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An efficient method for mapping the 12c+12c molecular resonances at low energies

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Nuclear Science and Techniques 2019年第8期30卷 77-83页

作者： Xiao-Dong Tang Shao-Bo Ma Xiao Fang brian Bucher Adam Alongi craig cahillane Wan-Peng Tan Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China Idaho National Laboratory Idaho FallsID 83415USA Institute for Structure and Nuclear Astrophysics University of Notre DameNotre DameIN 46556USA 123

The 12c+12c fusion reaction is famous because of its complication of molecular resonances,and it plays an important role in both nuclear structural research and astrophysics. It is extremely difficult to measure the cross sections of 12c+12c fusions at energies of astrophysical relevance because of the very low reaction yields. To measure the complicated resonant structure that exists in this important reaction, an efficient thick target method has been developed and applied for the first time at energies Ec.m.can of the cross sections over a relatively wide range of energies can be carried out using only a single beam energy. The result of measurement at Ec.m.=4.1 MeV is compared with results from previous *** method will be useful for searching for potentially existing resonances of 12c+12c in the energy range 1 MeVc.m.<3 MeV.

关键词： 12c+12c Molecular resonance Thick targetmethod 12c(12c, p)^23Na

Genic c-Methylation in Soybean Is Associated with Gene Paralogs Relocated to Transposable Element-Rich Pericentromeres

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Molecular Plant 2018年第3期11卷 485-495页

作者： Moaine El Baidouri Kyung Do Kim brian Abernathy Ying-Hui Li Li-Juan Qiu Scott A. Jackson center for Applied Genetic Technologies University of Georgia 111 Riverbend Road Athens GA 30602 USA corporate R&D LG Chem LG Science Park 30 Magokjungang 10-ro Gangseo-gu Seoul 07796 Republic of Korea The National Key Facility for crop Gene Resources and Genetic Improvement (NFcRI) Institute of Crop Science Chinese Academy of Agricultural SciencesBeijing China These authors contributed equally to this article.

Most plants are polyploid due to whole-genome duplications （WGD） and can thus have duplicated genes. Following a WGD, paralogs are often fractionated （lost） and few duplicate pairs remain. Little attention has been paid to the role of DNA methylation in the functional divergence of paralogous genes. Using high- resolution methylation maps of accessions of domesticated and wild soybean, we show that in soybean, a recent paleopolyploid with many paralogs, DNA methylation likely contributed to the elimination of ge- netic redundancy of polyploidy-derived gene paralogs. Transcriptionally silenced paralogs exhibit partic- ular genomic features as they are often associated with proximal transposable elements （TEs） and are pref- erentially located in pericentromeres, likely due to gene movement during evolution. Additionally, we provide evidence that gene methylation associated with proximal TEs is implicated in the divergence of expression profiles between orthologous genes of wild and domesticated soybean, and within populations.

关键词： soybean paralog gene methylation proximal transposable element methylation spreading

cardiac tamponade due to group a streptococcal pericarditis in a 10-month-old boy and a review of the literature

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Open Journal of Pediatrics 2011年第4期1卷 87-89页

作者： Matthew c. Schwartz Matthew J. Gillespie Paul Stephens brian Fisher 不详

Group A streptococcus (GAS) is a rare cause of purulent pericarditis in pediatric patients as only 7 cases have been reported. we present a 10-month-old boy who developed cardiac tamponade from GAS and was successfull... 详细信息

关键词： Streptococcus Pericarditis Pericardiocentesis Tamponade

Materials Development

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基础教育外语教学研究 2005年第8期 37-40页

作者： brian Tomlinson

Introduction Materials development is both a field of study and apracticalun *** a field it studies the principles and procedures of the design,implement ation and evaluation and adaptationo flanguage teaching materials,

关键词：中小学英语教学课程改革教学资源

Evidence of proteins, chromosomes and chemical markers of DNA in exceptionally preserved dinosaur cartilage

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National Science Review 2020年第4期7卷 815-822页

作者： Alida M.Bailleul wenxia Zheng John R.Horner brian K.Hall casey M.Holliday Mary H.Schweitzer Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences cAS center for Excellence in Life and Paleoenvironment Department of Biological Sciences North Carolina State University Department of Geology University of Lund Honors Program Chapman University Department of Pathology and Anatomical Sciences University of Missouri North carolina Museum of Natural Sciences Department of Biology Dalhousie University

A histological ground-section from a duck-billed dinosaur nestling(Hypacrosaurus stebingeri) revealed microstructures morphologically consistent with nuclei and chromosomes in cells within calcified *** hypothesized that this exceptional cellular preservation extended to the molecular level and had molecular features in common with extant avian cartilage. Histochemical and immunological evidence supports in situ preservation of extracellular matrix components found in extant cartilage, including glycosaminoglycans and collagen type II. Furthermore, isolated Hypacrosaurus chondrocytes react positively with two DNA intercalating stains. Specific DNA staining is only observed inside the isolated cells, suggesting endogenous nuclear material survived fossilization. Our data support the hypothesis that calcified cartilage is preserved at the molecular level in this Mesozoic material, and suggest that remnants of once-living chondrocytes, including their DNA, may preserve for millions of years.

关键词： cartilage dinosaur nuclei chromosomes collagen Ⅱ DNA markers

Whole-body heat exposure induces membrane changes in spermatozoa from the cauda epididymidis of laboratory mice

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Asian Journal of Andrology 2010年第4期12卷 591-598页

作者： Harsha wechalekar brian P. Setchell Eleanor J. Peirce Mario Ricci chris Leigh William G. Breed Discipline of Anatomy and Pathology School of Medical Sciences Faculty of Health Sciences University of Adelaide Adelaide South Australia 5005 Australia Division of Health Sciences University of South Australia City East Campus Adelaide South Australia 5000 Australia

This study was carried out to determine if exposure to hot environmental temperatures had a direct, detrimental effect on sperm quality. For this the effect of whole-body heat exposure on epididymal spermatozoa of laboratory mice was investigated. c57BL/6 mice （n = 7） were housed in a microclimate chamber at 37℃-38℃ for 8 h per day for three consecutive days, while control mice （n = 7） were kept at 23℃-24℃. cauda epididymal spermatozoa were obtained 16 h after the last heat treatment. The results showed that sperm numbers were similar in the two groups （P = 0.23）, but after heat treatment, a significant reduction in the percentage of motile sperm was present （P 〈 0.0001）. Membrane changes of the spermatozoa were investigated by staining with phycoerythrin （PE）- conjugated Annexin V, which detects exteriorization of phosphotidylserine from the inner to the outer leaflet of the sperm plasma membrane, and 7-aminoactinomycin D （7-AAD）, which binds to the sperm nucleus when the plasma membrane is damaged. The percentage of spermatozoa showing positive staining with Annexin V-PE or 7-AAD or both, was significantly higher （P 〈 0.05） in heat-exposed mice compared with controls. These results show that whole-body heat exposure to 37℃-38℃ induces membrane changes in the epididymal spermatozoa of mice, which may lead to apoptosis.

关键词： laboratory mice sperm membrane damage whole-body heat

SImmetry<sup>&reg</sup>Sacroiliac Joint Fusion System with SImmetry Decorticator<sup>&reg</sup>

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Surgical Science 2015年第7期6卷 282-291页

作者： brian Beaubien Richard M. Salib Louis c. Fielding Jon E. Block Zyga Technology Inc. Minnetonka USA Institute for Low Back and neck care Minneapolis USA The Jon Block Group San Francisco USA

Low back pain (LBP) is one of the most prevalent, disabling and costly medical conditions affecting modern society. LBP presents a significant challenge to effective treatment due to often multifactorial or unknown etiology. Since the 1980s, the sacroiliac (SI) joint has become increasingly recognized as a common source of LBP. In contrast to other sources of LBP such as internal disc disruption and even psychosocial factors, SI joint pain and degeneration are reliably identified with provocative manual tests and diagnostic injections. Fusion of the SI joint has been shown to provide enduring symptom relief, and minimally invasive techniques developed over the past decade have further reduced the operative risks associated with open fusion surgery. Minimally invasive SI joint fusion surgeries are typically performed by placing rigid implant components across the joint space. The implants provide mechanical fixation while bony fusion develops. Decortication of the SI joint space during the procedure produces a bleeding bone surface that allows for increased availability of autologous mesenchymal stem cells and growth factors at the fusion site. coupled with the mechanical stability provided by the implant and autologous bone graft, decortication provides an optimal environment for bone growth and subsequent fusion of the joint. This report describes the background of SI joint disease, treatment, and the minimally invasive SImmetry? Sacroiliac Joint Fusion System (Zyga Technology, Inc., Minnetonka, MN, USA), with emphasis on the decortication instrumentation and procedure.

关键词： Sacroiliac Decortication Low Back Pain Minimally Invasive

Hypercoagulability in Liver Transplant Recipients: Does Portal Vein Thrombosis Predict Post-Operative Thrombotic complications?

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Open Journal of Organ Transplant Surgery 2011年第1期1卷 1-7页

作者： Brintha K. Enestvedt c. Kristian Enestvedt brian Diggs Susan L. Orloff 不详

Background: cirrhotic patients have higher rates of hypercoagulable disorders. we hypothesized that orthotopic liver transplant (OLT) recipients with pre-operative portal vein thrombosis (PVT) have more post-operative thrombotic events than those without PVT. Aims: To compare rates of post-op thrombotic events and outcomes between those with and without pre-op PVT. Methods: All OLT recipients between 1/02-4/09 were retrospectively reviewed. Outcome measures included survival, deep venous thrombosis, pulmonary embolism, hepatic artery thrombosis, and recurrent PVT. Minimum follow up was 6 months. Results: In 363 OLTs performed, mean recipient age was 53.1 yrs (±9.2);268 patients were male. Mean MELD at transplant was 22.1 (±6.2). The prevalence of pre-op PVT was 11.2% (41/350). There was no difference in the % of post-op thrombotic events between those with and without PVT (p = 0.77). MELD, recipient and donor age, and gender were similar in both groups. Mean survival in those with pre-op PVT was 85.2 months vs. 78.7 in those without PVT (p = 0.19). conclusions: The rate of post-op thrombotic events was equivalent in OLT recipients with and without pre-op PVT. The presence of PVT did not adversely impact patient survival and should not be a contraindication to OLT.

关键词： Portal Vein Thrombosis Orthotopic Liver Transplantation Hypercoagulability Thromboses

Ammonia Emissions in Europemcosts, Regulation and Targets with Focus on Denmark

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Journal of Agricultural Science and Technology(A) 2012年第3期2卷 285-293页

作者： brian H Jacobsen Institute of Food and Resource Economics Faculty of Life Sciences University of Copenhagen Frederiksberg C. 1958 Denmark

The nec （National Emission ceiling） directive has set targets for the 2010 ammonia emissions from a number of European countries. The target will be reached by most EU-countries and the total emission for EU-27 has been reduced by 22% from 1990 to 2007. Denmark is one of the countries with the largest reductions since 1990 and the article aims at the measures and costs involved. The conclusion is that the costs have been under 3ε per kg NH3-N. Measures in several countries are under 5ε per kg NH3-N, which is a likely minimum for the benefits of reducing NH3-N. The findings suggest that the same measures might be cheaper in the netherlands and Denmark than in the UK and the USA due to technology advances and stricter regulations in the past. The new Danish application procedure, when increasing the animal production, has tried to make the acceptance procedure quicker and dynamic ensuring that new technology is adopted quicker and that the farm has the right location. It is concluded that the new application process so far has not lived up to the high expectations at the outset. Despite this, the paper concludes that Denmark is likely to reduce emission by 50% from 1990 to 2020 and reach the likely 2020 nec ceiling.

关键词： Ammonia emission costs cost effective measores nec directive and regulation.