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Journal of Environmental Sciences 2015年第1期27卷 159-167页

作者： Nicolás m.Peleato robert C.Andrews Department of Civil Engineering University of Toronto

This work investigated the application of several fluorescence excitation–emission matrix analysis methods as natural organic matter（NOm） indicators for use in predicting the formation of trihalomethanes（THms） and haloacetic acids（HAAs）. Waters from four different sources（two rivers and two lakes） were subjected to jar testing followed by 24 hr disinfection by-product formation tests using chlorine. NOm was quantified using three common measures： dissolved organic carbon, ultraviolet absorbance at 254 nm, and specific ultraviolet absorbance as well as by principal component analysis, peak picking,and parallel factor analysis of fluorescence spectra. Based on multi-linear modeling of THms and HAAs, principle component（PC） scores resulted in the lowest mean squared prediction error of cross-folded test sets（THms： 43.7（μg/L）^2, HAAs： 233.3（μg/L）^2）. Inclusion of principle components representative of protein-like material significantly decreased prediction error for both THms and HAAs. Parallel factor analysis did not identify a protein-like component and resulted in prediction errors similar to traditional NOm surrogates as well as fluorescence peak picking. These results support the value of fluorescence excitation–emission matrix–principal component analysis as a suitable NOm indicator in predicting the formation of THms and HAAs for the water sources studied.

关键词： Natural organic matter Fluorescence Principal component analysis PARAFAC Disinfection byproducts Drinking water

Identification of isopeptidase activity in the midgut of insects： Purification, properties and nutritional ecology of a Hofmannophila pseudospretella （Lepidoptera： Oecophoridae） larval enzyme

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Insect Science 2010年第4期17卷 325-334页

作者： robert m. Simpson John T. Christeller Plant and Food Research Institute Tennant Drive Palmerston North 4474 Private Bag 11 030 New Zealand

A γ-glutamyl transpeptidase （isopeptidase） has been purified 580-fold to homogeneity from the midgut of keratinophagous larvae of Hofmannophila pseudospretella. The enzyme is a single polypeptide of molecular mass 80 kDa. The enzyme was identified by its hydrolytic activity against the synthetic substrate, γ-glutamyl-AmC, its molecular mass and inhibition profile compared to other γ-glutamyl transpeptidases. The enzyme is low or absent from most other insect digestive systems apart from other keratinophagous lepidopteran larvae and predatory carabids. While isopepfide bonds are present in high levels of the proteins in the diet of keratinophages, their presence in the diet of predatory beetles has not been established.

关键词： γ-glutamyl transpeptidase Hofmannophila pseudospretella isopeptidase,keratinophagous nutritional ecology

Specifications of Targeting Heterochromatin modifications in Plants

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molecular Plant 2018年第3期11卷 381-387页

作者： Jered m. Wendte robert J. Schmitz Department of Genetics University of Georgia Athens GA 30602 USA

Plants encode a diverse repertoire of DNA methyltransferases that have specialized to target cytosines for methylation in specific sequence contexts. These include the de novo methyltransferase, DOmAINS REARRANGED mETHYLTRANSFERASE 2 （DRm2）, which methylates cytosines in all sequence contexts through an RNA-guided process, the CHROmOmETHYLASES （CmTs）, which methylate CHH and CHG cytosines （where H is A, T, or C）, and mETHYLTRANSFERASE 1 （mET1）, which maintains methylation of symmetrical CG contexts. In this review, we discuss the sequence specificities and targeting of each of these pathways. In particular, we highlight recent studies that indicate CmTs preferentially target CWG or CWA/CAW motifs （where W is A or T）, and discuss how self-reinforcing feedback loops between DNA methyltransferases and histone modifications characteristic of heterochromatin specify targeting. Finally, the initiating events that lead to gene body methylation are discussed as a model illustrating how interde- pendent targeting of different silencing pathways can potentiate the establishment of off-target epialleles.

关键词： heterochromatin DNA methylation gene body methylation epiallele DNA methyltransferase,chromomethylase

Evaluation of the Heat,Entropy,and Rotational Changes Produced by Gravitational Segregation during Core Formation

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Journal of Earth Science 2015年第1期26卷 124-133页

作者： Anne m.Hofmeister robert E.Criss Department of Earth and Planetary Sciences Washington University

Core formation by gravitational segregation allegedly released sufficient interior heat to melt the Earth. Analysis of the energetics, which compare gravitational potential energy （Ug） of a fictitious, homogeneous reference state to Earth＇s current layered configuration, needs updating to correct errors and omissions, and to accommodate recent findings：（1） An erroneous positive sign was used for Ug while maintaining the reference value of 0 at infinity, which results in an incorrect sign fur AUg, which is crucial in determining whether a process is endothermic or exothermic. （2） The value of Ug for Earth＇s initial state is uncertain. （3） Recent meteorite evidence indicates that core formation began before the Earth was full-sized, which severely limits AUg. （4） Inhomogeneous accretion additionally reduced AUg. （5） The potentially large effect of differential rotation between the core and the mantle was not accounted for. （6） Entropy changes associated with creating order were neglected. Accordingly, we revise values of Ug, evaluate uncertainties, and show that AUg was converted substantially to eonfigurational energy （TAS）. These considerations limit the large sources of primordial heat to impacts and radioactivity. Although these processes may play a role in core formation, their energies are independent of gravitational segregation, which produces order and rotational energy, not internal heat. Instead, gravitational segregation promotes planetary cooling mainly because it segregates lithophilic radioactive elements upward, increasing surface heat flux while shortening the distance over which radiogenic heat diffuses outwards.

关键词： core formation primordial heat configurational energy thermodynamics rotational energy.

The heterogeneity of store-operated calcium entry in melanoma

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Science China(Life Sciences) 2016年第8期59卷 764-769页

作者： robert Hooper m.Raza Zaidi Jonathan Soboloff Fels Institute for Cancer Research and molecular Biology Lewis Katz School of Medicine at Temple University Department of medical Genetics & molecular Biochemistry Lewis Katz School of Medicine at Temple University

Calcium is a key regulator of many physiological processes that are perturbed in cancer, such as migration, proliferation and apoptosis. The proteins STIm and Orai mediate store-operated calcium entry(SOCE), the main pathway for calcium entry in non-excitable cells. Changes in the expression and function of STIm and Orai have been found in a range of cancer types and thus implicated in disease progression. Here we discuss the role of STIm, Orai and the SOCE pathway in the progression of melanoma and explore how the heterogeneous nature of melanoma may explain the lack of consensus in the field regarding the role of SOCE in the progression of this disease.

关键词： melanoma STIm1 Orail metastasis

Diagnosis and management of testosterone deficiency

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Asian Journal of Andrology 2015年第2期17卷 177-186,I0006页

作者： James A mcBride Culley C Carson robert m Coward Department of Urology University of North Carolina School of Medicine NC USA.

Testosterone supplementation therapy （TST） use has dramatically increased over the past decade, due to the availability of newer agents, aggressive marketing, and an increasing incidence of testosterone deficiency （TD）. Despite the increase in TST, a degree of ambiguity remains as to the exact diagnostic criteria of TD, and administration and monitoring of TST. One explanation for this phenomenon is the complex role testosterone plays in multiple physiologic pathways. Numerous medical co-morbidities and medications can alter testosterone levels resulting in a wide range of nonspecific clinical signs and symptoms of TD. The diagnosis is also challenging due to the lack of a definitive serum total testosterone level that reliably correlates with symptoms. This observation is particularly true in the aging male and is exacerbated by inconsistencies between different laboratory assays. Several prominent medical societies have developed guideline statements to clarify the diagnosis, but they differ from each other and with expert opinion in several ways. Aside from diagnostic dilemmas, there are numerous subtle advantages and disadvantages of the various testosterone agents to appreciate. The available TST agents have changed significantly over the past decade similar to the trends in the diagnosis of TD. Therefore, as the usage of TST increases, clinicians will be challenged to maintain an up-to-date understanding of TD and TST. The purpose of this review is to provide a clear description of the current strategies for diagnosis and management of TD.

关键词： androgens erectile dysfunction hormones hypogonadism testosterone

Current taxane formulations and emerging cabazitaxel delivery systems

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Nano Research 2018年第10期11卷 5193-5218页

作者： Boyang Sun robert m. Straubinger Jonathan F. Lovell Department of Biomedical Engineering University at Buffalo State University of New York Buffalo NY 14260 USA Department of Chemical and Biological Engineering University at Buffalo State University of New York Buffalo NY 14260 USA Department of Pharmaceutical Sciences University at Buffalo State University of New York Buffalo NY 14214 USA

Cabazitaxel is a second-generation taxane with promising anti-tumor activity and is approved for treating hormone-refractory metastatic prostate cancer previously treated with docetaxel. Although first-generation taxanes （i.e. paclitaxel and docetaxel） have sparked broad interest in a variety of drug delivery vehicles, fewer have yet been developed for cabazitaxel. This review summarizes several clinical-stage approaches for taxane formulation and recent efforts to develop novel cabazitaxel delivery systems.

关键词： cabazitaxel Jevtana taxanes drug delivery systems nanocarriers

On-board measurement of emissions from liquefied petroleum gas,gasoline and diesel powered passenger cars in Algeria

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Journal of Environmental Sciences 2014年第8期26卷 1651-1659页

作者： Saadane Chikhi ménouèr Boughedaoui Rabah Kerbachi robert Joumard Department of Industrial Chemistry Faculty of TechnologyUniversity of Blida 1Route de SoumaaBlida 09000Algeria Environmental Science and Technology Laboratory National Polytechnic School of AlgiersAlgiers 16200Algeria Transport and Environment Laboratory IfsttarBronFrance

On-board measurements of unit emissions of CO,HC,NOx and CO2 were conducted on 17 private cars powered by different types of fuels including gasoline,dual gasoline–liquefied petroleum gas（LPG）,gasoline,and diesel. The tests performed revealed the effect of LPG injection technology on unit emissions and made it possible to compare the measured emissions to the European Artemis emission model. A sequential multipoint injection LPG kit with no catalyst installed was found to be the most efficient pollutant reduction device for all of the pollutants,with the exception of the NOx. Specific test results for a sub-group of LPG vehicles revealed that LPG-fueled engines with no catalyst cannot compete with catalyzed gasoline and diesel engines. Vehicle age does not appear to be a determining parameter with regard to vehicle pollutant emissions. A fuel switch to LPG offers many advantages as far as pollutant emissions are concerned,due to LPG＇s intrinsic ***,these advantages are being rapidly offset by the strong development of both gasoline and diesel engine technologies and catalyst converters. The LPG＇s performance on a chassis dynamometer under real driving conditions was better than expected. The enforcement of pollutant emission standards in developing countries is an important step towards introducing clean technology and reducing vehicle emissions.

关键词： Unit emission Pollutant Vehicle On-board measurement LPG Gasoline Diesel

Atom-referenced and stabilized soliton microcomb

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Science China(Physics,mechanics & Astronomy) 2024年第2期67卷 2-8页

作者： Rui Niu Shuai Wan Tian-Peng Hua Wei-Qiang Wang Zheng-Yu Wang Jin Li Zhu-Bo Wang ming Li Zhen Shen Yu robert Sun Shui-ming Hu Brent ELittle Sai Tak Chu Wei Zhao Guang-Can Guo Chang-Ling Zou Yun-Feng Xiao Wen-Fu Zhang Chun-Hua Dong State Key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China University of Chinese Academy of Sciences Beijing 100049China Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Department of Physics and materials Science City University of Hong KongHong Kong 999077China State Key Laboratory for mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China

For the applications of the frequency comb in microresonators,it is essential to obtain a fully frequency-stabilized microcomb laser *** this study,we present a system for generating a fully atom-referenced stabilized soliton *** pump light around 1560.48 nm is locked to an ultra-low-expansion(ULE)*** pump light is then frequency-doubled and referenced to the atomic transition *** repetition rate of the soliton microcomb is injection-locked to an atomic-clockstabilized radio frequency(RF)source,leading to mHz stabilization at 1 *** a result,all comb lines have been frequencystabilized based on the atomic reference and the ULE cavity,achieving a very high precision of approximately 18 Hz at 1 s,corresponding to the frequency stability of 9.5×10^(-14).Our approach provides a fully stabilized microcomb experiment scheme with no requirement of f-2f technique,which could be easily implemented and generalized to various photonic platforms,thus paving the way towards the ultraprecise optical sources for high precision spectroscopy.

关键词： microcavity frequency comb dissipative Kerr solitons fully stabilized microcomb

Storylines of family medicine Ⅵ:ways of being—in the office with patients

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Family medicine and Community Health 2024年第S3期12卷 52-60页

作者： William B Ventres Leslie A Stone Lisa A LaVallee David Loxterkamp Jonisha R Brown Dael m Waxman Peter S Dorward Jeanne Cawse-Lucas Larry B mauksch Autumn m Kieber-Emmons Benjamin F Crabtree William L miller Veronica m Brohm Timothy P Daaleman Kelly Bossenbroek Fedoriw Family and Preventive medicine University of Arkansas for Medical Sciences College of MedicineLittle RockArkansasUSA mAHEC Family medicine Residency Mountain Area Health Education CenterAshevilleNorth CarolinaUSA Bucksport Regional Health Center BucksportMaineUSA Family medicine Atrium HealthCharlotteNorth CarolinaUSA Southfield medical Practice EdinburghUK Family medicine University of Washington School of MedicineSeattleWashingtonUSA Family medicine Lehigh Valley Health NetworkAllentownPennsylvaniaUSA morsani College of medicine University of South FloridaTampaFloridaUSA Family medicine and Community Health Rutgers Robert Wood Johnson Medical SchoolPiscatawayNew JerseyUSA Cancer Institute of New Jersey New BrunswickNew JerseyUSA Family medicine UNC School of MedicineChapel HillNorth CarolinaUSA

Storylines of Family medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine,as interpreted by individual family physicians and medical educators in the USA and elsewhere around the ***‘Ⅵ:ways of being—in the office with patients’,authors address the following themes:‘Patient-centred care—cultivating deep listening skills’,‘Doctor as witness’,‘Words matter’,‘Understanding others—metaphor and its use in medicine’,‘Communicating with patients—making good use of time’,‘The patient-centred medical home—aspirations for the future’,‘Routine,ceremony or drama?’and‘The life course’.may readers better appreciate the nuances of patient care through these essays.

关键词： centre illustration dimensions