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Asian Journal of Andrology 2016年第2期18卷 269-275,J0006,J0007页

作者： Anand Shridharani Ryan C owen osama o Elkelany Edward D Kim Department of Urology University of Tennessee College of Medicine Chattanooga TN 37403 USA Division of Urology Department of Surgery University of Tennessee Graduate School of Medicine Knoxville TN 37920 USA.

Varicoceles are the most common correctable etiology of male factor infertility. However, the detection and management of varicoceles have not been standardized. This has led to decades of debate regarding the effect of varicocele on male infertility and subsequently whether repair leads to an improved fertility status. The current body of evidence investigating the role of varicocele and varicocelectomy is weak and conflicting. The stance taken by the AUA and ASRM suggests that there is insufficient outcomes data to support evidenced-based guidelines, citing evidence used to provide current recommendations are generally of a low quality level. on the other hand, the EAU Guidelines give a level la of evidence for management of varicoceles that are clinically palpable, associated with subnormal semen analyses and having otherwise unexplained fertility. Besides aiding with clinical varicocele detection and management, clinical practice opinion statements and guidelines aim to direct and strengthen the infrastructure of future studies. We review the current status of opinion statements and guidelines in varicocele and management detection with focus on their application in practice.

关键词： guidelines varicocele varicocele detection varicocele management varicocelectomy

Modelling internal air systems ingas turbine engines

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航空动力学报 2007年第4期22卷 505-520页

作者： J Michael owen Department of Mechanical Engineering University of Bath

Rotating-disc systems can be used to model,experimentally and computationally,the flow and heat transfer that occur inside the internal cooling-air systems of gas turbine *** rotating-disc systems have been used successfully to simplify and understand some of the complex flows that occur in internal-air systems,and designers have used this insight to improve the cooling effectiveness,thereby increasing the engine efficiency and reducing the *** this review paper,three important cases are considered:hot-gas ingress;the pre-swirl system;and buoyancy-induced ***,or ingestion,occurs when hot gas from the mainstream gas path is ingested into the wheel-space between the turbine disc and its adjacent *** seals are fitted at the periphery of the system,and sealing flow is used to reduce or prevent ***,too much sealing air reduces the engine efficiency,and too little can cause serious overheating,resulting in damage to the turbine rim and blade *** the flow is three-dimensional and unsteady,there are encouraging signs that simple ‘orifice models’ could be used to estimate the amount of ingress into the *** a pre-swirl system,the cooling air for the gas-turbine blades is swirled by stationary nozzles,and the air is delivered to the blades via receiver holes in the rotating turbine *** the air reduces its temperature relative to the rotating blades,and the designer needs to calculate the air temperature and pressure drop in the *** designer also needs to calculate the effect of this swirling flow on the heat transfer from the turbine disc to the air,as this has a significant effect on the temperature distribution and stresses in the *** experimental and computational studies have given a better understanding of the flow and heat transfer in these ***-induced flow occurs in the cavity between two co-rotating compressor discs when the temperature of the discs is higher than

关键词：燃气涡轮机车空气动力学数学模型旋转式圆盘系统

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Prime gradient noise

Computational Visual Media 2021年第3期7卷 349-362页

作者： Sheldon Taylor owen Sharpe Jiju Peethambaran Graphics&Spatial Computing Lab Dept.of Math&CSSaint Mary’s UniversityHailifaxNSCanadaB3H3C3

Procedural noise functions are fundamental tools in computer graphics used for synthesizing virtual geometry and texture ***,a procedural noise function should be compact,aperiodic,parameterized,and randomly *** lattice noise functions such as Perlin noise,however,exhibit periodicity due to the axial correlation induced while hashing the lattice vertices to the *** this paper,we introduce a parameterized lattice noise called prime gradient noise(PGN)that minimizes discernible periodicity in the noise while enhancing the algorithmic *** utilizes prime gradients,a set of random unit vectors constructed from subsets of prime numbers plotted in polar coordinate *** map axial indices of lattice vertices to prime gradients,PGN employs Szudzik pairing,a bijection F:N2→*** of Szudzik pairing functions are used in higher *** the core of PGN is the ability to parameterize noise generation though prime sequence offsetting which facilitates the creation of fractal noise with varying levels of heterogeneity ranging from homogeneous to hybrid multifractals.A comparative spectral analysis of the proposed noise with other noises including lattice noises show that PGN significantly reduces axial correlation and hence,periodicity in the noise *** demonstrate the utility of the proposed noise function with several examples in procedural modeling,parameterized pattern synthesis,and solid texturing.

关键词： procedural noise procedural texture Perlin noise prime numbers

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Endovascular treatment of vasculogenic erectile dysfunction

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Asian Journal of Andrology 2015年第1期17卷 40-43,I0007页

作者： Edward D Kim Ryan C owen Gregory S White osama o Elkelany Cyrus D Rahnema University of Tennessee Graduate School of Medicine Knoxville TN USA.

The treatment of erectile dysfunction （ED） has been a fascination involving multiple medical specialities over the past century with urologic, cardiac and surgical experts all contributing knowledge toward this multifactorial disease. With the well-described association between ED and cardiovascular disease, angiography has been utilized to identify vasculogenic impotence. Given the success of endovascular drug-eluting stent （DES） placement for the treatment of coronary artery disease, there has been interest in using this same technology for the treatment of vasculogenic ED. For men with inflow stenosis, DES placement to bypass arterial lesions has recently been reported with a high technical success rate. Comparatively, endovascular embolization as an approach to correct veno-occlusive dysfunction has produced astonishing procedural success rates as well. However, after a thorough literature review, arterial intervention is only recommended for younger patients with isolated vascular injuries, typically from previous traumatic experiences. Short-term functional outcomes are less than optimal with long-term results yet to be determined. In conclusion, the hope for a minimally invasive approach to ED persists but additional investigation is required prior to universal endorsement.

关键词： erectile dysfunction impotence penile erection vasculogenic

Detecting the ?ngerprints of observed climate change on surface ozone variability

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Science Bulletin 2019年第6期64卷 359-360页

作者： owen R.Cooper Cooperative Institute for Research in Environmental Sciences University of Colorado NoAA Earth System Research Laboratory

At the surface, tropospheric ozone is an air pollutant that adversely impacts human health, natural vegetation and crop yield and quality. This important trace gas also plays key roles as a greenhouse gas, and as the primary source of the hydroxyl (oH) radical, which determines the lifetime of many other trace gases in the atmosphere. Tropospheric ozone has a variety of sources including photochemical production from anthropogenic and naturally occurring precursor gases, and transport from the stratosphere. As a result of 让s high reactivity and its wide range of sources,*sozone lifetime can vary from minutes in the polluted boundary layer to several weeks in the mid- and upper troposphere.

关键词： tropospheric ozone greenhouse gas polluted boundary layer

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The presence and influence of glacier surging around the Geladandong ice caps,North East Tibetan Plateau

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Advances in Climate Change Research 2021年第3期12卷 299-312页

作者： owen KING Atanu BHATTACHARYA Tobias BoLCH Department of Geography and Sustainable Development University of St AndrewsSt AndrewsKY169ALUK Department of Remote Sensing and GIS JIS UniversityKolkata700109India

Many glaciers and ice caps on the Tibetan Plateau have retreated and lost mass in recent years in response to temperature increases,providing clear evidence of the impact of climate change on the *** is increasing evidence that many of the glaciers on the Tibetan Plateau have also shown periodically dynamic behaviour in the form of glacier surging and some even catastrophic collapse *** this study,we examine the prevalence of glacier surging at the Geladandong ice caps,North East Tibetan Plateau,to better understand the role of surge events in the evolution of glacier mass loss *** glacier surface elevation change data over the period 1969—2018 and glacier surface velocity data from the ITS_LIVE dataset,we find that 19 outlet glaciers of the ice caps are of *** multi-temporal measurements of glacier mass balance show that surge-type glacier mass budgets vary depending on the portion of the surge-cycle captured by geodetic *** the regional level,pre-and post-surge glacier mass loss variability does not bias regional mass budget estimates,but enhanced,or suppressed,mass loss estimates are likely when small groups of glaciers are *** results emphasise the importance of accurate surge-type glacier inventories and the need to maximise geodetic data coverage over glacierised regions known to contain surge-type glaciers.

关键词： Glacier surge Remote sensing Corona KH-4 Glacier mass balance ASTER Tibetan Plateau Glacier velocity

Cumulative radiation exposure from diagnostic imaging in intensive care unit patients

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World Journal of Radiology 2016年第4期8卷 419-427页

作者： Fiachra Moloney Daniel Fama Maria Twomey Ruth o'leary Conor Houlihane Kevin P Murphy Siobhan B o'Neill owen J o'Connor Dorothy Breen Michael M Maher Department of Radiology Cork University Hospital Department of Anesthesia Cork University Hospital

AIM:To quantify cumulative effective dose of intensive care unit(ICU)patients attributable to diagnostic ***:This was a prospective,interdisciplinary study conducted in the ICU of a large tertiary referral and level 1 trauma *** and clinical data including age,gender,date of ICU admission,primary reason for ICU admission,APACHE Ⅱ score,length of stay,number of days intubated,date of death or discharge,and re-admission data was collected on all patients admitted over a 1-year *** overall radiation exposure was quantified by the cumulative effective radiation dose(CED)in millisieverts(mS v)and calculated using reference effective doses published by the United Kingdom National Radiation Protection *** patients were selected for ***:A total of 2737 studies were performedin 421 *** total CED was 1704 m Sv with a median CED of 1.5 mS v(IQR 0.04-6.6 mS v).Total CED in pediatric patients was 74.6 mS v with a median CED of 0.07 mS v(IQR 0.01-4.7 mS v).Chest radiography was the most commonly performed examination accounting for 83% of all studies but only 2.7% of total *** tomography(CT)accounted for 16% of all studies performed and contributed 97% of total *** patients received a statistically significant higher dose [median CED 7.7 mS v(IQR 3.5-13.8 mS v)] than medical [median CED 1.4 m Sv(IQR 0.05-5.4 m Sv)] and surgical [median CED 1.6 mS v(IQR 0.04-7.5 mS v)] *** of stay in ICU [oR = 1.12(95%CI:1.079-1.157)] was identified as an independent predictor of receiving a CED greater than 15 mS ***:Trauma patients and patients with extended ICU admission times are at increased risk of higher *** should be minimized where feasible,especially in young patients.

关键词： Cumulative effective dose Pediatric patients Computed tomography Radiation dose Intensive care unit

ENSo and Southeast Asian biomass burning modulate subtropical trans-Pacific ozone transport

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National Science Review 2021年第6期8卷 120-127页

作者： Lian Xue Aijun Ding owen Cooper Xin Huang Wuke Wang Derong Zhou Zhaohua Wu Audra Mc Clure-Begley Irina Petropavlovskikh Meinrat o.Andreae Congbin Fu Joint International Research Laboratory of Atmospheric and Earth System Sciences School of Atmospheric SciencesNanjing University Jiangsu Provincial Collaborative Innovation Center for Climate Change Cooperative Institute for Research in Environmental Sciences University of Colorado Chemical Sciences Division NOAA Earth System Research Laboratory Department of Earth Ocean and Atmospheric SciencesFlorida State University Global Monitoring Division NOAA Earth System Research Laboratory Max Planck Institute for Chemistry Scripps Institution of oceanography University of California

Trans-Pacific transport of enhanced ozone plumes has been mainly attributed to fossil fuel combustion in Asia in spring, but less attention has been paid to vegetation fires in Asia. Here we show that the El Ni?noSouthern oscillation(ENSo)-modulated fires in Southeast Asia, rather than Asian fossil fuel plumes,dominate the interannual variability of springtime trans-Pacific transport of ozone across the entire North Pacific ocean. During El Ni?no springs, the intensified fires from both the Indochinese Peninsula and Indonesia, together with large-scale circulation anomalies, result in enhanced ozone plumes that stretch over 15 000 km in both the lower-middle and upper troposphere. This enhancement is also observed in the in situ measurements of ozone concentration, with an almost 10% increase at Mauna Loa observatory,Hawaii, a unique site to monitor the long-distance transport over the North Pacific. This study reports an unexpectedly strong influence of vegetation fires, linked with climate variability, on global tropospheric chemistry and proves once more how complex the interactions in the climate system are.

关键词： El Niño-Southern oscillation (ENSo) climate biomass burning tropospheric ozone long-range transport Southeast Asia

Chain-to-Chain Competition Under Demand Uncertainty

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Journal of the operations Research Society of China 2016年第1期4卷 49-75页

作者： owen Q.Wu Hong Chen Kelley School of Business Indiana UniversityBloomingtonINUSA Shanghai Advanced Institute of Finance Shanghai 200030China

In this paper,we aim to study the structure choice of supply chains under competitive environment with uncertain *** consider two competing supply chains,each of which chooses to either vertically integrate or decentralize with coordinating *** first analyze firms’strategic behavior under given supply chain structures:two integrated chains(II),two decentralized chains(DD),and a mixed structure with one decentralized chain and one integrated *** then compare different supply chain structures and examine the equilibrium structure *** find that the equilibrium structure depends on the product *** substitutable products,DD is the equilibrium supply chain structure choice,whereas for complementary products,II is the equilibrium ***,a high demand uncertainty strengthens these equilibrium choices.

关键词： coordination Chain-to-chain competition Demand unce