mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Microbial Biomass Dynamics in a Tropical Agroecosystem: Influence of Herbicide and Soil Amendments

The influences of herbicide alone and in combination with the soil amendments with contrasting resource qualities on dynamics of soil microbial biomass C(MBC), N(MBN), and P(MBP) were studied through two annual cycles in rice-wheat-summer fallow crop sequence in a tropical dryland agroecosystem. The experiment included application of herbicide(butachlor) alone or in combination with various soil amendments having equivalent amount of N in the forms of chemical fertilizer, wheat straw, Sesbania aculeata, and farm yard manure(FYM). Soil microbial biomass showed distinct temporal variations in both crop cycles, decreased from vegetative to grain-forming stage, and then increased to maximum at crop maturity stage. Soil MBC was the highest in herbicide+ Sesbania aculeata treatment followed by herbicide+ FYM, herbicide+ wheat straw, herbicide+ chemical fertilizer, and herbicide alone treatments in decreasing order during the rice-growing period. During wheat-growing period and summer fallow, soil MBC attained maximum for herbicide+ wheat straw treatment whereas herbicide+ FYM, herbicide+ Sesbania, and herbicide+ chemical fertilizer treatments showed similar levels. The overall trend of soil MBN was similar to those of soil MBC and MBP except that soil MBN was higher in herbicide+ chemical fertilizer treatment over the herbicide+ wheat straw treatment during rice-growing period. In spite of the addition of equivalent amount of N through exogenous soil amendments in combination with the herbicide, soil microbial biomass responded differentially to the treatments. The resource quality of the amendments had more pronounced impact on the dynamics of soil microbial biomass, which may have implications for long-term sustainability of rainfed agroecosystems in dry tropics.
Reconstruction of Soil Particle Composition During Freeze-Thaw Cycling: A Review

Studies conducted over several decades have shown that the freeze-thaw cycles are a process of energy input and output in soil, which help drive the formation of soil structure, through water expansion by crystallization and the movement of water and salts by thermal gradients. However, most of these studies are published in Russian or Chinese and are less accessible to international researchers. This review brought together a wide range of studies on the effects of freezing and thawing on soil structure. The following findings are summarized: i) soil structure after freeze-thaw cycles changes considerably and the changes are due to the mechanical fragmentation of soil coarse mineral particles and the aggregation of soil fine particles; ii) the particle size of soil becomes homogeneous and the variation in soil structure weakens as the number of freeze-thaw cycles increases; iii) in the freezing process of soil, an important principle in the variation of soil particle bonding is presented as: condensation → aggregation → crystallization; iv) the freeze-thaw cycling process has a strong effect on soil structure by changing the granulometric composition of mineral particles and structures within the soil. The freeze-thaw cycling process strengthens particle bonding, which causes an overall increase in aggregate stability of soil, showing a process from destruction to reconstruction.
创业维艰写沧桑,功在千秋放光芒

中国早期地学有着鲜明的时代特点,既吸收了西方发达国家先进的科学思想,又在本国广袤的土地上有许多划时代的发现。自1913年中央地质调查所成立起,地学先辈们便在时代动荡、交通不便、物资匮乏的条件下,为了科学探索和救国自强,开始风餐露宿、跋山涉水,东到江浙沿海,西至西藏新疆,开创中国早期地学事业。
Effect of Temperature on Microstructure and Formability of Al-10 mass%Si Coatings

The type-1 aluminized(Al-10 mass%Si)coating on hot stamped steel is used in commercial applications. The effect of temperature on microstructure and formability of the Al-10 mass%Si coating was investigated.Hot-dip aluminized 22MnB5 steel was heated at 870,900,930,and 1 050℃ for 5 min.After heat treatment at different temperatures,the microstructure of Al-10 mass%Si was characterized by field-emission scanning electron microscopy and energy-dispersive spectroscopy.The results show that when the Al-10 mass%Si coating was heated at 870℃ for 5 min,three types of intermetallic phases were formed:two ternary Fe-Si-Al phases(Fe_2SiAl_7+Fe_2Si_2Al_5 and Fe_2SiAl_2+Fe_2Si_2Al_5)and one binary Fe-Al phase(FeAl_3).The phases in the coating became Fe_2SiAl_2+Fe_2Si_2Al_5 and FeAl_3,the binary Fe-Al phase near the interface became Fe_2Al_5 and the Si-rich layers were decreased with the increase of heating temperature.When the heat treatment was 1 050℃ for 5 min,the Si-rich layer disappeared,the coating consisted of FeAl and Fe_3Al,and the Kirkendall voids were formed.When the heating temperature was increased through 870,900,and 930℃, the coating hardness was reduced and cracks were formed in the coating after hot stamping.The formability of the coating with temperature change was confirmed by a hot stamping test.When heated at 1 050℃, the coating was formable but continuous Kirkendall voids were observed.
Why some tumours trigger neovascularisation and others don’t: the story thus far

Background: Angiogenesis is not essential for tumours to develop and expand, as cancer can also grow in a nonangiogenic fashion, but why this type of growth occurs is unknown. Surprisingly, our data from mRNA transcription profiling did not show any differences in the classical angiogenic pathways, but differences were observed in mitochondrial metabolic pathways, suggesting a key role for metabolic reprogramming. We then validated these results with mRNA profiling by investigating differential protein expression via immunohistochemistry in angiogenic and non-angiogenic non-small cell lung cancers (NSCLCs). Methods: Immunohistochemical staining for 35 angiogenesis- and hypoxia-related biomarkers were performed on a collection of 194 angiogenic and 73 non-angiogenic NSCLCs arranged on tissue microarrays. Sequencing of P53 was performed with frozen tissue samples of NSCLC. Results: The non-angiogenic tumours were distinguished from the angiogenic ones by having higher levels of proteins associated with ephrin pathways, mitochondria, cell biogenesis, and hypoxia-inducible factor 1 (HIF1) regulation by oxygen and transcription of HIF-controlled genes but lower levels of proteins involved in the stroma, cell–cell signaling and adhesion, integrins, and Delta-Notch and epidermal growth factor (EGF)-related signaling. However, proteins classically associated with angiogenesis were present in both types of tumours at very comparable levels. Cytoplasmic expression of P53 was strongly associated with non-angiogenic tumours. A pilot investigation showed that P53 mutations were observed in 32.0% of angiogenic cases but in 71.4% of non-angiogenic tumours. Conclusions: Our observations thus far indicate that both angiogenic and non-angiogenic tumours experience hypoxia/HIF and vascular endothelial growth factor (VEGF) pathway protein expression in a comparable fashion. However, angiogenesis does not ensue in the non-angiogenic tumours. Surprisingly, metabolic reprogramming seems to distinguish these two types of neoplastic growth. On the basis of these results, we raise the hypothesis that in some, but not in all cases, initial tissue remodeling and/or inflammation could be one of the secondary steps necessary to trigger angiogenesis. In the non-angiogenic tumours, in which neovascularisation fails to occur, HIF pathway activation could be the driving force toward metabolic reprogramming.
Impacts of climatic and marine environmental variations on the spatial distribution of Ommastrephes bartramii in the Northwest Pacific Ocean

Ommastrephes bartramii is an ecologically dependent species and has great commercial values among the Asia- Pacific countries. This squid widely inhabits the North Pacific, one of the most dynamic marine environments in the world, subjecting to multi-scale climatic events such as the Pacific Decadal Oscillation (PDO). Commercial fishery data from the Chinese squid-jigging fleets during 1995–2011 are used to evaluate the influences of climatic and oceanic environmental variations on the spatial distribution of O. bartramii. Significant interannual and seasonal variability are observed in the longitudinal and latitudinal gravity centers (LONG and LATG) of fishing ground of O. bartramii. The LATG mainly occurred in the waters with the suitable ranges of environmental variables estimated by the generalized additive model. The apparent north-south spatial shift in the annual LATG appeares to be associated with the PDO phenomenon and is closely related to the sea surface temperature (SST) and sea surface height (SSH) on the fishing ground, whereas the mixed layer depth (MLD) might contribute limited impacts to the distribution pattern of O. bartramii. The warm PDO regimes tend to yield cold SST and low SSH, resulting in a southward shift of LATG, while the cold PDO phases provid warm SST and elevated SSH, resulting in a northward shift of LATG. A regression model is developed to help understand and predict the fishing ground distributions of O. bartramii and improve the fishery management.
On the Atom-Bond Connectivity Index of Two-Trees

The atom-bond connectivity (ABC) index of a graph G, introduced by Estrada, Torres, Rodriguez and Gutman in 1998,is defined as the sum of the weights of all edges V_iV_j of G, where di denotes the degree of the vertex V_i in G. In this paper, we give an upper bound of the ABC index of a two-tree G with n vertices, that is, ABC(G) ≤.We also determine the two-trees with the maximum and the second maximum ABC index.
Novel Linear Piezoelectric Motor for Precision Position Stage

Conventional servomotor and stepping motor face challenges in nanometer positioning stages due to the complex structure, motion transformation mechanism, and slow dynamic response, especially directly driven by linear motor. A new butterfly-shaped linear piezoelectric motor for linear motion is presented. A two-degree precision position stage driven by the proposed linear ultrasonic motor possesses a simple and compact configuration, which makes the system obtain shorter driving chain. Firstly, the working principle of the linear ultrasonic motor is analyzed. The oscillation orbits of two driving feet on the stator are produced successively by using the anti-symmetric and symmetric vibration modes of the piezoelectric composite structure, and the slider pressed on the driving feet can be propelled twice in only one vibration cycle. Then with the derivation of the dynamic equation of the piezoelectric actuator and transient response model, start-upstart-up and settling state characteristics of the proposed linear actuator is investigated theoretically and experimentally, and is applicable to evaluate step resolution of the precision platform driven by the actuator. Moreover the structure of the two-degree position stage system is described and a special precision displacement measurement system is built. Finally, the characteristics of the two-degree position stage are studied. In the closed-loop condition the positioning accuracy of plus or minus <0.5 μm is experimentally obtained for the stage propelled by the piezoelectric motor. A precision position stage based the proposed butterfly-shaped linear piezoelectric is theoretically and experimentally investigated.
Continuous Separation of Multiple Size Microparticles using Alternating Current Dielectrophoresis in Microfluidic Device with Acupuncture Needle Electrodes

The need to continuously separate multiple microparticles is required for the recent development of lab-on-chip technology. Dielectrophoresis(DEP)-based separation device is extensively used in kinds of microfluidic applications. However, such conventional DEP-based device is relatively complicated and difficult for fabrication. A concise microfluidic device is presented for effective continuous separation of multiple size particle mixtures. A pair of acupuncture needle electrodes are creatively employed and embedded in a PDMS(poly-dimethylsiloxane) hurdle for generating non-uniform electric field thereby achieving a continuous DEP separation. The separation mechanism is that the incoming particle samples with different sizes experience different negative DEP(nDEP) forces and then they can be transported into different downstream outlets. The DEP characterizations of particles are calculated, and their trajectories are numerically predicted by considering the combined action of the incoming laminar flow and the nDEP force field for guiding the separation experiments. The device performance is verified by successfully separating a three-sized particle mixture, including polystyrene microspheres with diameters of 3 μm, 10 μm and 25 μm. The separation purity is below 70% when the flow rate ratio is less than 3.5 or more than 5.1, while the separation purity can be up to more than 90% when the flow rate ratio is between 3.5 and 5.1 and meanwhile ensure the voltage output falls in between 120 V and 150 V. Such simple DEP-based separation device has extensive applications in future microfluidic systems.
虚拟切片和数码互动在组织学教学中的应用

组织学是研究机体微细结构及其相关功能的科学,是重要的医学基础课程。组织学借助于显微镜观察和讲解组织的微观形态,实验教学是其教学的重要环节。传统教学中,教师利用图谱讲解形态与功能,学生使用光学显微镜观察传统组织切片加深对理论知识的理解和记忆。然而,这种传统的教学模式有诸多弊端:如传统组织切片标本来源日益稀少、制作繁琐、成本高、保存不易、以及显微镜在使用上受到时间空间的限制等等。传统组织切片的局限性影响了教学效果,妨碍了学生的自主学习。随着信息技术和数字化的发展,将传统组织切片转换为数字切片,建立数字切片库,并与数码互动系统结合,有利于提高组织学教学效果。
胃癌细胞三维培养体系的建立

一直以来,二维细胞培养体系是体外研究细胞生物学特性的主要实验平台,但由于该培养体系的局限性等因素,使得细胞的极性、形态、功能以及基因表达均与人在体内细胞的实际生长情况差别很大,致使二维培养体系下的细胞对外界刺激做出的反应与在体细胞相差甚远。因此,利用二维细胞培养体系探讨肿瘤细胞的生物学特征及肿瘤发生、发展的机制面临越来越多的质疑。而三维细胞培养体系则是基于立体培养模式的细胞培养体系,它能更好地模拟在体细胞的生长微环境,在研究肿瘤细胞的生物学特征等方面显示出了明显的优势。本研究拟模拟在体胃癌细胞的生存状态,在琼脂表面或以胶原混合物为依托建立胃癌细胞的三维培养体系,为体外研究胃癌细胞的生物学特征提供新的实验平台。
内质网应激与脊髓继发性损伤关系的研究进展

脊髓损伤主要由外界暴力造成,致残率高,明确其病理机制和寻找治疗方法具有重要意义。Allen在1911年首次提出了二期损伤理论,将急性脊髓损伤分为直接损伤和继发损伤。直接损伤引发了损伤部位神经血管微环境变化,从而导致继发损伤。继发损伤是脊髓损伤后机体功能减退的主要原因,然而具体的病理机制仍不清楚,但近年来研究表明继发损伤与内质网应激(endoplasmic reticulum stress, ERS)密切相关。ERS是细胞在应激条件下作出的一系列适应性调节反应,可以根据应激的强弱与持续时间决定细胞的存亡,从而影响机体功能。明确ERS的机制及其在脊髓继发性损伤中的作用将有助于寻找脊髓继发性损伤的治疗靶点,改善脊髓损伤患者的功能恢复,提高生活质量。为此,笔者阐述ERS的机制及其与脊髓继发性损伤的关系,介绍药物干预ERS的研究进展,并指出脊髓损伤后ERS未来的研究方向。
钾盐镀锌长效低消耗光亮剂

自20世纪80年代初开始,以苄叉丙酮为主光亮剂的钾盐镀锌工艺,因镀锌层达到了镜面光亮的效果而被人们所认可。 20世纪90年代中期,以邻氯苯甲醛为主光亮剂的钾盐镀锌工艺兴起。采用该工艺得到的镀锌层外观亮度更胜一筹,形成清亮的白色。
Matrix expression and vaccination control for epidemic dynamics over dynamic networks

This paper investigates epidemic dynamics over dynamic networks via the approach of semi-tensor product of matrices. First, a formal susceptible-infected-susceptible epidemic dynamic model over dynamic networks (SISED-DN) is given. Second, based on a class of determinate co-evolutionary rule, the matrix expressions are established for the dynamics of individual states and network topologies, respectively. Then, all possible final spreading equilibria are obtained for any given initial epidemic state and network topology by the matrix expression. Third, a sufficient and necessary condition of the existence of state feedback vaccination control is presented to make every individual susceptible. The study of illustrative examples shows the effectiveness of our new results.
Charge recombination mechanism to explain the negative capacitance in dye-sensitized solar cells

Negative capacitance (NC) in dye-sensitized solar cells (DSCs) has been confirmed experimentally. In this work, the recombination behavior of carriers in DSC with semiconductor interface as a carrier's transport layer is explored theoretically in detail. Analytical results indicate that the recombination behavior of carriers could contribute to the NC of DSCs under small signal perturbation. Using this recombination capacitance we propose a novel equivalent circuit to completely explain the negative terminal capacitance. Further analysis based on the recombination complex impedance show that the NC is inversely proportional to frequency. In addition, analytical recombination resistance is composed by the alternating current (AC) recombination resistance (R_(rac)) and the direct current (DC) recombination resistance (R_(rdc)), which are caused by small-signal perturbation and the DC bias voltage, respectively. Both of two parts will decrease with increasing bias voltage.
Effect of exchange coupling on magnetic property in Sm-Co/α-Fe layered system

The hysteresis loops as well as the spin distributions of Sm-Co/a-Fe bilayers have been investigated by both threedimensional (3D) and one-dimensional (1D) micromagnetic calculations, focusing on the effect of the interface exchange coupling under various soft layer thicknesses t~s. The exchange coupling coefficient A~(hs) between the hard and soft layers varies from 1.8×10~(-6) erg/cm to 0.45×10~(-6) erg/cm, while the soft layer thickness increases from 2 nm to 10 nm. As the exchange coupling decreases, the squareness of the loop gradually deteriorates, both pinning and coercive fields rise up monotonically, and the nucleation field goes down. On the other hand, an increment of the soft layer thickness leads to a significant drop of the nucleation field, the deterioration of the hysteresis loop squareness, and an increase of the remanence. The simulated loops based on the 3D and 1D methods are consistent with each other and in good agreement with the measured loops for Sm-Co/a-Fe multilayers.
High-power electro-optic switch technology based on novel transparent ceramic

A novel high-power polarization-independent electro-optic switch technology based on a reciprocal structure Sagnac interferometer and a transparent quadratic electro-optic ceramic is proposed and analyzed theoretically and experimentally. The electro-optic ceramic is used as a phase retarder for the clockwise and counter-clockwise polarized light, and their polarization directions are adjusted to their orthogonal positions by using two half-wave plates. The output light then becomes polarization-independent with respect to the polarization direction of the input light. The switch characteristics, including splitter ratios and polarization states, are theoretically analyzed and simulated in detail by the matrix multiplication method. An experimental setup is built to verify the analysis and experimental results. A new component ceramic is used and a nonpolarizing cube beam splitter (NPBS) replaces the beam splitter (BS) to lower the ON/OFF voltage to 305 V and improve the extinction ratio by 2 dB. Finally, the laser-induced damage threshold for the proposed switch is measured and discussed. It is believed that potential applications of this novel polarization-independent electro-optic switch technology will be wide, especially for ultrafast high-power laser systems.
Hysteresis-induced bifurcation and chaos in a magneto-rheological suspension system under external excitation

The magneto-rheological damper (MRD) is a promising device used in vehicle semi-active suspension systems, for its continuous adjustable damping output. However, the innate nonlinear hysteresis characteristic of MRD may cause the nonlinear behaviors. In this work, a two-degree-of-freedom (2-DOF) MR suspension system was established first, by employing the modified Bouc-Wen force-velocity (F-v) hysteretic model. The nonlinear dynamic response of the system was investigated under the external excitation of single-frequency harmonic and bandwidth-limited stochastic road surface. The largest Lyapunov exponent (LLE) was used to detect the chaotic area of the frequency and amplitude of harmonic excitation, and the bifurcation diagrams, time histories, phase portraits, and power spectrum density (PSD) diagrams were used to reveal the dynamic evolution process in detail. Moreover, the LLE and Kolmogorov entropy (K entropy) were used to identify whether the system response was random or chaotic under stochastic road surface. The results demonstrated that the complex dynamical behaviors occur under different external excitation conditions. The oscillating mechanism of alternating periodic oscillations, quasi-periodic oscillations, and chaotic oscillations was observed in detail. The chaotic regions revealed that chaotic motions may appear in conditions of mid-low frequency and large amplitude, as well as small amplitude and all frequency. The obtained parameter regions where the chaotic motions may appear are useful for design of structural parameters of the vibration isolation, and the optimization of control strategy for MR suspension system.
Pulsed arterial spin labeling effectively and dynamically observes changes in cerebral blood flow after mild traumatic brain injury

Cerebral blood flow is strongly associated with brain function, and is the main symptom and diagnostic basis for a variety of encephalopathies. However, changes in cerebral blood flow after mild traumatic brain injury remain poorly understood. This study sought to observe changes in cerebral blood flow in different regions after mild traumatic brain injury using pulsed arterial spin labeling. Our results demonstrate maximal cerebral blood flow in gray matter and minimal in the white matter of patients with mild traumatic brain injury. At the acute and subacute stages, cerebral blood flow was reduced in the occipital lobe, parietal lobe, central region, subcutaneous region, and frontal lobe. Cerebral blood flow was restored at the chronic stage. At the acute, subacute, and chronic stages, changes in cerebral blood flow were not apparent in the insula. Cerebral blood flow in the temporal lobe and limbic lobe diminished at the acute and subacute stages, but was restored at the chronic stage. These findings suggest that pulsed arterial spin labeling can precisely measure cerebral blood flow in various brain regions, and may play a reference role in evaluating a patient’s condition and judging prognosis after traumatic brain injury.
New insight into curcumin-based therapy in spinal cord injuries: CISD2 regulation

Multiple protective effects of curcumin in cases of spinal cord injuries (SCIs): Curcumin [1,7-bis(4-hydroxy-3-methoxyphenyl)- 1,6-heptadiene-3,5-dione] is a nonsteroidal, naturally occurring compound commonly utilized as a dietary pigment as well as a spice in India. It is obtained from curcuma longa in the Ginger family. Due to its anti-inflammatory, anti-oxidant, and immunomodulatory activities, this extract has been used to treat a number of inflammatory and neurodegenerative conditions, including Alzheimer’s disease, multiple sclerosis, and trauma to the central nervous system (Menon and Sudheer, 2007). Curcumin antagonizes several processes involved in the inflammatory cascade, including the activation of nuclear factor kappa B (NF-κB) and inducible nitric oxide synthase (iNOS) (Weber et al., 2006). It has also been shown to scavenge NO, decrease lipid peroxidation, and attenuate mitochondrial dysfunction (Wang et al., 2005).
Considering calcium-binding proteins in invertebrates: multi-functional proteins that shape neuronal growth

Calcium is a critical second messenger molecule in all cells and is vital in neurons for synaptic transmission. Given this importance, calcium ions are tightly controlled by a host of molecular players including ion channels, sensors, and buffering proteins. Calcium can act directly by binding to signaling molecules or calcium’s effects can be indirect, for example by altering nuclear histones which can lead to changes in gene transcription (Rishal and Fainzilber, 2014). All of these mechanisms come into play in developing axons as calcium is required for both axon pathfinding and branching. Furthermore, after neuronal injury, waves of calcium originating at the site of axon segmentation and propagating to the nucleus have long been known to be required for regeneration (Rishal and Fainzilber, 2014). These changes in intracellular calcium concentrations [Ca~(2+)]i must be properly controlled or else new growth cones may fail to form and degeneration of the neuron may occur. While many of the molecular players involved in these calcium-dependent processes have been identified, calcium buffering proteins have often been undervalued for their role in regulating axon growth either during normal development or in the event of injury.