost homeland. I will also look at how shame is used by the minority culture to control, erode or slow the process of assimilation and to try to maintain the illusion of the superiority of the minority culture.

Cuban Landscapes

DEFF Research Database (Denmark)

Scarpaci, Joseph L.; Portela, Armando

This accessible book offers a vivid geographic portrait of Cuba, exploring the island’s streetscapes, sugar cane fields, beaches, and rural settlements; its billboards, government buildings, and national landmarks. The authors illuminate how natural and built landscapes have shaped Cuban identity...... (cubanidad), and vice versa. They provide a unique perspective on Cuba’s distinct historical periods and political economies, from the colonial period through republicanism and today’s socialist era. Compelling topics include the legacies of slavery and the sugar industry, the past and future of urban...

Evolving Cuban-CARICOM relations : a comparative cost/benefit analysis

Directory of Open Access Journals (Sweden)

Michael Erisman

1995-01-01

Full Text Available Survey of the basic developmental dynamics involved in the evolving Cuban-CARICOM relationship. On the basis of a cost-risk/benefit analysis, the author provides some projections regarding the future of this relationship. He concludes that there appear sufficient potential benefits for both sides to deepen the relationship. Cuban-CARICOM integration, however, has no top priority for either partner.

New Main Ring control system

International Nuclear Information System (INIS)

Seino, K.; Anderson, L.; Ducar, R.; Franck, A.; Gomilar, J.; Hendricks, B.; Smedinghoff, J.

1990-03-01

The Fermilab Main Ring control system has been operational for over sixteen years. Aging and obsolescence of the equipment make the maintenance difficult. Since the advent of the Tevatron, considerable upgrades have been made to the controls of all the Fermilab accelerators except the Main Ring. Modernization of the equipment and standardization of the hardware and software have thus become inevitable. The Tevatron CAMAC serial system has been chosen as a basic foundation in order to make the Main Ring control system compatible with the rest of the accelerator complex. New hardware pieces including intelligent CAMAC modules have been designed to satisfy unique requirements. Fiber optic cable and repeaters have been installed in order to accommodate new channel requirements onto the already saturated communication medium system. 8 refs., 2 figs

The U.S. Navy and the Cuban Missile Crisis

Science.gov (United States)

1990-05-22

telephone industries . However, the CIA 10 underestimated the hatred for Batista, even among the influential Cuban middle class, although Washington...for collective defense should Castro attempt to export his revolucion . Only days later, Kennedy slapped a trade embargo on Cuba, forbidding all exchange...and bribing foreign industrial firms to sabotage their Cuban 30 exports. Far from inspiring revolt, however, these sabotage activities actually had

Lectures on algebraic system theory: Linear systems over rings

Science.gov (United States)

Kamen, E. W.

1978-01-01

The presentation centers on four classes of systems that can be treated as linear systems over a ring. These are: (1) discrete-time systems over a ring of scalars such as the integers; (2) continuous-time systems containing time delays; (3) large-scale discrete-time systems; and (4) time-varying discrete-time systems.

Requirements for a text that integrates the oncological pharmacy into the Cuban national health care system

International Nuclear Information System (INIS)

Arbesú Michelena, Ma Antonieta; Sedeño Argilagos, C. Caridad; Fernández Argüelles, Rogelio Alberto

2015-01-01

Introduction: oncological patients are cared for at all health care system levels. The pharmaceutical professional requires unifying instructions for his/her work in order to be part of the health team. Currently, there is no domestic literature for the pharmaceutical services, mainly that one devoted to oncological area, which comprises in just one text all the functional requirements and directs his/her professional daily work. Objective: to verify the requirement for national integral literature for the development of the oncological pharmaceutical service work. Methods: one two-question questionnaire was designed to assess the knowledge of experts and another with eight questions to learn about the requirement for literature on oncological pharmaceutical service adapted to the conditions of the Cuban health system. The questionnaires were e-mailed to 15 pharmacists who had an outstanding experience in several activities of the oncological pharmacy. Results: ten university experts, with 14.5 years of work experience as average in assistance activities from three provinces, responded. Two were excluded because their low level of information on oncological activity; poor incorporation of the pharmacist involved in services to activities inherent to his/her formation. All the experts believed that it was necessary to have a comprehensive text on the tasks, functions and activities linked to the oncological patient care, and to use the formal learning pathways for updating. A positive association with the favorable answers (1.40) was noticed. Conclusions: there exists a need for a text as a guide of the oncological pharmaceutical services according to the demands of the Cuban health care system. (author) 1

Researching in education findings visibility: How Cubans are doing?

Directory of Open Access Journals (Sweden)

Torres, Paúl A.

2012-07-01

Full Text Available The paper presents an analysis of Cuban educational research visibility by considering international ranking positioning of intellectual production in the field of education. A case study is conducted with outstanding Cuban educational researchers comparing their results with other prestigious professionals in the continent. Finally, new basic resources are proposed and explained for improving Bibliometric indicators by taking advantage of Google Scholar potentials in favoring international ranking positioning.

Nuclear analytical techniques in Cuban Sugar Industry

International Nuclear Information System (INIS)

Diaz Riso, O.; Griffith Martinez, J.

1996-01-01

This paper is a review concerning the applications of Nuclear Analytical Techniques in the Cuban sugar industry. The most complete elemental composition of final molasses (34 elements ) and natural zeolites (38) this last one employed as an auxiliary agent in sugar technological processes has been performed by means of Instrumental Neutron Activation Analysis (INAA) and X-Ray Fluorescence Analysis (XRFA). The trace elements sugar cane soil plant relationship and elemental composition of different types of Cuban sugar (rawr, blanco directo and refine) were also studied. As a result, valuable information referred to the possibilities of using these products in animal and human foodstuff so as in other applications are given

The nuclear issue in the cuban press. Challenges and realities

International Nuclear Information System (INIS)

Contreras Izquierdo, Marta; Rodriguez Guerra, Ingrids; Gonzalez Montoto, Iosbel; Fernandez Rondon, Manuel

2005-01-01

The work presents an analysis of the impact of nuclear issue on the Cuban press from 1990 to 2005 that was carried out by a group of communications specialists from nuclear area. An analysis of main challenges and actions of this group, aimed at informing the public the present situation of the Cuban nuclear programme and its perspectives, was also included

The Cuban nuclear program and its Scientific and Technical Infrastructure

International Nuclear Information System (INIS)

Gandarias Cruz, D.; Codorniu Pujals, D.

1995-01-01

The present paper shows the aspects including the Cuban Nuclear Program and underlines its close connection with the strategy of economic, social and scientific technical development in the country, the organizing structure of the Cuban nuclear activity is explained. The application of nuclear techniques and research development activity in the nuclear field are also expressed in detailed in this paper

Virtual Exploration of the Ring Systems Chemical Universe.

Science.gov (United States)

Visini, Ricardo; Arús-Pous, Josep; Awale, Mahendra; Reymond, Jean-Louis

2017-11-27

Here, we explore the chemical space of all virtually possible organic molecules focusing on ring systems, which represent the cyclic cores of organic molecules obtained by removing all acyclic bonds and converting all remaining atoms to carbon. This approach circumvents the combinatorial explosion encountered when enumerating the molecules themselves. We report the chemical universe database GDB4c containing 916 130 ring systems up to four saturated or aromatic rings and maximum ring size of 14 atoms and GDB4c3D containing the corresponding 6 555 929 stereoisomers. Almost all (98.6%) of these ring systems are unknown and represent chiral 3D-shaped macrocycles containing small rings and quaternary centers reminiscent of polycyclic natural products. We envision that GDB4c can serve to select new ring systems from which to design analogs of such natural products. The database is available for download at www.gdb.unibe.ch together with interactive visualization and search tools as a resource for molecular design.

The 1980 Cuban Crisis: Some Observations.

Science.gov (United States)

Copeland, Ronald

1981-01-01

Reviews the history of the 1980 Cuban migration to the United States. Examines policy questions concerning unexpected mass migrations and the way the U.S. government responds. The Haitian immigration is discussed similarly. (Author/APM)

Feasibility evaluation of two solar cooling systems applied to a cuban hotel. Comparative analysis

International Nuclear Information System (INIS)

Díaz Torres, Yamile; Valdivia Nodal, Yarelis; Monteagudo Yanes, José Pedro; Miranda Torres, Yudit

2016-01-01

The article presents an analysis of technical and economic feasibility of using two configurations of solar cooling in a Cuban hotel. HVAC hybrid schemes are: a cooler of ice water vapor compression (chiller) interconnected in parallel with a smaller capacity chiller, first with a solar-powered absorption cooling system (SACS), and then with a photovoltaic cooling system(PSC). Both were simulated taking into account the weather conditions in the region, thermodynamic calculation methodologies and principles that govern these technologies. The results show that the use of these alternatives contributes to reducing energy consumption and the environmental impact of heating, ventilation and air conditioning systems (HVAC). Economic analysis highlights that PCS is more favorable than the SACS taking into account the cooling cost generation (CCG) but energy assessment indicates that SACS has higher thermal performance for the case study to which it is applied. (author)

Photovoltaic Solar Energy as a Chance and a Need for the Development of the Cuban Economy

International Nuclear Information System (INIS)

Casal Rivera, Yanet; Parúas Cuza, Rafael

2017-01-01

The photovoltaic systems connected to the electric network as a great opportunity and a need for the Cuban economy. This works intends to present an analysis of a lot of aspects related to the economic feasibility of using solar energy generated by roof-mounted small photovoltaic systems such as some aspects related to the economic and environmental analysis and their contribution to the National and Township development as well as a study of the costs behaviors and its comparison concerning prices in reference to the normal electric power and the new investments for the minor sells of these systems to common people. Finally there is a proposition of actions to encourage the use of this kind of energy in the different sectors of the Cuban economy. (author)

Synthesis and characterization of Mg-Al-layered double hydroxides intercalated with cubane-1,4-dicarboxylate anions.

Science.gov (United States)

Rezvani, Zolfaghar; Arjomandi Rad, Farzad; Khodam, Fatemeh

2015-01-21

In the present work, Mg2Al-layered double hydroxide (LDH) intercalated with cubane-1,4-dicarboxylate anions was prepared from the reaction of solutions of Mg(ii) and Al(iii) nitrate salts with an alkaline solution of cubane-1,4-dicarboxylic acid by using the coprecipitation method. The successful preparation of a nanohybrid of cubane-1,4-dicarboxylate(cubane-dc) anions with LDH was confirmed by powder X-ray diffraction, FTIR spectroscopy and thermal gravimetric analysis (TGA). The increase in the basal spacing of LDHs from 8.67 Å to 13.40 Å shows that cubane-dc anions were successfully incorporated into the interlayer space. Thermogravimetric analyses confirm that the thermal stability of the intercalated cubane-dc anions is greater than that of the pure form before intercalation because of host-guest interactions involving hydrogen bonds. The interlayer structure, hydrogen bonding, and subsequent distension of LDH compounds containing cubane-dc anions were shown by molecular simulation. The RDF (radial distribution function), mean square displacement (MSD), and self-diffusion coefficient were calculated using the trajectory files on the basis of molecular dynamics (MD) simulations, and the results indicated that the cubane-dc anions were more stable when intercalated into the LDH layers. A good agreement was obtained between calculated and measured X-ray diffraction patterns and between experimental and calculated basal spacings.

Nuclear analytical techniques in Cuban sugar industry

International Nuclear Information System (INIS)

Diaz R, O.; Griffith M, J.

1997-01-01

This paper is a review concerning the application of Nuclear Analytical Techniques in the Cuban sugar industry. The most complete elemental composition of final molasses (34 elements) and natural zeolites (38) this last one employed as an auxiliary agent in sugar technological processe4s has been performed by means of instrumental Neutron Activation Analysis (INAA) and X-Ray Fluorescence Analysis (XRFA). The trace elemental sugar cane soill-plant relationship and elemental composition of different types of Cuban sugar (raw, blanco-directo and refine) were also studied. As a result, valuable information referred to the possibilities of using these products in animal and human foodstuff so as in the other applications are given. (author). 34 refs., 6 figs., 1 tab

Management system for the control of the Educative Project in the Higher Cuban Education

Directory of Open Access Journals (Sweden)

Lionel Rodolfo Baquero Hernández

2016-06-01

Full Text Available As part of the training of Cuban university students involved educational project that requires proper control of compliance. At the University of Information Science, is done through a digital model developed by the professor of the group which generates poor control and directly undermines the quality of the process. In this work the solution to the problem as basis of computerization, using OpenUP development methodology, programming language Java Script on the NetBeans platform version 8.0 as Integrated Development Environment, with ExtJS 3.4 framework is detailed, with version 8.0 of the Software Engineering tools Computer Assisted Visual Paradigm for modeling and PostgreSQL 9.3 as a management system database. The system also generates the associated compliance status of the activities that make up the educational project of a group, which facilitates the control and decision making reports.

People on the Edge See More. A Conversation with the Cuban-American Writer Cristina García

Directory of Open Access Journals (Sweden)

Àngels Carabí

2010-06-01

Full Text Available L'entrevista amb l'escriptora cubano-americana Cristina Garciacute;a explora el tema de la identitat cubanoamericana i desvetlla la riquesa literagrave;ria que sorgeix de la fusioacute; de dues cultures, la cubana i la nord-americana, i com aquesta fusioacute; innova la literatura nord-americana tradicional. En la seva novelmiddot;la, emDreaming in Cuban/em (1992, l'escriptora explora els efectes de la Revolucioacute; castrista des de la perspectiva de les dones cubanes que van quedar-se a l'illa, aixiacute; com de les dones que emigraren als Estats Units. The conversation with Cuban-American writer Cristina Garciacute;a explores what it means to be Cuban-American, and reveals how to grow bicultural enriches mainstream American literature. In her novel emDreaming in Cuban/em (1992, the writer explores the effects of the Castro Revolution from the perspective of Cuban women who remained in Cuba, as well as from the experience of women who emigrated to the United States.

In situ characterization of cofacial Co(IV) centers in Co4O4 cubane: Modeling the high-valent active site in oxygen-evolving catalysts.

Science.gov (United States)

Brodsky, Casey N; Hadt, Ryan G; Hayes, Dugan; Reinhart, Benjamin J; Li, Nancy; Chen, Lin X; Nocera, Daniel G

2017-04-11

The Co 4 O 4 cubane is a representative structural model of oxidic cobalt oxygen-evolving catalysts (Co-OECs). The Co-OECs are active when residing at two oxidation levels above an all-Co(III) resting state. This doubly oxidized Co(IV) 2 state may be captured in a Co(III) 2 (IV) 2 cubane. We demonstrate that the Co(III) 2 (IV) 2 cubane may be electrochemically generated and the electronic properties of this unique high-valent state may be probed by in situ spectroscopy. Intervalence charge-transfer (IVCT) bands in the near-IR are observed for the Co(III) 2 (IV) 2 cubane, and spectroscopic analysis together with electrochemical kinetics measurements reveal a larger reorganization energy and a smaller electron transfer rate constant for the doubly versus singly oxidized cubane. Spectroelectrochemical X-ray absorption data further reveal systematic spectral changes with successive oxidations from the cubane resting state. Electronic structure calculations correlated to experimental data suggest that this state is best represented as a localized, antiferromagnetically coupled Co(IV) 2 dimer. The exchange coupling in the cofacial Co(IV) 2 site allows for parallels to be drawn between the electronic structure of the Co 4 O 4 cubane model system and the high-valent active site of the Co-OEC, with specific emphasis on the manifestation of a doubly oxidized Co(IV) 2 center on O-O bond formation.

‘La Comida Mambisa’: food, farming, and Cuban identity, 1839-1999

Directory of Open Access Journals (Sweden)

Shannon Lee Dawdy

2002-01-01

Full Text Available Describes how Cuba developed a countrywide system of food meaning and production in the mid-19th c. that became a national, and eventually "nationalist", cuisine during Cuba's revolutionary moments. Author explains how the centrality of food within Cuban national identity was strongly related with the valency associated with the subsistence farming on small family farms ("sitios", producing these native foods and Caribbean ingredients, e.g. cassava, guava, and sweet potatoes. The self-sufficiency of these small farmers was in emerging nationalist discourses opposed to the large-scale, export-oriented, colonial plantations and to slavery. Many small family farmers, of which many were ex-slaves, participated in the armed struggles in part to defend their right of independent, subsistence agriculture. Author outlines how since the early, mid-19th-c. Creole nationalism, Creole food and the small farms remained associated with authentic Cuban folk culture and with national identity, and related to independence struggles, and self-sufficiency, including during and after the 1959 Revolution.

Establishment of the exotic invasive Cuban treefrog (Osteopilus septentrionalis) in Louisiana

Science.gov (United States)

Glorioso, Brad M.; Waddle, J. Hardin; Muse, Lindy J.; Jennings, Nicole D.; Litton, Melanie; Hamilton, Joel; Gergen, Steven; Heckard, David

2018-01-01

The Cuban treefrog, Osteopilus septentrionalis, is native to Cuba, the Bahamas, and the Cayman Islands, and is invasive in areas where it has been introduced and established in the Caribbean as well as Florida. Despite repeated occurrences in several states over many years, it was not believed that Cuban treefrogs had successfully established outside of Florida in the mainland United States. From mid-September to mid-November 2017, we captured and removed 367 Cuban treefrogs in just four surveys in New Orleans, Louisiana. The impacts of this population on native treefrogs in this area is unknown but possibly severe as indicated by the paucity of observations of native treefrogs during our surveys. Eradication of this seemingly established population is improbable, but continued surveys will facilitate learning about the ecology and genetics of this novel population.

APS storage ring vacuum system performance

International Nuclear Information System (INIS)

Noonan, J.R.; Gagliano, J.; Goeppner, G.A.

1997-01-01

The Advanced Photon Source (APS) storage ring was designed to operated with 7-GeV, 100-mA positron beam with lifetimes > 20 hours. The lifetime is limited by residual gas scattering and Touschek scattering at this time. Photon-stimulated desorption and microwave power in the rf cavities are the main gas loads. Comparison of actual system gas loads and design calculations will be given. In addition, several special features of the storage ring vacuum system will be presented

Cavity Ring-down Spectroscopic System And Method

KAUST Repository

Alquaity, Awad Bin Saud

2015-05-14

A system and method for cavity ring-down spectroscopy can include a pulsed quantum cascade laser, an optical ring-down cavity, a photodetector, and an oscilloscope. The system and method can produce pulse widths of less than 200 ns with bandwidths greater than 300 pm, as well as provide temporal resolution of greater than 10 .mu.s.

Cavity Ring-down Spectroscopic System And Method

KAUST Repository

Alquaity, Awad Bin Saud; Farooq, Aamir

2015-01-01

A system and method for cavity ring-down spectroscopy can include a pulsed quantum cascade laser, an optical ring-down cavity, a photodetector, and an oscilloscope. The system and method can produce pulse widths of less than 200 ns with bandwidths greater than 300 pm, as well as provide temporal resolution of greater than 10 .mu.s.

Social workers’ construction of “family” in Cuban context: Ideas for a debate

Directory of Open Access Journals (Sweden)

Angela Isabel Peña Farias

2015-12-01

Full Text Available This paper presents preliminary research about the process of the construction of concepts in social work. In this case, it is referred to as a social worker’s construction of “family” as a concept and as a field of practice in a current Cuban context. Based on an exploratory and qualitative research design, the paper presents an analysis that also opens to the discussion about social work with families in Cuba. The findings shows that Cuban social workers think of family as a group with cohabitation and affinity, which is more important than consanguinity, as a dimension for family definitions. They also point at structures of family, special bonds in family network and the social internal and external functions of family in their definitions. Among these functions, the transmission of cultural values, as well as the emotional support and shelter for members, seems relevant.Regarding family as a field of practice, they all share the criteria that is necessary for practice to develop a contextual analysis of each situation that goes from macro-contextual aspects to the micro-reality of family. The importance of structural matters and their impact on family functions is also a common idea, which is nucleated around a multigenerational reality of Cuban families and evaluated as a positive or negative impact depending on the case in question.They consider social work with families, and social work in general, to be in a critical situation in relation to losing professionalization and social recognition. The reasons explaining these ideas have to do with the instability of social work institutionalization and the recent retraction of social services. These variations have obeyed the changes in a Cuban context that affects the entire welfare system and social work’s position in it.

Results of HBsAg examination with immunoelectrophoresis and radioimmunoassay in VPR, Laotian PDR and Cuban R

Energy Technology Data Exchange (ETDEWEB)

Michal, L; Szilagyiova, M; Zahradny, V; Holan, J; Krajnak, V [Komenskeho Univ., Martin (Czechoslovakia). Lekarska Fakulta; Padurova, J [Okresna Hygienicka Stanica, Zilina (Czechoslovakia)

1984-06-21

The results are compared of examining 112 Vietnamese, 30 Laotian and 50 Cuban citizens for HBsAg using IEP and RIA methods. Of the examined persons with no liver disorders HBsAg was found in 23 (31.5%) of the Vietnamese and 1 (2.5%) of the Cubans using the RIA method and only in 4 (5.5%) of the Vietnamese using the IEP method. Of the examined persons with liver disorders RIA found HBsAg in 12 (30.8%) of the Vietnamese, 5 (71.4%) of the Laotians and 2 (20.0%) of the Cubans while with IEP only in 3 (7.7%) Vietnamese 2 (28.6%) Laotians and 1 (10.0%) of the Cubans examined.

Results of HBsAg examination with immunoelectrophoresis a radioimmunoassay in VPR, Laotian PDR and Cuban R

International Nuclear Information System (INIS)

Michal, L.; Szilagyiova, M.; Zahradny, V.; Holan, J.; Krajnak, V.

1984-01-01

The results are compared of examining 112 Vietnamese, 30 Laotian and 50 Cuban citizens for HBsAg using IEP and RIA methods. Of the examined persons with no liver disorders HBsAg was found in 23 (31.5%) of the Vietnamese and 1 (2.5%) of the Cubans using the RIA method and only in 4 (5.5%) of the Vietnamese using the IEP method. Of the examined persons with liver disorders RIA found HBsAg in 12 (30.8%) of the Vietnamese, 5 (71.4%) of the Laotians and 2 (20.0%) of the Cubans while with IEP only in 3 (7.7%) Vietnamese 2 (28.6%) Laotians and 1 (10.0%) of the Cubans examined. (author)

Ethnobotany of pru, a traditional Cuban refreshment

NARCIS (Netherlands)

Volpato, G.; Godínez, D.

2004-01-01

Gouania polygama (Jacq.) Urban, Smilax domingensis Willd., and Pimenta dioica Merr., are three species widely used within Cuban ethnobotanical traditions and practices. Pru is a traditional refreshment and medicinal drink produced by their decoction and fermentation with sugar. It is claimed to have

45 CFR 400.62 - Treatment of eligible secondary migrants, asylees, and Cuban/Haitian entrants.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 2 2010-10-01 2010-10-01 false Treatment of eligible secondary migrants, asylees... secondary migrants, asylees, and Cuban/Haitian entrants. The State and local resettlement agencies must establish procedures to ensure that eligible secondary migrant refugees, asylees, and Cuban/Haitian entrants...

Analysis of policy implications and challenges of the Cuban health assistance program related to human resources for health in the Pacific

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Asante Augustine D

2012-05-01

Full Text Available Abstract Background Cuba has extended its medical cooperation to Pacific Island Countries (PICs by supplying doctors to boost service delivery and offering scholarships for Pacific Islanders to study medicine in Cuba. Given the small populations of PICs, the Cuban engagement could prove particularly significant for health systems development in the region. This paper reviews the magnitude and form of Cuban medical cooperation in the Pacific and analyses its implications for health policy, human resource capacity and overall development assistance for health in the region. Methods We reviewed both published and grey literature on health workforce in the Pacific including health workforce plans and human resource policy documents. Further information was gathered through discussions with key stakeholders involved in health workforce development in the region. Results Cuba formalised its relationship with PICs in September 2008 following the first Cuba-Pacific Islands ministerial meeting. Some 33 Cuban health personnel work in Pacific Island Countries and 177 Pacific island students are studying medicine in Cuba in 2010 with the most extensive engagement in Kiribati, the Solomon Islands, Tuvalu and Vanuatu. The cost of the Cuban medical cooperation to PICs comes in the form of countries providing benefits and paying allowances to in-country Cuban health workers and return airfares for their students in Cuba. This has been seen by some PICs as a cheaper alternative to training doctors in other countries. Conclusions The Cuban engagement with PICs, while smaller than engagement with other countries, presents several opportunities and challenges for health system strengthening in the region. In particular, it allows PICs to increase their health workforce numbers at relatively low cost and extends delivery of health services to remote areas. A key challenge is that with the potential increase in the number of medical doctors, once the local students

Kinanthropometric profile of Cuban women Olympic volleyball champions.

Science.gov (United States)

Carvajal, Wiliam; Betancourt, Hamlet; León, Sofia; Deturnel, Yanel; Martínez, Miriam; Echevarría, Ivis; Castillo, María Eugenia; Serviat, Noemí

2012-04-01

Athletes' kinanthropometric profiles are widely addressed in the scientific literature. Such profiles are particularly important in volleyball because absolute size contributes a significant percentage of total variance associated with athletic success. As in other team sports, volleyball players' kinanthropometric attributes correlate with the game's tactical demands. From 1992 through 2000, the Cuban women's volleyball team achieved top global performance, winning first place in three successive Summer Olympic Games. Describe the kinanthropometric profiles of Cuban women Olympic volleyball champions during 1992-2000 and compare these by position played. Measurements were taken of body composition, somatotype, proportionality and several anthropometric indicators in 41 Cuban women volleyball players, grouped by playing position. All were members of the national team that participated in the Summer Olympic Games in Barcelona (1992), Atlanta (1996) and Sydney (2000). Mean and standard deviations were calculated for all study variables. Analysis of variance was used to compare means for different positions for the variables weight; height; percent adipose, muscle and bone mass; body mass index; and muscle-to-bone ratio. Discriminant analysis was performed to identify anthropometric dimensions differentiating playing positions (center, spiker and setter), using pvolleyball players was balanced mesomorphic (2.7-3.6-2.9). Classified by position, centers (2.9-3.4-3.4) and spikers (2.8-3.6-2.9) presented an average mesomorphic-ectomorphic somatotype, and setters (2.6-3.7-2.6) were balanced mesomorphic. On assessing Somatotype Attitudinal Mean (SAM), centers and spikers showed more intrapositional homogeneity than that of setters. Centers were significantly taller (187.1±2.5 cm) than players in other positions. Centers' percent adipose tissue mass (28.9±2.7%) was significantly higher than that of setters (24.3±2.7%), who were leanest of all positions. The

Mexican and Cuban Composers in New York City circa 1880-1920

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John Koegel

2006-10-01

Full Text Available Cuban musicians active in New  York in the 1860s through the 1890s such as Ignacio Cervantes, Emilio Agramonte, and Rosalia Chalia assisted in the struggle for Cuban independence from Spain from the vantage point of New York's Cuban émigré community, and they also established  a strong  presence in the city's musical life.  Important Mexican musicians such as Miguel Lerdo  de Tejada and Carlos Curti intermittently visited New York or were long-term residents there. This was especially true during the late- nineteenth century, when the forced political stability during the Porfiriato made possible the extended visits of Mexican musicians and ensembles to North American cities such as New York. The Mexican Revolution also sent Mexican musicians to the United States in search of political freedom as well as economic and artistic opportunities that were temporarily closed to them in Mexico.

(Re) framing the nation : the Afro -Cuban challenge to Black and Latino struggles for American identity

OpenAIRE

Gosin, Monika

2009-01-01

This dissertation interrogates the complexity of late 20th and early 21st century racial projects, focusing on conflict and convergence among African Americans, Cuban exiles, and Afro-Cubans in the United States. A textual analysis of the African American Miami Times and the Spanish language El Herald/El Nuevo Herald during the 1980 Mariel exodus and 1994 Balsero crisis, reveals the concerns of Miami African Americans and Cubans related to issues of race, immigration, and national belonging. ...

The cooperative identity in the cuban constitution. Currents challenges

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Orestes Rodríguez Musa

2013-12-01

Full Text Available The work contribute with some valuations about the conception of the cooperative in the Cuban constitutionalism, with the purpose that the constitution can guide -like it corresponds- the legal implementation of the figure toward an integral perspective. To accomplish this goal, this article offers a characterization of the institution that illustrates about its identity. Then it analyzed the juridical dimension of the cooperative, pondering the different doctrinal postures that have tried to define its nature. Lastly, it argue that the current laws of the Cuban Constitution, influenced by a reduced conception of the institution, suffers some limitations that block the good use of the figure in a socioeconomic context in which it is called to transcend.

The Conversion of Wiswesser Line Notations to Ring Codes. I. The Conversion of Ring Systems

Science.gov (United States)

Granito, Charles E.; And Others

1972-01-01

The computerized conversion of Wiswesser Line Notations to Ring Codes, using a two-part approach, and the set of computer programs generated for the conversion of ring systems are described. (9 references) (Author)

Validation of the Cuban Version of Addenbrooke's Cognitive Examination-Revised for Screening Mild Cognitive Impairment.

Science.gov (United States)

Broche-Pérez, Yunier; López-Pujol, Héctor Alejandro

2017-01-01

The diagnostic accuracy of the Cuban version of the revised Addenbrooke's Cognitive Examination (ACE-R) in identifying mild cognitive impairment (MCI) in comparison with the Mini-Mental State Examination (MMSE) was assessed. The Cuban ACE-R was administered to a group of 129 elderly subjects (92 cognitively healthy and 37 subjects with MCI). The t tests for independent samples were used to compare scores of different psychometric scales between groups, and effect sizes (Cohen's d) were calculated. Cronbach's coefficient α was used to evaluate the reliability of psychometric scales. The validity of ACE-R to screen for MCI was assessed by receiver operating characteristic (ROC) curves. The Cuban ACE-R had reliable internal consistency (Cronbach's coefficient α = 0. 879). The optimal cut-off score for ACE-R for detecting MCI was 84/85. The sensitivity and specificity of ACE-R to screen for MCI was superior to those of MMSE. The area under the ROC curve of the Cuban ACE-R was much larger than that of MMSE (0.93 and 0.63) for detecting MCI. The Cuban ACE-R is a valid screening tool for detecting cognitive impairment. It is more sensitive and accurate in screening for MCI than MMSE. © 2018 S. Karger AG, Basel.

A ring system detected around the Centaur (10199) Chariklo.

Science.gov (United States)

Braga-Ribas, F; Sicardy, B; Ortiz, J L; Snodgrass, C; Roques, F; Vieira-Martins, R; Camargo, J I B; Assafin, M; Duffard, R; Jehin, E; Pollock, J; Leiva, R; Emilio, M; Machado, D I; Colazo, C; Lellouch, E; Skottfelt, J; Gillon, M; Ligier, N; Maquet, L; Benedetti-Rossi, G; Ramos Gomes, A; Kervella, P; Monteiro, H; Sfair, R; El Moutamid, M; Tancredi, G; Spagnotto, J; Maury, A; Morales, N; Gil-Hutton, R; Roland, S; Ceretta, A; Gu, S-h; Wang, X-b; Harpsøe, K; Rabus, M; Manfroid, J; Opitom, C; Vanzi, L; Mehret, L; Lorenzini, L; Schneiter, E M; Melia, R; Lecacheux, J; Colas, F; Vachier, F; Widemann, T; Almenares, L; Sandness, R G; Char, F; Perez, V; Lemos, P; Martinez, N; Jørgensen, U G; Dominik, M; Roig, F; Reichart, D E; LaCluyze, A P; Haislip, J B; Ivarsen, K M; Moore, J P; Frank, N R; Lambas, D G

2014-04-03

Hitherto, rings have been found exclusively around the four giant planets in the Solar System. Rings are natural laboratories in which to study dynamical processes analogous to those that take place during the formation of planetary systems and galaxies. Their presence also tells us about the origin and evolution of the body they encircle. Here we report observations of a multichord stellar occultation that revealed the presence of a ring system around (10199) Chariklo, which is a Centaur--that is, one of a class of small objects orbiting primarily between Jupiter and Neptune--with an equivalent radius of 124 ±  9 kilometres (ref. 2). There are two dense rings, with respective widths of about 7 and 3 kilometres, optical depths of 0.4 and 0.06, and orbital radii of 391 and 405 kilometres. The present orientation of the ring is consistent with an edge-on geometry in 2008, which provides a simple explanation for the dimming of the Chariklo system between 1997 and 2008, and for the gradual disappearance of ice and other absorption features in its spectrum over the same period. This implies that the rings are partly composed of water ice. They may be the remnants of a debris disk, possibly confined by embedded, kilometre-sized satellites.

Quantized levitation states of superconducting multiple-ring systems

International Nuclear Information System (INIS)

Haley, S.B.; Fink, H.J.

1996-01-01

The quantized levitation, trapped, and suspension states of a magnetic microsphere held in equilibrium by two fixed superconducting (SC) microrings are calculated by minimizing the free energy of the system. Each state is a discrete function of two independent fluxoid quantum numbers of the rings. When the radii of the SC rings are of the same order as the Ginzburg-Landau coherence length ξ(T), the system exhibits a small set of gravity and temperature-dependent levels. The levels of a weakly magnetized particle are sensitive functions of the gravitational field, indicating potential application as an accelerometer, and for trapping small magnetic particles in outer space or on Earth. The equilibrium states of a SC ring levitated by another SC ring are also calculated. copyright 1996 The American Physical Society

Human motivation by some Cuban theorists

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Luis Alfredo González Collera

2010-06-01

Full Text Available The current article offers a summary of the theories of three outstanding Cuban psychologists, whic h have contributed with important knowledge to the motivational sphere of personality. These theoretical approaches constitute the epistemology of base to new studies about motivation in any area of knowledge, although they have a special emphasis on the educative and pedagogic area as well as on the personal development.

O-Ring sealing arrangements for ultra-high vacuum systems

Science.gov (United States)

Kim, Chang-Kyo; Flaherty, Robert

1981-01-01

An all metal reusable O-ring sealing arrangement for sealing two concentric tubes in an ultra-high vacuum system. An O-ring of a heat recoverable alloy such as Nitinol is concentrically positioned between protruding sealing rings of the concentric tubes. The O-ring is installed between the tubes while in a stressed martensitic state and is made to undergo a thermally induced transformation to an austenitic state. During the transformation the O-ring expands outwardly and contracts inwardly toward a previously sized austenitic configuration, thereby sealing against the protruding sealing rings of the concentric tubes.

Some historical tendencies of the methodological work direction in the education municipal level at the cuban context

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Orlando Ramos-Álvarez

2017-11-01

Full Text Available This work leaves from the theoretical and empiric systematizing that shows the necessity to investigate how it has evolved and what factors they have conditioned the behavior of the methodological work direction in the education municipal level. The basic budgets of the educational are approached that serve of referents for the analysis of the relationships of the organizational functional levels of the methodological work. The study is carried out in the period 1959-2017, starting in 1959 as an important milestone in the conception of the Cuban educational system. When the Revolution triumphed there were two conceptions of Education, in Cuban educational practice, on the one hand the abandoned national education system, essentially pragmatic, totally incongruous and on the other the aspirations of the Revolutionary Government, which had been forged in the revolutionary struggle between 1953 and 1959.

Taxonomic status and biology of the Cuban blackhawk, Buteogallus anthracinus gundlachii (AVES: Accipitridae)

Science.gov (United States)

Wiley, J.W.; Garrido, O.H.

2005-01-01

We reevaluate the taxonomic status of the Cuban population of the Common Black-Hawk (Buteogallus anthracinus) based on our examination of additional specimens, nests, eggs, and voice data. Buteogallus a. gundlachii is smaller than mainland populations of anthracinus and differs from mainland birds in plumage coloration and pattern. The common (alarm) call of gundlachii is a series of three or four notes, differing from that of mainland anthracinus, whose call consists of 9-24 notes. In the Isla de Pinos, Cuba, we observed gundlachii eating two species of land crabs (71.4%), centipedes (7.1%), lizards (10.7%), mammals (7.1%), and a bird (3.6%). We consider Buteogallus gundlachii Cabanis 1854 (1855), the Cuban Black-Hawk, to be a full species, endemic to Cuba, Isla de Pinos, and many of the cays of the Cuban Archipelago. ?? 2005 The Raptor Research Foundation, Inc.

Prendas-Ngangas-Enquisos: turbulence and the influence of the dead in Cuban-Kongo material culture.

Science.gov (United States)

Ochoa, Todd Ramón

2010-01-01

Cuban-Kongo praise of the dead in Havana turns insistently around complex agglomerations of materials called "prendas,"ngangas," and "enquisos." This article addresses the ontological status of "prendas-ngangas-enquisos," which practitioners of Cuban-Kongo affliction practices care for as entities that determine the very possibility of their healing and harming craft. Cuban-Kongo societies of affliction, in Havana collectively referred to as "Palo," stake their claim to influence others in and through these entities. In this essay I seek to position the influence generated in prendas-ngangas-enquisos as a problem for Euro-American materialism, to be addressed not through symbolic or representational solutions but, rather, by refocusing the problem itself via alternate distributions of its epistemological, historical, and ethnographic elements. Contextualized within ethnographic description, I first propose that prendas-ngangas-enquisos do not conform to dialectical logic, and should thus be positioned conceptually as something other than "objects" or "fetishes." From there, I consider Creole turns on the term prenda and explore scholarly accounts of 19th-century Cuban slavery and manumission, which I place alongside what is known about pawn slavery among BaKongo people prior to and during the Atlantic slave trade. Having established a basic series of conceptual and historiographic coordinates, I then suggest ethnographically how prendas-ngangas-enquisos come to command others, thereby guaranteeing Cuban-Kongo healing and harming sovereignty in Cuba today.

Pedagogical professional training in Cuban educative context

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Mayre Acosta Calderón

2015-05-01

Full Text Available The conception of the pedagogical professional training has evolved alongside with the educative changes that have taken place in the history of Cuban education. This research was intended to examine the evolution of professional training from the foundation of colleges of Education to the present. The study takes into account the relation of the instructive, educative and developing aspects; the development of the professional needs and their influence on cognitive and formative activity of learners and their professional performance; the components of contents included in the evaluation of the professional competence; and the comprehensive disciplinary approach of the formation process. Thus, this investigation is aimed at providing a historical analysis of the development of the pedagogical professional training, illustrating the continuity of the formative process in Cuban context. This study revealed the main trends of the pedagogical professional training for the General Senior High Education, It shows the movement from a former segmentation of instructive and educative components and emotional and intellectual educations to a and interconnected approach of both processes.

Gamma radiation effects on the cuban antimeningococcic BC vaccine

International Nuclear Information System (INIS)

Padron Soler, E.; Romay Penabad, Z.; Le Riveran Morales, E.; Campa Huergo, C.; Sierra Gonzalez, G.; Alfalla Valdes, L.; Prieto Miranda, E.

1994-01-01

The effects of gamma rays on the Cuban antimeningococcic BC vaccine properties were studied. These were performanced by simulation with different bio burden of microbial pollutants. The isolated spores of the pollutants of non- aseptic areas were used. Its D10 was determined as 2.045 Gy. On that basis, the sterilization dose setting was performed. The quality of the irradiated vaccine was performed according to the Cuban standards: sterility, protein and polysaccharide concentration, immunogenicity, per cent of protein adsorption, nonspecific innocuousness. There were observed non negative effects on the vaccine of the radiation process in the dose range of 0-25 Gy. It was also studied the preservation of the properties of the irradiated vaccine, by storing it during one year at four celsius grade. The results were satisfactory

Methodology of Competences Management Assuming the Cuban Norm about Management of Human Capital

OpenAIRE

Santos, Armando Cuesta

2011-01-01

An applied research conducted in eight Cuban companies which follow the approach of skills in strategic management of human resources according to the standard Cuban CN: 3000-3002:2007 on human capital management, seeking a superior performance to higher productivity. It sought to manage the connection of individual work with the responsibilities for the strategic organizational performance. As a result we have obtained a metodology to manage the various skill levels expressed in this compani...

[The migration crisis of the summer of 1994. Balance and perspectives of Cuban emigration flows: 1984-1996].

Science.gov (United States)

Rodriguez Chavez, E

1996-01-01

"The article argues that the rafters crisis of 1994 and the resulting migration agreements between the United States and Cuba in 1994 and 1995 were a radical turn in policies and migration flows between the two countries. The article also describes the general evolution of Cuban migration flows towards the U.S. from the 1984 bilateral agreement up to 1996. As a context, it describes the structural elements of recent Cuban emigration and the place Cubans occupy in the general immigration from Latin America and the Caribbean." (EXCERPT)

An Automatic Assembling System for Sealing Rings Based on Machine Vision

Directory of Open Access Journals (Sweden)

Mingyu Gao

2017-01-01

Full Text Available In order to grab and place the sealing rings of battery lid quickly and accurately, an automatic assembling system for sealing rings based on machine vision is developed in this paper. The whole system is composed of the light sources, cameras, industrial control units, and a 4-degree-of-freedom industrial robot. Specifically, the sealing rings are recognized and located automatically with the machine vision module. Then industrial robot is controlled for grabbing the sealing rings dynamically under the joint work of multiple control units and visual feedback. Furthermore, the coordinates of the fast-moving battery lid are tracked by the machine vision module. Finally the sealing rings are placed on the sealing ports of battery lid accurately and automatically. Experimental results demonstrate that the proposed system can grab the sealing rings and place them on the sealing port of the fast-moving battery lid successfully. More importantly, the proposed system can improve the efficiency of the battery production line obviously.

A scenario analysis of investment options for the Cuban power sector using the MARKAL model

International Nuclear Information System (INIS)

Wright, Evelyn L.; Belt, Juan A.B.; Chambers, Adam; Delaquil, Pat; Goldstein, Gary

2010-01-01

The Cuban power sector faces a need for extensive investment in new generating capacity, under a large number of uncertainties regarding future conditions, including: rate of demand growth, fluctuations in fuel prices, access to imported fuel, and access to investment capital for construction of new power plants and development of fuel import infrastructure. To identify cost effective investment strategies under these uncertainties, a supply and power sector MARKAL model was assembled, following an extensive review of available data on the Cuban power system and resource potentials. Two scenarios were assessed, a business-as-usual (BAU) scenario assuming continued moderate electricity load growth and domestic fuel production growth, and a high growth (HI) scenario assuming rapid electricity demand growth, rapid increase in domestic fuel production, and a transition to market pricing of electricity. Within these two scenarios sets, sensitivity analyses were conducted on a number of variables. The implications of least-cost investment strategies for new capacity builds, investment spending requirements, electricity prices, fuel expenditures, and carbon dioxide emissions for each scenario were assessed. Natural gas was found to be the cost effective fuel for new generation across both scenarios and most sensitivity cases, suggesting that access to natural gas, through increased domestic production and LNG import, is a clear priority for further analysis in the Cuban context.

A scenario analysis of investment options for the Cuban power sector using the MARKAL model

Energy Technology Data Exchange (ETDEWEB)

Wright, Evelyn L.; Chambers, Adam; Delaquil, Pat; Goldstein, Gary [International Resources Group, 1211 Connecticut Avenue, NW, Suite 700, Washington, DC 20036 (United States); Belt, Juan A.B. [US Agency for International Development, 1300 Pennsylvania Avenue, NW, Washington, DC 20523-3800 (United States)

2010-07-15

The Cuban power sector faces a need for extensive investment in new generating capacity, under a large number of uncertainties regarding future conditions, including: rate of demand growth, fluctuations in fuel prices, access to imported fuel, and access to investment capital for construction of new power plants and development of fuel import infrastructure. To identify cost effective investment strategies under these uncertainties, a supply and power sector MARKAL model was assembled, following an extensive review of available data on the Cuban power system and resource potentials. Two scenarios were assessed, a business-as-usual (BAU) scenario assuming continued moderate electricity load growth and domestic fuel production growth, and a high growth (HI) scenario assuming rapid electricity demand growth, rapid increase in domestic fuel production, and a transition to market pricing of electricity. Within these two scenarios sets, sensitivity analyses were conducted on a number of variables. The implications of least-cost investment strategies for new capacity builds, investment spending requirements, electricity prices, fuel expenditures, and carbon dioxide emissions for each scenario were assessed. Natural gas was found to be the cost effective fuel for new generation across both scenarios and most sensitivity cases, suggesting that access to natural gas, through increased domestic production and LNG import, is a clear priority for further analysis in the Cuban context. (author)

Preparation of high temperature superconductor ceramics using cuban reactives. Optimization of the synthesis method

International Nuclear Information System (INIS)

Leyva Fabelo, A.; Cruz, C.; Aragon, B.; Suarez, J.C.; Mora, M.

1991-01-01

Results of the crystallographic characterization of a group of Cuban Products, which are evaluated to be employed in HTSC fabrication are presented in this paper. The first results on the synthesis of HTSC (RBa 2 Cu 3 0 7δ , R= Y, La, Nd) using Cuban reactives, are presented. The so called 'solid state reaction method of synthesis' was optimized, obtaining a critical temperature of more than 93 k

Fano and Dicke effects in a double Rashba-ring system

International Nuclear Information System (INIS)

Apel, V M; Orellana, P A; Pacheco, M

2008-01-01

The electronic transport in a system of two quantum rings side-coupled to a quantum wire is studied via a single-band tunneling tight-binding Hamiltonian. We derived analytical expressions for the conductance and spin polarization when the rings are threaded by magnetic fluxes with Rashba spin-orbit interaction. We show that by using the Fano and Dicke effects this system can be used as an efficient spin filter even for small spin-orbit interaction and small values of magnetic fluxes. We compare the spin-dependent polarization of this design and the polarization obtained with one ring side-coupled to a quantum ring. As a main result, we find better spin polarization capabilities as compared to the one-ring design

Analysis of the potentiality for implementing of the cleaner production and adopting a sustainable consumption in the Cuban entrepreneurial system

International Nuclear Information System (INIS)

Tortosa Ferrer, Barbara Ivette; Orue Valdes, Sonia; Mena Ulecia, Karel

2007-01-01

The world economic development has conduced to increase the worsening of the environment as result of the natural resources pollution. The tendency has been toward the unsustainable exploitation of natural resources, to increasing of the goods and services production, as well as, to elevated consumption. In this sense, many countries have planed environmental policies addressed to reducing of pollution introducing cleaner production practices and promoting the adoption of responsible consumption. This article shows the existing potentiality in a selected Cuban companies group for introducing and applying of the cleaner production, as well as, the adoption of a sustainable consumption start from analysis of the obtained results in short-term assessments (quick scans) carried out by the Cuban Environment Agency Focal Point of the National Cleaner Production Network in the period between 2004 and 2007

CORRECTION SYSTEMS UPGRADE FOR THE SNS RING

International Nuclear Information System (INIS)

PAPAPHILIPPOU, Y.; GARDNER, C.J.; LEE, Y.Y.; WEI, J.

2001-01-01

In view of the changes in the design of the SNS ring from the original FODO lattice [l] to the 220m hybrid lattice [2] and finally 1.3GeV compatible 248m ring [3], complementary studies have been undertaken, in order to upgrade its correction packages. We review the evolution of the correction systems and present the accelerator physics studies for the adopted schemes and powering plan

The education in values on professionals´ formation from a cuban perspective

Directory of Open Access Journals (Sweden)

Bárbara del C. Roba Lazo

2014-12-01

Full Text Available The education in values has been a topic broadly approached in the last decades by authors of different latitudes. In the social development, this constitutes a great problem in the formation of the individuals to who, the social relationships allow them to value, to transform the reality and to be educated, what leads to the formation of the personality. The Cuban universities, as entities open to the society, win more and more partisans in the conception that their purpose is not only to transmit knowledge in its closed environment, but on the contrary, they represent a main socialized agent of education in values aware of the social mission that has given to it by the society that is built, like a formative institution able to solve the necessities of the society. For that reason, it is demanded the integral formation of the professionals. In the work it is approached the education in values from the perspective o the current Cuban society necessities that demands the development of a humanist pedagogy sustained in axiological bases that defend a new pedagogic ethics. It is carried out an analysis of the socialized agencies and the agents in charge of this process, as well as the historical antecedents of the education in values from the Cuban point of view in the different contexts the topic has been studied, as well as the contributions from the Cuban pedagogy to the development of it, indispensable from the integral formation of the Physical Culture professionals.

The injection system of the stretcher ring ELSA

International Nuclear Information System (INIS)

Dreist, A.

1989-07-01

For the stretcher ring ELSA in the framwork of this thesis an injection system has been concipated and constructed which should allow all projected operational modes of this stretcher ring, the stretcher, the post-acceleration, and the accumulation mode. The proof could be performed that the realized concept allows all these operational modes. Furthermore it could be shown that the injection shifted from the equilibrium orbit has no disadvantageous effects on a uniform extraction and by this on a high touching ratio. In fact it is even possible to apply the decay of the coherent betatron oscillations around the equilibrium orbit, caused by injection of the incident beam shifted from the equilibrium orbit, to diagnosis purposes: By reproduction of this damping process in a simulation model statements on nonlinearities present in the ring and by this statements on the actual phase-space structure are possible. It has so been shown that the concept presented in this thesis and realized for this thesis represents a suited injection system for the stretcher ring ELSA. (orig.) [de

Cuban entities management. Cedrux just around the corner.

Directory of Open Access Journals (Sweden)

Tamara Rodríguez Sánchez

2011-12-01

Full Text Available The direction of the country as part of strengthening entities management and the informatization of Cuban society, presented the need to create a System of Enterprise Resource Planning (ERP, which would be able to computerize management processes of business and budgeted entities on national scale. It is in this way that since July 2008 CEDRUX product was developed composed by 15 subsystems. It will constitute the core on which new solutions will be developed that will extend its functionalities in a constantly way, including new entities management processes and allowing constant updating. In its first operational phase that will be in this very year 2011, Cedrux will only integrate 9 subsystems that will answer the economic needs of any organization.

Determination of rare earth elements in sea sediments from the Cuban northwestern coast by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Capote Rodriguez, G.; Perez Zayas, G.; Pena Fortes, B.; Diaz Riso, O.; Hernandez Rivero, A.T.

1998-01-01

The multielemental characterization of sea sediments from an important Cuban coast was performed using instrumental Neutron activation analysis. The obtained results shown an impoverishment of in the studied zone, in comparison with the data taken from other Cuban coaster zones

Making sense of Santería: three books on Afro-Cuban religion

Directory of Open Access Journals (Sweden)

Stephan Palmié

1996-07-01

Full Text Available [First paragraph] Santeria from Africa to the New World: The Dead Sell Memories. GEORGE BRANDON. Bloomington: Indiana University Press, 1993. x + 206 pp. (Cloth US$31.50 Working the Spirit: Ceremonies of the African Diaspora. JOSEPH M. MURPHY. Boston: Beacon, 1994. xiii + 263 pp. (Cloth US$ 25.00 Walking with the Night: The Afro-Cuban World of Santeria. RAUL CANIZARES. Rochester VT: Destiny Books, 1993. xii + 148 pp. (Paper US$ 12.95 Since 1959, the steady exodus from revolutionary Cuba has led to the gradual emergence of an Afro-Cuban religious diaspora in the United States. While this phenomenon has attracted scholarly attention for some time, the literature has grown particularly rapidly in recent years. It is, perhaps, not entirely fortuitous that a spate of current academic publications on the subject coincided with a scramble by the popular media to exploit its exotic potential in the context of the 1993 U.S. Supreme Court case on animal sacrifice. Clearly, what has come to be called an Afro-Cuban "cultic renaissance" in exile holds promise both for sensationalist journalism and certain kinds of theoretical projects. Partly articulating with older, but politically reinvigorated debates about the relations between African and African-American cultures, partly addressing fundamental questions about conventional models of cultural boundedness and coherence, and, finally, calling into question both popular and academic notions of "modernity" (and its inevitable counterpart "tradition", the 292 New West Indian Guide/Nieuwe West-Indische Gids vol. 70 no. 3 &4 (1996problems posed by the emergence of an Afro-Cuban religious diaspora in the United States present a timely challenge.

Customization and the Common Good: A Conversation with Larry Cuban.

Science.gov (United States)

Willis, Scott

2002-01-01

A conversation with Larry Cuban, Professor Emeritus of Education at Stanford University, about two contradictory trends in education: customization and standardization and their effect on the public schools' responsibilities to provide both individual and social benefits. (PKP)

31 CFR 515.546 - Accounts of Cuban sole proprietorships.

Science.gov (United States)

2010-07-01

... proprietorships. Specific licenses are issued unblocking sole proprietorships established under the laws of Cuba... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Accounts of Cuban sole proprietorships. 515.546 Section 515.546 Money and Finance: Treasury Regulations Relating to Money and Finance...

Insularity in “el sueño de las formas”: Divination of Cubanness in the poetic of Gaston Baquero

OpenAIRE

Águila Ajón, Marta

2012-01-01

This study explores the markers of Cuban identity in the poem Brandeburgo 1526 written by Gaston Baquero (La Habana 1914 - Madrid, 1997). The poet is one of the most powerful voices of the Origenes group and of Cuban Literaturel. The exploration I propose does not stem from a previous conceptualization of what constitutes Cubanness, but rather follows Cintio Vitier’s proposal from Lo cubano en la poesía. My study aims for a sensitive intuition of national identity  markers. “Brandeburgo 1526”...

Structure, thermodynamic and electronic properties of carbon-nitrogen cubanes and protonated polynitrogen cations

Science.gov (United States)

Chaban, Vitaly V.; Andreeva, Nadezhda A.

2017-12-01

Energy generation and storage are at the center of modern civilization. Energetic materials constitute quite a large class of compounds with a high amount of stored chemical energy that can be released. We hereby use a combination of quantum chemistry methods to investigate feasibility and properties of carbon-nitrogen cubanes and multi-charged polynitrogen cations in the context of their synthesis and application as unprecedented energetic materials. We show that the stored energy increases gradually with the nitrogen content increase. Nitrogen-poor cubanes retain their stabilities in vacuum, even at elevated temperatures. Such molecules will be probably synthesized at some point. In turn, polynitrogen cations are highly unstable, except N8H+, despite they are isoelectronic to all-carbon cubane. Kinetic stability of the cation decays drastically as its total charge increases. High-level thermodynamic calculations revealed that large amounts of energy are liberated upon decompositions of polynitrogen cations, which produce molecular nitrogen, acetylene, and protons. The present results bring a substantial insights to the design of novel high-energy compounds.

Saturn Rings Origin: Quantum Trapping of Superconducting Iced Particles and Meissner Effect Lead to the Stable Rings System

Science.gov (United States)

Viktorovich Tchernyi, Vladimir

2018-06-01

Saturn Rings Origin: Quantum Trapping of Superconducting Iced Particles and Meissner Effect Lead to the Stable Rings System Vladimir V. Tchernyi (Cherny), Andrew Yu. Pospelov Modern Science Institute, SAIBR, Moscow, Russia. E-mail: chernyv@bk.ruAbstractIt is demonstrated how superconducting iced particles of the protoplanetary cloud of Saturn are coming to magnetic equator plane and create the stable enough rings disk. There are two steps. First, after appearance of the Saturn magnetic field due to Meissner phenomenon all particles orbits are moving to the magnetic equator plane. Finally they become distributed as rings and gaps like iron particles around magnet on laboratory table. And they are separated from each other by the magnetic field expelled from them. It takes up to few tens of thousands years with ten meters rings disk thickness. Second, due to their quantum trapping all particles become to be trapped within magnetic well at the magnetic equator plane due to Abrikosov vortex for superconductor. It works even when particles have small fraction of superconductor. During the rings evolution some contribution to the disk also could come from the collision-generated debris of the current moon and from the geysers like it happened due to magnetic coupling of Saturn and Enceladus. The rings are relict of the early days of the magnetic field of Saturn system.

Rings in drugs.

Science.gov (United States)

Taylor, Richard D; MacCoss, Malcolm; Lawson, Alastair D G

2014-07-24

We have analyzed the rings, ring systems, and frameworks in drugs listed in the FDA Orange Book to understand the frequency, timelines, molecular property space, and the application of these rings in different therapeutic areas and target classes. This analysis shows that there are only 351 ring systems and 1197 frameworks in drugs that came onto the market before 2013. Furthermore, on average six new ring systems enter drug space each year and approximately 28% of new drugs contain a new ring system. Moreover, it is very unusual for a drug to contain more than one new ring system and the majority of the most frequently used ring systems (83%) were first used in drugs developed prior to 1983. These observations give insight into the chemical novelty of drugs and potentially efficient ways to assess compound libraries and develop compounds from hit identification to lead optimization and beyond.

US and Cuban Scientists Forge Collaboration on Arbovirus Research.

Science.gov (United States)

Pérez-Ávila, Jorge; Guzmán-Tirado, Maria G; Fraga-Nodarse, Jorge; Handley, Gray; Meegan, James; Pelegrino-Martínez de la Cotera, Jose L; Fauci, Anthony S

2018-04-01

After December 17, 2014, when the US and Cuban governments announced their intent to restore relations, the two countries participated in various exchange activities in an effort to encourage cooperation in public health, health research and biomedical sciences. The conference entitled Exploring Opportunities for Arbovirus Research Collaboration, hosted at Havana's Hotel Nacional, was part of these efforts and was the first major US-Cuban scientific conference in over 50 years. Its purpose was to share information about current arbovirus research and recent findings, and to explore opportunities for future joint research. The nearly 100 participants included leading arbovirus and vector transmission experts from ten US academic institutions, NIH, CDC, FDA and the US Department of Defense. Cuban participants included researchers, clinicians and students from Cuba's Ministry of Public Health, Pedro Kourí Tropical Medicine Institute, Center for Genetic Engineering and Biotechnology, Center for State Control of Medicines and Medical Devices and other health research and regulatory organizations. Topics highlighted at the three-day meeting included surveillance, research and epidemiology; pathogenesis, immunology and virology; treatment and diagnosis; vector biology and control; vaccine development and clinical trials; and regulatory matters. Concurrent breakout discussions focused on novel vector control, nonvector transmission, community engagement, Zika in pregnancy, and workforce development. Following the conference, the Pedro Kourí Tropical Medicine Institute and the US National Institute of Allergic and Infectious Diseases have continued to explore ways to encourage and support scientists in Cuba and the USA who wish to pursue arbovirus research cooperation to advance scientific discovery to improve disease prevention and control. KEYWORDS Arboviruses, flavivirus, Zika virus, chikungunya virus, dengue virus, research, disease vectors, Cuba, USA.

Enhanced biodegradation of Pina Cuban crude oil by a culture of mixed marine bacteria

Energy Technology Data Exchange (ETDEWEB)

Joseph, I.N.; Perigo, E. [Ministry of Science. Inst. of Oceanography, La Habana (Cuba); Bergueiro, J.R.; Pita, A.; Mayol, M.A. [Balearic Island Univ., Palma de Mallorca, Islas Baleares (Spain); Navarro, A. [Ministry of Industry, Oil Research Center, La Habana (Cuba)

1998-09-01

The ability of a mixed marine bacteria culture to degrade Pina Cuban crude oil in the presence of nutrients and sea water was studied. Laboratory experiments were conducted in flasks with 100 ml of saline liquid containing 1 per cent crude. The flasks were inoculated with marine bacteria (IDO-225, IDO-226, and IDO-229) at a final concentration of 10{sup 6} cell/ml. The cultures were grown at 29 degrees C for 21 days. Bacterial growth, and surface and interfacial tension were measured after 5, 13 and 21 days. Results showed that the marine bacteria were effective in accelerating the biodegradation process of Pina Cuban oil. The efficiency of the process increased when nutrients were added to the system. This biopreparation also accelerated emulsification of the oil without any negative effects to the natural microbiota. The biological oxygen demand at five days and at the end of the experiment was determined. The biodegradation constant and the biochemical stabilization constant were also measured. 14 refs., 5 tabs., 4 figs.

Enhanced biodegradation of Pina Cuban crude oil by a culture of mixed marine bacteria

International Nuclear Information System (INIS)

Joseph, I.N.; Perigo, E.; Bergueiro, J.R.; Pita, A.; Mayol, M.A.; Navarro, A.

1998-01-01

The ability of a mixed marine bacteria culture to degrade Pina Cuban crude oil in the presence of nutrients and sea water was studied. Laboratory experiments were conducted in flasks with 100 ml of saline liquid containing 1 per cent crude. The flasks were inoculated with marine bacteria (IDO-225, IDO-226, and IDO-229) at a final concentration of 10 6 cell/ml. The cultures were grown at 29 degrees C for 21 days. Bacterial growth, and surface and interfacial tension were measured after 5, 13 and 21 days. Results showed that the marine bacteria were effective in accelerating the biodegradation process of Pina Cuban oil. The efficiency of the process increased when nutrients were added to the system. This biopreparation also accelerated emulsification of the oil without any negative effects to the natural microbiota. The biological oxygen demand at five days and at the end of the experiment was determined. The biodegradation constant and the biochemical stabilization constant were also measured. 14 refs., 5 tabs., 4 figs

Sugarcane energy use: The Cuban case

Energy Technology Data Exchange (ETDEWEB)

Alonso-Pippo, Walfrido; Luengo, Carlos A. [Grupo Combustiveis Alternativos, DFA/IFGW/UNICAMP, CP 6165, CEP 13083-970 Campinas, Sao Paulo (Brazil); Koehlinger, John [Energy Consultant. 1322 Hepburn Ave 1, Louisville, KY 40204 (United States); Garzone, Pietro; Cornacchia, Giacinto [ENEA Trisaia Research Centre. Prot-STP. SS106 Jonica, Rotondella (Italy)

2008-06-15

This paper examines the history, methods, costs, and future prospects of Cuba's attempts to develop the energy potential of sugarcane. An overview of the main factors affecting the current sugarcane agro-industry in Cuba is provided, along with an analysis of why, despite attempts by the Cuban government to revive the country's sugarcane agro-industry, the industry continues to decline. The prevailing conditions and degree of modernization in Cuban sugar factories are evaluated. The sugar-agro industry's main production bottlenecks are studied. The fall in sugarcane yield from 57.5 ton/ha in 1991 to 22.4 ton/ha in 2005 and its relation to land use is explained. The socio-economic impact of the sugarcane agro-industry's downsizing is assessed. The governmental and quasi-governmental entities in charge of sugarcane energy use development and the country's legal framework are analyzed. The Cuban sugarcane agro-industry's opportunities in the growing international biofuels and bioenergy market are evaluated. To situate Cuba within the global bioenergy market, international best practices relating to the production and commercialization of biofuels are examined to determine the degree to which these experiences can be transferred to Cuba. The analysis of the Cuba sugar industry's biofuel potential is based on a comparative technical-economic assessment of three possible production scenarios: (1) the current situation, where only sugar is produced; (2) simultaneous production of sugar-anhydrous ethanol; and (3) production of sugar-ethanol and simultaneous generation of surplus electricity exported to a public grid. Some of the key assumptions underlying these analyses are as follows: Ethanol production and operation costs for a 7000 ton/day-sugar mill are estimated to be 0.25 and 0.23 USD/l, respectively. The influence of gasoline prices on sugar-ethanol production is also assessed. The kWh production and operation costs starting from

Sugarcane energy use: The Cuban case

International Nuclear Information System (INIS)

Alonso-Pippo, Walfrido; Luengo, Carlos A.; Koehlinger, John; Garzone, Pietro; Cornacchia, Giacinto

2008-01-01

This paper examines the history, methods, costs, and future prospects of Cuba's attempts to develop the energy potential of sugarcane. An overview of the main factors affecting the current sugarcane agro-industry in Cuba is provided, along with an analysis of why, despite attempts by the Cuban government to revive the country's sugarcane agro-industry, the industry continues to decline. The prevailing conditions and degree of modernization in Cuban sugar factories are evaluated. The sugar-agro industry's main production bottlenecks are studied. The fall in sugarcane yield from 57.5 ton/ha in 1991 to 22.4 ton/ha in 2005 and its relation to land use is explained. The socio-economic impact of the sugarcane agro-industry's downsizing is assessed. The governmental and quasi-governmental entities in charge of sugarcane energy use development and the country's legal framework are analyzed. The Cuban sugarcane agro-industry's opportunities in the growing international biofuels and bioenergy market are evaluated. To situate Cuba within the global bioenergy market, international best practices relating to the production and commercialization of biofuels are examined to determine the degree to which these experiences can be transferred to Cuba. The analysis of the Cuba sugar industry's biofuel potential is based on a comparative technical-economic assessment of three possible production scenarios: (1) the current situation, where only sugar is produced; (2) simultaneous production of sugar-anhydrous ethanol; and (3) production of sugar-ethanol and simultaneous generation of surplus electricity exported to a public grid. Some of the key assumptions underlying these analyses are as follows: Ethanol production and operation costs for a 7000 ton/day-sugar mill are estimated to be 0.25 and 0.23 USD/l, respectively. The influence of gasoline prices on sugar-ethanol production is also assessed. The kWh production and operation costs starting from sugarcane bagasse are estimated at 0

Voyager Saturnian ring measurements and the early history of the solar system

International Nuclear Information System (INIS)

Alfven, H.; Axnaes, I.; Brenning, N.; Lindqvist, P.A.

1986-01-01

The mass distribution in the Saturnian ring system is investigated and compared with predictions from the plasma cosmogony. According to this theory, the matter in the rings has once been in the form of a magnetized plasma, in which the gravitation is balanced partly by the centrifugal force and partly by the electromagnetic forces. As the plasma is neutralized, the electromagnetic forces disappear and the matter can be shown to fall in to 2/3 of the original saturnocentric distance. This causes the so called ''cosmogonic shadow effect'', which has been demonstrated earlier for the asteroidal belt and in the large scale structure of the Saturnian ring system. The relevance of the cosmogonic shadow effect is investigated for parts of the Saturnian ring system. It is shown that many structures of the present ring system can be understood as shadows and antishadows of cosmogonic origin. These appear in the form of double rings centered around a position a factor 0.64(slightly less than 2/3) closer to Saturn than the causing feature. Voyager data agree with an accuracy better than 1%. (author)

A ring transducer system for medical ultrasound research.

Science.gov (United States)

Waag, Robert C; Fedewa, Russell J

2006-10-01

An ultrasonic ring transducer system has been developed for experimental studies of scattering and imaging. The transducer consists of 2048 rectangular elements with a 2.5-MHz center frequency, a 67% -6 dB bandwidth, and a 0.23-mm pitch arranged in a 150-mm-diameter ring with a 25-mm elevation. At the center frequency, the element size is 0.30lambda x 42lambda and the pitch is 0.38lambda. The system has 128 parallel transmit channels, 16 parallel receive channels, a 2048:128 transmit multiplexer, a 2048:16 receive multiplexer, independently programmable transmit waveforms with 8-bit resolution, and receive amplifiers with time variable gain independently programmable over a 40-dB range. Receive signals are sampled at 20 MHz with 12-bit resolution. Arbitrary transmit and receive apertures can be synthesized. Calibration software minimizes system nonidealities caused by noncircularity of the ring and element-to-element response differences. Application software enables the system to be used by specification of high-level parameters in control files from which low-level hardware-dependent parameters are derived by specialized code. Use of the system is illustrated by producing focused and steered beams, synthesizing a spatially limited plane wave, measuring angular scattering, and forming b-scan images.

A progress report on the g-2 storage ring magnet system

International Nuclear Information System (INIS)

Bunce, G.; Cullen, J.; Danby, G.

1995-01-01

The 3.1 GeV muon storage ring for the g-2 experiment at Brookhaven National Laboratory hat three large solenoid magnets that form a continuous 1.451 tesla storage ring dipole with an average beam bond radius of 7.1 metors. In addition to the three storage ring solenoids, there is an inflector dipole with nested dipole coils that create very little stray magnetic field. A superconducting shield on the infractor gets rid of most of the remaining stray flux. This paper reports on the progress made on the storage ring solenoid magnet system and the inflector as of June 1995. The results of cryogenic system tests are briefly reported

31 CFR 515.549 - Bank accounts and other property of non-Cuban citizens who were in Cuba on or after July 8, 1963.

Science.gov (United States)

2010-07-01

... non-Cuban citizens who were in Cuba on or after July 8, 1963. 515.549 Section 515.549 Money and... Licensing Policy § 515.549 Bank accounts and other property of non-Cuban citizens who were in Cuba on or... accounts and other property of non-Cuban citizens who have left Cuba, provided that they submit evidence...

Beam position monitor system for storage rings

International Nuclear Information System (INIS)

Nakamura, M.; Hinkson, J.A.

1985-05-01

Beam position monitors (BPM) for synchrotron light storage rings usually consist of beam pickup electrodes, coaxial relays and a narrowband receiver. While accurate, these systems are slow and of limited use in the commissioning of an accelerator. A beam position monitor is described which is intended to be a principal diagnostic during debug and routine running of a storage ring. It is capable of measuring the position of a single bunch on the first or nth orbit to an accuracy of a few percent. Stored beam position is more accurately measured with averaging techniques. Beam position changes can be studied in a bandwidth from DC to a few MHz. The beam monitor electronics consist of a separate amplification, detection, and sampling channel for each beam pickup electrode. Fast switches in each channel permit selection of the nth turn for measurement (single bunch mode). A calibration pulse is injected into each channel after beam measurement to permit gain offsets to be measured and removed from the final data. While initially more costly than the usual beam position monitor system, this sytem will pay for itself in reduced storage ring debug and trouble shooting time. 5 refs., 5 figs

Single-pass BPM system of the Photon Factory storage ring.

Science.gov (United States)

Honda, T; Katoh, M; Mitsuhashi, T; Ueda, A; Tadano, M; Kobayashi, Y

1998-05-01

At the 2.5 GeV ring of the Photon Factory, a single-pass beam-position monitor (BPM) system is being prepared for the storage ring and the beam transport line. In the storage ring, the injected beam position during the first several turns can be measured with a single injection pulse. The BPM system has an adequate performance, useful for the commissioning of the new low-emittance lattice. Several stripline BPMs are being installed in the beam transport line. The continuous monitoring of the orbit in the beam transport line will be useful for the stabilization of the injection energy as well as the injection beam orbit.

What is the Role of the Cuban Revolutionary Armed Forces (FAR) in a Post-Castro Cuba? What Role will the U.S. Military Play

Science.gov (United States)

1993-04-01

through his brother Raul for the past 30 years. The Spanish heritage and machismo tradition of the Cuban male is strong: the long struggle the Cubans...himself on the air in an attempt to change the course of Cuban history. " (Oppenheimer 132). None of this machismo tradition has been lost on Fidel Castro

Real time global orbit feedback system for NSLS x-ray ring

International Nuclear Information System (INIS)

Yu, L.H.; Biscardi, R.; Bittner, J.; Fauchet, A.M.; Krinsky, F.S.; Nawrocky, R.J.; Rothman, J.; Singh, O.V.; Yang, K.M.

1991-01-01

We report on the design and commissioning of a real time harmonic global orbit feedback system for the NSLS X-ray ring. This system uses 8 pick-up electrode position monitors and 16 trim dipole magnets to eliminate 3 harmonic components of the orbit fluctuations. Because of the larger number of position monitors and trim magnets, the X-ray ring feedback system differs from the previously reported VUV ring system in that the Fourier analysis and harmonic generation networks are comprised of MDAC boards controlled by computer. The implementation of the global feedback system has resulted in a dramatic improvement of orbit stability, by more than a factor of five everywhere. Simultaneous operation of the global and several local bump feedback systems has been achieved. 4 refs., 5 figs

Ring resonator systems to perform optical communication enhancement using soliton

CERN Document Server

Amiri, Iraj Sadegh

2014-01-01

The title explain new technique of secured and high capacity optical communication signals generation by using the micro and nano ring resonators. The pulses are known as soliton pulses which are more secured due to having the properties of chaotic and dark soliton signals with ultra short bandwidth. They have high capacity due to the fact that ring resonators are able to generate pulses in the form of solitons in multiples and train form. These pulses generated by ring resonators are suitable in optical communication due to use the compact and integrated rings system, easy to control, flexibi

Development of an Acoustic Levitation Linear Transportation System Based on a Ring-Type Structure.

Science.gov (United States)

Thomas, Gilles P L; Andrade, Marco A B; Adamowski, Julio Cezar; Silva, Emilio Carlos Nelli

2017-05-01

A linear acoustic levitation transportation system based on a ring-type vibrator is presented. The system is composed by two 21-kHz Langevin transducers connected to a ring-shaped structure formed by two semicircular sections and two flat plates. In this system, a flexural standing wave is generated along the ring structure, producing an acoustic standing wave between the vibrating ring and a plane reflector located at a distance of approximately a half wavelength from the ring. The acoustic standing wave in air has a series of pressure nodes, where small particles can be levitated and transported. The ring-type transportation system was designed and analyzed by using the finite element method. Additionally, a prototype was built and the acoustic levitation and transport of a small polystyrene particle was demonstrated.

Morphological measurements and body indices for Cuban Creole goats and their crossbreds

Directory of Open Access Journals (Sweden)

Edilberto Chacón

2011-08-01

Full Text Available In this work, linear body measures were taken and production indices calculated for 100 Cuban Creole goats and 100 crossbred goats in order to aid in the characterization of animal genetic resources in Cuba. Low variation was found for all indices of the Creole goats, showing homogeneity between the groups of animals studied. Most of the functional indices are related to the milk biotype which is in agreement the possible origin of the breed from animals of the Iberian Peninsula and Canary Islands. The crossbreds were more varied, mostly due to undesigned disorganized crossing. These data may help in identifying a commercial niche for the breed and contribute to in situ conservation of the Cuban Creole goat.

Dragging of inertial frames in the composed black-hole-ring system

International Nuclear Information System (INIS)

Hod, Shahar

2015-01-01

A well-established phenomenon in general relativity is the dragging of inertial frames by a spinning object. In particular, due to the dragging of inertial frames by a ring orbiting a central black hole, the angular velocity Ω H BH-ring of the black-hole horizon in the composed black-hole-ring system is no longer related to the black-hole angular momentum J H by the simple Kerr-like (vacuum) relation Ω H Kerr (J H ) = J H /2M 2 R H (here M and R H are the mass and horizon-radius of the black hole, respectively). Will has performed a perturbative treatment of the composed black-hole-ring system in the regime of slowly rotating black holes and found the explicit relation Ω H BH-ring (J H = 0, J R , R) = 2J R /R 3 for the angular velocity of a central black hole with zero angular momentum, where J R and R are respectively the angular momentum of the orbiting ring and its proper circumferential radius. Analyzing a sequence of black-hole-ring configurations with adiabatically varying (decreasing) circumferential radii, we show that the expression found by Will for Ω H BH-ring (J H = 0, J R , R) implies a smooth transition of the central black-hole angular velocity from its asymptotic near-horizon value Ω H BH-ring (J H = 0, J R , R → R H + ) → 2J R /R H 3 (that is, just before the assimilation of the ring by the central black hole), to its final Kerr (vacuum) value Ω H Kerr (J H new )= J H new /2M new2 R H new [that is, after the adiabatic assimilation of the ring by the central black hole. Here J H new = J R , M new , and R H new are the new parameters of the resulting Kerr (vacuum) black hole after it assimilated the orbiting ring]. We use this important observation in order to generalize the result of Will to the regime of black-hole-ring configurations in which the central black holes possess non-zero angular momenta. In particular, it is shown that the continuity argument (namely, the characteristic smooth evolution of the black-hole angular velocity

Structure and magnetic field of periodic permanent magnetic focusing system with open magnetic rings

International Nuclear Information System (INIS)

Peng Long; Li Lezhong; Yang Dingyu; Zhu Xinghua; Li Yuanxun

2011-01-01

The magnetic field along the central axis for an axially magnetized permanent magnetic ring was investigated by analytical and finite element methods. For open magnetic rings, both calculated and measured results show that the existence of the radial magnetic field creates a remarkable cosine distribution field along the central axis. A new structure of periodic permanent magnet focusing system with open magnetic rings is proposed. The structure provides a satisfactory magnetic field with a stable peak value of 120 mT for a traveling wave tube system. - Research highlights: → For open magnetic rings, both calculated and measured results show that the existence of the radial magnetic field creates a remarkable cosine distribution field along the central axis. → A new structure of periodic permanent magnet (PPM) focusing system with open magnetic rings is proposed. → The new PPM focusing system with open magnetic rings meets the requirements for TWT system.

The vacuum interlock system for the CELSIUS ring

International Nuclear Information System (INIS)

Gajewski, K.

1990-01-01

A vacuum interlock system has been designed and built for the CELSIUS storage ring. The ultrahigh-vacuum system of CELSIUS has a design pressure of 10 -11 mbar. This is achieved by using vacuum-fired stainless-steel chambers, baking the whole ring to 300degC and running some 50 sputter ion and titanium sublimation pumps. The turbopumps, combined with roughing pumps, are used during the pump-down and the bake-out. The pressure is monitored by Penning vacuum gauges. There is a number of programmable pressure thresholds set to trigger various events (like closing the sector valves, disabling the bake-out, etc.). The interlock system is based on the Mitsubishi programmable logic controller (PLC). An IBM PC is used as an operator's console. The operation and performance of the system is described. On the basis of present experience an upgrading of the system is suggested. (orig.)

1rst Congress of the Cuban Society of Soil Sciences

International Nuclear Information System (INIS)

1988-01-01

Abstracts from different works presented at the 1st Congress of the Cuban Society of Soil Sciences (Havana, December 1988) are contained in this book. Works have been performed on soil genesis, classification and cartography; soil erosion, conservation and improvement; agrochemicstry; soil physics and technology, and biology of soils

Model calibration and beam control systems for storage rings

International Nuclear Information System (INIS)

Corbett, W.J.; Lee, M.J.; Ziemann, V.

1993-04-01

Electron beam storage rings and linear accelerators are rapidly gaining worldwide popularity as scientific devices for the production of high-brightness synchrotron radiation. Today, everybody agrees that there is a premium on calibrating the storage ring model and determining errors in the machine as soon as possible after the beam is injected. In addition, the accurate optics model enables machine operators to predictably adjust key performance parameters, and allows reliable identification of new errors that occur during operation of the machine. Since the need for model calibration and beam control systems is common to all storage rings, software packages should be made that are portable between different machines. In this paper, we report on work directed toward achieving in-situ calibration of the optics model, detection of alignment errors, and orbit control techniques, with an emphasis on developing a portable system incorporating these tools

The Abort Kicker System for the PEP-II Storage Rings at SLAC

International Nuclear Information System (INIS)

Delamare, Jeffrey E

2003-01-01

The PEP-II project has two storage rings. The HER (High Energy Ring) has up to 1.48 A of election beam at 9 GeV, and the LER (Low Energy Ring) has up to 2.14 A of positron beam at 3.1 GeV. To protect the HER and LER beam lines in the event of a ring component failure, each ring has an abort kicker system which directs the beam into a dump when a failure is detected. Due to the high current of the beams, the beam kick is tapered from 100% to 80% in 7.33 (micro)S (the beam transit time around the ring). This taper distributes the energy evenly across the window which separates the ring from the beam dump such that the window is not damaged. The abort kicker trigger is synchronized with the ion clearing gap of the beam allowing for the kicker field to rise from 0-80% while there is no beam in the kicker magnet. Originally the kicker system was designed for a rise time of 370nS [1], but because the ion clearing gap was reduced in half, so was the rise time requirement for the kicker. This report discusses the design of the system interlocks, diagnostics, and modulator with the modifications necessary to accommodate an ion clearing gap of 185nS

A Saturn Ring Observer Mission Using Multi-Mission Radioisotope Power Systems

International Nuclear Information System (INIS)

Abelson, Robert D.; Spilker, Thomas R.; Shirley, James H.

2006-01-01

Saturn remains one of the most fascinating planets within the solar system. To better understand the complex ring structure of this planet, a conceptual Saturn Ring Observer (SRO) mission is presented that would spend one year in close proximity to Saturn's A and B rings, and perform detailed observations and measurements of the ring particles and electric and magnetic fields. The primary objective of the mission would be to understand ring dynamics, including the microphysics of individual particles and small scale (meters to a few kilometers) phenomena such as particle agglomeration behavior. This would be accomplished by multispectral imaging of the rings at multiple key locations within the A and B rings, and by ring-particle imaging at an unprecedented resolution of 0.5 cm/pixel. The SRO spacecraft would use a Venus-Earth-Earth-Jupiter Gravity Assist (VEEJGA) and be aerocaptured into Saturn orbit using an advanced aeroshell design to minimize propellant mass. Once in orbit, the SRO would stand off from the ring plane 1 to 1.4 km using chemical thrusters to provide short propulsive maneuvers four times per revolution, effectively causing the SRO vehicle to 'hop' above the ring plane. The conceptual SRO spacecraft would be enabled by the use of a new generation of multi-mission Radioisotope Power Systems (RPSs) currently being developed by NASA and DOE. These RPSs include the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) and Stirling Radioisotope Generator (SRG). The RPSs would generate all necessary electrical power (≥330 We at beginning of life) during the 10-year cruise and 1-year science mission (∼11 years total). The RPS heat would be used to maintain the vehicle's operating and survival temperatures, minimizing the need for electrical heaters. Such a mission could potentially launch in the 2015-2020 timeframe, with operations at Saturn commencing in approximately 2030

Cuban Voices: A Case Study of English Language Teacher Education

Science.gov (United States)

Smith, Steven John

2016-01-01

This case study uses qualitative research methods and a postcolonial paradigm to listen to the voices of Cuban teacher educators describing how they educate and prepare English language teachers in Cuba. English language teacher education in Cuba includes features that are considered innovative, contemporary and good practice in the Western world.…

Vortex rings in classical and quantum systems

International Nuclear Information System (INIS)

Barenghi, C F; Donnelly, R J

2009-01-01

The study of vortex rings has been pursued for decades and is a particularly difficult subject. However, the discovery of quantized vortex rings in superfluid helium has greatly increased interest in vortex rings with very thin cores. While rapid progress has been made in the simulation of quantized vortex rings, there has not been comparable progress in laboratory studies of vortex rings in a viscous fluid such as water. This article overviews the history and current frontiers of classical and quantum vortex rings. After introducing the classical results, this review discusses thin-cored vortex rings in superfluid helium in section 2, and recent progress in understanding vortex rings of very thin cores propagating in water in section 3. (invited paper)

Dynamical Evolution of Ring-Satellite Systems

Science.gov (United States)

Ohtsuki, Keiji

2005-01-01

The goal of this research was to understand dynamical processes related to the evolution of size distribution of particles in planetary rings and application of theoretical results to explain features in the present rings of giant planets. We studied velocity evolution and accretion rates of ring particles in the Roche zone. We developed a new numerical code for the evolution of ring particle size distribution, which takes into account the above results for particle velocity evolution and accretion rates. We also studied radial diffusion rate of ring particles due to inelastic collisions and gravitational encounters. Many of these results can be also applied to dynamical evolution of a planetesimal disk. Finally, we studied rotation rates of moonlets and particles in planetary rings, which would influence the accretional evolution of these bodies. We describe our key accomplishments during the past three years in more detail in the following.

Dragging of inertial frames in the composed black-hole-ring system

Energy Technology Data Exchange (ETDEWEB)

Hod, Shahar [The Ruppin Academic Center, Emeq Hefer (Israel); The Hadassah Institute, Jerusalem (Israel)

2015-11-15

A well-established phenomenon in general relativity is the dragging of inertial frames by a spinning object. In particular, due to the dragging of inertial frames by a ring orbiting a central black hole, the angular velocity Ω{sub H}{sup BH-ring} of the black-hole horizon in the composed black-hole-ring system is no longer related to the black-hole angular momentum J{sub H} by the simple Kerr-like (vacuum) relation Ω{sub H}{sup Kerr}(J{sub H}) = J{sub H}/2M{sup 2}R{sub H} (here M and R{sub H} are the mass and horizon-radius of the black hole, respectively). Will has performed a perturbative treatment of the composed black-hole-ring system in the regime of slowly rotating black holes and found the explicit relation Ω{sub H}{sup BH-ring}(J{sub H} = 0, J{sub R}, R) = 2J{sub R}/R{sup 3} for the angular velocity of a central black hole with zero angular momentum, where J{sub R} and R are respectively the angular momentum of the orbiting ring and its proper circumferential radius. Analyzing a sequence of black-hole-ring configurations with adiabatically varying (decreasing) circumferential radii, we show that the expression found by Will for Ω{sub H}{sup BH-ring}(J{sub H} = 0, J{sub R}, R) implies a smooth transition of the central black-hole angular velocity from its asymptotic near-horizon value Ω{sub H}{sup BH-ring}(J{sub H} = 0, J{sub R}, R → R{sub H}{sup +}) → 2J{sub R}/R{sub H}{sup 3} (that is, just before the assimilation of the ring by the central black hole), to its final Kerr (vacuum) value Ω{sub H}{sup Kerr}(J{sub H}{sup new})= J{sub H}{sup new}/2M{sup new2}R{sub H}{sup new} [that is, after the adiabatic assimilation of the ring by the central black hole. Here J{sub H}{sup new} = J{sub R}, M{sup new}, and R{sub H}{sup new} are the new parameters of the resulting Kerr (vacuum) black hole after it assimilated the orbiting ring]. We use this important observation in order to generalize the result of Will to the regime of black-hole-ring configurations

Dragging of inertial frames in the composed black-hole–ring system

Energy Technology Data Exchange (ETDEWEB)

Hod, Shahar, E-mail: shaharhod@gmail.com [The Ruppin Academic Center, 40250, Emeq Hefer (Israel); The Hadassah Institute, 91010, Jerusalem (Israel)

2015-11-19

A well-established phenomenon in general relativity is the dragging of inertial frames by a spinning object. In particular, due to the dragging of inertial frames by a ring orbiting a central black hole, the angular velocity Ω{sub H}{sup BH-ring} of the black-hole horizon in the composed black-hole–ring system is no longer related to the black-hole angular momentum J{sub H} by the simple Kerr-like (vacuum) relation Ω{sub H}{sup Kerr}(J{sub H})=J{sub H}/2M{sup 2}R{sub H} (here M and R{sub H} are the mass and horizon-radius of the black hole, respectively). Will has performed a perturbative treatment of the composed black-hole–ring system in the regime of slowly rotating black holes and found the explicit relation Ω{sub H}{sup BH-ring}(J{sub H}=0,J{sub R},R)=2J{sub R}/R{sup 3} for the angular velocity of a central black hole with zero angular momentum, where J{sub R} and R are respectively the angular momentum of the orbiting ring and its proper circumferential radius. Analyzing a sequence of black-hole–ring configurations with adiabatically varying (decreasing) circumferential radii, we show that the expression found by Will for Ω{sub H}{sup BH-ring}(J{sub H}=0,J{sub R},R) implies a smooth transition of the central black-hole angular velocity from its asymptotic near-horizon value Ω{sub H}{sup BH-ring}(J{sub H}=0,J{sub R},R→R{sub H}{sup +})→2J{sub R}/R{sub H}{sup 3} (that is, just before the assimilation of the ring by the central black hole), to its final Kerr (vacuum) value Ω{sub H}{sup Kerr}(J{sub H}{sup new})=J{sub H}{sup new}/2M{sup new2}R{sub H}{sup new} [that is, after the adiabatic assimilation of the ring by the central black hole. Here J{sub H}{sup new}=J{sub R}, M{sup new}, and R{sub H}{sup new} are the new parameters of the resulting Kerr (vacuum) black hole after it assimilated the orbiting ring]. We use this important observation in order to generalize the result of Will to the regime of black-hole–ring configurations in which the

Each Sheep with Its Mate: Marking Race and Legitimacy in Cuban Catholic Parish Archives, 1890-1940

Directory of Open Access Journals (Sweden)

Enid Lynette Logan

2010-07-01

Full Text Available Examines the politics of racialization in Cuba from the period after full emancipation to the restrictive immigration policy of the 1930s, through an analysis of the record-keeping practices of the Cuban Catholic Church. The study uses baptismal and marital records to record information on the intimate, racialized, and gendered domains of Cuban social life. Author points out that certain policies adopted by religious authoritites gestured towards inclusivism and egalitarianism, others served to reinforce hierarchies based upon race and rank.

A pilot investigation to constrain the presence of ring systems around transiting exoplanets

Science.gov (United States)

Hatchett, W. Timothy; Barnes, Jason W.; Ahlers, John P.; MacKenzie, Shannon M.; Hedman, Matthew M.

2018-04-01

We demonstrate a process by which to evaluate the presence of large, Saturn-like ring systems around transiting extrasolar giant planets. We use extrasolar planet candidate KOI-422.01 as an example around which to establish limits on the presence of ring systems. We find that the spherical-planet (no-rings) fit matches the lightcurve of KOI-422.01 better than a lightcurve with a planet having obliquity angles 90°, 60°, 45°, or 20°. Hence we find no evidence for rings around KOI-422.01, but the methods that we have developed can be used for more comprehensive ring searches in the future. If the Hedman (2015) low-temperature rings hypothesis is correct, then the first positive detection of exorings might require transits of very long period ( ≳ 10 yr) giant planets outside their stars' ice lines.

Numerical simulation study on new RF system of Hefei storage ring

International Nuclear Information System (INIS)

Xu Hongliang; Wang Lin; Huang Guirong; Zhang Pengfei; Li Weimin; Liu Zuping; He Duohui

2005-01-01

The two injection ways of new RF system of Hefei storage ring were discussed. In the process of both large detuning injection and tuning injection, the variation of tuning angle and visual detuning angle with beam current intensity was analyzed. The calculation results show that the two injection ways are manipulable for new RF system in phase II project of Hefei storage ring. (author)

Creating a safety culture in the regulatory authority: The Cuban experience

International Nuclear Information System (INIS)

Ferro Fernandez, R.; Guillen Campos, A.

2002-01-01

The Cuban regulatory authority has been working during several years for the fostering and development of a high Safety Culture level in nuclear activities in the country. As starting point to achieve this objective the assessment of the Safety Culture level in the regulatory authority performance was considered an important issue. For this purpose a preliminary diagnosis was carried out by means of a national survey that allowed identifying some areas of the regulatory activity that required improvements in order to achieve a higher Safety Culture and to immediately implement appropriate actions. Two of the most important actions undertaken were: the statement of the regulatory authority Safety Policy which governs and determines the performance of this organization and its staff and also the implementation of a new interaction practice at top level between the regulatory authority and the utilities of the nuclear sector through the Annual Regulatory Conference. The present paper summarizes these two introduced practices into the Cuban regulatory activity. (author)

soirées Rock - Cuban salsa, bachata and Kizomba workshops

CERN Multimedia

CERN Dancing Club

2015-01-01

The CERN Dancing Club organizes a Cuban salsa, bachata and Kizomba workshop open to everyone on Saturday 9 May in its B566 ballroom (See the poster). Furthermore, the club invites you to its Rock party. Club parties are free and open to everyone. You bring something to eat and the club offers the drinks (non alcoholic)    

Application of cubane-type structures to hydro-treatment catalysis; Application des structures d'architecture cubane a la catalyse d'hydrotraitement

Energy Technology Data Exchange (ETDEWEB)

Marchand, K.

2003-11-01

[Mo{sub 3}S{sub 4}(H{sub 2}O){sub 9}]{sup 4+} has been prepared and supported on zeolites H-USY and NaY. Using this cluster as a precursor for HDT catalysts has many advantages: it is cationic, already in a sulfided form, and a promoter such as a second metal M' such as Cu, Ni or Pd can be incorporated to form Mo{sub 3}M'S{sub 4}{sup 4+}. The cubane structure was found unchanged after loading in the case of NaY (EXAFS, XPS) and although TEM showed that Mo was mainly on the outer surface of the zeolite crystals, DRX confirmed that a modification of the counter ion also occurred, and an isotherm was obtained with NaY zeolite. A thermal stability study was led under N{sub 2} and a mixture of H{sub 2}/H{sub 2}S to optimize the pretreatment of the catalysts. Those were subsequently pre-sulfided and tested in toluene hydrogenation and their activities with both types of zeolites turned out to be the same or even better than that of catalysts prepared by the classical route. An application to mixed cubane-type structures is also reported. (author)

Proton storage ring (PSR) diagnostics and control system

International Nuclear Information System (INIS)

Clout, P.

1983-01-01

When any new accelerator or storage ring is built that advances the state of the art, the diagnostic system becomes extremely important in tuning the facility to full specification. This paper will discuss the various diagnostic devices planned or under construction for the PSR and their connection into the control system

Design for ANL 7 GeV storage ring vacuum system

International Nuclear Information System (INIS)

Wehrle, R.B.; Nielsen, R.W.

1988-01-01

The 7-GeV Advanced Photon Source (APS) design includes a storage ring having a 1060-m circumference with the capability of accommodating 34 insertion devices (ID) and their associated photon beam lines. An additional 35 photon lines can be provided from bending magnets. The vacuum system for the storage ring is designed to maintain a beam-on operating pressure of 1n Torr or less to achieve a positron beam lifetime of approximately 20 hours. The vacuum system and it's current developmental status are described

Present scenery of cuban legislation in the field of legal verification of dosimetric instruments used in radiological protection

International Nuclear Information System (INIS)

Salas G, Walwyn; Morales Monzon, J.A.; Hernandez Blanche, E.

2001-01-01

The main objective of legal metrology is to ensure the public guaranty from the point of view of safety, and the suitable accuracy of the measurements that are made on health, environmental applications, and trade. The International Organization of Legal Metrology included the ionizing radiation field on those for which the use of the verified measuring instruments are suggested. . The paper presents the advances of Cuban legislation in this field, promoted by issue of the Decree-Law 183 of Metrology. As part of such advances, the Cuban standards for verification NC 44:1999 'X and Gamma Radiation Measuring Instruments. Verification methods' is discussed. This standard was elaborated in the Cuban Secondary Standard Dosimetry Laboratory, and it is based on the available relevant international standards. Results from verification service during the year 2000 are also provided.(author)

The Abort Kicker System for the PEP-II Storage Rings at SLAC.

CERN Document Server

Delamare, J E

2003-01-01

The PEP-II project has two storage rings. The HER (High Energy Ring) has up to 1.48 A of election beam at 9 GeV, and the LER (Low Energy Ring) has up to 2.14 A of positron beam at 3.1 GeV. To protect the HER and LER beam lines in the event of a ring component failure, each ring has an abort kicker system which directs the beam into a dump when a failure is detected. Due to the high current of the beams, the beam kick is tapered from 100% to 80% in 7.33 (micro)S (the beam transit time around the ring). This taper distributes the energy evenly across the window which separates the ring from the beam dump such that the window is not damaged. The abort kicker trigger is synchronized with the ion clearing gap of the beam allowing for the kicker field to rise from 0-80% while there is no beam in the kicker magnet. Originally the kicker system was designed for a rise time of 370nS [1], but because the ion clearing gap was reduced in half, so was the rise time requirement for the kicker. This report discusses the des...

The g-2 storage ring superconducting magnet system

International Nuclear Information System (INIS)

Green, M.A.

1993-09-01

The g-2 μ lepton (muon) storage ring is a single dipole magnet that is 44 meters in circumference. The storage ring dipole field is created by three large superconducting solenoid coils. A single outer solenoid, 15.1 meters in diameter, carries 254 kA. Two inner solenoids, 13.4 meters in diameter, carry 127 kA each in opposition to the current carried by the outer solenoid. A room temperature C shaped iron yoke returns the magnetic flux and shapes the magnetic field in a 180 mm gap where the stored muon beam circulates. The gap induction will be 1.47 T. This report describes the three large superconducting solenoids, the cryogenic system needed to keep them cold, the solenoid power supply and the magnet quench protection system

Evaluation and distribution of doses received by Cuban population due to environmental sources of radioactivity

International Nuclear Information System (INIS)

Zerquera, Juan T.; Prendes Alonso, Miguel; Fernandez Gomez, Isis M.; Lopez Bejerano, Gladys

2008-01-01

Full text: In the frame of a national research project supported by the Nuclear Energy Agency of the Ministry of Science, Technology and Environment of the Republic of Cuba doses received by Cuban population due to the exposure to existing in the environment sources of radiation were assessed. Direct measurements of sources representing 90% of average total doses to world population according to UNSCEAR data were made and estimations of doses were obtained for the different components of the total dose: doses due to the exposure to cosmic radiation, external terrestrial radiation, potassium contained in human body and inhalation and ingestion of radionuclides present in the environment. Using the obtained results it was made an estimation of total doses to Cuban population due to environmental radiation sources and the contributions of different dose components were assessed. This was carried out through a Monte Carlo simulation of the total doses using the parameter of dose distributions obtained for the different contributors (components) to total dose. On the basis of the estimations the average total effective dose to Cuban population due to the exposure to environmental sources was estimated as 1.1 ± 0.3 mSv per year. This low dose value is in the range of doses estimated by UNSCEAR for world population due to natural background and can be explained by the specific of Cuban environment: a majority of the population living at the sea level or at low altitudes, relative low content of primordial radionuclides in soils and high ventilation rates in dwellings. All the instructions specified in the Call for Abstracts should be taken into account. e/ 41 and 457. (author)

Acute liver failure in Cuban children.

Science.gov (United States)

Silverio, César E; Smithen-Romany, Chleo Y; Hondal, Norma I; Díaz, Hetzel O; Castellanos, Marlen I; Sosa, Oramis

2015-01-01

Acute liver failure is rare in pediatric patients and is one of the most challenging medical emergencies due to its prognostic and therapeutic implications. The best scientific evidence worldwide comes from multicenter studies in developed countries. In Cuba, there are no prior studies of this disorder in children. Describe the main clinical features of Cuban children treated at a national referral center for acute liver failure, as defined by recognized diagnostic criteria for pediatric patients. A case series study was conducted comprising patients diagnosed with acute liver failure treated from 2005 to 2011 in the hepatology and liver transplant service at Havana's William Soler University Children's Hospital. Variables were age group, etiology of acute liver failure, grade of hepatic encephalopathy, blood chemistry variables, and clinical outcome (whether or not spontaneous recovery of liver function occurred). Associations between variables were assessed using contingency tables, and case fatality was calculated, as well as relative risk with its 95% confidence interval. The Mann-Whitney U test was used to compare means of laboratory test results. Median age of the 31 patients studied (14 boys and 17 girls) was 24 months (range 1-180). Time between symptom onset and diagnosis of acute liver failure was 25.1 days (SD 16.8). Infection was the most common etiology, present in 61.3% of cases (19/31); nonhepatotropic viruses, especially cytomegalovirus, predominated in infants. Spontaneous recovery occurred in 15 patients (48.4%), 3 (9.7%) received transplants, and 13 died, for a case fatality of 41.9%. Outcome was not associated with etiology (p = 0.106), but was statistically associated with degree of hepatic encephalopathy (p failure in Cuban children calls for further epidemiologic study and identification of local underlying determinants of this phenomenon.

Final results of the Cuban program for children from areas affected by the Chernobyl accident

International Nuclear Information System (INIS)

Medina, Julio; García, Omar

2016-01-01

From 1990 till 2011, a free health care program for children from areas affected by the Chernobyl accident was organized and implemented by the Cuban Government. A significant number of qualified personal in medicine and science collaborated with this program. The information gathered for more than 21 years and the conclusive results obtained in the program are presented here. During this time, 26 114 patients, 84 % children, mostly from Ukraine, Russia and Belarus were treated in the mentioned program. Other aspects of the Cuban medical assistance in Ukraine and the main results obtained in the radiological impact evaluation of the accident on the children treated in Cuba are also included. (author)

Storage Rings

International Nuclear Information System (INIS)

Fischer, W.

2010-01-01

Storage rings are circular machines that store particle beams at a constant energy. Beams are stored in rings without acceleration for a number of reasons (Tab. 1). Storage rings are used in high-energy, nuclear, atomic, and molecular physics, as well as for experiments in chemistry, material and life sciences. Parameters for storage rings such as particle species, energy, beam intensity, beam size, and store time vary widely depending on the application. The beam must be injected into a storage ring but may not be extracted (Fig. 1). Accelerator rings such as synchrotrons are used as storage rings before and after acceleration. Particles stored in rings include electrons and positrons; muons; protons and anti-protons; neutrons; light and heavy, positive and negative, atomic ions of various charge states; molecular and cluster ions, and neutral polar molecules. Spin polarized beams of electrons, positrons, and protons were stored. The kinetic energy of the stored particles ranges from 10 -6 eV to 3.5 x 10 12 eV (LHC, 7 x 10 12 eV planned), the number of stored particles from one (ESR) to 1015 (ISR). To store beam in rings requires bending (dipoles) and transverse focusing (quadrupoles). Higher order multipoles are used to correct chromatic aberrations, to suppress instabilities, and to compensate for nonlinear field errors of dipoles and quadrupoles. Magnetic multipole functions can be combined in magnets. Beams are stored bunched with radio frequency systems, and unbunched. The magnetic lattice and radio frequency system are designed to ensure the stability of transverse and longitudinal motion. New technologies allow for better storage rings. With strong focusing the beam pipe dimensions became much smaller than previously possible. For a given circumference superconducting magnets make higher energies possible, and superconducting radio frequency systems allow for efficient replenishment of synchrotron radiation losses of large current electron or positron beams

The enthalpy of sublimation of cubane

International Nuclear Information System (INIS)

Bashir-Hashemi, A.; Chickos, James S.; Hanshaw, William; Zhao Hui; Farivar, Behzad S.; Liebman, Joel F.

2004-01-01

The sublimation enthalpy of cubane, a key reference material for force field and quantum mechanical computations, was measured by combining the vaporization enthalpy at T = 298.15 K to the sum of the fusion enthalpy measured at T = 405 K and a solid-solid phase transition that occurs at T 394 K. The fusion and solid-solid phase transitions were measured previously. A sublimation enthalpy value of (55.2 ± 2.0) kJ mol -1 at T = 298.15 K was obtained. This value compares quite favorably the value obtained by comparing the sublimation enthalpy of similar substances as a function of their molar masses but is at odds with earlier measurements

The enthalpy of sublimation of cubane

Energy Technology Data Exchange (ETDEWEB)

Bashir-Hashemi, A.; Chickos, James S.; Hanshaw, William; Zhao Hui; Farivar, Behzad S.; Liebman, Joel F

2004-12-15

The sublimation enthalpy of cubane, a key reference material for force field and quantum mechanical computations, was measured by combining the vaporization enthalpy at T = 298.15 K to the sum of the fusion enthalpy measured at T = 405 K and a solid-solid phase transition that occurs at T 394 K. The fusion and solid-solid phase transitions were measured previously. A sublimation enthalpy value of (55.2 {+-} 2.0) kJ mol{sup -1} at T = 298.15 K was obtained. This value compares quite favorably the value obtained by comparing the sublimation enthalpy of similar substances as a function of their molar masses but is at odds with earlier measurements.

"Nation or death": the Cuban Revolution and the 1990’s crisis.

Directory of Open Access Journals (Sweden)

Julian Araujo Brito

2012-05-01

Full Text Available This article aims to analyze the survival conditions of the cuban political regime from the end of the cold war, during the “Special Period”. The breakdown of the socialist bloc between 1989 and 1991 certainly represented an important change of direction for the Cuban Revolution and generated an economic crisis of great proportions, which put at risk the very permanence of the revolutionary regime. However, it was allowed to survive - despite the diffi cult inner and outer conditions and the frequent contrary predictions – to its most delicate moment since the origin in 1959. Although there was a plan for economic reforms and policies to a lesser extent, the survival of the regime was bounded to its nationalistic appeal, what was the political legitimacy before the socialism crisis, as well as the defense of the social achievements of the 30 years of the revolutionary regime.

Nuclear Magnetic Resonance skull in Cuban families first diagnosed with Friedreich's ataxia

International Nuclear Information System (INIS)

Cruz Marinno, Tania; Alvarez Cuesta, Jose Alberto; Aguilera Rodriguez, Raul; Velazquez Perez, Luis

2011-01-01

Friedreich's ataxia is characterized by age of onset before 25 years, progressive ataxia, dysarthria, absent deep tendon reflexes and impaired vibration sense. This research was conducted in order to describe the imaging features of central nervous system structures in the early Cuban families diagnosed with the disease. A team of 0.23 Tesla-PANORAMA-Phylips Medical Systems, with a standard head coil, axial slices were obtained using 5mm thick FLAIR sequences, T1 and T2, and sagittal T1 and T2 in three individuals with confirmatory molecular diagnosis of Friedreich's ataxia and six healthy controls matched by age and sex. The morphological structures most affected are the cervical spinal cord, cerebellum and pons, which provides in vivo evidence that the disease leads to atrophy of these structures

Requirements to cuban reinforcing steel under seismic demand; Exigencias al acero de refuerzo cubano ante la demanda sismica

Energy Technology Data Exchange (ETDEWEB)

Frometa Salas, Z. P.; Villalonga Vianez, J. A.

2009-07-01

The behaviour of steel manufactured according to the Cuban standard NC 7:02 is studied, in order to evaluate about the conformance to requirements of the seismic design. Steel bars of Grade G-40 and G-60, of all commercial diameters between 10 and 32 mm, were test with this purpose. An experimental program was developed, that include dimensional verifications, tensile testing, ben and rebend, hardness testing and chemical composition tests. The results showed that steel bars satisfy geometric and tensile requirements of Cuban standard, however, some tested samples fulfill the demands that establish some codes about the required ductility to adequate perform of building of reinforced concrete where prevalence the earthquake. Conclusions about the necessity to consider in the future Cuban standard, special requirements to steel that assist the necessities of the earthquake engineering. Proposals are suggested to guarantee the ductile behaviour of the steel of national production. (Author)

The Age of Saturn's Rings Constrained by the Meteoroid Flux Into the System

Science.gov (United States)

Kempf, S.; Altobelli, N.; Srama, R.; Cuzzi, J. N.; Estrada, P. R.

2017-12-01

The origin of Saturn's ring is still not known. There is an ongoing argument whether Saturn's ring are rather young or have been formed shortly after Saturn together with its satellites. The water-ice rings contain about 5% rocky material resulting from continuous meteoroid bombardment of the ring material with interplanetary micrometeoroids. Knowledge of the incoming mass flux would allow to estimate the ring's exposure time. Model calculations suggest exposure times of 108 years implying a late ring formation. This scenario is problematic because the tidal disruption of a Mimas-sized moon or of a comet within the planet's Roche zone would lead to a much larger rock content as observed today. Here we report on the measurement of the meteoroid mass flux into the Saturnian system obtained by the charge-sensitive entrance grid system (QP) of the Cosmic Dust Analyser (CDA) on the Cassini spacecraft. Interplanetary dust particles (IDPs) entering Saturn's sphere of gravitational influence are identified through the measurements of their speed vectors. We analyzed the full CDA data set acquired after Cassini's arrival at Saturn in 2004, identified the impact speed vectors of 128 extrinsic micrometeoroids ≥ 2 μm, and determined their orbital elements. On the basis of these measurements we determined the mass flux into the Saturnian system. Our preliminary findings are in support of an old ring. The knowledge of the meteoroids orbital elements allows us for the first time to characterize the meteoroid environment in the outer solar system based on direct measurements.

An application of ultrasonic inspection system (INER-SCAN) inspecting generator retaining rings

International Nuclear Information System (INIS)

Chen, L.C.; Hwang, S.C.

1994-01-01

The performances of the automatic ultrasonic inspecting and imaging system (INER-SCAN) developed by the NDT laboratory of the Institute of Nuclear Energy Research have been enhanced and much more improved to commercial level. With appropriate rearrangements of software libraries, it is used to inspect generator retaining rings which are critical structural rotor components that support the end-turn regions of the rotor wingings against centrifugal forces. The use of the INER-SCAN provides distinct advantages over other systems in terms of the reliability of inspection and the flexibility of system performance modifications. The INER-SCAN system assists users to select and modify ultrasonic parameters under computer-aided environment. In addition, the INER-SCAN system contains the necessary software functions to image the ultrasonic data (A-SCAN, B-SCAN, B'-SCAN, C-SCAN). The use of the imaging system makes it quite easy to evaluate various test parameters and their effects on the discrimination between geometric and IGSCC reflectors. Through experimental test, it is recognized that the system has powerful detectable capability which can find 0.2mm-depth slight scratch on the inner surface of retaining rings. This system can also be used on different generator retaining rings (different in terms of hidden design features) without the need for access to the dimension of retaining ring

Beam vacuum system of Brookhaven's muon storage ring

International Nuclear Information System (INIS)

Hseuth, H.C.; Snydstrup, L.; Mapes, M.

1995-01-01

A storage ring with a circumference of 45 m is being built at Brookhaven to measure the g-2 value of the muons to an accuracy of 0.35 ppm.. The beam vacuum system of the storage ring will operate at 10 -7 Torr and has to be completely non-magnetic. It consists of twelve sector chambers. The chambers are constructed of aluminum and are approximately 3.5 m in length with a rectangular cross-section of 16.5 cm high by 45 cm at the widest point. The design features, fabrication techniques and cleaning methods for these chambers are described. The beam vacuum system will be pumped by forty eight non-magnetic distributed ion pumps with a total pumping speed of over 2000 ell/sec. Monte Carlo simulations of the pressure distribution in the muon storage region are presented

Convergent synthesis of the HIJKLM ring system of ciguatoxin CTX3C.

Science.gov (United States)

Takamura, Hiroyoshi; Nishiuma, Naoki; Abe, Takashi; Kadota, Isao

2011-09-02

The HIJKLM ring system of ciguatoxin CTX3C was synthesized in a convergent manner. The key steps were a conjugate addition/alkylation sequence, spiroacetalization, intramolecular allylation, ring-closing metathesis, and hydrogenation to form the 36-α-methyl substituent.

Cuban Education in Neo-liberal Times: Socialist Revolutionaries and State Capitalism

Science.gov (United States)

Malott, Curry

2007-01-01

This article outlines the events that have led to Cuba's current engagement with global capitalism and the implications for Cuban education. The author looks at what Noam Chomsky (1999) has repeatedly referred to as "Cuba's trouble making in the hemisphere," such as it is. The author answers the question, "Why does the US government…

Digitizing dissent: cyborg politics and fluid networks in contemporary Cuban activism

Directory of Open Access Journals (Sweden)

Samuel Kellogg

2016-06-01

Full Text Available Communication technologies shape how political activist networks are produced and maintain themselves. In Cuba, despite ideologically and physically oppressive practices by the state, a severe lack of Internet access, and extensive government surveillance, a small network of bloggers and cyberactivists has achieved international visibility and recognition for its critiques of the Cuban government. This qualitative study examines the blogger collective known as Voces Cubanas in Havana, Cuba in 2012, advancing a new approach to the study of transnational activism and the role of technology in the construction of political narrative. Voces Cubanas is analyzed as a network of connections between human and non-human actors that produces and sustains powerful political alliances. Voces Cubanas and its allies work collectively to co-produce contentious political discourses, confronting the dominant ideologies and knowledges produced by the Cuban state. Transnational alliances, the act of translation, and a host of unexpected and improvised technologies play central roles in the production of these narratives, indicating new breed of cyborg sociopolitical action reliant upon fluid and flexible networks and the act of writing. 

Pb-210 behaviour in environmental samples from the Cuban east in 1993

International Nuclear Information System (INIS)

Perez Tamayo, L.; Suarez Pina, W.

1996-01-01

A method based in alpha and beta gross counting, is applied to research behaviour, during 1993, of Pb-210 in atmospheric depositional samples of six sites of the Cuban east. In five of these points, located distant from Cuban centers, the average Pb-210 aport to measured beta activity is predominant (80 +- 20 %) and maximum (> 50 % annual) is observed in coincidence with the first rain full peak. Such regularity may be explained, if assumption is made that principal source of Pb-210 are the continental air masses penetrating the insular atmosphere in winter and that mentioned radionuclide is deposit later with the spring rainfalls. In the sixth point, located at industrial zone, the alpha-beta activities rates are abnormally high, with maximums of 1.5 and 2.4 faced with peak raining and wet months respectively and probably originated by the input atmosphere of rich s in alpha emisors particles from industrial processes

RF SYSTEM FOR THE SNS ACCUMULATOR RING

International Nuclear Information System (INIS)

BLASKIEWICZ, M.; BRENNAN, J.M.; BRODOWSKI, J.; DELONG, J.; METH, M.; SMITH, K.; ZALTSMAN, A.

2001-01-01

During accumulation the RF beam current in the spallation neutron source ring rises from 0 to 50 amperes. A clean, 250 nanosecond gap is needed for the extraction kicker risetime. Large momentum spread and small peak current are needed to prevent instabilities and stopband related losses. A robust RF system meeting these requirements has been designed

Synthesis, structure and properties of tellurium cubane clusters of niobium and tantalum [M4(μ4-O)(μ3-Te)4(CN)12]6- (M=Nb, Ta)

International Nuclear Information System (INIS)

Fedin, V.P.; Kalinina, I.V.; Virovets, A.V.; Fenske, D.

2001-01-01

A new cubane cluster complex K 6 [Ta 4 (μ 4 -O)(μ 3 -Te) 4 (CN) 12 ] · KOH · 4H 2 O was prepared by high-temperature synthesis from a mixture of TaTe 4 and KCN with subsequent crystallization from aqueous solutions. The compound was characterized by the methods of cyclic voltammetry, X-ray diffraction analysis, IR, Raman and absorption spectroscopies. Comparative study of clusters [M 4 OTe 4 (CN) 12 ] 6- (M=Nb, Ta) containing μ 4 -O-ligands and being the first examples of molecular chalcogenide cubane complexes for group 5 metals of the Periodic System, was made [ru

Ring interconnection for distributed memory automation and computing system

Energy Technology Data Exchange (ETDEWEB)

Vinogradov, V I [Inst. for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation)

1996-12-31

Problems of development of measurement, acquisition and central systems based on a distributed memory and a ring interface are discussed. It has been found that the RAM LINK-type protocol can be used for ringlet links in non-symmetrical distributed memory architecture multiprocessor system interaction. 5 refs.

Mapping the Cuban Condition in Fernando Ortiz's Un catauro de cubanismos

Directory of Open Access Journals (Sweden)

Stephen Fay

2010-07-01

Full Text Available Explores the idiom-identity complex in Cuba in the first three decades of the twentieth century, concentrating on an emblematic catalog of the idiomatic raw material of the Cuban language community: Fernando Ortiz's vernacular dictionary, 'Un Catauro de cubanismos' from 1923. Author considers the critical complex of history, geography, and identity within Ortiz's dictionary.

The Omega Ring Imaging Cerenkov Detector readout system user's guide

International Nuclear Information System (INIS)

Hallewell, G.

1984-11-01

The manual describes the electronic readout system of the Ring Imaging Cerenkov Detector at the CERN Omega Spectrometer. The system is described in its configuration of September 1984 after the Rich readout system had been used in two Omega experiments. (U.K.)

31 CFR 515.415 - Travel to Cuba; transportation of certain Cuban nationals.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Travel to Cuba; transportation of... CONTROL REGULATIONS Interpretations § 515.415 Travel to Cuba; transportation of certain Cuban nationals... or a returning resident of the United States, from Cuba to the United States, unless otherwise...

Germination of somatic embryos of Psidium guajava L. cv. Cuban Red Dwarf EEA 18-40 in temporary immersion systems

Directory of Open Access Journals (Sweden)

Jorge Vilchez Perozo

2001-04-01

Full Text Available Somatic embryo germination of Psidium guajava L. cv. Cuban Red Dwarf EEA 18-40 in temporary immersion systems (TIS, in which somatic embryos were cultured in the heart-torpedo stage in MS mediun at mayor half strength salt and suplemented with: 0.25 mg.l-1 of 6-bencilaminopurine (6-BAP, 10 mg.l-1 of Biobras-6 (analogous of brasinoesteriode and 20 g.l-1 of sucrose. As control was used solid cultivation medium (2.5 g.l-1 Gellan gum, Spectrum® of same composition to the one used in the TIS. The variables germination percentage and fresh weight were evaluated statistically. After ten weeks of cultivation the largest values in germination percentage (91.04% and fresh weight (1.22 g were obtained in the TIS, being statistically different to those obtained in solid medium (9.79% and 1.03 g, respectively. Key words: in vitro plant, guayaba, regeneration, RITA®,somatic embryogenesis

Litter assessment on 99 Cuban beaches: A baseline to identify sources of pollution and impacts for tourism and recreation.

Science.gov (United States)

Botero, C M; Anfuso, G; Milanes, C; Cabrera, A; Casas, G; Pranzini, E; Williams, A T

2017-05-15

Litter presence was assessed on the entire Cuban coastline, and includes 99 beaches from all Cuban regions, during field work carried out in 2012 and 2015. A standard method verified in several countries was applied, which classified beaches for nine types of litter into four grades (A-excellent to D-poor). Almost half of the Cuban beaches obtained excellent cleanliness scores, although many needed to be better managed. In this baseline, the most common types of residue were general litter (8% grade D and 35% grades B/C) and potentially harmful litter (Tourism Impacts seems to be related to visitor origin therefore choices to develop sustainable tourism in rural and village beaches (64%) appears low, if beach cleaning gross investment is focused on resort beaches (24%). Finally, this paper highlights geographical distribution and types of litter patterns. Copyright © 2017 Elsevier Ltd. All rights reserved.

Survey of Digital Feedback Systems in High Current Storage Rings

International Nuclear Information System (INIS)

Teytelman, Dmitry

2003-01-01

In the last decade demand for brightness in synchrotron light sources and luminosity in circular colliders led to construction of multiple high current storage rings. Many of these new machines require feedback systems to achieve design stored beam currents. In the same time frame the rapid advances in the technology of digital signal processing allowed the implementation of these complex feedback systems. In this paper I concentrate on three applications of feedback to storage rings: orbit control in light sources, coupled-bunch instability control, and low-level RF control. Each of these applications is challenging in areas of processing bandwidth, algorithm complexity, and control of time-varying beam and system dynamics. I will review existing implementations as well as comment on promising future directions

Pulsed rf systems for large storage rings

International Nuclear Information System (INIS)

Wilson, P.B.

1979-03-01

The possibility is considered that by using a pulsed rf system a substantial reduction can be made in the rf power requirement for the next generation of large storage rings. For a ring with a sufficiently large circumference, the time between bunch passages, T/sub b/, can exceed the cavity filling time, T/sub f/. As the ratio T/sub b//T/sub f/ increases, it is clear that at some point the average power requirement can be reduced by pulsing the rf to the cavities. In this mode of operation, the rf power is turned on a filling time or so before the arrival of a bunch and is switched off again at the time of bunch passage. There is no rf energy in the accelerating structure, and hence no power dissipation, for most of the period between bunches

Possibility of persistent voltage observation in a system of asymmetric superconducting rings

International Nuclear Information System (INIS)

Burlakov, A.A.; Gurtovoi, V.L.; Ilin, A.I.; Nikulov, A.V.; Tulin, V.A.

2012-01-01

The possibility of observing persistent voltage in superconducting rings of different arm widths is experimentally investigated. It was previously found that switching of the arms between superconducting and normal states by an AC current induces DC voltage oscillation in the magnetic field with a period corresponding to the flux quantum inside the ring. We used systems with a large number of asymmetric rings connected in series to investigate the possibility of observing this quantum phenomenon near the superconducting transition, where thermal fluctuations lead to switching of ring segments without an external influence and the persistent current is much smaller than in the superconducting state. -- Highlights: ► A possibility to observe the persistent voltage is investigated experimentally. ► The persistent voltage is a DC voltage observed at thermodynamic equilibrium. ► It oscillates in magnetic field like the persistent current in superconducting ring. ► The period of the oscillations corresponds to the flux quantum inside the ring. ► The quantum oscillations of the DC voltage were observed on asymmetric rings.

“Latin-African” Solidarity – The Cuban Civilian Mission in Angola, 1975-1991

Directory of Open Access Journals (Sweden)

Christine Hatzky

2014-06-01

Full Text Available From 1975 to 1991, almost 500,000 Cubans were actively involved in the Angolan independence struggle and in building up Angola as an independent nation. Most of them were soldiers, but they also included doctors, teachers, building workers, and technicians.

The structure and stability of orbits in Hoag-like ring systems

Science.gov (United States)

Bannikova, Elena Yu

2018-05-01

Ring galaxies are amazing objects exemplified by the famous case of Hoag's Object. Here the mass of the central galaxy may be comparable to the mass of the ring, making it a difficult case to model mechanically. In a previous paper, it was shown that the outer potential of a torus (ring) can be represented with good accuracy by the potential of a massive circle with the same mass. This approach allows us to simplify the problem of the particle motion in the gravitational field of a torus associated with a central mass by replacing the torus with a massive circle. In such a system, there is a circle of unstable equilibrium that we call `Lagrangian circle' (LC). Stable circular orbits exist only in some region limited by the last possible circular orbit related to the disappearance of the extrema of the effective potential. We call this orbit `the outermost stable circular orbit' (OSCO) by analogy with the innermost stable circular orbit (ISCO) in the relativistic case of a black hole. Under these conditions, there is a region between OSCO and LC where the circular motion is not possible due to the competition between the gravitational forces by the central mass and the ring. As a result, a gap in the matter distribution can form in Hoag-like system with massive rings.

Evaluation of gas emissions and environmental impact of a Cuban thermal power plant

International Nuclear Information System (INIS)

Colas Aroche, Juan Alberto; Alvarez Hernandez, Orlando H; Fuentes Quevedo, Eduardo; Teutelo Nunnez, Raisa

2006-01-01

The present work shows the results obtained in the characterization of gas emissions and the impact of two fire-tube boilers in a Cuban thermal power plant. The results of the SO 2 and NO X sampling were collected in specific solutions for each pollutant. The sampling of suspended particulates in chimneys/pipes/stacks was made by collecting them in a filterholder for their analysis by means of the gravimetric method. Flow measurements were also made by using pressure sensors of Pilot tube-type speedometers. The dispersion modelling of pollutants poured out of the chimneys was developed running the program for the concentration calculation from continuous industrial sources and following the methodology approved by the Cuban standard according to Berliand model. The authors conclude that when burning national crude oil in the studied boilers, sulphur dioxide concentrations and suspended particulates are higher than the internationally standardized level

Photometric and spectroscopic evidence for a dense ring system around Centaur Chariklo

Science.gov (United States)

Duffard, R.; Pinilla-Alonso, N.; Ortiz, J. L.; Alvarez-Candal, A.; Sicardy, B.; Santos-Sanz, P.; Morales, N.; Colazo, C.; Fernández-Valenzuela, E.; Braga-Ribas, F.

2014-08-01

Context. A stellar occultation observed on 3rd June 2013 revealed the presence of two dense and narrow rings separated by a small gap around the Centaur object (10 199) Chariklo. The composition of these rings is not known. We suspect that water ice is present in the rings, as is the case for Saturn and other rings around the giant planets. Aims: In this work, we aim to determine if the variability in the absolute magnitude of Chariklo and the temporal variation of the spectral ice feature, even when it disappeared in 2007, can be explained by an icy ring system whose aspect angle changes with time. Methods: We explained the variations on the absolute magnitude of Chariklo and its ring by modeling the light reflected by a system as the one described above. Using X-shooter at VLT, we obtained a new reflectance spectra. We compared this new set of data with the ones available in the literature. We showed how the water ice feature is visible in 2013 in accordance with the ring configuration, which had an opening angle of nearly 34° in 2013. Finally, we also used models of light scattering to fit the visible and near-infrared spectra that shows different characteristics to obtain information on the composition of Chariklo and its rings. Results: We showed that absolute photometry of Chariklo from the literature and new photometric data that we obtained in 2013 can be explained by a ring of particles whose opening angle changes as a function of time. We used the two possible pole solutions for the ring system and found that only one of them, α = 151.30 ± 0.5, δ = 41.48 ± 0.2° (λ = 137.9 ± 0.5, β = 27.7 ± 0.2°), provides the right variation of the aspect angle with time to explain the photometry, whereas the other possible pole solution fails to explain the photometry. From spectral modeling, we derived the composition of the Chariklo surface and that of the rings using the result on the pole solution. Chariklo surface is composed with about 60% of amorphous

Hydrogen Evolution on Supported Incomplete Cubane-type [Mo3S4](4+) Electrocatalysts

DEFF Research Database (Denmark)

Jaramillo, Thomas; Bonde, Jacob Lindner; Zhang, Jingdong

2008-01-01

Electrocatalytic properties of biomimetic supported incomplete cubane-type [Mo3S4](4+) clusters are investigated. The activity toward the hydrogen evolution reaction (HER) is evaluated on both a high surface area gas diffusion electrode in a membrane electrode assembly and on highly orientated...

Characterizing exo-ring systems around fast-rotating stars using the Rossiter-McLaughlin effect

Science.gov (United States)

de Mooij, Ernst J. W.; Watson, Christopher A.; Kenworthy, Matthew A.

2017-12-01

Planetary rings produce a distinct shape distortion in transit light curves. However, to accurately model such light curves the observations need to cover the entire transit, especially ingress and egress, as well as an out-of-transit baseline. Such observations can be challenging for long period planets, where the transits may last for over a day. Planetary rings will also impact the shape of absorption lines in the stellar spectrum, as the planet and rings cover different parts of the rotating star (the Rossiter-McLaughlin effect). These line-profile distortions depend on the size, structure, opacity, obliquity and sky-projected angle of the ring system. For slow-rotating stars, this mainly impacts the amplitude of the induced velocity shift; however, for fast-rotating stars the large velocity gradient across the star allows the line distortion to be resolved, enabling direct determination of the ring parameters. We demonstrate that by modelling these distortions we can recover ring system parameters (sky-projected angle, obliquity and size) using only a small part of the transit. Substructure in the rings, e.g. gaps, can be recovered if the width of the features (δW) relative to the size of the star is similar to the intrinsic velocity resolution (set by the width of the local stellar profile, γ) relative to the stellar rotation velocity (v sini, i.e. δW/R* ≳ vsini/γ). This opens up a new way to study the ring systems around planets with long orbital periods, where observations of the full transit, covering the ingress and egress, are not always feasible.

Design considerations for a feedback system to control self-bunching in ion-storage rings

International Nuclear Information System (INIS)

Ziemann, V.

2001-02-01

We discuss the feasibility of a feedback system to cure self-bunching of the electron-cooled coasting ion-beam in CELSIUS. Such a system may also aid stable operation of accumulator rings for future spallation neutron sources or heavy ion rings used for inertial fusion energy production

A two-dimensional hydrogen-bonded water layer in the structure of a cobalt(III) cubane complex.

Science.gov (United States)

Qi, Ji; Zhai, Xiang-Sheng; Zhu, Hong-Lin; Lin, Jian-Li

2014-02-01

A tetranuclear Co(III) oxide complex with cubane topology, tetrakis(2,2'-bipyridine-κ(2)N,N')di-μ2-carbonato-κ(4)O:O'-tetra-μ3-oxido-tetracobalt(III) pentadecahydrate, [Co4(CO3)2O4(C10H8N2)4]·15H2O, with an unbounded hydrogen-bonded water layer, has been synthesized by reaction of CoCO3 and 2,2'-bipyridine. The solvent water molecules form a hydrogen-bonded net with tetrameric and pentameric water clusters as subunits. The Co4O4 cubane-like cores are sandwiched between the water layers, which are further stacked into a three-dimensional metallo-supramolecular network.

The Soviet-Cuban Connection in Central America and the Caribbean

Science.gov (United States)

1985-04-01

bly for civilian use, was built primarily by armed clandestinely ferrying a cargo of military supplies to Cubans, despite the high unemployment on the...reorm an deocraic lecion. Th sucesive population now either own their land outright or par- governments of El Salvador have worked to follow ticipate as...launcher, airstrips and unloading their cargo of arms and am-munition. Air drops are also used. .’.. subsequently captured by communist forces after

On the Aharonov-Casher system and the Landau-Aharonov-Casher system confined to a two-dimensional quantum ring

International Nuclear Information System (INIS)

Bakke, K.; Furtado, C.

2012-01-01

We study the quantum dynamics of a neutral particle in the Aharonov-Casher system and in the Landau-Aharonov-Casher system confined to a two-dimensional quantum ring, a quantum dot, and a quantum anti-dot potentials described by the Tan-Inkson model [W.-C. Tan and J. C. Inkson, Semicond. Sci. Technol. 11, 1635 (1996)]. We show, in the Aharonov-Casher system, that bound states can be achieved when the neutral particle is confined to the two-dimensional quantum ring and the quantum dot and discuss the appearance of persistent currents. In the Landau-Aharonov-Casher system, we show that bound states can be achieved when the neutral particle is confined to the quantum anti-dot, quantum dot, and the two-dimensional quantum ring, but there are no persistent currents.

Knowing the Place for the First Time: A Cuban Exile’s Story

Directory of Open Access Journals (Sweden)

Alejandra Morena

2009-03-01

Full Text Available Playa Abierta is a modern beach-side resort, one hundred kilometres west of Havana. Developed as a private resort in the 1950s, it was seized by the new revolutionary Cuban government in 1959 after its owner fled precipitately to Miami. This autobiographically centred and personally narrated paper reviews the history of Playa Abierta 1956 – 2006 through the eyes of a Cuban New Zealander ‘Marta’ whose uncle first developed the estate. In 1956 her holidays spent at Playa Abierta as a little girl were her most treasured Cuban moments. ‘At this altar’, she says, ‘my uncle was the high priest.’ In 1996 - after a 36-year absence from her native land - she returned for a visit, the only member of her extended family to have done so. Boldly and unannounced she walked through her uncle’s house – by then converted into a military recreational camp. On a subsequent visit, she met with members of her uncle’s domestic staff whose relationship to that same loved beach was by then of many decades. Whose Playa Abierta was she re-visiting now? Who were the true claimants to that family sacred site? Today as she reflects on the private and public meaning of Playa Abierta, her exultation has given way to more complex feelings. The wonder at re-discovering the beach’s beauty was overladen with the guilt of returning to Cuba while still under Castro’s communist rule. Her sense of belonging was later undermined by a sad realisation that those who had stayed behind were also Playa Abierta’s claimants. Above all, she is torn between family loyalties and the promise of a Revolution betrayed.

Numerical study on the lubrication performance of compression ring-cylinder liner system with spherical dimples.

Directory of Open Access Journals (Sweden)

Cheng Liu

Full Text Available The effects of surface texture on the lubrication performance of a compression ring-cylinder liner system are studied in this paper. By considering the surface roughness of the compression ring and cylinder liner, a mixed lubrication model is presented to investigate the tribological behaviors of a barrel-shaped compression ring-cylinder liner system with spherical dimples on the liner. In order to determine the rupture and reformulation positions of fluid film accurately, the Jacoboson-Floberg-Olsson (JFO cavitation boundary condition is applied to the mixed lubrication model for ensuring the mass-conservative law. On this basis, the minimum oil film thickness and average friction forces in the compression ring-cylinder liner system are investigated under the engine-like conditions by changing the dimple area density, radius, and depth. The wear load, average friction forces, and power loss of the compression ring-cylinder liner system with and without dimples are also compared for different compression ring face profiles. The results show that the spherical dimples can produce a larger reduction of friction in mixed lubrication region, and reduce power loss significantly in the middle of the strokes. In addition, higher reduction percentages of average friction forces and wear are obtained for smaller crown height or larger axial width.

Structural and magnetic characterization of three tetranuclear Cu(II) complexes with face-sharing-dicubane/double-open-cubane like core framework

International Nuclear Information System (INIS)

Paul, Aparup; Bertolasi, Valerio; Figuerola, Albert; Manna, Subal Chandra

2017-01-01

Three novel tetranuclear copper(II) complexes namely [Cu 4 (L 1 ) 4 ]∙2(dmf) (1), [Cu 4 (L 1 ) 4 ] (2) and [Cu 4 (L 2 ) 2 (HL 2 ) 2 (H 2 O) 2 ]∙2(ClO 4 )·6(H 2 O) (3) (H 2 L 1 , (E)−2-((1-hydroxybutan-2-ylimino)methyl)phenol; H 2 L 2 , (E)−2-((1-hydroxybutan-2-ylimino)methyl)−6-methoxyphenol)) were synthesized from the self-assembly of copper(II) perchlorate and the tridentate Schiff base ligands. The structural determination reveals that crystallizes in the monoclinic system with space group C2/c, whereas both the and crystallize in the triclinic system with space group P-1. and possess face-sharing dicubane core, on the other hand complex 3 has double open cubane core structure. The copper(II) ions in the cubane core are in distorted square planar geometries, and weak π…π and C–H…π interactions lead to formation of a 2D supramolecular architecture for and . At room temperature and , exhibit fluorescence with a quantum yield (Φ s ) of 0.47, 0.49 and 0.38, respectively. Variable temperature magnetic susceptibility measurements in the range 2–300 K indicate an overall weak antiferromagnetic exchange coupling in all complexes. The PHI program was used to study their magnetic behaviour. In agreement with their face-sharing dicubane structure, a Hamiltonian of the type H =– J 1 (S 1 S 2 +S 1 S 2’ +S 1' S 2 +S 1' S 2’ ) – J 2 S 1 S 1’ , where S 1 = S 1’ = S 2 = S 2’ = S Cu =1/2, was used for studying and . Simulations performed suggest magnetic exchange constants with values close to J 1 =−20 cm −1 and J 2 =0 cm -1 for these complexes. On the other hand, the spin Hamiltonian H =– J 1 (S 1 S 4 +S 2 S 3 ) – J 2 (S 1 S 3 +S 2 S 4 ) – J 3 S 1 S 2 , where S 1 = S 2 = S 3 = S 4 = S Cu =1/2, was used to study the magnetic behaviour of the double open cubane core of and a good agreement between the experimental and simulated results was found by using the parameters g 1 = g 2 =2.20, g 3 = g 4 =2.18, J 1 =−36 cm -1 , J 2

‘We feel stupid and we shouldn’t.’ Towards developing a communication support system for Cuban-trained medical students

Directory of Open Access Journals (Sweden)

Gasiorek, Jessica

2014-12-01

Full Text Available This article presents a case study of a small group of South African medical students who have returned to South Africa after six years of medical education in Cuba, where they were trained in a different language (Spanish and medical system (Cuban from what they will ultimately practice in as South African doctors. This study sought to better understand the linguistic, cultural, and communicative challenges that this group faced upon returning to South Africa, with the ultimate goal of creating materials to support the students’ language learning in the clinical domain. The researchers found that students reported considerable difficulties with (re-integrating into South African culture and clinical contexts; specific issues included encountering different types of medical issues in South Africa compared to Cuba and difficulty in understanding and using medical terminology in English and Afrikaans. This case study concludes with specific recommendations for developing learning materials that address these students’ unique linguistic and communicative needs.

Real-time track-less Cherenkov ring fitting trigger system based on Graphics Processing Units

Science.gov (United States)

Ammendola, R.; Biagioni, A.; Chiozzi, S.; Cretaro, P.; Cotta Ramusino, A.; Di Lorenzo, S.; Fantechi, R.; Fiorini, M.; Frezza, O.; Gianoli, A.; Lamanna, G.; Lo Cicero, F.; Lonardo, A.; Martinelli, M.; Neri, I.; Paolucci, P. S.; Pastorelli, E.; Piandani, R.; Piccini, M.; Pontisso, L.; Rossetti, D.; Simula, F.; Sozzi, M.; Vicini, P.

2017-12-01

The parallel computing power of commercial Graphics Processing Units (GPUs) is exploited to perform real-time ring fitting at the lowest trigger level using information coming from the Ring Imaging Cherenkov (RICH) detector of the NA62 experiment at CERN. To this purpose, direct GPU communication with a custom FPGA-based board has been used to reduce the data transmission latency. The GPU-based trigger system is currently integrated in the experimental setup of the RICH detector of the NA62 experiment, in order to reconstruct ring-shaped hit patterns. The ring-fitting algorithm running on GPU is fed with raw RICH data only, with no information coming from other detectors, and is able to provide more complex trigger primitives with respect to the simple photodetector hit multiplicity, resulting in a higher selection efficiency. The performance of the system for multi-ring Cherenkov online reconstruction obtained during the NA62 physics run is presented.

A Study of Storage Ring Requirements for an Explosive Detection System Using NRA Method.

Energy Technology Data Exchange (ETDEWEB)

Wang, T. F. (Tai-Sen F.); Kwan, T. J. T. (Thomas J. T.)

2005-01-01

The technical feasibility of an explosives detection system based on the nuclear resonance absorption (NRA) of gamma rays in nitrogen-rich materials was demonstrated at Los Alamos National Laboratory (LANL) in 1993 by using an RFQ proton accelerator and a tomographic imaging prototype. The study is being continued recently to examine deployment of such an active interrogation system in realistic scenarios. The approach is to use an accelerator and electron-cooling-equipped storage rings(s) to provide the high quality and high current proton beam needed in a practical application. In this work, we investigate the requirements on the storage ring(s) with external gamma-ray-production target for a variant of the airport luggage inspection system considered in the earlier LANL experiments. Estimations are carried out based on the required inspection throughput, the gamma ray yield, the proton beam emittance growth due to scatters with the photon-production target, beam current limit in the storage ring, and the electron-cooling rate. Studies using scaling and reasonable parameter values indicate that it is possible to use no more than a few storage rings per inspection station in a practical NRA luggage inspection complex having more than ten inspection stations.

Study of RF system of Hefei storage ring under injection

International Nuclear Information System (INIS)

Xu Hongliang; Wang Lin; Li Yongjun; Huang Guirong; Zhang Pengfei; Li Weimin; Liu Zuping; He Duohui

2004-01-01

In this paper, the beam loading effect of RF system and the conditions of Robinson instability are analyzed in detail. By the study of the injection beam intensity limit dependent on detune angle and visible detune angle, it is found that the storage ring can be injected to more than 300 mA current intensity to attain the design target of phase II project in the lower energy injection situation of Hefei Storage Ring if a certain power is feed in the RF cavity and a certain tuning angle of the RF cavity is set

Normalization of US-Cuban Relations: Obama Doctrine and International Security in the Western Hemisphere

Directory of Open Access Journals (Sweden)

Piotr Łaciński

2015-12-01

Full Text Available Strained relations between the US and Cuba after the victory of the Cuban revolution were a permanent element of the destabilization of international security in the Western Hemisphere. During the Cold War, this destabilization was a function of the East-West confrontation. Since the end of Cold War the importance of Cuba as a Western Hemisphere entity hostile to the United States has diminished radically. Definite steps to normalize relations with Cuba have been taken only in 2014. The media named the change of policies of the US towards Cuba (and Iran as the Obama Doctrine. This article will try to prove that the continuation of the confron-tational and hostile US-Cuban relations after the collapse of the Eastern bloc was an exceptional and "unnatural" phenomenon from the perspective of realistic school of international relations, both for Washington and Havana.

El enfoque epidemiologico del sistema de salud de Cuba The epidemiologic approach of the Cuban health system

Directory of Open Access Journals (Sweden)

Silvia Martínez Calvo

1999-08-01

mensurar la distancia entre lo ideal y lo real. En conclusión, se reconoce cierto vacío entre la argumentación teórica y la práctica epidemiológica en el Sistema Nacional de Salud, aunque sean inobjetables los avances en el ámbito sanitario en estas casi cuatro décadas. Resulta ineludible el desafío que esto representa para alcanzar el liderazgo epidemiológico que en el discurso se promueve, para lo cual la reforma del sector salud emerge como un excelente y oportuno espacio.The international recognition of the achievements of the Cuban health system, the stability -questioned on some occasions - of health indicators, and the enormous human resources and materials invested to develop the policies and national sanitary strategies comprise an excellent field to analyze the epidemiological contribution to those positive results in the health area. Among those outstanding results, the longer life expectancy, the low mortality rates, infant mortality, and mortality due to infectious and parasitic diseases partly due to the elimination or eradication of a group of diseases preventable by immunization. Were these results reached by an epidemiologically oriented health system? Do the procedures carried out allow for the proposal of a Cuban School of Epidemiology? The objective of this paper is to offer answers to these queries through a critical appraisal on the presumable epidemiological orientation of the health system, and the incorporation of epidemiological thinking in the sanitary strategies that have been designed and developed in Cuba. An arbitrary, but notorious dichotomy, the Seminar on the "Uses and Perspectives of Epidemiology", held in Buenos Aires in 1983, has traced rules for the epidemiological performance in the Region as a whole and contributed to the analysis above. The dichotomy -before and after the Seminar - created the national scenarios for practicing epidemiology at the academic, investigative and health services levels, supported on 4 basic

Soil hydraulic properties of Cuban soils

International Nuclear Information System (INIS)

Ruiz, M.E.; Medina, H.

2004-01-01

Because soil hydraulic properties are indispensable for determining soil water retention and soil water movement, their input for deterministic crop simulation models is essential. From these models is possible to access the effect of the weather changes, soil type or different irrigation schedules on crop yields. With these models, possibilities are provided to answer questions regarding virtual 'what happen if' experiments with a minimum of fieldwork. Nevertheless, determining soil hydraulic properties can be very difficult owing to unavailability of necessary equipment or the lack of personal with the proper knowledge for those tasks. These deficiencies are a real problem in developing countries, and even more so when there is not enough financial possibilities for research work. This paper briefly presents the way these properties have been accessed for Cuban soils, which methods have been used and the work now in progress. (author)

Structure and dynamics of ringed galaxies

International Nuclear Information System (INIS)

Buta, R.J.

1984-01-01

In many spiral and SO galaxies, single or multiple ring structures are visible in the disk. These inner rings (r), outer rings (R), and nuclear rings (nr) were investigated by means of morphology, photometry, and spectroscopy in order to provide basic data on a long neglected phenomenon. The metric properties of each ring are investigated and found to correlate with the structure of the parent galaxy. When properly calibrated, inner rings in barred (SB) systems can be used as geometric extragalactic distance indicators to distances in excess of 100 Mpc. Other statistics are presented that confirm previous indications that the rings have preferred shapes, relative sizes, and orientations with respect to bars. A survey is made of the less homogeneous non-barred (SA) ringed systems, and the causes of the inhomogeneity are isolated. It is shown that rings can be identified in multiple-ring SA systems that are exactly analogous to those in barred spirals

New safety performance indicators for safety assessment of radioactive waste disposal facilities. Cuban experience

International Nuclear Information System (INIS)

Peralta Vital, J.L.; Castillo, R.G.; Olivera, J.

2002-01-01

The paper shows the Cuban experience on implementing geological disposal of radioactive waste and the necessity for identifying new safety performance indicators for the safety assessment (SA) of radioactive waste disposal facilities. The selected indicator was the concentration of natural radioactive elements (U, Ra, Th, K) in the Cuban geologic environment. We have carried out a group of investigations, which have allowed characterising the concentration for the whole Country, creating a wide database where this indicator is associated with the lithology. The main lithologies in Cuba are: the sedimentary rocks (70 percent of national occurrence), which are present in the three regions (limestone and lutite), and finally the igneous and metamorphic rocks. The results show the concentrations ranges of the natural radionuclides associated fundamentally to the variation in the lithology and geographical area of the Country. In Cuba, the higher concentration (ppm) of Uranium and Radium are referenced to the Central region associated to Skarn, while for Thorium (ppm) and Potassium (%), in the East region the concentration peaks in Tuffs have been found. The concentrations ranges obtained are preliminary, they characterise the behaviour of this parameter for the Cuban geology, but they do not represent limits for safety assessment purposes yet. Also other factors should be taken into account as the assessment context, time scales and others assumptions before establishing the final concentration limits for the natural radionuclides as a radiological and nuclear safety performance indicator complementary to dose and risk for safety assessment for radiological and nuclear facilities. (author)

An innovative seismic bracing system based on a superelastic shape memory alloy ring

International Nuclear Information System (INIS)

Gao, Nan; Jeon, Jong-Su; DesRoches, Reginald; Hodgson, Darel E

2016-01-01

Shape memory alloys (SMAs) have great potential in seismic applications because of their remarkable superelasticity. Seismic bracing systems based on SMAs can mitigate the damage caused by earthquakes. The current study investigates a bracing system based on an SMA ring which is capable of both re-centering and energy dissipation. This lateral force resisting system is a cross-braced system consisting of an SMA ring and four tension-only cable assemblies, which can be applied to both new construction and seismic retrofit. The performance of this bracing system is examined through a quasi-static cyclic loading test and finite element (FE) analysis. This paper describes the experimental design in detail, discusses the experimental results, compares the performance with other bracing systems based on SMAs, and presents an Abaqus FE model calibrated on the basis of experimental results to simulate the superelastic behavior of the SMA ring. The experimental results indicate that the seismic performance of this system is promising in terms of damping and re-centering. The FE model can be used in the simulation of building structures using the proposed bracing system. (paper)

Development of a circular shape Si-PM-based detector ring for breast-dedicated PET system

Science.gov (United States)

Nakanishi, Kouhei; Yamamoto, Seiichi; Watabe, Hiroshi; Abe, Shinji; Fujita, Naotoshi; Kato, Katsuhiko

2018-02-01

In clinical situations, various breast-dedicated positron emission tomography (PET) systems have been used. However, clinical breast-dedicated PET systems have polygonal detector ring. Polygonal detector ring sometimes causes image artifact, so complicated reconstruction algorithm is needed to reduce artifact. Consequently, we developed a circular detector ring for breast-dedicated PET to obtain images without artifact using a simple reconstruction algorithm. We used Lu1.9Gd0.1SiO5 (LGSO) scintillator block which was made of 1.5 x 1.9 x 15 mm pixels that were arranged in an 8 x 24 matrix. As photodetectors, we used silicon photomultiplier (Si-PM) arrays whose channel size was 3 x 3 mm. A detector unit was composed of four scintillator blocks, 16 Si-PM arrays and a light guide. The developed detector unit had angled configuration since the light guide was bending. A detector unit had three gaps with an angle of 5.625° between scintillator blocks. With these configurations, we could arrange 64 scintillator blocks in nearly circular shape (regular 64-sided polygon) using 16 detector units. The use of the smaller number of detector units could reduce the size of the front-end electronics circuits. The inner diameter of the developed detector ring was 260 mm. This size was similar to those of brain PET systems, so our breast-dedicated PET detector ring can measure not only breast but also brain. Measured radial, tangential and axial spatial resolution of the detector ring reconstructed by the filtered back-projection (FBP) algorithm were 2.1 mm FWHM, 2.0 mm FWHM and 1.7 mm FWHM at center of field of view (FOV), respectively. The sensitivity was 2.0% at center of the axial FOV. With the developed detector ring, we could obtain high resolution image of the breast phantom and the brain phantom. We conclude that our developed Si-PM-based detector ring is promising for a high resolution breast-dedicated PET system that can also be used for brain PET system.

Planetary Rings

Science.gov (United States)

Nicholson, P. D.

2001-11-01

A revolution in the studies in planetary rings studies occurred in the period 1977--1981, with the serendipitous discovery of the narrow, dark rings of Uranus, the first Voyager images of the tenuous jovian ring system, and the many spectacular images returned during the twin Voyager flybys of Saturn. In subsequent years, ground-based stellar occultations, HST observations, and the Voyager flybys of Uranus (1986) and Neptune (1989), as well as a handful of Galileo images, provided much additional information. Along with the completely unsuspected wealth of detail these observations revealed came an unwelcome problem: are the rings ancient or are we privileged to live at a special time in history? The answer to this still-vexing question may lie in the complex gravitational interactions recent studies have revealed between the rings and their retinues of attendant satellites. Among the four known ring systems, we see elegant examples of Lindblad and corotation resonances (first invoked in the context of galactic disks), electromagnetic resonances, spiral density waves and bending waves, narrow ringlets which exhibit internal modes due to collective instabilities, sharp-edged gaps maintained via tidal torques from embedded moonlets, and tenuous dust belts created by meteoroid impact onto parent bodies. Perhaps most puzzling is Saturn's multi-stranded, clumpy F ring, which continues to defy a simple explanation 20 years after it was first glimpsed in grainy images taken by Pioneer 11. Voyager and HST images reveal a complex, probably chaotic, dynamical interaction between unseen parent bodies within this ring and its two shepherd satellites, Pandora and Prometheus. The work described here reflects contributions by Joe Burns, Jeff Cuzzi, Luke Dones, Dick French, Peter Goldreich, Colleen McGhee, Carolyn Porco, Mark Showalter, and Bruno Sicardy, as well as those of the author. This research has been supported by NASA's Planetary Geology and Geophysics program and the

The beam loss monitoring system for HLS storage ring

CERN Document Server

Li Yu Xiong; Li Wei; Li Jue Xin; Liu Zu Ping; Shao Bei Bei

2001-01-01

A beam loss monitoring system has been established at HLS. This paper gives its principle and scientific grounds. Study on the ring's TBA structure and utilization of Monte-Carlo calculation to the shower electrons is important in its design. The system composition and performance are also introduced. The detector BLMs, data acquisition devices and host PC are linked via CAN bus. This system is helpful to analyze beam loss distribution and regulate the machine operation parameters.

Auto-production of biosurfactants reverses the coffee ring effect in a bacterial system

Science.gov (United States)

Sempels, Wouter; de Dier, Raf; Mizuno, Hideaki; Hofkens, Johan; Vermant, Jan

2013-04-01

The deposition of material at the edge of evaporating droplets, known as the ‘coffee ring effect’, is caused by a radially outward capillary flow. This phenomenon is common to a wide array of systems including colloidal and bacterial systems. The role of surfactants in counteracting these coffee ring depositions is related to the occurrence of local vortices known as Marangoni eddies. Here we show that these swirling flows are universal, and not only lead to a uniform deposition of colloids but also occur in living bacterial systems. Experiments on Pseudomonas aeruginosa suggest that the auto-production of biosurfactants has an essential role in creating a homogeneous deposition of the bacteria upon drying. Moreover, at biologically relevant conditions, intricate time-dependent flows are observed in addition to the vortex regime, which are also effective in reversing the coffee ring effect at even lower surfactant concentrations.

Ring retroreflector system consisting of cube-corner reflectors with special coating

International Nuclear Information System (INIS)

Burmistrov, V B; Sadovnikov, M A; Sokolov, A L; Shargorodskiy, V D

2013-01-01

The ring retroreflector system (RS) consisting of cubecorner reflectors (CCRs) with a special coating of reflecting surfaces, intended for uniaxially Earth-oriented navigation satellites, is considered. The error of distance measurement caused by both the laser pulse delay in the CCR and its spatial position (CCR configuration) is studied. It is shown that the ring RS, formed by the CCR with a double-spot radiation pattern, allows the distance measurement error to be essentially reduced. (nanogradient dielectric coatings and metamaterials)

Design considerations for a digital feedback system to control self-bunching in ion-storage rings

Directory of Open Access Journals (Sweden)

V. Ziemann

2001-04-01

Full Text Available We discuss the feasibility of a digital feedback system to cure self-bunching of the electron-cooled coasting ion beam in ion-storage rings such as CELSIUS [S. Holm, A. Johansson, S. Kullander, and D. Reistad, Phys. Scr. 34, 513–532 (1986]. Such a system is based on a fast digital filter that acts as a tunable artificial wake potential. It may also aid stable operation of accumulator rings for future spallation neutron sources or heavy ion rings used for inertial fusion energy production.

A new systematic calibration method of ring laser gyroscope inertial navigation system

Science.gov (United States)

Wei, Guo; Gao, Chunfeng; Wang, Qi; Wang, Qun; Xiong, Zhenyu; Long, Xingwu

2016-10-01

Inertial navigation system has been the core component of both military and civil navigation systems. Before the INS is put into application, it is supposed to be calibrated in the laboratory in order to compensate repeatability error caused by manufacturing. Discrete calibration method cannot fulfill requirements of high-accurate calibration of the mechanically dithered ring laser gyroscope navigation system with shock absorbers. This paper has analyzed theories of error inspiration and separation in detail and presented a new systematic calibration method for ring laser gyroscope inertial navigation system. Error models and equations of calibrated Inertial Measurement Unit are given. Then proper rotation arrangement orders are depicted in order to establish the linear relationships between the change of velocity errors and calibrated parameter errors. Experiments have been set up to compare the systematic errors calculated by filtering calibration result with those obtained by discrete calibration result. The largest position error and velocity error of filtering calibration result are only 0.18 miles and 0.26m/s compared with 2 miles and 1.46m/s of discrete calibration result. These results have validated the new systematic calibration method and proved its importance for optimal design and accuracy improvement of calibration of mechanically dithered ring laser gyroscope inertial navigation system.

Electronic de-multipliers II (ring-shape systems)

International Nuclear Information System (INIS)

Raievski, V.

1948-09-01

This report describes a new type of ring-shape fast electronic counter (de-multiplier) with a resolution capacity equivalent to the one made by Regener (Rev. of Scientific Instruments USA 1946, 17, 180-89) but requiring two-times less electronic valves. This report follows the general description of electronic de-multipliers made by J. Ailloud (CEA--001). The ring comprises 5 flip-flop circuits with two valves each. The different elements of the ring are calculated with enough details to allow the transfer of this calculation to different valve types. (J.S.)

Feasible conditions for converting Cuban cane molasses into alcohol

Energy Technology Data Exchange (ETDEWEB)

Luchev, S

1968-01-01

Conditions for fermentation of Cuban cane molasses were found: 0.5 to 1.0% yeast, addition of 100g. H/sub 3/PO/sub 4/, 1 to 2 kg urea or (NH/sub 4/)/sub 2/SO/sub 4/ to 1 ton molasses, and fermentation at high molasses concentrations. During the process, solid residue formed containing mainly CaSO/sub 4/; this was limited when the molasses was clarified before the fermentation, or when it was distilled without the use of acids (particularly H/sub 2/SO/sub 4/), or when fermented molasses with a low alcohol content was distilled.

MEDICAL TOURISM : Demand for Cuban Medical Tourism by Russian Consumers

OpenAIRE

Ulanova, Anastasia

2015-01-01

Medical tourism, often addressed as health tourism, is a new concept in terms of tourism industry in general, and it is also one of the rapidly developing and growing ones. This thesis gives information on the medical tourism in general and its history. It also revises the development stages of the medical tourism in the world. Cuban medical tourism is analyzed on its own, as well as Russian medical tourism and the demand for it. Medical tourism is rather popular among Russians due to various...

Data exchange system in cooler-storage-ring virtual accelerator

International Nuclear Information System (INIS)

Liu Wufeng; Qiao Weimin; Jing Lan; Guo Yuhui

2009-01-01

The data exchange system of the cooler-storage-ring (CSR) control system for heavy ion radiotherapy has been introduced for the heavy ion CSR at Lanzhou (HIRFL-CSR). Using techniques of Java, component object model (COM), Oracle, DSP and FPGA, this system can achieve real-time control of magnet power supplies sanctimoniously, and control beams and their switching in 256 energy levels. It has been used in the commissioning of slow extraction for the main CSR (CSRm), showing stable and reliable performance. (authors)

Endemics under threat: an assessment of the conservation status of Cuban bats

Directory of Open Access Journals (Sweden)

Carlos Mancina

2007-07-01

Full Text Available Abstract Reviewing available information from published literature, museum database, personal communications and from the authors own field data, the conservation status of Cuban bats has been assessed using six qualitative parameters: abundance, distribution, roosting habits, aggregation level, forest dependence, and degree of endemism. The resulting Red List is analogous to that of the IUCN, species having been included in four categories of risk. Four out of the 26 extant bats of Cuba should be considered endangered, four vulnerable to extinction, twelve potentially threatened, and six in a stable situation. Most of the species of bats endemic to Cuba are under some form of threat. The major threats to the survival of Cuban bats are the destruction of forests and the modification of caves, the latter being critical habitats for the mostly cave-dwelling Cuban bat fauna. We argue that its conservation should be the result of a cooperative effort promoting research and habitat management. Riassunto Endemismi minacciati: una valutazione dello stato di conservazione dei chirotteri cubani. Lo stato di conservazione dei chirotteri cubani è stato valutato a partire da sei parametri qualitativi: abbondanza, distribuzione, roost utilizzati, livello di aggregazione, dipendenza da ambienti forestali e grado di endemismo. A questo scopo sono state esaminate le informazioni bibliografiche, i database dei musei e dati non pubblicati, in parte raccolti dagli stessi autori. La Lista Rossa risultante è analoga a quella dell’IUCN, comprendendo quattro categorie di rischio crescente. Delle 26 specie attualmente presenti a Cuba, 4 sono da considerarsi in pericolo di estinzione, 4 "vulnerabili", 12 "potenzialmente minacciate" e 6 "stabili". La maggior parte delle specie endemiche è in qualche misura minacciata. La deforestazione e l’alterazione delle cavità carsiche, che costituiscono un habitat

The Centaur Chariklo and its rings system from stellar occultations in 2017

Science.gov (United States)

Leiva, Rodrigo; Sicardy, Bruno; Camargo, Julio; Ortiz, Jose Luis; Berard, Diane; Desmars, Josselin; Chariklo Occultations Team; Rio Group; Lucky Star Occultation Team; Granada Occultation Team

2017-10-01

A stellar occultation in June 3, 2013 revealed the presence of a dense ring system around the Centaur object (10199) Chariklo (Braga-Ribas et al., Nature 2014). Subsequent analysis of occultation data and long-term photometric variations indicate that Chariklo's body is elongated (Leiva et al. 2017, submitted) and that the main ring exhibits significant longitudinal variations of the radial width (Bérard et al. 2017, in press). We report three multi-chord high-quality stellar occultation by Chariklo on April 9, 2017 and June 22, 2017 from Namibia, and July 23 2017 from South America. The analysis of this new data set is underway, but preliminary results are consistent with triaxial ellipsoidal models. From this analysis we will:-present refined models for the size and shape of Chariklo's main body andevaluate the heights and slopes of its topographic features.-give constraints on the longitudinal width variations of Chariklo's rings andexplore the possibility to obtain the rings apsidal precession rate.Chariklo's shape and topography have strong consequences on the dynamics of the rings through Lindblad-type resonances between mean motion of the ring particles and the spin of the main body, while the rings precession rate gives constraints on the dynamical oblateness of the main body.**Part of the research leading to these results has received funding from the European Research Council under the European Community’s H2020 (2014-2020/ ERC Grant Agreement n 669416 ”LUCKY STAR”).

Radio frequency system of the RIKEN ring cyclotron

International Nuclear Information System (INIS)

Fujisawa, T.; Ogiwara, K.; Kohara, S.; Oikawa, Y.; Yokoyama, I.; Nagase, M.; Takeshita, I.; Chiba, Y.; Kumata, Y.

1987-01-01

The radio-frequency(RF) system of the RIKEN ring cyclotron(K = 540) is required to work in a frequency range of 20 to 45 MHz and to generate the maximum acceleration voltage 250 kV. A new movable box type variable frequency resonator was designed for that purpose. The final amplifier is capable to deliver 300 kW. The resonators and the amplifiers have been installed at RIKEN and the performances are studied. The result shows the movable box type resonator and the power amplifier system satisfy the design aim. (author)

Digital closed orbit feedback system for the Advanced Photon Source storage ring

International Nuclear Information System (INIS)

Chung, Y.; Barr, D.; Decker, G.; Galayda, J.; Lenkszus, F.; Lumpkin, A.; Votaw, A.J.

1995-01-01

Closed orbit feedback for the Advanced Photon Source (APS) storage ring employs unified global an local feedback systems for stabilization of particle and photon beams based on digital signal processing (DSP). Hardware and software aspects of the system will be described. In particular, we will discuss global and local orbit feedback algorithms, PID (proportional, integral, and derivative) control algorithm. application of digital signal processing to compensate for vacuum chamber eddy current effects, resolution of the interaction between global and local systems through decoupling, self-correction of the local bump closure error, user interface through the APS control system, and system performance in the frequency and time domains. The system hardware, including the DSPS, is distributed in 20 VNE crates around the ring, and the entire feedback system runs synchronously at 4-kHz sampling frequency in order to achieve a correction bandwidth exceeding 100 Hz. The required data sharing between the global and local feedback systems is facilitated via the use of fiber-optically-networked reflective memories

An Alternative Derivation of the Energy Levels of the "Particle on a Ring" System

Science.gov (United States)

Vincent, Alan

1996-10-01

All acceptable wave functions must be continuous mathematical functions. This criterion limits the acceptable functions for a particle in a linear 1-dimensional box to sine functions. If, however, the linear box is bent round into a ring, acceptable wave functions are those which are continuous at the 'join'. On this model some acceptable linear functions become unacceptable for the ring and some unacceptable cosine functions become acceptable. This approach can be used to produce a straightforward derivation of the energy levels and wave functions of the particle on a ring. These simple wave mechanical systems can be used as models of linear and cyclic delocalised systems such as conjugated hydrocarbons or the benzene ring. The promotion energy of an electron can then be used to calculate the wavelength of absorption of uv light. The simple model gives results of the correct order of magnitude and shows that, as the chain length increases, the uv maximum moves to longer wavelengths, as found experimentally.

Soil-plant relation in Cuban sugar cane by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Diaz Riso, O.; Griffith Martinez, J.

1996-01-01

This paper shows the result of soil-plant relation in samples from Cuban sugar canes of different soil types and cane varieties, using the INAA from thermal reactor. The behaviour of minor and trace elements in sugar cane leaves is uniform and independent of sugar cane variety or type of soil. The soil-plant relation shows four principal groups of micro elements, according to their absorption by the plant

Decontamination of Cuban oysters using irradiation

Energy Technology Data Exchange (ETDEWEB)

Cisneros Despaigne, E; Leyva Castillo, V; Martinez, L L; Lara Ortiz, C [Instituto de Nutricion e Higiene de los Alimentos (Cuba); Castillo Rodriguez, E [Centro Nacional de Salud Animal (Cuba)

2001-04-01

Oysters (Crassostrea virginica) collected on the Cuban coast near Havana were examined for contamination with Vibrio cholerae and other potentially pathogenic Vibrio species. The strains thus isolated were characterized and identified to species following standard methods, and their radiation resistance (D{sub 10}) was determined in pure culture. The Vibrio species most often isolated were V. cholerae, V. parahaemolyticus and V. Alginolyticus. Representative cultures from each species were later used to inoculate shucked oysters to determine the optimal radiation dose that would ensure elimination of 10{sup 8} colony forming units (CFU)/g. The highest proportion of isolates were identified as Vibrio parahaemolyticus and V. algynoliticus. Non-O1 strains of Vibrio cholerae were isolated from 50% of samples, but no V. cholerae O1 was identified. D{sub 10} values calculated for the various strains were low in relation to those in the literature. The radiation dose for decontaminating heavily inoculated (10{sup 8} CFU/g) oysters was 1.2 kGy. (author)

Decontamination of Cuban oysters using irradiation

International Nuclear Information System (INIS)

Cisneros Despaigne, E.; Leyva Castillo, V.; Martinez, L.L.; Lara Ortiz, C.; Castillo Rodriguez, E.

2001-01-01

Oysters (Crassostrea virginica) collected on the Cuban coast near Havana were examined for contamination with Vibrio cholerae and other potentially pathogenic Vibrio species. The strains thus isolated were characterized and identified to species following standard methods, and their radiation resistance (D 10 ) was determined in pure culture. The Vibrio species most often isolated were V. cholerae, V. parahaemolyticus and V. Alginolyticus. Representative cultures from each species were later used to inoculate shucked oysters to determine the optimal radiation dose that would ensure elimination of 10 8 colony forming units (CFU)/g. The highest proportion of isolates were identified as Vibrio parahaemolyticus and V. algynoliticus. Non-O1 strains of Vibrio cholerae were isolated from 50% of samples, but no V. cholerae O1 was identified. D 10 values calculated for the various strains were low in relation to those in the literature. The radiation dose for decontaminating heavily inoculated (10 8 CFU/g) oysters was 1.2 kGy. (author)

The kicker magnet system for TRISTAN Accumulation Ring injection

International Nuclear Information System (INIS)

Sakamoto, Y.; Satoh, K.; Nakayama, H.

1994-12-01

The injection of electron beams to TRISTAN Accumulation Ring (AR) was started in November 1983 and the positron injection started in November 1985. For the injection of electron and positron beams to AR, the unique kicker system was developed. In the kicker power supply the charging to the main capacitor was done with the resonant charge system together with the auxiliary charging unit. The impedance matching circuit was added to the kicker magnet for getting the required current form with least reflecting oscillation. In this paper we report the performance of this kicker system. (author)

Systematic Search for Rings around Kepler Planet Candidates: Constraints on Ring Size and Occurrence Rate

Science.gov (United States)

Aizawa, Masataka; Masuda, Kento; Kawahara, Hajime; Suto, Yasushi

2018-05-01

We perform a systematic search for rings around 168 Kepler planet candidates with sufficient signal-to-noise ratios that are selected from all of the short-cadence data. We fit ringed and ringless models to their light curves and compare the fitting results to search for the signatures of planetary rings. First, we identify 29 tentative systems, for which the ringed models exhibit statistically significant improvement over the ringless models. The light curves of those systems are individually examined, but we are not able to identify any candidate that indicates evidence for rings. In turn, we find several mechanisms of false positives that would produce ringlike signals, and the null detection enables us to place upper limits on the size of the rings. Furthermore, assuming the tidal alignment between axes of the planetary rings and orbits, we conclude that the occurrence rate of rings larger than twice the planetary radius is less than 15%. Even though the majority of our targets are short-period planets, our null detection provides statistical and quantitative constraints on largely uncertain theoretical models of the origin, formation, and evolution of planetary rings.

Simulation of Small Wind Turbine Generation System Using Ring Winding Slotless PMSG by FEM

OpenAIRE

徳永, 翔平; 袈裟丸, 勝己; Tokunaga, Shohei; Kesamaru, Katsumi

2011-01-01

This paper describes a novel small wind turbine generation system with ring winding slotless PMSG. To reduce cogging torque, ring winding PM generator is used for a wind turbine generator. Using finite element analysis, the characteristics of slotless PMSGs are elucidated and the dynamic performance of the proposed system with MPPT control is represented. In this paper, the constant wind test and the quasi-natural wind test are conducted. The results of these tests indicate the proposed syste...

Comparison of Major Immunoglobulins Intrathecal Synthesis Patterns in Ecuadorian and Cuban Patients with Angiostrongyliasis

Science.gov (United States)

Padilla-Docal, Bárbara; Dorta-Contreras, Alberto J.; Moreira, Juan M.; Martini-Robles, Luiggi; Muzzio-Aroca, Jenny; Alarcón, Fernando; Magraner-Tarrau, María Esther; Bu-Coifiu-Fanego, Raisa

2011-01-01

Angiostrongylus cantonensis meningitis was first reported in Cuba in 1981, and it was recently reported in South America. The aim of this paper is to evaluate the intrathecal immunoglobulin synthesis patterns from Cuba's and Ecuador's patients with angiostrongyliasis; 8 Ecuadorian patients from two different outbreaks and 28 Cuban patients were studied. Simultaneous blood and cerebrospinal fluid simples were taken. Immunoglobulin (Ig) A, IgM, IgG, and albumin were quantified by radial immunodiffusion. Corresponding Reibergrams were applied. A three-Ig pattern was the most frequent in the two groups, but IgM was presented in all Ecuadorian young mature patients; however, in the Cuban children, only 12 of 28 patients had intrathecal IgM, but about 90% had an IgA and IgG synthesis at time of later puncture. This indicates that, with a larger amount of parasites ingested, clinical symptoms are more severe, and a higher frequency of intrathecal IgM synthesis could be observed. This is discussed as a similarity with the intrathecal IgM synthesis in African trypanosomiasis. PMID:21363978

Simulation of the control system for the KEK main ring power supply-II

International Nuclear Information System (INIS)

Kabe, Atsushi; Sato, Hikaru; Masuda, Masayoshi; Takeda, Masahiro; Nakano, Michio

1977-05-01

The tracking error between the magnetic field of the bending magnets and that of the quadrupole magnets is a very important problem of the KEK main ring power supply. Tacking performance is simulated using DDS (Digital Dynamics Simulator) in cases of 8 GeV and 12 GeV operation of the KEK main ring. The results of simulation coincide with the data of actual system. (auth.)

Cryogenic systems for large superconducting accelerators/storage rings

International Nuclear Information System (INIS)

Brown, D.P.

1981-01-01

Particle accelerators and storage rings which utilize superconducting magnets have presented cryogenic system designers, as well as magnet designers, with many new challenges. When such accelerators were first proposed, little operational experience existed to guide the design. Two superconducting accelerators, complete with cryogenic systems, have been designed and are now under construction. These are the Fermilab Doubler Project and the Brookhaven National Laboratory ISABELLE Project. The cryogenic systems which developed at these two laboratories share many common characteristics, especially as compared to earlier cryogenic systems. Because of this commonality, these characteristics can be reasonably taken as also being representative of future systems. There are other areas in which the two systems are dissimilar. In those areas, it is not possible to state which, if either, will be chosen by future designers. Some of the design parameters for the two systems are given

Topological ring currents in the "empty" ring of benzo-annelated perylenes.

Science.gov (United States)

Dickens, Timothy K; Mallion, Roger B

2011-01-27

Cyclic conjugation in benzo-annelated perylenes is examined by means of the topological π-electron ring currents calculated for each of their constituent rings, in a study that is an exact analogy of a recent investigation by Gutman et al. based on energy-effect values for the corresponding rings in each of these structures. "Classical" approaches, such as Kekulé structures, Clar "sextet" formulas, and circuits of conjugation, predict that the central ring in perylene is "empty" and thus contributes negligibly to cyclic conjugation. However, conclusions from the present calculations of topological ring currents agree remarkably with those arising from the earlier study involving energy-effect values in that, contrary to what would be predicted from the classical approaches, rings annelated in an angular fashion relative to the central ring of these perylene structures materially increase the extent of that ring's involvement in cyclic conjugation. It is suggested that such close quantitative agreement between the predictions of these two superficially very different indices (energy effect and topological ring current) might be due to the fact that, ultimately, both depend, albeit in ostensibly quite different ways, only on an adjacency matrix that contains information about the carbon-carbon connectivity of the conjugated system in question.

An analog RF gap voltage regulation system for the Advanced Photon Source storage ring

International Nuclear Information System (INIS)

Horan, D.

1999-01-01

An analog rf gap voltage regulation system has been designed and built at Argonne National Laboratory to maintain constant total storage ring rf gap voltage, independent of beam loading and cavity tuning effects. The design uses feedback control of the klystron mod-anode voltage to vary the amount of rf power fed to the storage ring cavities. The system consists of two independent feedback loops, each regulating the combined rf gap voltages of eight storage ring cavities by varying the output power of either one or two rf stations, depending on the mode of operation. It provides full operator control and permissive logic to permit feedback control of the rf system output power only if proper conditions are met. The feedback system uses envelope-detected cavity field probe outputs as the feedback signal. Two different methods of combining the individual field probe signals were used to generate a relative DC level representing one-half of the total storage ring rf voltage, an envelope-detected vector sum of the field probe rf signals, and the DC sum of individual field probe envelope detector outputs. The merits of both methods are discussed. The klystron high-voltage power supply (HVPS) units are fitted with an analog interface for external control of the mod-anode voltage level, using a four-quadrant analog multiplier to modulate the HVPS mod-anode voltage regulator set-point in response to feedback system commands

Castro’s Ploy-America’s Dilemma: The 1980 Cuban Boatlift

Science.gov (United States)

1988-12-01

Even the music in Cuba had become politicized- few romantic songs were played. Mercedes and her family liked to go to the beach for recreation. Because...of religious beliefs through scientific materialistic propaganda."’ 2-5 The government employed such harassing tech- niques as blaring loud music from...dollars, two blue-topped Cuban government turismo boats quickly appeared in the harbor to sell goods to the woaters. Ham sandwiches cost $i one day, $3

Corporate Social Responsibility: a proposal for its assessment in Cuban hotel facilities

Directory of Open Access Journals (Sweden)

Yusmelys Ferrales-Arias

2017-12-01

Full Text Available The present article, after addressing the fundamental elements that characterize the corporate social responsibility approach, proposes a procedure for its evaluation in Cuban hotel facilities through the use of instruments based on indicators developed for this purpose. The study focuses on measuring the degree of social responsibility and the level of responsible performance that allows the installation management to properly align the practices of social responsibility with the installation strategy.

Structural and magnetic characterization of three tetranuclear Cu(II) complexes with face-sharing-dicubane/double-open-cubane like core framework

Energy Technology Data Exchange (ETDEWEB)

Paul, Aparup [Department of Chemistry and Chemical Technology, Vidyasagar University, Midnapore 721102, West Bengal (India); Bertolasi, Valerio [Dipartimento di Scienze Chimiche e Farmaceutiche, Centro di Strutturistica Diffrattometrica, Università di Ferrara, Via L. Borsari, 46, 44100 Ferrara (Italy); Figuerola, Albert [Departament de Química Inorgànica i Orgànica (Secció de Química Inorgànica) and Institut de Nanociència i Nanotecnologia (IN2UB), Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona (Spain); Manna, Subal Chandra, E-mail: scmanna@mail.vidyasagar.ac.in [Department of Chemistry and Chemical Technology, Vidyasagar University, Midnapore 721102, West Bengal (India)

2017-05-15

Three novel tetranuclear copper(II) complexes namely [Cu{sub 4}(L{sup 1}){sub 4}]∙2(dmf) (1), [Cu{sub 4}(L{sup 1}){sub 4}] (2) and [Cu{sub 4}(L{sup 2}){sub 2}(HL{sup 2}){sub 2}(H{sub 2}O){sub 2}]∙2(ClO{sub 4})·6(H{sub 2}O) (3) (H{sub 2}L{sup 1}, (E)−2-((1-hydroxybutan-2-ylimino)methyl)phenol; H{sub 2}L{sup 2}, (E)−2-((1-hydroxybutan-2-ylimino)methyl)−6-methoxyphenol)) were synthesized from the self-assembly of copper(II) perchlorate and the tridentate Schiff base ligands. The structural determination reveals that crystallizes in the monoclinic system with space group C2/c, whereas both the and crystallize in the triclinic system with space group P-1. and possess face-sharing dicubane core, on the other hand complex 3 has double open cubane core structure. The copper(II) ions in the cubane core are in distorted square planar geometries, and weak π…π and C–H…π interactions lead to formation of a 2D supramolecular architecture for and . At room temperature and , exhibit fluorescence with a quantum yield (Φ{sub s}) of 0.47, 0.49 and 0.38, respectively. Variable temperature magnetic susceptibility measurements in the range 2–300 K indicate an overall weak antiferromagnetic exchange coupling in all complexes. The PHI program was used to study their magnetic behaviour. In agreement with their face-sharing dicubane structure, a Hamiltonian of the type H =– J{sub 1}(S{sub 1}S{sub 2}+S{sub 1}S{sub 2’}+S{sub 1'}S{sub 2}+S{sub 1'}S{sub 2’}) – J{sub 2}S{sub 1}S{sub 1’}, where S{sub 1} = S{sub 1’} = S{sub 2} = S{sub 2’} = S{sub Cu} =1/2, was used for studying and . Simulations performed suggest magnetic exchange constants with values close to J{sub 1} =−20 cm{sup −1} and J{sub 2} =0 cm{sup -1} for these complexes. On the other hand, the spin Hamiltonian H =– J{sub 1}(S{sub 1}S{sub 4}+S{sub 2}S{sub 3}) – J{sub 2}(S{sub 1}S{sub 3}+S{sub 2}S{sub 4}) – J{sub 3}S{sub 1}S{sub 2}, where S{sub 1} = S{sub 2} = S{sub 3} = S{sub 4

PF-KO system for single bunch mode operation of a storage ring

International Nuclear Information System (INIS)

Ohgaki, H.; Sugiyama, S.; Mikado, T.; Chiwaki, M.; Yamada, K.; Suzuki, R.; Sei, N.; Noguchi, T.; Yamazaki, T.

1994-01-01

A new RF-KO (RF knockout) system for the single bunch mode operation of a storage ring has been developed. The knockout signal is modulated by the sum signal of the RF acceleration frequency of the storage ring and a bunch selection signal. We do not need any special device or a timing unit with this method. We obtain a high purity of bunch structure in a short knock out time. The single bunch impurity of 0.2% has been achieved. (author)

Environmental Management in the Process of Purification of Cuban Furfural in the Chemical Bioactive Center Plant

Directory of Open Access Journals (Sweden)

Ing. Liset Rodríguez-Machín

2016-02-01

Full Text Available It is necessary to establish in the installed equipment, operating conditions and quality specifications in the purification of furfural produced in Cuba. To do this some literature review and experiments are carried out. The approved batches by the quality control are quantified as well as the heat and evaporation losses and the impact on workers health. Energy management is performed by identifying electricity as the energy source of higher consumption. Some measures are applied like coating the evaporator portions that are required together with condenser modification and improvement of the room ventilation. As a result it was shown that it is possible to purify the Cuban furfural in the installed equipment, the process efficiency increases in 5,5 %, the evaporation losses decrease and non-acceptance by quality control drops. If the imported furfural is replaced by the Cuban are saved about 39 000 • per year production.

Nonlinear analysis of ring oscillator circuits

KAUST Repository

Ge, Xiaoqing

2010-06-01

Using nonlinear systems techniques, we analyze the stability properties and synchronization conditions for ring oscillator circuits, which are essential building blocks in digital systems. By making use of its cyclic structure, we investigate local and global stability properties of an n-stage ring oscillator. We present a sufficient condition for global asymptotic stability of the origin and obtain necessity if the ring oscillator consists of identical inverter elements. We then give a synchronization condition for identical interconnected ring oscillators.

Nonlinear analysis of ring oscillator circuits

KAUST Repository

Ge, Xiaoqing; Arcak, Murat; Salama, Khaled N.

2010-01-01

Using nonlinear systems techniques, we analyze the stability properties and synchronization conditions for ring oscillator circuits, which are essential building blocks in digital systems. By making use of its cyclic structure, we investigate local and global stability properties of an n-stage ring oscillator. We present a sufficient condition for global asymptotic stability of the origin and obtain necessity if the ring oscillator consists of identical inverter elements. We then give a synchronization condition for identical interconnected ring oscillators.

Variable diameter CO2 laser ring-cutting system adapted to a zoom microscope for applications on polymer tapes.

Science.gov (United States)

Förster, Erik; Bohnert, Patrick; Kraus, Matthias; Kilper, Roland; Müller, Ute; Buchmann, Martin; Brunner, Robert

2016-11-20

This paper presents the conception and implementation of a variable diameter ring-cutting system for a CO2 laser with a working wavelength of 10.6 μm. The laser-cutting system is adapted to an observation zoom microscope for combined use and is applicable for the extraction of small circular areas from polymer films, such as forensic adhesive tapes in a single shot. As an important characteristic for our application, the variable diameter ring-cutting system provides telecentricity in the target area. Ring diameters are continuously tunable between 500 μm and 2 mm. A minimum width of less than 20 μm was found for the ring profile edge. The basic characteristics of the system, including telecentricity, were experimentally evaluated and demonstrated by cutting experiments on different polymer tapes and further exemplary samples.

A Study of Storage Ring Requirements for an Explosive Detection System Using NRA Method

CERN Document Server

Wang, Tai-Sen

2005-01-01

The technical feasibility of an explosives detection system based on the nuclear resonance absorption (NRA) of gamma rays in nitrogen-rich materials was demonstrated at Los Alamos National Laboratory (LANL) in 1993 by using an RFQ proton accelerator and a tomographic imaging prototype.* The study is being continued recently to examine deployment of such an active interrogation system in realistic scenarios. The approach is to use a cyclotron and electron-cooling-equipped storage rings(s) to provide the high quality and high current proton beam needed in a practical application. In this work, we investigate the storage ring requirements for a variant of the airport luggage inspection system considered in the earlier LANL experiments. Estimations are carried out based on the required inspection throughput, the gamma ray yield, the proton beam emittance growth due to scattering with the photon-production target, beam current limit in the storage ring, and the electron cooling rate. Studies using scaling and reas...

Vibration characteristics of two-stage planetary transmission system with thin-walled ring gear on elastic supports

Science.gov (United States)

Li, JianYing; Hu, QingChun; Zong, ChangFu; Zhu, TianJun; Zhang, ZeXing

2018-03-01

A dual-clutch and dual-speed planetary gears mechanism of a hybrid car coupled-system is taken as research subject, in which the ring gear of planet set II is a thin-walled structure and the clutch friction plates of planet set II are used as its elastic supports. Based on the lumped parameter-rigid elastic coupled dynamic model of two-stage planetary transmission system with thin-walled ring gear on elastic supports, the motion differential equations are established and the dynamic responses are solved by the Runge-Kutta method considering each stage internal and external time-varying mesh stiffness. The vibration displacements of each stage ring gear have been affected differently in time-domain, the translational vibration displacement of the ring gear of planet set I are obviously more than the torsional vibration displacement, but it is opposite for the ring gear of planet set II; The translational and torsional vibration responses of each stage ring gear arrive the peak in low-frequency. The analysis results of this paper can enrich the theoretical research of multistage planetary transmission and provide guidance for dynamic design.

Electro-optical hybrid slip ring

Science.gov (United States)

Hong, En

2005-11-01

The slip ring is a rotary electrical interface, collector, swivel or rotary joint. It is a physical system that can perform continuous data transfer and data exchange between a stationary and a rotating structure. A slip ring is generally used to transfer data or power from an unrestrained, continuously rotating electro-mechanical system in real-time, thereby simplifying operations and eliminating damage-prone wires dangling from moving joints. Slip rings are widely used for testing, evaluating, developing and improving various technical equipment and facilities with rotating parts. They are widely used in industry, especially in manufacturing industries employing turbo machinery, as in aviation, shipbuilding, aerospace, defense, and in precise facilities having rotating parts such as medical Computerized Tomography (CT) and MRI scanners and so forth. Therefore, any improvement in slip ring technology can impact large markets. Research and development in this field will have broad prospects long into the future. The goal in developing the current slip ring technology is to improve and increase the reliability, stability, anti-interference, and high data fidelity between rotating and stationary structures. Up to now, there have been numerous approaches used for signal and data transfer utilizing a slip ring such as metal contacts, wires, radio transmission, and even liquid media. However, all suffer from drawbacks such as data transfer speed limitations, reliability, stability, electro-magnetic interference and durability. The purpose of the current research is to break through these basic limitations using an optical solution, thereby improving performance in current slip ring applications. This dissertation introduces a novel Electro-Optical Hybrid Slip Ring technology, which makes "through the air" digital-optical communication between stationary and rotating systems a reality with high data transfer speed, better reliability and low interference susceptibility

Founded: Genetic Reconstruction of Lineage Diversity and Kinship Informs Ex situ Conservation of Cuban Amazon Parrots (Amazona leucocephala).

Science.gov (United States)

Milián-García, Yoamel; Jensen, Evelyn L; Madsen, Jeanette; Álvarez Alonso, Suleiky; Serrano Rodríguez, Aryamne; Espinosa López, Georgina; Russello, Michael A

2015-01-01

Captive breeding is a widespread conservation strategy, yet such programs rarely include empirical genetic data for assessing management assumptions and meeting conservation goals. Cuban Amazon parrots (Amazona leucocephala) are considered vulnerable, and multiple on-island captive populations have been established from wild-caught and confiscated individuals of unknown ancestry. Here, we used mitochondrial haplotypic and nuclear genotypic data at 9 microsatellite loci to quantify the extent and distribution of genetic variation within and among captive populations in Zapata Swamp and Managua, Cuba, and to estimate kinship among breeders (n = 88). Using Bayesian clustering analysis, we detected 2 distinct clusters within the Zapata population, one of which was shared with Managua. Individuals from the cluster unique to Zapata possessed mitochondrial haplotypes with affinities to Cuban subspecies (A. l. leucocephala, A. l. palmarum); the shared cluster was similar, but also included haplotypes closely related to the subspecies restricted to Cayman Brac (A. l. hesterna). Overall mean kinship was low within each captive population (-0.026 to -0.012), with 19 and 11 recommended breeding pairs in Zapata and Managua, respectively, ranked according to mean kinship and informed by molecular sexing. Our results highlight the importance of understanding population history within ex situ management programs, while providing genetic information to directly inform Cuban parrot conservation. © The American Genetic Association 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Tunable optical analog to electromagnetically induced transparency in graphene-ring resonators system.

Science.gov (United States)

Wang, Yonghua; Xue, Chenyang; Zhang, Zengxing; Zheng, Hua; Zhang, Wendong; Yan, Shubin

2016-12-12

The analogue of electromagnetically induced transparency in optical ways has shown great potential in optical delay and quantum-information technology due to its flexible design and easy implementation. The chief drawback for these devices is the bad tunability. Here we demonstrate a tunable optical transparency system formed by graphene-silicon microrings which could control the transparent window by electro-optical means. The device consists of cascaded coupled ring resonators and a graphene/graphene capacitor which integrated on one of the rings. By tuning the Fermi level of the graphene sheets, we can modulate the round-trip ring loss so that the transparency window can be dynamically tuned. The results provide a new method for the manipulation and transmission of light in highly integrated optical circuits and quantum information storage devices.

Los Alamos Proton Storage Ring (PSR) injection deflector system

International Nuclear Information System (INIS)

Jason, A.j.; Higgins, E.F.; Koelle, A.R.

1983-01-01

We describe a pulsed magnetic deflector system planned for the injection system of the PSR. Two sets of magnets, appropriately placed in the optical systems of both the ring and the injection transport line, provide control of the rate at which particles are injected into a given portion of transverse phase space and limit the interaction of stored beam with the injection stripping foil. High-current modulators that produce relatively complex waveforms are required for this purpose. Solid-state drivers using direct feedback to produce the necessary waveforms are discussed as replacements for the more conventional high-voltage tube technology

Neutron activation analysis of final molasses from cuban sugar industry

International Nuclear Information System (INIS)

Griffith, J.; Gonzalez, E.; Rosenberg, R.J.; Diaz-Rizo, O.

1996-01-01

Thermal and epithermal non-destructive activation analyses have been performed on samples of final molasses from 14 different sugar factories , covering the most important regions in Cuba. From the first measurement after irradiation at the Triga Mark reactor (VTT), the concentration of more than 15 elements is reported. The almost constant elemental composition shows that they can be used equally for different purposes as animal foodstuff and for the manufacture of biotechnological products. This work is part of a research project developed in order to establish a complete characterization of Cuban sugar molasses. (author). 7 refs., 2 tabs

The Cuban Missile Crisis of 1962: A Case Study of the Tailored Use of Instruments of National Power

National Research Council Canada - National Science Library

Charney, Sean S

2008-01-01

President Kennedy and the EXCOM were able to achieve foreign policy success during the Cuban Missile Crisis because of their ability to tailor the pertinent IOPs and implement them to reach a desired...

Immobilization of radioactive waste through cementation using Cuban zeolitic rock as additive

International Nuclear Information System (INIS)

Chales Suarez, G.; Castillo Gomez, R.

1997-01-01

The cementation of both simulated and real low level aqueous wastes using Cuban zeolite as additive is described. Mechanical characteristics and leach testing of the cemented waste forms has been studied. The results obtained have shown that the presence of zeolite in the cemented waste for reduces considerably the leach rates of Cs and Co and moreover, mechanical characteristics (set time and compressive strength) are better when compared with direct cementation of aqueous wastes. (author). 13 refs, 8 tabs

Modelling a Java Ring based implementation of an N-Count payment system

NARCIS (Netherlands)

Revill, J.D.; Hartel, Pieter H.

N-Count is a system for offline value transfer. A prototype of an N-Count payment system has been designed, and it has been implemented in Java. We have used the Java Ring with the Java Card API as a secure device. The system has also been modelled using the Spin model checker. The combined

Vacuum system for the NIJI-III compact storage ring

International Nuclear Information System (INIS)

Miura, F.; Tsutsui, Y.; Takada, H.

1990-01-01

The NIJI-III is a compact storage ring measuring about 15 m in circumference with four superconducting bending magnets. It is under development as a synchrotron light source for X-ray lithography with a stored beam current of 200 mA at a stored beam current of 200 mA at a stored energy level of 615 MeV. The vacuum system is designed to attain a pressure of less than 1 x 10 -9 Torr at beam storage. The compact ring design makes it difficult to install a large number of pumps able to satisfy the required pumping speed. For the purpose of realizing a high pumping speed, a cryopump as a result of cooling the superconducting magnet duct wall to the liquid helium (LHe) temperature is adopted, as a result the total pumping speed to 2.8 x 10 4 l/s is obtained. (author)

Industrial property for science’s management, technology and innovation in Cuban State companies

OpenAIRE

Contreras Villavicencio, Dulce María; Suárez Gutiérrez, Evelio; Moreno Cruz, Marta Milagros; Correa Álvarez, Pascual

2017-01-01

The paper synthesizes some research on industrial property aspects from the socio-legal perspective and financial accounting. Its focus to the socialist state enterprise adaptation in his economic fact, social and environmental responsibility as a fundamental Cuban model reach, competitiveness and high performance in socialist state enterprise. It outlines criteria on the ordering and implementation of industrial property through the management of science and technology, protection and dissem...

Historical personalities of the Cuban education. A reflection necesary

Directory of Open Access Journals (Sweden)

Yordan Nápoles-Ramírez

2017-04-01

Full Text Available Along the History of the Cuban education, the teaching and the learning of the life and work of the historical personalities has constituted a priority. However, the tendency has prevailed to alone to approach in the different teaching levels the historical personalities from a political-military focus, without conceiving an integrative treatment that embraces other spheres of the social activity. Equal limitations exist in reconstructing the historical context where the same ones were developed and to analyze their narrow one with the diverse social sectors that accompanied her. The present article seeks to demonstrate the necessity to transform the treatment of the historical personalities at the present time. 

78 FR 9573 - Delegation of Authority To Suspend the Provisions of Title III of the Cuban Liberty and...

Science.gov (United States)

2013-02-08

... Authority To Suspend the Provisions of Title III of the Cuban Liberty and Democratic Solidarity (LIBERTAD... Liberty and Democratic Solidarity (LIBERTAD) Act of 1996 (Public Law 104-114; 22 U.S.C. 6021-6091), as...

Token ring technology report

CERN Document Server

2013-01-01

Please note this is a Short Discount publication. This report provides an overview of the IBM Token-Ring technology and products built by IBM and compatible vendors. It consists of two sections: 1. A summary of the design trade-offs for the IBM Token-Ring. 2. A summary of the products of the major token-ring compatible vendors broken down by adapters and components, wiring systems, testing, and new chip technology.

Self-gravitation in Saturn's rings

International Nuclear Information System (INIS)

Salo, H.; Lukkari, J.

1982-01-01

In a ring-shaped collisional system self-gravitation reduces the equilibrium values of the geometric and optical thickness. In Saturn's rings both effects are appreciable. The previously found discrepancy between the calculated profile and the observed profile of the rings is chiefly caused by the omission of self-gravitation. (Auth.)

Digital closed orbit feedback system for the advanced photon source storage ring

International Nuclear Information System (INIS)

Chung, Y.; Barr, D.; Decker, G.

1995-01-01

The Advanced Photon Source (APS) is a dedicated third-generation synchrotron light source with a nominal energy of 7 GeV and a circumference of 1104 m. The closed orbit feedback system for the APS storage ring employs unified global and local feedback systems for stabilization of particle and photon beams based on digital signal processing (DSP). Hardware and software aspects of the system will be described in this paper. In particular, we will discuss global and local orbit feedback algorithms, PID (proportional, integral, and derivative) control algorithm, application of digital signal processing to compensate for vacuum chamber eddy current effects, resolution of the interaction between global and local systems through decoupling, self-correction of the local bump closure error, user interface through the APS control system, and system performance in the frequency and time domains. The system hardware including the DSPs is distributed in 20 VME crates around the ring, and the entire feedback system runs synchronously at 4-kHz sampling frequency in order to achieve a correction bandwidth exceeding 100 Hz. The required data sharing between the global and local feedback systems is facilitated via the use of fiber-optically-networked reflective memories

Embedding the dynamics of a single delay system into a feed-forward ring.

Science.gov (United States)

Klinshov, Vladimir; Shchapin, Dmitry; Yanchuk, Serhiy; Wolfrum, Matthias; D'Huys, Otti; Nekorkin, Vladimir

2017-10-01

We investigate the relation between the dynamics of a single oscillator with delayed self-feedback and a feed-forward ring of such oscillators, where each unit is coupled to its next neighbor in the same way as in the self-feedback case. We show that periodic solutions of the delayed oscillator give rise to families of rotating waves with different wave numbers in the corresponding ring. In particular, if for the single oscillator the periodic solution is resonant to the delay, it can be embedded into a ring with instantaneous couplings. We discover several cases where the stability of a periodic solution for the single unit can be related to the stability of the corresponding rotating wave in the ring. As a specific example, we demonstrate how the complex bifurcation scenario of simultaneously emerging multijittering solutions can be transferred from a single oscillator with delayed pulse feedback to multijittering rotating waves in a sufficiently large ring of oscillators with instantaneous pulse coupling. Finally, we present an experimental realization of this dynamical phenomenon in a system of coupled electronic circuits of FitzHugh-Nagumo type.

Beam monitors and transverse feedback system of TRISTAN Main Ring

International Nuclear Information System (INIS)

Ieiri, T.; Ishii, H.; Kishiro, J.; Mizumachi, Y.; Mori, K.; Nakajima, K.; Ogata, A.; Shintake, T.; Tejima, M.

1987-01-01

The construction of 30 GeV TRISTAN Main Ring (MR) started in 1983 soon after the commissioning of 8 GeV Accumulation Ring (AR). The authors prepared 392 position monitors, 6 synchrotron radiation monitors, 9 screen monitors, 2 DCCT's, 3 scrapers, 12 bunch monitors, transverse feedback systems for two beams and DC separators. Since the required monitoring devices of AR and MR are almost the same, the experiences in AR were very useful in the design of MR monitors. However, machine parameters of two rings are very different and the authors had to review the performance of each item. From the monitor point of view the most important is the difference of revolution frequency; 794.6 kHz for AR and 99.33 kHz for MR. This means that average beam current of MR is 1/8 as small as AR current with the same bunch number and intensity. Therefore, the sensitivity of each monitor must be better in MR. The second difference is that MR should be used as a collider from the beginning. Therefore they must prepare for multi-beam and multi-bunch operation

Response of booster dose of cuban recombinant hepatitis-B vaccine in nonresponder and hyporesponder children

International Nuclear Information System (INIS)

Dahifar, H.; Mousavi, F.; Ghorbani, A.

2007-01-01

Acute hepatitis B infection can debilitate a patient for weeks and occasionally has a fatal outcome, while chronic infection is a major threat to the individual. To assess response of nonresponder and hyporesponder children to booster dose of Cuban recombinant hepatitis B vaccine. An interventional, descriptive study has been conducted on children who had been immunized with Cuban recombinant Hepatitis B vaccine and their antibody titers were <10mIU/ml (nonresponder) and 10-100mIU/ml (hyporesponder) administered booster dose of the same vaccine in their Deltoid muscles. The response of 141 children with the mean age of 1.9 years to booster dose of vaccine were 94.3% and 100% vaccines with the first and second booster dose of vaccination respectively. The anti-HBs titer in nonresponders and hyporesponders were 468+-346 and 783+-346mIU/ml respectively with significant differences between two groups (P=0.001). This study demonstrate moderately increase antibody production in the majority of vaccines with single supplementary vaccine. (author)

Concise copper-catalyzed synthesis of tricyclic biaryl ether-linked aza-heterocyclic ring systems.

Science.gov (United States)

Mestichelli, Paola; Scott, Matthew J; Galloway, Warren R J D; Selwyn, Jamie; Parker, Jeremy S; Spring, David R

2013-11-01

A new method for the synthesis of tricyclic biaryl ether-linked ring systems incorporating seven-, eight-, and nine-membered ring amines is presented. In the presence of catalytic quantities of copper(I), readily accessible acyclic precursors undergo an intramolecular carbon-oxygen bond-forming reaction facilitated by a "templating" chelating nitrogen atom. The methodology displays a broad substrate scope, is practical, and generates rare and biologically interesting tricyclic heteroaromatic products that are difficult to access by other means.

Quantum correlations in a bipartite multiqubit spin ring system

International Nuclear Information System (INIS)

Doronin, S I; Fel’dman, E B; Kuznetsova, E I

2015-01-01

We consider a spin ring with an arbitrary number of spins on the ring and one spin in its center in a strong external magnetic field. The spins on the ring are connected by the secular dipole–dipole interactions and interact with the central spin through the Heisenberg zz-interaction. We show that the quantum discord, describing quantum correlations between the ring and the central spin, can be obtained analytically for an arbitrary number of the spins in the high-temperature approximation. We demonstrate the evolution of quantum correlations at different numbers of the spins. The contributions of longitudinal and transversal spin interactions to the quantum discord are discussed. (paper)

Contribution gives the cosmic radiation to the doses for exhibition to the natural radiation in the Cuban population

International Nuclear Information System (INIS)

Tomas Zerquera, J.; Peres Sanchez, D.; Prendes Alonso, M

1998-01-01

With the objective to specify the preponderant contribution the cosmic component the radiation in the dose that the Cuban population receives you carries out a program she gives mensurations she gives this component in the whole country

Photometric Analysis of the Jovian Ring System and Modeling of Ring Origin and Evolution

Science.gov (United States)

Esposito, L. W.

2003-01-01

We have successfully completed the work described in our proposal. The work supported by this grant resulted in the publication of the following paper: Brooks, S. M., L. W. Esposito, M. R. Showalter, and H. B. Throop. 2002. The size distribution of Jupiter's main ring from Galileo imaging and spectroscopy. Icarus, in press. This was also the major part of Dr. Shawn Brooks PhD dissertation. Dr. Brooks gave oral presentations on this work at the Lunar and Planetary Conference, the annual meetings of the Division for Planetary Sciences of the American Astronomical Society, the annual meetings of the European Geophysical Society, the international Jupiter Conference in Boulder, the Jupiter after Galileo and Cassini Conference in Lisbon and to the Working Group in Non-Linear Dynamics in Potsdam, Germany. This work was reviewed in: Esposito, L. W. 2002. Planetary rings. Rep. hog. Phys. 65, 1741-1783. Planetary rings. LASP reprint 874. Online at http://stacks.iop.org/RoPP/65/1741. Dr. Esposito gave presentations at schools and over the internet on the results of this work. Dr. Brooks lectured in undergraduate and graduate classes on Jupiter's rings, and on the meaning of his research. In August 2003, Dr. Shawn Brooks received the Phd degree from the University of Colorado in Astrophysical and Planetary Sciences.

Linear and nonlinear optical susceptibilities in a laterally coupled quantum-dot–quantum-ring system

International Nuclear Information System (INIS)

Zeng, Zaiping; Garoufalis, Christos S.; Baskoutas, Sotirios

2014-01-01

Linear and nonlinear optical susceptibilities in a laterally coupled quantum-dot–quantum-ring system have been theoretically studied. In general, we find that the structure parameters of the coupled system significantly affect the optical susceptibilities. The enhancement of the coupling effects between the dot and ring is found to increase considerably the optical susceptibilities and redshift drastically the transition energies. Comparing to the linear susceptibility, the nonlinear optical susceptibility is found to be more sensitive to the variation of the structure parameters. A comprehensive analysis of the electron probability density movement with respect to the modification of the structure parameters is provided, which offers a unique perspective of the ground-state localization. - Highlights: • Optical susceptibilities in a quantum-dot–quantum-ring system are studied. • The structure parameters significantly affect the optical susceptibilities. • The enhancement of the coupling effects increases the optical susceptibilities. • The nonlinear susceptibility is more sensitive to the change in structure parameters. • A comprehensive analysis of the electron probability density movement is provided

Explicitly-correlated ring-coupled-cluster-doubles theory: Including exchange for computations on closed-shell systems

Energy Technology Data Exchange (ETDEWEB)

Hehn, Anna-Sophia; Holzer, Christof; Klopper, Wim, E-mail: klopper@kit.edu

2016-11-10

Highlights: • Ring-coupled-cluster-doubles approach now implemented with exchange terms. • Ring-coupled-cluster-doubles approach now implemented with F12 functions. • Szabo–Ostlund scheme (SO2) implemented for use in SAPT. • Fast convergence to the limit of a complete basis. • Implementation in the TURBOMOLE program system. - Abstract: Random-phase-approximation (RPA) methods have proven to be powerful tools in electronic-structure theory, being non-empirical, computationally efficient and broadly applicable to a variety of molecular systems including small-gap systems, transition-metal compounds and dispersion-dominated complexes. Applications are however hindered due to the slow basis-set convergence of the electron-correlation energy with the one-electron basis. As a remedy, we present approximate explicitly-correlated RPA approaches based on the ring-coupled-cluster-doubles formulation including exchange contributions. Test calculations demonstrate that the basis-set convergence of correlation energies is drastically accelerated through the explicitly-correlated approach, reaching 99% of the basis-set limit with triple-zeta basis sets. When implemented in close analogy to early work by Szabo and Ostlund [36], the new explicitly-correlated ring-coupled-cluster-doubles approach including exchange has the perspective to become a valuable tool in the framework of symmetry-adapted perturbation theory (SAPT) for the computation of dispersion energies of molecular complexes of weakly interacting closed-shell systems.

The fluid systems for the SLD Cherenkov ring imaging detector

International Nuclear Information System (INIS)

Abe, K.; Hasegawa, K.; Hasegawa, Y.; Iwasaki, Y.; Suekane, F.; Yuta, H.; Baird, K.; Jacques, P.; Kalelkar, M.; Plano, R.; Stamer, P.; Word, G.; Bean, A.; Caldwell, D.O.; Duboscq, J.; Huber, J.; Lu, A.; Mathys, L.; McHugh, S.; Yellin, S.; Ben-David, R.; Manly, S.; Snyder, J.; Turk, J.; Cavalli-Sforza, M.; Coyle, P.; Coyne, D.; Gagnon, P.; Liu, X.; Schneider, M.; Williams, D.A.; Coller, J.; Shank, J.T.; Whitaker, J.S.; d'Oliveira, A.; Johnson, R.A.; Martinez, J.; Nussbaum, M.; Santha, A.K.S.; Sokoloff, M.D.; Stockdale, I.; Wilson, R.J.

1992-10-01

We describe the design and operation of the fluid delivery, monitor and control systems for the SLD barrel Cherenkov Ring Imaging Detector (CRID). The systems deliver drift gas (C 2 H 6 + TMAE), radiator gas (C 5 F 12 + N 2 ) and radiator liquid (C 6 F 14 ). Measured critical quantities such as electron lifetime in the drift gas and ultra-violet (UV) transparencies of the radiator fluids, together with the operational experience, are also reported

Rf systems for high-energy e/sup /minus//e/sup /plus// storage rings

International Nuclear Information System (INIS)

Allen, M.A.; Wilson, P.B.

1974-01-01

Electron or positron beams in a storage ring radiate electromagnetic energy at a rate proportional to the fourth power of the recirculating energy, and this loss must be supplied by an rf system. Furthermore, a substantial overvoltage is required to contain the stored beam against losses due to quantum fluctuations in the emitted photons. As an example, an improvement program, SPEAR II, is now underway to increase the energy of the SPEAR ring to 4.5 GeV. At this energy, the radiation loss per turn is 2.8 MeV, and to maintain a reasonable lifetime against quantum fluctuations, a peak voltage of 7.5 MeV is required. Thus, the SPEAR II rf system is similar to a continuously-operating 7.5 MeV linear accelerator. Furthermore, the available straight-section space in the ring which is suitable for containing the accelerating structures is limited, and this means that a cavity design must be sought with a high shunt impedance per losses will be held to a reasonable level. In the case of SPEAR, about 9 meters of straight section space is available for accelerating cavities, requiring a gradient of close to 1 MV per meter. The PEP 15-GeV ring would require peak accelerating voltages of around 50 MV, with about 60 meters of straight-section space available for accelerating structures. 8 refs

Active interlock system for high power insertion devices in the x-ray ring

International Nuclear Information System (INIS)

Anon.

1991-01-01

In modern synchrotron radiation rings photon beams generated by high power insertion devices (IDs) may be sufficiently intense to cause severe thermal damage to the machine vacuum chamber if mis-steered. Thus when operating a storage ring with the IDs, great care must be exercised to prevent mis-steering of the electron beam orbit. At present, the X-ray ring operates with three IDs, namely two hybrid wigglers (HBW) at X-21 and X-25,a nd a 5-Tesla superconducting wiggler at X-17. All wigglers are located in low-beta straight sections. In the straight sections. In the straight sections, beam orbit may be deflected by as much as ±8 mrad without scraping the chamber wall. For various reasons it was not possible to design the X-ray ring vacuum chamber to be safe under all possible operating conditions, however, the chamber is safe for i < 7 mA, all horizontal beam deflection angles and for vertical angles < ± 2.5 mrad. To protect the machine vacuum chamber from damage due to mis-steered beams, and interlock system has been developed and installed. This system utilizes active beam position detectors which continuously monitor beam motion in each of the ID straight sections and logic circuitry which interrupts the RF and dumps the stored beam in the case of a fault

Environment education for taking of decision. One challenge for the sector cuban cooperative

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Miladys Garrido Cervera

2015-12-01

The present work have like purpose demonstrate the importance that reviewer include the environment theme in the process of taking of decisions in the farming cooperative to make up the aspect 133 of the economic politic and social in the new Cuban economic model. To do that one analysis about the environment education and the relationship tighten what have with the cooperative development for the guarantee of good practice, guarantee real one development sustainable.

Cuban and antinjerencismo in the Government of the Hundred Days

Directory of Open Access Journals (Sweden)

Lourdes María Rodríguez Rodríguez

2005-12-01

Full Text Available This article in essence expresses the characteristics of a government of the Neocolonial Republic, known by its heterogeneous distinction, and for its revolutionary projection in correspondence with the moment they lived, not only in its internal projection, but also in its foreign policy, in the international relationships area as a common expression of a Latin American feeling, that for the decade of the 30', it was an irrevocable reality: the anti colonial feeling; therefore it allows a better understanding of the process of formation of the nationality and of the Cuban nation, main objective of the study programs of the subject History of Cuba.

Comparison of Childrearing Practices of Anglos, Cuban-Americans, and Latin Americans. Occasional Papers Series, Dialogues #5.

Science.gov (United States)

Escovar, Luis; Escovar, Peggy L.

In this report perceived childrearing practices among three cultural groups (American Anglos, Cuban Americans, and Latin Americans) were compared. Subjects were 445 college students (168 males and females from universities in Colombia and Venezuela, and 154 from a university in South Florida). A multivariate analysis of covariance was used to…

The LSU Electron Storage Ring, the first commercially-built storage ring

International Nuclear Information System (INIS)

Sah, R.

1990-01-01

The Brobeck Division of Maxwell Laboratories, Inc., is building the first industrially-produced storage ring. It will be located at Louisiana State University (LSU) at the Center for Advanced Microstructures and Devices (CAMD) in Baton Rouge. The purpose of this electron storage ring is to provide intense beams of x-rays to advance the state-of-the-art in lithography and to permit research in a broad area. This facility consists of a 1.2 GeV, 400 mA electron storage ring with a 200 MeV linac injector. The magnet lattice is a Chasman-Green design (double-bend achromat), and the ring circumference is 55.2 meters. There are four 3.0 meter, dispersion-free straight sections, one for injection, one for the 500 MHz RF cavity, and two for possible future insertion devices. The storge ring construction project is in the detailed-design stage, and many systems are in the initial stages of fabrication. 4 figs., 1 tab

Saturn's Ring: Pre-Cassini Status and Mission Goals

Science.gov (United States)

Cuzzi, Jeff N.; DeVincenzi, Donald L. (Technical Monitor)

1999-01-01

In November 1980, and again in August 1981, identical Voyager spacecraft flew through the Saturn system, changing forever the way we think about planetary rings. Although Saturn's rings had been the only known ring system for three centuries, a ring system around Uranus had been discovered by stellar occultations from Earth in 1977, and the nearly transparent ring of Jupiter was imaged by Voyager in 1979 (the presence of material there had been inferred from charged particle experiments on Pioneer 10 and 11 several years earlier). While Saturn had thus temporarily lost its uniqueness as having the only ring system, with Voyager it handily recaptured the role of having the most fascinating one. The Voyager breakthroughs included spiral density and bending waves such as cause galactic structure; ubiquitous fine-scale radial 'irregular' structure, with the appearance of record-grooves; regional and local variations in particle color; complex, azimuthally variable ring structure; empty gaps in the rings, some containing very regular, sharp-edged, elliptical rings and one containing both a small moonlet and incomplete arcs of dusty material; and shadowy 'spokes' that flicker across the main rings. One of the paradigm shifts of this period was the realization that many aspects of planetary rings, and even the ring systems themselves, could be 'recent' on geological timescales. These early results are reviewed and summarized in the Arizona Space Science series volumes 'Saturn'. (An excellent review of ring dynamics at a formative stage is by Goldreich and Tremaine.) From the mid 1980's to the time of this writing, progress has been steady, while at a less heady pace, and some of the novel ring properties revealed by Voyager 1 and 2 are beginning to be better understood. It is clearly impossible to cite, much less review, every advance over the last decade; however, below we summarize the main advances in understanding of Saturn's rings since the mid 1980's, in the context

Construction of vacuum system for Tristan accumulation ring

International Nuclear Information System (INIS)

Ishimaru, H.; Horikoshi, G.; Kobayashi, M.; Kubo, T.; Mizuno, H.; Momose, T.; Narushima, K.; Watanabe, H.; Yamaguchi, H.

1983-01-01

An all aluminum-alloy vacuum system for the TRISTAN accumulation ring is now under construction. Aluminum and aluminum alloys are preferred materials for ultrahigh vacuum systems of large electron storage rings because of their good thermal conductivity, extremely low outgassing rate, and low residual radioactivity. Vacuum beam chambers for the dipole and quadrupole magnets are extruded using porthole dies. The aluminum alloy 6063-T6 provides superior performance in extrusion. For ultrahigh vacuum performance, a special extrusion technique is applied which, along with the outgassing procedure used, is described in detail. Aluminum alloy 3004 seamless elliptical bellows are inserted between the dipole and quadrupole magnet chambers. These bellows are produced by the hydraulic forming of a seamless tube. The seamless bellows and the beam chambers are joined by fully automatic welding. The ceramic chambers for the kicker magnets, the fast bump magnets, and the slow beam intensity monitor are inserted in the aluminum alloy beam chambers. The ceramic chamber (98% alumina) and elliptical bellows are brazed with brazing sheets (4003-3003-4003) in a vacuum furnace. The brazing technique is described. The inner surface of the ceramic chamber is coated with a TiMo alloy by vacuum evaporation to permit a smooth flow of the RF wall current. Other suitable aluminum alloy components, including fittings, feedthroughs, gauges, optical windows, sputter ion pumps, turbomolecular pumps, and valves have been developed; their fabrication is described

Mechanistic Studies of Metal-Oxo Cubane Catalysts for Lightweight Solar Fuels Storage

Science.gov (United States)

2013-03-01

13692. 4 “ Single - crystal growth, crystal and electronic structure of NaCoO2.” Takahashi, Y.; Gotoh, Y.; Akimoto, J. J. Sol. State Chem. 2003, 172, 22...bond formation by the Co–OEC catalysts. 2. A penetrating study of Co3 +|Co4+ self-exchange kinetics of Co4O4 cubanes and a detailed understanding of...construct the artificial leaf described in (7). 4. The examination of Co2+| Co3 + self-exchange in a faithful structural molecular analog of the 7

The New Horizons and Hubble Space Telescope search for rings, dust, and debris in the Pluto-Charon system

Science.gov (United States)

Lauer, Tod R.; Throop, Henry B.; Showalter, Mark R.; Weaver, Harold A.; Stern, S. Alan; Spencer, John R.; Buie, Marc W.; Hamilton, Douglas P.; Porter, Simon B.; Verbiscer, Anne J.; Young, Leslie A.; Olkin, Cathy B.; Ennico, Kimberly; New Horizons Science Team

2018-02-01

We conducted an extensive search for dust or debris rings in the Pluto-Charon system before, during, and after the New Horizons encounter in July 2015. Methodologies included attempting to detect features by back-scattered light during the approach to Pluto (phase angle α ∼ 15°), in situ detection of impacting particles, a search for stellar occultations near the time of closest approach, and by forward-scattered light imaging during departure (α ∼ 165°). An extensive search using the Hubble Space Telescope (HST) prior to the encounter also contributed to the final ring limits. No rings, debris, or dust features were observed, but our new detection limits provide a substantially improved picture of the environment throughout the Pluto-Charon system. Searches for rings in back-scattered light covered the range 35,000-250,000 km from the system barycenter, a zone that starts interior to the orbit of Styx, the innermost minor satellite, and extends out to four times the orbital radius of Hydra, the outermost known satellite. We obtained our firmest limits using data from the New Horizons LORRI camera in the inner half of this region. Our limits on the normal I/F of an unseen ring depends on the radial scale of the rings: 2 ×10-8 (3σ) for 1500 km wide rings, 1 ×10-8 for 6000 km rings, and 7 ×10-9 for 12,000 km rings. Beyond ∼ 100, 000 km from Pluto, HST observations limit normal I/F to ∼ 8 ×10-8 . Searches for dust features from forward-scattered light extended from the surface of Pluto to the Pluto-Charon Hill sphere (rHill = 6.4 ×106 km). No evidence for rings or dust clouds was detected to normal I/F limits of ∼ 8.9 ×10-7 on ∼ 104 km scales. Four stellar occulation observations also probed the space interior to Hydra, but again no dust or debris was detected. The Student Dust Counter detected one particle impact 3.6 × 106 km from Pluto, but this is consistent with the interplanetary space environment established during the cruise of New

The provincial archive as a place of memory: confronting oral and written sources on the role of former slaves in the Cuban war of independence (1895-98

Directory of Open Access Journals (Sweden)

Rebecca J. Scott

2002-07-01

Full Text Available Focuses on the study of the role of former slaves in the Cuban War of Independence, in light of the avoidance of the theme of race within this war in Cuban historiography. Author discusses reasons for the silence on race issues, and for the historic construction of the "myth" of racial equality in this era. Then, she points at the difficulties in the studying of the presence of former slaves among the Cuban soldiers in the War of Independence, due to the absence of racial labels for the registered soldiers. She describes how the research on the theme became more local, and focused on the Cienfuegos region, in part because of Cienfuegos' extensive local archive. Then, she outlines the different approaches to research on the matter by the archives' director Orlando García Martínez, by Michael Zeuske, and by the author herself. The latter explains how she extended her archival research with oral testimonies of descendants in Cienfuegos of black soldiers, and how through examining life histories, collective biographies, and genealogies, she ascertained that the number of former slaves in the rebellious Cuban army was relatively small, but the number of free-born blacks and mulattoes was high.

Ring faults and ring dikes around the Orientale basin on the Moon.

Science.gov (United States)

Andrews-Hanna, Jeffrey C; Head, James W; Johnson, Brandon; Keane, James T; Kiefer, Walter S; McGovern, Patrick J; Neumann, Gregory A; Wieczorek, Mark A; Zuber, Maria T

2018-08-01

The Orientale basin is the youngest and best-preserved multiring impact basin on the Moon, having experienced only modest modification by subsequent impacts and volcanism. Orientale is often treated as the type example of a multiring basin, with three prominent rings outside of the inner depression: the Inner Rook Montes, the Outer Rook Montes, and the Cordillera. Here we use gravity data from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission to reveal the subsurface structure of Orientale and its ring system. Gradients of the gravity data reveal a continuous ring dike intruded into the Outer Rook along the plane of the fault associated with the ring scarp. The volume of this ring dike is ~18 times greater than the volume of all extrusive mare deposits associated with the basin. The gravity gradient signature of the Cordillera ring indicates an offset along the fault across a shallow density interface, interpreted to be the base of the low-density ejecta blanket. Both gravity gradients and crustal thickness models indicate that the edge of the central cavity is shifted inward relative to the equivalent Inner Rook ring at the surface. Models of the deep basin structure show inflections along the crust-mantle interface at both the Outer Rook and Cordillera rings, indicating that the basin ring faults extend from the surface to at least the base of the crust. Fault dips range from 13-22° for the Cordillera fault in the northeastern quadrant, to 90° for the Outer Rook in the northwestern quadrant. The fault dips for both outer rings are lowest in the northeast, possibly due to the effects of either the direction of projectile motion or regional gradients in pre-impact crustal thickness. Similar ring dikes and ring faults are observed around the majority of lunar basins.

Heterometal cubane-type MFe(3)S(4) clusters (M = Mo, V) trigonally symmetrized with hydrotris(pyrazolyl)borate(1-) and tris(pyrazolyl)methanesulfonate(1-) capping ligands.

Science.gov (United States)

Fomitchev, Dmitry V; McLauchlan, Craig C; Holm, R H

2002-02-25

A series of heterometal cubane-type clusters containing [VFe(3)S(4)](2+) and [MoFe(3)S(4)](3+,2+) cores has been prepared. Ligand substitution of [(DMF)(3)VFe(3)S(4)Cl(3)](-) affords [(Tpms)VFe(3)S(4)L(3)](2)(-) (L = Cl(-) (8), EtS(-) (9), p-MeC(6)H(4)S(-), p-MeC(6)H(4)O(-)). A new procedure for the preparation of molybdenum single cubanes is introduced by the reaction of recently reported [(Tp)MoS(S(4))](-) with FeCl(2)/NaSEt to afford [(Tp)MoFe(3)S(4)Cl(3)](-) (1, 75% yield). This procedure is more efficient that the existing multistep synthesis of single cubanes, which generally affords clusters of mirror symmetry. Also prepared were [(Tp)MoFe(3)S(4)L(3)](-) (L = EtS(-) (2), p-MeC(6)H(4)S(-)). Reduction of 1 with borohydride gives [(Tp)MoFe(3)S(4)Cl(3)](2-) (5, 67%). Owing to the nature of the heterometal ligand, all clusters have idealized trigonal symmetry, reflected in their (1)H NMR spectra. Trigonal structures are demonstrated by crystallography of (Bu(4)N)[1,2], (Bu(4)N)(2)[5] x MeCN, and (Me(4)N)(2)[8,9]. The availability of 1 and 5 allows the first comparison of structures and (57)Fe isomer shifts of [MoFe(3)S(4)](3+,2+) in a constant ligand environment. Small increases in most bond distances indicate that an antibonding electron is added in the reduction of 1. Collective synthetic and electrochemical results from this and other studies demonstrate the existence of the series of oxidation states [VFe(3)S(4)](3+,2+,1+) and [MoFe(3)S(4)](4+,3+,2+) whose relative stabilities within a given series are strongly ligand dependent. Isomer shifts indicate that the reduction of 1 largely affects the Fe(3) subcluster and are consistent with the formal descriptions [MoFe(3+)(2)Fe(2+)S(4)](3+) (1) and [MoFe(3+)Fe(2+)(2)S(4)](2+) (5). Reaction of 1 with excess Li(2)S in acetonitrile affords the double cubane [[(Tp)MoFe(3)S(4)Cl(2)](2)(mu(2)(-)S)](2)(-), whose sulfide-bridged structure is supported by two sequential reductions separated by 290 mV, in analogy with

Expanding the classroom with educational technology: A case study of a Cuban polytechnic high school

Directory of Open Access Journals (Sweden)

Anne Leftwich

2014-12-01

Full Text Available Polytechnic instruction has a common place in the Cuban education system (Gasperini, 2000. In polytechnic institutions, teachers leverage technological tools to prepare students for labor market competences. This case study examined a polytechnic institution in Cuba to consider how teachers defined educational technology. Based on teacher questionnaire responses, site-based teacher interviews, and field observations, technology was primarily viewed as a method for student preparation. In other words, teachers used technology to prepare students for their future careers and the technology they will need to be successful in that career. The study found that teachers highly valued their technical pedagogical training, believed that the growing spaces were an integral part of their technology based instruction, and claimed that the limited resources was their greatest barrier to integrating ICT in the classroom.

Trump And Obama’s “Cuban Legacy”

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Kh. Sh. Ulugova

2017-01-01

Full Text Available After the triumph of revolution in Cuba in 1959 Washington and Havana have been hostile to each other for more than half a century. Even the end of the Cold War and disintegration of the bipolar international system left intact the antagonism between the two. Only after Barack Obama came to power did normalization become possible. He admitted the failure of the policy of sanctions and declared a “new beginning” in US-Cuba relations. There is a risk now that under the new administration of Donald Trump the efforts made before can be neutralized if the US president keeps his recent pre-election promise and cancels all the previous agreements on normalization. The question remains open – whether Obama’s achievements in this regard will be preserved or Trump will manage to reverse the normalization policy of his predecessor. There will be either pragmatic Trump the businessman who understands the benefits of continuing Obama’s policy, or Trump the politician who will stand firm on his pre-election pledge to roll back on once promising initiative. The article analyzes the process of normalization initiated by Obama and Castro in 2014, explains its background motivations and builds various scenarios of further development of Cuban-American relations, as well as Trump’s policy towards Cuba. It is unlikely that the Trump administration will abandon what has already been achieved. It may entail significant political and economic costs, which is unacceptable for Trump the businessman. However, any new progressive steps towards the normalization should not be expected in the short term.

Distinguishing Features of Cuban Children Referred for Professional Help Because of ADHD: Looking beyond the Symptoms

Science.gov (United States)

Schneider, Barry H.; Normand, Sebastien; Sotares deToro, Maria del Pilar; Santana Gonzalez, Yorkys; Guilarte Tellez, Jorge Antonio; Carbonell Naranjo, Migdalia; Musle, Miriam; Diaz Socarras, Felix Javier; Robaey, Philippe

2011-01-01

Objective: To distinguish Cuban children clinically referred because of ADHD from an at-risk community sample and a community control group in terms of symptoms, associated difficulties and impairment of family and peer relations. Method: Parents and teachers of 1,036 children (6-8 years old) completed an established ADHD rating scale and a…

A Witness to French-Cuban Cooperation in Physics in the 1970s

Science.gov (United States)

Cernogora, Jacqueline

In France in 1968 many lively discussions and debates took place at several universities and laboratories in which official authority was questioned. Very often in such debates someone would stand up and ask the previous speaker: "Who are you to assert such a thing?" or "From where are you speaking?" Forty years later, to avoid such questions, I will say right away "from where" I am writing this text, which is by no means an exhaustive study of French-Cuban collaboration in physics at that time, but rather a personal recollection.

Analysis of the Socio-Educational Dimension of the Cuban Woman in Negra of Wendy Guerra

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Pilar Navarro Galiano

2016-12-01

Full Text Available This job is based on the novel written by the author Wendy Guerra, Negra. Firstly, a study about social and education situation of the cuban woman since the colonial phase to the present day is accomplished as well. Finally, the main topics in her novel Negra such as racism, sex, witchcraft, music, magic and religion will be analysed.

Conceptual Design of ILC Damping Ring Wiggler Straight Vacuum System

International Nuclear Information System (INIS)

Marks, S.; Kennedy, K.; Plate, D.; Schlueter, R.D.; Zisman, M.

2007-01-01

The positron and electron damping rings for the International Linear Collider will contain long straight sections consisting of twenty wiggler/quadrupole pairs. The wigglers will be based upon the CESR superconducting design. There are a number of challenges associated with the design of the wiggler straight vacuum system, in particular, the absorption of photon power generated by the wigglers. This paper will present the overall conceptual design of the wiggler straight vacuum system developed for the ILC Reference Design Report. Particular emphasis will be placed on photon power load calculations and the absorber design

Saturn's Rings Edge-on

Science.gov (United States)

1995-01-01

In one of nature's most dramatic examples of 'now-you see-them, now-you-don't', NASA's Hubble Space Telescope captured Saturn on May 22, 1995 as the planet's magnificent ring system turned edge-on. This ring-plane crossing occurs approximately every 15 years when the Earth passes through Saturn's ring plane.For comparison, the top picture was taken by Hubble on December 1, 1994 and shows the rings in a more familiar configuration for Earth observers.The bottom picture was taken shortly before the ring plane crossing. The rings do not disappear completely because the edge of the rings reflects sunlight. The dark band across the middle of Saturn is the shadow of the rings cast on the planet (the Sun is almost 3 degrees above the ring plane.) The bright stripe directly above the ring shadow is caused by sunlight reflected off the rings onto Saturn's atmosphere. Two of Saturn's icy moons are visible as tiny starlike objects in or near the ring plane. They are, from left to right, Tethys (slightly above the ring plane) and Dione.This observation will be used to determine the time of ring-plane crossing and the thickness of the main rings and to search for as yet undiscovered satellites. Knowledge of the exact time of ring-plane crossing will lead to an improved determination of the rate at which Saturn 'wobbles' about its axis (polar precession).Both pictures were taken with Hubble's Wide Field Planetary Camera 2. The top image was taken in visible light. Saturn's disk appears different in the bottom image because a narrowband filter (which only lets through light that is not absorbed by methane gas in Saturn's atmosphere) was used to reduce the bright glare of the planet. Though Saturn is approximately 900 million miles away, Hubble can see details as small as 450 miles across.The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science.This image and other images and

TRANSIT MODEL OF PLANETS WITH MOON AND RING SYSTEMS

International Nuclear Information System (INIS)

Tusnski, Luis Ricardo M.; Valio, Adriana

2011-01-01

Since the discovery of the first exoplanets, those most adequate for life to begin and evolve have been sought. Due to observational bias, however, most of the discovered planets so far are gas giants, precluding their habitability. However, if these hot Jupiters are located in the habitable zones of their host stars, and if rocky moons orbit them, then these moons may be habitable. In this work, we present a model for planetary transit simulation considering the presence of moons and planetary rings around a planet. The moon's orbit is considered to be circular and coplanar with the planetary orbit. The other physical and orbital parameters of the star, planet, moon, and rings can be adjusted in each simulation. It is possible to simulate as many successive transits as desired. Since the presence of spots on the surface of the star may produce a signal similar to that of the presence of a moon, our model also allows for the inclusion of starspots. The result of the simulation is a light curve with a planetary transit. White noise may also be added to the light curves to produce curves similar to those obtained by the CoRoT and Kepler space telescopes. The goal is to determine the criteria for detectability of moons and/or ring systems using photometry. The results show that it is possible to detect moons with radii as little as 1.3 R ⊕ with CoRoT and 0.3 R ⊕ with Kepler.

Ring Theory

CERN Document Server

Jara, Pascual; Torrecillas, Blas

1988-01-01

The papers in this proceedings volume are selected research papers in different areas of ring theory, including graded rings, differential operator rings, K-theory of noetherian rings, torsion theory, regular rings, cohomology of algebras, local cohomology of noncommutative rings. The book will be important for mathematicians active in research in ring theory.

Principales resultados del sistema cubano de Farmacovigilancia en el año 2004 Main results of the Cuban system of pharmacological surveillance system in 2004

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Francisco Debesa García

2005-12-01

Full Text Available Se describen los principales resultados alcanzados por el sistema cubano de Farmacovigilancia en el 2004. Durante 12 meses, los casos se identificaron mediante el sistema de notificación voluntaria de sospecha de reacciones adversas a medicamentos. Se recibieron en la Unidad Nacional Coordinadora de Farmacovigilancia 7 063 notificaciones de reacciones adversas medicamentosas (RAM que contenían 13 500 a razón de 1,9 RAM por notificación, de ellas 3 185 fueron “importantes” para el 35,1 % (según criterios para determinar RAM importantes de la UCNFv , en las Normas y procedimientos de trabajo del sistema cubano de Farmacovigilancia. La tasa de notificación anual fue de 628 notificaciones por millón de habitantes. El 64,6 % de las RAM correspondió al sexo femenino y el 35,4 % al masculino. En cuanto al nivel de asistencia, la atención primaria fue la que más notificó con 85 %. La relación de reacciones leves con respecto a las moderadas y graves fue de 48,3/51,4 %, que continúa con un balance muy bueno en relación con el reporte por severidad. Se reportaron 23 reacciones con desenlace fatal, para el 0,3 %. A pesar de la disminución en cuanto al número de notificaciones recibidas en nuestro unidad, con respecto al año anterior, aún se encuentra entre las tasas de notificación más altas de los países miembros del sistema internacional de monitoreo de RAM; por otra parte, dada la calidad de estas permitieron cuantificar y caracterizar las RAM, teniendo además un gran valor para generar alertas y vigilar la seguridad de los medicamentos que circulan en nuestro país.The main results achieved by the Cuban Pharmacological Surveillance System in the year 2004 were described. During these 12 months, the cases were identified by the voluntary notification system of suspected adverse reactions to drugs. The National Coordinating Unit of Pharmacological Surveillance (NCUPs received 7 063 notifications that included 13 500 adverse drug

SOR-ring failure

International Nuclear Information System (INIS)

Kitamura, Hideo

1981-01-01

It was in the autumn of 1976 that the SOR-ring (synchrotron radiation storage ring) has commenced the regular operation. Since then, the period when the operation was interrupted due to the failures of SOR-ring itself is in total about 8 weeks. Failures and accidents have occurred most in the vacuum system. Those failure experiences are described on the vacuum, electromagnet, radio-frequency acceleration and beam transport systems with their interrupted periods. The eleven failures in the vacuum system have been reported, such as bellows breakage in a heating-evacuating period, leakage from the bellows of straight-through valves (made in U.S.A. and Japan), and leakage from the joint flange of the vacuum system. The longest interruption was 5 weeks due to the failure of a domestically manufactured straight-through valve. The failures of the electromagnet system involve the breakage in a cooling water system, short circuit of a winding in the Q magnet power transformer, blow of a fuse protecting the deflection magnet power source by the current less than the rating, and others. The failures of the RF acceleration system include the breakage of an output electronic tube the breakage of a cavity ceramic, RF voltage fluctuation due to the contact deterioration at a cavity electrode, and the failure of grid bias power source. It is necessary to select the highly reliable components for the vacuum system because the vacuum system failures require longer time for recovery, and very likely to induce secondary and tertiary failures. (Wakatsuki, Y.)

A technique for ecological studies of the cuban fly, 'Lixophaga diatraea' TOWNS., com o uso de tracador radioativo

International Nuclear Information System (INIS)

Sgrillo, R.B.; Wiendl, F.M; Walder, J.M.M; Arthur, V.

1977-01-01

The specific activity of 32 P required to label Cuban Fly (lixophaga diatraca) is determined. Results show that the radioisotope can be detected inside the bodies of G. mellonella host for at least 6 days, with effective half-life for the raioisotope of 2.8 days [pt

How Jupiter's Ring Was Discovered.

Science.gov (United States)

Elliot, James; Kerr, Richard

1985-01-01

"Rings" (by astronomer James Elliot and science writer Richard Kerr) is a nontechnical book about the discovery and exploration of ring systems from the time of Galileo to the era of the Voyager spacecraft. One of this book's chapters is presented. (JN)

The Lord of Rings - the mysterious case of the stolen rings: a critical analysis

Science.gov (United States)

Sandrelli, S.

The Lord of Rings - the mysterious case of the stolen rings: a critical analysis S. Sandrelli INAF - Osservatorio Astronomico di Brera, Milano, Italy (stefano.sandrelli@brera.inaf.it / Fax: 02 72001600 / Phone: +39 02 72320337) "The Lord of Rings - the mysterious case of the stolen rings" is a live astronomical role-playing game for kids aged 10 -13. Its goal is to introduce them to some of the main topics of the Solar System: a) the role of gravity; b) the distribution of mass & light; c) the effects of rotation; d) the distribution of water. The game was held both at the Perugia (2004) and the Genova Science Festival (2005), obtaining great success. Teams of about 6-8 members are introduced to Mr Schioppanelli, the astro-detective of the town (the name is a pun: it reminds Schiaparelli, the famous italian astronomer, and it is a slang expression meaning "ring-breaker"). Mr Schioppanelli has his office in an "gastronomical astronomical observatory", known as The Red Giant Pizzeria. Schioppanelli informs the kids that a mysterious Centaur succeded in stealing the rings of Saturn. The partecipants are appointed astro-detectives in-charge and asked to find the rings by browsing around the Solar System, which is scaled so as to fit the town historical centre or a pedestrian area, going from the Sun to Saturn or beyond, depending on the actual area at disposal. Great care must be taken allowing children playing only in a car-free area of the town. At the right scaled distances, the partecipants meet characters playing as the various planets. The kids can talk to them after solving a riddle, obtaining useful informations. A special characters play as a comet, timely going in and out of the inner solar system. The teams can also talk to some shepherd-moons of the rings. They easily discover that the rings were totally destroyed by the Centaur: a real disaster! They are also suggested to gather the necessary ingredients (gravity, light, rotation, inclination, dust and

Magnet power supply system for the ALS storage ring and booster

International Nuclear Information System (INIS)

Jackson, L.T.; Luchini, K.; Lutz, I.

1993-05-01

The Magnet Power Supply System is described by specification, design, hardware, and operating experience. A unique system for the one Hz, 1.5 GeV Booster, where the wideband QF and QD power supplies track the dipole current to within 0.1% at injection will be detailed. AC distribution system considerations related to inverting the stored energy of the booster magnet back into power grid will be discussed. The rational for linear correctors and individual quad supplies (225 total units) will be placed within the context of the storage-ring requirements

Fundamentación Científica de la Psiquiatría Cubana Actual Current Cuban Psychiatry: Its scientific foundation

Directory of Open Access Journals (Sweden)

Liuba Y Peña Galbán

2007-08-01

Full Text Available Se realiza un análisis metodológico conceptual de la Psiquiatría como ciencia partiendo de los criterios de los psiquiatras cubanos, coincidiendo en que es una rama de las Ciencias Médicas, en la cual el objeto de estudio es la enfermedad mental o el proceso salud enfermedad mental y sus acciones es el diagnóstico, tratamiento, etiopatogenia, rehabilitación y prevención de las mismas, así como su estudio epidemiológico y que incluye el carácter social e interdisciplinario. A partir de la reorientación de la Psiquiatría hacia la comunidad se hace una reflexión del significado e implicaciones de la misma. Se argumenta como en Cuba se aplica el Modelo de la Atención Comunitaria de Salud Mental a través de los Centros comunitarios de Salud Mental que constituyen la piedra angular del modelo cubano de atención comunitaria, con los que constituye la Psiquiatría comunitaria el nuevo paradigma de la Psiquiatría cubana actual. Se reconoce que el fundamento filosófico que sustenta a la Psiquiatría cubana actual es la teoría Marxista LeninistaA conceptual and methodological analysis of Psychiatry as a science is made, taking the Cuban psychiatrists' criteria as a starting point, referring to it as a branch of the Medical Sciences, in which the object of study is the mental illness or the process health-mental illness, being its actions the diagnosis, treatment, ethiology and pathogenesis, rehabilitation and prevention, as well as its epidemiological study that is related to the social and interdisciplinary levels. Starting with redirecting Psychiatry towards the community, a reflection is made of the meaning and implications of this science. It is documented the application of the Community Mental Health Attention Model that is applied through the community Centers of Mental Health, which constitute the cornerstone of the Cuban model of community attention. Thus, community Psychiatry represents the new paradigm of current Cuban

Magnetization of two coupled rings

International Nuclear Information System (INIS)

Avishai, Y; Luck, J M

2009-01-01

We investigate the persistent currents and magnetization of a mesoscopic system consisting of two clean metallic rings sharing a single contact point in a magnetic field. Many novel features with respect to the single-ring geometry are underlined, including the explicit dependence of wavefunctions on the Aharonov-Bohm fluxes, the complex pattern of two-fold and three-fold degeneracies, the key role of length and flux commensurability, and in the case of commensurate ring lengths the occurrence of idle levels which do not carry any current. Spin-orbit interactions, induced by the electric fields of charged wires threading the rings, give rise to a peculiar version of the Aharonov-Casher effect where, unlike for a single ring, spin is not conserved. Remarkably enough, this can only be realized when the Aharonov-Bohm fluxes in both rings are neither integer nor half-integer multiples of the flux quantum

Infrared cavity ring-down spectroscopy with a CW diode laser system

NARCIS (Netherlands)

Hemerik, M.M.; Kroesen, G.M.W.; Doebele, H.F.; Muraoka, K.

1999-01-01

We report on the first measurements with our CRDS setup. Although the diode laser system was out of order, we were able to test the most important parts with the use of a CO laser. The first results show a ring-down time of 1.54 ~is, which is in perfect agreement with the predicted reflectivity of

Report of the eRHIC Ring-Ring Working Group

Energy Technology Data Exchange (ETDEWEB)

Aschenauer, E. C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brennan, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fedotov, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Litvinenko, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Montag, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Palmer, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Parker, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Peggs, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trbojevic, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Willeke, F. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-10-13

This report evaluates the ring-ring option for eRHIC as a lower risk alternative to the linac-ring option. The reduced risk goes along with a reduced initial luminosity performance. However, a luminosity upgrade path is kept open. This upgrade path consists of two branches, with the ultimate upgrade being either a ring-ring or a linac-ring scheme. The linac-ring upgrade could be almost identical to the proposed linac-ring scheme, which is based on an ERL in the RHIC tunnel. This linac-ring version has been studied in great detail over the past ten years, and its significant risks are known. On the other hand, no detailed work on an ultimate performance ring-ring scenario has been performed yet, other than the development of a consistent parameter set. Pursuing the ring-ring upgrade path introduces high risks and requires significant design work that is beyond the scope of this report.

The simulation of control system for the KEK main ring power supply, 1

International Nuclear Information System (INIS)

Sato, Hikaru; Shintomi, Takakazu; Kubo, Tadashi; Masuda, Masayoshi; Nakano, Michio.

1975-09-01

The simulation of control system for the KEK main ring power supply is performed. The inductance of the magnet is assumed to be linear against to the current. The results of the simulations are described. (auth.)

Immune Response Induction and New Effector Mechanisms Possibly Involved in Protection Conferred by the Cuban Anti-Meningococcal BC Vaccine

Science.gov (United States)

Pérez, Oliver; Lastre, Miriam; Lapinet, José; Bracho, Gustavo; Díaz, Miriam; Zayas, Caridad; Taboada, Carlos; Sierra, Gustavo

2001-01-01

This report explores the participation of some afferent mechanisms in the immune response induced by the Cuban anti-meningococcal vaccine VA-MENGOC-BC. The induction of delayed-type hypersensitivity in nursing babies and lymphocyte proliferation after immunization is demonstrated. The presence of gamma interferon IFN-γ and interleukin-2 (IL-2) mRNAs but absence of IL-4, IL-5, and IL-10 mRNAs were observed in peripheral blood mononuclear cells from immunized subjects after in vitro challenge with outer membrane vesicles. In addition, some effector functions were also explored. The presence of opsonic activity was demonstrated in sera from vaccinees. The role of neutrophils as essential effector cells was shown. In conclusion, we have shown that, at least in the Cuban adult population, VA-MENGOC-BC induces mechanisms with a T-helper 1 pattern in the afferent and effector branches of the immune response. PMID:11401992

Commissioning of the diamond light source storage ring vacuum system

International Nuclear Information System (INIS)

Cox, M P; Boussier, B; Bryan, S; Macdonald, B F; Shiers, H S

2008-01-01

The Diamond storage ring has been operating with a 3 GeV electron beam since September 2006 and 190 A.h of beam dose have been accumulated. The pressure in the storage ring is 4.2 10 -10 mbar without beam, rising to 7.9 10 -10 mbar with 125 mA of stored beam. Data on the storage ring vacuum performance and experience from commissioning and beam conditioning are presented

OSBPL10, RXRA and lipid metabolism confer African-ancestry protection against dengue haemorrhagic fever in admixed Cubans.

Directory of Open Access Journals (Sweden)

Beatriz Sierra

2017-02-01

Full Text Available Ethnic groups can display differential genetic susceptibility to infectious diseases. The arthropod-born viral dengue disease is one such disease, with empirical and limited genetic evidence showing that African ancestry may be protective against the haemorrhagic phenotype. Global ancestry analysis based on high-throughput genotyping in admixed populations can be used to test this hypothesis, while admixture mapping can map candidate protective genes. A Cuban dengue fever cohort was genotyped using a 2.5 million SNP chip. Global ancestry was ascertained through ADMIXTURE and used in a fine-matched corrected association study, while local ancestry was inferred by the RFMix algorithm. The expression of candidate genes was evaluated by RT-PCR in a Cuban dengue patient cohort and gene set enrichment analysis was performed in a Thai dengue transcriptome. OSBPL10 and RXRA candidate genes were identified, with most significant SNPs placed in inferred weak enhancers, promoters and lncRNAs. OSBPL10 had significantly lower expression in Africans than Europeans, while for RXRA several SNPs may differentially regulate its transcription between Africans and Europeans. Their expression was confirmed to change through dengue disease progression in Cuban patients and to vary with disease severity in a Thai transcriptome dataset. These genes interact in the LXR/RXR activation pathway that integrates lipid metabolism and immune functions, being a key player in dengue virus entrance into cells, its replication therein and in cytokine production. Knockdown of OSBPL10 expression in THP-1 cells by two shRNAs followed by DENV2 infection tests led to a significant reduction in DENV replication, being a direct functional proof that the lower OSBPL10 expression profile in Africans protects this ancestry against dengue disease.

Characterization and reactions of a Salix extractive with a unique ring system

Science.gov (United States)

Lawrence Landucci; Sally Ralph; Kolby Hirth

2003-01-01

An extractive compound with a novel ring system was isolated from the wood of Salix alba and was given the name Salucci. The compound was primarily identified from the 1D NMR, 2D NMR and LC-MSMS data and the structure investigated through reactions and derivatizations.

Revolutionizing Cuban Psychiatry: The Freud Wars, 1955-1970.

Science.gov (United States)

Lambe, Jennifer Lynn

2017-01-01

This article traces the battle over Freud within Cuban psychiatry from its pre-1959 origins through the "disappearance" of Freud by the early 1970s. It devotes particular attention to the visit of two Soviet psychiatrists to Cuba in the early 1960s as part of a broader campaign to promote Pavlov. The decade-long controversy over Freud responded to both theoretical and political concerns. If for some Freud represented political conservatism and theoretical mystification, Pavlov held out the promise of a dialectical materialist future. Meanwhile, other psychiatrists clung to psychodynamic perspectives, or at least the possibility of heterogeneity. The Freudians would end up on the losing side of this battle, with many departing Cuba over the course of the 1960s. But banishing Freud did not necessarily make for stalwart Pavlovians-or vanguard revolutionaries. Psychiatry would find itself relegated to a handmaiden position in the work of revolutionary mental engineering, with the government itself occupying the vanguard.

Electronic de-multipliers II (ring-shape systems); Demultiplieurs electroniques II (systeme en anneau)

Energy Technology Data Exchange (ETDEWEB)

Raievski, V

1948-09-01

This report describes a new type of ring-shape fast electronic counter (de-multiplier) with a resolution capacity equivalent to the one made by Regener (Rev. of Scientific Instruments USA 1946, 17, 180-89) but requiring two-times less electronic valves. This report follows the general description of electronic de-multipliers made by J. Ailloud (CEA--001). The ring comprises 5 flip-flop circuits with two valves each. The different elements of the ring are calculated with enough details to allow the transfer of this calculation to different valve types. (J.S.)

Ring-Expansion/Contraction Radical Crossover Reactions of Cyclic Alkoxyamines: A Mechanism for Ring Expansion-Controlled Radical Polymerization

Directory of Open Access Journals (Sweden)

Atsushi Narumi

2018-06-01

Full Text Available Macrocyclic polymers present an important class of macromolecules, displaying the reduced radius of gyration or impossibility to entangle. A rare approach for their synthesis is the ring expansion-controlled radical “vinyl” polymerization, starting from a cyclic alkoxyamine. We here describe ring-expansion radical crossover reactions of cyclic alkoxyamines which run in parallel to chain-propagation reactions in the polymerization system. The radical crossover reactions extensively occurred at 105–125 °C, eventually producing high molecular weight polymers with multiple inherent dynamic covalent bonds (NOC bonds. A subsequent ring-contraction radical crossover reaction and the second ring-expansion radical crossover reaction are also described. The major products for the respective three stages were shown to possess cyclic morphologies by the molecular weight profiles and the residual ratios for the NOC bonds (φ in %. In particular, the high φ values ranging from ca. 80% to 98% were achieved for this cyclic alkoxyamine system. This result verifies the high availability of this system as a tool demonstrating the ring-expansion “vinyl” polymerization that allows them to produce macrocyclic polymers via a one-step vinyl polymerization.

INJECTION EFFICIENCY IN COMPTON RING NESTOR

Directory of Open Access Journals (Sweden)

P. I. Gladkikh

2017-12-01

Full Text Available NESTOR is the hard X-ray source that is under commissioning at NSC KIPT. NESTOR based on the Compton scattering of laser photons on relativistic electrons. The structure of the facility can be represented as the following components: a linear accelerator, a transport channel, a storage ring, and a laser-optical system. Electrons are stored in the storage ring for energy of 40-200 MeV. Inevitable alignment errors of magnetic elements are strongly effect on the beam dynamics in the storage ring. These errors lead to a shift of the equilibrium orbit relative to the ideal one. Significant shift of the equilibrium orbit could lead to loss of the beam on physical apertures. Transverse sizes of electron and laser beams are only few tens of microns at the interaction point. The shift of electron beam at the interaction point could greatly complicate the operation adjustment of storage ring without sufficient beam position diagnostic system. This article presents the simulation results of the efficiency of electron beam accumulation in the NESTOR storage ring. Also, this article is devoted to electron beam dynamics due to alignment errors of magnetic element in the ring.

Testing reachability and stabilizability of systems over polynomial rings using Gröbner bases

NARCIS (Netherlands)

Habets, L.C.G.J.M.

1993-01-01

Conditions for the reachability and stabilizability of systems over polynomial rings are well-known in the literature. For a system $ \\Sigma = (A,B)$ they can be expressed as right-invertibility cconditions on the matrix $(zI - A \\mid B)$. Therefore there is quite a strong algebraic relationship

Storage ring development at the National Synchrotron Light Source

International Nuclear Information System (INIS)

Krinsky, S.; Bittner, J.; Fauchet, A.M.; Johnson, E.D.; Keane, J.; Murphy, J.; Nawrocky, R.J.; Rogers, J.; Singh, O.V.; Yu, L.H.

1991-09-01

This report contains papers on the following topics: Transverse Beam Profile Monitor; Bunch Length Measurements in the VUV Storage Ring; Photoelectric Effect Photon Beam Position Monitors; RF Receivers for Processing Electron Beam Pick-up Electrode Signals; Real-Time Global Orbit Feedback Systems; Local Orbit Feedback; Active Interlock System for High Power Insertion Devices in the X-ray Ring; Bunch Lengthening Cavity for the VUV Ring; SXLS Storage Ring Design

Sex and sentiment in Cuban tourism.

Science.gov (United States)

Babb, Florence E

2010-01-01

Helen Safa has been a leading program builder and pioneer in research that examines the complex intersections of gender, race, class, and nation in Latin America and the Caribbean. Her comparative research culminated in her influential book, The Myth of the Male Breadwinner: Women and Industrialization in the Caribbean (1995), which examined gender, family, and employment across three Caribbean societies. Over several decades Safa has inspired scholarship throughout the Caribbean and the Americas and her work is exemplary of engaged anthropology in the region. Here I present work I conducted in Cuba that was guided, like my work in Peru, Nicaragua, and southern Mexico by the writings of Safa and others who saw the critical need to bring gender into meaningful discussion in the field of Latin American and Caribbean studies. In what follows, drawn from my broader research on tourism in four nations, I explore and reflect on the contemporary dynamics of sex and romance tourism in Cuba. I suggest that the allure of this domain of tourism may be enhanced by Cuba's global political identity, and that Cuban women participating in commodified and intimate exchanges reveal an ability to get along in a market economy that generally excludes them.

Galactic rings revisited - I. CVRHS classifications of 3962 ringed galaxies from the Galaxy Zoo 2 Database

Science.gov (United States)

Buta, Ronald J.

2017-11-01

Rings are important and characteristic features of disc-shaped galaxies. This paper is the first in a series that re-visits galactic rings with the goals of further understanding the nature of the features and for examining their role in the secular evolution of galaxy structure. The series begins with a new sample of 3962 galaxies drawn from the Galaxy Zoo 2 citizen science data base, selected because zoo volunteers recognized a ring-shaped pattern in the morphology as seen in Sloan Digital Sky Survey colour images. The galaxies are classified within the framework of the Comprehensive de Vaucouleurs revised Hubble-Sandage system. It is found that zoo volunteers cued on the same kinds of ring-like features that were recognized in the 1995 Catalogue of Southern Ringed Galaxies. This paper presents the full catalogue of morphological classifications, comparisons with other sources of classifications and some histograms designed mainly to highlight the content of the catalogue. The advantages of the sample are its large size and the generally good quality of the images; the main disadvantage is the low physical resolution that limits the detectability of linearly small rings such as nuclear rings. The catalogue includes mainly inner and outer disc rings and lenses. Cataclysmic (`encounter-driven') rings (such as ring and polar ring galaxies) are recognized in less than 1 per cent of the sample.

Developments in Geometric Metadata and Tools at the PDS Ring-Moon Systems Node

Science.gov (United States)

Showalter, M. R.; Ballard, L.; French, R. S.; Gordon, M. K.; Tiscareno, M. S.

2018-04-01

Object-Oriented Python/SPICE (OOPS) is an overlay on the SPICE toolkit that vastly simplifies and speeds up geometry calculations for planetary data products. This toolkit is the basis for much of the development at the PDS Ring-Moon Systems Node.

Monitor and control systems for the SLD Cherenkov Ring Imaging Detector

International Nuclear Information System (INIS)

Antilogus, P.; Aston, D.; Bienz, T.; Boston Univ., MA; California Univ., Santa Barbara, CA; California Univ., Santa Cruz, CA; Cincinnati Univ., OH; Rutgers--the State Univ., Piscataway, NJ; Tohoku Univ., Sendai

1989-10-01

To help ensure the stable long-term operation of a Cherenkov Ring Detector at high efficiency, a comprehensive monitor and control system is being developed. This system will continuously monitor and maintain the correct operating temperatures, and will provide an on-line monitor and maintain the correct operating temperatures, and will provide an on-line monitor of the pressures, flows, mixing, and purity of the various fluids. In addition the velocities and trajectories of Cherenkov photoelectrons drifting within the imaging chambers will be measured using a pulsed uv lamp and a fiberoptic light injection system. 9 refs., 6 figs

Comparison of cold and warm vacuum systems for intersecting storage rings

International Nuclear Information System (INIS)

Halama, H.J.; Herrera, J.C.

1975-01-01

In storage rings employing superconducting magnets, the use of a cold bore as a cryopump appears, at first glance, as simple and economical. Since the selection of a cold or warm vacuum system has far-reaching implications on the basic design, each system is considered in some detail. The theoretical and practical limitations imposed on the maximum beam current by the gas desorption from the chamber walls are discussed. A realistic design of a cold vacuum chamber is developed and then compared with the proposed warm ISABELLE vacuum system. The comparison shows that the warm approach is preferable. (U.S.)

Possible origin of Saturn's newly discovered outer ring

International Nuclear Information System (INIS)

Moehlmann, D.

1986-01-01

Within a planetogonic model the self-gravitationally caused formation of pre-planetary and pre-satellite rings from an earlier thin disk is reported. The theoretically derived orbital radii of these rings are compared with the orbital levels in the planetary system and the satellite systems of Jupiter, Saturn and Uranus. From this comparison it is concluded that at the radial position of Saturn's newly discovered outer ring an early pre-satellite ring of more or less evolved satellites could have existed. These satellites should have been disturbed in their evolution by the gravitation of the neighbouring massive satellite Titan. The comparison also may indicate similarities between the asteroidal belt and the newly discovered outer ring of Saturn

The Saturnian rings

International Nuclear Information System (INIS)

Alfven, H.

1975-09-01

The structure of the Saturnian rings is traditionally believed to be due to resonances caused by Mimas (and possibly other satellites). It is shown that both theoretical and observational evidence rule out this interpretation. The increased observational accuracy on one hand and the increased understanding of the cosmogonic processes on the other makes it possible to explain the structure of the ring system as a product of condensation from a partially corotating plasma. In certain respects the agreement between theory and observations is about 1%. (Auth.)

Ecological approach of macrolide-lincosamides-streptogramin producing actinomyces from Cuban soils.

Science.gov (United States)

González, I; Niebla, A; Lemus, M; González, L; Iznaga, I O; Pérez, M E; Vallin, C

1999-09-01

We report in this study the frequency of Streptomyces strains to produce macrolide-lincosamide-streptogramin (MLS) antibiotics isolated from Cuban soils. The screening assay is based on the induction of MLS-resistance phenotype in a clinical isolated strain of Staphylococcus aureus S-18. Our results suggest that of 800 Streptomyces strains isolated from different soil samples, 6% were positives in the screening test used. The ferralitic red soil from Pinar del Río (north) provided the major percentage (3.6%) of MLS producing strains. The other soil samples tested belonging to Guira de Melena and Bauta in Havana, Matanzas City, Topes De Collantes (Villa Clara), and Soroa Mountains (Pinar del Rio) hill reached very low percentages.

ASSOCIATIVE RINGS SOLVED AS LIE RINGS

Directory of Open Access Journals (Sweden)

M. B. Smirnov

2011-01-01

Full Text Available The paper has proved that an associative ring which is solvable of a n- class as a Lie ring has a nilpotent ideal of the nilpotent class not more than 3×10n–2  and a corresponding quotient ring satisfies an identity [[x1, x2, [x3, x4

Control of ring lasers by means of coupled cavities

DEFF Research Database (Denmark)

Buchhave, Preben; Abitan, Haim; Tidemand-Lichtenberg, Peter

2000-01-01

Variable phase coupling to an external ring is used to control a unidirectional ring laser. The observed behavior of the coupled rings is explained theoretically. We have found experimentally that by quickly changing the phase of the feedback from the external ring it is possible to Q......-switch the ring laser. Also, at certain values of the phase of the feedback in the external ring, instabilities in the total system occur and oscillations arise in the ring laser....

The terminal Eocene event - Formation of a ring system around the earth

Science.gov (United States)

Okeefe, J. A.

1980-01-01

It is suggested that the formation of a ring system about the earth by particles and debris related to the North American strewn tektite field is responsible for the terminal Eocene event of 34 million years ago, in which severe climatic changes accompanied by widespread biological extinctions occurred. Botanical data is cited which implies a 20-C decrease in winter temperature with no change in summer temperature, and evidence of the correlation of the North American tektite fall, which is estimated to have a total mass of 10 to the 9th to 10 to the 10th tons, with the disappearance of five of the most abundant species of radiolaria is presented. The possible connection between the tektites and climatic change is argued to result from the screening of sunlight by an equatorial ring of trapped particles of extraterrestrial origin in geocentric orbit which would cut off sunlight only in the winter months. Such a ring, located at a distance of between 1.5 and 2.5 earth radii (the Roche limit) is estimated to have a lifetime of a few million years.

Non-Linear Dynamics of Saturn's Rings

Science.gov (United States)

Esposito, L. W.

2016-12-01

Non-linear processes can explain why Saturn's rings are so active and dynamic. Ring systems differ from simple linear systems in two significant ways: 1. They are systems of granular material: where particle-to-particle collisions dominate; thus a kinetic, not a fluid description needed. Stresses are strikingly inhomogeneous and fluctuations are large compared to equilibrium. 2. They are strongly forced by resonances: which drive a non-linear response, that push the system across thresholds that lead to persistent states. Some of this non-linearity is captured in a simple Predator-Prey Model: Periodic forcing from the moon causes streamline crowding; This damps the relative velocity. About a quarter phase later, the aggregates stir the system to higher relative velocity and the limit cycle repeats each orbit, with relative velocity ranging from nearly zero to a multiple of the orbit average. Summary of Halo Results: A predator-prey model for ring dynamics produces transient structures like `straw' that can explain the halo morphology and spectroscopy: Cyclic velocity changes cause perturbed regions to reach higher collision speeds at some orbital phases, which preferentially removes small regolith particles; surrounding particles diffuse back too slowly to erase the effect: this gives the halo morphology; this requires energetic collisions (v ≈ 10m/sec, with throw distances about 200km, implying objects of scale R ≈ 20km).Transform to Duffing Eqn : With the coordinate transformation, z = M2/3, the Predator-Prey equations can be combined to form a single second-order differential equation with harmonic resonance forcing.Ring dynamics and history implications: Moon-triggered clumping explains both small and large particles at resonances. We calculate the stationary size distribution using a cell-to-cell mapping procedure that converts the phase-plane trajectories to a Markov chain. Approximating it as an asymmetric random walk with reflecting boundaries

Examining the influence of family environments on youth violence: a comparison of Mexican, Puerto Rican, Cuban, non-Latino Black, and non-Latino White adolescents.

Science.gov (United States)

Estrada-Martínez, Lorena M; Padilla, Mark B; Caldwell, Cleopatra Howard; Schulz, Amy Jo

2011-08-01

Existing research rarely considers important ethnic subgroup variations in violent behaviors among Latino youth. Thus, their risk for severe violent behaviors is not well understood in light of the immense ethnic and generational diversity of the Latino population in the United States. Grounded in social control theory and cultural analyses of familism, we examine differences in the risk for severe youth violence, as well its associations with family cohesion, parental engagement, adolescent autonomy, household composition, and immigrant generation among Mexican (n = 1,594), Puerto Rican (n = 586), Cuban (n = 488), and non-Latino Black (n = 4,053), and White (n = 9,921) adolescents with data from the National Longitudinal Study of Adolescent Health. Results indicate a gradient of risk; White youth had the lowest risk for severe violence and Puerto Rican youth had the highest risk compared to all other racial/ethnic subgroups. Within-group analysis indicates that family factors are not universally protective or risk-inducing. While family cohesion decreased the risk of severe violence among all groups, parental engagement was associated with increased risk among Blacks and Whites, and adolescent autonomy was associated with increased risk among Puerto Ricans and Cubans. In addition, Cuban and White adolescents who lived in single parent households or who did not live with their parents, had higher risk for severe violent behaviors than their counterparts who lived in two parent households. Among Latinos, the association of immigrant generation was in opposite directions among Mexicans and Cubans. We conclude that family and immigration factors differentially influence risk for violence among Latino subgroups and highlight the significance of examining subgroup differences and developing intervention strategies that are tailored to the needs of each ethnic subgroup.

Atmospheric pressure microwave plasma system with ring waveguide

International Nuclear Information System (INIS)

Liu Liang; Zhang Guixin; Zhu Zhijie; Luo Chengmu

2007-01-01

Some scientists used waveguide as the cavity to produce a plasma jet, while large volume microwave plasma was relatively hard to get in atmospheric pressure. However, a few research institutes have already developed devices to generate large volume of atmospheric pressure microwave plasma, such as CYRANNUS and SLAN series, which can be widely applied. In this paper, present a microwave plasma system with ring waveguide to excite large volume of atmospheric pressure microwave plasma, plot curves on theoretical disruption electric field of some working gases, emulate the cavity through software, measure the power density to validate and show the appearance of microwave plasma. At present, large volume of argon and helium plasma have already been generated steadily by atmospheric pressure microwave plasma system. This research can build a theoretical basis of microwave plasma excitation under atmospheric pressure and will be useful in study of the device. (authors)

O rastro do dragão em quatro narradores cubanos The trail of the dragon in four cuban writers

Directory of Open Access Journals (Sweden)

Rogelio Rodríguez Coronel

2013-06-01

Full Text Available Seguindo o rastro da cultura chinesa na cultura e literatura cubanas, este trabalho revela-se como um espaço para a discussão de um tema pouco tratado pela crítica, a presença chinesa na constituição da literatura cubana. O "rastro do dragão" é acompanhado desde o século XVII até a contemporaneidade, passando pela obra de autores como Severo Sarduy, Ramón Meza, José Martí e José Lezama Lima, máximos expoentes da modernidade nas letras em Cuba.Siguiendo las huellas de la cultura china en la cultura y la literatura cubanas, este trabajo se revela como un espacio para la discusión de un tema escasamente tratado por la crítica, la presencia china en la constitución de la literatura cubana. La "huella del dragón" es seguida en este estudio, desde el siglo XVII hasta la contemporaneidad, pasando por la obra de autores como Severo Sarduy, Ramón Meza, José Martí e José Lezama Lima, máximos exponentes de la modernidad de las letras en Cuba.Following the trail of Chinese culture in Cuban culture and literature, the paper discusses the Chinese presence in Cuban literature, a subject seldom covered by literary criticism, "The Trail of the...Dragon" is traced in this study from the XVII Century to the present, covering the work of such writers as Severo Sarduy, Ramón Meza, José Martí and José Lezama Lima, outstanding exponents of modernism in Cuban letters.

Energy spectra of quantum rings.

Science.gov (United States)

Fuhrer, A; Lüscher, S; Ihn, T; Heinzel, T; Ensslin, K; Wegscheider, W; Bichler, M

2001-10-25

Quantum mechanical experiments in ring geometries have long fascinated physicists. Open rings connected to leads, for example, allow the observation of the Aharonov-Bohm effect, one of the best examples of quantum mechanical phase coherence. The phase coherence of electrons travelling through a quantum dot embedded in one arm of an open ring has also been demonstrated. The energy spectra of closed rings have only recently been studied by optical spectroscopy. The prediction that they allow persistent current has been explored in various experiments. Here we report magnetotransport experiments on closed rings in the Coulomb blockade regime. Our experiments show that a microscopic understanding of energy levels, so far limited to few-electron quantum dots, can be extended to a many-electron system. A semiclassical interpretation of our results indicates that electron motion in the rings is governed by regular rather than chaotic motion, an unexplored regime in many-electron quantum dots. This opens a way to experiments where even more complex structures can be investigated at a quantum mechanical level.

Measuring the electron-ion ring parameters by bremsstrahlung

International Nuclear Information System (INIS)

Inkin, V.D.; Mozelev, A.A.; Sarantsev, V.P.

1982-01-01

A system is described for measuring the number of electrons and ions in the electron-ion rings of a collective heavy ion accelerator. The system operation is based on detecting gamma quanta of bremsstrahlung following the ring electron interaction with the nuclei of neutral atoms and ions at different stages of filling the ring with ions. The radiation detector is a scintillation block - a photomultiplier operating for counting with NaI(Tl) crystal sized 30x30 mm and ensuring the detection efficiency close to unity. The system apparatus is made in the CAMAC standard and rems on-line with the TRA/i miniature computer. The block-diagrams of the system and algorithm of data processing are presented. A conclusion is drawn that the results of measuring the ring parameters with the use of the diagnostics system described are in good agreement within the range of measuring errors with those obtained by means of the diagnostics system employing synchrotron radiation and induction sensors

Rings Research in the Next Decade

Science.gov (United States)

Burns, J. A.; Tiscareno, M. S.

2009-12-01

The study of planetary ring systems forms a key component of planetary science for several reasons: 1) The evolution and current states of planets and their satellites are affected in many ways by rings, while 2) conversely, properties of planets and moons and other solar system populations are revealed by their effects on rings; 3) highly structured and apparently delicate ring systems may be bellwethers, constraining various theories of the origin and evolution of their entire planetary system; and finally, 4) planetary rings provide an easily observable analogue to other astrophysical disk systems, enabling real “ground truth” results applicable to disks much more remote in space and/or time, including proto-planetary disks, circum-stellar disks, and even galaxies. Significant advances have been made in rings science in the past decade. The highest-priority rings research recommendations of the last Planetary Science Decadal Survey were to operate and extend the Cassini orbiter mission at Saturn; this has been done with tremendous success, accounting for much of the progress made on key science questions, as we will describe. Important progress in understanding the rings of Saturn and other planets has also come from Earth-based observational and theoretical work, again as prioritized by the last Decadal Survey. However, much important work remains to be done. At Saturn, the Cassini Solstice Mission must be brought to a successful completion. Priority should also be placed on sending spacecraft to Neptune and/or Uranus, now unvisited for more than 20 years. At Jupiter and Pluto, opportunities afforded by visiting spacecraft capable of studying rings should be exploited. On Earth, the need for continued research and analysis remains strong, including in-depth analysis of rings data already obtained, numerical and theoretical modeling work, laboratory analysis of materials and processes analogous to those found in the outer solar system, and continued Earth

Oxygen-atom transfer chemistry and thermolytic properties of a di-tert-butylphosphate-ligated Mn4O4 cubane.

Science.gov (United States)

Van Allsburg, Kurt M; Anzenberg, Eitan; Drisdell, Walter S; Yano, Junko; Tilley, T Don

2015-03-16

[Mn4O4{O2P(OtBu)2}6] (1), an Mn4O4 cubane complex combining the structural inspiration of the photosystem II oxygen-evolving complex with thermolytic precursor ligands, was synthesized and fully characterized. Core oxygen atoms within complex 1 are transferred upon reaction with an oxygen-atom acceptor (PEt3), to give the butterfly complex [Mn4O2{O2P(OtBu)2}6(OPEt3)2]. The cubane structure is restored by reaction of the latter complex with the O-atom donor PhIO. Complex 1 was investigated as a precursor to inorganic Mn metaphosphate/pyrophosphate materials, which were studied by X-ray absorption spectroscopy to determine the fate of the Mn4O4 unit. Under the conditions employed, thermolyses of 1 result in reduction of the manganese to Mn(II) species. Finally, the related butterfly complex [Mn4O2{O2P(pin)}6(bpy)2] (pin = pinacolate) is described. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Structural and magnetic characterization of three tetranuclear Cu(II) complexes with face-sharing-dicubane/double-open-cubane like core framework

Science.gov (United States)

Paul, Aparup; Bertolasi, Valerio; Figuerola, Albert; Manna, Subal Chandra

2017-05-01

Three novel tetranuclear copper(II) complexes namely [Cu4(L1)4]•2(dmf) (1), [Cu4(L1)4] (2) and [Cu4(L2)2(HL2)2(H2O)2]•2(ClO4)·6(H2O) (3) (H2L1, (E)-2-((1-hydroxybutan-2-ylimino)methyl)phenol; H2L2, (E)-2-((1-hydroxybutan-2-ylimino)methyl)-6-methoxyphenol)) were synthesized from the self-assembly of copper(II) perchlorate and the tridentate Schiff base ligands. The structural determination reveals that complex 1 crystallizes in the monoclinic system with space group C2/c, whereas both the complexes 2 and 3 crystallize in the triclinic system with space group P-1. Complexes 1 and 2 possess face-sharing dicubane core, on the other hand complex 3 has double open cubane core structure. The copper(II) ions in the cubane core are in distorted square planar geometries, and weak π…π and C-H…π interactions lead to formation of a 2D supramolecular architecture for complexes 1 and 2. At room temperature complexes 1, 2 and 3, exhibit fluorescence with a quantum yield (Φs) of 0.47, 0.49 and 0.38, respectively. Variable temperature magnetic susceptibility measurements in the range 2-300 K indicate an overall weak antiferromagnetic exchange coupling in all complexes. The PHI program was used to study their magnetic behaviour. In agreement with their face-sharing dicubane structure, a Hamiltonian of the type H =- J1(S1S2+S1S2'+S1'S2+S1'S2') - J2S1S1', where S1 = S1' = S2 = S2' = SCu =1/2, was used for studying complexes 1 and 2. Simulations performed suggest magnetic exchange constants with values close to J1 =-20 cm-1 and J2 =0 cm-1 for these complexes. On the other hand, the spin Hamiltonian H =- J1(S1S4+S2S3) - J2(S1S3+S2S4) - J3S1S2, where S1 = S2 = S3 = S4 = SCu =1/2, was used to study the magnetic behaviour of the double open cubane core of complex 3 and a good agreement between the experimental and simulated results was found by using the parameters g1 = g2 =2.20, g3 = g4 =2.18, J1 =-36 cm-1, J2 =-44 cm-1 and J3 =0 cm-1.

Ground Movement in SSRL Ring

International Nuclear Information System (INIS)

Sunikumar, Nikita

2011-01-01

Users of the Stanford Synchrotron Radiation Lightsource (SSRL) are being affected by diurnal motion of the synchrotron's storage ring, which undergoes structural changes due to outdoor temperature fluctuations. In order to minimize the effects of diurnal temperature fluctuations, especially on the vertical motion of the ring floor, scientists at SSRL tried three approaches: painting the storage ring white, covering the asphalt in the middle of the ring with highly reflective Mylar and installing Mylar on a portion of the ring roof and walls. Vertical motion in the storage ring is measured by a Hydrostatic Leveling System (HLS), which calculates the relative height of water in a pipe that extends around the ring. The 24-hr amplitude of the floor motion was determined using spectral analysis of HLS data, and the ratio of this amplitude before and after each experiment was used to quantitatively determine the efficacy of each approach. The results of this analysis showed that the Mylar did not have any significant effect on floor motion, although the whitewash project did yield a reduction in overall HLS variation of 15 percent. However, further analysis showed that the reduction can largely be attributed to a few local changes rather than an overall reduction in floor motion around the ring. Future work will consist of identifying and selectively insulating these local regions in order to find the driving force behind diurnal floor motion in the storage ring.

Non-Linear Dynamics of Saturn’s Rings

Science.gov (United States)

Esposito, Larry W.

2015-11-01

Non-linear processes can explain why Saturn’s rings are so active and dynamic. Ring systems differ from simple linear systems in two significant ways: 1. They are systems of granular material: where particle-to-particle collisions dominate; thus a kinetic, not a fluid description needed. We find that stresses are strikingly inhomogeneous and fluctuations are large compared to equilibrium. 2. They are strongly forced by resonances: which drive a non-linear response, pushing the system across thresholds that lead to persistent states.Some of this non-linearity is captured in a simple Predator-Prey Model: Periodic forcing from the moon causes streamline crowding; This damps the relative velocity, and allows aggregates to grow. About a quarter phase later, the aggregates stir the system to higher relative velocity and the limit cycle repeats each orbit.Summary of Halo Results: A predator-prey model for ring dynamics produces transient structures like ‘straw’ that can explain the halo structure and spectroscopy: This requires energetic collisions (v ≈ 10m/sec, with throw distances about 200km, implying objects of scale R ≈ 20km).Transform to Duffing Eqn : With the coordinate transformation, z = M2/3, the Predator-Prey equations can be combined to form a single second-order differential equation with harmonic resonance forcing.Ring dynamics and history implications: Moon-triggered clumping at perturbed regions in Saturn’s rings creates both high velocity dispersion and large aggregates at these distances, explaining both small and large particles observed there. We calculate the stationary size distribution using a cell-to-cell mapping procedure that converts the phase-plane trajectories to a Markov chain. Approximating the Markov chain as an asymmetric random walk with reflecting boundaries allows us to determine the power law index from results of numerical simulations in the tidal environment surrounding Saturn. Aggregates can explain many dynamic aspects

RF-to-RF Characterization of a Phased Array Receive Antenna Steering System Using a Novel Ring Resonator-Based Integrated Photonic Beamformer

NARCIS (Netherlands)

Zhuang, L.; Burla, M.; Roeloffzen, C.G.H.; Meijerink, Arjan; Marpaung, D.A.I.; Khan, M.R.H.; van Etten, Wim; Leinse, Arne; Hoekman, M.; Heideman, Rene

2009-01-01

A novel ring resonator-based photonic beamformer has been developed for continuous and squint-free control of the reception angle of broadband phased array antenna systems. The core of the system is a ring resonator based optical beamforming network (OBFN) used for delay synchronization and coherent

Mapping Ring Particle Cooling across Saturn's Rings with Cassini CIRS

Science.gov (United States)

Brooks, Shawn M.; Spilker, L. J.; Edgington, S. G.; Pilorz, S. H.; Deau, E.

2010-10-01

Previous studies have shown that the rings' thermal inertia, a measure of their response to changes in the thermal environment, varies from ring to ring. Thermal inertia can provide insight into the physical structure of Saturn's ring particles and their regoliths. Low thermal inertia and quick temperature responses are suggestive of ring particles that have more porous or fluffy regoliths or that are riddled with cracks. Solid, coherent particles can be expected to have higher thermal inertias (Ferrari et al. 2005). Cassini's Composite Infrared Spectrometer has recorded millions of spectra of Saturn's rings since its arrival at Saturn in 2004 (personal communication, M. Segura). CIRS records far infrared radiation between 10 and 600 cm-1 (16.7 and 1000 µm) at focal plane 1 (FP1), which has a field of view of 3.9 mrad. Thermal emission from Saturn's rings peaks in this wavelength range. FP1 spectra can be used to infer ring temperatures. By tracking how ring temperatures vary, we can determine the thermal inertia of the rings. In this work we focus on CIRS observations of the shadowed portion of Saturn's rings. The thermal budget of the rings is dominated by the solar radiation absorbed by its constituent particles. When ring particles enter Saturn's shadow this source of energy is abruptly cut off. As a result, ring particles cool as they traverse Saturn's shadow. From these shadow observations we can create cooling curves at specific locations across the rings. We will show that the rings' cooling curves and thus their thermal inertia vary not only from ring to ring, but by location within the individual rings. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Copyright 2010 California Institute of Technology. Government sponsorship acknowledged.

Perspectives for Distributed Observations of Near-Earth Space Using a Russian-Cuban Observatory

Science.gov (United States)

Bisikalo, D. V.; Savanov, I. S.; Naroenkov, S. A.; Nalivkin, M. A.; Shugarov, A. S.; Bakhtigaraev, N. S.; Levkina, P. A.; Ibragimov, M. A.; Kil'pio, E. Yu.; Sachkov, M. E.; Kartashova, A. P.; Fateeva, A. M.; Uratsuka, Marta R. Rodriguez; Estrada, Ramses Zaldivar; Diaz, Antonio Alonsa; Rodríguez, Omar Pons; Figuera, Fidel Hernandes; Garcia, Maritza Garcia

2018-06-01

The creation of a specialized network of large, wide-angle telescopes for distributed observations of near-Earth space using a Russian-Cuban Observatory is considered. An extremely important goal of routine monitoring of near-Earth and near-Sun space is warding off threats with both natural and technogenic origins. Natural threats are associated with asteroids or comets, and technogenic threats with man-made debris in near-Earth space. A modern network of ground-based optical instruments designed to ward off such threats must: (a) have a global and, if possible, uniform geographic distribution, (b) be suitable for wide-angle, high-accuracy precision survey observations, and (c) be created and operated within a single network-oriented framework. Experience at the Institute of Astronomy on the development of one-meter-class wide-angle telescopes and elements of a super-wide-angle telescope cluster is applied to determine preferences for the composition of each node of such a network. The efficiency of distributed observations in attaining maximally accurate predictions of the motions of potentially dangerous celestial bodies as they approach the Earth and in observations of space debris and man-made satellites is estimated. The first estimates of astroclimatic conditions at the proposed site of the future Russian-Cuban Observatory in the mountains of the Sierra del Rosario Biosphere Reserve are obtained. Special attention is given to the possible use of the network to carry out a wide range of astrophysical studies, including optical support for the localization of gravitational waves and other transient events.

MATLAB based beam orbit correction system of HLS storage ring

International Nuclear Information System (INIS)

Ding Shichuan; Liu Gongfa; Xuan Ke; Li Weimin; Wang Lin; Wang Jigang; Li Chuan; Bao Xun; Guo Weiqun

2006-01-01

The distortion of closed orbit usually causes much side effect which is harmful to synchrotron radiation source such as HLS, so it is necessary to correct the distortion of closed orbit. In this paper, the correction principle, development procedure and test of MATLAB based on beam orbit correction system of HLS storage ring are described. The correction system is consisted of the beam orbit measure system, corrector magnet system and the control system, and the beam orbit correction code based on MATLAB is working on the operation interface. The data of the beam orbit are analyzed and calculated firstly, and then the orbit is corrected by changing corrector strength via control system. The test shows that the distortion of closed orbit is from max 4.468 mm before correction to max 0.299 mm after correction as well as SDEV is from 2.986 mm to 0.087 mm. So the correction system reaches the design goal. (authors)

A reachability test for systems over polynomial rings using Gröbner bases

NARCIS (Netherlands)

Habets, L.C.G.J.M.

1992-01-01

Conditions for the reachability of a system over a polynomial ring are well known in the literature. However, the verification of these conditions remained a difficult problem in general. Application of the Gröbner Basis method from constructive commutative algebra makes it possible to carry out

Stabilization of Reduced Molybdenum-Iron-Sulfur Single and Double Cubane Clusters by Cyanide Ligation

Science.gov (United States)

Pesavento, Russell P.; Berlinguette, Curtis P.; Holm, R. H.

2008-01-01

Recent work has shown that cyanide ligation increases the redox potentials of Fe4S4 clusters, enabling the isolation of [Fe4S4(CN)4]4−, the first synthetic Fe4S4 cluster obtained in the all-ferrous oxidation state (Scott, T. A.; Berlinguette, C. P.; Holm, R. H.; Zhou, H.-C., Proc. Natl. Acad. Sci. USA 2005, 102, 9741). The generality of reduced cluster stabilization has been examined with MoFe3S4 clusters. Reaction of single cubane [(Tp)MoFe3S4(PEt3)3]1+ and edge-bridged double cubane [(Tp)2Mo2Fe6S8(PEt3)4] with cyanide in acetonitrile affords [(Tp)MoFe3S4(CN)3]2− (2) and [(Tp)2Mo2Fe6S8(CN)4]4− (5), respectively. Reduction of 2 with KC14H10 yields [(Tp)MoFe3S4(CN)3]3− (3). Clusters were isolated in ca. 70–90% yields as Et4N+ or Bu4N+ salts; Clusters 3 and 5 contain all-ferrous cores; 3 is the first [MoFe3S4]1+ cluster isolated in substance. The structures of 2 and 3 are very similar; the volume of the reduced cluster core is slightly larger (2.5%), a usual effect upon reduction of cubane-type Fe4S4 and MFe3S4 clusters. Redox potentials and 57Fe isomer shifts of [(Tp)MoFe3S4L3]2−,3 and [(Tp)2Mo2Fe6S8L4]4−,3− clusters with L = CN, PhS, halide, and PEt3 are compared. Clusters with π-donor ligands (L = halide, PhS) exhibit larger isomer shifts and lower (more negative) redox potentials while π-acceptor ligands (L = CN, PEt3) induce smaller isomer shifts and higher (less negative) redox potentials. When potentials of 3/2 and [(Tp)MoFe3S4(SPh)3]3−/2− are compared, cyanide stabilizes 3 by 270 mV vs. the reduced thiolate cluster, commensurate with the 310 mV stabilization of [Fe4S4(CN)4]4− vs. [Fe4S4(SPh)4]4− where four ligands differ. These results demonstrate the efficacy of cyanide stabilization of lower cluster oxidation states. (Tp = hydrotris(pyrazolyl)borate(1−)). PMID:17279830

Stabilization of reduced molybdenum-iron-sulfur single- and double-cubane clusters by cyanide ligation.

Science.gov (United States)

Pesavento, Russell P; Berlinguette, Curtis P; Holm, R H

2007-01-22

Recent work has shown that cyanide ligation increases the redox potentials of Fe(4)S(4) clusters, enabling the isolation of [Fe(4)S(4)(CN)4]4-, the first synthetic Fe(4)S(4) cluster obtained in the all-ferrous oxidation state (Scott, T. A.; Berlinguette, C. P.; Holm, R. H.; Zhou, H.-C. Proc. Natl. Acad. Sci. U.S.A. 2005, 102, 9741). The generality of reduced cluster stabilization has been examined with MoFe(3)S(4) clusters. Reaction of single-cubane [(Tp)MoFe(3)S(4)(PEt(3))3]1+ and edge-bridged double-cubane [(Tp)2Mo(2)Fe(6)S(8)(PEt(3))4] with cyanide in acetonitrile affords [(Tp)MoFe(3)S(4)(CN)3]2- (2) and [(Tp)2Mo(2)Fe(6)S(8)(CN)4]4- (5), respectively. Reduction of 2 with KC(14)H(10) yields [(Tp)MoFe(3)S(4)(CN)3]3- (3). Clusters were isolated in approximately 70-90% yields as Et(4)N+ or Bu(4)N+ salts; clusters 3 and 5 contain all-ferrous cores, and 3 is the first [MoFe(3)S(4)]1+ cluster isolated in substance. The structures of 2 and 3 are very similar; the volume of the reduced cluster core is slightly larger (2.5%), a usual effect upon reduction of cubane-type Fe(4)S(4) and MFe(3)S(4) clusters. Redox potentials and 57Fe isomer shifts of [(Tp)MoFe(3)S(4)L3]2-,3- and [(Tp)2Mo(2)Fe(6)S(8)L(4)]4-,3- clusters with L = CN-, PhS-, halide, and PEt3 are compared. Clusters with pi-donor ligands (L = halide, PhS) exhibit larger isomer shifts and lower (more negative) redox potentials, while pi-acceptor ligands (L = CN, PEt3) induce smaller isomer shifts and higher (less-negative) redox potentials. When the potentials of 3/2 and [(Tp)MoFe(3)S(4)(SPh)3]3-/2- are compared, cyanide stabilizes 3 by 270 mV versus the reduced thiolate cluster, commensurate with the 310 mV stabilization of [Fe(4)S(4)(CN)4]4- versus [Fe(4)S(4)(SPh)4]4- where four ligands differ. These results demonstrate the efficacy of cyanide stabilization of lower cluster oxidation states. (Tp = hydrotris(pyrazolyl)borate(1-)).

The Cuban experience in public health: does political will have a role?

Science.gov (United States)

Pagliccia, Nino; Alvarez Pérez, Adolfo

2012-01-01

The role of political will in public health has been largely ignored. In Cuba, however, for the past 50 years, political will has been the ultimate, encompassing intersectoral action in public health. The excellent achievements in population health in Cuba during these 50 years have been widely recognized. Researchers have sought to explain this "Cuban paradox" by focusing on a large array of public health factors, including health promotion, primary care activities, and intersectoral action on health determinants. These factors constitute necessary but not sufficient conditions to achieve good health outcomes. This article defines political will and uses the experience of Cuba to illustrate the potential role of political will in public health. The authors suggest a framework for the evaluation of political will aimed at achieving good health, examining the "Five R's of political will," five observable features that may provide systematic information on the direction and realization of political will: (1) renewal of commitment, (2) reform of the system, (3) resource development, (4) review of performance, and (5) responsible management. These five features focus the spotlight on the consistency between health goals and public discourse and action.

Ring Avulsion Injuries: A Systematic Review.

Science.gov (United States)

Bamba, Ravinder; Malhotra, Gautam; Bueno, Reuben A; Thayer, Wesley P; Shack, R Bruce

2018-01-01

Ring avulsion injuries can range from soft tissue injury to complete amputation. Grading systems have been developed to guide treatment, but there is controversy with high-grade injuries. Traditionally, advanced ring injuries have been treated with completion amputation, but there is evidence that severe ring injuries can be salvaged. The purpose of this systematic review was to pool the current published data on ring injuries. A systematic review of the English literature published from 1980 to 2015 in PubMed and MEDLINE databases was conducted to identify patients who underwent treatment for ring avulsion injuries. Twenty studies of ring avulsion injuries met the inclusion criteria. There were a total of 572 patients reported with ring avulsion injuries. The Urbaniak class breakdown was class I (54 patients), class II (204 patients), and class III (314 patients). The average total arc of motion (TAM) for patients with a class I injury was 201.25 (n = 40). The average 2-point discrimination was 5.6 (n = 10). The average TAM for patients with a class II injury undergoing microsurgical revascularization was 187.0 (n = 114), and the average 2-point discrimination was 8.3 (n = 40). The average TAM for patients with a class III injury undergoing microsurgical revascularization was 168.2 (n = 170), and the average 2-point discrimination was 10.5 (n = 97). Ring avulsion injuries are commonly classified with the Urbaniak class system. Outcomes are superior for class I and II injuries, and there are select class III injuries that can be treated with replantation. Shared decision making with patients is imperative to determine whether replantation is appropriate.

The Ring System of Saturn as Seen by Cassini-VIMS (Invited)

Science.gov (United States)

Filacchione, G.; Ciarniello, M.; Capaccioni, F.

2015-08-01

Since 2004 the Visual and Infrared Mapping Spectrometer (VIMS) aboard Cassini has acquired numerous hyperspectral mosaics in the 0.35-5.1 μm spectral range of Saturn's main rings in very different illumination and viewing geometries. These observations have allowed us to infer the ring particles physical properties and composition: water ice abundance is estimated through the 1.25-1.5-2.0 μm band depths, chromophores distribution is derived from visible spectral slopes while organic material is traced by the aliphatic compounds signature at 3.42 μm which appears stronger on CD and C ring than on A-B rings (Filacchione et al., 2014). Observed reflectance spectra are fitted with a spectrophotometric model based on Montecarlo ray-tracing with the scope to infer particles composition while disentangling photometric effects (caused by multiple scattering, opposition surge and forward scattering) which depend on illumination/viewing geometries. Spectral bond albedo for different regions of the rings has been best-fitted using Hapke's radiative transfer modeling (Ciarniello et al, 2011) by choosing different mixtures of water ice, tholin, and amorphous carbon particles populations. While tholin distribution seems to be fairly constant across the rings, the amorphous carbon appears anti-correlated with optical depth. Moreover, dark material contamination is less effective on densest regions, where the more intense rejuvenation processes occur, in agreement with the ballistic transport theory (Cuzzi and Estrada,1998). Finally, the 3.6 μm continuum peak wavelength is used to infer particles temperature, which is anti-correlated with the albedo and the optical depth (tau): low-albedo/low-tau C ring and CD have higher temperatures than A-B rings where albedo and tau are high. This trend matches direct temperature measurements by CIRS (Spilker et al., 2013).

Strengthening the Radiation Protection System in Cuba (SRPS - Cuba). A co-operation project between Cuban and Swedish institutions, February 2001 - June 2003

International Nuclear Information System (INIS)

Avila, Rodolfo; Larsson, Carl-Magnus; Prendes, Miguel; Zerquera, Juan Tomas

2004-02-01

This project results from the co-operation between a number of Cuban and Swedish institutions. It started in February 2001 and ended in June 2003 and was made possible thanks to the contributions of the Swedish International Development Co-operation Agency (SIDA), the Centro de Proteccion e Higiene de las Radiaciones, Cuba (CPHR), and the Swedish Radiation Protection Authority (SSI). The overall objective was to strengthen the radiation protection system in Cuba, and in this way contribute with the control and reduction of risks to man and the environment from exposures to ionizing radiation. The project focused on four priority areas: 1) Protection of workers and patients exposed to radiation in radiation practices; 2) Preparedness for response to an emergency situation; 3) Environmental radiological protection; and, 4) Exposure to radiation in areas with high levels of natural radioactivity. The present report summarizes the findings of the whole project period, providing an overview of the overall achievements, as well as listing its deliverables. The results of an evaluation of the project, conducted during the final workshop, are also included. The report ends with a list of generic and specific conclusions and recommendations for implementation of the project's achievements and for further development of co-operation

Strengthening the Radiation Protection System in Cuba (SRPS - Cuba). A co-operation project between Cuban and Swedish institutions, February 2001 - June 2003

Energy Technology Data Exchange (ETDEWEB)

Avila, Rodolfo; Larsson, Carl-Magnus; Prendes, Miguel; Zerquera, Juan Tomas

2004-02-01

This project results from the co-operation between a number of Cuban and Swedish institutions. It started in February 2001 and ended in June 2003 and was made possible thanks to the contributions of the Swedish International Development Co-operation Agency (SIDA), the Centro de Proteccion e Higiene de las Radiaciones, Cuba (CPHR), and the Swedish Radiation Protection Authority (SSI). The overall objective was to strengthen the radiation protection system in Cuba, and in this way contribute with the control and reduction of risks to man and the environment from exposures to ionizing radiation. The project focused on four priority areas: 1) Protection of workers and patients exposed to radiation in radiation practices; 2) Preparedness for response to an emergency situation; 3) Environmental radiological protection; and, 4) Exposure to radiation in areas with high levels of natural radioactivity. The present report summarizes the findings of the whole project period, providing an overview of the overall achievements, as well as listing its deliverables. The results of an evaluation of the project, conducted during the final workshop, are also included. The report ends with a list of generic and specific conclusions and recommendations for implementation of the project's achievements and for further development of co-operation.

Transformation of Zwitterionic Pyridine Derivatives to a Spiro-Fused Ring System: Azoniabenzo[de]fluorine. Synthesis and Mechanistic Rationalization.

Science.gov (United States)

Palkó, Roberta; Egyed, Orsolya; Rokob, Tibor András; Bombicz, Petra; Riedl, Zsuzsanna; Hajós, György

2015-01-02

Reaction of aryl- and benzylsulfanopyridinium amidates bearing a methyl group in position 6 with 2 equiv of diphenylketene afforded a spiro-fused ring system: azoniabenzo[de]fluorine. By use of an excess amount of ketene, a distinct reaction was observed via which a 1H-pyrrolo[3,2-b]pyridin-2(3H)-one derivative was furnished. The structure of the tetracyclic spiro-fused ring system was unambiguously confirmed by X-ray diffraction, and its formation was rationalized by DFT calculations.

Use of neuronal networks in the modeling of the doses that receives the Cuban population by potassium-40 contained in their organism

International Nuclear Information System (INIS)

Zerquera, Juan Tomas; Prendes Alonso, Miguel; Lopez Bejerano, Gladys M.; Acosta Rodriguez, Nancy

2001-01-01

The potassium 40 constitutes the main source natural present in the organism that influences in the effective dose that people receive. With the objective of evaluating the contribution from this component to the doses received by the Cuban population, a study was developed in order to evaluate the doses for this cause. A representative sample was selected based on the distribution of Cuban population by sex and ages. The measurements were carried out in the Whole Body Counter of the Center for Radiation Protection and Hygiene. For the estimate of the doses an uniform distribution of potassium was assumed in the whole body and the methodology was used recommended by the ICRP. The values of annual effective dose varies between 93 and 209 mSv for the feminine sex and 102 and 212 mSv for the masculine sex. With the obtained values they were the adjustment coefficients for the functions dose-age for each one of the sexes. At the same time it was possible to model the estimate of the doses by means of a neural network that, trained with the obtained experimental data, it allows to estimate the due doses directly to the potassium 40 starting from the sex data, age, height and corporal weight. The effective dose mediates yearly for the public's members it was estimated in 149 ± 6 mSv, starting from the experimental data and the Cuban population's specific characteristics. (author)

Reflective variable optical attenuators and fibre ring lasers for wavelength-division multiplexing systems

Science.gov (United States)

Liu, He Liang

Wavelength division multiplexing (WDM) optical fibre system is an important enabling technology to fulfill the demands for bandwidth in the modern information age. The main objective of this project is to study novel devices with the potential to enhance the performance of WDM systems. In particular, a novel reflective variable optical attenuator (RVOA) used for dynamic gain equalization (DGE) and fibre lasers based on an entirely new type of erbium-doped fibres with ultrawide tuning range were investigated theoretically and experimentally. We proposed a new type of RVOA device which could be potentially integrated with arrayed waveguide grating (AWG) to reduce the cost of DGE substantially. Initially, fibre-based RVOAs, fabricated with optical fibre components such as fibre coupler and Faraday rotator mirror, were investigated theoretically and experimentally. Larger attenuation range up to 22 dB was realized for fibre coupler-based ROVA with a Faraday rotator mirror and its polarization-dependent loss is about 0.5 dB. Then polymeric waveguide-based RVOAs were investigated theoretically and experimentally. Using an epoxy Novolak resin as core material and an UV-cured resin (Norland's NOA61) as cladding material, a polymeric waveguide RVOA was successfully fabricated. The dynamic 15 dB attenuation range was achieved and the PDL was less than 0.2 dB. The measured insertion loss of the polymeric waveguide RVOA was too large (about 18 dB) and was mainly induced by coupling loss, material loss and poor alignment. In the second part of the study, fibre ring lasers with continuous wavelength tuning over wide wavelength range and fibre ring lasers with discrete wavelength tuning were investigated. Tunable lasers are important devices in WDM systems because they could be employed as reserved sources and therefore avoiding the need to stock large inventory of lasers to cover the ITU-wavelength grid. In this project, erbium ions doped bismuth oxide glass fibres instead of

The solar energy photovoltaic one option to the Cuban rural electrification

Energy Technology Data Exchange (ETDEWEB)

Alabart, J. A. [Centro de Investigaciones de Energia Solar (CIES), (Cuba); Friedman, D. [ECOSOL (COPEXTELL S. A.), (Cuba); Ramos, R.; Moreira, J.; Batista, I.; Garcia, R.; Rodriguez, M. [Centro de Investigaciones de Energia Solar (CIES), (Cuba)

1995-12-31

This paper analyzes the work done in Cuba over the last years in the field of photovoltaic, from its R and D and Industrial capacities to the Rural Electrification Program. Based on this work a Development Program for the PV industry is proposed, which is defected towards the integration of all necessary factors that will ensure a sustainable Rural Electrification Program. This program is divided in 5 main stages: 1. Import of solar cells and other elements for the assembly in Cuba of modules and diverse system components (1995-2005). 2. Production of solar cells from imported wafers (1997-2005). 3. Production of monocrystalline silicon wafers from imported plycrystalline silicon (1998-2005). 4. Production of polycrystalline silicon from Cuban silica sand (2000-2005). 5. Development and introduction of new technologies for the production of solar cells (2000-2005). The combination of the PV Development program and the Rural Electrification program will guarantee the supply of electricity to 100% of the Cuban population, and at same time accelerate the technological, industrial and research infrastructure on which a large scale national PV industry would be supported. The implementation of such a program would also make cost on the National Electrical Grid (NEG), avoiding the need for new generation facilities based on fossil fuels. [Espanol] Este articulo analiza el trabajo hecho en Cuba durante los ultimos anos en el campo de los fotovoltaicos, desde su Investigacion y Desarrollo y capacidades Industriales, hasta el Programa de Electrificacion Rural. Basado en este trabajo se propone un Programa de Desarrollo para la industria de PV que esta dirigido hacia la integracion de todos los factores necesarios que aseguraran un Programa de Electrificacion sostenido. Este programa esta dividido en 5 principales etapas: 1. Importacion de celdas solares y otros elementos para el ensamblado en Cuba de modulos y diversos componentes del sistema (1995-2005); 2. Produccion de

The solar energy photovoltaic one option to the Cuban rural electrification

Energy Technology Data Exchange (ETDEWEB)

Alabart, J A [Centro de Investigaciones de Energia Solar (CIES), (Cuba); Friedman, D [ECOSOL (COPEXTELL S. A.), (Cuba); Ramos, R; Moreira, J; Batista, I; Garcia, R; Rodriguez, M [Centro de Investigaciones de Energia Solar (CIES), (Cuba)

1996-12-31

This paper analyzes the work done in Cuba over the last years in the field of photovoltaic, from its R and D and Industrial capacities to the Rural Electrification Program. Based on this work a Development Program for the PV industry is proposed, which is defected towards the integration of all necessary factors that will ensure a sustainable Rural Electrification Program. This program is divided in 5 main stages: 1. Import of solar cells and other elements for the assembly in Cuba of modules and diverse system components (1995-2005). 2. Production of solar cells from imported wafers (1997-2005). 3. Production of monocrystalline silicon wafers from imported plycrystalline silicon (1998-2005). 4. Production of polycrystalline silicon from Cuban silica sand (2000-2005). 5. Development and introduction of new technologies for the production of solar cells (2000-2005). The combination of the PV Development program and the Rural Electrification program will guarantee the supply of electricity to 100% of the Cuban population, and at same time accelerate the technological, industrial and research infrastructure on which a large scale national PV industry would be supported. The implementation of such a program would also make cost on the National Electrical Grid (NEG), avoiding the need for new generation facilities based on fossil fuels. [Espanol] Este articulo analiza el trabajo hecho en Cuba durante los ultimos anos en el campo de los fotovoltaicos, desde su Investigacion y Desarrollo y capacidades Industriales, hasta el Programa de Electrificacion Rural. Basado en este trabajo se propone un Programa de Desarrollo para la industria de PV que esta dirigido hacia la integracion de todos los factores necesarios que aseguraran un Programa de Electrificacion sostenido. Este programa esta dividido en 5 principales etapas: 1. Importacion de celdas solares y otros elementos para el ensamblado en Cuba de modulos y diversos componentes del sistema (1995-2005); 2. Produccion de

Component and system tests of the SLD Cerenkov Ring Imaging Detector

International Nuclear Information System (INIS)

Antilogus, P.; Bird, F.; Aston, D.; Dasu, S.; Dunwoodie, W.; Hallewell, G.; Kawahara, H.; Kwon, Y.; Leith, D.; Nagamine, T.; Pavel, T.; Muller, D.; Williams, S.; Bienz, T.; Dolinsky, S.; Solodov, E.; Coyle, P.; Cavalli-Sforza, M.; Coyne, D.; Gagnon, P.; Liu, X.; Williams, D.A.

1990-01-01

The components of the SLD barrel Cerenkov Ring Imaging Detector (CRID) are now built and are being installed. This paper reports on tests of these components, including tests of the fiber optic calibration system, detailed studies of electron drift paths on production drift boxes and detectors, tests of the dynamic gating system and its effect on drift path distortions due to space-charge, and a measurement of the electron lifetime in a production drift box. In addition, the authors report on the UV transmission of recirculated liquid freon and on the effects of CRID construction materials on electron lifetime

Component and system tests of the SLD Cerenkov Ring Imaging Detector

International Nuclear Information System (INIS)

Antilogus, P.; Aston, D.; Bienz, T.; Bird, F.; Dasu, S.; Dolinsky, S.; Dunwoodie, W.; Hallewell, G.; Kawahara, H.; Kwon, Y.; Leith, D.; Muller, D.; Nagamine, T.; Pavel, T.; Ratcliff, B.; Rensing, P.; Schultz, D.; Shapiro, S.; Simopoulos, C.; Solodov, E.; Toge, N.; Va'vra, J.; Williams, S.; Cavalli-Sforza, M.; Coyle, P.; Coyne, D.; Gagnon, P.; Liu, X.; Williams, D.A.; Whitaker, J.S.; Wilson, R.J.; Bean, A.; Caldwell, D.; Duboscq, J.; Huber, J.; Lu, A.; Mathys, L.; McHugh, S.; Witherell, M.; Yellin, S.; D'Oliveira, A.; Johnson, R.A.; Martinez, J.L.; Meadows, B.; Nussbaum, M.; Santha, A.K.S.; Shoup, A.; Stockdale, I.; Baird, K.; Jacques, P.; Kalelkar, M.; Plano, R.; Stamer, P.; Word, G.; Abe, K.; Hasegawa, K.; Suekane, F.; Yuta, H.

1991-02-01

The components of the SLD barrel Cerenkov Ring Imaging Detector (CRID) are now built and are being installed. We report on tests of these, including tests of the fiber optic calibration system, detailed studies of electron drift paths on production drift boxes and detectors, tests of the dynamic gating system and its effect on drift path distortions due to space-charge, and a measurement of the electron lifetime in a production drift box. In addition, we report on the UV transmission of recirculated liquid C 6 F 14 and on the effects of CRID construction materials on electron lifetime. 9 refs., 11 figs

Component and system tests of the SLD Cerenkov Ring Imaging Detector

International Nuclear Information System (INIS)

Antilogus, P.; Aston, D.; Bienz, T.; Bird, F.; Dasu, S.; Dolinsky, S.; Dunwoodie, W.; Hallewell, G.; Kawahara, H.; Kwon, Y.; Leith, D.; Muller, D.; Nagamine, T.; Pavel, T.; Ratcliff, B.; Rensing, P.; Schultz, D.; Shapiro, S.; Simopoulos, C.; Solodov, E.; Toge, N.; Va'vra, J.; Williams, S.; Cavalli-Sforza, M.; Coyle, P.; Coyne, D.; Gagnon, P.; Liu, X.; Williams, D.A.; Whitaker, J.S.; Wilson, R.J.; Bean, A.; Caldwell, D.; Duboscq, J.; Huber, J.; Lu, A.; Mathys, L.; McHugh, S.; Witherell, M.; Yellin, S.; d'Oliveira, A.; Johnson, R.A.; Martinez, J.; Meadows, B.; Nussbaum, M.; Santha, A.K.S.; Shoup, A.; Stockdale, I.; Jacques, P.; Kalelkar, M.; Plano, R.; Stamer, P.; Abe, K.; Hasegawa, K.; Suekane, F.; Yuta, H.

1990-10-01

The components of the SLD barrel Cerenkov Ring Imaging Detector (CRID) are now built and are being installed. We report on tests of these components, including tests of the fiber optic calibration system, detailed studies of electron drift paths on production drift boxes and detectors, tests of the dynamic gating systems and its effect on drift path distortions due to space-charge, and a measurement of the electron lifetime in a production drift box. In addition, we report on the UV transmission of recirculated liquid freon and on the effects of CRID construction materials on electron lifetime. 16 refs., 12 figs

Facebook social uses by young Cubans on the island

Directory of Open Access Journals (Sweden)

Liliam Marrero Santana

2017-10-01

Full Text Available It proposes an approach to the social uses of the social networking site (SNS Facebook made by a group of young Cubans residents in the country, as a result of a qualitative research of an empirical-descriptive nature. The virtual ethnography is the main methodological strategy and it is complemented with the application of different techniques like the documentary and literature review, the semi-structured interview and the discussion group. As a part of the analysis’ results, are referred some of the determinant factors of the social uses of Facebook and are described the practices of the young associated with the better use of the techno-communicatives codes of the computing platform, the content production and the collective construction of meaning in this particular network environment. Among the main conclusions of the study, the relevance of the category social uses for the analysis of socio-historical and cultural processes mediated by and mediators of ICT is reaffirmed.

Ring-Resonator/Sol-Gel Interferometric Immunosensor

Science.gov (United States)

Bearman, Gregory; Cohen, David

2007-01-01

A proposed biosensing system would be based on a combination of (1) a sensing volume containing antibodies immobilized in a sol-gel matrix and (2) an optical interferometer having a ring resonator configuration. The antibodies would be specific to an antigen species that one seeks to detect. In the ring resonator of the proposed system, light would make multiple passes through the sensing volume, affording greater interaction length and, hence, greater antibody- detection sensitivity.

Development of a computer control system for the RCNP ring cyclotron

International Nuclear Information System (INIS)

Ogata, H.; Yamazaki, T.; Ando, A.; Hosono, K.; Itahashi, T.; Katayama, I.; Kibayashi, M.; Kinjo, S.; Kondo, M.; Miura, I.; Nagayama, K.; Noro, T.; Saito, T.; Shimizu, A.; Uraki, M.; Maruyama, M.; Aoki, K.; Yamada, S.; Kodaira, K.

1990-01-01

A hierarchically distributed computer control system for the RCNP ring cyclotron is being developed. The control system consists of a central computer and four subcomputers which are linked together by an Ethernet, universal device controllers which control component devices, man-machine interfaces including an operator console and interlock systems. The universal device controller is a standard single-board computer with an 8344 microcontroller and parallel interfaces, and is usually integrated into a component device and connected to a subcomputer by means of an optical-fiber cable to achieve high-speed data transfer. Control sequences for subsystems are easily produced and improved by using an interpreter language named OPELA (OPEration Language for Accelerators). The control system will be installed in March 1990. (orig.)

Cyclopeptide alkaloids. Synthesis of the ring system and its ion affinity

International Nuclear Information System (INIS)

Lagarias, J.C.; Houghten, R.A.; Rapoport, H.

1978-01-01

Several examples of the 14-membered, para-bridged ring system of the cyclopeptide alkaloids have been synthesized via an active ester cyclization. The yield of monomeric cyclopeptide varied from 1 to 33% and was affected by the amino acid substitution pattern and amide conformation of the linear peptide precursors. Both the synthetic models and a naturally occurring cyclopeptide alkaloid, ceanothine B, bind monovalent (Li + ) and divalent (Ca 2+ , Mg 2+ ) cations. 4 figures, 1 table

Overall design concepts for the APS storage ring machine protection system

International Nuclear Information System (INIS)

Lumpkin, A.; Fuja, R.; Votaw, A.; Wang, X.; Shu, D.; Stepp, J.; Arnold, N.; Nawrocki, G.; Decker, G.; Chung, Y.

1995-01-01

The basic design and status of the machine protection system for the Advanced Photon Source (APS) storage ring are discussed. The machine is passively safe to the bending magnet sources, but the high power of the insertion devices requires missteering conditions to be identified and the beam aborted in less than one millisecond. The basic aspects of waterflow, temperature, beam position, etc. monitoring are addressed. Initial commissioning of subsystems and sensors is statused

Alignment of Duke free electron laser storage ring and optical beam delivery system

International Nuclear Information System (INIS)

Emamian, M.; Hower, N.

1999-01-01

Duke Free Electron Laser Laboratory (DFELL) hosts a 1.1 GeV electron beam storage ring facility which is capable of generating beams in the range of nearly monochromatic gamma rays to high peak power infra red (IR) laser. In this report specifications and procedures for alignment of OK-4 /Duke storage ring FEL wiggler and optical cavity mirrors will be discussed. The OK-4 FEL lasing has demonstrated a series of world record in the last few years. In August of this year the OK-4 FEL successfully commissioned to laser at 193.7 nm. Also in this article, alignment of the γ-ray and UV optical beam delivery system that is currently in progress will be described. (authors)

The Beam Loss Detection System of the LHC Ring

CERN Document Server

Gschwendtner, E; Ferioli, G; Friesenbichler, W; Kain, V

2002-01-01

At the Large Hadron Collider (LHC) a beam loss system will be installed in the arc, dispersion suppressor and the straight regions for a continuous surveillance of particle losses. These beam particles deposit their energy partially in the super-conducting coils leading to temperature increase, possible magnet quenches and damages. The primary and secondary halo of the beam is absorbed by the collimation system. The tertiary halo will be lost at aperture limits in the ring. Its loss distribution along the magnets has been studies. At the positions, where most of the beam losses are expected, simulations of the particle fluences outside the cryostat and induced by lost protons at the aperture have been performed with the Monte Carlo Code Geant 3.2.1. This allows determining the most suitable positions of the detectors, the needed number of monitors and the impact on the dynamic range of the detectors. The design of the beam loss monitor system is presented that meet the required sensitivity, dynamic range and ...

An Ionosphere/Magnetosphere Coupling Current System Located in the Gap Between Saturn and its Rings

Science.gov (United States)

Khurana, K. K.; Dougherty, M. K.; Cao, H.; Hunt, G. J.; Provan, G.

2017-12-01

The Grand Finale Orbits of the Cassini spacecraft traversed through Saturn's D ring and brought the spacecraft to within 3000 km of Saturn's cloud tops. The closest approaches (CA) were near the equatorial plane of Saturn and were distributed narrowly around the local noon. The difference field (observations - internal field - magnetospheric ring current field) obtained from the Grand Finale orbits show persistent residual fields centered around the CA which diminish at higher latitudes on field lines that connect to the ring. Modeling of this perturbation in terms of internal harmonics shows that the perturbation is not of internal origin but is produced by external currents that couple the ionosphere to the magnetosphere. The sense of the current system suggests that the southern feet of the field lines in the ionosphere lead their northern footprints. We show that the observed field perturbations are consistent with a meridional Pedersen current whose strength is 1 MA/radian, i.e. comparable in strength to the Planetary-period-oscillation related current systems observed in the auroral zone. We show that the implied Lorentz force in the ionosphere extracts momentum from the faster moving southern ionosphere and passes it on to the northern ionosphere. We discuss several ideas for generating this current system. In particular, we highlight a mechanism that involves shears in the neutral winds in the thermospheric region to generate the observed magnetic field.

Coherence resonance and stochastic resonance in directionally coupled rings

Science.gov (United States)

Werner, Johannes Peter; Benner, Hartmut; Florio, Brendan James; Stemler, Thomas

2011-11-01

In coupled systems, symmetry plays an important role for the collective dynamics. We investigate the dynamical response to noise with and without weak periodic modulation for two classes of ring systems. Each ring system consists of unidirectionally coupled bistable elements but in one class, the number of elements is even while in the other class the number is odd. Consequently, the rings without forcing show at a certain coupling strength, either ordering (similar to anti-ferromagnetic chains) or auto-oscillations. Analysing the bifurcations and fixed points of the two ring classes enables us to explain the dynamical response measured to noise and weak modulation. Moreover, by analysing a simplified model, we demonstrate that the response is universal for systems having a directional component in their stochastic dynamics in phase space around the origin.

Marginal Accuracy of Castings Fabricated with Ringless Casting Investment System and Metal Ring Casting Investment System: A Comparative Study.

Science.gov (United States)

Kalavathi, M; Sachin, Bhuvana; Prasanna, B G; Shreeharsha, T V; Praveen, B; Ragher, Mallikarjuna

2016-02-01

The thermal expansion of the investment can be restricted by the metal casting ring because the thermal expansion of the ring is less than that of the investment. The ringless casting procedure is in use in clinical dentistry, though there is little scientific data to support its use in fixed partial dentures. In this study, marginal discrepancy of castings produced with the ringless casting technique and the conventional technique using the metal rings were compared. A total of 30 wax patterns were fabricated directly on a metal die. Optical stereomicroscope was used to measure the marginal discrepancy between the metal die and wax patterns. A total of 15 castings were invested using Bellavest T phosphate-bonded investment with the ringless technique and 15 were invested with the same investment with a metal ring; 30 castings were produced using a nickel-chromium ceramo-metal alloy. The internal surface of the castings was not modified and seated with finger pressure. The vertical marginal discrepancy was measured using an optical stereomicroscope at a magnification of 100x. The data obtained were statistically analyzed using students t-test (paired t-test and unpaired t-test). The castings of the ringless technique provided less vertical marginal discrepancy (240.56 ± 45.81 μ) than the castings produced with the conventional metal ring technique (281.98± 53.05 μ). The difference was statistically significant. The ringless casting technique had produced better marginal accuracy compared with conventional casting technique. Ringless casting system can be used routinely for clinical purpose.

Moving ring reactor 'Karin-1'

International Nuclear Information System (INIS)

1983-12-01

The conceptual design of a moving ring reactor ''Karin-1'' has been carried out to advance fusion system design, to clarify the research and development problems, and to decide their priority. In order to attain these objectives, a D-T reactor with tritium breeding blanket is designed, a commercial reactor with net power output of 500 MWe is designed, the compatibility of plasma physics with fusion engineering is demonstrated, and some other guideline is indicated. A moving ring reactor is composed mainly of three parts. In the first formation section, a plasma ring is formed and heated up to ignition temperature. The plasma ring of compact torus is transported from the formation section through the next burning section to generate fusion power. Then the plasma ring moves into the last recovery section, and the energy and particles of the plasma ring are recovered. The outline of a moving ring reactor ''Karin-1'' is described. As a candidate material for the first wall, SiC was adopted to reduce the MHD effect and to minimize the interaction with neutrons and charged particles. The thin metal lining was applied to the SiC surface to solve the problem of the compatibility with lithium blanket. Plasma physics, the engineering aspect and the items of research and development are described. (Kako, I.)

High resolution upgrade of the ATF damping ring BPM system

International Nuclear Information System (INIS)

Terunuma, N.; Urakawa, J.; Frisch, J.; May, J.; McCormick, D.; Nelson, J.; Seryi, A.; Smith, T.; Woodley, M.; Briegel, C.; Dysert, R.

2008-01-01

A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring has been accomplished in its first stage, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R and D effort. The upgrade consists of a high resolution, high reproducibility read-out system, based on analog and digital downconversion techniques, digital signal processing, and also tests a new automatic gain error correction schema. The technical concept and realization, as well as preliminary results of beam studies are presented

Digital Low Level RF Systems for Fermilab Main Ring and Tevatron

Science.gov (United States)

Chase, B.; Barnes, B.; Meisner, K.

1997-05-01

At Fermilab, a new Low Level RF system is successfully installed and operating in the Main Ring. Installation is proceeding for a Tevatron system. This upgrade replaces aging CAMAC/NIM components for an increase in accuracy, reliability, and flexibility. These VXI systems are based on a custom three channel direct digital synthesizer(DDS) module. Each synthesizer channel is capable of independent or ganged operation for both frequency and phase modulation. New frequency and phase values are computed at a 100kHz rate on the module's Analog Devices ADSP21062 (SHARC) digital signal processor. The DSP concurrently handles feedforward, feedback, and beam manipulations. Higher level state machines and the control system interface are handled at the crate level using the VxWorks operating system. This paper discusses the hardware, software and operational aspects of these LLRF systems.

Flux qubits on semiconducting quantum ring

International Nuclear Information System (INIS)

Szopa, M; Zipper, E

2010-01-01

The ability to control the quantum state of a single electrons in a quantum ring made of a semiconductor is at the heart of recent developments towards a scalable quantum computer. A peculiar dispersion relation of quantum rings allows to steer the ground state properties by the magnetic flux and offers spin and orbital degrees of freedom for quantum manipulations. We show that such ring can be effectively reduced to the two-state system forming a qubit on orbital or spin degrees of freedom.

An active feedback system to control synchrotron oscillations in the SLC Damping Rings

International Nuclear Information System (INIS)

Corredoura, P.L.; Pellegrin, J.L.; Schwarz, H.D.; Sheppard, J.C.

1989-03-01

Initially the SLC Damping Rings accomplished Robinson instability damping by operating the RF accelerating cavities slightly detuned. In order to be able to run the cavities tuned and achieve damping for Robinson instability and synchrotron oscillations at injection an active feedback system has been developed. This paper describes the theoretical basis for the feedback system and the development of the hardware. Extensive measurements of the loop response including stored beam were performed. Overall performance of the system is also reported. 3 refs., 6 figs

Black rings

International Nuclear Information System (INIS)

Emparan, Roberto; Reall, Harvey S

2006-01-01

A black ring is a five-dimensional black hole with an event horizon of topology S 1 x S 2 . We provide an introduction to the description of black rings in general relativity and string theory. Novel aspects of the presentation include a new approach to constructing black ring coordinates and a critical review of black ring microscopics. (topical review)

Beam Profile Measurement with Flying Wires at the Fermilab Recycler Ring

CERN Document Server

Hu, Martin; Krider, John; Lorman, Eugene; Marchionni, Alberto; Pishchalnikov, Yu M; Pordes, Stephen; Slimmer, David; Wilson, Peter R; Zagel, James

2005-01-01

The Fermilab Recycler Ring is a high vacuum fixed energy antiproton storage ring with stochastic and electron cooling systems. Flying wires were installed at the Fermilab Recycler Ring for transverse beam profile measurement. The following note describes the system configuration, calibration and resolution of the flying wire system, as well as analysis of the transverse beam profile in the presence of both cooling systems.

Helicobacter pylori cagA and vacA genotypes in Cuban and Venezuelan populations

Directory of Open Access Journals (Sweden)

Diana Ortiz-Princz

2010-05-01

Full Text Available The aim of this study was to determine the presence of Helicobacter pylori cytotoxin-associated gene (cagA/vacuolating cytotoxin gene (vacA among patients with chronic gastritis in Cuba and Venezuela. Gastric antrum biopsies were taken for culture, DNA extraction and PCR analysis. Amplification of vacA and cagA segments was performed using two regions of cagA: 349 bp were amplified with the F1/B1 primers and the remaining 335 bp were amplified with the B7629/B7628 primers. The VA1-F/VA1-R set of primers was used to amplify the 259-bp (s1 or 286-bp (s2 product and the VAG-R/VAG-F set of primers was used to amplify the 567-bp (m1 or 642-bp (m2 regions of vacA. cagA was detected in 87% of the antral samples from Cuban patients and 80.3% of those from Venezuelan patients. All possible combinations of vacA regions were found, with the exception of s2/m1. The predominant combination found in both countries was s1/m1. The percentage of cagA+ strains was increased by the use of a second set of primers and a greater number of strains was amplified with the B7629/B7628 primers in the Cuban patients (p = 0.0001. There was no significant difference between the presence of the allelic variants of vacA and cagA in both populations. The predominant genotype was cagA+/s1m1 in both countries. The results support the necessary investigation of isolates circulating among the human population in each region.

LOCATING THE TRAILING EDGE OF THE CIRCUMBINARY RING IN THE KH 15D SYSTEM

International Nuclear Information System (INIS)

Capelo, Holly L.; Herbst, William; Leggett, S. K.; Hamilton, Catrina M.; Johnson, John A.

2012-01-01

Following two years of complete occultation of both stars in the binary T Tauri star KH 15D by its opaque circumbinary ring, KH 15D has abruptly brightened again during apastron phases, reaching I = 15 mag. Here, we show that the brightening is accompanied by a change in spectral class from K6/K7 (the spectral class of star A) to ∼K1, and a bluing of the system in V – I by about 0.3 mag. A radial velocity measurement confirms that, at apastron, we are now seeing direct light from star B, which is more luminous and of earlier spectral class than star A. Evidently, the trailing edge of the occulting screen has just become tangent to one anse of star B's projected orbit. This confirms a prediction of the precession models, supports the view that the tilted ring is self-gravitating, and ushers in a new era of the system's evolution that should be accompanied by the same kind of dramatic phenomena observed from 1995 to 2009. It also promotes KH 15D from a single-lined to a double-lined eclipsing binary, greatly enhancing its value for testing pre-main-sequence models. The results of our study strengthen the case for truncation of the outer ring at around 4 AU by a sub-stellar object such as an extremely young giant planet. The system is currently at an optimal configuration for detecting the putative planet and we urge expedient follow-up observations.

Composite correlation filter for O-ring detection in stationary colored noise

Science.gov (United States)

Hassebrook, Laurence G.

2009-04-01

O-rings are regularly replaced in aircraft and if they are not replaced or if they are installed improperly, they can result in catastrophic failure of the aircraft. It is critical that the o-rings be packaged correctly to avoid mistakes made by technicians during routine maintenance. For this reason, fines may be imposed on the o-ring manufacturer if the o-rings are packaged incorrectly. That is, a single o-ring must be packaged and labeled properly. No o-rings or more than one o-ring per package is not acceptable. We present an industrial inspection system based on real-time composite correlation filtering that has successfully solved this problem in spite of opaque paper o-ring packages. We present the system design including the composite filter design.

Efficient Test Application for Core-Based Systems Using Twisted-Ring Counters

OpenAIRE

Anshuman Chandra; Krishnendu Chakrabarty; Mark C. Hansen

2001-01-01

We present novel test set encoding and pattern decompression methods for core-based systems. These are based on the use of twisted-ring counters and offer a number of important advantages–significant test compression (over 10X in many cases), less tester memory and reduced testing time, the ability to use a slow tester without compromising test quality or testing time, and no performance degradation for the core under test. Surprisingly, the encoded test sets obtained from partially-specified...

Mechanical loading of the gymnast’s motor system during swings on rings

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R Serafin

2008-12-01

Full Text Available The aim of this work was to identify the mechanical loading of the gymnast’s motor system during forward and backward swings on gymnastic rings. A junior gymnast of the First Class, aged 14, with body mass 53.1 kg and body length 1.61 m, participated in the study. He executed a series of ten cyclic swing movements on rings with his maximum amplitude. Kinematic variables of the gymnast’s centre of mass (COM as well as reaction forces in the cables were measured and synchronized using the SIMI MOTION movement analysis system. Two separate phases of mechanical loading of the motor system have been identified: resistance phase and non resistance phase. In the non resistance phase the gymnast attains similar values of the COM’s momentum but different angular displacements. In the resistance phase the forces acting on the motor system have their maximum. They amount to 5.5 BW for the forward swing and 6.5 BW for the backward swing movement. The maximum rate of change of the force for forward and backward swing is 42.6 BWs-1 and 67.4 BWs-1, respectively. These two variables differentiate the mechanical loading of the gymnast’s motor system between forward and backward swings. The reaction force produced by the gymnast is significantly greater during the execution of forward swings. It seems probable that horizontal displacements of COM may be the factor responsible for reduction of the mechanical loading experienced by the gymnast.

Cuban experience in dosimetry quality audit program in radiotherapy

International Nuclear Information System (INIS)

Alonso-Samper, J.L.; Dominguez, L.; Yip, F.G.; Laguardia, R.A.; Morales, J.L.; Larrinaga, E.

2002-01-01

Full text: Five years ago we started a National Program of Quality Assurance in Radiotherapy. This program was possible thanks to the cooperation between the Cuban Ministry of Health and the International Atomic Energy Agency (IAEA) in the Projects ARCAL XXX and CUB/6/011. In the framework of these projects a total of ten complete dosimetry set were acquired and a large number of medical physicists were trained. At the same time, the Cuban side signed a contract for nine cobalt units, which have been gradually installed and all of them are running at the moment. During more than 20 years Cuba has taken part in the IAEA/WHO TLD postal dose audit programs and our results have been inside the (+/-)5 % acceptance limit. Cuba also joined the IAEA Coordinated Research Program E2 40 07, to extend at a national level the experience of the TLD based audits, using the capability of our SSDL to measure TLD. At the same time the work of the already existing External Audit Group was consolidated. The National Program of Quality Assurance in Radiotherapy works on base of external on-site visits. The main objective is to avoid any accident and to improve the quality of the RT treatments. Every year each Radiotherapy service is visited by a qualified team of physicists with the objective to check the physical aspects of the quality of the RT treatment, it includes: Documents and Records, safety, mechanical and dosimetric aspects, treatment planning, also we use the fixed depth phantom to simulate and verify several techniques. Although the TLD postal audit results are acceptable, in our QA audits we have detected some problems that may deviate the dose delivery to patients in more than 5%, examples of which are: Not all the clinical plans are redundantly checked by an independent person; Not all the controls (daily, monthly and annual) are performed according to the protocols approved by the National QA Committee. In some cases the controls are not well recorded; Clinical

Variations in Ring Particle Cooling across Saturn's Rings with Cassini CIRS

Science.gov (United States)

Brooks, S. M.; Spilker, L. J.; Pilorz, S.; Edgington, S. G.; Déau, E.; Altobelli, N.

2010-12-01

Cassini's Composite Infrared Spectrometer has recorded over two million of spectra of Saturn's rings in the far infrared since arriving at Saturn in 2004. CIRS records far infrared radiation between 10 and 600 cm-1 ( 16.7 and 1000 μ {m} ) at focal plane 1 (FP1), which has a field of view of 3.9 mrad. Thermal emission from Saturn’s rings peaks in this wavelength range. Ring temperatures can be inferred from FP1 data. By tracking how ring temperatures vary, we can determine the thermal inertia of the rings. Previous studies have shown that the rings' thermal inertia, a measure of their response to changes in the thermal environment, varies from ring to ring. Thermal inertia can provide insight into the physical structure of Saturn's ring particles and their regoliths. Low thermal inertia and rapidly changing temperatures are suggestive of ring particles that have more porous or fluffy regoliths or that are riddled with cracks. Solid particles can be expected to have higher thermal inertias. Ferrari et al. (2005) fit thermal inertia values of 5218 {Jm)-2 {K}-1 {s}-1/2 to their B ring data and 6412 {Jm)-2 {K}-1 {s}-1/2 to their C ring data. In this work we focus on CIRS observations of the shadowed portion of Saturn's rings. The rings’ thermal budget is dominated by its absorption of solar radiation. As a result, ring particles abruptly cool as they traverse Saturn's shadow. From these shadow observations we can create cooling curves at specific locations across the rings. We will show that the rings' cooling curves and thus their thermal inertia vary not only from ring to ring, but by location within the individual rings. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Copyright 2010 California Institute of Technology. Government sponsorship acknowledged.

Seco-B-Ring Steroidal Dienynes with Aromatic D Ring: Design, Synthesis and Biological Evaluation

Directory of Open Access Journals (Sweden)

Marcin Szybinski

2017-10-01

Full Text Available Continuing our structure-activity studies on the vitamin D analogs with the altered intercyclic seco-B-ring fragment, we designed compounds possessing dienyne system conjugated with the benzene D ring. Analysis of the literature data and the docking experiments seemed to indicate that the target compounds could mimic the ligands with a good affinity to the vitamin D receptor (VDR. Multi-step synthesis of the C/D-ring building block of the tetralone structure was achieved and its enol triflate was coupled with the known A-ring fragments, possessing conjugated enyne moiety, using Sonogashira protocol. The structures of the final products were confirmed by NMR, UV and mass spectroscopy. Their binding affinities for the full-length human VDR were determined and it was established that compound substituted at C-2 with exomethylene group showed significant binding to the receptor. This analog was also able to induce monocytic differentiation of HL-60 cells.

Structural and magnetic characterization of a tetranuclear copper(II) cubane stabilized by intramolecular metal cation-π interactions.

Science.gov (United States)

Papadakis, Raffaello; Rivière, Eric; Giorgi, Michel; Jamet, Hélène; Rousselot-Pailley, Pierre; Réglier, Marius; Simaan, A Jalila; Tron, Thierry

2013-05-20

A novel tetranuclear copper(II) complex (1) was synthesized from the self-assembly of copper(II) perchlorate and the ligand N-benzyl-1-(2-pyridyl)methaneimine (L(1)). Single-crystal X-ray diffraction studies revealed that complex 1 consists of a Cu4(OH)4 cubane core, where the four copper(II) centers are linked by μ3-hydroxo bridges. Each copper(II) ion is in a distorted square-pyramidal geometry. X-ray analysis also evidenced an unusual metal cation-π interaction between the copper ions and phenyl substituents of the ligand. Calculations based on the density functional theory method were used to quantify the strength of this metal-π interaction, which appears as an important stabilizing parameter of the cubane core, possibly acting as a driving parameter in the self-aggregation process. In contrast, using the ligand N-phenethyl-1-(2-pyridyl)methaneimine (L(2)), which only differs from L(1) by one methylene group, the same synthetic procedure led to a binuclear bis(μ-hydroxo)copper(II) complex (2) displaying intermolecular π-π interactions or, by a slight variation of the experimental conditions, to a mononuclear complex (3). These complexes were studied by X-ray diffraction techniques. The magnetic properties of complexes 1 and 2 are reported and discussed.

3d-4f {Co(II)3Ln(OR)4} Cubanes as Bio-Inspired Water Oxidation Catalysts.

Science.gov (United States)

Evangelisti, Fabio; Moré, René; Hodel, Florian; Luber, Sandra; Patzke, Greta Ricarda

2015-09-02

Although the {CaMn4O5} oxygen evolving complex (OEC) of photosystem II is a major paradigm for water oxidation catalyst (WOC) development, the comprehensive translation of its key features into active molecular WOCs remains challenging. The [Co(II)3Ln(hmp)4(OAc)5H2O] ({Co(II)3Ln(OR)4}; Ln = Ho-Yb, hmp = 2-(hydroxymethyl)pyridine) cubane WOC series is introduced as a new springboard to address crucial design parameters, ranging from nuclearity and redox-inactive promoters to operational stability and ligand exchange properties. The {Co(II)3Ln(OR)4} cubanes promote bioinspired WOC design by newly combining Ln(3+) centers as redox-inactive Ca(2+) analogues with flexible aqua-/acetate ligands into active and stable WOCs (max. TON/TOF values of 211/9 s(-1)). Furthermore, they open up the important family of 3d-4f complexes for photocatalytic applications. The stability of the {Co(II)3Ln(OR)4} WOCs under photocatalytic conditions is demonstrated with a comprehensive analytical strategy including trace metal analyses and solution-based X-ray absorption spectroscopy (XAS) investigations. The productive influence of the Ln(3+) centers is linked to favorable ligand mobility, and the experimental trends are substantiated with Born-Oppenheimer molecular dynamics studies.

Hall-effect electric fields in semiconducting rings. II

International Nuclear Information System (INIS)

Gorodzha, L.V.; Emets, Yu.P.; Stril'ko, S.I.

1987-01-01

A calculation is presented for the current density distribution in a semiconducting ring with two electrodes symmetrically located on the outer boundary (system II, Fig. 1). The difference between this electrode position and that on the ring considered previously (system I) leads to substantial changes in the shape of the electric field

Domino Wittig Diels-Alder reaction: An expeditious entry into the AB ring system of furanosesquiterpenes

Digital Repository Service at National Institute of Oceanography (India)

Patre, R.E.; Gawas, S.; Sen, S.; Parameswaran, P.S.; Tilve, S.G.

A domino Wittig Diels - Alder reaction has been employed in delineating a short and flexible synthetic stratagem for ready access to the AB ring system and the tricyclic framework of furanosesquiterpenes, such as the bioactive natural products...

Effects of Cuban Crude Oil on the Process of Leach, Sedimentation and Distillation in Nicaro

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Ing. María Elena Magaña-Haynes

2015-11-01

Full Text Available ine"> Cuban crude in the process of leaching, sedimentation and distillation ofthe processed minerals at “René Ramos Latour” Company was evaluated. Two periods of testswere performed; one when oil was introduced into the furnace by spear and the other when itwas introduced by spear and chamber. The results demonstrated the feasibility of using theCuban crude in reduction and leaching process of mineral by the use of spear and chamber aswell. Nickel and cobalt extractions achieved by stepwise exceed values found in the relatedliterature. Deposition of mineral was good reaching values of 1,736 -1,745 kg/m3 at the bottomof the sedimentation stage leach and 1,774 -1,807 kg/m3 in the washing stage. The thickenerswere maintained with high clear liquor level throughout the test with values between 28,0-30,0ppm. The sedimentation rate achieved low values both in the first and in the second leachingstage. Sedimentation unit area was 0,23 m2 /T day, so that no sedimentation problems werepresented. It was observed an increase in the sulfur content up to values of 6,52 g/L for a nickelcontent of 12,0g/L, which caused that the dissolved nickel in downloading stills were of 0,392 g/L and 2,58 g/L of ammonia. The sulfur content in the nickel carbonate was increased upto 6,30 %, which is 2,5 % higher than conventional.

Scaling cigars in the Cuban tourism economy Configurar a escala dos charutos na economia do turismo em Cuba

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Valerio Simoni

2009-11-01

Full Text Available Taking scale as an object of analysis (Tsing 2000, this article examines how competing scale-making projects emerge in different layers of the Cuban tourism economy. I consider how tourists and Cubans interact along contested chains of production and distribution of cigars, and therefore become entangled in bundles of ideas, discourses, practices and materialities. These constitute different scaling propositions on which tourists and Cubans converge or diverge, and which inform the success of encounters within the tourism economy. Highlighted is the importance of understanding how scaling propositions are enacted and negotiated within tourism. I conclude that the realm of tourism is a particularly fruitful platform to investigate how competing scale-making projects and notions of scale are played out in the contemporary world.Tomando a escala (Tsing 2000 como objecto de análise, este artigo aborda a forma como emergem projectos concorrentes de configuração de escala a diferentes níveis da economia turística cubana. É examinada a interacção de turistas e cubanos no âmbito de cadeias de produção e distribuição controversas, e as formas como, assim, uns e outros se envolvem em conjuntos de ideias, discursos, práticas e materialidades. Estes constituem diferentes propostas de configuração de escala em que turistas e cubanos convergem ou divergem e que determinam o sucesso dos encontros no seio da economia turística. É aqui sublinhada a importância de compreendermos como as propostas de configuração de escala são apresentadas e negociadas no âmbito do turismo. Conclui-se que o campo do turismo constitui uma plataforma particularmente fértil para o estudo de como noções de escala e projectos de configuração de escala concorrentes se desenvolvem no mundo contemporâneo.

Modificaciones en las calderas igneotubulares cubanas // Modifications in the Cuban boilers of fire tube

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I. Pérez Mallea

1998-01-01

Full Text Available El objetivo de este trabajo es optimizar y diseñar las calderas igneotubulares nacionales, incluyendo las de inversión de llama yagua caliente. Con este fin se creo un software como soporte científico técnico que permite realizar los diferentes cálculosverificativos a través de los cuales se optimiza._________________________________________________________________________Abstract .The objective of this work is the optimizing and designing of the Cuban boilers of fire tube, including those of inverting offlame and hot water. A software have been developed as technical scientific supper for different calculations and optimizingprocess.

Comparison of disposable sutureless silicone ring and traditional metal ring in 23-gauge vitrectomy combined with cataract surgery.

Science.gov (United States)

Wu, Jian-Guo; Wei, Rui-Hua; Liu, Ai-Hua; Zhou, Xiao-Xu; Sun, Guo-Ling; Li, Xiao-Rong

2011-01-01

The purpose of this prospective, interventional, comparative case series was to evaluate the efficiency and feasibility of a disposable sutureless silicone lens ring for corneal contact lens stabilization during combined 23-gauge vitrectomy and cataract surgery. We developed a ring consisting of a single silicone component with three footplates along the ring margin to fit cannulae for holding conventional contact lenses. Thirty eyes from 30 patients with cataract and vitreoretinal disease were included, and divided into two matched groups according to disease type and ring used. In Group A, we used a 23-gauge transconjunctival vitrectomy system and a disposable sutureless silicone lens ring (n = 15). In Group B, we used a 23-gauge transconjunctival vitrectomy system and a conventional metal lens ring (n = 15). The main outcome measures were: time required for vitrectomy preparation, rate of intraoperative corneal limbus bleeding, and limbus scar rate at the final follow-up visit. Thirty cases were successfully completed. The average vitrectomy preparation time was less in Group A than in Group B (P < 0.01), and the average preparation time saved was 3.94 minutes. None of the Group A patients had intraoperative bleeding or postoperative scarring, whereas all 15 Group B cases had bleeding and five had scarring. There was a statistically significant difference between Group A and Group B for these complications (P ≤ 0.05). This report demonstrates the advantages of using a sutureless silicone ring during combined 23-gauge vitrectomy and cataract surgery. Using this method could allow extra time for the surgeon to pay more attention to complex vitreoretinal procedures.

Alternative loop rings

CERN Document Server

Goodaire, EG; Polcino Milies, C

1996-01-01

For the past ten years, alternative loop rings have intrigued mathematicians from a wide cross-section of modern algebra. As a consequence, the theory of alternative loop rings has grown tremendously. One of the main developments is the complete characterization of loops which have an alternative but not associative, loop ring. Furthermore, there is a very close relationship between the algebraic structures of loop rings and of group rings over 2-groups. Another major topic of research is the study of the unit loop of the integral loop ring. Here the interaction between loop rings and group ri

Primitivity and weak distributivity in near rings and matrix near rings

International Nuclear Information System (INIS)

Abbasi, S.J.

1993-08-01

This paper shows the structure of matrix near ring constructed over a weakly distributive and primative near ring. It is proved that a weakly distributive primitive near ring is a ring and the matrix near rings constructed over it is also a bag. (author). 14 refs

Dynamical black rings with a positive cosmological constant

International Nuclear Information System (INIS)

Kimura, Masashi

2009-01-01

We construct dynamical black ring solutions in the five-dimensional Einstein-Maxwell system with a positive cosmological constant and investigate the geometrical structure. The solutions describe the physical process such that a thin black ring at early time shrinks and changes into a single black hole as time increases. We also discuss the multiblack rings and the coalescence of them.

Analysis of controversial items in the theoretical design of the undergraduate's thesis at the Cuban University of Informatics Sciences (UIS.

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Rolando Quintana Aput

2011-03-01

Full Text Available The present paper encloses the analysis of some troubles related to the development of theoretical design concerning the undergraduate thesis at the Cuban University of Informatics Sciences (UIS. This analysis proves to be decisive due to the existing demand for improving professionals training in the fields of investigation related to computing world.

Further explorations of cosmogonic shadow effects in the Saturnian rings

International Nuclear Information System (INIS)

Alfven, H.; Axnaes, I.; Brenning, N.; Lindqvist, P.A.

1985-01-01

The mass distribution in the Saturnian ring system is investigated and compared with predictions from the cosmogonic theory by Alfven and Arrhenius. According to this theory, the matter in the rings has once been in the form of a magnetized plasma, in which the gravitation is balanced partly by the centrifugal force and partly by the magnetic field. As the plasma is neutralized, the magnetic force disappears and the matter can be shown to fall in to a distance 2/3 of the original. This gives cause to the so called 'cosmogonic shadow effect', which has been demonstrated earlier for the astroidal belt and in the large scale structure of the Saturnian ring system. The relevance of the cosmogonic shadow effect is investigated for parts of the finer structures of the Saturnian ring system. It is shown that many structures of the present ring system can be understood as shadows and antishadows of cosmogonic origin. These appear in the form of double rings centered around a position a factor 0.64 (slightly less than 2/3) closer to Saturn than the causing feature. (author)

Internal Dosimetry and the pharmacokinetic of the Cuban Kit of Methoxy-Isobutyl-Isonitrile (MIBI) marked with 99mTc

International Nuclear Information System (INIS)

Torres, L.A.; Pereztol, O.; Rodriguez, J.L.; Alvarez, I.; Fraxedas, R.; Mesa, G.; Rodriguez, R.

1998-01-01

The objective of the present work consisted on evaluating the Internal Dosimetry and the pharmacokinetic of the Cuban Kit of Methoxy-Isobutyl-Isonitrile (MIBI) marked with 99mTc. In the dosimetry studies and biodistribution five healthy volunteers were included and in the pharmacokinetic studies five patients were included with less than 5% of probability of suffering illness of artery coronary

An antecedent of the new teacher’s training school: an approach to a behavioral model and a school model from the perspective of the history of Cuban education

Directory of Open Access Journals (Sweden)

González, E. A.

2011-07-01

Full Text Available The paper is intended to portray the most important qualities and attitudes that distinguish the model of a teacher’s training school, a project for educating would-be teachers for Kindergarten, Primary School and Special Education. The idea that Cuban Pedagogy is a natural source of ideas for sustaining such model as well as characterizing social agents’ attitudes and the institution’s features is argued. A logical-historic analysis is carried out, starting by considering some of the most important Cuban school teachers’ criteria, from which the author infers the qualities and ethical attitudes that characterize the social participants and the whole institution.

Comparison of disposable sutureless silicone ring and traditional metal ring in 23-gauge vitrectomy combined with cataract surgery

Directory of Open Access Journals (Sweden)

Li X-R

2011-06-01

Full Text Available Jian-Guo Wu, Rui-Hua Wei, Ai-Hua Liu, Xiao-Xu Zhou, Guo-Ling Sun, Xiao-Rong LiTianjin Medical University Eye Center, Tianjin, ChinaBackground: The purpose of this prospective, interventional, comparative case series was to evaluate the efficiency and feasibility of a disposable sutureless silicone lens ring for corneal contact lens stabilization during combined 23-gauge vitrectomy and cataract surgery.Methods: We developed a ring consisting of a single silicone component with three footplates along the ring margin to fit cannulae for holding conventional contact lenses. Thirty eyes from 30 patients with cataract and vitreoretinal disease were included, and divided into two matched groups according to disease type and ring used. In Group A, we used a 23-gauge transconjunctival vitrectomy system and a disposable sutureless silicone lens ring (n = 15. In Group B, we used a 23-gauge transconjunctival vitrectomy system and a conventional metal lens ring (n = 15. The main outcome measures were: time required for vitrectomy preparation, rate of intraoperative corneal limbus bleeding, and limbus scar rate at the final follow-up visit.Results: Thirty cases were successfully completed. The average vitrectomy preparation time was less in Group A than in Group B (P < 0.01, and the average preparation time saved was 3.94 minutes. None of the Group A patients had intraoperative bleeding or postoperative scarring, whereas all 15 Group B cases had bleeding and five had scarring. There was a statistically significant difference between Group A and Group B for these complications (P ≤ 0.05.Conclusion: This report demonstrates the advantages of using a sutureless silicone ring during combined 23-gauge vitrectomy and cataract surgery. Using this method could allow extra time for the surgeon to pay more attention to complex vitreoretinal procedures.Keywords: pars plana vitrectomy, contact lens, silicone ring, cataract surgery

Identification of protein binding in pictorial art Cuban

International Nuclear Information System (INIS)

Mendoza, Ariadna; Correa, Maurin; Maqueira, Isis

2011-01-01

In this paper were implemented microanalysis methodologies by histochemical analysis, and infrared spectroscopy to determine the nature of the binder in paintings and Gas Chromatography (GC) coupled to Mass Spectrometry (MS) for identification of protein binders of common use in tempera technique with the aim of having these methods as part of the identification of artistic materials in Cuban cultural heritage carried out by Archaeometry Laboratory of Havana city's Historian Cabinet. The methodologies implemented were evaluated using model samples of traditional painting techniques with variable protein binder: yolk, egg white, casein, nut oil and animal glue; ageing for 5 years. The models samples were correctly identified. It was determined the interference of pigments with the presence of nitrogen by histochemical analysis with Amido Black dye. IR spectroscopy technique allowed to differentiate between oily and mixed (oil plus protein) techniques and tempera with yolk. Oily technique was identified in wall paintings of the New San Francisco church (XIX century) and the Obrapia House (XVII century) and the technique of tempera with animal glue in the polychrome of the XVIII century which represents St. John the Evangelist belonging to the San Juan de Letran church

Klystron 'efficiency loop' for the ALS storage ring RF system

International Nuclear Information System (INIS)

Kwiatkowski, Slawomir; Julian, Jim; Baptiste, Kenneth

2002-01-01

The recent energy crisis in California has led us to investigate the high power RF systems at the Advanced Light Source (ALS) in order to decrease the energy consumption and power costs. We found the Storage Ring Klystron Power Amplifier system operating as designed but with significant power waste. A simple proportional-integrator (PI) analog loop, which controls the klystron collector beam current, as a function of the output RF power, has been designed and installed. The design considerations, besides efficiency improvement, were to interface to the existing system without major expense. They were to also avoid the klystron cathode power supply filter's resonance in the loop's dynamics, and prevent a conflict with the existing Cavity RF Amplitude Loop dynamics. This efficiency loop will allow us to save up to 700 MW-hours of electrical energy per year and increase the lifetime of the klystron

Interaction of ring dark solitons with ring impurities in Bose-Einstein condensates

International Nuclear Information System (INIS)

Xue Jukui

2005-01-01

The interaction of ring dark solitons/vortexes with the ring-shaped repulsive and attractive impurities in two-dimensional Bose-Einstein condensates is investigated numerically. Very rich interaction phenomena are obtained, i.e., not only the interaction between the ring soliton and the impurity, but also the interaction between vortexes and the impurity. The interaction characters, i.e., snaking of ring soliton, quasitrapping or reflection of ring soliton and vortexes by the impurity, strongly depend on initial ring soliton velocity, impurity strength, initial position of ring soliton and impurity. The numerical results also reveal that ring dark solitons/vortexes can be trapped and dragged by an adiabatically moving attractive ring impurity

Alstom Francis Turbine Ring Gates: from Retrofitting to Commissioning

Science.gov (United States)

A, Nguyen P.; G, Labrecque; M-O, Thibault; M, Bergeron; A, Steinhilber; D, Havard

2014-03-01

The Ring Gate synchronisation system developed by Alstom is new and patented. It uses hydraulic cylinders connected in pairs by a serial connection. The new hydraulic synchronisation system, when compared to the previous mechanical synchronisation system, has several advantages. It is a compact design; it reduces the number of mechanical components as well as maintenance costs. The new system maintains the Ring Gates robustness. The new approach is an evolution from mechanical to hydraulic synchronization assisted by electronic control. The new synchronization system eliminates several mechanical components that used to add wear and friction and which are usually difficult to adjust during maintenance. Tension chains and sprockets and associated controls are eliminated. Through the position sensors, the redundancy of the ring gate synchronization system makes it predictable and reliable. The electronic control compensates for any variation in operation, for example a leak in the hydraulic system. An emergency closing is possible without the electronic control system due to the stiffness of hydraulic serial connection in the hydraulic cylinder pairs. The Ring Gate can work safely against uneven loads and frictions. The development will be reviewed and its application discussed through commissioning results.

Alstom Francis Turbine Ring Gates: from Retrofitting to Commissioning

International Nuclear Information System (INIS)

Nguyen P A; Labrecque G; Thibault M-O; Bergeron M; Steinhilber A; Havard D

2014-01-01

The Ring Gate synchronisation system developed by Alstom is new and patented. It uses hydraulic cylinders connected in pairs by a serial connection. The new hydraulic synchronisation system, when compared to the previous mechanical synchronisation system, has several advantages. It is a compact design; it reduces the number of mechanical components as well as maintenance costs. The new system maintains the Ring Gates robustness. The new approach is an evolution from mechanical to hydraulic synchronization assisted by electronic control. The new synchronization system eliminates several mechanical components that used to add wear and friction and which are usually difficult to adjust during maintenance. Tension chains and sprockets and associated controls are eliminated. Through the position sensors, the redundancy of the ring gate synchronization system makes it predictable and reliable. The electronic control compensates for any variation in operation, for example a leak in the hydraulic system. An emergency closing is possible without the electronic control system due to the stiffness of hydraulic serial connection in the hydraulic cylinder pairs. The Ring Gate can work safely against uneven loads and frictions. The development will be reviewed and its application discussed through commissioning results

Design of the Injection and extraction system and related machine protection for the Clic Damping Rings

CERN Document Server

Apsimon, Robert; Barnes, Mike; Borburgh, Jan; Goddard, Brennan; Papaphilippou, Yannis; Uythoven, Jan

2014-01-01

Linear machines such as CLIC have relatively low rates of collision between bunches compared to their circular counterparts. In order to achieve the required luminosity, a very small spot size is envisaged at the interaction point, thus a low emittance beam is needed. Damping rings are essential for producing the low emittances needed for the CLIC main beam. It is crucial that the beams are injected and extracted from the damping rings in a stable and repeatable fashion to minimise emittance blow-up and beam jitter at the interaction point; both of these effects will deteriorate the luminosity at the interaction point. In this paper, the parameters and constraints of the injection and extraction systems are considered and the design of these systems is optimised within this parameter space. Related machine protection is considered in order to prevent damage from potential failure modes of the injection and extraction systems.

Electronic properties of superlattices on quantum rings.

Science.gov (United States)

da Costa, D R; Chaves, A; Ferreira, W P; Farias, G A; Ferreira, R

2017-04-26

We present a theoretical study of the one-electron states of a semiconductor-made quantum ring (QR) containing a series of piecewise-constant wells and barriers distributed along the ring circumference. The single quantum well and the superlattice cases are considered in detail. We also investigate how such confining potentials affect the Aharonov-Bohm like oscillations of the energy spectrum and current in the presence of a magnetic field. The model is simple enough so as to allow obtaining various analytical or quasi-analytical results. We show that the well-in-a-ring structure presents enhanced localization features, as well as specific geometrical resonances in its above-barrier spectrum. We stress that the superlattice-in-a-ring structure allows giving a physical meaning to the often used but usually artificial Born-von-Karman periodic conditions, and discuss in detail the formation of energy minibands and minigaps for the circumferential motion, as well as several properties of the superlattice eigenstates in the presence of the magnetic field. We obtain that the Aharonov-Bohm oscillations of below-barrier miniband states are reinforced, owing to the important tunnel coupling between neighbour wells of the superlattice, which permits the electron to move in the ring. Additionally, we analysis a superlattice-like structure made of a regular distribution of ionized impurities placed around the QR, a system that may implement the superlattice in a ring idea. Finally, we consider several random disorder models, in order to study roughness disorder and to tackle the robustness of some results against deviations from the ideally nanostructured ring system.

Simulation of a transverse feedback system for the SSRF storage ring

International Nuclear Information System (INIS)

Jiang Bocheng; Chinese Academy of Sciences, Beijing; Liu Guimin; Zhao Zhentang

2007-01-01

Resistive wall instability is a serious problem in many light sources. An active transverse feedback system (TFS) is required to operate the machine in a good condition when beam current is high. In order to investigate beam dynamics with TFS turned on, we developed a TFS simulation program. The feedback effectiveness for the Shanghai Synchrotron Radiation Facility (SSRF) storage ring is simulated under various conditions such as closed orbit distortion included, beam position monitor reading errors added, and finite-duration impulse-response filter strategy changed. (authors)

Status of the MIT-Bates South Hall Ring commissioning

International Nuclear Information System (INIS)

Flanz, J.B.; Jacobs, K.D.; McAllister, B.; Averill, R.; Bradley, S.; Carter, A.; Dow, K.; Farkondeh, M.; Ihloff, E.; Kowalski, S.

1993-01-01

The MIT-Bates South Hall Ring construction project is now nearly complete. At this time the Energy Compression System, the SHR Injection Line and the South Hall Ring itself are complete. The SHR Extraction Line is complete but has not been connected to the ring. Commissioning with beam of the completed beam lines has been started. The MIT-Bates South Hall Ring (SHR) is an electron storage ring used with the 1 GeV Bates electron accelerator to increase the effective duty factor and luminosity. A beam can be stored for use with an internal target, thus allowing for high duty factor, high luminosity experiments. External beams with high duty factor can be obtained using resonant extraction. The new systems associated with the SHR include the Energy Compression System (ECS), the Injection line, and the Extraction line. The authors have commissioned the ECS, the new injection line and the SHR without RF. This includes transporting beam, measuring beam phase space parameters using critical injection elements including a high voltage electrostatic septum, a fast beam kicker, and storing a beam in the SHR

Spin transitions in semiconductor quantum rings

International Nuclear Information System (INIS)

Baxevanis, Benjamin; Pfannkuche, Daniela

2010-01-01

We adopt the path integral Monte Carlo method to accurately resolve the total spin of the ground state of electrons confined in a quantum ring with different geometries. Using this method, an evaluation of the ground state of three electrons in a ring shows a spin transition to the fully polarized state by increasing the radius and thereby enhancing the Coulomb interaction. The total spin of the ground state is determined by the mutual interplay of confinement and electron-electron interaction. An analysis of the four-electron ring demonstrates that in this case no spin transitions take place. Furthermore, the effect of geometric distortion of the ring on its ground state has been investigated. Elliptically deforming the ring breaks the symmetry of the system and leads to the removal of orbital degeneracy. For strong distortion the splitting between hybridized states is sufficient to overcome the exchange-energy saving associated with a higher spin state. We have found that this effect removes the polarization of three electrons. Even in a four-electron ring the ground state is forced by the distortion to be unpolarized and thus suppressing the Hund's rule ground state.

Population size of Cuban Parrots Amazona leucocephala and Sandhill Cranes Grus canadensis and community involvement in their conservation in northern Isla de la Juventud, Cuba

Science.gov (United States)

Aguilera, X.G.; Alvarez, V.B.; Wiley, J.W.; Rosales, J.R.

1999-01-01

The Cuban Sandhill Crane Grus canadensis nesiotes and Cuban Parrot Amazona leucocephala palmarum are considered endangered species in Cuba and the Isla de la Juventud (formerly Isla de Pinos). Coincident with a public education campaign, a population survey for these species was conducted in the northern part of the Isla de la Juventud on 17 December 1995, from 06hoo to 10hoo. Residents from throughout the island participated, manning 98 stations, with 1-4 observers per station. Parrots were observed at 60 (61.2%) of the stations with a total of 1320, maximum (without correction for duplicate observations), and 1100, minimum (corrected), individuals counted. Sandhill cranes were sighted at 38 (38.8%) of the stations, with a total of 115 individuals. Cranes and parrots co-occurred at 20 (20.4%) of the stations.

A digital feedback system for transverse orbit stabilization in the NSLS rings

International Nuclear Information System (INIS)

Friedman, A.; Bozoki, E.

1993-01-01

We are reporting on the design and preliminary results of a prototype digital feedback system for the storage rings at the NSLS. the system will use a nolinear eigenvector decomposition algorithm. It will have a wide dynamic range and will be able to correct noise in the orbit over a bandwidth in excess of 60 Hz. A Motorola-162 CPU board is used to sample the PUE's at a minimum rate of 200 Hz and an HP-742rt board is used to read the sampled signals and to generate a correction signal for the orbit correctors

The vacuum system for the PEP II high energy ring straight sections

International Nuclear Information System (INIS)

Wienands, U.; Daly, E.; Heifets, S.A.; Kulikov, A.; Kurita, N.; Nordby, M.; Perkins, C.; Reuter, E.; Seeman, J.T.; Belser, F.C.; Berg, J.; Holdener, F.R.; Kerns, J.A.; McDaniel, M.R.; Stoeffl, W.

1995-01-01

The six straight sections of the PEP II High Energy Ring (HER) serve various functions: lattice tuning, beam injection and abort, providing space for rf cavities, longitudinal and transverse feedback, beam diagnostics and the interaction point. A stainless steel vacuum system has been designed; prototypes are currently being built. Cooling is required due to radiation coming from the last arc dipole and resistive losses in the vacuum chamber. Although the nominal beam current of the HER is 1 A the vacuum system is designed for 3 A to provide margin and an upgrade path. 5 refs., 7 figs

Ring coil optimization with respect to stress, temperature, and system energy over a range of physics requirements

International Nuclear Information System (INIS)

Pillsbury, R.D. Jr; Thome, R.J.

1987-01-01

The poloidal field coil system for a tokamak can be divided into the central solenoid and the ring coils. A ring coil is defined as one that has a small cross-section compared to its diameter. The size of the central solenoid is usually fixed very early in the design process since its size is directly related to the tokamak size. The sizes of the other (ring) coils are not as critical to determining the basic machine size. It is necessary to know their locations and currents in order to verify the shaping and position control of the plasma. Attention is usually focused only on the baseline plasma of the design point. However, the PF set must also be able to shape and maintain other plasmas. This paper describes a program which evaluates PF coil current scenarios over a range of physics requirements and determines the sizes of the coils necessary to satisfy constraints on the temperature rise and stress levels for the worst case scenario. In addition, the system energy requirements can be assessed and trade-offs between system energy and coil sizes (cost) can be made. Examples are given based on studies performed of CIT (Compact Ignition Tokamak)

Industrial property for science’s management, technology and innovation in Cuban State companies

Directory of Open Access Journals (Sweden)

Dulce María Contreras Villavicencio

2017-08-01

Full Text Available The paper synthesizes some research on industrial property aspects from the socio-legal perspective and financial accounting. Its focus to the socialist state enterprise adaptation in his economic fact, social and environmental responsibility as a fundamental Cuban model reach, competitiveness and high performance in socialist state enterprise. It outlines criteria on the ordering and implementation of industrial property through the management of science and technology, protection and dissemination of knowledge results as alternatives of regulation in chain of value to full cycle of innovation, dynamics of intangible heritage and relationships, exchange with marketing as business philosophy of business application. Strategies are proposed regarding the rights of this institution in the economic-organization management state.

Novel Fiber-Optic Ring Acoustic Emission Sensor.

Science.gov (United States)

Wei, Peng; Han, Xiaole; Xia, Dong; Liu, Taolin; Lang, Hao

2018-01-13

Acoustic emission technology has been applied to many fields for many years. However, the conventional piezoelectric acoustic emission sensors cannot be used in extreme environments, such as those with heavy electromagnetic interference, high pressure, or strong corrosion. In this paper, a novel fiber-optic ring acoustic emission sensor is proposed. The sensor exhibits high sensitivity, anti-electromagnetic interference, and corrosion resistance. First, the principle of a novel fiber-optic ring sensor is introduced. Different from piezoelectric and other fiber acoustic emission sensors, this novel sensor includes both a sensing skeleton and a sensing fiber. Second, a heterodyne interferometric demodulating method is presented. In addition, a fiber-optic ring sensor acoustic emission system is built based on this method. Finally, fiber-optic ring acoustic emission experiments are performed. The novel fiber-optic ring sensor is glued onto the surface of an aluminum plate. The 150 kHz standard continuous sinusoidal signals and broken lead signals are successfully detected by the novel fiber-optic ring acoustic emission sensor. In addition, comparison to the piezoelectric acoustic emission sensor is performed, which shows the availability and reliability of the novel fiber-optic ring acoustic emission sensor. In the future, this novel fiber-optic ring acoustic emission sensor will provide a new route to acoustic emission detection in harsh environments.

Conditioning of the vacuum system of the TPS storage ring without baking in situ

International Nuclear Information System (INIS)

Chan, C.K.; Chang, C.C.; Shueh, C.; Yang, I.C.; Wu, L.H.; Chen, B.Y.; Cheng, C.M.; Huang, Y.T.; Chuang, J.Y.; Cheng, Y.T.; Hsiao, Y.M.; Sheng, Albert

2017-01-01

To shorten the machine downtime, a maintenance procedure without baking in situ has been developed and applied to maintain and to upgrade the vacuum system of the TPS storage ring. The data of photon-stimulated desorption (PSD) reveal no obvious discrepancy between baking and not baking the vacuum system in situ. A beam-conditioning dose of extent only 11.8 A h is required to recover quickly the dynamic pressure of an unbaked vacuum system to its pre-intervention value according to the TPS maintenance experience.

Conditioning of the vacuum system of the TPS storage ring without baking in situ

Energy Technology Data Exchange (ETDEWEB)

Chan, C.K., E-mail: ckchan@nsrrc.org.tw; Chang, C.C.; Shueh, C.; Yang, I.C.; Wu, L.H.; Chen, B.Y.; Cheng, C.M.; Huang, Y.T.; Chuang, J.Y.; Cheng, Y.T.; Hsiao, Y.M.; Sheng, Albert

2017-04-11

To shorten the machine downtime, a maintenance procedure without baking in situ has been developed and applied to maintain and to upgrade the vacuum system of the TPS storage ring. The data of photon-stimulated desorption (PSD) reveal no obvious discrepancy between baking and not baking the vacuum system in situ. A beam-conditioning dose of extent only 11.8 A h is required to recover quickly the dynamic pressure of an unbaked vacuum system to its pre-intervention value according to the TPS maintenance experience.

Conditioning of the vacuum system of the TPS storage ring without baking in situ

Science.gov (United States)

Chan, C. K.; Chang, C. C.; Shueh, C.; Yang, I. C.; Wu, L. H.; Chen, B. Y.; Cheng, C. M.; Huang, Y. T.; Chuang, J. Y.; Cheng, Y. T.; Hsiao, Y. M.; Sheng, Albert

2017-04-01

To shorten the machine downtime, a maintenance procedure without baking in situ has been developed and applied to maintain and to upgrade the vacuum system of the TPS storage ring. The data of photon-stimulated desorption (PSD) reveal no obvious discrepancy between baking and not baking the vacuum system in situ. A beam-conditioning dose of extent only 11.8 A h is required to recover quickly the dynamic pressure of an unbaked vacuum system to its pre-intervention value according to the TPS maintenance experience.

New beam-position monitor system for upgraded Photon Factory storage ring.

Science.gov (United States)

Haga, K; Honda, T; Tadano, M; Obina, T; Kasuga, T

1998-05-01

Accompanying the brilliance-upgrading project at the Photon Factory storage ring, the beam-position monitor (BPM) system has been renovated. The new system was designed to enable precise and fast measurements to correct the closed-orbit distortion (COD), as well as to feed back the orbit position during user runs. There are 42 BPMs newly installed, amounting to a total of 65 BPMs. All of the BPMs are calibrated on the test bench using a coaxially strung metallic wire. The measured electrical offsets are typically 200 micro m in both directions, which is 1/2-1/3 of those of the old-type BPMs. In the signal-processing system, PIN diode switches are employed in order to improve reliability. In the fastest mode, this system is capable of measuring COD within about 10 ms; this fast acquisition will allow fast suppression of the beam movement for frequencies up to 50 Hz using a global feedback system.

Stability of large orbit, high-current particle rings

International Nuclear Information System (INIS)

Lovelace, R.V.E.

1994-01-01

A review is made of theory of the low-frequency stability of large orbit, high-current particle rings which continue to be of interest for compact fusion systems. The precession mode was the first mode predicted by Furth and observed by Christofilos to be unstable under certain conditions. Subsequently, many detailed studies have been made of the stability of particle rings- different modes, different ring geometries, systems with/without a toroidal B field, and sytems with/without a current carrying plasma component. The possibly dangerous modes are still thought to include the precession mode, the tilting mode, and the low order kink modes. copyright American Institute of Physics

Prevalence and Genotype Distribution of Pneumocystis jirovecii in Cuban Infants and Toddlers with Whooping Cough

Science.gov (United States)

Monroy-Vaca, Ernesto X.; de Armas, Yaxsier; Illnait-Zaragozí, María T.; Toraño, Gilda; Diaz, Raúl; Vega, Dania; Alvarez-Lam, Ileana; Calderón, Enrique J.

2014-01-01

This study describes the prevalence and genotype distribution of Pneumocystis jirovecii obtained from nasopharyngeal (NP) swabs from immunocompetent Cuban infants and toddlers with whooping cough (WC). A total of 163 NP swabs from 163 young Cuban children with WC who were admitted to the respiratory care units at two pediatric centers were studied. The prevalence of the organism was determined by a quantitative PCR (qPCR) assay targeting the P. jirovecii mitochondrial large subunit (mtLSU) rRNA gene. Genotypes were identified by direct sequencing of mtLSU ribosomal DNA (rDNA) and restriction fragment length polymorphism (RFLP) analysis of the dihydropteroate synthase (DHPS) gene amplicons. qPCR detected P. jirovecii DNA in 48/163 (29.4%) samples. mtLSU rDNA sequence analysis revealed the presence of three different genotypes in the population. Genotype 2 was most common (48%), followed in prevalence by genotypes 1 (23%) and 3 (19%); mixed-genotype infections were seen in 10% of the cases. RFLP analysis of DHPS PCR products revealed four genotypes, 18% of which were associated with resistance to sulfa drugs. Only contact with coughers (prevalence ratio [PR], 3.51 [95% confidence interval {CI}, 1.79 to 6.87]; P = 0.000) and exposure to tobacco smoke (PR, 1.82 [95% CI, 1.14 to 2.92]; P = 0.009) were statistically associated with being colonized by P. jirovecii. The prevalence of P. jirovecii in infants and toddlers with WC and the genotyping results provide evidence that this population represents a potential reservoir and transmission source of P. jirovecii. PMID:24131683

The cooperative a road for the economic and social development in the Cuban pattern

Directory of Open Access Journals (Sweden)

Claudio Alberto Rivera Rodríguez

2014-06-01

Full Text Available The present work has as purpose, to evaluate the antecedents, development, current situation and perspectives of the cooperative in the Cuban economic pattern. In the article, they are studied, from the antecedents of the emergence of the agricultural cooperative, until their stages, making emphasis in the problems that affect the normal development in these ways of property and administration in the objective and subjective order. Finally he/she is carried out a brief analysis of the emergence of the cooperatives in other sectors of the economy, evaluating the premises and importance of this transformation in the economic, productive and social order.

The treatment process of understanding scientific texts: A necessity in the current Cuban university

Directory of Open Access Journals (Sweden)

Yanet María Guerra Santana

2016-06-01

Full Text Available This work has as main purpose to emphasize the need for treatment of the process of understanding scientific texts in the university today, for the development of science and technology has placed at the forefront in every race the problem of processing scientific information. The ability to produce scientific texts has been somewhat spontaneity in the curriculum of professional training in Cuban university, which has resulted in some professionals do not yet have linguistic, discursive and strategic " tools " best to communicate the style of science, hence the study of the process of understanding of scientific texts in undergraduate currently constitute a need in our universities.

The Dynamical History of Chariklo and Its Rings

Energy Technology Data Exchange (ETDEWEB)

Wood, Jeremy [Hazard Community and Technical College, Community College Drive, Hazard, KY 41701 (United States); Horner, Jonti; Marsden, Stephen C. [Computational Engineering and Science Research Centre, University of Southern Queensland, West Street, Toowoomba, QLD 4350 (Australia); Hinse, Tobias C., E-mail: jeremy.wood@kctcs.edu [Korea Astronomy and Space Science Institute, 776 Daedukdae-ro, Yuseong-gu, Daejeon 305-348 (Korea, Republic of)

2017-06-01

Chariklo is the only small solar system body confirmed to have rings. Given the instability of its orbit, the presence of rings is surprising, and their origin remains poorly understood. In this work, we study the dynamical history of the Chariklo system by integrating almost 36,000 Chariklo clones backward in time for 1 Gyr under the influence of the Sun and the four giant planets. By recording all close encounters between the clones and planets, we investigate the likelihood that Chariklo’s rings could have survived since its capture to the Centaur population. Our results reveal that Chariklo’s orbit occupies a region of stable chaos, resulting in its orbit being marginally more stable than those of the other Centaurs. Despite this, we find that it was most likely captured to the Centaur population within the last 20 Myr, and that its orbital evolution has been continually punctuated by regular close encounters with the giant planets. The great majority (>99%) of those encounters within 1 Hill radius of the planet have only a small effect on the rings. We conclude that close encounters with giant planets have not had a significant effect on the ring structure. Encounters within the Roche limit of the giant planets are rare, making ring creation through tidal disruption unlikely.

Entanglement of distant superconducting quantum interference device rings

International Nuclear Information System (INIS)

Zukarnain, Z Ahmad; Konstadopoulou, A; Vourdas, A; Migliore, R; Messina, A

2005-01-01

We consider two distant mesoscopic SQUID rings, approximated with two-level systems, interacting with two-mode microwaves. The Hamiltonian of the system is used to calculate its time evolution. The cases with microwaves which at t = 0 are in separable states (classically correlated) or entangled states (quantum mechanically correlated) are studied. It is shown that the Josephson currents in the two SQUID rings are also correlated

Pulsed Power Applications in High Intensity Proton Rings

CERN Document Server

Zhang, Wu; Ducimetière, Laurent; Fowler, Tony; Kawakubo, Tadamichi; Mertens, Volker; Sandberg, Jon; Shirakabe, Yoshihisa

2005-01-01

The pulsed power technology has been applied in particle accelerators and storage rings for over four decades. It is most commonly used in injection, extraction, beam manipulation, source, and focusing systems. These systems belong to the class of repetitive pulsed power. In this presentation, we review and discuss the history, present status, and future challenge of pulsed power applications in high intensity proton accelerators and storage rings.

Some topics in beam dynamics of storage rings

International Nuclear Information System (INIS)

Mais, H.

1996-06-01

In the following report we want to review some beam dynamics problems in accelerator physics. Theoretical tools and methods are introduced and discussed, and it is shown how these concepts can be applied to the study of various problems in storage rings. The first part treats Hamiltonian systems (proton accelerators) whereas the second part is concerned with explicitly stochastic systems (e.g. electron storage rings). (orig.)

Hydra-Ring: a computational framework to combine failure probabilities

Science.gov (United States)

Diermanse, Ferdinand; Roscoe, Kathryn; IJmker, Janneke; Mens, Marjolein; Bouwer, Laurens

2013-04-01

This presentation discusses the development of a new computational framework for the safety assessment of flood defence systems: Hydra-Ring. Hydra-Ring computes the failure probability of a flood defence system, which is composed of a number of elements (e.g., dike segments, dune segments or hydraulic structures), taking all relevant uncertainties explicitly into account. This is a major step forward in comparison with the current Dutch practice in which the safety assessment is done separately per individual flood defence section. The main advantage of the new approach is that it will result in a more balanced prioratization of required mitigating measures ('more value for money'). Failure of the flood defence system occurs if any element within the system fails. Hydra-Ring thus computes and combines failure probabilities of the following elements: - Failure mechanisms: A flood defence system can fail due to different failure mechanisms. - Time periods: failure probabilities are first computed for relatively small time scales (assessment of flood defense systems, Hydra-Ring can also be used to derive fragility curves, to asses the efficiency of flood mitigating measures, and to quantify the impact of climate change and land subsidence on flood risk. Hydra-Ring is being developed in the context of the Dutch situation. However, the computational concept is generic and the model is set up in such a way that it can be applied to other areas as well. The presentation will focus on the model concept and probabilistic computation techniques.

Quality of life in a group of Cuban women with breast cancer

International Nuclear Information System (INIS)

Izquierdo-Gonzalez, Marlen

2009-01-01

Was studied a group of 16 Cuban patients, undergoing surgery and treatment for breast cancer oncospecific with survival greater than anno to assess the impact of the diagnosis, surgery and concomitant treatment on quality of life. The quality of life in the study group is similar to that of reference groups and other breast cancer patients with more than one year of survival, with better physical functioning. The evaluation of the exponents of emotional state, such as nervousness, worry, irritability and depression, showed that the evaluation of the quality of the emotional scale offers significantly lower values of other country groups, but corresponds with that reported for women with breast cancer survival time with the same and equal to the value obtained for cancer patients in treatment and less than a year survival. (Author)

A Wireless Fatigue Monitoring System Utilizing a Bio-Inspired Tree Ring Data Tracking Technique

OpenAIRE

Bai, Shi; Li, Xuan; Xie, Zhaohui; Zhou, Zhi; Ou, Jinping

2014-01-01

Fatigue, a hot scientific research topic for centuries, can trigger sudden failure of critical structures such as aircraft and railway systems, resulting in enormous casualties as well as economic losses. The fatigue life of certain structures is intrinsically random and few monitoring techniques are capable of tracking the full life-cycle fatigue damage. In this paper, a novel in-situ wireless real-time fatigue monitoring system using a bio-inspired tree ring data tracking technique is propo...

White Ring; White ring

Energy Technology Data Exchange (ETDEWEB)

Aoki, H.; Yuzawa, H. [Nikken Sekkei Ltd., Osaka (Japan)

1998-01-05

White Ring is a citizen`s gymnasium used for figure skating and short track speed skating games of 18th Winter Olympic Games in 1998. White Ring is composed of a main-arena and a sub-arena. For the main-arena with an area 41mtimes66m, an ice link can be made by disengaging the potable floor and by flowing brine in the bridged polystyrene pipes embedded in the concrete floor. Due to the fortunate groundwater in this site, well water is used for the outside air treatment energy in 63% during heating and in 35% during cooling. Ammonia is used as a cooling medium for refrigerating facility. For the heating of audience area in the large space, heat load from the outside is reduced by enhancing the heat insulation performance of the roof of arena. The audience seats are locally heated using heaters. For the White Ring, high quality environment is realized for games through various functions of the large-scale roof of the large space. Success of the big event was expected. 15 figs., 4 tabs.

Token Ring Project

Directory of Open Access Journals (Sweden)

Adela Ionescu

2007-01-01

Full Text Available Ring topology is a simple configuration used to connect processes that communicate among themselves. A number of network standards such as token ring, token bus, and FDDI are based on the ring connectivity. This article will develop an implementation of a ring of processes that communicate among themselves via pipe links. The processes are nodes in the ring. Each process reads from its standard input and writes in its standard output. N-1 process redirects the its standard output to a standard input of the process through a pipe. When the ring-structure is designed, the project can be extended to simulate networks or to implement algorithms for mutual exclusion

Semi-algebraic function rings and reflectors of partially ordered rings

CERN Document Server

Schwartz, Niels

1999-01-01

The book lays algebraic foundations for real geometry through a systematic investigation of partially ordered rings of semi-algebraic functions. Real spectra serve as primary geometric objects, the maps between them are determined by rings of functions associated with the spectra. The many different possible choices for these rings of functions are studied via reflections of partially ordered rings. Readers should feel comfortable using basic algebraic and categorical concepts. As motivational background some familiarity with real geometry will be helpful. The book aims at researchers and graduate students with an interest in real algebra and geometry, ordered algebraic structures, topology and rings of continuous functions.

Status of /hacek C/erenkov Ring Imaging systems

International Nuclear Information System (INIS)

Leith, D.W.G.S.

1987-06-01

Cerenkov Ring Imaging is briefly introduced, and the problems or choices of designing such a counter are discussed. Recent results from the DELPHI and SLD prototype are presented and compared to the expected performances. 13 refs., 33 figs., 2 tabs

Status of /hacek C/erenkov Ring Imaging systems

Energy Technology Data Exchange (ETDEWEB)

Leith, D.W.G.S.

1987-06-01

Cerenkov Ring Imaging is briefly introduced, and the problems or choices of designing such a counter are discussed. Recent results from the DELPHI and SLD prototype are presented and compared to the expected performances. 13 refs., 33 figs., 2 tabs.

Approaches to Climate Change & Health in Cuba: Guillermo Mesa MD MPhil, Director, Disasters & Health, National School of Public Health. Paulo Ortiz MS PhD, Senior Researcher, Climate Center, Cuban Meteorology Institute.

Science.gov (United States)

Mesa, Guillermo; Ortiz, Paulo; Gorry, Conner

2015-04-01

The US National Institutes of Health predict climate change will cause an additional 250,000 deaths between 2030 and 2050, with damages to health costing US$2-$4 billion by 2030. Although much debate still surrounds climate change, island ecosystems-such as Cuba's-in the developing world are arguably among the most vulnerable contexts in which to confront climate variability. Beginning in the 1990s, Cuba launched research to develop the evidence base, set policy priorities, and design mitigation and adaptation actions specifically to address climate change and its effects on health. Two researchers at the forefront of this interdisciplinary, intersectoral effort are epidemiologist Dr Guillermo Mesa, who directed design and implementation of the nationwide strategy for disaster risk reduction in the Cuban public health system as founding director of the Latin American Center for Disaster Medicine (CLAMED) and now heads the Disasters and Health department at the National School of Public Health; and Dr Paulo Ortiz, a biostatistician and economist at the Cuban Meteorology Institute's Climate Center (CENCLIM), who leads the research on Cuba's Climate and Health project and is advisor on climate change and health for the UN Economic Commission for Latin America and the Caribbean (ECLAC).

Cuban experience with the therapeutic use of adult stem cells

International Nuclear Information System (INIS)

Hernandez Ramirez, Porfirio; Alfonso Simon, Amel; Aparicio Suarez, Jose L

2011-01-01

The basic and clinical researches carried out during past years on the stem cells and its therapeutic possibilities are at present times, one of the most interesting subjects of the contemporaneous medicine. There are advances in the study and application of adult stem cells showing remarkable advantages on the embryonic ones, since its handling is more simple, economic and they are obtained from the own subject to be treated. For the introduction in Cuba of the regenerative cellular therapy in the Institute of Hematology and Immunology the cellular sources selected were the adult stem cells derived from bone marrow and the mobilized ones to the peripheral blood. To make easy the expansion of treatment to other hospital centers, authors standardized a technique for the mobilization of the hematopoietic stem cells to peripheral blood using a granulocyte colony-stimulating factor (Filgrastim, of national production) developing a simple, economic and more tolerable method for patients. In this way, the cellular therapy has been expanded to 6 Cuban provinces and until April, 2009 562 cases with autologous adult stem cells transplant have been treated, from which the 81.7% to correspond to patients presenting with Angiology diseases with a significant reduction of major amputations. Also, the results have been very promising in the bone lesions and periodontal processes among other diseases treated. The results obtained until now may be considered as a new achievement of revolutionary science and of our national health systems and of science and technique. The method used is an economic and feasible procedure for the institutions with scarce resources

Nonlinear dynamics aspects of modern storage rings

International Nuclear Information System (INIS)

Helleman, R.H.G.; Kheifets, S.A.

1986-01-01

It is argued that the nonlinearity of storage rings becomes an essential problem as the design parameters of each new machine are pushed further and further. Yet the familiar methods of classical mechanics do not allow determination of single particle orbits over reasonable lengths of time. It is also argued that the single particle dynamics of a storage ring is possibly one of the cleanest and simplest nonlinear dynamical systems available with very few degrees of freedom. Hence, reasons are found for accelerator physicists to be interested in nonlinear dynamics and for researchers in nonlinear dynamics to be interested in modern storage rings. The more familiar methods of treating nonlinear systems routinely used in acclerator theory are discussed, pointing out some of their limitations and pitfalls. 39 refs., 1 fig

The dynamics of rings around small, irregular bodies

Science.gov (United States)

Sicardy, Bruno

2017-06-01

Stellar occultations revealed the presence of two dense rings around the Centaur object (10199) Chariklo (Braga-Ribas et al., Nature 508, 72, 2014). This is the first ring system discovered around an object that is not a giant planet, suggesting that rings may exist around numerous bodies in the solar system. Chariklo's rings roughly reside at the outer limit of the Roche zone of the body. Moreover, the main ring has sharp edges, which call for the presence of putative shepherd satellites. Those characteristics give an image of Chariklo's rings that are rather similar, in terms of dynamics, to those surrounding the gaseous planets.An important difference exists, however, between giant planets and small bodies: the formers are highly axisymmetric, while the latters can support mass anomalies (eg surface topographic features) or non-spherical shapes (eg an ellipsoidal figure of equilibrium) that involve masses, relative to the body itself, as large as 10-4-10-3.We investigate the effect of non-axisymmetric terms in the potential of the body upon a collisional debris disk that initially surrounds a small irregular body. We show that the corotation points being maxima of energy, dissipative collisions remove the particles from the corotation zone over short time scales (< 106 years). Moreover, the Lindblad resonances inside the corotation radius create torques that drive the particles onto the surface of the central body. Conversely, the outer Lindblad resonances push the disk material beyond the outer 3/2 and 2/1 Lindblad resonances.Taking as an example Chariklo's ring system, for which recent data have been obtained from stellar occultations, we show that the Lindblad resonant torques actuate over short time scales (< 106 years). This general picture offers a natural explanation of the presence of dense rings at the outer limit of Chariklo's Roche zone, and their absence closer to the body.The work leading to this results has received funding from the European

Experience with the New Digital RF Control System at the CESR Storage Ring

CERN Document Server

Liepe, Matthias; Dobbins, John; Kaplan, Roger; Strohman, Charles R; Stuhl, Benjamin K

2005-01-01

A new digital control system has been developed, providing great flexibility, high computational power and low latency for a wide range of control and data acquisition applications. This system is now installed in the CESR storage ring and stabilizes the vector sum field of two of the superconducting CESR 500 MHz cavities and the output power from the driving klystron. The installed control system includes in-house developed digital and RF hardware, very fast feedback and feedforward control, a state machine for automatic start-up and trip recovery, cw and pulsed mode operation, fast quench detection, and cavity frequency control. Several months of continuous operation have proven high reliability of the system. The achieved field stability surpasses requirements.

The control systems for the CERN Super Proton Synchrotron ring power supplies

CERN Document Server

Kuhn, H K

1981-01-01

The dedicated control system for the 16 voltage-controlled Main Ring pulsed supplies, allowing the reproduction of the desired B and Q fields to better than +or-2*10/sup -4/ at injection is described. It outlines both the hardware (smoothed function generators) and software side. Current measurements via DVMs or the B train off the reference magnets are used as inputs to the correction algorithm which is based on successive approximation. The algorithm enables the machine operators to trim selectively both the closed orbit and/or the betatron wave number of the machine within 1 to a few cycles. The control system related computer memory requirements are given. (0 refs).

Synthesis of a new class of fused cyclotetraphosphazene ring systems.

Science.gov (United States)

Beşli, Serap; Mutlu, Ceylan; İbişoğlu, Hanife; Yuksel, Fatma; Allen, Christopher W

2015-01-05

Octachlorocyclotetraphosphazene (1) was reacted with butylamines [n-butyl, i-butyl, sec-butyl, and t-butyl] in a 1:0.8 mol ratio in THF to obtain cyclotetraphosphazenes bearing a P-NH group, N4P4Cl7(NHR) [R = n-butyl (2a), i-butyl (2b), sec-butyl (2c), t-butyl (2d)](2a-d). The cyclotetraphosphazene derivatives 2a, 2b, and 2c were treated with sodium hydride giving rise to a new type of cyclophosphazene compounds (P8N8 ring) consisting of three fused tetramer rings (3a-c). Whereas reaction of sodium hydride with the t-butylaminocyclophosphazene derivative (2d) gave a P-O-P bridged compound (4) presumably as a result of hydrolysis reaction associated with moisture in the solvent. It is likely that the 16-membered cyclooctaphosphazene derivatives (3a-c) are formed by a proton abstraction/chloride ion elimination, intramolecular nucleophilic attack, ring opening and intermolecular condensation processes, respectively.

Rotating ring-ring electrode theory and experiment

NARCIS (Netherlands)

Kuiken, H.K.; Bakkers, E.P.A.M.; Ligthart, H.; Kellyb, J.J.

2000-01-01

A model is presented for the rotating ring-ring electrode. Although the electrode is defined by four characteristic lengths, it is shown that the collection efficiency depends on only two dimensionless parameters. A simple relationship between these and the corresponding parameters for the rotating

The suitability of annual tree growth rings as environmental archives: Evidence from Sr, Nd, Pb and Ca isotopes in spruce growth rings from the Strengbach watershed

Science.gov (United States)

Stille, Peter; Schmitt, Anne-Désirée; Labolle, François; Pierret, Marie-Claire; Gangloff, Sophie; Cobert, Florian; Lucot, Eric; Guéguen, Florence; Brioschi, Laure; Steinmann, Marc; Chabaux, François

2012-05-01

The combination of the Sr, Nd and Pb isotope systems, recognized as tracers of sources, with the Ca isotope system, known to reveal biology-related fractionations, allowed us to test the reliability of spruce (Picea abies) growth rings as environmental archives through time (from 1916 to 1983) in a forest ecosystem affected by acid atmospheric deposition. Sr and Pb isotopes have already been applied in former tree-ring studies, whereas the suitability of Nd and Ca isotope systems is checked in the present article. Our Sr and Nd isotope data indicate an evolution in the cation origin with a geogenic origin for the oldest rings and an atmospheric origin for the youngest rings. Ca isotopes show, for their part, an isotopic homogeneity which could be linked to the very low weathering flux of Ca. Since this flux is weak the spruces' root systems have pumped the Ca mainly from the organic matter-rich top-soil over the past century. In contrast, the annual growth rings studied are not reliable and suitable archives of past Pb pollution.

Novel Fiber-Optic Ring Acoustic Emission Sensor

Directory of Open Access Journals (Sweden)

Peng Wei

2018-01-01

Full Text Available Acoustic emission technology has been applied to many fields for many years. However, the conventional piezoelectric acoustic emission sensors cannot be used in extreme environments, such as those with heavy electromagnetic interference, high pressure, or strong corrosion. In this paper, a novel fiber-optic ring acoustic emission sensor is proposed. The sensor exhibits high sensitivity, anti-electromagnetic interference, and corrosion resistance. First, the principle of a novel fiber-optic ring sensor is introduced. Different from piezoelectric and other fiber acoustic emission sensors, this novel sensor includes both a sensing skeleton and a sensing fiber. Second, a heterodyne interferometric demodulating method is presented. In addition, a fiber-optic ring sensor acoustic emission system is built based on this method. Finally, fiber-optic ring acoustic emission experiments are performed. The novel fiber-optic ring sensor is glued onto the surface of an aluminum plate. The 150 kHz standard continuous sinusoidal signals and broken lead signals are successfully detected by the novel fiber-optic ring acoustic emission sensor. In addition, comparison to the piezoelectric acoustic emission sensor is performed, which shows the availability and reliability of the novel fiber-optic ring acoustic emission sensor. In the future, this novel fiber-optic ring acoustic emission sensor will provide a new route to acoustic emission detection in harsh environments.

Cuban regulatory politics with relationship to the Radioactive lightning rod employment

International Nuclear Information System (INIS)

Lopez Forteza; Yamil; Jerez Vegueria, Pablo F.; Quevedo Garcia, Jose R.; Diaz Guerra, Pedro; Dumenigo Gonzalez, Cruz

2003-01-01

The radioactive lightning rod employment for the protection of facilities against atmospheric discharges reached its maximum splendor in the years 80. It was in fact at the end of this decade when the technical considerations arose, with relationship to the justification of this practice that finally took to that the production of such teams was abolished. For the regulatory authorities, however, it continues having validity the question related with the control of those lightning rod that you/they stay in use, as well as the relative one to the establishment of a coherent national politics with the international practice. Presently work the results of the last 10 years of control of the radioactive lightning rod use are presented in Cuba and the radiological evaluation carried out on the base of this experience. Lastly, it exposes the Cuban regulatory politics established with relationship to the employment of this teams in the country

Bimodality and the formation of Saturn's ring particles

International Nuclear Information System (INIS)

Gehrels, T.

1980-01-01

The F ring appears to have an outer and an inner rim, with only the latter observed by the imaging photopolarimeter (IPP) on the Pioneer Saturn spacecraft. The inside of the G ring, near 2.49 R/sub S/, may also be seen in the optical data. 1979S1 is red as well as dark. The light scattered through the B ring is noticeably red. The A ring has a dense outer rim. The Cassini Division and the French Division (Dollfus Division) have a dark gap near their centers. The C ring becomes weaker toward the center such that outer, middle, and inner C rings can be recognized. The Pioneer and earth-based observations are explained with a model for the B and A rings to some extent of a bimodal size distributions of particles; the larger ones may be original accretions, while small debris diffuses inward through the Cassini Division and the C ring. During the formation of the ring system, differential gravitation allowed only silicaceous grains of higher density (rho> or approx. =3 g cm -3 ) to coagulate. These serve as interstitial cores for snowy carbonaceous grains, between the times of accretion from interplanetary cometary grains and liberation by collision followed by diffusion inward to Saturn and final evaporation

Isomorphism Theorem on Vector Spaces over a Ring

Directory of Open Access Journals (Sweden)

Futa Yuichi

2017-10-01

Full Text Available In this article, we formalize in the Mizar system [1, 4] some properties of vector spaces over a ring. We formally prove the first isomorphism theorem of vector spaces over a ring. We also formalize the product space of vector spaces. ℤ-modules are useful for lattice problems such as LLL (Lenstra, Lenstra and Lovász [5] base reduction algorithm and cryptographic systems [6, 2].

Vacuum system design for the PEP-II B Factory High-Energy Ring

International Nuclear Information System (INIS)

Perkins, C.; Bostic, D.; Daly, E.

1994-06-01

The design of the vacuum system for the PEP-II B Factory High-Energy Ring is reviewed. The thermal design and vacuum requirements are particularly challenging in PEP-II due to high stored beam currents up to 3.0 amps in 1658 bunches. The vacuum chambers for the HER arcs are fabricated by electron beam welding extruded copper sections up to 6 m long. Design of these chambers and the vacuum PumPing configuration is described with results from vacuum and thermal analyses

Commissioning results of the APS storage ring diagnostics systems

International Nuclear Information System (INIS)

Lumpkin, A.H.

1996-01-01

Initial commissionings of the Advanced Photon Source (APS) 7-GeV storage ring and its diagnostics systems have been done. Early studies involved single-bunch measurements for beam transverse size (σ x ∼ 150 μm, σ y ∼ 50 μm), current, injection losses, and bunch length. The diagnostics have been used in studies related to the detection of an extra contribution to beam jitter at ∼ 6.5 Hz frequency; observation of bunch lengthening (σ ∼ 30 to 60 ps) with single-bunch current; observation of an induced vertical, head-tail instability; and detection of a small orbit change with insertion device gap position. More recently, operations at 100-mA stored-beam current, the baseline design goal, have been achieved with the support of beam characterizations

Conceptual design of a linac-stretcher ring to obtain a 2-gev continuous electron beam

International Nuclear Information System (INIS)

Cho, Y.; Holt, R.J.; Jackson, H.E.; Khoe, T.K.; Mavrogenes, G.S.

1981-01-01

In order to obtain a high duty factor, >100 /mu/A 2-Gev electron beam, a linac-stretcher ring system was designed. The system is an attractive option because it draws heavily on the existing accelerator technology. The linac-stretcher ring consists of a 2-Gev SLAC-type pulsed linac which injects into a storage ring. In between linac pulses, the stored electron beam is to extract resonantly. This design differs from those discussed recently in several important respects. The storage ring includes an rf system whose purpose is to control the beam orbit and rate of extraction from the ring. With an rf system in the ring, the injection scheme consists of a few turns of synchronous transfers of beam between the linac and storage ring. 4 refs

Solar system history as recorded in the Saturnian ring structure

International Nuclear Information System (INIS)

Alfven, H.

1983-04-01

The paper is based on Holbergs analysis of the Voyager photographs in both reflected and transparent light, combined with occulation data of stars seen through the rings. Besides rapidly varying phenomena (spokes, braided ring, etc.), which according to Mendis are due to gravito-electromagnetic effects, the ring consists of a bulk structure, a fine structure, and also a hyperfine structure, showing more than 10000 ringlets. The large number of ringlets can be explained by the Baxter-Thompson negative diffusion. This gives the ringlets a stability which makes it possible to interprete them as fossils, which originated at cosmogonic times. It is shown that the bulk structure can be explained by the combined cosmogonic shadows of the satellites Mimas, Janus (co-orbiting satellites) and the Shepherd satellites. This structure originated at the transition from the plasma phase to the planetesimal phase (which probably took place 4-5 times 10 9 years ago). Further, Holberg has discovered that the shadows are not simple void regions but exhibit a certain characteristic signature. This is not yet understood theoretically. Parts of the fine structure are explained by Holberg as resonances with the satellites. Parts are here interpreted as cosmogonic shadow effects. However, there are a number of ringlets which can neither be explained by cosmogonic nor by resonance effects. The most important conclusion is that an analysis of the ring data is liekly to lead to a reconstruction of the plasma-planetesimal transition with an accuracy of a few percent. (author)

Carbonatite ring-complexes explained by caldera-style volcanism.

Science.gov (United States)

Andersson, Magnus; Malehmir, Alireza; Troll, Valentin R; Dehghannejad, Mahdieh; Juhlin, Christopher; Ask, Maria

2013-01-01

Carbonatites are rare, carbonate-rich magmatic rocks that make up a minute portion of the crust only, yet they are of great relevance for our understanding of crustal and mantle processes. Although they occur in all continents and from Archaean to present, the deeper plumbing system of carbonatite ring-complexes is usually poorly constrained. Here, we show that carbonatite ring-complexes can be explained by caldera-style volcanism. Our geophysical investigation of the Alnö carbonatite ring-complex in central Sweden identifies a solidified saucer-shaped magma chamber at ~3 km depth that links to surface exposures through a ring fault system. Caldera subsidence during final stages of activity caused carbonatite eruptions north of the main complex, providing the crucial element to connect plutonic and eruptive features of carbonatite magmatism. The way carbonatite magmas are stored, transported and erupt at the surface is thus comparable to known emplacement styles from silicic calderas.

Kayser-Fleischer Rings

Science.gov (United States)

... Support Contacts Lab Tracker/Copper Calculator Stories Programs & Research ... About Everything you need to know about Wilson Disease Kayser-Fleischer Rings Definition Kayser-Fleischer Ring: Clinical sign. Brownish-yellow ring visible around the corneo- ...

Adiabatic compression of ion rings

International Nuclear Information System (INIS)

Larrabee, D.A.; Lovelace, R.V.

1982-01-01

A study has been made of the compression of collisionless ion rings in an increasing external magnetic field, B/sub e/ = zB/sub e/(t), by numerically implementing a previously developed kinetic theory of ring compression. The theory is general in that there is no limitation on the ring geometry or the compression ratio, lambdaequivalentB/sub e/ (final)/B/sub e/ (initial)> or =1. However, the motion of a single particle in an equilibrium is assumed to be completely characterized by its energy H and canonical angular momentum P/sub theta/ with the absence of a third constant of the motion. The present computational work assumes that plasma currents are negligible, as is appropriate for a low-temperature collisional plasma. For a variety of initial ring geometries and initial distribution functions (having a single value of P/sub theta/), it is found that the parameters for ''fat'', small aspect ratio rings follow general scaling laws over a large range of compression ratios, 1 3 : The ring radius varies as lambda/sup -1/2/; the average single particle energy as lambda/sup 0.72/; the root mean square energy spread as lambda/sup 1.1/; and the total current as lambda/sup 0.79/. The field reversal parameter is found to saturate at values typically between 2 and 3. For large compression ratios the current density is found to ''hollow out''. This hollowing tends to improve the interchange stability of an embedded low β plasma. The implications of these scaling laws for fusion reactor systems are discussed

Warden’s Five-Ring System Theory: Legitimate Wartime Military Targeting or an Increased Potential to Violate the Law and Norms of Expected Behavior?

Science.gov (United States)

2000-04-01

the five-ring system theory that dramatically improves the warfighters ability to systematically identify wartime targets. However, for all of its...acclaim, little has been written about Warden’s five-ring system theory . Even less has been written about the legal and moral implications of using Warden’s theory to identify wartime targets.

James Webb Space Telescope Observations of Stellar Occultations by Solar System Bodies and Rings

Science.gov (United States)

Santos-Sanz, P.; French, R. G.; Pinilla-Alonso, N.; Stansberry, J.; Lin, Z-Y.; Zhang, Z-W.; Vilenius, E.; Mueller, Th.; Ortiz, J. L.; Braga-Ribas, F.;

The Cryogenic Storage Ring CSR

OpenAIRE

von Hahn, Robert; Becker, Arno; Berg, Felix; Blaum, Klaus; Breitenfeldt, Christian; Fadil, Hisham; Fellenberger, Florian; Froese, Michael; George, Sebastian; Göck, Jürgen; Grieser, Manfred; Grussie, Florian; Guerin, Elisabeth A.; Heber, Oded; Herwig, Philipp

2016-01-01

An electrostatic cryogenic storage ring, CSR, for beams of anions and cations with up to 300 keV kinetic energy per unit charge has been designed, constructed, and put into operation. With a circumference of 35 m, the ion-beam vacuum chambers and all beam optics are in a cryostat and cooled by a closed-cycle liquid helium system. At temperatures as low as (5.5 ± 1) K inside the ring, storage time constants of several minutes up to almost an hour were observed for atomic and molecular, anion a...

The Lord of Rings - the mysterious case of the stolen rings: a critical analysis of an informal education activity

Science.gov (United States)

Sandrelli, S.

2011-10-01

"The Lord of Rings - the mysterious case of the stolen rings" is a live astronomical role-playing game for kids aged 10 -13 [1]. Its goal is to introduce them to some of the main topics of the Solar System: a) the role of gravity; b) the distribution of mass & light; c) the effects of rotation; d) the distribution of water. The game was held at several Science Festival in Italy (Perugia, Genova, Fiorano, Bologna) obtaining great success. Teams of about 6-8 members are introduced to Mr Schioppanelli, the astro-detective of the town (the name is a pun: it reminds Schiaparelli, the famous italian astronomer, and it is a slang expression meaning "ring-breaker"). Mr Schioppanelli has his office in an "gastronomical astronomical observatory", known as The Red Giant Pizzeria. Schioppanelli informs the kids that a mysterious Centaur succeded in stealing the rings of Saturn. The partecipants are appointed astro-detectives incharge and asked to find the rings by browsing around the Solar System, which is scaled so as to fit the town historical centre or a pedestrian area, going from the Sun to Saturn or beyond, depending on the actual area at disposal. Great care must be taken allowing children playing only in a car-free area of the town. At the right scaled distances, the partecipants meet characters playing as the various planets. The kids can talk to them after solving a riddle, obtaining useful informations. A special characters play as a comet, timely going in and out of the inner solar system. The teams can also talk to some shepherdmoons of the rings. They easily discover that the rings were totally destroyed by the Centaur: a real disaster! They are also suggested to gather the necessary ingredients (gravity, light, rotation, inclination, dust and water, represented by simple objects like apples, spinning tops and so on) to rebuild the rings. The kids can buy the ingredients from different planets: every planet has ingredients in quantities which are proportionate to

1393 Ring Bus at JPL: Description and Status

Science.gov (United States)

Wysocky, Terry R.

2007-01-01

Completed Ring Bus IC V&V Phase - Ring Bus Test Plan Completed for SIM Project - Applicable to Other Projects Implemented a Avionics Bus Based upon the IEEE 1393 Standard - Excellent Starting Point for a General Purpose High-Speed Spacecraft Bus - Designed to Meet SIM Requirements for - Real-time deterministic, distributed systems. - Control system requirements - Fault detection and recovery Other JPL Projects Considering Implementation F'light Software Ring Bus Driver Module Began in 2006, Continues Participating in Standard Revision. Search for Earth-like planets orbiting nearby stars and measure the masses and orbits of the planets it finds. Survey 2000 nearby stars for planetary systems to learn whether our Solar System is unusual, or typical. Make a new catalog of star position 100 times more accurate than current measurements. Learn how our galaxy formed and will evolve by studying the dynamics of its stars. Critically test models of exactly how stars shine, including exotic objects like black holes, neutron stars and white dwarfs.

The positron accumulator ring for the APS

International Nuclear Information System (INIS)

Crosbie, E.A.

1989-01-01

The Positron Accumulator Ring (PAR) is designed to accumulate and damp positrons from the 450-MeV linac during the 0.5-s cycle time of the injector synchrotron for the APS 7-GeV storage ring. During 0.4 s of each synchrotron cycle, up to 24 linac pulses are injected into the horizontal phase space of the PAR at a 60-Hz rate. Each injected pulse occupies about 1.3 of the circumference of the accumulator ring. After 0.1 s for longitudinal damping, the single accumulated bunch is transferred to one of the 353-MHz buckets of the injector synchrotron RF system. The bunch is accelerated to 7 GeV and transferred to the storage ring, while the PAR accumulates the next bunch of positrons. 2 refs., 3 figs., 2 tabs

The positron accumulator ring for the APS

International Nuclear Information System (INIS)

Crosbie, E.A.

1989-01-01

The Positron Accumulator Ring (PAR) is designed to accumulate and damp positrons from the 450-MeV linac during the 0.5-s cycle time of the injector synchrotron for the APS 7-GeV storage ring. During 0.4 s of each synchrotron cycle, up to 24 linac pulses are injected into the horizontal phase space of the PAR at a 60-Hz rate. Each injected pulse occupies about 1/3 of the circumference of the accumulator ring. After 0.1 s for longitudinal damping, the single accumulated bunch is transferred to one of the 353-MHz buckets of the injector synchrotron RF system. The bunch is accelerated to 7 GeV and transferred to the storage ring, while the PAR accumulates the next bunch of positrons. 2 refs., 3 figs., 2 tabs

Energy of Intramolecular Hydrogen Bonding in ortho-Hydroxybenzaldehydes, Phenones and Quinones. Transfer of Aromaticity from ipso-Benzene Ring to the Enol System(s

Directory of Open Access Journals (Sweden)

Danuta Rusinska-Roszak

2017-03-01

Full Text Available Intramolecular hydrogen bonding (HB is one of the most studied noncovalent interactions of molecules. Many physical, spectral, and topological properties of compounds are under the influence of HB, and there are many parameters used to notice and to describe these changes. Hitherto, no general method of measurement of the energy of intramolecular hydrogen bond (EHB has been put into effect. We propose the molecular tailoring approach (MTA for EHB calculation, modified to apply it to Ar-O-H∙∙∙O=C systems. The method, based on quantum calculations, was checked earlier for hydroxycarbonyl-saturated compounds, and for structures with resonance-assisted hydrogen bonding (RAHB. For phenolic compounds, the accuracy, repeatability, and applicability of the method is now confirmed for nearly 140 structures. For each structure its aromaticity HOMA indices were calculated for the central (ipso ring and for the quasiaromatic rings given by intramolecular HB. The comparison of calculated HB energies and values of estimated aromaticity indices allowed us to observe, in some substituted phenols and quinones, the phenomenon of transfer of aromaticity from the ipso-ring to the H-bonded ring via the effect of electron delocalization.

Introduction to the magnet and vacuum systems of an electron storage ring

International Nuclear Information System (INIS)

Weng, W.T.

1982-01-01

An accelerator or storage ring complex is a concerted interplay of various functional systems. For the convenience of discussion we can divide it into the following systems: injector, magnet, RF, vacuum, instrumentation and control. In addition, the conventional construction of the building and radiation safety consideration are also needed and finally the beam lines, detector, data acquisition and analysis set-ups for research programs. Dr. L. Teng has given a comprehensive review of the whole complex and the operation of such a facility. I concentrate on the description of magnet and vacuum systems. Only the general function of each system and the basic design concepts will be introduced, no detailed engineering practice will be given which will be best done after a machine design is produced. For further understanding and references a table of bibliography is provided at the end of the paper

Fano resonance and persistent current of a quantum ring

International Nuclear Information System (INIS)

Xiong Yongjian; Liang Xianting

2004-01-01

We investigate electron transport and persistent current of a quantum ring weakly attached to current leads. Assuming there is direct coupling (weakly or strongly) between two leads, electrons can transmit by the inter-lead coupling or tunneling through the quantum ring. The interference between the two paths yields asymmetric Fano line shape for conductance. In presence of interior magnetic flux, there is persistent current along the ring with narrow resonance peaks. The positions of the conductance resonances and the persistent current peaks correspond to the quasibound levels of the closed ring. This feature is helpful to determine the energy spectrum of the quantum ring. Our results show that the proposed setup provides a tunable Fano system

The behavior of the planetary rings under the Kozai Mechanism

Science.gov (United States)

Sucerquia, M. A.; Ramírez, C. V.; Zuluaga, J. I.

2017-07-01

Rings are one of the main feature of almost all giant planets in the Solar System. Even though thousands of exoplanets have been discovered to date, no evidence of exoplanetary rings have been found despite the effort made in the development and enhancing of techniques and methods for direct or indirect detection. In the transit of a ringed planet, the dynamic of the ring itself could play a meaningful role due to the so called Kozai Mechanism (KM) acting on each particle of it. When some specific initial conditions of the ring are fulfilled (as a ring inclination greater than ˜ 39°), KM generates short periodic changes in the inclination and eccentricity of each particle, leading to a meaningful characteristic collective behavior of the ring: it changes its width, inclination and optical depth. These changes induce periodic variations on the eclipsed area of the parent star, generating slight changes in the observed transit signal. Under this mechanism, light curves depths and shapes oscillate according to the fluctuations of the ring. To show this effect we have performed numerical simulations of the dynamic of a system of particles to asses the ring inclination and width variations over time. We have calculated the expected variations in the transit depth and finally, we have estimated the effect on the light curve of a hypothetical ringed exoplanet affected by the KM. The detection of this effect could be used as an alternative method to detect/confirm exoplanetary rings, and also it could be considered as a way to explain anomalous light curves patterns of exoplanets, as the case of KIC 8462852 star.

Preparation for electron ring - plasma ring merging experiments in RECE-MERGE

International Nuclear Information System (INIS)

Taggart, D.; Sekiguchi, A.; Fleischmann, H.H.

1986-01-01

The formation of a mixed-CT using relativistic electron rings and gun-produced plasma rings by MERGE-ing them axially is simulated. This process is similar to the axial stacking of relativistic electron rings in RECE-Christa. The results of their first plasm production experiment are reported here. After study of the gun-produced plasma's properties is completed, the gun will be mounted at the downstream end of the vacuum tank and the source of relativistic electron rings will be at the upstream end. The two rings, formed at opposite ends of the tank, will be translated axially and merged

Device for monitoring electron-ion ring parameters

International Nuclear Information System (INIS)

Tyutyunnikov, S.I.; Shalyapin, V.N.

1982-01-01

The invention is classified as the method of collective ion acceleration. The device for electron-ion ring parameters monitoring is described. The invention is aimed at increasing functional possibilities of the device at the expense of the enchance in the number of the ring controlled parameters. The device comprises three similar plane mirrors installed over accelerating tube circumference and a mirror manufactured in the form of prism and located in the tube centre, as well as the system of synchrotron radiation recording and processing. Two plane mirrors are installed at an angle of 45 deg to the vertical axis. The angle of the third plane mirror 3 α and that of prismatic mirror 2 α to the vertical axis depend on geometric parameters of the ring and accelerating tube and they are determined by the expression α=arc sin R K /2(R T -L), where R K - ring radius, R T - accelerating tube radius, L - the height of segment, formed by the mirror and inner surface of the accelerating tube. The device suggested permits to determine longitudinal dimensions of the ring, its velocity and the number of electrons and ions in the ring

A numerical study of the quantum oscillations in multiple dangling rings

International Nuclear Information System (INIS)

Gu, B.Y.; Basu, C.

1994-12-01

We present the quantum mechanical calculations on magnetoconductance of the quantum waveguide topology containing multiply connected dangling mesoscopic rings with the transfer matrix approach. The profiles of the conductance as functions of the Fermi wave number of electrons and of the magnetic flux depend on the number of rings as also on the geometric configuration of the system. The conductance spectrum of this system for disordered lengths in the ring circumferences, dangling links, ballistic leads connecting consecutive dangling rings and disordered magnetic flux is examined in details. We find that there exist two kinds of mini-bands, one originating from the eigenstates of the rings, i.e. the intrinsic mini-bands, and the extra mini-bands. Some of these extra minibands are associated with the dangling links connecting the rings to the main quantum wire, while others are from the standing wave modes associated with the ballistic leads connecting adjacent dangling rings. These different kinds of mini-bands have completely different properties and responds differently to the geometric parameter fluctuations. Unlike the system of potential scatterers, this system of geometric scatterers shows complete band formations at all energies even for finite number of scatterers present. There is a preferential decay of the energy states, depending upon the type of disorder introduced. By controlling the geometric parameters, the conductance band structure of such a model can be artificially tailored and thus may guide the design of better mesoscopic switching devices. (author). 19 refs, 7 figs

Hubble again views Saturn's Rings Edge-on

Science.gov (United States)

1995-01-01

Saturn's magnificent ring system is seen tilted edge-on -- for the second time this year -- in this NASA Hubble Space Telescope picture taken on August 10, 1995, when the planet was 895 million miles (1,440 million kilometers) away. Hubble snapped the image as Earth sped back across Saturn's ring plane to the sunlit side of the rings. Last May 22, Earth dipped below the ring plane, giving observers a brief look at the backlit side of the rings. Ring-plane crossing events occur approximately every 15 years. Earthbound observers won't have as good a view until the year 2038. Several of Saturn's icy moons are visible as tiny starlike objects in or near the ring plane. They are from left to right, Enceladus, Tethys, Dione and Mimas. 'The Hubble data shows numerous faint satellites close to the bright rings, but it will take a couple of months to precisely identify them,' according to Steve Larson (University of Arizona). During the May ring plane crossing, Hubble detected two, and possibly four, new moons orbiting Saturn. These new observations also provide a better view of the faint E ring, 'to help determine the size of particles and whether they will pose a collision hazard to the Cassini spacecraft,' said Larson. The picture was taken with Hubble's Wide Field Planetary Camera 2 in wide field mode. This image is a composite view, where a long exposure of the faint rings has been combined with a shorter exposure of Saturn's disk to bring out more detail. When viewed edge-on, the rings are so dim they almost disappear because they are very thin -- probably less than a mile thick.The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science.This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/pubinfo/

Biocompatibility and Systemic Safety of a Novel Implantable Annuloplasty Ring for the Treatment of Mitral Regurgitation in a Minipig Model.

Science.gov (United States)

Ramot, Yuval; Rousselle, Serge D; Yellin, Nadav; Willenz, Udi; Sabag, Itai; Avner, Avi; Nyska, Abraham

2016-07-01

Prosthetic annuloplasty rings are a common treatment modality for mitral regurgitation, and recently, percutaneous implantation techniques have gained popularity due to their favorable safety profile. Although in common use, biocompatibility of annuloplasty rings has been reported only sparsely in the literature, and none of these reports used the percutaneous technique of implantation. We report on the biocompatibility and the systemic safety of a novel transcatheter mitral valve annuloplasty ring (AMEND™) in 6 minipigs. This device is composed of a nitinol tube surrounded by a braided polyethylene terephthalate fabric tube. The device produced no adverse inflammatory response, showing gradual integration between the metal ring and the fabric by normal host fibrocellular response, leading to complete neoendocardium coverage. There was no evidence for adverse reactions, rejection, or intolerance in the valvular structure. In 2 animals, hemopericardium resulted from the implantation procedure, leading to right-sided cardiac insufficiency with pulmonary edema and liver congestion. The findings reported herein can serve as a case study for the expected healing pathology reactions after implantation of transcatheter mitral valve annuloplasty rings. © The Author(s) 2016.

The naked toy model of a jumping ring

Science.gov (United States)

Donoso, Guillermo; Ladera, Celso L.

2014-01-01

We present a comprehensive analytical model of the well-known jumping ring—in fact an improved version of that system--as well as the experimental results that validate the model. Particular attention is paid to the magnetic driving force, whose explicit dependences upon the phase, amplitude and frequency of the exciting current we manage to separate experimentally and plot, so that it becomes evident how the magnetic force on the ring actually arises and evolves in time. We are able to measure not only the large Foucault currents that arise in the ring, but also the magnetic field generated by the ring itself in spite of the presence of the comparable magnetic field in which the ring moves.

Automatic local beam steering systems for NSLS x-ray storage ring: Design and implementation

International Nuclear Information System (INIS)

Singh, O.V.; Nawrocky, R.; Flannigan, J.

1991-01-01

Recently, two local automatic steering systems, controlled by microprocessors, have been installed and commissioned in the NSLS X- Ray storage ring. In each system, the position of the electron beam is stabilized at two locations by four independent servo systems. This paper describes three aspects of the local feedback program: design; commissioning; and limitation. The system design is explained by identifying major elements such as beam position detectors, signal processors, compensation amplifiers, ratio amplifiers, trim equalizers and microprocessor feedback controllers. System commissioning involves steps such as matching trim compensation, determination of local orbit bumps, measurement of open loop responses and design of servo circuits. Several limitations of performance are also discussed. 7 refs., 2 figs

System of Activities for the Development of the Appreciation Process of Folk Craft in Senior High Students

Directory of Open Access Journals (Sweden)

Yanulde Massano Galvez

2012-06-01

Full Text Available This work presents a system of activities for t he development of the appreciation process of folk craft in Senior High students. The Edad de Oro, by José Martí, is taken as a starting point, since this work considers authentic Cuban values stated by “The Teacher”. Consciousness about the Cuban cultural identity is fostered in the students by promoting local and traditional folk art.

The PEP electron-positron ring

International Nuclear Information System (INIS)

Rees, J.R.

1988-01-01

The first stage of the positron-electron-proton (PEP) colliding-beam system which has been under joint study by a Lawrence Berkeley Laboratory-Stanford Linear Accelerator Center team for the past two years, will be the electron-positron storage ring. The physics justification for the e + e/sup minus/ ring is summarized briefly and the proposed facility is described. The ring will have six arcs having gross radii of about 220 m and six interaction regions located at the centers of straight sections about 130 m long. The longitudinal distance left free for experimental apparatus at the intersection regions will be 20 m. The range of operating beam energies will be from 5 GeV to 15 GeV. The design luminosity at 15 GeV will be 10 32 cm/sup minus 2/s/sup minus 1/, and the luminosity will vary approximately as the square of the beam energy. Alternative methods under consideration for adjusting the beam cross-section are discussed. The designs of the storage ring subsystems and of the conventional facilities including the experimental halls at the interaction regions are described

Preliminary study on the adjonction of a cooling system and internal target ring to the GEPL project

International Nuclear Information System (INIS)

Potaux, D.

1983-01-01

Various heavy particle storage rings (LEAR, Indiana, Uppsala) are planned for operation with combined electron cooling system and internal ultra-thin targets. The advantage of adding a similar device to the IPN cyclotron project is discussed [fr

Plasma confinement in a magnetic field of the internal ring current

International Nuclear Information System (INIS)

Shafranov, Vitaly; Popovich, Paul; Samitov, Marat

2000-01-01

Plasma confinement in compact region surrounding an internal ring current is considered. As the limiting case of large aspect ratio system the cylindrical plasma is considered initially. Analysis of the cylindrical tubular plasma equilibrium and stability against the most dangerous flute (m=0) and kink (m=1) modes revealed the possibility of the MHD stable plasma confined by magnetic field of the internal rod current, with rather peaked plasma pressure and maximal local beta β(γ)=0.4. In case of the toroidal internal ring system an additional external magnetic field creates the boundary separatrix witch limits the plasma volume. The dependence of the plasma pressure profiles, marginally stable with respect to the flute modes, from the shape of the external plasma boundary (separatrix) in such kind closed toroidal systems is investigated. The internal ring system with circular poloidal magnetic mirror, where the ring supports could be placed, is proposed. (author)

Experimental Observation of Fermi-Pasta-Ulam Recurrence in a Nonlinear Feedback Ring System

Science.gov (United States)

Wu, Mingzhong; Patton, Carl E.

2007-01-01

Fermi-Pasta-Ulam recurrence through soliton dynamics has been realized. The experiment used a magnetic film strip-based active feedback ring. At some ring gain level, a wide spin wave pulse is self-generated in the ring. As the pulse circulates, it separates into two envelop solitons with different speeds. When the fast soliton catches up and collides with the slow soliton, the initial wide pulse is perfectly reconstructed. The repetition of this process leads to periodic recurrences of the initial pulse.

Groups, rings, modules

CERN Document Server

Auslander, Maurice

2014-01-01

This classic monograph is geared toward advanced undergraduates and graduate students. The treatment presupposes some familiarity with sets, groups, rings, and vector spaces. The four-part approach begins with examinations of sets and maps, monoids and groups, categories, and rings. The second part explores unique factorization domains, general module theory, semisimple rings and modules, and Artinian rings. Part three's topics include localization and tensor products, principal ideal domains, and applications of fundamental theorem. The fourth and final part covers algebraic field extensions

Nitrogen Fertilization for Optimizing the Quality and Yield of Shade Grown Cuban Cigar Tobacco: Required Nitrogen Amounts, Application Schedules, Adequate Leaf Nitrogen Levels, and Early Season Diagnostic Tests

Directory of Open Access Journals (Sweden)

Borges A

2014-12-01

Full Text Available Nitrogen (N fertilizers have a decisive influence on the yield and quality of tobacco. Yield, percentage of plant N, wrapper leaf quality, and nicotine content are all important quality characteristics in tobacco growing. This work is an attempt to provide a tool for optimizing mineral N nutrition for Cuban cigar tobacco, using a strategy that links N supply with leaf N concentration and wrapper yield. Similar approaches developed worldwide have mainly involved Virginia and Burley tobacco types but not Cuban cigar tobacco. The objective of the current work is to identify the effects of fertilizer N levels and timing of application on each of the mentioned quality factors for shade grown Cuban cigar tobacco. Another purpose is to explore the usefulness of a quick method of assessing the N status of plants based on measuring leaf transmission at two different wavelengths (650 and 940 nm. The experiments were done in the main tobacco growing area of Cuba (Vueltabajo. In each experiment, nine separate treatments were used covering different levels and times of fertilizer N application. The same experiment was carried out in three different years (2005-2006, 2006-2007, 2007-2008 but as the results were similar only one set of data is described (2006-2007. The patterns of response to N fertilizer of all four quality measurements, including yield and wrapper leaf quality, were similar in the different replications of the experiments. The optimal fertilizer level was 140-190 kg N/ha (40% applied on days 8-10 after transplanting and 60% on days 18-20 after transplanting. The optimal N concentration of leaves taken at the central foliar level of the middle stalk position was 4.3-4.7% at harvest time. Leaf transmission measurements by means of the SPAD-502 Chlorophyll Meter in the early stages of growth were correlated with leaf chlorophyll and N concentration and provide an excellent guide for predicting Cuban cigar tobacco wrapper leaf yield.

Conceptual design of a linac-stretcher ring to obtain a 2-GeV continuous electron beam

International Nuclear Information System (INIS)

Cho, Y.; Holt, R.J.; Jackson, H.E.; Khoe, T.K.; Mavrogenes, G.S.

1981-01-01

In order to obtain a high duty factor, > 100 μA 2-GeV electron beam, we have designed a linac-stretcher ring system. The system is an attractive option because it draws heavily on the existing accelerator technology. The linac-stretcher ring consists of a 2-GeV SLAC-type pulsed linac which injects into a storage ring. In between linac pulses, the stored electron beam is to extract resonantly. This design differs from those discussed recently in several important respects. The storage ring includes an RF system whose purpose is to control the beam orbit and rate of extraction from the ring. With an RF system in the ring, the injection scheme consists of a few turns of synchronous transfers of beam between the linac and storage ring

The Rotating Ring-Ring Electrode. Theory and Experiment

NARCIS (Netherlands)

Kuiken, H.K.; Bakkers, E.P.A.M.; Ligthart, H.; Kelly, J.J.

2000-01-01

A model is presented for the rotating ring-ring electrode. Although the electrode is defined by four characteristic lengths, it is shown that the collection efficiency depends on only two dimensionless parameters. A simple relationship between these and the corresponding parameters for the rotating

Optical Properties of a Quantum Dot-Ring System Grown Using Droplet Epitaxy.

Science.gov (United States)

Linares-García, Gabriel; Meza-Montes, Lilia; Stinaff, Eric; Alsolamy, S M; Ware, M E; Mazur, Y I; Wang, Z M; Lee, Jihoon; Salamo, G J

2016-12-01

Electronic and optical properties of InAs/GaAs nanostructures grown by the droplet epitaxy method are studied. Carrier states were determined by k · p theory including effects of strain and In gradient concentration for a model geometry. Wavefunctions are highly localized in the dots. Coulomb and exchange interactions are studied and we found the system is in the strong confinement regime. Microphotoluminescence spectra and lifetimes were calculated and compared with measurements performed on a set of quantum rings in a single sample. Some features of spectra are in good agreement.

The amplitude and phase control of the ALS Storage Ring RF System

International Nuclear Information System (INIS)

Lo, C.C.; Taylor, B.; Baptiste, K.

1995-03-01

A 500MHz, 300KW Klystron power amplifier provides RF power to the ALS Storage Ring. In order to accommodate the amplitude and phase changes during beam stacking and decay, which demand continuously varying power levels from the Klystron, four loops are used to keep the system operating properly, with two of those loops dedicated to keeping the two cavity tuners on tune. Description of the control loops and their performance data will be given. Using the modulation anode of the Klystron in the amplitude loop will be discussed

Stable optical soliton in the ring-cavity fiber system with carbon nanotube as saturable absorber

Science.gov (United States)

Li, Bang-Qing; Ma, Yu-Lan; Yang, Tie-Mei

2018-01-01