Sample records for cubane ring system

  1. Improving Nonspecific Binding and Solubility: Bicycloalkyl Groups and Cubanes as para-Phenyl Bioisosteres.

    PubMed

    Auberson, Yves P; Brocklehurst, Cara; Furegati, Markus; Fessard, Thomas C; Koch, Guido; Decker, Andrea; La Vecchia, Luigi; Briard, Emmanuelle

    2017-04-20

    Bicycloalkyl groups have been previously described as phenyl group bioisosteres. This article describes the synthesis of new building blocks allowing their introduction into complex molecules, and explores their use as a means to modify the physicochemical properties of drug candidates and improve the quality of imaging agents. In particular, the replacement of an aromatic ring with a bicyclo[1.1.1]pentane-1,3-diyl (BCP) group improves aqueous solubility by at least 50-fold, and markedly decreases nonspecific binding (NSB) as measured by CHI(IAM), the chromatographic hydrophobicity index on immobilized artificial membranes. Structural variations with the bicyclo[2.2.2]octane-1,4-diyl group led to more lipophilic molecules and did not show the same benefits regarding NSB or solubility, whereas substitutions with cubane-1,4-diyl showed improvements for both parameters. These results confirm the potential advantages of both BCP and cubane motifs as bioisosteric replacements for optimizing para-phenyl-substituted molecules. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. The Cuban Vocational Education and Training System and Its Current Changes

    ERIC Educational Resources Information Center

    Wolf, Stefan; Penton, Felipe A. Hernandez; Marin, Anna Lidia Beltran; Romero, Osvaldo

    2011-01-01

    The main purpose of the article is to inform about the Cuban Vocational Education and Training System. Based on the analyse of different studies, on expert interviews and on field experiences the authors give a clear overview of the Cuban VET-System. This description is embedded in the presentation of the general education system in Cuba and in a…

  3. The Dynamics of Cuba Anticyclones (CubANs) and Interaction With the Loop Current/Florida Current System

    NASA Astrophysics Data System (ADS)

    Kourafalou, Vassiliki; Androulidakis, Yannis; Le Hénaff, Matthieu; Kang, HeeSook

    2017-10-01

    Mesoscale anticyclonic eddies along the northern Cuban coast (CubANs) have been identified in the Straits of Florida, associated with the northward shift of the Florida Current (FC) and the anticyclonic curvature of the Loop Current (LC) at the western entrance of the Straits. The dynamics of CubAN eddies and their interaction with the LC/FC system are described for the first time using satellite, drifter and buoy data, and a high-resolution model. It is shown that the evolution of CubANs to the south of the FC front complements the evolution of cyclonic eddies to the north of the FC, advancing previous studies on synergy between FC meandering and eddy activity. Two types of CubAN eddies are characterized: (a) a main anticyclonic cell (type "A") within the core of the LC during retracted phase conditions, associated with the process of LC Eddy (LCE) shedding from an extended LC, and (b) an individual, distinct anticyclonic eddy that is released from the main LC core and is advected eastward, along the northern Cuban coast (type "B"). There are also mixed cases, when the process of LCE shedding has started, so a type "A" CubAN is being formed, in the presence of one or more eastward progressing type "B" eddies. CubAN evolution is associated with an increased mixed layer and weaker stratification of the upper ocean along the eddy's track. The cyclonic activity along the Cuban coast and wind-induced upwelling events also contribute to the evolution and fate of the CubAN eddies.

  4. The Cuban health care system and factors currently undermining it.

    PubMed

    Nayeri, K

    1995-08-01

    This paper explores the dynamics of health and health care in Cuba during a period of severe crisis by placing it within its economic, social, and political context using a comparative historical approach. It outlines Cuban achievements in health care as a consequence of the socialist transformations since 1959, noting the full commitment by the Cuban state, the planned economy, mass participation, and a self-critical, working class perspective as crucial factors. The roles of two external factors, the U.S. economic embargo and the Council of Mutual Economic Cooperation (CMEA), are explored in shaping the Cuban society and economy, including its health care system. It is argued that the former has hindered health efforts in Cuba. The role of the latter is more complex. While the CMEA was an important source for economic growth, Cuban relations with the Soviet bloc had a damaging effect on the development of socialism in Cuba. The adoption of the Soviet model of economic development fostered bureaucracy and demoralization of Cuban workers. As such, it contributed to two internal factors that have undermined further social progress including in health care: low productivity of labor and the growth of bureaucracy. While the health care system is still consistently supported by public policy and its structure is sound, economic crisis undermines its material and moral foundations and threatens its achievements. The future of the current Cuban health care system is intertwined with the potentials for its socialist development.

  5. A case analysis of INFOMED: the Cuban national health care telecommunications network and portal.

    PubMed

    Séror, Ann C

    2006-01-27

    The Internet and telecommunications technologies contribute to national health care system infrastructures and extend global health care services markets. The Cuban national health care system offers a model to show how a national information portal can contribute to system integration, including research, education, and service delivery as well as international trade in products and services. The objectives of this paper are (1) to present the context of the Cuban national health care system since the revolution in 1959, (2) to identify virtual institutional infrastructures of the system associated with the Cuban National Health Care Telecommunications Network and Portal (INFOMED), and (3) to show how they contribute to Cuban trade in international health care service markets. Qualitative case research methods were used to identify the integrated virtual infrastructure of INFOMED and to show how it reflects socialist ideology. Virtual institutional infrastructures include electronic medical and information services and the structure of national networks linking such services. Analysis of INFOMED infrastructures shows integration of health care information, research, and education as well as the interface between Cuban national information networks and the global Internet. System control mechanisms include horizontal integration and coordination through virtual institutions linked through INFOMED, and vertical control through the Ministry of Public Health and the government hierarchy. Telecommunications technology serves as a foundation for a dual market structure differentiating domestic services from international trade. INFOMED is a model of interest for integrating health care information, research, education, and services. The virtual infrastructures linked through INFOMED support the diffusion of Cuban health care products and services in global markets. Transferability of this model is contingent upon ideology and interpretation of values such as individual intellectual property and confidentiality of individual health information. Future research should focus on examination of these issues and their consequences for global markets in health care.

  6. A Case Analysis of INFOMED: The Cuban National Health Care Telecommunications Network and Portal

    PubMed Central

    2006-01-01

    Background The Internet and telecommunications technologies contribute to national health care system infrastructures and extend global health care services markets. The Cuban national health care system offers a model to show how a national information portal can contribute to system integration, including research, education, and service delivery as well as international trade in products and services. Objective The objectives of this paper are (1) to present the context of the Cuban national health care system since the revolution in 1959, (2) to identify virtual institutional infrastructures of the system associated with the Cuban National Health Care Telecommunications Network and Portal (INFOMED), and (3) to show how they contribute to Cuban trade in international health care service markets. Methods Qualitative case research methods were used to identify the integrated virtual infrastructure of INFOMED and to show how it reflects socialist ideology. Virtual institutional infrastructures include electronic medical and information services and the structure of national networks linking such services. Results Analysis of INFOMED infrastructures shows integration of health care information, research, and education as well as the interface between Cuban national information networks and the global Internet. System control mechanisms include horizontal integration and coordination through virtual institutions linked through INFOMED, and vertical control through the Ministry of Public Health and the government hierarchy. Telecommunications technology serves as a foundation for a dual market structure differentiating domestic services from international trade. Conclusions INFOMED is a model of interest for integrating health care information, research, education, and services. The virtual infrastructures linked through INFOMED support the diffusion of Cuban health care products and services in global markets. Transferability of this model is contingent upon ideology and interpretation of values such as individual intellectual property and confidentiality of individual health information. Future research should focus on examination of these issues and their consequences for global markets in health care. PMID:16585025

  7. Cuban Calisto (Lepidoptera, Nymphalidae, Satyrinae), a review based on morphological and DNA data

    PubMed Central

    Aguila, Rayner Núñez; Plasencia, Edelquis Oliva; Maravi, Pavel F. Matos; Wahlberg, Niklas

    2012-01-01

    Abstract The Cuban species of Calisto are reviewed based on the morphology of adult and immature stages, as well as DNA sequences of six genes (COI, EF1α, wingless, GAPDH, RpS5, CAD). A new species, Calisto occulta sp. n., is described from the northeastern Cuban mountains. Calisto smintheus Bates, 1935 and Calisto bruneri, Michener 1949 are revised and revalidated. A new status, the species level, is proposed for Calisto brochei, Torre 1973, Calisto muripetens, Bates 1939 and Calisto bradleyi, Munroe 1950. The immature stages of Calisto smintheus, Calisto brochei,and Calisto occulta are described for the first time, and those of Calisto herophile, Hübner 1823 are redescribed. Useful morphological characters for adults are the shape and conspicuousness of androconial patch, the number and relative size of white dots on underside of hindwing, the shape of aedeagus, the shape of digitiform projection of genitalia valve, the shape and relative size of tegumen and uncus, the relative size of female genitalia, the height of sterigmal ring dorsal crown of the latter, and the relative size of corpus bursae and ductus bursae. For the immature stages, the most important characters are the color pattern of head capsule, the number and width of longitudinal lines of body, in the larvae; and the color pattern and the absence or presence of dorsal ridges on the abdomen of pupae. The phylogenetic relationships between the Cuban Calisto species are quite robust and well-supported; however, conflict between mitochondrial and nuclear datasets was detected in Calisto brochei, Calisto muripetens and to a lesser degree in Calisto bradleyi. PMID:22328857

  8. Cuban Libraries: 30 Years after the Revolution.

    ERIC Educational Resources Information Center

    Chepesiuk, Ron

    1990-01-01

    Discussion of the Cuban library system includes comments from interviews with leading librarians in that country. Effects of the Castro regime and the U.S. embargo on Cuba and its libraries are considered. (MES)

  9. [Change and revolution: the rise of the National Health System in Cuba, 1959-1970].

    PubMed

    Chaple, Enrique Beldarraín

    2005-01-01

    This article studies the impact on the Cuban public health system of the political, economical and social changes that occurred after the 1959 Revolution, and the main transformations that occurred in the Cuban public health system during the 1960s, such as the creation of a new public health ministry, the nationalization of the pharmaceutical industry, the massive emigration of health professionals, a reform of medical studies, the creation of a Medical Rural Service, the incorporation of socialist principles in public health and the development of primary health care. As this article intends to demonstrate, these measures guided Cuban public health reform towards the construction of a state monopolized National Health System in 1970.

  10. [The health system of Cuba].

    PubMed

    Domínguez-Alonso, Emma; Zacea, Eduardo

    2011-01-01

    This paper describes the health conditions in Cuba and the general characteristics of the Cuban health system, including its structure and coverage, its financial sources, its health expenditure, its physical, material and human resources, and its stewardship functions. It also discusses the increasing importance of its research institutions and the role played by its users in the operation and evaluation of the system. Salient among the social actors involved in the health sector are the Cuban Women Federation and the Committees for the Defense of the Revolution. The paper concludes with the discussion of the most recent innovations implemented in the Cuban health system, including the cardiology networks, the Miracle Mission (Misión Milagro) and the Battle of Ideas (Batalla de Ideas).

  11. First principles study of electronic structure for cubane-like and ring-shaped structures of M{sub 4}O{sub 4}, M{sub 4}S{sub 4} clusters (M = Mn, Fe, Co, Ni, Cu)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Datta, Soumendu, E-mail: soumendu@bose.res.in; Rahaman, Badiur

    2015-11-15

    Spin-polarized DFT has been used to perform a comparative study of the geometric structures and electronic properties for isolated M{sub 4}X{sub 4} nano clusters between their two stable isomers - a planar rhombus-like 2D structure and a cubane-like 3D structure with M = Mn, Fe, Co, Ni, Cu ; X = O, S. These two structural patterns of the M{sub 4}X{sub 4} clusters are commonly found as building blocks in several poly-nuclear transition metal complexes in inorganic chemistry. The effects of the van der Waals corrections to the physical properties have been considered in the electronic structure calculations employing themore » empirical Grimme’s correction (DFT+D2). We report here an interesting trend in their relative structural stability - the isolated M{sub 4}O{sub 4} clusters prefer to stabilize more in the planar structure, while the cubane-like 3D structure is more favorable for most of the isolated M{sub 4}S{sub 4} clusters than their planar 2D counterparts. Our study reveals that this contrasting trend in the relative structural stability is expected to be driven by an interesting interplay between the s-d and p-d hybridization effects of the constituents’ valence electrons.« less

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

    PubMed

    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.

  13. In situ characterization of cofacial Co(IV) centers in Co 4O 4 cubane: Modeling the high-valent active site in oxygen-evolving catalysts

    DOE PAGES

    Brodsky, Casey N.; Hadt, Ryan G.; Hayes, Dugan; ...

    2017-03-27

    The Co 4O 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 measurementsmore » 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 4O 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.« less

  14. Cuban Mass Media: Organization, Control and Functions. Journalism Monographs Number Seventy-Eight.

    ERIC Educational Resources Information Center

    Nichols, John Spicer

    The mass media as interdependent parts of a larger social system both control and are controlled by other subsystems. The various combinations of control, in turn, determine the functions the media system will serve. In the 1960's, the Cuban mass media underwent frequent change that reflected the volatility of the revolutionary process. Today,…

  15. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brodsky, Casey N.; Hadt, Ryan G.; Hayes, Dugan

    The Co 4O 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 measurementsmore » 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 4O 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.« less

  16. Lattice dynamics of a rotor-stator molecular crystal: Fullerene-cubane C60ṡC8H8

    NASA Astrophysics Data System (ADS)

    Bousige, Colin; Rols, Stéphane; Cambedouzou, Julien; Verberck, Bart; Pekker, Sándor; Kováts, Éva; Durkó, Gábor; Jalsovsky, István; Pellegrini, Éric; Launois, Pascale

    2010-11-01

    The dynamics of fullerene-cubane (C60ṡC8H8) cocrystal is studied combining experimental [x-ray diffuse scattering, quasielastic and inelastic neutron scattering (INS)] and simulation (molecular dynamics) investigations. Neutron scattering gives direct evidence of the free rotation of fullerenes and of the libration of cubanes in the high-temperature phase, validating the “rotor-stator” description of this molecular system. X-ray diffuse scattering shows that orientational disorder survives the order/disorder transition in the low-temperature phase, although the loss of fullerene isotropic rotational diffusion is featured by the appearance of a 2.2 meV mode in the INS spectra. The coupling between INS and simulations allows identifying a degeneracy lift of the cubane librations in the low temperature phase, which is used as a tool for probing the environment of cubane in this phase and for getting further insights into the phase transition mechanism.

  17. Theoretical Studies of Some HEDM Species: Cyclic O4, Cyclic O3 and Cubane

    NASA Technical Reports Server (NTRS)

    Walch, Stephen P.; Langhoff, Steve R. (Technical Monitor)

    1996-01-01

    Calculations have been carried out for the HEDM species (cyclic O4, cyclic O3, and cubane) using CASSCF/derivative and CASSCF/ICCI methods. Cyclic O4 is of interest both as a potential HEDM species and because of its possible role in the ozone deficit problem in atmospheric chemistry. We have studied the pathway for decomposition from the D(2d) minimum and also have found the approximate location of the singlet triplet crossing. The barrier to decomposition is found to be about 9 kcal/mol and is not limited by the singlet triplet crossing. For cyclic O3 we have focused on the crossings between the lowest five surfaces (X(1)A(1), s(1)A(1), (1)A(2), (1)B(1), and (1)B(2)) to provide some insight into ways to form cyclic O3 photochemically. The crossing region between the X(1)A(1) and 2(1)A(1) surfaces is in agreement with the work of Xantheas et al. The calculations show that vertical excitation from the ground state to the (1)A(2) state leads to a crossing with the (1)A(1) manifold near the crossing region of the X(1)A(1) and 2(1)A(1) surfaces. We have studied the decomposition pathways for cubane to benzene plus acetylene and to cyclooctatetraene. We have also studied the ground and excited states for the photochemical ring closure step. The state which closes to cubane can be described as a double triplet pi to pi* excitation with respect to the ground state. Thus, this state has only a small oscillator strength with respect to the ground state. However, there is a singlet pi to pi* state at nearly the same energy and excitation to this state followed by intersystem crossing could lead to the triplet pi to pi* state.

  18. A Look at Cuban Schools: What Is Cuba Doing Right?

    ERIC Educational Resources Information Center

    Hunt, Barbara C.

    2003-01-01

    A retired elementary school principal, who first visited Cuba as an exchange student, returns 46 years later as an international consultant and finds that the Cubans have made health care and education the top priorities of their society with strong principals and a solid system of supervision and evaluation. (Author/MLF)

  19. South-South Collaboration: Cuban Teachers in Jamaica and Namibia

    ERIC Educational Resources Information Center

    Hickling-Hudson, Anne

    2004-01-01

    Cuba has concentrated more than most developing countries on building a sound educational system, and as a result, it has been able to collaborate with other countries in their efforts to improve educational planning and practice. Based on recent research in the field, this paper examines the work of Cuban teachers in schools and sports programmes…

  20. Parental Involvement and the Academic Achievement and Social Functioning of Cuban School Children

    ERIC Educational Resources Information Center

    Alvarez-Valdivia, Ibis M.; Chavez, Kenia Lorenzo; Schneider, Barry H.; Roberts, Jesse S.; Becalli-Puerta, Laura E.; Perez-Lujan, Dalgys; Sanz-Martinez, Yuri Arsenio

    2013-01-01

    The goal of the current study was to investigate whether parental involvement is an important predictor of student outcomes within the Cuban school system, where extensive support for pupils' progress and adjustment are available from the peer group, community, and family. The participants were 188 children in Grades 2 and 3 from four localities…

  1. Stories of Cuban-Americans Living and Learning Bilingually

    ERIC Educational Resources Information Center

    Perez, Natasha

    2017-01-01

    This study explores the interplay of bilingualism, identity, literacy and culture for CubanAmerican students in the Cuban diaspora. I contextualize their experiences within the social, historical, and political background of Cuban immigration, situating their stories within the conflicting narratives of Cuban-American imagination in the U.S., to…

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

    PubMed Central

    2012-01-01

    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 return from Cuba, some PICs may face substantial rises in salary expenditure which could significantly strain already stretched government budgets. Finally, the Cuban engagement in the Pacific has implications for the wider geo-political and health sector support environment as the relatively few major bilateral donors, notably Australia (through AusAID) and New Zealand (through NZAID), and multilaterals such as the World Bank will need to accommodate an additional player with whom existing links are limited. PMID:22558940

  3. Magnetic Resonance Project 35-26-7: A Cuban Case of Engineering Physics and Biophysics

    NASA Astrophysics Data System (ADS)

    Cabal Mirabal, Carlos A.

    The Magnetic Resonance Project 35-26-7 started in December 1987, commissioned by the [then] Cuban Prime Minister, Fidel Castro, who—concerned about introducing technological advancement into the Cuban health [system]—had for some months taken an interest in the possibility of building magnetic resonance imaging (MRI) equipment for medical diagnosis in Cuba (Zito M, Argüelles MM et al, Y sin embargo-: ciencia: hablan 30 investigadores cubanos. Editoria April, Habana, pp 56-66, 1999; Cabal, Biofísica Médica. In: Fidel Castro Dìas-Balart (eds) Cuba. Amanecer del Tercer Milenio. Ciencia, Sociedad y Tecnología: Biofísica Médica. Debate Editorial, Madrid, pp 31-48, 2002). Many of the companies producing MRI equipment were unable to deliver this technology to Cuba due to the bloqueo, the United States embargo against Cuba. Those who were later to advance the project's progress in scientific technology initially regarded the implementation of such a project in a developing country as unfeasible due to its complexity. But Fidel's belief and confidence and in turn the Cuban scientists' commitment to him and to Cuban science proved to be an undeniable factors for its success.

  4. Lifestyle Risk Factors and Cardiovascular Disease in Cubans and Cuban Americans

    PubMed Central

    Burroughs Peña, Melissa S.; Patel, Dhaval; Rodríguez Leyva, Delfin; Khan, Bobby V.; Sperling, Laurence

    2012-01-01

    Cardiovascular disease is the leading cause of mortality in Cuba. Lifestyle risk factors for coronary heart disease (CHD) in Cubans have not been compared to risk factors in Cuban Americans. Articles spanning the last 20 years were reviewed. The data on Cuban Americans are largely based on the Hispanic Health and Nutrition Examination Survey (HHANES), 1982–1984, while more recent data on epidemiological trends in Cuba are available. The prevalence of obesity and type 2 diabetes mellitus remains greater in Cuban Americans than in Cubans. However, dietary preferences, low physical activity, and tobacco use are contributing to the rising rates of obesity, type 2 diabetes mellitus, and CHD in Cuba, putting Cubans at increased cardiovascular risk. Comprehensive national strategies for cardiovascular prevention that address these modifiable lifestyle risk factors are necessary to address the increasing threat to public health in Cuba. PMID:22203917

  5. Recovery of native treefrogs after removal of nonindigenous Cuban Treefrogs, Osteopilus septentrionalis

    USGS Publications Warehouse

    Rice, K.G.; Waddle, J.H.; Miller, M.W.; Crockett, M.E.; Mazzotti, F.J.; Percival, H.F.

    2011-01-01

    Florida is home to several introduced animal species, especially in the southern portion of the state. Most introduced species are restricted to the urban and suburban areas along the coasts, but some species, like the Cuban Treefrog (Osteopilus septentrionalis), are locally abundant in natural protected areas. Although Cuban Treefrogs are known predators of native treefrog species as both adults and larvae, no study has demonstrated a negative effect of Cuban Treefrogs on native treefrog survival, abundance, or occupancy rate. We monitored survival, capture probability, abundance, and proportion of sites occupied by Cuban Treefrogs and two native species, Green Treefrogs (Hyla cinerea) and Squirrel Treefrogs (Hyla squirella), at four sites in Everglades National Park in southern Florida with the use of capture–mark–recapture techniques. After at least 5 mo of monitoring all species at each site we began removing every Cuban Treefrog captured. We continued to estimate survival, abundance, and occupancy rates of native treefrogs for 1 yr after the commencement of Cuban Treefrog removal. Mark–recapture models that included the effect of Cuban Treefrog removal on native treefrog survival did not have considerable Akaike's Information Criterion (AIC) weight, although capture rates of native species were generally very low prior to Cuban Treefrog removal. Estimated abundance of native treefrogs did increase after commencement of Cuban Treefrog removal, but also varied with the season of the year. The best models of native treefrog occupancy included a Cuban Treefrog removal effect at sites with high initial densities of Cuban Treefrogs. This study demonstrates that an introduced predator can have population-level effects on similar native species.

  6. Russian-Cuban Colocation Station for Radio Astronomical Observation and Monitoring of Near-Earth Space

    NASA Astrophysics Data System (ADS)

    Ivanov, D. V.; Uratsuka, M.-R.; Ipatov, A. V.; Marshalov, D. A.; Shuygina, N. V.; Vasilyev, M. V.; Gayazov, I. S.; Ilyin, G. N.; Bondarenko, Yu. S.; Melnikov, A. E.; Suvorkin, V. V.

    2018-04-01

    The article presents the main possibilities of using the projected Russian-Cuban geodynamic colocation station on the basis of the Institute of Geophysics and Astronomy of the Ministry of Science, Technology and the Environment of the Republic of Cuba to carry out radio observations and monitoring the near-Earth space. Potential capabilities of the station are considered for providing various observational programs: astrophysical observations; observations by space geodesy methods using radio very long baselines interferometers, global navigation satellite systems, laser rangers, and various Doppler systems, as well as monitoring of artificial and natural bodies in the near-Earth and deep space, including the ranging of asteroids approaching the Earth. The results of modeling the observations on the planned station are compared with that obtained on the existing geodynamic stations. The efficiency of the projected Russian-Cuban station for solving astronomical tasks is considered.

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

    USGS Publications Warehouse

    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.

  8. Selenium as a Structural Surrogate of Sulfur: Template-Assisted Assembly of Five Types of Tungsten-Iron-Sulfur/Selenium Clusters and the Structural Fate of Chalcogenide Reactants

    PubMed Central

    Zheng, Bo; Chen, Xu-Dong; Zheng, Shao-Liang; Holm, R. H.

    2012-01-01

    Syntheses of five types of tungsten-iron-sulfur/selenium clusters–incomplete cubanes, single cubanes, edge-bridged double cubanes (EBDCs), PN-type clusters, and double-cuboidal clusters–have been devised based on the concept of template-assisted assembly. The template reactant is six-coordinate [(Tp*)WVIS3]1−, which in the assembly systems organizes FeII,III and sulfide/selenide into cuboidal [(Tp*)WFe2S3] or cubane [(Tp*)WFe3S3Q] units. With appropriate terminal iron ligation, these units are capable of independent existence or may be transformed into higher nuclearity species. Selenide is used as a surrogate for sulfide in cluster assembly in order to determine by X-ray structures the position occupied by an external chalcogenide nucleophile or an internal chalcogenide atom in product clusters. Specific incorporation of selenide is demonstrated by formation of [WFe3S3Se]2+,3+ cubane cores. Reductive dimerization of the cubane leads to the EBDC core [W2Fe6S6Se2]2+ containing μ4-Se sites. Reaction of these species with HSe− affords the PN-type cores [W2Fe6S6Se3]1+ in which selenide occupies μ6-Se and μ2-Se sites. Reaction of [(Tp*)WS3]1−, FeCl2, and Na2Se results in the double cuboidal [W2Fe4S6Se3]2+,0 core with μ2-Se and μ4-Se bridges. It is highly probable that in analogous sulfide-only assembly systems, external and internal sulfide reactants occupy corresponding positions in cluster products. The results further demonstrate the viability of template-assisted cluster synthesis inasmuch as the reduced (Tp*)WS3 unit is present in all clusters. Structures, zero-field Mössbauer data, and redox potentials are presented for all cluster types. (Tp* = tris(pyrazolyl)hydroborate(1−)) PMID:22424175

  9. Cubans abroad: a gendered case study on international migrations.

    PubMed

    Núñez-Sarmiento, Marta

    2010-01-01

    Cubans who have migrated since the 1990s after living for two decades or more in their country of origin left with an embedded gender ideology that they acquired in a society where gender relations were undergoing radical transformations. As a result, Cuban feminization of migrations has its peculiarities. In this context, there are three issues to consider: explaining how gender relations attained in Cuba, as part of the overall attitudes gained since childhood, influenced Cuban migrants who have left the island permanently since 1990, introduced uniqueness in their migration processes, and made up a different feminization of migration; identifying the features of Cuban social structure that shaped the gender ideology of Cuban migrants; and producing new knowledge about Cuban international migration processes by using a gender perspective and by analyzing the gender relations prevailing in the years before the crisis of the 1990s, as well as since the beginning of the twenty-first century. The first part of this article focuses on gender distinctiveness of recent Cuban migrants, and the second summarizes some traits of the Cuban social structure—mainly referred to female employment—that could explain the gender training of the migrants.

  10. Cuban Studies Newsletter.

    ERIC Educational Resources Information Center

    Pittsburgh Univ., PA. University Center for International Studies.

    This is the first issue of the Cuban Studies Newsletter, a biannual publication designed to provide comprehensive and timely communication among those interested in Cuban Studies. The purpose of the newsletter stated in a recommendation by the International Conference on Cuban Bibliography and Acquisitions, April, 1970, is to promote the scholarly…

  11. Impressions of the Republic of Cuba. A Report by a Delegation of the American Association of State Colleges and Universities to the Republic of Cuba, December 2-10, 1978.

    ERIC Educational Resources Information Center

    Schwartz, Carol R., Ed.

    Impressions of the Republic of Cuba are presented based on a visit to Cuba in 1978 by a delegation of the American Association of State Colleges and Universities. The following topics are discussed: the Cuban educational system, Cuban postsecondary education, goals of postsecondary education, elementary education, vocational and technical…

  12. The Curious Case of Cuba

    PubMed Central

    Reed, Gail A.

    2012-01-01

    As health professionals in the United States consider how to focus health care and coverage to ensure better, more equitable patient and population health outcomes, the experience of Cuba’s National Health System over the last 5 decades may provide useful insights. Although mutual awareness has been limited by long-term political hostilities between the United States and Cuban governments, the history and details of the Cuban health system indicate that their health system merits attention as an example of a national integrated approach resulting in improved health status. More extensive analysis of the principles, practices, and outcomes in Cuba is warranted to inform health system transformation in the United States, despite differences in political-social systems and available resources. PMID:22698011

  13. Diabetes-related mortality among Mexican Americans, Puerto Ricans, and Cuban Americans in the United States.

    PubMed

    Smith, Chrystal A S; Barnett, Elizabeth

    2005-12-01

    Hispanics are the most rapidly growing minority group in the United States, and Mexican Americans, Puerto Ricans and Cuban Americans are the three largest Hispanic subgroups. Among Hispanics, type 2 diabetes is the fifth leading cause of death. This paper examines diabetes-related mortality in Mexican Americans, Puerto Ricans, and Cuban Americans over 35 years of age in the United States during 1996 and 1997. Using data from the National Vital Statistics System and the 1990 and 2000 censuses, we calculated age-adjusted and age-specific diabetes-related death rates for Mexican Americans, Puerto Ricans, and Cuban Americans over 35 years of age. Diabetes-related deaths were determined to be any death for which diabetes was coded as either the underlying or contributing cause of death. The diabetes-related mortality rate for Mexican Americans (251 per 100,000) and Puerto Ricans (204 deaths per 100,000) was twice as high as the diabetes-related mortality rate for Cuban Americans (101 deaths per 100,000). Cuban American decedents had the highest proportion of deaths with diabetes coded as the underlying cause of death (44%). After diabetes, heart disease (31%) followed by cancer (8%) and stroke (6%) were the most frequent primary underlying causes of diabetes-related deaths in all three ethnic groups. Our analyses of these data demonstrate that diabetes-related mortality differed among Mexican Americans, Puerto Ricans and Cuban Americans more than 35 years of age in the United States in 1996 and 1997. Socioeconomic factors such as low educational attainment and low income may be factors that contributed to the disparities in these mortality rates for different subgroups. Further research is needed to update these findings and to investigate explanatory risk factors. Diversity among Hispanic subgroups has persisted in recent years and should be considered when health policies and services targeted at these populations are developed.

  14. 31 CFR 515.574 - Support for the Cuban People.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Support for the Cuban People. 515.574..., Authorizations, and Statements of Licensing Policy § 515.574 Support for the Cuban People. (a) Specific licenses....560(c) and other transactions that are intended to provide support for the Cuban people including, but...

  15. 45 CFR 401.12 - Cuban and Haitian entrant cash and medical assistance.

    Code of Federal Regulations, 2010 CFR

    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...

  16. 31 CFR 515.574 - Support for the Cuban People.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Support for the Cuban People. 515.574..., Authorizations, and Statements of Licensing Policy § 515.574 Support for the Cuban People. (a) Specific licenses....560(c) and other transactions that are intended to provide support for the Cuban people including, but...

  17. 31 CFR 515.574 - Support for the Cuban People.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Support for the Cuban People. 515.574..., Authorizations, and Statements of Licensing Policy § 515.574 Support for the Cuban People. (a) Specific licenses....560(c) and other transactions that are intended to provide support for the Cuban people including, but...

  18. 31 CFR 515.574 - Support for the Cuban People.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Support for the Cuban People. 515.574..., Authorizations, and Statements of Licensing Policy § 515.574 Support for the Cuban People. (a) Specific licenses....560(c) and other transactions that are intended to provide support for the Cuban people including, but...

  19. 31 CFR 515.574 - Support for the Cuban People.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Support for the Cuban People. 515.574..., Authorizations, and Statements of Licensing Policy § 515.574 Support for the Cuban People. (a) Specific licenses....560(c) and other transactions that are intended to provide support for the Cuban people including, but...

  20. Evaluation and Identification of Policy Issues in the Cuban Community.

    ERIC Educational Resources Information Center

    Diaz, Guarione M., Ed.

    The research described in this report identifies the major health, education, and welfare-related needs of Cuban Americans as defined by directors of Cuban community service organizations and Cuban beneficiary populations in the selected urban areas of Miami/Dade County, Union City/West New York, New York City, Los Angeles, and Chicago. Data from…

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

    PubMed

    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.

  2. The Cubans. Their History and Culture. CAL Refugee Fact Sheet Series No. 12.

    ERIC Educational Resources Information Center

    Robson, Barbara

    This fact sheet is designed to give those working with newly arrived Cubans in the United States a brief refresher on Cuban geography and history, especially the history of Cuba's relations with the United States. It reviews events that have brought Cubans to the United States, and discusses the values newcomers are likely to have brought with…

  3. Rotor-stator molecular crystals of fullerenes with cubane.

    PubMed

    Pekker, Sándor; Kováts, Eva; Oszlányi, Gábor; Bényei, Gyula; Klupp, Gyöngyi; Bortel, Gábor; Jalsovszky, István; Jakab, Emma; Borondics, Ferenc; Kamarás, Katalin; Bokor, Mónika; Kriza, György; Tompa, Kálmán; Faigel, Gyula

    2005-10-01

    Cubane (C8H8) and fullerene (C60) are famous cage molecules with shapes of platonic or archimedean solids. Their remarkable chemical and solid-state properties have induced great scientific interest. Both materials form polymorphic crystals of molecules with variable orientational ordering. The idea of intercalating fullerene with cubane was raised several years ago but no attempts at preparation have been reported. Here we show that C60 and similarly C70 form high-symmetry molecular crystals with cubane owing to topological molecular recognition between the convex surface of fullerenes and the concave cubane. Static cubane occupies the octahedral voids of the face-centred-cubic structures and acts as a bearing between the rotating fullerene molecules. The smooth contact of the rotor and stator molecules decreases significantly the temperature of orientational ordering. These materials have great topochemical importance: at elevated temperatures they transform to high-stability covalent derivatives although preserving their crystalline appearance. The size-dependent molecular recognition promises selective formation of related structures with higher fullerenes and/or substituted cubanes.

  4. Shapers of Their Destiny: A History of the Education of Cuban Children in the United States since 1959

    ERIC Educational Resources Information Center

    San Miguel, Guadalupe, Jr.

    2013-01-01

    Despite the significant presence of Cuban children in the U.S. public schools since the late 1950s, no historical interpretation of their educational experiences exists. This essay is the first to develop such an interpretation. It sketches, in broad strokes, the role that Cuban exiles and Cuban Americans played in shaping their children's…

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

    DTIC Science & Technology

    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

  6. Engaging Cuban Physicists Through the APS/CPS Partnership

    NASA Astrophysics Data System (ADS)

    Lerch, Irving A.; Lerch, Irving A.

    In his reflections on Cuban physics, Marcelo Alonso urges APS to take steps to promote interactions between Cuban and US physicists. As an introduction to Marcello's essay, this note will summarize past and current activities.

  7. 31 CFR 515.549 - Bank accounts and other property of non-Cuban citizens who were in Cuba on or after July 8, 1963.

    Code of Federal Regulations, 2010 CFR

    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...

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

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 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...

  9. 31 CFR 515.549 - Bank accounts and other property of non-Cuban citizens who were in Cuba on or after July 8, 1963.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 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...

  10. 31 CFR 515.549 - Bank accounts and other property of non-Cuban citizens who were in Cuba on or after July 8, 1963.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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...

  11. 31 CFR 515.549 - Bank accounts and other property of non-Cuban citizens who were in Cuba on or after July 8, 1963.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 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...

  12. The thermochemistry of cubane 50 years after its synthesis: a high-level theoretical study of cubane and its derivatives.

    PubMed

    Agapito, Filipe; Santos, Rui C; Borges dos Santos, Rui M; Martinho Simões, José A

    2015-03-26

    The gas-phase enthalpy of formation of cubane (603.4 ± 4 kJ mol(-1)) was calculated using an explicitly correlated composite method (W1-F12). The result obtained for cubane, together with the experimental value for the enthalpy of sublimation, 54.8 ± 2.0 kJ mol(-1), led to 548.6 ± 4.5 kJ mol(-1) for the solid-phase enthalpy of formation. This value is only 6.8 kJ mol(-1) higher than the 50-year-old original calorimetric result. The carbon-hydrogen bond dissociation enthalpy (C-H BDE) of cubane (438.4 ± 4 kJ mol(-1)), together with properties relevant for its experimental determination using gas-phase ion thermochemistry, namely the cubane gas-phase acidity (1704.6 ± 4 kJ mol(-1)), cubyl radical electron affinity (45.8 ± 4 kJ mol(-1)), cubane ionization energy (1435.1 ± 4 kJ mol(-1)), cubyl radical cation proton affinity (918.8 ± 4 kJ mol(-1)), cubane cation appearance energy (1099.6 ± 4 kJ mol(-1)), and cubyl ionization energy (661.2 ± 4 kJ mol(-1)), were also determined. These values were compared with those calculated for unstrained hydrocarbons (viz., methane, ethane, and isobutane). The strain energy of cubane (667.2 kJ mol(-1)) and cubyl radical (689.4 kJ mol(-1)) were independently estimated via quasihomodesmotic reactions. These values were related via a simple model to the C-H BDE in cubane. Taking into account the accuracy of the computational method, the comparison with high-precision experimental results, and the data consistency afforded by the relevant thermodynamic cycles, we claim an uncertainty better than ±4 kJ mol(-1) for the new enthalpy of formation values presented.

  13. 76 FR 5072 - Cuban Assets Control Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-28

    ... DEPARTMENT OF THE TREASURY Office of Foreign Assets Control 31 CFR Part 515 Cuban Assets Control Regulations AGENCY: Office of Foreign Assets Control, Treasury. ACTION: Final rule. SUMMARY: The Department of the Treasury's Office of Foreign Assets Control (``OFAC'') is amending the Cuban Assets Control...

  14. 77 FR 71530 - Cuban Assets Control Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-03

    ... DEPARTMENT OF THE TREASURY Office of Foreign Assets Control 31 CFR Part 515 Cuban Assets Control Regulations AGENCY: Office of Foreign Assets Control, Treasury. ACTION: Final rule. SUMMARY: The Department of the Treasury's Office of Foreign Assets Control (``OFAC'') is amending the Cuban Assets Control...

  15. 75 FR 10996 - Cuban Assets Control Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-10

    ... DEPARTMENT OF THE TREASURY Office of Foreign Assets Control 31 CFR Part 515 Cuban Assets Control Regulations AGENCY: Office of Foreign Assets Control, Treasury. ACTION: Final rule. SUMMARY: The Department of the Treasury's Office of Foreign Assets Control (``OFAC'') is amending the Cuban Assets Control...

  16. 45 CFR 400.62 - Treatment of eligible secondary migrants, asylees, and Cuban/Haitian entrants.

    Code of Federal Regulations, 2010 CFR

    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...

  17. 8 CFR 212.12 - Parole determinations and revocations respecting Mariel Cubans.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Parole determinations and revocations respecting Mariel Cubans. 212.12 Section 212.12 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY... ALIENS; PAROLE § 212.12 Parole determinations and revocations respecting Mariel Cubans. (a) Scope. This...

  18. 8 CFR 212.12 - Parole determinations and revocations respecting Mariel Cubans.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Parole determinations and revocations respecting Mariel Cubans. 212.12 Section 212.12 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY... ALIENS; PAROLE § 212.12 Parole determinations and revocations respecting Mariel Cubans. (a) Scope. This...

  19. 8 CFR 212.12 - Parole determinations and revocations respecting Mariel Cubans.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Parole determinations and revocations respecting Mariel Cubans. 212.12 Section 212.12 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY... ALIENS; PAROLE § 212.12 Parole determinations and revocations respecting Mariel Cubans. (a) Scope. This...

  20. Cuban Roosters

    ERIC Educational Resources Information Center

    Henn, Cynthia

    2004-01-01

    The rooster is an important symbol in Cuban culture. It represents strength and power. It is considered a compliment for a male to be called a rooster. Jesus Rivera, a folk artist, who is best known for using Cuban symbolism in his ceramics and illustrations, visited the class described in this article. Senor Rivera described the culture of Cuba…

  1. My Collaboration with Cuban Physicists

    NASA Astrophysics Data System (ADS)

    Leccabue, Fabrizio

    My first meeting with the scientific Cuban community was in 1969 when the first of four young Cuban physicists, Joaquín Torres Orosco†, came to the Physics Department of Parma University through the `Andrea Levialdi Fellowship,' an Italian bursary promoted by Roberto Fieschi using a fund, subscribed to voluntarily by the Italian physics community.

  2. Phylogenetic analysis of human immunodeficiency virus type 2 isolated from Cuban individuals.

    PubMed

    Machado, Liuber Y; Díaz, Héctor M; Noa, Enrique; Martín, Dayamí; Blanco, Madeline; Díaz, Dervel F; Sánchez, Yordank R; Nibot, Carmen; Sánchez, Lourdes; Dubed, Marta

    2014-08-01

    The presence of infection by human immunodeficiency virus type 2 (HIV-2) in Cuba has been previously documented. However, genetic information on the strains that circulate in the Cuban people is still unknown. The present work constitutes the first study concerning the phylogenetic relationship of HIV-2 Cuban isolates conducted on 13 Cuban patients who were diagnosed with HIV-2. The env sequences were analyzed for the construction of a phylogenetic tree with reference sequences of HIV-2. Phylogenetic analysis of the env gene showed that all the Cuban sequences clustered in group A of HIV-2. The analysis indicated several independent introductions of HIV-2 into Cuba. The results of the study will reinforce the program on the epidemiological surveillance of the infection in Cuba and make possible further molecular evolutionary studies.

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

    PubMed

    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)

  4. Contemporary Cuban Physics Through Scientific Publications: An Insider’s View

    NASA Astrophysics Data System (ADS)

    Altshuler, Ernesto

    In a previous paper, the author reached some conclusions on the tendencies of the publications by Cuban physicists in international journals (Altshuler, Rev Cub Fís 22(2):173-182, 2005) and called for a systematic bibliometric study of the subject. Such a study has now been undertaken (a contribution to this volume entitled "Physics in Cuba from the Perspective of Bibliometrics" by Werner Marx and Manuel Cardona, referred to in this paper as Marx and Cardona) and supports the main conclusions of the former work. The scenario of Cuban physics since 1995 has been conditioned by two main facts interacting in a nontrivial way: the serious material shortages affecting local physics laboratories and bibliographic resources, and an increase in the country's international collaboration. As a positive result, the total volume of Cuban publications in international physics journals has increased since 1995, perhaps reaching a peak around the year 2000, while the number of citations of Cuban papers and the impact of the journals in which they were published have continued to increase since the mid-1990s. Theoretical work produced by physicists from a number of Cuban institutions in international collaborations strongly contribute to those numbers. In the last years, international publications suggest a `self-organized' opening of Cuban physics towards interdisciplinary subjects, which is increasing the `bibliometric visibility' of autochthonous experimental work.

  5. Field-Independence: A Function of Sex and Socialization in Cuban and American Adolescents.

    ERIC Educational Resources Information Center

    Britain, Susan D.; Abad, Marcy

    The relationship between field-dependence and cultural biases towards control and discipline practices was explored. It was hypothesized that the strict control practices described for the Cuban culture would foster greater field-dependence in their adolescents than would the practice of a U. S. born group. Seventy-two Cuban and U. S. born…

  6. Cuban Value Orientations. Cultural Monograph Number 1. Bilingual Multicultural Education Training Project for School Psychologists and Guidance Counselors.

    ERIC Educational Resources Information Center

    Florida Univ., Gainesville. Coll. of Education.

    Information is provided in this monograph to facilitate understanding of Cuban cultural values and their implications for counseling limited English proficient students. Also provided is a beginning conceptual model for increasing the understanding of cross-cultural theory and practice. The overview of Cuban culture is based on a perspective of…

  7. Race, Wages, and Assimilation among Cuban Immigrants. Working Paper.

    ERIC Educational Resources Information Center

    Zavodny, Madeline

    This study uses data from the 1980 and 1990 Census and the 1994-2000 Current Population Survey to examine the determinants of earnings among male Cuban immigrants in the United States by race. Nonwhite Cuban immigrants earn about 15 percent less than Whites, on average. Much of the racial wage gap is due to differences in educational attainment,…

  8. A Sociolinguistic Analysis of Final /s/ in Miami Cuban Spanish

    ERIC Educational Resources Information Center

    Lynch, Andrew

    2009-01-01

    This study analyzes the variation of syllable- and word-final /s/ among two generations of Cubans in Miami, Florida (USA): older, early exile immigrants who arrived in Miami as adults in the 1960s and 1970s, and young Miami-born Cubans whose maternal and paternal grandparents immigrated to Miami from Cuba prior to 1980. Since sibilant weakening is…

  9. Adaptation and Adjustment of Cubans: West New York, New Jersey. Monograph No. 5.

    ERIC Educational Resources Information Center

    Rogg, Eleanor Meyer; Cooney, Rosemary Santana

    This monograph reports on a study that examined the adaptation and adjustment of Cuban migrants in West New York, New Jersey. Data were collected through interviews with the heads of 300 Cuban families. A review of relevant literature and an overview of the research design and methodology are presented in Chapter 1. Chapter 2 provides descriptive…

  10. 3 CFR - Delegation of Authority To Suspend the Provisions of Title III of the Cuban Liberty and...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 3 The President 1 2014-01-01 2014-01-01 false Delegation of Authority To Suspend the Provisions of Title III of the Cuban Liberty and Democratic Solidarity (LIBERTAD) Act of 1996 Presidential Documents Other Presidential Documents Memorandum of January 31, 2013 Delegation of Authority To Suspend the Provisions of Title III of the Cuban Liberty...

  11. Cuban Support to Latin American and Caribbean Insurgencies: 1978-1983.

    DTIC Science & Technology

    1985-09-01

    Jamaican students still in Cuba were recalled. Still, 15 Cubans continued to conduct intelligence operations out of the Embassy. In October 1981...informal emancipation policies, whites, blacks, and Indians integrated themselves into a nation unique among the remaining settlememts in Latin America...fears. The growing anti-imperialist consensus among the intellectual segments of Cuban society was exacerbated by the repressive tactics of Gerardo

  12. Adult School for Cuban Refugees, Fort Indiantown Gap, Pennsylvania. Final Report, August 25-November 28, 1980.

    ERIC Educational Resources Information Center

    Central Susquehanna Intermediate Unit 16, Lewisburg, PA.

    The Adult School for Cuban Refugees, operated by the Central Susquehanna Intermediate Unit in 1980, supplied services to approximately 1,200 Cuban refugees in the six weeks of its operation at Fort Indiantown Gap, Pennsylvania. The program offered basic oral English classes to adults ranging in age from 18 to 81 years. The classes were conducted…

  13. What determines catalyst functionality in molecular water oxidation? Dependence on ligands and metal nuclearity in cobalt clusters.

    PubMed

    Smith, Paul F; Kaplan, Christopher; Sheats, John E; Robinson, David M; McCool, Nicholas S; Mezle, Nicholas; Dismukes, G Charles

    2014-02-17

    The metal-oxo M4O4 "cubane" topology is of special significance to the field of water oxidation as it represents the merging of bioinspired structural principles derived from natural photosynthesis with successful artificial catalysts known to date. Herein, we directly compare the rates of water oxidation/O2 evolution catalyzed by six cobalt-oxo clusters including the Co4O4 cubanes, Co4O4(OAc)4(py)4 and [Co4O4(OAc)2(bpy)4](2+), using the common Ru(bpy)3(2+)/S2O8(2-) photo-oxidant assay. At pH 8, the first-order rate constants for these cubanes differ by 2-fold, 0.030 and 0.015 s(-1), respectively, reflecting the number of labile carboxylate sites that allow substrate water binding in a pre-equilibrium step before O2 release. Kinetic results reveal a deprotonation step occurs on this pathway and that two electrons are removed before O2 evolution occurs. The Co4O4 cubane core is shown to be the smallest catalytic unit for the intramolecular water oxidation pathway, as neither "incomplete cubane" trimers [Co3O(OH)3(OAc)2(bpy)3](2+) and [Co3O(OH)2(OAc)3(py)5](2+) nor "half cubane" dimers [Co2(OH)2(OAc)3(bpy)2](+) and [Co2(OH)2(OAc)3(py)4](+) were found capable of evolving O2, despite having the same ligand sets as their cubane counterparts. Electrochemical studies reveal that oxidation of both cubanes to formally Co4(3III,IV) (0.7 V vs Ag/AgCl) occurs readily, while neither dimers nor trimers are oxidized below 1.5 V, pointing to appreciably greater charge delocalization in the [Co4O4](5+) core. The origin of catalytic activity by Co4O4 cubanes illustrates three key features for water oxidation: (1) four one-electron redox metals, (2) efficient charge delocalization of the first oxidation step across the Co4O4 cluster, allowing for stabilization of higher oxidizing equivalents, and (3) terminal coordination site for substrate aquo/oxo formation.

  14. Black Youth in Cuba

    ERIC Educational Resources Information Center

    Horne, Gerald C.

    1975-01-01

    Cuban social system has eliminated discrimination, racism, sexism and unemployment and created equal opportunity for all. Cuba is upheld as model for all forward looking U.S. citizens to study. (Author/AM)

  15. What percentage of the Cuban HIV-AIDS epidemic is known?

    PubMed

    de Arazoza, Héctor; Lounes, Rachid; Pérez, Jorge; Hoang, Thu

    2003-01-01

    The data for the Cuban HIV-AIDS epidemic from 1986 to 2000 were presented. With the purpose of evaluating the efficiency of the HIV detection system, two methods were used to estimate the size of the HIV-infected population, backcalculation and a dynamical model. From these models it can be estimated that in the worst scenario 75% of the HIV-infected persons are known and in the best case 87% of the total number of persons that have been infected with HIV have been detected by the National Program. These estimates can be taken as a measure of the efficiency of the detection program for HIV-infected persons.

  16. Eating Behaviors in Cuban Adults: Results from an Exploratory Transcultural Study

    PubMed Central

    Rodríguez-Martín, Boris C.; Innamorati, Marco; Imperatori, Claudio; Fabbricatore, Mariantonietta; Harnic, Désirée; Janiri, Luigi; Rivas-Suárez, Saira R.

    2016-01-01

    This study aims to investigate eating behaviors in Cuban adults and compare them with those of a developed Western country, Italy. The study also aimed to determine the overall accuracy of a predictive model intended to define variables which could be used to discriminate between nationalities. Participants were 283 normal weight individuals from Cuba (n = 158) and Italy (n = 125). Italians had higher scores for restrained eating on the questionnaire than Cubans with a considerable effect size. This trend was also found for emotional eating and binge eating, as well as number of current dieters, despite the fact that effect sizes were small. On the other hand, Cubans, when compared to Italians reported higher scores for food thought suppression with reward responsiveness and restrained eating emerging as significant predictors of between-country differences. To conclude, eating behaviors in Cubans could be different from those reported in European countries, perhaps as a consequence of Cuba’s recent history. PMID:27725806

  17. The U.S. Embargo on Cuba: A time for Change?

    DTIC Science & Technology

    2003-06-06

    to protect intellectual property rights. This is tantamount to Cuba producing an American product like Coke or Pepsi and selling it as a Cuban product...intended audience . Primarily because the Cuban Government jams the signal and secondly because it is transmitted between the hours of 0330 and 0800...Cuban broadcast transmissions during prime time hours. Radio Marti’s listening audience has declined to an estimated five percent of the

  18. Cuban Epidemic optic neuropathy (1991-1993) And josé saramago's novel blindness (1995).

    PubMed

    Feibel, Robert M; Arch, Jennifer

    2018-06-12

    This article reviews the history of Cuban Epidemic Optic Neuropathy (1991-1993), which caused visual loss, peripheral neuralgias, and other neurological symptoms in over 50,000 persons, an incidence of almost 0.5% of the entire population. The clinical findings, etiology, and treatment are described. We then relate the Cuban epidemic to the fictional epidemic of contagious blindness depicted by Nobel Laureate José Saramago in his 1995 novel Blindness. This novel describes an unnamed modern city in which all inhabitants, except the ophthalmologist's wife, are affected with a white, not black, blindness. Historical review and literary essay. The sources for the Cuban epidemic were an extensive review of the published literature and personal communications with physicians who treated these patients. Both authors have analyzed the novel and the critical literature about Saramago's writings. Though Saramago uses the epidemic of blindness as an allegory to comment on human weakness and immorality, he may also have known of the actual Cuban epidemic. Saramago was a lifelong member of the Communist party, as well as a friend of Fidel Castro and admirer of the Cuban government. We have no proof that Blindness was influenced by the Cuban epidemic, but we find it plausible. It is valuable to examine the real and fictional epidemics side by side, not least because Saramago's novel depicts the actions of an ophthalmologist during an epidemic of blindness. Ophthalmologists may be interested in a novel that uses the language of eyes, vision, sight, and blindness extensively. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Superconductivity in Cuba: Reaching the Frontline

    NASA Astrophysics Data System (ADS)

    Arés Muzio, Oscar; Altshuler, Ernesto

    The start of experimental research in the field of superconductivity was a very special moment for Cuban physics: Cuban scientists at the Physics Faculty, University of Havana, synthesized the first Cuban superconductor (a 123-YBCO ceramic sample) just 2 months after the publication of the famous paper by Wu and co-workers that triggered the frantic race of High Tc superconductors all over the world. We timely joined the world's frontline in superconductor research.

  20. Cubanes: Super explosives and potential pharmaceutical intermediates

    NASA Technical Reports Server (NTRS)

    Bashir-Hashemi, A.

    1994-01-01

    The cubane molecule, in which eight carbon atoms are locked in a cubic framework, shows great potential for both military and pharmaceutical applications. Octanitrocubane, with a predicted density of 2.1 g/cc and strain energy of more than 165 kcal/mol, is considered to be the 'super-explosive', while cubane derivatives submitted to the National Institutes of Health for preliminary biological activity screening have displayed promising anti-cancer and anti-HIV activity.

  1. Daughters caregiving for Hispanic and non-Hispanic Alzheimer patients: does ethnicity make a difference?

    PubMed

    Mintzer, J E; Rubert, M P; Loewenstein, D; Gamez, E; Millor, A; Quinteros, R; Flores, L; Miller, M; Rainerman, A; Eisdorfer, C

    1992-08-01

    This study assessed Cuban-American Hispanic and White non-Hispanic daughters who were major caregivers for their mothers suffering from Alzheimer's Disease. Although patients in both ethnic groups did not differ in their level of cognitive and functional impairment, Cuban-American Hispanic patients were significantly more likely to be living in their daughters' homes while the White non-Hispanic patients resided in institutional settings. Caregivers were equivalent in their knowledge and utilization of community services, but Cuban-American daughters were significantly more aware of financial aid resources. Cuban-American patients were significantly more depressed than their White non-Hispanic counterparts with daughters showing similar but nonsignificant trends. The impact of cultural factors on caregiving is discussed.

  2. Genetic types of oils in the petroliferous basins of Cuba

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maksimov, S.P.; Botneva, T.A.; Pankina, R.G.

    Two oil- and gas basins, the North Cuban and the Central Cuban, have been discovered in Cuba and the nearby offshore areas. The North Cuban basin developed as a result of a complete cycle of inter-plate geodynamic evolution (divergence-convergence-isostatic adjustment of the plates), and the South Cuban basin formed during the phase of convergence and isostatic adjustment of the plates. The hydrocarbon deposits discovered in the North Cuban basin are marked by their exceptional variety, and include deposits of light and heavy oils, and even asphalt. The geological conditions of their occurrence are also varied. In this paper the authorsmore » present the results of a study of the oils and a discussion of their association with the source beds. For Cuba the solution of these problems is of special importance owing to the complexity of its geological structure and, in particular, the presence of oil deposits of varied composition in the overthrust complexes of the eugeosynclinal and miogeosynclinal allochthon and para-autochthon, as well as in the sediments of the autochthonous complex. 4 references.« less

  3. Huddling with the honchos in Havana

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mendelsohn, J.

    1993-09-01

    The economic collapse following the Soviet Union's disintegration has affected all aspects of life in Cuba. In this paper Cuban foreign policy and defense is discussed. This article evaluates the energy situation of Cuba (oil imports), food shortages, Cuba's position on the Treaty of Tlatelolco (formally, the Treaty for the Prohibition of Nuclear Weapons in Latin America), Cuba's nuclear power projects, and discussions concerning Cuban involvement in biological warfare. The effects of U.S. military activities on U.S.-Cuban relations are emphasized. 8 refs.

  4. USSR Report, International Affairs, The Working Class and the Contemporary World No 3, May-June 1986

    DTIC Science & Technology

    1986-10-24

    experts were intro- duced into production. 14. 1st Cuban Communist Party Congress, p 441. 15. JUVENTUD REBELDE, 4 February 1975; GRANMA, 21 December...1st Cuban Communist Party Congress, p 440. 22. JUVENTUD REBELDE, 4 February, 1975. 23 Cf • Sheynin, E. Ya. Course of the Cuban Communist Party...31. GRANMA, 1 December 1978. 32. JUVENTUD REBELDE, 2 June, 1975. 33. GRANMA, -21, February 1984. 34. Ibidem. 35. GRANMA, 1 December, 1978; 19

  5. 31 CFR 515.206 - Exempt transactions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Cuban film in any medium, including home video distribution, for five years, with the Cuban party... national with respect to income received for enhancements or alterations made by persons subject to the...

  6. 31 CFR 515.206 - Exempt transactions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Cuban film in any medium, including home video distribution, for five years, with the Cuban party... national with respect to income received for enhancements or alterations made by persons subject to the...

  7. 31 CFR 515.206 - Exempt transactions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Cuban film in any medium, including home video distribution, for five years, with the Cuban party... national with respect to income received for enhancements or alterations made by persons subject to the...

  8. 31 CFR 515.206 - Exempt transactions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Cuban film in any medium, including home video distribution, for five years, with the Cuban party... national with respect to income received for enhancements or alterations made by persons subject to the...

  9. Lessons from the margins of globalization: appreciating the Cuban health paradox.

    PubMed

    Spiegel, Jerry M; Yassi, Annalee

    2004-01-01

    It is widely recognized that Cuba, despite poor economic performance, has achieved and sustained health indices comparable to those in developed countries--the Cuban Paradox. There has been, however, remarkably little scholarship evaluating how this has been accomplished, especially during a period of extreme economic hardship. Cuba's exclusion from the mainstream of "globalization," moreover, allows us to gain insights into the population health impact of policies that have accompanied globalization. Cuba's experience challenges the conventional assumption that generating wealth is the fundamental precondition for improving health. As peoples around the world search for cost-effective ways to improve well-being, they might want to learn how alternative public policy approaches, such as those used in Cuba, may be effective. We therefore reviewed the literature on the health-wealth relationship in this globalizing era; then systematically examined public policy in Cuba, not only for health services (financing, vertical and horizontal integration, prevention and primary-care focus, inter-sectoral linkages, etc.) but for non-medical determinants of health as well. These included education, housing, nutrition, employment, etc. plus the community mobilization and social cohesion that the Cuban system has generated. It appears that the active implementation of public policy affecting a wide variety of health determinants explains the Cuban paradox, and that the international community can learn from Cuba's experience. The prospect for healthy public policy can thus exist within, rather than only on the margins of globalization. The importance of monitoring how Cuba sustains such policies as it faces growing challenges in this globalizing era is increasingly worth observing.

  10. The 1980 Cuban Crisis: Some Observations.

    ERIC Educational Resources Information Center

    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)

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

    USGS Publications Warehouse

    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.

  12. Health education in Cuba: a preface.

    PubMed

    Tesh, S

    1986-01-01

    Critics of health education policy in the United States fault it for ignoring the unequal ability of Americans to adopt more healthy behavior and for underestimating the social, economic, and political causes of disease. Many critics hypothesize that health education in a less bourgeois society would be more equitable and less individualistic. This article tests that hypothesis by analyzing the current Cuban health education program aimed at the reduction of chronic diseases. It argues that while the Cuban program appears to be every bit as individualistic as the North American program, theirs may not be comparable to ours because Cubans are less likely than Americans to reify the state. At least among supporters of the revolution, Cubans do not automatically make a conceptual distinction between the individual and the society. Discussions about responsibility for disease prevention take on new meaning in this light.

  13. The cytotoxic effects of brown Cuban propolis depend on the nemorosone content and may be mediated by mitochondrial uncoupling.

    PubMed

    Pardo Andreu, Gilberto L; Reis, Felippe H Z; Dalalio, Felipe M; Nuñez Figueredo, Yanier; Cuesta Rubio, Osmany; Uyemura, Sergio A; Curti, Carlos; Alberici, Luciane C

    2015-02-25

    Three main types of Cuban propolis directly related to their secondary metabolite composition have been identified: brown, red and yellow propolis; the former is majoritarian and is characterized by the presence of nemorosone. In this study, brown Cuban propolis extracts were found cytotoxic against HepG2 cells and primary rat hepatocytes, in close association with the nemorosone contents. In mitochondria isolated from rat liver the extracts displayed uncoupling activity, which was demonstrated by the increase in succinate-supported state 4 respiration rates, dissipation of mitochondrial membrane potential, Ca(2+) release from Ca(2+)-loaded mitochondria, and a marked ATP depletion. As in cells, the degree of such mitotoxic events was closely correlated to the nemorosone content. The propolis extracts that do not contain nemorosone were neither cytotoxic nor mitotoxic, except R-29, whose detrimental effect upon cells and mitochondria could be mediated by its isoflavonoids and chalcones components, well known mitochondrial uncouplers. Our results at least partly unravel the cytotoxic mechanism of Cuban propolis, particularly regarding brown propolis, and raise concerns about the toxicological implication of Cuban propolis consumption. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. Artificial Metalloproteins Containing Co 4O 4Cubane Active Sites

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Olshansky, Lisa; Huerta-Lavorie, Raul; Nguyen, Andy I.

    Artificial metalloproteins (ArMs) containing Co 4O 4 cubane active sites were constructed via biotin-streptavidin technology. Stabilized by hydrogen bonds (H-bonds), terminal and cofacial Co III-OH 2 moieties are observed crystallographically in a series of immobilized cubane sites. Solution electrochemistry provided correlations of oxidation potential and pH. For variants containing Ser and Phe adjacent to the metallocofactor, 1e -/1H + chemistry predominates until pH 8, above which the oxidation becomes pH-independent. Installation of Tyr proximal to the Co 4O 4 active site provided a single H-bond to one of a set of cofacial Co III-OH 2 groups. With this variant, multi-emore » - /multi-H + chemistry is observed, along with a change in mechanism at pH 9.5 that is consistent with Tyr deprotonation. Finally, with structural similarities to both the oxygen-evolving complex of photosystem II (H-bonded Tyr) and to thin film water oxidation catalysts (Co 4O 4 core), these findings bridge synthetic and biological systems for water oxidation, highlighting the importance of secondary sphere interactions in mediating multi-e - /multi-H + reactivity.« less

  15. Artificial Metalloproteins Containing Co 4O 4Cubane Active Sites

    DOE PAGES

    Olshansky, Lisa; Huerta-Lavorie, Raul; Nguyen, Andy I.; ...

    2018-02-05

    Artificial metalloproteins (ArMs) containing Co 4O 4 cubane active sites were constructed via biotin-streptavidin technology. Stabilized by hydrogen bonds (H-bonds), terminal and cofacial Co III-OH 2 moieties are observed crystallographically in a series of immobilized cubane sites. Solution electrochemistry provided correlations of oxidation potential and pH. For variants containing Ser and Phe adjacent to the metallocofactor, 1e -/1H + chemistry predominates until pH 8, above which the oxidation becomes pH-independent. Installation of Tyr proximal to the Co 4O 4 active site provided a single H-bond to one of a set of cofacial Co III-OH 2 groups. With this variant, multi-emore » - /multi-H + chemistry is observed, along with a change in mechanism at pH 9.5 that is consistent with Tyr deprotonation. Finally, with structural similarities to both the oxygen-evolving complex of photosystem II (H-bonded Tyr) and to thin film water oxidation catalysts (Co 4O 4 core), these findings bridge synthetic and biological systems for water oxidation, highlighting the importance of secondary sphere interactions in mediating multi-e - /multi-H + reactivity.« less

  16. Patterns of Caregiving of Cuban, Other Hispanic, Caribbean Black, and White Elders in South Florida

    PubMed Central

    Buckwalter, Kathleen C.; Newman, Frederick L.; Mauro, Ana C.

    2013-01-01

    Caregivers in Miami, Florida (185 Cubans, 108 other Hispanics, 229 non-Hispanic Whites, and 73 Caribbean Blacks) were described and compared along demographic and health variables, cultural attitudes, and caregiving behaviors. Participants were recruited at random through Home Health Services (61 %) and convenience sampling in the community (39 %), and interviewed at their home. Standardized instruments and measures constructed for this study were pretested. Multivariate analyses showed that the ethnic groups differed in age, education, income, and number of persons giving care, while caregiver health and patient functioning were similar. Controlling for demographics, differences in cultural variables were small. The sense of obligation, emotional attachment, openness about who should give care, spirituality, use of family help or community services were comparable in all groups. Commitment to caregiving was high, driven mainly by patient needs. Cubans had the greatest family stability, and worked the hardest, with the lowest sense of burden. Caribbean Black caregivers lived in bigger families, were youngest, and their patients had the lowest cognitive status. Burden was felt most by White caregivers who were older than the others. Professionals need to understand complex belief systems and behavior patterns to assist caregivers in mobilizing appropriate resources. PMID:23636833

  17. Developing nursing capacity for health systems and services research in Cuba, 2008-2011.

    PubMed

    Martínez, Nelcy

    2012-07-01

    Health systems and services research by nursing personnel could inform decision-making and nursing care, providing evidence concerning quality of and patient satisfaction. Such studies are rather uncommon in Cuban research institutes, where clinical research predominates. Assess the results of a strategy implemented between 2008 and 2011 to develop nursing capacity for health systems and services research in 14 national research institutes based in Havana. The study comprised four stages: description of approaches to health systems and services research by nurses worldwide and in Cuba; analysis of current capacities for such research in Cuba; intervention design and implementation; and evaluation. Various techniques were used including: literature review, bibliometric analysis, questionnaire survey, consultation with experts, focus groups, and workshops for participant orientation and design and followup of research projects. Qualitative information reduction and quantitative information summary methods were used. Initially, 32 nursing managers participated; a further 105 nurses from the institutes were involved in research teams formed during intervention implementation. Of all published nursing research articles retrieved, 8.9% (185 of 2081) concerned health systems and services research, of which 26.5% (49 of 185) dealt with quality assessment. At baseline, 75% of Cuban nurses surveyed had poor knowledge of health systems and services research. Orientation, design and followup workshops for all institute teams developed individual and institutional capacity for health systems and services research. Post-intervention, 84.7% (27) of nurses reached good knowledge and 14.3% (5) fair; institutional research teams were formed and maintained in 9 institutes, and 13 projects designed and implemented (11 institutional, 2 addressing ministerial-level priorities) to research nursing issues at selected centers. A systematic strategy to build nursing capacity for health systems and services research can be effective in involving nurses in such research and in developing institutional support for it, fostering compliance with Cuban and international professional development priorities for nursing, as well as contributing to quality of patient services.

  18. Comparison of the Manganese Cluster in Oxygen-Evolving Photosystem II with Distorted Cubane Manganese Compounds through X-ray Absorption Spectroscopy

    PubMed Central

    Cinco, Roehl M.; Rompel, Annette; Visser, Hendrik; Aromí, Guillem; Christou, George; Sauer, Kenneth; Klein, Melvin P.; Yachandra, Vittal K.

    2014-01-01

    X-ray absorption spectroscopy has been employed to assess the degree of similarity between the oxygen-evolving complex (OEC) in photosystem II (PS II) and a family of synthetic manganese complexes containing the distorted cubane [Mn4O3X] core (X = benzoate, acetate, methoxide, hydroxide, azide, fluoride, chloride, or bromide). These [Mn4(μ3-O)3(μ3-X)] cubanes possess C3v symmetry except for the X = benzoate species, which is slightly more distorted with only Cs symmetry. In addition, Mn4O3Cl complexes containing three or six terminal Cl ligands at three of the Mn were included in this study. The Mn K-edge X-ray absorption near edge structure (XANES) from the oxygen-ligated complexes begin to resemble general features of the PS II (S1 state) spectrum, although the second derivatives are distinct from those in PS II. The extended X-ray absorption fine structure (EXAFS) of these Mn compounds also displays superficial resemblance to that of PS II, but major differences emerge on closer examination of the phases and amplitudes. The most obvious distinction is the smaller magnitude of the Fourier transform (FT) of the PS II EXAFS compared to the FTs from the distorted cubanes. Curve fitting of the Mn EXAFS spectra verifies the known core structures of the Mn cubanes, and shows that the number of the crucial 2.7 and 3.3 Å Mn–Mn distances differs from that observed in the OEC. The EXAFS method detects small changes in the core structures as X is varied in this series, and serves to exclude the distorted cubane of C3v symmetry as a topological model for the Mn catalytic cluster of the OEC. Instead, the method shows that even more distortion of the cubane framework, altering the ratio of the Mn–Mn distances, is required to resemble the Mn cluster in PS II. PMID:11671305

  19. A Cuban tektite

    USGS Publications Warehouse

    Garlick, G.D.; Naeser, C.W.; O'Neil, J.R.

    1971-01-01

    A large tektite from Cuba is classified with other North American tektites on the basis of its age. The major-element chemistry, oxygen isotopic composition, refractive index and density of the Cuban tektite are within the ranges exhibited by bediasites. ?? 1971.

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

    USGS Publications Warehouse

    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.

  1. 31 CFR 515.575 - Humanitarian projects.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY CUBAN ASSETS CONTROL REGULATIONS Licenses... Cuba not otherwise covered by this part that are designed to directly benefit the Cuban people. Such... intended to benefit legitimately independent civil society groups; environmental projects; projects...

  2. 31 CFR 515.575 - Humanitarian projects.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY CUBAN ASSETS CONTROL REGULATIONS Licenses... Cuba not otherwise covered by this part that are designed to directly benefit the Cuban people. Such... intended to benefit legitimately independent civil society groups; environmental projects; projects...

  3. 31 CFR 515.575 - Humanitarian projects.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY CUBAN ASSETS CONTROL REGULATIONS Licenses... Cuba not otherwise covered by this part that are designed to directly benefit the Cuban people. Such... intended to benefit legitimately independent civil society groups; environmental projects; projects...

  4. 31 CFR 515.575 - Humanitarian projects.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY CUBAN ASSETS CONTROL REGULATIONS Licenses... Cuba not otherwise covered by this part that are designed to directly benefit the Cuban people. Such... intended to benefit legitimately independent civil society groups; environmental projects; projects...

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

    ERIC Educational Resources Information Center

    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)

  6. Systemic Success in Physical Education: The East Valley Phenomenon

    ERIC Educational Resources Information Center

    Prusak, Keven A.; Pennington, Todd; Graser, Susan Vincent; Beighle, Aaron; Morgan, Charles F.

    2010-01-01

    Siedentop and Locke (1997) proposed three critical elements that must exist in our profession to make a difference and achieve systemic success in physical education (SSPE): (a) quality PE in the schools, (b) effective physical education teacher education (PETE)programs, and (c) a working relationship between the two. Using Cuban's (1992)…

  7. "No one left abandoned": Cuba's national health system since the 1959 revolution.

    PubMed

    De Vos, Pol

    2005-01-01

    In spite of the economic hardships during the 1990s, Cuba has achieved health indicators that are among the best in the world. This article describes the development of the Cuban health system over more than four decades and analyzes its dynamics. Four stages can be identified. The system's foundations were laid during the first post-revolutionary decade (1959--1970) and consolidated during the succeeding decade (1970--1979). In the third stage, from 1980 onward, the system reached its full expansion with the development of family medicine. Following the crisis of the 1990s, a fourth stage began with reforms and adjustments to the new situation after the collapse of the Soviet Union. Today, health care continues to be of high quality and free for all Cubans. It remains exclusively in the hands of the public sector, and privatization is not an option. This is exactly the opposite of what is happening in other parts of the world where public services are underfunded and people are made to believe that privatization is the only way to ensure high-quality care.

  8. Professional Adaptation of the Cuban Electrical Engineer in the U. S., 1959-69

    ERIC Educational Resources Information Center

    Moncarz, Raul

    1972-01-01

    An analysis of the re-adaptation of education and training brought to the U.S. by Cuban electrical engineers in an effort to discover which personal and occupational characteristics provided better adjustment to the new environment. (Author/PR)

  9. Cuban Epidemic Neuropathy: Insights into the Toxic-Nutritional Hypothesis through International Collaboration.

    PubMed

    González-Quevedo, Alina; Santiesteban-Freixas, Rosaralis; Eells, Janis T; Lima, Lucimey; Sadun, Alfredo A

    2018-04-01

    From 1991 to 1993, an epidemic of optic and peripheral neuropathy-the largest of the century-broke out in Cuba, affecting more than 50,000 people. Initially the main clinical features were decreased visual acuity, central and cecocentral scotomas, impaired color vision and absence of the papillomacular bundle. Later, peripheral and mixed optic-peripheral forms began to appear. Due to the magnitude of the epidemic, the Cuban government requested help from the international community at the 46th World Health Assembly in 1993. PAHO and WHO immediately responded by sending a mission of international experts. Several hypotheses regarding the pathogenesis of Cuban epidemic neuropathy were put forward including: toxic, nutritional, genetic and infectious. The authors refer to extensive studies by researchers sponsored by the Cuban government and PAHO/WHO, joined by scientists from several other countries, including the USA. This paper describes their multidisciplinary work, particularly devoted to investigating the hypothesis of a primary toxic-nutritional cause of the epidemic. Clinical aspects, such as case definition and clinical description, were vital issues from the start. Cuban physicians who first examined patients received a clear impression of its toxic-nutritional origin, later confirmed by international experts. Research then focused on the mechanisms contributing to damage under the toxic-nutritional hypothesis. These included injuries to the mitochondrial oxidative phosphorylation pathway, nutritional deficiencies, excitotoxicity, formate toxicity and dysfunction of the blood-brain barrier. It was expected that the results of such international collaboration into this major health problem would also shed more light on mechanisms underlying other nutritional or tropical myeloneuropathies. KEYWORDS Optic neuritis, optic neuropathy, peripheral neuropathy, neurotoxicity syndromes, disease outbreaks, international cooperation, Cuba Erratum: Page 30, first complete paragraph, line 7, "Two models were developed independently by Cuban researchers" should read "Two models were developed independently by AAS and AGQ."

  10. Cardiovascular Disease and Associated Risk Factors in Cuba: Prospects for Prevention and Control

    PubMed Central

    Cooper, Richard S.; Orduñez, Pedro; Iraola Ferrer, Marcos D.; Munoz, Jose Luis Bernal; Espinosa-Brito, Alfredo

    2006-01-01

    Objectives. An adequate description of the trends in cardiovascular disease (CVD) is not available for most of the developing world. Cuba provides an important exception, and we sought to use available data to offer insights into the changing patterns of CVD there. Methods. We reviewed Cuban public health statistics, surveys, and reports of health services. Results. CVD has been the leading cause of death since 1970. A 45% reduction in heart disease deaths was observed from 1970 to 2002; the decline in stroke was more limited. There are moderate prevalences of all major risk factors. Conclusions. The Cuban medical care system has responded vigorously to the challenge of CVD; levels of control of hypertension are the highest in the world. Nonindustrialized countries can decisively control CVD. PMID:16317211

  11. The Cuban Missile Crisis: Evolving Historical Perspectives.

    ERIC Educational Resources Information Center

    Medland, William J.

    1990-01-01

    Presents a synthesis of the views of participants and counterviews of scholars concerning the Cuban missile crisis of 1962. Reviews historical and analytical accounts of the crisis. Describes critical areas of conflicting interpretations by historians and participants. Includes an annotated bibliography of teaching resources. (NL)

  12. The Cuban Missile Crisis. Lesson Plan.

    ERIC Educational Resources Information Center

    Miller, Linda K.; McAuliffe, Mary

    1994-01-01

    Presents a secondary lesson plan based on primary sources recently released by the Central Intelligence Agency on the Cuban Missile Crisis. Provides a background essay on the event. Includes five maps and three documents, all of which have been declassified from top secret or secret status. (CFR)

  13. The Foreign Policy of Angola under Agostinho Neto

    DTIC Science & Technology

    1983-12-01

    Angolan conflict soon entangled the sideline actors South Africa and SVAPO. An evaluation of the prevailing political and ethnic dynamics in southern...forces, with Soviet arms and Cuban troops, quickly sought to squash the Ovimbundu-based liberation movement. A series of Cuban-led offensives routed

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

    PubMed

    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 (<68% with grade A). Resort beaches and those with international visitors showed the best litter management. 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.

  15. The Impact of Cuban Economic Reform on Older Persons.

    PubMed

    Strug, David L

    2017-03-01

    This paper discusses the economic reforms initiated by Cuban President Raúl Castro in 2008 and its effect on the country's fast-growing, vulnerable population of older persons 60+ years of age. Cubans are living longer and the country has a very low birthrate. These two factors combined have reduced the proportion of the population in the work force. This adversely affects the economy. Population aging is a major reason why the government has introduced structural reforms and reduced social spending, which have weakened the welfare state on which older persons depend. Many older persons have become critical of the reforms over time. Policy makers need to address the impact the reforms are having on older Cubans and consider them as active participants in economic reform. Data for this paper come from qualitative, case study research carried out in Havana between the years 2008-15 and from a review of the literature on aging and economic reforms in Cuba. Two case studies illustrate the impact of the economic reforms on older persons.

  16. Construction of a novel Mo/Cu/S cluster with a closed double-cubane-like polyhedron and a chain polymer of W/Cu/S clusters.

    PubMed

    Li, Zhihua; Du, Shaowu; Wu, Xintao

    2004-08-09

    Reaction of [MoOS(3)](2)(-) and [WS(4)](2)(-) with Cudtp (dtp = diethyl dithiophosphate) gave rise to the clusters [Bu(4)N](2)[(MoOS(3))(4)Cu(12)(dtp)(6)], 1, and [Et(4)N][(WS(4)Cu(4))(dtp)(3)], 2, respectively. In cluster 1, the dtp- ligands act as both monodentate and bidentate ligands that bridge between Cu atoms and link together a closed double-cubane-like [Mo(2)O(2)S(6)Cu(6)](2+) core and two incomplete cubane-like [MoOS(3)Cu(3)]+ units. In cluster 2, the [WS(4)Cu(4)](2+) fragments were connected via bidentate and doubly bridging dtp- bridges to give a chain polymeric anion. Cluster 1 is the first example of a Mo/Cu/S cluster that contains a closed double-cubane-like structure. Compound 2 is also rare and the first W/Cu/S polymer with dtp- linkages.

  17. 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.

    PubMed

    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).

  18. Glimpses of Biological Research and Education in Cuba.

    ERIC Educational Resources Information Center

    Margulis, Lynn; Kunz, Thomas H.

    1984-01-01

    Discusses Cuban medical facilities, biological research (focusing on sugarcane tissue culture, interferon, hybrid cattle, tropical fruits, and yeast biosynthetic pathways), science education programs at all levels, and institutions of higher education. Also examines such concerns as the Cuban literacy rate and efforts to improve the environment.…

  19. When Fear Ruled: Rethinking the Cuban Missile Crisis.

    ERIC Educational Resources Information Center

    Paterson, Thomas G.

    1995-01-01

    Provides an insightful look at the administrative and negotiative processes that accompanied the 1962 Cuban missile crisis. Although John F. Kennedy and Nikita Khrushchev both worked to avoid nuclear war, the stress and exhaustion of the negotiating process created serious blunders. Eventually both sides backed away from nuclear annihilation. (MJP)

  20. 8 CFR 1212.12 - Parole determinations and revocations respecting Mariel Cubans.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Parole determinations and revocations respecting Mariel Cubans. 1212.12 Section 1212.12 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION...; ADMISSION OF CERTAIN INADMISSIBLE ALIENS; PAROLE § 1212.12 Parole determinations and revocations respecting...

  1. 8 CFR 1212.12 - Parole determinations and revocations respecting Mariel Cubans.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Parole determinations and revocations respecting Mariel Cubans. 1212.12 Section 1212.12 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION...; ADMISSION OF CERTAIN INADMISSIBLE ALIENS; PAROLE § 1212.12 Parole determinations and revocations respecting...

  2. 8 CFR 1212.12 - Parole determinations and revocations respecting Mariel Cubans.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Parole determinations and revocations respecting Mariel Cubans. 1212.12 Section 1212.12 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION...; ADMISSION OF CERTAIN INADMISSIBLE ALIENS; PAROLE § 1212.12 Parole determinations and revocations respecting...

  3. 31 CFR 515.546 - Accounts of Cuban sole proprietorships.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Accounts of Cuban sole proprietorships. 515.546 Section 515.546 Money and Finance: Treasury Regulations Relating to Money and Finance... proprietorships. Specific licenses are issued unblocking sole proprietorships established under the laws of Cuba...

  4. 31 CFR 515.546 - Accounts of Cuban sole proprietorships.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 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... proprietorships. Specific licenses are issued unblocking sole proprietorships established under the laws of Cuba...

  5. 31 CFR 515.546 - Accounts of Cuban sole proprietorships.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Accounts of Cuban sole proprietorships. 515.546 Section 515.546 Money and Finance: Treasury Regulations Relating to Money and Finance... proprietorships. Specific licenses are issued unblocking sole proprietorships established under the laws of Cuba...

  6. 31 CFR 515.546 - Accounts of Cuban sole proprietorships.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Accounts of Cuban sole proprietorships. 515.546 Section 515.546 Money and Finance: Treasury Regulations Relating to Money and Finance... proprietorships. Specific licenses are issued unblocking sole proprietorships established under the laws of Cuba...

  7. 76 FR 31011 - Proposed Collection; Comment Request for Cuban Remittance Affidavit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-27

    ... persons in Cuba pursuant to the general licenses in section 515.570 of the Cuban Assets Control... religious organizations, remittances to students in Cuba pursuant to an educational license, limited... to increase people-to- people contact, support civil society in Cuba, enhance the free flow of...

  8. Cuban Geography in Higher Education: Survival in the "Special Period."

    ERIC Educational Resources Information Center

    Miller, Mark M.; And Others

    1996-01-01

    Provides a concise and interesting overview of the state of higher education in Cuba, specifically focusing on geography. The interests, methodologies, and programs of Cuban geographers are similar to other countries, albeit at a truncated level due to the United States embargo. Discusses international educational exchange efforts. (MJP)

  9. Interactive Videodisc Technology: Applications to the Air Command and Staff College Curriculum.

    DTIC Science & Technology

    1988-04-01

    objectives )r Executive and NSC system Congress Military Intelligence community Media National environment Transcultural communications Global challenges...Cuban missile crisis REGIONAL STUDIES: USSR AND EUROPE Superpower global objectives The Soviet Union: background The Soviet political-economic system...summary National security affairs review The crisis game WARFARE STUDIES MILITARY HISTORY AND THEORY * - Overview to thinking about war Sun Tzu Great

  10. FAILURE OF NUCLEAR DETERRENCE IN THE CUBAN MISSILE CRISIS

    DTIC Science & Technology

    2017-04-06

    performance in executing strategy should be approached. “One must in particular avoid ex post facto judgements: the fairer procedure is to evaluate the...Charles Bartlett. “In Time of Crisis.” The Saturday Evening Post , (8 Dec 1962), 15-20. Barlow, Jeffrey G. “The Cuban Missile Crisis.” In Naval

  11. Anglo-American and Cuban-American Teachers' Perception of Elementary School Boys and Girls.

    ERIC Educational Resources Information Center

    Dempsey, Arthur D.

    The attitudes of Cuban- and Anglo-American elementary school teachers concerning boys and girls were compared. It appears to be generally accepted in Anglo-American culture that males are considered hostile and aggressive in school situations, while females are considered passive and conforming. Conversely, in the Latin American cultures, the…

  12. 31 CFR 515.415 - Travel to Cuba; transportation of certain Cuban nationals.

    Code of Federal Regulations, 2010 CFR

    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...

  13. 31 CFR 515.415 - Travel to Cuba; transportation of certain Cuban nationals.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 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...

  14. Socialist Consciousness Raising and Cuba's School to the Countryside Program

    ERIC Educational Resources Information Center

    Blum, Denise

    2008-01-01

    As a participant-observer, the author relates observations, interviews, and surveys from her experience in a Cuban Escuela al Campo ("School to the Countryside," or EAC) camp located on a collective farm outside of the city of Havana. The Pioneers, the youth section of the official Cuban Communist Party, organize the EAC program…

  15. 31 CFR 515.415 - Travel to Cuba; transportation of certain Cuban nationals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 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...

  16. Grounding Immigrant Generations in History: Cuban Americans and Their Transnational Ties.

    ERIC Educational Resources Information Center

    Eckstein, Susan; Barberia, Lorena

    2002-01-01

    Investigated differences in views and involvements between two cohorts of first generation Cuban-American immigrants. Interviews with immigrants indicated that the first wave left between 1959-1979 mainly for political reasons and publicly opposes travel to Cuba. The second wave immigrated largely for economic reasons and is enmeshed in…

  17. Cuban Voices: A Case Study of English Language Teacher Education

    ERIC Educational Resources Information Center

    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.…

  18. 31 CFR 515.415 - Travel to Cuba; transportation of certain Cuban nationals.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 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...

  19. 31 CFR 515.415 - Travel to Cuba; transportation of certain Cuban nationals.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 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...

  20. Theological Higher Education in Cuba: Part 3--The Cuban Revolution

    ERIC Educational Resources Information Center

    Esqueda, Octavio J.

    2007-01-01

    This article provides a summary of the Cuban Revolution and its implications and consequences for Christian higher education in Cuba. Christian institutions experienced the same oppression from the communist revolution as the rest of the evangelical denominations during the sixties and seventies. The worst period for Protestantism began in 1965…

  1. Race and Place in the Adaptation of Mariel Exiles.

    ERIC Educational Resources Information Center

    Skop, Emily H.

    2001-01-01

    The influx of lower class Cuban emigres during the 1980 Mariel Boatlift complicates the success story image of previous waves of Cuban exiles. Argues that place of incorporation should be a necessary ingredient in illuminating diverse adjustment experiences among immigrants and refugees to the United States. Concludes by discussing the Cuban…

  2. Educational Reform Hyperwaves: Reconceptualizing Cuban's Theories of Change

    ERIC Educational Resources Information Center

    Berkovich, Izhak

    2017-01-01

    The present work builds on Cuban's ("Educ Res" 19(1):3-13, 1990) seminal work on reform waves. The research explores reform waves in Israeli educational policies since 2000s. The historical case study analysis focuses on conservative and liberal-progressive reforms in education, and reveals that these reforms took place as reoccurring…

  3. Insulating an Ideology: The Enclave Effect on South Florida's Cuban Americans

    ERIC Educational Resources Information Center

    Girard, Chris; Grenier, Guillermo J.

    2008-01-01

    Many Cuban Americans embrace a distinctive anti-Castro ideology. Although this ideology supports the embargo against Cuba--purportedly to bring about the Castro regime's compliance or collapse--the real objectives may be more symbolic than practical. Ultimately, the institutional completeness provided by the enclave in South Florida insulates and…

  4. Successful Insurgent Revolutions in Latin America: Analysis of the Cuban and Nicaraguan Revolutions

    DTIC Science & Technology

    2014-03-01

    Thomas H. Greene, Comparative Revolutionary Movements: Search for Theory and Justice, 3rd ed. (Englewood Cliffs, NJ: Prentice- Hall Contemporary...Revolution, Insurgency, Leadership, Popular Support, External Influence, Military, Insurgent Life Cycle, Theories of Revolution, Cuban Revolution, M-26-7...REVOLUTIONS .............................................. 17   A.   THEORIES OF REVOLUTION

  5. Heterometallic appended {MMn(III)4} cubanes encapsulated by lacunary polytungstate ligands.

    PubMed

    Wu, Hai-Hong; Yao, Shuang; Zhang, Zhi-Ming; Li, Yang-Guang; Song, You; Liu, Zhu-Jun; Han, Xin-Bao; Wang, En-Bo

    2013-01-14

    The heterometallic appended {MMn(III)(4)} (M = Dy(3+) and K(+)) cubanes were firstly trapped by two diamagnetic POM shells, which were robust enough to construct inorganic crystalline tubular materials. Magnetic study reveals the presence of a SMM-like slow magnetic relaxation feature in the heterometallic cluster-containing POM.

  6. La Educacion Preescolar en Cuba [Preschool Education in Cuba].

    ERIC Educational Resources Information Center

    Childhood Education, 2002

    2002-01-01

    Describes the "Educate Your Child" program, a Cuban family-based program supported by UNICEF and designed to enhance the total development of children from birth until the start of formal schooling for the 80 percent of Cuban children who do not attend the Children's Circle preschool program. Highlights the importance of the regional…

  7. Language Use and Identity in the Cuban Community in Russia

    ERIC Educational Resources Information Center

    Yakushkina, Maria; Olson, Daniel J.

    2017-01-01

    A significant body of research has begun to explore the association between language and identity, a relationship that becomes more complex when considering multilingual communities. Important for this field, a number of studies have examined the interrelation between language and identity in the Cuban population in the USA, a case in which…

  8. The Cuban-American Counterpoint: Black Cubans in the United States.

    ERIC Educational Resources Information Center

    Dixon, Heriberto

    The term "Hispanics" as currently used in the United States is a gross oversimplification of the reality of a highly heterogeneous people. Among the many important variables that divide and subdivide the Hispanic population into distinctive and significant subpopulations are race, language, time of arrival in the United States, national origin,…

  9. Sociocultural Adaptations among Cuban Emigre Women in Miami, Florida.

    ERIC Educational Resources Information Center

    Gonzalez, Diana H.

    This paper reports on Cuban women living in Miami (Florida) and their adaptation to life in exile. It includes an examination of health care practices, particularly the practice of self-diagnosis and self-prescription of minor tranquilizers as coping behaviors for dealing with acculturation and culture shock. Data were gathered from questionnaires…

  10. Tampa's Splendid Little War: Local History and the Cuban War of Independence.

    ERIC Educational Resources Information Center

    Mormino, Gary R.

    1998-01-01

    Presents a look at the local culture of Tampa, Florida at the turn of the century and how it responded to a massive influx of troops waiting for action during the Spanish-American War. At that time, Tampa was a multiethnic city that included many Cuban-, Spanish-, and African-Americans. (MJP)

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

    NASA Astrophysics Data System (ADS)

    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.

  12. The Organization of Mental Health Services in Cuba.

    ERIC Educational Resources Information Center

    Camayd-Freixas, Yohel; Uriarte, Miren

    1980-01-01

    Reviews the status and organization of the Cuban mental health system. Focuses on the deliberate and systematic interdependence of mental health, public health, and socio-political structures; inpatient treatment modes and rehabilitation programs; use of social networks to support discharged patients; community-based care; and primary to tertiary…

  13. SOME NOTES ON CUBAN TRADITIONAL MEDICINE

    PubMed Central

    Santana, Refal Milanes

    1996-01-01

    The traditional medical system of cuba is an amalgam so the medical knowledge of the Africans, Hispanics and the Amerindians of cuba. An attempt is made is this article to provide a short introduction to this fascinating body of knowledge, which awaits further investigations by scholars of ethnic medicine. PMID:22556768

  14. 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.

    PubMed

    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 previously reported double cubanes of higher charge. Trigonally symmetric single cubanes eliminate isomers in the formation of double cubanes and other cluster structures, and may be of considerable value in the preparation of new types of M-Fe-S clusters. (Tpms = tris(pyrazolyl)methanesulfonate(1-); Tp = hydrotris(pyrazolyl)borate(1-).)

  15. 31 CFR 515.505 - Certain Cuban nationals unblocked; transactions of certain other Cuban nationals lawfully present...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... nationals who have taken up permanent residence outside of Cuba. 515.505 Section 515.505 Money and Finance... residence outside of Cuba. (a) General license unblocking certain persons. The following persons are... national; and (2) Any entity that otherwise would be a national of Cuba solely because of the interest...

  16. 31 CFR 515.505 - Certain Cuban nationals unblocked; transactions of certain other Cuban nationals lawfully present...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... nationals who have taken up permanent residence outside of Cuba. 515.505 Section 515.505 Money and Finance... residence outside of Cuba. (a) General license unblocking certain persons. The following persons are... national; and (2) Any entity that otherwise would be a national of Cuba solely because of the interest...

  17. 31 CFR 515.505 - Certain Cuban nationals unblocked; transactions of certain other Cuban nationals lawfully present...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... nationals who have taken up permanent residence outside of Cuba. 515.505 Section 515.505 Money and Finance... residence outside of Cuba. (a) General license unblocking certain persons. The following persons are... national; and (2) Any entity that otherwise would be a national of Cuba solely because of the interest...

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

    ERIC Educational Resources Information Center

    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…

  19. 31 CFR 515.505 - Certain Cuban nationals unblocked; transactions of certain other Cuban nationals lawfully present...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... nationals who have taken up permanent residence outside of Cuba. 515.505 Section 515.505 Money and Finance... residence outside of Cuba. (a) General license unblocking certain persons. The following persons are... national; and (2) Any entity that otherwise would be a national of Cuba solely because of the interest...

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

    DTIC Science & Technology

    1988-12-01

    find in Cuba. The visitors even brought parts for old American automobiles on their flights to Cuba. People wore several layers of clothing, peeling ...2,000 PRESSURE FOR MIGRATION 399IJ! goa ,q AP Wide World Photos Cuban farmers sell bananas and garlic at a small "peasant market" in Havana on 19

  1. Structure and Spontaneity: Pedagogical Tensions in the Construction of a Simulation of the Cuban Missile Crisis.

    ERIC Educational Resources Information Center

    Pace, David; And Others

    1990-01-01

    Describes a 5-day simulation workshop on the Cuban Missile Crisis developed for 60 secondary school students participating in the Indiana University summer gifted and talented program. Uses role playing and game situations to teach critical thinking. Finds these techniques effective in providing a sense of power and competence. (NL)

  2. Outcomes of Various Scaffolding Strategies on Student Teachers' Digital Historical Inquiries

    ERIC Educational Resources Information Center

    Lee, John K.; Molebash, Philip E.

    2004-01-01

    In this study, 30 students in a graduate level social studies methods course used digital historical resources to respond to a single question about the Cuban Missile Crisis: "How was the Cuban Missile Crisis resolved?" The participants were placed in three groups and each group was given a different scaffolding strategy for using online sources…

  3. 31 CFR 515.512 - Provision of certain legal services authorized.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... authorized. (a) The provision of the following legal services to or on behalf of Cuba or a Cuban national is... services to Cuba or a Cuban national, not otherwise authorized in this part, requires the issuance of a... other judicial process purporting to transfer or otherwise alter or affect property in which Cuba or a...

  4. Cuban Women, Sex Role Conflicts and Use of Prescription Drugs.

    ERIC Educational Resources Information Center

    Gonzalez, Diana H.; Page, J. Brian

    This paper focuses on Cuban women migrants living in Miami (Florida) and on their adaptation to life in exile, especially their use of minor tranquilizers. Many of these women left Cuba for political and economic reasons. The migration process restructured their social status in many ways. They were not allowed to bring valuables or financial…

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

    PubMed

    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.

  6. The Effects of Looping in the Cuban Classroom: Teacher Perception and Academic Achievement

    ERIC Educational Resources Information Center

    Pickett, Gabriela

    2016-01-01

    The system of public education in the United States lacks responsiveness to differing maturation rates and learning styles of young children. U.S. public education focuses more on satisfying governmental mandates and a common curriculum measured through standardized tests than on addressing the individual learning needs of each student.…

  7. Ofelia Rodríguez Acosta and the Quest for National Solidarity in Cuba

    ERIC Educational Resources Information Center

    Ortiz-Loyola, Brenda

    2015-01-01

    By the mid-1920s, the feminist movement was gaining strong support within Cuban society, at the same time that Cubans were growing discontent with the repression and corruption of Gerardo Machado's dictatorial regime. Within this context, women writers like Ofelia Rodríguez Acosta fused the feminist fight for women's rights with a nationalist…

  8. Teaching History Then and Now: A Story of Stability and Change in Schools

    ERIC Educational Resources Information Center

    Cuban, Larry

    2016-01-01

    In "Teaching History Then and Now," Larry Cuban explores the teaching of history in American high schools during the past half-century. Drawing on his early career experience as a high school history educator and his more recent work as a historian of US education policy and practice, Cuban examines how determined reformers have and have…

  9. Cuban Youth Culture and Receding Futures: Hip Hop, Reggaetón and "Pedagogías Marginal"

    ERIC Educational Resources Information Center

    Dixon-Román, Ezekiel; Gomez, Wilfredo

    2012-01-01

    Cuba finds itself at the centre of various discourses yet again, as publications such as "The Economist" and others debate the future of Cuban culture and society. While issues of economics, ideology and politics are fertile ground for discussion, they do not encompass the totality of such a conversation. The authors argue that critical…

  10. Cuban/US Research Interactions Since 1995

    NASA Astrophysics Data System (ADS)

    Tamargo, Maria C.

    Interactions between Cuban physicists and researchers in the United States are difficult, to say the least. The complexities associated with communication and travel between Cuba and the US greatly hamper these efforts. Nevertheless, scientific interactions are permitted within the limits of the US embargo, and travel to Cuba to attend international scientific conferences or for well-documented research and educational purposes is allowed.

  11. The Experiences of Cuban American Women Attending a Hispanic Serving Institution and the Influences on Identity Development

    ERIC Educational Resources Information Center

    Owles, Veronica

    2009-01-01

    The purpose of this study was to gain an understanding and gather insight into the experiences of Cuban American women attending a 4-year, public, Hispanic Serving Institution and how those experiences influenced their identity development. This was accomplished by conducting in-depth interviews and focus groups with 12 self-identified Cuban…

  12. Case Report: Cutaneous Leishmaniasis in Cuban Immigrants to Texas who Traveled through the Darién Jungle, Panama

    PubMed Central

    Barry, Meagan A.; Koshelev, Misha V.; Sun, Grace S.; Grekin, Sarah J.; Stager, Charles E.; Diwan, A. Hafeez; Wasko, Carina A.; Murray, Kristy O.; Woc-Colburn, Laila

    2014-01-01

    Cutaneous leishmaniasis is rarely seen in the United States. Four Cuban immigrants traveled along the same route at different times from Cuba to Ecuador, then northward, including through the Darién Jungle in Panama. These patients had chronic ulcerative non-healing skin lesions and were given a diagnosis of leishmaniasis. PMID:24865687

  13. 31 CFR 515.555 - Assets of Cuban firms wholly or substantially owned by U.S. citizens.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...; and, (5) Satisfactory proof that such stock was owned by U.S. citizens as of July 8, 1963. Such proof... substantially owned by U.S. citizens. 515.555 Section 515.555 Money and Finance: Treasury Regulations Relating... of Cuban firms wholly or substantially owned by U.S. citizens. (a) Specific licenses are issued to...

  14. 31 CFR 515.555 - Assets of Cuban firms wholly or substantially owned by U.S. citizens.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...; and, (5) Satisfactory proof that such stock was owned by U.S. citizens as of July 8, 1963. Such proof... substantially owned by U.S. citizens. 515.555 Section 515.555 Money and Finance: Treasury Regulations Relating... of Cuban firms wholly or substantially owned by U.S. citizens. (a) Specific licenses are issued to...

  15. 31 CFR 515.555 - Assets of Cuban firms wholly or substantially owned by U.S. citizens.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...; and, (5) Satisfactory proof that such stock was owned by U.S. citizens as of July 8, 1963. Such proof... substantially owned by U.S. citizens. 515.555 Section 515.555 Money and Finance: Treasury Regulations Relating... of Cuban firms wholly or substantially owned by U.S. citizens. (a) Specific licenses are issued to...

  16. 31 CFR 515.555 - Assets of Cuban firms wholly or substantially owned by U.S. citizens.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...; and, (5) Satisfactory proof that such stock was owned by U.S. citizens as of July 8, 1963. Such proof... substantially owned by U.S. citizens. 515.555 Section 515.555 Money and Finance: Treasury Regulations Relating... of Cuban firms wholly or substantially owned by U.S. citizens. (a) Specific licenses are issued to...

  17. 31 CFR 515.555 - Assets of Cuban firms wholly or substantially owned by U.S. citizens.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...; and, (5) Satisfactory proof that such stock was owned by U.S. citizens as of July 8, 1963. Such proof... substantially owned by U.S. citizens. 515.555 Section 515.555 Money and Finance: Treasury Regulations Relating... of Cuban firms wholly or substantially owned by U.S. citizens. (a) Specific licenses are issued to...

  18. Cubans in the United States: A Bibliography for Research in the Social and Behavioral Sciences, 1960-1983. Bibliographies and Indexes in Sociology, Number 1.

    ERIC Educational Resources Information Center

    MacCorkle, Lyn, Comp.

    This volume brings together a wide-ranging body of English-language sources pertaining to Cuban American society. Some 1,600 references cite journal and periodical articles, dissertations, government reports, conference papers, and unpublished works. Spanish-language bibliographies that contain English-language titles or related Spanish-language…

  19. Synthetic control and empirical prediction of redox potentials for Co 4O 4 cubanes over a 1.4 V range: implications for catalyst design and evaluation of high-valent intermediates in water oxidation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nguyen, Andy I.; Wang, Jianing; Levine, Daniel S.

    The oxo-cobalt cubane unit [Co 4O 4] is of interest as a homogeneous oxygen-evolution reaction (OER) catalyst, and as a functional mimic of heterogeneous cobalt oxide OER catalysts. The synthesis of several new cubanes allows evaluation of redox potentials for the [Co 4O 4] cluster, which are highly sensitive to the ligand environment and span a remarkable range of 1.42 V. The [Co III 4O 4] 4+/[Co III 3Co IVO 4 ]5+ and [Co III 3Co IVO 4] 5+/[Co III 2Co IV 2O 4] 6+ redox potentials are reliably predicted by the pKas of the ligands. Hydrogen bonding is alsomore » shown to significantly raise the redox potentials, by ~500 mV. The potential-p K a correlation is used to evaluate the feasibility of various proposed OER catalytic intermediates, including high-valent Co-oxo species. The synthetic methods and structure–reactivity relationships developed by these studies should better guide the design of new cubane-based OER catalysts.« less

  20. Promoting Scientific Cooperation in Times of Diplomatic Challenges: Sustained Partnership between the Cuban Academy of Sciences and the American Association for the Advancement of Science.

    PubMed

    Jorge-Pastrana, Sergio; Gual-Soler, Marga; Wang, Tom C

    2018-04-01

    Scientific research cooperation between Cuba and the USA has a long history that dates back to the 19th century. For the past 200 years, the two countries' relationship has been subject to complex economic, political and social forces. In the second half of the 20th century, the Cuban revolution and the subsequent escalation of the US government embargo impacted every aspect of Cuban life. While science was no exception, scientific interactions never ceased. Over the past decade, scientific cooperation-led and facilitated by scientific organizations such as the Cuban Academy of Sciences, the American Association for the Advancement of Science and others-has steadily increased to address ever more critical issues facing both countries. Science and global health diplomacy were key to reestablishing a trusting and productive relationship of mutual and global benefit after the USA and Cuba restored diplomatic relations in 2015. However, recent changes in Cuba policy by the new US administration are jeopardizing these opportunities for increased scientific cooperation, which are in the best interests of people in both countries. KEYWORDS International cooperation, academies and institutes, Cuba, USA.

  1. Is greater acculturation associated with an increased prevalence of cardiovascular risk factors among Latinos in South Florida?

    PubMed

    Chang, Aileen; Kenya, Sonjia; Ilangovan, Kumar; Li, Hua; Koru-Sengul, Tulay; Alonzo, Yisel; Carrasquillo, Olveen

    2015-05-01

    To examine the association of acculturation with various cardiovascular risk factors (CRFs) among Latinos with diabetes in South Florida. In a cross-sectional analysis of data collected from 300 Latinos with poorly controlled diabetes we measured acculturation using the Marin Short Acculturation Scale. We examined correlations between acculturation and the following 7 CRFs: hemoglobin A1C, low-density lipoprotein, systolic blood pressure, body mass index, smoking status, physical activity, and fruit and vegetable intake. Cubans made up 38% of our population; no other Latino subgroup represented over 17% of the sample. Of the 8 outcomes examined, only smoking was associated with increased acculturation; 12% of Latinos in the 2 lowest acculturation groups were current smokers versus 25% in the highest acculturation group (P=0.02). Furthermore, Cuban Americans from our sample had over double the prevalence of smoking compared with non-Cubans in both the lowest and highest acculturation groups. With the exception of smoking, our data does not support a link between increased acculturation and higher prevalence of CRFs in Latinos with diabetes. Smoking prevention and cessation programs targeting Latinos and particularly among Cubans are needed.

  2. Synthetic control and empirical prediction of redox potentials for Co 4O 4 cubanes over a 1.4 V range: implications for catalyst design and evaluation of high-valent intermediates in water oxidation

    DOE PAGES

    Nguyen, Andy I.; Wang, Jianing; Levine, Daniel S.; ...

    2017-04-07

    The oxo-cobalt cubane unit [Co 4O 4] is of interest as a homogeneous oxygen-evolution reaction (OER) catalyst, and as a functional mimic of heterogeneous cobalt oxide OER catalysts. The synthesis of several new cubanes allows evaluation of redox potentials for the [Co 4O 4] cluster, which are highly sensitive to the ligand environment and span a remarkable range of 1.42 V. The [Co III 4O 4] 4+/[Co III 3Co IVO 4 ]5+ and [Co III 3Co IVO 4] 5+/[Co III 2Co IV 2O 4] 6+ redox potentials are reliably predicted by the pKas of the ligands. Hydrogen bonding is alsomore » shown to significantly raise the redox potentials, by ~500 mV. The potential-p K a correlation is used to evaluate the feasibility of various proposed OER catalytic intermediates, including high-valent Co-oxo species. The synthetic methods and structure–reactivity relationships developed by these studies should better guide the design of new cubane-based OER catalysts.« less

  3. A review of the genus Berosus Leach of Cuba (Coleoptera, Hydrophilidae)

    PubMed Central

    Deler-Hernández, Albert; Fikáček, Martin; Cala-Riquelme, Franklyn

    2013-01-01

    Abstract The Cuban fauna of the genus Berosus Leach, 1817 is reviewed based on newly collected material as well as historical and type specimens. Nine species are recognized, including three recorded from Cuba for the first time: Berosus infuscatus LeConte, 1855, Berosus interstitialis Knisch, 1924 (= Berosus stribalus Orchymont, 1946 syn. n.) and Berosus metalliceps Sharp, 1882. Only one of the nine Cuban species, Berosus chevrolati, remains endemic to Cuba, as two other species previously considered as endemic to Cuba are recorded from elsewhere: Berosus quadridens from Mexico and Central America and Berosus trilobus from the Dominican Republic. Notes on biology and Cuban distribution are provided for all nine species. Berosus quadridens Chevrolat, 1863, stat. restit. is removed from synonym with Berosus truncatipennis and considered a valid species. PMID:23794806

  4. Osteopilus septentrionalis (Cuban treefrog)

    USGS Publications Warehouse

    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.

  5. The Cuban Population of the United States: The Results of the 1980 U.S. Census of Population. Occasional Papers Series, Dialogues #40.

    ERIC Educational Resources Information Center

    Perez, Lisandro

    The principal results of the 1980 United States Census regarding Cuban Americans are summarized and analyzed in this report. The presentation is divided into the following sections: (1) residence and geographic distribution; (2) age and sex composition; (3) fertility; (4) family structure and marital status; (5) educational characteristics; (6)…

  6. The Cuban Model for Higher Education of Older Adults: Generativity, Social Commitment, and Collaborative Work

    ERIC Educational Resources Information Center

    Yuni, José Alberto; Urbano, Claudio Ariel

    2014-01-01

    The present work is an approach to study the "Cuban model" for educating the elderly, and its aim is to describe the main features of the experience developed by this country. The University of the Third Age is more than three decades old in Latin America, but none of the countries in the region can show a state educational policy…

  7. 31 CFR 515.505 - Certain Cuban nationals unblocked; transactions of certain other Cuban nationals lawfully present...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... specially designated national; and (2) Any entity that otherwise would be a national of Cuba solely because... until the individual thereafter becomes domiciled in or a permanent resident of Cuba, meets any of the criteria in § 515.302(a)(2) through (5), or is a “specially designated national” of Cuba, as that term is...

  8. The Hedgehog and the Fox: A Discussion of the Approaches to the Analysis of ICT Reforms in Teacher Education of Larry Cuban and Yrjo Engestrom

    ERIC Educational Resources Information Center

    Rasmussen, Ingvill; Ludvigsen, Sten

    2009-01-01

    This article discusses how to analyze educational reforms in which information and communications technology (ICT) is used as a central catalyst to change practises. We explore the relationship between theoretical conceptualizations and empirical findings drawing on the work of Larry Cuban and Yrjo Engestrom. We claim that reform research has…

  9. Effects of Humanitarian Aid: A Cuban Case Study

    DTIC Science & Technology

    2002-09-01

    are then supported by statements from American students . Dagoberto Rodriguez , the Director of North American Affairs in the Cuban Foreign Ministry... students through their time in the United States and interaction with Americans. • Basic infrastructure : Small medical clinics with refrigeration units...required allies. These allies were needed to donate, subsidize, trade, or loan material resources and assist with training programs to make Cuba more self

  10. Associations between neighborhood socioeconomic environment and physical activity in Cuban immigrants.

    PubMed

    Affuso, Olivia; Singleton, Chelsea R; Brown, Scott C; Perrino, Tatiana; Huang, Shi; Szapocznik, José

    2016-12-01

    Physical inactivity is a major public health concern because it is a determinant of obesity and obesity-related chronic diseases. Few longitudinal studies have examined the association between neighborhood socioeconomic (SES) environment and change in physical activity behaviors. Additionally, few studies have examined this association in immigrant groups or Hispanic subgroups such as Cubans. This research aimed to determine if neighborhood SES is associated with longitudinal change in moderate-to-vigorous physical activity (MVPA) among Cuban immigrants who participate in the Cuban Health Study in Miami, Florida. Data on 280 participants [mean age: 37.4 (± 4.6), 48.9% women, mean body mass index: 25.0 (± 2.5)] collected at baseline, 12 months and 24 months were analyzed. Minutes of MVPA were objectively measured during each data collection period using accelerometers. A neighborhood SES score was calculated for each participant's residential census tract from American Community Survey data on median household income, median housing value, educational attainment and occupation. The neighborhood SES score was grouped into tertiles, reflecting low, moderate and high neighborhood SES environment. Multilevel linear models were used to examine the relationship between neighborhood SES and change in MVPA over 24 months. At baseline, 94 (33.6%), 108 (38.6%) and 78 (27.9%) participants resided in low, moderate, and high SES neighborhoods, respectively. After adjusting for age, sex, and body mass index, no difference in average change in MVPA over time was observed between participants residing in low and moderate SES neighborhoods ( p =0.48) or low and high SES neighborhoods ( p =0.62). In Cuban immigrants, longitudinal change in MVPA may not vary by neighborhood socioeconomic environment.

  11. Inflammatory bowel disease is presenting sooner after immigration in more recent US immigrants from Cuba.

    PubMed

    Damas, O M; Avalos, D J; Palacio, A M; Gomez, L; Quintero, M A; Deshpande, A R; Sussman, D A; McCauley, J L; Lopez, J; Schwartz, S J; Abreu, M T

    2017-08-01

    Despite a rising incidence of inflammatory bowel disease (IBD) in Hispanics in the United States, there are no studies examining the relationship between immigrant generation and IBD onset among Hispanics. To determine whether age of IBD diagnosis, time from immigration to IBD diagnosis and IBD phenotype, differed across immigration periods in South Florida Cuban immigrants. This was a cohort of consecutively identified Cuban-born adults who developed IBD in the United States and were followed in gastroenterology (GI) clinic. We divided time cohorts of immigration by historical relevance: before 1980, 1980-1994 and 1995-to-present. We examined differences across time cohorts in diagnosis age, time from immigration to IBD diagnosis, and IBD phenotype (ie, IBD type, disease location). A total of 130 Cuban patients with IBD were included. Age of IBD diagnosis was older in Cubans arriving before 1980 than in those arriving between 1980-1994 or after 1995 (44.7 vs 33.79 and 33.71, respectively, P<.0001). Time between immigration and diagnosis was shorter in patients arriving to the US after 1980 (31.77 years, Standard deviation (SD) 12.83 (<1980) vs 17.13 years, SD 8.55 (1980-1994) and 8.30 years, SD 4.72 (1995-to-present). IBD phenotype, including type of IBD, disease location and surgeries, did not differ significantly across time cohorts. Our study describes changing patterns of IBD onset following immigration in Cubans, suggesting that environmental changes either in the United States, Cuba or both are resulting in faster IBD onset in younger immigrant generations. These studies can inform the search for environmental triggers that may result in IBD. © 2017 John Wiley & Sons Ltd.

  12. Revolution and Intervention: U.S.-Cuban Relations in the 20th Century. SSEC American History Series.

    ERIC Educational Resources Information Center

    Tegnell, Geoffrey; Ladenburg, Thomas

    This unit for U.S. history courses examines a number of questions raised by U.S.-Cuban relations beginning with the Spanish-American War of 1898 and ending with the missile crisis 64 years later. These questions are on such topics as the appropriate U.S. stance toward a nationalistic reform movement, a social revolution, and a military build up in…

  13. Economic and Security Reasons Why the U.S. Should Normalize Relations with Cuba

    DTIC Science & Technology

    2008-06-01

    45 “Overview of Cuban Business Environment.” 27 Table 2. Active International Economic...reveals the depth and variety of Cuba’s FDI. By the end of 2000, the approximately 400 joint ventures in business in Cuba by the end of 2000...47 “Cuba Facts.” 48 “Overview of Cuban Business Environment.” 0 500 1000 1500 2000 2500 1993 1994 1995

  14. Cutaneous leishmaniasis in Cuban immigrants to Texas who traveled through the Darién Jungle, Panama.

    PubMed

    Barry, Meagan A; Koshelev, Misha V; Sun, Grace S; Grekin, Sarah J; Stager, Charles E; Diwan, A Hafeez; Wasko, Carina A; Murray, Kristy O; Woc-Colburn, Laila

    2014-08-01

    Cutaneous leishmaniasis is rarely seen in the United States. Four Cuban immigrants traveled along the same route at different times from Cuba to Ecuador, then northward, including through the Darién Jungle in Panama. These patients had chronic ulcerative non-healing skin lesions and were given a diagnosis of leishmaniasis. © The American Society of Tropical Medicine and Hygiene.

  15. The Physics of Complex Systems in Cuba

    NASA Astrophysics Data System (ADS)

    Sotolongo-Costa, Oscar

    In relating the circumstances that led to the birth and development of the physics of complex systems in Cuba, it is difficult to avoid being anecdotal—particularly because of the difficult times during which this research started. Cuban eclecticism, whose spectrum extends from religious syncretism to world-class medicine, seems quite coherent with the field of complex systems, characterized by the synergy of diverse fields. Such a combination, however, in the beginning seemed to be quite removed from the physicists' standard research dogmas.

  16. The Soviet-Cuban Connection in Central America and the Caribbean

    DTIC Science & Technology

    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

  17. Use of Selected Drugs among Hispanics: Mexican-Americans, Puerto Ricans, and Cuban-Americans. Findings from the Hispanic Health and Nutrition Examination Survey.

    ERIC Educational Resources Information Center

    CSR, Inc., Washington, DC.

    As part of the Hispanic Health and Nutrition Examination Survey (1982-84), prevalences of marijuana, cocaine, inhalant, and sedative use were examined among Hispanic Americans, aged 12-74. This report analyzes data on 3,394 Mexican-Americans in the Southwest, 1,286 Puerto Ricans in the New York City area, and 555 Cuban-Americans in the Miami area,…

  18. Recent Trends and Future Prospects of Terrorism in the United States

    DTIC Science & Technology

    1988-05-01

    34 violence. Two Puerto Rican terror- ist groups, the Comandos Armados de Liberacion (Armed Commandos of Liberation) and the Movimiento de Independencia...Cuban Nationalist Movement, the FLNC (Frente de Liberacion Nacional Cubana, or Cuban National Liberation Front), and Omega-7. 11 12 RECENT TRENDS AND...island. Most of this activity has been carried out by either the FALN (Fuerzas Armadas de Liberacion Nacional, or Armed Forces of the National

  19. In Search of the Missing Link: Relating Destruction to Outcome In Airpower Application

    DTIC Science & Technology

    1994-06-01

    thereafter.� See Graham T . Allison, �The Cuban Missile Crisis: A Case Study of Crisis Decision-making,� American Defense Policy, eds. John F. Reichart...Books: Allison, Graham T . Essence of Decision. Harvard: Harper Collins, 1971. _________. �The Cuban Missile Crisis: A Case Study of Crisis...adversary�s economic and military power. The vulnerability of an adversary�s transportation is based on the fact that transportation networks

  20. Effects of prescribed fire on conditions inside a Cuban parrot (Amazona Leucocephala) surrogate nesting cavity on Great Abaco, Bahamas

    Treesearch

    Joseph O' Brien; Caroline Stahala; Gina P. Mori; Mac Callaham; Chris M. Bergh

    2006-01-01

    Cuban Parrots (Amazona leucocephala) on the island of Great Abaco in the Bahamas forage and nest in native pine forests. The population is unique in that the birds nest in limestone solution holes on the forest floor. Bahamian pine forests are fire-dependent with a frequent surface fire regime. The effects of fire on the parrots, especially while nesting, are not well...

  1. Post Castro Cuba: An Opportunity for Normalized Cuban-American Relations

    DTIC Science & Technology

    1990-05-01

    required for economic growth. Consequently, diversification of the industrial base was absent. Investors had grown content in maintaining assets in cash...construction of a naval base at Guantanamo Bay. (5:45-46) Although countries such as Mexico, Argentina, and Brazil took important steps toward industrial ...classes of people, which served to unite Cubans regardless of their political persuasions. In the name of "la revolucion ", its force and being could

  2. 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

    USGS Publications Warehouse

    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.

  3. Scientific Cooperation Between the German Academy of Sciences in Berlin (DAW) and Cuba in the 1960s and 1970s

    NASA Astrophysics Data System (ADS)

    Wendt, Helge

    After the ratification of its constitution in 1959, the young Cuban Republic sought new cooperation partners in a number of different fields. One of these fields was scientific cooperation. It seems the Cubans quickly found partners in the academies of science of the USSR, Czechoslovakia and China, whereas the German Academy of Sciences in Berlin (DAW) was reluctant to engage in long-term cooperative projects. In the early 1960s, the universities of East Germany (GDR) began to send docents and scientists to Cuba where they participated in the summer schools, taught for one semester or more in one of the universities and undertook research that would be useful for their home institutions. However, the DAW carefully observed the reestablishment of Cuba's own academy of science before becoming involved in common projects with Cuban partners.

  4. October Surprises.

    PubMed

    2016-10-01

    Ushered in with the rampage of Hurricane Matthew, later days brightened in this month that has often been harbinger of both good and bad news for Cuba and the world. Hurricane Matthew ripped through Eastern Cuba, devastating the historic town of Baracoa (Cuba's first capital, founded in 1511) and the village of Maisí, where the morning sun first rises over Cuban territory. Wind and flood leveled hundreds of homes, brought down the power grid and destroyed crops. Yet there was no loss of human life, unlike in neighboring Haiti and other countries in Matthew's path, and unlike in Cuba in 1963, when Hurricane Flora caused more than 1200 deaths. In Haiti, efforts of health workers-including hundreds of Haitian graduates from Cuba's Latin American Medical School and 600 Cuban health professionals already there-were bolstered by dozens of specially trained Cuban disaster medical personnel in the wake of the storm.

  5. Education in Cuba--An Alternative Educational Discourse: Lessons to Be Learned?

    ERIC Educational Resources Information Center

    Breidlid, Anders

    2007-01-01

    This article focuses on the Cuban education system, which is well known for its focus on inclusion and equality of opportunity, but also for its focus on political and ideological conformity. The economic crisis in Cuba has led to an educational crisis as well, both in terms of teacher shortages and a decrease in quality and in…

  6. Argumentation in the Canadian House of Commons on the Issue of Nuclear Weapons for Canada.

    ERIC Educational Resources Information Center

    Jones, John Alfred

    The Cuban missile crisis of October 1962 forced the Canadian House of Commons to consider whether Canadian forces in NORAD and NATO were effective without nuclear warheads on special weapons systems. This paper provides an overview of the debates and their milieu, identifies the issues involved, and analyzes the effects of the argumentation. The…

  7. Homeland Security in Absentia: Policing Miami in the Era of the New U.S.- Cuba Relationship

    DTIC Science & Technology

    2017-03-01

    relationship between power and choice. A study published in Psychological Science noted, “ people are willing to trade one source of control for the other...heavily Cuban- American dominated community. The political influence of Cubans in Miami became evident by 1985, when they represented the majority... people . b. Political Since 1991, the United Nations has overwhelmingly condemned the U.S. embargo against Cuba, with Israel being the sole American

  8. Oral Testimony from the Hispanic Community of Greater Boston; Programa Para el Desarrollo de un Curriculo Universitario en Estudios Etnicos Puertorriquenos y Cubanos (Program for the Development of a University Curriculum in Puerto Rican and Cuban Ethnic Studies).

    ERIC Educational Resources Information Center

    Forbes, Robert J., Ed.

    The oral testimony presented in this document was designed to supplement materials, strategies, and recommendations contained in "Guidelines for the Development of a Program in Puerto Rican and Cuban Ethnic Heritage Studies at the Post-Secondary Level" (Curry College, 1976). Part 1, "The Hispanic Media," consists of interviews…

  9. Hypertension, poor glycemic control, and microalbuminuria in Cuban Americans with type 2 diabetes.

    PubMed

    Zarini, Gustavo G; Exebio, Joel C; Gundupalli, Deva; Nath, Subrata; Huffman, Fatma G

    2011-01-01

    To investigate to what degree the presence of hypertension (HTN) and poor glycemic control (GC) influences the likelihood of having microalbuminuria (MAU) among Cuban Americans with type 2 diabetes (T2D). A cross-sectional study conducted in Cuban Americans (n = 179) with T2D. Participants were recruited from a randomly generated mailing list purchased from Knowledge-Base Marketing, Inc. Blood pressure (BP) was measured twice and averaged using an adult size cuff. Glycosylated hemoglobin (A1c) levels were measured from whole blood samples with the Roche Tina-quant method. First morning urine samples were collected from each participant to determine MAU by a semiquantitative assay (ImmunoDip). MAU was present in 26% of Cuban Americans with T2D. A significantly higher percentage of subjects with MA had HTN (P = 0.038) and elevated A1C (P = 0.002) than those with normoalbuminuria. Logistic regression analysis showed that after controlling for covariates, subjects with poor GC were 6.76 times more likely to have MAU if they had hypertension compared with those without hypertension (P = 0.004; 95% confidence interval [CI]: 1.83, 23.05). The clinical significance of these findings emphasizes the early detection of MAU in this Hispanic subgroup combined with BP and good GC, which are fundamentals in preventing and treating diabetes complications and improving individuals' renal and cardiovascular outcomes.

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

    PubMed

    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.

  11. Citrate, in collaboration with a guanidinium ion, as a generator of cubane-like complexes with a range of metal cations: synthesis, structures, and magnetic properties of [C(NH2)3]8[(M(II))4(cit)4].8H2O (M = Mg, Mn, Fe, Co, Ni, and Zn; cit = Citrate).

    PubMed

    Hudson, Timothy A; Berry, Kevin J; Moubaraki, Boujemaa; Murray, Keith S; Robson, Richard

    2006-05-01

    Aqueous reaction mixtures containing citric acid, guanidinium carbonate, and a range of metal cations (Mg2+, Mn2+, Fe2+, Co2+, Ni2+, and Zn2+) at room temperature give crystalline products of composition [C(NH2)3]8[(M(II))4(cit)4].8H2O (cit = citrate). In all cases, the crystals are suitable for single-crystal X-ray diffraction studies, which reveal that the compounds are isostructural (space group P4(2)/n; a approximately 16.2 A, and c approximately 11.5 A). As was intended, cubane-like [M4(cit)4]8- complex anions are present. The individual citrate units are chiral, but each cubane unit contains two of one hand and two of the other, related around an S4 axis. The cubane units are involved in no less than 40 H-bonding interactions with guanidinium cations and lattice water molecules. Detailed susceptibility and magnetization studies show that the intracluster magnetic coupling within the Mn(II), Fe(II), Co(II), and Ni(II) cubanes is very weak in all cases with J values of -0.82, -0.43, and -0.09 cm(-1) for the Mn, Fe, and Co species, respectively. A two-J model gave the best agreement with the susceptibility and high-field magnetization data for the Ni(II) case, over the whole temperature range studied, and the sign of the parameters, J12 = -0.3 cm(-1) and J13 = +2.97 cm(-1), correlated with the two Ni-(mu3-O)-Ni angles observed in the cluster structure. All members of the 3d-block [M4(cit)4]8- family have spin ground states, ST, of zero, with the higher ST levels just a few reciprocal centimeters away in energy.

  12. Epidemic optic neuropathy in Cuba. Eye findings.

    PubMed

    Sadun, A A; Martone, J F; Muci-Mendoza, R; Reyes, L; DuBois, L; Silva, J C; Roman, G; Caballero, B

    1994-05-01

    To characterize and establish a clinical definition of the optic neuropathy that appeared in epidemic form in Cuba in 1992 and 1993. At the invitation of the Cuban Ministry of Health, Havana, members of ORBIS International and the Pan American Health Organization, assembled teams that traveled to Cuba in May 1993. We were initially briefed by Cuban national experts in the areas of virology, nutrition, toxicology, ophthalmology, neurology, and public health. We then examined 20 patients on our own. Thirteen of these patients underwent a comprehensive neuro-ophthalmologic examination, including neurologic examination, ophthalmologic examination, visual fields, optic nerve function studies, contrast sensitivity studies, and funduscopy. We returned 4 months later to perform an additional 12 comprehensive neuro-ophthalmologic and follow-up examinations. Only seven of the 13 patients who were alleged to have the optic form of the epidemic and who were rigorously and systematically examined on the first visit demonstrated a bilateral optic neuropathy. These seven patients had several features that included decreased visual acuity, poor color vision, central scotomas, decreased contrast sensitivity, saccadic eye movements, and most prominent and distinctive of all, nerve fiber layer wedge defects of the papillomacular bundle. Our clinical definition was then implemented by the Cuban ophthalmologists and epidemiologists. On returning 4 months later, we found that all newly presented patients were correctly diagnosed to have the epidemic disease. With the new case definition and the application of a few simple psychophysical tests, the false-positive rate of diagnosis became much lower. After vitamin therapy, we reexamined the patients seen on our initial visit, and all showed marked improvement. The Cuban epidemic was characterized by an optic neuropathy with features that were similar to those of tobacco/alcohol amblyopia and Leber's optic atrophy. Recent political, economic, and social changes in Cuba may have contributed to the nutritional and/or toxic compromise of mitochondrial function of an acquired nature, which led to selective retinal ganglion cell damage. We have termed this condition Cuban epidemic optic neuropathy.

  13. Canada’s Prime Ministers and the Nuclear Weapons Venture, from Uncle Louis to Dief, 1948 to 1963

    DTIC Science & Technology

    2016-06-10

    21 A Soviet bomb ... bombs that ended the Second World War. Twenty years later, just about every major weapon system in the arsenal of the Canadian Armed Forces (CAF) had...Maloney, Learning To Love The Bomb (Washington, DC: Potomac Books, 2007), 323-357. 2 Ibid., 343-349. 3 Peter T. Haydon, The 1962 Cuban Missile Crisis

  14. ADDRESSING THE DEFICIT: Updating the Budgetary Implications of Selected GAO Work

    DTIC Science & Technology

    1996-06-01

    DGPS DI DLA DOD DOE DOT DUR EDWAA EM EPA FAIR FAA FAS FDIC FHWA FY GAO GSA HACCP HCFA HHS HMO HUD IDB IFAD INS IRS JCT...Marti, the broadcasts are constantly and effectively jammed , USIA’S research data shows that, mainly as a result of the jamming , the number of Cubans...hours (from 3:30 am to 8:00 am), but Cuban jamming also expanded. In an attempt to overcome jamming , TV Marti has plans to convert from VHF to UHF

  15. Use of Naval Force in Crises: A Theory of Stratified Crisis Interaction. Volume 2

    DTIC Science & Technology

    1988-12-01

    commanders were a little too enthusias- tic, and we had 4 bad crashes and lost 3 pilots before I got them slowed down. I have to get some of these carriers off...Admiral’s Memoir," The Washington Quarterly, Autumn 1982, p. 86. Vice Admiral Houser, Naval Assistant to Roswell Gilpatric during the crisis, states "I... crashing over or near Cuba (causing speculation that the Cubans shot them down), and Cuban Komar missile boats or coastal defense missile sites

  16. La Naturaleza del Estado Cubano y el Llamado a La Inversion Extranjera: Crisis o Invitacion al Cambio (The Nature of the Cuban State and the Call for Foreign Investment: Crisis or Invitation to Change).

    ERIC Educational Resources Information Center

    Campbell, Luis E. Hartly

    1995-01-01

    Presents a study of the period of crisis in modern Cuba dating back to 1991. An overview of the Cuban character is given in order to promote understanding of the environment that has permitted the present socialist government to remain in power since 1959. It is concluded that Cuba requires massive foreign investment in every sector for its…

  17. Hispanic Subgroups, Acculturation, and Substance Abuse Treatment Outcomes

    PubMed Central

    Chartier, Karen G.; Carmody, Tom; Akhtar, Maleeha; Stebbins, Mary B.; Walters, Scott T.; Warden, Diane

    2015-01-01

    This study explored Hispanic subgroup differences in substance use treatment outcomes, and the relationship of acculturation characteristics to these outcomes. Data were from a multisite randomized clinical trial of motivational enhancement therapy versus treatment as usual in a sample of Spanish-speaking substance abusers. Participants were Cuban American (n=34), Mexican American (n=209), Puerto Rican (n=78), and other Hispanic American (n=54). Results suggested that Cuban Americans and individuals with more connection to Hispanic culture had lower treatment retention. Hispanics born in the U.S and those who spoke English at home had a lower percentage of days abstinent during weeks 5-16, although Puerto Ricans born in the U.S. and Cuban Americans living more years in the U.S. had a higher percentage of days abstinent in weeks 1-4 and 5-16, respectively. Results may inform future hypothesis-driven studies in larger Hispanic treatment seeking samples of the relationship between acculturation and treatment outcome. PMID:26362001

  18. Consequences of sea level variability and sea level rise for Cuban territory

    NASA Astrophysics Data System (ADS)

    Hernández, M.; Martínez, C. A.; Marzo, O.

    2015-03-01

    The objective of the present paper was to determine a first approximation of coastal zone flooding by 2100, taking into account the more persistent processes of sea level variability and non-accelerated linear sea level rise estimation to assess the main impacts. The annual linear rate of mean sea level rise in the Cuban archipelago, obtained from the longest tide gauge records, has fluctuated between 0.005 cm/year at Casilda and 0.214 cm/year at Siboney. The main sea level rise effects for the Cuban coastal zone due to climate change and global warming are shown. Monthly and annual mean sea level anomalies, some of which are similar to or higher than the mean sea level rise estimated for halfway through the present century, reinforce the inland seawater penetration due to the semi-daily high tide. The combination of these different events will result in the loss of goods and services, and require expensive investments for adaption.

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

    PubMed

    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.

  20. Diabetes-related risk factors across Hispanic subgroups in the Hispanic health and nutritional examination survey (1982-1984).

    PubMed

    Aponte, Judith

    2009-01-01

    The Hispanic Health and Nutritional Examination Survey (HHANES) was utilized to examine diabetes-related risk factor variables between and among 3 Hispanic subgroups. The study design that was conducted was descriptive using the HHANES secondary data set. The sample included individuals between 20 and 74 years of age, self-identified as Mexican American, Puerto Rican, and/or Cuban American and had been told by a doctor that they had diabetes. The 5 diabetes-related risk factor variables were obesity measured by body mass index (BMI), hypertension by systolic blood pressure (SBP) and diastolic blood pressure (DBP), hyperlipidemia by cholesterol and triglyceride levels, renal insufficiency by blood urea nitrogen (BUN), and creatinine and fasting plasma glucose. This study demonstrates significant differences between specific subgroups through chi-square. SBP in Cuban Americans was significantly higher than that of Puerto Ricans (28.39 mmHg) and of Mexican Americans (25.94 mmHg). Cuban Americans also had significantly higher cholesterol values than Mexican Americans (88.49 mg/dL) and Puerto Ricans (84.49 mg/dL). The only significant difference for triglyceride was between Mexican Americans and Puerto Ricans (37.25 mg/dL). For BUN, there were significant differences when Cuban Americans (9.06 mg/dL) and Mexican Americans (2.20 mg/dL) were separately compared from Puerto Ricans, and Cuban Americans had significantly higher creatinine values than Puerto Ricans (0.38 mg/dL) and Mexican Americans (0.25 mg/dL). Through linear regression, significant differences for the association of each diabetes-related risk factor and the risk for diabetes complications were computed for each subgroup. For Mexican Americans and Puerto Ricans there were significant differences in overweight BMI (25.0-29.9 kg/m2) and obesity (> or =30.0 kg/m2); for Mexican Americans, Puerto Ricans and Cuban Americans in elevated SBP (130-139 mmHg) or elevated DBP (80-89 mmHg), for high SBP (> or =140 mmHg) or high DBP (> or =90 mmHg), and for high glucose (> or =126 mg/dL); and for Mexican Americans in elevated triglyceride (> or =150 mg/dL), elevated BUN (> or =21 mg/dL), and elevated creatinine (> or =1.5 mg/dL). The findings of this study will add to the diabetes and Hispanic literature highlighting the need to evaluate Hispanic subgroups in future health behavior and outcomes research.

  1. Oncology nursing in Cuba: report of the delegation.

    PubMed

    Sheldon, Lisa Kennedy; Leonard, Kathleen; Gross, Anne; Hartnett, Erin; Poage, Ellen; Squires, Jennifer; Ullemeyer, Vicki; Schueller, Mary; Stary, Susan; Miller, Mary Alice

    2012-08-01

    In December 2011, the first delegation of oncology nurses from the United States visited Havana, Cuba. The delegation included oncology nurses, educators, and leaders from across America and provided opportunities to learn about the healthcare system, cancer, and oncology nursing in Cuba. Delegation members attended lectures, toured facilities, and enjoyed Cuban culture. This exchange highlighted the similarities in cancer care and oncology nursing between countries and opened doors for future collaborations.

  2. Strategy for Enlisting Lateral Entrants Via Computer Technology (SELECT): An Automated System for Determining Rating and Pay Grade Qualification for Potential Navy Lateral Entry Accessions

    DTIC Science & Technology

    1983-09-01

    Filipino (6- ) Mexican American/Chicano (7: ) Eskimo (8- ) Aleut (9: ) Cuban American (D- ) India (E’ ) Malaysian (G ) Chinese (J" 1...INTERNSHIP PHOTOGRAPHY/ CINEMA (2,2,3,3); FILM PRODUCTION (0,2,3,3); PORTRAITURE (0,1,1,1); TECH PHOTOGRAPHY (0,0,1,2); PERSNNEL SUPERVISION (0,0,1,3

  3. Heisenberg model of a {Cr8}-cubane magnetic molecule

    NASA Astrophysics Data System (ADS)

    Luban, Marshall; Kögerler, Paul; Miller, Lance L.; Winpenny, Richard E. P.

    2003-05-01

    A Heisenberg model of eight CrIII paramagnetic centers (spins s=3/2) at the vertices of a cube with four distinct exchange interactions is found to provide a reasonably accurate description of the magnetic susceptibility of the cubane-type magnetic molecule [Cr8O4(O2CC6H5)16]={Cr8} from 2-290 K for an external field of 0.5 T. We find that two exchange bonds are antiferromagnetic (13, 24 K) and two are ferromagnetic (5, 13.5 K), with an accuracy of approximately 1 K. The determination of the four exchange constants is greatly facilitated using the exact high-temperature expansion of the weak-field susceptibility, effectively reducing the number of unknown parameters to two. We have calculated the thermodynamic properties of the system and these can be compared with the results of future experiments. At temperatures below 0.5 K sharp increases are expected in the magnetization versus external magnetic field at approximately 6 and 12 T and higher fields due to level crossings. Inelastic neutron scattering could check our predictions for the low-lying magnetic energy levels.

  4. The Effective Use of U.S. Coast Guard Security Zones in Countering Unlawful Transnational Protests at Sea

    DTIC Science & Technology

    2009-01-01

    Clinton’s Cuba Policy, August 1994," Presidential Studies Quarterly 28, no. 1, Winter 1998, 215. 24 The Sinking ofthe ൕ de Marzo " Tugboat on 13 July...seeking to bring attention to their cause with extreme measures.23 The sinking ofTREZE DE MARZO became an incident on which to focus future protests...Before the mass migration and subsequent agreement of 1994, Cuban migrants hijacked the Cuban tug TREZE DE MARZO on July 11, 1994 in an attempt to escape

  5. Accomplishments in Cuban Physics (up to 1995)

    NASA Astrophysics Data System (ADS)

    Handy, Carlos R.; Trallero-Giner, Carlos

    In late October 1995, one of the authors (CRH) paid a personal visit to Cuba. While there, he took advantage of a longstanding invitation to present a research seminar to the Cuban Physics Society. With respect to the development of physics in Cuba, curiosity led to subsequent visits to various centers including the University of Havana (UH), the Pedagogical Institute, the Institute for Nuclear Science and Technology (INST), the Institute for Cybernetics, Mathematics, and Physics (ICIMAF), the Polytechnic Institute (ISPJAE), the Neuroscience Center, and the National Center for Scientific Research (CNIC).

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

    NASA Astrophysics Data System (ADS)

    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.

  7. JPRS Report, Latin America, Reference Aid. Cuba: Cuban Government Proceedings Against Arnaldo Ochoa Sanchez and Other Officials

    DTIC Science & Technology

    1989-07-25

    citizen gave me musical equipment. When he gave me the equipment, I reported this and asked what I should do with the equipment. I was told to receive...been approved for us. We were going to purchase a yacht to sell to the INTUR [National Institute of Tourism ] which was also a way to cover-up these...Ochoa] In tourism . We were going to invest money in tourism activities. That is why we talked with CUBA- NACAN [expansion unknown; a Cuban enterprise to

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Paul, Aparup; Bertolasi, Valerio; Figuerola, Albert

    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 cubanemore » 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} = S{sub 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{sub 1} = g{sub 2} =2.20, g{sub 3} = g{sub 4} =2.18, J{sub 1} =−36 cm{sup -1}, J{sub 2} =−44 cm{sup -1} and J{sub 3} =0 cm{sup -1}. - Graphical abstract: Tetranuclear Cu(II) complexes with face-sharing-dicubane / double-open-cubane like core frameworks were synthesized and characterized by crystal structure and magnetic analysis. Variable temperature magnetic properties corroborate with their structural arrangement. - Highlights: • Novel tetranuclear copper(II) complexes have been structurally characterized. • Complexes possess face-sharing dicubane/double open cubane core structures. • Variable temperature magnetic measurements reveal antiferromagnetic coupling. • PHI program was used to explain the observed magnetic properties.« less

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

    NASA Astrophysics Data System (ADS)

    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.

  10. Framework fluxionality of organometallic oxides: synthesis, crystal structure, EXAFS, and DFT studies on [[Ru(eta6-arene)]4Mo4O16] complexes.

    PubMed

    Laurencin, Danielle; Garcia Fidalgo, Eva; Villanneau, Richard; Villain, Françoise; Herson, Patrick; Pacifico, Jessica; Stoeckli-Evans, Helen; Bénard, Marc; Rohmer, Marie-Madeleine; Süss-Fink, Georg; Proust, Anna

    2004-01-05

    Reactions of the molybdates Na(2)MoO4.2 H2O and (nBu(4)N)2[Mo2O7] with [[Ru(arene)Cl(2)](2)] (arene=C(6)H5CH3, 1,3,5-C6H3(CH3)(3), 1,2,4,5-C6H2(CH3)4) in water or organic solvents led to formation of the triple-cubane organometallic oxides [[Ru(eta(6)-arene)](4)Mo4O16], whose crystal and molecular structures were determined. Refluxing triple cubane [[Ru(eta(6)-C6H5CH3)](4)Mo4O16] in methanol caused partial isomerization to the windmill form. The two isomers of [[Ru(eta(6)-C6H5CH3)](4)Mo4O16] were characterized by Raman and Mo K-edge X-ray absorption spectroscopy (XAS), both in the solid-state and in solution. This triple-cubane isomer was also used as a spectroscopic model to account for isomerization of the p-cymene windmill [[Ru(eta(6)-1,4-CH3C6H4CH(CH3)2)](4)Mo4O16] in solution. Using both Raman and XAS techniques, we were then able to determine the ratio between the windmill and triple-cubane isomers in dichloromethane and in chloroform. Density functional calculations on [[Ru(eta(6)-arene)](4)Mo4O16] (arene=C6H6, C6H5CH3, 1,3,5-C6H3(CH3)3, 1,4-CH3C6H4CH(CH3)2, C6(CH3)6) suggest that the windmill form is intrinsically more stable, provided the complexes are assumed to be isolated. Intramolecular electrostatic interactions and steric bulk induced by substituted arenes were found to modulate but not to reverse the energy difference between the isomers. The stability of the triple-cubane isomers should therefore be accounted for by effects of the surroundings that induce a shift in the energy balance between both forms.

  11. Learning together: a Canada-Cuba research collaboration to improve the sustainable management of environmental health risks.

    PubMed

    Spiegel, Jerry; Garcia, Maricel; Bonet, Mariano; Yassi, Annalee

    2006-01-01

    To build a national Cuban capacity for training environmental health professionals directly linked to the needs of policy-makers and communities. The University of Manitoba and University of British Columbia collaborated with an established training centre in Cuba (the Instituto Nacional de Higiene y Epidemiologia--INHEM) and new centres in the Central (Santa Clara) and Eastern (Santiago) regions of the country. Cuba. In the mid-1990s, a comprehensive curriculum (masters and diploma programs) was collaboratively developed, applying interactive teaching methods, and was delivered through a series of workshops and other interactions in Cuba, and short-term visits to Canada by Cuban PhD students. The collaboration was successful in fulfilling capacity-building targets (over 50 Masters graduates, 467 Diploma graduates, over 30 trained core faculty in all regional centres as well as new curriculum and new accredited regional programs). Alongside this, a number of collaborative community-based research projects were undertaken in all three regions (drinking water in Santiago; housing and urban renewal, and dengue control in Havana; and tourism-related effects, and effective intersectoral management of population health determinants in Santa Clara). The collaboration led to adopting new strategies for challenges such as a dengue epidemic in 2002, and new research on the effectiveness of intersectoral management of risks of particular interest to both Cuban and Canadian policy-makers. It triggered an ambitious collaboration between the Canadian-Cuban team and colleagues in Ecuador in order to build a similar national network there, built on South-South and North-South links.

  12. Creole - Leninism: Grenada: A Case Study.

    DTIC Science & Technology

    1984-12-01

    18]. The Reagan administration maintained that a 9,000 foot runway was not needed for tourism and was but a ruse for a Soviet and Cuban joint use...next door in Trinidad, where the forces of Fascism are about to take control and the Trinidadians need assistance. Why should we oppose anybody passing...Quadafii gave the Bishop regime three Soviet patrol boats. North Korea provided personnel to construct an irrigation system. Venezuela donated housing

  13. War Termination Concepts and Political, Economic and Military Targeting

    DTIC Science & Technology

    1978-03-01

    imposed by the level of military technology, also served to reduce the probability of transcultural conflict; thus shared value systems probably...from the Berlin Blockade in 1948 through the Cuban Missile Crisis , and, utilizing the "lessons learned" approach, reformulates deterrence theory on...aspect of which is the "general crisis of capitalism," presently said to be in its most severe phase since the 1930s. The present crisis , Soviet

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

    PubMed

    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.

  15. Reactive Pendant Mn═O in a Synthetic Structural Model of a Proposed S4 State in the Photosynthetic Oxygen Evolving Complex.

    PubMed

    Vaddypally, Shivaiah; Kondaveeti, Sandeep K; Karki, Santosh; Van Vliet, Megan M; Levis, Robert J; Zdilla, Michael J

    2017-04-05

    The molecular mechanism of the Oxygen Evolving Center of photosystem II has been under debate for decades. One frequently cited proposal is the nucleophilic attack by water hydroxide on a pendant Mn═O moiety, though no chemical example of this reactivity at a manganese cubane cluster has been reported. We describe here the preparation, characterization, and a reactivity study of a synthetic manganese cubane cluster with a pendant manganese-oxo moiety. Reaction of this cluster with alkenes results in oxygen and hydrogen atom transfer reactions to form alcohol- and ketone-based oxygen-containing products. Nitrene transfer from core imides is negligible. The inorganic product is a cluster identical to the precursor, but with the pendant Mn═O moiety replaced by a hydrogen abstracted from the organic substrate, and is isolated in quantitative yield. 18 O and 2 H isotopic labeling studies confirm the transfer of atoms between the cluster and the organic substrate. The results suggest that the core cubane structure of this model compound remains intact, and that the pendant Mn═O moiety is preferentially reactive.

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

    PubMed Central

    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

  17. The gift of health: Socialist medical practice and shifting material and moral economies in post-Soviet Cuba.

    PubMed

    Andaya, Elise

    2009-12-01

    Drawing on ethnographic data collected over 13 months of fieldwork in family doctor clinics in Havana from 2004 to 2005, I examine the shifting moral and material economies of Cuban socialist medical practice. In both official ideology and in daily practice, the moral economy of ideal socialist medicine is based on an ethos of reciprocal social exchange-that is, the gift-that informs not only doctors' relationships with the Cuban state and with individual patients but also the state's policies of international medical service to developing nations. The social and economic upheavals after the fall of t Soviet Union, however, have compelled both the state and individual doctors to operate in a new local and global economy. The gift remains the central metaphor of Cuban medical practice. Nonetheless, as ideologies and practices of gifting and reciprocity encounter an emerging market economy, gifts--whether on the level of the state policies of international humanism or in patient-doctor relations--are open to new significations that highlight the shifting material and moral economies of post-Soviet Cuba.

  18. Cuba Country Analysis Brief

    EIA Publications

    2016-01-01

    Cuba imports the majority of their energy needs, but offshore oil and gas potential could help mitigate their reliance imports. Cuba has entered into many agreements with various countries to help with exploration and drilling efforts. As a result of the ongoing U.S. trade embargo against Cuba, U.S. companies are unable to own any Cuban oil assets. However, U.S. oil companies are allowed to participate in drilling as well as sending technology and supplies with an executive license. While there is interest in Cuban offshore assets, the combination of low oil prices and technically challenging fields could be stumbling blocks for foreign investment.

  19. Coxsackievirus A6 and enterovirus 71 causing hand, foot and mouth disease in Cuba, 2011-2013.

    PubMed

    Fonseca, Magilé C; Sarmiento, Luis; Resik, Sonia; Martínez, Yenisleidys; Hung, Lai Heng; Morier, Luis; Piñón, Alexander; Valdéz, Odalys; Kourí, Vivian; González, Guelsys

    2014-09-01

    Hand, foot and mouth disease (HFMD) is usually caused by coxsackievirus A16 or enterovirus 71 (EV71). Between 2011 and 2013, HFMD cases were reported from different Cuban provinces. A total of 42 clinical specimens were obtained from 23 patients. Detection, identification and phylogenetic analysis of enterovirus-associated HFMD were carried out by virus isolation, specific enterovirus PCR and partial VP1 sequences. HEV was detected in 11 HFMD cases. Emerging genetic variants of coxsackievirus A6 and EV71 were identified as the causative agents of the Cuban HFMD cases.

  20. Assimilating South African medical students trained in Cuba into the South African medical education system: reflections from an identity perspective.

    PubMed

    Donda, B M; Hift, R J; Singaram, V S

    2016-10-24

    In terms of the Nelson Mandela Fidel Castro Medical Collaboration programme, an agreement between the governments of South Africa and Cuba, cohorts of South African students receive their initial five years medical training at a Cuban university before returning to South Africa for a six to twelve months orientation before integration into the local final year class. It is common for these students to experience academic difficulty on their return. Frequently this is viewed merely as a matter of a knowledge deficit. We argue that the problem arises from a fundamental divergence in the outcomes of the Cuban and South African medical curricula, each of which is designed with a particular healthcare system in mind. Using the discrepancy theory of identity proposed by Higgins in 1987, we discuss the challenges experienced by the returning Nelson Mandela Fidel Castro Medical Collaboration students in terms of a potential crisis of identity and suggest interventions which may prove valuable in promoting academic success and successful integration. Though providing additional training to address the gap in skills and knowledge in returning students is an important part of their successful reintegration, this could be insufficient on its own and must be complemented by a range of measures designed to ameliorate the discrepancies in identity which arise from the transition from one educational model to another.

  1. DNA barcoding of Cuban freshwater fishes: evidence for cryptic species and taxonomic conflicts.

    PubMed

    Lara, Ariagna; Ponce de León, José Luis; Rodríguez, Rodet; Casane, Didier; Côté, Guillaume; Bernatchez, Louis; García-Machado, Erik

    2010-05-01

    Despite ongoing efforts to protect species and ecosystems in Cuba, habitat degradation, overuse and introduction of alien species have posed serious challenges to native freshwater fish species. In spite of the accumulated knowledge on the systematics of this freshwater ichthyofauna, recent results suggested that we are far from having a complete picture of the Cuban freshwater fish diversity. It is estimated that 40% of freshwater Cuban fish are endemic; however, this number may be even higher. Partial sequences (652 bp) of the mitochondrial gene COI (cytochrome c oxidase subunit I) were used to barcode 126 individuals, representing 27 taxonomically recognized species in 17 genera and 10 families. Analysis was based on Kimura 2-parameter genetic distances, and for four genera a character-based analysis (population aggregation analysis) was also used. The mean conspecific, congeneric and confamiliar genetic distances were 0.6%, 9.1% and 20.2% respectively. Molecular species identification was in concordance with current taxonomical classification in 96.4% of cases, and based on the neighbour-joining trees, in all but one instance, members of a given genera clustered within the same clade. Within the genus Gambusia, genetic divergence analysis suggests that there may be at least four cryptic species. In contrast, low genetic divergence and a lack of diagnostic sites suggest that Rivulus insulaepinorum may be conspecific with Rivulus cylindraceus. Distance and character-based analysis were completely concordant, suggesting that they complement species identification. Overall, the results evidenced the usefulness of the DNA barcodes for cataloguing Cuban freshwater fish species and for identifying those groups that deserve further taxonomic attention. © 2009 Blackwell Publishing Ltd.

  2. Novel techniques and insights into the deployment of pop-up satellite archival tags on a small-bodied deep-water chondrichthyan

    NASA Astrophysics Data System (ADS)

    Shipley, Oliver N.; Howey, Lucy A.; Tolentino, Emily R.; Jordan, Lance K. B.; Brooks, Edward J.

    2017-01-01

    Acquiring movement data for small-bodied, deep-water chondrichthyans is challenged by extreme effects of capture and handling stress, and post-release predation, however, it is urgently required to examine important fisheries interactions and assess the ecological role of these species within deep-water food webs. Here we suggest a novel release-cage mechanism to deploy pop-up satellite archival tags, as well as present vertical habitat data for a data-deficient, small-bodied, deep-water bycatch species, the Cuban dogfish (Squalus cubensis). Data were gathered from seven of eight High Rate X-Tags deployed on mature Cuban dogfish in the Exuma Sound, The Bahamas. Recovery periods appeared variable between individuals and are likely driven by capture-and-handling stress and tag burden. Application of the cross-correlation function to time-series depth and temperature data indicated three of the seven individuals suffered mortality through predation, which occurred during daytime, and suggests Cuban dogfish may constitute a proportion of deep-water apex predator diet in the Exuma Sound. Two animals were successfully released via a novel release-cage mechanism and displayed either no, or rapid (<15 mins) vertically stationary recovery periods and were not consumed by predators; data for these individuals were recorded for the entire deployment duration (14 days). Vertical habitat data suggests Cuban dogfish are diel-vertical migrators, similar to other deep-water taxa, and exhibit a relatively broad temperature and depth range, which may be driven by preference for specific bathymetric structures. These techniques provide an important first step into acquiring and presenting vertical habitat data for small-bodied, deep-water chondrichthyans, which can be directly applied to fisheries and ecosystem-based management approaches.

  3. Prospective, comprehensive, and effective viral monitoring in Cuban children undergoing solid organ transplantation.

    PubMed

    Kourí, Vivian; Correa, Consuelo; Martínez, Pedro A; Sanchez, Lizet; Alvarez, Alina; González, Grehete; Silverio, César E; Hondal, Norma; Florin, Jose; Pérez, Lourdes; Duran, Diana P; Perez, Yardelis; Cazorla, Nancy; Gonzalez, Dalmaris; Jaime, Juan C; Arencibia, Alberto; Sarduy, Sandra; Pérez, Lissette; Soto, Yudira; González, Mabel; Alvarez, Iliana; Dorticós, Elvira; Marchena, Juan J; Solar, Luis; Acosta, Belsy; Savón, Clara; Hengge, Ulrich

    2014-01-01

    In Cuba, viral monitoring in the post-transplant period was not routinely performed. The aim of this research is to identify the most frequent viruses that affect transplanted Cuban children, by implementing a viral follow-up during the post-transplant period. The study population included all Cuban pediatric patients who underwent solid organ transplantation (SOT) between November 2009 and December 2012. A total of 34 transplanted pediatric patients of kidney (n = 11) and liver (n = 23) were prospectively monitored during a 34-week period for viral DNAemia and DNAuria by simultaneous detection of cytomegalovirus (CMV), Epstein-Barr virus, herpes simplex virus type 1 and 2, varicella zoster virus, human herpesvirus 6, human adenovirus, and polyomaviruses (BKV and JCV) using quantitative real-time polymerase chain reaction (qRT-PCR). Viral genome of at least one virus was detected in 21 of 34 recipients, 18 patients excreted virus in urine while 12 presented DNAemia. CMV (41.2%) and BKV (35.3%) were the most frequent viruses detected during the follow-up. CMV was the virus mainly associated with clinical symptoms and DNAemia. Its excretion in urine (with cut off value of 219 copies/mL) was associated with detection in plasma (p < 0.001); furthermore, CMV viruria was predictive of CMV viremia (OR:8.4, CI:2.4-29.1, p = 0.001). There was no association between high viral load and clinical complications, due to the prompt initiation of preemptive ganciclovir. This comprehensive viral monitoring program effectively prevents the development of critical viral disease, thus urge the implementation of qRT-PCR as routine for viral monitoring of transplanted Cuban organ recipients.

  4. US and Cuban Scientists Forge Collaboration on Arbovirus Research.

    PubMed

    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.

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

    PubMed

    Sierra, Beatriz; Triska, Petr; Soares, Pedro; Garcia, Gissel; Perez, Ana B; Aguirre, Eglys; Oliveira, Marisa; Cavadas, Bruno; Regnault, Béatrice; Alvarez, Mayling; Ruiz, Didye; Samuels, David C; Sakuntabhai, Anavaj; Pereira, Luisa; Guzman, Maria G

    2017-02-01

    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.

  6. Risk of developing invasive breast cancer in Hispanic women: A look across Hispanic subgroups

    PubMed Central

    Banegas, Matthew P.; Leng, Mei; Graubard, Barry I.; Morales, Leo S.

    2012-01-01

    Background Current evidence on breast cancer among US Hispanic women indicates a significant public health threat, although few studies assess the heterogeneity in breast cancer risk among Hispanics of different origin. Methods The 2000 and 2005 National Health Interview Survey (NHIS) Cancer Control Modules were used to examine the Breast Cancer Risk Assessment Tool (BCRAT) 5-year and lifetime risk of invasive breast cancer among Mexican/Mexican-American, Puerto Rican, Cuban/Cuban-American, Dominican (Republic), Central/South American, Other Hispanic and non-Hispanic white (NHW) women aged 35-84 years. Multiple linear regression models were used to compare the BCRAT 5-year and lifetime breast cancer risk between: i) Hispanics and NHWs and ii) Hispanic subgroups. Results Hispanics had significantly lower mean BCRAT 5-year and lifetime breast cancer risk compared to NHWs (p<0.001). Among Hispanic subgroups, Cuban/Cuban-Americans had a higher BCRAT 5-year risk (p<0.05), while Dominicans had a higher lifetime risk (p<0.001), compared to Mexican/Mexican-American women. Approximately, 2.6% of Hispanic women were at high-risk for breast cancer (BCRAT 5-year risk ≥1.67%), ranging from 1.0% of Central/South Americans to 3.7% of Puerto Ricans; few Hispanics (0.2%) had a lifetime risk ≥20.0%. Conclusions Our findings indicate that Hispanics had significantly lower risk of breast cancer, compared to NHWs, though BCRAT risk significantly differed between specific Hispanic subgroups. We provide estimates of the number of US Hispanic women, from six subgroups, who would be eligible for prophylactic breast cancer chemoprevention. Future studies should further investigate the heterogeneity in breast cancer risk and risk factors between Hispanic women of different origins. PMID:23224859

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

    PubMed Central

    Soares, Pedro; Garcia, Gissel; Perez, Ana B.; Aguirre, Eglys; Cavadas, Bruno; Regnault, Béatrice; Alvarez, Mayling; Ruiz, Didye; Guzman, Maria G.

    2017-01-01

    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. PMID:28241052

  8. Presence of the p.L456V polymorphism in Cuban patients clinically diagnosed with Wilson's disease.

    PubMed

    Clark-Feoktistova, Y; Ruenes-Domech, C; García-Bacallao, E F; Roblejo-Balbuena, H; Feoktistova, L; Clark-Feoktistova, I; Jay-Herrera, O; Collazo-Mesa, T

    2018-06-10

    Wilson's disease is characterized by the accumulation of copper in different organs, mainly affecting the liver, brain, and cornea, and is caused by mutations in the ATP7B gene. More than 120 polymorphisms in the ATP7B gene have been reported in the medical literature. The aim of the present study was to identify the conformational changes in the exon 3 region of the ATP7B gene and detect the p.L456V polymorphism in Cuban patients clinically diagnosed with Wilson's disease. A descriptive study was conducted at the Centro Nacional de Genética Médica and the Instituto Nacional de Gastroenterología within the time frame of 2007-2012 and included 105 patients with a clinical diagnosis of Wilson's disease. DNA extraction was performed through the salting-out method and the fragment of interest was amplified using the polymerase chain reaction technique. The conformational shift changes in the exon 3 region and the presence of the p.L456V polymorphism were identified through the Single-Strand Conformation Polymorphism analysis. The so-called b and c conformational shift changes, corresponding to the p.L456V polymorphism in the heterozygous and homozygous states, respectively, were identified. The allelic frequency of the p.L456V polymorphism in the 105 Cuban patients that had a clinical diagnosis of Wilson's disease was 41% and liver-related symptoms were the most frequent in the patients with that polymorphism. The p.L456V polymorphism was identified in 64 Cuban patients clinically diagnosed with Wilson's disease, making future molecular study through indirect methods possible. Copyright © 2018 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

  9. Differences in neighborhood social cohesion and aerobic physical activity by Latino subgroup.

    PubMed

    Murillo, Rosenda; Echeverria, Sandra; Vasquez, Elizabeth

    2016-12-01

    Previous research has examined the role of neighborhood social cohesion in physical activity outcomes; however, less is known about this relationship across Latino subgroups. The purpose of our study was to examine the association between neighborhood social cohesion and aerobic leisure-time physical activity (LTPA) among Latino adults and to determine whether these associations differ by Latino subgroup. We used cross-sectional 2013-2014 National Health Interview Survey (NHIS) data on Latinos originating from 5 countries/regions (i.e., Latinos of Puerto Rican, Mexican/Mexican-American, Cuban/Cuban-American, Dominican and Central or South American origin) aged ≥18 years (n=11,126). Multivariable logistic regression models were used to estimate associations between self-reported neighborhood social cohesion and meeting aerobic LTPA guidelines. Models were adjusted for age, sex, education, and acculturation. We also investigated whether associations varied by Latino subgroup. In adjusted models for all Latino adults, compared with those reporting low social cohesion, individuals who reported high social cohesion (Odds Ratio [OR]: 1.33; 95% Confidence Interval [CI]: 1.17-1.52) were significantly more likely to meet the aerobic physical activity guideline. When stratified by Latino subgroups, among Mexican/Mexicans-Americans (OR: 1.39; 95% CI: 1.16, 1.66) and Cuban/Cuban Americans (OR: 1.73; 95% CI: 1.00, 2.97) high social cohesion was associated with meeting the aerobic activity guideline. Among Dominicans, those who reported medium social cohesion (OR: 0.52, 95% CI: 0.29, 0.93) were less likely to meet the aerobic activity guideline. When examining aerobic physical activity outcomes in the Latino population, the role of neighborhood social cohesion and the variability among Latino subgroups should be considered.

  10. Analog detection for cavity lifetime spectroscopy

    DOEpatents

    Zare, Richard N.; Harb, Charles C.; Paldus, Barbara A.; Spence, Thomas G.

    2001-05-15

    An analog detection system for determining a ring-down rate or decay rate 1/.tau. of an exponentially decaying ring-down beam issuing from a lifetime or ring-down cavity during a ring-down phase. Alternatively, the analog detection system determines a build-up rate of an exponentially growing beam issuing from the cavity during a ring-up phase. The analog system can be employed in continuous wave cavity ring-down spectroscopy (CW CRDS) and pulsed CRDS (P CRDS) arrangements utilizing any type of ring-down cavity including ring-cavities and linear cavities.

  11. Analog detection for cavity lifetime spectroscopy

    DOEpatents

    Zare, Richard N.; Harb, Charles C.; Paldus, Barbara A.; Spence, Thomas G.

    2003-01-01

    An analog detection system for determining a ring-down rate or decay rate 1/.tau. of an exponentially decaying ring-down beam issuing from a lifetime or ring-down cavity during a ring-down phase. Alternatively, the analog detection system determines a build-up rate of an exponentially growing beam issuing from the cavity during a ring-up phase. The analog system can be employed in continuous wave cavity ring-down spectroscopy (CW CRDS) and pulsed CRDS (P CRDS) arrangements utilizing any type of ring-down cavity including ring-cavities and linear cavities.

  12. A New Approach to Health Services and Pharmacy in Cuba.

    PubMed

    Sánchez, Alina M

    2015-12-01

    In December 17, 2014, U.S. President Barack Obama surprised the world by announcing his intention to enter into negotiations aimed at reestablishing diplomatic relations with Cuba. Since then, expectations and interest regarding the health system of that country have increased. This report focuses on the Cuban health and pharmacy systems from a practical and educational standpoint. Pharmaceutical services, strengths, opportunities, and challenges are described. Cuba's new trends toward patient-centered care are analyzed to provide insights for developing pharmaceutical care practice and implementing policies suitable for practice in all health care settings. © 2015 Pharmacotherapy Publications, Inc.

  13. A cost-effectiveness analysis of a program to control rheumatic fever and rheumatic heart disease in Pinar del Rio, Cuba.

    PubMed

    Watkins, David A; Mvundura, Mercy; Nordet, Porfirio; Mayosi, Bongani M

    2015-01-01

    Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) persist in many low- and middle-income countries. To date, the cost-effectiveness of population-based, combined primary and secondary prevention strategies has not been assessed. In the Pinar del Rio province of Cuba, a comprehensive ARF/RHD control program was undertaken over 1986-1996. The present study analyzes the cost-effectiveness of this Cuban program. We developed a decision tree model based on the natural history of ARF/RHD, comparing the costs and effectiveness of the 10-year Cuban program to a "do nothing" approach. Our population of interest was the cohort of children aged 5-24 years resident in Pinar del Rio in 1986. We assessed costs and health outcomes over a lifetime horizon, and we took the healthcare system perspective on costs but did not apply a discount rate. We used epidemiologic, clinical, and direct medical cost inputs that were previously collected for publications on the Cuban program. We estimated health gains as disability-adjusted life years (DALYs) averted using standard approaches developed for the Global Burden of Disease studies. Cost-effectiveness acceptability thresholds were defined by one and three times per capita gross domestic product per DALY averted. We also conducted an uncertainty analysis using Monte Carlo simulations and several scenario analyses exploring the impact of alternative assumptions about the program's effects and costs. We found that, compared to doing nothing, the Cuban program averted 5051 DALYs (1844 per 100,000 school-aged children) and saved $7,848,590 (2010 USD) despite a total program cost of $202,890 over 10 years. In the scenario analyses, the program remained cost saving when a lower level of effectiveness and a reduction in averted years of life lost were assumed. In a worst-case scenario including 20-fold higher costs, the program still had a 100% of being cost-effective and an 85% chance of being cost saving. A 10-year program to control ARF/RHD in Pinar del Rio, Cuba dramatically reduced morbidity and premature mortality in children and young adults and was cost saving. The results of our analysis were robust to higher program costs and more conservative assumptions about the program's effectiveness. It is possible that the program's effectiveness resulted from synergies between primary and secondary prevention strategies. The findings of this study have implications for non-communicable disease policymaking in other resource-limited settings.

  14. Poor management of low birth weight compounds obesity and chronic diseases in Cuba.

    PubMed

    Hernández-Triana, Manuel

    2015-04-01

    The Cuban population exhibits high prevalence of overweight and associated chronic non-communicable diseases, trends that begin in childhood. In addition to factors related to the mother's health, factors contributing to excess weight gain in Cuban children are: reduced prevalence of exclusive breastfeeding of infants up to six months of age, full-term low birth weight infants and nutritional mismanagement of this group, incorrect complementary feeding, obesogenic diet, family history and sedentary lifestyles. Thus, it is important to adopt comprehensive, multisectoral strategies that promote adequate nutrition and weight control. This is particularly important for full-term low birth weight infants, predisposed to body fat storage.

  15. Norway and Cuba Continue Collaborating to Build Capacity to Improve Weather Forecasting

    NASA Astrophysics Data System (ADS)

    Antuña, Juan Carlos; Kalnay, Eugenia; Mesquita, Michel D. S.

    2014-06-01

    The Future of Climate Extremes in the Caribbean Extreme Cuban Climate (XCUBE) project, which is funded by the Norwegian Directorate for Civil Protection as part of an assignment for the Norwegian Ministry of Foreign Affairs to support scientific cooperation between Norway and Cuba, carried out a training workshop on seasonal forecasting, reanalysis data, and weather research and forecasting (WRF). The workshop was a follow-up to the XCUBE workshop conducted in Havana in 2013 and provided Cuban scientists with access to expertise on seasonal forecasting, the WRF model developed by the National Center for Atmospheric Research (NCAR) and the community, data assimilation, and reanalysis.

  16. Havana: A Bike-Friendly City?

    PubMed

    Coyula, Miguel

    2016-07-01

    The abrupt breakup of the USSR and socialist bloc in the early 1990s dealt a devastating blow to the island's economy. Almost overnight, beneficial aid and trade provided by the Council for Mutual Economic Assistance ground to a halt, including 80% of foreign trade previously conducted as barter and sales of 13 million tons of oil per year at preferential prices. When the Cuban economy bottomed out in 1993, oil imports had dropped from 13 to 4 million tons annually. At the time, Cuba depended almost entirely on imported oil and the dramatic decline in imports created massive blackouts, leaving most Cuban homes without electricity 12 hours a day.

  17. An analysis of the growth based on the size and age distributions of the hawksbill sea turtle inhabiting Cuban waters.

    PubMed

    Kobayashi, M

    2000-11-01

    The first costal scute (C 1) collected from 2, 749 hawksbill turtle (Eretmochelys imbricata) captured in Cuban waters in 1993 and 1994 were analyzed to determine their body size and age distributions. The C 1 width (C 1 W) was converted to the straight carapace length (SCL) using a formula, SCL = 4.3527 (C 1 W)0.8484, to examine its body size distribution. The SCL ranged from 51.3 to 96.1 cm with 68.8 cm of mean and 68.6 cm of median. Ages of captured turtles estimated from the C 1 surface patterns were ranged from 3.3 to 61.5 years old with 15.8 years of mean and 14.5 years of median. A growth function of van Bertalanffy, M(t) = A(1-Be-kt), was applied to determine the relationship between the age and body size (SCL). A formula, SCL = 80.4(1 -0.663e-0.118(Age)), was derived and indicated a slowdown in the growth after about 14 years old. The maturation age and the rate of sexually matured Cuban hawksbill turtles were also discussed based on these results.

  18. Kinanthropometric profile of Cuban women Olympic volleyball champions.

    PubMed

    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 p<0.05 as significance threshold. Results were presented in tables and figures. Centers presented greater absolute size and higher average adipose (22.8±1.7 kg) and bone (7.1±0.6 kg) mass. The mean somatotype of all volleyball 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 kinanthropometric profile of Cuban women Olympic volleyball champions was defined by considerable muscular-skeletal development, with a predominantly mesomorphic somatotype and low endomorphy. Height and body composition varied significantly by playing position.

  19. A Pauson-Khand and ring-expansion approach to the aquariane ring system.

    PubMed

    Thornton, Paul D; Burnell, D Jean

    2006-07-20

    [Structure: see text] The carbocyclic ring system of the aquariolide diterpenes has been synthesized by two routes involving a diastereoselective Pauson-Khand reaction and subsequent ring expansion. In one route, a tetracyclic enone was elaborated to generate the nine-membered ring by Grob fragmentation. In the second approach, a spirocyclic tricycle underwent a facile anionic oxy-Cope rearrangement to complete the synthesis of the desired ring system.

  20. Planetary Rings

    NASA Astrophysics Data System (ADS)

    Tiscareno, Matthew S.

    Planetary rings are the only nearby astrophysical disks and the only disks that have been investigated by spacecraft (especially the Cassini spacecraft orbiting Saturn). Although there are significant differences between rings and other disks, chiefly the large planet/ring mass ratio that greatly enhances the flatness of rings (aspect ratios as small as 10- 7), understanding of disks in general can be enhanced by understanding the dynamical processes observed at close range and in real time in planetary rings.We review the known ring systems of the four giant planets, as well as the prospects for ring systems yet to be discovered. We then review planetary rings by type. The A, B, and C rings of Saturn, plus the Cassini Division, comprise our solar system's only dense broad disk and host many phenomena of general application to disks including spiral waves, gap formation, self-gravity wakes, viscous overstability and normal modes, impact clouds, and orbital evolution of embedded moons. Dense narrow rings are found both at Uranus (where they comprise the main rings entirely) and at Saturn (where they are embedded in the broad disk) and are the primary natural laboratory for understanding shepherding and self-stability. Narrow dusty rings, likely generated by embedded source bodies, are surprisingly found to sport azimuthally confined arcs at Neptune, Saturn, and Jupiter. Finally, every known ring system includes a substantial component of diffuse dusty rings.Planetary rings have shown themselves to be useful as detectors of planetary processes around them, including the planetary magnetic field and interplanetary impactors as well as the gravity of nearby perturbing moons. Experimental rings science has made great progress in recent decades, especially numerical simulations of self-gravity wakes and other processes but also laboratory investigations of coefficient of restitution and spectroscopic ground truth. The age of self-sustained ring systems is a matter of debate; formation scenarios are most plausible in the context of the early solar system, while signs of youthfulness indicate at least that rings have never been static phenomena.

  1. Lithium-promoted hydrogenation of carbon dioxide to formates by heterobimetallic hydridozinc alkoxide clusters.

    PubMed

    Merz, Klaus; Moreno, Mariluna; Löffler, Elke; Khodeir, Lamy; Rittermeier, Andre; Fink, Karin; Kotsis, Konstantinos; Muhler, Martin; Driess, Matthias

    2008-01-07

    The remarkably distinct reactivity of hydridozinc heterobimetallic cubanes [(HZnOtBu)4-n(thf LiOtBu)n] 1a-1d towards CO2 is reported--the hydride transfer from Zn-H to CO2 is drastically accelerated in the presence of Li ions in 1b-1d which led to the respective metal formate hydrates; the systems are inspiring models for the selective conversion of water gas into formates on lithium-promoted ZnO supports.

  2. Mechanistic Investigations of Water Oxidation by a Molecular Cobalt Oxide Analogue: Evidence for a Highly Oxidized Intermediate and Exclusive Terminal Oxo Participation.

    PubMed

    Nguyen, Andy I; Ziegler, Micah S; Oña-Burgos, Pascual; Sturzbecher-Hohne, Manuel; Kim, Wooyul; Bellone, Donatela E; Tilley, T Don

    2015-10-14

    Artificial photosynthesis (AP) promises to replace society's dependence on fossil energy resources via conversion of sunlight into sustainable, carbon-neutral fuels. However, large-scale AP implementation remains impeded by a dearth of cheap, efficient catalysts for the oxygen evolution reaction (OER). Cobalt oxide materials can catalyze the OER and are potentially scalable due to the abundance of cobalt in the Earth's crust; unfortunately, the activity of these materials is insufficient for practical AP implementation. Attempts to improve cobalt oxide's activity have been stymied by limited mechanistic understanding that stems from the inherent difficulty of characterizing structure and reactivity at surfaces of heterogeneous materials. While previous studies on cobalt oxide revealed the intermediacy of the unusual Co(IV) oxidation state, much remains unknown, including whether bridging or terminal oxo ligands form O2 and what the relevant oxidation states are. We have addressed these issues by employing a homogeneous model for cobalt oxide, the [Co(III)4] cubane (Co4O4(OAc)4py4, py = pyridine, OAc = acetate), that can be oxidized to the [Co(IV)Co(III)3] state. Upon addition of 1 equiv of sodium hydroxide, the [Co(III)4] cubane is regenerated with stoichiometric formation of O2. Oxygen isotopic labeling experiments demonstrate that the cubane core remains intact during this stoichiometric OER, implying that terminal oxo ligands are responsible for forming O2. The OER is also examined with stopped-flow UV-visible spectroscopy, and its kinetic behavior is modeled, to surprisingly reveal that O2 formation requires disproportionation of the [Co(IV)Co(III)3] state to generate an even higher oxidation state, formally [Co(V)Co(III)3] or [Co(IV)2Co(III)2]. The mechanistic understanding provided by these results should accelerate the development of OER catalysts leading to increasingly efficient AP systems.

  3. A survey of candidate missions to explore Saturn's rings

    NASA Technical Reports Server (NTRS)

    Wells, W. C.; Price, M. J.

    1972-01-01

    The ring system around Saturn is discussed. Exploration of the rings is required for an understanding of their origin and the hazard they represent to spacecraft near Saturn. In addition the rings may provide useful clues to the origin of the solar system. This study examines the problem of ring system exploration and recommends a sequence of missions which will collect the data required.

  4. Report from the Field: Psychological First Aid for Haiti's Storm Orphans.

    PubMed

    Giraldo, Gloria

    2008-07-01

    In 2004, the final death toll in Haiti from Tropical Storm Jeanne was recorded at 3,006; of these, 2,826 in Gonaïves, a city floating in ruins. The road to Gonaïves was washed out, leaving the city and the department of Artibonite cut off for days from the rest of the country. Dr Juan Carlos Ch�vez, who headed the Cuban medical team in Haiti at the time, recalls that 17 Cuban health professionals were working in the area when the storm barrelled through, among the 400 already serving in the country. They were later joined by another 72 doctors, nurses, technicians and engineers sent directly from Cuba.

  5. Grasshoppers, Crickets and Katydids (Insecta: Orthoptera) of Cuba: an annotated checklist.

    PubMed

    Yong, Sheyla; Perez-Gelabert, Daniel E

    2014-07-07

    An annotated list of the Cuban fauna of Orthoptera is presented. For each species we include details of valid names, synonyms, type specimens (type category, sex, locality and depository), geographic distribution and bibliographic references. Clarifying notes are added, as well as comments on the species considered doubtful. A total of 140 species included in 62 genera, 31 subfamilies and 12 families make up the known Cuban fauna of Orthoptera. The family Episactidae, the acridid subfamily Ommatolampidinae with 3 unknown genera, 3 unknown genera of Tettigoniidae (Conocephalinae) and 1 undescribed new genus of Tetrigidae (Cladonotinae) are here recorded for the first time from Cuba. Syntypes are designated for Hygronemobius histrionicus Zayas.

  6. Immunopharmacology 2011: an updated report of clinical achievements and perspectives.

    PubMed

    Landys Chovel, Mario; Perea, Silvio; de los Ángeles Robinson, María; Rodeiro, Idania; Delgado, René; Ochoa, Rolando F; Hernández, Ana María

    2011-11-01

    On 26-30 June 2011 the Cuban Society of Pharmacology organized the Second International Congress on Immunopharmacology (Immunopharmacology 2011), held at the beautiful Convention Centre 'Plaza América' and the Meliá Varadero Hotel, in Varadero beach, Cuba. The main topics of the congress were immunopharmacology (including inflammation, cancer immunotherapy and immunomodulation), neuroimmunology, and the pharmacology of cytochrome P450 and transporters, among other relevant and updated related topics. Immunopharmacology 2011 offered an outstanding scientific program with the active contribution of 90 speakers from 23 foreign countries, as well as more than 170 Cuban researchers from the most important local institutions devoted to the development of immunology and pharmacology sciences.

  7. Electrochemical investigation of [Co4(μ3-O)4(μ-OAc)4(py)4] and peroxides by cyclic voltammetry.

    PubMed

    Clatworthy, Edwin B; Li, Xiaobo; Masters, Anthony F; Maschmeyer, Thomas

    2016-12-13

    Two oxidative redox processes of the neutral cobalt(iii) cubane, [Co 4 (μ 3 -O) 4 (μ-OAc) 4 (py) 4 ], were investigated by cyclic voltammetry at a glassy carbon electrode in acetonitrile. In addition to the first quasi-reversible one-electron oxidation at E 1/2 = 0.283 V vs. Fc 0/+ , a second quasi-reversible one-electron oxidation was observed at E 1/2 = 1.44 V vs. Fc 0/+ . Oxidation at this potential does not facilitate water oxidation. In the presence of tert-butylhydroperoxide the peak current of this second oxidation increases, suggesting oxidation of the peroxide by the doubly oxidised cubane.

  8. Optical heterodyne detection for cavity ring-down spectroscopy

    DOEpatents

    Levenson, Marc D.; Paldus, Barbara A.; Zare, Richard N.

    2000-07-25

    A cavity ring-down system for performing cavity ring-down spectroscopy (CRDS) using optical heterodyne detection of a ring-down wave E.sub.RD during a ring-down phase or a ring-up wave E.sub.RU during a ring up phase. The system sends a local oscillator wave E.sub.LO and a signal wave E.sub.SIGNAL to the cavity, preferably a ring resonator, and derives an interference signal from the combined local oscillator wave E.sub.LO and the ring-down wave E.sub.RD (or ring-up wave E.sub.RU). The local oscillator wave E.sub.LO has a first polarization and the ring-down wave E.sub.RD has a second polarization different from the first polarization. The system has a combining arrangement for combining or overlapping local oscillator wave E.sub.LO and the ring-down wave E.sub.RD at a photodetector, which receives the interference signal and generates a heterodyne current I.sub.H therefrom. Frequency and phase differences between the waves are adjustable.

  9. Dual annular rotating "windowed" nuclear reflector reactor control system

    DOEpatents

    Jacox, Michael G.; Drexler, Robert L.; Hunt, Robert N. M.; Lake, James A.

    1994-01-01

    A nuclear reactor control system is provided in a nuclear reactor having a core operating in the fast neutron energy spectrum where criticality control is achieved by neutron leakage. The control system includes dual annular, rotatable reflector rings. There are two reflector rings: an inner reflector ring and an outer reflector ring. The reflectors are concentrically assembled, surround the reactor core, and each reflector ring includes a plurality of openings. The openings in each ring are capable of being aligned or non-aligned with each other. Independent driving means for each of the annular reflector rings is provided so that reactor criticality can be initiated and controlled by rotation of either reflector ring such that the extent of alignment of the openings in each ring controls the reflection of neutrons from the core.

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

    PubMed

    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.

  11. The composition and structure of planetary rings

    NASA Technical Reports Server (NTRS)

    Burns, J. A.

    1985-01-01

    The properties of planetary ring systems are summarized herein; emphasis is given to the available evidence on their compositions and to their dynamical attributes. Somewhat contaminated water ice makes up the vast expanse of Saturn's rings. Modified methane ice may comprise Uranus' rings while silicates are the likely material of the Jovian ring. Saturn's rings form an elaborate system whose characteristics are still being documented and whose nature is being unravelled following the Voyager flybys. Uranus' nine narrow bands display an intriguing dynamical structure thought to be caused by unseen shephard satellites. Jupiter's ring system is a mere wisp, probably derived as ejecta off hidden parent bodies.

  12. 3d-4f {Co(II)3Ln(OR)4} Cubanes as Bio-Inspired Water Oxidation Catalysts.

    PubMed

    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.

  13. Science and Technology Diplomacy with Cuba

    NASA Astrophysics Data System (ADS)

    Colon, Frances

    President Obama's announcement of U. S. policy change toward Cuba and increased freedom of interaction with the Cuban people opens unprecedented and long-awaited opportunities for the scientific and engineering communities in the U. S. and in Cuba to establish and expand collaborative efforts that will greatly advance U.S. and Cuba science and technology agendas. New rules for export of donated-only items for scientific use will bring researchers closer to the level of their professional peers around the world. Increasing Cubans' access to information will result in greater interactions between scientific communities and enable the sharing of ideas and discoveries that can fuel entrepreneurship on the island. The scientific community has expressed an extraordinary level of interest in the wide range of scientific opportunities that the new policy presents, in collaborating with their Cuban counterparts, and in supporting the development of scientific capacity in Cuba. In response to numerous expressions of interest and inquiries from the scientific community, the Office of the Science and Technology Adviser to the Secretary of State (STAS) has engaged in public outreach to inform the U.S. science and technology community of the implications of the new policy for collaborative research, emerging scientific opportunities, and the standing limitations for engagement with the people of Cuba.

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

    PubMed

    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.

  15. (Un-)bewusste Markenbildung im Tourismus?. Die Inszenierung der kubanischen Revolution

    NASA Astrophysics Data System (ADS)

    Völkening, Niklas

    2017-12-01

    This paper focuses on recent phenomena of touristic staging of the Cuban revolution, embedded in the peculiar situation of Cuba and its progressive establishment as an international tourist destination. It is shown how, by whom and for what reasons this staging occurs. Furthermore, opportunities and risks of this staging will be highlighted. The opening for international tourism during the 1990s aimed at attracting forex to Cuba, as after the decay of the USSR and the COMECON economic aid broke off. Today tourism, described as a "necessary evil" by Fidel Castro, is one of the most important sources of income for both, the Cuban state and its population. To fulfill the expectations of international tourists, which mainly consist of revolutionary symbols and personalities like Che Guevara on the one hand as well as colonial architecture falling to ruins and classic American cars on the other, many actors in Cuban tourism stage these symbols, narratives and practices. By doing so, they contribute to the creation of a distinctive place brand, both intentionally and unintentionally. The intentional dimension of this process aims at fulfilling the expectations of tourists by reproducing certain narratives. At the same time, the actors involved often have limited understanding for their impact on branding processes among tourists.

  16. Radical-scavenging activity, protective effect against lipid peroxidation and mineral contents of monofloral Cuban honeys.

    PubMed

    Alvarez-Suarez, José M; Giampieri, Francesca; Damiani, Elisabetta; Astolfi, Paola; Fattorini, Daniele; Regoli, Francesco; Quiles, José L; Battino, Maurizio

    2012-03-01

    Several monofloral Cuban honeys were analyzed to determine their free radical-scavenging activity and from this the total antioxidant content was estimated. The protective effect against lipid peroxidation in an in vitro model of rat liver homogenates was evaluated and, lastly, the mineral content of the honeys, which can be related to the maintenance of intracellular oxidative balance, was determined. The scavenging capacities against hydroxyl and superoxide radicals were determined using the spin-trapping technique and the hypoxanthine/xanthine oxidase assay, respectively. Lipid peroxidation was evaluated through the production of TBARS and hydroperoxides. All honeys tested showed potential antioxidant activity with Linen vine displaying the highest scavenging capacity towards the DPPH, hydroxyl and superoxide radicals, while the least efficient was Christmas vine honey. Honeys also inhibited, in a concentration-dependent mode, lipid peroxidation in rat liver homogenates, with Linen vine resulting the best while the least effective was Christmas vine honey. The ability to scavenge free radicals and protect against lipid peroxidation may contribute to the ability of certain Cuban honeys to help in preventing/reducing some inflammatory diseases in which oxidative stress is involved. A total of eight minerals were identified and quantified as follows: cadmium, chromium, copper, nickel, iron, manganese, lead, and zinc. Minerals found in higher concentrations were iron, zinc and manganese.

  17. Vitamin A values of wild-caught Cuban tree frogs (Osteopilus septentrionalis) and marine toads (Rhinella marina) in whole body, liver, and serum.

    PubMed

    Sullivan, Kathleen E; Fleming, Greg; Terrell, Scott; Smith, Dustin; Ridgley, Frank; Valdes, Eduardo V

    2014-12-01

    Recent issues surrounding captive amphibians are often nutritionally related problems, such as hypovitaminosis A. Although supplementation of frogs with vitamin A is a topic of investigation, the underlying issue is understanding vitamin A metabolism in amphibian species. To develop a range of "normal" vitamin A concentrations for captive amphibians, baseline vitamin A concentrations must be established in wild amphibian species. In this study, two species, Cuban tree frogs (Osteopilus septentrionalis; n = 59) and marine toads (Rhinella marina; n = 20) were collected from the wild as part of an invasive species control program at Zoo Miami, Miami, Florida. Serum, liver, and whole body samples were analyzed for vitamin A content. The Cuban tree frogs showed higher concentrations on average of vitamin A in serum (82.8 ppb), liver (248.3 IU/g), and whole body (5474.7 IU/kg) samples compared with marine toads (60.1 ppb; 105.3 IU/g; 940.7 IU/kg, respectively), but differences were not significant (P = 0.22). What can be considered "normal" values of vitamin A concentrations across different amphibian species requires further investigation. Although all amphibians collected in this study appeared healthy, a larger sample size of animals, with known health histories and diets, may provide stronger evidence of normal expectations.

  18. Androgynous, Reconfigurable Closed Loop Feedback Controlled Low Impact Docking System With Load Sensing Electromagnetic Capture Ring

    NASA Technical Reports Server (NTRS)

    Lewis, James L. (Inventor); Carroll, Monty B. (Inventor); Morales, Ray H. (Inventor); Le, Thang D. (Inventor)

    2002-01-01

    The present invention relates to a fully androgynous, reconfigurable closed loop feedback controlled low impact docking system with load sensing electromagnetic capture ring. The docking system of the present invention preferably comprises two Docking- assemblies, each docking assembly comprising a load sensing ring having an outer face, one of more electromagnets, one or more load cells coupled to said load sensing ring. The docking assembly further comprises a plurality of actuator arms coupled to said load sensing ring and capable of dynamically adjusting the orientation of said load sensing ring and a reconfigurable closed loop control system capable of analyzing signals originating from said plurality of load cells and of outputting real time control for each of the actuators. The docking assembly of the present invention incorporates an active load sensing system to automatically dynamically adjust the load sensing ring during capture instead of requiring significant force to push and realign the ring.

  19. Virtual Exploration of the Ring Systems Chemical Universe.

    PubMed

    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.

  20. Boomerang Satellites

    NASA Astrophysics Data System (ADS)

    Hesselbrock, Andrew; Minton, David A.

    2017-10-01

    We recently reported that the orbital architecture of the Martian environment allows for material in orbit around the planet to ``cycle'' between orbiting the planet as a ring, or as coherent satellites. Here we generalize our previous analysis to examine several factors that determine whether satellites accreting at the edge of planetary rings will cycle. In order for the orbiting material to cycle, tidal evolution must decrease the semi-major axis of any accreting satellites. In some systems, the density of the ring/satellite material, the surface mass density of the ring, the tidal parameters of the system, and the rotation rate of the primary body contribute to a competition between resonant ring torques and tidal dissipation that prevent this from occurring, either permanently or temporarily. Analyzing these criteria, we examine various bodies in our solar system (such as Saturn, Uranus, and Eris) to identify systems where cycling may occur. We find that a ring-satellite cycle may give rise to the current Uranian ring-satellite system, and suggest that Miranda may have formed from an early, more massive Uranian ring.

  1. Dual annular rotating [open quotes]windowed[close quotes] nuclear reflector reactor control system

    DOEpatents

    Jacox, M.G.; Drexler, R.L.; Hunt, R.N.M.; Lake, J.A.

    1994-03-29

    A nuclear reactor control system is provided in a nuclear reactor having a core operating in the fast neutron energy spectrum where criticality control is achieved by neutron leakage. The control system includes dual annular, rotatable reflector rings. There are two reflector rings: an inner reflector ring and an outer reflector ring. The reflectors are concentrically assembled, surround the reactor core, and each reflector ring includes a plurality of openings. The openings in each ring are capable of being aligned or non-aligned with each other. Independent driving means for each of the annular reflector rings is provided so that reactor criticality can be initiated and controlled by rotation of either reflector ring such that the extent of alignment of the openings in each ring controls the reflection of neutrons from the core. 4 figures.

  2. Lectures on algebraic system theory: Linear systems over rings

    NASA Technical Reports Server (NTRS)

    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.

  3. System for RFID-Enabled Information Collection

    NASA Technical Reports Server (NTRS)

    Kennedy, Timothy F. (Inventor); Fink, Patrick W. (Inventor); Lin, Gregory Y. (Inventor); Ngo, Phong H. (Inventor)

    2017-01-01

    A sensor and system provide for radio frequency identification (RFID)-enabled information collection. The sensor includes a ring-shaped element and an antenna. The ring-shaped element includes a conductive ring and an RFID integrated circuit. The antenna is spaced apart from the ring-shaped element and defines an electrically-conductive path commensurate in size and shape to at least a portion of the conductive ring. The system may include an interrogator for energizing the ring-shaped element and receiving a data transmission from the RFID integrated circuit that has been energized for further processing by a processor.

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

    NASA Astrophysics Data System (ADS)

    Cuzzi, Jeff N.

    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 of the Cassini Science Objectives.

  5. The narrow rings of Jupiter, Saturn and Uranus

    NASA Technical Reports Server (NTRS)

    Dermott, S. F.; Murray, C. D.; Sinclair, A. T.

    1980-01-01

    The origin of the newly discovered narrow ring systems around Jupiter, Saturn and Uranus is considered. It is pointed out that both the Uranian and Jovian ring systems have mean orbital radii of 1.8 planetary radii and lie within the Roche zones of their respective planets, and it is suggested that the Jovian ring is the product of the disintegration of a satellite that entered the Roche zone, and that large numbers of small particles are now in horseshoe orbits about the Lagrangian equilibrium points of the remnant chunks. Analysis of the path of a ring particle in a horseshoe orbit is shown to result in ring structures in agreement with those observed for the circular rings of Jupiter and the highly eccentric ring of Uranus. The stability of these ring systems is then considered, and it is suggested that the F ring of Saturn, which lies outside the Roche zone, represents primordial matter not yet accreted by small satellites just inside the Mimas first-order resonances.

  6. {bold {ital Ab initio}} studies of the structural and electronic properties of solid cubane

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Richardson, S.L.; Martins, J.L.

    1998-12-01

    In this paper, we report {ital ab initio} calculation of the structural and electronic properties of solid cubane (s-C{sub 8}H{sub 8}) in the local-density approximation. By using an {ital ab initio} constant pressure extended molecular dynamics method with variable cell shape proposed by Wentzcovitch, Martins, and Price, we compute a lattice parameter {ital a} and a bond angle {alpha} for the rhombohedral Bravais lattice and compare it with experimental x-ray data. We obtain bond lengths for the mononuclear C{sub 8}H{sub 8} unit of basis atoms, as well as a density of states and heat of formation. {copyright} {ital 1998} {italmore » The American Physical Society}« less

  7. A Perspective on Physics in Cuba

    NASA Astrophysics Data System (ADS)

    Handy, Carlos R.

    The author is Cuban by birth: the son of an Afro-Cuban mother and an Afro-American father. He spent the first 8 years of his life attending schools in Havana and New York City. He left Cuba in 1958 so as to gain a more uninterrupted educational experience. This led to his PhD in theoretical physics from Columbia University in 1978, followed by a post-doctoral appointment at the Los Alamos National Laboratory in New Mexico. He returned to Cuba in 1980 as a member of an academic tour organized by the University of New Mexico in Albuquerque. This provided an introduction to various government-run scientific facilities in Havana and the easternmost city of "Santiago de Cuba" in the province of Oriente.

  8. Image processing and analysis of Saturn's rings

    NASA Technical Reports Server (NTRS)

    Yagi, G. M.; Jepsen, P. L.; Garneau, G. W.; Mosher, J. A.; Doyle, L. R.; Lorre, J. J.; Avis, C. C.; Korsmo, E. P.

    1981-01-01

    Processing of Voyager image data of Saturn's rings at JPL's Image Processing Laboratory is described. A software system to navigate the flight images, facilitate feature tracking, and to project the rings has been developed. This system has been used to make measurements of ring radii and to measure the velocities of the spoke features in the B-Ring. A projected ring movie to study the development of these spoke features has been generated. Finally, processing to facilitate comparison of the photometric properties of Saturn's rings at various phase angles is described.

  9. Central circuitry in the jellyfish Aglantha. II: The ring giant and carrier systems

    PubMed

    Mackie; Meech

    1995-01-01

    1. The ring giant axon in the outer nerve ring of the jellyfish Aglantha digitale is a multinucleate syncytium 85 % of which is occupied by an electron-dense fluid-filled vacuole apparently in a Gibbs­Donnan equilibrium with the surrounding band of cytoplasmic cortex. Micropipette recordings show small (-15 to -25 mV) and large (-62 to -66 mV) resting potentials. Low values, obtained with a high proportion of the micropipette penetrations, are assumed to be from the central vacuole; high values from the cytoplasmic cortex. Background electrical activity includes rhythmic oscillations and synaptic potentials representing hair cell input caused by vibration. 2. After the ring giant axon has been cut, propagating action potentials evoked by stimulation are conducted past the cut and re-enter the axon on the far side. The system responsible (the carrier system) through-conducts at a velocity approximately 25 % of that of the ring giant axon and is probably composed of small neurones running in parallel with it. Numerous small neurones are seen by electron microscopy, some making one-way and some two-way synapses with the ring giant. 3. Despite their different conduction velocities, the two systems normally appear to fire in synchrony and at the velocity of the ring giant axon. We suggest that, once initiated, ring giant spikes propagate rapidly around the margin, firing the carrier neurones through serial synapses and giving them, in effect, the same high conduction velocity. Initiation of ring giant spikes can, however, require input from the carrier system. The spikes are frequently seen to be mounted on slow positive potentials representing summed carrier postsynaptic potentials. 4. The carrier system fires one-for-one with the giant axons of the tentacles and may mediate impulse traffic between the latter and the ring giant axon. We suggest that the carrier system may also provide the pathways from the ring giant to the motor giant axons used in escape swimming. 5. The findings show that the ring giant axon functions in close collaboration with the carrier system, increasing the latter's effective conduction velocity, and that interactions with other neuronal sub-systems are probably mediated exclusively by the carrier system.

  10. HST Observations of the Uranian Ring Plane Crossing: Early Results

    NASA Astrophysics Data System (ADS)

    Showalter, Mark R.; Lissauer, J. J.; French, R. G.; Hamilton, D. P.; Nicholson, P. D.; de Pater, I.

    2007-10-01

    Between early May and mid-August 2007, Earth was on the north side of the Uranian ring plane while the Sun was still shining on the rings’ southern face. This has provided an exceedingly rare opportunity to view the ring system via transmitted light. The ɛ ring, which typically out-shines every other component of the inner ring-moon system, has been rendered essentially invisible. We have been conducting regular imaging of the Uranian system throughout this period with the Wide Field/Planetary Camera on HST to address numerous scientific goals. (1) To search the inner Uranian system for the "shepherding” moons long believed to confine the narrow rings; (2) to study the packing density of the main rings via direct observations of their vertical thickness; (3) to search for the inner dust rings that appeared in a few Voyager images; (4) to determine the vertical thickness of the faint outer rings μ and ν (5) to obtain the most sensitive determinations of the outer rings’ colors and try to understand why ring ν is red but ring μ is blue; (6) to search for additional outer dust rings under optimal viewing geometry; and (7) to continue monitoring the seemingly chaotic orbital variations of the inner Uranian moons, particularly Mab. HST observations span mid-May to mid-September. We will present our initial results from this observing program.

  11. Planetary Rings

    NASA Astrophysics Data System (ADS)

    Esposito, Larry W.

    2011-07-01

    Preface; 1. Introduction: the allure of ringed planets; 2. Studies of planetary rings 1610-2004; 3. Diversity of planetary rings; 4. Individual ring particles and their collisions; 5. Large-scale ring evolution; 6. Moons confine and sculpt rings; 7. Explaining ring phenomena; 8. N-Body simulations; 9. Stochastic models; 10. Age and evolution of rings; 11. Saturn's mysterious F ring; 12. Neptune's partial rings; 13. Jupiter's ring-moon system after Galileo; 14. Ring photometry; 15. Dusty rings; 16. Cassini observations; 17. Summary: the big questions; Glossary; References; Index.

  12. Planetary Rings

    NASA Astrophysics Data System (ADS)

    Esposito, Larry

    2014-03-01

    Preface: a personal view of planetary rings; 1. Introduction: the allure of the ringed planets; 2. Studies of planetary rings 1610-2013; 3. Diversity of planetary rings; 4. Individual ring particles and their collisions; 5. Large-scale ring evolution; 6. Moons confine and sculpt rings; 7. Explaining ring phenomena; 8. N-body simulations; 9. Stochastic models; 10. Age and evolution of rings; 11. Saturn's mysterious F ring; 12. Uranus' rings and moons; 13. Neptune's partial rings; 14. Jupiter's ring-moon system after Galileo and New Horizons; 15. Ring photometry; 16. Dusty rings; 17. Concluding remarks; Afterword; Glossary; References; Index.

  13. Expected first-order effects of a notional equatorial ring on Earth's night sky: a geometric consideration

    NASA Astrophysics Data System (ADS)

    Hancock, L. O.

    2013-12-01

    G. Jones (1856) was first to suggest that the Earth might have its own ring, noting that an Earth ring in the ecliptic plane would account for the latitude dependence of the zodiacal light. Jones's proposal was not accepted: it is difficult to see why the ecliptic would accumulate mass within the Earth-Moon system. Very recently, however, this objection has been mitigated by the discovery of Saturn's Phoebe ring: evidently, the plane of a planetary moon's orbit has now been observed as the site of mass accumulation. An adjustment of just a few degrees from ecliptic to the plane of the lunar orbit gives Jones's proposal the boost of an existing Solar System analogue, mysterious though the analogue is. J. O'Keefe (1980) was first to suggest that an Earth ring system could drive climate: a ring in the equatorial plane, waxing and waning in optical depth, could drive the alternation of Ice Age and interglacial climates. This driver would account for the observation that the Ice Age climate was mainly a difference in winter only. Could Earth have a ring system with one or both elements? Even if light and unstable, it would be important to assess, as it could drive climate change. Dust assessments have not discovered a ring system, but they do not cover low orbits well, nor rule out very small particles stringently. Yet tiny particles can be optically important. There are many difficulties with this hypothesis: Why have ground-based observers never identified an equatorial ring, which after all should be the brightest element of a ring system? Why should a ring system be made of very small particles only? The material must be constantly falling to Earth - where is it? Finally, can we believe in the level of lunar geological activity needed to sustain an Earth ring system? This presentation addresses only one issue: Could ground-based observers have seen but misidentified an equatorial ring? To support consideration of that question, herewith a simple geometric exercise: a schema of ring effects on the southern sky: (i) extinction of extra-terrestrial light between celestial equator and horizon; (ii) brightening of extra-terrestrial light via light-through-dust effects near the southern horizon; and (iii) reflection of sunlight from celestial equator to horizon. These effects would be modulated by season (due to ring self-shadowing) and hour of the night (because of Earth's shadow). We suggest that the expected effects are not "missing" at all - similar effects are well known to observers but are taken to be fully accounted for by skyglow, airglow and light pollution, qualitatively similar phenomena that certainly exist. We conclude that ground-based observers' non-identification of an equatorial ring is not a counter-indicator of a ring's existence. As far as this consideration goes, the question of an Earth ring system is open.

  14. Planetary Rings

    NASA Technical Reports Server (NTRS)

    Cuzzi, Jeffrey N.

    1994-01-01

    Just over two decades ago, Jim Pollack made a critical contribution to our understanding of planetary ring particle properties, and resolved a major apparent paradox between radar reflection and radio emission observations. At the time, particle properties were about all there were to study about planetary rings, and the fundamental questions were, why is Saturn the only planet with rings, how big are the particles, and what are they made of? Since then, we have received an avalanche of observations of planetary ring systems, both from spacecraft and from Earth. Meanwhile, we have seen steady progress in our understanding of the myriad ways in which gravity, fluid and statistical mechanics, and electromagnetism can combine to shape the distribution of the submicron-to-several-meter size particles which comprise ring systems into the complex webs of structure that we now know them to display. Insights gained from studies of these giant dynamical analogs have carried over into improved understanding of the formation of the planets themselves from particle disks, a subject very close to Jim's heart. The now-complete reconnaissance of the gas giant planets by spacecraft has revealed that ring systems are invariably found in association with families of regular satellites, and there is ark emerging perspective that they are not only physically but causally linked. There is also mounting evidence that many features or aspects of all planetary ring systems, if not the ring systems themselves, are considerably younger than the solar system

  15. O-Ring sealing arrangements for ultra-high vacuum systems

    DOEpatents

    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.

  16. Superfluid qubit systems with ring shaped optical lattices

    PubMed Central

    Amico, Luigi; Aghamalyan, Davit; Auksztol, Filip; Crepaz, Herbert; Dumke, Rainer; Kwek, Leong Chuan

    2014-01-01

    We study an experimentally feasible qubit system employing neutral atomic currents. Our system is based on bosonic cold atoms trapped in ring-shaped optical lattice potentials. The lattice makes the system strictly one dimensional and it provides the infrastructure to realize a tunable ring-ring interaction. Our implementation combines the low decoherence rates of neutral cold atoms systems, overcoming single site addressing, with the robustness of topologically protected solid state Josephson flux qubits. Characteristic fluctuations in the magnetic fields affecting Josephson junction based flux qubits are expected to be minimized employing neutral atoms as flux carriers. By breaking the Galilean invariance we demonstrate how atomic currents through the lattice provide an implementation of a qubit. This is realized either by artificially creating a phase slip in a single ring, or by tunnel coupling of two homogeneous ring lattices. The single qubit infrastructure is experimentally investigated with tailored optical potentials. Indeed, we have experimentally realized scaled ring-lattice potentials that could host, in principle, n ~ 10 of such ring-qubits, arranged in a stack configuration, along the laser beam propagation axis. An experimentally viable scheme of the two-ring-qubit is discussed, as well. Based on our analysis, we provide protocols to initialize, address, and read-out the qubit. PMID:24599096

  17. Earth: A Ringed Planet?

    NASA Astrophysics Data System (ADS)

    Hancock, L. O.; Povenmire, H.

    2010-12-01

    Among the most beautiful findings of the Space Age have been the discoveries of planetary rings. Not only Saturn but also Jupiter, Uranus and Neptune have rings; Saturn’s ring system has structures newly discovered; even Saturn's moon Rhea itself has a ring. All these are apparently supplied by material from the planetary moons (Rhea's ring by Rhea itself). The question naturally arises, why should the Earth not have a ring, and on the other hand, if it does, why has it not been observed? No rings have yet been observed in the inner solar system, but after all, rings in the inner solar system might simply tend to be fainter and more transient than those of the outer solar system: the inner solar system is more affected by the solar wind, and the Sun’s perturbing gravitational influence is greater. J.A. O’Keefe first suggested (1980) that Earth might have a ring system of its own. An Earth ring could account for some climate events. O’Keefe remarked that formation or thickening of a ring system in Earth’s equatorial plane could drive glaciation by deepening the chill of the winter hemisphere. (It is very well established that volcanic dust is an effective agent for the extinction of sunlight; this factor can be overwhelmingly apparent in eclipse observations.) O’Keefe died in 2000 and the speculation was not pursued, but the idea of an Earth ring has a prima facie reasonableness that calls for its renewed consideration. The program of this note is to hypothesize that, as O’Keefe proposed: (a) an Earth ring system exists; (b) it affects Earth's weather and climate; (c) the tektite strewn fields comprise filaments of the ring fallen to Earth's surface on various occasions of disturbance by comets or asteroids. On this basis, and drawing on the world's weather records, together with the Twentieth Century Reanalysis by NCEP/CIRES covering the period 1870-2010 and the geology of the tektite strewn fields, we herein propose the hypothesized Earth ring system’s orbital elements and structure. Our work concludes that rings may exist in Earth’s equatorial plane and in the plane of the lunar orbit, that such rings are filamentary structures comprising segments of geologically homogeneous material flung into earth’s orbit at distinct periods of lunar volcanism, and that earth’s weather may indeed be very strongly affected by the rings. In closing, until the time of the lunar landing in 1969, the moon was considered geologically dead. But today, we have multiple lines of evidence that the Moon is still volcanically active. According to our study, this volcanism may affect weather and climate considerably. If lunar volcanism and weather on Earth are linked, then a satisfactory understanding of lunar volcanism is called for by considerations of human welfare. The subsistence farmer has an immediate need to know what is true about our Moon; food security depends on it.

  18. Evolution of Planetary Ringmoon Systems

    NASA Technical Reports Server (NTRS)

    Cuzzi, Jeffrey N.

    1995-01-01

    The last few decades have seen an avalanche of observations of planetary ring systems, both from spacecraft and from Earth. Meanwhile, we have seen steady progress in our understanding of these systems as our intuition (and our computers) catch up with the myriad ways in which gravity, fluid and statistical mechanics, and electromagnetism can combine to shape the distribution of the submicron-to-several-meter size particles which comprise ring systems. The now-complete reconnaissance of the gas giant planets by spacecraft has revealed that ring systems are invariably found in association with families of regular satellites, and there is an emerging perspective that they are not only physically but causally linked. There is also mounting evidence that many features or aspects of all planetary ring systems, if not the ring systems themselves, are considerably younger than the solar system.

  19. Seasonal variations of antioxidant imbalance in Cuban healthy men.

    PubMed

    Arnaud, J; Fleites, P; Chassagne, M; Verdura, T; Barnouin, J; Richard, M J; Chacornac, J P; Garcia, I G; Perez-Cristia, R; Favier, A E

    2001-01-01

    To determine the antioxidant imbalance in healthy Cuban men 2y after the end of the epidemic neuropathy (50 862 cases from 1991 to 1993) and to evaluate its change over 1 y. Prospective study. La Lisa health centres (Havana, Cuba). One-hundred and ninety-nine healthy middle-aged men were selected and 106 completed the study. Subjects were studied at 3 month intervals over 1 year. No invervention. An assessment of dietary intake and the determination of blood lipid peroxides (TBARS), glutathione, diglutathione, glutathione peroxidase, superoxide dismutase, vitamin E, carotenoids, copper, zinc and selenium were performed at each period. While dietary zinc, vitamins C and E, carotenoids and fat dietary intakes and blood concentrations were low for adult men compared to international reference ranges, serum TBARS concentrations were high at every period. Some significant seasonal variations were observed. The lowest carotenoids (P < 0.002) and vitamin C(P = 0.0001) intakes, serum beta-carotene (P = 0.0001) and lutein/zeaxanthin (P < 0.05) concentrations, and the highest blood TBARS (P = 0.0001) and diglutathione (P < 0.001) concentrations were observed at the end of the rainy season (October). This period seemed to pose the greatest risk of antioxidant imbalance. Cuban men still represent a vulnerable population in terms of antioxidant imbalance. A national program of vegetable growing and increase in fruit and vegetable consumption is now evaluated in Cuba.

  20. The Hispanic Americans Baseline Alcohol Survey (HABLAS): Rates and predictors of DUI across Hispanic national groups

    PubMed Central

    Caetano, Raul; Ramisetty-Mikler, Suhasini; Rodriguez, Lori A.

    2008-01-01

    This paper examines rates of self-reported driving under the influence (DUI) of alcohol and 12 month and lifetime DUI arrest rates among Mexican Americans, Puerto Ricans, Cuban Americans and South/Central Americans in the U.S. population. Using a multistage cluster sample design, a total of 5,224 individuals 18 years of age and older were selected from the household population in five metropolitan areas of the U.S.: Miami, New York, Philadelphia, Houston and Los Angeles. The survey weighted response rate was 76%. Among men, 21% of Mexican Americans, 19.9% of South/Central Americans, 11.6% of Puerto Ricans and 6.9% of Cuban Americans reported DUI. Rates were lower among women, ranging from 9.7% for Mexican Americans to 1.3% for Cuban Americans. Mexican American men had the highest 12-month arrest rate (1.6%) and the highest lifetime arrest rate (11.2%). Drinkers who reported DUI were heavier drinkers than those not reporting DUI according to a variety of indicators. However, most DUI incidents involved non-alcohol dependent drivers. Mexican Americans and South Central/Americans, men, younger drivers, those with less than high school education, those with higher income and higher alcohol consumption were more likely to report DUI and DUI arrests. These findings show that Hispanic national groups in the U.S. are diverse regarding drinking and DUI-related experiences. PMID:18329428

  1. Exploring the factor structure of the Food Cravings Questionnaire-Trait in Cuban adults

    PubMed Central

    Rodríguez-Martín, Boris C.; Molerio-Pérez, Osana

    2014-01-01

    Food cravings refer to an intense desire to eat specific foods. The Food Cravings Questionnaire-Trait (FCQ-T) is the most commonly used instrument to assess food cravings as a multidimensional construct. Its 39 items have an underlying nine-factor structure for both the original English and Spanish version; but subsequent studies yielded fewer factors. As a result, a 15-item version of the FCQ-T with one-factor structure has been proposed (FCQ-T-reduced; see this Research Topic). The current study aimed to explore the factor structure of the Spanish version for both the FCQ-T and FCQ-T-reduced in a sample of 1241 Cuban adults. Results showed a four-factor structure for the FCQ-T, which explained 55% of the variance. Factors were highly correlated. Using the items of the FCQ-T-reduced only showed a one-factor structure, which explained 52% of the variance. Both versions of the FCQ-T were positively correlated with body mass index (BMI), scores on the Food Thoughts Suppression Inventory and weight cycling. In addition, women had higher scores than men and restrained eaters had higher scores than unrestrained eaters. To summarize, results showed that (1) the FCQ-T factor structure was significantly reduced in Cuban adults and (2) the FCQ-T-reduced may represent a good alternative to efficiently assess food craving on a trait level. PMID:24672503

  2. The genus Apodrosus Marshall, 1922 in Cuba (Coleoptera, Curculionidae, Entiminae, Polydrusini)

    PubMed Central

    Anderson, Robert S.; Zhang, Guanyang

    2017-01-01

    Abstract The genus Apodrosus Marshall is newly recorded for, and revised for Cuba. Nine new species are recognized as follows: Apodrosus alberti (type locality, Granma, Parque Nacional Pico Turquino), A. alternatus (type locality, Guantánamo, El Yunque), A. franklyni (type locality, Cienfuegos, Parque Nacional Pico San Juan), A. griseus (type locality, Santiago de Cuba, Siboney-Jutici Ecological Reserve), A. mensurensis (type locality, Holguin, Parque Nacional La Mensura-Piloto), A. pseudoalternatus (type locality, Matanzas, Varahicacos), A. beckeli (type locality, Guantánamo, 8 km W. Imias), A. sandersoni (type locality, Guantánamo, Loma Lafarola), and A. zayasi (type locality, Cienfuegos, Parque Nacional Pico San Juan). A key for their identification, descriptions, summaries of natural history information and data on distributions are presented. A molecular phylogeny based on 11 species of Apodrosus from Cuba, Hispaniola and Puerto Rico is reconstructed. A sister group relationship between Polydrusus and Apodrosus is recovered with a limited sampling of the former genus. The monophyly of Apodrosus is recovered with strong support. Cuban Apodrosus are not monophyletic. Five of the six sampled Cuban species form a clade, sister to an undescribed Apodrosus species from the Dominican Republic; and, Apodrosus alternatus is sister to A. quisqueyanus Girón & Franz, 2010, a species from the Dominican Republic. Biogeographic implications for Cuban species are discussed in light of the phylogeny. PMID:28769710

  3. Histamine-binding capacities of different natural zeolites: a comparative study.

    PubMed

    Selvam, Thangaraj; Schwieger, Wilhelm; Dathe, Wilfried

    2018-06-07

    Two different natural zeolites from Cuba and Mexico, which are already being used as contemporaneous drugs or dietary supplements in Germany and Mexico, respectively, are applied in a comparative study of their histamine-binding capacities as a function of their particle sizes. The zeolites are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and N 2 -sorption measurements (BET surface areas). The Cuban zeolite contains clinoptilolite and mordenite as major phases (78% zeolite), whereas the Mexican one contains only clinoptilolite (65% zeolite). Both zeolites are apparently free from fibrous materials according to SEM. Both zeolites adsorb significant amount of histamine under the experimental conditions. Nevertheless, the results showed that the histamine-binding capacity of the Cuban zeolite is higher than the Mexican one and the smaller the particle size of zeolite, the higher the histamine-binding capacity. This difference could be due to the variation in their mineralogical compositions resulting in varied BET surface areas. Thus, the high histamine-binding capacities of Cuban zeolites seem to be due at least partly to the presence of the large-pore zeolite mordenite, providing high total pore volumes, which will be discussed in detail. For the first time, we have shown that the mineralogical compositions of natural zeolites and their particle sizes play a key role in binding histamine, which is one of the most important regulators in human physiology.

  4. The Hispanic Americans Baseline Alcohol Survey (HABLAS): Rates and predictors of DUI across Hispanic national groups.

    PubMed

    Caetano, Raul; Ramisetty-Mikler, Suhasini; Rodriguez, Lori A

    2008-03-01

    This paper examines rates of self-reported driving under the influence (DUI) of alcohol and 12-month and lifetime DUI arrest rates among Mexican Americans, Puerto Ricans, Cuban Americans and South/Central Americans in the U.S. population. Using a multistage cluster sample design, a total of 5224 individuals 18 years of age and older were selected from the household population in five metropolitan areas of the U.S.: Miami, New York, Philadelphia, Houston and Los Angeles. The survey weighted response rate was 76%. Among men, 21% of Mexican Americans, 19.9% of South/Central Americans, 11.6% of Puerto Ricans and 6.9% of Cuban Americans reported DUI. Rates were lower among women, ranging from 9.7% for Mexican Americans to 1.3% for Cuban Americans. Mexican American men had the highest 12-month arrest rate (1.6%) and the highest lifetime arrest rate (11.2%). Drinkers who reported DUI were heavier drinkers than those not reporting DUI according to a variety of indicators. However, most DUI incidents involved non-alcohol-dependent drivers. Mexican Americans and South Central/Americans, men, younger drivers, those with less than high school education, those with higher income and higher alcohol consumption were more likely to report DUI and DUI arrests. These findings show that Hispanic national groups in the U.S. are diverse regarding drinking and DUI-related experiences.

  5. Planetary Rings

    NASA Astrophysics Data System (ADS)

    Gordon, M. K.; Araki, S.; Black, G. J.; Bosh, A. S.; Brahic, A.; Brooks, S. M.; Charnoz, S.; Colwell, J. E.; Cuzzi, J. N.; Dones, L.; Durisen, R. H.; Esposito, L. W.; Ferrari, C.; Festou, M.; French, R. G.; Giuliatti-Winter, S. M.; Graps, A. L.; Hamilton, D. P.; Horanyi, M.; Karjalainen, R. M.; Krivov, A. V.; Krueger, H.; Larson, S. M.; Levison, H. F.; Lewis, M. C.; Lissauer, J. J.; Murray, C. D.; Namouni, F.; Nicholson, P. D.; Olkin, C. B.; Poulet, F.; Rappaport, N. J.; Salo, H. J.; Schmidt, J.; Showalter, M. R.; Spahn, F.; Spilker, L. J.; Srama, R.; Stewart, G. R.; Yanamandra-Fisher, P.

    2002-08-01

    The past two decades have witnessed dramatic changes in our view and understanding of planetary rings. We now know that each of the giant planets in the Solar System possesses a complex and unique ring system. Recent studies have identified complex gravitational interactions 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, or collisions between, parent bodies. Yet, as far as we have come, our understanding is far from complete. The fundamental questions confronting ring scientists at the beginning of the twenty-first century are those regarding the origin, age and evolution of the various ring systems, in the broadest context. Understanding the origin and age requires us to know the current ring properties, and to understand the dominant evolutionary processes and how they influence ring properties. Here we discuss a prioritized list of the key questions, the answers to which would provide the greatest improvement in our understanding of planetary rings. We then outline the initiatives, missions, and other supporting activities needed to address those questions, and recommend priorities for the coming decade in planetary ring science.

  6. Improved power steering with double and triple ring waveguide systems: the impact of the operating frequency.

    PubMed

    Kok, H P; de Greef, M; Borsboom, P P; Bel, A; Crezee, J

    2011-01-01

    Regional hyperthermia systems with 3D power steering have been introduced to improve tumour temperatures. The 3D 70-MHz AMC-8 system has two rings of four waveguides. The aim of this study is to evaluate whether T(90) will improve by using a higher operating frequency and whether further improvement is possible by adding a third ring. Optimised specific absorption rate (SAR) distributions were evaluated for a centrally located target in tissue-equivalent phantoms, and temperature optimisation was performed for five cervical carcinoma patients with constraints to normal tissue temperatures. The resulting T(90) and the thermal iso-effect dose (i.e. the number of equivalent min at 43°C) were evaluated and compared to the 2D 70-MHz AMC-4 system with a single ring of four waveguides. FDTD simulations were performed at 2.5 × 2.5 × 5 mm(3) resolution. The applied frequencies were 70, 100, 120, 130, 140 and 150 MHz. Optimised SAR distributions in phantoms showed an optimal SAR distribution at 140 MHz. For the patient simulations, an optimal increase in T(90) was observed at 130 MHz. For a two-ring system at 70 MHz the gain in T(90) was about 0.5°C compared to the AMC-4 system, averaged over the five patients. At 130 MHz the average gain in T(90) was ~1.5°C and ~2°C for a two and three-ring system, respectively. This implies an improvement of the thermal iso-effect dose with a factor ~12 and ~30, respectively. Simulations showed that a 130-MHz two-ring waveguide system yields significantly higher tumour temperatures compared to 70-MHz single-ring and double-ring waveguide systems. Temperatures were further improved with a 130-MHz triple-ring system.

  7. Neptune - full ring system

    NASA Technical Reports Server (NTRS)

    1989-01-01

    This pair of Voyager 2 images (FDS 11446.21 and 11448.10), two 591-s exposures obtained through the clear filter of the wide angle camera, show the full ring system with the highest sensitivity. Visible in this figure are the bright, narrow N53 and N63 rings, the diffuse N42 ring, and (faintly) the plateau outside of the N53 ring (with its slight brightening near 57,500 km).

  8. Evaluation of the feeding value of Dichrostachys cinerea pods for fattening pigs in Cuba.

    PubMed

    Martín-Casas, N; Reinoso-Pérez, M; García-Díaz, J R; Hansen, H H; Nielsen, M O

    2017-08-01

    Dichrostachys cinerea (L.) Wight & Arn. is a tropical leguminous shrub widely regarded as an invasive species in Cuba, after having invaded a significant proportion of its arable land during the past decades. Concurrently, smallholder pig producers are highly constrained by the scarcity of protein feeds. This study aimed to assess the feeding value of D. cinerea pod meal (DCPM) as an alternative protein supplement for pigs in Cuban smallholder production systems. An on-farm feeding trial was carried out with three groups (N = 10) of growing-fattening pigs over 60 days, where DCPM replaced 0, 15, and 30% in DM of a dietary commercial concentrate. Then, in an in vivo digestibility trial with eight growing pigs, apparent digestibilities of DCPM were determined for dry matter (DM), organic matter (OM) and crude protein (CP). Finally, in vitro digestibilities for OM (fecal and ileal) and CP (ileal) were determined. In the feeding trial, pig body weight gains were not affected by increased dietary substitution levels of concentrate for DCPM. Blood parameters, with a few exceptions, did not show significant differences among groups. Values for in vivo OM and CP digestibilities were 40.81 and 50.26%, and substantially higher than in vitro values. In conclusion, our results showed that at least 30% of DM in commercial concentrate could be substituted by DCPM without affecting pig growth performances under Cuban smallholder conditions. The low digestibility of DCPM is, however, not acceptable for intensive pig production systems. In vitro enzyme digestibility methods developed for commercial pig feeds are not suitable for DCPM without further calibration.

  9. Nitrogenase-mimic iron-containing chalcogels for photochemical reduction of dinitrogen to ammonia.

    PubMed

    Liu, Jian; Kelley, Matthew S; Wu, Weiqiang; Banerjee, Abhishek; Douvalis, Alexios P; Wu, Jinsong; Zhang, Yongbo; Schatz, George C; Kanatzidis, Mercouri G

    2016-05-17

    A nitrogenase-inspired biomimetic chalcogel system comprising double-cubane [Mo2Fe6S8(SPh)3] and single-cubane (Fe4S4) biomimetic clusters demonstrates photocatalytic N2 fixation and conversion to NH3 in ambient temperature and pressure conditions. Replacing the Fe4S4 clusters in this system with other inert ions such as Sb(3+), Sn(4+), Zn(2+) also gave chalcogels that were photocatalytically active. Finally, molybdenum-free chalcogels containing only Fe4S4 clusters are also capable of accomplishing the N2 fixation reaction with even higher efficiency than their Mo2Fe6S8(SPh)3-containing counterparts. Our results suggest that redox-active iron-sulfide-containing materials can activate the N2 molecule upon visible light excitation, which can be reduced all of the way to NH3 using protons and sacrificial electrons in aqueous solution. Evidently, whereas the Mo2Fe6S8(SPh)3 is capable of N2 fixation, Mo itself is not necessary to carry out this process. The initial binding of N2 with chalcogels under illumination was observed with in situ diffuse-reflectance Fourier transform infrared spectroscopy (DRIFTS). (15)N2 isotope experiments confirm that the generated NH3 derives from N2 Density functional theory (DFT) electronic structure calculations suggest that the N2 binding is thermodynamically favorable only with the highly reduced active clusters. The results reported herein contribute to ongoing efforts of mimicking nitrogenase in fixing nitrogen and point to a promising path in developing catalysts for the reduction of N2 under ambient conditions.

  10. Enriching screening libraries with bioactive fragment space.

    PubMed

    Zhang, Na; Zhao, Hongtao

    2016-08-01

    By deconvoluting 238,073 bioactive molecules in the ChEMBL library into extended Murcko ring systems, we identified a set of 2245 ring systems present in at least 10 molecules. These ring systems belong to 2221 clusters by ECFP4 fingerprints with a minimum intracluster similarity of 0.8. Their overlap with ring systems in commercial libraries was further quantified. Our findings suggest that success of a small fragment library is driven by the convergence of effective coverage of bioactive ring systems (e.g., 10% coverage by 1000 fragments vs. 40% by 2million HTS compounds), high enrichment of bioactive ring systems, and low molecular complexity enhancing the probability of a match with the protein targets. Reconciling with the previous studies, bioactive ring systems are underrepresented in screening libraries. As such, we propose a library of virtual fragments with key functionalities via fragmentation of bioactive molecules. Its utility is exemplified by a prospective application on protein kinase CK2, resulting in the discovery of a series of novel inhibitors with the most potent compound having an IC50 of 0.5μM and a ligand efficiency of 0.41kcal/mol per heavy atom. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. [Design and Analysis of CT High-speed Data Transmission Rotating Connector Ring System Retaining Ring].

    PubMed

    Pan, Li; Cao, Jujiang; Liu, Min; Fu, Weiwei

    2017-11-30

    High speed data transmission rotating connector system for signal high-speed transmission used in the fixed end and rotating end, it is one of the core component in the CT system. This paper involves structure design and analysis of the retaining ring in the CT high speed data transmission rotating connector system based on the principle of off-axis free space optical transmission. According to the problem of the actual engineering application of space limitations, optical fiber fixed and collimator installation location, we designed the structure of the retaining ring. Using the static analysis function of ANSYS Workbench, it verifies rationality and safety of the strength of retaining ring structure. And based on modal analysis function of ANSYS Workbench, it evaluates the effect of the retaining ring on the stability of the system date transmission, and provides theoretical basis for the feasibility of the structure in practical application.

  12. Planetary rings: Structure and history

    NASA Astrophysics Data System (ADS)

    Esposito, L.

    The composition and structure of planetary rings provide the key evidence to understand their origin and evolution. Before the first space observations, we were able to maintain an idealized view of the rings around Saturn, the only known ring system at that time. Rings were then discovered around Jupiter, Uranus and Neptune. Saturn's F ring was discovered by Pioneer 11. Our ideal view of circular, planar, symmetric and unchanging rings was shattered by observations of inclined, eccentric rings, waves and wavy edges, and numerous processes acting at rates that give timescales much younger than the solar system. Moons within and near the rings sculpt them and are the likely progenitors of future rings. The moonlet lifetimes are much less than Saturn's age. The old idea of ancient rings gave rise to youthful rings, that are recently created by erosion and destruction of small nearby moons. Although this explanation may work well for most rings, Saturn's massive ring system provides a problem. It is extremely improbable that Saturn's rings were recently created by the destruction of a moon as large as Mimas, or even by the breakup of a large comet that passed too close to Saturn. The history of Saturn's rings has been a difficult problem, now made even more challenging by the close-up Cassini measurements. Cassini observations show unexpected ring variability in time and space. Time variations are seen in ring edges, in the thinner D and F rings, and in the neutral oxygen cloud, which outweighs the E ring in the same region around Saturn. The rings are inhomogeneous, with structures on all scales, sharp gradients and edges. Compositional gradients are sharper than expected, but nonetheless cross structural boundaries. This is evidence for ballistic transport that has not gone to completion. The autocovariance maximizes in the middle of the A ring, with smaller structure near the main rings' outer edge. Density wave locations have a fresher ice composition. The processes of collisions, diffusion and transport should have homogenized the rings over the age of the solar system. Instead, these differences persist. The mass density in the Cassini division inferred from density waves is so low, that the material there would be ground to 1 dust in 30,000 years. The observed moons that cause such interesting structure in the rings have short lifetimes against disruption by cometary bombardment and against the angular momentum transfers that push them away from the rings. These rapid processes evident in the Cassini data have been taken as evidence that the rings were recently created, perhaps from a comet that passed too close to Saturn. Instead, an alternative is that primordial material may have been re-used and recycled. In the zone near the Roche limit where rings are found, limited accretion is possible, with the larger bodies able to recapture smaller fragments. The `propeller' structures, the self-gravity wakes, and the size distribution of clumps in Saturn's F ring are all indications of the accretion process. Recycling could extend the ring lifetime almost indefinitely. The variety evident in the latest observations and the low mass density inferred for the largest bodies are both consistent with extensive recycling of ring material as the explanation of the apparent youth of Saturn's rings. Similar processes are likely occurring tin the other ring systems and in the formation of planets around other stars. 2

  13. Results from a survey of the dynamics shaping Uranus' Mab/μ-ring system

    NASA Astrophysics Data System (ADS)

    Kumar, Kartik; de Pater, Imke; Showalter, Mark R.

    2014-11-01

    Based on Hubble Space Telescope (HST) data, Showalter and Lissauer (2006) reported the discovery of two faint rings beyond Uranus’ main rings: the ν- and μ- rings. They constitute Uranus' outer ring system and are located beyond the ɛ-ring but interior to the large classical moons. After co-adding a series of HST images, Showalter and Lissauer (2006) obtained radial profiles for both new rings. They discovered that the peak radial intensity of the μ-ring aligns closely with the orbit of Mab. Along with numerous other observations, this points to the fact that the Mab/μ-ring system is highly coupled.The discovery of the μ-ring has led to open questions about dust dynamics beyond Uranus' main rings. Like Saturn's E-ring, observations reveal that the μ-ring is blue, indicative of a pre-dominance of sub-micron-sized particles (de Pater et al., 2006). The E-ring results from plumes on Enceladus' south pole, however the origin of the μ-ring remains a mystery. The latter is likely fed by ejecta from micro-meteorite impacts with Mab, much like Jupiter's faint rings are regenerated by companion (small) moons (Burns et al., 1999). The μ-ring's steep size-distribution suggests that there is an unknown mechanism at play that hides or removes large dust particles. We present results from an investigation into the forces shaping the μ-ring. To simulate the motion of dust in the Mab/μ-ring system, we developed a numerical toolbox (Dustsim; Kumar et al., 2015) that uses Tudat (Kumar et al., 2012). We performed integrations using Dustsim that included the effects of Uranus' gravity field, titled magnetic moment, solar radiation pressure, and collisions with a putative suite of large μ-ring bodies, hypothesized as the cause of Mab's anomalous orbital motion (Kumar et al., 2014). Following on from previous studies (e.g., Sfair and Giuliatti Winter, 2009; Sfair and Giuliatti Winter, 2012), we present a survey of the expected lifetime of μ-ring dust, as a function of particle size. Our results lay the basis for further research into the hypothesis that the blueness of the μ-ring is a manifestation of size-based sorting, resulting from the natural environment.

  14. Fan blade protection system

    NASA Technical Reports Server (NTRS)

    Hermans, Thomas C. (Inventor); Wakeman, Thomas G. (Inventor); Hauser, Ambrose A. (Inventor)

    1993-01-01

    In one type of aircraft propulsion system, propeller blades are mounted on a ring which surrounds a turbine. An annular space exists between the turbine and the ring. If a propeller blade should break free, the unbalanced centrifugal load tends to deform the ring. The invention reduces the deformation, as by locating spacers between the turbine and the ring.

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Seismic structure and stratigraphy of northern edge of Bahaman-Cuban collision zone

    USGS Publications Warehouse

    Ball, M.M.; Martin, R.G.; Bock, W.D.; Sylwester, R.E.; Bowles, R.M.; Taylor, D.; Coward, E.L.; Dodd, J.E.; Gilbert, L.

    1985-01-01

    Common-depth-point (CDP) seismic reflection data in the southwestern Bahamas reveal the northern edge of the tectonized zone that resulted from the late Mesozoic-early Cenozoic collision of Cuba and the Bahamas. Two seismic facies are present. A 10-km broad anticline occurs at the south end of Santaren Channel. Platform carbonates in the core of this structure overlie Early Cretaceous and older basinal carbonate deposits and are onlapped by Late Cretaceous and Cenozoic basinal facies. The structure is inferred to be a hanging-wall anticline at the northern limit of the Cuban fold-thrust belt formed in the Late Cretaceous. A deeper water embayment extended northward into the Straits of Florida, around northern Cay Sal Bank, and back into Santaren Channel during the Early Cretaceous.

  17. Anthropometric study of Mexican primary school children.

    PubMed

    Prado-León, L R; Avila-Chaurand, R; González-Muñoz, E L

    2001-08-01

    This paper presents the results of an anthropometric survey conducted on male and female Mexican primary school children age 6-11 years in the metropolitan area of the city of Guadalajara. A set of 50 body dimensions was taken based on international standards. The sample consisted of 4758 children (boys and girls). The anthropometric measurements were compared to those of American, Cuban and Mexican children. The results indicate that the body dimensions of Mexican children from this study are different from those of American, Cuban, and other Mexican children, probably due to ethnic differences and the time lapse between the different studies. It is considered that the 50 parameters are necessary for the design of school furniture, fittings and equipment in order to minimize musculoskeletal, visual, and circulatory problems resulting from using those badly designed elements.

  18. Perceptions of adolescents, parents, and school personnel from a predominantly Cuban American community regarding dating and teen dating violence prevention.

    PubMed

    Gonzalez-Guarda, Rosa M; Cummings, Amanda M; Pino, Karen; Malhotra, Krithika; Becerra, Maria M; Lopez, Jessica E

    2014-04-01

    The purpose of this study was to explore perceptions of dating relationships and teen dating violence prevention within a predominantly Cuban American community in Miami-Dade County. Eight focus groups (n = 74 participants) with adolescents of Hispanic origin (n = 29), their parents (n = 29), and school personnel (n = 16) were conducted and analyzed using content analysis. Four themes characterized the nature and context of dating relationships among adolescents of Hispanic origin: YOLO -You Only Live Once, cultural unity but social division, dating is not going out, and the social environment challenges healthy relationships. The information generated from this study can be used to develop culturally tailored teen dating violence prevention programs targeting youth of Hispanic origin. © 2014 Wiley Periodicals, Inc.

  19. Why Did Zika Not Explode in Cuba? The Role of Active Community Participation to Sustain Control of Vector-Borne Diseases.

    PubMed

    Castro, Marta; Pérez, Dennis; Guzman, Maria G; Barrington, Clare

    2017-08-01

    As the global public health community develops strategies for sustainable Zika prevention and control, assessment of the Cuban response to Zika provides critical lessons learned. Cuba's early and successful response to Zika, grounded in the country's long-standing dengue prevention and control program, serves as a model of rapid mobilization of intersectoral efforts. Sustaining this response requires applying the evidence generated within the Cuban dengue program that active community participation improves outcomes and is sustainable and cost-effective. There is also a need for implementation science efforts to assess the transferability of lessons learned from Zika prevention and control to other pathogens and from one context to another in addition to how to take these efforts to scale.

  20. Parental attitudes toward adolescent sexuality: transcultural perspectives.

    PubMed

    DeSantis, L; Thomas, J T

    1987-08-01

    The problem of teenage pregnancy continues to impact private and public resources, affecting all socioeconomic and cultural groups. A key factor for nurse practitioners to consider when planning sex education programs is the differing parental attitudes toward teenage sexuality. These attitudes are especially important to keep in mind when dealing with parents from minority cultural groups, as these groups are often highly influential in determining the nature of adolescent sexual behavior and attitudes toward reproduction. A study of Cuban and Haitian child-rearing practices clearly demonstrates two divergent parental views of adolescent sexuality. Nurse practitioners must recognize these differing views, and individualize their approach, in order to develop culturally sensitive sex education programs for adolescents and their parents. Suggestions are provided for development of such programs for Cuban and Haitian parents and children.

  1. Planetary Ringmoon Systems

    NASA Technical Reports Server (NTRS)

    Cuzzi, J. N.; Morrison, David (Technical Monitor)

    1994-01-01

    The last decade has seen an avalanche of observations of planetary ring systems, both from spacecraft and from Earth. Much of the structure revealed was thoroughly puzzling and fired the imagination of workers in a variety of disciplines. Consequently, we have also seen steady progress in our understanding of these systems as our intuitions (and our computers) catch up with the myriad ways in which gravity, fluid and statistical mechanics, and electromagnetism can combine to shape the distribution of the submicron to-several-meter size particles which comprise ring systems (refs 1-5). The now-complete reconnaissance of the gas giant planets by spacecraft has revealed that ring systems and families of regular satellites are invariably found together, and there is an emerging perspective that they are not only physically but causally linked. There is also mounting evidence that many features or aspects of all planetary ring systems, if not the ring systems themselves, are considerably younger than the solar system.

  2. Reciprocating down-hole sand pump

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ruhle, J.L.

    1987-04-28

    This patent describes the invention of a continuously-operated reciprocating down-hole sand pump comprising: a steel polished plunger pipe that strokes back and forth within a steel honed pump barrel, and is equipped with a self-lubricating fluorocarbon V-ring system that is pressure-actuated during compression strokes; the self-lubricating fluorocarbon V-ring system also is self-actuated by means of coil springs to provide wiping action to the polished plunger pipe during suction strokes; the self-lubricating fluorocarbons V-ring system also self-adjusts by means of coil springs located adjacent the fluorocarbon V-ring so as to automatically compensate for V-ring wear; and the self-lubricating fluorocarbon V-ring systemmore » also is designed in such a manner so as to eliminate voids and discourage the extrusion of V-rings in high temperature and high-pressure applications.« less

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

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

    The mass distribution in the Saturnian ring system is investigated and compared with predictions from plasma cosmogony. According to this theory, the matter in the rings was once a magnetized plasma, in which gravitation is balanced by the centrifugal and electromagnetic forces. As the plasma is neutralized, the electromagnetic forces disappear and the matter falls in to 2/3 of the original saturnocentric distance. This causes the cosmogonic shadow effect, demonstrated for the large scale structure 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 2/3) closer to Saturn than the causing feature. Voyager data agree with an accuracy 1%.

  4. Design of illumination system in ring field capsule endoscope

    NASA Astrophysics Data System (ADS)

    Jeng, Wei-De; Mang, Ou-Yang; Chen, Yu-Ta; Wu, Ying-Yi

    2011-03-01

    This paper is researching about the illumination system in ring field capsule endoscope. It is difficult to obtain the uniform illumination on the observed object because the light intensity of LED will be changed along its angular displacement and same as luminous intensity distribution curve. So we use the optical design software which is Advanced Systems Analysis Program (ASAP) to build a photometric model for the optimal design of LED illumination system in ring field capsule endoscope. In this paper, the optimal design of illumination uniformity in the ring field capsule endoscope is from origin 0.128 up to optimum 0.603 and it would advance the image quality of ring field capsule endoscope greatly.

  5. Further explorations of cosmogonic shadow effects in the Saturnian rings

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

    The mass distribution in the Saturnian ring system is compared with predictions from the cosmogonic theory of Alfven and Arrhenius (1975) in which matter in the rings was once a magnetized plasma, with gravitation balanced by centrifugal force and 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 supports the cosmogonic shadow effect, also demonstrated for the astroidal belt and in the large scale structure of the Saturnian ring system. The relevance of the comogonic shadow effect for parts of the finer structures of the Saturnian ring system is investigated. 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 2/3) closer to Saturn than the causing feature.

  6. Jupiter's ring system - New results on structure and particle properties

    NASA Technical Reports Server (NTRS)

    Showalter, Mark R.; Burns, Joseph A.; Cuzzi, Jeffrey N.; Pollack, James B.

    1987-01-01

    Jupiter's diffuse ring system is upon reexamination of Voyager images noted to be composed of a relatively bright narrow ring and an inner toroidal halo as well as the 'gossamer' exterior ring, while the previously suspected inner disk is missing. Several narrow, bright features are visible in the main ring, and are suggested to be related in some way to Adrastea and Metis. The smallest ring particles and the dark, rough, red largest bodies both have total optical depths of 1-6 x 10 to the -6th. After arising at the bright ring's inner boundary, the halo rapidly expands inward to a 20,000-km thickness, and disappears at a radius of 90,000 km halfway between the main ring and the planet's cloudtops.

  7. Sea Surface Temperature Records Using Sr/Ca Ratios in a Siderastrea siderea Coral from SE Cuba

    NASA Astrophysics Data System (ADS)

    Fargher, H. A.; Hughen, K. A.; Ossolinski, J. E.; Bretos, F.; Siciliano, D.; Gonzalez, P.

    2015-12-01

    Sea surface temperature (SST) variability from Cuba remains relatively unknown compared to the rest of the Caribbean. Cuba sits near an inflection point in the spatial pattern of SST from the North Atlantic Oscillation (NAO), and long SST records from the region could reveal changes in the influence of this climate system through time. A Siderastrea siderea coral from the Jardínes de la Reina in southern Cuba was drilled to obtain a 220 year long archive of environmental change. The genus Siderastrea has not been extensively studied as an SST archive, yet Sr/Ca ratios in the Cuban core show a clear seasonal signal and strong correlation to instrumental SST data (r2 = 0.86 and 0.36 for monthly and interannual (winter season) timescales, respectively). Annual growth rates (linear extension) of the coral are observed to have a minor influence on Sr/Ca variability, but do not show a direct correlation to SST on timescales from annual to multidecadal. Sr/Ca measurements from the Cuban coral are used to reconstruct monthly and seasonal (winter, summer) SST extending back more than two centuries. Wintertime SST in southern Cuba is compared to other coral Sr/Ca records of winter-season SST from locations sensitive to the NAO in order to investigate the stationarity of the NAO SST 'fingerprint' through time.

  8. Validation of a portable, waterproof blood pH analyser for elasmobranchs.

    PubMed

    Talwar, Brendan; Bouyoucos, Ian A; Shipley, Oliver; Rummer, Jodie L; Mandelman, John W; Brooks, Edward J; Grubbs, R Dean

    2017-01-01

    Quantifying changes in blood chemistry in elasmobranchs can provide insights into the physiological insults caused by anthropogenic stress, and can ultimately inform conservation and management strategies. Current methods for analysing elasmobranch blood chemistry in the field are often costly and logistically challenging. We compared blood pH values measured using a portable, waterproof pH meter (Hanna Instruments HI 99161) with blood pH values measured by an i-STAT system (CG4+ cartridges), which was previously validated for teleost and elasmobranch fishes, to gauge the accuracy of the pH meter in determining whole blood pH for the Cuban dogfish ( Squalus cubensis ) and lemon shark ( Negaprion brevirostris ). There was a significant linear relationship between values derived via the pH meter and the i-STAT for both species across a wide range of pH values and temperatures (Cuban dogfish: 6.8-7.1 pH 24-30°C; lemon sharks: 7.0-7.45 pH 25-31°C). The relative error in the pH meter's measurements was ~±2.7%. Using this device with appropriate correction factors and consideration of calibration temperatures can result in both a rapid and accurate assessment of whole blood pH, at least for the two elasmobranch species examined here. Additional species should be examined in the future across a wide range of temperatures to determine whether correction factors are universal.

  9. One last look from the dark side: Cassini's final views of Saturn's rings from with the planet's shadow

    NASA Astrophysics Data System (ADS)

    Hedman, Matthew M.; Burns, Joseph A.; Nicholson, Philip D.; Tiscareno, Matthew S.; Evans, Michael W.; Baker, Emily

    2017-10-01

    Around the start of Cassini's Grand Finale, the spacecraft passed a dozen times through Saturn's shadow, enabling its cameras and spectrometers to observe the ring system at extremely high phase angles. These opportunities yielded the best combination of signal-to-noise and resolution for many parts of Saturn's fainter dusty rings, and allowed the main rings to be viewed from previously inaccessible lighting geometries. We will highlight some of the surprising features found in the data obtained by Cassini's Imaging Science Subsystem (ISS) and Visual and Infrared Mapping Spectrometer (VIMS) during these time periods, and discuss what they might be able to tell us about the structure and dynamics of Saturn's various ring systems. For example, ISS captured global views of the entire ring system that reveal previously unseen structures in dust-filled regions like the D ring and the zone between Saturn's F and G rings, as well as novel fine-scale structures in the core of the E ring near Enceladus' orbit. These structures provide new insights into the forces that sculpt these tenuous rings. ISS and VIMS also detected an unexpected brightening and highly unusual spectra of the main rings at extremely high phase angles. These data may provide novel information about the distribution of small grains and particles in these denser rings.

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

    NASA Astrophysics Data System (ADS)

    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.

  11. Integration of RAM-SCB into the Space Weather Modeling Framework

    DOE PAGES

    Welling, Daniel; Toth, Gabor; Jordanova, Vania Koleva; ...

    2018-02-07

    We present that numerical simulations of the ring current are a challenging endeavor. They require a large set of inputs, including electric and magnetic fields and plasma sheet fluxes. Because the ring current broadly affects the magnetosphere-ionosphere system, the input set is dependent on the ring current region itself. This makes obtaining a set of inputs that are self-consistent with the ring current difficult. To overcome this challenge, researchers have begun coupling ring current models to global models of the magnetosphere-ionosphere system. This paper describes the coupling between the Ring current Atmosphere interaction Model with Self-Consistent Magnetic field (RAM-SCB) tomore » the models within the Space Weather Modeling Framework. Full details on both previously introduced and new coupling mechanisms are defined. Finally, the impact of self-consistently including the ring current on the magnetosphere-ionosphere system is illustrated via a set of example simulations.« less

  12. Integration of RAM-SCB into the Space Weather Modeling Framework

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Welling, Daniel; Toth, Gabor; Jordanova, Vania Koleva

    We present that numerical simulations of the ring current are a challenging endeavor. They require a large set of inputs, including electric and magnetic fields and plasma sheet fluxes. Because the ring current broadly affects the magnetosphere-ionosphere system, the input set is dependent on the ring current region itself. This makes obtaining a set of inputs that are self-consistent with the ring current difficult. To overcome this challenge, researchers have begun coupling ring current models to global models of the magnetosphere-ionosphere system. This paper describes the coupling between the Ring current Atmosphere interaction Model with Self-Consistent Magnetic field (RAM-SCB) tomore » the models within the Space Weather Modeling Framework. Full details on both previously introduced and new coupling mechanisms are defined. Finally, the impact of self-consistently including the ring current on the magnetosphere-ionosphere system is illustrated via a set of example simulations.« less

  13. Discovery of multi-ring basins - Gestalt perception in planetary science

    NASA Technical Reports Server (NTRS)

    Hartmann, W. K.

    1981-01-01

    Early selenographers resolved individual structural components of multi-ring basin systems but missed the underlying large-scale multi-ring basin patterns. The recognition of multi-ring basins as a general class of planetary features can be divided into five steps. Gilbert (1893) took a first step in recognizing radial 'sculpture' around the Imbrium basin system. Several writers through the 1940's rediscovered the radial sculpture and extended this concept by describing concentric rings around several circular maria. Some reminiscences are given about the fourth step - discovery of the Orientale basin and other basin systems by rectified lunar photography at the University of Arizona in 1961-62. Multi-ring basins remained a lunar phenomenon until the fifth step - discovery of similar systems of features on other planets, such as Mars (1972), Mercury (1974), and possibly Callisto and Ganymede (1979). This sequence is an example of gestalt recognition whose implications for scientific research are discussed.

  14. 2-(Naphthalen-1-yl)-4-(naphthalen-1-yl­methyl­idene)-1,3-oxazol-5(4H)-one

    PubMed Central

    Gündoğdu, Cevher; Alp, Serap; Ergün, Yavuz; Tercan, Barış; Hökelek, Tuncer

    2011-01-01

    In the title compound, C24H15NO2, the oxazole ring is oriented at dihedral angles of 10.09 (4) and 6.04 (4)° with respect to the mean planes of the naphthalene ring systems, while the two naphthalene ring systems make a dihedral angle of 4.32 (3)°. Intra­molecular C—H⋯N hydrogen bonds link the oxazole N atom to the naphthalene ring systems. In the crystal, inter­molecular weak C—H⋯O hydrogen bonds link the mol­ecules into centrosymmetric dimers. π–π contacts between the oxazole and naphthalene rings and between the naphthalene ring systems [centroid–centroid distances = 3.5947 (9) and 3.7981 (9) Å] may further stabilize the crystal structure. Three weak C—H⋯π inter­actions also occur. PMID:21754548

  15. Rings Research in the Next Decade

    NASA Astrophysics Data System (ADS)

    Tiscareno, Matthew S.; Albers, N.; Brahic, A.; Brooks, S. M.; Burns, J. A.; Chavez, C.; Colwell, J. E.; Cuzzi, J. N.; de Pater, I.; Dones, L.; Durisen, R. H.; Filacchione, G.; Giuliatti Winter, S. M.; Gordon, M. K.; Graps, A.; Hamilton, D. P.; Hedman, M. M.; Horanyi, M.; Kempf, S.; Krueger, H.; Lewis, M. C.; Lissauer, J. J.; Murray, C. D.; Nicholson, P. D.; Olkin, C. B.; Pappalardo, R. T.; Salo, H.; Schmidt, J.; Showalter, M. R.; Spahn, F.; Spilker, L. J.; Srama, R.; Sremcevic, M.; Stewart, G. R.; Yanamandra-Fisher, P.

    2009-12-01

    The study of planetary ring systems is 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-based observations.

  16. Annular ring zoom system using two positive axicons

    NASA Astrophysics Data System (ADS)

    Dickey, Fred M.; Conner, Jacob D.

    2011-10-01

    The production of an annular ring of light with a variable diameter has applications in laser material processing and machining, particle manipulation, and corneal surgery. This can readily be accomplished using a positive and negative axicon pair. However, negative axicons are very expensive and difficult to obtain with small diameters. In this paper, we present a design of an annular ring zoom system using two positive axicons. One axicon is placed a distance before a primary lens that is greater than some prescribed minimum, and the second axicon is placed after the primary lens. The position of the second axicon determines the ring diameter. The ring diameter can be zoomed from some maximum design size to a zero diameter ring (spot). Experimental results from a developmental system will be presented.

  17. The Search for Ringed Exoplanets

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2017-04-01

    Are planetary rings as common in our galaxy as they are in our solar system? A new study demonstrates how we might search for ringed exoplanets and then possibly finds one!Saturns Elsewhere?Artists illustration of the super ring system around exoplanet J1407b. This is the only exoplanet weve found with rings, but its not at all like Saturn. [Ron Miller]Our solar system is filled with moons and planetary rings, so it stands to reason that exoplanetary systems should exhibit the same features. But though weve been in the planet-hunting game for decades, weve only found one exoplanet thats surrounded by a ring system. Whats more, that system J1407b has enormous rings that are vastly different from the modest, Saturn-like rings that we might expect to be more commonplace.Have we not discovered ringed exoplanets just because theyre hard to identify? Or is it because theyre not out there? A team of scientists led by Masataka Aizawa (University of Tokyo) has set out to answer this question by conducting a systematic search for rings around long-period planet candidates.The transit light curve of KIC 10403228, shown with three models: the best-fitting planet-only model (blue) and the two best-fitting planet+ring models (green and red). [Aizawa et al. 2017]The Hunt BeginsWhy long-period planets? Rings are expected to be unstable as the planet gets closer to the central star. Whats more, the planet needs to be far enough away from the stars warmth for the icy rings to exist. The authors therefore select from the collection of candidate transiting planets 89 long-period candidates that might be able to host rings.Aizawa and collaborators then fit single-planet models (with no rings) to the light curves of these planets and search for anomalies curves that arent fit well by these standard models. Particularly suspicious characteristics include a long ingress/egress as the planet moves across the face of the star, and asymmetry of the transit shape.After applying a series of checks to eliminate false positives, the authors are left with one candidate: KIC 10403228.Rings or Not?Schematics of the two best-fitting ringed-exoplanet models for KIC 10403228, and the possible parameters of the system. The planet crosses the disk of the star from left to right with a grazing transit. [Adapted from Aizawa et al. 2017]Next, the authors apply a wide range of ringed-exoplanet models to KIC 10403228s light curve. They find two different scenarios that fit the data well: one in which the ring is significantly tilted with respect to the orbital plane, and another in which its only slightly tilted.The authors conclude by testing a variety of other scenarios that could explain the anomalies in the light curve instead. They find that two other scenarios are plausible: 1) the star is in an eclipsing binary system, with the second star surrounded by a circumstellar disk, and 2) the star is part of a hierarchical triple, and the transits are caused by a binary star system as it orbits KIC 10403228.Though Aizawa and collaborators arent able to rule either of these other two scenarios out, they suggest that follow-up spectroscopy or high-resolution imaging may help distinguish between the different scenarios. In the meantime, their methodology for systematically searching for ringed exoplanets has proven worthwhile, and they plan to extend it now to a larger data set. Perhaps well soon find other Saturn-like planets in our galaxy!CitationMasataka Aizawa () et al 2017 AJ 153 193. doi:10.3847/1538-3881/aa6336

  18. Improved piston ring materials for 650 deg C service

    NASA Technical Reports Server (NTRS)

    Bjorndahl, W. D.

    1986-01-01

    A program to develop piston ring material systems which will operate at 650C was performed. In this program, two candidate high temperature piston ring substrate materials, Carpenter 709-2 and 440B, were hot formed into the piston ring shape and subsequently evaluated. In a parallel development effort ceramic and metallic piston ring coating materials were applied to cast iron rings by various processing techniques and then subjected to thermal shock and wear evaluation. Finally, promising candidate coatings were applied to the most thermally stable hot formed substrate. The results of evaluation tests of the hot formed substrate show that Carpenter 709-2 has greater thermal stability than 440B. Of the candidate coatings, plasma transferred arc (PTA) applied tungsten carbide and molybdenum based systems exhibit the greatest resistance to thermal shock. For the ceramic based systems, thermal shock resistance was improved by bond coat grading. Wear testing was conducted to 650C (1202F). For ceramic systems, the alumina/titania/zirconia/yttria composition showed highest wear resistance. For the PTA applied systems, the tungsten carbide based system showed highest wear resistance.

  19. Automatic flatness detection system for micro part

    NASA Astrophysics Data System (ADS)

    Luo, Yi; Wang, Xiaodong; Shan, Zhendong; Li, Kehong

    2016-01-01

    An automatic flatness detection system for micro rings is developed. It is made up of machine vision module, ring supporting module and control system. An industry CCD camera with the resolution of 1628×1236 pixel, a telecentric with magnification of two, and light sources are used to collect the vision information. A rotary stage with a polished silicon wafer is used to support the ring. The silicon wafer provides a mirror image and doubles the gap caused by unevenness of the ring. The control system comprise an industry computer and software written in LabVIEW Get Kernel and Convolute Function are selected to reduce noise and distortion, Laplacian Operator is used to sharp the image, and IMAQ Threshold function is used to separate the target object from the background. Based on this software, system repeating precision is 2.19 μm, less than one pixel. The designed detection system can easily identify the ring warpage larger than 5 μm, and if the warpage is less than 25 μm, it can be used in ring assembly and satisfied the final positionary and perpendicularity error requirement of the component.

  20. Origin of invasive Florida frogs traced to Cuba

    PubMed Central

    Heinicke, Matthew P.; Diaz, Luis M.; Hedges, S. Blair

    2011-01-01

    Two of the earliest examples of successful invasive amphibians are the greenhouse frog (Eleutherodactylus planirostris) and the Cuban treefrog (Osteopilus septentrionalis) in Florida. Although both are generally assumed to be recent introductions, they are widespread on Caribbean islands and also have been proposed as natural colonizers. We obtained nucleotide sequence data for both species and their closest relatives in their native and introduced ranges. Phylogenetic analyses trace the origin of E. planirostris to a small area in western Cuba, while O. septentrionalis is derived from at least two Cuban sources, one probably a remote peninsula in western Cuba. The tropical-to-temperate invasion began with colonization of the Florida Keys followed by human-mediated dispersal within peninsular Florida. The subtropical Keys may have served as an adaptive stepping stone for the successful invasion of the North American continent. PMID:21270024

  1. A Comprehensive Study of the Development of Physics in Cuba from 1959

    NASA Astrophysics Data System (ADS)

    Baracca, Angelo; Fajer Avila, Víctor Luis; Rodríguez Castellanos, Carlos

    The present paper aims to reconstruct the main stages of the above-mentioned process from the Cuban Revolution (1959) to the present time. A general premise is necessary on the documentary sources used and the method adopted in this research. The written documents available on the development of physics in Cuba related to the early two decades are quite scarce, so that the reconstruction presented here is based mainly on oral history research. Most of the information presented in this study is sourced from interviews with Cuban colleagues who played leading roles in the events described here. This approach obviously implies drawbacks since the information obtained relies on the personal memories and views of the interviewees, and in some cases uncertain or controversial aspects arise. Despite this drawback, every effort has been made to verify the information.

  2. Water Oxidation Catalysis by Co(II) Impurities in Co(III) 4O 4 Cubanes

    DOE PAGES

    Ullman, Andrew M.; Liu, Yi; Huynh, Michael; ...

    2014-11-18

    Here, the observed water oxidation activity of the compound class Co 4O 4(OAc) 4(Py–X) 4 emanates from a Co(II) impurity. This impurity is oxidized to produce the well-known Co-OEC heterogeneous cobaltate catalyst, which is an active water oxidation catalyst. We present results from electron paramagnetic resonance spectroscopy, nuclear magnetic resonance line broadening analysis, and electrochemical titrations to establish the existence of the Co(II) impurity as the major source of water oxidation activity that has been reported for Co 4O 4 molecular cubanes. Differential electrochemical mass spectrometry is used to characterize the fate of glassy carbon at water oxidizing potentials andmore » demonstrate that such electrode materials should be used with caution for the study of water oxidation catalysis.« less

  3. Ciguatera fish poisoning in la Habana, Cuba: a study of local social-ecological resilience.

    PubMed

    Morrison, Karen; Aguiar Prieto, Pablo; Castro Domínguez, Arnaldo; Waltner-Toews, David; Fitzgibbon, John

    2008-09-01

    Following the collapse of the Cuban economy in the early 1990s, epidemiologists in the Cuban Ministry of Health noticed dramatic increases in reported outbreaks of ciguatera fish poisoning (CFP) in some coastal communities. This article summarizes the results of a comparative case study which applied an ecosystem approach to human health to investigate this issue. Situated learning and complexity theories were used to interpret the results of the investigation. CFP outbreaks are influenced by a complex set of interactions between ecological and socioeconomic processes. This study found that the level of organization of the local sports fishing community and the degree of degradation of the local nearshore marine ecosystem appear to be key factors influencing the diverging levels of CFP outbreaks recorded in the 1990s in the communities studied.

  4. Can Universities Develop Advanced Technology and Solve Social Problems?

    NASA Astrophysics Data System (ADS)

    Pérez Ones, Isarelis; Núñez Jover, Jorge

    This paper presents case studies on how Cuban universities have increasingly become directly involved with the economic and social development of the country. The paper shows how Cuban universities, from the early 1980s and early 1990s, started reorientation and organization of their scientific research, becoming more directly and intensely involved in the economic and social development of the country. In this way, special reference is made to the case of a research group at the University of Havana: the Laboratory of Synthetic Antigens. This group developed the first synthetic vaccine for human use approved in the world. In the article, public policies involved in this success as well as different obstacles are discussed. These obstacles demonstrate the difficulties and challenges that universities face when carrying out research and innovation activities related to economic and social development.

  5. The malaria parasite Plasmodium relictum in the endemic avifauna of eastern Cuba.

    PubMed

    Soares, Letícia; Marra, Peter; Gray, Lindsey; Ricklefs, Robert E

    2017-12-01

    Island populations are vulnerable to introduced pathogens, as evidenced by extinction or population decline of several endemic Hawaiian birds caused by the malaria parasite, Plasmodium relictum (order Haemosporida). We analyzed blood samples from 363 birds caught near Guantánamo Bay, Cuba, for the presence of haemosporidian infections. We characterized parasite lineages by determining nucleotide variation of the parasite's mitochondrial cyt b gene. Fifty-nine individuals were infected, and we identified 7 lineages of haemosporidian parasites. Fifty individuals were infected by 6 Haemoproteus sp. lineages, including a newly characterized lineage of Haem. (Parahaemoproteus) sp. CUH01. Nine individuals carried the P. relictum lineage GRW4, including 5 endemic Cuban Grassquits (Tiaris canorus) and 1 migratory Cape May Warbler (Setophaga tigrina). A sequence of the merozoite surface protein gene from one Cuban Grassquit infected with GRW4 matched that of the Hawaiian haplotype Pr9. Our results indicate that resident and migratory Cuban birds are infected with a malaria lineage that has severely affected populations of several endemic Hawaiian birds. We suggest GRW4 may be associated with the lack of several bird species on Cuba that are ubiquitous elsewhere in the West Indies. From the standpoint of avian conservation in the Caribbean Basin, it will be important to determine the distribution of haemosporidian parasites, especially P. relictum GRW4, in Cuba as well as the pathogenicity of this lineage in species that occur and are absent from Cuba. © 2017 Society for Conservation Biology.

  6. 2,4 Diamino benzonitrile

    NASA Technical Reports Server (NTRS)

    Frost, Lawrence W. (Inventor)

    1980-01-01

    Deep curable polymers having heterocyclic ring systems such as isoindoloquinazolinedione ring systems prepared from novel cyanoimide polymers, most desirably 2'-cyanoimide polymers. Preferably the cyanoimide polymers are prepared from a diamine having at least one nitrile group in the two position to an amine group and a dianhydride having at least two cyclic anhydride groups. Copolymers may be prepared having other linkages, notably imide linkages, in addition to isoindoloquinazolinedione ring systems and/or other similar heterocyclic ring systems. The copolymers can be prepared by use of diamines containing one or more cyanoimide groupings and/or imide groups in their structure.

  7. Methyl 6-eth-oxy-3-phenyl-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a-car-boxylate.

    PubMed

    Suresh, G; Srinivasan, J; Bakthadoss, M; Aravindhan, S

    2013-02-01

    In the title compound, C(20)H(19)NO(5), the dihedral angle between the mean plane of the pyran ring (which has a half-chair conformation) and the benzene ring of the chromeno ring system is 7.21 (7)°. The dihedral angle between the mean plane of the chromeno ring system and the isoxazole ring is 21.78 (6)°, while the isoxazole ring forms a dihedral angle of 72.60 (8)° with the attached phenyl ring. In the crystal, mol-ecules are linked via pairs of C-H⋯O hydrogen bonds, forming inversion dimers with an R(2) (2)(10) ring motif. These dimers are linked via C-H⋯N hydrogen bonds, forming chains along [001].

  8. Coherence resonance and stochastic resonance in directionally coupled rings

    NASA Astrophysics Data System (ADS)

    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.

  9. Nitrogenase-mimic iron-containing chalcogels for photochemical reduction of dinitrogen to ammonia

    DOE PAGES

    Liu, Jian; Kelley, Matthew S.; Wu, Weiqiang; ...

    2016-05-02

    A nitrogenase-inspired biomimetic chalcogel system comprising double-cubane [Mo 2Fe 6S 8(SPh) 3] and single-cubane (Fe 4S 4) biomimetic clusters demonstrates photocatalytic N 2 fixation and conversion to NH 3 in ambient temperature and pressure conditions. Replacing the Fe 4S 4 clusters in this system with other inert ions such as Sb 3+, Sn 4+, Zn 2+ also gave chalcogels that were photocatalytically active. Finally, molybdenum-free chalcogels containing only Fe 4S 4 clusters are also capable of accomplishing the N2 fixation reaction with even higher efficiency than their Mo 2Fe 6S 8(SPh) 3-containing counterparts. In this study, our results suggest thatmore » redox-active iron-sulfide–containing materials can activate the N 2 molecule upon visible light excitation, which can be reduced all of the way to NH 3 using protons and sacrificial electrons in aqueous solution. Evidently, whereas the Mo 2Fe 6S 8(SPh) 3 is capable of N 2 fixation, Mo itself is not necessary to carry out this process. The initial binding of N 2 with chalcogels under illumination was observed with in situ diffuse-reflectance Fourier transform infrared spectroscopy (DRIFTS). 15N 2 isotope experiments confirm that the generated NH 3 derives from N 2. Density functional theory (DFT) electronic structure calculations suggest that the N 2 binding is thermodynamically favorable only with the highly reduced active clusters. Finally, the results reported herein contribute to ongoing efforts of mimicking nitrogenase in fixing nitrogen and point to a promising path in developing catalysts for the reduction of N 2 under ambient conditions.« less

  10. An approach to develop an algorithm to detect the climbing height in radial-axial ring rolling

    NASA Astrophysics Data System (ADS)

    Husmann, Simon; Hohmann, Magnus; Kuhlenkötter, Bernd

    2017-10-01

    Radial-axial ring rolling is the mainly used forming process to produce seamless rings, which are applied in miscellaneous industries like the energy sector, the aerospace technology or in the automotive industry. Due to the simultaneously forming in two opposite rolling gaps and the fact that ring rolling is a mass forming process, different errors could occur during the rolling process. Ring climbing is one of the most occurring process errors leading to a distortion of the ring's cross section and a deformation of the rings geometry. The conventional sensors of a radial-axial rolling machine could not detect this error. Therefore, it is a common strategy to roll a slightly bigger ring, so that random occurring process errors could be reduce afterwards by removing the additional material. The LPS installed an image processing system to the radial rolling gap of their ring rolling machine to enable the recognition and measurement of climbing rings and by this, to reduce the additional material. This paper presents the algorithm which enables the image processing system to detect the error of a climbing ring and ensures comparable reliable results for the measurement of the climbing height of the rings.

  11. Applied Science in Cuba.

    ERIC Educational Resources Information Center

    Fox, Jeffrey L.

    1986-01-01

    Discusses various topics and issues related to the scientific enterprise in Cuba. Notes that Cuban science is emphasizing biotechnology and research on the island's chief crop (sugarcane), although hampered by limited personnel and lack of modern laboratory equipment. (JN)

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

    PubMed

    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.

  13. A Herschel-Resolved Debris Disk Around the Nearby G Star HIP 32480

    NASA Technical Reports Server (NTRS)

    Stapelfeldt, K.

    2011-01-01

    The Herschel Space Observatory is providing unprecedented sensitivity and angular resolution in the far-infrared. The DUNES Key Project (DUst around NEarby Stars, PI Carlos Eiroa) has finished its survey of 133 FGK stars within 25 pc of the Sun using the PACS photometer at 100 and 160 microns. We report the detection of a resolved debris ring around HIP 32480, a G0 star 16.5 parsecs distant. The ring is almost 300 AU in diameter and inclined 30 degrees from edge-on. We present a thermal emission model for the system that fits the Spitzer spectroscopy and Herschel images of the system. We find a minimum grainsize of approximately 4 microns in the main ring and a distinct warm dust population interior to it. Faint detached emission features just outside the ring may trace a separate, more distant ring in the system. The non-detection of the ring in archival HST/ACS coronagraphic images limits the dust grain albedo in the ring to be no more than 10%.

  14. A Resolved Debris Disk Around the Nearby G Star HIP 32480

    NASA Technical Reports Server (NTRS)

    Stapelfeldt, K. R.; Bryden, G. C.; Marshall, J.; Eiroa, C.; Absil, O.; Mora, A.; Krist, J. E.; Su, K. Y. L.

    2012-01-01

    The Herschel Space Observatory is providing unprecedented sensitivity and angular resolution in the far-infrared. The DUNES Key Project (DUst around NEarby Stars, PI Carlos Eiroa) has finished its survey of 133 FGK stars within 25 pc of the Sun using the PACS photometer at 100 and 160 microns. We report the detection of a resolved debris ring around HIP 32480, a GO star 16.5 parsecs distant. The ring is almost 300 AU in diameter and inclined 30 degrees from edge-on. We present a thermal emission model for the system that fits the Spitzer spectroscopy and Herschel images of the system. We find a minimum grain-size of 4 microns in the main ring and a distinct warm dust population interior to it. Faint detached emission features just outside the ring may trace a separate, more distant ring in the system. The non-detection of the ring in archival HST/ACS coronagraphic images limits the dust grain albedo in the ring to be no more than 10%.

  15. Uranus Ring System

    NASA Image and Video Library

    1996-01-29

    This image captured by NASA's Voyager 2 in 1986 revealed a continuous distribution of small particles throughout the Uranus ring system. This unique geometry, the highest phase angle at which Voyager imaged the rings, allowed us to see lanes of fine dust. http://photojournal.jpl.nasa.gov/catalog/PIA00142

  16. Mechanical evaluation of aluminum alloy ring fixator.

    PubMed

    Tosborvorn, Somboon; Cheechareon, Sukrom; Ruttanuchun, Kittiput; Sirivedin, Suparerk; Rhienumporn, Chaitawat

    2006-11-01

    To test the homemade ring fixator as a tool for correction of bony deformity. The authors developed an aluminum alloy ring fixator and tested it to find out the accuracy of manufacturing and strength of the ring systems under axial load with the Roundness Testing Machine and Lloyd Universal Testing Machine. The mean diameter of the twenty five-drill holes was 6.5843872 +/- 0.0521594 mm (mean +/- SD). Distance between particular drill holes, which reflected the precision of drilling, had a high accuracy with standard deviation from 0.1138 to 0.1870 mm. The roundness of the rings was 0.2421376 +/- 0.12437977 mm (mean +/- SD). The system structure had minimal permanent deformity at breaking point, mean yield strength of the system was 4786.9 +/- 14.353 N (mean +/- SD). This was caused by the failure of the wire. Mean stiffness of the system was 127 N./mm. The aluminum alloy ring fixator was strong enough and well tolerated for clinical usage

  17. ARC-1989-A89-7042

    NASA Image and Video Library

    1989-08-11

    P-34578 BW One of two new ring arcs, or partial rings, discovered by Voyager 2, is faintly visible just outside the orbit of the Neptunian moon 1989N4.The 155-second exposure taken by the spacecraft's narrow-angle camera shows the glare of an overexposed Neptune to the right of the moon and ring arc. The two bright streaks below the moon and ring arc are stars. The ring arc is approximately 50,000 kilometers (30,000 miles) long. The second ring arc, not apparent here, is about 10,000 kilometers (6,000 miles) long and is assoiciated with moon 1989N3. The ring arc, along with 1989N4, orbits about 62,000 kilometers (38,000 miles) from the planet's cloud tops. Astronomers long suspected the existence of such an irregular ring system around Neptune. Data from repeated ground-based observations hinted at the existence of irregular strands of partial rings orbiting Neptune. Voyager's photographs of the ring arcs are the first photographic evidence that such a ring system exists. Voyager scientists said the ring arcs may be comprised of debris associated with the nearby moons, or may be the remnants of moons that have been torn apart or ground down through collisions. Close-up studies of the ring arcs by Voyager 2 will help determine their composition.

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

    PubMed Central

    Liu, Cheng; Zhang, Yong-Fang; Li, Sha; Müller, Norbert

    2017-01-01

    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. PMID:28732042

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

    PubMed

    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.

  20. Two-mode division multiplexing in a silicon-on-insulator ring resonator.

    PubMed

    Dorin, Bryce A; Ye, Winnie N

    2014-02-24

    Mode-division multiplexing (MDM) is an emerging multiple-input multiple-output method, utilizing multimode waveguides to increase channel numbers. In the past, silicon-on-insulator (SOI) devices have been primarily focused on single-mode waveguides. We present the design and fabrication of a two-mode SOI ring resonator for MDM systems. By optimizing the device parameters, we have ensured that each mode is treated equally within the ring. Using adiabatic Bezier curves in the ring bends, our ring demonstrated a signal-to-crosstalk ratio above 18 dB for both modes at the through and drop ports. We conclude that the ring resonator has the potential for filtering and switching for MDM systems on SOI.

  1. Excitonic energy transfer in light-harvesting complexes in purple bacteria

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ye Jun; Sun Kewei; Zhao Yang

    Two distinct approaches, the Frenkel-Dirac time-dependent variation and the Haken-Strobl model, are adopted to study energy transfer dynamics in single-ring and double-ring light-harvesting (LH) systems in purple bacteria. It is found that the inclusion of long-range dipolar interactions in the two methods results in significant increase in intra- or inter-ring exciton transfer efficiency. The dependence of exciton transfer efficiency on trapping positions on single rings of LH2 (B850) and LH1 is similar to that in toy models with nearest-neighbor coupling only. However, owing to the symmetry breaking caused by the dimerization of BChls and dipolar couplings, such dependence has beenmore » largely suppressed. In the studies of coupled-ring systems, both methods reveal an interesting role of dipolar interactions in increasing energy transfer efficiency by introducing multiple intra/inter-ring transfer paths. Importantly, the time scale (4 ps) of inter-ring exciton transfer obtained from polaron dynamics is in good agreement with previous studies. In a double-ring LH2 system, non-nearest neighbor interactions can induce symmetry breaking, which leads to global and local minima of the average trapping time in the presence of a non-zero dephasing rate, suggesting that environment dephasing helps preserve quantum coherent energy transfer when the perfect circular symmetry in the hypothetic system is broken. This study reveals that dipolar coupling between chromophores may play an important role in the high energy transfer efficiency in the LH systems of purple bacteria and many other natural photosynthetic systems.« less

  2. Large transient fault current test of an electrical roll ring

    NASA Technical Reports Server (NTRS)

    Yenni, Edward J.; Birchenough, Arthur G.

    1992-01-01

    The space station uses precision rotary gimbals to provide for sun tracking of its photoelectric arrays. Electrical power, command signals and data are transferred across the gimbals by roll rings. Roll rings have been shown to be capable of highly efficient electrical transmission and long life, through tests conducted at the NASA Lewis Research Center and Honeywell's Satellite and Space Systems Division in Phoenix, AZ. Large potential fault currents inherent to the power system's DC distribution architecture, have brought about the need to evaluate the effects of large transient fault currents on roll rings. A test recently conducted at Lewis subjected a roll ring to a simulated worst case space station electrical fault. The system model used to obtain the fault profile is described, along with details of the reduced order circuit that was used to simulate the fault. Test results comparing roll ring performance before and after the fault are also presented.

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

    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.

  5. The discipline of ergonomics in Cuba within the occupational health framework: background and trends.

    PubMed

    Torres, Yaniel; Rodríguez, Yordán; Viña, Silvio

    2013-01-01

    The concept of ergonomics was introduced in Cuba at the beginning of the 1970s. More than 40 years later, the prevailing approach to workers' health is still generally reactive rather than proactive, despite the commitment of the government to the subject. A factor influencing this issue is, generally, lack of recognition of the benefits of establishing ergonomic principles within most occupational activities. Recent progress to move occupational health practice toward a more preventive approach has been conducted, frequently with international support. The introduction of a set of Cuban standards proposing the necessity of ergonomic evaluations is an example of this progress. The main challenge for Cuban ergonomists is to transfer knowledge to occupational health practitioners in order to be in concordance with basic standards and regulations regarding ergonomics. The article offers a short description of the history of ergonomics and an overview of ergonomics practice in Cuba.

  6. Anthropology and style of life in middle age women.

    PubMed

    Prado Martinez, Consuelo; Diaz, María Elena; Toledo, Emilia María; Carmenate, María Margarita; Wong, Iraida; Moreno, Raisa; Moreno, Vilma

    2003-06-01

    The anthropometric pattern, demographics data, lifestyle factors and several aspects of morbidity were analyzed for 400 Cuban women ages 40-60 years. More than 85% of women were obese, being these in direct association with morphology typically androgens, more evident in the postmenopausal women. In these women observed less body mass index and overweight, in an equivalent way between pre and postmenopausal women. A moderate consumption of rice, was evidenced, pastas and vegetables, few candies and fatty, what points to or quite acceptable knowledge of the harmful effect of some foods, to weigh that the shadowy use of saturated fats and not saturated it was the most frequent thing. By multifactor approach it is possible to make relation between nutritional patterns, morphology and climacteric symptoms; Cuban women present a different frequencies from an other literature showing the risk of generalist this studies and health's actions.

  7. Hispanics: at risk for adolescent pregnancy?

    PubMed

    Pletsch, P K

    1990-06-01

    Data from the Hispanic Health and Nutrition Examination Survey, 1982-1984, were analyzed to describe pregnancy, miscarriage, and age-specific birth rates as well as oral contraceptive use among Mexican-American, Puerto Rican, and Cuban-American females age 12 to 19 years. The Cuban-American sample (n = 85) had the lowest pregnancy (99) and fertility (37) rates, with 6.5% ever having used oral contraceptives. In the Mexican-American (n = 638) and Puerto Rican women (n = 300) the pregnancy and fertility rates were 205 and 223, and 141 and 110, respectively. Of these two groups, 14.5% and 12.6% had ever used oral contraceptives. These results suggest that Mexican-Americans and Puerto Ricans are at risk for adolescent pregnancy, with the latter having more of the sociodemographic characteristics associated with the long-term disadvantages of early childbearing. These facts have implications for nursing practice and research.

  8. Level crossings and zero-field splitting in the {Cr8}-cubane spin cluster studied using inelastic neutron scattering and magnetization

    NASA Astrophysics Data System (ADS)

    Vaknin, D.; Garlea, V. O.; Demmel, F.; Mamontov, E.; Nojiri, H.; Martin, C.; Chiorescu, I.; Qiu, Y.; Kögerler, P.; Fielden, J.; Engelhardt, L.; Rainey, C.; Luban, M.

    2010-11-01

    Inelastic neutron scattering (INS) in variable magnetic field and high-field magnetization measurements in the millikelvin temperature range were performed to gain insight into the low-energy magnetic excitation spectrum and the field-induced level crossings in the molecular spin cluster {Cr8}-cubane. These complementary techniques provide consistent estimates of the lowest level-crossing field. The overall features of the experimental data are explained using an isotropic Heisenberg model, based on three distinct exchange interactions linking the eight CrIII paramagnetic centers (spins s = 3/2), that is supplemented with a relatively large molecular magnetic anisotropy term for the lowest S = 1 multiplet. It is noted that the existence of the anisotropy is clearly evident from the magnetic field dependence of the excitations in the INS measurements, while the magnetization measurements are not sensitive to its effects.

  9. Level crossings and zero-field splitting in the {Cr8}-cubane spin-cluster studied using inelastic neutron scattering and magnetization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vaknin, D.; Garlea, Vasile O; Demmel, F.

    Inelastic neutron scattering (INS) in variable magnetic field and high-field magnetization measurements in the millikelvin temperature range were performed to gain insight into the low-energy magnetic excitation spectrum and the field-induced level crossings in the molecular spin cluster {Cr8}-cubane. These complementary techniques provide consistent estimates of the lowest level-crossing field. The overall features of the experimental data are explained using an isotropic Heisenberg model, based on three distinct exchange interactions linking the eight CrIII paramagnetic centers (spins s = 3/2), that is supplemented with a relatively large molecular magnetic anisotropy term for the lowest S = 1 multiplet. It ismore » noted that the existence of the anisotropy is clearly evident from the magnetic field dependence of the excitations in the INS measurements, while the magnetization measurements are not sensitive to its effects.« less

  10. On some Cuban species of the genus Longior Travassos & Kloss, 1958 (Oxyurida, Hystrignathidae), with description of a new species

    PubMed Central

    Morffe, Jans; García, Nayla

    2011-01-01

    Abstract Longior zayasi Coy, García & Alvarez, 1993 is established as incertae sedis because the males (declared as the holotype) are inconsistent with the generic diagnosis, particularly in relation to the morphology of the head and tail. Thus, the females of Longior zayasi species (which agree with the generic diagnosis) are renamed and re-described as Longior longior Morffe & García sp. n. We also described males found in the sample and considered as conspecific with the new species. A comparative table with the measurements of the most of the records of Longior longior is given. The male of Longior similis Morffe, García & Ventosa, 2009 is described from the type locality of the species and compared with the known males of the genus. A key to the females of the Cuban Longior is given. PMID:21594153

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

    NASA Astrophysics Data System (ADS)

    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.

  12. No evidence of rings around Neptune

    NASA Technical Reports Server (NTRS)

    Elliot, J. L.; Mink, D. J.; Baron, R. L.; Dunham, E.; Pingree, J. E.; French, R. G.; Elias, J. H.; Liller, W.; Nicholson, P. D.; Jones, T. J.

    1981-01-01

    The results of two observations of stellar occultations of Neptune to determine if the planet has a ring system are reported. The sightings were made from Mt. Stromlo, Mauna Kea, and Cerro Tololo, noting that an equatorial ring would subtend only two arcsec of view. An upper accretion limit was defined to set the region around Neptune where rings, rather than satellites, could form. The intensities of the starlight from the two selected stars were recorded by photometers on magnetic tape during the occultation period. One of the stars did not occult, but passed through the entire region where a ring system might be present. No definitive evidence for rings was found, although an optical depth for a Neptunian ring was calculated at 0.07, with a width of more than 5 km and a radius of 31,400 km.

  13. Saturn's largest ring.

    PubMed

    Verbiscer, Anne J; Skrutskie, Michael F; Hamilton, Douglas P

    2009-10-22

    Most planetary rings in the Solar System lie within a few radii of their host body, because at these distances gravitational accelerations inhibit satellite formation. The best known exceptions are Jupiter's gossamer rings and Saturn's E ring, broad sheets of dust that extend outward until they fade from view at five to ten planetary radii. Source satellites continuously supply the dust, which is subsequently lost in collisions or by radial transport. Here we report that Saturn has an enormous ring associated with its outer moon Phoebe, extending from at least 128R(S) to 207R(S) (Saturn's radius R(S) is 60,330 km). The ring's vertical thickness of 40R(S) matches the range of vertical motion of Phoebe along its orbit. Dynamical considerations argue that these ring particles span the Saturnian system from the main rings to the edges of interplanetary space. The ring's normal optical depth of approximately 2 x 10(-8) is comparable to that of Jupiter's faintest gossamer ring, although its particle number density is several hundred times smaller. Repeated impacts on Phoebe, from both interplanetary and circumplanetary particle populations, probably keep the ring populated with material. Ring particles smaller than centimetres in size slowly migrate inward and many of them ultimately strike the dark leading face of Iapetus.

  14. Jupiter Ring Halo

    NASA Image and Video Library

    1998-03-26

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (km) per picture element (pixel) along the rings; however, because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow peering back toward the Sun; the ring was approximately 2,300,000 kilometers (km) away. The arc on the far right of the image is produced by sunlight scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age. Jupiter's ring system is composed of three parts -- a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, which lies exterior to the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the far left side of the figure. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow. A faint mist of particles can be seen above and below the main rings; this vertically extended, toroidal "halo" is unusual in planetary rings, and is probably caused by electromagnetic forces which can push small grains out of the ring plane. Halo material is present across this entire image, implying that it reaches more than 27,000 km above the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic. In order to accentuate faint features in the image, different brightnesses are shown through color, with the brightest being white or yellow and the faintest purple. http://photojournal.jpl.nasa.gov/catalog/PIA00658

  15. Validation of a portable, waterproof blood pH analyser for elasmobranchs

    PubMed Central

    Bouyoucos, Ian A.; Shipley, Oliver; Rummer, Jodie L.; Mandelman, John W.; Brooks, Edward J.; Grubbs, R. Dean

    2017-01-01

    Abstract Quantifying changes in blood chemistry in elasmobranchs can provide insights into the physiological insults caused by anthropogenic stress, and can ultimately inform conservation and management strategies. Current methods for analysing elasmobranch blood chemistry in the field are often costly and logistically challenging. We compared blood pH values measured using a portable, waterproof pH meter (Hanna Instruments HI 99161) with blood pH values measured by an i-STAT system (CG4+ cartridges), which was previously validated for teleost and elasmobranch fishes, to gauge the accuracy of the pH meter in determining whole blood pH for the Cuban dogfish (Squalus cubensis) and lemon shark (Negaprion brevirostris). There was a significant linear relationship between values derived via the pH meter and the i-STAT for both species across a wide range of pH values and temperatures (Cuban dogfish: 6.8–7.1 pH 24–30°C; lemon sharks: 7.0–7.45 pH 25–31°C). The relative error in the pH meter's measurements was ~±2.7%. Using this device with appropriate correction factors and consideration of calibration temperatures can result in both a rapid and accurate assessment of whole blood pH, at least for the two elasmobranch species examined here. Additional species should be examined in the future across a wide range of temperatures to determine whether correction factors are universal. PMID:28616238

  16. [Freedom in a little box].

    PubMed

    Lie, A K

    1999-04-20

    What are the implications for health of freedom as a community value? This article focuses on the fact that both health and freedom are complex concepts that elude a concise definition. Depending on how you define them, the answer to the question above will vary. Different conceptions of health and freedom are described initially, and then their interdependence is illustrated by means of examples. One issue examined is how the breakdown of the communist regime in the former Soviet Union influenced life expectancy, another the positive and negative aspects of the Cuban health system. Finally, the importance of a questioning attitude to the two concepts is underlined.

  17. Health Care in Modern Cuba

    PubMed Central

    Campos-Outcalt, Douglas; Janoff, Edward

    1980-01-01

    An extensively organized, centrally controlled system, aimed at equalizing and improving the distribution and quality of medical services according to population and geography, characterizes the modern Cuban health care complex. Facilities of increasing sophistication are located in urban areas while an expanding series of ambulatory, multipotential polyclinics attempts to provide most health services in both urban and rural settings. Maternal and child care, immunization programs and other forms of preventive medicine represent major priorities for expenditures. Occupational health is increasingly understood as a valuable resource, and medical professionals on all levels are being trained in significant numbers for Cuba and its allies. ImagesFigure 1.Figure 2.Figure 3. PMID:7376666

  18. Ring-laser gyroscope system using dispersive element(s)

    NASA Technical Reports Server (NTRS)

    Smith, David D. (Inventor)

    2010-01-01

    A ring-laser gyroscope system includes a ring-laser gyroscope (RLG) and at least one dispersive element optically coupled to the RLG's ring-shaped optical path. Each dispersive element has a resonant frequency that is approximately equal to the RLG's lasing frequency. A group index of refraction defined collectively by the dispersive element(s) has (i) a real portion that is greater than zero and less than one, and (ii) an imaginary portion that is less than zero.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Delamare, Jeffrey E

    2003-06-20

    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 aroundmore » 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.« less

  20. Telecommunications technology as an aid to family caregivers of persons with dementia.

    PubMed

    Czaja, Sara J; Rubert, Mark P

    2002-01-01

    The aging of the population implies that an increased number of people are going to need some form of care or assistance. Caregiving poses a range of physical, emotional, and financial demands and often causes burden and stress for family members. This article describes how technology can be used to provide support to caregivers and increase the quality of life for both caregivers and care recipients. Preliminary data from an ongoing study of dementia caregivers is provided to demonstrate the feasibility of using technological interventions for this population. The intervention involves a telecommunications system designed to augment a family therapy intervention by enhancing access to formal and informal support services. Specifically the system is intended to facilitate linkages between caregivers and other family members, friends, and other caregivers as well as to facilitate access to information on available resources. A total of 76 caregivers of dementia patients, including Cuban American and white American caregivers, received the telecommunications intervention. Data include real-time usage data and measures of usability at 6 months, 12 months, and 18 months after the initiation of the intervention. The data reported in this article are based on responses to the usability questionnaire at 6 months from a sample of 44 caregivers. Overall the results indicate that the system is easy to use and the caregivers find it valuable. The most common reason that the caregivers use the system is to communicate with other caregivers, especially those who are not nearby. The caregivers, especially the Cuban Americans, reported that the system facilitated their ability to communicate with family members and their therapist. The caregivers also indicated that they found participation in the "online discussion" groups to be very valuable and also found the "online resource guide"useful. The results demonstrate how current information and communication technologies can be used to help caregivers meet the challenges of caregiving and improve the quality of life for caregivers. The potential benefit of this type of technology for health care providers is also discussed.

  1. Configuration maintaining control of three-body ring tethered system based on thrust compensation

    NASA Astrophysics Data System (ADS)

    Huang, Panfeng; Liu, Binbin; Zhang, Fan

    2016-06-01

    Space multi-tethered systems have shown broad prospects in remote observation missions. This paper mainly focuses on the dynamics and configuration maintaining control of space spinning three-body ring tethered system for such mission. Firstly, we establish the spinning dynamic model of the three-body ring tethered system considering the elasticity of the tether using Newton-Euler method, and then validate the suitability of this model by numerical simulation. Subsequently, LP (Likins-Pringle) initial equilibrium conditions for the tethered system are derived based on rigid body's equilibrium theory. Simulation results show that tether slack, snapping and interaction between the tethers exist in the three-body ring system, and its' configuration can not be maintained without control. Finally, a control strategy based on thrust compensation, namely thrust to simulate tether compression under LP initial equilibrium conditions is designed to solve the configuration maintaining control problem. Control effects are verified by numerical simulation compared with uncontrolled situation. Simulation results show that the configuration of the three-body ring tethered system could maintain under this active control strategy.

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

    NASA Astrophysics Data System (ADS)

    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.

  3. Genetic origin, admixture, and asymmetry in maternal and paternal human lineages in Cuba

    PubMed Central

    2008-01-01

    Background Before the arrival of Europeans to Cuba, the island was inhabited by two Native American groups, the Tainos and the Ciboneys. Most of the present archaeological, linguistic and ancient DNA evidence indicates a South American origin for these populations. In colonial times, Cuban Native American people were replaced by European settlers and slaves from Africa. It is still unknown however, to what extent their genetic pool intermingled with and was 'diluted' by the arrival of newcomers. In order to investigate the demographic processes that gave rise to the current Cuban population, we analyzed the hypervariable region I (HVS-I) and five single nucleotide polymorphisms (SNPs) in the mitochondrial DNA (mtDNA) coding region in 245 individuals, and 40 Y-chromosome SNPs in 132 male individuals. Results The Native American contribution to present-day Cubans accounted for 33% of the maternal lineages, whereas Africa and Eurasia contributed 45% and 22% of the lineages, respectively. This Native American substrate in Cuba cannot be traced back to a single origin within the American continent, as previously suggested by ancient DNA analyses. Strikingly, no Native American lineages were found for the Y-chromosome, for which the Eurasian and African contributions were around 80% and 20%, respectively. Conclusion While the ancestral Native American substrate is still appreciable in the maternal lineages, the extensive process of population admixture in Cuba has left no trace of the paternal Native American lineages, mirroring the strong sexual bias in the admixture processes taking place during colonial times. PMID:18644108

  4. Quality of Life of People With HIV/AIDS Receiving Antiretroviral Therapy in Cuba: A Cross-Sectional Study of the National Population

    PubMed Central

    Aragonés-López, Carlos; Pérez-Ávila, Jorge; Smith Fawzi, Mary C.

    2012-01-01

    Objectives. We studied the effect of antiretroviral therapy (ART) on the quality of life (QOL) of Cubans with HIV/AIDS. Methods. We conducted a cross-sectional study including administration of the Medical Outcomes Study–HIV Health Survey Questionnaire to a representative sample of the 1592 Cubans receiving ART in 2004. For univariate analyses, we compared mean HIV scale scores. We used logistic regression models to estimate the association between role function and year of diagnosis, between pain and sex, and between health transition and region of diagnosis, with adjustment for demographics, ART regimen, and clinical status. Results. There were 354 participants (73 women, 281 men). Scores for all functional activities showed means higher than 80 out of 100. Pain interfered more in women than in men (73.2 vs 81.9; P = .01). When HIV diagnosis occurred after 2001, the probability of experiencing difficulties performing work (odds ratio [OR] = 4.42; 95% CI = 1.83, 10.73) and pain (OR = 1.70; 95% CI = 1.01, 2.88) increased compared with earlier diagnosis. People treated with indinavir showed a greater perception of general health (58.9 vs 52.4; P = .045) and greater health improvement (78.6 vs 67.8; P = .002). Conclusions. Although Cubans receiving ART are maintaining a high QOL, we observed significant differences by sex and time of diagnosis. QOL assessment can serve as a health outcome and may allow identification of QOL reductions potentially related to ART side effects. PMID:22420793

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

    PubMed Central

    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

  6. Prevalence and genotype distribution of Pneumocystis jirovecii in Cuban infants and toddlers with whooping cough.

    PubMed

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

    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.

  7. A measuring tool for tree-rings analysis

    NASA Astrophysics Data System (ADS)

    Shumilov, Oleg; Kanatjev, Alexander; Kasatkina, Elena

    2013-04-01

    A special tool has been created for the annual tree-ring widths measurement and analysis. It consists of professional scanner, computer system and software. This created complex in many aspects does not yield the similar systems (LINTAB, WinDENDRO), but in comparison to manual measurement systems, it offers a number of advantages: productivity gain, possibility of archiving the results of the measurements at any stage of the processing, operator comfort. It has been developed a new software, allowing processing of samples of different types (cores, saw cuts), including those which is difficult to process, having got a complex wood structure (inhomogeneity of growing in different directions, missed, light and false rings etc.). This software can analyze pictures made with optical scanners, analog or digital cameras. The complex software program was created on programming language C++, being compatible with modern operating systems like Windows X. Annual ring widths are measured along paths traced interactively. These paths can have any orientation and can be created so that ring widths are measured perpendicular to ring boundaries. A graphic of ring-widths in function of the year is displayed on a screen during the analysis and it can be used for visual and numerical cross-dating and comparison with other series or master-chronologies. Ring widths are saved to the text files in a special format, and those files are converted to the format accepted for data conservation in the International Tree-Ring Data Bank. The created complex is universal in application that will allow its use for decision of the different problems in biology and ecology. With help of this complex it has been reconstructed a long-term juniper (1328-2004) and pine (1445-2005) tree-ring chronologies on the base of samples collected at Kola Peninsula (northwestern Russia).

  8. Transfer matrix approach to the persistent current in quantum rings: Application to hybrid normal-superconducting rings

    NASA Astrophysics Data System (ADS)

    Nava, Andrea; Giuliano, Rosa; Campagnano, Gabriele; Giuliano, Domenico

    2016-11-01

    Using the properties of the transfer matrix of one-dimensional quantum mechanical systems, we derive an exact formula for the persistent current across a quantum mechanical ring pierced by a magnetic flux Φ as a single integral of a known function of the system's parameters. Our approach provides exact results at zero temperature, which can be readily extended to a finite temperature T . We apply our technique to exactly compute the persistent current through p -wave and s -wave superconducting-normal hybrid rings, deriving full plots of the current as a function of the applied flux at various system's scales. Doing so, we recover at once a number of effects such as the crossover in the current periodicity on increasing the size of the ring and the signature of the topological phase transition in the p -wave case. In the limit of a large ring size, resorting to a systematic expansion in inverse powers of the ring length, we derive exact analytic closed-form formulas, applicable to a number of cases of physical interest.

  9. Collisional and dynamical processes in moon and planet formation

    NASA Technical Reports Server (NTRS)

    Chapman, C. R.; Davis, D. R.; Weidenschilling, S. J.; Hartmann, W. K.; Spaute, D.

    1987-01-01

    Research on a variety of dynamical processes relevant to the formation of planets, satellites and ring systems is discussed. The main focus is on studies of accretionary formation of early protoplanets using a numerical model, structures and evolution of ring systems and individual bodies within planetary rings, and theories of lunar origin.

  10. Far Away from the Revolution: Understanding the Cuban Revolutionary Armed Forces Mission Changes

    DTIC Science & Technology

    2011-12-01

    municipalities), Plan for Entrepreneurial Redesign, CIMEX (import/export, free-trade zones, tourism, transportation, digital communications equipment, car...rentals and audiovisual publicity), CUBANA-CAN (similar to CIMEX ), Citrus (agricultural and industrial processing), State Commission for

  11. 31 CFR 515.522 - U.S. assets of certain Cuban decedents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... section that is not written in the English language must be accompanied by a translation into English, as... qualified to make the translation, and has made an accurate translation of the document in question. [54 FR...

  12. 33 CFR 107.200 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... United States; or (iv) A corporation, partnership, association, trust, joint venture, limited liability company, limited liability partnership, or any other legal entity, created and authorized to own vessels... NATIONAL VESSEL AND FACILITY CONTROL MEASURES AND LIMITED ACCESS AREAS Unauthorized Entry Into Cuban...

  13. Cuban Telecommunications, Computer Networking, and U.S. Policy Implications,

    DTIC Science & Technology

    1996-07-01

    Informacion para la Prensa Federacion de Mujeres Cubanas Grupo para la Educacion sobre el SIDA Instituto Superior Latinoamericano de Ajedrez...DIR) Informacion sobre Medio Ambiente (DIR) Medicina Alternativa (DIR) Servicio Especial de la Mujer (DIR) Eventos Internacionales (DIR

  14. New synonymy in Cuban Tilloclytus (Coleoptera: Cerambycidae: Anaglyptini)

    USDA-ARS?s Scientific Manuscript database

    Examination of holotypes of Tilloclytus (Coleoptera: Cerambycidae: Anaglyptini) in the Fernando de Zayas collection (Havana, Cuba) and the Museum of Comparative Zoology, Harvard University reveals that T. elongatus Zayas (1975) is a new synonym of T. rufipes Fisher (1942)....

  15. Warden’s Five-Ring System Theory: Legitimate Wartime Military Targeting or an Increased Potential to Violate the Law and Norms of Expected Behavior?

    DTIC Science & Technology

    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.

  16. A pulsed jumping ring apparatus for demonstration of Lenz's law

    NASA Astrophysics Data System (ADS)

    Tanner, Paul; Loebach, Jeff; Cook, James; Hallen, H. D.

    2001-08-01

    Lenz's law is often demonstrated in classrooms by the use of Elihu Thomson's jumping ring. However, it is ironic that a thorough analysis of the physics of the ac jumping ring reveals that the operation is due mainly to a phase difference, not Lenz's law. A complete analysis of the physics behind the ac jumping ring is difficult for the introductory student. We present a design for a pulsed jumping ring which can be fully described by the application of Lenz's law. Other advantages of this system are that it lends itself to a rigorous analysis of the force balances and energy flow. The simple jumping ring apparatus closely resembles Thomson's, but is powered by a capacitor bank. The jump heights were measured for several rings as a function of energy stored in the capacitors. A simple model describes the data well. Currents in both the drive coil and ring are measured and that of the drive coil modeled to illuminate some properties of the capacitors. An analysis of the energy flow in the system explains the higher jump heights, to 2 m, when the ring is cooled.

  17. Passive Vibration Control of Airborne Equipment using a Circular Steel Ring

    NASA Technical Reports Server (NTRS)

    Ellison, Joseph; Ahmadi, Goodarz; Kehoe, Mike

    1997-01-01

    Vibration isolation is needed to protect avionics equipment from adverse aircraft vibration environments. Passive isolation is the simplest means to achieve this goal. The system used here consists of a circular steel ring with a lump mass on top and exposed to base excitation. Sinusoidal and filtered zero-mean Gaussian white noise are used to excite the structure and the acceleration response spectra at the top of the ring are computed. An experiment is performed to identify the natural frequencies and modal damping of the circular ring. Comparison is made between the analytical and experimental results and good agreement is observed. The ring response is also evaluated with a concentrated mass attached to the top of the ring. The effectiveness of the ring in isolating the equipment from base excitation is studied. The acceleration response spectra of a single degree of freedom system attached to the top of the ring are evaluated and the results are compared with those exposed directly to the base excitation. It is shown that a properly designed ring could effectively protect the avionics from possible damaging excitation levels.

  18. Compositional Evolution of Saturn's Rings Due to Meteoroid Bombardment

    NASA Technical Reports Server (NTRS)

    Cuzzi, J.; Estrada, P.; Young, Richard E. (Technical Monitor)

    1997-01-01

    In this paper we address the question of compositional evolution in planetary ring systems subsequent to meteoroid bombardment. The huge surface area to mass ratio of planetary rings ensures that this is an important process, even with current uncertainties on the meteoroid flux. We develop a new model which includes both direct deposition of extrinsic meteoritic "pollutants", and ballistic transport of the increasingly polluted ring material as impact ejecta. Our study includes detailed radiative transfer modeling of ring particle spectral reflectivities based on refractive indices of realistic constituents. Voyager data have shown that the lower optical depth regions in Saturn's rings (the C ring and Cassini Division) have darker and less red particles than the optically thicken A and B rings. These coupled structural-compositional groupings have never been explained; we present and explore the hypothesis that global scale color and compositional differences in the main rings of Saturn arise naturally from extrinsic meteoroid bombardment of a ring system which was initially composed primarily, but not entirely, of water ice. We find that the regional color and albedo differences can be understood if all ring material was initially identical (primarily water ice, based on other data, but colored by tiny amounts of intrinsic reddish, plausibly organic, absorber) and then evolved entirely by addition and mixing of extrinsic, nearly neutrally colored. plausibly carbonaceous material. We further demonstrate that the detailed radial profile of color across the abrupt B ring - C ring boundary can.constrain key unknown parameters in the model. Using new alternates of parameter values, we estimate the duration of the exposure to extrinsic meteoroid flux of this part of the rings, at least, to be on the order of 10(exp 8) years. This conclusion is easily extended by inference to the Cassini Division and its surroundings as well. This geologically young "age" is compatible with timescales estimated elsewhere based on the evolution of ring structure due to ballistic transport, and also with other "short timescales" estimated on the grounds of gravitational torques. However, uncertainty in the flux of interplanetary debris and in the ejects yield may preclude ruling out a ring age as old as the solar system at this time.

  19. Differential Calculus on h-Deformed Spaces

    NASA Astrophysics Data System (ADS)

    Herlemont, Basile; Ogievetsky, Oleg

    2017-10-01

    We construct the rings of generalized differential operators on the h-deformed vector space of gl-type. In contrast to the q-deformed vector space, where the ring of differential operators is unique up to an isomorphism, the general ring of h-deformed differential operators {Diff}_{h},σ(n) is labeled by a rational function σ in n variables, satisfying an over-determined system of finite-difference equations. We obtain the general solution of the system and describe some properties of the rings {Diff}_{h},σ(n).

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

    NASA Astrophysics Data System (ADS)

    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.

  1. Simulating the Smallest Ring World of Chariklo

    NASA Astrophysics Data System (ADS)

    Michikoshi, Shugo; Kokubo, Eiichiro

    2017-03-01

    A ring system consisting of two dense narrow rings has been discovered around Centaur Chariklo. The existence of these rings around a small object poses various questions about their origin, stability, and lifetime. In order to understand the nature of Chariklo’s rings, we perform global N-body simulations of the self-gravitating collisional particle rings for the first time. We find that Chariklo should be denser than the ring material in order to avoid the rapid diffusion of the rings. If Chariklo is denser than the ring material, fine spiral structures called self-gravity wakes occur in the inner ring. These wakes accelerate the viscous spreading of the ring significantly and typically occur on timescales of about 100 {years} for m-sized ring particles, which is considerably shorter than the timescales suggested in previous studies. The existence of these narrow rings implies smaller ring particles or the existence of shepherding satellites.

  2. Multiple internal seal ring micro-electro-mechanical system vacuum packaging method

    NASA Technical Reports Server (NTRS)

    Hayworth, Ken J. (Inventor); Yee, Karl Y. (Inventor); Shcheglov, Kirill V. (Inventor); Bae, Youngsam (Inventor); Wiberg, Dean V. (Inventor); Challoner, A. Dorian (Inventor); Peay, Chris S. (Inventor)

    2008-01-01

    A Multiple Internal Seal Ring (MISR) Micro-Electro-Mechanical System (MEMS) vacuum packaging method that hermetically seals MEMS devices using MISR. The method bonds a capping plate having metal seal rings to a base plate having metal seal rings by wafer bonding the capping plate wafer to the base plate wafer. Bulk electrodes may be used to provide conductive paths between the seal rings on the base plate and the capping plate. All seals are made using only metal-to-metal seal rings deposited on the polished surfaces of the base plate and capping plate wafers. However, multiple electrical feed-through metal traces are provided by fabricating via holes through the capping plate for electrical connection from the outside of the package through the via-holes to the inside of the package. Each metal seal ring serves the dual purposes of hermetic sealing and providing the electrical feed-through metal trace.

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

    NASA Astrophysics Data System (ADS)

    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.

  4. Uncovering a new Uranus ring-moon connection in 25 years of occultation data

    NASA Astrophysics Data System (ADS)

    Chancia, R. O.; Hedman, M. M.; French, R. G.

    2017-12-01

    The Uranus ring-moon system consists of 10 narrow and dense main rings, 3 broad diffuse and dusty rings, and 13 small inner moons. Nine of these moons, dubbed the `Portia group', orbit within a radial range of less than 20,000 km, making them the most tightly packed system of moons in our solar system. For the first time, we have constrained the mass of one of the inner moons by measuring its gravitational influence on the η ring. The η ring is one of the narrow rings of Uranus, consisting of a dense core that is 1-2 km wide and a diffuse outer sheet spanning about 40 km. Its dense core lies just exterior to the 3:2 Inner Lindblad Resonance of the small moon Cressida. We fit the η ring radius residuals and longitudes from a complete set of both ground-based and Voyager stellar and radio occultations of the Uranian rings spanning 1977-2002. We find variations in the radial position of the η ring that are likely generated by this resonance, and take the form of a 3-lobed structure rotating at an angular rate equal to the mean motion of the moon Cressida. The amplitude of these radial oscillations is 0.667 ± 0.113 km, which is consistent with the expected shape due to the perturbations of Cressida. The magnitude of these variations provides the first measurement of the mass and density of the moon Cressida or, indeed, any of Uranus' small inner moons. The system has previously been simulated over a wide range of presumed masses and is found to be dynamically unstable, with the next collision most likely occurring in less than a few million years. Two of the broad dusty rings orbit in range of the moons and may be evidence of collisions in the recent past. A better grasp of inner Uranian satellite masses will provide another clue to the composition, dynamical stability, and history of this tightly packed system of moons.

  5. Electro-optical hybrid slip ring

    NASA Astrophysics Data System (ADS)

    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. A laboratory scale non-contact Electro-Optical Hybrid Slip Ring system was successfully constructed, and its performance was determined. Experimental results affirmed the advantages of this new technology over current slip ring design.

  6. Alstom Francis Turbine Ring Gates: from Retrofitting to Commissioning

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  9. Cavity-locked ring down spectroscopy

    DOEpatents

    Zare, Richard N.; Paldus, Barbara A.; Harb, Charles C.; Spence, Thomas

    2000-01-01

    Distinct locking and sampling light beams are used in a cavity ring-down spectroscopy (CRDS) system to perform multiple ring-down measurements while the laser and ring-down cavity are continuously locked. The sampling and locking light beams have different frequencies, to ensure that the sampling and locking light are decoupled within the cavity. Preferably, the ring-down cavity is ring-shaped, the sampling light is s-polarized, and the locking light is p-polarized. Transmitted sampling light is used for ring-down measurements, while reflected locking light is used for locking in a Pound-Drever scheme.

  10. Immigrant Aspirations

    ERIC Educational Resources Information Center

    Portes, Alejandro; And Others

    1978-01-01

    Examines occupational, income, and educational aspirations among recent Mexican and Cuban immigrants to the United States. Aspirations appear to be set through a rational assessment of past attainments and skills. Reviews implications for immigrants'"dreams of fantasy" when they first arrive in the United States. (Author/AV)

  11. 75 FR 82200 - Expansion of Global Entry Pilot to Mexican Nationals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-29

    ..., firearms, mace, pepper spray, endangered animals, birds, controlled substances, fireworks, Cuban goods, and... Airport, Chicago, Illinois (ORD); and Miami International Airport, Miami, Florida (MIA). Additionally, on... Francisco, California (SFO); Orlando International Airport, Orlando, Florida (MCO); Detroit Metropolitan...

  12. Hispanic American Diversity.

    ERIC Educational Resources Information Center

    Zavaleta, Antonio N.; And Others

    1981-01-01

    This issue of the Hispanic Research Center's journal contains three articles which explore diversity among Hispanic American groups (Puerto Ricans, Cubans, and Mexicans) in health status, family structure, and socioeconomic characteristics. In the lead article, "Variations in Hispanic Health Status," Antonio Zavaleta examines differences in…

  13. The African Heritage in Spanish Caribbean Literature.

    ERIC Educational Resources Information Center

    Smart, Ian I.

    1981-01-01

    Uses Fanon's concept of the Manichean colonial situation and his Dialectical Theory of Identification to explore images of African heritage in the works of two mulatto Cuban poets, Gabriel de la Concepcion Valdez (1809-1844) and Nicolas Guillen (born 1902). (GC)

  14. National Synchrotron Light Source II storage ring vacuum systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hseuh, Hsiao-Chaun, E-mail: hseuh@bnl.gov; Hetzel, Charles; Leng, Shuwei

    2016-05-15

    The National Synchrotron Light Source II, completed in 2014, is a 3-GeV synchrotron radiation (SR) facility at Brookhaven National Laboratory and has been in steady operation since. With a design electron current of 500 mA and subnanometer radians horizontal emittance, this 792-m circumference storage ring is providing the highest flux and brightness x-ray beam for SR users. The majority of the storage ring vacuum chambers are made of extruded aluminium. Chamber sections are interconnected using low-impedance radiofrequency shielded bellows. SR from the bending magnets is intercepted by water-cooled compact photon absorbers resided in the storage ring chambers. This paper presents themore » design of the storage ring vacuum system, the fabrication of vacuum chambers and other hardware, the installation, the commissioning, and the continuing beam conditioning of the vacuum systems.« less

  15. The LEO Archipelago: A system of earth-rings for communications, mass-transport to space, solar power, and control of global warming

    NASA Astrophysics Data System (ADS)

    Meulenberg, Andrew; Karthik Balaji, P. S.

    2011-06-01

    Man's quest to get into space is hindered by major problems (e.g., system-development and capital costs, expense of putting mass into orbit, trapped-radiation belts, and environmental impact of a large increase in rocket launches). A multi-purpose low-earth-orbit system of rings circling the earth - the "LEO ARCHIPELAGO TM" - is proposed as a means of solving or bypassing many of them. A fiber-optic ring about the earth would be an initial testing and developmental stage for the Ring Systems, while providing cash-flow through a LEO-based, high-band-width, world-wide communication system. A low-earth-orbit-based space-elevator system, "Sling-on-a-Ring TM", is proposed as the crucial developmental stage of the LEO Archipelago. Being a LEO-based heavy-mass lifter, rather than earth- or GEO-based, it is much less massive and therefore less costly than other proposed space-elevators. With the advent of lower-cost, higher-mass transport to orbit, the options for further space development (e.g., space solar power, radiation, and space-debris dampers, sun shades, and permanent LEO habitation) are greatly expanded. This paper provides an update of the Sling-on-a-Ring concept in terms of new materials, potential applications, and trade-offs associated with an earlier model. The impact of Colossal Carbon Tubes, CCT, a new material with high tensile strength, extremely-low density, and other favorable properties, and other new technologies (e.g., solar-powered lasers, power beaming to near-space and earth, and thermal-control systems) on the development of associated LEO-Ring systems is also explored. The material's effect on the timeline for the system development indicates the feasibility of near-term implementation of the system (possibly within the decade). The Sling-on-a-Ring can provide a less-expensive, environment-friendly mode of access to space. This would pave the way (via eventual operation at >1000 t per day by 2050) for large scale development of space-based technologies.

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

    NASA Astrophysics Data System (ADS)

    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 Horizons. Elsewhere in the solar system, small moons commonly share their orbits with faint dust rings. Our results support recent dynamical studies suggesting that small grains are quickly lost from the Pluto-Charon system due to solar radiation pressure, whereas larger particles are orbitally unstable due to ongoing perturbations by the known moons.

  17. A numerical investigation into the dynamics of Uranus' mu-ring

    NASA Astrophysics Data System (ADS)

    Kumar, K.; De Pater, I.; Showalter, M.

    2017-12-01

    Showalter and Lissauer (2006) reported the discovery of the nu-ring and mu-ring, located beyond Uranus' main ring system. Both faint, dusty rings are located interior to the large classical moons and were observed by co-adding Hubble Space Telescope (HST) images. The peak radial brightness of the mu-ring coincides with the orbit of Mab, a small moon discovered in 2003 by Showalter and Lissauer. Observations of the Mab/mu-ring system indicate a highly dynamic environment. The motion of Mab was determined to be anomalous over short time scales, with large position deviations computed with respect to a fitted precessing Keplerian ellipse. Numerical simulations to survey the possible cause of this anomalous motion hint at the possibility of interactions with a distribution of tens of bodies, below the HST detection threshold, in the neighborhood of Mab (Kumar, et al., 2016). Analysis of the mu-ring data has led to the discovery of peculiar features, leading to open questions about dust dynamics in the associated region around Uranus. Observations obtained using the HST and Keck telescopes reveal that the μ-ring is blue, indicative of a pre-dominance of sub-micron-sized particles (de Pater, et al., 2006). The only other blue ring detected in the Solar System is Saturn's E-ring, generated by plumes on Enceladus' south pole. The origin of the mu-ring however remains an open area of research. Mab is thought to be the likely source of the material in the mu-ring, with micrometeoroid impacts releasing material into orbit around Uranus, much like Jupiter's faint rings are regenerated by companion (small) moons (Burns et al. 1999). The mu-ring's blue color suggests however that there is an unknown mechanism at play that hides or removes large particles from the expected size distribution. We present results from a numerical investigation into the effects of gravitational and non-gravitational forces on the evolution of mu-ring dust particles. Following on from previous studies (Sfair and Giuliatti Winter, 2009; Sfair and Giuliatti Winter, 2012; Sfair, 2013; Hsu, et al., 2014), we generate statistics to provide insight into the lifetime of mu-ring dust. We utilize these results to analyze the possibility that the steep size distribution results from size-based sorting effects due to the natural environment.

  18. Saturn's Rings, the Yarkovsky Effects, and the Ring of Fire

    NASA Technical Reports Server (NTRS)

    Rubincam, David Parry

    2004-01-01

    The dimensions of Saturn's A and B rings may be determined by the seasonal Yarkovsky effect and the Yarkovsky-Schach effect; the two effects confine the rings between approximately 1.68 and approximately 2.23 Saturn radii, in reasonable agreement with the observed values of 1.525 and 2.267. The C ring may be sparsely populated because its particles are transients on their way to Saturn; the infall may create a luminous Ring of Fire around Saturn's equator. The ring system may be young: in the past heat flow from Saturn's interior much above its present value would not permit rings to exist.

  19. Cluster Inter-Spacecraft Communications

    NASA Technical Reports Server (NTRS)

    Cox, Brian

    2008-01-01

    A document describes a radio communication system being developed for exchanging data and sharing data-processing capabilities among spacecraft flying in formation. The system would establish a high-speed, low-latency, deterministic loop communication path connecting all the spacecraft in a cluster. The system would be a wireless version of a ring bus that complies with the Institute of Electrical and Electronics Engineers (IEEE) standard 1393 (which pertains to a spaceborne fiber-optic data bus enhancement to the IEEE standard developed at NASA's Jet Propulsion Laboratory). Every spacecraft in the cluster would be equipped with a ring-bus radio transceiver. The identity of a spacecraft would be established upon connection into the ring bus, and the spacecraft could be at any location in the ring communication sequence. In the event of failure of a spacecraft, the ring bus would reconfigure itself, bypassing a failed spacecraft. Similarly, the ring bus would reconfigure itself to accommodate a spacecraft newly added to the cluster or newly enabled or re-enabled. Thus, the ring bus would be scalable and robust. Reliability could be increased by launching, into the cluster, spare spacecraft to be activated in the event of failure of other spacecraft.

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

    NASA Astrophysics Data System (ADS)

    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.

  1. Ring lens focusing and push-pull tracking scheme for optical disk systems

    NASA Technical Reports Server (NTRS)

    Gerber, R.; Zambuto, J.; Erwin, J. K.; Mansuripur, M.

    1993-01-01

    An experimental comparison of the ring lens and the astigmatic techniques of generating focus-error-signal (FES) in optical disk systems reveals that the ring lens generates a FES over two times steeper than that produced by the astigmat. Partly due to this large slope and, in part, because of its diffraction-limited behavior, the ring lens scheme exhibits superior performance characteristics. In particular the undesirable signal known as 'feedthrough' (induced on the FES by track-crossings during the seek operation) is lower by a factor of six compared to that observed with the astigmatic method. The ring lens is easy to align and has reasonable tolerance for positioning errors.

  2. Charged dust in Saturn's magnetosphere

    NASA Technical Reports Server (NTRS)

    Mendis, D. A.; Hill, J. R.; Houpis, H. L. F.

    1983-01-01

    The overall distribution of fine dust in the Saturnian magnetosphere, its behavior, the cosmogony of the Saturnian ring system, and observations of the magnetosphere and ring system are synthesized and explained using gravito-electrodynamics. Among the phenomena discussed are the formation of waves in the F-ring, the cause of eccentricities of certain isolated ringlets, and the origin and morphology of the broad diffuse E-ring. Magnetogravitational resonance of charged dust with nearby satellites, gyro-orbital resonances, and magnetogravitational capture of exogenic dust by the magnetosphere are used to explain individual observations. The effect of a ring current associated with the charged dust is evaluated. Finally, the cosmogonic implications of the magnetogravitational theory are discussed.

  3. Bushing retention system for thermal medium cooling delivery tubes in a gas turbine rotor

    DOEpatents

    Mashey, Thomas Charles

    2002-01-01

    Bushings are provided in counterbores for wheels and spacers for supporting thermal medium cooling tubes extending axially adjacent the rim of the gas turbine rotor. The retention system includes a retaining ring disposed in a groove adjacent an end face of the bushing and which retaining ring projects radially inwardly to prevent axial movement of the bushing in one direction. The retention ring has a plurality of circumferentially spaced tabs along its inner diameter whereby the ring is supported by the lands of the tube maintaining its bushing retention function, notwithstanding operation in high centrifugal fields and rotation of the ring in the groove into other circular orientations.

  4. Reactor vessel support system. [LMFBR

    DOEpatents

    Golden, M.P.; Holley, J.C.

    1980-05-09

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  5. Container lid gasket protective strip for double door transfer system

    DOEpatents

    Allen, Jr., Burgess M

    2013-02-19

    An apparatus and a process for forming a protective barrier seal along a "ring of concern" of a transfer container used with double door systems is provided. A protective substrate is supplied between a "ring of concern" and a safety cover in which an adhesive layer of the substrate engages the "ring of concern". A compressive foam strip along an opposite side of the substrate engages a safety cover such that a compressive force is maintained between the "ring of concern" and the adhesive layer of the substrate.

  6. Uranus and the shape of elliptical rings

    NASA Technical Reports Server (NTRS)

    Lucke, R. L.

    1978-01-01

    It is reported that when the star SAO158687 passed behind the Uranus system, its light was occulted twice by the epsilon (fifth) ring of the planet. The first part of the ring to occult was about 100 km wide and the second part was about 40 km wide. The variable width of the ring is accounted for by differences in the orbital eccentricities of the individual particles composing the ring.

  7. AXAF VETA-I mirror ring focus measurements

    NASA Technical Reports Server (NTRS)

    Tananbaum, H. D.; Zhao, P.

    1994-01-01

    The AXAF VETA-I mirror ring focus measurements were made with an HRI (microchannel plate) X-ray detector. The ring focus is a sharply focused ring formed by X-rays before they reach the VEAT-I focal plane. It is caused by spherical aberrations due to the finite source distance and the despace in the VETA-I test. The ring focus test reveals some aspects fo the test system distortions and the mirror surface figure which are difficult or impossible to detect at the focal plane. The test results show periodic modulations of the ring radius and width which could be caused by gravity, thermal, and/or epoxy shrinkage distortions. The strongest component of the modulation had a 12-fold symmetry, because these distortions were exerted on the mirror through 12 flexures of the VETA-I mount. Ring focus models were developed to simulate the ring image. The models were compared with the data to understand the test system distortions and the mirror glass imperfection. Further studies will be done to complete this work. The ring focus measurement is a very powerful test. We expect that a similar test for the finally assembled mirror of AXAD-I will be highly valuable.

  8. Method of lining a vertical mine shaft with concrete

    DOEpatents

    Eklund, James D.; Halter, Joseph M.; Rasmussen, Donald E.; Sullivan, Robert G.; Moffat, Robert B.

    1981-01-01

    The apparatus includes a cylindrical retainer form spaced inwardly of the wall of the shaft by the desired thickness of the liner to be poured and having overlapping edges which seal against concrete flow but permit the form to be contracted to a smaller circumference after the liner has hardened and is self-supporting. A curb ring extends downwardly and outwardly toward the shaft wall from the bottom of the retainer form to define the bottom surface of each poured liner section. An inflatable toroid forms a seal between the curb ring and the shaft wall. A form support gripper ring having gripper shoes laterally extendable under hydraulic power to engage the shaft wall supports the retainer form, curb ring and liner until the newly poured liner section becomes self-supporting. Adjusting hydraulic cylinders permit the curb ring and retainer form to be properly aligned relative to the form support gripper ring. After a liner section is self-supporting, an advancing system advances the retainer form, curb ring and form support gripper ring toward a shaft boring machine above which the liner is being formed. The advancing system also provides correct horizontal alignment of the form support gripper ring.

  9. 75 FR 12000 - Unblocking of Specially Designated Nationals and Blocked Persons Pursuant to the Cuban Assets...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... unblocking and removal from the list of Specially Designated Nationals and Blocked Persons (``SDN list'') of...-hour fax-on-demand service at (202) 622-0077. Background On March 2, 2010, OFAC removed from the SDN...

  10. Thinking and Believing.

    ERIC Educational Resources Information Center

    Freie, John F.

    1987-01-01

    Critical thinking is seldom effective at encouraging students to challenge and examine preconceived positions. There is a tendency to use the rigorous questioning methods to defend preconceived positions and deflect the serious consideration of alternatives. An exercise that focused on the Cuban missile crisis is described. (MLW)

  11. A survey of Rocketry and astronautics in Spain

    NASA Technical Reports Server (NTRS)

    Maluquer, J. J.

    1977-01-01

    The entire field of rocketry and astronautics in Spain was studied. Congreve war rockets in military actions were emphasized in the African war, the Cuban campaign and the Spanish Civil War. Rockets in space travel were also summarized along with space science fiction.

  12. 78 FR 57223 - Continuation of the Exercise of Certain Authorities Under the Trading With the Enemy Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-17

    ... with respect to Cuba is in the national interest of the United States. Therefore, consistent with the..., 2014, the exercise of those authorities with respect to Cuba, as implemented by the Cuban Assets...

  13. The News about Hispanics.

    ERIC Educational Resources Information Center

    Russell, Cheryl

    1983-01-01

    Describes the geographic distribution, demographic characteristics, and consumer preferences of Puerto Ricans, Mexicans, and Cubans in the United States. Suggests that a projected rapid growth in numbers of Hispanics with unique characteristics will produce a consumer market that will require special attention from businesses. (Author/MJL)

  14. 31 CFR 515.543 - Proof of origin.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... of goods of Cuban origin are generally not issued unless the applicant submits satisfactory... constitute satisfactory proof varies depending upon the facts of the particular case, it is not possible to... satisfactory proof of origin. Independent corroborating documentary evidence, such as insurance documents...

  15. Conversacion sobre "Tres tristes tigres". Una entrevista de Rita Guibert (A Conversation about "Three Sad Tigers". An Interview with Rita Guibert)

    ERIC Educational Resources Information Center

    Cabrera Infante, Guillermo

    1971-01-01

    Interview took place in London, England, on October 5, 1970 between Cuban writer Guillermo Cabrera Infante and journalist Rita Guibert. Special issue dedicated to contemporary Spanish American literature. (DS)

  16. Finite element analysis to compare complete denture and implant-retained overdentures with different attachment systems.

    PubMed

    Barão, Valentim Adelino Ricardo; Assunção, Wirley Gonçalves; Tabata, Lucas Fernando; Delben, Juliana Aparecida; Gomes, Erica Alves; de Sousa, Edson Antonio Capello; Rocha, Eduardo Passos

    2009-07-01

    This finite element analysis compared stress distribution on complete dentures and implant-retained overdentures with different attachment systems. Four models of edentulous mandible were constructed: group A (control), complete denture; group B, overdenture retained by 2 splinted implants with bar-clip system; group C, overdenture retained by 2 unsplinted implants with o'ring system; and group D, overdenture retained by 2 splinted implants with bar-clip and 2 distally placed o'ring system. Evaluation was performed on Ansys software, with 100-N vertical load applied on central incisive teeth. The lowest maximum general stress value (in megapascal) was observed in group A (64.305) followed by groups C (119.006), D (258.650), and B (349.873). The same trend occurred in supporting tissues with the highest stress value for cortical bone. Unsplinted implants associated with the o'ring attachment system showed the lowest maximum stress values among all overdenture groups. Furthermore, o'ring system also improved stress distribution when associated with bar-clip system.

  17. RF System Requirements for a Medium-Energy Electron-Ion Collider (MEIC) at JLab

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rimmer, Robert A; Hannon, Fay E; Guo, Jiquan

    2015-09-01

    JLab is studying options for a medium energy electron-ion collider that could fit on the JLab site and use CEBAF as a full-energy electron injector. A new ion source, linac and booster would be required, together with collider storage rings for the ions and electrons. In order to achieve the maximum luminosity these will be high-current storage rings with many bunches. We present the high-level RF system requirements for the storage rings, ion booster ring and high-energy ion beam cooling system, and describe the technology options under consideration to meet them. We also present options for staging that might reducemore » the initial capital cost while providing a smooth upgrade path to a higher final energy. The technologies under consideration may also be useful for other proposed storage ring colliders or ultimate light sources.« less

  18. Transport electron through a quantum wire by side-attached asymmetric quantum-dot rings

    NASA Astrophysics Data System (ADS)

    Rostami, A.; Zabihi, S.; Rasooli S., H.; Seyyedi, S. K.

    2011-12-01

    The electronic conductance at zero temperature through a quantum wire with side-attached asymmetric quantum ring (as a scatter system) is theoretically studied using the non-interacting Anderson tunneling Hamiltonian method. We show that the asymmetric configuration of QD- scatter system strongly impresses the amplitude and spectrum of quantum wire nanostructure transmission characteristics. It is shown that whenever the balanced number of quantum dots in two rings is substituted by unbalanced scheme, the number of forbidden mini-bands in quantum wire conductance increases and QW-nanostructure electronic conductance contains rich spectral properties due to appearance of the new anti-resonance and resonance points in spectrum. Considering the suitable gap between nano-rings can strengthen the amplitude of new resonant peaks in the QW conductance spectrum. The proposed asymmetric quantum ring scatter system idea in this paper opens a new insight on designing quantum wire nano structure for given electronic conductance.

  19. National Synchrotron Light Source II storage ring vacuum systems

    DOE PAGES

    Hseuh, Hsiao-Chaun; Hetzel, Charles; Leng, Shuwei; ...

    2016-04-05

    The National Synchrotron Light Source II, completed in 2014, is a 3-GeV synchrotron radiation (SR) facility at Brookhaven National Laboratory and has been in steady operation since. With a design electron current of 500 mA and subnanometer radians horizontal emittance, this 792-m circumference storage ring is providing the highest flux and brightness x-ray beam for SR users. Also, the majority of the storage ring vacuum chambers are made of extruded aluminium. Chamber sections are interconnected using low-impedance radiofrequency shielded bellows. SR from the bending magnets is intercepted by water-cooled compact photon absorbers resided in the storage ring chambers. Finally, thismore » paper presents the design of the storage ring vacuum system, the fabrication of vacuum chambers and other hardware, the installation, the commissioning, and the continuing beam conditioning of the vacuum systems.« less

  20. [Application of the elliptic fourier functions to the description of avian egg shape].

    PubMed

    Ávila, Dennis Denis

    2014-12-01

    Egg shape is difficult to quantify due to the lack of an exact formula to describe its geometry. Here I described a simple algorithm to characterize and compare egg shapes using Fourier functions. These functions can delineate any closed contour and had been previously applied to describe several biological objects. I described, step by step, the process of data acquisition, processing and the use of the SHAPE software to extract function coefficients in a study case. I compared egg shapes in three birds' species representing different reproductive strategies: Cuban Parakeet (Aratinga euops), Royal Tern (Thalasseus maximus) and Cuban Blackbird (Dives atroviolaceus). Using 73 digital pictures of eggs kept in Cuban scientific collections, I calculated Fourier descriptors with 4, 6, 8, 16 and 20 harmonics. Descriptors were reduced by a Principal Component Analysis and the scores of the eigen-values that account for 90% of variance were used in a Lineal Discriminant Function to analyze the possibility to differentiate eggs according to its shapes. Using four harmonics, the first five component accounted for 97% of shape variances; more harmonics diluted the variance increasing to eight the number of components needed to explain most of the variation. Convex polygons in the discriminant space showed a clear separation between species, allowing trustful discrimination (classification errors between 7-15%). Misclassifications were related to specific egg shape variability between species. In the study case, A. euops eggs were perfectly classified, but for the other species, errors ranged from 5 to 29% of misclassifications, in relation to the numbers or harmonics and components used. The proposed algorithm, despite its apparent mathematical complexity, showed many advantages to describe eggs shape allowing a deeper understanding of factors related to this variable.

  1. Surgical capacity building in Timor-Leste: a review of the first 15 years of the Royal Australasian College of Surgeons-led Australian Aid programme.

    PubMed

    Guest, Glenn D; Scott, David F; Xavier, Joao P; Martins, Nelson; Vreede, Eric; Chennal, Antony; Moss, Daliah; Watters, David A

    2017-06-01

    Timor-Leste suffered a destructive withdrawal by the Indonesian military in 1999, leaving only 20 Timorese-based doctors and no practising specialists for a population of 700 000 that has now grown to 1.2 million. This article assesses the outcomes and impact of Royal Australasian College of Surgeons (RACS) specialist medical support from 2001 to 2015. Three programmes were designed collaboratively with the Timor-Leste Ministry of Health and Australian Aid. The RACS team began to provide 24/7 resident surgical and anaesthesia services in the capital, Dili, from July 2001. The arrival of the Chinese and Cuban Medical Teams provided a medical workforce, and the Cubans initiated undergraduate medical training for about 1000 nationals both in Cuba and in Timor-Leste, whilst RACS focused on specialist medical training. Australian Aid provided AUD$20 million through three continuous programmes over 15 years. In the first 10 years over 10 000 operations were performed. Initially only 10% of operations were done by trainees but this reached 77% by 2010. Twenty-one nurse anaesthetists were trained in-country, sufficient to cover the needs of each hospital. Seven Timorese doctors gained specialist qualifications (five surgery, one ophthalmology and one anaesthesia) from regional medical schools in Papua New Guinea, Fiji, Indonesia and Malaysia. They introduced local specialist and family medicine diploma programmes for the Cuban graduates. Timor-Leste has developed increasing levels of surgical and anaesthetic self-sufficiency through multi-level collaboration between the Ministry of Health, Universidade Nacional de Timor Lorosa'e, and sustained, consistent support from external donors including Australian Aid, Cuba and RACS. © 2016 Royal Australasian College of Surgeons.

  2. Psychiatric Disorders Differently Correlate with Physical Self-Rated Health across Ethnic Groups.

    PubMed

    Assari, Shervin

    2017-11-13

    In this study, we compared 10 ethnic groups for associations between psychiatric disorders and physical self-rated health (SRH) in the United States. Data came from the Collaborative Psychiatric Epidemiology Surveys (CPES), 2001-2003. The study included 7587 non-Latino White, 4746 African American, 1442 Mexican, 1106 other Hispanic, 656 other Asian, 600 Chinese, 577 Cuban, 520 Vietnamese, 508 Filipino, and 495 Puerto Rican individuals. The Composite International Diagnostic Interview (CIDI) was used to measure psychiatric disorders, including major depressive disorder (MDD), general anxiety disorder (GAD), social phobia, panic disorder, post-traumatic stress disorder (PTSD), alcohol abuse, and binge eating disorders. A single-item measure was used to estimate physical SRH. Demographic (age and gender) and socioeconomic (education and income) factors were also measured. Unadjusted and adjusted correlations between psychiatric disorders and physical SRH were calculated. Major ethnic variations were found in the correlation between psychiatric disorders and physical SRH; as well as the role of demographic and socioeconomic status (SES) factors in explaining these associations. non-Hispanic Whites, Cubans, and African Americans showed more correlations between psychiatric disorders and physical SRH than other ethnic groups. In non-Hispanic Whites, the associations between psychiatric disorders and physical SRH were explained by demographic factors. In African Americans, the link between psychiatric disorders and poor physical SRH were explained by SES indicators. In conclusion , although single-item physical SRH measures are traditionally assumed to reflect the physical health needs of populations, they may also indicate psychiatric disorders in some ethnic groups, such as non-Hispanic Whites, Cubans, and African Americans. Demographic and socioeconomic factors also have differential roles in explaining the link between psychiatric disorders and physical SRH. Physical SRH does not exclusively reflect physical health, and it may be more biased by mental health across some ethnic groups.

  3. Phylodynamics of the HIV-1 epidemic in Cuba.

    PubMed

    Delatorre, Edson; Bello, Gonzalo

    2013-01-01

    Previous studies have shown that the HIV-1 epidemic in Cuba displayed a complex molecular epidemiologic profile with circulation of several subtypes and circulating recombinant forms (CRF); but the evolutionary and population history of those viral variants remains unknown. HIV-1 pol sequences of the most prevalent Cuban lineages (subtypes B, C and G, CRF18_cpx, CRF19_cpx, and CRFs20/23/24_BG) isolated between 1999 and 2011 were analyzed. Maximum-likelihood analyses revealed multiple introductions of subtype B (n≥66), subtype C (n≥10), subtype G (n≥8) and CRF18_cpx (n≥2) viruses in Cuba. The bulk of HIV-1 infections in this country, however, was caused by dissemination of a few founder strains probably introduced from North America/Europe (clades B(CU-I) and B(CU-II)), east Africa (clade C(CU-I)) and central Africa (clades G(CU), CRF18(CU) and CRF19(CU)), or locally generated (clades CRFs20/23/24_BG). Bayesian-coalescent analyses show that the major HIV-1 founder strains were introduced into Cuba during 1985-1995; whereas the CRFs_BG strains emerged in the second half of the 1990s. Most HIV-1 Cuban clades appear to have experienced an initial period of fast exponential spread during the 1990s and early 2000s, followed by a more recent decline in growth rate. The median initial growth rate of HIV-1 Cuban clades ranged from 0.4 year⁻¹ to 1.6 year⁻¹. Thus, the HIV-1 epidemic in Cuba has been a result of the successful introduction of a few viral strains that began to circulate at a rather late time of the AIDS pandemic, but then were rapidly disseminated through local transmission networks.

  4. Cuban Americans have the highest rates of peripheral arterial disease in diverse Hispanic/Latino communities.

    PubMed

    Allison, Matthew A; Gonzalez, Franklyn; Raij, Leopoldo; Kaplan, Robert; Ostfeld, Robert J; Pattany, Maria S; Heiss, Gerardo; Criqui, Michael H

    2015-09-01

    Because Hispanic ethnicity in the United States is heterogeneous, the purpose of this study was to determine the epidemiology of peripheral arterial disease (PAD) within U.S. Hispanic/Latino groups defined by national background. This analysis included 9648 men and women older than 45 years enrolled in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL). The ankle-brachial index (ABI) was computed as the higher of the posterior tibial and dorsalis pedis systolic blood pressures for each leg divided by the higher brachial artery systolic blood pressure. The index ABI was the higher of the two. An ABI ≤0.90 was the criterion for the presence of PAD. The mean age was 56 years, and 55% were female. Overall, the prevalence of an ABI ≤0.90 (PAD), 0.90 to 0.99 (borderline), 1.0 to 1.39 (normal), and ≥1.40 (high) was 5.7%, 19.3%, 72.5%, and 2.6%, respectively. After multivariable adjustment for PAD risk factors and compared with Mexicans, Cubans had a nearly threefold higher odds for PAD (odds ratio, 2.9; 95% confidence interval, 1.9-4.4). The odds of PAD for the other Hispanic/Latino groups ranged from 1.2 to 1.8. Although men had a more than threefold higher odds of an ABI ≥1.40 (3.6; 2.0-6.5), the odds did not differ significantly by Hispanic/Latino background. Compared with Mexican Americans, all other Hispanic/Latino background groups have a significantly higher odds of having PAD, with the odds being nearly threefold higher among Cubans. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  5. A novel presenilin 1 mutation (L174 M) in a large Cuban family with early onset Alzheimer disease.

    PubMed

    Bertoli Avella, A M; Marcheco Teruel, B; Llibre Rodriguez, J J; Gomez Viera, N; Borrajero Martinez, I; Severijnen, E A; Joosse, M; van Duijn, C M; Heredero Baute, L; Heutink, P

    2002-10-01

    We studied a Cuban family with presenile dementia (autosomal dominant) consisting of 281 members within six generations, the proband descended from a Spanish founder. Mean age at onset was 59 years of age. Memory impairment was the main symptom in all patients, additionally, ischemic episodes were described in 4 (n = 18) patients. Neuropathological examination of brain material (1 patient) revealed neuronal loss, amyloid plaques, and neurofibrillary tangles. Thirty DNA samples were genotyped (regions on chromosome 1, 3, 10, 12, 14, 17, 19, 20, and 21). A maximum Lod score of 3.79 at theta = 0 was obtained for marker D14S43, located in a 9-cM interval in which all patients shared the same haplotype. Sequencing of the PSEN1 gene revealed a heterozygous base substitution, C520A (exon 6), which is predicted to cause an amino acid change from leucine to methionine in the TMIII of the presenilin 1 protein. The mutation was found to co-segregate with the disease phenotype and the associated disease haplotype. The C --> A change was not observed in 80 control chromosomes from the Cuban population. Leucine at position 174 is highly conserved among species and is identical in presenilin 1 and presenilin 2 proteins. We propose the L174 M mutation might lead to an abnormal N-terminal and probably C-terminal fragments and malfunction of the protein complex. In conclusion, we found a novel PSEN1 mutation in a large family with clinical and pathological diagnosis of early onset familial Alzheimer disease, which may be relevant for other Hispanic populations.

  6. Genetic evidence of hybridization between the critically endangered Cuban crocodile and the American crocodile: implications for population history and in situ/ex situ conservation

    PubMed Central

    Milián-García, Y; Ramos-Targarona, R; Pérez-Fleitas, E; Sosa-Rodríguez, G; Guerra-Manchena, L; Alonso-Tabet, M; Espinosa-López, G; Russello, M A

    2015-01-01

    Inter-specific hybridization may be especially detrimental when one species is extremely rare and the other is abundant owing to the potential for genetic swamping. The Cuban crocodile (Crocodylus rhombifer) is a critically endangered island endemic largely restricted to Zapata Swamp, where it is sympatric with the widespread American crocodile (C. acutus). An on-island, C. rhombifer captive breeding program is underway with the goals of maintaining taxonomic integrity and providing a source of individuals for reintroduction, but its conservation value is limited by lack of genetic information. Here we collected mtDNA haplotypic and nuclear genotypic data from wild and captive C. rhombifer and C. acutus in Cuba to: (1) investigate the degree of inter-specific hybridization in natural (in situ) and captive (ex situ) populations; (2) quantify the extent, distribution and in situ representation of genetic variation ex situ; and (3) reconstruct founder relatedness to inform management. We found high levels of hybridization in the wild (49.1%) and captivity (16.1%), and additional evidence for a cryptic lineage of C. acutus in the Antilles. We detected marginally higher observed heterozygosity and allelic diversity ex situ relative to the wild population, with captive C. rhombifer exhibiting over twice the frequency of private alleles. Although mean relatedness was high in captivity, we identified 37 genetically important individuals that possessed individual mean kinship (MK) values lower than the population MK. Overall, these results will guide long-term conservation management of Cuban crocodiles for maintaining the genetic integrity and viability of this species of high global conservation value. PMID:25335559

  7. Lessons from Cuba for Global Precision Medicine: CYP2D6 Genotype Is Not a Robust Predictor of CYP2D6 Ultrarapid Metabolism.

    PubMed

    Dorado, Pedro; González, Idilio; Naranjo, María Eugenia G; de Andrés, Fernando; Peñas-Lledó, Eva María; Calzadilla, Luis Ramón; LLerena, Adrián

    2017-01-01

    A long-standing question and dilemma in precision medicine is whether and to what extent genotyping or phenotyping drug metabolizing enzymes such as CYP2D6 can be used in real-life global clinical and societal settings. Although in an ideal world using both genotype and phenotype biomarkers are desirable, this is not always feasible for economic and practical reasons. Moreover, an additional barrier for clinical implementation of precision medicine is the lack of correlation between genotype and phenotype, considering that most of the current methods include only genotyping. Thus, the present study evaluated, using dextromethorphan as a phenotyping probe, the relationship between CYP2D6 phenotype and CYP2D6 genotype, especially for the ultrarapid metabolizer (UM) phenotype. We report in this study, to the best of our knowledge, the first comparative clinical pharmacogenomics study in a Cuban population sample (N = 174 healthy volunteers) and show that the CYP2D6 genotype is not a robust predictor of the CYP2D6 ultrarapid metabolizer (mUM) status in Cubans. Importantly, the ultrarapid CYP2D6 phenotype can result in a host of health outcomes, such as drug resistance associated with subtherapeutic drug concentrations, overexposure to active drug metabolites, and altered sensitivity to certain human diseases by virtue of altered metabolism of endogenous substrates of CYP2D6. Hence, phenotyping tests for CYP2D6 UMs appear to be a particular necessity for precision medicine in the Cuban population. Finally, in consideration of ethical and inclusive representation in global science, we recommend further precision medicine biomarker research and funding in support of neglected or understudied populations worldwide.

  8. Quantum mechanical design of efficient second-order nonlinear optical materials based on heteroaromatic imido-substituted hexamolybdates: first theoretical framework of POM-based heterocyclic aromatic rings.

    PubMed

    Janjua, Muhammad Ramzan Saeed Ashraf

    2012-11-05

    This work was inspired by a previous report (Janjua et al. J. Phys. Chem. A 2009, 113, 3576-3587) in which the nonlinear-optical (NLO) response strikingly improved with an increase in the conjugation path of the ligand and the nature of hexamolybdates (polyoxometalates, POMs) was changed into a donor by altering the direction of charge transfer with a second aromatic ring. Herein, the first theoretical framework of POM-based heteroaromatic rings is found to be another class of excellent NLO materials having double heteroaromatic rings. First hyperpolarizabilities of a large number of push-pull-substituted conjugated systems with heteroaromatic rings have been calculated. The β components were computed at the density functional theory (DFT) level (BP86 geometry optimizations and LB94 time-dependent DFT). The largest β values are obtained with a donor (hexamolybdates) on the benzene ring and an acceptor (-NO(2)) on pyrrole, thiophene, and furan rings. The pyrrole imido-substituted hexamolybdate (system 1c) has a considerably large first hyperpolarizability, 339.00 × 10(-30) esu, and it is larger than that of (arylimido)hexamolybdate, calculated as 0.302 × 10(-30) esu (reference system 1), because of the double aromatic rings in the heteroaromatic imido-substituted hexamolybdates. The heteroaromatic rings act as a conjugation bridge between the electron acceptor (-NO(2)) and donor (polyanion). The introduction of an electron donor into heteroaromatic rings significantly enhances the first hyperpolarizabilities because the electron-donating ability is substantially enhanced when the electron donor is attached to the heterocyclic aromatic rings. Interposing five-membered auxiliary fragments between strong donor (polyanion) or acceptor (-NO(2)) groups results in a large computed second-order NLO response. The present investigation provides important insight into the NLO properties of (heteroaromatic) imido-substituted hexamolybdate derivatives because these compounds exhibit enhanced hyperpolarizabilities compared to typical NLO arylimido hexamolybdates and heterocyclic aromatic rings reported in the literature.

  9. ACCELERATORS: RF system design and measurement of HIRF-CSRe

    NASA Astrophysics Data System (ADS)

    Xu, Zhe; Zhao, Hong-Wei; Wang, Chun-Xiao; Xia, Jia-Wen; Zhan, Wen-Long; Bian, Zhi-Bin

    2009-05-01

    An RF system for the CSRe (cooling storage experimental ring) is designed and manufactured domestically. The present paper mainly describes the RF system design in five main sections: ferrite ring, RF cavity, RF generator, low level system and cavity cooling. The cavity is based on a type of coaxial resonator which is shorted at the end with one gap and loaded with domestic ferrite rings. The RF generator is designed in the push-pull mode and the low level control system is based on a DSP+FGPA+DDS+USB interface and has three feedback loops. Finally we give the results of the measurement on our system.

  10. Use of Silica-Encapsulated Pseudomonas sp. Strain NCIB 9816-4 in Biodegradation of Novel Hydrocarbon Ring Structures Found in Hydraulic Fracturing Waters

    PubMed Central

    Aukema, Kelly G.; Kasinkas, Lisa; Aksan, Alptekin

    2014-01-01

    The most problematic hydrocarbons in hydraulic fracturing (fracking) wastewaters consist of fused, isolated, bridged, and spiro ring systems, and ring systems have been poorly studied with respect to biodegradation, prompting the testing here of six major ring structural subclasses using a well-characterized bacterium and a silica encapsulation system previously shown to enhance biodegradation. The direct biological oxygenation of spiro ring compounds was demonstrated here. These and other hydrocarbon ring compounds have previously been shown to be present in flow-back waters and waters produced from hydraulic fracturing operations. Pseudomonas sp. strain NCIB 9816-4, containing naphthalene dioxygenase, was selected for its broad substrate specificity, and it was demonstrated here to oxidize fundamental ring structures that are common in shale-derived waters but not previously investigated with this or related enzymes. Pseudomonas sp. NCIB 9816-4 was tested here in the presence of a silica encasement, a protocol that has previously been shown to protect bacteria against the extremes of salinity present in fracking wastewaters. These studies demonstrate the degradation of highly hydrophobic compounds by a silica-encapsulated model bacterium, demonstrate what it may not degrade, and contribute to knowledge of the full range of hydrocarbon ring compounds that can be oxidized using Pseudomonas sp. NCIB 9816-4. PMID:24907321

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

    NASA Astrophysics Data System (ADS)

    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.

  12. Non-Linear Dynamics of Saturn’s Rings

    NASA Astrophysics Data System (ADS)

    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 of the rings and can renew rings by shielding and recycling the material within them, depending on how long the mass is sequestered. We can ask: Are Saturn’s rings a chaotic non-linear driven system?

  13. The Cuban “Exception”: The Development of an Advanced Scientific System in an Underdeveloped Country

    NASA Astrophysics Data System (ADS)

    Baracca, Angelo

    Science, education, politics, social development and economics are today considered to be highly interdependent. Although none of these factors can exist on their own, they have nevertheless often been considered in isolation from one other, or studies of their interactions have been confined to the consideration of more or less local contexts. When it comes to studying the history of physics in Cuba, however, it is not only inconceivable to separate scientific developments from their social, political, and cultural contexts. But, as this volume shows, the history of physics in Cuba cannot just focus on local contexts since it is closely entangled with global history, from colonialism to the Cold War.

  14. Support System for Solar Receivers

    NASA Technical Reports Server (NTRS)

    Kiceniuk, T.

    1985-01-01

    Hinged split-ring mounts insure safe support of heavy receivers. In addition to safer operation and damage-free mounting system provides more accurate focusing, and small incremental adjustments of ring more easily made.

  15. Novel stereocontrolled approach to syn- and anti-oxepene-cyclogeranyl trans-fused polycyclic systems: asymmetric total synthesis of (-)-Aplysistatin, (+)-Palisadin A, (+)-Palisadin B, (+)-12-hydroxy-palisadin B, and the AB ring system of adociasulfate-2 and toxicol A.

    PubMed

    Couladouros, Elias A; Vidali, Veroniki P

    2004-08-06

    A new stereocontrolled method for the formation of trans-anti cyclogeranyl-oxepene systems is described. The demanding stereochemistry is secured by stereoselective coupling of a cyclogeranyl tertiary alcohol with a 1,2-unsymmetrically substituted epoxide, while the formation of the highly strained oxepene is achieved employing ring-closing metathesis. Since the stereochemistry of the trans-fused 6,7-ring system is determined by the epoxide, the method also allows the construction of trans-syn 6,7-ring systems. This approach leads to the synthesis of the AB fragment of Adociasulfate-2 and Toxicol A, for the first time. The flexibility and efficiency of the presented strategy is demonstrated by the total asymmetric synthesis of (-)-Aplysistatin, (+)-Palisadin A, (+)-12-hydroxy-Palisadin B, and (+)-Palisadin B, employing two similar key intermediates.

  16. Analysis of a Triple Star System Occulted By Saturn’s Rings

    NASA Astrophysics Data System (ADS)

    Bratcher, Allison; Colwell, J. E.; Bolin, B.

    2012-10-01

    On January 4, 2012, the Ultraviolet Imaging Spectrograph aboard the Cassini Spacecraft observed Saturn’s rings as they occulted the triple star system, Iota Orionis. Remarkably, the brightest star was occulted by the moon Prometheus, and we provide the timing information of first and last contact for navigation purposes and a chord across the moon. The large separation of the individual stars projected in the ring plane makes it possible to measure the profiles of narrow features in the rings as they were occulted by each of the three stars. This occultation thus provides a unique opportunity to measure short-scale longitudinal variations in narrow ringlets with stellar occultation data that usually provide only a single longitudinal sample. Iota Orionis has a low elevation angle (B=1.4 degrees) above the plane of the rings, enhancing the sensitivity of the occultation (by a factor of 1/sin(B)=41) to the optically thin regions of the rings such as the C Ring and the Cassini Division as well as faint ringlets in the Encke gap. We distinguished the three signals by creating a model triple star signal using data from another occultation. We were able to identify several faint, narrow ringlets, including two in the Encke gap, occulted by two of the three stars and more prominent ringlets, such as the Huygens ringlet, in all three stellar light curves. We present the equivalent widths of these ringlets in the data from this triple star system and limits on ring variability over the azimuthal separation of the stars that ranges from 6000 km at the inner C ring to 200 km at the outer A ring.

  17. 31 CFR 515.204 - Importation of and dealings in certain merchandise.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Is of Cuban origin; or (2) Is or has been located in or transported from or through Cuba; or (3) Is made or derived in whole or in part of any article which is the growth, produce or manufacture of Cuba...

  18. Castro’s Cuba: Quo Vadis

    DTIC Science & Technology

    2006-12-01

    music, films, theater productions and cuisine ; performances by Cuban ballet dance troupes, musicians, and salsa bands in global venues; touring...by French authorities in 1994 in Sudan and is now serving a life sentence in France. See Aleksander Boyd, “An Overview on the Dynamics of Hugo

  19. Spanish Aid in Clinical Dietetics.

    ERIC Educational Resources Information Center

    Bringas, Juliet G.; Chan, Teresa Y.

    Designed to aid dietitians, nutritionists, and other health professionals to better serve the nutritional needs of Hispanics, this bilingual booklet describes the different cultural eating habits of Mexican, Cuban, and Puerto Rican Americans, with in-depth description of Mexican Americans. Written in Spanish and English, the booklet includes…

  20. 14 CFR 152.403 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... East, Southeast Asia, the Indian subcontinent, or the Pacific Islands, including, but not limited to China, Japan, Korea, the Philippine Islands, and Samoa; or (4) American Indian or Alaskan Native: A... Mexican, Puerto Rican, Cuban, Central or South American or other Spanish culture or origin, regardless of...

  1. Differences in private health insurance coverage for working male Hispanics.

    PubMed

    Fronstin, P; Goldberg, L G; Robins, P K

    1997-01-01

    In 1993, 33.8% of all nonelderly adult Hispanics living in the United States lacked health insurance coverage (either private or public), compared to 8.1% of the entire nonelderly population. Because Hispanics are more likely to be uninsured than any other ethnic group and because they are the fastest growing minority group in the United States, the increase in the Hispanic population is likely to increase the proportion of the population without health insurance. Particularly striking are differences in private health insurance coverage among the three major Hispanic groups--Cuban-Americans, Mexican-Americans, and Puerto Ricans. In this paper, regression-based decomposition analysis is used to explain the sources of differences in private health insurance coverage among working males in these three group. The results indicate that among the study population, Cuban-Americans have higher rates of private health insurance coverage than Mexican-Americans and Puerto Ricans, and that wage rates, levels of education, age, occupation, and marital status explain most of the difference.

  2. The Mn4Ca-cluster of the photosynthetic oxygen evolving centre: its structure, function and evolution.

    PubMed

    Barber, James

    2016-10-05

    Photosystem II is the chlorophyll containing enzyme in which the very first chemical energy storing reaction of photosynthesis occurs. It does so by splitting water into molecular oxygen and hydrogen equivalents at a catalytic centre composed of four Mn ions and one Ca2+. All the oxygen in the atmosphere is derived from this reaction and without it the biosphere, as we know it, would not exist. Indeed its appearance about 3 billion years ago gave rise to the "big bang of evolution". Thus understanding the structure and functioning of this metal cluster is a major topic in science and here I discuss it in terms of research over of the last twelve years dating back to when it was first proposed to be a Mn3CaO4 cubane with the fourth Mn attached to cubane by one of its oxo bridging bonds. In so doing a number of novel properties emerge for this metallo-protein with implications for its mechanism and evolutionary origin.

  3. Regioselectivity of H Cluster Oxidation

    PubMed Central

    2011-01-01

    The H2-evolving potential of [FeFe] hydrogenases is severely limited by the oxygen sensitivity of this class of enzymes. Recent experimental studies on hydrogenase from C. reinhardtii point to O2-induced structural changes in the [Fe4S4] subsite of the H cluster. Here, we investigate the mechanistic basis of this observation by means of density functional theory. Unexpectedly, we find that the isolated H cluster shows a pathological catalytic activity for the formation of reactive oxygen species such as O2– and HO2–. After protonation of O2–, an OOH radical may coordinate to the Fe atoms of the cubane, whereas H2O2 specifically reacts with the S atoms of the cubane-coordinating cysteine residues. Both pathways are accompanied by significant structural distortions that compromise cluster integrity and thus catalytic activity. These results explain the experimental observation that O2-induced inhibition is accompanied by distortions of the [Fe4S4] moiety and account for the irreversibility of this process. PMID:22106822

  4. [Nutritional status of Cuban elders in three different geriatric scenarios: community, geriatrics service, nursery home].

    PubMed

    González Hernández, Alina; Cuyá Lantigua, Magdalena; González Escudero, Hilda; Sánchez Gutiérrez, Ramón; Cortina Martínez, Rafael; Barreto Penié, Jesús; Santana Porbén, Sergio; Rojas Pérez, Alberto

    2007-09-01

    The undernutrition rates observed in Cuban elders surveyed in three different geriatric scenarios: Community: coastal town of Cojímar (City of Havana); Geriatrics Service ("Hermanos Ameijeiras" Hospital, City of Havana); and Nursery Home (city of Cárdenas, province of Matanzas) by means of the Mini Nutritional Assessment (MNA) of the Elderly are presented. Undernutrition rates were 2.7% among elders surveyed in the coastal community of Cojímar, but increased to become 91.6% among those admitted to the hospital Geriatrics Service, and 95.3% for those institutionalized in the Nursery Home, respectively. The occurrence of undernutrition can be low among elders living freely in the community, but it might affect a vast number of those seeking medical assistance at the public health institutions. Extent of undernutrition among elders in geriatric assistance scenarios should lead to the adoption of the required measures for early identification, and timely treatment, of this health problem.

  5. Cuban epidemic neuropathy, 1991 to 1994: history repeats itself a century after the "amblyopia of the blockade".

    PubMed Central

    Ordúñez-García, P O; Nieto, F J; Espinosa-Brito, A D; Caballero, B

    1996-01-01

    The 1991 to 1994 epidemic of neuropathy in Cuba has been one of the more devastating in recent history, affecting more than 50,000 people throughout the entire country with clinical manifestations of optic and peripheral neuropathy. Although the causes are not entirely clear, it seems that a combination of acute nutritional deficiency and the toxic effects of tobacco and possibly other unidentified toxic substances is involved. The epidemic coincided with the acute worsening of the economic situation on the island following political changes in Eastern European countries and a tightening of the US economic embargo. This paper reviews reports of a strikingly similar epidemic known as the "Amblyopia of the Blockade," which occurred in Cuba almost a century ago when the island was undergoing a US naval blockade during the Cuban-Spanish-American war. It discusses the parallelism with the recent epidemic as well as the implications of this historical evidence to clarify further the ultimate causes of these epidemics. PMID:8629731

  6. Multiple internal seal right micro-electro-mechanical system vacuum package

    NASA Technical Reports Server (NTRS)

    Shcheglov, Kirill V. (Inventor); Wiberg, Dean V. (Inventor); Hayworth, Ken J. (Inventor); Yee, Karl Y. (Inventor); Bae, Youngsam (Inventor); Challoner, A. Dorian (Inventor); Peay, Chris S. (Inventor)

    2007-01-01

    A Multiple Internal Seal Ring (MISR) Micro-Electro-Mechanical System (MEMS) vacuum package that hermetically seals MEMS devices using MISR. The method bonds a capping plate having metal seal rings to a base plate having metal seal rings by wafer bonding the capping plate wafer to the base plate wafer. Bulk electrodes may be used to provide conductive paths between the seal rings on the base plate and the capping plate. All seals are made using only metal-to-metal seal rings deposited on the polished surfaces of the base plate and capping plate wafers. However, multiple electrical feed-through metal traces are provided by fabricating via holes through the capping plate for electrical connection from the outside of the package through the via-holes to the inside of the package. Each metal seal ring serves the dual purposes of hermetic sealing and providing the electrical feed-through metal trace.

  7. Cassini Radio Occultations of Saturn's Rings: Scattered Signal and Particle Sizes

    NASA Astrophysics Data System (ADS)

    Thomson, F.; Wong, K.; Marouf, E.; French, R.; Rappaport, N.; McGhee, C.; Anabtawi, A.; Asmar, S.; Barbinis, E.; Fleischman, D.; Goltz, G.; Johnston, D.; Rochblatt, D.

    2005-08-01

    Eight Cassini radio occultations of Saturn's rings were conducted from May 3 to September 5, 2005. During any given occultation, Cassini transmits Ka-, X-, and S-band sinusoidal signals (0.94, 3.6, and 13 cm-wavelength) through the rings. Spectral analysis of the perturbed signals received at stations of the Deep Space Network (DSN) reveals two distinct signal components. The first is the direct signal, a narrowband component representing the incident sinusoid emerging from the rings reduced in amplitude and changed in phase. The second is the scattered signal, a broadband component, representing near-forward scattering by ring particles. After reconstruction to remove diffraction effects, time history of the direct signal yields profiles of ring structure at resolution approaching ˜50 m. Of primary concern here is the broadband component. For the first time ever, clearly detectable scattered signals were observed at all three (Ka/X/S) bands. A single X/S radio occultation by Voyager 1 in 1980 detected scattered signal at X-band only, primarily because of the small ring opening angle B=5.9o at the time, compared with 19.1 ≤ B ≤ 23.6o for Cassini. Time histories of the observed spectra (spectrograms) and their dependence on wavelength provide important information about physical ring properties, including abundance of meter-size particles, particle crowding, clustering, spatial anisotropy, vertical ring profile and thickness. Cassini occultation orbits were optimized to map scattering by individual ring features into nearly non-overlapping spectral bands, allowing unambiguous identification of the contribution of ring features to the computed spectrograms. We present Ka/X/S spectrograms over the full extent of the ring system and relate their behavior to observed ring structure. The spectrograms imply presence of meters-size particles throughout the ring system. Preliminary results regarding the particle size distribution and vertical ring profile of selected ring features are presented. Contributions of personnel of the DSN are gratefully acknowledged.

  8. Jupiter's Ring Halo

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (km) per picture element (pixel) along the rings; however, because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow peering back toward the Sun; the ring was approximately 2,300,000 kilometers (km) away. The arc on the far right of the image is produced by sunlight scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age.

    Jupiter's ring system is composed of three parts -- a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, which lies exterior to the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the far left side of the figure. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow.

    A faint mist of particles can be seen above and below the main rings; this vertically extended, toroidal 'halo' is unusual in planetary rings, and is probably caused by electromagnetic forces which can push small grains out of the ring plane. Halo material is present across this entire image, implying that it reaches more than 27,000 km above the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic. In order to accentuate faint features in the image, different brightnesses are shown through color, with the brightest being white or yellow and the faintest purple.

    The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at: http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at: http:/ /www.jpl.nasa.gov/galileo/sepo.

  9. Capture, acceleration and bunching rf systems for the MEIC booster and storage rings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Shaoheng; Guo, Jiquan; Lin, Fanglei

    2015-09-01

    The Medium-energy Electron Ion Collider (MEIC), proposed by Jefferson Lab, consists of a series of accelerators. The electron collider ring accepts electrons from CEBAF at energies from 3 to 12 GeV. Protons and ions are delivered to a booster and captured in a long bunch before being ramped and transferred to the ion collider ring. The ion collider ring accelerates a small number of long ion bunches to colliding energy before they are re-bunched into a high frequency train of very short bunches for colliding. Two sets of low frequency RF systems are needed for the long ion bunch energymore » ramping in the booster and ion collider ring. Another two sets of high frequency RF cavities are needed for re-bunching in the ion collider ring and compensating synchrotron radiation energy loss in the electron collider ring. The requirements from energy ramping, ion beam bunching, electron beam energy compensation, collective effects, beam loading and feedback capability, RF power capability, etc. are presented. The preliminary designs of these RF systems are presented. Concepts for the baseline cavity and RF station configurations are described, as well as some options that may allow more flexible injection and acceleration schemes.« less

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

    NASA Astrophysics Data System (ADS)

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

    2016-05-01

    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.

  11. How Jupiter's Ring Was Discovered.

    ERIC Educational Resources Information Center

    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)

  12. Toward Detection of Exoplanetary Rings via Transit Photometry: Methodology and a Possible Candidate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aizawa, Masataka; Masuda, Kento; Suto, Yasushi

    The detection of a planetary ring of exoplanets remains one of the most attractive, but challenging, goals in the field of exoplanetary science. We present a methodology that implements a systematic search for exoplanetary rings via transit photometry of long-period planets. This methodology relies on a precise integration scheme that we develop to compute a transit light curve of a ringed planet. We apply the methodology to 89 long-period planet candidates from the Kepler data so as to estimate, and/or set upper limits on, the parameters of possible rings. While the majority of our samples do not have sufficient signal-to-noise ratios (S/Ns) to place meaningfulmore » constraints on ring parameters, we find that six systems with higher S/Ns are inconsistent with the presence of a ring larger than 1.5 times the planetary radius, assuming a grazing orbit and a tilted ring. Furthermore, we identify five preliminary candidate systems whose light curves exhibit ring-like features. After removing four false positives due to the contamination from nearby stars, we identify KIC 10403228 as a reasonable candidate for a ringed planet. A systematic parameter fit of its light curve with a ringed planet model indicates two possible solutions corresponding to a Saturn-like planet with a tilted ring. There also remain two other possible scenarios accounting for the data; a circumstellar disk and a hierarchical triple. Due to large uncertain factors, we cannot choose one specific model among the three.« less

  13. Gaseous toroid around Saturn. [Saturnian ring system for atomic hydrogen trapping in Titan atmospheric model

    NASA Technical Reports Server (NTRS)

    Mcdonough, T. R.

    1974-01-01

    The trapping of Titan's escaping atmosphere in the Saturnian system by a toroidal ring is discussed. The radius of the toroid is comparable to Titan's orbit, or about ten times larger than the visible rings. Theoretical atmospheric models are formulated that consider Saturn's gravitational attraction and magnetospheric properties in forming this toroid and in protecting toroid particles from direct ionization by solar wind particles.

  14. Jupiter's Main Ring

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (km) per picture element (pixel) along the rings; however, because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow peering back toward the Sun; the ring was approximately 2,300,000 kilometers (km) away. The arc on the far right of the image is produced by sunlight scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age.

    Jupiter's ring system is composed of three parts -- a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, which lies exterior to the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the far left side of the figure. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow. Some radial structure is barely visible across the ring's ansa. A faint mist of particles can be seen above and below the main rings; this vertically extended 'halo' is unusual in planetary rings, and is probably caused by electromagnetic forces pushing the smallest grains out of the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic.

    Jupiter's main ring is a thin strand of material encircling the planet. The diffuse innermost boundary begins at approximately 123,000 km. The main ring's outer radius is found to be at 128,940 +/-50 km, slightly less than the Voyager value of 129,130 +/-100 km, but very close to the orbit of the satellite Adrastea (128,980 km). The main ring exhibits a marked drop in brightness at 127,849 +/-50 km, lying almost atop the orbit of the Jovian moon Metis at 127,978 km. Satellites seem to affect the structure of even tenuous rings like that found at Jupiter.

    The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at: http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at: http:/ /www.jpl.nasa.gov/galileo/sepo.

  15. The two nerve rings of the hypostomal nervous system of Hydra vulgaris-an immunohistochemical analysis.

    PubMed

    Hufnagel, L A; Kass-Simon, G

    2016-11-01

    In Hydra vulgaris, physiological and pharmacological evidence exists for a hypostomal circumferential neuro-effector pathway that initiates ectodermal pacemaker activity at tentacular-hypostomal loci coordinating body and tentacle contractions. Here, we describe an ectodermal nerve ring that runs below and between the tentacles, and an anti-GABA B receptor antibody-labeled ring coincident with it. The location of this ring is consistent with the physiology of the hypostomal pacemaker systems of hydra. We also describe a distally located, ectodermal ring of nerve fibers that is not associated with anti-GABA B receptor antibody labeling. The neurites and cell bodies of sensory cells contribute to both rings. The location of the distal ring and its sensory cell neurites suggests an involvement in the behavior of the mouth. Between the two rings is a network of anastomosing sensory and ganglion cell bodies and their neurites. Phase contrast, darkfield, and antibody-labeled images reveal that the mouth of hydra comprises five or six epithelial folds whose endoderm extensively labels with anti-GABA B receptor antibody, suggesting that endodermal metabotrobic GABA receptors are also involved in regulating mouth behavior.

  16. In vitro contraction of cytokinetic ring depends on myosin II but not on actin dynamics.

    PubMed

    Mishra, Mithilesh; Kashiwazaki, Jun; Takagi, Tomoko; Srinivasan, Ramanujam; Huang, Yinyi; Balasubramanian, Mohan K; Mabuchi, Issei

    2013-07-01

    Cytokinesis in many eukaryotes involves the contraction of an actomyosin-based contractile ring. However, the detailed mechanism of contractile ring contraction is not fully understood. Here, we establish an experimental system to study contraction of the ring to completion in vitro. We show that the contractile ring of permeabilized fission yeast cells undergoes rapid contraction in an ATP- and myosin-II-dependent manner in the absence of other cytoplasmic constituents. Surprisingly, neither actin polymerization nor its disassembly is required for contraction of the contractile ring, although addition of exogenous actin-crosslinking proteins blocks ring contraction. Using contractile rings generated from fission yeast cytokinesis mutants, we show that not all proteins required for assembly of the ring are required for its contraction in vitro. Our work provides the beginnings of the definition of a minimal contraction-competent cytokinetic ring apparatus.

  17. Reflecting on Culture. (Reflexionando Sobre la Cultura.)

    ERIC Educational Resources Information Center

    Irizarry, Estelle

    1980-01-01

    The article comments on two articles, previously published in the same journal, which address the relationship between the "little" cultural tradition of Chicanos, Cubans, and Puerto Ricans and the "great" tradition of Hispanic arts and letters. Notes similarities among these groups and calls for the banding together of…

  18. Reflections on Educational Reform in Cuba.

    ERIC Educational Resources Information Center

    Lindahl, Ronald A.

    1998-01-01

    Reviews Cuban educational reforms, highlighting 1959, 1976, and 1980s initiatives. Compares Cuba's progress with John Kotter's eight-step process based on establishing a sense of urgency, creating a guiding coalition, developing and communicating the change vision, empowering broad-based action, generating short-term wins, consolidating gains, and…

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

    PubMed Central

    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

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

    PubMed

    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-)).

  1. Saturn's Rings and Associated Ring Plasma Cavity: Evidence for Slow Ring Erosion

    NASA Technical Reports Server (NTRS)

    Farrell, W. M.; Kurth, W. S.; Gurnett, D. A.; Persoon, A. M.; MacDowall, R. J.

    2017-01-01

    We re-examine the radio and plasma wave observations obtained during the Cassini Saturn orbit insertion period, as the spacecraft flew over the northern ring surface into a radial distance of 1.3 Rs (over the C-ring). Voyager era studies suggest the rings are a source of micro-meteoroid generated plasma and dust, with theorized peak impact-created plasma outflows over the densest portion of the rings (central B-ring). In sharp contrast, the Cassini Radio and Plasma Wave System (RPWS) observations identify the presence of a ring-plasma cavity located in the central portion of the B-ring, with little evidence of impact-related plasma. While previous Voyager era studies have predicted unstable ion orbits over the C- ring, leading to field-aligned plasma transport to Saturns ionosphere, the Cassini RPWS observations do not reveal evidence for such instability-created plasma fountains. Given the passive ring loss processes observed by Cassini, we find that the ring lifetimes should extend >10(exp 9) years, and that there is limited evidence for prompt destruction (loss in <100 Myrs).

  2. Saturn's rings and associated ring plasma cavity: Evidence for slow ring erosion

    NASA Astrophysics Data System (ADS)

    Farrell, W. M.; Kurth, W. S.; Gurnett, D. A.; Persoon, A. M.; MacDowall, R. J.

    2017-08-01

    We re-examine the radio and plasma wave observations obtained during the Cassini Saturn orbit insertion period, as the spacecraft flew over the northern ring surface into a radial distance of 1.3 Rs (over the C-ring). Voyager era studies suggest the rings are a source of micro-meteoroid generated plasma and dust, with theorized peak impact-created plasma outflows over the densest portion of the rings (central B-ring). In sharp contrast, the Cassini Radio and Plasma Wave System (RPWS) observations identify the presence of a ring-plasma cavity located in the central portion of the B-ring, with little evidence of impact-related plasma. While previous Voyager era studies have predicted unstable ion orbits over the C-ring, leading to field-aligned plasma transport to Saturn's ionosphere, the Cassini RPWS observations do not reveal evidence for such instability-created plasma 'fountains'. Given the passive ring loss processes observed by Cassini, we find that the ring lifetimes should extend >109 years, and that there is limited evidence for prompt destruction (loss in <100 Myrs).

  3. Glove port retrofit assembly and method of replacing components

    DOEpatents

    Giesen, Isaac M; Cournoyer, Michael E; Rael, David G

    2014-11-18

    What is disclosed is a system for retrofitting a sealed enclosure for performing work therein having an outer enclosure assembly configured to be clamped to the outer annular face of a port ring and form a sealed engagement with the outer annular surface of the port ring, a change assembly having an inner ring and an access element wherein the inner ring has a first annular cylinder body that is sized to be slidably received by the port ring and the access element is configured to be sealably and slidably positioned within the first annular cylinder body of the inner ring.

  4. Thermoelectric effect in Aharonov-Bohm structures.

    PubMed

    Lu, Xin; Wang, Jian-Sheng; Morrel, William G; Ni, Xiaoxi; Wu, Chang-Qin; Li, Baowen

    2015-01-28

    The thermoelectric effects of a single Aharonov-Bohm (SAB) ring and coupled double Aharonov-Bohm (DAB) rings have been investigated on a theoretical basis, taking into account the contributions of both electrons and phonons to the transport process by using the nonequilibrium Green's function technique. The thermoelectric figure of merit of the coupled DAB rings cannot be predicted directly by combining the values of two SAB ring systems due to the contribution of electron-phonon interaction to coupling between the two sites connecting the rings. We find that thermoelectric efficiency can be optimized by modulating the phases of the magnetic flux threading the two rings.

  5. ARC-1986-A86-7032

    NASA Image and Video Library

    1986-01-24

    P-29516 BW Range: 125, 000 kilometers (78,000 miles) Voyager 2's wide-angle camera captured this view of the outer part of the Uranian ring system just 11 minutes before passing though the ring plane. The resolution in this clear-filter view is slightly better than 9 km (6 mi). The brightest, outermost ring is known as epsilon. Interior to epsilon lie (from top) the newly discovered 10th ring of Uranus--designated 1986UR1 and barely visible here--and then the delta, gamma and eta rings.

  6. Toroidal Geometry Stabilizing a Latitudinal Ring of Point Vortices on a Torus

    NASA Astrophysics Data System (ADS)

    Sakajo, Takashi; Shimizu, Yuuki

    2018-06-01

    We carry out the linear stability analysis of a polygonal ring configuration of N point vortices, called an N-ring, along the line of latitude θ _0 on a torus with the aspect ratio α . Deriving a criterion for the stability depending on the parameters N, θ _0 and α , we reveal how the aspect ratio α contributes to the stability of the N-ring. While the N-ring necessarily becomes unstable when N is sufficiently large for fixed α , the stability is closely associated with the geometric property of the torus for variable α ; for low aspect ratio α ˜ 1, N=7 is a critical number determining the stability of the N-ring when it is located along a certain range of latitudes, which is an analogous result to those in a plane and on a sphere. On the other hand, the stability is determined by the sign of curvature for high aspect ratio α ≫ 1. That is to say, the N-ring is neutrally stable if it is located on the inner side of the toroidal surface with a negative curvature, while the N-ring on its outer side with a positive curvature is unstable. Furthermore, based on the linear stability analysis, we describe nonlinear evolution of the N-ring when it becomes unstable. It is difficult to deal with this problem, since the evolution equation of the N point vortices is formulated as a Hamiltonian system with N degrees of freedom, which is in general non-integrable. Thus, we reduce the Hamiltonian system to a simple integrable system by introducing a cyclic symmetry. Owing to this reduction, we successfully find some periodic orbits in the reduced system, whose local bifurcations and global transitions for variable α are characterized in terms of the fundamental group of the torus.

  7. Cycloalkyl-AminoMethylRhodamines: pH Dependent Photophysical Properties Tuned by Cycloalkane Ring Size

    PubMed Central

    Liu, Chuangjun; Best, Quinn A.; Suarez, Brian; Pertile, Jack; McCarroll, Matthew E.; Scott, Colleen N.

    2015-01-01

    A series of fluorescent pH probes based on the spiro-cyclic rhodamine core, aminomethylrhodamines (AMR), was synthesized and the effect of cycloalkane ring size on the acid/base properties of the AMR system was explored. The study involved a series of rhodamine 6G (cAMR6G) and rhodamine B (cAMR) pH probes with cycloalkane ring sizes from C-3 to C-6 on the spiro-cyclic amino group. It is known that the pKa value of cycloalkylamines can be tuned by the different ring sizes in accordance with the Baeyer ring strain theory. Smaller ring amines have lower pKa value, i.e. they're less basic, such that the relative order in cycloalkylamine basicity is: cyclohexyl>cyclopentyl>cyclobutyl>cyclopropyl. Herein, it was found that the pKa values of the cAMR and cAMR6G systems can also be predicted by Baeyer ring strain theory. The pKa values for the cAMR6G series were shown to be higher than the cAMR series by a value of approximately 1. PMID:25686771

  8. Encounter with Saturn: Voyager 1 imaging science results

    USGS Publications Warehouse

    Smith, B.A.; Soderblom, L.; Beebe, R.; Boyce, J.; Briggs, G.; Bunker, A.; Collins, S.A.; Hansen, C.J.; Johnson, T.V.; Mitchell, J.L.; Terrile, R.J.; Carr, M.; Cook, A.F.; Cuzzi, J.; Pollack, James B.; Danielson, G. Edward; Ingersoll, A.; Davies, M.E.; Hunt, G.E.; Masursky, H.; Shoemaker, E.; Morrison, D.; Owen, Timothy W.; Sagan, C.; Veverka, J.; Strom, R.; Suomi, V.E.

    1981-01-01

    As Voyager 1 flew through the Saturn system it returned photographs revealing many new and surprising characteristics of this complicated community of bodies. Saturn's atmosphere has numerous, low-contrast, discrete cloud features and a pattern of circulation significantly different from that of Jupiter. Titan is shrouded in a haze layer that varies in thickness and appearance. Among the icy satellites there is considerable variety in density, albedo, and surface morphology and substantial evidence for endogenic surface modification. Trends in density and crater characteristics are quite unlike those of the Galilean satellites. Small inner satellites, three of which were discovered in Voyager images, interact gravitationally with one another and with the ring particles in ways not observed elsewhere in the solar system. Saturn's broad A, B, and C rings contain hundreds of "ringlets," and in the densest portion of the B ring there are numerous nonaxisymmetric features. The narrow F ring has three components which, in at least one instance, are kinked and crisscrossed. Two rings are observed beyond the F ring, and material is seen between the C ring and the planet. Copyright ?? 1981 AAAS.

  9. Modulation of P450 enzymes by Cuban natural products rich in polyphenolic compounds in rat hepatocytes.

    PubMed

    Rodeiro, I; Donato, M T; Lahoz, A; González-Lavaut, J A; Laguna, A; Castell, J V; Delgado, R; Gómez-Lechón, M J

    2008-03-10

    This paper reports cytotoxic effects and changes in the P450 system after exposing rat hepatocytes to four polyphenol-rich products widely used in Cuban traditional medicine (Mangifera indica L. (MSBE), Thalassia testudinum (Tt), Erythroxylum minutifolium and confusum extracts). Effects of mangiferin, the main polyphenol in MSBE, were also evaluated. Cytotoxicity was assayed by the MTT test after exposure of cells to the products (50-1000 microg/mL) for 24 or 72 h. The results showed that 500 microg/mL MSBE was moderately cytotoxic after 72 h, while mangiferin was not. Marked reductions in cell viability were produced by Erythroxylum extracts at concentrations > or = 200 microg/mL, whereas only moderate effects were induced by 1000 microg/mL Tt. Seven specific P450 activities were evaluated after 48 h exposure of cells to the products. MSBE reduced phenacetin O-deethylation (POD; CYP1A2) activity in a concentration-dependent manner (IC(50)=190 microg/mL). No decreases were observed in other activities. In contrast, mangiferin produced reductions in five P450 activities: IC(50) values of 132, 194, >200, 151 and 137 microg/ml for POD (CYP1A2), midazolam 1'-hydroxylation (M1OH; CYP3A1), diclofenac 4'-hydroxylation (D4OH; CYP2C6), S-mephenytoin 4'-hydroxylation (SM4OH), and chlorzoxazone 6-hydroxyaltion (C6OH; CYP2E1), respectively. E. minutifolium, E. confusum and Tt extracts produced small reductions in SM4OH and C6OH activities, but no significant changes were noted in the other P450 activities. On the other hand, all the products increased the benzyloxyresorufin O-debenzylation (BROD; CYP2B1) activity, with MSBE, mangiferin or E. minutifolium showing the highest effects (about 2-fold over control). Our results showed in vitro effects of these natural products on P450 systems, possibly leading to potential metabolic-based interactions.

  10. [Fluoride in drinking water in Cuba and its association with geological and geographical variables].

    PubMed

    Luna, Liliam Cuéllar; Melián, Maricel García

    2003-11-01

    To determine the association between different concentrations of the fluoride ion in drinking water and some geological and geographical variables in Cuba, by using a geographic information system. From November 1998 to October 1999 we studied the fluoride concentration in the sources of drinking water for 753 Cuban localities that had at least 1 000 inhabitants. For the information analysis we utilized the MapInfo Professional version 5.5 geographic information system, using the overlaying method. The study variables were the concentration of the fluoride ion in the water sources, the geological characteristics of the area, the alignments (geological characteristics that were found together), the types of water sources, and whether an area was a plain or mountainous. The results were grouped by locality and municipality. In 83.1% of the localities, the water samples were collected from wells and springs, and the remaining 16.9% came from dams and rivers. Of the 753 localities studied, 675 of them (89.6%) had low or medium fluoride concentrations (under 0.7 mg/L). The eastern region of the country was the one most affected by high fluoride concentrations in the waters, followed by the central region of the country. The majority of the localities with high natural fluoride concentrations were in areas located on Cretaceous volcanic arc rocks. The presence of fluoride in the drinking waters was related to the alignments with the earth's crust, in rock complexes of volcanic-sedimentary origin and of intrusive origin and also in carbonate rocks. However, the highest fluoride concentrations generally coincided with rock complexes of volcanic-sedimentary origin and of intrusive origin. All the localities with high fluoride concentrations in the water were associated with wells. The fluoride concentration is low or medium in the drinking water sources for 89.6% of the Cuban localities with at least 1 000 inhabitants. Geological and geographical characteristics can help identify areas with optimal or high concentrations of the fluoride ion in the drinking water.

  11. Internal V-Band Clamp

    DOEpatents

    Vaughn, Mark R.; Hafenrichter, Everett S.; Chapa, Agapito C.; Harris, Steven M.; Martinez, Marcus J.; Baty, Roy S.

    2006-02-28

    A system for clamping two tubular members together in an end-to-end relationship uses a split ring with a V-shaped outer rim that can engage a clamping surface on each member. The split ring has a relaxed closed state where the ends of the ring are adjacent and the outside diameter of the split ring is less than the minimum inside diameter of the members at their ends. The members are clamped when the split ring is spread into an elastically stretched position where the ring rim is pressed tightly against the interior surfaces of the members. Mechanisms are provided for removing the spreader so the split ring will return to the relaxed state, releasing the clamped members.

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

    NASA Astrophysics Data System (ADS)

    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.

  13. Ring-Resonator/Sol-Gel Interferometric Immunosensor

    NASA Technical Reports Server (NTRS)

    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.

  14. Saturn's E, G, and F rings - Modulated by the plasma sheet?

    NASA Technical Reports Server (NTRS)

    Morfill, G. E.; Gruen, E.; Johnson, T. V.

    1983-01-01

    Saturn's broad E ring, the narrow G ring, and the structured and apparently time-variable F ring(s) contain many micron and submicron-sized particles, which make up the 'visible' component. These rings (or ring systems) are in direct contact with magnetospheric plasma. Fluctuations in the plasma density and/or mean energy, due to magnetospheric and solar wind processes, may induce stochastic charge variations on the dust particles, which in turn lead to an orbit perturbation and spatial diffusion. In addition, Coulomb drag forces may be important, in particular for the E ring. The possibility that electromagnetic effects may play a role in determining the F ring structure and its possible time variations is critically examined. Sputtering of micron-sized dust particles in the E ring by magnetospheric ions yields lifetimes of 100 to 10,000 years. This effect as well as the plasma induced transport processes require an active source for the E ring, probably Enceladus.

  15. Problems of gaseous motion around stars

    NASA Technical Reports Server (NTRS)

    Huang, S.-S.

    1973-01-01

    A distinction is drawn between radial and tangential modes of ejection from stars, and the possible flow patterns are described. They are: expanding streams, falling streams, jet streams, circulatory streams, and gaseous envelopes. Motion around Be stars is discussed at some length, as a preliminary to studying more complicated flow in binary systems. The rotational velocity of the Be star is insufficient to form the ring. It appears likely that radial instability is temperature sensitive. Rings and disks in binary systems are discussed from the point of view of periodic orbits for particles within the gravitational field of such a system. The formation of these rings is discussed. The expected relation between rotational velocity of the ring and the orbital period is discussed. The relation of circumstellar streams to period changes is mentioned. Finally, the influence of magnetic fields on the circumstellar material and the system is discussed.

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Statistical Ring Catenation under Thermodynamic Control: Should the Jacobson-Stockmayer Cyclization Theory Take into Account Catenane Formation?

    PubMed

    Di Stefano, Stefano; Ercolani, Gianfranco

    2017-01-26

    An extension of the Jacobson-Stockmayer theory is presented to include the reversible formation of [2]catenanes in a ring-chain system under thermodynamic control. The extended theory is based on the molar catenation constant, measuring the ease of catenation of two ring oligomers, whose expression was obtained in a previous work. Two scenarios have been considered: that of "thick" (hydrocarbon-like) chains and that of "thin" (DNA-like) chains. In the case of "thick" chains, the formation of catenanes can be neglected, unless in the unlikely case of a very large value of the equilibrium constant for linear propagation (K ≈ 10 8 mol -1 L, or larger). For K tending to infinity, the system becomes a chain-free system where only ring-catenane equilibria occur. Under this condition, there is a critical concentration below which only rings are present at equilibrium and above which the ring fraction remains constant, and the excess monomer is converted only into catenanes. In the case of "thin" chains, the formation of catenanes cannot be neglected even for values of K as low as 10 2 mol -1 L, thus justifying the use of the extended theory.

  18. Beam diagnostics at high-intensity storage rings

    NASA Astrophysics Data System (ADS)

    Plum, Mike

    1994-10-01

    Beam diagnostics at high-intensity facilities feature their own special set of problems and characteristics, issues peculiar to high-intensity storage rings include beam loss, beam halos, extraction efficiency, beam in the gap, clearing electrodes, and beam-profile measurement. The Los Alamos Proton Storage Ring (PSR) is a nice example of a high-intensity storage ring. I will discuss in some detail three diagnostic systems currently in use at the PSR: the beam-loss-monitor system, the electron-clearing system, and the beam-in-the-gap monitor. Much of our discussion is inspired by the problems we have encountered and the useful things we have learned while commissioning and developing the PSR. Another inspiration is our work on the next-generation neutron-spallation source, also known as the National Center for Neutron Research (NCNR).

  19. Clump detections and limits on moons in Jupiter's ring system.

    PubMed

    Showalter, Mark R; Cheng, Andrew F; Weaver, Harold A; Stern, S Alan; Spencer, John R; Throop, Henry B; Birath, Emma M; Rose, Debi; Moore, Jeffrey M

    2007-10-12

    The dusty jovian ring system must be replenished continuously from embedded source bodies. The New Horizons spacecraft has performed a comprehensive search for kilometer-sized moons within the system, which might have revealed the larger members of this population. No new moons were found, however, indicating a sharp cutoff in the population of jovian bodies smaller than 8-kilometer-radius Adrastea. However, the search revealed two families of clumps in the main ring: one close pair and one cluster of three to five. All orbit within a brighter ringlet just interior to Adrastea. Their properties are very different from those of the few other clumpy rings known; the origin and nonrandom distribution of these features remain unexplained, but resonant confinement by Metis may play a role.

  20. Rotating machinery dynamics simulation. I. Rigid systems with ball bearing nonlinearities and outer ring ovality under rotating unbalance excitation

    PubMed

    el-Saeidy

    2000-02-01

    The radial clearance in rolling bearing systems, required to compensate for dimensional changes associated with thermal expansion of the various parts during operation, may cause dimensional attrition and comprise bearing life, if unloaded operation occurs and balls skid [D. Childs and D. Moyer, ASME J. Eng. Gas Turb. Power 107, 152-159 (1985)]. Also, it can cause jumps in the response to unbalance excitation. These undesirable effects may be eliminated by introducing two or more loops into one of the bearing races so that at least two points of the ring circumference provide a positive zero clearance [D. Childs, Handbook of Rotordynamics, edited by F. Ehrich (McGraw-Hill, NY, 1992)]. The deviation of the outer ring with two loops, known as ovality, is one of the bearing distributed defects. Although this class of imperfections has received much work, none of the available studies has simulated the effect of the outer ring ovality on the dynamic behavior of rotating machinery under rotating unbalance with consideration of ball bearing nonlinearities, shaft elasticity, and speed of rotation. To fill this gap, the equations of motion of a rotor-ball bearing system are formulated using finite-elements (FE) discretization and Lagrange's equations. The analyses are specialized to a rigid-rotor system, by retaining the rigid body modes only in the FE solution. Samples of the results are presented in both time domain and frequency domain for a system with and without outer ring ovality. It is found that with ideal bearings (no ovality), the vibration spectrum is qualitatively and quantitatively the same in both the horizontal and vertical directions. When the ring ovality is introduced, however, the spectrum in both orthogonal planes is no longer similar. And magnitude of the bearing load has increased in the form of repeated random impacts, between balls and rings, in the horizontal direction (direction of maximum clearance) compared to a continuous contact along the vertical direction (direction of positive zero clearance). This underlines the importance of the vibration measuring probe's direction, with respect to the outer ring axes, to capture impact-induced vibrations. Moreover, when the harmonic excitation is increased for a system with ideal bearings, the spectral peaks above forcing frequency have shifted to a higher-frequency region, indicating some sort of a hard spring mechanism inherent in the system. Another observation, is that for the same external excitation, vibration amplitude at forcing frequency in the bearing force spectrum is the same for systems with or without outer ring ovality.

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