Self-assembled nanonization of fatty acid-conjugated vaccine antigen for enhanced thermal stability.

The aim of this study was to evaluate the enhanced thermal stability and physicochemical properties of fattigated vaccine antigens. High molecular weight influenza hemagglutinin (Heg) was used as a model antigen because of low heat stability requiring cold chamber. Heg was conjugated with long-chain oleic acid (C18) and short-chain 3-decenoic acid (C10) to prepare fattigated Heg. Circular dichroism analysis revealed no significant changes in the three-dimensional structure post-conjugation. In the liquid state, the fattigated Heg was self-assembled into nanoparticles (NPs) due to its amphiphilic nature, with sizes of 136.27 ± 12.78 nm for oleic acid-conjugated Heg (HOC) and 88.73 ± 3.27 nm for 3-decenoic acid-conjugated Heg (HDC). Accelerated thermal stability studies at 60 °C for 7 days demonstrated that fattigated Heg exhibited higher thermal stability than Heg in various liquid or solid states. The longer-chained HOC showed better thermal stability than HDC in the liquid state, attributed to increased hydrophobic interactions during self-assembly. In bio-mimicking liquid states at 37 °C, HOC exhibited higher thermal stability than Heg. Furthermore, solid-state HOC with cryoprotectants (trehalose, mannitol, and Tween® 80) had significantly increased thermal stability due to reduced exposure of protein surface area via nanonization behavior. The current fattigation platform could be a promising strategy for developing thermostable nano vaccines of heat-labile vaccine antigens.

Defects Healing of the ZnO Surface by Filling with Au Atom Catalysts for Efficient Photocatalytic H2 Production.

Healed defects on photocatalysts surface and their interaction with plasmonic nanoparticles (NPs) have attracted attention in H2 production process. In this study, surface oxygen vacancy (Vo ) defects are created on ZnO (Vo -ZnO) NPs by directly pyrolyzing zeolitic imidazolate framework. The surface defects on Vo -ZnO provide active sites for the diffusion of single Au atoms and as nucleation sites for the formation of Au NPs by the in situ photodeposition process. The electronically healed surface defects by single Au atoms help in the formation of a heterojunction between the ZnO and plasmonic Au NPs. The formed Au/Vo -Au:ZnO-4 heterojunction prolongs photoelectron lifetimes and increases donor charge density. Therefore, the optimized photocatalysts of Au/Vo -Au:ZnO-4 has 21.28 times higher H2 production rate than the pristine Vo -ZnO under UV-visible light in 0.35 m Na2 SO4 and 0.25 m Na2 SO3 . However in 0.35 m Na2 S and 0.25 m Na2 SO3 , the H2 production rate is 25.84 mmole h-1 g-1 . Furthermore, Au/Vo -Au:ZnO-4 shows visible light activity by generating hot carries via induced surface plasmonic effects. It has 48.58 times higher H2 production rate than pristine Vo -ZnO. Therefore, this study infers new insight for defect healing mediated preparation of Au/Vo -Au:ZnO heterojunction for efficient photocatalytic H2 production.

Actigraphic evidence of persistent sleep disruption following repetitive mild traumatic brain injury in a gyrencephalic model.

We studied the effect of multimodal traumatic brain injuries on daily sleep/activity patterns and related histology. Gyrencephalic ferrets wore actigraphs and received military-relevant brain injuries including shockwaves, strong rotational impact, and variable stress, which were evaluated up to 6 months post injury. Sham and Baseline animals exhibited activity patterns occurring in distinct clusters of high activity, interspersed with periods of low activity. In the Injury and Injury + Stress groups, activity clusters diminished and overall activity patterns became significantly more dispersed at 4 weeks post injury with significant sleep fragmentation. Additionally, the Injury + Stress group exhibited a significant decrease in daytime high activity up to 4 months post injury. At 4 weeks post injury, the reactive astrocyte (GFAP) immunoreactivity was significantly greater in both the injury groups compared to Sham, but did not differ at 6 months post injury. The intensity of immunoreactivity of the astrocytic endfeet that surround blood vessels (visualized with aquaporin 4; AQP4), however, differed significantly from Sham at 4 weeks post injury (in both injured groups) and at 6 months (Injury + Stress only). As the distribution of AQP4 plays a key role in the glymphatic system, we suggest that glymphatic disruption occurs in ferrets after the injuries described here.

Sprayed FeWO4 thin film-based memristive device with negative differential resistance effect for non-volatile memory and synaptic learning applications.

Resistive switching (RS) memories have attracted great attention as promising solutions to next-generation non-volatile memories and computing technologies because of their simple device configuration, high on/off ratio, low power consumption, fast switching, long retention, and significant cyclic stability. In this work, uniform and adherent iron tungstate (FeWO4) thin films were synthesized by the spray pyrolysis method with various precursor solution volumes, and these were tested as a switching layer for the fabrication of Ag/FWO/FTO memristive devices. The detailed structural investigation was done through various analytical and physio-chemical characterizations viz. X-ray diffraction (XRD) and its Rietveld refinement, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) techniques. The results reveal the pure and single-phase FeWO4 compound thin film formation. Surface morphological study shows the spherical particle formation having a diameter in the range of 20 to 40 nm. The RS characteristics of the Ag/FWO/FTO memristive device demonstrate non-volatile memory characteristics with significant endurance and retention properties. Interestingly, the memory devices show stable and reproducible negative differential resistance (NDR) effects. The in-depth statistical analysis suggests the good operational uniformity of the device. Moreover, the switching voltages of the Ag/FWO/FTO memristive device were modeled using the time series analysis technique by utilizing Holt's Winter Exponential Smoothing (HWES) approach. Additionally, the device mimics bio-synaptic properties such as potentiation/depression, excitatory post-synaptic current (EPSC), and spike-timing-dependent plasticity (STDP) learning rules. For the present device, the space-charge-limited current (SCLC) and trap-controlled-SCLC effects dominated during positive and negative bias I-V characteristics, respectively. The RS mechanism dominated in the low resistance state (LRS), and the high resistance state (HRS) was explained based on the formation and rupture of conductive filament composed of Ag ions and oxygen vacancies. This work demonstrates the RS in the metal tungstate-based memristive devices and demonstrates a low-cost approach for fabricating memristive devices.

Persistent hypersomnia following repetitive mild experimental traumatic brain injury: Roles of chronic stress and sex differences.

Traumatic brain injury (TBI) is often more complicated than a single head injury. An extreme example of this point may be military service members who experience a spectrum of exposures over a prolonged period under stressful conditions. Understanding the effects of complex exposures can inform evaluation and care to prevent persistent symptoms. We designed a longitudinal series of non-invasive procedures in adult mice to evaluate the effects of prolonged mild stress and head injury exposures. We assessed anxiety, depression, and sleep-wake dysfunction as symptoms that impact long-term outcomes after mild TBI. Unpredictable chronic mild stress (UCMS) was generated from a varied sequence of environmental stressors distributed within each of 21 days. Subsequently, mice received a mild blast combined with closed-head mild TBI on 5 days at 24-h intervals. In males and females, UCMS induced anxiety without depressive behavior. A major finding was reproducible sleep-wake dysfunction through 6- to 12-month time points in male mice that received UCMS with repetitive blast plus TBI events, or surprisingly after just UCMS alone. Specifically, male mice exhibited hypersomnia with increased sleep during the active/dark phase and fragmentation of longer wake bouts. Sleep-wake dysfunction was not found with TBI events alone, and hypersomnia was not found in females under any conditions. These results identify prolonged stress and sex differences as important considerations for sleep-wake dysfunction. Furthermore, this reproducible hypersomnia with impaired wakefulness is similar to the excessive daytime sleepiness reported in patients, including patients with TBI, which warrants further clinical screening, care, and treatment development.

Development of a novel bioengineered 3D brain-like tissue for studying primary blast-induced traumatic brain injury.

Primary blast injury is caused by the direct impact of an overpressurization wave on the body. Due to limitations of current models, we have developed a novel approach to study primary blast-induced traumatic brain injury. Specifically, we employ a bioengineered 3D brain-like human tissue culture system composed of collagen-infused silk protein donut-like hydrogels embedded with human IPSC-derived neurons, human astrocytes, and a human microglial cell line. We have utilized this system within an advanced blast simulator (ABS) to expose the 3D brain cultures to a blast wave that can be precisely controlled. These 3D cultures are enclosed in a 3D-printed surrogate skull-like material containing media which are then placed in a holder apparatus inside the ABS. This allows for exposure to the blast wave alone without any secondary injury occurring. We show that blast induces an increase in lactate dehydrogenase activity and glutamate release from the cultures, indicating cellular injury. Additionally, we observe a significant increase in axonal varicosities after blast. These varicosities can be stained with antibodies recognizing amyloid precursor protein. The presence of amyloid precursor protein deposits may indicate a blast-induced axonal transport deficit. After blast injury, we find a transient release of the known TBI biomarkers, UCHL1 and NF-H at 6 h and a delayed increase in S100B at 24 and 48 h. This in vitro model will enable us to gain a better understanding of clinically relevant pathological changes that occur following primary blast and can also be utilized for discovery and characterization of biomarkers.

Limbic Responses Following Shock Wave Exposure in Male and Female Mice.

Blast traumatic brain injury (bTBI) presents a serious threat to military personnel and often results in psychiatric conditions related to limbic system dysfunction. In this study, the functional outcomes for anxiety- and depressive-like behaviors and neuronal activation were evaluated in male and female mice after exposure to an Advanced Blast Simulator (ABS) shock wave. Mice were placed in a ventrally exposed orientation inside of the ABS test section and received primary and tertiary shock wave insults of approximately 15 psi peak pressure. Evans blue staining indicated cases of blood-brain barrier breach in the superficial cerebral cortex four, but not 24 h after blast, but the severity was variable. Behavioral testing with the elevated plus maze (EPM) or elevated zero maze (EZM), sucrose preference test (SPT), and tail suspension test (TST) or forced swim test (FST) were conducted 8 days-3.5 weeks after shock wave exposure. There was a sex difference, but no injury effect, for distance travelled in the EZM where female mice travelled significantly farther than males. The SPT and FST did not indicate group differences; however, injured mice were less immobile than sham mice during the TST; possibly indicating more agitated behavior. In a separate cohort of animals, the expression of the immediate early gene, c-Fos, was detected 4 h after undergoing bTBI or sham procedures. No differences in c-Fos expression were found in the cerebral cortex, but female mice in general displayed enhanced c-Fos activation in the paraventricular nucleus of the thalamus (PVT) compared to male mice. In the amygdala, more c-Fos-positive cells were observed in injured animals compared to sham mice. The observed sex differences in the PVT and c-Fos activation in the amygdala may correlate with the reported hyperactivity of females post-injury. This study demonstrates, albeit with mild effects, behavioral and neuronal activation correlates in female rodents after blast injury that could be relevant to the incidence of increased post-traumatic stress disorder in women.

Transposition of insertion sequences by dielectric barrier discharge plasma and gamma irradiation in the radiation-resistant bacterium Deinococcus geothermalis.

Insertion sequences (ISs) of the radiation-resistant bacterium Deinococcus geothermalis are transposed into other loci by oxidative stress through hydrogen peroxide treatment. Gamma irradiation and dielectric barrier discharge (DBD) plasma radiation are known to produce a variety of oxidative stress agents such as reactive oxygen species and reactive nitrogen species. Therefore, to determine whether the transposition of ISs was induced in D. geothermalis by both gamma irradiation and DBD plasma radiation, we selected non-pigmented mutants with disrupted target genes encoding carotenoid biosynthesis enzymes such as a phytoene synthase (dgeo_0523) and a phytoene desaturase (dgeo_0524). Different DNA-binding protein-deficient mutants exhibited novel transposition of ISs. Dps (dgeo_0257), OxyR (dgeo_1888), and the LysR (dgeo_2840) family regulator, in addition to cystine importer-disrupted and -overexpressed mutants (dgeo_1986-87 and dgeo_1985R) and wild-type D. geothermalis were tested in this study. Active IS transposition was not detected in two wild-type control species (Deinococcus radiodurans and Deinococcus radiopugnans) after phenotypic selection in gamma irradiation. Our finding demonstrated that gamma irradiation triggers the transposition of particular IS elements, especially ISDge2 and ISDge3 of the IS1 family, ISDge5 of the IS701 family, and ISDge6 of the IS5 family in wild-type strain and the Δdgeo_0257, Δdgeo_1986-87, Δdgeo_1985R, and Δdgeo_2840 mutants. Furthermore, DBD plasma radiation triggered the transposition of ISDge11 of the IS4 family in the wild-type strain; ISDge6 of the IS5 family on Δdgeo_0257, Δdgeo_1888 and Δdgeo_2840; ISDge5 of the IS701 family on Δdgeo_0257 strain.

PIM-PI-1 and Poly(ethylene glycol)/Poly(propylene glycol)-Based Mechanically Robust Copolyimide Membranes with High CO2-Selectivity and an Anti-aging Property: A Joint Experimental-Computational Exploration.

Polymer membranes with excellent thermomechanical properties and good gas separation performance are desirable for efficient CO2 separation. A series of copolyimide membranes are prepared for the first time using PIM-PI-1, a hard segment with high CO2 permeability, and poly(ethylene glycol)/poly(propylene glycol) (PEG/PPG), a soft segment with high CO2 selectivity. Two different unit polymers are combined to compensate the limitations of each polymer (e.g., the fast aging and moderate selectivity of PIM-PI-1 and the poor mechanical properties and lower permeability of PEG/PPG). The corresponding PIM-(durene-PEG/PPG) membranes exhibit an excellent combination of mechanical properties and gas separation performance compared to the typical PI-PEG-based copolymer membrane. The improved mechanical property is attributed to the unique chain threading and the reinforcement between the spiro unit of PIM and the flexible PEG/PPG at the molecular level, which has not previously been exploited for membranes. The PIM-(durene-PEG/PPG) membranes show a high CO2 permeability of 350-669 Barrer and a high CO2/N2 selectivity of 33.5-40.3. The experimental results are further evaluated with theoretical results obtained from molecular simulation studies, and a very good agreement between the experimental results and simulation results is found. Moreover, the PIM-(durene-PEG/PPG) copolymer membranes display excellent anti-aging performance for up to 1 year.

The Fate of Lumbar Facet Cyst After Indirect Decompression Using Oblique Lateral Interbody Fusion in Degenerative Spondylolisthesis.

Favorable clinical outcomes have been reported for oblique lateral interbody fusion (OLIF) for various lumbar degenerative diseases. However, there is only limited evidence on the safety and effectiveness of OLIF in degenerative spondylolisthesis with lumbar facet cyst (LFC), and OLIF is often regarded as a relative contraindication for these patients. The authors prospectively enrolled patients who underwent a single-level OLIF for degenerative spondylolisthesis with LFC to evaluate the morphological changes of LFC and their clinical significance following OLIF. Twenty patients with a mean age of 69.6 years (range, 65-86 years) were enrolled. At 1 week postoperative, 5 (25%) patients had a residual cyst, whereas 15 (75%) patients had completely resolved cysts on magnetic resonance imaging (MRI). No patient had a residual cyst on the 1-year postoperative MRI. Patients with cyst resolution (n=15) on the 1-week postoperative MRI had a larger slip percentage difference on the preoperative dynamic radiograph when compared with patients with no cyst resolution (n=5) (4.7%±2.8% vs 1.3%±0.3%, P=.002). The group with cyst resolution also showed a greater expansion of facet fluid width following OLIF, although this was not statistically significant (1.2±0.7 mm vs 0.7±0.5 mm, P=.098). For both groups, all preoperative clinical scores showed a significant improvement at 1 year after OLIF, but there was no significant difference between the groups at all time points. Preliminary 1-year follow-up results from this prospective series suggest that OLIF can be a useful option for fusion surgery in LFC patients with apparent segmental instability. [Orthopedics. 2021;44(5):306-312.].

Modified Graphene Oxide-Incorporated Thin-Film Composite Hollow Fiber Membranes through Interface Polymerization on Hydrophilic Substrate for CO2 Separation.

Thin-film composite mixed matrix membranes (CMMMs) were fabricated using interfacial polymerization to achieve high permeance and selectivity for CO2 separation. This study revealed the role of substrate properties on performance, which are not typically considered important. In order to enhance the affinity between the substrate and the coating solution during interfacial polymerization and increase the selectivity of CO2, a mixture of polyethylene glycol (PEG) and dopamine (DOPA) was subjected to a spinning process. Then, the surface of the substrate was subjected to interfacial polymerization using polyethyleneimine (PEI), trimesoyl chloride (TMC), and sodium dodecyl sulfate (SDS). The effect of adding SDS as a surfactant on the structure and gas permeation properties of the fabricated membranes was examined. Thin-film composite hollow fiber membranes containing modified graphene oxide (mGO) were fabricated, and their characteristics were analyzed. The membranes exhibited very promising separation performance, with CO2 permeance of 73 GPU and CO2/N2 selectivity of 60. From the design of a membrane substrate for separating CO2, the CMMMs hollow fiber membrane was optimized using the active layer and mGO nanoparticles through interfacial polymerization.

Repetitive Blast Exposure Produces White Matter Axon Damage without Subsequent Myelin Remodeling: In Vivo Analysis of Brain Injury Using Fluorescent Reporter Mice.

The potential effects of blast exposure on the brain health of military personnel have raised concerns and led to increased surveillance of blast exposures. Neuroimaging studies have reported white matter abnormalities in brains of service members with a history of blast exposure. However, blast effects on white matter microstructure remain poorly understood. As a novel approach to screen for white matter effects, transgenic mice that express fluorescent reporters to sensitively detect axon damage and myelin remodeling were exposed to simulated repetitive blasts (once/day on 5 consecutive days). Axons were visualized using Thy1-YFP-16 reporter mice that express yellow fluorescent protein (YFP) in a broad spectrum of neurons. Swelling along damaged axons forms varicosities that fill with YFP. The frequency and size of axonal varicosities were significantly increased in the corpus callosum (CC) and cingulum at 3 days after the final blast exposure, versus in sham procedures. CC immunolabeling for reactive astrocyte and microglial markers was also significantly increased. NG2CreER;mTmG mice were given tamoxifen (TMX) on days 2 and 3 after the final blast to induce fluorescent labeling of newly synthesized myelin membranes, indicating plasticity and/or repair. Myelin synthesis was not altered in the CC over the intervening 4 or 8 weeks after repetitive blast exposure. These experiments show the advantages of transgenic reporter mice for analysis of white matter injury that detects subtle, diffuse axon damage and the dynamic nature of myelin sheaths. These results show that repetitive low-level blast exposures produce infrequent but significant axon damage along with neuroinflammation in white matter.

Polydopamine Films with 2D-like Layered Structure and High Mechanical Resilience.

Highly oriented, layered, and mechanically resilient films of polydopamine (PDA) have been synthesized from the air/water interface. The films show a unique layered structure, as shown by scanning and transmission electron studies (SEM/TEM) and X-ray diffraction analysis (XRD), which resemble that of 2D layered materials. The films exhibit a composition typical of PDA-based materials, as evidenced by X-ray photoelectron spectroscopy (XPS); moreover, the samples present the distinctive resonance modes of PDA-based nanomaterials in Raman and infrared spectroscopy (FTIR) experiments. The presence of highly ordinated 3-4 protomolecule stacking, taking place at the air/water interface, with a unique eumelanin-like supramolecular arrangement is presented. Moreover, the films show superior mechanical resilience with E = 13 ± 4 GPa and H = 0.21 ± 0.03 GPa, as revealed by nanoindentation experiments, making them highly resilient and easily transferable. Finally, the ordering induced by the interface opens many possibilities for further studies, including those regarding the supramolecular structure on PDA due to their similarity to 2D layered materials.

Sagittal Alignment in Patients with Thoracic Myelopathy Caused by the Ossification of the Ligamentum Flavum: A Retrospective Matched Case-Control Study.

STUDY DESIGN: Retrospective case-control study. OBJECTIVE: The aim of this study was to describe and compare the sagittal spinal alignment between patients with and without the ossification of the ligamentum flavum in the thoracic spine (TOLF). SUMMARY OF BACKGROUND DATA: Although mechanical factors play an important role in the development of TOLF, limited evidence exists on the association of sagittal spinal alignment and TOLF in the literature. METHODS: The present study assessed the preoperative sagittal alignment parameters in consecutive patients who underwent posterior decompression for TOLF in a single institution between January 2014 and December 2019. The sagittal parameters of the patients with TOLF were compared to those of the age- and sex-matched control group with lumbar spondylosis. RESULTS: The TOLF group (n = 43 [23 men, 20 women]), with a mean age of 69.5 (range: 41-86) years, and the control group (n = 86) were compared. The TOLF group had a significantly smaller sacral slope (27.60 ±â€Š7.49 vs. 30.61 ±â€Š8.15, P = 0.045) and lumbar lordosis (36.84 ±â€Š13.63 vs. 45.08 ±â€Š9.90, P < 0.001) and a larger pelvic incidence minus lumbar lordosis (PI-LL, 8.06 ±â€Š15.05 vs.1.00 ±â€Š11.34, P = 0.004) than the control group. Moreover, the thoracic kyphosis was smaller in the TOLF group, although the difference was not statistically significant (25.73 ±â€Š11.29 vs. 28.22 ±â€Š9.34, P = 0.187). The TOLF group had a significantly smaller slope angle at the inflection point (11.97 ±â€Š5.85 vs. 15.78 ±â€Š5.62, P < 0.001) and a higher tendency to have a Roussouly type 2 morphology (46.5% vs. 36.0%, P = 0.252) than the control group. CONCLUSION: This is the first study to describe the sagittal alignment in patients with TOLF. The TOLF group showed a hypolordotic spine with a larger PI-LL mismatch compared to the age- and sex-matched control group with lumbar spondylosis.Level of Evidence: 4.

Behavioral and Myelin-Related Abnormalities after Blast-Induced Mild Traumatic Brain Injury in Mice.

In civilian and military settings, mild traumatic brain injury (mTBI) is a common consequence of impacts to the head, sudden blows to the body, and exposure to high-energy atmospheric shockwaves from blast. In some cases, mTBI from blast exposure results in long-term emotional and cognitive deficits and an elevated risk for certain neuropsychiatric diseases. Here, we tested the effects of mTBI on various forms of auditory-cued fear learning and other measures of cognition in male C57BL/6J mice after single or repeated blast exposure (blast TBI; bTBI). bTBI produced an abnormality in the temporal organization of cue-induced freezing behavior in a conditioned trace fear test. Spatial working memory, evaluated by the Y-maze task performance, was also deleteriously affected by bTBI. Reverse-transcription quantitative real-time polymerase chain reaction (RT-qPCR) analysis for glial markers indicated an alteration in the expression of myelin-related genes in the hippocampus and corpus callosum 1-8 weeks after bTBI. Immunohistochemical and ultrastructural analyses detected bTBI-related myelin and axonal damage in the hippocampus and corpus callosum. Together, these data suggest a possible link between blast-induced mTBI, myelin/axonal injury, and cognitive dysfunction.

Dual-functional micro-adsorbents: Application for simultaneous adsorption of cesium and strontium.

In current work, Prussian blue (PB)- and hydroxyapatite (HAp)-embedded micro-adsorbents (PB-HAp-MAs) were rationally fabricated through an easy and flexible custom-made micronozzle system as a novel bifunctional adsorbent. The adsorption performance of the as-prepared samples was conducted based on the removal of cesium (Cs+) and strontium (Sr2+) ions. Adsorption behaviors of the PB-HAp-MAs were also evaluated as function extrusion dimensions and adsorbate concentration. The adsorption isotherm was well fitted by the Langmuir model with adsorption capacities of 24.688 mg g-1 and 29.254 mg g-1 for Cs+ and Sr2+, respectively. Specially, the enhanced adsorption activity can be synergistically attributed to the porous nature of the developed alginate backbone with a high surface area of encapsulated functional nanoparticles, thus leading to rapid saturation within 1 min. In addition, the as-synthesized PB-HAp-MAs were successfully separated from the aqueous solution within 10 s by applying a magnetic field. We expect that our findings will provide valuable guidelines towards developing highly efficient adsorbents for environmental remediation.

A conductive self healing polymeric binder using hydrogen bonding for Si anodes in lithium ion batteries.

A ureido-pyrimidinone (UPy)-functionalized poly(acrylic acid) grafted with poly(ethylene glycol)(PEG), designated PAU-g-PEG, was developed as a high performance polymer binder for Si anodes in lithium-ion batteries. By introducing both a ureido-pyrimidinone (UPy) unit, which is capable of self-healing through dynamic hydrogen bonding within molecules as well as with Si, and an ion-conducting PEG onto the side chain of the poly(acrylic acid), this water-based self-healable and conductive polymer binder can effectively accommodate the volume changes of Si, while maintaining electronic integrity, in an electrode during repeated charge/discharge cycles. The Si@PAU-g-PEG electrode retained a high capacity of 1,450.2 mAh g-1 and a Coulombic efficiency of 99.4% even after 350 cycles under a C-rate of 0.5 C. Under a high C-rate of 3 C, an outstanding capacity of 2,500 mAh g-1 was also achieved, thus demonstrating its potential for improving the electrochemical performance of Si anodes.

PEG/PPG-PDMS-Adamantane-based Crosslinked Terpolymer Using the ROMP Technique to Prepare a Highly Permeable and CO2-Selective Polymer Membrane.

In this study, precursor molecules based on PEG/PPG and polydimethylsiloxane (PDMS), both widely used rubbery polymers, were copolymerized with bulky adamantane into copolymer membranes. Ring-opening metathesis polymerization (ROMP) was employed during the polymerization process to create a structure with both ends crosslinked. The precursor molecules and corresponding polymer membranes were characterized using various analytical methods. The polymer membranes were fabricated using different compositions of PDMS and adamantane, to determine how the network structure affected their gas separation performance. PEG/PPG, in which CO2 is highly soluble, was copolymerized with PDMS, which has high permeability, and adamantane, which controlled the crosslinking density with a rigid and bulky structure. It was confirmed that the resulting crosslinked polymer membranes exhibited high solubility and diffusivity for CO2. Further, their crosslinked structure using ROMP technique made it possible to form good films. The membranes fabricated in the present study exhibited excellent performance, i.e., CO2 permeability of up to 514.5 Barrer and CO2/N2 selectivity of 50.9.

Boosting Visible-Light Photocatalytic Redox Reaction by Charge Separation in SnO2 /ZnSe(N2 H4 )0.5 Heterojunction Nanocatalysts.

In this work, environmentally friendly photocatalysts with attractive catalytic properties are reported that have been prepared by introducing SnO2 quantum dots (QDs) directly onto ZnSe(N2 H4 )0.5 substrates to induce advantageous charge separation. The SnO2 /ZnSe(N2 H4 )0.5 nanocomposites could be easily synthesized through a one-pot hydrothermal process. Owing to the absence of capping ligands, the attached SnO2 QDs displayed superior photocatalytic properties, generating many exposed reactive surfaces. Moreover, the addition of a specified amount of SnO2 boosted the visible-light photocatalytic activity; however, the presence of excess SnO2 QDs in the substrate resulted in aggregation and deteriorated the performance. The spectroscopic data revealed that the SnO2 QDs act as a photocatalytic mediator and enhance the charge separation within the type II band alignment system of the SnO2 /ZnSe(N2 H4 )0.5 heterojunction photocatalysts. The separated charges in the heterojunction nanocomposites promote radical generation and react with pollutants, resulting in enhanced photocatalytic performance.

Resolving Dirac electrons with broadband high-resolution NMR.

Detecting the metallic Dirac electronic states on the surface of Topological Insulators (TIs) is critical for the study of important surface quantum properties (SQPs), such as Majorana zero modes, where simultaneous probing of the bulk and edge electron states is required. However, there is a particular shortage of experimental methods, showing at atomic resolution how Dirac electrons extend and interact with the bulk interior of nanoscaled TI systems. Herein, by applying advanced broadband solid-state 125Te nuclear magnetic resonance (NMR) methods on Bi2Te3 nanoplatelets, we succeeded in uncovering the hitherto invisible NMR signals with magnetic shielding that is influenced by the Dirac electrons, and we subsequently showed how the Dirac electrons spread inside the nanoplatelets. In this way, the spin and orbital magnetic susceptibilities induced by the bulk and edge electron states were simultaneously measured at atomic scale resolution, providing a pertinent experimental approach in the study of SQPs.