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A Lattice Boltzmann and Immersed Boundary Scheme for Model Blood Flow in constricted Pipes:Part 1-Steady Flow

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communications in computational Physics 2013年第6期14卷 126-152页

作者： S.c.Fu w.w.F.Leung R.M.c.So Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HomHong Kong

Hemodynamics is a complex problem with several distinct characteristics;fluid is non-Newtonian,flow is pulsatile in nature,flow is three-dimensional due to cholesterol/plague built up,and blood vessel wall is *** order to simulate this type of flows accurately,any proposed numerical scheme has to be able to replicate these characteristics correctly,efficiently,as well as individually and *** the equations of the finite difference lattice Boltzmann method(FDLBM)are hyperbolic,and can be solved using cartesian grids locally,explicitly and efficiently on parallel computers,a program of study to develop a viable FDLBM numerical scheme that can mimic these characteristics individually in any model blood flow problem was *** present objective is to first develop a steady FDLBM with an immersed boundary(IB)method to model blood flow in stenoic artery over a range of Reynolds *** resulting equations in the FDLBM/IB numerical scheme can still be solved using cartesian grids;thus,changing complex artery geometry can be treated without resorting to grid *** FDLBM/IB numerical scheme is validated against known data and is then used to study Newtonian and non-Newtonian fluid flow through constricted *** investigation aims to gain insight into the constricted flow behavior and the non-Newtonian fluid effect on this behavior.

关键词： Finite difference method lattice Boltzmann method immersed boundary method blood flow constricted pipe

A ONE-STOP LOGISTIc SERVIcES FRAMEwORK SUPPORTING GLOBAL SUPPLY cHAIN cOLLABORATION

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Journal of Systems Science and Systems Engineering 2016年第2期25卷 229-253页

作者： Amy J.c. Trappey charles V. Trappey Sandy w.c. chang w.T. Lee Tun Nien Hsu Department of Industrial Engineering and Engineering Management National Tsing Hua University Hsinchu Taiwan China Department of Management Science National Chiao Tung University Taiwan China Technology center for Service Industries Industrial Technology Research Institute Taiwan China

A global enterprise must continuously improve the efficiency of logistic operations between supply chain collaborators. Integrating logistic services, resources, and necessary information flows in the supply chain to ensure efficiency and efficacy is critically important to these companies. Global logistic service companies face challenges from their clients to provide logistic services that are cost effective, accurate, and seamlessly integrate material, information and cash flows. In this research, an improved framework for one-stop logistic services is systematically designed, analyzed, and evaluated. The one-stop logistic service framework, defmed in four models, is developed to provide enterprises with integrated and comprehensive services within the global supply chain context. The levels of service importance are assessed using a four categories questionnaire. This research provides a case study of the implementation of one-stop logistic services in the distribution industry and demonstrates the framework operating under different demand conditions. Finally, system dynamics causal evaluation is used to evaluate the advantages of the logistic service framework.

关键词： One-stop logistic services logistic management supply chain management system dynamics modeling

More than mimicry？ Evaluating scope for flicker-fusion as a defensive strategy in coral snake mimics

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current Zoology 2014年第1期60卷 123-130页

作者： Georgia c. TITcOMB David w. KIKUcHI David w. PFENNIG Department of Biology University of North Carolina at Chapel Hill Chapel Hill NC 27599-3280

coral snakes and their mimics often have brightly colored banded patterns, generally associated with warning colora- tion or mimicry. However, such color patterns have also been hypothesized to aid snakes in escaping predators through a ＂flicker-fusion＂ effect. According to this hypothesis, banded color patterns confuse potential predators when a snake transitions from resting to moving because its bands blur together to form a different color. To produce this motion blur, a moving snake＇s bands must transition faster than the critical flicker-fusion rate at which a predator＇s photoreceptors can refresh. It is unknown if coral snakes or their mimics meet this requirement. we tested this hypothesis by measuring the movement speed and color pat- terns of two coral snake mimics, Lampropeltis triangulum campbelli and L. elapsoides, and comparing the frequency of color transitions to the photoreceptor activity of the avian eye. we found that snakes often produced a motion blur, but moving snakes created a blurring effect more often in darker conditions, such as sunrise, sunset, and nighttime when these snakes are often active. Thus, at least two species of coral snake mimics are capable of achieving flicker-fusion, indicating that their color patterns may confer an additional defense aside from mimicry

关键词： coral snake mimicry Flicker-fusion effect cFF Kingsnake Defensive strategy

Precipitation on stacking faults in Mg–9.8wt%Sn alloy

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Journal of Materials Science & Technology 2020年第10期42卷 230-240页

作者： c.Q.Liu c.He H.w.chen J.F.Nie International Joint Laboratory for Light Alloys(Ministry of Education) College of Materials Science and EngineeringChongqing UniversityChongqing400044China Department of Materials Science and Engineering Monash UniversityVictoria3800Australia Electron Microscopy center Chongqing UniversityChongqing400044PR China

In this work,we have systematically investigated precipitation ofβ’-Mg3Sn phase on intrinsic stacking faults I1 and I2 in a Mg-9.8 wt%Sn alloy using aberration-corrected scanning transmission electron *** observed I1 faults are generated by the dissociation of c+a perfect dislocations and bounded by Frank partial dislocations having a Shockley *** ofβ’on I1 involves a shear of 1/3α,similar to its formation directly from theα-Mg ***β’phase often nucleates at one end of an I1 fault due to the interaction between shear strain fields ofβ’and the Shockley component of the Frank partial at that end,and subsequently grows towards the other end of the *** theβ’reaches to the other end,the Shockley partial bounding the lengthening end of theβ’reacts with the Frank partial bounding the fault,generating an a perfect dislocation that can glide away from the precipitate and the *** observed I2 faults are generated by the dissociation of a perfect dislocations and bounded by Shockley *** ofβ’on I2 does not need a shear of 1/3α,since the pre-existing I2 fault already provides an ABcA four-layer structure ofβ’.Thickening of theβ’that has already formed on the I2 involves the successive occurrence of three crystallographically equivalent shears of 1/3αon every second(0002)αplane of theα-Mg *** this thickening mechanism is similar to that of theβ’formed directly from theα-Mg matrix,an a perfect dislocation will be produced when theβ’is thickened to eight layers,and it can again glide away from the precipitate and the fault.

关键词： Heterogeneous precipitation HAADF-STEM Shockley partial dislocation Frank partial dislocation Dislocation reaction

Detection of ca^(2+)-dependent acid phosphatase activity identifies neuronal integrity in damaged rat central nervous system after application of bacterial melanin

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Neural Regeneration Research 2016年第7期11卷 1147-1152页

作者： Tigran R. Petrosyan Anna S. ter-Markosyan Anna S. Hovsepyan Yerevan State Medical University YerevanArmenia SPc"Armbiotechnology"SNPO NAS RA YerevanArmenia

The study aims to confirm the neuroregenerative effects of bacterial melanin （BM） on central nervous system injury using a special staining method based on the detection of ca^2＋-dependent acid phosphatase activity. Twenty-four rats were randomly assigned to undergo either unilateral destruction of sensorimotor cortex （group I; n = 12） or unilateral rubrospinal tract transection at the cervical level （c3-4）（group II; n = 12）. In each group, six rats were randomly selected after surgery to undergo intramuscular injection of BM solution （BM subgroup） and the remaining six rats were intramuscularly in）ected with saline （saline subgroup）. Neurological testing confirmed that BM accelerated the recovery of motor function in rats from both BM and saline subgroups. Two months after surgery, ca^2＋-dependent acid phosphatase activity detection in combination with chilingarian＇s calcium adenoside triphosphate method revealed that BM stimulated the sprouting of fibers and dilated the capillaries in the brain and spinal cord. These results suggest that BM can promote the recovery of motor function of rats with central nervous system injury; and detection of ca^2＋-dependent acid phosphatase activity is a fast and easy method used to study the regeneration-promoting effects of BM on the injured central nervous system.

关键词： nerve regeneration bacterial melanin histochemical analysis rubrospinal tract sensorimotor cortex ca^2+-dependent acid phosphatase activity rats neural regeneration

Iterative signal reconstruction of deliberately clipped SMT signals

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Science china(Information Sciences) 2014年第2期57卷 5-17页

作者： KOLLR Zsolt GAZDA Juraj HORVTH Pter VARGA Lajos KOcUR Duan Budapest University of Technology and Economics Technical University of Koice

Staggered MultiTone(SMT)is a modulation technique showing significantly reduced Adjacent channel Leakage Ratio(AcLR)resulting in a more compact Power Spectrum Density(PSD)for the transmitted signal,than the well-known and already widely adopted Orthogonal Frequency Division Multiple Access(OFDMA)***,the unique spectral properties of an SMT signal could be degraded by a non-linear element(e.g.a Power Amplifier(PA))in the *** baseband clipping can be applied to the transmitted signal,reducing the notable high Peak-to-Average Power Ratio(PAPR).The objective of this paper is to give a brief introduction to the SMT scheme,with a special emphasis on deliberate clipping efects and their *** paper introduces two receiver-oriented iterative methods aiming at the restoration of the baseband Bit Error Rate(BER)performance of a non-clipped *** methods are evaluated and compared based on numerical *** paper concludes with the selection of a possible candidate for use in systems applying deliberately clipped SMT signals.

关键词： clipping SMT iterative decoding nonlinear distortion PAPR

Androgen and bone mass in men

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Asian Journal of Andrology 2003年第2期5卷 148-154页

作者： Annie w.c.Kung Department of Medicine University of Hong Kong Queen Mary Hospital Hong Kong China

Androgens have multiple actions on the skeleton throughout life. Androgens promote skeletal growth and accumulation of minerals during puberty and adolescence and stimulate osteoblast but suppress osteoclast function,... 详细信息

ct>Androgens have multiple actions on the skeleton throughout life. Androgens promote skeletal growth and accumulation of minerals during puberty and adolescence and stimulate osteoblast but suppress osteoclast function, activity and lifespan through complex mechanisms. Also androgens increase periosteal bone apposition, resulting in larger bone size and thicker cortical bone in men. There is convincing evidence to show that aromatization to estrogens was an important pathway for mediating the action of testosterone on bone physiology. Estrogen is probably the dominant sex steroid regulating bone resorption in men, but both testosterone and estrogen are important in maintaining bone formation.

关键词： bone of as et Androgen and bone mass in men in

comments on the release Laboratory Manual for the Human Semen of the 5th edition of the wHO Examination and Processing of

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Asian Journal of Andrology 2010年第1期12卷 59-63页

作者： w. c. L. Ford Obstetrics ＆ Gynaecology Unit Clinical Science at South Bristol University of Bristol St Michael＇s Hospital Bristol BS28EG UK

The authors of the world Health Organization Semen Analysis Manual are to be congratulated on producing a new edition; it is an essential tool to disseminate good practice in andrology. However, the tests described have poor prognostic power to predict a man＇s fertility and show little about the underlying causes of sub-fertility. This commentary urges a revival of research into the diagnosis of male fertility. It suggests that fertility should be regarded as a continuum and that the artificial binary division between fertile and infertile should be abandoned. Models to predict a sub-fertile couple＇s chance of conception in a year should be developed on the basis of prospective data. These models would allow for sophisticated decision making about management. The future lies in the identification of tests to detect underlying pathologies open to specific treatment. Leads such as oxidative stress, defects in the intracellular regulation and the developing field ofproteomics should be explored.

关键词： diagnosis male infertility oxidative stress predictive value of tests sperm count

Enantioselectivity of the Musk Odor Sensation

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复旦学报（自然科学版） 2005年第5期44卷 775-776页

作者： G. Fráter P. Kraft Givaudan Schweiz AG Fragrance Researchberlandstrasse 138 CH-8600 Dübendorf SwitzerlandGivaudan Schweiz AG Fragrance Researchberlandstrasse 138 CH-8600 Dübendorf Switzerland

chiral recognition of substrates is one of the most characteristic phenomena of biological activity. And one of the most fundamental biological activities of chemical substances is their smell. In 1991, Linda Buck and Richard Axel[1] discovered a large multigene family that en codes odorant receptors, for which they were awarded the 2004 Nobel Prize in Medicine and Physiology. These odorant receptors are highly homologous,consist of ca. 320 amino acids, and show a heptahelical transmembrane structure as typical for G-protein-coupled receptors. In the human genome, 347 putative full-length olfactory receptor genes have been identified,which allow via characteristic activation patterns of the associated glomeruli the differentiation of more than 10 000 odorants. Since the odorant receptors are built from enantiomerically pure amino acids, they are themselves chiral. consequently, one would expect a strong diastereomeric interaction, and enantiomeric pairs of odorants should thus differ significantly in both their odor character and their strengths or odor threshold.

关键词：对映体大环麝香气味感受器手性识别