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| 1 | 生物入侵过程中的植物-土壤反馈:一种入侵植物的凋落物分解对其本地近缘植物的影响显示文摘植物入侵可通过正或负的植物-土壤反馈效应改变土壤的生物和非生物性质,从而影响入侵栖息地的土壤理化性质。许多入侵物种的凋落物分解可增加土壤养分,降低本地植物多样性,并导致进一步的植物入侵。关于入侵植物凋落物在不同土壤类型及深度分解及反馈效应的研究依然很少。本研究旨在明确入侵植物南美蟛蜞菊(Sphagneticola trilobata)凋落物在不同土壤类型和不同土壤深度条件下的分解情况及其对本地近缘植物蟛蜞菊(S.calendulacea)生理生长的影响。将装有南美蟛蜞菊凋落物的尼龙袋加入到不同深度(即0、2、4和6 cm)的砂土、营养土和粘土中,经6个月的分解后,回收凋落物袋并计算分解速率,随后在凋落物分解处理后的土壤中种植本地蟛蜞菊,并在生长期结束时测量其生理生态指标。研究结果表明,所有处理土壤类型中,凋落物在土壤深度为2和4 cm处分解后显著增加了土壤养分,而对本地蟛蜞菊的叶片叶绿素、叶氮含量等生长指标表现为负效应。因此,入侵植物南美蟛蜞菊凋落物分解对土壤养分表现为正的反馈效应,而对本地植物蟛蜞菊的生长表现为负效应。我们的研究结果还表明,入侵植物的凋落物分解对土壤和本地物种的影响还因凋落物分解所在的土壤深度而显著不同。未来的研究应侧重于入侵栖息地中更多本地和入侵物种的植物-土壤反馈效应,以及更多土壤类型和土壤深度的入侵植物凋落物效应。 | Jianfan Sun Susan Rutherford Muhammad Saif Ullah Ikram Ullah Qaiser Javed Ghulam Rasool Muhammad Ajmal Ahmad Azeem Muhammad Junaid Nazir Daolin Du | 2022 | Journal of Plant Ecology2022，15，3： | 2 |
| 2 | 烧结铜丝和沟槽热管热性能特性的实验研究显示文摘热管是最常用的热管理解决方案。为达到最佳效果,在特定的情况下选择合适的热管类型是非常必要的。本研究的目的是比较烧结铜丝热管和沟槽热管两种常用热管的热性能特点。采用重力辅助定位实验对充蒸馏水热管进行了测试,得到毛细管压力、操作温度、热阻和传热系数等参数结果。烧结热管的毛细管压力比所有尺寸沟槽热管的都高。在相同的热负荷下,与烧结热管相比,沟槽热管的工作温度更低。在8 W热负荷下,与烧结热管相比,沟槽热管冷凝器表面温度降低8.24%,蒸发器表面温度降低4.41%,饱和温度降低7.79%。烧结热管的热阻比沟槽热管低得多,在8 W热负荷下,最大相对差值为63.8%。在8 W热负荷下,烧结热管的传热系数是开槽热管的2倍。烧结热管的热阻和传热系数随热负荷的变化几乎呈线性变化,而沟槽热管的热阻和传热系数却出现意外的拐点。与烧结热管相比,沟槽热管更早达到平衡。当热负荷从4增加至20 W时,沟槽热管达到平衡的时间从7 min缩短至4 min,烧结热管的平衡时间从10 min缩短至7 min。 | Saif Ullah KHALID Hafiz Muhammad ALI Muhammad Ali NASIR Riffat Asim PASHA ZAFAR SAID L.Syam SUNDAR Ahmed Kadhim HUSSEIN | 2021 | Journal of Central South University2021，28，11： | 0 |
| 3 | A protective role of resveratrol against the effects of immobilization stress in corpora lutea of mice in early pregnancy显示文摘In the present study,we aimed to investigate a protective role for resveratrol against the effects of immobilization stress on corpora lutea(CL)of mice in early pregnancy.A total of 45 early-pregnant mice were divided into no immobilization stress(NIS)group,immobilization stress(IS)group,and immobilization and resveratrol treatment(IS+RES)group(n=15).Mice were immobilized in plastic tubes(50 mL)for 3 h per day during day 1 to 7 of pregnancy.In the IS+RES group,5 mg kg-'d-1 of resveratrol was administered just prior to application of stress.We analyzed apoptotic activity in CL by Western botting analysis(WB),transmission electron microscopy(TEM),and immunohistochemistry(IHC).Serum progesterone levels were examined with radioimmunoassay(RIA).IHC results showed that the intensity of positive staining for Bax was increased,and for BcI-2 was decreased in CL after IS,while resveratrol treatment reversed the positive staining for Bax and Bcl-2.WB revealed that immobilization stress up-regulated the expression of Bax and caspase-9,and down-regulated Bcl-2 expression,while resveratrol treatment attenuated the effects of immobilization stress on the expression of Bax,Bcl-2 and caspase-9.According to our TEM results,apoptosis as defined by chromatin condensation was found in CL after immobilization stress,while resveratrol inhibited the apoptosis.We also demonstrated that immobilization stress decreased progesterone concentrations and ovarian expression of StAR,while resveratrol restored the concentrations of progesterone and expression of StAR back to normal.These results indicated that immobilization stress induced luteal regression while resveratrol inhibited luteal regression,suggesting that resveratrol plays a protective role on corpora lutea of mice during early pregnancy. | Saif ULLAH Sheeraz MUSTAFA Wael ENNAB Muhammad JAN Muhammad SHAFIQ Ngekure MXKAVITA LU Zeng-peng MAO Da-gan SHI Fang-xiong | 2020 | Journal of Integrative Agriculture2020，19，7： | 0 |
| 4 | Behavioral effects of a four-wing attractor with circuit realization: a cryptographic perspective on immersion显示文摘In this paper,we propose an innovative chaotic system,combining fractional derivative and sinehyperbolic nonlinearity with circuit execution.The study of this system is conducted via an analog circuit simulator,using two anti-parallel semiconductor diodes to provide hyperbolic sine nonlinearity,and to function as operational amplifiers.The multi-stability of the system is also enhanced with the help of multi-equilibrium points for distinct real orders of system.The system explores the generation of a four-wing attractor in different phases,both numerically and electronically.By changing the input parameters of the system,different graphs are generated for current flow in state,phase,and space,to confirm the precision of the fractional order derivatives.A reasonable simulation shows that the deliberate circuit provides effective chaos in terms of speed and accuracy,which is comensurate with the numerical simulation.This nonlinear chaotic behavior is utilized to encrypt sound(.wav),images(.jpg),and animated(.gif)data which are a major requirement for the security of communication systems.The proposed circuit performs chaos and cryptographic tasks with high-effective analog computation,and constitutes a novel approach to this area of research. | Najeeb Alam Khan Muhammad Ali Qureshi Tooba Hameed Saeed Akbar Saif Ullah | 2020 | Communications in Theoretical Physics2020，72，12： | 0 |
| 5 | Performance Analysis of Magnetic Nanoparticles during Targeted Drug Delivery:Application of OHAM显示文摘In recent years,the emergence of nanotechnology experienced incredible development in the field of medical sciences.During the past decade,investigating the characteristics of nanoparticles during fluid flow has been one of the intriguing issues.Nanoparticle distribution and uniformity have emerged as substantial criteria in both medical and engineering applications.Adverse effects of chemotherapy on healthy tissues are known to be a significant concern during cancer therapy.A novel treatment method of magnetic drug targeting(MDT)has emerged as a promising topical cancer treatment along with some attractive advantages of improving efficacy,fewer side effects,and reduce drug dose.During magnetic drug targeting,the appropriate movement of nanoparticles(magnetic)as carriers is essential for the therapeutic process in the blood clot removal,infection treatment,and tumor cell treatment.In this study,we have numerically investigated the behavior of an unsteady blood flowinfused with magnetic nanoparticles during MDT under the influence of a uniform external magnetic field in a microtube.An optimal homotopy asymptotic method(OHAM)is employed to compute the governing equation for unsteady electromagnetohydrodynamics flow.The influence of Hartmann number(Ha),particle mass parameter(G),particle concentration parameter(R),and electro-osmotic parameter(k)is investigated on the velocity of magnetic nanoparticles and blood flow.Results obtained show that the electro-osmotic parameter,along with Hartmann’s number,dramatically affects the velocity of magnetic nanoparticles,blood flow velocity,and flow rate.Moreover,results also reveal that at a higher Hartman number,homogeneity in nanoparticles distribution improved considerably.The particle concentration andmass parameters effectively influence the capturing effect on nanoparticles in the blood flow using a micro-tube for magnetic drug targeting.Lastly,investigation also indicates that the OHAM analysis is efficient and quick to handle the system of nonlinear equations. | Muhammad Zafar Muhammad Saif Ullah Tareq Manzoor Muddassir Ali Kashif Nazar Shaukat Iqbal HabibUllah Manzoor Rizwan Haider Woo Young Kim | 2022 | Computer Modeling in Engineering & Sciences2022，，2： | 0 |
| 6 | Modeling and scientific computing for the transmission dynamics of Avian influenza with half-saturated incidence显示文摘This paper presents the mathematical analysis of the dynamical system for avian influenza.The proposed model considers a nonlinear dynamical model of birds and human.The half-saturated incidence rate is used for the transmission of avian influenza infection.Rigorous mathematical results are presented for the proposed models.The local and global dynamics of each model are presented and proven that when R0<1,then the disease-free equilibrium of each model is stable both locally and globally,and when R0>1,then the endemic equilibrium is stable both locally and globally.The numerical results obtained for the proposed model shows that influenza could be eliminated from the community if the threshold is not greater than unity. | Muhammad Altaf Khan Saif Ullah Yasir Khan Muhammad Farhan | 2020 | International Journal of Modeling, Simulation, and Scientific Computing2020，11，4： | 0 |
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