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Chinese journal Of geochemistry 2013年第1期32卷 19-26页

作者： Sajil Kumar P.j. Davis Delson P. vernon j.g. james E.j. Brandenburg Technical University Cottbus-03046 Germany ITALCONSULT Riyadh-11421 Saudi Arabia Budapest University of Technology and Economics (BME) Budapest-Pf. 91 H-152 Hungary Water Institute Karunya UniversityCoimbatore-641114 India

A linear regression model in conjunction with cluster analysis was applied to the groundwater quality parameters for the Vaniyambadi industrial area, Tamil Nadu, India. These physico-chemical parameters were collected from 25 wells by intensive groundwater sampling conducted during january 2010. All the major ions, pH and electrical conductivity were analyzed. The abundances of cations were in the order of Na g greement with the water types, Na-Cl and Na-Ca-HCO3, determined by the Piper plot. High concentrations of the ions Na, Cl and SO4 were recorded near the tanneries that operate within the study area. While the elevated concentrations of HCO3 and F were observed away from the tanneries. This peculiar hydrochemical behaviour suggests that the chemistry of water is predominantly influenced by tannery effluents and weathering of silicate minerals. Results of the linear regression model yielded 11 regression equations for the 5 most correlated parameters. A dendrogram from the cluster analysis showed 2 major clusters representing the influence of tanneries and geological formations in the study area, which confirmed the results of major ion chemistry.

关键词：线性回归模型地下水化学工业区印度 LRM 聚类分析物理化学参数研究区域

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Heuristic Estimation of the Vacuum Energy Density of the Universe: Part II-Analysis Based on Frequency Domain Electromagnetic Radiation

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journal of Electromagnetic Analysis and Applications 2024年第1期16卷 1-9页

作者： vernon Cooray gerald Cooray Marcos Rubinstein Farhad Rachidi Department of Electrical Engineering Uppsala University Uppsala Sweden Karolinska Institute Stockholm Sweden HEIg-VD University of Applied Sciences and Arts Western Switzerland Yverdon-les-Bains Switzerland Electromagnetic Compatibility Laboratory Swiss Federal Institute of Technology (EPFL) Lausanne Switzerland

In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according to which an electron is accelerated to a constant and relativistic speed at a distance L from a perfectly conducting plane. The charge of the electron was represented by a spherical charge distribution located within the Compton wavelength of the electron. Subsequently, the electron is incident on the perfect conductor giving rise to transition radiation. The energy associated with the transition radiation depends on the parameter L. It was shown that an inequality satisfied by the vacuum energy density will emerge when the length L is pushed to cosmological dimensions and the product of the radiated energy, and the time duration of emission is constrained by Heisenberg’s uncertainty principle. In this paper, a similar analysis is conducted with a chain of electrons oscillating sinusoidally and located above a conducting plane. In the thought experiment presented in this paper, the behavior of the energy radiated by the chain of oscillating electrons is studied in the frequency domain as a function of the length L of the chain. It is shown that when the length L is pushed to cosmological dimensions and the energy radiated within a single burst of duration of half a period of oscillation is constrained by the fact that electromagnetic energy consists of photons, an inequality satisfied by the vacuum energy density emerges as a result. The derived inequality is given by where is the vacuum energy density. This result is consistent with the measured value of the vacuum energy density, which is 5.38 × 10-10 j/m. The result obtained here is in better agreement with experimental data than the one obtained in Part I of this paper with time domain radiation.

关键词： Classical Electrodynamics Electromagnetic Radiation Action Radiated Energy Photon Heisenberg’s Uncertainty Principle Dark Energy Vacuum Energy Cosmological Constant Hubble Radius

Creating and moving nanoantenna cold spots anywhere

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Light(Science & Applications) 2022年第10期11卷 2335-2344页

作者： Alex j.vernon Francisco j.Rodriguez-Fortuno Department of Physics King's College LondonStrandLondon WC2R 2LSUnited Kingdom

Cold spots are sub-wavelength regions which might emerge near a nanoantenna,should one or more components of some far-field illumination cancel out with scattered *** show that by changing only the polarisation,amplitude,and phase of two plane waves,a unique,zero-magnitude and highly sub-wavelength cold spot can be created and moved anywhere in the space around a nanoantenna of any arbitrary *** can be achieved using ultra-fast modulated pulses,or a time-harmonic *** disturbed by a change in the nanoantenna's material or position,a manufactured cold spot is fragile and could be used in nanoscale *** technique exploits the linearity of Maxwell's equations and could be adapted to manipulate any phenomena governed by the linear wave equation,including acoustic *** is a means for potentially ultra-fast sub-wavelength electric field manipulation.

关键词： illumination scattered arbitrary

Heuristic Estimation of the Vacuum Energy Density of the Universe: Part I—Analysis Based on Time Domain Electromagnetic Radiation

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journal of Electromagnetic Analysis and Applications 2023年第6期15卷 73-81页

In this paper, an inequality satisfied by the vacuum energy density of the universe is derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according to which an electron is accelerated to a constant and relativistic speed at a distance L from a perfectly conducting plane. The charge of the electron is represented by a spherical charge distribution located within the Compton wavelength of the electron. Subsequently, the electron is incident on the perfect conductor giving rise to transition radiation. The energy associated with the transition radiation depends on the parameter L. It is shown that an inequality satisfied by the vacuum energy density will emerge when the length L is pushed to cosmological dimensions and the product of the radiated energy and the time duration of emission are constrained by Heisenberg’s uncertainty principle. The inequality derived is given by ρΛ ≤ 9.9×10-9j/m3 where ρΛ is the vacuum energy density. This result is consistent with the measured value of the vacuum energy density, which is 0.538 × 10-9j/m. Since there is a direct relationship between the vacuum energy density and the Einstein’s cosmological constant, the inequality can be converted directly to that of the cosmological constant.

关键词： Classical Electrodynamics Electromagnetic Radiation Action Radiated Energy Photon Heisenberg’s Uncertainty Principle Dark Energy Vacuum Energy Cosmological Constant Hubble Radius

An economic analysis of varicella immunization in the Singapore military

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journal of Medical Colleges of PLA(China) 2016年第1期31卷 43-50页

作者： jake j.K.goh Marc Ho W.M.Koh vernon j.Lee Specialist Medicine Centre AFPN 0047 27 Medical Drive #08-01 Singapore 117510 Singapore National University of Singapore MD3 16 Medical Drive Singapore 117597 Singapore

Background:Varicella outbreaks occur frequently in closed environments such as those of *** paper compares the economic outcomes of varicella vaccination in enlisted servicemen without prior reported varicella infection or ***:We analyzed the economic outcomes of a varicella vaccination program on all enlisted servicemen without prior reported varicella infection or vaccination in the Singapore Armed Forces(SAF) between December 11,2010–December 20,2013,compared with the previous program of varicella vaccination only for selected personnel between December 1,2007–December 10,***:In the at-risk population of all active SAF servicemen,the program of varicella vaccination for all servicemen without prior reported varicella infection or vaccination upon enlistment would save 72.0 work days per 1000(95% CI:61.2-82.9),valued at Sg$6,544 per 1000(95% CI:6,524-6,564),i.e.,costing Sg$91.5 per work day saved(95% CI:78.7-107.3).This also results in a reduction of 2.7 varicella cases per 1000 and 5.43 outbreaks per 10000,or a total savings of Sg$1,695 per 1000(95% CI:–2,730-6,834),taking into account the cost of work days lost over a three-year period,compared with the previous regime of vaccinations only for selected ***:The varicella vaccination strategy targeting all enlisted servicemen without prior reported varicella infection or vaccination is able to prevent varicella infections and outbreaks,thus reducing absenteeism and days lost.

关键词： Varicella Vaccination Military Singapore Economic analysis

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中国的城市化:面临的政策问题与选择

城市发展研究 2007年第4期14卷 32-41页

作者： j.vernon Henderson

中国近30年来经济成就巨大.自1978年以来, 人均gDP每年大约增长10%.同一时期, 非农就业人口从占劳动人口的24%增长到60%, 城市人口从占全国的18 %增长到45 %.

关键词：中华人民共和国城市公共服务城乡收入差距市政债券移民者农村劳动力中央政府超大城市劳动生产率土地承包权

Burn injury differentially alters whole-blood and organ glutathione synthesis rates: An experimental model

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Burns & Trauma 2013年第2期1卷 87-94页

作者： Zhe-Wei Fei vernon R. Young Xiao-Ming Lu Andrew B. Rhodes Ronald g.Tompkins Alan j. Fischman Yong-Ming Yu Shriners Burns Hospital and Burn & Trauma Service Massachusetts General Hospital Harvard Medical School Boston MA 02114 Shriners Burns Hospital and Burn & Trauma Service Massachusetts General Hospital Harvard Medical School Boston MA 02114 Laboratory of Human Nutrition Massachusetts Institute of Technology Cambridge MA 02142 USA

Previous studies from our laboratories revealed a reduced rate of whole-blood (WB) glutathione (gSH) synthesis in severely burned patients. To determine whether WB gSH metabolism is an indicator of the status of gSH metabolism in one or more of the major organs, we used a burn rabbit model to determine gSH concentrations and rates of synthesis in WB, liver, lungs, kidney, and skeletal muscle. L-[1-13C]-cysteine was infused intravenously for 6 h in rabbits at 3 days post-burn and in sham burn controls. WB and organ 13C-enrichment of cysteine and gSH was determined by gas chromatography/mass spectrometry. Plasma cysteine metabolic flux was increased significantly (P g burn injury. WB, liver, and lung gSH concentrations (P = 0.054, P gSH synthesis (P gSH transport out of the liver after burn injury. Hence, there is a differential impact of burn injury on tissue and organ gSH status, with WB qualitatively reflecting the changes in lung and liver. It will be important to determine whether these changes are due to alterations in the intrinsic capacity for gSH synthesis and/or availability of amino acid precursors of gSH.

关键词： Burn injury glutathione glutathione concentration synthesis rate whole blood

Eye Disease and Eye Care Needs of West Virginia:Results of the WV Eye Health Survey

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Eye Disease and Eye Care Needs of West Virginia:Results of t...

From oral formulations to drug-eluting implants:using 3D and 4D printing to develop drug delivery systems and personalized medicine

中华医学会第十二届全国眼科学术大会

作者： j.vernon Odom West Virginia University USA

We report results of a several statewide telephone sur- veys conducted in West *** purposes of these sur- veys was 1)to determine the need for low vision *** the state of WV,2)to determine how patients who visited

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Bio-Design and Manufacturing 2022年第1期5卷 85-106页

作者： Niels g.A.Willemen Margaretha A.j.Morsink Devin Veerman Classius F.da Silva juliana C.Cardoso Eliana B.Souto Patrícia Severino Center for Biomedical Engineering Department of MedicineBrigham and Women&HospitalHarvard Medical School65 Landsdowne StreetMA 02139 CambridgeUSA Department of Developmental BioEngineering Faculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteEnschedeThe Netherlands Translational Liver Research Department of Medical Cell BioPhysicsTechnical Medical CentreFaculty of Science and TechnologyUniversity of TwenteEnschedeThe Netherlands Targeted Therapeutics Department of Biomaterials Science and TechnologyFaculty of Science and TechnologyUniversity of TwenteEnschedeThe Netherlands Department of Chemical Engineering Institute of EnvironmentalChemical and Pharmaceutical SciencesFederal University of São PauloRua São Nicolau210Diadema 09913‑030Brazil University of Tiradentes(Unit) and Institute of Technology and Research(ITP)Av.Murilo Dantas300Aracaju 49010‑390Brazil Faculty of Pharmacy University of CoimbraPólo das Ciências da SaúdeAzinhaga de Santa Comba3000‑548 CoimbraPortugal CEB‑Centre of Biological Engineering University of MinhoCampus de Gualtar4710‑057 BragaPortugal Tiradentes Institute 150 Mt Vernon StDorchesterMA 02125USA

Since the start of the Precision Medicine Initiative by the United States of America in 2015,interest in personalized medicine has grown *** short,personalized medicine is a term that describes medical treatment that is tuned to the *** possible way to realize personalized medicine is 3D *** using materials that can be tuned upon stimulation,4D printing is *** recent years,many studies have been exploring a new field that combines 3D and 4D printing with *** has resulted in many concepts of pharmaceutical devices and formulations that can be printed and,possibly,tailored to an ***,the first 3D printed drug,Spritam®,has already found its way to the *** review gives an overview of various 3D and 4D printing techniques and their applications in the pharmaceutical field as drug delivery systems and personalized medicine.

关键词： Drug delivery systems 3D/4D printing Drug-eluting implants Microneedles Oral formulations

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Remarkable Predictions of Classical Electrodynamics on Elementary Charge and the Energy Density of Vacuum

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journal of Electromagnetic Analysis and Applications 2018年第5期10卷 77-87页

作者： vernon Cooray gerald Cooray Department of Engineering Sciences Uppsala University Uppsala Sweden Karolinska Institute Stockholm Sweden

In a recent paper, we have studied the nature of the electromagnetic energy radiated over a single period of oscillation by an antenna working in frequency domain under ideal conditions and without losses when the oscillating charge in the antenna is reduced to the elementary charge. Here we extend and expand that study. The energy radiated by an oscillating current in an antenna occurs in bursts of duration T/2, where T is the period of oscillation. The results obtained here, based purely on classical electrodynamics, can be summarized by the inequality U ≥hv→q0 ≥e where U is the energy radiated in a single burst of duration T/2, h is the Planck constant, ν is the frequency of oscillation and q0 is the magnitude of the oscillating charge associated with the current. The condition U=hv→q0=e is obtained when the length of the antenna is equal to the ultimate Hubble radius of the universe (i.e. the maximum value of the antenna length allowed by nature) and the wavelength is equal to the Bohr radius (resulting from the smallest possible radius of the conductor allowed by nature). The ultimate Hubble radius is directly related to the vacuum energy density. The inequality obtained here is in general agreement with the one obtained in the previous study. One novel feature of this extended analysis is the discovery of an expression, in terms of the elementary charge and other atomic constants, for the vacuum energy density of the universe. This expression predicts the vacuum energy density to be about 4×10-10?j/m3 which is in reasonable agreement with the measured value of 6×10-10 j/m3.

关键词： Classical Electrodynamics Electromagnetic Radiation Oscillating Currents Energy of a Photon Radius of the Universe Hubble Radius Vacuum Energy Dark Energy Elementary Charge Electronic Charge