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Since the Cenozoic, the Tibetan Plateau has experienced large‐scale uplift and outgrowth due to the India–Asia collision. However, the mechanism and timing of these tectonic processes still remain debated. Here, using apatite fission track dating and inverse thermal modeling, we explore the mechanism of different phases of rapid cooling for different batholiths and intrusions in the southeastern Tibetan Plateau. In contrast to previous views, we find that the coeval granitic batholith exposed in the same tectonic zone experienced differential fast uplift in different sites, indicating that the present Tibetan Plateau was the result of differential uplift rather than the entire lithosphere uplift related to lithospheric collapse during Cenozoic times. In addition, we also suggest that the 5–2 Ma mantle‐related magmatism should be regarded as the critical trigger for the widely coeval cooling event in the southeastern Tibetan Plateau, because it led to the increase in atmospheric CO2 level and a hotter upper crust than before, which are efficient for suddenly fast rock weathering and erosion. Finally, we propose that the current landform of the southeastern Tibetan Plateau was the combined influences of tectonic and climate. [ABSTRACT FROM AUTHOR]

Chemical manufacturing utilizing renewable sources and energy emerges as a promising path towards sustainability and carbon neutrality. The electrocatalytic reactions involving nitrogen oxides (NOx) offered a potential strategy for synthesizing various nitrogenous chemicals. However, it is currently hindered by low selectivity/efficiency and limited reaction pathways, mainly due to the difficulties in controllable generation and utilization of nitrogenous intermediates. In this minireview, focusing on nitrogenous intermediates in NOx‐involved electrocatalytic reactions, we discuss newly developed methodologies for studying and controlling the generation, conversion, and utilizing of nitrogenous intermediates, which enable recent developments in NOx‐involved electrocatalytic reactions that yield various products, including ammonia (NH3), organonitrogen molecules, and nitrogenous compounds exhibiting unconventional oxidation states. Furthermore, we also make an outlook to highlight future directions in the emerging field of NOx‐involved electrocatalytic reactions. [ABSTRACT FROM AUTHOR]

Chemical manufacturing utilizing renewable sources and energy emerges as a promising path towards sustainability and carbon neutrality. The electrocatalytic reactions involving nitrogen oxides (NOx) offered a potential strategy for synthesizing various nitrogenous chemicals. However, it is currently hindered by low selectivity/efficiency and limited reaction pathways, mainly due to the difficulties in controllable generation and utilization of nitrogenous intermediates. In this minireview, focusing on nitrogenous intermediates in NOx‐involved electrocatalytic reactions, we discuss newly developed methodologies for studying and controlling the generation, conversion, and utilizing of nitrogenous intermediates, which enable recent developments in NOx‐involved electrocatalytic reactions that yield various products, including ammonia (NH3), organonitrogen molecules, and nitrogenous compounds exhibiting unconventional oxidation states. Furthermore, we also make an outlook to highlight future directions in the emerging field of NOx‐involved electrocatalytic reactions. [ABSTRACT FROM AUTHOR]

In this work, a set of CuFe 1-x Y x O 2 (x = 0–0.02) specimens were synthesized using the conventional high-temperature solid-state reaction method, and the impact of Y3+ doping on the microstructure and magnetic properties of CuFeO 2 ceramics was investigated. The introduction of Y3+ ions in place of Fe3+ ions induced alterations in the microstructure of CuFeO 2 , leading to lattice distortion. X-ray diffraction analysis confirmed the presence of impurity phases in the CuFe 1-x Y x O 2 series samples at high doping concentrations (x ≥ 0.015). In contrast, low doping concentrations (x ≤ 0.0125) exhibited a singular copper-iron ore structure. The microstructures of the ceramic samples were examined using SEM, findings suggest that the presence of high concentrations of dopants hinders the formation of ceramic samples with high density. XPS analysis reveals that the introduction of a low concentration of Y3+ dopant does not impact the oxidation state of Cu and Fe. Raman spectroscopy results indicate that the doping process weakens the vibration mode of CuFe 1-x Y x O 2 ceramic samples. Additionally, measurements conducted using the PPMS demonstrate that the serial samples undergo two consecutive magnetic phase transitions at temperatures of 16K and 11K. The magnetization versus M − H curve of the doped sample exhibits both antiferromagnetic and ferromagnetic behavior. The increase in magnetic susceptibility can be attributed to the greater magnetic moment of doped Y3+ compared to Fe3+. Consequently, the magnetic transformation of the sample is influenced by various factors, including lattice distortion, alterations in ion valence states, variations in microscopic defect types, and modifications in magnetic interactions. [ABSTRACT FROM AUTHOR]

Fusarium verticillioides is one of the most important fungal pathogens causing maize ear and stalk rots, thereby undermining global food security. Infected seeds are usually unhealthy for consumption due to contamination with fumonisin B1 (FB1) mycotoxin produced by the fungus as a virulence factor. Unveiling the molecular factors that determine fungal development and pathogenesis will help in the control and management of the diseases. Kex2 is a kexin-like Golgi-resident proprotein convertase that is involved in the activation of some important proproteins. Herein, we identified and functionally characterized FvKex2 in relation to F. verticillioides development and virulence by bioinformatics and functional genomics approaches. We found that FvKex2 is required for the fungal normal vegetative growth, because the growth of the ∆Fvkex2 mutant was significantly reduced on culture media compared to the wild-type and complemented strains. The mutant also produced very few conidia with morphologically abnormal shapes when compared with those from the wild type. However, the kexin-like protein was dispensable for the male role in sexual reproduction in F. verticillioides. In contrast, pathogenicity was nearly abolished on wounded maize stalks and sugarcane leaves in the absence of FvKEX2 gene, suggesting an essential role of Fvkex2 in the virulence of F. verticillioides. Furthermore, high-performance liquid chromatography analysis revealed that the ∆Fvkex2 mutant produced a significantly lower level of FB1 mycotoxin compared to the wild-type and complemented strains, consistent with the loss of virulence observed in the mutant. Taken together, our results indicate that FvKex2 is critical for vegetative growth, FB1 biosynthesis, and virulence, but dispensable for sexual reproduction in F. verticillioides. The study presents the kexin-like protein as a potential drug target for the management of the devastating maize ear and stalk rot diseases. Further studies should aim at uncovering the link between FvKex2 activity and FB1 biosynthesis genes. Key points: •The kexin-like protein FvKex2 contributes significantly to the vegetative growth of Fusarium verticillioides. •The conserved protein is required for fungal conidiation and conidial morphology, but dispensable for sexual reproduction. •Deletion of FvKEX2 greatly attenuates the virulence and mycotoxin production potential of F. verticillioides. [ABSTRACT FROM AUTHOR]

Fusarium verticillioides is one of the most important fungal pathogens causing maize ear and stalk rots, thereby undermining global food security. Infected seeds are usually unhealthy for consumption due to contamination with fumonisin B1 (FB1) mycotoxin produced by the fungus as a virulence factor. Unveiling the molecular factors that determine fungal development and pathogenesis will help in the control and management of the diseases. Kex2 is a kexin-like Golgi-resident proprotein convertase that is involved in the activation of some important proproteins. Herein, we identified and functionally characterized FvKex2 in relation to F. verticillioides development and virulence by bioinformatics and functional genomics approaches. We found that FvKex2 is required for the fungal normal vegetative growth, because the growth of the ∆Fvkex2 mutant was significantly reduced on culture media compared to the wild-type and complemented strains. The mutant also produced very few conidia with morphologically abnormal shapes when compared with those from the wild type. However, the kexin-like protein was dispensable for the male role in sexual reproduction in F. verticillioides. In contrast, pathogenicity was nearly abolished on wounded maize stalks and sugarcane leaves in the absence of FvKEX2 gene, suggesting an essential role of Fvkex2 in the virulence of F. verticillioides. Furthermore, high-performance liquid chromatography analysis revealed that the ∆Fvkex2 mutant produced a significantly lower level of FB1 mycotoxin compared to the wild-type and complemented strains, consistent with the loss of virulence observed in the mutant. Taken together, our results indicate that FvKex2 is critical for vegetative growth, FB1 biosynthesis, and virulence, but dispensable for sexual reproduction in F. verticillioides. The study presents the kexin-like protein as a potential drug target for the management of the devastating maize ear and stalk rot diseases. Further studies should aim at uncovering the link between FvKex2 activity and FB1 biosynthesis genes. Key points: •The kexin-like protein FvKex2 contributes significantly to the vegetative growth of Fusarium verticillioides. •The conserved protein is required for fungal conidiation and conidial morphology, but dispensable for sexual reproduction. •Deletion of FvKEX2 greatly attenuates the virulence and mycotoxin production potential of F. verticillioides. [ABSTRACT FROM AUTHOR]

The renewable‐energy‐powered electroreduction of nitrate (NO3−) to ammonia (NH3) has garnered significant interest as an eco‐friendly and promising substitute for the Haber–Bosch process. However, the sluggish kinetics hinders its application at a large scale. Herein, we first calculated the N‐containing species (*NO3 and *NO2) binding energy and the free energy of the hydrogen evolution reaction over Cu with different metal dopants, and it was shown that Zn was a promising candidate. Based on the theoretical study, we designed and synthesized Zn‐doped Cu nanosheets, and the as‐prepared catalysts demonstrated excellent performance in NO3−‐to‐NH3. The maximum Faradaic efficiency (FE) of NH3 could reach 98.4 % with an outstanding yield rate of 5.8 mol g−1 h−1, which is among the best results up to date. The catalyst also had excellent cycling stability. Meanwhile, it also presented a FE exceeding 90 % across a wide potential range and NO3− concentration range. Detailed experimental and theoretical studies revealed that the Zn doping could modulate intermediates adsorption strength, enhance NO2− conversion, change the *NO adsorption configuration to a bridge adsorption, and decrease the energy barrier, leading to the excellent catalytic performance for NO3−‐to‐NH3. [ABSTRACT FROM AUTHOR]

The renewable‐energy‐powered electroreduction of nitrate (NO3−) to ammonia (NH3) has garnered significant interest as an eco‐friendly and promising substitute for the Haber–Bosch process. However, the sluggish kinetics hinders its application at a large scale. Herein, we first calculated the N‐containing species (*NO3 and *NO2) binding energy and the free energy of the hydrogen evolution reaction over Cu with different metal dopants, and it was shown that Zn was a promising candidate. Based on the theoretical study, we designed and synthesized Zn‐doped Cu nanosheets, and the as‐prepared catalysts demonstrated excellent performance in NO3−‐to‐NH3. The maximum Faradaic efficiency (FE) of NH3 could reach 98.4 % with an outstanding yield rate of 5.8 mol g−1 h−1, which is among the best results up to date. The catalyst also had excellent cycling stability. Meanwhile, it also presented a FE exceeding 90 % across a wide potential range and NO3− concentration range. Detailed experimental and theoretical studies revealed that the Zn doping could modulate intermediates adsorption strength, enhance NO2− conversion, change the *NO adsorption configuration to a bridge adsorption, and decrease the energy barrier, leading to the excellent catalytic performance for NO3−‐to‐NH3. [ABSTRACT FROM AUTHOR]

High-quality cubic YSZ crystals were designed with various contents of Er3+, Tm3+ and Yb3+ to produce white light emission, and grown by the optical floating zone method. The up-conversion luminescence spectra of the crystals under 980 nm laser irradiation show three distinct groups of emission peaks at ∼473 nm (blue) generated by the Tm3+ 1 G 4 → 3 H 6 transition, 531 and 547 nm (green) from the Er3+ 2 H 11/2 → 4 I 15/2 and 4 S 3/2 → 4 I 15/2 transitions, and 640 and 662 nm (red) from the Er3+ 4 F 9/2 → 4 I 15/2 transition. The optical power curve obtained by plotting the up-conversion luminescence intensity against the laser power shows that the blue emission involves a three-photon process, whilst both the green and red emissions are the results of two-photon processes. Overall white light emission was observed with the crystal prepared with 0.05 mol% Er 2 O 3 , 0.5 mol% Tm 2 O 3 and 2.0 mol% Yb 2 O 3 , and this crystal is suitable for use in highly efficient white light emission devices. [ABSTRACT FROM AUTHOR]

A series of pyridinium-based chiral ionic liquid crystals were designed and synthesized. All of them exhibit enantiotropic smectic phases. The methylation on the pyridine ring not only decreases the melting point and clearing point, but also drives structural transitions from bilayer molecular packing structures to interdigitated monolayer ones at the smectic A and C phases. Due to entropy increase, the clearing point of the liquid crystal derived from 2-methylpyridine is higher than that derived from 3-methylpyridine, and then that derived from 4-methylpyridine. [ABSTRACT FROM AUTHOR]

Conventional breeding has produced low levels of yield increase in lentils (Lens culinaris ssp. culinaris Medik.) in recent decades. As hybrids have led to large increases in yield in other crops, we examined the possibility of using hybrids in lentils. In 52 hybrids between Australian commercial cultivars and lines from a global collection of cultivated and wild accessions, we found 15 of the hybrids had seed yield hybrid vigor, with better parent heterosis (BPH) gains ranging from 10.4 to 125%. Flowering time, seed size, cotyledon color, and branch number were important but not critical for the level of hybrid vigor in seed yield. Plant height at 28 days post sowing (dps) could be an indicator of seed yield vigor of hybrids grown in glasshouse conditions. In the absence of male sterile lines in lentils, we used high‐yielding hybrid combinations in a program of repeated selfing and selection to produce stable, high‐yielding lines (Hybrid Mimics) with grain yields similar to the F1 hybrids, avoiding the limitation of the hybrid advantage to the F1 generation. Seed yield increased in successive generations (F3–F5); yields of the F4 plants were close to that of the F1 hybrid. Our results indicate that there is potential for hybrid seed yield vigor in lentil to be accessed through hybrid mimic selection. This is a breeding method not dependent on male sterility that can be initiated with a low number of hand‐pollinated hybrids. Hybrid mimic breeding may be applicable to a wide range of crops. Core Ideas: Hybrids provide new opportunities in lentil breeding.Heterosis of seed yield was found in many lentil hybrids.High‐yielding, stable lines (Hybrid Mimics) can be selected from selfed hybrids. [ABSTRACT FROM AUTHOR]

A series of azobenzene liquid crystals containing one amino acid residue were synthesized. They exhibit smectic mesophases. The compounds derived from alanine can self-assemble into twisted nanoribbons. The molecules organized in a monolayer structure within the nanoribbon. Circular dichroism characterization indicated that the neighboring liquid crystal cores packed in a chiral structure. FT-IR spectra indicated that the nanoribbons were caused by H-bonding and association of hydrocarbon chains. [ABSTRACT FROM AUTHOR]

Objective. To summarize the commonalities and particularities of comfort care interventions for neurology and general surgery patients. Methods. The development of comfort care and its practical application in neurology and general surgery were discussed and summarized by searching the current literature on comfort care interventions for neurology and general surgery patients, including case reports, clinical studies, and systematic reviews. Results. Comfort nursing intervention is a kind of nursing intervention with integrity and creativity. In addition to its uniqueness, the comfort nursing model also has strong effectiveness. Clinical holistic nursing has been significantly improved through the application of comfort nursing intervention theory, and its nursing mode has enhanced the connotation of clinical nursing. Conclusion. Comfort nursing intervention for neurology and general surgery patients can help patients recover and deserves further promotion. [ABSTRACT FROM AUTHOR]

Copper is a toxic heavy metal that causes various damage when it accumulates in the body beyond the physiological threshold. Wilson disease (WD) is an inherited disorder characterized by impaired copper metabolism. Reproductive damage in male patients with WD is gradually attracting attention. However, the underlying mechanisms of copper toxicity are unclear. In this study, we investigated the role of inflammation and PANoptosis in testicular damage and impaired spermatogenesis caused by copper deposition using the WD model toxic milk (TX) mice. Copper chelator-penicillamine and toll-like receptor 4 (TLR4) inhibitor-eritoran were used to intervene in TX mice in our animal experiment methods. Testis samples were collected from mice for further analysis. The results showed that the morphology and ultrastructure of the testis and epididymis in TX mice were damaged, and the sperm counts decreased significantly. The TLR4/nuclear factor kappa-B (NF-κB) signaling pathway was activated by copper deposition, which led to the upregulation of serum and testicular inflammatory factors in TX mice. Meanwhile, pyroptosis, apoptosis, and necroptosis were significant in the testis of TX mice. Both chelated copper or inhibited TLR4 expression markedly suppressed the TLR4/NF-κB signaling pathway, thereby reducing the expression of inflammatory factors. PANoptosis in the testis of TX mice was also reversed. Our study indicated that pathological copper exposure induces inflammation and PANoptosis through the TLR4/NF-κB signaling pathway, leading to toxic testicular damage and impaired spermatogenesis in WD. • Copper deposition caused testicular damage and impaired spermatogenesis in toxic milk (TX) mice with Wilson disease. • Copper deposition activated the toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) signaling pathway. • Copper deposition induced PANoptosis (pyroptosis, apoptosis, and necroptosis) in the testis of TX mice. • Inhibition of TLR4 can alleviate the inflammatory damage and PANoptosis in the testis of TX mice. [ABSTRACT FROM AUTHOR]

In mammals, β-catenin participates in innate immune process through interaction with NF-κB signaling pathway. However, its role in teleost immune processes remains largely unknown. We aimed to clarify the function of β-catenin in the natural defense mechanism of Qi river crucian carp (Carassius auratus). β-catenin exhibited a ubiquitous expression pattern in adult fish, as indicated by real-time PCR analysis. Following lipopolysaccharide (LPS), Polyinosinic-polycytidylic acid (polyI: C) and Aeromonas hydrophila (A. hydrophila) challenges, β-catenin increased in gill, intestine, liver and kidney, indicating that β-catenin likely plays a pivotal role in the immune response against pathogen infiltration. Inhibition of the β-catenin pathway using FH535, an inhibitor of Wnt/β-catenin pathway, resulting in pathological damage of the gill, intestine, liver and kidney, significant decrease of innate immune factors (C3 , defb3 , LYZ-C , INF-γ), upregulation of inflammatory factors (NF-κB , TNF-α , IL-1 , IL-8), and downregulation of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) activities, increase of Malondialdehyde (MDA) content. Following A. hydrophila invasion, the mortality rate in the FH535 treatment group exceeded that of the control group. In addition, the diversity of intestinal microflora decreased and the community structure was uneven after FH535 treatment. In summary, our findings strongly suggest that β-catenin plays a vital role in combating pathogen invasion and regulating intestinal flora in Qi river crucian carp. • β-catenin were upregulated in different tissues after pathogen challenge.. • Inhibition of β-catenin led to pathological damage of tissues.. • Inhibition of β-catenin resulted in low immune defense capacity. • Inhibition of β-catenin destroyed intestinal flora structure. [ABSTRACT FROM AUTHOR]

Two series of acrylate liquid crystals with enantiotropic SmA and SmC phases were synthesised. With increasing the alkoxy chain length, SmC phase was favourable to be formed. The mesophases were confirmed by taking small angle X-ray scattering patterns. Moreover, a diacrylate liquid crystal with an enantiotropic SmA phase was synthesised. Smectic liquid crystal mixtures were prepared using the diacrylate liquid crystal (or a mixture of an acrylate liquid crystal and the diacrylate one) and a dichroic dye. After photopolymerisation at the SmA phase, polymeric polarisers were obtained. The degree of polarisation was increased with increasing the dye concentration and film thickness. [ABSTRACT FROM AUTHOR]

• The effects of sleep duration and quality on knee osteoarthritis were unclear. • Only short sleep duration was associated with increased risk of knee osteoarthritis. • Poor sleep quality was associated with increased risk of knee osteoarthritis. • Adequate and restful sleep benefits the health of middle-aged and older adults in Chinese. The association between nighttime sleep duration and sleep quality with the risk of knee osteoarthritis (OA) remains unclear. This study aimed to examine the longitudinal association among middle-aged and older adults in China. The data used in this study were obtained from the China Health and Retirement Longitudinal Study (CHARLS) surveys conducted in 2011 and 2015. Nighttime sleep duration was categorized into five groups: <6 h, 6 to <7 h, 7 to <8 h, 8 to <9 h, and ≥9 h/night. Sleep quality was assessed by restless days in the past week (<1, 1–2, 3–4, and 5–7 days/week). Multivariate logistic regression models were used to assess the association between sleep duration and quality with incident knee OA. A total of 11,114 participants who did not have knee OA at baseline were enrolled in this study. After 4 years of follow-up, the overall incidence of knee OA was 8.07 %. Compared to 7 to <8 h of sleep duration, short sleep duration (<6 h/night) was associated with a significantly increased risk of incident knee OA in the fully adjusted model [odds ratio (OR) =1.73, 95 % confidence interval (CI): 1.33–2.25]. Additionally, participants with 5–7 sleep restless days/week were associated with significantly increased risk of incident knee OA (OR = 1.88, 95 % CI: 1.48–2.38). Short nighttime sleep duration and poor sleep quality are associated with increased risk of incident knee OA. [ABSTRACT FROM AUTHOR]

A series of organosilane liquid crystals (OSn) with different alkoxy chain lengths were synthesised. Both enantiotropic nematic and SmC phases were identified. With increasing the alkoxy chain length, SmC phase is feasible to be formed. Both the clearing points and SmC-nematic transition temperatures show odd-even effects. Small angle X-ray scattering characterisation indicated that the SmC phase of OS6 showed a mono-layered structure. Cholesteric liquid crystal mixtures were prepared using OS1, a bola-type organosilane (Bola-1) and a chiral dopant. After polycondensation under an acidic condition, structurally coloured organic–inorganic hybrid silica films were obtained. With increasing the weight ratio of Bola-1/OS1, the reflection band of the film shifted to short wavelength. [ABSTRACT FROM AUTHOR]

Cerebrovascular reactivity (CVR) deficits in adolescents with concussion may persist after resolution of neurological symptoms. Whether or not CVR deficits predict long term neurological function is unknown. We used adolescent mice closed head injury (CHI) models (54 g, 107 cm or 117 cm drop height), followed by blood oxygenation level dependent (BOLD)-functional MRI with CO2 challenge to assess CVR and brain connectivity. At one week, 3HD 107 cm mice showed delayed BOLD responses (p = 0.0074), normal striatal connectivity, and an impaired respiratory rate response to CO2 challenge (p = 0.0061 in ΔRmax). The 107 cm group developed rotarod deficits at 6 months (p = 0.02) and altered post-CO2 brain connectivity (3-fold increase in striatum to motor cortex correlation coefficient) by one year, but resolved their CVR and respiratory rate impairments, and did not develop cognitive or circadian activity deficits. In contrast, the 117 cm group had persistent CVR (delay time: p = 0.016; washout time: p = 0.039) and circadian activity deficits (free-running period: 23.7 hr in sham vs 23.9 hr in 3HD; amplitude: 0.15 in sham vs 0.2 in 3HD; peak activity: 18 in sham vs 21 in 3HD) at one year. Persistent CVR deficits after concussion may portend long-term neurological dysfunction. Further studies are warranted to determine the utility of CVR to predict chronic neurological outcome after mild traumatic brain injury. [ABSTRACT FROM AUTHOR]

A series of pyridinium-based chiral ionic liquid crystals were designed and synthesized. All of them exhibit enantiotropic smectic phases. The methylation on the pyridine ring not only decreases the melting point and clearing point, but also drives structural transitions from bilayer molecular packing structures to interdigitated monolayer ones at the smectic A and C phases. Due to entropy increase, the clearing point of the liquid crystal derived from 2-methylpyridine is higher than that derived from 3-methylpyridine, and then that derived from 4-methylpyridine. [ABSTRACT FROM AUTHOR]

Neuregulin (NRG)1 - ErbB receptor signaling has been shown to play an important role in the biological function of peripheral microvascular endothelial cells. However, little is known about how NRG1/ErbB signaling impacts brain endothelial function and blood-brain barrier (BBB) properties. NRG1/ErbB pathways are affected by brain injury; when brain trauma was induced in mice in a controlled cortical impact model, endothelial ErbB3 gene expression was reduced to a greater extent than that of other NRG1 receptors. This finding suggests that ErbB3-mediated processes may be significantly compromised after injury, and that an understanding of ErbB3 function would be important in the of study of endothelial biology in the healthy and injured brain. Towards this goal, cultured brain microvascular endothelial cells were transfected with siRNA to ErbB3, resulting in alterations in F-actin organization and microtubule assembly, cell morphology, migration and angiogenic processes. Importantly, a significant increase in barrier permeability was observed when ErbB3 was downregulated, suggesting ErbB3 involvement in BBB regulation. Overall, these results indicate that neuregulin-1/ErbB3 signaling is intricately connected with the cytoskeletal processes of the brain endothelium and contributes to morphological and angiogenic changes as well as to BBB integrity. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is one of the key commercial chemicals and carbon-free energy carriers. It is mainly made by Haber-Bosch process under high temperature and high pressure, which consumes huge amount of energy and releases large amounts of CO2. Developing sustainable approaches to its production is of great importance. Powered by a renewable electricity source, electrochemical N2 reduction reaction (NRR) and nitrate reduction reaction (NITRR) are potential routes to synthesize NH3 under ambient conditions. This review summarizes major recent advances in the NRR and NITRR, especially for several years. Some fundamentals for NRR and NITRR are first introduced. Afterward, the design strategies of nanocatalysts are discussed, mainly focusing on nano-structure construction/nanoconfinement, doping/defects engineering and single-atom engineering. Finally, the critical challenges remaining in this research area and promising directions for future research are discussed. [ABSTRACT FROM AUTHOR]

Receptor-interacting protein kinase-1 (RIPK1) is a master regulator of cell death and inflammation, and mediates programmed necrosis (necroptosis) via mixed-lineage kinase like (MLKL) protein. Prior studies in experimental intracerebral hemorrhage (ICH) implicated RIPK1 in the pathogenesis of neuronal death and cognitive outcome, but the relevant cell types involved and potential role of necroptosis remain unexplored. In mice subjected to autologous blood ICH, early RIPK1 activation was observed in neurons, endothelium and pericytes, but not in astrocytes. MLKL activation was detected in astrocytes and neurons but not endothelium or pericytes. Compared with WT controls, RIPK1 kinase-dead (RIPK1D138N/D138N) mice had reduced brain edema (24 h) and blood-brain barrier (BBB) permeability (24 h, 30 d), and improved postinjury rotarod performance. Mice deficient in MLKL (Mlkl-/-) had reduced neuronal death (24 h) and BBB permeability at 24 h but not 30d, and improved post-injury rotarod performance vs. WT. The data support a central role for RIPK1 in the pathogenesis of ICH, including cell death, edema, BBB permeability, and motor deficits. These effects may be mediated in part through the activation of MLKL-dependent necroptosis in neurons. The data support development of RIPK1 kinase inhibitors as therapeutic agents for human ICH. [ABSTRACT FROM AUTHOR]

Purpose: Opioids are a mainstay for pain management after total joint arthroplasty (TJA). The prevalence and risk factors for prolonged opioid use after TJA are important to understand to help slow the opioid epidemic. We aim to summarize and evaluate the prevalence and time trend of prolonged opioid use after TJA and pool its risk factors.Methods: Following the preferred reporting items for systematic reviews and meta-analysis statement, we systematically searched PubMed, the Cochrane Library, and EMBASE, etc. from inception up to October 1, 2019. Cohort studies reporting risk factors for prolonged opioids use (≥ 3 months) after TJA were included. Studies characteristics, risk ratios (RR), and prevalence of prolonged opioid use were extracted and synthesized.Results: A total of 15 studies were published between 2015 and 2019, with 416,321 patients included. 12% [95%CI 10-14%] of patients had prolonged opioid use after TJA and its time trend was associated with median enrollment years (P = 0.0013). Previous opioid use (RR = 1.73; P < 0.001), post-traumatic stress disorder (RR = 1.34; P < 0.001), benzodiazepine use (RR = 1.38; P < 0.001), tobacco abuse (RR = 1.26; P < 0.001), fibromyalgia (RR = 1.51; P < 0.001), and back pain (RR = 1.34; P < 0.001) were the largest effective risk factors for prolonged use of opioids.Conclusions: To our knowledge, this is the first meta-analysis determining the risk factors of prolonged opioid use and characterizing its rate and time trend in TJA. Understanding risk factors for patients with higher potential for prolonged opioids use can be used to implement appropriate management strategies, reduce unsafe opioid prescriptions, and decrease the risk of prolonged opioid use after TJA. [ABSTRACT FROM AUTHOR]

A series of fluorinated compounds with an amino acid residue are synthesized, which show smectic phases. The bulkiness of the side group of the amino acid residue plays an important role in the temperature ranges of the mesophases and clearing points. The compound with a glycine residue exhibits the widest mesomorphic temperature range. However, the compound with a cyclohexylglycine residue exhibits only a monotropicSmA phase. The phenyl groups of the amino acid residues also strongly affect the formation of mesophase. With decreasing the distance between the chiral center and the phenyl group, the temperature range of the mesophase decreases. [ABSTRACT FROM AUTHOR]

Background: Brassica rapa is an important oilseed and vegetable crop species and is the A subgenome donor of two important oilseed Brassica crops, Brassica napus and Brassica juncea. Although seed size (SZ), seed color (SC), and oil content (OC) substantially affect seed yield and quality, the mechanisms regulating these traits in Brassica crops remain unclear. Results: We collected seeds from a pair of B. rapa accessions with significantly different SZ, SC, and OC at seven seed developmental stages (every 7 days from 7 to 49 days after pollination), and identified 28,954 differentially expressed genes (DEGs) from seven pairwise comparisons between accessions at each developmental stage. K-means clustering identified a group of cell cycle-related genes closely connected to variation in SZ of B. rapa. A weighted correlation analysis using the WGCNA package in R revealed two important co-expression modules comprising genes whose expression was positively correlated with SZ increase and negatively correlated with seed yellowness, respectively. Upregulated expression of cell cycle-related genes in one module was important for the G2/M cell cycle transition, and the transcription factor Bra.A05TSO1 seemed to positively stimulate the expression of two CYCB1;2 genes to promote seed development. In the second module, a conserved complex regulated by the transcription factor TT8 appear to determine SC through downregulation of TT8 and its target genes TT3, TT18, and ANR. In the third module, WRI1 and FUS3 were conserved to increase the seed OC, and Bra.A03GRF5 was revealed as a key transcription factor on lipid biosynthesis. Further, upregulation of genes involved in triacylglycerol biosynthesis and storage in the seed oil body may increase OC. We further validated the accuracy of the transcriptome data by quantitative real-time PCR of 15 DEGs. Finally, we used our results to construct detailed models to clarify the regulatory mechanisms underlying variations in SZ, SC, and OC in B. rapa. Conclusions: This study provides insight into the regulatory mechanisms underlying the variations of SZ, SC, and OC in plants based on transcriptome comparison. The findings hold great promise for improving seed yield, quality and OC through genetic engineering of critical genes in future molecular breeding. [ABSTRACT FROM AUTHOR]

Myostatin, through type I receptor (kinase 4, 5, ALK4/5), functions to participate in the immune system and negatively regulate muscle growth in mammals. However, the role of myostatin (mstn) in the immune system of teleosts is largely unknown. In a previous study, we cloned the mstn1 cDNA encoding myostatin in Qi river crucian carp (Carassius auratus). In the present study, we have cloned mstn2 cDNA, which was characterized and analyzed together with mstn1. Tissue distribution analysis showed that both mstn genes are expressed in numerous tissues, with mstn1 dominantly expressed in the muscle and brain, whereas mstn2 is mainly expressed in the brain. During embryogenesis, mstn1 and mstn2 exhibit different expression patterns. Both mstn1 and mstn2 expression increased stepwise in the brain at different developmental stages. Furthermore, both genes are differentially regulated during different periods of fasting/re-feeding. Following the exposure of C. auratus to polyI:C, lipopolysaccharide (LPS), and Aeromonas hydrophila , both genes were upregulated in different tissues, which indicated that they might be involved in the immune response against pathogenic invasion. Blocking the Mstn signal pathway with SB-431542 (a chemical inhibitor of ALK4/5) resulted in significantly increased body length and weight. However, the mortality of SB-431542-treated fish was higher after A. hydrophila challenge. Moreover, decreased expression of lysozymes (lyz), complement component 3 (c3), β-defensin 3 (defb3), and interferon γ (ifnγ) were exhibited in treated fish, compared with the controls. Furthermore, the expression of nf-κb1 , three pro-inflammatory cytokines (il1 β , il6, and tnfα), and inflammatory cytokines (il8 and il10) were significantly increased in both the SB-431542-treated group and the control after A. hydrophila infection, suggesting that the NF-κB pathway was not suppressed in the SB-431542-treated fish. Taken together, our data suggest that both mstn1 and mstn2 play important roles in early body development, muscle growth, and the immune system by acting downstream of the NF-κB signal pathway. • Mstn1 and mstn2 exhibit different tissue distribution patterns. • Both mstn genes increased stepwise in the brain at different developmental stages. • Two mstn genes were upregulated in different tissues after pathogen challenge. • Inhibition of Mstn signal pathway resulted in larger body size, but low immune defense capacity. [ABSTRACT FROM AUTHOR]

Four compounds containing two lactate groups and one perfluorocarbon chain are designed and synthesised, whose chirality is tuned by changing the chirality of the lactic acid residues. (R,S)- and (S,R)-2 stereoiosomers exhibit an enantiotropic SmA phase, while (R,R)- and (S,S)-2 stereoisomers exhibit an enantiotropic SmA phase and an enantiotropic SmCd* one. Therefore, the chirality of the compounds plays an important role in the mesomorphic behaviours of the compounds. The optical activity of these liquid crystals is dominated by the chirality of the lactate group near the core. (R)- and (S)-1 with one lactic acid residue and one perfluorocarbon chain exhibit only an enantiotropic SmA phase. [ABSTRACT FROM AUTHOR]

A series of fluorinated compounds with an L-alanine residue are synthesised. Both enantiotropic SmA and SmC* phases were identified. The clearing points decreased with increasing the alkoxy chain length. The intramolecular hydrogen bond was proposed to decrease the melting points of them and broaden the temperature ranges of the mesophases. The optical purity also played an important role in the thermostability of the mesophases. The compounds derived from L-butyrine and L-norvaline also show SmA and SmC* phases. The clearing point decreases with increasing the alkyl chain length of the amino acid residue. [ABSTRACT FROM AUTHOR]

Repetitive mild traumatic brain injury during adolescence can induce neurological dysfunction through undefined mechanisms. Interleukin-1 (IL-1) contributes to experimental adult diffuse and contusion TBI models, and IL-1 antagonists have entered clinical trials for severe TBI in adults; however, no such data exist for adolescent TBI. We developed an adolescent mouse repetitive closed head injury (rCHI) model to test the role of IL-1 family members in post-injury neurological outcome. Compared to one CHI, three daily injuries (3HD) produced acute and chronic learning deficits and emergence of hyperactivity, without detectable gliosis, neurodegeneration, brain atrophy, and white matter loss at one year. Mature IL-1β and IL-18 were induced in brain endothelium in 3HD but not 1HD, three hit weekly, or sham animals. IL-1β processing was induced cell-autonomously in three-dimensional human endothelial cell cultures subjected to in vitro concussive trauma. Mice deficient in IL-1 receptor-1 or caspase-1 had improved post-injury Morris water maze performance. Repetitive mild CHI in adolescent mice may induce behavioral deficits in the absence of significant histopathology. The endothelium is a potential source of IL-1β and IL-18 in rCHI, and IL-1 family members may be therapeutic targets to reduce or prevent neurological dysfunction after repetitive mild TBI in adolescents. [ABSTRACT FROM AUTHOR]

Cholesteric liquid crystal polymer network (CLCN) films have attracted much attention for their applications as optical filters and in displays, decoration, and anti-counterfeiting. Herein, two pairs of chiral bola-type epoxy liquid crystals with a cholesteric mesophase were synthesized. Their mixtures exhibit thermochromic behaviour. CLCN films with structural colours were prepared using their mixtures through photopolymerization. The Bragg reflection band and the handedness of the CLCN film can be controlled by changing the weight ratio of the chiral liquid crystals. Patterned CLCN films were prepared based on their thermochromic behaviour, the addition of a luminescent compound, or the handedness of the liquid crystal mixture, and they were potentially applied in decoration and anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Both the colourful cholesteric liquid crystal polymer network (CLCN) patterns and the gratings have attracted much attention for their applications as optical materials. Herein, the photochromic cholesteric liquid crystal (CLC) mixtures were prepared using a photoisomerizable chiral dopant. The structural colour of the CLC mixtures was tunable by changing the chiral dopant concentration and the intensity of the 365-nm irradiation light. The CLCN gratings with a structural colour were prepared using the UV nanoimprinting lithography method. The structural colours of the CLCN gratings originate from both the cholesteric and the grating structures. Moreover, a patterned CLCN grating was prepared using a photochromic CLC mixture, which could be applied for decoration and anti-counterfeiting. [ABSTRACT FROM AUTHOR]

• Wnt4a expressed in the early differentiating ovaries in a natural triploid teleost. • In the sex reversed testis, expression level of CA-wnt4a was significantly downregulated. • Inhibition of Wnt/β-catenin signal pathway cause the female gonad masculinization. • Together with Foxl2-leading estrogen pathway, CA-wnt4a signaling favored ovarian differentiation. WNT4 (wingless-type MMTV integration site family, member 4) plays a key role in the ovarian differentiation and development in mammals. However, the possible roles of Wnt4 during gonadal differentiation and development need further clarification in teleosts. In this study, we cloned and characterized the full-length cDNA of Qi river crucian carp (Carassius auratus) wnt4a gene (CA-wnt4a). The cDNA of CA-wnt4a is 2337 bp, including the ORF of 1059 bp, encoding a putative protein with a transmembrane domain and a WNT family domain. Sequence and phylogenetic analyses revealed that the CA- Wnt4a identified is a genuine Wnt4a. Tissue distribution analysis showed that CA-wnt4a is expressed in all the tissues examined, including ovary. CA-wnt4a undergoes a stepwise increase in the embryonic stages, suggesting that CA-wnt4a might be involved in the early developmental stage. Ontogenic analysis demonstrated that CA-wnt4a expression is upregulated in the ovaries at 30–50 days after hatching (dah), the critical period of sex determination/differentiation in Qi river crucian carp. From 90 dah, the expression of CA-wnt4a was gradually downregulated in the developing ovaries. Immunohistochemistry demonstrated that CA- Wnt4a was expressed in the somatic and germ cells of the ovary by 30 dah, thereafter, positive signals of Wnt4a were detected in the somatic cells, oogonia and primary growth oocytes from 60 dah. In the sex-reversed testis induced by letrozole treatment, the expression level of CA-wnt4a was significantly downregulated. When CA-wnt4a expression was inhibited by injection of FH535 (an inhibitor of canonical Wnt/β-catenin signal pathway) in the ovaries, levels of cyp19a1a , foxl2 mRNA were significantly downregulated, while sox9b and cyp11c1 were upregulated, which suggested that together with Foxl2-leading estrogen pathway, CA-wnt4a signaling pathway might be involved in ovarian differentiation and repression of the male pathway gene expression in Qi river crucian carp. [ABSTRACT FROM AUTHOR]

Abstract The piston secondary motion is the most predominant excitation source for the mechanical vibration of diesel engine, which is directly affected by the piston profile. The effects of piston skirt profile on the dynamic behavior of piston and the vibration characteristics of engine block is studied synthetically by the method of a combination of experimental test and numerical simulation. The temperature distribution of the piston top surface under rated working condition is tested by a hardness plug, which is used as the boundary condition to carry out the thermodynamic simulation of diesel engine working process, to obtain the hot profile of the piston. Then, the dynamics model of piston assemblies are formally established, and the skirt profiles of different bump positions of the piston skirt are optimally designed. Based on the above analysis, a comprehensive study on the influence of bump position on the piston dynamic behavior is carried out. Then, applying the modal testing method for the engine block and crankshaft to establish the elastic multi-body dynamics model of diesel engine and load the piston slapping force at different bump positions, the vibration response of the surface structure under the action of different piston slapping forces is also studied. The results show that the mechanical vibration of engine block will become more severe with the hiking up of bump position at the piston skirt. Also, the vibration behavior of the engine block in the middle and high frequency section is very sensitive to the bump position of the piston skirt, especially in the frequency range of 1600 Hz–3150 Hz. In addition, vibration noise performance can be significantly improved by adjusting the bump position of piston skirt downwards. Particularly, the vibration noise performance can be best achieved when the bump position of piston skirt is 5 mm. [ABSTRACT FROM AUTHOR]

To overcome the drawback of UV light response in La 2 Ti 2 O 7 nanosheets, novel up-conversion carbon quantum dots (CQDs) with visible light response have been introduced on the surface of La 2 Ti 2 O 7 for efficient enhancement of photocatalytic performance. The resulted CQDs/La 2 Ti 2 O 7 samples were characterized by XRD, TEM, FT-IR, XPS and UV–vis, respectively. Rhodamine B (RhB) solution was chosen as the target organic pollutant to evaluate the photocatalytic activity under visible light irradiation. The results indicated that 5 wt% loading of CQDs composite exhibited the best performance. Both the up-converted photoluminescence behavior and their electron capturing ability of CQDs are considered as the main reasons for the enhanced photocatalytic abilities. [ABSTRACT FROM AUTHOR]

It was documented that 17α, 20β-dihydroxy-4-pregnen-3-one (DHP), a fish specific progestin, might play critical roles in spermatogenesis, sperm maturation and spermiation partially through activating nuclear receptor (Pgr). However, no direct evidence is available to demonstrate the functions of DHP in fish spermatogenesis. To further elucidate the roles of DHP in teleosts, we generated a pgr homozygous mutant line in XY Nile tilapia ( Oreochromis niloticus ). Pgr gene mutation resulted in the development of a smaller, thinner testis and a lower GSI compared with normal testis. Pgr gene knockout led to irregular arrangement of spermatogenic cysts, decline of sperm count and sperm motility. Significant decrease of spermatocytes and spermatozoa was observed, which was further proved by the PCNA and Ph3 staining. Real-time PCR analysis demonstrated that mutation of pgr gene resulted in a significant up-regulation of steroidogenesis-related genes of cyp17a , cyp11b2 , StAR , scc , 20β-HSD, and sf1 , and down-regulation of fshb, fshr , oct4 , sycp3 , cdk1 , prm , cyclinB1 , cyclinB2 and cdc25 genes. Furthermore, both Immunohistochemistry and Western blotting experiments revealed a remarkable increase of Cyp17a1, Cyp17a2 and Cyp11b2 expressions in the pgr −/− testis. EIA measurement showed that an evident increase of 11-KT level was found in the pgr −/− XY fish. There was a significant increase in the mortality of offspring when crossing pgr −/− XY fish with wild type XX fish. Increased TUNEL staining and enhanced apoptosis maker gene ( bax ) expressions were also observed. Taken together, our data suggested that DHP-activated physiology via pgr is crucial for the fertility in the XY tilapia. [ABSTRACT FROM AUTHOR]

Double-layered polymer-stabilised cholesteric liquid crystal (PSCLC) films constructed from epoxy resin and polyacrylate were prepared based on photopolymerisation-induced phase separation. Moreover, a PSCLC film with an interpenetrating network was prepared through a one-step photopolymerisation approach. A colourful pattern was prepared based on these two approaches, which was suitably applied for decoration. [ABSTRACT FROM AUTHOR]

Natural weather systems possess certain spatiotemporal variability and correlations. Preserving these spatiotemporal properties is a significant challenge in postprocessing ensemble weather forecasts. To address this challenge, several rank-based methods, the Schaake Shuffle and its variants, have been developed in recent years. This paper presents an extensive assessment of the Schaake Shuffle and its two variants. These schemes differ in how the reference multivariate rank structure is established. The first scheme (SS-CLM), an implementation of the original Schaake Shuffle method, relies on climatological observations to construct rank structures. The second scheme (SS-ANA) utilizes precipitation event analogs obtained from a historical archive of observations. The third scheme (SS-ENS) employs ensemble members from the Global Ensemble Forecast System (GEFS). Each of the three schemes is applied to postprocess precipitation ensemble forecasts from the GEFS for its first three forecast days over the mid-Atlantic region of the United States. In general, the effectiveness of these schemes depends on several factors, including the season (or precipitation pattern) and the level of gridcell aggregation. It is found that 1) the SS-CLM and SS-ANA behave similarly in spatial and temporal correlations; 2) by a measure for capturing spatial variability, the SS-ENS outperforms the SS-ANA, which in turn outperforms the SS-CLM; and 3), overall, the SS-ANA performs better than the SS-CLM. The study also reveals that it is important to choose a proper size for the postprocessed ensembles in order to capture extreme precipitation events. [ABSTRACT FROM AUTHOR]

In higher plants, invertases hydrolyze sucrose (Suc), the major end product of photosynthesis, into glucose (Glc) and fructose (Fru), which are used as nutrients, energy sources, and signaling molecules for plant growth, yield formation, and stress responses. The invertase enzymes, named CWINs, VINs, and CINs, are located in the cell wall, vacuole, and cytosol, respectively. We hypothesize, based on their distinctive subcellular locations and physiological roles, that invertases may have undergone different modes during evolution with important functional implications. Here, we provide phylogenetic and functional genomic evidence that CINs are evolutionarily and functionally more stable compared with CWINs and VINs, possibly reflecting their roles in maintaining cytosolic sugar homeostasis for cellular function, and that CWINs have coevolved with the vasculature, likely as a functional component of phloem unloading. [ABSTRACT FROM AUTHOR]

There are considerable evidence of reproductive impairment in male organisms with Wilson disease (WD). The purpose of this study was to observe spermatogenesis, mitochondrial damage, apoptosis, and the level of oxidative stress in the testes of Wilson disease model TX mice, and to observe the effect and mechanism of glutathione on testicular spermatogenesis. Mice were divided into a normal control group (control group), Wilson disease model TX mice group (WD group), penicillamine-treated TX mice group (penicillamine group) and glutathione-treated TX mice group (glutathione group). Testicular coefficient, histomorphology of testis and epididymis, number of spermatozoa, apoptosis of spermatogenic cells and expression of apoptosis-related proteins were observed. Ultrastructural analysis of mitochondria and mitochondrial membrane potential (MMP) monitored using JC-1 dye were used to detect mitochondrial damage. The levels of malondialdehyde (MDA), glutathione (GSH), catalase (CAT), and reactive oxygen species (ROS) in testicular cells were measured to assess oxidative stress. Testicular coefficient did not change in mice with Wilson disease. However, the tissue structure of the testicular seminiferous tubules was damaged, and the number of spermatozoa in the epididymal lumen was significantly reduced in WD group. The apoptosis rate in the testes was significantly increased. The protein expression of the pro-apoptotic proteins Bax and Caspase-3 significantly increased, and the expressions of the anti-apoptotic protein Bcl-2 significantly decreased. The levels of ROS and MDA significantly increased, and the levels of CAT and GSH significantly decreased. Mitochondria with abnormal ultrastructure and the rate of JC-1 positive cells were significantly increased in the WD group. After copper chelation by penicillamine, the structure of the testicular seminiferous tubules and the number of spermatozoa in the epididymal lumen were significantly improved. The number of apoptotic cells was significantly reduced. The levels of Bax and Caspase-3 decreased, and the expression of Bcl-2 increased. The contents of CAT and GSH increased, and the levels of ROS and MDA decreased significantly. The abnormal mitochondria and JC-1 positive cells was significantly decreased. The histomorphology of seminiferous tubules, spermatogenic function, apoptosis rate, apoptosis-related proteins, mitochondrial damage, and oxidative stress in Wilson disease TX mice significantly improved after glutathione treatment. Copper deposition in Wilson disease can lead to oxidative stress injury, mitochondrial damage, and apoptosis in the testis, leading to the impairment of spermatogenesis. Glutathione may improve testicular spermatogenesis in male Wilson disease TX mice by inhibiting copper deposition-induced oxidative stress, mitochondrial damage, and apoptosis. [Display omitted] • Copper deposition caused impaired spermatogenesis in mice with Wilson disease (WD). • 2、Copper deposition caused oxidative stress, mitochondrial damage, and apoptosis in WD. • 3、Glutathione improved spermatogenesis in testis of mice with WD. • 4、Glutathione inhibited oxidative stress, mitochondrial damage, and apoptosis. [ABSTRACT FROM AUTHOR]

Handedness inversion has been widely studied in supramolecular chemistry and material sciences. Herein, a photoisomerizable chiral dopant was synthesized, which could induce the formation of a cholesteric phase with right‐handedness. The Bragg reflection band of the cholesteric liquid crystal (CLC) mixture shifted to the long wavelength with extending 365 nm UV light irradiation time. Based on this photochromic property, a colourful polymer‐stabilized CLC (PSCLC) film was prepared using a grayscale mask. A handedness reversible CLC mixture was prepared using a mixture of this chiral dopant and S5011. With extending the UV light irradiation time, the handedness of the CLC mixture changed from right‐ to left‐handedness. A patterned PSCLC film was prepared using this CLC mixture. Complementary images were observed under right‐ and left‐handedness circularly polarized lights. The results shown here not only give us a better understanding the competition between photopolymerization and photoisomerization, but also lay the foundations for decoration and anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Fertilization failure refers to the failure in the pronucleus formation, evaluating 16-18 h post in vitro fertilization or intracytoplasmic sperm injection. It can be caused by sperm, oocytes, and sperm-oocyte interaction and lead to great financial and physical stress to the patients. Recent advancements in genetics, molecular biology, and clinical-assisted reproductive technology have greatly enhanced research into the causes and treatment of fertilization failure. Here, we review the causes that have been reported to lead to fertilization failure in fertilization processes, including the sperm acrosome reaction, penetration of the cumulus and zona pellucida, recognition and fusion of the sperm and oocyte membranes, oocyte activation, and pronucleus formation. Additionally, we summarize the progress of corresponding treatment methods of fertilization failure. This review will provide the latest research advances in the genetic aspects of fertilization failure and will benefit both researchers and clinical practitioners in reproduction and genetics. [ABSTRACT FROM AUTHOR]

Selective abortion of grain siblings in a panicle or ear is conserved in cereals, and severely limits yield potential. The fate of grain siblings is established during or soon after fertilization, a narrow window of high sensitivity to stresses. Grain set is sink-limited, as leaf photosynthesis has reached the maximum and the amount of assimilates required (mainly as sucrose) for grain set is small. Understanding sugar import into, and metabolism within, the ovaries and grains is essential for designing approaches to alleviate abortion, thereby increasing yield, an urgent task facing humankind. An inherent asynchrony in pollination and fertilization among ovaries of a spike or ear determines the spatiotemporal hierarchy in sugar uptake potential and grain fate. Emerging findings support the idea of a complex regulation of sugar delivery across the grain maternal–filial interface, a critical step for grain set. As an evolutionary strategy, plants overproduce ovaries as a safety net for survival, with those losing in the competition for resources being aborted. Grain abortion is, however, highly detrimental agronomically. The molecular basis of selective abortion of grain siblings remains unknown. In this opinion article we assess the current understanding of the molecular players controlling carbon resource import into ovaries and young grains, followed by an evaluation of the spatial hierarchy of sink capacity among grain siblings, focusing on the roles exerted by sugar transporters and enzymes. We argue that, upon sequential pollination and fertilization, robust activation of the carbon import and sugar signaling system plays a key role in establishing the capacity of grain siblings to acquire enough carbon resources to survive and thrive. [ABSTRACT FROM AUTHOR]

Colourful polymer-stabilised cholesteric liquid crystal (PSCLC) film attracted much attention for their applications in decoration and anti-counterfeiting. Herein, a chiral dopant was synthesised using trans-p-hexoxycinnamic acid. With the addition of this chiral dopant in a reactive LC mixture, both thermochromic and photochromic phenomena were found. The Bragg reflection band of the CLC mixture shifted to long wavelength with extending 365-nm UV light irradiation time or increasing temperature. The structural colour can cover the visible range. The photochromic property of the CLC mixture was driven by the photoisomerisation of the chiral dopant. Colourful PSCLC patterns were prepared based on the thermochromic and/or photochromic properties and using masks. The results shown here not only give us a better understanding the competition between photopolymerisation and photoisomerisation, but also lay a foundation for the preparation of the decorations. [ABSTRACT FROM AUTHOR]

Sucrose (Suc) is the major end product of photosynthesis in mesophyll cells of most vascular plants. It is loaded into phloem of mature leaves for long-distance translocation to non-photosynthetic organs where it is unloaded for diverse uses. Clearly, Suc transport and metabolism is central to plant growth and development and the functionality of the entire vascular system. Despite vast information in the literature about the physiological roles of individual sugar metabolic enzymes and transporters, there is a lack of systematic evaluation about their molecular regulation from transcriptional to post-translational levels. Knowledge on this topic is essential for understanding and improving plant development, optimizing resource distribution and increasing crop productivity. We therefore focused our analyses on molecular control of key players in Suc metabolism and transport, including: (i) the identification of promoter elements responsive to sugars and hormones or targeted by transcription factors and microRNAs degrading transcripts of target genes; and (ii) modulation of enzyme and transporter activities through protein-protein interactions and other post-translational modifications. We have highlighted major remaining questions and discussed opportunities to exploit current understanding to gain new insights into molecular control of carbon partitioning for improving plant performance. [ABSTRACT FROM AUTHOR]

We propose a high-index-contrast AlGaAs microring waveguide for efficient second harmonic generation (SHG) under near-infrared pump. The good overlap occurs between the fundamental modes of pump and second harmonic wave owing to the strong field confinement. The phase matching and resonance conditions can be satisfied through choosing appropriate height and width of the waveguide. In order to deal with the depleted-pump situation and pulse-pumped nonlinear progress, we investigate the wavelength conversion progress by employing the discrete numerical method. The dependence of conversion efficiency on coupling coefficient, pump power and pump wavelength under continuous-wave pump are analysed systematically, and the conversion efficiency can be up to 0.45 for large-scale coupling coefficients with dB/cm under 30 mW pump. In addition, the pulse-pumped SHG progress is also simulated. Such discrete method also has potential in investigating other resonator-enhanced second-order or third-order nonlinear processes. [ABSTRACT FROM AUTHOR]

• The opposed-piston FPEG test platform is built. • The continuous and stable operation of the prototype is realized. • The appropriate ignition and injection timing and scavenge pressure are determined. • The stable operation mechanism and synchronization error of the system are analyzed. As a novel energy conversion device, opposed-piston free piston engine generator (FPEG) has high energy conversion efficiency, high power density, low heat transfer loss and excellent NVH performance. The opposed-piston FPEG test platform is built, and the continuous and stable operation of the prototype is realized. The influence laws of key parameters such as fuel injection timing, ignition timing, fuel injection quantity, scavenging pressure and rebound cylinder initial pressure on the performance of the system are systematically analyzed, the suitable value for the opposed-piston FPEG is determined, and the stable operation mechanism and synchronization error of the system are analyzed. It is found that there is a matching relationship between injection timing and ignition timing. The injection position should be set at 37 mm-39 mm, the ignition position should be 25–27 mm, and the injection and ignition interval should be controlled at about 12 mm. The peak in-cylinder pressure increases with the increase of fuel injection quantity, and the fuller the P-V diagram is. When the scavenging pressure is 1.5 bar and the ignition position is 25 mm-27 mm, the basic indexes have extreme points. When the ignition position is 27 mm, the peak in-cylinder pressure is the largest and the engine indicated thermal efficiency is the highest. When the initial pressure of rebound cylinder is 1.7 bar, the indicated thermal efficiency is the highest. Under the trajectory tracking control strategy, the system realizes continuous and stable operation and can deal with large cylinder pressure fluctuation. The synchronization error changes periodically and is relatively large in the middle of the expansion stroke and near the outer dead center. [ABSTRACT FROM AUTHOR]

The opposed-piston free piston engine generator (FPEG) has unique advantages because of its symmetrical structure and the cancellation of cylinder head. In this paper, a novel method which combines low frequency operation test with high frequency operation simulation is proposed to study the generation performance of linear generator in the full frequency operation range. The influences of operation frequency, stroke, power angle and load current on the generation performance of linear generator are analyzed. The results show that the resistive load can not efficiently absorb the electric energy generated by the linear machine, the system shows a small increase in power generation efficiency at high operation frequency, but exhibits a rapid upward trend in low-speed condition. When the generator operates under the rated condition of the opposed-piston FPEG, the generating power can reach 5 kW, and the generating efficiency is higher than 80%. Increasing the operation frequency can further improve the generating power of the generator due to the increasing energy input. • A novel method to analyze the power generation of opposed-piston FPEG is proposed. • The power generation increases with the increase of stroke and frequency. • The generation efficiency increases linearly with the stroke. • The growth rate of generation efficiency slows down at high speed region. [ABSTRACT FROM AUTHOR]

Two β-catenin ( β-cat ) genes exist in teleosts but little is known about their expression and function in ovarian development. We identified β-cat1 and β-cat2 from the Nile tilapia . β-cat1 and β-cat2 displayed a similar expression pattern in the ovary during development, and were mainly expressed in the oogonia and oocytes. In luciferase assays, β-cat1 activated the TOPFlash reporter dose-dependently, whereas β-cat2 failed to do so. Cotransfection of β-cat1 and β-cat2 synergistically enhanced the expression of the reporter. A specific interaction between β-cat1 and β-cat2 was also observed in a mammalian two-hybrid assay. Furthermore, tilapia recombinant Dkk1, an inhibitor of the β-cat pathway, decreased β-cat1 and β-cat2 , while increased sox9 , dmrt1, cyp11b2 and foxl2 expression in the in vitro cultured tilapia ovary, which could be abolished by simultaneous treatment with Bio, an agonist of β-cat. Consistently, β - cat1 or β - cat2 knockdown in XX fish by TALENs caused the retardation of ovarian differentiation and masculinization, as reflected by the upregulation of dmrt1 , cyp11b2 , sox9 , and serum 11-KT level. On the contrary, serum E2 level was unchanged even though foxl2 transcription was upregulated. These data suggestes that both β-cat1 and β-cat2 are important members and play synergistic roles in the canonical Wnt signal pathway in fish. Independent of Foxl2-leading estrogen pathway, they might be involved in ovarian differentiation and repression of the male pathway gene expression in tilapia. [ABSTRACT FROM AUTHOR]