303 research outputs found
Improved measurement results for the Avogadro constant using a 28Si-enriched crystal
New results are reported from an ongoing international research effort to
accurately determine the Avogadro constant by counting the atoms in an
isotopically enriched silicon crystal. The surfaces of two 28Si-enriched
spheres were decontaminated and reworked in order to produce an outer surface
without metal contamination and improved sphericity. New measurements were then
made on these two reconditioned spheres using improved methods and apparatuses.
When combined with other recently refined parameter measurements, the Avogadro
constant derived from these new results has a value of mol. The X-ray crystal density method has thus achieved
the target relative standard uncertainty of necessary for
the realization of the definition of the new kilogram.Comment: postprint, 22 page, 3 figures, 14 table
Lymphocyte Modulation with FTY720 Improves Hemorrhagic Shock Survival in Swine
The inflammatory response to severe traumatic injury results in significant morbidity and mortality. Lymphocytes have recently been identified as critical mediators of the early innate immune response to ischemia-reperfusion injury. Experimental manipulation of lymphocytes following hemorrhagic shock may prevent secondary immunologic injury in surgical and trauma patients. The objective of this study is to evaluate the lymphocyte sequestration agent FTY720 as an immunomodulator following experimental hemorrhagic shock in a swine liver injury model. Yorkshire swine were anesthetized and underwent a grade III liver injury with uncontrolled hemorrhage to induce hemorrhagic shock. Experimental groups were treated with a lymphocyte sequestration agent, FTY720, (n = 9) and compared to a vehicle control group (n = 9). Animals were observed over a 3 day survival period after hemorrhage. Circulating total leukocyte and neutrophil counts were measured. Central lymphocytes were evaluated with mesenteric lymph node and spleen immunohistochemistry (IHC) staining for CD3. Lung tissue infiltrating neutrophils were analyzed with myeloperoxidase (MPO) IHC staining. Relevant immune-related gene expression from liver tissue was quantified using RT-PCR. The overall survival was 22.2% in the vehicle control and 66.7% in the FTY720 groups (p = 0.081), and reperfusion survival (period after hemorrhage) was 25% in the vehicle control and 75% in the FTY720 groups (p = 0.047). CD3+ lymphocytes were significantly increased in mesenteric lymph nodes and spleen in the FTY720 group compared to vehicle control, indicating central lymphocyte sequestration. Lymphocyte disruption significantly decreased circulating and lung tissue infiltrating neutrophils, and decreased expression of liver immune-related gene expression in the FTY720 treated group. There were no observed infectious or wound healing complications. Lymphocyte sequestration with FTY720 improves survival in experimental hemorrhagic shock using a porcine liver injury model. These results support a novel and clinically relevant lymphocyte immunomodulation strategy to ameliorate secondary immune injury in hemorrhagic shock
Enhanced surface water flood forecasts: User-led development and testing
The risk of surface water flooding (SWF) in England is already high and its frequency and severity is projected to increase in the future. SWF generally occurs due to intense, highly localised rainfall, which is challenging to forecast with sufficient accuracy to take proactive action ahead of flood events. Being able to manage the risk effectively lies in improved rainfall and flood forecast products, better communication of uncertainty and building the capacity of local responders. This study utilises state-of-the-art high-resolution ensemble rainfall forecasts and hydraulic modelling tools alongside a novel post-processing method to develop and trial new SWF forecast products within an incident workshop attended by forecast producers and regional forecast users. Twenty-two of 24 workshop participants reported that the new information would be useful to their organisation but more product development and training in its interpretation is required. Specific recommendations to improve SWF forecast provision include increased support for local government through a single government organisation responsible for SWF, making more use of existing static SWF mapping in a real-time context and employing the process of user-based consultation, as outlined in this study, to guide the future development of future SWF forecast information and processes
Brabykinin B1 Receptor Antagonism Is Beneficial in Renal Ischemia-Reperfusion Injury
Previously we have demonstrated that bradykinin B1 receptor deficient mice (B1KO) were protected against renal ischemia and reperfusion injury (IRI). Here, we aimed to analyze the effect of B1 antagonism on renal IRI and to study whether B1R knockout or antagonism could modulate the renal expression of pro and anti-inflammatory molecules. To this end, mice were subjected to 45 minutes ischemia and reperfused at 4, 24, 48 and 120 hours. Wild-type mice were treated intra-peritoneally with antagonists of either B1 (R-954, 200 µg/kg) or B2 receptor (HOE140, 200 µg/kg) 30 minutes prior to ischemia. Blood samples were collected to ascertain serum creatinine level, and kidneys were harvested for gene transcript analyses by real-time PCR. Herein, B1R antagonism (R-954) was able to decrease serum creatinine levels, whereas B2R antagonism had no effect. The protection seen under B1R deletion or antagonism was associated with an increased expression of GATA-3, IL-4 and IL-10 and a decreased T-bet and IL-1β transcription. Moreover, treatment with R-954 resulted in lower MCP-1, and higher HO-1 expression. Our results demonstrated that bradykinin B1R antagonism is beneficial in renal IRI
Vascular phenotype in angiogenic and non-angiogenic lung non-small cell carcinomas
We have previously described a group of non-small cell lung carcinomas without morphological evidence of neo-angiogenesis. In these tumours neoplastic cells fill up the alveoli and the only vessels present appear to belong to the trapped alveolar septa. In the present study we have characterised the phenotype of the vessels present in these non-angiogenic tumours, in normal lung and in angiogenic non-small cell lung carcinomas. The vessels, identified by the expression of CD31, were scored as mature when expressing the epitope LH39 in the basal membrane and as newly formed when expressing αVβ3 on the endothelial cells and/or lacking LH39 expression. In the nine putative non-angiogenic cases examined, the vascular phenotype of all the vessels was the same as that of alveolar vessels in normal lung: LH39 positive and αVβ3 variable or negative. Instead in 104 angiogenic tumours examined, only a minority of vessels (mean 13.1%; range 0–60%) expressed LH39, while αVβ3 (in 45 cases) was strongly expressed on many vessels (mean 55.5%; range 5–90%). We conclude that in putative non-angiogenic tumours the vascular phenotype is that of normal vessels and there is no neo-angiogenesis. This type of cancer may be resistant to some anti-angiogenic therapy and different strategies need to be developed
Report of the key comparison CCQM-K88 : determination of lead in lead-free solder containing silver and copper
The CCQM-K88 key comparison was organised by the Inorganic Analysis Working Group of CCQM to test the abilities of the national metrology institutes to measure the mass fraction of lead in lead-free solder containing silver and copper. National Metrology Institute of Japan (NMIJ), National Institute of Metrology P. R. China (NIM) and Korea Research Institute of Standards and Science (KRISS) acted as the coordinating laboratories. The participants used different measurement methods, though most of them used inductively coupled plasma optical emission spectrometry (ICP-OES) or isotope-dilution inductively coupled plasma mass spectrometry (ID-ICP-MS). Accounting for relative expanded uncertainty, comparability of measurement results was successfully demonstrated by the participating NMIs for the measurement of the mass fraction of lead in lead-free solder at the level of 200 mg/kg. It is expected that metals at mass fractions greater than approximately100 mg/kg in lead-free solder containing silver and copper can be determined by each participant using the same technique(s) employed for this key comparison to achieve similar uncertainties mentioned in the present report.Fil: Hioki, Akiharu. National Metrology Institute of Japan (NMIJ); JapónFil: Nonose, Naoko. National Metrology Institute of Japan (NMIJ); JapónFil: Liandi, Ma. National Institute of Metrology (NIM); ChinaFil: Jingbo, Chao. National Institute of Metrology (NIM); ChinaFil: Liuxing, Feng. National Institute of Metrology (NIM); ChinaFil: Chao, Wei. National Institute of Metrology (NIM); ChinaFil: Cho, Kyung Haeng. Korea Research Institute of Standards and Science (KRISS); Corea del SurFil: Suh, Jung Ki. Korea Research Institute of Standards and Science (KRISS); Corea del SurFil: Min, Hyung Sik. Korea Research Institute of Standards and Science (KRISS); Corea del SurFil: Lim, Youngran. Korea Research Institute of Standards and Science (KRISS); Corea del SurFil: Recknagel, Sebastian. Federal Institute for Materials Research and Testing (BAM); AlemaniaFil: Koenig, Maren. Federal Institute for Materials Research and Testing (BAM); AlemaniaFil: Vogl, Jochen. Federal Institute for Materials Research and Testing (BAM); AlemaniaFil: Caciano de Sena, Rodrigo. Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMetro); BrasilFil: dos Reis, Lindomar Augusto. Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMetro); BrasilFil: Borinsky, Mónica. Instituto Nacional de Tecnología Industrial (INTI); ArgentinaFil: Puelles, Mabel. Instituto Nacional de Tecnología Industrial (INTI); ArgentinaFil: Hatamleh, Nadia. Instituto Nacional de Tecnología Industrial (INTI); ArgentinaFil: Acosta, Osvaldo. Instituto Nacional de Tecnología Industrial (INTI); ArgentinaFil: Turk, Gregory. National Institute of Standards and Technology (NIST); Estados UnidosFil: Rabb, Savelas. National Institute of Standards and Technology (NIST); Estados UnidosFil: Sturgeon, Ralph. National Research Council (NRC); CanadáFil: Methven, Brad. National Research Council (NRC); CanadáFil: Rienitz, Olaf. Physikalisch-Technische Bundesanstalt (PTB); AlemaniaFil: Jaehrling, Reinhard. Physikalisch-Technische Bundesanstalt (PTB); AlemaniaFil: Konopelko, L. A. D. I. Mendeleev Institute for Metrology (VNIIM); RusiaFil: Kustikov, Yu. A. D. I. Mendeleev Institute for Metrology (VNIIM); RusiaFil: Kozyreva, S. B. D. I. Mendeleev Institute for Metrology (VNIIM); RusiaFil: Korzh, A. A. D. I. Mendeleev Institute for Metrology (VNIIM); Rusi
Reversal to air-driven sound production revealed by a molecular phylogeny of tongueless frogs, family Pipidae
<p>Abstract</p> <p>Background</p> <p>Evolutionary novelties often appear by conferring completely new functions to pre-existing structures or by innovating the mechanism through which a particular function is performed. Sound production plays a central role in the behavior of frogs, which use their calls to delimit territories and attract mates. Therefore, frogs have evolved complex vocal structures capable of producing a wide variety of advertising sounds. It is generally acknowledged that most frogs call by moving an air column from the lungs through the glottis with the remarkable exception of the family Pipidae, whose members share a highly specialized sound production mechanism independent of air movement.</p> <p>Results</p> <p>Here, we performed behavioral observations in the poorly known African pipid genus <it>Pseudhymenochirus </it>and document that the sound production in this aquatic frog is almost certainly air-driven. However, morphological comparisons revealed an indisputable pipid nature of <it>Pseudhymenochirus </it>larynx. To place this paradoxical pattern into an evolutionary framework, we reconstructed robust molecular phylogenies of pipids based on complete mitochondrial genomes and nine nuclear protein-coding genes that coincided in placing <it>Pseudhymenochirus </it>nested among other pipids.</p> <p>Conclusions</p> <p>We conclude that although <it>Pseudhymenochirus </it>probably has evolved a reversal to the ancestral non-pipid condition of air-driven sound production, the mechanism through which it occurs is an evolutionary innovation based on the derived larynx of pipids. This strengthens the idea that evolutionary solutions to functional problems often emerge based on previous structures, and for this reason, innovations largely depend on possibilities and constraints predefined by the particular history of each lineage.</p
Interdisciplinary project-based learning: technology for improving student cognition
The article studies a way of enhancing student cognition by using interdisciplinary project-based learning (IPBL) in a higher education institution. IPBL is a creative pedagogic approach allowing students of one area of specialisation to develop projects for students with different academic profiles. The application of this approach in the Ural State University of Economics resulted in a computer-assisted learning system (CALS) designed by IT students. The CALS was used in an analytical chemistry course with students majoring in Commodities Management and Expertise (‘expert’ students). To test how effective the technology was, the control and experimental groups were formed. In the control group, learning was done with traditional methods. In the experimental group, it was reinforced by IPBL. A statistical analysis of the results, with an application of Pearson χ 2 test, showed that the cognitive levels in both IT and ‘expert’ experimental groups improved as compared with the control groups. The findings demonstrated that IPBL can significantly enhance learning. It can be implemented in any institution of higher or secondary education that promotes learning, including the CALS development and its use for solving problems in different subject areas
Breeding amphibians in captivity
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73877/1/j.1748-1090.1977.tb00864.x.pd
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