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Cubic materials host high crystal symmetry and hence are not expected to support anisotropy in transport phenomena. In contrast to this common expectation, here we report an anomalous anisotropy of spin current can emerge in the (001) film of Mn3Pt, a noncollinear antiferromagnetic spin source with face-centered cubic structure. Such spin current anisotropy originates from the intertwined time reversal-odd (T -odd) and time reversal-even (T -even) spin Hall effects. Based on symmetry analyses and experimental characterizations of the current-induced spin torques in Mn3Pt-based heterostructures, we find that the spin current generated by Mn3Pt (001) exhibits exotic dependences on the current direction for all the spin components, deviating from that in conventional cubic systems. We also demonstrate that such an anisotropic spin current can be used to realize low-power spintronic applications such as the efficient field-free switching of the perpendicular magnetizations. Symmetry is an essential ingredient that governs numerous physical phenomena, including spin transport. Following this principle, spin current sources with a highly symmetric cubic structure are not expected to support anisotropic spin currents. Here, the authors demonstrate an anomalous spin current anisotropy in a cubic noncollinear antiferromagnet Mn3Pt by exploiting the combination of conventional and magnetic spin-hall effects. [ABSTRACT FROM AUTHOR]

Coronavirus disease-19 (Covid-19) pandemic have demonstrated the importantance of vaccines in disease prevention. Self-amplifying mRNA vaccines could be another option for disease prevention if demonstrated to be safe and immunogenic. Phase 1 of this randomized, double-blinded, placebo-controlled trial (N = 42) assessed the safety, tolerability, and immunogenicity in healthy young and older adults of ascending levels of one-dose ARCT-021, a self-amplifying mRNA vaccine against Covid-19. Phase 2 (N = 64) tested two-doses of ARCT-021 given 28 days apart. During phase 1, ARCT-021 was well tolerated up to one 7.5 μg dose and two 5.0 μg doses. Local solicited AEs, namely injection-site pain and tenderness were more common in ARCT-021vaccinated, while systemic solicited AEs, mainly fatigue, headache and myalgia were reported in 62.8% and 46.4% of ARCT-021 and placebo recipients, respectively. Seroconversion rate for anti-S IgG was 100% in all cohorts, except for the 1 μg one-dose in younger adults and the 7.5 μg one-dose in older adults. Anti-S IgG and neutralizing antibody titers showed a general increase with increasing dose, and overlapped with titers in Covid-19 convalescent patients. T-cell responses were also observed in response to stimulation with S-protein peptides. Taken collectively, ARCT-021 is immunogenic and has favorable safety profile for further development. [ABSTRACT FROM AUTHOR]

Remarkable potency has been demonstrated for mRNA vaccines in reducing the global burden of the ongoing COVID-19 pandemic. An alternative form of the mRNA vaccine is the self-amplifying mRNA (sa-mRNA) vaccine, which encodes an alphavirus replicase that self-amplifies the full-length mRNA and SARS-CoV-2 spike (S) transgene. However, early-phase clinical trials of sa-mRNA COVID-19 vaccine candidates have questioned the potential of this platform to develop potent vaccines. We examined the immune gene response to a candidate sa-mRNA vaccine against COVID-19, ARCT-021, and compared our findings to the host response to other forms of vaccines. In blood samples from healthy volunteers that participated in a phase I/II clinical trial, greater induction of transcripts involved in Toll-like receptor (TLR) signalling, antigen presentation and complement activation at 1 day post-vaccination was associated with higher anti-S antibody titers. Conversely, transcripts involved in T-cell maturation at day 7 post-vaccination informed the magnitude of eventual S-specific T-cell responses. The transcriptomic signature for ARCT-021 vaccination strongly correlated with live viral vector vaccines, adjuvanted vaccines and BNT162b2 1 day post-vaccination. Moreover, the ARCT-021 signature correlated with day 7 YF17D live-attenuated vaccine transcriptomic responses. Altogether, our findings show that sa-mRNA vaccination induces innate immune responses that are associated with the development of adaptive immunity from other forms of vaccines, supporting further development of this vaccine platform for clinical application. [ABSTRACT FROM AUTHOR]

A series of new hyper-cross-linked porous polymers (HCP-TTDs) were successfully prepared by the Friedel–Crafts alkylation reaction of 1, 1, 1-trimethyl-3, 3, 3-triphenyldisiloxane and formaldehyde dimethyl acetal (FDA). Nitrogen adsorption–desorption test showed that the BET specific surface areas of them were between 989 and 1285 m2 g−1. Furthermore, the prepared HCP-TTDs exhibited excellent adsorption capacities of organic dyes in aqueous solution (Malachite green: 2346 mg g−1, Congo red: 2052 mg g−1, and Rhodamine B: 1938 mg g−1). The adsorption behavior was well agreed with the pseudo-second-order model and Langmuir model. Additionally, the functionalization of HCP-TTDs could be realized by the condensation reaction of 3-(2-aminoethylamino)propyl-dimethoxymethylsilane (AAMD) and the alkali-treated porous polymer. The functionalized HCP-TTD displayed high adsorption performance for chromium ion, and the adsorption capacity was up to 76.9 mg g−1, which is higher than many reported adsorbents. Therefore, HCP-TTDs are promising candidates for the removal of dyes and chromium ion from wastewater. [ABSTRACT FROM AUTHOR]

Lactobacillus bulgaricus is an important starter culture in the dairy industry, cell lysis is negative to the high density of this strain. This work describes the response of peptidoglycan synthases and hydrolases in Lactobacillus bulgaricus sp1.1 when pH decreasing in batch culture. First, the cell lysis was investigated by measuring the cytosolic lactate dehydrogenase released to the fermentation broth, a continuous increase in extracellular lactate dehydrogenase was observed after the lag phase in batch culture. Then, the peptidoglycan hydrolases profile analyzed using the zymogram method showed that eight proteins have the ability of peptidoglycan hydrolysis, three of the eight proteins were considered to contribute lysis of L. bulgaricus sp1.1 according to the changes and extents of peptidoglycan hydrolysis. In silico analysis showed that three putative peptidoglycan hydrolases, including N-acetylmuramyl-l-Ala amidase (protein ID: ALT46642.1), amidase (protein ID: ALT46641.1), and N-acetylmuramidase (protein ID: WP_013439201.1) were compatible with these proteins. Finally, the transcription of the three putative peptidoglycan hydrolases was upregulated in batch culture, in contrast, the expression of four peptidoglycan synthases was downregulated. These observations suggested the imbalance between peptidoglycan synthases and hydrolases involved in the lysis of Lactobacillus bulgaricus sp1.1. [ABSTRACT FROM AUTHOR]

Lactic acid has been proved to inhibit the proliferation of lactic acid bacteria in the fermentation process. To shed light on the cell cycle alterations in acidic conditions, the cell division of Lactobacillus bulgaricus sp1.1 in batch culture was analyzed directly by implementing of the intracellular fluorescent tracking assay in different pH adjusted by lactic acid. Cell proliferation and cell division were investigated to be negatively controlled by the decrease of pH, and pH 4.1 was the critical condition of downregulating cell division but retains cell culturability. The cell area and cell length in pH 4.1 were examined by using fluorescent labeling, and they reduced to about 29.18–34.89% and 32.67–40% of cells cultured in the unacidified medium, respectively. The DNA replication initiation was undergoing prompted by the low extent of DNA condensation and higher expression of the dnaA gene in this critical pH. The results indicated that the cell cycle progressions of Lactobacillus bulgaricus sp1.1 in acidic conditions were arrested at intracellular biomass accumulation and cell division stage. These findings provide fundamental insight into cell cycle control of the acidic environment in Lactobacillus bulgaricus sp1.1. [ABSTRACT FROM AUTHOR]

The G protein-coupled receptors (GPRs) have been shown to regulate several cancer related processes. The aberrant expression of GPRs has been linked to the development of several cancers. The present study was designed to examine the expression and decipher the role of GPR15 in the development of human colorectal cancer. The results revealed GPR15 to be significantly (P < 0.05) upregulated in colorectal cancer cells. The silencing of GPR15 inhibited the growth of the colorectal cancer cells via induction of apoptosis. Induction of apoptosis in colorectal cancer cells was associated increase in Bax and decrease in Bcl-2 expression. The silencing of GPR-15 also caused a significant (P < 0.05) decline in the migration and invasion of the colorectal cancer cells. Bioinformatic analysis and luciferase assay revealed that the expression of GPR15 to be post-transcriptionally regulated by microRNA-1225 (miR-1225). The expression of miR-1225 was found to significantly (P < 0.05) downregulated in colorectal cancer cells and its overexpression caused suppression of GPR15 and inhibited the proliferation of the colorectal cancer cells. Nonetheless, overexpression of GPR15 could avoid the growth inhibitory effects of miR-1225. The results suggest that the GPR15/miR-1225 axis play an important role in the development of colon rectal cancer and exhibit therapeutic implications for its treatment. [ABSTRACT FROM AUTHOR]

The effects of fructose on plantaricin Q7 biosynthesis in Lactobacillus plantarum (L. plantarum) Q7 were investigated. Fructose induced and accelerated plantaricin Q7 production in the early stages of biosynthesis. Two-dimensional electrophoresis and quantitative real-time reverse transcriptase PCR (qRT-PCR) revealed that shock-related proteins were overexpressed in L. plantarum grown in MRS-fructose compared with cultures grown in MRS broth. A preheat-shock (PHS) treatment was used to overexpress shock-related proteins to enhance plantaricin Q7 production. The final plantaricin Q7 level reached 2873.08 IU/mL following PHS treatment, which was 23.36% higher than that obtained using a control strategy without PHS treatment. qRT-PCR analyses indicated that only groL was induced (by 10-fold) following PHS treatment. Evidently, groL plays a critical role in plantaricin Q7 biosynthesis. These results demonstrate that PHS treatment is an efficient approach to improving plantaricin Q7 production. The information obtained in this study may increase the amount of efficient antimicrobial peptide production using L. plantarum. [ABSTRACT FROM AUTHOR]

The polyimide/montmorillonite nanocomposite based on the reactive montmorillonite with amino was prepared via in situ polymerization. The reactive montmorillonite with amino was obtained by the intercalation and coupling reaction. The reactive montmorillonite could be dispersed well in the polyimide and had good compatibility with polyimide. The reactive montmorillonite influenced the crystal structure and the molecular weight of the polyimide. Polyimide/montmorillonite nanocomposite based on the reactive montmorillonite had uniform weight distribution. The light transmittance of polyimide nanocomposite decreased compared to pure polyimide. Thermal stability and mechanical properties of polyimide/montmorillonite nanocomposite were improved by adding small amount of the reactive montmorillonite with the amino. In contrast to pure polyimide, the tensile strength of polyimide nanocomposite increased by 54.6%, and Young's modules increased to 2.02 from 1.56 GPa. Finally, the formation mechanism of the polyimide/montmorillonite nanocomposite based on the reactive montmorillonite with aminos was proposed. The approach of the preparation was also applied to other polymer nanocomposites. [ABSTRACT FROM AUTHOR]

The urea-formaldehyde resin/reactive montmorillonite composites were prepared by in situ polymerization. The reactive montmorillonite was prepared firstly by being ion exchanged with organic molecules and secondly by being grafted with silane coupling agent, which could be demonstrated by X-ray diffraction (XRD) and thermogravimetric analysis (TGA). Scanning electron microscopy (SEM) revealed that the morphology of the urea-formaldehyde resin/reactive montmorillonite composites were ellipsoid or columnar particles. Energy dispersive spectrometry (EDS) confirmed that the reactive montmorillonite was encapsulated by urea-formaldehyde resin. Differential scanning calorimetry (DSC) indicated that curing process of the urea-formaldehyde resin/reactive montmorillonite composites consumed more energy than pure urea-formaldehyde resin. Thermogravimetric analysis (TGA) showed that the thermal stability of the urea-formaldehyde resin/reactive montmorillonite composites improved compared to pure urea-formaldehyde resin. Furthermore, the reactive montmorillonites reduced the formaldehyde emission of the composites and increased the water resistance. Finally, the mechanism to prepare the urea-formaldehyde resin/reactive montmorillonite composites was proposed. [ABSTRACT FROM AUTHOR]

PMMA/reactive nanoclay nanocomposites were prepared by emulsion polymerization using two different reactive nanoclays. X-ray diffraction (XRD) and thermogravimetric analysis (TGA) results confirmed that the reactive nanoclays, kaolinite and montmorillonite, were obtained by the silylation reaction and the double bonds were grafted onto the edges and surfaces of the nanoclays. The presence of reactive nanoclays could increase the average molecular weights, the glass transition temperatures ( T ) and improve the thermal properties of nanocomposite. The tensile properties, Young's modulus, and the aging properties of the nanocomposite films were also enhanced while the light transmittance decreased. Furthermore, the nanocomposites with the reactive kaolinite presented better performances than that with the reactive montmorillonite. Finally, the action mechanism of the reactive nanoclays to the performances of PMMA/reactive nanoclay nanocomposites was proposed. [ABSTRACT FROM AUTHOR]

To reduce the content of MgOHCl in anhydrous MgCl, MgOHCl was converted to anhydrous MgCl by solid-state reaction. Factors that affect the conversion effects were investigated, including the mol ratio of NHCl to MgOHCl, thickness of covering agent, reaction temperature, and reaction time. The conversion process was characterized by XRD analysis and chemical analysis. The solid-state reaction mechanism was studied and discussed. The MgO content in anhydrous MgCl achieved 0.05 pct under the optimal conditions: the mol ratio of NHCl to MgOHCl was 3:1, thickness of AlO powder 2 cm, reaction temperature 623 K (350 °C), and reaction time 1 hour. [ABSTRACT FROM AUTHOR]

Current-induced magnetization reversal via spin-orbit torques (SOTs) has been intensively studied in heavy-metal/ferromagnetic-metal/oxide heterostructures due to its promising application in low-energy consumption logic and memory devices. Here, we systematically study the function of Joule heating and SOTs in the current-induced magnetization reversal using Pt/Co/SmOx and Pt/Co/AlOx structures with different perpendicular magnetic anisotropies (PMAs). The SOT-induced effective fields, anisotropy field, switching field and switching current density (Jc) are characterized using electric transport measurements based on the anomalous Hall effect and polar magneto-optical Kerr effect (MOKE). The results show that the current-generated Joule heating plays an assisted role in the reversal process by reducing switching field and enhancing SOT efficiency. The out-of-plane component of the damping-like-SOT effective field is responsible for the magnetization reversal. The obtained Jc for Pt/Co/SmOx and Pt/Co/AlOx structures with similar spin Hall angles and different PMAs remains roughly constant, revealing that the coherent switching model cannot fully explain the current-induced magnetization reversal. In contrast, by observing the domain wall nucleation and expansion using MOKE and comparing the damping-like-SOT effective field and switching field, we conclude that the current-induced magnetization reversal is dominated by the depinning model and Jc also immensely relies on the depinning field. [ABSTRACT FROM AUTHOR]

A letter to the editor concerning the article "Continuous Wound Infusion of Ropivacaine for the Control of Pain After Thoracolumbar Spinal Surgery: A Randomized Clinical Trial" published online in 2015 is presented.