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Comparison of Nitric Oxide Concentrations in μs-and ns-Atmospheric Pressure Plasmas by UV Absorption Spectroscopy

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Plasma Science and Technology 2016年第4期18卷 406-411页

作者： F.PETERS J.hirschberg N.MERTENS S.WIENEKE W.VIOL HAWK University of Applied Sciences and Arts Von-Ossietzky-Straβe 9937085 Gottingen Germany Fraunhofer Application Center for Plasma and Photonics Fraunhofer Institute for Surface Engineering and Thin Films IST Von-Ossietzky-Stratte 100 37085 Gottingen Germany

In this paper,an absorption spectroscopy measurement method was applied on two atmospheric pressure plasma sources to determine their production of nitric *** concentrations are essential for evaluating the plasma sources based on the principle of the Dielectric Barrier Discharge（DBD）for applications in plasma *** described method is based on a setup with an electrodeless discharge lamp filled with a mixture of oxygen and *** of the emitted wavelengths is an important resonance wavelength of nitric oxide（λ = 226.2 nm）.By comparing the absorption behaviour at the minimum and maximum of the spectral absorption cross section of nitric oxide around that wavelength,and measuring the change in intensity by the absorbing plasma,the concentration of nitric oxide inside the plasma can be *** produced nitric oxide concentrations depend on the pulse duration and are in the range of 180 ppm to 1400 ppm,so that a distance of about 10 cm to the respiratory tract is enough to conform to the VDI Guideline 2310.

关键词： nitric oxide(NO)concentration dielectric barrier discharge(DBD) ultraviolet(UV)absorption spectroscopy plasma medicine pulse duration ns-source μs-source

Beating the blues:engineering cryptochrome expression improves soybean yield

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Molecular Plant 2021年第2期14卷 202-204页

作者： ronald Pierik Plant Ecophysiology Department of BiologyUtrecht UniversityPadualaan 83584 CH Utrechtthe Netherlands

Phytochrome A overexpression can increase harvest index,as was shown 25 years ago in a breakthrough paper on tobacco(Robson et al.,1996).The impact of this important discovery has,however,not been fully *** at high densities often respond strongly to nearby competitors by strong elongation of their internodes and upward bending of their leaves,i.e.,shade *** is crucial for plants to ascertain access to sunlight,and this navigation through vegetation occurs through light cues that are sensed with various photoreceptors.A spectacular sensitivity is displayed by sun-loving plants that can already sense their nearby competitors even before mutual shading occurs and respond through a first acceleration of shoot *** anticipatory response is triggered through red(R):far-red(FR)light-sensitive phytochrome photoreceptors that detect FR light that is reflected by nearby *** the vegetation continues to grow and true shading occurs,there is also a significant depletion of red and blue light,since the latter two are absorbed for photosynthesis in the overhead leaves(reviewed in Pierik and Ballaré,2021).Plants can respond to blue light depletion,especially when integrating it with signaling of FR enrichment in Arabidopsis(de Wit et al.,2016).

关键词： depletion soybean breakthrough

Geometric morphometric analysis of the early Pleistocene hominin teeth from Jianshi,Hubei Province,China

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Science China Earth Sciences 2010年第8期53卷 1141-1152页

作者： ronald CLARKE University of the Witwatersrand JohannesburgSouth Africa

Although the early Pleistocene hominin fossils found in East Asia continent are widely recognized as the earliest hominins migrated from Africa, debates remain on the morphology and taxonomy of these fossils. In this study, dental crown shape of the three early Pleistocene hominin teeth (P3, M1, and M1) found in Jianshi, Hubei Province of China was analyzed by means of geometric morphometrics. The comparative samples of fossil hominins from Africa, Asia, and Europe as well as those of modern humans (N=257) were used. The results indicate that the contour, asymmetry, and cusp patterns of these three types of teeth differ obviously between the fossil hominins and modern humans. The crown shape of P3 in most fossil hominins including Australopithecus, African early Homo, and Asian Pleistocene hominins are asymmetric with their crown occlusal contours long and curving elliptic-shaped. The occlusal contour of the fossil hominin M1 is symmetric and rectangle-shaped with no marked cusp protrusion. The crown shape of fossil M1 is characterized by asymmetric contour with slightly projected metaconid and hypoconid. On the contrary, in modern Chinese and some European late Pleistocene hominins, the crowns of P3s show symmetric contours with buccal side wider than lingual side; the crown shape of M1 is asymmetric with lingual cusp distalplaced, especially for hypoconid; the M1 has symmetric and round crown contour. Our study reveals that Australopithecus has wide variations in its crown shape, whereas these dental morphospaces of Asian hominins are closely placed. The crown contour, symmetry, and cusp patterns of these three teeth of Jianshi hominin resemble those of Asian early and middle Pleistocene hominins. No marked difference in dental crown shape is shown between the Jianshi hominin and other Chinese Homo erectus, and there is also no evidence in support of the Jianshi hominin's closeness to Australopithecus and African early Homo members.

关键词： human evolution tooth shape geometric morphometric Jianshi Hubei China

Chemokine signaling involving chemokine (C-C motif) ligand 2 plays a role in descending pain facilitation

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Neuroscience Bulletin 2012年第2期28卷 193-207页

作者： ronald Dubner Department of Neural and Pain Sciences School of Dentistry & Program in Neuroscience University of Maryland

Objective Despite accumulating evidence on a role of immune cells and their associated chemicals in mecha- nisms of pain, few studies have addressed the potential role of chemokines in the descending facilitation of persistent pain. The present study was undertaken to test the hypothesis that the chemokine （C-C motif） ligand 2 （CCL2）（commonly known as monocyte chemoattractant protein-1） signaling in the rostral ventromedial medulla （RVM）, a pivotal structure in brainstem pain modulatory circuitry, is involved in descending pain facilitation in rats. Methods An L5 spinal nerve ligation （SNL） was produced in rats under pentobarbital anesthesia. Western blot and immunohistochemistry were used to detect the expression levels of CCL2 and CCL2 receptor （CCR2）, and examine their distributions compared with the neuronal marker NeuN as well as glial markers glial fibrillary acidic protein （GFAP, astroglial） and CD 11 b （microglial）, respectively. Results SNL induced an increase in CCL2 expression in the RVM, and this returned to the control level at 4 weeks after injury. The induced CCL2 colocalized with NeuN, but not with GFAP and CD1 lb. CCR2 was also upregu- lated by SNL in the RVM, and this increase lasted for at least 4 weeks. CCR2 was colocalized with CD1 lb but not GFAP. Few RVM neurons also exhibited CCR2 staining. Neutralizing CCL2 with an anti-CCL2 antibody （0.2-20 ng） or injecting RS-102895 （0.1-10 pmol）, a CCR2b chemokine receptor antagonist, into the RVM on day 1 after SNL, significantly at- tenuated the established thermal and mechanical hypersensitivity. In addition, injection of recombinant rat CCL2 （0.03-3 pmol） into the RVM induced dose-dependent hyperalgesia, which was prevented by pretreatment with RS-102895 （10 pmol）. Interleukin-β （IL-1]3）, a potent inducer of neuronal CCL2, was also selectively upregulated in RVM reactive as- trocytes. Injection of IL-1 ]3 （120 fmol） into the RVM induced behavioral hyperalgesia, which was blocked by RS-102895 （10 pmol

关键词： monocyte chemoattractant protein-l chemokine (C-C motif) receptor 2 rostral ventromedial medulla neu-ron-glial interaction neuropathic pain rat

Artificial enzymes,cancer chemotherapy,conjugation and nanoelectronics,and prebiotic chemistry

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Science China Chemistry 2011年第12期54卷 1803-1814页

作者： BRESLOW ronald Department of Chemistry Columbia University

This is a summary,with extensive references,of several areas of chemistry in which the Breslow lab has been involved,leading to work still underway in several of *** principal conclusions are described,but it will be ... 详细信息

关键词： artificial enzymes cancer chemotherapy conjugation and nanoelectronics prebiotic chemistry

Epidemiology of Sexual dysfunction in Asia compared to the rest of the world

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Asian Journal of Andrology 2011年第1期13卷 152-158页

作者： ronald W Lewis Section of Urology Medical College of Georgia Augusta GA 30912 USA

There have been a limited number of epidemiological studies published on sexual disorders in persons from Asia. This paper aims to assess the reports of sexual dysfunction epidemiological studies published in the English language that involved Asian countries. Key points are summarized in this paper from nine epidemiological papers on sexual dysfunction from Asia that were published in the English language. Seven met the criteria for evidence-based studies reaching a Prins score of at least 10 or more. Papers included in this report came from national and regional representative studies in peer review journals. These results for sexual dysfunction in the nine papers are summarized for various sexual dysfunctions in men and women in Asian countries. In three of these, worldwide data were presented in the same paper allowing comparisons with Asian data on prevalence rates. Detailed descriptions from each of these studies are presented in paragraph form. More detailed data on erectile dysfunction （ED） is presented in a tabular form. Collectively, there seems to be a need for country- and population-specific further descriptive and analytical epidemiological studies in all of the sexual disorders from Asia. This critical review paper should help guide these studies for reachinj[ evidence-based literature standards.

关键词： descriptive epidemiology male and female dysfunction male ED premature ejaculation

Isolation and Characterization of SARS-CoV-2 in Kenya

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American Journal of Molecular Biology 2024年第2期14卷 66-83页

作者： Albina Makio Robinson Mugasiali Irekwa Matthew Mutinda Munyao Caroline Wangui Njoroge Peter Kipkemboi Rotich Tonny Teya Nyandwaro Joanne Jepkemei Yego Anne Wanjiru Mwangi James Hungo Kimotho ronald Tanui Vincent Rutto Samson Muuo Nzou Center for Traditional Medicine and Drug Research Kenya Medical Research Institute Nairobi Kenya Center for Microbiology Research Kenya Medical Research Institute Nairobi Kenya Production Department Kenya Medical Research Institute Nairobi Kenya Department of Biochemistry and Microbiology Rhodes University Grahamstown South Africa Center for Virus Research Kenya Medical Research Institute Nairobi Kenya

The discovery of Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) in Wuhan, Hubei province, China, in December 2019 raised global health warnings. Quickly, in 2020, the virus crossed borders and infected individuals across the world, evolving into the COVID-19 pandemic. Notably, early signs of the virus’s existence were observed in various countries before the initial outbreak in Wuhan. As of 12th of April, the respiratory disease had infected over 762 million people worldwide, with over 6.8 million deaths recorded. This has led scientists to focus their efforts on understanding the virus to develop effective means to diagnose, treat, prevent, and control this pandemic. One of the areas of focus is the isolation of this virus, which plays a crucial role in understanding the viral dynamics in the laboratory. In this study, we report the isolation and detection of locally circulating SARS-CoV-2 in Kenya. The isolates were cultured on Vero Cercopithecus cell line (CCL-81) cells, RNA extraction was conducted from the supernatants, and reverse transcriptase-polymerase chain reaction (RT-PCR). Genome sequencing was done to profile the strains phylogenetically and identify novel and previously reported mutations. Vero CCL-81 cells were able to support the growth of SARS-CoV-2 in vitro, and mutations were detected from the two isolates sequenced (001 and 002). Genome sequencing revealed the circulation of two isolates that share a close relationship with the Benin isolate with the D614G common mutation identified along the S protein. These virus isolates will be expanded and made available to the Kenya Ministry of Health and other research institutions to advance SARS-CoV-2 research in Kenya and the region.

关键词： SARS-CoV-2 COVID-19 Whole Genome Sequencing Phylogenetic Analysis Nucleotide Substitutions Amino Acid Changes

Dietary Diversity and Food Security Status among Cameroonian Adults Living in Semi-Urban Areas: A Cross-Sectional Study

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Food and Nutrition Sciences 2024年第7期15卷 548-564页

作者： Tonou Boris ronald Tchuente Pauline Vervaine Hagbe Eliane Flore Eyenga Kemadjou Ruth Edwige Dibacto Ngassa Dany Joël Ngoumen Fotso Janvier Aime Youovop Nguemto Roussel Guy Takuissu Judith Laure Ngondi Julius Enyong Oben Department of Biochemistry Faculty of Science University of Yaound 1 Yaound Cameroon Centre for Food Food Security and Nutrition Research Institute of Medical Research and Medicinal Plant Studies Yaound Cameroon Center of Nutrition and Functional Foods Yaound Cameroon

Introduction: Food security is one of the greatest challenges that most African countries face. It is a concept that considers not only food quantity but also food quality. The objective of this study was to describe dietary diversity and food security status at the individual level in Cameroonian populations. Methods: A total of 1180 men and women aged 20 and over and living in the West, North West, and Littoral regions of Cameroon were recruited. Data on dietary habits were collected through the frequency of consumption of various food groups. Dietary diversity was assessed using a 24-hour dietary recall. Food security status was determined by combining two indicators (food consumption score and individual food diversity score). Results: The mean dietary diversity score of the population was 3.53 ± 1.44, p Conclusion: The diet diversity of adults living in the West, North West, and Littoral regions of Cameroon is medium. Although half of the study population was food secure, there is a need to implement food security policies further to reduce food insecurity among the Cameroonian population.

关键词： Dietary Diversity Individual Food Security Littoral West North West Cameroon

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Big Earth Data 2018年第4期2卷 368-394页

作者： Wansub Kim Peter Burgherr Matteo Spada Peter Lustenberger Anna Kalinina Stefan hirschberg Future Resilient Systems(FRS) ETH ZurichSingapore-ETH Centre(SEC)Singapore Laboratory for Energy Systems Analysis(LEA) Paul Scherrer Institut(PSI)Villigen PSISwitzerland

The Energy-related Severe Accident Database(ENSAD)is the most authoritative resource for comparative risk analysis of accidents in the energy *** ENSAD contains comprehensive,worldwide data,it is a non-spatial database in Microsoft Access ***,spatial characteristics of the data cannot be fully utilised as well as analysed *** on these premises,a new web-based version of ENSAD with GIS-capabilities–named ENSAD v2.0–is designed and developed using state-of-the-art,open source *** ENSAD v2.0 consists of two main components,i.e.a spatial database and a responsive web *** the spatial database,the current accident data are georeferenced and migrated from Microsoft Access,using a tiered *** responsive web application can be accessed from desktops as well as mobile devices,and provides both a 2D and 3D mapping platform that is developed on cloud-based,serverless *** v2.0 also allows assigning different user roles with specific access rights,and a public version with advanced visualisation capabilities has also been ***,a case study was carried out using a spatial analysis to visualise the potential impact radius of a natural gas pipeline explosion and to assess its consequences in terms of economic damage and casualties.

关键词： Energy-related severe accident database webbased GIS resilience cloud computing risk assessment