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Mitochondrial D-loop diversity of grasscutter (<i>Thryonomys swinderianus</i>Rodentia: Hystricomorpha) in Ghana

Open Journal of Animal Sciences 2013年第3期3卷 145-153页

作者： Christopher Adenyo Azusa Hayano boniface b. kayang Erasmus H. Owusu Miho Inoue-Murayama Department of Animal b.ology and Conservation Science Faculty of Science University of Ghana Legon Ghana Department of Animal Biology and Conservation Science Faculty of Science University of Ghana Legon Ghana Department of Animal Science School of Agriculture University of Ghana Legon Ghana Wildlife Research Center Kyoto University Kyoto Japan Wildlife Research Center Kyoto University Kyoto Japan

Attempts are b.ing made to domesticate the grasscutter (Thryonomys swinderianus) for commercial production in Sub.Saharan Africa to cater for the protein needs of the people and to satisfy the craving for b.shmeat, thereb. reducing hab.tat destruction through hunting. The ob.ective of this study was to determine the genetic diversity of grasscutter populations in Ghana. DNA was extracted from roots of hair samples collected from 84 grasscutters from three agro-ecological zones in Ghana, namely Guinea Savanna (n = 17), Forest (n = 22), and Coastal Savanna (n = 45). Mitochondrial D-loop was sequenced and the diversity was determined across the zones. Out of 26 haplotypes found, 15 were ob.ained from Guinea Savanna, 7 from Forest and 13 from Coastal Savanna. Haplotype diversities were 0.978, 0.853 and 0.875 respectively for Guinea Savanna, Forest and Coastal Savanna zones. Analysis of molecular variance (AMOVA) revealed significant differentiation b.tween Forest and Savanna populations (FST = 0.14, p 0.05). Network analysis indicated two clusters, one of which consisted of only Savanna haplotypes. Population neutrality tests showed that Forest and Coastal Savanna populations had b.en stab.e while the Guinea Savanna zone population had undergone an expansion (Fu’s FS = ‐7.132,

关键词： Agro-Ecological Zones Rodent D-Loop Genetic Variation Thryonomys swinderianus

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Evaluation of genetic diversity and conservation priorities for Egyptian chickens

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Open Journal of Animal Sciences 2012年第3期2卷 183-190页

作者： Sherif Ramadan boniface b. kayang Eiji Inoue Keijiro Nirasawa Hiroshi Hayakawa Shin’ichi Ito Miho Inoue-Murayama Animal b.eeding and Reproduction Research Team National Institute of Livestock and Grassland Science Tsukuba Japan Department of Animal Science College of Agriculture and Consumer Sciences University of Ghana Legon Ghana Faculty of Applied b.ological Sciences Gifu University Gifu Japan Graduate School of Science Kyoto University Kyoto Japan Poultry Research Department Gifu Prefectural Livestock Research Institute Seki Japan Wildlife Research Center of Kyoto University Kyoto Japan

In this study, 21 microsatellite markers were used to genotype 196 Egyptian local chickens ob.ained from Fayoumi (n = 35), Dandarawy (n = 30), b.ladi (n = 29), Sinai (n = 30), El-Salam (n = 36), and Golden Montazah (n = 36) strains. The results were compared to two pure commercial chicken populations reared in Japan-White Leghorn (n = 42) and Rhode Island Red (n = 43). A total of 162 alleles were ob.erved, with an average of 7.7 alleles per locus. The average expected heterozygosity for the Egyptian chickens was 0.595. The closest pairwise Nei’s genetic distance was recorded b.tween Sinai and Golden Montazah (0.038) and the smallest pairwise FST value (0.006) was ob.erved b.tween b.ladi and Sinai. The most prob.b.e structure clustering of the eight studied populations was at K = 6. b.ladi, Sinai and Golden Montazah strains were clustered together forming admixed mosaic cluster. Dandarawy ranked firstly and contrib.ted the most to aggregate genetic diversity b.sed on two prioritization methods. The information resulting from this study may b. used as an initial guide to design further investigations for development of sustainab.e genetic improvement and conservation programs for the Egyptian chicken genetic resources.

关键词： Conservation Egyptian Chickens Genetic Diversity Microsatellite Population Structure

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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

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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

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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

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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

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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

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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

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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

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Effect of Al_(2)O_(3)on the Mechanical Properties of(b.(4)C+Al_(2)O_(3))/Al Neutron Ab.orb.ng Materials

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： J.X.Cai b.M.Shi N.Li Y.Liu Z.G.Zhang Y.N.Zan Q.Z.Wang b.L.Xiao Z.Y.Ma Shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Lab.ratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

b.(4)C/Al composites are widely utilized as neutron ab.orb.ng materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of b.(4)C/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted b. utilizing spheroid Al powder with varying diameters,thereb. investigating the impact of Al_(2)O_(3)content on the tensile properties of(b.(4)C+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain b.undaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhib.ted a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional b.(4)C/Al composites.

关键词： Al matrix composites Neutron ab.orb.ng materials (b.(4)C+Al_(2)O_(3))/Al composites High-temperature strength

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