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black Sun: Ocular Invisibility of Relativistic Luminous Astrophysical bodies

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Journal of High Energy Physics, Gravitation and Cosmology 2016年第4期2卷 562-570页

作者： jeffrey S. Lee Gerald b. Cleaver Early Universe Cosmology and Strings Group Center for Astrophysics Space Physics and Engineering Research Waco TX USA Department of Physics Baylor University Waco TX USA

Considered as a gedanken experiment are the conditions under which the relativistic Doppler shifting of visible electromagnetic radiation to beyond the human ocular range could reduce the incident radiance of the source, and render a luminous astrophysical body (LAb) invisible to a naked eye. This paper determines the proper distance as a function of relativistic velocity at which a luminous object attains ocular invisibility.

关键词： Relativistic Processes black Hole Physics Reference Systems Luminous Astrophysical body Relativistic blackbody Spectrum

Mass Screening Using Antigenic and Molecular Diagnostic Tests of COVID-19 in bangui at the beginning of the Second Wave in July 2021

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Journal of Tuberculosis Research 2024年第1期12卷 1-12页

作者： Clotaire Donatien Rafaï Marie-Roseline Darnycka belizaire Pierre Somse Wilfrid Sylvain Nambei Ernest Lango-Yaya Oscar Senzongo Luc Salva Hereidebona Ulrich jeffrey Kotemossoua Rabbi Mermoz Senekian Simon Pounguinza Christian-Diamant Mossoro-Kpinde Alain Le Faou Jean De Dieu Longo François-Xavier Mbopi-Keou Gérard Grésenguet boniface Koffi National Laboratory of Clinical biology and Public Health Bangui Central African Republic Faculty of Health Sciences University of Bangui Bangui Central African Republic World Health Organization Bangui Central African Republic Ministry of Health and Population Bangui Central African Republic Faculty of Medicine Maieutic and Health Sciences University of Lorraine Pole Brabois Santé Nancy France Faculty of Medicine and biomedical Sciences University of Yaounde I Yaounde Cameroun

Objective: COVID-19 surveillance was established as early as March 2020 in the Central African Republic (CAR), after the WHO statement relating to the identification of several cases outside China. However, given the non-performing molecular biology technical platform in many developing countries in sub-Saharan Africa, the second wave promised to be surprising and formidable. In this context, a mass survey was launched in bangui to determine the prevalence of COVID-19. Patients and Methods: From March 18 to April 2, 2021, a mass screening campaign took place in tourist places, companies and the main hospital infrastructures. Nasopharyngeal swab samples were collected from participants with and without symptoms of Influenza-like illness (ILI) and stored in VTM tubes. The Ag (COVID-19) and RT-PCR tests were carried out in bangui at the LNbCSP. The sequencing of RT-PCR SARS-CoV-2 positives was carried out at the INRb. Results: We included 1480 participants of whom 33 (2.23%) were SARS-COV-2 positive, of whom 24 were male and 9 female. This sex difference was statistically significant (p = 0.012) as the sex ratio M/F was 1.09. Sampling sites located in the 1st arrondissement were the most prolific (p = 0.006) and were sequenced. In addition to the analysis of the 33 samples from the predefined sites under study, 17 control sequences from the provinces generated during the same period are added. We detected 2 Variants Of Concern (VOC) including the predominant b.1.620 (43.86%) followed by b.1.1.7 or Alpha (5.10%). Conclusion: The study showed the importance of surveillance and the availability of means of diagnosis of COVID-19. The identified risk factors were sex and sampling site. This study has shown the importance of setting up sentinel sites for COVID-19 surveillance in all regions of the country and the appropriate use of the anti-COVID-19 vaccine.

关键词： COVID-19 Variants Central African Republic

Revisiting the Plant＇s Dilemma

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Molecular Plant 2016年第1期9卷 7-9页

作者： jeffrey Leung Nadia bazihizina Stefano Mancuso Christiane Valon Institut de biologie Inté grative de la Cellule Universit&eacute de Paris Saclay-Centre d'Energie Atomique Centre National de la Recherche Scientifique UMR9198 1 Avenue de la Terrasse B&acirc timent 23 91198 Gif-sur-Yvette Cedex France LINV-DISPAA Universit&agrave degli Studi di Firenze Viale delle idee 30 50019 Sesto Fiorentino Italy

In the opening salvos of his engaging article, How Stomata Resolve the Dilemma of Opposing Priorities, Raschke （1976） wrote that “Land plants are in a dilemma throughout their lives： assimilation of CO2 from the atmosphere requires intensive gas exchange; the prevention of excessive water loss demands that gas exchange be kept low.” What seemed a rarefied musing of a plant academic nearly 40 years ago has since broadened into alobal environmental concerns.

关键词： AbSCISIC-ACID CO2

Quantification and pharmacokinetic study of tumor-targeting agent MHI148-clorgyline amide in mouse plasma using liquid chromatography-electrospray ionization tandem mass spectrometry

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Journal of Pharmaceutical Analysis 2018年第3期8卷 153-159页

作者： Zhijun Wang bogdan Z.Olenyuk Jean Chen Shih jeffrey Wang Center for Advancement of Drug Research and Evaluation College of Pharmacy Western University of Health Sciences Department of Pharmaceutical Sciences College of Pharmacy Marshall B.Ketchum University Department of Pharmacology and Pharmaceutical Sciences School of Pharmacy Department of Cell and Neurobiology Keck School of Medicine USC-Taiwan Center for Translational Research University of Southern California Department of Pharmaceutical Sciences College of Pharmacy Western University of Health Sciences

A high-performance liquid chromatography-electrospray ionization tandem mass spectrometric （HPLC- ESI-MS/MS） method was developed for the quantification of MHl148-clorgyline amide （NMl-amide）, a novel tumor-targeting monoamine oxidase A inhibitor, in mouse plasma. The method was validated in terms of sensitivity, precision, accuracy, recovery and stability and then applied to a pharmacokinetic study of NMl-amide in mice following intravenous administration. NMl-amide together with the internal standard （IS）, MHI-148, was extracted by protein precipitation using acetonitrile. Multiple reaction monitoring was used for quantification of NMl-amide by detecting m/z transition of 491.2-361.9, and 685.3-258.2 for NMl-amide and the IS, respectively. The lower limit of quantification （LLOQ） of the HPLC- MS/MS method for NMl-amide was 0.005 μg/mL and the linear calibration curve was acquired with R2〉 0.99 in the concentration range of 0.005-2μg/mL. The intra- and inter-day precisions of the assay were assessed by percentage of the coefficient of variations, which was within 9.8% at LLOQ and 14.0% for other quality control samples, whereas the mean accuracy ranged from 86.8% to 113.2%. The samples were stable under storage and experimental conditions. This method was successfully applied to a pharmacokinetic study in mice following intravenous administration of 5 mg/kg NMl-amide.

关键词： MH1148-clorgyline HPLC Mass spectrometry Pharmacokinetics

Significance of glacio-morphological factors in glacier retreat：a case study of part of Chenab basin,Himalaya

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Journal of Mountain Science 2017年第1期14卷 128-141页

作者： Rupal M.bRAHMbHATT I.M.bAHUGUNA b.P RATHORE Anil V.KULKARNI Rajesh D.SHAH A.S.RAJAWAT jeffrey S.KARGEL M.G. Science Institute Ahmedabad - 380009 India Space Applications Centre ISRO Ahmedabad - 380015 India Indian Institute of Science Bangalore-560012 India Department of Hydrology & Water Resources University of Arizona Tucson AZ USA

A study has been carried out in part of Chenab basin,Himalaya to understand the relationship between glacio-morphological factors and change in glacial area. Initially change in areal extent of glaciers was derived for two time frames(1962-2001/02 and 2001/02-2010/11). The study comprised of 324 glaciers for the monitoring period of 1962-2001/02 for,which 11% loss in glacial area was observed. Two hundred and thirty-eight glaciers were further monitored between 2001/02 and 2010/11. These glaciers showed an area loss of 1.1%. The annual deglaciation has been found to be higher during the period of 1962-2001/02 compared to 2001/02-2010/11. The spatial and temporal variability in deglaciation was also addressed usingglacio-morphic parameters. Area,length,percentage of debris cover,and various elevation parameters of glaciers were observed to have significant controls on relationships to the rate of glacial shrinkage. Largerarea and longer glaciers show a lower percentage of retreat than smaller and shorter ones. Moreover,glaciers located at lower altitudes and having gentle slopes show more area retreat. The results of area retreat in debris covered and debris free glaciers supports that the glaciers covered by debris retard ice melting at some extent. 158 glaciers were observed having no debris cover,and these exhibit 14% of loss in surface area. In glaciers having 40% debris cover,8% of deglaciation was observed. The glaciers located below equilibrium line altitude(ELA) have experienced 4.6% of deglaciation for the time frame 2001/02 – 2010/11 whereas it was found to be 1.1% for the glaciers occurring above ELA. However,theorientation of glaciers did not show any considerable influence on glacial change based on hypothesis.

关键词： Glacier retreat Aspect Slope Altitude Debris cover Areal extent Climate change

Continental-scale assessment of provisioning soil functions in Europe

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Ecological Processes 2013年第1期2卷 350-367页

作者： Gergely Tóth Ciro Gardi Katalin bódis Éva Ivits Ece Aksoy Arwyn Jones Simon jeffrey Thorum Petursdottir Luca Montanarella Institute for Environment and Sustainability Via Fermi Joint Research Centre Institute for Environment and SustainabilityVia Fermi 2749 TP280Ispra 21027Italy

Introduction:A framework is developed to link major soil functions to ecosystem services *** soil functions—with primary linkages to ecosystem services—are evaluated on a continental scale in ***:We defined major provisioning soil functions combining the approaches proposed by the Millennium Ecosystem Assessment and the Thematic Strategy for Soil Protection of the European *** productivity was evaluated by three main land use types(cropland,grassland,forest)using a validated expert model called *** include soil,climate and topographic *** material provision capacity of soils was assessed on the basis of(i)organic carbon content and(ii)availability of soil materials for ***:A coherent system of soil function-based ecosystem services was compiled,taking into account major soil *** also produced new data on soil-based provisioning ecosystem services,including productivity and raw material *** attempts to cover the main human activities requiring materials of soil origin and to map the locations where those materials are available on a continental scale provide new insight to this field of ***:Soil-based ecosystem services can be assessed by the evaluation of soil functions which play a role in the production of these *** analysis and comparison of the spatial distribution of the investigated soil functions were *** crop productivity showed a general trend to increase in a northward and westward direction,local soil quality in most regions—except in the Mediterranean—can compensate for climatic handicaps to a great *** of areas with potential for providing ecosystem services by individual soil functions highlights the complexity of decision-making for resource utilization but also the possibilities for optimization and more conscious management.

关键词： Soil ecosystem services Provisioning functions Soil productivity Soil quality Land evaluation

Changes in skin levels of two neutotrophins (glial cell line derived neurotrohic factor and neurotrophin-3) cause alterations in cutaneous neuron responses to mechanical stimuli

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生理学报 2008年第5期60卷 584-596页

作者： jeffrey Lawson Sabrina L. Mcllwrath H. Richard Koerber Department of Neurobiology University of Pittsburgh School of Medicine Pittsburgh PA 15261 USA

Neurotrophins are important for the development and maintenance of both high and low threshold mechanoreceptors(HTMRs and LTMRs).In this series of studies,the effects of constitutive overexpression of two different neurotrophins,neurotrophin-3(NT-3) and glial cell line derived neurotrohic factor(GDNF),were *** studies indicated that both of them may be implicated in the normal development of mouse dorsal root ganglion(DRG) *** from mice transgenically altered to overexpress NT-3 or GDNF(NT-3-OE or GDNF-OE mice) in the skin were examined using several physiological,immunohistochemi-cal and molecular *** vivo skin/nerve/DRG/spinal cord and skin/nerve preparations were used to determine the response characteristics of the cutaneous neurons;immunohistochemistry was used to examine the biochemical phenotype of DRG cells and the skin;RT-PCR was used to examine the levels of candidate ion channels in skin and DRG that may correlate with changes in physiological *** GDNF-OE mice,I-isolectin b4(Ib4)-immunopositive C-HTMRs(nociceptors),a large percentage of which are sensitive to GDNF,had significantly lower mechanical thresholds than wildtype(WT) *** thresholds for the same cells were not *** sensitivity changes in GDNF-OE mice were correlated with significant increases in acid sensing ion channels 2a(ASIC2a) and 2b(ASIC2b) and transient receptor potential channel A1(TRPA1),all of which are putative mechanosensitive ion *** of NT-3 affected the responses of A-LTMRs and A-HTMRs,but had no effect on *** adapting type 1(SA1) LTMRs and A-HTMRs had increased mechanical sensitivity compared to *** sensitivity was correlated with significant increases in acid-sensing ion channels ASIC1 and *** data indicates that both neurotrophins play roles in determining mechanical thresholds of cutaneous HTMRs and LTMRs and that sensitivity changes involve the ASIC family of pu

关键词：皮肤胶质细胞神经元反应机械性刺激

Toll-like receptor agonists shape the immune responses to a mannose receptor-targeted cancer vaccine

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Cellular & Molecular Immunology 2015年第6期12卷 719-728页

作者： Li-Zhen He jeffrey Weidlick Crystal Sisson Henry C Marsh Tibor Keler Celldex Therapeutics Inc. Hampton N J USA and Celldex Therapeutics Inc. Needham MA USA

Previous studies have documented that selective delivery of protein antigens to cells expressing mannose receptor （MR） can lead to enhanced immune responses. We postulated that agents that influenced the MR expression level, and the activation and migration status of MR-expressing antigen presenting cells, would modulate immune responses to MR-targeted vaccines. To address this question, we investigated the effect of clinically used adjuvants in human MR transgenic （hMR-Tg） mice immunized with an MR-targeting cancer vaccine composed of the human anti-MR monoclonal antibody b 11 fused with the oncofetal protein, human chorionic gonadotropin beta chain （hCGβ）, and referred to as b 11-hCGβ. We found that humoral responses to low doses of b11-hCGβ could be enhanced by prior administration of GM-CSF, which upregulated MR expression in vivo. However, co-administration of the Toll-like receptor （TLR） agonists, poly-ICLC and/or CpG with b11-hCGβ was required to elicit Thl immunity, as measured by antigen-specific T-cell production of IFN-γ. The TLR agonists were shown to increase the number of vaccine-containing cells in the draining lymph nodes of immunized hMR-Tg mice. In particular, with b11-hCGβand poly-ICLC, a dramatic increase in vaccine-positive cells was observed in the T-ceU areas of the lymph nodes, compared to the vaccine alone or combined with GM-CSF. Importantly, the absence of the TLR agonists during the priming immunization led to antigen-specific tolerance. Therefore, this study provides insight into the mechanisms by which adjuvants can augment immune responses to b11-hCGβ and have implications for the rationale design of clinical studies combining MR-targeted vaccination with TLR agonists.

关键词： GM-CSF hCGβ mannose receptor Toll-like receptor agonists

Liver biopsy in a district general hospital:Changes over two decades

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World Journal of Gastroenterology 2007年第40期13卷 5336-5342页

作者： Wing-Kin Syn Caroline bruckner-Holt Adam Farmer Sarah Howdle jeffrey bateman Liver and Hepatobiliary Unit Queen Elizabeth HospitalBirminghamB 15 2THUnited Kingdom Department of Gastroenterology Princess Royal HospitalTelfordUnited Kingdom Department of Gastroenterology City HospitalBirminghamUnited Kingdom Department of Radiology Princess Royal HospitalYelfordUnited Kingdom

AIM： To study liver biopsy practice over two decades in a district general hospital in the United Kingdom.METHODS： We identified all patients who had at least one liver biopsy between 1986 and 2006 from the databases of the radiology and gastroenterology departments. Subjects with incomplete clinical data were excluded from the study.RESULTS： A total of 103 liver biopsies were performed. Clinical data was available for 88 patients, with 95 biopsies. between 1986 and 1996, 18 （95%） out of the 19 liver biopsies performed were blind and 6 （33%） were for primary biliary cirrhosis. between 1996 and 2006, 14 （18%） out of 76 biopsies were blind; and the indications were abnormal liver tests （33%）, hepatitis C （12%） and targeted-biopsies （11%）. Liver biopsies were unhelpful in 5 （50） subjects. Pain was the most common complication of liver biopsy （5%）. No biopsy-related mortality was reported. There was a trend towards more technical failures and complications with the blind biopsy technique.CONCLUSION： Liver biopsies performed in small district hospitals are safe and useful for diagnostic and staging purposes. Abnormal liver tests, non-alcoholic fatty liver disease and targeted biopsies are increasingly common indications. Ultrasound-guided liver biopsies are now the preferred method and are associated with fewer complications.

关键词： Complication District general Indication Liver biopsy Non-alcoholic fatty liver