VFT

VFT
  • 文章类型: Journal Article
    混合固体电解质(HSE)旨在将无机填料的优异离子电导率与聚合物电解质的可扩展过程结合在固态电池的独特材料中。追求优化关键指标的目标(在25°C和自立特性下σ离子≥10-4S·cm-1),我们成功开发了一种基于改性聚(环氧乙烷)的HSE:LiTFSI有机基质,将高负载(75重量%)的Li6PS5Cl颗粒结合在一起,遵循无溶剂路线。对可用配方参数的合理研究使我们能够了解每种成分在电导率中的作用,混合,和机械内聚力。尤其是,激活机制的类型(Arrhenius或Vogel-Fulcher-Tammann(VFT))及其相关能量被提出作为揭示HSE内部离子途径的新指标。我们表明,聚合物在陶瓷方法是强制性的,以获得增强的传导通过HSE陶瓷网络,以及优越的机械性能,通过拉伸试验显示。探索阶段的兼容性,使用电化学阻抗谱(EIS)和7Li核磁共振(NMR),揭示了中间相的形成,其数量和电阻率随时间和温度而增长。最后,通过组装基于HSE的电池来评估电化学性能,它显示出与纯陶瓷相当的稳定性,但仍然遭受较高的极化和因此较低的容量。总之,我们希望这些发现为开发成功的HSE提供有价值的知识,通过将正确指标的优化放在公式的核心。
    Hybrid solid electrolytes (HSEs) aim to combine the superior ionic conductivity of inorganic fillers with the scalable process of polymer electrolytes in a unique material for solid-state batteries. Pursuing the goal of optimizing the key metrics (σion ≥ 10-4 S·cm-1 at 25 °C and self-standing property), we successfully developed an HSE based on a modified poly(ethylene oxide):LiTFSI organic matrix, which binds together a high loading (75 wt %) of Li6PS5Cl particles, following a solvent-free route. A rational study of available formulation parameters has enabled us to understand the role of each component in conductivity, mixing, and mechanical cohesion. Especially, the type of activation mechanism (Arrhenius or Vogel-Fulcher-Tammann (VFT)) and its associated energy are proposed as a new metric to unravel the ionic pathway inside the HSE. We showed that a polymer-in-ceramic approach is mandatory to obtain enhanced conduction through the HSE ceramic network, as well as superior mechanical properties, revealed by the tensile test. Probing the compatibility of phases, using electrochemical impedance spectroscopy (EIS) alongside 7Li nuclear magnetic resonance (NMR), reveals the formation of an interphase, the quantity and resistivity of which grow with time and temperature. Finally, electrochemical performances are evaluated by assembling an HSE-based battery, which displays comparable stability as pure ceramic ones but still suffers from higher polarization and thus lower capacity. Altogether, we hope these findings provide valuable knowledge to develop a successful HSE, by placing the optimization of the right metrics at the core of the formulation.
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  • 文章类型: Journal Article
    摘要与天体生物学相关的笔记本电脑交付的360度沉浸式虚拟现场旅行(VFTs)越来越多地用于高等教育。然而,关于教学法的经验,以及在实现预期结果方面什么有效和什么无效,文献仍然很少。部分原因是,在时间和金钱上限制了制作这种教育上有前途的VFT的成本,但是各种举措正在解决这两个限制因素。因此,支撑这种VFT的教学方面在很大程度上仍未被探索。我们为一个吸引全球研究人员兴趣的天体生物场站点-西澳大利亚的皮尔巴拉克拉通进行了360度VFT的实验,世界上保存最完好和最有说服力的地球早期生命证据存在的地方,从34.8亿年前开始。我们的挑战是让最后一年的本科理科学生——几乎没有地质背景——在不参观的情况下接触这个现场,因为位置偏远,安全考虑,和成本。另一个考虑因素是VFT所在的天体生物学课程完全在线,所以目前不在澳大利亚居住的学生可以报名,增加了野外工作的实际后勤问题。我们介绍了我们在六年的数据中的经验,其中一项教学方式的变化比其他所有方面都突出-为VFT引入了手写的现场笔记本,这表明这是与现场相关的VFT的关键教学考虑因素。
    Abstract Astrobiology-related laptop-delivered 360-degree immersive Virtual Field Trips (VFTs) are increasingly used in higher education. However, the literature remains sparse on the experiences in approach to pedagogy and what works and what does not in attaining the intended outcomes. Part of the reason for that has been the limitation on the cost of making this educationally promising type of VFT in terms of time and money, but various initiatives are addressing these two limiting factors. Thus, the pedagogical aspects underpinning making this type of VFT remain largely unexplored. We experimented with the 360-degree VFTs for an astrobiological field site that attracts global researcher interest-the Pilbara Craton of Western Australia, where the world\'s best preserved and most convincing evidence of early life on Earth exists, from 3.48 billion years ago. Our challenge was to engage final-year undergraduate science students-with little to no geology background-with this field site without visiting it, because of the remote location, safety considerations, and cost. Another consideration was that the astrobiology course in which the VFT resides is fully online, so students not currently residing in Australia can enroll, adding to practical logistical problems for field work. We present our experiences over six years of data in which one pedagogical change stood out above all others-introducing a handwritten field notebook for a VFT-suggesting that it is a key pedagogical consideration for field-related VFTs.
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  • 文章类型: Journal Article
    功能近红外光谱(fNIRS)通过评估皮质血液动力学功能来鉴定精神疾病之间的神经生理学差异。很少有试验研究首发药物初治抑郁症患者(FMD)和复发性重度抑郁症(RMD)之间脑功能活动的差异。我们旨在确定FMD和RMD在氧合血红蛋白浓度([oxy-Hb])中的差异,探讨额颞叶皮层激活与临床症状的相关性。
    我们招募了40名FMD患者,53与RMD,和2021年5月至2022年4月的38名健康对照(HCs)。使用24项汉密尔顿抑郁量表(HAM-D)和汉密尔顿焦虑量表(HAM-A)评估症状严重程度。52通道fNIRS测量了VFT性能期间[oxy-Hb]的变化。
    两组患者在VFT任务期间的表现均低于HC(FDRp<0.05),但是两组患者之间没有显着差异。方差分析显示,与HC相比,MDD组的额叶和颞叶的平均[oxy-Hb]激活均较低(FDRp<0.05)。此外,与FMD患者相比,RMD患者的右背外侧前额叶皮质(DLPFC)和背额叶皮质(DFPC)的血流动力学反应显着降低(FDRp<0.05)。在平均[oxy-Hb]的变化与病史或临床症状之间没有发现显着相关性(FDRp<0.05)。
    在FMD和RMD患者的某些相同大脑区域中存在不同的神经功能活动,这意味着额叶区域的复杂性激活水平与MDD的分期之间存在联系。在MDD发作开始时可能已经存在认知障碍。
    www.chictr.org.cn,标识符ChiCTR2100043432。
    UNASSIGNED: Functional near-infrared spectroscopy (fNIRS) identifies neurophysiological differences between psychiatric disorders by assessing cortical hemodynamic function. Few trials have studied differences in brain functional activity between first-episode medication-naïve depression patients (FMD) and recurrent major depression (RMD). We aimed to determine the differences between FMD and RMD in oxygenated hemoglobin concentration ([oxy-Hb]), and to investigate the correlation between frontotemporal cortex activation and clinical symptoms.
    UNASSIGNED: We recruited 40 patients with FMD, 53 with RMD, and 38 healthy controls (HCs) from May 2021 to April 2022. Symptom severity was assessed with the 24-item Hamilton Depression Rating Scale (HAM-D) and the Hamilton Anxiety Rating Scale (HAM-A). A 52-channel fNIRS measured changes in [oxy-Hb] during VFT performance.
    UNASSIGNED: Both patient groups performed poorly during the VFT task compared with HC (FDR p < 0.05), but there was no significant difference between the two patient groups. Analysis of variance showed that mean [oxy-Hb] activation was lower in both the frontal and temporal lobes in the MDD group compared with HCs (FDR p < 0.05). Additionally, patients with RMD had a significantly lower hemodynamic response in the right dorsolateral prefrontal cortex (DLPFC) and dorsal frontal pole cortex (DFPC) than patients with FMD (FDR p < 0.05). No significant correlation was found between changes in mean [oxy-Hb] and either medical history or clinical symptoms (FDR p < 0.05).
    UNASSIGNED: The presence of different neurofunctional activity in some of the same brain regions in FMD and RMD patients implied a link between the level of complexity activation in frontal regions and the stage of MDD. Cognitive impairment may already be present at the beginning of an MDD episode.
    UNASSIGNED: www.chictr.org.cn, identifier ChiCTR2100043432.
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  • 文章类型: Journal Article
    背景:认知功能障碍是精神障碍的常见临床特征。许多功能近红外光谱(fNIRS)研究表明,精神分裂症(SZ)和重度抑郁症(MDD)的言语流畅性任务(VFT)期间前额叶激活减少。然而,没有研究检查和比较伦敦塔(TOL)期间的大脑激活模式,这是另一个经典,高灵敏度执行功能测试工具,这两种严重的精神障碍。这项研究旨在评估SZ和MDD患者在两种不同认知任务期间的大脑激活特征。方法:本研究招募了30例SZ患者,30例MDD患者,和30名人口统计学匹配的健康对照(HCs)。在执行TOL任务和VFT任务期间,使用32通道fNIRS测量前额叶皮层(PFC)的血液动力学变化。结果:SZ患者的VFT表现比MDD患者和HC患者差,两组患者的TOL表现低于HC。与HC相比,两组患者在广泛性PFC中的激活均显著降低.特别是在背外侧PFC(DLPFC)的某些通道中,SZ患者的血流动力学变化明显低于MDD患者。结论:SZ和MDD患者在两种认知任务过程中,不同认知域的损害程度不同,脑激活模式不同。需要进一步的研究来确定fNIRS在临床评估和诊断中的用途。
    Background: Cognitive dysfunction is a common clinical feature of mental disorders. A number of functional near-infrared spectroscopy (fNIRS) studies have shown reduced prefrontal activation during the verbal fluency task (VFT) in schizophrenia (SZ) and major depressive disorder (MDD). However, no studies have examined and compared the brain activation patterns during the Tower of London (TOL), which is another classic, high-sensitivity executive function testing tool, in these two serious mental disorders. This study aimed to assess the characteristics of brain activation during the two different cognitive tasks in SZ and MDD patients. Methods: This study recruited 30 patients with SZ, 30 patients with MDD, and 30 demographically matched healthy controls (HCs). The hemodynamic changes of the prefrontal cortex (PFC) were measured using 32-channel fNIRS during performance of the TOL task and VFT task. Results: SZ patients showed poorer VFT performance than MDD patients and HCs, and the two patient groups showed poorer TOL performance than HCs. Compared to HCs, both of the patient groups exhibited a significant decreased activation in the extensive PFC. Particularly in certain channels in the dorsolateral PFC (DLPFC), SZ patients exhibited significantly decreased hemodynamic changes than the MDD patients. Conclusions: Patients with SZ and MDD have different levels of impairment in different cognitive domains and different patterns of brain activation during the two cognitive tasks. Further research is needed to determine the use of fNIRS for clinical evaluation and diagnosis.
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  • 文章类型: Evaluation Study
    旨在研究单词生成的功能磁共振成像(fMRI)范例传统上使用计算机步调版本的语言流畅性任务(VFT),其中包括单词生成的“块”和基线单词重复任务。尚未系统地研究上述节奏的VFT范式在区分神经精神病患者与健康受试者中的实用性。我们管理了一个计算机化的,语义VFT的节奏版本,包括24名精神分裂症和24名匹配的健康受试者的单词生成和单词重复块,在fMRI采集之前和期间。在计算机节奏语义VFT的“扫描前”和“扫描内”会话中,精神分裂症患者的表现均明显不如健康对照受试者。具体来说,精神分裂症患者产生的总反应(VFTR)和正确反应(VFCR)显着减少,但有更多的“无响应”试验。然而,在扫描前或"扫描内"会话中,持续性反应无显著组间差异.我们先前已经报道了上述计算机化任务,以生成具有血液动力学相关性的行为表现指数(John等人。,2011).因此,我们的研究结果支持在临床和研究环境中使用包括单词生成和单词重复块的计算机化有节奏VFT.
    Functional magnetic resonance imaging (fMRI) paradigms designed to study word generation traditionally utilize a computerized paced version of the verbal fluency task (VFT) comprising \'blocks\' of word generation and a baseline word repetition task. The utility of the above paced VFT paradigm in differentiating neuropsychiatric patients from healthy subjects has not been systematically examined. We administered a computerized, paced version of the semantic VFT comprising word generation and word repetition blocks to 24 schizophrenia and 24 matched healthy subjects, both before and during fMRI acquisition. The performance of patients with schizophrenia was significantly inferior to that of healthy control subjects in both the \'pre-scan\' and \'intra-scan\' sessions of the computerized paced semantic VFT. Specifically, schizophrenia patients generated significantly fewer total responses (VFTR) as well as correct responses (VFCR), but a larger number of \'no response\' trials. However, there were no significant group differences in perseverative responses in the pre-scan session or \'intra-scan\' sessions. The above computerized task has been reported by us previously to generate a behavioral performance index with hemodynamic correlates (John et al., 2011). Thus, our findings support the use of computerized paced VFT comprising word generation and word repetition blocks in both clinical and research settings.
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  • 文章类型: Journal Article
    Two types of verbal fluency tasks (letter fluency task; LFT, category fluency task; CFT) have been widely used to assess cognitive function in people with psychiatric diseases including schizophrenia. The task demand of the LFT is considered to vary across languages, as the cognitive process largely relies on sound and writing systems. Specifically, a sound unit for a letter (s) and a manner of association between them are assumed to be related with the performance. In the current study, three analyses have been conducted to examine this issue, using Japanese, Turkish, and English-speaking patients with schizophrenia. It was hypothesized that severity of letter fluency impairment would be in the order of Japanese, Turkish, and English speaking patients according to the inflexibility of a word search. First, performance on the LFT and the CFT was compared among Japanese (N=40), Turkish (N=30), and the US (N=31) patients (Analysis 1). A significant difference was found between the US and other two groups only in the LFT. Second, verbal fluency performance was compared between Japanese and Turkish patients by contrasting the degree of disassociations from normal controls (Japanese: N=20, Turkish: N=30) (Analysis 2). In Japanese patients, performance on the LFT was more severely impaired compared to that on the CFT while the opposite trend was found in the Turkish counterpart, suggesting that letter fluency performance was more degraded in Japanese patients. Finally, Analysis 3 was conducted to examine the relative order of letter fluency impairment among Japanese, Turkish and English-speaking patients. Disassociation in English users with schizophrenia was estimated based on previous meta-analytic reviews. The effect size (ES) for the letter fluency deficit was the largest in the Japanese sample, while the other two groups share similar ESs. The results from the three analyses partially supported the hypothesis for the severity of the letter fluency impairment in patients with schizophrenia. The language-dependency of letter fluency impairment was thought to be explained by the theoretical model built on unique properties of sound and writing systems. The considerations presented here would provide useful information for optimizing the portability of cognitive tasks across languages.
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  • 文章类型: Journal Article
    背景:未经治疗的精神病(DUP)的持续时间已被证明与精神分裂症的短期和长期结局不良相关。即便如此,很少有研究使用功能神经影像学来研究精神分裂症中的DUP。在本研究中,我们使用近红外光谱(NIRS)研究了DUP对精神分裂症患者言语流畅性测试(VFT)时脑功能的影响.
    方法:共纳入62例精神分裂症患者。他们被分为短期治疗(≤6个月,n=33)或长期治疗(>6个月,n=29)组基于其治疗持续时间。使用多通道NIRS测量VFT期间额颞区的血液动力学变化。我们检查了每组DUP和血液动力学变化之间的关联,以探索DUP在不同治疗持续时间对大脑皮层活动的不同影响。
    结果:在长期治疗组中,我们发现在较长的DUP和大约在左额下回的皮质活动减少之间存在显著关联,左额中回,左中央后回,右中前回,双侧颞上回,和双侧颞中回,而在短期治疗组中未观察到DUP与大脑皮层活动之间的关联。
    结论:我们的研究结果表明,长期DUP时间延长可能与额颞区皮质活动水平降低有关。早期发现和干预缩短DUP的精神病可能有助于改善精神分裂症患者的长期预后。
    BACKGROUND: Duration of untreated psychosis (DUP) has been shown to be associated with both poor short-term and long-term outcomes in schizophrenia. Even so, few studies have used functional neuroimaging to investigate DUP in schizophrenia. In the present study, we used near-infrared spectroscopy (NIRS) to investigate the influence of DUP on brain functions during a verbal fluency test (VFT) in patients with schizophrenia.
    METHODS: A total of 62 patients with schizophrenia were included. They were categorized into either short treatment (≤6months, n=33) or long treatment (>6months, n=29) groups based on their duration of treatment. Hemodynamic changes over the frontotemporal regions during a VFT were measured using multi-channel NIRS. We examined the associations between DUP and hemodynamic changes in each group to explore if there were different effects of DUP on brain cortical activity at different treatment durations.
    RESULTS: In the long treatment group, we found significant associations between a longer DUP and decreased cortical activity approximately at the left inferior frontal gyrus, left middle frontal gyrus, left postcentral gyrus, right precentral gyrus, bilateral superior temporal gyrus, and bilateral middle temporal gyrus, whereas no associations between DUP and brain cortical activity were observed in the short treatment group.
    CONCLUSIONS: Our results indicated that longer DUP may be associated with decreased level of cortical activities over the frontotemporal regions in the long-term. Early detection and intervention of psychosis that shortens DUP might help to improve the long-term outcomes in patients with schizophrenia.
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  • 文章类型: Journal Article
    早期生长反应3(EGR3)基因是在整个大脑中表达的即时早期基因,已被认为是精神分裂症(SZ)的潜在易感基因。EGR3损伤与各种神经发育障碍有关,一些动物研究报道了EGR3在前额叶皮层中的作用。因此,EGR3基因型变异可能反映在前额叶功能上。通过在成像遗传学方法中使用多通道近红外光谱(NIRS),我们在SZ患者的认知任务中测试了EGR3基因多态性与前额叶血流动力学反应之间的关联.我们评估了73例SZ和73岁的慢性患者,性别-,和提供书面知情同意书的基因型匹配的健康对照(HC)。我们使用NIRS来测量言语流利任务(VFT)的字母版本中前额氧合血红蛋白浓度(oxyHb)的变化。在EGR3基因型亚组(rs35201266,GG/GA/AA)之间进行统计比较。与GG和GA基因型组相比,在VFT期间,AA基因型组显示左背外侧前额叶皮层(DLPFC)的oxyHb增加明显较小;对于SZ和HC患者都是如此。我们的发现提供了体内人类证据,证明EGR3多态性对健康成年人和SZ患者的前额叶血流动力学激活水平有显着影响。EGR3的遗传变异可能通过神经发育影响前额叶功能。这项研究说明了NIRS在精神疾病的影像学遗传学研究中的有用性。
    The early growth response 3 (EGR3) gene is an immediate early gene that is expressed throughout the brain and has been suggested as a potential susceptibility gene for schizophrenia (SZ). EGR3 impairment is associated with various neurodevelopmental dysfunctions, and some animal studies have reported a role for EGR3 function in the prefrontal cortex. Therefore, EGR3 genotype variation may be reflected in prefrontal function. By using multi-channel near-infrared spectroscopy (NIRS) in an imaging genetics approach, we tested for an association between the EGR3 gene polymorphism and prefrontal hemodynamic response during a cognitive task in patients with SZ. We assessed 73 chronic patients with SZ and 73 age-, gender-, and genotype-matched healthy controls (HC) who provided written informed consent. We used NIRS to measure changes in prefrontal oxygenated hemoglobin concentration (oxyHb) during the letter version of a verbal fluency task (VFT). Statistical comparisons were performed among EGR3 genotype subgroups (rs35201266, GG/GA/AA). The AA genotype group showed significantly smaller oxyHb increases in the left dorsolateral prefrontal cortex (DLPFC) during the VFT than the GG and GA genotype groups; this was true for both patients with SZ and HC. Our findings provide in vivo human evidence of a significant influence of EGR3 polymorphisms on prefrontal hemodynamic activation level in healthy adults and in patients with SZ. Genetic variation in EGR3 may affect prefrontal function through neurodevelopment. This study illustrates the usefulness of NIRS in imaging genetics investigations on psychiatric disorders.
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  • 文章类型: Journal Article
    Insight has been studied mostly from a clinical perspective. Recently, the focus of this research field shifted to cognitive insight or the ability to monitor and correct the erroneous convictions of individuals. In this study, we investigated the relationship between cognitive insight and prefrontal function during a cognitive task in 30 patients with clinically stable schizophrenia and 30 age- and gender-matched healthy controls. We measured the changes in hemoglobin concentration in the prefrontal and temporal cortical regions during a verbal fluency task (VFT) by using 52-channel near-infrared spectroscopy (NIRS). Cognitive insight was measured using the Beck Cognitive Insight Scale (BCIS). Regional hemodynamic changes were significantly smaller in the schizophrenia group than in the control group in prefrontal and temporal regions, and significant positive relationship was observed between the score of the BCIS self-reflectiveness subscale and right ventrolateral prefrontal and right temporal functions during the VFT. These results suggest that the right ventrolateral prefrontal and temporal cortical regions are associated with cognitive insight in clinically stable patients with schizophrenia and that NIRS is an efficient medical tool for monitoring these characteristics.
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  • 文章类型: Journal Article
    BACKGROUND: Ganglionated plexi (GP) ablation has been shown to play an important role in atrial fibrillation (AF) initiation and maintenance. Also, GP ablation increases chances for prevention of AF recurrence. This study investigated the effects of GP ablation on ventricular electrophysiological properties in normal dog hearts and after acute myocardial ischemia (AMI).
    METHODS: Fifty anesthetized dogs were assigned into normal heart group (n=16) and AMI heart group (n=34). Ventricular dynamic restitution, effective refractory period (ERP), electrical alternans and ventricular fibrillation threshold (VFT) were measured before and after GP ablation in the normal heart group. In the AMI heart group, the incidence of ventricular arrhythmias and VFT were determined.
    RESULTS: In the normal heart group, GP ablation significantly prolonged ERP, facilitated electrical alternans but did not increase ERP dispersion, the slope of restitution curves and its spatial dispersion. Also, GP ablation did not cause significant change of VFT. In the AMI heart group, the incidence of ventricular arrhythmias after GP ablation was significantly higher than that in the control group or the GP plus stellate ganglion (SG) ablation group (P<0.05). Spontaneous VF occurred in 8/12, 1/10 and 2/12 dogs in the GP ablation group, the GP plus SG ablation group and the control group, respectively (P<0.05). VFT in the GP ablation group showed a decreased trend though a significant difference was not achieved compared with the control or the GP plus SG ablation group.
    CONCLUSIONS: GP ablation increases the risk of ventricular arrhythmias in the AMI heart compared to the normal heart.
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