bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of calcination atmosphere on the performance of the co‐precipitated Ni/ZrO2 catalyst in dry reforming of methane
Authors: Zhang Meng , Zhang Junfeng , Zhou Zeling , Zhang Qingde , Tan Yisheng , Han Yizhuo 
Published: April 2021

AbstractThe effects of the calcination atmospheres (H2, N2, and O2) on the performance of Ni/ZrO2 catalysts prepared by the conventional co‐precipitation method for dry reforming of methane (DRM) were investigated in this work. The catalyst calcined in O2 atmosphere (NZO) showed the highest Ni dispersion (10.99%), followed by the one calcined in N2 (NZN, 8.14%) and H2 atmosphere (NZH, 5.97%). Additionally, NZO and NZN exhibited relatively stronger metal‐support interaction than NZH and the incorporated Ni species on NZO and NZN were capable of stabilizing the metastable tetragonal ZrO2, which possessed more oxygen vacancies and higher oxygen mobility than monoclinic ZrO2. The evaluation results revealed that the activity of the employed catalysts displayed the following sequence: NZO > NZN > NZH, which was mainly determined by their Ni dispersion. The amount of carbon deposited on NZO (2.2%) was less than that on NZN (5.0%), and the deactivation rate of NZO (0.47% per hour) was slower than that of NZN (0.53% per hour). Due to its low CH4 conversion and the weak metal‐support interaction, NZH showed the least carbon deposition (1.1%) and the slowest deactivation rate (0.37% per hour) among the representative catalysts.
Synthesis of Phenanthridine and Quinoxaline Derivatives viaCopper‐Catalyzed Radical Cyanoalkylation of Cyclobutanone Oxime Esters and Vinyl Azides
Authors: Liang Qi , Lin Long , Li Guodong , Kong Xianqiang , Xu Bo 
Published: April 2021

Main observation and conclusionA copper‐catalyzed radical cyclization of cyclobutanone oxime esters and vinyl azide is described. This method provides facile access to cyanoalkyl‐substituted phenanthridines and quinoxalines with excellent isolated yields. Moreover, these reactions proceed under mild conditions with a board substrate scope and excellent functional group tolerance.
A Jackknife empirical likelihood approach forK‐sample Tests
Authors: Sang Yongli , Dang Xin , Zhao Yichuan 
Published: April 2021

AbstractThe categorical Gini correlation is an alternative measure of dependence between categorical and numerical variables, which characterizes the independence of the variables. A non‐parametric test based on the categorical Gini correlation for the equality ofKdistributions is developed. By applying the jackknife empirical likelihood approach, the standard limiting chi‐squared distribution with degrees of freedom ofK − 1 is established and is used to determine the critical value andp‐value of the test. Simulation studies show that the proposed method is competitive with existing methods in terms of power of the tests in most cases. The proposed method is illustrated in an application on a real dataset.
Assessment of non‐vitamin K antagonist oral anticoagulants for the management of left ventricular thrombus
Authors: Li Shunhui , Deng Yuqing , Tong Yifan , Xiong Qiangzhen , Hu Jing , Jiang Xiaojie , He Tao , Liu Liyun , Chen Hui 
Published: April 2021

AbstractAlthough several studies have assessed the effect of non‐vitamin K antagonist oral anticoagulants (NOACs) relative to that of vitamin K antagonists (VKAs) in patients with left ventricular thrombus, the results remain controversial. Herein, a meta‐analysis was performed to compare the effectiveness and safety of NOACs versus VKAs for the treatment of left ventricular thrombus. We systematically searched the Cochrane Library, PubMed and Embase databases until November 2020 for studies that compared the effects of NOACs versus VKAs in patients with left ventricular thrombus. The treatment effects were expressed as odds ratios (ORs) with 95% confidence intervals (CIs) and pooled by a random‐effects model. Seven retrospective studies involving 865 patients with left ventricular thrombus (266 NOAC and 599 VKA users) were included. The pooled analysis suggested no difference in the rate of thrombus resolution between the NOAC and VKA groups (OR = 0.83, 95% CI 0.61–1.13). There were also no differences in the rates of stroke or systemic embolism (OR = 0.62, 95% CI 0.20–1.97), bleeding events (OR = 0.73, 95% CI 0.37–1.45), or all‐cause death (OR = 0.92, 95% CI 0.50–1.69) between patients treated with NOACs and those treated with VKAs. In addition, the rates of thrombus resolution, stroke or systemic embolism, bleeding events, and all‐cause death between NOAC‐ and warfarin‐treated patients were also similar. Our current evidence suggested that NOAC and VKA users had similar rates of thrombus resolution and clinical outcomes among patients with left ventricular thrombus. Further large‐scale prospective studies should confirm our results.
CX3CR1 mutation alters synaptic and astrocytic protein expression, topographic gradients, and response latencies in the auditory brainstem
Authors: Milinkeviciute Giedre , Chokr Sima M. , Castro Emily M. , Cramer Karina S. 
Published: April 2021

AbstractThe precise and specialized circuitry in the auditory brainstem develops through adaptations of cellular and molecular signaling. We previously showed that elimination of microglia during development impairs synaptic pruning that leads to maturation of the calyx of Held, a large encapsulating synapse that terminates on neurons of the medial nucleus of the trapezoid body (MNTB). Microglia depletion also led to a decrease in glial fibrillary acidic protein (GFAP), a marker for mature astrocytes. Here, we investigated the role of signaling through the fractalkine receptor (CX3CR1), which is expressed by microglia and mediates communication with neurons. CX3CR1−/− and wild‐type mice were studied before and after hearing onset and at 9 weeks of age. Levels of GFAP were significantly increased in the MNTB in mutants at 9 weeks. Pruning was unaffected at the calyx of Held, but we found an increase in expression of glycinergic synaptic marker in mutant mice at P14, suggesting an effect on maturation of inhibitory inputs. We observed disrupted tonotopic gradients of neuron and calyx size in MNTB in mutant mice. Auditory brainstem recording (ABR) revealed that CX3CR1−/− mice had normal thresholds and amplitudes but decreased latencies and interpeak latencies, particularly for the highest frequencies. These results demonstrate that disruption of fractalkine signaling has a significant effect on auditory brainstem development. Our findings highlight the importance of neuron–microglia–astrocyte communication in pruning of inhibitory synapses and establishment of tonotopic gradients early in postnatal development.
Nano‐Optical Tweezers: Methods and Applications for Trapping Single Molecules and Nanoparticles
Authors: Kolbow Joshua D. , Lindquist Nathan C. , Ertsgaard Christopher T. , Yoo Daehan , Oh Sang‐Hyun 
Published: April 2021

AbstractOptical tweezers were developed in 1970 by Arthur Ashkin as a tool for the manipulation of micron‐sized particles. Ashkin's original design was then adapted for a variety of purposes, such as trapping and manipulation of biological materials[1] and the laser cooling of atoms.[2,3] More recent development has led to nano‐optical tweezers, for trapping particles on the scale of only a few nanometers, and holographic tweezers, which allow for dynamic control of multiple traps in real‐time. These alternatives to conventional optical tweezers have made it possible to trap single molecules and to perform a variety of studies on them. Presented here is a review of recent developments in nano‐optical tweezers and their current and future applications.
Double‐gate line‐tunneling field‐effect transistor devices for superior analog performance
Authors: Simhadri Hariprasad , Dan Surya Shankar , Yadav Ramakant , Mishra Ashutosh 
Published: April 2021

SummaryThis paper presents a double‐gate line‐tunneling field‐effect transistor (DGLTFET) device optimized for superior analog performance. DGLTFET has thrice the on currents Ion, at least one order lower off currents I o f f, twice the transconductance gm, at least two orders higher output resistance ro, and at least two orders higher overall intrinsic gain gmro than the equivalent metal‐oxide‐semiconductor field‐effect transistor (MOSFET) having the same width at the same technology node. The proposed device, being a double‐gate (DG) structure, exhibits extremely high vertical fields which ensures that line‐tunneling dominates over the point‐tunneling by several orders. This eliminates the notorious “hump” or the “kink” effects observed in conventional LTFET characteristics, which are detrimental for analog applications. In this work, we have optimized the DGLTFET device by changing critical parameters like the epi‐layer thickness and its doping concentration, which have serious influence on the line‐tunneling behavior. Optimization of the critical parameters for enhanced line‐tunneling leads to improved analog performance parameters like gm and ro, and finally, superior analog circuits. The performance of the DGLTFET was benchmarked with the equivalent MOSFET in fundamental analog VLSI circuits, namely, CS amplifier (both resistive and cascode loads), current mirror (both single‐stage and cascode configurations), and a two‐stage op‐amp. This paper shows that the DGLTFET CS amplifier has a gain‐BW product or unity‐gain BW fT of 15 GHz, while that of MOSFET CS amplifier with the same bias current is 10 GHz. The DGLTFET current mirror has at least three orders of magnitude higher ro than the corresponding MOSFET current mirror. Similarly, the common‐mode rejection ratio (CMRR) of the DGLTFET op‐amp is 57 dB compared to the CMRR of 33.5 dB of the equivalent design in standard 45‐nm complementary metal‐oxide semiconductor (CMOS) technology. The 45‐nm library is the lowest industry‐standard technology node currently available free for academic licenses in the public domain; hence, the benchmarking for validation was carried out at 45 nm. However, the claims/investigations made in this work are also valid for lower technologies, and related results are excluded in this report keeping the manuscript length in mind.
Structural Variety of Iron Carbonyl Clusters Featuring Ferrocenylphosphines
Authors: Korb Marcus , Liu Xianming , Walz Sebastian , Mahrholdt Julia , Popov Alexey A. , Lang Heinrich 
Published: April 2021

AbstractThe reaction chemistry of Fe2(CO)9 (10) with ferrocenenyl dichlorophosphines of different substitution is discussed. Single FcPCl2, (5) as well as 1,1’‐ (6) and 1,2‐ (9) difunctionalized phosphines were used, of which 6 and 9, were prepared in a novel straightforward synthetic process. Substrate 5 gave butterfly‐shaped Fe2(CO)6(μ2‐Cl)(μ2‐PFcCl) and Fe2(CO)6(μ2‐PFcR1)(μ2‐PFcR2) (R1, R2=Cl, H). In addition, nido‐Fe3(CO)10(μ3‐PFc) and nido‐Fe3(CO)9(μ3‐PFc)2 were obtained. 1,1’‐Functionalized 6 bridges both ends of the Fe2(CO)6 entity. Therein, the so far smallest non‐binding P⋅⋅⋅P distance (2.7674(12) Å) between both 1,1’‐substituents is observed. Additionally, an ‘organometallic octabisvalene’, containing two [2]ferrocenophane entities was obtained. The eight‐membered cyclic structure is twisted by 35.31(9)° regarding their ferrocenyl axis. Usage of 1,2‐(PCl2)2 functionalized 9 produced two isomers of a P−P connected dimer, which coordinates towards two independent Fe2(CO)6 fragments in a novel μ,μ’,κ8 or bis(μ,κ4) fashion, resulting in a meso isomer with a planar core, and a racem mixture, possessing a pocket‐type structure. The latter shows the so far shortest observed P⋅⋅⋅P distance of 2.950(7) Å between two ortho P atoms of a ferrocenyl backbone. The results confirm that the geometric properties of ferrocenyls featuring 1,1’‐ and 1,2‐substitution patterns are not comparable with phenyl‐based analogues. X‐ray single crystal solid state structures, and DFT calculations were carried out.
Direct internal methane reforming in biogas fuelled solid oxide fuel cell; the influence of operating parameters
Authors: Saadabadi S. Ali , Illathukandy Biju , Aravind Purushothaman Vellayani 
Published: April 2021

AbstractInternal dry reforming (IDR) of methane for biogas‐fed solid oxide fuel cell (SOFC) applications has been experimentally investigated on planar Ni‐GDC (cermet anode) electrolyte‐supported cells. This study focuses on the effect of CO2 concentration, current density, operating temperature, and residence time on internal methane dry reforming. A single cell is fed with different CH4/CO2 mixture ratios between 0.6 and 1.5. Extra CO2 recovered from carbon capture plants can be utilized here as a reforming agent. The I‐V characterization curves are recorded at different operating conditions in order to determine the best electrochemical performance while the power production is maximized, and carbon deposition is suppressed. The outlet gas from the anode is analyzed by a micro gas chromatograph to investigate methane conversion inside the anode fuel channel and to understand its influence on the cell performance. Relatively long‐term experiments have been performed for all gas mixtures at 850°C under a current density of 2000 A m−2. The results indicate that when the cell is fed with biogas with an equimolar amount of CH4 and CO2, carbon deposition is prevented, and maximum power density is obtained.
Systematic review of the current psychosocial interventions for people with moderate to severe dementia
Authors: Hui Esther K. , Tischler Victoria , Wong Gloria H. Y. , Lau W. Y. Tiffany , Spector Aimee 
Published: April 2021

AbstractObjectiveDementia, a global epidemic, currently affects 50 million individuals worldwide. There are currently limited effective treatments for moderate to severe dementia, and most treatments focus on reducing symptoms rather than improving positive factors. It is unclear if improvements are not possible due to disease severity. This review examines the efficacy of the current psychosocial interventions for people with moderate to severe dementia, focusing on improving cognition and quality of life (QoL) to evaluate what treatments are working and whether improvements are possible.MethodsA systematic search was conducted using six key databases to identify psychosocial interventions for people with moderate to severe dementia, measuring cognition or QoL in randomized controlled trials (RCTs), published between 2000 and 2020.ResultsThe search identified 4193 studies, and 74 articles were assessed for full‐text review. Fourteen RCTs were included and appraised with the Physiotherapy Evidence Database Scale. The included RCTs were moderate in quality.ConclusionsAromatherapy and reminiscence therapy showed the strongest evidence in improving QoL. There was some evidence that aerobic exercise enhanced cognition, and a multicomponent study improved QoL. However, a quality assessment, using pre‐specified criteria, indicated many methodological weaknesses. While we found improvements in cognition and QoL for moderate to severe dementia, results must be interpreted with caution. Future interventions with rigorous study designs are a pressing need and required before we can recommend specific interventions.
Distinct and temporally associated neural mechanisms underlying concurrent, postsuccess, and posterror cognitive controls: Evidence from a stop‐signal task
Authors: Cao Hengyi , Cannon Tyrone D. 
Published: April 2021

AbstractCognitive control is built upon the interactions of multiple brain regions. It is currently unclear whether the involved regions are temporally separable in relation to different cognitive processes and how these regions are temporally associated in relation to different task performances. Here, using stop‐signal task data acquired from 119 healthy participants, we showed that concurrent and poststop cognitive controls were associated with temporally distinct but interrelated neural mechanisms. Specifically, concurrent cognitive control activated regions in the cingulo‐opercular network (including the dorsal anterior cingulate cortex [dACC], insula, and thalamus), together with superior temporal gyrus, secondary motor areas, and visual cortex; while regions in the fronto‐parietal network (including the lateral prefrontal cortex [lPFC] and inferior parietal lobule) and cerebellum were only activated during poststop cognitive control. The associations of activities between concurrent and poststop regions were dependent on task performance, with the most notable difference in the cerebellum. Importantly, while concurrent and poststop signals were significantly correlated during successful cognitive control, concurrent activations during erroneous trials were only correlated with posterror activations in the fronto‐parietal network but not cerebellum. Instead, the cerebellar activation during posterror cognitive control was likely to be driven secondarily by posterror activation in the lPFC. Further, a dynamic causal modeling analysis demonstrated that postsuccess cognitive control was associated with inhibitory connectivity from the lPFC to cerebellum, while excitatory connectivity from the lPFC to cerebellum was present during posterror cognitive control. Overall, these findings suggest dissociable but temporally related neural mechanisms underlying concurrent, postsuccess, and posterror cognitive control processes in healthy individuals.
Prognostic imaging variables for recurrent laryngeal and hypopharyngeal carcinoma treated with primary chemoradiotherapy: A systematic review and meta‐analysis
Authors: Smits Hilde J. G. , Assili Sanam , Kauw Frans , Philippens Marielle E. P. , de Bree Remco , Dankbaar Jan W. 
Published: April 2021

AbstractBackgroundIn this systematic review, we aim to identify prognostic imaging variables of recurrent laryngeal or hypopharyngeal carcinoma after chemoradiotherapy.MethodsA systematic search was performed in PubMed and EMBASE (1990–2020). The crude data and effect estimates were extracted for each imaging variable. The level of evidence of each variable was assessed and pooled risk ratios (RRs) were calculated.ResultsTwenty‐two articles were included in this review, 17 on computed tomography (CT) and 5 on magnetic resonance imaging (MRI) variables. We found strong evidence for the prognostic value of tumor volume at various cut‐off points (pooled RRs ranging from 2.09 to 3.03). Anterior commissure involvement (pooled RR 2.19), posterior commissure involvement (pooled RR 2.44), subglottic extension (pooled RR 2.25), and arytenoid cartilage extension (pooled RR 2.10) were also strong prognostic factors.ConclusionPretreatment tumor volume and involvement of several subsites are prognostic factors for recurrent laryngeal or hypopharyngeal carcinoma after chemoradiotherapy.
High performance nonvolatile organic field‐effect transistor memory devices based on pyrene diimide derivative
Authors: Wang Wei Vanessa , Zhang Yamin , Li Xiang‐Yang , Chen Zi‐Zhen , Wu Ze‐Hua , Zhang Lei , Lin Ze‐Wei , Zhang Hao‐Li 
Published: April 2021

AbstractDeveloping high‐quality electret layer is important for the fabrication of high‐performance nonvolatile organic field effect transistor memory devices (OFET‐NVMs). In this work, three representative aromatic diimide frameworks are employed for comparative studies as n‐type doping materials for the electret layers in OFET‐NVMs, which are naphthalene diimide (NDI), perylene diimide (PDI), and pyrene diimide (PyDI). When blended with polystyrene (PS) to prepare the electret layers, all the memory devices containing aromatic diimide dopants exhibited significantly improved performances compared with the undoped counterparts, indicating that low‐lying LUMO energy levels of these dopants are beneficial for charge injection. All the devices with n‐type dopants exhibited long retention times (more than 104 s) and good switching reliability in more than 400 continuous write‐read‐erase‐read cycles. Among them, the PyDI‐based memory device exhibited superior performance compared with other aromatic diimides, which achieved a memory window of 34.0 V, a trapping charge density of 1.98 × 1012 cm−2 along with an on/off ratio higher than 104. This work indicates that PyDI framework could be a new platform for the future design of n‐type dopant for high‐performance nonvolatile organic field‐effect transistor memory devices.image
A review of specialty fiber biosensors based on interferometer configuration
Authors: Li Xuegang , Chen Ning , Zhou Xue , Gong Pengqi , Wang Shankun , Zhang Yanan , Zhao Yong 
Published: April 2021

AbstractOptical fiber biosensors have attracted extensive research attention in fields such as public health research, environmental science, bioengineering, disease diagnosis and drug research. Accurate detection of biomolecules is essential to limit the extent of disease outbreaks and provide valuable guidance for regulatory agencies to take timely measures. Among many optical fiber sensors, optical fiber biosensors based on specialty fibers have the advantages of biocompatibility, small size, high measurement resolution, high stability and immunity to electromagnetic interference. In this paper, four types interferometer biosensors based on specialty fiber, namely Mach‐Zehnder interferometer, Michelson interferometer, Fabry ‐ Perot interferometer and Sagnac interferometer, are reviewed in terms of operating principles, sensing structure and application fields. The fiber types are further divided into micro‐nano optical fiber, thin core fiber, polarization maintaining fiber, polymer fiber, microstructure optical fiber. Furthermore, this paper evaluates the advantages and disadvantages of these interferometer biosensors. Finally, main challenging problems and expectational development direction of specialty fiber interferometer biosensors are summarized. This text clearly shows the huge development potential of optical fiber biosensors in biomedical.
Incorporating a structural extracellular matrix gradient into a porcine urinary bladder matrix‐based hydrogel dermal scaffold
Authors: Allbritton‐King Jules D. , Kimicata Megan , Fisher John P. 
Published: April 2021

AbstractThe increasing prevalence of chronic, nonhealing wounds necessitates the investigation of full‐thickness skin substitutes conducive to host integration and wound closure. Extracellular matrix (ECM)‐based hydrogel scaffolds mimic the physiological matrix environment of dermal cells, thereby conferring favorable cellular adhesion, infiltration, and proliferation. However, low‐concentration ECM hydrogels rapidly lose mechanical strength as they degrade, leaving them susceptible to shrinkage from fibroblast‐mediated contraction. Conversely, high‐concentration ECM hydrogels are typically too dense to permit nutrient diffusion and cellular migration. This study investigates the design and fabrication of a graded‐concentration hydrogel composed of porcine urinary bladder matrix (UBM) as a dermal scaffold for potential use in chronic wound treatment. Our method of UBM isolation and decellularization effectively removed native DNA while preserving matrix proteins. Hydrogels composed of a range of decellularized UBM (dUBM) concentrations were characterized and used to design a three‐tiered gradient hydrogel that promoted cellular activity and maintained structural integrity. The gradient dUBM hydrogel showed stability of cross‐sectional area during collagenase degradation, despite considerable loss of mass. The gradient dUBM hydrogel also resisted fibroblast‐mediated contraction while supporting high surface cell viability, demonstrating the mechanical support provided by denser layers of dUBM. Overall, incorporation of an ECM concentration gradient into a porcine UBM‐based hydrogel scaffold capitalizes on the unique advantages of both high and low‐concentration ECM hydrogels, and mitigates the structural weaknesses that have limited the efficacy of hydrogel dermal scaffolds for chronic wounds. Our gradient design shows promise for future development of stable, pro‐regenerative wound scaffolds with customized architectures using 3D printing.