A multi-dosing regimen to enhance the spatial memory of normal rats with α5-containing GABAA receptor negative allosteric modulator L-655,708

RATIONALE AND OBJECTIVES

The reported inconsistent effects of negative allosteric modulators of α5-containing GABA_A receptors on learning and memory may be attributed to receptor selectivity, effective plasma concentration maintenance, and administration time. This study aimed to compare the effects of L-655,708 administered by single-dosing regimen versus multi-dosing regimen on spatial memory, signaling molecules, and brain functional connectivity.

METHODS

After comparing the maintenance time of the effective plasma concentration of L-655,708 between multi-dosing and single-dosing regimens, we further compared the effects of the administration of the two regimens at different phases (before-learning, during-learning, and before-probe) of the Morris water maze (MWM) test on the performance of learning and memory and the levels of signaling molecules related to learning and memory in hippocampal tissues. Functional connectivity analyses between hippocampal and cortical regions were performed to further clarify the effects of the multi-dosing regimen.

RESULTS

The multi-dosing regimen could maintain the effective plasma concentration of L-655,708 much longer than the single-dosing regimen. Only the multi-dosing regimen for L-655,708 administration during the learning period led to significant improvement in spatial memory in the MWM test and increases in levels of glutamate receptors and phosphorylated signaling molecules (p-PKAα, p-CaMKII, and p-CREB-1). Compared with the vehicle control, the multi-dosing regimen increased the functional connectivity of the left hippocampal CA1 with cingulate and motor cortices.

CONCLUSIONS

A multi-dosing regimen for L-655,708 administered during the learning period is an effective strategy to improve spatial memory, increase signaling molecule levels, and enhance the functional connectivity of the hippocampus.

Identification, antibacterial activities and action mode of two macins from manila clam Venerupis philippinarum

In this study, two macins were identified from clam Venerupis philippinarum (designated as VpMacin-1 and VpMacin-2). They showed 64.71% similarity with each other. The highest mRNA expression of VpMacin-1 and VpMacin-2 was detected in gills and hepatopancreas, respectively, in non-stimulated clams, and their expression could be induced significantly in hemocytes after Vibrio anguillarum infection. Silencing of VpMacin-1 and VpMacin-2 led to 22% and 49% mortality 6 days post infection. Escherichia coli cells were killed by recombinant protein rVpMacin-1 and rVpMacin-2 within 1000 and 400 min, respectively, at a concentration of 1.0 × MIC. Compared with rVpMacin-1, rVpMacin-2 not only showed higher broad-spectrum antimicrobial activities towards Vibrio strains, but possessed stronger abilities to inhibit the formation of bacterial biofilm. Both membrane integrity and electrochemical assay indicated that rVpMacins were capable of causing bacterial membrane permeabilization, especially for rVpMacin-2. Besides, rVpMacin-1 significantly induced both phagocytic (0.1 and 1.0 × MIC, p < 0.05) and chemotactic effects (0.1 × MIC, p < 0.01) of hemocytes, while there was no significant increase for rVpMacin-2. Overall, our results suggested that VpMacin-1 and VpMacin-2 play important roles in host defense against invasive pathogens.

The impact of investor attention during COVID-19 on investment in clean energy versus fossil fuel firms

The outbreak of the COVID-19 pandemic has had significant negative impacts on financial markets, including energy stock markets. However, recently proposed and implemented green recovery plans may mean that clean energy firms demonstrate better performance than fossil fuel firms after the pandemic. As more voices call for the update of clean energy, theory on investor attention suggests investors will pay more attention to the potential to invest in clean energy stocks. Using a sample period of eight weeks before and during the pandemic, we find that the negative impact of the outbreak on both clean energy and fossil fuel firms is more significant for fossil fuel firms. Our results further show that during the pandemic there have been improved returns for clean energy firms as a consequence of investor attention, but not for fossil fuel firms. Our findings provide empirical evidence for the advantages of green recovery schemes in influencing financial markets, especially for clean energy stocks. These results suggest there are benefits for further promotion and implementation of green recovery stimulus measures post-pandemic.

14-3-3ζ and 14-3-3ε are involved in innate immune responses in Pacific abalone (Haliotis discus hannai)

The 14-3-3 proteins play important roles in various cellular processes by binding to different ligands, but little is known about these proteins in mollusks. In this study, two 14-3-3 cDNAs were identified from the Pacific abalone Haliotis discus hannai (designated 14-3-3ζ and 14-3-3ε), possessing 59.40% identity with each other. Both genes were predominantly expressed in the gills of unchallenged abalones, and their mRNA signals could also be detected in several other tissues, including the mantle, hepatopancreas and ovary. However, after Vibrio harveyi challenge, hemocytes were induced significantly (p < 0.01). Meanwhile, phagocytosis was inhibited, but apoptosis, reactive oxygen species formation, and caspase 3 expression were significantly induced (p < 0.01), and they were all suppressed with 14-3-3ζ knockdown (p < 0.01). The differences were that silencing 14-3-3ε reverted the decline in the phagocytic rate derived from bacterial infection, while ROS formation was not influenced significantly. In addition, the expression levels of several antimicrobial peptide and proinflammatory cytokine genes were also decreased with the silencing of 14-3-3 genes. However, with the knockdown of 14-3-3ζ, the expression of 14-3-3ε was further significantly increased (p < 0.01), and vice versa. Overall, our results suggested that 14-3-3ζ and 14-3-3ε should play important roles in innate immunity against V. harveyi infection.

Scalable synthesis of 3D porous germanium encapsulated in nitrogen-doped carbon matrix as an ultra-long-cycle life anode for lithium-ion batteries

Germanium-based materials attract more interest as anodes for lithium-ion batteries, stemming from their physical and chemical advantages. However, these materials inevitably undergo capacity attenuation caused by significant volumetric variation in repeated electrochemical processes. Herein, we designed 3D porous Ge/N-doped carbon nanocomposites by the encapsulation of 3D porous Ge in a nitrogen-doped carbon matrix (denoted as 3D porous Ge/NC). The 3D porous structure can accommodate the volume change during alloying/dealloying processes and improve the penetration of the electrolyte. Furthermore, the doping of N in the carbon framework could introduce more defects and active sites, which can also contribute to electron transportation and lithium-ion diffusion. The half-cell test found that at a current density of 1 C (1 C = 1600 mA h g^-1), the specific capacity stabilized at 917.9 mA h g^-1 after 800 cycles; and the specific capacity remained at 542.4 mA h g^-1 at 10 C. When assembled into a 3D porous Ge/NC//LiFePO₄ full cell, the specific capacity was stabilized at 101.3 mA h g^-1 for 100 cycles at a current density of 1 C (1 C = 170 mA h g^-1), and the cycle specific capacity was maintained at 72.6 mA h g^-1 at a high current density of 5 C. This work develops a low-cost, scalable and simple strategy to improve the electrochemical performance of these alloying type anode materials with huge volume change in the energy storage area.

Identify differential genes and cell subclusters from time-series scRNA-seq data using scTITANS

Time-series single-cell RNA sequencing (scRNA-seq) provides a breakthrough in modern biology by enabling researchers to profile and study the dynamics of genes and cells based on samples obtained from multiple time points at an individual cell resolution. However, cell asynchrony and an additional dimension of multiple time points raises challenges in the effective use of time-series scRNA-seq data for identifying genes and cell subclusters that vary over time. However, no effective tools are available. Here, we propose scTITANS (https://github.com/ZJUFanLab/scTITANS), a method that takes full advantage of individual cells from all time points at the same time by correcting cell asynchrony using pseudotime from trajectory inference analysis. By introducing a time-dependent covariate based on time-series analysis method, scTITANS performed well in identifying differentially expressed genes and cell subclusters from time-series scRNA-seq data based on several example datasets. Compared to current attempts, scTITANS is more accurate, quantitative, and capable of dealing with heterogeneity among cells and making full use of the timing information hidden in biological processes. When extended to broader research areas, scTITANS will bring new breakthroughs in studies with time-series single cell RNA sequencing data.

Knockdown of ALDH1A3 reduces breast cancer stem cell marker CD44 via the miR-7-TGFBR2-Smad3-CD44 regulatory axis

Inhibition of aldehyde dehydrogenase 1 family member A3 (ALDH1A3) has been revealed to lead to significant increase of microRNA (miR)-7 expression and decrease of CD44 expression in breast cancer stem cells (BCSCs), however the mechanism is not clear. The aim of the present study was to investigate the regulatory relationship between ALDH1A3, miR-7, and CD44 in BCSCs. The expression of ALDH1A3 was inhibited by small interfering RNA (siRNA or si), and the expression of miR-7 was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Then, the ratio of CD44⁺ cells was analyzed by flow cytometry in MDA-MB-231 cells. The dual-luciferase reporter system was used to demonstrate that miR-7 binds to transforming growth factor-β receptor 2 (TGFBR2) 3'UTR, and ChIP-PCR determined whether the transcription factor Smad3 binds to the upstream regulatory region of the CD44 promoter. The results revealed that siALDH1A3 downregulated ALDH1A3 and promoted miR-7 expression, which resulted in downregulation of CD44 expression. siALDH1A3 also downregulated the CD44 expression on the surface of MDA-MB-231 cells and inhibited the G2/M phase in BCSCs as analyzed by flow cytometry. In addition, lenti-miR-7 cells transfected with TGF-β1 + SB431542 revealed that lenti-miR-7 inhibited the TGF-β1 pathway by inhibiting Smad2/3/4 expression and, thus, downregulated CD44 expression. miR-7 was revealed to directly bind to the TGFBR2 3'UTR through dual-luciferase reporter assay, and Smad3, a transcription factor, through ChIP-PCR was demonstrated to bind to the upstream region of the CD44 promoter. These results demonstrated the existence of the ALDH1A3-miR-7-TGFBR2-Smad3-CD44 axis in MDA-MB-231 cells. RT-qPCR results of 12 breast cancer surgical specimens and SK-BR-3, MCF-7, and LD cell lines further confirmed the presence of the regulatory axis. In conclusion the findings from the present study demonstrated that the ALDH1A3-miR-7-TGFBR2-Smad3-CD44 regulatory axis was highly efficient in the inhibition of CD44 expression in BCSCs, and that the regulatory expression of ALDH1A3 and miR-7 may provide a strategy in the therapy of breast cancer.

Unusual Exchange Couplings and Intermediate Temperature Weyl State in Co_{3}Sn_{2}S_{2}

Understanding magnetism and its possible correlations to topological properties has emerged to the forefront as a difficult topic in studying magnetic Weyl semimetals. Co_{3}Sn_{2}S_{2} is a newly discovered magnetic Weyl semimetal with a kagome lattice of cobalt ions and has triggered intense interest for rich fantastic phenomena. Here, we report the magnetic exchange couplings of Co_{3}Sn_{2}S_{2} using inelastic neutron scattering and two density functional theory (DFT) based methods: constrained magnetism and multiple-scattering Green's function methods. Co_{3}Sn_{2}S_{2} exhibits highly anisotropic magnon dispersions and linewidths below T_{C}, and paramagnetic excitations above T_{C}. The spin-wave spectra in the ferromagnetic ground state is well described by the dominant third-neighbor "across-hexagon" J_{d} model. Our density functional theory calculations reveal that both the symmetry-allowed 120° antiferromagnetic orders support Weyl points in the intermediate temperature region, with distinct numbers and the locations of Weyl points. Our study highlights the important role Co_{3}Sn_{2}S_{2} can play in advancing our understanding of kagome physics and exploring the interplay between magnetism and band topology.

Combating the Infodemic: A Chinese Infodemic Dataset for Misinformation Identification

Misinformation posted on social media during COVID-19 is one main example of infodemic data. This phenomenon was prominent in China when COVID-19 happened at the beginning. While a lot of data can be collected from various social media platforms, publicly available infodemic detection data remains rare and is not easy to construct manually. Therefore, instead of developing techniques for infodemic detection, this paper aims at constructing a Chinese infodemic dataset, "infodemic 2019", by collecting widely spread Chinese infodemic during the COVID-19 outbreak. Each record is labeled as true, false or questionable. After a four-time adjustment, the original imbalanced dataset is converted into a balanced dataset by exploring the properties of the collected records. The final labels achieve high intercoder reliability with healthcare workers' annotations and the high-frequency words show a strong relationship between the proposed dataset and pandemic diseases. Finally, numerical experiments are carried out with RNN, CNN and fastText. All of them achieve reasonable performance and present baselines for future works.

Revealing the Chemical Bonding in Adatom Arrays via Machine Learning of Hyperspectral Scanning Tunneling Spectroscopy Data

The adatom arrays on surfaces offer an ideal playground to explore the mechanisms of chemical bonding via changes in the local electronic tunneling spectra. While this information is readily available in hyperspectral scanning tunneling spectroscopy data, its analysis has been considerably impeded by a lack of suitable analytical tools. Here we develop a machine learning based workflow combining supervised feature identification in the spatial domain and unsupervised clustering in the energy domain to reveal the details of structure-dependent changes of the electronic structure in adatom arrays on the Co₃Sn₂S₂ cleaved surface. This approach, in combination with first-principles calculations, provides insight for using artificial neural networks to detect adatoms and classifies each based on their local neighborhood comprised of other adatoms. These structurally classified adatoms are further spectrally deconvolved. The unexpected inhomogeneity of electronic structures among adatoms in similar configurations is unveiled using this method, suggesting there is not a single atomic species of adatoms, but rather multiple types of adatoms on the Co₃Sn₂S₂ surface. This is further supported by a slight contrast difference in the images (or slight size variation) of the topography of the adatoms.

Quercetin protects oral mucosal keratinocytes against lipopolysaccharide-induced inflammatory toxicity by suppressing the AKT/AMPK/mTOR pathway

BACKGROUND

Cytokines can induce a chronic inflammatory response in the periodontium, leading to periodontitis. Quercetin, a naturally occuring flavonoid, has been shown to inhibit periodontitis, but how it works is poorly understood. In this study, we assessed the impact of quercetin on lipopolysaccharide (LPS)-induced inflammatory damage in oral mucosal keratinocytes (hOMK107) and explored its underlying mechanism.

METHODS

The viability and apoptosis of hOMK107 cells were measured after exposure to LPS, followed or not by quercetin. The production of IL-1β, IL-6, IL-8, TNF-ɑ, iNOS, and COX-2 was quantified by enzyme-linked immunosorbent assay (ELISA), while levels of Akt, AMPK, and mTOR and their phosphorylation were detected semi-quantitatively by western blotting.

RESULTS

Quercetin significantly improved cell viability and apoptosis by reversing LPS-induced upregulation of Bax and downregulation of Bcl-2 in hOMK107 cells. Quercetin decreased the production of IL-1β, IL-6, IL-8, TNF-ɑ, iNOS, and COX-2, as well as signal transduction via the Akt/AMPK/mTOR pathway. Inhibitors of Akt, AMPK, and mTOR strengthened the anti-apoptotic effects of quercetin, while agonists of Akt, AMPK, or mTOR or Akt overexpression weakened the anti-apoptotic effects.

CONCLUSION

These results indicate that quercetin may have a potential protective effect against the chronic inflammation-related periodontitis via suppressing Akt/AMPK/mTOR pathway.

Application of painless nursing in cesarean delivery parturients due to the failure of natural childbirth via labor analgesia

OBJECTIVE

To evaluate the application of painless nursing in cesarean delivery parturients due to the failure of natural childbirth via labor analgesia.

METHODS

A total of 124 parturients who were transferred to cesarean delivery due to the failure of natural childbirth via labor analgesia were selected and randomly divided into two groups. The control group received routine nursing, while the research group was given painless nursing in the operating room, which mainly included interventions in terms of the environment, labor process, and delivery procedure. The visual analog scale (VAS), gestation outcome, stress response, anxiety, sleep quality, and nursing satisfaction were compared between the two groups.

RESULTS

Compared with the control group, the sleep quality score was significantly lower in the research group (all P<0.001). Compared with before nursing, the anxiety and VAS scores of the two groups were significantly decreased after nursing (P<0.001). Additionally, the anxiety and VAS scores of the research group after nursing were significantly lower than those of the control group (P<0.001). There was no significant difference for the gestation outcome between the two groups (P>0.05). Compared with before nursing, the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) after nursing were significantly downregulated, while the level of superoxide dismutase (SOD) was significantly upregulated in both groups (all P<0.001). Compared with the control group, the levels of MDA and ROS were significantly lower, while SOD level was significantly higher in the research group after nursing (all P<0.001). Compared with the control group, the nursing satisfaction was significantly higher in the research group (P<0.05).

CONCLUSION

The painless nursing for cesarean delivery parturients in the operating room due to the failure of natural childbirth via labor analgesia can effectively improve the sleep quality and negative moods of the parturients, reduce the degree of pain and stress response in the process of delivery, and result in better satisfaction and compliance.

Small universal mechanical module driven by a liquid metal droplet

Gallium-based liquid metal droplets (LMDs) from micro-electromechanical systems (MEMS) have gained much attention due to their precise and sensitive controllability under an electric field. Considerable research progress has been made in the field of actuators by taking advantage of the continuous electrowetting (CEW) present within the solution. However, the motion generated is confined within the specific liquid environment and is lacking a way to transmit its motion outwardly, which undoubtedly serves as the greatest obstacle restricting any further development. Therefore, a driving module is proposed to generate rotational motion outside the solution for universality. Its performance can be easily tuned by adjusting the applied voltage. As an example of further application, the module is designed in the form of a pump that realizes the continuous/intermittent propulsion to mimic the veins/arteries of the human body without the problem in the previous LMD-based pumps. The feasibility of this pump in the on-chip in vitro analysis is proved by preparing a dynamic cell culture to simulate the movement of biofluids within human bodies. This study proposes an optional solution with an LMD-based motor for generating rotational motion and to expand current research on soft materials in actuators.

Bayesian Learning of Adatom Interactions from Atomically Resolved Imaging Data

Atomic structures and adatom geometries of surfaces encode information about the thermodynamics and kinetics of the processes that lead to their formation, and which can be captured by a generative physical model. Here we develop a workflow based on a machine-learning-based analysis of scanning tunneling microscopy images to reconstruct the atomic and adatom positions, and a Bayesian optimization procedure to minimize statistical distance between the chosen physical models and experimental observations. We optimize the parameters of a 2- and 3-parameter Ising model describing surface ordering and use the derived generative model to make predictions across the parameter space. For concentration dependence, we compare the predicted morphologies at different adatom concentrations with the dissimilar regions on the sample surfaces that serendipitously had different adatom concentrations. The proposed workflow can be used to reconstruct the thermodynamic models and associated uncertainties from the experimental observations of materials microstructures. The code used in the manuscript is available at https://github.com/saimani5/Adatom_interactions.

Comparison of Posterior Unilateral Vertebral Column Resection Versus Posterior Vertebral Column Resection for Severe Thoracolumbar Angular Kyphosis as a Revision Surgical Modality: A Retrospective Cohort Study

OBJECTIVE

The objective of this study was to determine the safety and efficacy of posterior unilateral vertebral column resection (PUVCR) as revision surgery for severe thoracolumbar angular kyphosis.

PATIENTS AND METHODS

This is a retrospective cohort study. Adult patients undergoing revision surgery for severe thoracolumbar angular kyphosis in 2010-2016 with ≥2-year follow-up at our institution were assessed. Perioperative complications and clinical outcomes, including blood loss, operation time, Visual Analog Scale score, Oswestry Disability Index, and preoperative and postoperative kyphotic angles, were analyzed.

RESULTS

This study included 58 patients who were divided into the PUVCR group and the posterior vertebral column resection (PVCR) group. Age ( P =0.810), sex distribution ( P =0.500), and vertebrae that underwent surgery ( P =0.638) were similar in the 2 groups. Shorter mean operation time was observed in the PUVCR group as compared with the PVCR group ( P <0.001). In addition, less blood loss was recorded in the PUVCR group as compared with the PVCR group ( P =0.001). There were no significant differences between the 2 groups in a change of Visual Analog Scale scores postoperation versus preoperation ( P =0.961), and at postoperative 3 months ( P =0.906), 12 months ( P =0.752), and 24 months ( P =0.811) versus postoperation, respectively. There were no significant differences between the 2 groups in Oswestry Disability Index changes postoperation versus preoperation ( P =0.157), and at postoperative 3 months ( P =0.899), 12 months ( P =0.947), and 24 months ( P =0.811) versus postoperation, respectively. PUVCR and PVCR were comparable in deformity correction ( P =0.434) and final angle correction ( P =0.790). Complication rates in the PUVCR and PVCR groups were 7.1% and 36.7%, respectively.

CONCLUSION

PUVCR has comparable safety and efficacy to PVCR in treating severe thoracolumbar angular kyphosis, with the advantages of the shorter operation time, less blood loss, and fewer complications.

Adalimumab ameliorates memory impairments and neuroinflammation in chronic cerebral hypoperfusion rats

Vascular dementia (VaD) is the second most common type of dementia worldwide. Although there are five FDA-approved drugs for the treatment of Alzheimer's disease (AD), none of them have been applied to treat VaD. Adalimumab is a TNF-α inhibitor that is used for the treatment of autoimmune diseases such as rheumatoid arthritis. In a recent retrospective case-control study, the application of adalimumab for rheumatoid or psoriasis was shown to decrease the risk of AD. However, whether adalimumab can be used for the treatment of VaD is not clear. In this study, we used 2VO surgery to generate a VaD rat model and treated the rats with adalimumab or vehicle. We demonstrated that VaD rats treated with adalimumab exhibited significant improvements in memory. In addition, adalimumab treatment significantly alleviated neuronal loss in the hippocampi of VaD rats. Moreover, adalimumab significantly reduced microglial activation and reversed M1/M2 polarization in VaD rats. Furthermore, adalimumab treatment suppressed the activity of NF-κB, an important neuroinflammatory transcription factor. Finally, adalimumab displayed a protective role against oxidative stress in VaD rats. Our results indicate that adalimumab may be applied for the treatment of human patients with VaD.

Cross-Layer-Aided Opportunistic Routing for Sparse Underwater Wireless Sensor Networks

Underwater wireless sensor networks (UWSNs) have emerged as a promising technology to monitor and explore the oceans instead of traditional undersea wireline instruments. Traditional routing protocols are inefficient for UWSNs due to the specific nature of the underwater environment. In contrast, Opportunistic Routing (OR) protocols establish an online route for each transmission, which can well adapt with time-varying underwater channel. Cross-layer design is an effective approach to combine the metrics from different layers to optimize an OR routing in UWSNs. However, typical cross-layer OR routing protocols that are designed for UWSNs suffer from congestion problem at high traffic loads. In this paper, a Cross-Layer-Aided Opportunistic Routing Protocol (CLOR) is proposed to reduce the congestion in multi-hop sparse UWSNs. The CLOR consists of a negotiation phase and transmission phase. In the negotiation phase, the cross-layer information in fuzzy logic is utilized to attain an optimal forwarder node. In the transmission phase, to improve the transmission performance, a burst transmission strategy with network coding is exploited. Finally, we perform simulations of the proposed CLOR protocol in a specific sea region. Simulation results show that CLOR significantly improves the network performances at various traffic rates compared to existing protocols.

Quality improvement of nursing on patients with complex cerebral arteriovenous malformation undergoing hybrid surgery: a prospective single-center study

Background

We sought to explore an optimal clinical nursing mode following a hybrid surgery for cerebral arteriovenous malformation.

Methods

Patients with complex cerebral arteriovenous malformations seen in our neurosurgery department from January 2016 to December 2017 were prospectively enrolled. The hybrid surgery protocol included “angiographic diagnosis, surgical resection, and intraoperative angiographic evaluation” and “angiographic diagnosis and embolization, surgical resection, and intraoperative angiographic evaluation”. The patients were randomly stratified into intensive care group and routine care group. After surgery, intensive or routine care was provided, and the prognosis of patients was evaluated, with a subsequent comparative analysis.

Results

A total of 109 cases were divided into the routine nursing group (n = 54 cases) and intensive nursing group (n = 55 cases). There were no significant differences between the two groups in baseline data before surgery. Postoperative lung infection in the intensive nursing group was significantly less frequent than those in the routine nursing group (5.5% vs. 18.5%, P=0.039) with pulmonary infection and lower extremity venous thrombosis (5.5% vs. 24.1%, P=0.006). The average hospital stay in the intensive nursing group was 14.4 ± 5.78 days, which was significantly lower than that in the routine nursing group (19.3 ± 6.38 days, P=0.013). At 3 months’ follow-up after surgery, the Generic Quality of Life Inventory-74 (GQOLI-74) dimension score and GQOLI-74 total score in the enhanced group were significantly better than those in the routine nursing group (P=0.017 and 0.023, respectively).

Conclusions

Intensive postoperative nursing can improve the safety of patients after hybrid surgery, reduce the postoperative complications and the average length of hospital stay, and improve the quality of life of patients.

Toward a High-Performance Aqueous Zinc Ion Battery: Potassium Vanadate Nanobelts and Carbon Enhanced Zinc Foil

Aqueous rechargeable zinc ion batteries are promising candidates for grid-scale applications owing to their low cost and high safety. However, they are plagued by the lack of suitable cathode and anode materials. Herein, we report on potassium vanadate (KVO) nanobelts as a promising cathode for an aqueous zinc ion battery, which shows a high discharge capacity of 461 mA h g^-1 at 0.2 A g^-1 and exhibits a capacity retention of 96.2% over 4000 cycles at 10 A g^-1. Furthermore, to enhance the energy efficiency in an aqueous zinc ion battery, a facile and effective method on the anode is demonstrated. The energy efficiency increases from 47.5% for Zn//KVO coupled with the zinc foil anode to 66.5% for AB-Zn//KVO coupled with an acetylene black film improved zinc foil anode at 10 A g^-1. The remarkable electrochemical performance makes AB-Zn//KVO a strong candidate for a high-performance aqueous zinc ion battery.

Continuous-Flow Nanoparticle Trapping Driven by Hybrid Electrokinetics in Microfluidics

We introduce herein an efficient microfluidic approach for continuous transport and localized collection of nanoparticles via hybrid electrokinetics, which delicately combines linear and nonlinear electrokinetics driven by a composite DC-biased AC voltage signal. The proposed technique utilizes a simple geometrical structure, in which one or a series of metal strips serving as floating electrode (FE) are attached to the substrate surface and arranged in parallel between a pair of coplanar driving electrodes (DE) in a straight microchannel. On application of a DC-biased AC electric field across the channel, nanoparticles can be transported continuously by DC bulk electroosmotic flow, and then trapped selectively onto the metal strips due to AC-field induced-charge electrokinetic (ICEK) phenomenon, which behaves as counter-rotating micro-vortices around the ideally polarizable surfaces of FE. Finite-element simulation is carried out by coupling the dual-frequency electric field, flow field and sample mass transfer in sequence, for guiding a practical design of the microfluidic nanoparticle concentrator. With the optimal device geometry, the actual performance of the technique is investigated with respect to DC bias, AC voltage amplitude, and field frequency by using both latex nanospheres (∼500 nm) and BSA molecules (∼10 nm). Our experimental observation indicates nanoparticles are always enriched into a narrow bright band on the surface of each FE, and a horizontal concentration gradient even emerges in the presence of multiple metal strips, which therefore permits localized analyte enrichment. The proposed trapping method is supposed to guide an elaborate design of flexible electrokinetic frameworks embedding FE for continuous-flow analyte manipulation in modern microfluidic systems.