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Lithium-tellurium (Li-Te) batteries have attracted increasing attention as a next-generation energy storage system due to the appealing electrical conductivity and volumetric capacity. Porous carbon hosts are widely used for Te confinement to achieve good electrochemical performance in Li–Te batteries. However, there is a lack of understanding of the effect of carbon pore structure on the performance of Te/C cathodes. Herein, two types of carbons, one with micropores (ASAC25) and the other with mixed micropores and mesopores (ASAC30) are selected as Te hosts to clarify the role of carbon pore structure. Detailed investigations reveal that micropores, rather than mesopores, are critical for effective Te confinement due to complete infiltration of Te in micropores and enhanced Te and C interaction, thus enabling superior stability in ASAC25-Te. The dramatic capacity decline of ASAC30-Te is caused by the dissolution of bulky Te and the loss of active materials in long cycles. ASAC25-Te also achieved exceptional capacity retention of 83.3% after 500 cycles at 1C. Moreover, this work found that the ASAC25 carbon host should be partially filled with Te up to ∼60 wt% to accommodate volume change of Te. The clarification is expected to provide guidance on the further development of high-energy-density Te-based rechargeable batteries.

Lithium-ion battery (LIBs) system is one the most widely used energy storage systems in today’s renewable energy field. However, with the dramatically increased demand over the past decades and limited core material storage, concerns arise regarding its sustainability and large-scale applications. While trying to make more efficient LIBs, the studies of alternative battery systems also appear to be more and more critical. Among many newly studied battery systems, Potassium-ion batteries (PIBs) have caught our attention. With the advantage of high abundance of Potassium (K) and low redox potential of K/K+ (2.93 V vs. standard hydrogen electrode), it appears to be a perfect candidate for substituting many of the current LIBs applications. However, the absence of a suitable carbon anode has hindered the development of PIBs. Herein, we used low-cost and abundant soybean as base material and developed a high-performance hard carbon anode for PIBs. Hard carbon, produced with 500 degrees process, exhibited the highest discharge capacity of 225 mA h g-1, long lifetime of 900 cycles, and good rate capability. Benefited from low activation temperature, the soybean-derived carbon has a medium surface area, large interplanar spacing graphene layers and low degree of graphitization, which are favored by the adsorption-dominated K-ion storage mechanism. To further improve the anode efficiency, a thin layer of Al2O3 coating (~ 2 nm) was applied on the hard carbon by Atomic Layer Deposition (ALD) to function as artificial solid electrolyte interphase and increased the Coulombic efficiency from 99.0% to 99.6%. After investigating the relationship among electrochemical performance, material interface, structural design, and mechanism of potassium-ion storage, we provided new insights for the design and synthesis of carbonaceous materials with improved storage capacity and efficiency for future developments of PIBs.

Lately discovered silver selenide (Ag2Se) colloidal quantum dots with tetragonal crystal structure exhibit promising optical properties in the mid-wavelength infrared. Although colloidal synthesis of uniform sizes and shapes as well as detailed phase transformation and photoluminescence properties have been studied recently, investigations of their optoelectronic properties as an active layer in photodetector devices remain scarce. Herein, we present the fabrication and characterization of Ag2Se colloidal quantum dot-based photoconductive photodetectors. We investigate the effect of ligand exchange as well as temperature and spectral-dependent photoresponses. Our results suggest that further enhancement in performance could be achieved through accurate control of carrier concentration. With this improvement, Ag2Se colloidal quantum dots may serve as a promising mid-wavelength infrared absorber for the development of thermal infrared sensors and imagers with low size, weight, power consumption, and cost.

Cu2Se thin films provide a promising route toward relatively safe, sustainable and solution processed thermoelectric (TE) modules in contrast to more expensive and toxic materials currently on the ...

The ability to perform laboratory testing near the patient and with smaller blood volumes would benefit patients and physicians alike. We describe our design of a miniaturized clinical laboratory system with three components: a hardware platform (ie, the miniLab) that performs preanalytical and analytical processing steps using miniaturized sample manipulation and detection modules, an assay-configurable cartridge that provides consumable materials and assay reagents, and a server that communicates bidirectionally with the miniLab to manage assay-specific protocols and analyze, store, and report results (i.e., the virtual analyzer). The miniLab can detect analytes in blood using multiple methods, including molecular diagnostics, immunoassays, clinical chemistry, and hematology. Analytical performance results show that our qualitative Zika virus assay has a limit of detection of 55 genomic copies/ml. For our anti-herpes simplex virus type 2 immunoglobulin G, lipid panel, and lymphocyte subset panel assays, the miniLab has low imprecision, and method comparison results agree well with those from the United States Food and Drug Administration-cleared devices. With its small footprint and versatility, the miniLab has the potential to provide testing of a range of analytes in decentralized locations.

Tellurium (Te) is a rising electrode material for rechargeable batteries due to its prominent electrical conductivity (2 × 102 S m−1) and high volumetric capacity (2621 mAh cm−3). Currently, Li-Te batteries are mainly challenged by the large volume change accompanied by the redox conversion between Te and Li2Te. Herein, the abundant lignin is utilized to develop porous carbon as the Te host through carbonization and activation treatment. Our study reveals that both pore volume and surface area increase with the activation temperature and the different pore structure leads to the entirely different electrochemical performance of Te/C electrodes. It is found that an ideal porous carbon should possess a majority of micropores to confine Te and accommodate its volume change and a small portion of mesopores to facilitate electrolyte wetting and Li-ion transport. The optimized Te/C electrode delivers a reversible capacity of 418 mAh g−1, high capacity retention of 90% after 100 cycles, and exceptional cyclability over 1000 cycles at 2 C. This work suggests that lignin is a sustainable precursor for developing a unique carbon pore structure in battery applications.

C. neoformans, is one of the top 3 fungal pathogens, causing disseminated disease with high mortality in the absence of immunoprotecion. The protective Th1 immune response leads to M1 macrophage polarization that upregulates inducible nitric oxide synthase (iNOS) generating microbicidal nitric oxide. The role of iNOS has been studied in pulmonary defenses to C. neoformans, while its role in disseminated infection remains unknown. Here we study the effect of iNOS deletion in mouse model of disseminated cryptococcosis. The iNOS−/− and the WT, C57BL/6 mice were infected with 106 CFU of C. neoformans 52D via retro-orbital intravenous inoculation. Infected iNOS−/− mice showed significantly reduced survival times, however, they lacked significant increases in fungal burdens in the common infection sites (lung, spleen and CNS). Interestingly, iNOS deletion resulted in nearly 100-fold increase of the kidney fungal burden. Kidney histology revealed extensive lesions resulting in almost complete destruction of the kidney cortical area in iNOS−/− mice and a corresponding loss of kidney function was observed. The lack of fungal control was not due to a failure to recruit immune cells as iNOS−/− mice had increased kidney leukocyte recruitment as well as increases in monocytes and neutrophils. BMDMs from iNOS−/− mice were able to kill Cryptococcus despite a slight M2 bias seen in vivo. iNOS−/− mice had no defect in T-cell polarization, but a slight decrease in surface markers of activation. We conclude that iNOS expression is particularly important for local fungal control in kidneys, although its deletion does not induce a shift in a systemic immunophenotype in the iNOS−/− mice; rather it serves as an effector molecule in a local kidney environment.

Potassium-ion batteries (KIBs) are an attractive energy storage system for large-scale applications, due to the high abundance of potassium (K) and low redox potential of K/K+. However, the development of KIBs has been hindered by the absence of a suitable carbon anode. Herein, we developed a high-performance hard carbon anode for KIBs by using low-cost and abundant soybeans as the starting material. The hard carbon obtained at 500 °C exhibited the highest discharge capacity of 225 mA h g−1, good rate capability, and long lifetime of 900 cycles. Low activation temperature yielded hard carbon with medium surface area, large interplanar spacing of graphene layers, and low degree of graphitization, which favored adsorption-dominated K-ion storage mechanism and were considered as the key merits for the soybeans-derived carbon anode for KIBs. Moreover, a thin Al2O3 coating (~2 nm) by atomic layer deposition was used as an artificial solid electrolyte interphase on hard carbon, and improved the average Coulombic efficiency from 99.0% to 99.6%. Clarification on the correlation among electrochemical performance, structural and physical properties, and K-ion storage mechanism of hard carbon provides new insights critical for knowledge-based design and synthesis of carbonaceous materials with improved K-ion storage capacity and efficiency for practical KIBs.

Sodium-selenium (Na–Se) batteries are promising energy storage systems due to their relatively low cost and high volumetric energy density of Se cathode. However, the practical application of Na–Se batteries has been hindered by the polyselenides dissolution (or shuttle effect phenomena), which could cause low Coulombic efficiency and poor cycling lifetime. Herein, we addressed the polyselenides dissolution by using microporous carbon (MPC) derived from poly (vinylidene fluoride) as the Se host and fluoroethylene carbonate (FEC) as the additive in the electrolyte. The MPC/Se cathode with 3% FEC additive maintained a specific capacity of 382 and 350 mAh g−1 in the 100th and 200th cycle, respectively, while the MPC/Se cathode without FEC could only deliver 317 and 245 mAh g−1 after 100 and 200 cycles, respectively. Another important finding was that the use of FEC additive could prevent the corrosion of Na metal anode from soluble polyselenides, and preserve the structural integrity of Na anode, contributing to the enhanced cycling stability and specific capacity of Na–Se batteries. It is expected that this work could draw researchers’ attention to the importance of reporting and studying Na metal anode while optimizing Se cathode for Na–Se batteries.

This paper presents a method of analysis of grounding systems located inside or near a hemi-oblate spheroidal soil heterogeneity. This type of soil is particularly useful for modeling grounding grids close to certain types of finite inhomogeneities, such as lakes or some types of backfill materials. The developed analytical framework is based on a moment method and involves solving Poisson's equation in an oblate spheroidal coordinate system. Computation results obtained using this modeling approach for several electrodes and hemispheroidal geometries are compared with those obtained using other numerical and analytical techniques. In all cases, good agreement has been achieved.

The ability to perform laboratory testing near the patient and with smaller blood volumes would benefit patients and physicians alike. We describe our design of a miniaturized clinical laboratory system with three components: a hardware platform (ie, the miniLab) that performs preanalytical and analytical processing steps using miniaturized sample manipulation and detection modules, an assay‐configurable cartridge that provides consumable materials and assay reagents, and a server that communicates bidirectionally with the miniLab to manage assay‐specific protocols and analyze, store, and report results (i.e., the virtual analyzer). The miniLab can detect analytes in blood using multiple methods, including molecular diagnostics, immunoassays, clinical chemistry, and hematology. Analytical performance results show that our qualitative Zika virus assay has a limit of detection of 55 genomic copies/ml. For our anti‐herpes simplex virus type 2 immunoglobulin G, lipid panel, and lymphocyte subset panel assays, the miniLab has low imprecision, and method comparison results agree well with those from the United States Food and Drug Administration‐cleared devices. With its small footprint and versatility, the miniLab has the potential to provide testing of a range of analytes in decentralized locations.

Lithium-selenium (Li–Se) batteries represent a promising energy storage system due to the relatively high electronic conductivity and high volumetric energy density of Se as a cathode. The design of porous carbon with tunable structure and low cost is a key to enabling Se cathodes for high-performance Li–Se batteries. In this study, hierarchically microporous activated carbon (AC) was fabricated from waste coffee grounds through a carbonization and KOH-activation process. Despite the simple synthesis process, the optimized AC (AC-700) had a high surface area of 1355 m2 g−1 and a large microspore volume of 0.52 cm³ g−1. The Se/AC-700 cathode showed a reversible capacity of 655 mAh g−1 after 100 cycles at 0.1C in Li–Se batteries based on a carbonate electrolyte. Moreover, the Se/AC-700 cathode demonstrated excellent cyclic performance over 400 cycles without appreciable capacity decay. The main reason for the good battery performance was attributed to fast electron transfer and Li-ion diffusion in Se confined in the microporous carbon of AC-700. It is expected that this work will shed light on the development of low-cost and stable Se cathodes for high-energy Li–Se batteries.

The roles and actions of the tumor suppressor protein p53 have been extensively studied with regard to nuclear events, including transcription and DNA damage repair. However, the direct roles of p53 in mitochondrial DNA (mtDNA) replication and function are less well understood. Studies herein used a mitochondrial-targeted p53 (MTS-p53) to determine its effects on both mtDNA abundance and mitochondrial function. MTS-p53 decreased cellular proliferation and mtDNA abundance in HepG2 cells transfected with wild-type (WT) human p53. When MTS-p53 cells were treated with the nucleoside reverse transcriptase inhibitor (NRTI), 2′,3′-dideoxycytidine or 2′,3′-dideoxyinosine, mtDNA depletion that resembled untransfected controls was observed in both instances. p53-Overexpressing cells showed reduced mitochondrial function by oximetry, including a reduction in maximal respiratory capacity and reserve capacity. A truncated p53 (MTS-p53-290) was generated for localization exclusively to the mitochondria. MTS-p53-290 cells proliferated at control levels but displayed decreased mtDNA abundance and mitochondrial function with NRTI treatment. The MTS-p53-290 cells demonstrated that only the nuclear fraction of p53 controlled cellular proliferation, which was supported by the MTS-p53 results. Data herein indicate that overexpression of p53 in the mitochondria reduces mtDNA abundance and increases the sensitivity of mammalian cells to NRTI exposure by reducing mitochondrial function.

We present single-molecule, real-time sequencing data obtained from a DNA polymerase performing uninterrupted template-directed synthesis using four distinguishable fluorescently labeled deoxyribonucleoside triphosphates (dNTPs). We detected the temporal order of their enzymatic incorporation into a growing DNA strand with zero-mode waveguide nanostructure arrays, which provide optical observation volume confinement and enable parallel, simultaneous detection of thousands of single-molecule sequencing reactions. Conjugation of fluorophores to the terminal phosphate moiety of the dNTPs allows continuous observation of DNA synthesis over thousands of bases without steric hindrance. The data report directly on polymerase dynamics, revealing distinct polymerization states and pause sites corresponding to DNA secondary structure. Sequence data were aligned with the known reference sequence to assay biophysical parameters of polymerization for each template position. Consensus sequences were generated from the single-molecule reads at 15-fold coverage, showing a median accuracy of 99.3%, with no systematic error beyond fluorophore-dependent error rates.

We investigated phosphorus and boon implanted emitter and selective emitter junction formation comparing; 1) 15keV to 30keV implant energies, 2) implant dopant dose concentration between 3E14/cm2 to 1E16/cm2 and 3) various anneal conditions from high temperature (>1407°C) laser melt annealing to low temperature (