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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.app

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

Metabolic collaboration between cells in the tumor microenvironment has a negligible ef.ect on tumor growth

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The Innovation 2024年第2期5卷 107-114页

作者： Johan Gustaf.son f.riba Roshanzamir Anders Hagnestål Sagar M.Patel Oseeyi I.Daudu donald f.Becker Jonathan L.Robinson Jens Nielsen Department of.Lif. Sciences Chalmers University of TechnologySE-41296 GothenburgSweden Hagnesia AB SE-43854 HindåsSweden Department of.Biochemistry and Redox Biology Center University of Nebraska-LincolnLincolnNE 68588USA BioInnovation Institute DK2200 CopenhagenDenmark

The tumor microenvironment is composed of.a complex mixture of.dif.erent cell types interacting under conditions of.nutrient deprivation,but the metabolism therein is not f.lly understood due to dif.iculties in measuring metabolic f.uxes and exchange of.metabolites between dif.erent cell types in ***-scale metabolic modeling enables estimation of.such exchange f.uxes as well as an opportunity to gain insight into the metabolic behavior of.individual cell ***,we estimated the availability of.nutrients and oxygen within the tumor microenvironment using concentration measurements f.om blood together with a metabolite dif.usion *** addition,we developed an approach to ef.iciently apply enzyme usage constraints in a comprehensive metabolic model of.human *** combined modeling reproduced severe hypoxic conditions and the Warburg ef.ect,and we f.und that limitations in enzymatic capacity contribute to cancer cells’pref.rential use of.glutamine as a substrate to the citric acid ***,we investigated the common hypothesis that some stromal cells are exploited by cancer cells to produce metabolites usef.l f.r the cancer *** identif.ed over 200 potential metabolites that could support collaboration between cancer cells and cancer-associated f.broblasts,but when limiting to metabolites previously identif.ed to participate in such collaboration,no growth advantage was *** work highlights the importance of.enzymatic capacity limitations f.r cell behaviors and exemplif.es the utility of.enzyme-constrained models f.r accurate prediction of.metabolism in cells and tumor microenvironments.

关键词： metabolism ef.ect limitations

The Importance of.Posterior Tibial Slope in TKR: Pre and Post-Operative Measurements in United States Osteoarthritic Patients

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Open Journal of.Orthopedics 2024年第8期14卷 374-379页

作者： f.ederick f. Buechel Sr f.ederick f. Buechel Jr Rutgers New Jersey Medical School Department of Orthopaedic Surgery Newark USA Lenox Hill Hospital Department of Orthopaedic Surgery New York USA

Background: Sagittal plane placement of.the tibial component in total knee replacement (TKR) has important implications f.r maximizing the range of.f.exion motion, allowing collateral ligaments to f.nction more normally, as well as providing ideal compressive loading on the tibial bone-prosthesis interf.ce. This study attempts to quantif. the normal posterior tibial slope (PTS) angle pre-operatively and post-operatively in osteoarthritic patients af.er using a conventional extramedullary tibial resection guide to assess its ef.ectiveness. Methods: f.rty-nine primary cementless total knee replacements in 34 osteoarthritic patients were measured radiographically pre-operatively and one year post-operatively to determine the PTS and its ef.ect on range of.motion. Lateral X-rays, using the anterior cortical line of.the tibia, were employed f.r all measurements. Results: Pre-operative PTS measured 11.83˚ (range 5˚ - 18˚), while post-operative PTS of.implanted tibial components measured 11.30o (range 4˚ - 18˚). The pre-operative range of.motion of.112˚ (range 30˚ to 135˚) was improved to 119˚ (range 90˚ to 135˚) post-operatively af.er 1 year. Conclusions: Anterior tibial shaf. ref.rencing using a conventional extramedullary tibial resection guide provides an easy and convenient method f.r reproducing the anatomical PTS during TKR. This methodology provided improvement in average range of.motion f.om 112˚ pre-operatively to 119˚ post-operatively at one year.

关键词： Posterior Tibial Slope Posterior Tibial Inclination Extramedullary Tibial Resection Guide Total Knee Alignment

Clinical studies in COVID-related olf.ctory disorders:Review of.an institutional experience

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World Journal of.Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 129-136页

作者： Theresa Tharakan Dorina Kallogjeri Jay f.Piccirillo Department of.Otolaryngology-Head and Neck Surgery Clinical Outcomes Research OfficeSchool of MedicineWashington University in St LouisSt LouisMissouriUSA

Objective:To share a single institutional experience with clinical research on COVID-related olf.ctory dysf.nction(OD).Data Source/Method:Narrative review of.published original data and ongoing clinical trials on COVID-related OD at Washington University f.om 2020 to ***:There were three new diagnostic-/patient-reported outcome measures developed and *** report f.ve clinical trials of.interventions f.r COVID-related olf.ctory disorders:combined Visual-Olf.ctory Training(VOLT)with patient-pref.rred scents versus standard olf.ctory training(VOLT trial),oral gabapentin versus placebo(Gabapentin f.r the Relief.of.Acquired Chemosensory Experience trial),nasal theophylline irrigations versus placebo(Smell Changes and Ef.icacy of.Nasal Theophylline trial),stellate ganglion block(single-arm),and mindf.lness-based stress reduction(MBSR)versus lif.style intervention(MBSR trial).Conclusions:Initial intervention trials f.r COVID-related OD have shown potential f.r improving subjective and objective olf.ctory ***,there remains no gold standard treatment that def.nitively outperf.rms placebo in controlled ***,continued investigation of.novel therapeutic strategies f.r COVID-related OD is necessary to maximize olf.ctory outcomes f.r af.ected patients.

关键词： chemosensory disorders COVID olf.ctory dysf.nction

On an Invariant of.Tournament Digraphs

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Journal of.Applied Mathematics and Physics 2024年第7期12卷 2711-2722页

作者： Boris f. Melnikov Bowen Liu f.culty of.Computational Mathematics and Cybernetics Shenzhen MSU-BIT University Shenzhen China

To date, it is unknown whether it is possible to construct a complete graph invariant in polynomial time, so f.st algorithms f.r checking non-isomorphism are important, including heuristic algorithms, and f.r successf.l implementations of.such heuristics, both the tasks of.some modif.cation of.previously described graph invariants and the description of.new invariants remain relevant. Many of.the described invariants make it possible to distinguish a larger number of.graphs in the real time of.a computer program. In this paper, we propose an invariant f.r a special kind of.directed graphs, namely, f.r tournaments. The last ones, f.om our point of.view, are interesting because when f.xing the order of.vertices, the number of.dif.erent tournaments is exactly equal to the number of.undirected graphs, also with f.xing the order of.vertices. In the invariant we are considering, all possible tournaments consisting of.a subset of.vertices of.a given digraph with the same set of.arcs are iterated over. f.r such subset tournaments, the places are calculated in the usual way, which are summed up to obtain the f.nal values of.the points of.the vertices;these points f.rm the proposed invariant. As we expected, calculations of.the new invariant showed that it does not coincide with the most natural invariant f.r tournaments, in which the number of.points is calculated f.r each participant. So f.r, we have conducted a small number of.computational experiments, and the minimum value of.the pair correlation between the sequences representing these two invariants that we f.und is f.r dimension 15.

关键词： Graph Directed Graph Tournament ?nvariant

Impaired Cognition and Stroke Rehabilitation Outcomes: Are They Related?

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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

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