147 research outputs found

    Poblaciones y comunidades de algas bentónicas en la costa catalana

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    Las poblaciones de algas bentónicas forman comunidades que en unos lugares están poco diferenciadas y en otros constituyen comunidades definidas de un cierto valor indicativo. En este trabajo se comentan diversos perfiles de la costa catalana, confeccionadas según esquemas tomados sobre el terreno y auxiliados por fotografías submarinas.Los perfiles, tomados en varias localidades de la costa, revelan algunos horizontes y facies característicos del Mediterráneo occidental, lo que nos permite a modo de síntesis, tabular según su exposición al oleaje y a la luz, las facies más conspicuas y mejor caracterizadas.The populations of benthic algae form communities which are little differenciated in some spots while in others they constitute definite communities with some indicative value. Several profiles of the catalan coast are treated in this paper they have been drawn in accordance with outlines taken on the ground and with the aid of submarine pictures.The profiles, taken at several spots of the coast, reveal some horizonts and facieswhich are characteristic of the west Mediterranean, this allows us to tabulate the facies more evidents and better characterized according to their exposure to the swell and to the light

    Poblaciones y comunidades de algas bentónicas en la costa catalana

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    The populations of benthic algae form communities which are little differenciated in some spots while in others they constitute definite communities with some indicative value. Several profiles of the catalan coast are treated in this paper they have been drawn in accordance with outlines taken on the ground and with the aid of submarine pictures. The profiles, taken at several spots of the coast, reveal some horizonts and facies which are characteristic of the west Mediterranean, this allows us to tabulate the facies more evidents and better characterized according to their exposure to the swell and to the light.Las poblaciones de algas bentónicas forman comunidades que en unos lugares están poco diferenciadas y en otros constituyen comunidades definidas de un cierto valor indicativo. En este trabajo se comentan diversos perfiles de la costa catalana, confeccionadas según esquemas tomados sobre el terreno y auxiliados por fotografías submarinas. Los perfiles, tomados en varias localidades de la costa, revelan algunos horizontes y facies característicos del Mediterráneo occidental, lo que nos permite a modo de síntesis, tabular según su exposición al oleaje y a la luz, las facies más conspicuas y mejor caracterizadas

    Academic Self-Concept of Secondary Science Education Students: A Structural Equation Modeling Approach

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    Academic self-concept (ASC), a construct recognized in education and psychology, is a significant factor influencing academic performance. Although numerous reports have examined college students' academic self-concept globally, little research has been conducted to ascertain the underlying factor structure and constructs of ASC among undergraduate secondary science majors in the Philippines. The primary objectives of this study were to examine the ASC of BSED college students and to ascertain the underlying factor structure of the ASC variables. The survey of 94 BSED Science students revealed an average general ASC. The EFA model revealed a two-factor structure for the observed variables. The SEM indicates a slight negative correlation between Positive ASC and Negative ASC. Students' sense of capability, pride in their college grades, and belief that studying hard pays off are all strongly associated with the Positive ACS. Students' feelings of being behind on classwork and a lack of necessary abilities for specific majors are heavily attributed to the negative ACS. According to the generated values for the model's good fit indices, the ACS SEM model of the study is an acceptable model. Additional research shall be conducted to further our understanding of students' Academic Self-concepts across disciplines and to validate the two-factor structure model developed in this study

    Warming and CO2 Enhance Arctic Heterotrophic Microbial Activity

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    Ocean acidification and warming are two main consequences of climate change that can directly affect biological and ecosystem processes in marine habitats. The Arctic Ocean is the region of the world experiencing climate change at the steepest rate compared with other latitudes. Since marine planktonic microorganisms play a key role in the biogeochemical cycles in the ocean it is crucial to simultaneously evaluate the effect of warming and increasing CO2 on marine microbial communities. In 20 L experimental microcosms filled with water from a high-Arctic fjord (Svalbard), we examined changes in phototrophic and heterotrophic microbial abundances and processes [bacterial production (BP) and mortality], and viral activity (lytic and lysogenic) in relation to warming and elevated CO2. The summer microbial plankton community living at 1.4°C in situ temperature, was exposed to increased CO2 concentrations (135–2,318 μatm) in three controlled temperature treatments (1, 6, and 10°C) at the UNIS installations in Longyearbyen (Svalbard), in summer 2010. Results showed that chlorophyll a concentration decreased at increasing temperatures, while BP significantly increased with pCO2 at 6 and 10°C. Lytic viral production was not affected by changes in pCO2 and temperature, while lysogeny increased significantly at increasing levels of pCO2, especially at 10°C (R2 = 0.858, p = 0.02). Moreover, protistan grazing rates showed a positive interaction between pCO2 and temperature. The averaged percentage of bacteria grazed per day was higher (19.56 ± 2.77% d-1) than the averaged percentage of lysed bacteria by virus (7.18 ± 1.50% d-1) for all treatments. Furthermore, the relationship among microbial abundances and processes showed that BP was significantly related to phototrophic pico/nanoflagellate abundance in the 1°C and the 6°C treatments, and BP triggered viral activity, mainly lysogeny at 6 and 10°C, while bacterial mortality rates was significantly related to bacterial abundances at 6°C. Consequently, our experimental results suggested that future increases in water temperature and pCO2 in Arctic waters will produce a decrease of phytoplankton biomass, enhancement of BP and changes in the carbon fluxes within the microbial food web. All these heterotrophic processes will contribute to weakening the CO2 sink capacity of the Arctic plankton community.En prens

    Разработка технологии и проектирование участка сборки-сварки траверсы задней крепи механизированной МКЮ4У.56

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    Актуальность работы: в данной выпускной квалификационной работе производится проектирование участка сборки-сварки траверсы задней крепи механизированной МКЮ4У.56. Объектом исследования является процесс изготовления траверсы. Цели и задачи исследования (работы). В результате данной работы следует получить производство с наибольшей степенью механизации и автоматизации повышающей производительность труда. Работа представлена введением, пятью разделами (главами) и заключением, приведен список использованных источников.Relevance of the work: in the final qualifying work is done tooling design and site assembly welding traverses back lining mechanized MKY 4U.56. The object of research is the process of making the traverse. The aims and objectives of the study (work). As a result of this work should be obtained from producing the greatest degree of mechanization and automation increases productivity. The work provides an introduction, five sections (chapters) and conclusion, a list of sources used

    Depression in internal medicine inpatients at the time of hospital discharge and referral to primary care

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    Background and objectives: This is the first multi-center study intended to document the prevalence, characteristics, and associations of depression in Medicine patients at the time of hospital discharge and their referral to Primary Care (PC). Methods: Adult patients randomly selected among consecutive admissions to Medicine wards in 8 hospitals in Spain, covering health districts, were examined in a two-phase ''case-finding'' procedure. Standardized, Spanish versions of instruments were used, including the Standardized Polyvalent Psychiatric Interview (SPPI) and Cumulative Illness Rating Scale (CIRS). Cases of depression were diagnosed according to ICD-10 general hospital research criteria. Results: Three hundred and twelve patients with treatable depression and 777 non-depressed controls were identified. In a conservative estimate, the global prevalence of major depression was 7.1%, dysthymia 4.2% and adjustment depression 7.1%, and 51.9% of cases were of moderate/ severe intensity. Depression was more frequent in women, the differences being significant in all categories of depression. The prevalence of depression was lower in individuals aged 85 or more years, the differences being significant in cases of both dysthymia and adjustment depression. A clear pattern of decreasing prevalence with age was observed in women. The depressed had as an average five medical systems affected, and higher CIRS scores compared with the controls, the differences being significant in cases of both major depression and dysthymia. Conclusions: This is the first report showing a considerable prevalence of treatable cases of depression in Medicine patients at the time of hospital discharge and referral to PC. Depression is associated with the severity of the medical condition, and differences observed by age and sex have clinical implications. Paper read at the 3rd Annual Meeting of the European Association of Psychosomatic Medicine, Nuremberg 2015. © 2022 Asociación Universitaria de Zaragoza para el Progreso de la Psiquiatría y la Salud Menta

    Synchronous communication in PLM environments using annotated CAD models

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    The connection of resources, data, and knowledge through communication technology plays a vital role in current collaborative design methodologies and Product Lifecycle Management (PLM) systems, as these elements act as channels for information and meaning. Despite significant advances in the area of PLM, most communication tools are used as separate services that are disconnected from existing development environments. Consequently, during a communication session, the specific elements being discussed are usually not linked to the context of the discussion, which may result in important information getting lost or becoming difficult to access. In this paper, we present a method to add synchronous communication functionality to a PLM system based on annotated information embedded in the CAD model. 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    Engineering HIV-1-resistant T-cells from short-hairpin RNA-expressing hematopoietic stem/progenitor cells in humanized BLT mice

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    Down-regulation of the HIV-1 coreceptor CCR5 holds significant potential for long-term protection against HIV-1 in patients. Using the humanized bone marrow/liver/thymus (hu-BLT) mouse model which allows investigation of human hematopoietic stem/progenitor cell (HSPC) transplant and immune system reconstitution as well as HIV-1 infection, we previously demonstrated stable inhibition of CCR5 expression in systemic lymphoid tissues via transplantation of HSPCs genetically modified by lentiviral vector transduction to express short hairpin RNA (shRNA). However, CCR5 down-regulation will not be effective against existing CXCR4-tropic HIV-1 and emergence of resistant viral strains. As such, combination approaches targeting additional steps in the virus lifecycle are required. We screened a panel of previously published shRNAs targeting highly conserved regions and identified a potent shRNA targeting the R-region of the HIV-1 long terminal repeat (LTR). Here, we report that human CD4+ T-cells derived from transplanted HSPC engineered to co-express shRNAs targeting CCR5 and HIV-1 LTR are resistant to CCR5- and CXCR4- tropic HIV-1-mediated depletion in vivo. Transduction with the combination vector suppressed CXCR4- and CCR5- tropic viral replication in cell lines and peripheral blood mononuclear cells in vitro. No obvious cytotoxicity or interferon response was observed. Transplantation of combination vector-transduced HSPC into hu-BLT mice resulted in efficient engraftment and subsequent stable gene marking and CCR5 down-regulation in human CD4+ T-cells within peripheral blood and systemic lymphoid tissues, including gut-associated lymphoid tissue, a major site of robust viral replication, for over twelve weeks. CXCR4- and CCR5- tropic HIV-1 infection was effectively inhibited in hu-BLT mouse spleen-derived human CD4+ T-cells ex vivo. Furthermore, levels of gene-marked CD4+ T-cells in peripheral blood increased despite systemic infection with either CXCR4- or CCR5- tropic HIV-1 in vivo. These results demonstrate that transplantation of HSPCs engineered with our combination shRNA vector may be a potential therapy against HIV disease.This work was supported by grants from the California Institute for Regenerative Medicine (CIRM grant DR1-01431 to ISYC), the National Institutes of Health (1RO1HL086409 and 3RO1HL086409-03S1 to DSA and 5T32AI060567), and the University of California Los Angeles AIDS Institute/Center for AIDS Research (5P30AI028697). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
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