WAVE

WAVE
  • 文章类型: Journal Article
    考虑了通过使用安装在波导杆表面附近的电动传感器测量纵向位移的幅度来确定进入负载的纵向超声振动的声功率的方法。详细分析了使用开发的测量方法的两种可能性。其中之一是基于在超声系统的两种不同状态下在电动传感器的恒定位置处的纵向位移值的配准:在负载断开的情况下以及在连接负载之后,即它在不同的时刻使用两个测量值,当系统的状态彼此不同时。另一种方法使用在振荡系统的两个选定点处对纵向振荡的幅度进行两次测量,同时制作。已经获得了公式,这些公式可以根据系统参数的测量值和其他已知值确定进入负载的功率。错误的作用,在传感器的读数和确定其在振荡系统上的位置时,关于计算进入负载的超声波振荡的功率值的准确性进行了分析。
    The way of determining the acoustic power of longitudinal ultrasonic vibrations going into the load by measuring the amplitude of longitudinal displacements using an electrodynamic sensor installed near the surface of the waveguide rod is considered. Two possibilities of using the developed method of measurement are analyzed in detail. One of them is based on the registration of the value of longitudinal displacements at the constant position of the electrodynamic sensor in two different states of the ultrasound system: with the load disconnected and after the load is connected, i.e. it uses two measurements at different moments of time, when the states of the system differ from each other. Another way uses two measurements of the amplitude of longitudinal oscillations at two chosen points of the oscillatory system, made at the same time. Formulas have been obtained that make it possible to determine the power entering the load from the measured values and other known values of the system parameters. The role of errors, both in the readings of the sensor and in determining its location on the oscillating system, on the accuracy of calculating the value of the power of the ultrasonic oscillations that went into the load is analyzed.
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  • 文章类型: Journal Article
    先天性免疫错误(IEI)是人类的一组疾病,通常表现为对感染的易感性增加,自身免疫,炎症过度,过敏,在某些情况下是恶性肿瘤。在与IEI相关的新鉴定的基因中,包括来自7个独立家族的9个个体的3个独立报告,这些个体患有严重的原发性免疫缺陷病(PID)和自身免疫,这是由于编码造血蛋白1(HEM1)的NCKAP1L基因的功能丧失突变所致。HEM1是WASp家族Verprolin同源(WAVE)调节复合物(WRC)的造血细胞特异性成分,它在多个免疫受体的下游起作用以刺激肌动蛋白成核和丝状肌动蛋白(F-actin)的聚合。F-肌动蛋白的聚合和分支对于创建产生力的细胞骨架结构至关重要,这些结构驱动大多数活跃的细胞过程,包括迁移。附着力,免疫突触形成,和吞噬作用。细胞皮质处的分支肌动蛋白网络也涉及作为屏障来调节不适当的囊泡(例如细胞因子)分泌和自发抗原受体交联。鉴于肌动蛋白细胞骨架在大多数或所有造血细胞中的重要性,HEM1缺陷患儿表现出复杂的临床表现,包括免疫缺陷和自身免疫的重叠特征,这并不奇怪.在这次审查中,我们将概述HEM1和WRC在免疫和其他细胞中的分子和细胞功能。我们将描述人类HEM1缺乏症的常见临床病理特征和免疫表型,并使用组成型和免疫细胞特异性小鼠敲除模型提供有关Hem1破坏的详细比较描述。最后,我们讨论了关于HEM1和WRC的未来观点和重要调查领域。
    Inborn errors of immunity (IEI) are a group of diseases in humans that typically present as increased susceptibility to infections, autoimmunity, hyperinflammation, allergy, and in some cases malignancy. Among newly identified genes linked to IEIs include 3 independent reports of 9 individuals from 7 independent kindreds with severe primary immunodeficiency disease (PID) and autoimmunity due to loss-of-function mutations in the NCKAP1L gene encoding Hematopoietic protein 1 (HEM1). HEM1 is a hematopoietic cell specific component of the WASp family verprolin homologous (WAVE) regulatory complex (WRC), which acts downstream of multiple immune receptors to stimulate actin nucleation and polymerization of filamentous actin (F-actin). The polymerization and branching of F-actin is critical for creating force-generating cytoskeletal structures which drive most active cellular processes including migration, adhesion, immune synapse formation, and phagocytosis. Branched actin networks at the cell cortex have also been implicated in acting as a barrier to regulate inappropriate vesicle (e.g. cytokine) secretion and spontaneous antigen receptor crosslinking. Given the importance of the actin cytoskeleton in most or all hematopoietic cells, it is not surprising that HEM1 deficient children present with a complex clinical picture that involves overlapping features of immunodeficiency and autoimmunity. In this review, we will provide an overview of what is known about the molecular and cellular functions of HEM1 and the WRC in immune and other cells. We will describe the common clinicopathological features and immunophenotypes of HEM1 deficiency in humans and provide detailed comparative descriptions of what has been learned about Hem1 disruption using constitutive and immune cell-specific mouse knockout models. Finally, we discuss future perspectives and important areas for investigation regarding HEM1 and the WRC.
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  • 文章类型: Journal Article
    背景:在塞内加尔,分子诊断被广泛用于COVID-19患者的检测和管理。然而,公共部门的基因组监测非常有限.这项研究旨在分享塞内加尔公共部门实验室应对COVID-19大流行的经验,并描述2020年和2021年流通的变体分布。
    方法:从2020年7月至2021年12月,在AristideleDantec大学教学医院的细菌学和病毒学实验室(LBV)对旅行者和有症状患者的鼻咽样本进行了SARS-CoV-2qRT-PCR。使用纳米孔技术选择循环阈值(Ct)≤30的样品用于全基因组测序(WGS)。开发了内部脚本以研究塞内加尔SARS-CoV-2变体的时空分布,使用我们的序列和从GISAID数据库检索的序列。
    结果:在接受SARS-CoV-2筛查的8,207例患者或旅行者中,970例(11.8%)为阳性,386例Ct≤30。对133个样品进行WGS。同时,在2020年和2021年,在覆盖塞内加尔九个城市的GISAID数据库中保存了高质量序列(n=1,539),我们在2020年观察到20A(B.1,B.1.416和B.1.620)和20B(B.1.1.420)谱系的高循环,而大多数样本在2021年属于Delta变体(AY34和AY.34.1,22%)。
    结论:尽管参与较晚,COVID-19诊断是在LBV中常规进行的,但基因组表征仍然具有挑战性。塞内加尔SARS-CoV-2菌株的基因组多样性反映了在大流行的第一波浪潮中在全球范围内观察到的情况。
    BACKGROUND: In Senegal, molecular diagnosis was widely used for the detection and management of COVID-19 patients. However, genomic surveillance was very limited in the public sector. This study aimed to share the experience of a Senegalese public sector laboratory in response to the COVID-19 pandemic, and to describe the distribution of variants circulating in 2020 and 2021.
    METHODS: From July 2020 to December 2021, SARS-CoV-2 qRT-PCR was performed on nasopharyngeal samples from travelers and symptomatic patients at the Bacteriology and Virology Laboratory (LBV) of the Aristide le Dantec University Teaching Hospital. Samples with a cycle threshold (Ct) ≤ 30 were selected for whole-genome sequencing (WGS) using the Nanopore technology. In-house scripts were developed to study the spatial and temporal distribution of SARS-CoV-2 variants in Senegal, using our sequences and those retrieved from the GISAID database.
    RESULTS: Of 8,207 patients or travelers screened for SARS-CoV-2, 970 (11.8%) were positive and 386 had a Ct ≤ 30. WGS was performed on 133 samples. Concomitantly with high-quality sequences deposited in the GISAID database covering nine cities in Senegal in 2020 and 2021 (n = 1,539), we observed a high circulation of the 20A (B.1, B.1.416 and B.1.620) and 20B (B.1.1.420) lineages in 2020, while most of the samples belonged to Delta variants (AY34 and AY.34.1, 22%) in 2021.
    CONCLUSIONS: Despite its late involvement, COVID-19 diagnosis was routinely performed in LBV, but genomic characterization remained challenging. The genomic diversity of SARS-CoV-2 strains in Senegal reflected that observed worldwide during the first waves of the pandemic.
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  • 文章类型: Journal Article
    虽然在急诊科罕见的诊断,低温会影响所有环境中的患者,从城市到山区。在低体温患者中无法解释经典的死亡迹象,从而导致了咒语,“没有人是死的,直到他们温暖和死亡。“对环境低温的全面回顾涵盖了低温的临床意义和病理生理学,低体温院前管理中的珍珠和陷阱(包括温度测量技术和先进的心脏生命支持偏差),必要的急诊科诊断,可用的复温方式,包括体外生命支持,和终止复苏的标准。
    Although a rare diagnosis in the Emergency Department, hypothermia affects patients in all environments, from urban to mountainous settings. Classic signs of death cannot be interpreted in the hypothermic patient, thus resulting in the mantra, \"No one is dead until they\'re warm and dead.\" This comprehensive review of environmental hypothermia covers the clinical significance and pathophysiology of hypothermia, pearls and pitfalls in the prehospital management of hypothermia (including temperature measurement techniques and advanced cardiac life support deviations), necessary Emergency Department diagnostics, available rewarming modalities including extracorporeal life support, and criteria for termination of resuscitation.
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  • 文章类型: Journal Article
    河口和海岸位于陆海界面,由于强波作用导致的沉积物液化导致沉积物-海水系统发生大量物质交换。多环芳烃(PAHs),作为有机污染物,分布在各种媒体上。在这里,通过室内微观实验结合IV级逸度模型研究了波浪对PAHs释放的影响。比较表明,静态固结阶段PAHs的释放量和释放速率最小,而波浪作用大大增强了释放。特别是处于液化状态的沉积物,第三阶段的多环芳烃释放量是第二阶段的1.55-1.86倍,达到84.73μg/L土壤强度的丧失和强大的水动力效应导致PAHs与悬浮固体一起大量释放到海水中。由于2环PAHs的挥发性和6环PAHs的难以解吸,3-5环PAHs是释放到海水中的主要贡献者。模型结果还表明,三种多环芳烃在沉积物-海水系统中的命运不同,沉积物是苯并[a]芘进入海水的重要“水库”,同时充当芘的“汇”和“源”。
    Estuaries and coasts are located at the land-sea interface, where sediment liquefaction due to strong wave action results in significant material exchange at the sediment-seawater system. Polycyclic aromatic hydrocarbons (PAHs), as organic pollutants, are distributed across various media. Herein, the impact of wave was studied on the release of PAHs through indoor microcosmic experiments combined with a level IV fugacity model. Comparison revealed that the release amount and rate of PAHs during static consolidation stage were minimal, whereas wave action substantially enhanced the release. Particularly the sediments in a liquefied state, the PAHs release in Stage III was 1.55-1.86 times that in Stage II, reaching 84.73 μg/L. The loss of soil strength and strong hydrodynamic effects resulted in a substantial release of PAHs into seawater along with suspended solids. Due to volatility of 2-ring PAHs and difficult desorption of 6-ring PAHs, 3-5-ring PAHs are the main contributors to releases into seawater. The model results also indicated that the three PAHs had different fates in the sediment-seawater system, with sediment serving as an important \"reservoir\" for benzo[a]pyrene entering seawater, while functioning as both a \"sink\" and a \"source\" for pyrene.
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  • 文章类型: Journal Article
    车载自组织网络(VANET)使用多个信道来使用车载环境中的无线接入(WAVE)标准进行通信,以提供各种车辆相关应用。当前的IEEE802.IlpWAVE通信信道结构由一个控制信道(CCH)和几个服务信道(SCH)组成。SCHs用于非安全数据传输,虽然CCH用于广播信标,control,和安全。WAVE设备传输在CCH和SCH之间交替的数据,并且每个信道在称为CCH间隔(CCHI)和SCH间隔(SCHI)的持续时间内是活动的,分别。目前,两个间隔都固定在50ms。然而,固定长度的间隔不能有效地响应动态变化的流量负载。此外,当许多车辆同时使用有限的信道资源进行数据传输时,由于大量数据包冲突,网络性能显着下降。在这里,我们提出了一种有效数据传输的自适应资源分配技术。该技术动态调整SCHI和CCHI以提高网络性能。此外,为了减少数据冲突并优化网络的退避分布,所提出的方案应用强化学习(RL)来提供智能信道接入算法。仿真结果表明,该方案可以保证高吞吐量和低传输延迟。
    Vehicular ad hoc networks (VANETs) use multiple channels to communicate using wireless access in vehicular environment (WAVE) standards to provide a variety of vehicle-related applications. The current IEEE 802.11p WAVE communication channel structure is composed of one control channel (CCH) and several service channels (SCHs). SCHs are used for non-safety data transmission, while the CCH is used for broadcasting beacons, control, and safety. WAVE devices transmit data that alternate between CCHs and SCHs, and each channel is active for a duration called the CCH interval (CCHI) and SCH interval (SCHI), respectively. Currently, both intervals are fixed at 50 ms. However, fixed-length intervals cannot effectively respond to dynamically changing traffic loads. Additionally, when many vehicles are simultaneously using the limited channel resources for data transmission, the network performance significantly degrades due to numerous packet collisions. Herein, we propose an adaptive resource allocation technique for efficient data transmission. The technique dynamically adjusts the SCHI and CCHI to improve network performance. Moreover, to reduce data collisions and optimize the network\'s backoff distribution, the proposed scheme applies reinforcement learning (RL) to provide an intelligent channel access algorithm. The simulation results demonstrate that the proposed scheme can ensure high throughputs and low transmission delays.
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  • 文章类型: Journal Article
    目的:为了研究FRONSAC编码在2D和3D波序列中的附加价值,实现FRONSAC编码梯度的轨迹映射的简单策略。
    方法:通过利用频域中的点扩散函数的稀疏性来估计每个体素的非线性梯度轨迹。模拟和体内实验用于分析波和FRONSAC编码的组合的性能。
    结果:使用简化方法的场映射产生了相似的图像质量,校准时间比以前的工作中使用的综合映射方案短得多。活体人脑图像显示,添加FRONSAC编码可以改善波形图像质量,特别是在非常高的欠采样因子和有限的波振幅的情况下。这些结果得到了g因子图的进一步支持。
    结论:结果表明,FRONSAC可用于在非常高的欠采样率或有限的采集中改善波的图像质量。我们的研究说明了所提出的快速场映射方法的潜力。
    OBJECTIVE: To study the additional value of FRONSAC encoding in 2D and 3D wave sequences, implementing a simple strategy to trajectory mapping for FRONSAC encoding gradients.
    METHODS: The nonlinear gradient trajectory for each voxel was estimated by exploiting the sparsity of the point spread function in the frequency domain. Simulations and in-vivo experiments were used to analyze the performance of combinations of wave and FRONSAC encoding.
    RESULTS: Field mapping using the simplified approach produced similar image quality with much shorter calibration time than the comprehensive mapping schemes utilized in previous work. In-vivo human brain images showed that the addition of FRONSAC encoding could improve wave image quality, particularly at very high undersampling factors and in the context of limited wave amplitudes. These results were further supported by g-factor maps.
    CONCLUSIONS: Results show that FRONSAC can be used to improve image quality of wave at very high undersampling rates or in slew-limited acquisitions. Our study illustrates the potential of the proposed fast field mapping approach.
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  • 文章类型: Journal Article
    Talin将肌动球蛋白细胞骨架与整联蛋白偶联,并将张力传递至细胞外基质。Talin还与许多其他能够调节肌动蛋白-整联蛋白连接的蛋白质相互作用,从而与下游机械信号级联反应。这里,我们证明支架蛋白Caskin2通过其C端LD基序直接与talin的R8结构域相互作用。Caskin2还与WAVE调节复合物结合,以Abi1依赖性方式促进细胞迁移。此外,我们证明Caskin2-Abi1相互作用受生长因子诱导的丝氨酸878上Caskin2磷酸化调节。在MCF7和UACC893细胞中,包含CASKIN2的扩增,Caskin2定位于质膜相关斑块和CMSC的局灶性粘附周围。一起来看,我们的结果确定Caskin2是一种新的talin结合蛋白,它不仅可以连接整合素介导的粘附肌动蛋白聚合,但也可能在整合素和微管之间的串扰中发挥作用。
    Talin (herein referring collectively to talin 1 and 2) couples the actomyosin cytoskeleton to integrins and transmits tension to the extracellular matrix. Talin also interacts with numerous additional proteins capable of modulating the actin-integrin linkage and thus downstream mechanosignaling cascades. Here, we demonstrate that the scaffold protein Caskin2 interacts directly with the R8 domain of talin through its C-terminal LD motif. Caskin2 also associates with the WAVE regulatory complex to promote cell migration in an Abi1-dependent manner. Furthermore, we demonstrate that the Caskin2-Abi1 interaction is regulated by growth factor-induced phosphorylation of Caskin2 on serine 878. In MCF7 and UACC893 cells, which contain an amplification of CASKIN2, Caskin2 localizes in plasma membrane-associated plaques and around focal adhesions in cortical microtubule stabilization complexes. Taken together, our results identify Caskin2 as a novel talin-binding protein that might not only connect integrin-mediated adhesion to actin polymerization but could also play a role in crosstalk between integrins and microtubules.
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  • 文章类型: Journal Article
    骨吸收高度依赖于破骨细胞肌动蛋白细胞骨架的动态重排,以允许形成肌动蛋白环和功能性褶皱边界。Hem1是WAVE复合物的造血特异性亚基,可调节肌动蛋白聚合,对于造血细胞类型中的片状足形成至关重要。然而,其在破骨细胞分化和功能中的作用尚不清楚。这里,我们表明,虽然缺乏Hem1促进破骨细胞生成,Hem1-/-破骨细胞降解骨的能力严重受损。尽管体内破骨细胞数量增加,但体内Hem1的整体和破骨细胞特异性缺失显示股骨小梁骨量增加。我们发现,吸收缺陷源于Hem1缺乏的破骨细胞中富含肌动蛋白的密封区的形态变形和褶皱边界变形,导致囊泡运输受损和细胞内酸化增加。总的来说,我们的数据表明,Hem1通过调节皱褶边界的形成,从而调节破骨细胞的再吸收能力,在骨重建中发挥了未知的关键作用.
    Bone resorption is highly dependent on the dynamic rearrangement of the osteoclast actin cytoskeleton to allow formation of actin rings and a functional ruffled border. Hem1 is a hematopoietic-specific subunit of the WAVE-complex which regulates actin polymerization and is crucial for lamellipodia formation in hematopoietic cell types. However, its role in osteoclast differentiation and function is still unknown. Here, we show that although the absence of Hem1 promotes osteoclastogenesis, the ability of Hem1-/- osteoclasts to degrade bone was severely impaired. Global as well as osteoclast-specific deletion of Hem1 in vivo revealed increased femoral trabecular bone mass despite elevated numbers of osteoclasts in vivo. We found that the resorption defect derived from the morphological distortion of the actin-rich sealing zone and ruffled border deformation in Hem1-deficient osteoclasts leading to impaired vesicle transport and increased intracellular acidification. Collectively, our data identify Hem1 as a yet unknown key player in bone remodeling by regulating ruffled border formation and consequently the resorptive capacity of osteoclasts.
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  • 文章类型: Journal Article
    有充分的证据表明,大脑中有多个尺度和水平的波浪状活动。这种新兴的文献支持更广泛地采用大脑活动的波观点。具体来说,大脑状态可以描述为一组反复出现的,传播大脑活动的顺序模式,即波浪。我们研究了一组研究波状性质的实验工作。基于这些作品,我们使用跨时间和空间的尺度不可知框架,将大脑状态视为波。重点放在与大脑活动相关的顺序性和周期性上。最后,我们讨论了其含义,前景,和这个框架的实验机会。
    There is ample evidence of wave-like activity in the brain at multiple scales and levels. This emerging literature supports the broader adoption of a wave perspective of brain activity. Specifically, a brain state can be described as a set of recurring, sequential patterns of propagating brain activity, namely a wave. We examine a collective body of experimental work investigating wave-like properties. Based on these works, we consider brain states as waves using a scale-agnostic framework across time and space. Emphasis is placed on the sequentiality and periodicity associated with brain activity. We conclude by discussing the implications, prospects, and experimental opportunities of this framework.
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