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A facile method is proposed in this work to prepare a carbon paper (CP) with outstanding properties by doping boron to catalyze graphitization at lower temperature. Boron was introduced into CP by impregnating carbon fiber preform into a boron/phenolic resin/ethanol solution, and then CP was obtained after the consecutive procedures of hot pressing, carbonization, and graphitization. Morphology, microstructure, composition, and physical properties of the doped and undoped CPs were thoroughly investigated via various techniques to exam the effects of boron concentration and graphitization temperature. Furthermore, the boron doped CP was fabricated into fuel cell gas diffusion layer (GDL) and membrane electrode assembly (MEA) to evaluate its performance through the single cell performance. The findings indicated CP doping with 2 wt% boron could lower the graphitization temperature by at least 200 °C. The B-doped GDL had a higher power density in comparison with the undoped GDLs made in our lab or from the commercial brands. • The innovative preparation method for carbon paper with high conductivity. • The effect of boron concentration and graphitization temperature on carbon paper. • The single cell performance of B-doped gas diffusion layer. [ABSTRACT FROM AUTHOR]

Brucellosis is a zoonotic disease that affects wild and domestic animals. It is caused by members of the bacterial genus Brucella. Guanylate-binding protein 1 (GBP1) is associated with microbial infections. However, the role of GBP1 during Brucella infection remains unclear. This investigation aimed to identify the association of GBP1 with brucellosis. Results showed that Brucella infection induced GBP1 upregulation in RAW 264.7 murine macrophages. Small interfering GBP1 targeting RNAs were utilized to explore how GBP1 regulates the survival of Brucella intracellularly. Results revealed that GBP1 knockdown promoted Brucella 's survival ability, activated Nod-like receptor (NLR) containing a pyrin domain 3 (NLRP3) and absent in melanoma 2 (AIM2) inflammatory corpuscles, and induced pro-inflammatory cytokines IFN-γ and IL-1β. Furthermore, Brucella stimulated the expression of GBP1 in bone marrow-derived macrophages (BMDMs) and mice. During the inhibition of GBP1 in BMDMs, the intracellular growth of Brucella increased. In comparison, GBP1 downregulation enhanced the accumulation of Brucella -induced reactive oxygen species (ROS) in macrophages. Overall, the data indicate a significant role of GBP1 in regulating brucellosis and suggest the function underlying its suppressive effect on the survival and growth of Brucella intracellularly. • B. melitensis infection increased GBP1 expression in RAW 264.7 murine macrophages. • Knocking down the expression of GBP1 promotes Brucella infection RAW 264.7 murine macrophages. • Knocking down the expression of GBP1 induces the production of inflammatory cytokine in Brucella -infected macrophages. • Knocking down the expression of GBP1 promotes B. abortus persistence in bone marrow-derived macrophages. • Brucella infection increased GBP1 expression in vivo. [ABSTRACT FROM AUTHOR]

Spatial analyses of traffic crashes have drawn much interest due to the nature of the spatial dependence and spatial heterogeneity in the crash data. This study makes the best of Geographically Weighted Random Forest (GW-RF) model to explore the local associations between crash frequency and various influencing factors in the US, including road network attributes, socio-economic characteristics, and land use factors collected from multiple data sources. Special emphasis is put on modeling the spatial heterogeneity in the effects of a factor on crash frequency in different geographical areas in a data-driven way. The GW-RF model outperforms global models (e.g. Random Forest) and conventional geographically weighted regression, demonstrating superior predictive accuracy and elucidating spatial variations. The GW-RF model reveals spatial distinctions in the effects of certain factors on crash frequency. For example, the importance of intersection density varies significantly across regions, with high significance in the southern and northeastern areas. Low-grade road density emerges as influential in specific cities. The findings highlight the significance of different factors in influencing crash frequency across zones. Road network factors, particularly intersection density, exhibit high importance universally, while socioeconomic variables demonstrate moderate effects. Interestingly, land use variables show relatively lower importance. The outcomes could help to allocate resources and implement tailored interventions to reduce the likelihood of crashes. • Geographically weighted modeling with local Random Forest models. • Local associations between crash frequency and various factors in the USA. • Modeling and analyzing nonlinear effects of factors. • Revealing spatially distinctive effects of factors on crash frequency. [ABSTRACT FROM AUTHOR]

Age-related hearing loss (ARHL) is a common neurodegenerative disease. Its molecular mechanisms have not been fully elucidated. In the present study, we obtained differential mRNA expression in the cochlea of 2-month-old miR-29a +/+ mice and miR-29a −/− mice by RNA-seq. Gene ontology (GO) analysis was used to identify molecular functions associated with hearing in miR-29a −/− mice, including being actin binding (GO: 0003779) and immune processes. We focused on the intersection of differential genes, miR-29a target genes and the sensory perception of sound (GO:0007605) genes, with six mRNA at this intersection, and we selected Col1a1 as our target gene. We validated Col1a1 as the direct target of miR-29a by molecular and cellular experiments. Total 6 pathways involved in Col1a1 were identified by through Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. We selected the focal adhesion pathway as our target pathway based. Their expression levels in miR-29a −/− mice were verified by qRT-PCR and Western blot. Compared with miR-29a +/+ mice, the expression levels of Col1a1 , Itga4 , Itga2 , Itgb3 , Itgb7 , Pik3r3 and Ptk2 were different in miR-29a −/− mice. Immunofluorescence was used to locate genes in the cochlea. Col1a1 , Itga4 and Itgb3 were differentially expressed in the basilar membranes and stria vascularis and spiral ganglion neurons compared to miR-29a +/+ mice. Pik3r3 and Ptk2 were differentially expressed in the basilar membranes and stria vascularis, but not at the s spiral ganglion neurons compared to miR-29a +/+ mice. Our results show that when miR-29a is knocked out, the Col1a1 mediates the focal adhesion pathway may affect the hearing of miR-29a −/− mice. These findings may provide a new direction for effective treatment of age-related hearing loss. • Age-related hearing loss miR-29a mouse model by RNA-seq analysis. • MiR-29a deletion leads to up-regulation of Col1a1 expression, which results in decreased hearing in mice. • Col1a1 is affecting hearing through the focal adhesion pathway. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe and Ni sites were selectively separated by melamine-assisted MOF pyrolysis. • The fluorination process selectively forms FeF 2 rather than NiF 2. • Theoretical and spectral techniques confirmed FeF 2 transformation to active FeOOH. • Enhanced electronic interactions and adsorption energy underscore the impact of fluorination. • Regulation of Fe sites and their synergistic effect with Ni improved catalytic performance. Given its initially low activity and difficulty in active phase formation, Fe site regulation is rarely touched in FeNi-based oxygen evolution reaction (OER) catalysts. Herein, the Fe sites regulation and activity deciphering are demonstrated by selective phase transformation taking nitrogen-doped carbon confined FeNi nanoparticles derived from Fe 2 Ni-MIL-MOF pyrolysis as an example; driven by the reduction atmosphere and Kirkendall effect assisted by melamine pyrolysis, some Fe and Ni sites were separated to form metallic Fe and FeNi alloy and the subsequent fluorination process induced the ionic compound FeF 2 formation rather than NiF 2 , offering a good platform to evaluate the influence of active Fe phase for OER catalysis. Theoretical calculations combined with ex-situ and in-situ spectral characterization techniques proved the complete convention of FeF 2 into a high-valent and reactive intermediate state of FeOOH. Considering the stable metallic state of Ni, the largely improved catalytic performance could be attributed to the Fe site regulation and the subsequent synergistic catalysis effect. Compared to the traditional iron-based catalyst, theoretically, the electronic structure of FeF 2 was more conducive to the active FeOOH phase formation and significantly lowered the reaction energy barrier for OER. By addressing the aforementioned problems, low overpotential and good stability for OER catalysts were realized. The current work showed valid proof of the FeNi-based catalysts regulation via Fe sites for energy-relevant catalysis reactions. [ABSTRACT FROM AUTHOR]

Adopting drought-tolerant (DT) cultivars is an effective strategy to sustain maize (Zea mays L.) production under water shortage. Optimizing plant density is an important management practice for improving maize yield. In a two-year field trial, the response of yield, actual evapotranspiration (ET c act), and water productivity (WP) to plant density (6, 7.5, 9 plants m−2) was assessed under irrigated and rainfed conditions using a DT (ZD958) and a drought-susceptible (DS, ZY309) maize cultivar, and additionally, the comparison of soil water depletion will be conducted among soils growing different DT maize varieties. Under rainfed, average yield, ET c act , and WP were 24.7%, 8.6% and 14.8% greater in ZD958 than ZY309, respectively. When density increased from 6 to 9 plants m−2, for ZD958 and ZY309 ET c act remained relatively constant, whereas their yield and WP first increased and then decreased and ultimately reached their maximum at 7.5 plants m−2. Under irrigation, increasing density (6–9 plants m−2) significantly increased yield and WP for ZD958, but for ZY309, yield and WP were not significantly impacted. Yield across seasons did not differ between cultivars at 6 and 7.5 plants m−2, and ZD958 had a 10.2% yield advantage over ZY309 at 9 plants m−2. The findings imply that DT cultivar showed greater high density tolerance than DS cultivar and thus higher optimal density under irrigation. Under rainfed, both cultivars had similar density tolerance and optimum density, whereas DT cultivar had stronger drought tolerance than DS cultivar, which could explain DT cultivar's greater yield and WP. This study indicate that DT cultivar showed higher and more stable yields than DS cultivar across rainfed and irrigated conditions when grown at optimal densities. Thus, sustainable maize production could be achieved by adopting DT cultivars and optimizing density for different conditions in the study region. • Drought-tolerant cultivar had greater crowding tolerance than drought-susceptible cultivar under irrigation. • Crowding tolerance did not differ between drought-tolerant and drought- susceptible cultivars under rainfed. • Higher tolerance of drought-tolerant cultivar accounts for its higher yield and water productivity under rainfed. • Higher optimum density found in drought-tolerant vs. susceptible cultivar under irrigation but not under rainfed. • Drought-tolerant cultivar extracted more soil water than drought-susceptible cultivar under rainfed. [ABSTRACT FROM AUTHOR]

Metal halide perovskite single crystal (SC) has attracted wide attentions in the field of photoelectric detection. All-inorganic perovskite SCs are much more stable than the hybrid counterparts, but its rapid fabrications usually end up low quality. We proposed a modified solvent-evaporation method that can rapidly obtain smooth and transparent high-quality CsPbBr 3 single crystal with a surface roughness of only 5 nm in a few hours. In this method, the lattice phase of the SC and the growth rate is precisely controlled by the solution temperature, which is raised to the narrow range above the cubic-to-tetragonal phase transition temperature. This precisely controlled solvent temperature allows the CsPbBr 3 SC growing immediately into cubic phase, and limits the volatilization rate of solvent, thus inhibiting the defect density. The SCs grown this way are of high crystallinity, as the half-height width of the (100) and (200) peaks of XRD rocking curve is 0.0154° and 0.0176°, respectively. Characterization of photoelectric properties shows great potential for applications in X-ray detection and photodetection. • CsPbBr 3 single crystals were grown by a modified evaporative solvent method. • The crystal quality is very high crystallinity as the half-height width of the rocking curve as low as 0.0176°. • The effect of growth temperature on crystal quality is investigated. • The growth time of large size (3 mm) CsPbBr 3 single crystals is reduced to 10 h. [ABSTRACT FROM AUTHOR]

Support engineering modulated Pt by hierarchical MoSe 2 @mesoporous hollow carbon support well addressed the challenges in low intrinsic activity and easy poisoning problems during methanol electrolysis. [Display omitted] • Electrochemical energy conversion from methanol to hydrogen via methanol electrolysis. • Support engineering modulated Pt by hierarchical MoSe 2 @mesoporous hollow carbon support. • Strong interaction and coupling ability between Pt and MoSe 2 regulated the active centers. • Weakened binding strength of CO ad and H ad intermediates during catalysis. • High electrochemical properties due to enhanced oxophilicity and poisoning tolerance ability. Hydrogen generation from methanol via methanol-assisted water splitting is a promising electrochemical energy conversion technology but still meets challenges in addressing the low intrinsic activity and easy poisoning problems of the conventional Pt catalysts. Herein, the support engineering modulated Pt by hierarchical MoSe 2 @mesoporous hollow carbon support was proposed to integrate some structural and catalytic advantages for hydrogen evolution reaction (HER) and methanol oxidation reaction (MOR). Supporting engineering by layered MoSe 2 nanosheets confined in mesoporous hollow carbon spheres (MHCSs) is adopted to uniformly anchor Pt nanoparticles (Pt/MoSe 2 @MHCS), which effectively enhances the conductivity and prevents the layer-by-layer stacking of MoSe 2 ; Strong interaction and coupling ability between Pt and MoSe 2 and the resultant electronic structure regulation of the active centers could weaken the binding strength of CO* and H* intermediates during catalysis and strengthen the oxophilicity leading to improved MOR and HER kinetics. Specifically, Pt/MoSe 2 @MHCS shows a significantly improved MOR current density of 81.1 mA cm−2, about 3.0 times that of the benchmark Pt/C catalyst. Meanwhile, it also exhibits the HER performance of 28 mV to achieve a kinetic current density of 10 mA cm−2 in methanol-contained electrolytes. When employed for overall methanol electrolysis, a lowered input voltage of 1.11 V can be obtained to drive the current density (10 mA cm−2) compared to that for water electrolysis (0.62 V vs. 1.73 V). The electrochemical properties of high activity, rapid catalytic kinetics, and good stability were also demonstrated due to the enhanced oxophilicity and high poisoning tolerance ability resulting from the MoSe 2 /carbon substrate-induced electron redistribution of Pt sites. This work reports a novel platform to address the catalysis challenges in hydrogen production via the methanol electrolysis technique. [ABSTRACT FROM AUTHOR]