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Thermal effect of a Revolving Gaussian Beam on Activating Heat-Sensitive Nociceptors in Skin

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Journal of Applied Mathematics and Physics 2021年第1期9卷 88-100页

作者： Hongyun Wang wesley A. Burgei Hong Zhou Department of Applied Mathematics University of California Santa Cruz CA USA US Department of Defense Joint Intermediate Force Capabilities Office Quantico VA USA Department of Applied Mathematics Naval Postgraduate School Monterey CA USA

We consider the problem of inducing withdrawal reflex on a test subject by exposing the subject’s skin to an electromagnetic beam. Heat-sensitive nociceptors in the skin are activated wherever the temperature is above the activation temperature. Withdrawal reflex occurs when the activated volume reaches a threshold. Previously we studied static beams with 3 types of power density distribution: Gaussian, super-Gaussian, and flat-top. We found that the flaptop is the best and the Gaussian is the worst in their performance with regard to 1) minimizing the time to withdrawal reflex, 2) minimizing the energy consumption and 3) minimizing the maximum temperature increase. The less-than-desirable performance of Gaussian beams is attributed to the uneven distribution of power density resulting in low energy efficiency: near the beam center the high power density does not contribute proportionally to increasing the activated volume;outside the beam effective radius the low power density fails to activate nociceptors. To overcome the drawbacks of Gaussian beams, in this study, we revolve a Gaussian beam around a fixed point to make the power density more uniformly distributed. We optimize the performance over two parameters: the spot size of static beam and the radius of beam revolution. We find that in comparison with a static Gaussian beam, a revolving Gaussian beam can reduce the energy consumption, and at the same time lower the maximum temperature.

关键词： Heat-Sensitive Nociceptor Heat-Induced Withdrawal Reflex Revolving Gaussian Beam Optimizing energy Consumption Non-Dimensional Analysis

Clinical outcomes after major hepatectomy are acceptable in low-volume centers in the Caribbean

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World Journal of Hepatology 2019年第2期11卷 199-207页

作者： Shamir O Cawich Ravi Maharaj Vijay Naraynsingh Neil Pearce wesley Francis Kimon O Bonadie Dexter A Thomas Department of Clinical Surgical Sciences University of the West Indies Department of Surgery University Hospital Southampton NHS Trust Department Surgery University of the West Indies Department Surgery Cayman Islands Health Service Authority

BACKGROUND Major hepatectomies are routinely performed because they are often the only curative treatment for metastatic liver *** has been a trend to concentrate major hepatectomies in referral hospitals that perform these operations at high *** high volume referral centers are usually located in developed countries,but many patients in developing nations are not able to access these centers because of financial limitations,lack of social support and/or travel ***,local hospitals are often the only options many of these patients have for surgical treatment of metastatic liver *** is the situation in many Caribbean *** To determine the clinical outcomes after major liver resections in a low-resource hepatobiliary center in the *** We prospectively studied all patients who underwent major liver resections over five *** following data were extracted:patient demographics,diagnoses,eCOG status,operation performed,post-operative morbidity and *** analyses were performed using SPSS ver 16.0 ReSULTSThere were 69 major liver resections performed by two teams at a mean case volume of 13.8 major resections/***-nine major hepatic resections were performed for:colorectal liver metastases 40(58%),non-colorectal metastases 9(13%),hepatocellular carcinoma 8(11.6%),ruptured adenomas 4(5.8%),hilar cholangiocarcinomas 4(5.8%),hemangiomata 2(2.9%),trauma 1(1.5%) and hepatoblastoma 1(1.5%).Twenty-one patients had at least one complication,for an overall morbidity rate of 30.4%.There were minor complications in 17(24.6%)patients,major complications in 11(15.9%) patients and 4(5.8%) *** There are unique geographic,political and financial limitations to healthcare delivery in the ***,clinical outcomes are acceptable in the established,low-volume hepatobiliary centers in the eastern Caribbean.

关键词： Liver Surgery Resection Caribbean Volume Outcomes

effect of Depth-Dependent Nociceptor Density on the Heat-Induced Withdrawal Reflex

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Applied Mathematics 2020年第8期11卷 788-824页

作者： Hongyun Wang wesley A. Burgei Hong Zhou Department of Applied Mathematics University of California Santa Cruz CA USA U.S. Department of Defense Joint Intermediate Force Capabilities Office Quantico VA USA Department of Applied Mathematics Naval Postgraduate School Monterey CA USA

Previously we introduced a concise dose-response model for the heat-induced withdrawal reflex caused by millimeter wave radiation. The model predicts the occurrence of withdrawal reflex from the given spatial temperature profile. It was formulated on the assumption that the density of nociceptors in skin is uniform, independent of the depth. The model has only two parameters: the activation temperature of heat-sensitive nociceptors and the critical threshold on the activated volume for triggering withdrawal reflex. In this study, we consider the case of depth-dependent nociceptor density in skin. We use a general parametric form with a scaling parameter in the depth direction to represent the nociceptor density. We analyze system behaviors for four density types of this form. Based on the theoretical results, we develop a methodology for 1) identifying from test data the density form of nociceptors distribution, 2) finding from test data the scaling parameter in the density form, and 3) determining from test data the activation temperature of nociceptors.

关键词： High-energy Millimeter Wave Radiation Heat-Induced Pain Depth-Dependent Nociceptor Density In Skin

Non-Dimensional Analysis of Thermal effect on Skin exposure to an electromagnetic Beam

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American Journal of Operations Research 2020年第5期10卷 147-162页

We consider the problem of inducing withdrawal reflex on a test subject by exposing the subject’s skin to an electromagnetic beam. Heat-sensitive nociceptors in the skin are activated wherever the temperature is above the activation temperature. Withdrawal reflex occurs when the activated volume reaches a threshold. We non-dimensionalize the problem to write the temperature as the product of a parameter-free function of non-dimensional variables and a function of beam parameters. This formulation allows studying beam parameters without knowing skin material parameters. We examine the effects of spot size, total power and distribution type of the electromagnetic beam on 3 quantities at reflex: 1) the time to reflex, 2) the maximum temperature increase, and 3) the total energy consumption. We find that the flat-top beam is the best, with the lowest energy consumption and the smallest maximum temperature increase. The Super-Gaussian beam is only slightly inferior to the flat-top. The Gaussian beam has by far the worst performance among these three.

关键词： Heat-Sensitive Nociceptor Heat-Induced Withdrawal Reflex Radius and Distribution Type of electromagnetic Beam Non-Dimensional Analysis

A pharmacologist's journey in medical education:a personal history

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Acta Pharmacologica Sinica 2004年第9期25卷 102-106页

作者： e e DANIeL AB T6G 2H7 Canada Department of Pharmacology Room 9-10 edmonton MSB University of Alberta

My journey as an educator in Pharmacology began in 1949, when, after finishing my MA in Biology at Johns Hopkins, Ⅰ decided that Ⅰ wanted to be involved in science with more relevance to humans. Ⅰhad been chasing f... 详细信息

关键词： ACe A pharmacologist’s journey in medical education

What We Measure Matters:The Case of the Missing Development Data in Sendai Framework for Disaster Risk Reduction Monitoring

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International Journal of Disaster Risk Science 2021年第6期12卷 779-789页

作者： Ksenia Chmutina Jason von Meding Vicente Sandoval Michael Boyland Giuseppe Forino wesley Cheek Darien Alexander Williams Claudia Gonzalez-Muzzio Isabella Tomassi Holmes Páez Victor Marchezini School of Architecture.Building and Civil engineering.Loughborough University Loughborough LEU 3TU.UK Florida Institute of Built environment Resilience.University of Florida Gainesville.FL 32661USA Disaster Research Unit(DRU) Freie Universitiit Berlin12165 Berlin.Germany Stockholm environment Institute Asia.Bangkok 10330.Thailand School of Geography University of NottinghamNottingham NG72RD.UK Institute of Disaster Mitigation for Urban Cultural Heritage Ritsumeikan University.Kyoto 603-8341Japan Department of Urban Studies and Planning Massachusetts Institute of Technology(MIT)CambridgeMA 02142USA Amhito Consultores Limitada.3565202 Santiago Chile Laboratoire Triangle Lyon.ecole Normale Superieure de Lyon 69342 Rhone-AlpesFrance Department of Civil engineering.Pontificia Universidad Javeriana 110231 BogotaColombia National Centre for Monitoring and Warning of Natural Disasters(CeMADeN).Sao Jose dos Campos SP 12247016Brazil

The Sendai Framework for Disaster Risk Reduction 2015−2030’s(SFDRR)framing moved away from disaster risk as a natural phenomenon to the examination of the inequality and injustice at the root of human vulnerability to hazards and ***,its achievements have not seriously challenged the long-established capitalist systems of oppression that hinder the development leading to disaster risk *** article is an exploratory mapping exercise of and a collective reflection on Sustainable Development Goals(SDGs)and SFDRR indicators-and their use in measuring progress towards disaster risk reduction(DRR).We highlight that despite the rhetoric of vulnerability,the measurement of progress towards DRR remains event/*** argue that the measurement of disaster risk could be greatly enhanced by the integration of development data in future iterations of global DRR frameworks for action.

关键词： Development dynamics Disaster risk root causes Sendai framework for disaster risk reduction Sustainable development goals

Asymptotics and Well-Posedness of the Derived Distribution Density in a Study of Biovariability

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Applied Mathematics 2018年第6期9卷 672-690页

作者： Hongyun Wang wesley A. Burgei Hong Zhou Department of Applied Mathematics and Statistics University of California Santa Cruz CA USA US Department of Defense Joint Non-Lethal Weapons Directorate Quantico VA USA Department of Applied Mathematics Naval Postgraduate School Monterey CA USA

In our recent work (Wang, Burgei, and Zhou, 2018) we studied the hearing loss injury among subjects in a crowd with a wide spectrum of heterogeneous individual injury susceptibility due to biovariability. The injury risk of a crowd is defined as the average fraction of injured. We examined mathematically the injury risk of a crowd vs the number of acoustic impulses the crowd is exposed to, under the assumption that all impulses act independently in causing injury regardless of whether one is preceded by another. We concluded that the observed dose-response relation can be explained solely on the basis of biovariability in the form of heterogeneous susceptibility. We derived an analytical solution for the distribution density of injury susceptibility, as a power series expansion in terms of scaled log individual non-injury probability. While theoretically the power series converges for all argument values, in practical computations with Ieee double precision, at large argument values, the numerical accuracy of the power series summation is completely wiped out by the accumulation of round-off errors. In this study, we derive a general asymptotic approximation at large argument values, for the distribution density. The combination of the power series and the asymptotics provides a practical numerical tool for computing the distribution density. We then use this tool to verify numerically that the distribution obtained in our previous theoretical study is indeed a proper density. In addition, we will also develop a very efficient and accurate Pade approximation for the distribution density.

关键词： Distribution of Individual Injury Susceptibility in a Crowd Biovariability Asymptotic Approximation Pade Approximation

Opportunities and Challenges for Inverse Design of Nanostructures with Sequence Defined Macromolecules

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Accounts of Materials Research 2021年第9期2卷 697-700页

作者： wesley F.Reinhart Antonia Statt Materials Science and engineering Pennsylvania State UniversityUniversity ParkPennsylvania 16802United States Institute for Computational and Data Sciences Pennsylvania State UniversityUniversity ParkPennsylvania 16802United States Materials Science and engineering Grainger College of EngineeringUniversity of IllinoisUrbanaChampaignIllinois 61801United States

Self-assembly of block copolymers has a rich history and has been shown to be a versatile and robust strategy for the bottom-up fabrication of nanostructured functional materials,1 with especially exciting applications in medicine.2 This is due in part to the fact that even blocky sequences composed of a few monomers exhibit rich phase behavior which can be tuned to achieve exotic structures.3,4 However,these simple patterns represent only a tiny fraction of all sequences that can be synthesized in a modern chemistry *** instance,biological proteins which may be composed of dozens of amino acids in arbitrary(and lengthy)sequences can be readily *** it is presently impossible to predict how these complex chemistries lead to structures without experimental or computational trial and error.

关键词： sequences versatile readily

Validation of CFD-DeM model for iron ore reduction at particle level and parametric study

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Particuology 2020年第4期18卷 163-172页

作者： Dianyu e International Research Institute for Minerals Metallurgy and MaterialsJiangxi University of Science and TechnologyNanchang 330013China Department of Chemical engineering Monash UniversityClaytonVIC 3800Australia

Iron ore reduction is a primary unit operation in current metallurgy processes and dominates the energy consumption and greenhouse gas(GHG)emissions of the iron-making process,Therefore,even a slight improvement of the energy efficiency or GHG emissions of iron ore reduction would yield considerable benefits to the cost of pig iron and,more importantly,to mitigation of the associated carbon *** current study presents a discrete model that describes the iron ore reduction process for a single *** transient reaction progress can be predicted and is validated against experimental measurements under various operating conditions,including different reducing gases and *** effects of pressure,isothermality,gas composition,and flow rate on reduction are *** reduction rate increases significantly with increasing pressure until 5 atm,and the entire reduction process occurs more slowly under non-isothermal conditions than under isothermal *** work provides a solid foundation for the development of a comprehensive particulate system model that considers both heat and mass transfer.

关键词： Iron ore reduction Chemical reaction Blast furnace Discrete element method Computational fluid dynamics