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Experimental Studies on Turbulence Kinetic Energy in Confined Vortex Flows

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Journal of Thermal Science 2000年第1期9卷 10-22页

作者： L. Yan G.H. Vatistas S. Lin Department of Mechanical Engineering Concordia University Montreal Quebec Canada H3G 1M8

Turbulence kinetic energies in confined vortex flows have been studied. The studies were based on the experiments performed in a vortex chamber. In the experiments, a Laser Doppler Anemometry (LDA) was used to perform flow measurements inside the vortex chamber, which provided the data for the kinetic energy analysis. The studies concentrated on the influences of the contraction ratio and the inlet air flow rate on the kinetic energy, and analyzed the characteristics of the kinetic energy in the confined vortex flows, including the distributions of the tangential component, radial component and total turbulence kinetic energy. In the paper, both the experimental techniques and the experimental results were presented. Based on a similarity analysis and the experimental data, an empirical scaling formula was proposed so that the tangential component of the turbulence kinetic energy was dependent only on the parameter of the contraction ratio.

关键词： turbulence kinetic energy vortex flow laser Doppler anemometry.

An Accurate and Scalable Direction-Splitting Solver for Flows Laden with Non-Spherical Rigid Bodies–Part 1:Fixed Rigid Bodies

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Communications in Computational Physics 2023年第9期34卷 1079-1132页

作者： Aashish Goyal Anthony Wachs Department of Chemical and Biological Engineering University of British Columbia2360 East MallV6T 1Z3VancouverBritish ColumbiaCanada Department of Mathematics University of British Columbia1984 Mathematics RoadV6T 1Z4VancouverBritish ColumbiaCanada

Particle-resolved direct numerical flow solvers predominantly use a projection method to decouple the non-linear mass and momentum conservation *** computing performance of such solvers often decays beyond O(1000)cores due to the cost of solving at least one large three-dimensional pressure Poisson problem per time *** parallelization may perform moderately well only or even poorly sometimes despite using an efficient algebraic multigrid preconditioner[38].We present an accurate and scalable solver using a direction splitting algorithm[12]to transform all three-dimensional parabolic/elliptic problems(and in particular the elliptic pressure Poisson problem)into a sequence of three one-dimensional parabolic sub-problems,thus improving its scalability up to multiple thousands of *** employ this algorithm to solve mass and momentum conservation equations in flows laden with fixed non-spherical rigid *** consider the presence of rigid bodies on the(uniform or non-uniform)fixed Cartesian fluid grid by modifying the diffusion and divergence stencils on the impacted grid node near the rigid body *** to[12],we use a higher-order interpolation scheme for the velocity field to maintain a secondorder stress estimation on the particle boundary,resulting in more accurate dimensionless coefficients such as drag C_(d)and lift C_(l).We also correct the interpolation scheme due to the presence of any nearby particle to maintain an acceptable accuracy,making the solver robust even when particles are densely packed in a sub-region of the computational *** present classical validation tests involving a single or multiple(up to O(1000))rigid bodies and assess the robustness,accuracy and computing speed of the *** further show that the Direction Splitting solver is∼5 times faster on 5120 cores than our solver[38]based on a classical projection method[5].

关键词： Highly scalable solver particle-laden flow particle resolved direct numerical simulation incompressible flow non-spherical rigid bodies

Systemic RNAi of V-ATPase subunit B causes molting defect and developmental abnormalities in Periplaneta fuliginosa

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Insect Science 2019年第4期26卷 721-731页

作者： Kazuki Sato Keita Miyata Sota Ozawa Koichi Hasegawa Laboratory of Nematology Department of Applied Biological Sciences Saga University Honjo 1 Saga Japan The United Graduate School of Agricultural Sciences Kagoshima University Korimoto 1-21-24 Kagoshima Japan Department of Biomedical Sciences College of Life and Health Sciences Chubu University Kasugai Aichi Japan Department of Environmental Biology College of Bioscience & Biotechnology Chubu University Kasugai Aichi Japan

The vacuolar (H+)-ATPases (V-ATPases) are ATP-driven proton pumps with multiple functions in many organisms. In this study, we performed structural and functional analysis of vha55 gene that encodes V-ATPase subunit B in the smokybrown cockroach Periplaneta fuliginosa (Blattodea). We observed a high homology score of the deduced amino acid sequences between 10 species in seven orders. RNAi of the vha55 gene in R fuliginosa caused nymphal/nymphal molting defects with incomplete shedding of old cuticles, growth inhibition, as well as bent and wrinkled cuticles of thoraxes and abdominal segments. Since growth inhibition caused by vha55 RNAi did not interfere in the commencement of cockroach molting, molting timing and body growth might be controlled by independent mechanism. Our study suggested V-ATPases might be a good candidate molecule for evolutionary and developmental studies of insect molting.

关键词： Blattodea cockroach molting Periplaneta fuliginosa RNA interference vacuolar-type H+-ATPase

Vacuum Fluctuations, Isolated Systems and Hierarchical Cosmology

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Journal of Systems Engineering and Electronics 1995年第4期6卷 285-298页

作者： P. F Browne (Physics Department, UMIST, P. O. Box 88, Manchester M601QD) Physics Department UMIST P. O. Box 88 Manchester M60 1QD

Einstein's general theory of relativity rests on the convention of constant units for time and length, specified by standards at a fired world point P. It is valid to flatten space-time by choice of unit fields, obtained by applying time dilation and length contraction to standards in accordance with an aether velocity field vg(r,t). Two equally valid descriptions for gravitation result. Cosmology in flat space-time is first developed. Zero-point radiation is renormalized to finite energy Kpoc2 density by inclusion of gravitational self-potential energy density provided that Kpoc2 closes the uni- verse at radius R. It is shown that such a universe satisfies the black hole condition, and hence behaves as an isolated system. A single constant defines a finite universe with respect to any mass, due to self-adjustment of boundary surface. The equivalent Einstein model is found by a units transformation to be de Sitter space-time. Einstein's equations must contain only the cosmological term as source term. The Hubble redshift is shown to emerge in both Doppler-gravitational and frequency-decay guises. By postulating an infinite Cosmos containing universes on a hierarchy of scales specified by a geometric series of constants, it is possible for gravitation and electromagnetism to acquire equal complementary status. Unified field equations are proposed, and the relationship between an electron and a universe is explored. A theoretical value of the Hubble constant emerges, H= 108 km s-1Mpc-1.

关键词： General relativity Unified field Inertial force Hubble redshift.

Clinical outcomes of moderate to severe COVID-19 patients receiving invasive vs. non-invasive ventilation

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Asian Pacific Journal of Tropical Medicine 2021年第4期14卷 176-182页

作者： Zubia Jamil Samreen Khalid Shahid Mumtaz Abbasi Yasir Waheed Jamal Ahmed Department of Medicine Foundation University Medical CollegeFoundation UniversityDHA Phase 1 Islamabad 44000Pakistan Fauji Foundation Hospital Rawalpindi 46000Pakistan Department of Multidisciplinary Lab Foundation University Medical CollegeFoundation UniversityDHA Phase 1 Islamabad 44000Pakistan Department of Pulmonology Fauji Foundation HospitalRawalpindi 46000Pakistan

Objective:To evaluate the in-hospital outcome of moderate to severe COVID-19 patients admitted in High Dependency Unit(HDU)in relation to invasive ***-invasive mode of ***:In this study,the patients required either non-invasive[oxygen≤10 L/min or>10 L/min through mask or nasal prongs,rebreather masks and bilevel positive airway pressure(BiPAP)]or invasive *** analysis of 30-day in hospital mortality in relation to use of different modes of oxygen,Kaplan Meier and log rank analyses were *** the end,independent predictors of survival were determined by Cox regression ***:Invasive ventilation was required by 15.1%patients while 84.9%patients needed non-invasive *** with evidence of thromboembolism,high inflammatory markers and hypoxemia mainly required invasive *** 30-day in hospital mortality was 72.7%for the invasive group and 12.9%for the non-invasive group(1.8%oxygen10 L/min,0.9%oxygen>10 L/min,3.6%rebreather mask and 4.5%BiPAP).The median time from hospital admission to outcome was 7 days for the invasive group and 18 days for the non-invasive group(P19 patients.

关键词： COVID-19 SARS-CoV-2 Non-invasive ventilation Respiratory insufficiency Hypoxia Mechanical ventilation

Open-Label Real-World Pharmacy Purchaser Study of Two Fixed-Dose Combination OTC Cold Treatments;Wick MediNait, Wick DayMed Capsules or a Combination of Both

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Open Journal of Respiratory Diseases 2018年第3期8卷 43-62页

作者： Gillian Phillipson David Ramsey Sue Aspley Ingo Fietze Procter&Gamble International Operations Geneva Business CenterGenevaSwitzerland Procter&Gamble Health Care MasonOHUSA Procter&Gamble Technical Centres Ltd. SurreyUK Center of Sleep Medicine Charité—Universitatsmedizin BerlinBerlinGermany

Acute upper respiratory tract infections, i.e. common colds cause multiple symptoms and affect adults on average 2 - 4 times a year and children 6 - 8 times per year. Thousands of non-prescription, over-the-counter products are used by sufferers, aimed at relieving the various both er some symptoms such as cough, nasal congestion, sore throat, etc. This study evaluated real-world effectiveness of Wick MediNait or Wick DayMed medicines alone and together in a combination as a day and night treatment regimen. Adult cold sufferers were recruited in pharmacy by pharmacy staff following self-purchase of either Wick MediNait, Wick DayMed capsules, or the combination of DayMed and MediNait. Participants completed online questionnaires before and after product use (evening of the first day for DayMed and the morning after using MediNait at bedtime). For the primary endpoint “Wick MediNait was effective at relieving my symptoms”, there was a statistically significant difference (p 1) in the users who Strongly Agreed or Agreed vs. Neither Agreed or Disagreed, Disagreed or Strongly Disagreed. Further, all symptoms evaluated (cough, runny nose, nasal congestion, fever, headache, sore throat, muscle aches and pains, sneezing) were statistically improved after MediNait and DayMed alone and when both were used, and users were satisfied with both treatments. All treatments were well tolerated with minimal adverse event reporting. The diurnal use of DayMed capsules combined with the nocturnal use of MediNait allows cold sufferers to efficiently self-manage their symptom relief throughout the day and night.

关键词： Wick MediNait Real-World Use User Satisfaction Observational Cold Symptom Relief Sleep Quality

Neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios alone or combined with prostate-specific antigen for the diagnosis of prostate cancer and clinically significant prostate cancer

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Asian Journal of Urology 2023年第2期10卷 158-165页

作者： Sat Prasad Nepal Takehiko Nakasato Takashi Fukagai Yoshio Ogawa Yoshihiro Nakagami Takeshi Shichijo Jun Morita Yoshiko Maeda Kazuhiko Oshinomi Tsutomu Unoki Tetsuo Noguchi Tatsuki Inoue Ryosuke Kato Satoshi Amano Moyuru Mizunuma Masahiro Kurokawa Yoshiki Tsunokawa Sou Yasuda Department of Urology Department of MedicineShowa University School of Medicine1-5-8 HatanodaiShinagawa-kuTokyoJapan

Objective:We evaluated whether the blood parameters before prostate biopsy can diagnose prostate cancer(PCa)and clinically significant PCa(Gleason score[GS]7)in our ***:This study included patients with increased prostate-specific antigen(PSA)up to 20 ng/*** associations of neutrophil-to-lymphocyte ratio(NLR)and platelet-tolymphocyte ratio(PLR)alone or with PSA with PCa and clinically significant PCa were ***:We included 365 patients,of whom 52.9%(193)had PCa including 66.8%(129)with GS of≥*** density(PSAD)and PSA had better the area under the curve(AUC)of 0.722 and 0.585,respectively with pZ0.001 for detecting PCa compared with other blood *** combined with PLR(PsPLR)and PSA with NLR(PsNLR)had better AUC of 0.608 and 0.610,respectively with p1:PsNLRþbaseline parameters)or PSA and PLR(Moder 2:PsPLRþbaseline parameters)were *** parameters comprised age,digital rectal exam-positive lesions,PSA density,free/total PSA,and magnetic resonance *** 2 containing PsPLR was statistically significant(odds ratio:2.862,95% confidence interval:1.174-6.975,p=0.021)in finding aggressive *** predictive accuracy of Model 2 was increased(AUC:0.734,p1)than that when only baseline parameters were used(AUC:0.693,p1).Conclusion:NLR or PLR,either alone or combined with PSA,did not detect ***,the combined use of PSA with PLR could find the differences between clinically significant and insignificant PCa in our retrospective study limited by the small number of samples.

关键词： Blood parameter Gleason score Neutrophil-tolymphocyte ratio Platelet-tolymphocyte ratio Prostate cancer

Physical features and analysis of traditional mosques:the case of Quzzat quarter of Herat Old City,Afghanistan

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Built Heritage 2023年第3期7卷 1-17页

作者： Ghulam Mohammad Asim Hajime Shimizu Faculty of Engineering and Science The University of the Ryukyus1 Aza-SenbaruNishihara-ChoNakagami-GunOkinawa903-0213Japan

This study examines the physical features of traditional mosques in the Quzzat(Bardrani)quarter of Herat Old City,*** mosques are constructed with locally available materials and are planned based on cultural and climatic *** are categorised as modern or *** mosques are divided into three subcategories:preserved,damaged(defaced),and *** mosques are formerly traditional mosques reconstructed with modern or industrial materials(concrete and reinforcement).This study explores the distribution of mosques and analyses their plan *** are categorised into five plan types,and three relative case studies are described in detail to provide a better understanding and an in-depth analysis of mosque typology.

关键词： Physical features Spatial and architectural analyses Traditional mosques Built heritage conservation Herat Old City Afghanistan

A Self-Powered Nanogenerator for the Electrical Protection of Integrated Circuits from Trace Amounts of Liquid

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Nano-Micro Letters 2020年第1期12卷 54-62页

作者： Zhuang Hui Ming Xiao Daozhi Shen Jiayun Feng Peng Peng Yangai Liu Walter WDuley YNorman Zhou Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of GeosciencesBeijing 100083People’s Republic of China Department of Mechanics and Mechatronics Engineering Centre for Advanced Materials JoiningUniversity of WaterlooWaterlooON N2L 3G1Canada School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191People’s Republic of China Waterloo Institute of Nanotechnology University of WaterlooWaterlooON N2L 3G1Canada Institute for Quantum Computing University of WaterlooWaterlooON N2L 3G1Canada State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Department of Physics and Astronomy University of WaterlooWaterlooON N2L 3G1Canada

With the increase in the use of electronic devices in many different environments,a need has arisen for an easily implemented method for the rapid,sensitive detection of liquids in the vicinity of electronic *** this work,a high-performance power generator that combines carbon nanoparticles and TiO2 nanowires has been fabricated by sequential electrophoretic deposition(EPD).The opencircuit voltage and short-circuit current of a single generator are found to exceed 0.7 V and 100μA when 6μL of water was *** generator is also found to have a stable and reproducible response to other *** output voltage of 0.3 V was obtained after 244,876,931,and 184μs,on exposure of the generator to 6μL of water,ethanol,acetone,and methanol,*** fast response time and high sensitivity to liquids show that the device has great potential for the detection of small quantities of *** addition,the simple easily implemented sequential EPD method ensures the high mechanical strength of the *** compact,reliable device provides a new method for the sensitive,rapid detection of extraneous liquids before they can impact the performance of electronic circuits,particularly those on printed circuit board.

关键词： Self-powered generator Sub-millisecond response Liquid protection