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181.
Size–weight relationships of batoids captured by artisanal fishery in the southern Gulf of California,Mexico
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N. R. Ehemann X. A. Pérez‐Palafox P. Mora‐Zamacona M. I. Burgos‐Vázquez A. F. Navia P. A. Mejía‐Falla V. H. Cruz‐Escalona 《Zeitschrift fur angewandte Ichthyologie》2017,33(5):1051-1054
This study reports the size–weight relationships (SWR) for nine batoid species that are frequently fished by the artisanal fisheries in the southern Gulf of California. Analysis included a total of 2,012 specimens, caught from October 2013 to July 2016. The slope values (b) oscillated from 2.80 to 3.56. Growth was isometric for five species and positively allometric for four. There were differences in SWR between sexes for three species being in all cases the female greater and heavier than males. This is the first analysis of SWR for the batoid species studied in the Gulf of California. 相似文献
182.
Excess mortality in persons with severe mental disorders: a multilevel intervention framework and priorities for clinical practice,policy and research agendas
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Nancy H. Liu Gail L. Daumit Tarun Dua Ralph Aquila Fiona Charlson Pim Cuijpers Benjamin Druss Kenn Dudek Melvyn Freeman Chiyo Fujii Wolfgang Gaebel Ulrich Hegerl Itzhak Levav Thomas Munk Laursen Hong Ma Mario Maj Maria Elena Medina‐Mora Merete Nordentoft Dorairaj Prabhakaran Karen Pratt Martin Prince Thara Rangaswamy David Shiers Ezra Susser Graham Thornicroft Kristian Wahlbeck Abe Fekadu Wassie Harvey Whiteford Shekhar Saxena 《World psychiatry》2017,16(1):30-40
Excess mortality in persons with severe mental disorders (SMD) is a major public health challenge that warrants action. The number and scope of truly tested interventions in this area remain limited, and strategies for implementation and scaling up of programmes with a strong evidence base are scarce. Furthermore, the majority of available interventions focus on a single or an otherwise limited number of risk factors. Here we present a multilevel model highlighting risk factors for excess mortality in persons with SMD at the individual, health system and socio‐environmental levels. Informed by that model, we describe a comprehensive framework that may be useful for designing, implementing and evaluating interventions and programmes to reduce excess mortality in persons with SMD. This framework includes individual‐focused, health system‐focused, and community level and policy‐focused interventions. Incorporating lessons learned from the multilevel model of risk and the comprehensive intervention framework, we identify priorities for clinical practice, policy and research agendas. 相似文献
183.
184.
Azhar Fakharuddin Lukas Schmidt‐Mende Germà Garcia‐Belmonte Rajan Jose Ivan Mora‐Sero 《Liver Transplantation》2017,7(22)
Rapid improvement in photoconversion efficiency (PCE) of solution processable organometallic hybrid halide based perovskite solar cells (PSCs) have taken the photovoltaic (PV) community with a surprise and has extended their application in other electronic devices such as light emitting diodes, photo detectors and batteries. Together with efforts to push the PCE of PSCs to record values >22% – now at par with that of crystalline silicon solar cells – origin of their PV action and underlying physical processes are also deeply investigated worldwide in diverse device configurations. A typical PSC consists of a perovskite film sandwiched between an electron and a hole selective contact thereby creating ESC/perovskite and perovskite/HSC interfaces, respectively. The selective contacts and their interfaces determine properties of perovskite layer and also control the performance, origin of PV action, open circuit voltage, device stability, and hysteresis in PSCs. Herein, we define ideal charge selective contacts, and provide an overview on how the choice of interfacing materials impacts charge accumulation, transport, transfer/recombination, band‐alignment, and electrical stability in PSCs. We then discuss device related considerations such as morphology of the selective contacts (planar or mesoporous), energetics and electrical properties (insulating and conducting), and its chemical properties (organic vs inorganic). Finally, the outlook highlights key challenges and future directions for a commercially viable perovskite based PV technology. 相似文献
185.
Michael S. Engel Diying Huang Abdulaziz S. Alqarni Chenyang Cai Mabel Alvarado Laura C.V. Breitkreuz Dany Azar 《Comptes Rendus Palevol》2017,16(1):5-11
A remarkably specialized parasitoid wasp of the family Scelionidae (Platygastroidea) is described and figured from mid-Cretaceous (Cenomanian) amber of the Hukawng Valley in northern Myanmar. Geoscelio mckellari Engel and Huang, gen. et sp. nov., is unique for its combination of a compact body, 12 antennal flagellomeres, a 1-2-2 tibial spur formula, a distinct malar sulcus, deeply impressed notauli, complete reduction of the wings, and basal crenulae on the metasomal terga and sterna, among many other features, and is placed within a separate tribe, Geoscelionini Engel and Huang, trib. nov. This is the first flightless species of Platygastroidea known from the Mesozoic, and its affinities with other Mesozoic and extant lineages are discussed. 相似文献
186.
Glutamine Synthesis Is Essential for Growth of Streptococcus thermophilus in Milk and Is Linked to Urea Catabolism
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Growth of a glutamine synthetase-deficient mutant of Streptococcus thermophilus was compared to that of the parent strain in milk that was not supplemented or was supplemented with ammonium chloride, glutamine, or the urease inhibitor flurofamide. It was concluded that one of the functions of urease is to supply ammonia for the synthesis of glutamine. 相似文献
187.
In order to study both the hunting efficiency and the flexibility of their predatory behavior, solitary hunters of the trap-jaw ant Odontomachus opaciventris were offered small prey (termites, fruit flies and tenebrionid larvae), presenting different morphological or defensive characteristics. The monomorphic hunters showed a moderately flexible predatory behavior characterized by short capture sequences and a noteworthy efficiency of their mandible strike (76.7-100% of prey retrievals), even when presented with Nasutitermes soldiers. Contrary to most poneromorph ants, antennal palpation of the prey before the attack was always missing, no particular targeted region of the prey's body was preferred, and no 'prudent' posture was ever exhibited. Moreover, stinging was regularly performed on bulky, fast moving fruit flies, very scarcely with sclerotized tenebrionid larvae, but never occurred with Nasutitermes workers or soldiers despite their noxious chemical defense. These results suggest that, whatever the risk linked to potentially dangerous prey, O. opaciventris predatory strategy optimizes venom use giving top priority to the swiftness and strength of the lethal trap-jaw system used by hunters as first strike weapon to subdue rapidly a variety of small prey, ranging from 0.3 to 2 times their own body size and from 0.1 to 2 times their weight. Such risk-prone predatory behavior is likely to be related to the large size of O. opaciventris colonies where the death of a forager might be of lesser vital outcome than in small colony-size species. 相似文献
188.
DNA dendrimers, conjugated with both anti-biotin antibodies and up to 350 labeling entities, were designed and adapted to protein microarray and enzyme-linked immunosorbent assay (ELISA) to improve the limits of protein detection with no additional steps or equipment. Application of conjugated dendrimers to standard ELISA cytokine detection resulted in up to threefold improvement of the limits of detection with no significant increase in the inter- and intra-assay coefficient of variation (CV) compared to streptavidin horseradish peroxidase (SA-HRP) detection. The adaptation of conjugated dendrimers to protein microarray cytokine detection resulted in up to 10-fold improvement of the limits of detection, but assay conditions would have to be optimized to decrease the intra- and inter-assay %CVs. 相似文献
189.
The roles played by singlet oxygen (1O2) in photodynamic therapy are not fully understood yet. In particular, the mobility of 1O2 within cells has been a subject of debate for the last two decades. In this work, we report on the kinetics of 1O2 formation, diffusion, and decay in human skin fibroblasts. 1O2 has been photosensitized by two water-soluble porphyrins targeting different subcellular organelles, namely the nucleus and lysosomes, respectively. By recording the time-resolved near-IR phosphorescence of 1O2 and that of its precursor the photosensitizer's triplet state, we find that the kinetics of singlet oxygen formation and decay are strongly dependent on the site of generation. 1O2 photosensitized in the nucleus is able to escape out of the cells while 1O2 photosensitized in the lysosomes is not. Despite showing a lifetime in the microsecond time domain, 1O2 decay is largely governed by interactions with the biomolecules within the organelle where it is produced. This observation may reconcile earlier views that singlet oxygen-induced photodamage is highly localized, while its lifetime is long enough to diffuse over long distances within the cells. 相似文献
190.
Fernández V Tapia G Varela P Gaete L Vera G Mora C Vial MT Videla LA 《Free radical biology & medicine》2008,44(9):1724-1731
Hepatic ischemia-reperfusion (IR) injury, a major clinical drawback during surgery, is abolished by L-3,3',5-triiodothyronine (T(3)) administration. Considering that the triggering mechanisms are unknown, the aim of this study is to assess the role of oxidative stress in T(3) preconditioning using N-acetylcysteine (NAC) before T(3) administration. Male Sprague-Dawley rats given a single dose of 0.1 mg of T(3)/kg were subjected to 1 h ischemia followed by 20 h reperfusion, in groups of animals pretreated with 0.5 g of NAC/kg 0.5 h before T(3) or with the respective control vehicles. At the end of the reperfusion period, blood and liver samples were taken for analysis of serum aspartate aminotransferase (AST) and hepatic histology, glutathione (GSH) and protein carbonyl contents, and nuclear factor-kappaB (NF-kappaB) and activating protein 1 (AP-1) DNA binding. The IR protocol used led to a 4.5-fold increase in serum AST levels and drastic changes in liver histology, with significant GSH depletion and enhancement of protein carbonyl levels and of the protein carbonyl/GSH content ratio, whereas NF-kappaB and AP-1 DNA binding was decreased and enhanced, respectively. In a time window of 48 h, T(3) exerted protection against hepatic IR injury, with 88% reduction in the protein carbonyl/GSH ratio and normalization of NF-kappaB and AP-1 DNA binding, changes that were suppressed by NAC administration before T(3). Data presented suggest that a transient increase in the oxidative stress status of the liver is an important trigger for T(3) preconditioning, evidenced in a warm IR injury model through antioxidant intervention. 相似文献