Flexibility

灵活性
  • 文章类型: Journal Article
    Despite converging evidence of hierarchical organization in the cerebral cortex, with sensory-motor and association regions at opposite ends, the mechanism of such hierarchical interactions remains elusive. This organization was primarily investigated regarding the spatiotemporal dynamics of intrinsic connectivity networks (ICNs). However, more effort is needed to investigate network dynamics in the frequency domain. We aimed to examine the integrative role of brain regions in the frequency domain with graph metrics. Phase-based connectivity estimation was performed in three frequency bands (0.011-0.038, 0.043-0.071, and 0.076-0.103 Hz) in the BOLD signal during rest. We applied modularity analysis to connectivity matrices and investigated those areas, which we called integrative regions, that showed frequency-domain flexibility. Integrative regions, mostly belonging to attention networks, were densely connected to higher-order cognitive ICNs in lower frequency bands but to sensory-motor ICNs in higher frequency bands. We compared the normalized participation coefficient (Pnorm) values of integrative and core regions with respect to their relation to higher-order cognition using a permutation-based t-test for multiple linear regression. Regression parameters of integrative regions in relation to three cognitive scores in executive functions, and working memory were significantly larger than those of core regions (Pfdr < 0.05) for salience ventral attention network. Parameters of integrative regions in relation to intelligence scores were significantly larger than those with core regions (Pfdr < 0.05) in dorsal attention network. Larger parameters of neuropsychological test scores in relation to these flexible parcels further indicate their essential role at an intermediate level in behavior. Results emphasize the importance of frequency-band analysis of brain networks.
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  • 文章类型: Journal Article
    S-奥美拉唑和R-雷贝拉唑是用于治疗消化性疾病的重要质子泵抑制剂(PPI)。它们可以由Baeyer-Villiger单加氧酶(BVMO)催化的相应硫化物生物合成。在用于目标亚砜制备的BVMOs的开发过程中,立体选择性和过氧化程度是最重要的考虑因素。在本研究中,先前设计的LnPAMO-Mu15和嗜热菌的TtPAMO分别对硫醚具有较高的(S)和(R)构型立体选择性。发现TtPAMO能够分别将奥美拉唑硫化物(OPS)和雷贝拉唑硫化物(RPS)氧化为R-奥美拉唑和R-雷贝拉唑。然而,TtPAMO存在的过氧化问题限制了TtPAMO在亚砜生物合成中的应用。揭示了LnPAMO-Mu15和TtPAMO对OPS的不利立体选择性以及TtPAMO对OPS的过度氧化的结构机制,基于此,TtPAMO的合理设计侧重于催化位点附近回路的灵活性。筛选出变体TtPAMO-S482Y,其对OPS和RPS的过氧化程度最低,这是由于催化中心的柔性比TtPAMO降低。这项研究的成功不仅证明了本研究中提出的过氧化机理的合理性,而且为BVMOs向硫醚底物的发展提供了线索,用于相应的亚砜制备。
    S-omeprazole and R-rabeprazole are important proton pump inhibitors (PPIs) used for treating peptic disorders. They can be biosynthesized from the corresponding sulfide catalyzed by Baeyer-Villiger monooxygenases (BVMOs). During the development of BVMOs for target sulfoxide preparation, stereoselectivity and overoxidation degree are important factors considered most. In the present study, LnPAMO-Mu15 designed previously and TtPAMO from Thermothelomyces thermophilus showed high (S)- and (R)-configuration stereoselectivity respectively towards thioethers. TtPAMO was found to be capable of oxidating omeprazole sulfide (OPS) and rabeprazole sulfide (RPS) into R-omeprazole and R-rabeprazole respectively. However, the overoxidation issue existed and limited the application of TtPAMO in the biosynthesis of sulfoxides. The structural mechanisms for adverse stereoselectivity between LnPAMO-Mu15 and TtPAMO towards OPS and the overoxidation of OPS by TtPAMO were revealed, based on which, TtPAMO was rationally designed focused on the flexibility of loops near catalytic sites. The variant TtPAMO-S482Y was screened out with lowest overoxidation degree towards OPS and RPS due to the decreased flexibility of catalytic center than TtPAMO. The success in this study not only proved the rationality of the overoxidation mechanism proposed in this study but also provided hints for the development of BVMOs towards thioether substrate for corresponding sulfoxide preparation.
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  • 文章类型: Journal Article
    本研究成功制备了一种新型SA/BF/Gel复合导电水凝胶,具有粘合和自修复性能。通过深入研究,凝胶含量对拉伸的影响,粘合剂,自我修复特性,讨论了SA/BF/Gel复合导电水凝胶的导电性。还研究了材料的传感性能和传感机理,并对其潜在应用进行了初步探索。尝试将SA/BF/Gel复合导电水凝胶应用于3D打印技术,在水凝胶的流变特性与其打印结构之间建立联系。凝胶的加入显著提高了水凝胶的柔韧性,在1.5%的凝胶含量下,电导率高达3.12S/m。当用作传感器时,该材料表现出高灵敏度(GF=2.21)和优异的循环稳定性,渲染它适用于手指和手腕的弯曲运动的实时监测的广泛应用,以及水凝胶表面上的动态接触和接触力的变化。SA/BF/Gel复合导电水凝胶具有用于多种应用的潜力,包括智能可穿戴设备的开发,对个体的监控,以及人类和机器的融合。此外,与这种水凝胶相关的研究结果将为材料科学的发展和智能技术的整合提供坚实的基础。
    This study has been successfully developed the Sodium alginate/Bamboo fiber /Gelatin(SA/BF/Gel)composite conductive hydrogel with adhesive and self-healing properties. Through in-depth research, the influence of Gel content on the tensile, adhesive, self-healing properties, and conductivity of the SA/BF/Gel composite conductive hydrogel was discussed. The sensing performance and sensing mechanism of the material were also investigated, along with a preliminary exploration of its potential applications. An attempt was made to apply the SA/BF/Gel composite conductive hydrogel to 3D printing technology, establishing a connection between the rheological properties of the hydrogel and its printing structure. The addition of Gel significantly improved the flexibility of the hydrogel, with a conductivity of up to 3.12 S/m at a Gel content of 1.5 %. When employed as a sensor, the material exhibited high sensitivity (GF = 2.21) and excellent cyclic stability, rendering it suitable for a wide range of applications in real-time monitoring of bending movements of fingers and wrists, as well as dynamic contact and variations in contact forces on the hydrogel surface. The SA/BF/Gel composite conductive hydrogel has the potential to be utilized in a multitude of applications, including the development of smart wearable devices, the monitoring of individual human beings, and the integration of human beings and machines. Furthermore, the research findings associated with this hydrogel will provide a strong foundation for the advancement of materials science and the integration of smart technologies.
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  • 文章类型: Journal Article
    抗结冰/除冰涂层具有低能耗和优异的柔韧性,可以更好地满足实际工程中的应用要求。在本文中,制备了基于碳纳米材料的主动-被动集成防冰/除冰涂层,它不仅具有电热转换的各种功能,光热转换,和超疏水性,但也显示出适应弯曲表面的大变形能力。涂层由夹层结构的底部和顶层组成,前者包括由密集混合的碳纳米管(CNT)和石墨烯制成的芯导电层和两个聚二甲基硅氧烷(PDMS)包裹层,而后者是填充有TiN和SiO2纳米颗粒的聚合物复合材料。实验研究表明,当本涂层仅在电场下工作时,可以实现90%的电能转化为热能,只有2V的电压足以在400s内以负20度解冻表面,和2.5V的稍大的电压导致在200s内超过100°C的显着温度升高。这些所需的电压明显小于现有的基于电热的方法中的对应电压,以实现相同的加热效果,这可以进一步减少与阳光照明的辅助作用。因此,可以用小的能量输入实现快速和完全的除冰/除霜。此外,防水功能,电属性,涂层的电热转换性能在经过较大的弯曲变形或多次弯曲循环后几乎保持不变,从而确保在平面和曲面上的出色防冰/除冰效果。所有结果都证明了本发明涂层的明显优点,包括高效率,低能耗,全天候适应性,和出色的灵活性,这对于不同形状的工业设备的防冻保护具有重要的实用价值。
    Anti-icing/deicing coatings with low energy consumption and superior flexibility could better fit application requirements in practical engineering. In this paper, an active-passive-integrated anti-icing/deicing coating based on carbon nanomaterials is prepared, which not only possesses various functions of electrothermal conversion, photothermal conversion, and superhydrophobicity but also shows a large deformability to accommodate curved surfaces. The coating consists of a sandwich-structured bottom part and top layer, the former of which includes a core conductive layer made of densely mixed carbon nanotubes (CNTs) and graphene and two polydimethylsiloxane (PDMS) wrapping layers, while the latter is a polymeric composite filled with TiN and SiO2 nanoparticles. Experimental studies show that, when the present coating works under an electric field alone, a 90% conversion of electric energy to thermal energy can be realized, only a 2 V voltage is enough to unfreeze the surface at minus 20 degrees within 400 s, and a slightly larger voltage of 2.5 V leads to a significant temperature increase of more than 100 °C within 200 s. Such required voltages are significantly smaller than their counterparts in existing electrothermal-based methods to achieve the same heating effects, which could be further diminished with the auxiliary action of sunlight illumination. A fast and complete deicing/defrosting can be consequently achieved with a small energy input. Furthermore, the water repellency function, electric property, and electrothermal conversion performance of the coating remain almost unchanged after either a large bending deformation or many bending cycles, thus ensuring an outstanding anti-icing/deicing effect on both flat and curved surfaces. All of the results demonstrate apparent advantages of the present coating including high efficiency, low energy consumption, all-weather adaptability, and excellent flexibility, which should be of great practical value for the freeze protection of differently shaped industrial equipment.
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  • 文章类型: Journal Article
    前药纳米组装体结合了前药策略和纳米技术的优点,已被广泛用于递送抗肿瘤药物。这些前药通常包含活性药物模块,响应模块,和修改模块。其中,修饰模块是提高母体药物自组装能力的关键因素。然而,修饰模块的特定结构对前药自组装的影响仍然难以捉摸。在这项研究中,使用2-辛基-1-十二烷醇(OD)作为柔性修饰模块和胆固醇(CLS)作为刚性修饰模块开发了两种吉西他滨(GEM)前药。有趣的是,改性模块化学结构的差异显著影响组装性能,药物释放,细胞毒性,肿瘤积聚,前药纳米组装体的抗肿瘤功效。值得注意的是,用柔性修饰链(OD)构建的前药纳米组装体显示出改善的稳定性,更快的药物释放,和增强的抗肿瘤作用。我们的发现阐明了修饰模块对前药纳米组装体构建的重要影响。
    Prodrug nanoassemblies combine the advantages of prodrug strategies and nanotechnology have been widely utilized for delivering antitumor drugs. These prodrugs typically comprise active drug modules, response modules, and modification modules. Among them, the modification modules play a critical factor in improving the self-assembly ability of the parent drug. However, the impact of the specific structure of the modification modules on prodrug self-assembly remains elusive. In this study, two gemcitabine (GEM) prodrugs are developed using 2-octyl-1-dodecanol (OD) as flexible modification modules and cholesterol (CLS) as rigid modification modules. Interestingly, the differences in the chemical structure of modification modules significantly affect the assembly performance, drug release, cytotoxicity, tumor accumulation, and antitumor efficacy of prodrug nanoassemblies. It is noteworthy that the prodrug nanoassemblies constructed with flexible modifying chains (OD) exhibit improved stability, faster drug release, and enhanced antitumor effects. Our findings elucidate the significant impact of modification modules on the construction of prodrug nanoassemblies.
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  • 文章类型: Journal Article
    这篇简短的评论涵盖了一维材料的热电性能,如纳米线和纳米管。这些纳米结构材料的费米能级附近的电子态密度的高度局部化峰改善了塞贝克系数。此外,量子限制导致离散的能级和修改的态密度,潜在地增强导电性。这些电子效应,再加上Umklapp声子散射的优势,这降低了一维材料的热导率,可以实现前所未有的热电效率,在二维或散装材料。值得注意的进步包括碳和硅纳米管和Bi3Te2,Bi,ZnO,SiC,和Si1-xGex纳米线具有显著降低的热导率和增加的ZT。在所有这些纳米线和纳米管中,效率作为直径的函数进行了探索。在这些纳米材料中,碳纳米管提供机械灵活性和改进的热电性能。尽管碳纳米管理论上具有很高的导热性,由于其低维结构而导致的塞贝克系数的提高可以弥补这一点。关于灵活性,经济标准,易于制造,和体重,碳纳米管可能是热电发电的有希望的候选者。
    This brief review covers the thermoelectric properties of one-dimensional materials, such as nanowires and nanotubes. The highly localised peaks of the electronic density of states near the Fermi levels of these nanostructured materials improve the Seebeck coefficient. Moreover, quantum confinement leads to discrete energy levels and a modified density of states, potentially enhancing electrical conductivity. These electronic effects, coupled with the dominance of Umklapp phonon scattering, which reduces thermal conductivity in one-dimensional materials, can achieve unprecedented thermoelectric efficiency not seen in two-dimensional or bulk materials. Notable advancements include carbon and silicon nanotubes and Bi3Te2, Bi, ZnO, SiC, and Si1-xGex nanowires with significantly reduced thermal conductivity and increased ZT. In all these nanowires and nanotubes, efficiency is explored as a function of the diameter. Among these nanomaterials, carbon nanotubes offer mechanical flexibility and improved thermoelectric performance. Although carbon nanotubes theoretically have high thermal conductivity, the improvement of their Seebeck coefficient due to their low-dimensional structure can compensate for it. Regarding flexibility, economic criteria, ease of fabrication, and weight, carbon nanotubes could be a promising candidate for thermoelectric power generation.
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  • 文章类型: Journal Article
    一系列性状之间的表型共变可能会限制或促进物种内部和物种之间的多样化,然而,很少有研究对这种关系进行实证检验。在这项研究中,我们调查了颅面特征的表型协方差是否与仅在圣萨尔瓦多岛上发现的p鱼的适应性辐射的多样化有关,巴哈马(SSI)。辐射包括通才,多食性,和鳞屑食性物种。我们比较了表型变异和协变(即,P矩阵)介于(1)来自加勒比海邻近岛屿和河口的通才p鱼的异域种群之间,(2)SSIp鱼的异域湖泊种群只有通才,和(3)SSI湖种群在共生中含有全部辐射。此外,我们检查了在两个形态上最不同的辐射成员的两个独立实验室饲养的F2杂种杂交的P矩阵中观察到的模式,以推断导致SSI幼鱼颅面特征变化的潜在机制。我们发现,SSI异源通才群体的P矩阵表现出更高水平的平均性状相关性,约束,与其他加勒比岛屿上的同族通才种群和SSI上所有三个物种的同族种群相比,同时具有较低的灵活性。我们还记录了虽然许多颅面特征似乎是由加性遗传效应引起的,关键特征的变化,如头部深度,上颌骨长度,下颌长度可能是通过非加性遗传机制产生的。最终,这项研究表明,表型共变的差异显著有助于产生和维持生物多样性。
    Phenotypic covariation among suites of traits may constrain or promote diversification both within and between species, yet few studies have empirically tested this relationship. In this study, we investigate whether phenotypic covariation of craniofacial traits is associated with diversification in an adaptive radiation of pupfishes found only on San Salvador Island, Bahamas (SSI). The radiation includes generalist, durophagous, and lepidophagous species. We compared phenotypic variation and covariation (i.e., the P matrix) between (1) allopatric populations of generalist pupfish from neighboring islands and estuaries in the Caribbean, (2) SSI pupfish allopatric lake populations with only generalist pupfish, and (3) SSI lake populations containing the full radiation in sympatry. Additionally, we examine patterns observed in the P matrices of two independent lab-reared F2 hybrid crosses of the two most morphologically distinct members of the radiation to make inferences about the underlying mechanisms contributing to the variation in craniofacial traits in SSI pupfishes. We found that the P matrix of SSI allopatric generalist populations exhibited higher levels of mean trait correlation, constraints, and integration with simultaneously lower levels of flexibility compared to allopatric generalist populations on other Caribbean islands and sympatric populations of all three species on SSI. We also document that while many craniofacial traits appear to result from additive genetic effects, variation in key traits such as head depth, maxilla length, and lower jaw length may be produced via non-additive genetic mechanisms. Ultimately, this study suggests that differences in phenotypic covariation significantly contribute to producing and maintaining organismal diversity.
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  • 文章类型: Journal Article
    诸如“许多”和“很少”之类的量词的处理依赖于数字知识,语言能力,和工作记忆。负量词(例如,“很少,\"\"不到一半\")导致比积极的同行更高的处理成本。此外,一些量词的含义是灵活的,因此可以适应。重要的是,在神经典型个体中,改变一个量词的含义也会导致其极性相反的含义发生广义变化(例如,“多”含义的变化导致“少”)含义的变化。这里,我们将这项研究扩展到中风后流利和非流利的失语症患者。在两个实验中,参与者听到了以下类型的句子:“许多/少数圆圈是黄色/蓝色的,“每张图片后面都有不同数量的蓝色和黄色圆圈。参与者判断句子是否充分描述了图片。每个实验由三个模块组成:一个基线模块,用于评估参与者的两个量词的标准,一个训练块,用于改变“许多,\"和一个测试块,与基线相同,以捕获量词语义的任何变化。在实验1中,“许多”的含义的变化是通过适应命名颜色的小数目(20-50%)的圆圈来引起的。在实验2中,每个响应率比例为40%(或更高)后,在训练块中给出了明确的反馈,“而40%通常被评为”很少。“目的是确定患有流利或非流利失语症的人是否能够适当地处理量词,以及脑损伤后是否存在广义语义灵活性。21名患者中有16名能够执行该任务。流利的失语症患者在反应时间内表现出预期的极性效应,并将“许多”的标准转变为“少数”,并将其概括为未经训练的量词。\"这个效果,然而,仅在明确反馈后获得(实验2),而不仅仅是通过适应(实验1)。相比之下,在这两个实验中,非流利失语症患者的量词语义都没有改变.这项研究有助于获得对失语症患者的量词处理和语义灵活性以及一般潜在处理机制的新见解。
    Processing of quantifiers such as \"many\" and \"few\" relies on number knowledge, linguistic abilities, and working memory. Negative quantifiers (e.g., \"few,\" \"less than half\") induce higher processing costs than their positive counterparts. Furthermore, the meaning of some quantifiers is flexible and thus adaptable. Importantly, in neurotypical individuals, changing the meaning of one quantifier also leads to a generalized change in meaning for its polar opposite (e.g., the change of the meaning of \"many\" leads to the change of that of \"few\"). Here, we extended this research to patients with fluent and non-fluent aphasia after stroke. In two experiments, participants heard sentences of the type \"Many/few of the circles are yellow/blue,\" each followed by a picture with different quantities of blue and yellow circles. The participants judged whether the sentence adequately described the picture. Each experiment consisted of three blocks: a baseline block to assess the participants\' criteria for both quantifiers, a training block to shift the criteria for \"many,\" and a test block, identical to the baseline to capture any changes in quantifier semantics. In Experiment 1, the change of the meaning of \"many\" was induced by using adaptation to small numbers (20-50%) of circles of the named color. In Experiment 2, explicit feedback was given in the training block after each response to rate proportions of 40% (or higher) as \"many,\" whereas 40% is normally rather rated as \"few.\" The objective was to determine whether people with fluent or non-fluent aphasia were able to process quantifiers appropriately and whether generalized semantic flexibility was present after brain damage. Sixteen out of 21 patients were able to perform the task. People with fluent aphasia showed the expected polarity effect in the reaction times and shifted their criteria for \"many\" with generalization to the untrained quantifier \"few.\" This effect, however, was only obtained after explicit feedback (Experiment 2) but not by mere adaptation (Experiment 1). In contrast, people with non-fluent aphasia did not change the quantifier semantics in either experiment. This study contributes to gaining new insights into quantifier processing and semantic flexibility in people with aphasia and general underlying processing mechanisms.
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  • 文章类型: Journal Article
    已知几种虫媒病毒病是地方性的(例如,克里米亚-刚果出血热,裂谷热)或正在出现(登革热,基孔肯雅,O\'nyong-nyong)在毛里塔尼亚的人口中,而其他一些在最近几年变得罕见(例如黄热病)。此外,家畜,尤其是牛,骆驼,山羊,羊,也已知感染了一些虫媒病毒(例如克里米亚-刚果出血热,裂谷热)。由于这些原因,毛里塔尼亚的病毒性出血热监测是综合疾病监测和反应(IDSR)的一部分。然而,关于毛里塔尼亚阿萨巴地区病毒性出血热监测系统有效性的信息有限.本研究的目的是评估监测系统的性能,特别是它的一般效用,简单,灵活性,可接受性,和反应性。
    2022年7月至8月在阿萨巴地区进行了描述性横断面研究,目的是通过采访参与病毒性出血热监测的关键参与者来评估系统的特征,重点是裂谷热和克里米亚-刚果出血热,使用按照疾病控制和预防中心(亚特兰大,格鲁吉亚,美国)。分析了国家公共卫生实验室研究所2020-2022年病毒性出血热的数据。Medians,四分位数范围,和比例使用EpiInfo®7.2.5.0和Excel®2021计算。
    调查问卷由阿萨巴地区病毒性出血热监测系统的所有26人回答。大多数受访者认为该系统有用(51%),简单(63%),可接受(46%),反应灵敏(64%),灵活(46%)。对数据的分析显示,裂谷热的阳性预测值为28%。wilaya地区的每周病例分布表明,Kiffa的moughataa在9月记录了最多的病例,在2020年当月出现明显的每周高峰。根据国家公共卫生研究所数据库的分析,病毒性出血热病例得到迅速处理。调查答复和数据库分析揭示了与数据质量和数据管理机制有关的问题。监测系统的这些限制很可能是由于资源和人员培训不足,特别是在数据收集和管理方面,这反过来又导致不完整或丢失的数据和无效的数据输入。这些弱点可以归因于,至少在某种程度上,财政限制和对虫媒病毒疾病的优先权归属不足。尽管有这些限制,监测系统生成的疾病数据通常是可靠的。
    阿萨巴地区的病毒性出血热监测系统坚持国家病毒性出血热监测系统的组织和功能,这是IDSR的一部分。效用的特点,简单,响应性、响应性病毒性出血热监测系统的灵活性很好,但是可接受性和灵活性需要进一步提高。发现第一例人类或动物虫媒病毒病例越早,更有可能组织积极的干预措施,以应对新出现的流行病或流行病,并防止疾病的传播。有效的病毒监测系统是减少阿萨巴地区虫媒病毒病负面影响的关键。
    Several arboviral diseases have been known to be endemic (e.g., Crimean-Congo hemorrhagic fever, Rift Valley fever) or are emerging (dengue fever, chikungunya, O\'nyong-nyong) in human populations in Mauritania, while others have become rare in recent years (e.g. yellow fever). Moreover, domestic animals, especially cattle, camels, goats, and sheep, are also known to be infected with some of these arboviruses (e.g. Crimean-Congo hemorrhagic fever, Rift Valley fever). For these reasons, viral hemorrhagic fever surveillance in Mauritania is part of the Integrated Disease Surveillance and Response (IDSR). However, limited information is available on the efficacy of the viral hemorrhagic fever surveillance system in the Assaba region of Mauritania. The aim of the present study was to assess the performance of the surveillance system, in particular its general utility, simplicity, flexibility, acceptability, and reactivity.
    A descriptive cross-sectional study was conducted from July to August 2022 in the Assaba region with the objective of evaluating the characteristics of the system by interviewing key actors involved in the surveillance of viral hemorrhagic fevers, with a focus on Rift Valley fever and Crimean-Congo hemorrhagic fever, using questionnaires developed following the guidelines of the Centers for Disease Control and Prevention (Atlanta, Georgia, USA). Data from 2020-2022 on viral hemorrhagic fevers from the National Institute of Public Health laboratory were analyzed. Medians, interquartile ranges, and proportions were calculated using Epi Info® 7.2.5.0 and Excel® 2021.
    The questionnaire was answered by all twenty-six persons involved in the viral hemorrhagic fever surveillance system in Assaba region. The majority of survey respondents found the system to be useful (51%), simple (63%), acceptable (46%), responsive (64%), and flexible (46%). An analysis of the data revealed a positive predictive value of 28% for Rift Valley Fever. The weekly distribution of cases within the wilaya indicates that the moughataa of Kiffa recorded the highest number of cases in September, with a notable weekly peak during that month in 2020. According to the analysis of the National Institute of Public Health database, cases of viral hemorrhagic fevers were promptly handled. Survey responses and database analysis revealed issues related to data quality and data management mechanisms. These limitations in the surveillance system are likely to be due to insufficient resources and training of the personnel, in particular with regards to data collection and management, which in turn led to incomplete or missing data and invalid data entry. These weak points can be ascribed, at least in part, to financial constraints and inadequate attribution of priority to arboviral diseases. Despite these limitations, disease data generated by the surveillance system were generally reliable.
    The viral hemorrhagic fever surveillance system in the Assaba region adheres to the organization and functioning of the national viral hemorrhagic fever surveillance system, which is part of the IDSR. The characteristics of utility, simplicity, responsiveness, and flexibility of the viral hemorrhagic fever surveillance system are good, but acceptability and flexibility need further improvement. The earlier the first arboviral human or animal cases are detected, the more likely an active intervention can be organized in response to the emerging epidemic or epizootic and prevent the spread of the disease. An efficient viral surveillance system is the key to reducing the negative impact of arboviral diseases in Assaba region.
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    石墨,资源丰富,成本低,被认为是钾离子电池(PIBs)的有前途的负极材料。然而,因为钾离子的体积很大,石墨夹层之间钾的嵌入/脱嵌导致其巨大的体积膨胀,导致循环稳定性和倍率性能差。在这里,采用自传播还原策略来制造柔性,自支撑3D多孔石墨@还原氧化石墨烯(3D-G@rGO)复合膜用于PIBs。3D多孔网络不仅可以有效地减轻石墨中的体积膨胀,而且可以为钾储存提供许多活性位点,并允许电解质渗透和快速离子迁移。因此,与原始石墨阳极相比,柔性3D-G@rGO薄膜电极表现出大大提高的K存储性能,在0.1C时的可逆容量为452.8mAhg-1,100次循环后的容量保持率为80.4%。它还具有出色的倍率性能,在2和5C下保持139.1和94.2mAhg-1的高比容量,分别。提出的自蔓延还原策略构建三维自支撑结构是提高石墨阳极结构稳定性和储钾性能的可行途径。
    Graphite, with abundant resources and low cost, is regarded as a promising anode material for potassium-ion batteries (PIBs). However, because of the large size of potassium ions, the intercalation/deintercalation of potassium between the interlayers of graphite results in its huge volume expansion, leading to poor cycling stability and rate performance. Herein, a self-propagating reduction strategy is adopted to fabricate a flexible, self-supporting 3D porous graphite@reduced graphene oxide (3D-G@rGO) composite film for PIBs. The 3D porous network can not only effectively mitigate the volume expansion in graphite but also provide numerous active sites for potassium storage as well as allow for electrolyte penetration and rapid ion migration. Therefore, compared to the pristine graphite anode, the flexible 3D-G@rGO film electrode exhibits greatly improved K-storage performance with a reversible capacity of 452.8 mAh g-1 at 0.1 C and a capacity retention rate of 80.4% after 100 cycles. It also presents excellent rate capability with a high specific capacity of 139.1 and 94.2 mAh g-1 maintained at 2 and 5 C, respectively. The proposed self-propagating reduction strategy to construct a three-dimensional self-supporting structure is a viable route to improve the structural stability and potassium storage performance of graphite anodes.
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