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Effect of site and elevation on wood density and shrinkage and their relationships in Carpinus betulus

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Forestry Studies in China 2012年第3期14卷 229-234页

作者： majid kiaei Department of Wood Science and Paper Technology Chaloos BranchIslamic Azad UniversityChaloos46615/397Iran

This study examined the effect of site and elevation on the oven-dry density and volumetric shrinkage of hornbeam （Carpinus betulus） wood. For this purpose, 45 normal hornbeam trees from three different sites （Mazandaran, Guilan and Golestan） at three elevations, 300 m （low elevation）, 700 m （intermediate elevation） and 1100 m （high elevation） from natural forest in northern Iran were selected. Disks were cut at breast height from mature wood and test samples were prepared to determine physical proper- ties, i.e., wood density and volumetric shrinkage. The results show that there are significant differences between site and elevation on these physical properties of wood. The interaction effects between site ~ elevation on wood density and volumetric shrinkage were also statistically significant. At any fixed site, wood density and volumetric shrinkage increased with elevation. As well, their values at Guilan were higher than those at the other two sites. The relationship between wood density and volumetric shrinkage was deter- mined by simple regression equations. Strong, positive relationships between wood density and volumetric shrinkage at each site were found. Again, these were stronger at the Guilan site than at the other two sites. Given a fixed site, the correlation at high eleva- tion was stronger than at the other two elevations.

关键词： Carpinus betulus site elevation wood density volumetric shrinkage

Energy evolution and structural health monitoring of coal under different failure modes:An experimental study

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 917-928页

作者： Yarong Xue Xueqiu He Dazhao Song Zhenlei Li majid Khan Taoping Zhong Fei Yang School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Zhong-an Academy of Safety Engineering Beijing 100083China

Structural instability in underground engineering,especially in coal-rock structures,poses significant safety risks.Thus,the development of an accurate monitoring method for the health of coal-rock bodies is crucial.The focus of this work is on understanding energy evolution patterns in coal-rock bodies under complex conditions by using shear,splitting,and uniaxial compression tests.We examine the changes in energy parameters during various loading stages and the effects of various failure modes,resulting in an innovative energy dissipation-based health evaluation technique for coal.Key results show that coal bodies go through transitions between strain hardening and softening mechanisms during loading,indicated by fluctuations in elastic energy and dissipation energy density.For tensile failure,the energy profile of coal shows a pattern of “high dissipation and low accumulation” before peak stress.On the other hand,shear failure is described by “high accumulation and low dissipation” in energy trends.Different failure modes correlate with an accelerated increase in the dissipation energy before destabilization,and a significant positive correlation is present between the energy dissipation rate and the stress state of the coal samples.A novel mathematical and statistical approach is developed,establishing a dissipation energy anomaly index,W,which categorizes the structural health of coal into different danger levels.This method provides a quantitative standard for early warning systems and is adaptable for monitoring structural health in complex underground engineering environments,contributing to the development of structural health monitoring technology.

关键词： energy dissipation structural health monitoring early warning coal-rock mechanics failure mode

Determination of fiber length and juvenile and mature wood zones in Acer velutinum Boiss.trees grown in Iran

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Forestry Studies in China 2012年第4期14卷 323-326页

作者： majid kiaei Reza BAKHSHI Samane VEYLAKI Department of Wood and Paper Science and Technology Chaloos BranchIslamic Azad University

In our investigation we studied fiber lengths and the transition age from juvenile to mature wood in Acer velutinum Boiss. For this purpose, samples from three normal maple trees at a Noshahr site in northern Iran were selected. Disks were cut at breast height. Test samples were taken along a radial direction from the pith to the bark, accounting for every ring during a 48-year period. We used the Franklin method to distinguish between fibers of juvenile and mature wood. The results show that the fiber length in- creased along the radial direction from the pith to the bark. The transition age between juvenile and mature wood was determined at the 14th annual ring from the pith.

关键词： Acer velutinum Boiss. transition age juvenile wood mature wood fiber length

应用欧拉-拉格朗日方法分析动脉粥样硬化性颈动脉血流的流-固相互作用

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Journal of Central South University 2024年第1期31卷 151-168页

作者： majid SIAVASHI Ava BINA Mojtaba SAYADNEJAD Borhan BEIGZADEH Applied Multi-Phase Fluid Dynamics Lab. School of Mechanical EngineeringIran University of Science and TechnologyTehranIran Biomechatronics and Cognitive Engineering Research Lab. School of Mechanical EngineeringIran University of Science and TechnologyTehranIran

本研究旨在模拟不同狭窄程度和脉搏率的颈动脉搏动血流。采用流-固耦合(FSI)和任意拉格朗日-欧拉(ALE)方法研究了不同狭窄程度、脉搏率和动脉壁性质对周围流体的影响。分别应用Carreau-Yasuda非牛顿超弹性模型和修正Mooney-Rivin超弹性... 详细信息

本研究旨在模拟不同狭窄程度和脉搏率的颈动脉搏动血流。采用流-固耦合(FSI)和任意拉格朗日-欧拉(ALE)方法研究了不同狭窄程度、脉搏率和动脉壁性质对周围流体的影响。分别应用Carreau-Yasuda非牛顿超弹性模型和修正Mooney-Rivin超弹性模型于具有非牛顿行为的血液和超弹性血管壁。结果得到血液的壁面径向位移、压力分布、轴向速度分布和壁面剪切应力。通过增加狭窄的严重程度,轴向速度、血压变化、最大壁面剪切应力和壁面径向位移均呈增长趋势。当脉率在狭窄程度为75%时,最大流量矩、壁面径向位移、压力、轴向速度和壁面剪应力的最大值均增大。此外,与弹性和刚性模型相比,将动脉壁视为超弹性模型,将其周围流体视为非牛顿和非定常,可以使模拟更加真实。在严重程度高达50%的狭窄中,红细胞受到轻微损害,而在严重程度为75%的狭窄中观察到溶血。通过改善动脉粥样硬化,弹性模量从500 k Pa提高到2 MPa,在60 bpm脉率和狭窄程度75%下,剪切应力最大值增长65%。与刚性和弹性动脉壁相比,动脉壁的超弹性模型导致较低的轴向速度、较低的血压、较低的剪切应力和较高的径向位移。

关键词：流-固耦合狭窄严重程度脉率变化超弹性的动脉动脉粥样硬化

Multiplicity dependence of the freezeout parameters in high energy hadron-hadron collisions

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Chinese Physics C 2024年第5期48卷 124-133页

作者： Muhammad Ajaz majid Shehzad Muhammad Waqas Haifa I.Alrebdi Mohammad Ayaz Ahmad Antalov Jagnandan Shawn Jagnandan Murad Badshah Jalal Hasan Baker Abdul Mosawir Quraishi Department of Physics Abdul Wali Khan University MardanMardan 23200Pakistan School of Mathematics Physics and Optoelectronic EngineeringHubei University of Automotive TechnologyShiyan 442002China Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of Mathematics Physics and StatisticsFaculty of Natural SciencesUniversity of Guyana101110 GeorgetownGuyananSouth America Department of Physics Faculty of ScienceUniversity of TabukTabukKingdom of Saudi Arabia Department of Electrical Engineering College of EngineeringQassim UniversityUnaizahSaudi Arabia

We examined the transverse momentum(pT)spectra of various identified particles,encompassing both light-flavored and strange hadrons(π++π−,K++K−,p+p¯,ϕ,K0s,Λ+Λ¯,Ξ−+Ξ¯+,andΩ−+Ω¯+),across different multiplicity classes in proton-proton collisions(p-p)at a center-of-mass energy of s√=7 TeV.Utilizing the Tsallis and Hagedorn models,parameters relevant to the bulk properties of nuclear matter were extracted.Both models exhibit good agreement with experimental data.In our analyses,we observed a consistent decrease in the effective temperature(T)for the Tsallis model and the kinetic or thermal freeze-out temperature(T0)for the Hagedorn model,as we transitioned from higher multiplicity(class-I)to lower multiplicity(class-X).This trend is attributed to the diminished energy transfer in higher multiplicity classes.Additionally,we observed that the transverse flow velocity(βT)experiences a decline from class-I to class-X.The normalization constant,which represents the multiplicity of produced particles,was observed to decrease as we moved toward higher multiplicity classes.While the effective and kinetic freeze-out temperatures,as well as the transverse flow velocity,show a mild dependency on multiplicity for lighter particles,this dependency becomes more pronounced for heavier particles.The multiplicity parameter for heavier particles was observed to be smaller than that of lighter particles,indicating a greater abundance of lighter hadrons compared to heavier ones.Various particle species were observed to undergo decoupling from the fireball at distinct temperatures:lighter particles exhibit lower temperatures,while heavier ones show higher temperatures,thereby supporting the concept of multiple freeze-out scenarios.Moreover,we identified a positive correlation between the kinetic freeze-out temperature and transverse flow velocity,a scenario where particles experience stronger collective motion at a higher freeze-out temperature.The reason for this positive correlation is that,as the multiplicity increases,more energy is

关键词： multiplicity dependence collective properties thermal energy

Malaysia-China Relations:Exemplary Model for ASEAN

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China Report ASEAN 2024年第6期9卷 48-51页

作者： Dato'Abdul majid Ahmad Khan Malaysia-China Friendship Association

Five Decades(1974-2024)of Harmonious and Mutually Beneficial Partnership Fifty years ago in May 1974,the second Prime Minister of Malaysia,Tun Abdul Razak,journeyed to Beijing,China,to start a new and strategic chapter in Malaysia-China relations.It was a visionary and courageous initiative by Malaysia that commenced resetting Malaysia's foreign policy towards non-alignment and building mutual trust with China.

关键词： Malaysia mutual policy

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The interplay mechanism between IDH mutation, MGMT-promoter methylation, and PRMT5 activity in the progression of grade 4 astrocytoma: unraveling the complex triad theory

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Oncology Research 2024年第6期32卷 1037-1045页

作者： MAHER KURDI ALAA ALKHOTANI ABDULRAHMAN SABBAGH EYAD FAIZO AHMED I.LARY AHMED K.BAMAGA majid ALMANSOURI BADR HAFIZ THAMER ALSHARIF SALEH BAEESA Department of Pathology Faculty of MedicineKing Abdulaziz UniversityRabighSaudi Arabia Department of Pathology College of MedicineUmm Al-Qura UniversityMakkahSaudi Arabia Department of Surgery Faculty of MedicineKing Abdulaziz UniversityJeddahSaudi Arabia Department of Surgery Faculty of MedicineUniversity of TabukTabukSaudi Arabia Section of Neurosurgery Department of SurgeryKing Abdulaziz Medical CityJeddahSaudi Arabia Department of Pediatrics Faculty of MedicineKing Abdulaziz UniversityJeddahSaudi Arabia Department of Clinical Biochemistry Faculty of MedicineKing Abdulaziz UniversityJeddahSaudi Arabia Department of Neurosciences King Faisal Specialist Hospital and Research CenterJeddahSaudi Arabia Department of Surgery King Abdulaziz Specialist HospitalTaifSaudi Arabia

Background:The dysregulation of Isocitrate dehydrogenase(IDH)and the subsequent production of 2-Hydroxyglutrate(2HG)may alter the expression of epigenetic proteins in Grade 4 astrocytoma.The interplay mechanism between IDH,O-6-methylguanine-DNA methyltransferase(MGMT)-promoter methylation,and protein methyltransferase proteins-5(PRMT5)activity,with tumor progression has never been described.Methods:A retrospective cohort of 34 patients with G4 astrocytoma is classified into IDH-mutant and IDH-wildtype tumors.Both groups were tested for MGMT-promoter methylation and PRMT5 through methylation-specific and gene expression PCR analysis.Inter-cohort statistical significance was evaluated.Results:Both IDH-mutant WHO grade 4 astrocytomas(n=22,64.7%)and IDH-wildtype glioblastomas(n=12,35.3%)had upregulated PRMT5 gene expression except in one case.Out of the 22 IDH-mutant tumors,10(45.5%)tumors showed MGMT-promoter methylation and 12(54.5%)tumors had unmethylated MGMT.All IDH-wildtype tumors had unmethylated MGMT.There was a statistically significant relationship between MGMT-promoter methylation and IDH in G4 astrocytoma(p-value=0.006).Statistically significant differences in progression-free survival(PFS)were also observed among all G4 astrocytomas that expressed PRMT5 and received either temozolomide(TMZ)or TMZ plus other chemotherapies,regardless of their IDH or MGMT-methylation status(p-value=0.0014).Specifically,IDH-mutant tumors that had upregulated PRMT5 activity and MGMT-promoter methylation,who received only TMZ,have exhibited longer PFS.Conclusions:The relationship between PRMT5,MGMT-promoter,and IDH is not tridirectional.However,accumulation of D2-hydroxyglutarate(2-HG),which partially activates 2-OG-dependent deoxygenase,may not affect their activities.In IDH-wildtype glioblastomas,the 2HG-2OG pathway is typically inactive,leading to PRMT5 upregulation.TMZ alone,compared to TMZ-plus,can increase PFS in upregulated PRMT5 tumors.Thus,using a PRMT5 inhibitor in G4 astrocytomas may help in tumor regression.

关键词： Grade 4 astrocytoma Glioblastoma Isocitrate dehydrogenase(IDH) O-6-methylguanine-DNA methyltransferase(MGMT) Protein methyltransferase proteins-5(PRMT5) Progression-free survival(PFS)

The effect of celastrol in combination with 5-fluorouracil on proliferation and apoptosis of gastric cancer cell lines

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Oncology Research 2024年第7期32卷 1231-1237页

作者： MOHAMMAD-TAGHI MORADI DHIYA ALTEMEMY majid ASADI-SAMANI PEGAH KHOSRAVIAN MARZIYEH SOLTANI LEILA HASHEMI AZADEH SAMIEI-SEFAT Medical Plants Research Center Basic Health Sciences InstituteShahrekord University of Medical SciencesShahrekordIran Department of Pharmaceutics College of PharmacyAl-Zahraa University for WomenKarbalaIraq Cellular and Molecular Research Center Basic Health Sciences InstituteShahrekord University of Medical SciencesShahrekordIran

Background:Despite the availability of chemotherapy drugs such as 5-ﬂuorouracil(5-FU),the treatment of some cancers such as gastric cancer remains challenging due to drug resistance and side effects.This study aimed to investigate the effect of celastrol in combination with the chemotherapy drug 5-FU on proliferation and induction of apoptosis in human gastric cancer cell lines(AGS and EPG85-257).Materials and Methods:In this in vitro study,AGS and EPG85-257 cells were treated with different concentrations of celastrol,5-FU,and their combination.Cell proliferation was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT)assay.The synergistic effect of 5-FU and celastrol was studied using Compusyn software.The DNA content at different phases of the cell cycle and apoptosis rate was measured usingﬂow cytometry.Results:Co-treatment with low concentrations(10%inhibitory concentration(IC10))of celastrol and 5-FU signiﬁcantly reduced IC50(p<0.05)so that 48 h after treatment,IC50 was calculated at 3.77 and 6.9μM for celastrol,20.7 and 11.6μM for 5-FU,and 5.03 and 4.57μM for their combination for AGS and EPG85-257 cells,respectively.The mean percentage of apoptosis for AGS cells treated with celastrol,5-FU,and their combination was obtained 23.9,41.2,and 61.9,and for EPG85-257 cells 5.65,46.9,and 55.7,respectively.In addition,the 5-FU and celastrol-5-FU combination induced cell cycle arrest in the synthesis phase.Conclusions:Although celastrol could decrease the concentration of 5-ﬂuorouracil that sufﬁced to suppress gastric cancer cells,additional studies are required to arrive at conclusive evidence on the anticancer effects of celastrol.

关键词： Gastric cancer Celastrol Terpenoid Cell cycle regulation Apoptosis Synergism

Long-term outcomes of titanium-nitride-oxide coated stents and drug-eluting stents in acute coronary syndrome:A systematic review and meta-analysis

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World Journal of Cardiology 2024年第5期16卷 293-305页

作者： Muhammad Ahmed Ali Fahim Afia Salman Hira Anas Khan Syed Muhammad Hasan Muskan FatimaBhojani Sarah Aslam Amna Zia Ul Haq Vishal Reddy Bejugam Beena Muntaha Nasir Wajiha Gul Abdul Moeed Abdelrahman S Abdalla Muhammad majid Muhammad Sohaib Asghar Md Al Hasibuzzaman Department of Internal Medicine Dow University of Health SciencesKarachi 74200Pakistan Department of Internal Medicine North Central Bronx HospitalBronxNY 10467United States Department of Urology Center for Academic MedicineStanford University School of MedicinePalo AltoCA 33872United States Department of Cardiovascular Imaging Cleveland ClinicClevelandOH 44195United States Division of Nephrology and Hypertension Mayo Clinic RochesterRochesterMN 55905United States Institute of Nutrition and Food Science University of DhakaDhaka 1000Bangladesh

BACKGROUND In severe cases of coronary artery disease,percutaneous coronary intervention provide promising results.The stent used could be a drug-eluting stent(DES)or a titanium-nitride-oxide coated stent(TiNOS).AIM To compare the 5-year effectiveness and safety of the two stent types.METHODS The following systematic review and meta-analysis was conducted in accordance with the preferred reporting items for systematic reviews and meta-analysis guidelines,and PubMed/MEDLINE,Scopus,and Cochrane Central were searched from inception till August 2023.Primary outcomes were major adverse cardiac events(MACE),cardiac death,myocardial infarction(MI),cardiac death or MI,and ischemia-driven total lesion revascularization(ID-TLR).RESULTS Four randomized controlled trials(RCT),which analyzed a sum total of 3045 patients with acute coronary syndrome(ACS)after a median follow-up time of 5 years were included.Though statistically insignificant,an increase in the ID-TLR was observed in patients receiving TiNOSs vs DESs.In addition,MI,cardiac death and MI,and definite stent thrombosis(DST)were significantly decreased in the TiNOS arm.Baseline analysis revealed no significant results with meta-regression presenting non-ST elevated MI(NSTEMI)as a statistically significant covariate in the outcome of MACE.CONCLUSION TiNOS was found to be superior to DES in terms of MI,cardiac death or MI,and DST outcomes,however,the effect of the two stent types on ID-TLR and MACE was not significant.A greater number of studies are required to establish an accurate comparison of patient outcomes in TiNOS and DES.

关键词： Stents Drug-eluting Major adverse cardiac events All-cause death Meta-analysis