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integrative Zoology 2024年第3期19卷 458-467页

作者： Roman sHARNUUD Eric i.AMEcA MOE Key Laboratory for Biodiversity science&Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijingChina climate change specialist Group Species Survival CommissionInternational Union for Conservation of NatureGlandSwitzerland

A signifi.ant research focus is placed on identifying animal species and areas at future risk to human-induced alterations of the environment and long-term changes in climatic ***,the extent to which exposure to extreme climatic events and intense human pressure can increase the risk of harmful impacts on species remains poorly *** on terrestrial mammals in china,one of the world’s megadiverse countries,we investigated patterns of contemporary exposure to floods and human pressures and determined their taxonomic representation and distribution across three major area-based conservation schemes,namely,national nature reserves(NNRs),priority areas for biodiversity conservation(PABcs),and key biodiversity areas(KBAs).Among the 440 species assessed with moderate or high exposure to floods,327(∼75%)also qualified as moderate or high in exposure to intense human *** species mainly belong to the orders chiroptera,Eulipotyphla,and ***,there were 305,311,and 311 species with moderate or high exposure to flood and intense human pressure represented across NNRs,PABcs,and KBAs,*** findings support the prioritization of KBAs for expansion of site-based protection efforts such as NNRs in china,considering threats to species from exposure to adverse effects from both extreme climate and human pressure.

关键词： conservation floods human pressure mammals taxonomy

Astrophysical s-factor and reaction rate for 15N(p,γ)16O within the modified potential cluster model

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chinese Physics c 2024年第4期48卷 130-145页

作者： s.B.Dubovichenko A.s.Tkachenko R.Ya.Kezerashvili N.A.Burkova B.M.Yeleusheva Fesenkov Astrophysical institute 050020 AlmatyKazakhstan New York city college of Technology City University of New YorkBrooklyn11201 New YorkUSA Graduate school and University center City University of New York10016 New YorkUSA al-Farabi Kazakh National University 050040 AlmatyKazakhstan

We study radiative p^(15)N capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(MPcM)with forbidden states,including low-lying *** investigation of the ^(15)N(p,γ0)^(16)O reaction includes the consideration of ^(3)s_(1) resonances due to E1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)N channel due to the ^(3)P_(1)→^(3)P_(0)M1 *** calculated the astrophysical low-energy s-factor,and the extrapolated s(0)turned out to be within 34.7−40.4 keV·*** important role of the asymptotic constant(Ac)for the ^(15)N(p,γ0)16O process with interfering ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances is elucidated.A comparison of our calculation for the s-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is *** reaction rate is calculated and compared with the existing *** has negligible dependence on the variation of Ac but shows a strong impact of the interference of ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances in reference to the cNO Gamow windows,especially at low *** estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from ***.c.85,065810(2012).The reaction rate enhancement due to the cascade transitions is observed from T_(9)>0.3 and reaches the maximum factor~1.3 at T_(9)=*** present the Gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)N(p,γ)^(13)O,^(13)N(p,γ)^(14)O,^(14)N(p,γ)^(15)O,and ^(15)N(p,γ)^(16)O obtained in the framework of the MPcM and provide the temperature windows,prevalence,and signifi.ance of each process.

关键词： low and astrophysical energies p^(15)N system thermonuclear reaction rate potential cluster model cNO-cycle

Microstructure， electrochemical， wear and corrosive wear performance of laser-based powder bed fusion(lpbf) and wrought biomedical Ti-6Al-4V alloys

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Transactions of Nonferrous Metals society of china 2024年

作者： A.G.Lekatou B.V.Efremenko V.Haoui V.G.Efremenko s.Emmanouilidou V.i.Zurnadzhy i.Petryshynets Yu.G.chabak i.i.sili Laboratory of Applied Metallurgy Department of Materials science and Engineering school of Engineering University of i.annina institute of Materials science and computing University research center of i.annina (URci) Pryazovskyi state Technical University Department of Physics institute of Materials research of slovak Academy of sciences

Wrought and laser powder bed fusion （LPBF） Ti-6Al-4V specimens were comparatively evaluated， with the objective to determine LPBF Ti-6-4’s suitability for biomedical applications. Testing included nanoindentation， cyclic polarization in simulated body fluid （sBF， 37 ℃ ）， and dry and sBF “Ball-on-Plate” sliding. Wrought Ti-6-4 exhibited a lamellar （α+β） microstructure， whereas LPBF displayed a fine-grained α'-martensite microstructure. LPBF Ti-6-4 demonstrated ～3% higher indentation modulus and ～32% higher hardness， while wrought Ti-6-4 showed ～8% higher plasticity. Both alloys exhibited low corrosion rates (10–5mA/cm2order) and true passivity (10–4mA/cm2order). No localized corrosion was observed in either alloy， except for occasional metastable pitting in the LPBF alloy. However， LPBF Ti-6-4 presented higher corrosion rate and passive current， ascribed to its martensitic structure. During dry sliding， LPBF Ti-6-4 exhibited ～14% lower volume loss compared to wrought Ti-6-4. sliding in sBF increased volume losses for both alloys， with wear resistances nearly equalized， as the advantage of LPBF Ti-6-4 decreased due to more intensive wear-accelerated corrosion induced by the stressed martensite. Overall， the results demonstrate the suitability of LPBF Ti-6Al-4V for biomedical uses.

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A modular microfluidic platform to study how fluid shear stress alters estrogen receptor phenotype in ER+breast cancer cells

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Microsystems & Nanoengineering 2024年第1期10卷 287-299页

作者： Braulio Andrés Ortega Quesada Jonathan cuccia Rachael coates Blake Nassar Ethan Littlefield Elizabeth c.Martin Adam T.Melvin cain Department of chemical Engineering Louisiana State UniversityBaton RougeLA 70803USA Department of chemical and Biological Engineering Clemson UniversityClemsonSC 29634USA Biological and Agricultural Engineering Louisiana State UniversityBaton RougeLA 70803USA Department Medicine Section Hematology and Medical OncologyTulane UniversityNew OrleansLA 70118USA

Metastatic breast cancer leads to poor prognoses and worse outcomes in patients due to its invasive behavior and poor response to *** is still unclear what biophysical and biochemical factors drive this more aggressive phenotype in metastatic cancer;however recent studies have suggested that exposure to fluid shear stress in the vasculature could cause *** this study a modular microfluidic platform capable of mimicking the magnitude of fluid shear stress(Fss)found in human vasculature was designed and *** device provides a platform to evaluate the effects of Fss on McF-7 cell line,an estrogen receptor positive(ER+)breast cancer cell line,during circulation in the *** of the effects of Fss on McF-7 cells was carried out utilizing two approaches:single cell analysis and bulk *** single cell analysis,cells were trapped in a microarray after exiting the serpentine channel and followed by immunostaining on the device(on-chip).Bulk analysis was performed after cells were collected in a microtube at the outlet of the microfluidic serpentine channel for western blotting(off-chip).it was found that cells exposed to an Fss magnitude of 10 dyn/cm^(2) with a residence time of 60 s enhanced expression of the proliferation marker Ki67 in the McF-7 cell line at a single cell *** understand possible mechanisms for enhanced Ki67 expression,on-chip and off-chip analyses were performed for pro-growth and survival pathways ERK,AKT,and JAK/*** demonstrated that after shearing the cells phosphorylation of p-AKT,p-mTOR,and p-sTAT3 were ***,there was no change in p-ERK1/*** is a mediator of ER rapid signaling,analysis of phosphorylated ERαwas carried out and no signifi.ant differences between sheared and non-sheared populations were *** together these results demonstrate that Fss can increase phosphorylation of proteins associated with a more aggressive phenotype in circulating cancer *** findin

关键词： fluid breast estrogen

The ccD instrument background of the sMiLE sXi

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.W.J.Hubbard O.Hetherington D.J.Hall T.W.Buggey s.Parsons T.Arnold A.Holland c.Pagani s.sembay centre for Electronic imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The EsA and cAs sMiLE mission orbit is highly elliptical and will pass through multiple radiation *** soft X-ray imager(sXi)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the ccDs(charge-coupled Devices)that form the focal plane array of the sXi were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic cosmic Rays(GcRs).it was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GcRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

The autophagy protein Atg9 functions in glia and contributes to parkinsonian symptoms in a Drosophila model of Parkinson’s disease

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Neural Regeneration research 2024年第5期19卷 1150-1155页

作者： shuanglong Yi Linfang Wang Margaret s.Ho shiping Zhang school of Life science and Technology ShanghaiTech UniversityShanghaiChina college of Life sciences University of Chinese Academy of SciencesBeijingChina

Parkinson’s disease is a progressive neurodegenerative disease characterized by motor deficits,dopaminergic neuron loss,and brain accumulation ofα-synuclein aggregates called Lewy *** in protein degradation pathways,such as autophagy,has been demonstrated in neurons as a critical mechanism for eliminating protein aggregates in Parkinson’s ***,it is less well understood how protein aggregates are eliminated in glia,the other cell type in the *** the present study,we show that autophagy-related gene 9(Atg9),the only transmembrane protein in the autophagy machinery,is highly expressed in Drosophila glia from adult *** from immunostaining and live cell imaging analysis reveal that a portion of Atg9 localizes to the trans-Golgi network,autophagosomes,and lysosomes in ***9 is persistently in contact with these *** glial atg9 reduces the number of omegasomes and autophagosomes,and impairs autophagic substrate *** suggests that glial Atg9 participates in the early steps of autophagy,and hence the control of autophagic ***,loss of glial atg9 induces parkinsonian symptoms in Drosophila including progressive loss of dopaminergic neurons,locomotion deficits,and glial *** findings identify a functional role of Atg9 in glial autophagy and establish a potential link between glial autophagy and Parkinson’s *** results may provide new insights on the underlying mechanism of Parkinson’s disease.

关键词： Atg9 autophagy glia Parkinson’s disease

Determi.ants and Outcomes of Pregnancies among Booked versus Unbooked Patients in a Tertiary Hospital south East, Nigeria

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Open Journal of Obstetrics and Gynecology 2024年第1期14卷 144-161页

作者： chijioke s. Anyigor-Ogah John O. Egede chijioke O. Ogeh chika c. Agunanne Alphosus i. Ozioko chinyere c. Duru Department of Family Medicine Alex Ekwueme Federal University Teaching Hospital Abakaliki Ebonyi State Nigeria Department of Obstetrics and Gynaecology Alex Ekwueme Federal University Teaching Hospital Abakaliki Ebonyi State Nigeria Department of Paediatrics Alex Ekwueme Federal University Teaching Hospital Abakaliki Ebonyi State Nigeria

Background: inadequate antenatal care, both in coverage and standard, has been linked with poor pregnancy outcomes. in a resource poor setting, home delivery is considered very cheap, but the possible outcome of such pregnancies has been a subject of interest. This study evaluated the association of booking status with pregnancy outcomes. Objectives: To examine the factors that influence booking and impact of the booking status on pregnancy outcomes. Methods: This was a hospital-based prospective cohort study of 240 (120 booked and 120 un-booked) pregnant mothers selected through systematic random sampling. The study was carried out at the Department of Obstetrics and Gynaecology, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Nigeria. chi-square test, t-test and logistic regression were used for analysis. results: The mean age of the partici.ants was 30.39 ± 5.05 years and 29.05 ± 6.36 years respectively for the booked and unbooked. Marital status (OR = 6.35, 95% ci = 1.24 - 32.59), educational status (OR = 36.40, 95% ci = 5.26-152.83), place of residence (OR = 0.15, 95% ci = 0.06 - 0.41), partner’s support (OR = 0.05, 95% ci = 0.01 - 0.37), family support (OR = 0.03, 95% ci = 0.01 - 0.13), mode of delivery (OR = 0.23, 95% ci = 0.12 - 0.46), APGAR score in first minute (OR = 6.02, 95% ci = 2.45 - 14.83) and NBicU admission (OR = 3.75, 95% ci = 1.67 - 8.43) were associated with booked status. However, being unmarried, nulliparity/grandmultiparity, low level of education, blue colar jobs, low income, rural dwelling and poor partner and poor family support were associated with the unbooked. The booked parturients had a better perinatal outcome compared the unbooked. conclusion/Recommendation: There was high prevalence of operative deliveries, perinatal morbidity and mortality among the unbooked mothers. Girl child education, employment and poverty alleviation would improve antenatal care utilization.

关键词： socio-Demographic characteristics Booking status Antenatal Delivery

change in Grain-size composition of Lignite under cyclic Freezing-Thawing and Wetting-Drying

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Natural resources 2024年第1期15卷 17-27页

作者： Natalia s. Batugina Vladislav i. Fedorov chersky institute of Mining of the North siberian Branch Russian Academy of sciences Yakutsk Russia

The paper presents the change in grain-size composition of lignite under cyclic freezing-thawing (FTc) and wetting-drying (WDc). The article shows that in the spring and autumn periods the lignites can be subjected to repeated freezing-thawing and wetting-drying, which determines the possibility of changing their grain-size composition and structure. Experimental studies in laboratory conditions on the influence of cyclic freezing-thawing (FTc) and wetting-drying (WDc) on the quality indicators of lignites have been carried out, their granulometric (fractional) composition has been studied. Freezing-thawing cycle conditions are as follows (FTc): minimum exposure temperature: -20°c;maximum: +5°c;relative humidity: 30%;number of processing cycles: 3. Wetting-drying cycles are as follows (WDc): drying temperatures are +20, +40, +60, +80°c, drying time 90 minutes, the coals are further subjected to rain (soaking) for a period of water saturation to humidity of 30% - 40% and dry again. The number of wetting-drying cycles is 3 times. The tests have revealed the destructive effects of FTc and WDc on the samples of lower metamorphic grade coal, and the cycles of wet-dry lead to the much higher yield of fine sizes (-6+0;-13+0 mm) than the cycles of freeze-thaw. Furthermore, it is found that the increase in the yield of fines depends on the heating temperature: coal disintegration proceeds more intensively at a higher temperature of drying.

关键词： Lignite Freezing-Thawing cycle Wetting-Drying cycle Grain size composition Dust coal storage Loss Quality

A Dimensional Reduction Approach Based on Essential constraints in Linear Programming

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Ameri.an Journal of Operations research 2024年第1期14卷 1-31页

作者： Eirini i. Nikolopoulou George s. Androulakis Department of Mathematics University of Patras Patras Greece Department of Business Administration University of Patras Patras Greece

This paper presents a new dimension reduction strategy for medium and large-scale linear programming problems. The proposed method uses a subset of the original constraints and combines two algorithms: the weighted average and the cosine simplex algorithm. The first approach identifies binding constraints by using the weighted average of each constraint, whereas the second algorithm is based on the cosine similarity between the vector of the objective function and the constraints. These two approaches are complementary, and when used together, they locate the essential subset of initial constraints required for solving medium and large-scale linear programming problems. After reducing the dimension of the linear programming problem using the subset of the essential constraints, the solution method can be chosen from any suitable method for linear programming. The proposed approach was applied to a set of well-known benchmarks as well as more than 2000 random medium and large-scale linear programming problems. The results are promising, indicating that the new approach contributes to the reduction of both the size of the problems and the total number of iterations required. A tree-based classification model also confirmed the need for combining the two approaches. A detailed numerical example, the general numerical results, and the statistical analysis for the decision tree procedure are presented.

关键词： Linear Programming Binding constraints Dimension Reduction cosine similarity Decision Analysis Decision Trees

sANc Monte carlo programs for small-angle Bhabha scattering

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chinese Physics c 2024年第4期48卷 14-19页

作者： A.B.Arbuzov s.G.Bondarenko i.R.Boyko L.V.Kalinovskaya A.A.Kampf R.R.sadykov V.L.Yermolchyk Bogoliubov Laboratory of Theoretical Physics JINRDubna141980 Russia Dzhelepov Laboratory of Nuclear Problems JINRDubna141980 Russia Dubna state University Dubna141982 Russia

Luminosity monitoring at e^(+)e^(−)colliders was investigated using sANc Monte carlo event generator RenesANce and integrator McsANc for simulation of Bhabha scattering at low *** are presented for center-of-mass energies of the Z boson resonance and at 240 GeV for the conditions of typical luminosity *** is shown that bremsstrahlung events with extremely low electron scattering angles are relevant to match the precision tags of future electron-positron colliders.

关键词： luminosity Bhabha scattering QED Monte carlo simulation