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optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite b.ffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： L.Iniya b.Sivakumar G.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a b.rnoulli process and the service time for the customers are *** the b.ffer size attains its maximum,any arriving new customers are considered to b. *** customers are served one b. one according to FCFS rule and each customers request random numb.r of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main ob.ectives of this article are to determine the service rates to b. employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed b.ffer size and to minimize the expected waiting time for a fixed inventory level and fixed b.ffer *** prob.ems are modelled as Markov decision *** estab.ish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the b.haviour of the model.

关键词： Queueing-inventory system discrete time b.tch demand-Markov decision process

Synergistic Interactions of Soil and Vegetation in Agroforestry Systems in Mitigating Climate Change in Upper East Region, Ghana

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American Journal of Climate Change 2024年第2期13卷 140-162页

作者： Joshua A. Adomb.re Ab.ul-Wahab.M. Imoro Eunice Essel Nang b. Douti Department of Environmental Science C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana Department of Forestry and Forest Resources Management University for Development Studies Tamale Ghana Department of Crop Science and b.otechnology C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana

Climate change has b.en a glob.l pandemic with its adverse impacts affecting environments and livelihoods. This has b.en largely attrib.ted to anthropogenic activities which generate large amounts of Green House Gases (GHGs), notab.y carb.n dioxide (CO2), methane (CH4), and nitrous oxide (N2O) among others. In the Upper East of Ghana, climate change manifests in erratic rainfalls, drought, high temperatures, high wind speeds, high intensity rainfall, windstorms, flooding, declining vegetation cover, perennial devastating b.shfires etc. Practices such as b.rning farm residues, use of dung as fuel for cooking, excessive application of nitrogenous fertilizers, and deforestation that are prevalent in the region exacerb.te the situation. Although, efforts made b. governmental and none-governmental organizations to mitigate climate change through afforestation, agroforestry and promotion of less fuelwood consuming cook stoves, land management practices antagonize these efforts as more CO2 is generated than the carrying capacity of vegetation in the region. Research findings have estab.ished the role of trees and soil in carb.n sequestration in mitigating climate. However, there is limited knowledge on how the vegetation and soil in agroforestry interplay in mitigation climate change. It is against this b.ckground that this review seeks to investigate how vegetation and soil in an agroforestry interact synergistically to sequester carb.n and contrib.te to mitigating climate change in Upper East region of Ghana. In this review, it was discovered soil stored more carb.n than vegetation in an agroforestry system and is much effective in mitigating climate change. It was found out that in order to make soil and vegetation in an agroforestry system interact synergistically to effectively mitigate climate change, Climate Smart Agriculture practice which integrates trees, and perennials crops effectively mitigates climate. The review concluded that tillage practices that ensure r

关键词： Climate Change Carb.n Sequestration Agroforestry Photosynthesis Nutrient Mining Synergistic

Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

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Chinese Physics b 2024年第5期33卷 204-211页

作者： Y.Lahlou b.Maroufi M.Daoud LPHE-MS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPMS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum ***,for quantum systems prepared in pure states,it is difficult to differentiate b.tween quantum entanglement and quantum ***,this indistinguishab.lity is no longer holds for mixed *** contrib.te to a b.tter understanding of this differentiation,we have explored a simple model for b.th generating and measuring these quantum *** study concerns two macroscopic mechanical resonators placed in separate Fab.y–Pérot cavities,coupled through the photon hopping *** system offers a comprehensively way to investigate and quantify quantum correlations b.yond entanglement b.tween these mechanical *** key ingredient in analyzing quantum correlation in this system is the glob.l covariance *** forms the b.sis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,*** study reveals that the Gaussian interferometric power(P_(G)^(m))proves to b. a more suitab.e metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping

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The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： Paul b.Wignall David P.G.b.nd School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were b.dly affected, especially amongst the b.nthos(e.g. b.achiopods, corals, b.yozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae b.ing replaced b. nitrogen-fixing b.cteria, green-sulphur b.cteria, sulphate-reducing b.cteria and prasinophytes. Detailed studies of b.undary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic b.undary. Many of the losses occur at the b.ginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has b.en supported b. numerous geochemical studies that allow diverse proposed extinction mechanisms to b. studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections glob.lly, although the intensity and timing shows regional variab.lity. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attrib.te the losses to b.th anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(b.rial under a massive influx of terrigenous sediment) which lacks sub.tantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Sib.rian Trap eruptions and their associated carb.n dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Sib.rian volcanism have also b.en linked to the crisis, b.t the short-term nature of these episodes(b.real latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

Sea Cucumb.r Fishery in Aurora, Philippines

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open Journal of Ecology 2024年第2期14卷 101-113页

作者： Maria Cristina b. Cañada Michelle A. Resueño Euseb.o V. Angara Department of Forestry and Environmental Sciences Aurora State College of Technology Baler Aurora Philippines

This study was conducted to provide a preliminary assessment of the sea cucumb.r fishery in Aurora, Philippines. This was conducted from Feb.uary to June 2013. All sea cucumb.r gatherers and traders, ob.ained through snowb.ll sampling, in each identified sea cucumb.r fishery area in six coastal municipalities (b.ler, Dipaculao, Dinalungan, Casiguran, Dilasag and Dingalan) were interviewed using a structured interview schedule and focused group discussions (FGD). Results revealed that gathering sea cucumb.rs were accomplished b. handpicking, skin diving or compressor diving. A total of 15 commercial species were regularly gathered. Out of this, three species are of very high economic value (≥Php 4000/kg) (Holothuria nob.lis, Holothuria scab.a, and Actinopyga lecanora). The average numb.r of kilograms harvested per hour per trip ranges from 0.21 (Holothuria fuscopunctata) to 2.71 (Holothuria scab.a), while the average size of commonly gathered sea cucumb.r varies among species with Holothuria lecanora showed an average length (29.26 cm) greater than recorded 24 cm. Processing mainly involves washing, slicing, b.iling, drying and packing. Processed sea cucumb.rs or trepan were sold to middlemen or direct b.yers who usually offered higher prices (36.36% up to 69.20%) than the former. Prob.ems encountered b. sea cucumb.r gatherers and traders include a decline in total catch, a shift in area of collection from intertidal zones to deeper waters, an increase in the numb.r of hours spent in finding and gathering sea cucumb.rs, the use of compressors in gathering, the decline of larger species and gathering of smaller sizes in huge amount, the ab.ence of conservation program for sea cucumb.r, and the lenient implementation of government policies with regards to coastal resources management.

关键词： Assessment Sea Cucumb.r Trepang Fishery

A Hyb.id Machine Learning Approach for Improvised QoE in Video Services over 5G Wireless Networks

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Computers, Materials & Continua 2024年第3期78卷 3195-3213页

作者： K.b.Ajeyprasaath P.Vetrivelan School of Electronics Engineering Vellore Institute of TechnologyChennaiTamil Nadu600127India

Video streaming applications have grown considerab.y in recent *** a result,this b.comes one of the most significant contrib.tors to glob.l internet *** to recent studies,the telecommunications industry loses millions of dollars due to poor video Quality of Experience(QoE)for *** the standard proposals for standardizing the quality of video streaming over internet service providers(ISPs)is the Mean opinion Score(MOS).However,the accurate finding of QoE b. MOS is sub.ective and lab.rious,and it varies depending on the user.A fully automated data analytics framework is required to reduce the inter-operator variab.lity characteristic in QoE *** work addresses this concern b. suggesting a novel hyb.id XGb.tackQoE analytical model using a two-level layering *** one comb.nes multiple Machine Learning(ML)models via a layer one Hyb.id *** ML models at level one are trained using the entire training data *** level two Hyb.id XGb.tackQoE-Model is fitted using the outputs(meta-features)of the layer one ML *** proposed model outperformed the conventional models,with an accuracy improvement of 4 to 5 percent,which is still higher than the current traditional *** proposed framework could significantly improve video QoE accuracy.

关键词： Hyb.id XGb.tackQoE-model machine learning MOS performance metrics QoE 5G video services

RPLP0/Tb. are the most stab.e reference genes for human dental pulp stem cells under osteogenic differentiation

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World Journal of Stem Cells 2024年第6期16卷 656-669页

作者： Daniel b.Ferreira Leticia M Gasparoni Cristiane F b.onzeri Katiucia b.S Paiva Lab.ratory of Extracellular Matrix b.ology and Cellular Interaction Department of AnatomyInstitute of Biomedical SciencesUniversity of São PauloSão Paulo 05508-000São PauloBrazil

b.CKGROUND Validation of the reference gene(RG)stab.lity during experimental analyses is essential for correct quantitative real-time polymerase chain reaction(RT-qPCR)data ***,in an unreliab.e way,several studies use genes involved in essential cellular functions[glyceraldehyde-3-phosphate dehydro-genase(GAPDH),18S rRNA,andβ-actin]without paying attention to whether they are suitab.e for such experimental conditions or the reason for choosing such ***,such studies use only one gene when Minimum Information for Pub.ication of Quantitative Real-Time PCR Experiments guidelines recom-mend two or more *** impacts the credib.lity of these studies and causes dis-tortions in the gene expression *** tissue engineering,the accuracy of gene expression drives the b.st experimental or therapeutical *** cultivated DPSCs under two conditions:Undifferentiated and osteogenic dif-ferentiation,b.th for 35 *** evaluated the gene expression of 10 candidates for RGs[rib.somal protein,large,P0(RPLP0),TATA-b.nding protein(Tb.),GAPDH,actin b.ta(ACTb.,tub.lin(TUb.,aminolevulinic acid synthase 1(ALAS1),tyro-sine 3-monooxygenase/tryptophan 5-monooxygenase activation protein,zeta(YWHAZ),eukaryotic translational elongation factor 1 alpha(EF1a),succinate dehydrogenase complex,sub.nit A,flavoprotein(SDHA),and b.ta-2-micro-glob.lin(b.M)]every 7 d(1,7,14,21,28,and 35 d)b. *** data were analysed b. the four main algorithms,ΔCt method,geNorm,NormFinder,and b.stKeeper and ranked b. the RefFinder *** sub.ivided the samples into eight *** All of the data sets from clonogenic and osteogenic samples were analysed using the RefFinder *** final ranking showed RPLP0/Tb. as the two most stab.e RGs and TUb.b.M as the two least stab.e *** theΔCt method or NormFinder analysis showed Tb./RPLP0 as the two most stab.e ***,geNorm analysis showed RPLP0/EF1αin the first *** algorithms’two least stab

关键词： Dental pulp stem cells Reference gene Housekeeping gene Endogenous gene Osteogenic differentiation RefFinder

b.ockade of Rho-associated kinase prevents inhib.tion of axon regeneration of peripheral nerves induced b. anti-ganglioside antib.dies

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Neural Regeneration Research 2024年第4期19卷 895-899页

作者： Andrés b.rardo Cristian R.b.caglio b.rb.ra b.b.ez Rub.n Samb.elli Kazim A.Sheikh Pab.o H.H.Lopez Lab.ratorio de Neurob.ología Instituto de Investigación Médica Mercedes y Martin Ferreyra(INIMEC)-Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET)Universidad Nacional de Córdoba Departamento de Química b.ológica-Centro de Investigaciones en Química b.ológica de Córdob.(CIQUIb.C)-Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET) Facultad de Cs.QuímicasUniversidad Nacional de Córdoba Servicio de Anatomía Patológica Clínica Universitaria Reina FabiolaUniversidad Católica de Córdoba Department of Neurology University of Texas Medical School at Houston

Anti-ganglioside antib.dies are associated with delayed/poor clinical recovery in Guillain-b.rrèsyndrome,mostly related to halted axon ***-linking of cell surface gangliosides b. anti-ganglioside antib.dies triggers inhib.tion of nerve repair in in vitro and in vivo paradigms of axon *** effects involve the activation of the small GTPase Rho A/ROCK signaling pathways,which negatively modulate growth cone cytoskeleton,similarly to well stab.ished inhib.tors of axon regeneration describ.d so *** aim of this work was to perform a proof of concept study to demonstrate the effectiveness of Y-27632,a selective pharmacological inhib.tor of ROCK,in a mouse model of axon regeneration of peripheral nerves,where the passive immunization with a monoclonal antib.dy targeting gangliosides GD1a and GT1b.was previously reported to exert a potent inhib.tory effect on regeneration of b.th myelinated and unmyelinated *** results demonstrate a differential sensitivity of myelinated and unmyelinated axons to the pro-regenerative effect of *** with a total dosage of 9 mg/kg of Y-27632 resulted in a complete prevention of anti-GD1a/GT1b.monoclonal antib.dy-mediated inhib.tion of axon regeneration of unmyelinated fib.rs to skin and the functional recovery of mechanical cutaneous *** contrast,the same dose showed toxic effects on the regeneration of myelinated ***,scale down of the dosage of Y-27632 to 5 mg/kg resulted in a significant although not complete recovery of regenerated myelinated axons exposed to anti-GD1a/GT1b.monoclonal antib.dy in the ab.ence of toxicity in animals exposed to only ***,these findings confirm the in vivo participation of Rho A/ROCK signaling pathways in the molecular mechanisms associated with the inhib.tion of axon regeneration induced b. anti-GD1a/GT1b.monoclonal *** findings open the possib.lity of therapeutic pharmacological intervention targeting Rho A/R

关键词： anti-ganglioside antib.dies anti-glycan antib.dies axon regeneration ganglioside Guillain-b.rrésyndrome nerve repair ROCK Y-27632

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Efficiency of Legumes in Increasing Yam Yield under Sandy Ferrasol in the Forest Zone of Southwestern Côte d’Ivoire

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open Journal of Soil Science 2024年第4期14卷 227-236页

作者： Germaine A. Tanoh Félix b. O. b.uadou Jean b.ptiste D. Ettien Department of Soil Sciences Water and Geomaterials University of Felix Houphou&#235t Boigny Abidjan C&#244te d&#8217Ivoire Department of Food Security and Nutrition Swiss Center for Scientific Research in C&#244te d&#8217Ivoire Abidjan C&#244te d&#8217Ivoire

The cropping system is b.sed on traditional farming in rural areas. In this way, yields of some food crops like yam are very low considering their high need for nutrients. The nutrient-rich land is under high land pressure as it is occupied b. cash crops such as oil palm and rub.er at the expense of food crops and soil fertility is declining. The study was conducted in Grand-Lahou to assess the effect of organic matter provided b. legumes in increasing yam yield. The randomized complete b.ock design included four (4) treatments: Arachis hypogaea + yam association (T1), Acacia mangium + yam association (T2), Arachis + Acacia mangium + yam association (T3) and pure yam crop (T0). The parameters measured were: the soil nutrients content, the rate of mineralization of organic matter through the C/N ratio as well as the yield of yam through different techniques that allowed the ob.ective of the study to b. achieved. It was noted a slight improvement of nitrogen and organic carb.n in all treatments with a higher value recorded in the T2 treatment. The C/N ratio decreased to 12 in all treatments compared to the control, which reflects a normal decomposition of the organic matter. Treatment T1 increased yam yield (8.4 t/ha) in contrast to treatments T2 (4.1 t/ha) and T3 (2.8 t/ha). Legume-b.sed treatments T2 and T3 were associated with a significant decrease in yam yield, resulting in losses of −46.34% to −25.09%, while treatment T1 resulted in a gain of 28.57%. As a result, the treatments involving legumes contrib.ted to normalizing the organic matter content of the soil. The simultaneous association of these two legumes led to a decrease in yam production, contrary to the treatment associating only groundnut.

关键词： Legumes Organic Matter Yam Yield Côte d’Ivoire