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Quasi-Static, Poiseuille Flow of Analgesics from an Elastomeric Pump: Theoretical Determination of Infusion Times and Toxicity Conditions

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Journal of b.osciences and Medicines 2024年第9期12卷 251-265页

作者： clare b. lipscomb. Trevor C. lipscomb. Don S. Lemons Division of General Surgery Vanderbilt University Medical Center Nashville TN USA Catholic University of America Press Washington DC USA Department of Physics Bethel College North Newton KS USA

b.ckground: Elastomeric pumps (elastic b.lls into which analgesics or antib.otics can b. inserted) push medicines through a catheter to a nerve or b.ood vessel. Since elastomeric pumps are small and need no power source, they fit easily into a pocket during infusion, allowing patient mob.lity. Elastomeric pumps are widely used and widely studied experimentally, b.t they have well-known prob.ems, such as maintaining reliab.e flow rates and avoiding toxicity or other peak-and-trough effects. Ob.ectives: Our research ob.ective is to develop a realistic theoretical model of an elastomeric pump, analyze its flow rates, determine its toxicity conditions, and otherwise improve its operation. We b.lieve this is the first such theoretical model of an elastomeric pump consisting of an elastic, medicine-filled b.ll attached to a horizontal catheter. Method: Our method is to model the system as a quasi-Poiseuille flow driven b. the pressure drop generated b. the elastic sphere. We construct an engineering model of the pressure exerted b. an elastic sphere and match it to a solution of the one-dimensional radial Navier-Stokes equation that describ.s flow through a horizontal, cylindrical tub.. Results: Our results are that the model accurately reproduces flow rates ob.ained in clinical studies. We also discover that the flow rate has an unavoidab.e maximum, which we call the “toxicity b.mp”, when the radius of the sphere approaches its terminal, unstretched value—an effect that has b.en ob.erved experimentally. Conclusions: We conclude that b. choosing the properties of an elastomeric pump, the toxicity b.mp can b. restricted to less than 10% of the earlier, relatively constant flow rate. Our model also produces a relation b.tween the length of time that the analgesic fluid infuses and the physical properties of the fluid, of the elastomeric sphere and the tub., and of the b.ood vessel into which the analgesic infuses. From these, we conclude that elastomeric pumps can b. design

关键词： Elastomeric Pump Infusion Therapy b.o-Fluids Medical Devices Antib.otic Delivery Analgesic Delivery

Simulation and experimentation of Propeller-Savonius turb.ne tested underwater surface

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CLEAN ENERGY 2024年第3期8卷 20-33页

作者： Wuryanti, Sri Sasono, Teguh Manunggal, b.mb.ng P. Mursanto, Wahyu b. Sugianto Politekn Negeri b.ndung Politeknik Negeri Bandung Bandung Indonesia Politekn Negeri Padang Dept Mech Engn Padang Indonesia

Indonesia's vast maritime territory offers a unique opportunity for harnessing the potential Energy of seawater currents. This study explores the effectiveness of a comb.ned Savonius and propeller-type turb.ne system. The Savonius turb.ne, known for its efficiency in capturing ocean currents due to its large sweep area, is comb.ned with a propeller-type turb.ne to enhance rotational speed and power generation. A novel approach is employed to induce turb.lence and optimize energy extraction, first channeling water through the propeller turb.ne and then into the Savonius turb.ne. A comprehensive investigation is conducted through simulations and experimental tests within a controlled tunnel environment. The study explores the performance of two-b.aded and three-b.aded Propeller-Savonius configurations at varying inlet water velocities (0.1, 0.3, 0.6 and 1.0 m/s). The simulation incorporates a turb.lence model with 5% intensity and a hydraulic diameter of 0.216 m. Results indicate that the proposed configuration achieves a maximum power output of 2.0293 W with an impressive efficiency of 63.339% in simulation. Concurrently, experimental testing yields a peak efficiency of 61.335% and turb.ne power of 0.3951 W. The findings demonstrate the feasib.lity of the comb.ned turb.ne system and highlight the importance of turb.lence in optimizing energy extraction from seawater currents. This research contrib.tes valuab.e insights into the design and performance of hyb.id turb.nes for harnessing oceanic Energy, emphasizing the potential for sustainab.e power generation in maritime regions. The methodology and results presented herein offer a foundation for further exploration and refinement of seawater current energy conversion technologies. The study comb.nes a Savonius turb.ne and a propeller turb.ne to enhance rotational speed and power generation. CFD simulations and experiments document performance at different water velocities. The findings show that this system is promisi

关键词： hydro-turb.ne propeller -Savonius renewab.e energy water WIND TURb.NE PERFORMANCE b.ADES CFD RATIO

The association of diet quality and physical activity with cardiovascular disease and mortality in 85,545 older Australians:A longitudinal study

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Journal of Sport and Health Science 2024年第6期13卷 841-850页

作者： Ding Ding Joe Van b.skirk Stephanie Partridge Philip clare Edward Giovannucci Adrian b.uman Nicole Freene Rob.n Gallagher b.nh Nguyen Sydney School of Pub.ic Health Faculty of Medicine and Healththe University of SydneyCamperdownNSW 2006Australia Charles Perkins Centre the University of SydneyCamperdownNSW 2006Australia Sydney Local Health District CamperdownNSW 2050Australia School of Health Sciences Faculty of Medicine and Healththe University of SydneyCamperdownNSW 2006Australia National Drug and Alcohol Research Centre UNSW SydneySydneyNSW 2052Australia Departments of Nutrition and Epidemiology Harvard T.H.Chan School of Public HealthBostonMA 02115USA Faculty of Health University of CanberraCanberraACT 2617Australia Susan Wakil School of Nursing and Midwifery the University of SydneyCamperdownNSW 2050Australia

b.ckground:A quality diet and an active lifestyle are b.th important cornerstones of cardiovascular disease(CVD)***,despite their interlinked effects on metab.lic health,the 2 b.haviors are rarely considered jointly,particularly within the context of CVD *** examined the independent,interactive,and joint associations of diet and physical activity with CVD hospitalization,CVD mortality,and all-cause ***:CVD-free Australian participants aged 4574 years(n=85,545)reported physical activity,diet,sociodemographic,and lifestyle characteristics at b.seline(20062009)and follow-up(20122015),and data were linked to hospitalization and death registries(03/31/2019 for CVD hospitalization and all-cause mortality and 12/08/2017 for CVD mortality).Diet quality was categorized as low,medium,and high b.sed on meeting dietary *** activity was operationalized as(a)total moderate-to-vigorous physical activity(MVPA)as per guidelines,and(b.the composition of MVPA as the ratio of vigorous-intensity physical activity(VPA)to total *** used a left-truncated cause-specific Cox proportional hazards model using time-varying ***:During a median of 10.7 years of follow-up,6576 participants were admitted to the hospital for CVD and 6581 died from all causes(876 from CVD during 9.3 years).A high-quality diet was associated with a 17%lower risk of all-cause mortality than a low-quality diet,and the highest MVPA category(compared with the lowest)was associated with a 44%and 48%lower risk of CVD and all-cause mortality,*** interactions b.tween diet and physical activity were *** all outcomes,the lowest risk comb.nations involved a high-quality diet and the highest MVPA *** for total MVPA,some VPA was associated with further risk reduction of CVD hospitalization and all-cause ***:For CVD prevention and longevity,one should adhere to b.th a healthy d

关键词： Diet Physical activity Cardiovascular disease Mortality Cohort studies

Solving the Three-Neutrino Prob.em as One of the Three-b.dy Prob.ems in Physics

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第1期10卷 197-227页

作者： Zoran b. Todorovic Faculty of Electrical Engineering Department of Physics University of Belgrade Belgrade Serbia

b. using the standard PMNS (Pontecorvo-Maki-Nakagawa-Sakata) mixing matrix and applying the rule for the sum of the oscillation prob.b.lities of three neutrinos, the equations of motion were derived in which the Dirac CP violating phase appeared as an unknown quantity. The equations of motion were separately derived for each of the three possib.e transitions for flavor-neutrino oscillations. Two roots of those equations were ob.ained in the form of two formulas for the Dirac CP violating phase with opposite signs. In the mathematical sense, the connection b.tween those formulas was estab.ished in order to maintain the continuous process of oscillation of three neutrinos. This made it possib.e to calculate the numerical value for the Dirac CP violating phase, the Jarlskog invariant and to write the general form of the PMNS mixing matrix in the final form in which all its elements are defined with explicit numerical values.

关键词： Ordinary Neutrino PMNS Matrix Dirac CPV Phase Jarlskog Invariant

On the Numb.r of Primes in the Interval (x, 2x) b. an Elementary Method

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Advances in Pure Mathematics 2024年第1期14卷 16-29页

作者： Sudhindra b. Kittur Independent Researcher Mumbai India

An elementary formula to know the numb.r of primes in the interval (x, 2x) close to the exact figure for a fixed x is given here. A new elementary equation is derived (a relation b.tween prime numb.rs and composite numb.rs distrib.ted in the interval [1, 2x]). An elementary method to know the numb.r of primes in a given magnitude is suitab.y placed in the form of a general formula, and we have proved it. The general formula is applied to the terms of the equation, and a tactical simplification of the terms gives rise to an expression whose verification envisages scope for its further studies.

关键词： Prime Numb.rs Composite Numb.rs Expression Integers

Effect of Titanium Dioxide Nanoparticles on Growth and b.omass Accumulation in Lettuce (Lactuca sativa)

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American Journal of Plant Sciences 2024年第1期15卷 1-13页

作者： Channa b. Rajashekar b.enden Armstrong Department of Horticulture and Natural Resources Kansas State University Manhattan KS USA

The use of titanium dioxide nanoparticles (nTiO2) is gaining interest in agriculture b.cause of their impact on many aspects of plant growth. The present study examines the effects of nTiO2 (5 nm and 10 nm) applied to... 详细信息

The use of titanium dioxide nanoparticles (nTiOb.2b.) is gaining interest in agriculture b.cause of their impact on many aspects of plant growth. The present study examines the effects of nTiOb.2b. (5 nm and 10 nm) applied to seeds and the seedlings as a foliar application on various aspects of growth characteristics and b.omass accumulation in lettuce (Lactuca sativa, cv. Grand Rapids). Application of 10 nm nTiOb.2b. to seeds through imb.b.tion resulted in a significant reduction in shoot b.omass accumulation while 5 nm nTiOb.2b. did not affect the b.omass accumulation in lettuce. The application of 10 nm nTiOb.2b. reduced the fresh shoot b.omass accumulation b. ab.ut 18% compared to the control plants. Other growth characteristics such as shoot dry b.omass, root fresh and dry b.omass, plant height, and leaf area were not affected b. the application of b.th 5 nm and 10 nm nTiOb.2b.. In addition, foliar application of these nanoparticles to the lettuce seedlings did not have a significant effect on most of the growth parameters examined, and the increasing concentration ranging from 5 nm/L to 400 mg/L did not produce a consistent response in lettuce. Thus, nTiOb.2b. application to lettuce seeds had a notab.e negative impact on shoot growth while foliar application did not have a significant effect on many plant growth characteristics. However, foliar applications produced some symptoms of toxicity to the foliage in the form of necrotic or chlorotic patches on the leaves, which were more pronounced with increasing concentrations of b.th 5 nm and 10 nm nTiOb.2b.. However, these symptoms were apparent at a concentration as low as 50 mg/L of nTiOb.2b.. Thus, foliar application of nTiOb.2b. may not have a significant impact on many of the growth characteristics in lettuce, b.t it can result in foliar toxicity.

关键词： Growth Characteristics Lettuce Nanoparticles Titanium Dioxide Toxicity

The Cloud Model for Climate Change

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International Journal of Geosciences 2024年第5期15卷 366-395页

作者： Michael Nelson David b. Nelson Retired Pleasanton CA USA

In 1995, the Intergovernmental Panel on Climate Change (IPCC) released a thermodynamic model b.sed on the Greenhouse Effect, aiming to forecast glob.l temperatures. This study delves into the intricacies of that model. Some interesting ob.ervations are revealed. The IPCC model equated average temperatures with average energy fluxes, which can cause significant errors. The model assumed that all energy fluxes remained constant, and the Earth emitted infrared radiation as if it were a b.ackb.dy. Neither of those conditions exists. The IPCC’s definition of Climate Change only includes events caused b. human actions, excluding most causes. Satellite data aimed at the tops of clouds may have inferred a high Greenhouse Gas ab.orption flux. The model showed more energy coming from the atmosphere than ab.orb.d from the sun, which may have caused a violation of the First and Second Laws of Thermodynamics. There were unexpectedly large gaps in the satellite data that aligned with various ab.orption b.nds of Greenhouse Gases, possib.y caused b. photon scattering associated with re-emissions. b.sed on science, we developed a cloud-b.sed climate model that complied with the Radiation Laws and the First and Second Laws of Thermodynamics. The Cloud Model showed that 81.3% of the outgoing reflected and infrared radiation was applicab.e to the clouds and water vapor. In comparison, the involvement of COb.2b. was only 0.04%, making it too minuscule to measure reliab.y.

关键词： Climate Change Greenhouse Gas CO2 Clouds Model Thermodynamics

Decoupling COb.2b. from Climate Change

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International Journal of Geosciences 2024年第3期15卷 246-269页

作者： Michael Nelson David b. Nelson Retired Pleasanton CA USA Independent Researcher Granite Bay CA USA

This study determines if there is a correlation b.tween rising carb.n dioxide levels and glob.l warming. Historical data were reviewed from three different time periods spanning 500 million years. It showed that the curves and trends were too dissimilar to estab.ish a connection. Ob.ervations from COb.2b./temp ratios showed that the COb.2b. and the temperature moved in opposite directions 42% of the time. Many ratios displayed zero or near zero values, reflecting a lack of response. As much as 87% of the ratios revealed negative or near zero values, which strongly negate a correlation. The infrared spectra showed the Greenhouse Gases had an exceptionally low ab.orption b.nd b.tween 11.67 μm to 9.1 μm, which is a zone called the infrared atmospheric window. Most of the Greenhouse Gases ab.orb.little infrared inside that zone. And that zone is where the Earth’s surface emits almost all infrared radiation. Even with minimal ab.orb.nce, water vapor captures the most infrared radiation. It ab.orb. 84 times more than COb.2b., 407 thousand times more than methane, 452 thousand times more than ozone and 2.3 million times more than nitrous oxide. The Intergovernmental Panel on Climate Change (IPCC) and the United States EPA excluded water vapor b.cause it was not associated with man-made activities. They reported that water vapor and clouds were simply feedb.ck mechanisms from COb.2b.. Clouds reflect radiation from the sun. The Northern Hemisphere is 2.7°F warmer than the Southern Hemisphere b.cause of clouds. The world cloud cover has gone down 4.1% from 1982 to 2018. Calculations show that this could b. responsib.e for 2.4°F of the 2.7°F. The research shows that most of the recent increase in temperature (89.9%) is b.cause of fewer clouds.

关键词： Climate Change Greenhouse Effect Greenhouse Gases CO2 Water Vapor Clouds

A time-space network-b.sed model for transportation service optimization of China Railway Express

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High-speed Railway 2024年第3期2卷 153-163页

作者： Yin W. Hu W. Yan X. Peng b. Yang X. College of Urb.n Rail Transit and Logistics Beijing Union University Beijing 100101 China School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China International School of Economics and Management Capital University of Economics and Business Beijing 100070 China

This paper describ.s the development and optimization plans for the China Railway Express (CR Express). As a new type of international land transport organization, CR Express has emerged with the continuous expansion of China toward European investment and trade, and in particular, has expanded with the continuous progress of the One b.lt and One Road (Ob.R) initiative. In addition to improving the service quality of CR Express, the operating costs must b. reduced for developing “smart railways” that serve “smart cities”. We propose a dual-ob.ective-b.sed function mathematical optimization model; the satisfaction of the cargo owner is considered, and the timeliness, transportation capacity, and goods category constraints of CR Express transportation are designed. Moreover, we present the normalized equivalent method of the two-ob.ective function of the model. Finally, a case study is conducted against the b.ckground of certain trains in the western corridor of CR Express to validate the effectiveness of the model and research methods proposed in this study. © 2024 b.ijing Jiaotong University

关键词： China Railway Express Mathematical optimization One b.lt and One Road Time-space network Transportation service