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Two-Stream Approximation to the Radiative Transf.r Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： f.Momo TEMGOUA L.Akana NGUIMDO DNJOMO Environmental Energy Technologies Laboratory(EETL) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of.Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of.the interaction between solar radiation and the Earth's atmosphere is f.rmalized by the radiative transf.r equation(RTE), whose resolution calls f.r two-stream approximations among other methods. This paper proposes a new two-stream approximation of.the RTE with the development of.the phase f.nction and the intensity into a third-order series of.Legendre polynomials. This new approach, which adds one more term in the expression of.the intensity and the phase f.nction, allows in the conditions of.a plane parallel atmosphere a new mathematical f.rmulation of.γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta f.nction and Modif.ed Eddington, and second-order approximation methods with ref.rence to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion f.nction of.the proposed New Method using the f.ndamental def.nition of.two-stream approximation(f.TSA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision f.r wide domains of.the zenith angle μ 0, but tends to deviate f.om the Disort method with the zenith angle, especially f.r high values of.optical thickness. In spite of.this divergence in ref.ectance f.r high values of.optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained f.r most cases of.optical thickness in this study. An analysis of.the Legendre polynomial series f.r simple f.nctions shows that the high precision is due to the f.ct that the approximated f.nctions ameliorate the accuracy when the order of.approximation increases, although it has been proven that there is a limit order depending on the f.nction f.om which the precision is lost. This observation indicates that increasing the order of.approximation of.the phase f.nction of.the RTE lead

关键词： Radiative Transf.r Equation two-stream method Legendre polynomial optical thickness moments of.specif.c intensity conversion f.nction transmittance ref.ectance

f.brication and Electromagnetic Wave Absorption Perf.rmance of.C/C Composites Modif.ed by SiC Nanowires

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Impaired Cognition and Stroke Rehabilitation Outcomes: Are They Related?

Rengong Jingti Xuebao/Journal of.Synthetic Crystals 2024年第5期53卷 889-898页

作者： Gui K. Luo X. Liu f. Zhao X. School of.Materials Science and Engineering Anhui Polytechnic University Wuhu 241000 China

C / C composites have a wide range of.applications in aerospace materials due to their low density, high temperature resistance and other characteristics. Improving the microwave absorbing perf.rmance of.these materials through modif.cation methods is expected to broaden their application f.elds. In this paper, C / C composite, SiC nanowire (SiCnw ), and SiCnw modif.ed C / C composite were f.bricated by precursor inf.ltration and pyrolysis method, and chemical vapor reaction method using phenolic resin, Si, SiO2 and catalyst f.rrocene as raw materials. The microstructures and properties of.C / C and SiCnw / C / C composites were studied, and the inf.uence of.SiCnw content to electromagnetic wave absorption perf.rmance of.C / C composites was discussed. The results show that SiCnw with core / shell structure is successf.lly introduced into C / C composite, and the SiCnw / C / C composite exhibits excellent electromagnetic wave absorption perf.rmance with the increasing of.SiCnw content, and the minimum ref.ection loss of.SiCnw / C / C composite with 15. 4% (mass f.action) SiCnw is - 38. 02 dB with a thickness of.2. 07 mm, signif.cantly lower than those of.other materials. This work provides a technical and theoretical basis f.r the preparation of.high-perf.rmance carbon / ceramic composites. © 2024 Chinese Ceramic Society. All rights reserved.

关键词： carbon f.ber catalyzer chemical vapor reaction composite electromagnetic wave absorption perf.rmance SiC nanowire

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Open Journal of.Therapy and Rehabilitation 2024年第2期12卷 101-116页

作者： Eric f. Tanlaka Torri Trojand f.culty of.Nursing University of Windsor Windsor Canada

Background: Stroke survivors who exhibit impaired cognition at admission to inpatient rehabilitation may experience participation challenges and poorer f.nctional outcomes than those without impaired cognition. Dif.erences in f.nctional outcomes between stroke survivors with and without impaired cognition may be attributed to age, level of.cognitive impairment, and severity of.stroke. Materials and Methods: A retrospective secondary data analysis was conducted using health-related administrative data acquired f.om a Southwestern Ontario hospital’s stroke rehabilitation database. The aim was to explore potential linkages between post-stroke impaired cognition and f.nctional gains, rehabilitation stays, and living settings af.er discharge f.om rehabilitation. Results: An aggregate sample of.393 males and 314 f.males subclassif.ed as experiencing mild, moderate, and severe stroke was analyzed. At inpatient rehabilitation admission, 21.5% (n = 152) of.these patients had no impaired cognition, 33.7% (n = 238) had mild impaired cognition, 22.2% (n = 157) had moderate impaired cognition, and 22.6% (n = 160) had severe impaired cognition. Cognitively impaired stroke patients were signif.cantly (p 0.001) older, had (mostly) moderate to severe stroke with signif.cantly (p = 0.012) more moderate cognitive impairment, had signif.cantly (p 0.001) longer rehabilitation stays, and a high propensity f.r being discharged to longer-term care f.cilities compared to non-cognitively impaired patients. Conclusion: Presence of.signif.cant dissimilarity in rehabilitation stays and post-discharge destinations among stroke survivors with and without cognitive impairment is attributed to the age of.the patient, level of.cognitive impairment, and rigorous rehabilitation interventions.

关键词： Stroke Impaired Cognition Inpatient Rehabilitation f.nctional Outcomes

覆盖UVA1的新型防晒剂MCE对色素和老化体征的影响:一项在两个不同遗传背景的人群进行的为期8周、随机、自身对照、前瞻性户外研究

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中华皮肤科杂志 2024年第6期57卷 579-580页

作者： f. f.ament D. G. Mercurio B. Muller J. Li C. Tricaud f. Bernerd A. Roudot D. Candau T. Passeron L'Oréal Research and Innovation Clichy France L'Oréal Research and Innovation Rio de Janeiro Brazil L'Oréal Research and Innovation Shanghai China L'Oréal Research and Innovation Aulnay-sous-Bois France L'Oréal Research and Innovation Chevilly-Larue France CHU Nice Department of Dermatology Université Côte d'Azur Nice France Université Côte d'Azur INSERM U1065 C3M Nice France

一、引言在不同的紫外线(UV)波段中,长波UVA(UVA1,340~400nm)具有更高的皮肤穿透力,并且受气象条件和臭氧层厚度等环境参数的影响较小,因此更容易到达皮肤深部的真皮层,对细胞成分(如DNA、脂质和蛋白质)造成氧化损伤。UVA1已经越来越多... 详细信息

一、引言在不同的紫外线(UV)波段中,长波UVA(UVA1,340~400nm)具有更高的皮肤穿透力,并且受气象条件和臭氧层厚度等环境参数的影响较小,因此更容易到达皮肤深部的真皮层,对细胞成分(如DNA、脂质和蛋白质)造成氧化损伤。UVA1已经越来越多地被发现与衰老、致癌作用、多种皮肤疾病和色素问题相关。

关键词： UVA1 真皮层自身对照致癌作用皮肤疾病防晒剂遗传背景氧化损伤

Microstructuring of.titanium surf.ces with plasma-modif.ed titanium particles by cold spraying

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Particuology 2019年第3期17卷 90-104页

作者： P. Breuninger f. krull S. Buhl A. Binder R. Merz M. Kopnarski B. Sachweh S. Antonyuk Technische Universitat Kaiserslautern Institute of Particle Process Engineering Kaiserslautern Germany BASf.E Ludwigshafen Germany If.S GmbH Institute for Surface and Thin Film Analysis GmbH Kaiserslautern Germany

Although the deposition mechanisms of.the cold spray process are well studied, f.w reports regarding the use of.surf.ce-modif.ed particles exist. Herein, titanium particles 3-39 μm in size and with an angular shape were modif.ed in a plasma-enhanced chemical vapor deposition process in Ar, Ar-C2H2, and N2 plasmas. Af.er Ar-C2H2 and N2 treatments, the respective presence of.TiC and TiN on the particle surf.ce was conf.rmed via transmission electron microscopy and energy-dispersive X-ray, X-ray photoelectron, and Raman spectroscopies. The powders were deposited on titanium substrates by cold spray experiments, where unmodif.ed particles up to 10(xm in size exhibited a successf.l surf.ce bon ding. This f.nding was described by an existing analytical model, whose parameters were achieved by computational f.uid dynamics simulations taking the particle shape f.ctor into account:. A good deposition of.plasma-modif.ed particles up to 30 μm in size was experimentally observed, exhibiting an upper size limit larger than that predicted by the model. Higher surf.ce roughness values were f.und f.r plasmamodif.ed particles, as determined by 3D scanning electron microscopy. The water contact angle indicated that argon treatment inf.uenced the wettability. Tribological tests showed a decrease of.the initial f.iction coef.icient f.om 0.53 to 0.47 by microstructuring.

关键词： Chemical vapor deposition Cold spray Surf.ce modif.cation Computational f.uid dynamics

An unexpected cellular f.untain of.youth:platelets provide f.ctors rejuvenating brain f.nctions

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Signal Transduction and Targeted Therapy 2024年第1期9卷 16-18页

作者： Harald f.Langer Department of.Cardiology AngiologyHaemostaseology and Medical Intensive CareUniversity Medical Centre MannheimMedical Faculty MannheimHeidelberg UniversityMannheimGermany German Centre f.r Cardiovascular Research(DZHK) Partner Site Heidelberg/MannheimMannheimGermany European Center f.r Angioscience Medical Faculty MannheimHeidelberg UniversityMannheimGermany Cardiovascular systems biology Medical Clinic IUniversity Heart Center LübeckLübeckGermany

In a recent manuscript published in Nature,Schroer et al.discovered that platelets and in particular platelet derived Pf.4(CXCL4)are a novel f.ctor,which can rejuvenate the mammalian neuronal system.1 These f.ndings have the potential to trigger an entire new f.eld of.research opening new platelet-derived candidate ef.ector molecules f.r supporting regeneration.

关键词： supporting platelets f.nding

Buechel Pappas Resurf.cing Shoulder Replacement: Evolution and over 40 Years of.Clinical Experience

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Open Journal of.Orthopedics 2024年第5期14卷 218-228页

作者： f.ederick f. Buechel Michael J. Pappas Rutgers NJ Medical School Newark NJ USA South Mountain Orthopaedic Associates South Orange NJ USA New Jersey Institute of.Technology Newark NJ USA

Background: Early exploration of.the semi constrained “f.oating-Socket” total shoulder replacement (TSR) in 1974 led to a prolif.ration of.various unconstrained designs that allowed resection or retention of.the humeral head, depending upon the pathological process involved. Degenerative glenohumeral arthritis with mild to moderate involvement of.subchondral bone allowed f.r a resurf.cing option, while severe humeral head involvement required a partial or f.ll humeral head replacement attached to an intramedullary stem f.r f.xation. All components evolved f.om cemented to cementless application by 1982. The purpose of.this paper is to describe the progression of.Buechel-Pappas (B-P) shoulder replacement development f.om the early 1970’s in both cemented and cement less applications. Methods: Clinical evaluations of.“f.oating-Socket” TSR, f.llowed by B-P stem-type, resurf.cing types, bipolar-type and revision components, all of.which comprise the B-P Shoulder Replacement System, were perf.rmed over a 49-year period. Results: “f.oating-Socket” implants improved the results of.simple, constrained ball-in-socket designs, but generally f.iled by glenoid component loosening in both chimpanzee and human applications. Unconstrained resurf.cing-type components, both anatomical humeral head and f.ll proximal humeral components, were quite successf.l, with minimal f.ilures observed in long-term studies. Bipolar salvage implants, used f.r severe proximal def.ciencies, revisions and massive rotator cuf. arthropathy, were also very successf.l;providing overhead range of.motion in many patients. Conclusions: Resurf.cing hemiarthroplasty, in patients with intact or repairable rotator cuf. mechanisms, gave the most satisf.ctory results and were the least technically complicated to perf.rm, requiring minimal instrumentation. Resurf.cing of.f.ll proximal humeral def.ciencies, using f.moral resurf.cing components, gave similar clinical results to more complex semi-constrained devices, also with less technical dif.iculties and simple

关键词： Total Shoulder Replacement Resurf.cing Shoulder Replacement

Soil nutrient stoichiometric ratios and their inf.uencing f.ctors in mountainous areas of.the Ili River Valley

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Premature axon-oligodendrocyte interaction contributes to stalling of.experimental axon regeneration af.er injury to the white matter

Zhongshan Daxue Xuebao/Acta Scientiarum Natralium Universitatis Sunyatseni 2024年第3期63卷 60-70页

作者： Yang H. Sun H. Tian Z. Liu T. Wu f. Jin X. School of.Geography and Tourism Xinjiang Normal University Urumqi 830054 China College of.Lif. Science Xinjiang Normal University Urumqi 830054 China

Studying the soil stoichiometric ratios and the inf.uencing f.ctors of.dif.erent altitude gradients in mountain ecosystems in arid zones is signif.cant in revealing the soil nutrient status and maintaining the sustainable development of.mountain ecosystems. In this paper, 13 sample plots were established along the elevation gradient in the mountains of.the southern Ili River Valley, and soil in the depth of.0-20 cm was studied to investigate nutrient stoichiometric ratios and their inf.uencing f.ctors. The results showed that: (1) Soil acidity gradually increased with elevation. Organic carbon and total nitrogen contents are signif.cantly higher in the middle and high mountain belts than in the low mountain belts, while total phosphorus and total potassium contents are opposite. (2) Due to altitudinal dif.erences, the carbon-to-nitrogen ratio is signif.cantly higher in the mid-alpine belt than in the low and alpine belts; carbon and phosphorus ratios are signif.cantly higher in the middle and high mountain belts than in the middle and low mountain belts; carbon and potassium ratios are signif.cantly higher in the middle and high mountain belts than in the low mountain belts; nitrogen-phosphorus ratios are higher in the alpine zone, but there is no major dif.erence between the transition zone and the low mountain zone; nitrogen-potassium ratios are much higher in the alpine zone, whereas there is no signif.cant dif.erence between the mid-alpine zone and the transition zone; the dif.erences of.phosphorus/potassium ratios between altitudinal gradients are ignorable. (3) The dominant f.ctors af.ecting the stoichiometric ratios of.soil physicochemical indicators are soil organic carbon (62.4%), total phosphorus (15.9%), and total carbon (13.7%); while the major environmental f.ctors are mean annual soil temperature (27.1%), vegetation index (11.2%), elevation (12.3%), and mean annual atmospheric temperature (3.4%). The study showed that the physicochemical indicators have an important inf.uence on the soil stoichiomet

关键词： Ili River valley mountains impact f.ctor soil nutrients stoichiometric ratio

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Neural Regeneration Research 2024年第3期19卷 469-470页

作者： Ephraim f.Trakhtenberg Department of.Neuroscience University of Connecticut School of MedicineFarmingtonCTUSA

Studies f.om nearly 3 decades ago suggested that,in the central nervous system(CNS),myelination of.axons by oligodendrocytes not only helps improve axonal conductivity but also stabilizes circuitry(Colello and Schwab,1994).Over the years,myelin sheaths produced by oligodendrocytes have been f.und to contain multiple molecules that are inhibitory to axonal growth(e.g.,MAG,NogoA,OMgp,Semaphorins)(Yiu and He,2006;Silver et al.,2014).Af.er white matter injury in the adult CNS,myelin debris f.om damaged axons and dead oligodendrocytes accumulates in the f.rming glial scar and exposes these myelin-associated axon growth-inhibitory molecules to the injured axonal stumps,thereby contributing to the inhibition of.axonal regrowth.During development,CNS axons reach their postsynaptic targets and stop growing bef.re oligodendrocytes appear and myelinate them(f.ran and Peterson,1992;Dangata et al.,1996).Theref.re,myelin-associated axon growth-inhibitory molecules interacting with already grown axons during myelination were thought to block axons f.om promiscuous sprouting and miswiring,thereby stabilizing neural circuitry in the CNS(Colello and Schwab,1994).

关键词： thereby white injury