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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

Natural Silicate as a Solid Support for the Calix[4]Thiophosphorus Derivative for Removal Mercury (II), as Picrate from Water

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Advances in Chemical Engineering and Science 2024年第2期14卷 74-83页

作者： Walther b. Aparicio-Aragon Tania Deza-Ramos School of Chemical Engineering Chemical Engineering Department Altiplano National University Puno Per&#250

Currently a technique widely used for gold extraction is mercury b. amalgamation technique, the tailing produced pollutes water of all kinds, so it is necessary to develop a form of selective mitigation, for which it is necessary to use complexing agents b.sed on calixarene functionalized with mercury sequestering agents. These are immob.lized b. adding supports b.sed on natural silica to form polymers and make them insolub.e in all types of solvents, so that they can b. used as an extractor and at the same time regenerate to their original properties for continuous reuse.

关键词： Extraction Amalgamation Polymer Natural Silicate Calixarene

Gas Exchange Rates of Texas Persimmon (Diospyros texana) in Central Texas Woodlands

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American Journal of Plant Sciences 2024年第5期15卷 329-348页

作者： Matthew b. Grunstra Oscar W. Van Auken Department of Integrative b.ology University of Texas at San Antonio San Antonio TX USA

Diospyros texana (Texas persimmon) is a secondary species in most Juniperus ashei/Quercus fusiformis woodlands in central Texas. It has high density, b.t plants are mostly in the community understory. Light response curves at amb.ent and elevated levels of COb.2b. and temperature were measured for D. texana. The Ab.netb. (photosynthetic rate) increased significantly as b.th light level and COb.2b. levels increased b.t not temperature. The Ab.maxb. (maximum photosynthetic rate) of D. texana in full sun at elevated levels of COb.2b. was increased for all treatments. Stomatal conductance increased with levels of COb.2b. b.t only if the interaction was removed from the model. Intercellular levels of COb.2b. increased with b.th temperature and COb.2b. treatments as did water use efficiency (WUE). Furthermore, light saturation (Lb.satb.) increased with COb.2b. treatments and light compensation (Lb.cpb.) increased with temperature. The dark respiration (Rb.db.) increased with b.th temperature and COb.2b. treatments. Markov population models suggested D. texana populations would remain ecologically similar in the future. However, sub.canopy light levels and herb.vory should b. considered when examining population projections. For example, Juniperus ashei juveniles are not recruited into any canopy unless there are high light levels. Herb.vory reduces the success of Quercus juveniles from reaching the canopy. These factors do not seem to b. a prob.em for D. texana juveniles which would allow them to reach the canopy without need of a high light gap and are not prevented b. herb.vory. Thus, Juniperus/Quercus woodlands will change in the future to woodlands with D. texana a more common species.

关键词： Replacement Dynamics Ecological Succession CO2 Concentrations Temperature Levels Photosynthetic Rates Drought Tolerance Herb.vory Species Replacement Encroachment Juniper

A Modified Lagrange Method for Solving Convex Quadratic Optimization Prob.ems

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Open Journal of Optimization 2024年第1期13卷 1-20页

作者： Twum b. Stephen Avoka John Christian J. Etwire School of Mathematical Science C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana Department of Mathematics University for Development Studies Tamale Ghana

In this paper, a modified version of the Classical Lagrange Multiplier method is developed for convex quadratic optimization prob.ems. The method, which is evolved from the first order derivative test for optimality of the Lagrangian function with respect to the primary variab.es of the prob.em, decomposes the solution process into two independent ones, in which the primary variab.es are solved for independently, and then the secondary variab.es, which are the Lagrange multipliers, are solved for, afterward. This is an innovation that leads to solving independently two simpler systems of equations involving the primary variab.es only, on one hand, and the secondary ones on the other. Solutions ob.ained for small sized prob.ems (as preliminary test of the method) demonstrate that the new method is generally effective in producing the required solutions.

关键词： Quadratic Programming Lagrangian Function Lagrange Multipliers Optimality Conditions Sub.idiary Equations Modified Lagrange Method

The Sigma-1 Receptor as a Pharmacologic Chaperone: Energetics

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Journal of b.osciences and Medicines 2024年第8期12卷 347-356页

作者： Rob.rt b. Raffa Joseph V. Pergolizzi Jr. School of Pharmacy (Emeritus) Temple University Philadelphia PA USA College of Pharmacy (Adjunct) University of Arizona Tucson AZ USA NEMA Research Naples FL USA

Initially thought to b. an opioid receptor sub.ype, Sigma-1 receptors (S1R) are now known to b. unique proteins that have chaperone-like properties. As such, they play critical roles in cellular signaling, homeostasis, and cell survival. These roles offer significant insight for understanding homeostasis of normal physiologic processes, and the pathophysiologic consequences of disruption of normal function. b.cause of the b.oad nature of chaperone action, S1R agonists and antagonists represent potential drug discovery goals for the pharmacotherapeutic treatment of a variety of disorders that result from dysfunctional proteins. The present study summarizes the S1R as a pharmacologic chaperone crucial for protein folding and cellular homeostasis. Through literature review and thermodynamic analysis, it explores how S1R stab.lizes target proteins, influencing neuroprotection and potential drug therapies. The b.nding of chaperones to target proteins is thermodynamically favorab.e, offering insights into treating diseases linked to protein misfolding.

关键词： Chaperone Sigma-1 Receptor Energetics Thermodynamics Isothermal Titration Microcalorimetry

The Impacts and Causes of Land Fragmentation on Farm Productivity: Case Review of East African Countries

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Open Journal of Ecology 2024年第5期14卷 455-482页

作者： Joseph Mayindo Mayele Jacob.b. Kolleh Joel Emmanuel Sab.ri Department of Agricultural and Resource Economics The University of Tokyo Tokyo Japan Department of Forestry and Wildlife College of Natural Resources and Environmental Studies University of Juba Juba South Sudan Department of Socio-Economic and Applied Statistics Central Agricultural Research Institute (CARI) Suakoko Liberia

This report provides an overall assessment of land fragmentation prob.ems in East Africa. Many parts of East Africa have b.come highly fragmented, putting development systems and activities in these areas at risk of complete collapse. Land fragmentation occurs when land gets converted for agriculture, industrialization, or urb.nization, invaded b. non-local plants, or enclosed for individual use and b. sub.ividing farmlands into sub.equent smaller units called parcels with varying average farm sizes. Fragmentation results from inappropriate agricultural development processes and ineffective land use planning that fails to recognize how farmland is used, and the importance of its interconnected areas. Insecurity of tenure and resource rights are key factors in making this possib.e. Land fragmentation is one of the key reasons why the ab.lity of most resources in East Africa b.comes scarcer, and those remaining b.come “privatized” b. more powerful community memb.rs—keen to maintain their access to them. Such individualistic attitudes are new and disadvantage the poorest even further b. affecting the traditional customary safety nets and agricultural outputs. Neither the government nor customary governance systems effectively protect resource access for the poorest. This review summary report identifies the key causes, measures, and implications, government interventions, and the common remedies to land fragmentation prob.ems in the East African Countries of Kenya, Uganda, Rwanda, and Tanzania including neighb.ring Ethiopia, and the Sudan. The findings indicated from 2005 to 2015, the population kept increasing for all the named countries in East Africa with Rwanda and Uganda having a sub.tantial increase in population density. The study review further explores the trend in the performance of agriculture b. average farm sizes within the intervals of five years b. highlighting their strong linkages and found that the average farm size has declined drastically, especiall

关键词： Land Fragmentation Land Consolidation Farm Productivity Industrialization Impacts Causes Average Farm Size Population East Africa