Toward a Practical Zn Powder Anode: Ti3C2Tx MXene as a Lattice-Match Electrons/Ions Redistributor

The renaissance of aqueous Zn ion batteries has drawn intense attention to Zn metal anode issues, including dendrites growth, dead Zn, low efficiency, and other parasitic reactions. However, against the widely used 2D Zn foil, in fact, the Zn powder anode is a more practical choice for Zn-based batteries in industrial applications, but the related solutions are rarely investigated. Herein, we focus on the Zn powder anode and disclose its unknown failure mechanism different from Zn foils. By utilization of 2D flexible conductive Ti₃C₂Tx MXene flakes with hexagonal close-packed lattice as electrons and ions redistributor, a stable and highly reversible Zn powder anode without dendrite growth and low polarization is constructed. Low lattice mismatch (∼10%) enables a coherent heterogeneous interface between the (0002) plane of deposited Zn and (0002) plane of the Ti₃C₂Tx MXene. Thus, the Zn²⁺ ions are induced to undergo rapid uniform nucleation and sustained reversible stripping/plating with low energy barriers via the internally bridged shuttle channels. Paired with cyano group iron hexacyanoferrate (FeHCF) cathode, the FeHCF//MXene@Zn full battery delivers superior cycle durability and rate capability, whose service life with a CE of near 100% touches 850% of bare Zn powder counterparts. The proposed Ti₃C₂Tx MXene redistributor strategy concerning high-speed electrons/ions channel, low-barrier heterogeneous interface, is expected to be widely applied to other alkali metal anodes.

[Study on the feature of cortical auditory evoked potential under different auditory tasks in cochlear implant children]

Objective: To investigate the variation regularity and influencing factors of cortical auditory evoked potential (CAEP) evoked by pure tone, syllable and tone stimuli in cochlear implant (CI) children. Methods: Cortical auditory evoked potential (CAEP) responses were collected from 46 CI children in the sound field. Pure tones with frequencies of 1 kHz and 2 kHz were used as the standard and the deviant respectively in the pure tone stimulation condition. The Chinese Mandarin tokens/ba/-/pa/and/ba1/-/ba4/pairs were used as the stimuli respectively in the syllable and tone stimulation condition. The latency, amplitude and presence rate of P1 and mismatch negative(MMN) were obtained and the correlation between the difficulty of auditory task, the age of hearing month, the duration of severe-profound hearing loss, the wearing history of hearing aid before CI, the hearing threshold of the better ear before CI and the latency and amplitude of P1 and MMN were analyzed. All statistical analyses and figures were conducted using SPSS 25.0. Results: The P1 presence rate of pure tone, syllable and tone group was 100% (17/17), 100% (13/13) and 75.0% (12/16), respectively, with significant difference (χ²=8.214, P=0.016). There was significant difference between pure tone group and tone group (χ²=4.836, P=0.028), but no significant difference between pure tone group and syllable group, syllable group and tone group. The MMN presence rate of pure tone, syllable and tone group was 94.1% (16/17), 84.6% (11/13) and 62.5% (10/16), respectively, but no significant difference among the three groups with different auditory tasks(χ²=0.066, P=0.066). No significant difference was observed among the three groups of different auditory tasks in the latency and amplitude of P1 and MMN. Multiple linear regression analysis showed that the latency of P1 was positively correlated with the difficulty of auditory task and the hearing threshold of the better ear before CI, and negatively correlated with hearing age and the history of hearing aid before CI. The latency of MMN was positively correlated with the difficulty of auditory task, and negatively correlated with hearing age. Conclusions: The P1 presence rate of pure tone auditory task is significantly higher than that of tone auditory task. The difficulty of auditory task, hearing age, the history of hearing aid before CI, and the hearing threshold of the better ear before CI has significant effects on the P1 latency. The difficulty of auditory task and hearing age has significant effects on the MMN latency.

A cross-sectional survey of preschool children: Exploring heavy metal exposure, neurotransmitters, and neurobehavioural relationships and mediation effects

BACKGROUND

Exposure to heavy metals has been considered harmful and can cause cognitive deficits in preschool children.

OBJECTIVE

To investigate the possible mediation effect of neurotransmitters on the relationship of heavy metal exposure with neurobehaviour.

METHODS

The levels of blood heavy metals and neurotransmitters, along with the neurobehavioural scores, were determined in preschool children. Multiple linear regression was used to assess the relationship between heavy metals, neurotransmitters, and neurobehavioural scores. Furthermore, the mediating role of neurotransmitters was investigated.

RESULTS

An interquartile range (IQR) increase in lead (6.10 μg/L) was associated with a decrease of 8.52%, 30.06%, and 20.10% for Glutamic acid (Glu), Glycine (Gly), and gamma-aminobutyric acid (GABA), respectively. An IQR increase in arsenic (19.37 μg/L) was associated with an increase of 6.32% and 2.09% for Gly and GABA, respectively. Further, an IQR increase in zinc (15.58 μg/L) was associated with an increase of 1.44% for Ser, whereas the IQR increase was associated with a decrease of 2.14%, 2.24%, and 1.89% for Glu, Gly, and GABA, respectively. An IQR increase in selenium (38.75 μg/L) was associated with an increase of 1.88% for GABA. Moreover, both Glu and Gly decreased by 2.87% for an IQR increase in manganese (16.92 μg/L). An IQR increase in mercury (15.22 μg/L) was associated with a decrease of 2.43% for Ser, but the IQR increase was associated with an increase of 4.99% and 3.09% for Gly and GABA, respectively. It was found that Glu and Serine (Ser) have a significant linear relationship with conduct score and impulsivity-hyperactivity index, and that there was a significant linear relationship between Ser and the learning disability index. GABA and conduct score and attention-deficit hyperactivity disorder (ADHD) index have a significant linear relationship. There is a significant linear relationship between Gly and conduct, anxiety, ADHD, and impulsivity-hyperactivity index. The results of the mediating effect analysis indicated that Ser, Glu, Gly, and GABA have a specific mediating effect between blood heavy metals and neurobehaviour.

CONCLUSION

We showed the mediating effect of neurotransmitters. The current study may provide valuable information regarding the prevention and management of metal-related neurological disorders in preschool children.

Efficacy and Safety of Astragalus-Containing Traditional Chinese Medicine Combined With Platinum-Based Chemotherapy in Advanced Gastric Cancer: A Systematic Review and Meta-Analysis

Background

Astragalus-containing traditional Chinese medicine (TCM) is widely used as adjunctive treatment to platinum-based chemotherapy (PBC) in patients with advanced gastric cancer (AGC) in China. However, evidence regarding its efficacy remains limited. This study aimed to evaluate the efficacy and safety of Astragalus-containing TCM combined with PBC in AGC treatment.

Methods

We searched for literature (up to July 19, 2020) in eight electronic databases. The included studies were reviewed by two researchers. The main outcomes were the objective response rate (ORR), disease control rate (DCR), survival rate, quality of life (QOL), adverse drug reactions (ADRs), and peripheral blood lymphocyte levels. The effect estimate of interest was the risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CIs). Trial sequential analysis (TSA) was used to detect the robustness of the primary outcome and to calculate the required information size (RIS). Certainty of the evidence was assessed using the GRADE profiler.

Results

Results based on available literature showed that, compared with patients treated with PBC alone, those treated with Astragalus-containing TCM had a better ORR (RR: 1.24, 95% CI: 1.15–1.34, P < 0.00001), DCR (RR: 1.10, 95% CI: 1.06–1.14, P < 0.00001), 1-year survival rate (RR: 1.41, 95% CI: 1.09–1.82, P = 0.009), 2-year survival rate (RR: 3.13, 95% CI: 1.80–5.46, P < 0.0001), and QOL (RR: 2.03, 95% CI: 1.70–2.43, P < 0.00001 and MD: 12.39, 95% CI: 5.48–19.30, P = 0.0004); higher proportions of CD3⁺ T cells and CD3⁺ CD4⁺ T cells; higher ratio of CD4⁺/CD8⁺ T cells; nature killer cells; and lower incidence of ADRs. Subgroup analysis showed that both oral and injection administration of Astragalus-containing TCM increased tumor response. Whether treatment duration was ≥8 weeks or <8 weeks, Astragalus-containing TCM could increase tumor response in AGC patients. Furthermore, Astragalus-containing TCM combined with oxaliplatin-based chemotherapy could increase the ORR and DCR; when with cisplatin, it could only increase the ORR.

Conclusion

Current low to moderate evidence revealed that Astragalus-containing TCM combined with PBC had better efficacy and less side effects in the treatment of AGC; however, more high-quality randomized studies are warranted.

Systematic Review Registration

PROSPERO, identifier CRD42020203486.

P–368 Dynamic metabolomic profiling during early implantation period

Study question

To investigate the different metabolomic profiling in serum between pregnant and non-pregnant women during early implantation period.

Summary answer

Metabolomics of progesterone-related hormones enhances from ET day3 for pregnancy women compared with non-pregnancy women.

What is known already

Metabolomics is based on high-throughput analytical methods to identify and quantify metabolites. Compared to other omics study, metabolomics is the closest one to the phenotype, allowing the observation of dynamic changes in phenotype at specific timepoints. So far there is no published work about the metabolomics profile in human early implantation period. Study design, size, duration: Study design: comparative study. Size: 14 pregnancy women and 14 non-pregnancy women. duration: time-course.

Participants/materials, setting, methods

Participants: pregnancy women and unpregnancy women after embryo transfer (ET). Setting: university-based study. Methods: Peripheral blood were collected at ET day0, 3, 6 and 9. metabolomic profiling in serum by platforms of capillary electrophoresis-mass spectrometry (CE-MS) and liquid chromatography–mass spectrometry (LC-MS).

Main results and the role of chance

There were no statistical difference of the age, BMI, basal FSH level, endometrium thickness on the day of embryo transfer, distribution of primary and secondary fertility, embryo transfer cycle as well as the infertile types between the two groups. After deleting those with over 50% missing data, we finally have 310 metabolites into statistical analysis. Among the 310 metabolite, lipid metabolites account the largest percentage, nearly half of all metabolites. The second biggest class of metabolites in our data was organic acids. Combined results in repeated measurement ANOVA (RM-ANOVA) and ANOVA-simultaneous component analysis (ASCA) as well as multivariate empirical Bayes time-series analysis (MEBA), we finally found that progesterone-related hormones were the most important metabolites for the whole time-series data. Those significant metabolites showed a significant down regulation from ET day0 to ET day3 and up regulation from ET day3 to ET day9.

Limitations, reasons for caution

we have limited sample size for this study and further validation is necessary for confirmation.

Wider implications of the findings: The phenomenon of upregulation of progesterone-related hormones from day3 in pregnancy group might be related to the embryo-originated hcg. Because the embryo has entered into endometrium at day3 and produced cytokines, hcg and other interaction with endometrium.

Trial registration number

NA

The complete chloroplast genome of Agrostis capillaris L

Agrostis capillaris is a cool-season turf grass species that is found worldwide in temperate countries, and a good Pb phytostabilizer. In this study, the entire chloroplast genome sequence of A. capillaris was determined by Illumina sequencing. The complete chloroplast genome was circular and composed of 136,396 bp nucleotides with a GC content of about 38.5%. There were a large single-copy region (LSC, 81,659bp), a small single-copy region (SSC, 12,593bp), and a pair of reverse repeat regions (IRs, 42,144bp) in the chloroplast genome. In total, the A. capillaris chloroplast genome contained 144 genes, including 96 protein-coding genes, 40 tRNA genes, and 8 rRNA genes. Phylogenetic analysis revealed that A. capillaris was closely related to A. gigantean. The sequence data of A. capillaris chloroplast genome could provide useful genetic information for the studies on phylogenetic and evolutionary of Agrostidinae.

Leptin attenuates hypoxia-induced apoptosis in human periodontal ligament cells via the reactive oxygen species-hypoxia-inducible factor-1α pathway

NEW FINDINGS

What is the central question of this study? Does leptin have an effect on hypoxia-induced apoptosis in human periodontal ligament cells (hPDLCs), and what is the potential underlying mechanism? What is the main finding and its importance? Hypoxia induces cell apoptosis and leptin expression in hPDLCs through the induction of hypoxia-inducible factor-1α and accumulation of reactive oxygen species (ROS). Leptin shows feedback inhibition on hypoxia-induced ROS-mediated apoptosis in hPDLCs, suggesting a new application of leptin for hypoxic damage in periodontal diseases.

ABSTRACT

Hypoxia-induced apoptosis of human periodontal ligament cells (hPDLCs) is an important contributor to the progression of various periodontal diseases. Although leptin has been shown to protect connective tissue cells against hypoxia-induced injury, whether it might do so by attenuating hypoxia-induced apoptosis in hPDLCs remains unclear. Here, using CoCl₂ treatment, we simulated hypoxic conditions in hPDLCs and explored whether apoptosis and reactive oxygen species (ROS) levels were related to hypoxia. After small interfering RNA (siRNA) inhibition of leptin and hypoxia-inducible factor-1α (HIF-1α), the levels of apoptosis, ROS and leptin expression were measured. We showed that in CoCl₂ -treated hPDLCs, significantly higher cell apoptosis rates and ROS accumulation were observed. Cobalt chloride also increased leptin and HIF-1α expression in hPDLCs. Further investigation of the pathway demonstrated that inhibition of ROS attenuated hypoxia-induced cell apoptosis and leptin expression, whereas siRNA inhibition of leptin aggravated hypoxia-induced cell apoptosis and ROS accumulation. Hypoxia induces cell apoptosis and leptin expression in hPDLCs through the induction of ROS and HIF-1α pathways, and leptin shows feedback inhibition on ROS-mediated apoptosis in hPDLCs. These findings suggest a new application of leptin for hypoxic damage in periodontal diseases.

Exosomes in the lung cancer microenvironment: biological functions and potential use as clinical biomarkers

Lung cancer is one of the most common malignant tumours worldwide. however, emerging immunotherapy and targeted therapies continue to show limited efficacy. In the search for new targets for lung cancer treatment, exosomes have become a major focus of research. Exosomes play an important role in the tumour microenvironment (TME) of lung cancer and affect invasion, metastasis, and treatment responses. This review describes our current understanding of the release of exosomes derived from different cells in the TME, the effects of exosomes on T/Tregs, myeloid-derived suppressor cells, tumour-associated macrophages, dendritic cells, and natural killer cells, and the role of exosomes in the endothelial–mesenchymal transition, angiogenesis, and cancer-associated fibroblasts. In particular, this review focuses on the potential clinical applications of exosomes in the lung cancer microenvironment and their prognostic and diagnostic value.

Multiple antibiotics distribution in drinking water and their co-adsorption behaviors by different size fractions of natural particles

In recent years, natural particles in drinking water have attracted attention due to their carry of toxic organic matter. However, the adsorption behavior of multiple antibiotics at very low concentrations on different sized particles has not been revealed. Here, the content of 17 antibiotics in water samples collected from four process stages of the water supply plant was detected. Results showed the concentration of antibiotics in water plant was in the range of 0-69.24 ng L^-1. Characterization of natural particles obtained directly from raw water of waterworks showed that the surface of large particles (>1 μm) was rougher and the composition was more complex than that of small particles (0.05-1 μm). Besides, the adsorption experiments of four antibiotics (nalidixic acid (NAL), trimethoprim (TMP), roxithromycin (ROX), and penicillin G potassium salt (PG)) on small (0.05-1 μm) and large (>1 μm) natural particles were studied. The results indicated that in the binary antibiotic system, the competition and synergy between antibiotics made a greater proportion of antibiotics soluble in water comparing with single systems, and the particle-water partition coefficient (k_p-w) of the total antibiotics ranged from 1.13-1.78 was reduced to 0.57-0.84. The competitive adsorption of antibiotics appeared in the binary system showed that ROX and PG had a higher adsorption capacity than NAL and TMP. Furthermore, in the binary antibiotic systems, small particles played an important role in adsorption, suggesting the urgency of their removing. This work could help predict the possible risks of drinking water and provide some insights into future drinking water treatment.

The effects of short time hyperoxia on glutamate concentration and glutamate transporters expressions in brain of neonatal rats

Preterm infants often suffer from impaired postnatal brain development, and glutamate excitotoxicity is identified as a pivotal mechanism of hyperoxia-induced neurological abnormality. We aimed to investigate the effect of short time hyperoxia on glutamate homeostasis and glutamate transporters expressions in immature brain. Six-day-old (P6) rat pups were exposed to 80% oxygen for 24 h (the hyperoxia group) or placed in atmospheric air (the control group). The concentrations of glutamate and γ-aminobutyric acid (GABA) in immature cerebrum and cerebellum at P7, P14 and P21 were determined by ELISA. The mRNA levels of glutamate transporters including excitatory amino acid transporter 1 (EAAT1), EAAT2, EAAT3, vesicular glutamate transporter 1 (VGLUT1) and VGLUT2 in brain were determined by qPCR. Glutamate accumulation was induced by hyperoxia both in immature cerebrum and cerebellum at P7 but got gradually attenuated at P14 and P21, as evidenced by the changes of glutamate and GABA concentrations. Hyperoxia also induced sustained glutamatic oxidative stress in both cerebrum and cerebellum, as GSH (reduced glutathione) levels in the hyperoxia group were constantly higher than the control group at three examined time-points. Furthermore, at P7, the expressions of all glutamate transporters decreased in both cerebrum and cerebellum except that of EAAT1. At P21, VGLUT2 in cerebrum and EAAT1, EAAT3 and VGLUT2 in cerebellum still displayed significant decrease in expression levels upon hyperoxia stimulation. Taken together, our results indicate that hyperoxia induces glutamate accumulation in brain of rat pups, which is associated with increased oxidative stress and decreased expressions of glutamate transporters.

A Self-Healing Crease-Free Supramolecular All-Polymer Supercapacitor

While traditional three-layer structure supercapacitors are under mechanical manipulations, the high-stress region concentrates, inevitably causing persistent structural problems including interlayer slippage, crease formation, and delamination of the electrode-electrolyte interface. Toward this, an all-polymeric, all-elastic and non-laminated supercapacitor with high mechanical reliability and excellent electrochemical performance is developed. Specifically, a polypyrrole electrode layer is in situ integrated into a silk fibroin-based elastic supramolecular hydrogel film with extensive hydrogen and covalent bonds, where a non-laminate device is realized with structural elasticity at the device level. The non-laminate configuration can avoid slippage and delamination, while the elasticity can preclude crease formation. Furthermore, under more severe mechanical damage, the supercapacitors can restore the electrochemical performance through non-autonomous self-healing capabilities, where the supramolecular design of host-guest interactions in the hydrogel matrix results in a superior self-healing efficiency approaching ≈95.8% even after 30 cutting/healing cycles. The all-elastic supercapacitor delivers an areal capacitance of 0.37 F cm-2 and a volumetric energy density of 0.082 mW h cm-3, which can well-maintain the specific capacitance even at -20 °C with over 85.2% retention after five cut/healing cycles.

Orbital-angular-momentum-resolved diagnostics for tracking internal phase evolution in multi-bound solitons

The generation of multi-bound solitons is a fascinating subject of investigation in many conservative and dissipative systems, such as photonics, fluid mechanics, Bose-Einstein condensates, and so on. In this study, we demonstrate the successful extraction of phase dynamics between solitons in bound multiple solitons with up to seven constituents in a mode-locked Er laser system. By mapping the internal phase motions of multi-bound solitons to the spatial phase movement of cylindrical vector beams using orbital angular momentum (OAM)-based diagnostics, different categories of internal pulsations are revealed. We show that bound state of four solitons exhibits linear drifting relative phase evolution dynamics; while for bound multiple solitons with constituents from five to seven pulses, stationary relative phase dynamics are observed. These findings highlight the possibility of the OAM-based method access to the internal motion of multi-soliton molecules with more freedom of degrees and fuel the analogy with research on chemistry molecule complex.

The effect of targeted nursing on the quality of sleep and life in lung cancer patients undergoing chemotherapy

OBJECTIVE

To explore the effect of targeted nursing on the quality of sleep and life in lung cancer patients undergoing chemotherapy.

METHODS

This study was conducted in 88 lung cancer patients who underwent chemotherapy. According to the random number table, these patients were assigned to the control group (n=44) and the experimental group (n=44). In the control group, patients received routine nursing. Meanwhile, patients in the experimental group received both routine nursing and targeted nursing. The quality of sleep score, quality of life score, psychological state-related score, and visual analogue scale (VAS) score on admission and 1 week after discharge were compared between the two groups.

RESULTS

There were no differences in the quality of sleep score, quality of life score, psychological state-related score, and VAS score between the two groups of patients on admission (all P>0.05). Compared with those on admission, the quality of sleep score, quality of life score, psychological state-related score, and VAS score in both groups 1 week after discharge were declined (all P<0.05). Additionally, the changes in the experimental group were much bigger than those in the control group (all P<0.001). Satisfaction in nursing in the experimental group was higher than that in the control group (P<0.05).

CONCLUSION

Targeted nursing can improve the quality of sleep, quality of life, psychological state, and satisfaction in nursing in lung cancer patients undergoing chemotherapy.

Electrogeneration of H2O2 utilizing anodic O2 on polytetrafluoroethylene-modified cathode in flow-through reactor

Efficient electrogeneration of hydrogen peroxide (H₂O₂) is critical for treatment of refractory pollutants by the electro-Fenton process. An effective strategy is developed by combining a flow-through reactor with a poly- tetrafluoroethylene (PTFE)-modified graphite felt cathode. In this design, anodic oxygen is directly used for efficient H₂O₂ generation at the modified cathode. Experimental results show that the modified cathode with the optimum PTFE content can produce 29.6 mg/L of H₂O₂, which is 16 times higher than the unmodified graphite felt cathode for a flow rate of 3 mL/min. Maximum H₂O₂ production, up to 30.7 mg/L, was obtained under the following conditions: 120 mA, 3 mL/min, initial pH 13, no external aeration.

The complete chloroplast genome of Securigera varia (L.) Lassen

Securigera varia is an important leguminous forage grass species that is mainly distributed in arid and semi-arid land with water scarcity, and has outstanding drought resistance. In this study, Illumina sequencing was used to obtain the complete sequence of the S. varia chloroplast genome. The complete genome was 154,257 bp in length with 35.9% GC content. It was a circular genome containing a large single-copy region (LSC, 84,762 bp), a small single-copy region (SSC, 18,059 bp), and a pair of inverted repeat regions (IRs, 51,436 bp). A total of 128 genes were encoded, including 83 protein-coding genes, 37 tRNAs, and 8 rRNAs. Phylogenetic analysis revealed that S. varia was closely related to Robinia pseudoacacia. The sequence data of S. varia chloroplast genome could provide useful genetic information for the studies on phylogenetic and evolutionary of Leguminosae.

Inhibition of HMGB1 reduced high glucose-induced BMSCs apoptosis via activation of AMPK and regulation of mitochondrial functions

High mobility group box-1 (HMGB1) participates actively in oxidative stress damage, and the latter relates closely to diabetes and diabetic complications including osteoporosis, though the underlying mechanisms are elusive. This study aimed to investigate the effect of high glucose on bone marrow stromal cells (BMSCs) apoptosis and the role of HMGB1 in this process. BMSCs were isolated from 2-week-old Sprague-Dawley rats and cultured in medium containing normal glucose (NG), high glucose (HG), high glucose + glycyrrhizin (HMGB1 inhibitor, HG+GL), and high glucose + glycyrrhizin + dorsomorphin (AMPK inhibitor, HG+GL+Dm), respectively. Cell apoptosis, expression of HMGB1, AMPK, apoptotic markers, and mitochondrial functions were detected. By these approaches, we demonstrated that HG treatment significantly upregulated the expression of HMGB1 in BMSCs, which could be attenuated by GL treatment. Inhibiting HMGB1 by GL improved AMPK activation, decreased mitochondrial ROS levels, increased mitochondrial membrane potential, normalized mitochondrial fission/fusion balance, and consequently reduced apoptosis of BMSCs under HG condition. The addition of AMPK inhibitor dorsomorphin hampered this protective effect. Taken together, our data show that inhibition of HMGB1 can be an effective approach to alleviate HG-induced BMSCs apoptosis by activation of AMPK pathway and relieving mitochondrial dysfunction.

Mitigation of soil salinization and alkalization by bacterium-induced inhibition of evaporation and salt crystallization

Soil salinization and alkalization is one of the most devastating environmental problems, threatening the sustainable development of agriculture. Bio-amelioration using microorganisms such as bacteria is a promising method for the remediation of calcareous sodic and saline-sodic soil due to its high efficiency, low cost and environmental-friendly characteristics. In the present study, a salt resistant bacterium, Bacillus subtilis BSN-1, was isolated from arid region in Xinjiang, China, and its effects on salt crystallization during evaporation crystallization of saline-alkali soil solution were examined. It was found that the fermentation products of B. subtilis BSN-1, such as glutamic acid, significantly lowered the pH of saline soil solution because of the ionization of carboxyl. The complexation between Ca²⁺ and fermentation products inhibited the precipitation of Ca-P compounds as well, since the binding sites supplied for Ca²⁺ is one or two orders of magnitude than that for HPO₄^2-. Moreover, the increased content of active phosphate is attributed to the chelation and adsorption exerted through carboxyl and amide bonds. These findings demonstrated that Bacillus subtilis BSN-1 suppressed the crystallization of phosphate and therefor increased the content of active phosphate, which may provide a promising solution for amendment and remediation of saline-alkali soil.

Exogenous melatonin improves growth in hulless barley seedlings under cold stress by influencing the expression rhythms of circadian clock genes

Background

Melatonin is a hormone substance that exists in various living organisms. Since it was discovered in the pineal gland of cattle in 1956, the function of melatonin in animals has been roughly clarified. Nevertheless, in plants, the research on melatonin is still insufficient. Hulless barley (Hordeum vulgare L. var. nudum hook. f.) is a crop that originates from cultivated barley in the east, usually grown on the Qinghai-Tibet Plateau, becoming the most important food crop in this area. Although the genome and transcriptome research of highland barley has gradually increased recently years, there are still many problems about how hulless barley adapts to the cold climate of the Qinghai-Tibet Plateau.

Methods

In this study, we set three temperature conditions 25°C, 15°C, 5°C hulless barley seedlings, and at the same time soaked the hulless barley seeds with a 1 µM melatonin solution for 12 hours before the hulless barley seeds germinated. Afterwards, the growth and physiological indicators of hulless barley seedlings under different treatment conditions were determined. Meanwhile, the qRT-PCR method was used to determine the transcription level of the hulless barley circadian clock genes under different treatment conditions under continuous light conditions.

Results

The results showed the possible mechanism by which melatonin pretreatment can promote the growth of hulless barley under cold stress conditions by studying the effect of melatonin on the rhythm of the circadian clock system and some physiological indicators. The results revealed that the application of 1 µM melatonin could alleviate the growth inhibition of hulless barley seedlings caused by cold stress. In addition, exogenous melatonin could also restore the circadian rhythmic oscillation of circadian clock genes, such as HvCCA1 and HvTOC1, whose circadian rhythmic phenotypes were lost due to environmental cold stress. Additionally, the results confirmed that exogenous melatonin even reduced the accumulation of key physiological indicators under cold stress, including malondialdehyde and soluble sugars.

Discussion

Overall, these findings revealed an important mechanism that exogenous melatonin alleviated the inhibition of plant vegetative growths either by restoring the disrupted circadian rhythmic expression oscillations of clock genes, or by regulating the accumulation profiles of pivotal physiological indicators under cold stress.

Enhanced Redox Kinetics and Duration of Aqueous I2 /I- Conversion Chemistry by MXene Confinement

Weak binding and affinity between the conductive support and iodine species leads to inadequate electron transfer and the shuttle effect. Herein, redox kinetics and duration are significantly boosted by introducing a Nb₂ CT_X host that is classified as a layered 2D Nb-based MXene. With a facile electrodeposition strategy, initial I^- ions are electrically driven to insert in the nanosized interlayers and are electro-oxidized in situ. Linear I₂ is firmly confined inside and benefits from the rapid charge supply from the MXene. Consequently, an aqueous Zn battery based on a Zn metal anode and ZnSO₄ electrolyte delivers an ultraflat plateau at 1.3 V, which contributes to 84.5% of the capacity and 89.1% of the energy density. Record rate capability (143 mAh g^-1 at 18 A g^-1 ) and lifespan (23 000) cycles are achieved, which are far superior to those of all reported aqueous MXenes and I₂ -metal batteries. Moreover, the low voltage decay rate of 5.6 mV h^-1 indicates its superior anti-self-discharge properties. Physicochemical analyses and density functional theory calculations elucidate that the localized electron transfer and trapping effect of the Nb₂ CT_X MXene host are responsible for enhanced kinetics and suppressed shuttle behavior. This work can be extended to the fabrication of other I₂ -metal batteries with long-life-time expectations.

Confining Aqueous Zn-Br Halide Redox Chemistry by Ti3C2TX MXene

With fluidity and dangerous corrosiveness, liquid insulating bromine elemental (Br₂) can hardly be confined by traditional conductive carriers (mainly carbon materials) for efficient redox without shuttle behavior. Thus, stationary Br₂-based energy storage devices are rarely advanced. Here, we introduce an electrochemical active parasite Br₂ to the Ti₃C₂T_XMXene host and construct an advanced aqueous zinc redox battery via a facile electrodeposition process (Br-Ti₃C₂T_X). Both ex situ experimental characterizations and density functional theory (DFT) simulations have validated the natural affinity between MXenes and Br species, which is manifested as their spontaneous fixation accompanied by rapid transfer of electrons in the interface region and interlayer confinement. Consequently, the battery delivers a high-voltage plateau at 1.75 V that contributes to an improved energy density of 259 Wh kg^-1_Br (144 Wh kg^-1_Br-Ti3C2TX), exhibiting efficient output capability in the high-voltage region. Besides, benefiting from enhanced redox kinetics, the capacity achieved at -15 °C approaches to 69% of the value at room temperature. More importantly, an excellent 10 000 cycles at -15 °C with negligible capacity decay is identified. The paradigm represents a step forward for developing stationary aqueous metal-Br₂ batteries.

Asphyxia and Neonatal Respiratory Distress Syndrome Are Independent Predictors of the Non-response to Inhaled Nitric Oxide in the Newborns With PPHN

Aim: Not all the neonates respond with improvement in oxygenation following inhaled nitric oxide treatment (iNO) treatment. The aim of this study was to assess the independent risk factors associated with non-response to iNO during the 2 weeks of postnatal treatment in neonates diagnosed with persistent pulmonary hypertension (PPHN). Materials and Methods: This retrospective cohort study included all newborns with PPHN who received iNO treatment for more than 24 h. Demographic, obstetric, perinatal data and clinical complications were extracted from the hospitalization records. Subjects were divided into two groups according to their response to iNO inspiration during the first 24 h of iNO treatment. No response was defined as an increase in SpO₂ < 5% or the inability to sustain saturation levels in the first 24 h of iNO treatment. For descriptive statistics, χ² and t-test analysis were used to compare categorical and continuous variables between the two groups. To evaluate independent risk factors of non-responsiveness to iNO treatment, binary logistic regression analysis were performed. Results: A total of 75 newborns were included in the study. Sixty-two cases were in the responders group, and 13 cases were in the non-responders group. Univariate analysis showed that asphyxia, neonatal respiratory distress syndrome (NRDS), pulmonary surfactant administration, meconium aspiration syndrome (MAS), the severity of pulmonary hypertension (PH), and high-frequency oscillatory ventilation (HFOV) therapy were the high-risk factors affecting the response to iNO treatment in the newborns with PPHN. The binary logistic regression analysis indicated that asphyxia and NRDS incidence were independent predictors of non-responsiveness to iNO treatment [asphyxia: OR 4.193, 95% CI 1.104-15.927, P = 0.035; NRDS: OR 0.154, 95% CI 0.036-0.647, P = 0.011]. The patients in the non-responders group had shorter iNO inspiration followed by MV duration, supplemental oxygen and hospital stay, and higher mortality. There were no significant differences in IVH, PVL, and BPD between two groups. Conclusion: In the newborns with PPHN, asphyxia and NRDS resulted as the independent risk factors of non-responsiveness to iNO therapy. Asphyxia in the newborns with PPHN is detrimental to the response to iNO treatment, while NRDS is beneficial.

Microglia Play an Essential Role in Synapse Development and Neuron Maturation in Tissue-Engineered Neural Tissues

In the process of constructing engineered neural tissues, we often use mixed primary neural cells, which contain microglia in the cell culture. However, the role that microglia play in the construction of engineered neural tissue has not been well studied. Here, we generated three-dimensional (3D) engineered neural tissues by silk fibroin/collagen composite scaffolds and primary mixed cortical cells. We depleted microglial cells by magnetic separation. Then, we analyzed the neural growth, development, mature and synapse-related gene, and protein expressions compared with the control engineered neural tissues with the microglia-depleted engineered neural tissues. We found that the engineered neural tissues constructed by magnetic separation to remove microglia showed a decrease in the number of synaptic proteins and mature neurons. These findings link microglia to neuron and synaptic maturation and suggest the importance of microglia in constructing engineered neural tissues in vitro.