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Soils in extraterrestrial space: Need for studies under microgravity

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Pedosphere 2024年第1期34卷 13-14页

作者： m.B.KIRKHAm Department of Agronomy Kansas State UniversityManhattan KS 66506USA

With the increased interest of plants in space, gravity cannot be ignored when studying soil-plant-water relations. Therefore, it is important to understand the water relations of soils under zero gravity in space or under reduced gravity on the moon or mars. This paper outlines the problems of moving water in soils under zero gravity or microgravity, as well as growing plants in these soils. It is suggested that microgravity experiments could be done on Earth using both soils and plants. Results from such experiments could be used to grow plants when mankind establishes bases on the moon and mars.

关键词： soils soil bases

4He monolayer on graphene: a quantum monte Carlo study

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Communications in Theoretical Physics 2024年第9期76卷 151-159页

作者： S Yu m Boninsegni Department of Physics University of Alberta

We revisit the problem of adsorption of a single4He layer on graphene, focusing on the commensurate(C1/3) crystalline phase, specifically on whether it may possess a nonzero superfluid response, and on the existence of superfluid phases, either（metastable） liquid or vacancy-doped crystalline. We make use of canonical quantum monte Carlo simulations at zero and finite temperature, based on a realistic microscopic model of the system. Our results confirm the absence of any superfluid response in the commensurate crystal, and that no thermodynamically stable uniform phase exists at lower coverage. No evidence of a possibly long-lived, metastable superfluid phase at C1/3coverage is found. Altogether, the results of ground-state projection methods and finite-temperature simulations are entirely consistent.

关键词： helium low-dimensional systems quantum monte Carlo superfluidity supersolids

Enhanced Wolf Pack Algorithm (EWPA) and Dense-kUNet Segmentation for Arterial Calcifications in mammograms

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Computers, materials & Continua 2024年第2期78卷 2207-2223页

作者： Afnan m.Alhassan College of Computing and Information Technology Shaqra UniversityShaqra11961Saudi Arabia

Breast Arterial Calcification(BAC)is a mammographic decision dissimilar to cancer and commonly observed in elderly *** identifying BAC could provide an expense,and be *** Deep Learning(DL)methods have been introduced for automatic BAC detection and quantification with increased ***,classification with deep learning had reached higher efficiency,but designing the structure of DL proved to be an extremely challenging task due to overfitting *** also is not able to capture the patterns and irregularities presented in the *** solve the overfitting problem,an optimal feature set has been formed by Enhanced Wolf Pack Algorithm(EWPA),and their irregularities are identified by Dense-kUNet *** this paper,Dense-kUNet for segmentation and optimal feature has been introduced for classification(severe,mild,light)that integrates DenseUNet and *** bound links exist among adjacent modules,allowing relatively rough data to be sent to the following component and assisting the system in finding higher *** major contribution of the work is to design the best features selected by Enhanced Wolf Pack Algorithm(EWPA),and modified Support Vector machine(mSVm)based learning for classification.k-Dense-UNet is introduced which combines the procedure of Dense-UNet and kU-Net for image *** bound associations occur among nearby sections,allowing relatively granular data to be sent to the next subsystem and benefiting the system in recognizing smaller *** proposed techniques and the performance are tested using several types of analysis techniques 826 filled digitized *** proposed method achieved the highest precision,recall,F-measure,and accuracy of 84.4333%,84.5333%,84.4833%,and 86.8667%when compared to other methods on the Digital Database for Screening mammography(DDSm).

关键词： Breast arterial calcification cardiovascular disease semantic segmentation transfer learning enhanced wolf pack algorithm and modified support vector machine

Effects of Andrade and Burgers rheologies on glacial isostatic adjustment modeling in Antarctica

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Geodesy and Geodynamics 2024年第5期15卷 429-440页

作者： Alexandre Boughanemi Anthony mémin UniversitéCôte d'Azur CNRSObservatoire de la Côte d'AzurIRDGéoazur250 rue Albert EinsteinSophia Antipolis 06560 ValbonneFrance

Variations in ice mass deform the Earth and modify its gravity field,a process known as Glacial Isostatic Adjustment(GIA).GIA in Antarctica remains poorly constrained due to the cumulative effect of past and present ice-mass changes,the unknown history of the past ice-mass change,and the uncertainties on the mechanical properties of the *** paper investigates the effect of using Andrade and Burgers viscoelastic rheologies,rather than the commonly used maxwell rheology,to model GIA-induced deformation in *** Love number and Green's function formalism are used to compute the radial surface displacements and the gravity changes induced by the past and present ice-mass *** consider an Earth model whose elastic properties and radial structure are averaged from the Preliminary Reference Earth model and two viscosity profiles to account for the recently published results on the present ice-mass *** the three rheological laws affects the temporal response of the Earth differently,leading to smaller discrepancies than those induced by the two viscosity *** differences are the largest between maxwell and Burgers rheologies during the 100-1000 years following the beginning of the surface-mass *** show that using the Andrade and Burgers rheologies allows the Earth to respond on decennial to centennial time scales,up to 10 m more than *** only the recent ice-mass changes,the deformation rates derived from Burgers and Andrade rheologies are several times larger than those estimated by maxwell rheology.

关键词： GIA Antarctica modeling Rheology Displacement Viscosity GNSS

Synergistic inhibition effect of poly(ethylene glycol) and cetyltrimethylammonium bromide on corrosion of Zn and Zn-Ni alloys for alkaline batteries

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Transactions of Nonferrous metals Society of China 2020年第1期30卷 259-274页

作者： Hany m.abd EL-LATEEF mahmoud ELROUBY Department of Chemistry Faculty of ScienceSohag UniversitySohag 82524Egypt Department of Chemistry College of ScienceKing Faisal UniversityP.O.Box 380 Al Hofuf 31982 Al-HassaSaudi Arabia

The synergistic inhibition effect of poly(ethylene glycol)-400(PEG-400)and cetyltrimethylammonium bromide(CTmAB)on the corrosion of Zn and Zn-Ni alloys in 8 mol/L KOH solution saturated with Zn O was observed by potentiodynamic anodic/cathodic polarization(PDP),and electrochemical impedance spectroscopy(EIS)*** electrochemical studies confirmed that there was a synergism between PEG-400 and CTmAB on corrosion inhibition of Zn and its *** inhibition efficiency of the mixed inhibitors,250 mg/L CTmAB+250 mg/L PEG-400,was found to be much higher than that of the single inhibitor,500 mg/L PEG-400 or 500 mg/L *** electron microscopic(SEm)investigations before and after the corrosion inhibition process emphasize the synergistic effect of the mixed ***,it was found that the addition of the investigated inhibitors to the alkaline solution enhanced the discharge and capacity of the alkaline battery *** obtained electrochemical data exhibited a good correlation with the computational one.

关键词： synergistic effect corrosion inhibition Zn-Ni alloy alkaline batteries

HCV Therapy Follow-up Fractionation (CTF2) by Intra-PBmC Nested RNA PCR Recognizes Early Virologic Response and Relapse

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Journal of Clinical and Translational Hepatology 2018年第2期6卷 147-154页

作者： mohamed Darwish Ahmed abd alla Saleh Ahmed Elibiary Ramy Hassan Elshaboury George Y.Wu Reham m.Dawood mostafa Kamel El Awady Tropical medicine Department Faculty of MedicineAl-Azhar UniversityCairoEgypt Department of Pharmacy Massachusetts General HospitalBostonMAUSA Department of medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterHartfordCTUSA Department of microbial Biotechnology National Research CenterCairoEgypt

Background and Aims:Sustained virologic response is evaluated by single-step reverse transcription(SRT)PCR as-say,which assesses hepatitis C virus(HCV)clearance from plasma but not from tissues such as peripheral blood mono-nuclear cells(PBmCs).Persistence of HCV RNA in PBmCs beyond end of treatment(EOT)is associated with *** goal was to measure intra-PBmC HCV RNA levels during oral antiviral therapy according to the HCV therapy follow-up fractionation(CTF2)***:Compen-sated chronic HCV patients(n=278 SRT-PCR positive)were scheduled to receive oral antiviral *** were followed-up by SRT and intra-PBmCs HCV RNA PCR at the end of the 2nd,6th,10th,14th,18th and 24th weeks to evaluate virus clearance from plasma and PBmCs,*** CTF2 protocol evaluated SRT and PBmC PCR status at each follow-up point for determining therapy continuation or inter-ruption to address cost ***:All patients tested negative by SRT PCR after therapy for 2 ***-cation of the CTF2 protocol revealed:a)increasing HCV clear-ance rate from 75.9%at the end of 10th week to 90.3%at the end of 24th week(pm plasma compared to PBmCs at each point of follow-up until the 18th week(pmination rates diagnosed by PBmC HCV RNA PCR(?)compared to PBmC HCV RNA PCR(+)from the 6th to 24th week of treatment(pme increase curve of combined plasma and PBmC HCV RNA determined negativity compared to the decline in positivity curves by PBmC PCR at the 6th-18th week compared to the 24th week(pment continuation;and e)solitary evaluation of EOT sustained HCV infection and relapses by PBmC HCV RNA(pmination of serum and tissue(PBmC)HCV infection by oral antiviral therapy can be achieved and evaluated during a cost-effective CTF2 pro-tocol application.

关键词： CTF2 protocol HCV PBmCs PCR Cost-effectiveness

Increasing the maximum Capacity Path in a Network and Its Application for Improving the Connection Between Two Routers

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Tsinghua Science and Technology 2024年第3期29卷 753-765页

作者： Adrian m.Deaconu Javad Tayyebi Department of mathematics and Computer Science Transilvania University of BrasovBrasov 500036Romania Department of Industrial Engineering Birjand University of TechnologyBirjand 000097Iran

Abstract:This paper addresses the problem of improving the optimal value of the maximum Capacity Path(mCP)through expansion in a flexible network,and minimizing the involved *** only condition applied to the cost functions is to be non-decreasing *** is a non-restrictive condition,reflecting the reality in practice,and is considered for the first time in the ***,the total cost of expansion is a combination of max-type cost(e.g.,for supervision)and sum-type cost(*** building infrastructures,price of materials,price of labor,etc.).For this purpose,two types of strategies are combined:(l)increasing the capacity of the existing arcs,and(l)adding potential new *** different problems are introduced and *** the problems have immediate applications in Internet routing *** first one is to extend the network,so that the capacity of an mcP in the modified network becomes equal to a prescribed value,therefore the cost of modifications is minimized.A strongly polynomial-time algorithm is deduced to solve this *** second problem is a network expansion under a budget constraint,so that the capacity of an mcP is maximized.A weakly polynomial-time algorithm is presented to deal with *** the special case when all the costs are linear,a meggido's parametric search technique is used to develop an algorithm for solving the problem in strongly polynomial *** new approach has a time complexity of O(n^(4)),which is better than the time complexity of O(n4 log(n)of the previously known method from literature.

关键词： maximum Capacity Path(mCP) network expansion Internet routing polynomial-time algorithms

Effect of Conductive Fillers on the Cyclic Stress-Strain and Nano-Scale Free Volume Properties of Silicone Rubber

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Chinese Journal of Polymer Science 2014年第5期32卷 558-567页

作者： m.H.abd-El Salam S.El-Gamal m.mohsen D.m.abd El-maqsoud Physics Department Faculty of Education Ain Shams University Physics Department Faculty of Science Ain Shams University

The effect of carbon black （CB） and graphite （G） powders on the macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-methylsiloxane）（PDmS） was studied through thermal and cyclic mechanical measurements, as well as with positron annihilation lifetime spectroscopy （PALS）. The melting temperature of the composites （Tm） and the endothermic enthalpy of melting （ΔHm） were estimated by differential scanning calorimetry （DSC）. Tm and the degree of crystallinity （χc） of PDmS composites were found to decrease with increasing the CB content. This can be explained due to the increase in physical cross-linking which results in a decrease in the crystallite thickness. Besides, χc was found to be dependent on the filler type. Cyclic stress-strain behavior of PDmS loaded with different contents of filler has been studied. mullins ratio （Rm） was found to be dependent on the filler type and content. It was found that, Rm increases with increasing the filler content due to the increase in physical cross-linking which results in a decrease in the size of free volume, as observed through a decrease of the o-Ps lifetime τ3 measured by PALS. moreover, the hysteresis in PDmS-CB composites was more pronounced than in PDmS-G composites. Furthermore, a correlation was established between the free volume Vf and the mechanical properties of PDmS composites containing different fillers. A negative correlation was observed between Vf and Rm.

关键词： Positron annihilation Positronium Free volume Si-rubber Composite Cyclic mechanical properties.

Finite Groups with Certain S-Permutable and GS-maximal Subgroups

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Algebra Colloquium 2020年第4期27卷 661-668页

作者： A.m.Elkholy m.H.abd-Ellatif Department of mathematics and Computer Science Faculty of Science Beni-Suef University62511 Beni-SuefEgypt

Let G be a finite group and H a subgroup of *** say that H is S-permutable in G if H permutes with every Sylow subgroup of G.A group G is called a generalized smooth group(GS-group)if[G/L]is totally smooth for every subgroup L of G of prime *** this paper,we investigate the structure of G under the assumption that each subgroup of prime order is S-permutable if the maximal subgroups of G are GS-groups.

关键词： smooth groups subgroup lattices S-permutability