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Modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies

Research in Astronomy and Astrophysics 2011年第12期11卷 1429-1448页

作者： james Q.Feng c.F.Gallo Superconix inc 2440 Lisbon AvenueLake ElmoMN 55042USA

We present an efficient, robust computational method for modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies. With appropriate mathematical treatments, the apparent numerical difficulties associated with singularities in computing elliptic integrals are completely removed. Using a boundary element discretization procedure, the governing equations are transformed into a linear algebra matrix equation that can be solved by straightforward Gauss elimination in one step without further iterations. The numerical code implemented according to our algorithm can accurately determine the surface mass density distribution in a disk galaxy from a measured rotation curve （or vice versa）. For a disk galaxy with a typical flat rotation curve, our modeling results show that the surface mass density monotonically decreases from the galactic center toward the periphery, according to Newtonian dynamics. in a large portion of the galaxy, the surface mass density follows an approximately exponential law of decay with respect to the galactic radial coordinate. Yet the radial scale length for the surface mass density seems to be generally larger than that of the measured brightness distribution, suggesting an increasing mass-tolight ratio with the radial distance in a disk galaxy. in a nondimensionalized form, our mathematical system contains a dimensionless parameter which we call the ＂galactic rotation number＂ that represents the gross ratio of centrifugal force and gravitational force. The value of this galactic rotation number is determined as part of the numerial solution. Through a systematic computational analysis, we have illustrated that the galactic rotation number remains within 4-10% of 1.70 for a wide variety of rotation curves. This implies that the total mass in a disk galaxy is proportional to V02 Rg, with V0 denoting the characteristic rotation velocity （such as the ＂flat＂ value in a typical ro- tation curve） and Rg the radius of the galacti

关键词： galaxy: disk -- galaxies: general -- galaxies: kinematics and dynamics -- galaxies: structure -- methods: numerical and analytical

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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

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Selective toxicity of hydroxyl-rich carbon nanodots for cancer research

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Nano Research 2018年第4期11卷 2204-2216页

作者： Tak H. Kim Joseph P. Sirdaarta Qian Zhang Ehsan Eftekhari james St. John Derek kennedy ian E. cock Qin Li Queensland Micro and Nano Technology center & School of Engineering Griffith University 170 Kessels Rd Nathan OLD 4111 Australia Australian Rivers institute & School of Natural Sciences Griffith University 170 Kessels Rd Nathan QLD 4111 Australia Griffith institute for Drug Discovery Gfiffith University 46 Don Young Rd Nathan QLD 4111 Australia Menzies Health institute Queensland Griffith University Parkland Drive Southport QLD 4222 Australia

The toxicity of nanoparticles in a biological system is an integration of effects arising from surface functionali~ particle size, ionic dissolution, etc. This complexity suggests that generalization of a material＇s toxicity may be inappropriate. Moreover, from a medicinal point of view, toxicity can be used for treatment of malignant cells, such as cancer. in this stud~ highly biocompatible carbon nanodots （gcDs） were synthesized by reacting citric acid and urea in glycerol, which resulted in abundant hydroxyl functional groups on the particle surface. gcDs show excitation-dependent photoluminescence but with bright green to yellow emission. importantly, a series of toxicity assessments showed that as-synthesized gcDs possessed exceptional biocompatibilities to various biological entities including 18 bacteria species, Petunia axillaris seedlings, and Artemia franciscana nauplii. Furthermore, the particles were shown to have low to no toxic effects on human embryonic kidney （HEK-293）, breast （McF-7）, and oral squamous （cAL-27） carcinoma cell lines. Of particular interest, the gcDs displayed antiproliferative activities against ovarian choriocarcinoma cells （JAr/Jeg-3 cell lines）, which may be further explored for cancer drug discovery.

关键词： carbon nanodots nanotoxicity fluorescence choriocarcinoma cells thioredoxin reductase

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Alterations in gastric mucin synthesis by Helicobacter pylori

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World Journal of Gastroenterology 2000年第4期6卷 475-482页

作者： james c. Byrd Robert S. Bresalier Gastrointestinal cancer Research Laboratory Henry Ford Health Sciences CenterDetroitMIUSA Gastrointestinal cancer Research Laboratory Henry Ford Health Sciences CenterDetroitMIUSA Department of MedicineUniversity of Michigan School of MedicineAnn ArborMIUSA

iNTRODUcTiONHelicobacter pylori is recognized as a cause of chronicactive gastritis,gastric and duodenal ulcers,and gastriccancer,though the mechanisms of pathogenesis for ***-associated diseases are not yet well *** ... 详细信息

关键词： gastric mucin Helicobacter pylori

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Special issue on “Fluorescent probes”

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Frontiers of chemical Science and Engineering 2020年第1期14卷 1-3页

作者： Adam c.Sedgwick Tony D.james Department of chemistry University of Texas at AustinAustinTX 78712-1224USA Department of chemistry University of BathBathBA27AYUK

Fluorescent probes are intelligently designed molecules that transform the act of binding/reacting with a target analyte into an optical signal[1,2].Their high sensitivity and specificity coupled with high spatial and temporal resolution offers a non-invasive approach to observe a specific analyte within complex biological environments in real time with high precision[3].These"molecular tools"have the capability to interrogate the role of specific biomarkers that are associated with a particular disease state or can be used to improve our understanding of the role or certain species in a biological pathway[4,5].

关键词： Fluorescent specific reacting

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Outcomes following minimally invasive dorsal cheilectomy for hallux rigidus:A systematic review

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World Journal of Orthopedics 2024年第6期15卷 585-592页

作者： Katherine Esser james J Butler Mackenzie Roof Nathaniel P Mercer Michael c Harrington Alan P Samsonov Andrew J Rosenbaum John G kennedy Department of Orthopaedic Surgery University of Toledo Medical center University of Toledo College of Medicine and Life SciencesToledoOH 43614United States Department of Orthopedic Surgery NYU Langone HealthNew YorkNY 10002United States Department of Orthopedic Surgery Albany Medical CenterAlbanyNY 12208United States

BAcKGROUND cheilectomy of the 1^(st)metatarsophalangeal joint(MTPJ)is one of the most common procedures for the management of hallux ***,there is no consensus regarding outcomes following minimally invasive dorsal cheilectomy(MiDc)for the management of hallux *** To evaluate outcomes following MiDc for the management of hallux *** During November 2023,the PubMed,EMBASE and cochrane Library databases were systematically reviewed to identify clinical studies examining outcomes following MiDc for the management of hallux *** Six studies were *** total,348 patients(370 feet)underwent MiDc for hallux rigidus at a weighted mean follow-up of 37.9±16.5 *** distribution of patients by coughlin and Shurna's classification was recorded in 4 studies as follows:Ⅰ(58 patients,27.1%),Ⅱ(112 patients,52.3%),Ⅲ(44 patients,20.6%).Three studies performed an additional 1^(st)MTPJ arthroscopy and debridement following *** intra-articular bone debris was observed in 100%of patients in 1 *** weighted mean American orthopedic foot and ankle society score improved from a preoperative score of 68.9±3.2 to a postoperative score of *** complication rate was 8.4%,the most common of which was persistent joint pain and ***-two failures(8.7%)were ***-three secondary procedures(8.9%)were performed at a weighted mean time of 8.6±3.2 months following the index *** This systematic review demonstrated improvements in subjective clinical outcomes together with a moderate complication rate following MiDc for the management of hallux rigidus at short-term follow-up.A moderate reoperation rate at short-term follow-up was *** marked heterogeneity between included studies and paucity of high quality comparative studies limits the generation of any robust conclusions.

关键词： Minimally invasive dorsal cheilectomy Hallux rigidus The first metatarsophalangeal joint cheilectomy Minimally invasive surgery

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Vertebrate pesticide risk assessment by indigenous communities in New Zealand

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integrative Zoology 2010年第1期5卷 37-43页

作者： Shaun c.OGiLViE james M.ATARiA james WAiWAi james DOHERTY Aroha MiLLER james G.ROSS charles T.EASON Ecology Department Lincoln UniversityLincolnCanterburyNew Zealand Landcare Research LincolnCanterburyNew Zealand Lake Waikaremoana Hapu Restoration Trust TuaiNew Zealand Tuhoe Tuawhenua Trust MuruparaNew Zealand

in New Zealand,the vertebrate pesticide sodium fluoroacetate(compound 1080)is aerially applied in baits for control of the brush-tailed possum Trichosurus vulpecula(Kerr,1792).Maori,the indigenous people of New Zealand,have raised concerns about 1080 impacts on culturally-important ***,we outline two steps taken to help Maori assess 1080 ***,field research was undertaken to determine if naturally-occurring plants utilized by a Maori community for food and medicine would take up 1080 from *** baits were placed at the base of individual plants of two species,pikopiko(Asplenium bulbiferum)and karamuramu(coprosma robusta).Plants were sampled at various times up to 56 days,and samples were analyzed for 1080 *** 1080 was detected in any of the pikopiko samples,whereas 1080 was detected in karamuramu,at a maximum concentration of 5 ppb after seven days,and 2.5 ppb after 14 *** concentration decreased to 0 at 28 days,indicating that 1080 was not *** results of the present study suggest there is negligible risk of humans being poisoned by consum-ing plants that have taken up 1080 from *** allay community concerns that minute concentrations of 1080 might influence the medicinal properties of plants,it is suggested that a withholding period of 30 days after 1080 control operations could be ***,after further consultation we undertook a review of the scientific literature relating to 1080 impacts on additional non-target species of cultural importance to *** information was presented on an interactive foodweb database that allowed the collection and presentation of a large volume of complex information about 1080 in a holistic and pictorial *** database was presented to many Maori communities throughout New Zealand,and feedback was overwhelmingly *** database is likely to play a key role in informing these communities about 1080,and is seen as an important new tool to help these communities

关键词： 1080 indigenous communities Maori risk assessment sodium fluoroacetate

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Harnessing the Potential of the Tea Tree Genome

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Molecular Plant 2017年第6期10卷 788-790页

作者： Xianjun Lai james c. Schnable Department of Agronomy and Horticulture Center for Plant Science Innovation University of Nebraska-Lincoln Lincoln 68588 USA Maize Research institute Sichuan Agricultural University Chengdu 611130 China

Tea is arguably the most popular non-alcoholic beverage in the world. The primary source of tea is the boiled leaves of the plant camellia sinensis. Agronomic production of tea leaves currently depends heavily on a relatively small number of vegetatively propagated clonal varieties of c. sinensis. However, there is an urgent need for new cultivars, but conventional approaches to breeding can take 22-25 years to produce a new desirable c. sinensis accession （as reviewed by chert et al., 2007）.

关键词： Harnessing Tea Tree Genome metabolites and downregulation

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colonoscopy quality with Entonox? vs intravenous conscious sedation:18608 colonoscopy retrospective study

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World Journal of Gastrointestinal Endoscopy 2017年第9期9卷 471-479页

作者： Alexander R Robertson Nicholas A kennedy james A Robertson Nicholas i church colin L Noble Department of Gastroenterology Western General Hospital centre for Genomic and Experimental Medicine University of Edinburgh Department of Gastroenterology University of Exeter School of Life Sciences University of Nottingham Royal infirmary of Edinburgh

AiM To compare colonoscopy quality with nitrous oxide gas(Entonox?) against intravenous conscious sedation using midazolam plus *** A retrospective analysis was performed on a prospectively held database of 18608 colonoscopies carried out in Lothian health board hospitals between July 2013 and January *** quality of colonoscopies performed with Entonox was compared to intravenous conscious sedation(abbreviated in this article as iVM).Furthermore,the quality of colonoscopies performed with an unmedicated group was compared to *** study used the following key markers of colonoscopy quality:(1) patient comfort scores;(2) caecal intubation rates(ciRs); and (3) polyp detection rates (PDRs).We used binary logistic regression to model the *** There was no difference in the rate of moderate-toextreme discomfort between the Entonox and iVM groups (17.9% vs 18.8%; OR = 1.06,95%ci: 0.95-1.18,P = 0.27).Patients in the unmedicated group were less likely to experience moderate-to-extreme discomfort than those in the iVM group(11.4% vs 18.8%; OR = 0.71,95%ci: 0.60-0.83,P ifference in caecal intubation between the Entonox and iVM groups(94.4% vs 93.7%; OR = 1.08,95%ci: 0.92-1.28,P = 0.34).There was no difference in caecal intubation between the unmedicated and iVM groups (94.2% vs 93.7%; OR = 0.98,95%ci: 0.79-1.22,P = 0.87).Polyp detection in the Entonox group was not different from iVM group (35.0% vs 33.1%; OR = 1.01,95%ci: 0.93-1.10,P = 0.79).Polyp detection in the unmedicated group was not significantly different from the iVM group (37.4% vs 33.1%; OR = 0.97,95%ci: 0.87-1.08,P = 0.60).cONcLUSiON The use of Entonox was not associated with lower colonoscopy quality when compared to intravenous conscious sedation using midazolam plus opioid.

关键词： Gastrointestinal endoscopy colonoscopy caecal intubation Benzodiazepine Polyp detection Nitrous oxide Entonox Midazolam Sedation Unsedated

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Alignment of the hindfoot following total knee arthroplasty: A systematic review

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World Journal of Orthopedics 2021年第10期12卷 791-801页

作者： james J Butler Nathaniel P Mercer Eoghan T Hurley Mohammad T Azam John G kennedy Department of Orthopedic Surgery Royal College Surgeons in IrelandDublin 18Ireland Department of Orthopedic Surgery NYU Langone HealthNew YorkNY 10002United States

BAcKGROUND There appears to be a close relationship between deformities at the knee joint and at the hindfoot in patients with knee osteoarthritis(OA).Despite this intrinsic link,there is a dearth of studies investigating alterations in hindfoot alignment following total knee arthroplasty(TKA)in patients with knee *** To evaluate changes in alignment of the hindfoot following TKA,foot and ankle clinical outcomes in terms of subjective clinical scoring tools following surgical intervention,and to analyse the level of evidence(LOE)and quality of evidence(QOE)of the included *** MEDLiNE,EMBASE and cochrane Library databases were systematically reviewed in accordance with the Preferred Reporting items for Systematic Reviews and Meta-Analyses *** reporting changes in the postoperative alignment of the hindfoot following TKA were *** level and QOE were recorded and *** Eleven studies with a total of 1142 patients(1358 knees)met the inclusion/exclusion *** studies were of LOE ii and 5 studies were of LOE *** with preoperative varus knee deformity and valgus hindfoot deformity demonstrated improvement in hindfoot alignment post *** with preoperative varus knee deformity and varus hindfoot deformity demonstrated no improvement in hindfoot alignment following *** different radiographic parameters were used to measure the alignment of the hindfoot across the included studies,with the tibio-calcaneal angle most frequently utilised(27.3%).cONcLUSiON This systematic review demonstrated that the hindfoot may display compensatory changes in alignment following TKA in patients with knee ***,the marked heterogeneity between the included studies and poor QOE limits any meaningful cross sectional comparisons between ***,well designed studies are necessary to determine the changes and outcomes of hindfoot alignment following TKA.

关键词： Total knee arthroplasty Hindfoot alignment Hindfoot Knee osteoarthritis Varus knee deformity Valgus hindfoot deformity

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