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关键词： Environmental impact   Complex networks  

关键词： Mean field models   Functional equations   Kinetic equations  

摘要： In this work we study a kinetic model of active particles with delayed dynamics, and its limit when the number of particles goes to infinity. This limit turns out to be related to delayed differential equations with random initial conditions. We analyze two different dynamics, one based on the full knowledge of the individual trajectories of each particle, and another one based only on the trace of the particle cloud, loosing track of the individual trajectories. Notice that in the first dynamic the state of a particles is its path, whereas it is simply a point in R-d in the second case. We analyze in both cases the corresponding mean-field dynamic obtaining an equation for the time evolution of the distribution of the particles states. Well-posedness of the equation is proved by a fixed-point argument. We conclude the paper with some possible future research directions and modeling applications. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： acetaminophen   beta-CD/Au/TiO2/CPE   energy-dispersive X-ray spectroscopy   scanning electron microscopy   differential pulse voltammetry  

摘要： Herein, we has performed a sensitive and rapid determination of acetaminophen drug in 0.1 M phosphate buffer solution at pH 10.0 utilizing differential pulse voltammetry and a novel sensor, namely, carbon paste electrode modified with beta-cyclodextrin/gold/titanium dioxide nanocomposite. The electrochemical oxidation of acetaminophen was observed on the proposed electrode. The surface morphology of the nanomaterials was recognized using scanning electron microscopy and energy-dispersive X-ray spectroscopy confirming the material synthesis. Several parameters affecting the electrochemical responses such as electrochemical behavior of modifiers, pH value of phosphate buffer solution as a supporting electrolyte, and effect of the scan rate were assessed. In the optimum conditions, linear range and detection limit of the method were 0.10-340 mu M and 40 nM, respectively. The suggested sensor was successfully used for the drug quantification in the pharmaceutical and plasma samples with satisfactory results obtained.

关键词： Differential line driver   B-PLC system   cross-current bridge   harmonic distortion   bandwidth extension  

摘要： This paper introduces a broadband linear driver used in B-PLC system. The driver consists of two identical current-feedback amplifiers to realize a fully differential topology. A cross-current injection method between the noninverting and the inverting channels is proposed to reduce the even-order harmonics caused by the circuit mismatch. In addition, in order to increase the stability of the GBW to the changing load and maximize the bandwidth, a output stage implemented by a unit gain closed-loop amplifier is proposed to stabilize the open-loop gain of the overall circuit, meanwhile improve the linearity deteriorated by the crossover distortion. The proposed linear driver is fabricated in a SOI CBJT process and it can provide a maximum drive current of 500 mA under a 12-V power supply. The measurement results show that this linear driver is capable of driving a load of 50 Omega while achieving a output swing of 16 V-pp with a second-order harmonic distortion (HD2) of -72 dBm and a third-order harmonic distortion (HD3) of -55 dBm. The bandwidth can reach 120 MHz. A complete in-system measurement also has been passed and the results show that the proposed driver chip can well meet the need of the B-PLC system.

关键词： coral bleaching   Durusdinium   epigenetics   great star coral   MBD-BS   symbiont shuffling   thermotolerance  

摘要： Algal symbiont shuffling in favour of more thermotolerant species has been shown to enhance coral resistance to heat-stress. Yet, the mechanistic underpinnings and long-term implications of these changes are poorly understood. This work studied the modifications in coral DNA methylation, an epigenetic mechanism involved in coral acclimatization, in response to symbiont manipulation and subsequent heat stress exposure. Symbiont composition was manipulated in the great star coral Montastraea cavernosa through controlled thermal bleaching and recovery, producing paired ramets of three genets dominated by either their native symbionts (genus Cladocopium) or the thermotolerant species (Durusdinium trenchi). Single-base genome-wide analyses showed significant modifications in DNA methylation concentrated in intergenic regions, introns and transposable elements. Remarkably, DNA methylation changes in response to heat stress were dependent on the dominant symbiont, with twice as many differentially methylated regions found in heat-stressed corals hosting different symbionts (Cladocopium vs. D. trenchii) compared to all other comparisons. Interestingly, while differential gene body methylation was not correlated with gene expression, an enrichment in differentially methylated regions was evident in repetitive genome regions. Overall, these results suggest that changes in algal symbionts favouring heat tolerant associations are accompanied by changes in DNA methylation in the coral host. The implications of these results for coral adaptation, along with future avenues of research based on current knowledge gaps, are discussed in the present work.

关键词： 常微分方程-边值问题-研究  

ISBN: (纸本)9787030709011

摘要： 本书研究无穷区间上常微分方程边值问题的非线性泛函分析理论，内容共七章，其中前两章系统介绍无穷边值问题、函数空间和非线性泛函理论的基础；第3-7章分别给出了五种方法研究二阶和高阶常微分方程、具有p-Laplace算子的微分方程、差分方程以及方程组的特征值问题、两点边值问题、多点边值问题、共振问题、周期解、次调和解和反周期解问题的研究结果。全书比较系统、详细地讨论了不同方法在不同边值问题中的运用本书可作为高等院校数学专业研究生教材和教师的参考书，也可供科研工作者用作数学方法解决相关问题的参考书。

关键词： Oncology   Biomedicine   general  

摘要： Starting with the first-in-class agent ibrutinib, the development of Bruton tyrosine kinase (BTK) inhibitors has led to dramatic improvements in the management of B-cell malignancies. Subsequently, more-highly selective second-generation BTK inhibitors (including acalabrutinib, zanubrutinib, tirabrutinib and orelabrutinib) have been developed, primarily with an aim to reduce off-target toxicities. More recently, third-generation agents including the non-covalent BTK inhibitors pirtobrutinib and nemtabrutinib have entered later-stage clinical development. BTK inhibitors have shown strong activity in a range of B-cell malignancies, including chronic lymphocytic leukaemia/small lymphocytic lymphoma, mantle cell lymphoma, Waldenström’s macroglobulinaemia and marginal zone lymphoma. The agents have acceptable tolerability, with adverse events generally being manageable with dosage modification. This review article summarises the evidence supporting the role of BTK inhibitors in the management of B-cell malignancies, including highlighting some differential features between agents.

关键词： cannabinoids   Cannabis sativa   anandamide   Delta(9)-tetrahydrocannabinol   cannabidiol   cannabigerol   cannabinol   cannabidivarin   breast cancer  

摘要： Although cannabinoids have been used for centuries for diverse pathological conditions, recently, their clinical interest and application have emerged due to their diverse pharmacological properties. Indeed, it is well established that cannabinoids exert important actions on multiple sclerosis, epilepsy and pain relief. Regarding cancer, cannabinoids were first introduced to manage chemotherapy-related side effects, though several studies demonstrated that they could modulate the proliferation and death of different cancer cells, as well as angiogenesis, making them attractive agents for cancer treatment. In relation to breast cancer, it has been suggested that estrogen receptor-negative (ER-) cells are more sensitive to cannabinoids than estrogen receptor-positive (ER+) cells. In fact, most of the studies regarding their effects on breast tumors have been conducted on triple-negative breast cancer (TNBC). Nonetheless, the number of studies on human epidermal growth factor receptor 2-positive (HER2(+)) and ER+ breast tumors has been rising in recent years. However, besides the optimistic results obtained thus far, there is still a long way to go to fully understand the role of these molecules. This review intends to help clarify the clinical potential of cannabinoids for each breast cancer subtype.

关键词： corticostriatal   in vivo   learning   neurophysiology  

摘要： It has been hypothesized that to perform sensorimotor transformations efficiently, somatosensory information being fed back to a particular motor circuit is organized in accordance with the mechanical loading patterns of the skin that result from the motor activity generated by that circuit. Rearrangements of sensory information to different motor circuits could in this respect constitute a key component of sensorimotor learning. We here explored whether the organization of tactile input from the plantar forepaw of the rat to cortical and striatal circuits is affected by a period of extensive sensorimotor training in a skilled reaching and grasping task. Our data show that the representation of tactile stimuli in terms of both temporal and spatial response patterns changes as a consequence of the training and that spatial changes particularly involve the primary motor cortex. Based on the observed reorganization, we propose that reshaping of the spatiotemporal representation of the tactile afference to motor circuits is an integral component of the learning process that underlies skill acquisition in reaching and grasping. NEW & NOTEWORTHY Sensorimotor transformations are fundamental to the function of the nervous system and determine how patterns of sensory input are converted into appropriate movements. We here investigated the extent to which experience -dependent processes can reshape the organization of somatosensory input feeding into cortico-basal ganglia motor structures. Our data point to a particularly important role for the primary motor cortex in the functional adaptions associated with skilled motor learning.