The development of advanced and efficient anode catalysts to accelerate the kinetic rate of methanol oxidation plays an important role in the large-scale commercial application of the direct methanol ...fuel cells (DMFCs). Herein, we report the design and construction of small-sized rhodium nanocrystals decorated on 3D hybrid aerogels built from graphene and metal-organic framework (Rh/G-ZIF) via a solvothermal co-assembly method. Benefiting from the 3D rigid crosslinked architecture, abundant porous channels, and highly dispersed ultrafine Rh nanoparticles, the optimized Rh/G-ZIF aerogel exhibits a large electrochemically active surface area, high mass and specific activities, and excellent long-term durability toward the methanol electrooxidation, all of which are significantly superior to those of Rh catalysts supported by traditional carbon materials (such as carbon black, carbon nanotube, and graphene).
A bottom-up strategy is adopt to construct a 3D nanoarchitecture consisting of ultrafine Rh nanoparticles strongly coupled with MOF-modified graphene networks via a self-assembly process, which demonstrates exceptional electrocatalytic capability toward methanol oxidation. Display omitted
•Ultrafine Rh nanoparticles are first grown on 3D ZIF-modified graphene frameworks.•The unique architectural design endows the catalyst with plenty of catalytically active sites.•The optimized catalyst shows exceptional electrocatalytic activity for methanol oxidation.
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•The sources and types of calf rennet substitutes were comprehensively summarized.•The advantages and disadvantages of different calf rennet substitutes were ...discussed.•Characteristics and modification of microbial milk-clotting enzymes were elaborated.•The influence of calf rennet substitutes on cheese quality was summarized.•Future perspective and challenges of calf rennet substitutes were proposed.
Milk coagulation is an important step in cheese production, and milk-clotting enzymes (MCEs) play a major role in this process. Calf rennet is the most widely used MCE in the cheese industry. The use of calf rennet substitutes is becoming necessary due to the limited availability of calf rennet and the increase in cheese consumption. The objective of this review is to summarize the latest findings on calf rennet substitutes (animal MCEs, plant-derived MCEs, recombinant MCEs and microbial MCEs) and their application in cheese production. Special emphasis has been placed on aspects of the effects of these substitutes on hydrolysis, functional peptides, cheese variety and cheese yield. The advantages and disadvantages of different calf rennet substitutes are discussed, in which microbial MCEs have the advantages of less expensive production, greater biochemical diversity, easier genetic modification, etc. In particular, some of these MCEs have suitable characteristics for cheese production and are considered to be the most potential calf rennet substitutes. Moreover, challenges and future perspectives are presented to provide inspiration for the development of excellent calf rennet substitutes.
Aim： Voltage-gated sodium channels composed of a pore-forming a subunit and auxiliary 13 subunits are responsible for the upstroke of the action potential in cardiac myocytes. The pore-forming ...subunit of the cardiac sodium channel Nav1.5, which is encoded by SCNSA, is the main ion channel that conducts the voltage-gated cardiac sodium current （INa） in cardiac cells. The current study sought to investigate the inhibitory effects of hesperetin on human cardiac Nav1.5 channels stably expressed in human embryonic kidney 293 （HEK 293） cells and on the voltage-gated cardiac sodium current （INa） in human atrial myocytes. Methods： The effects of hesperetin on human cardiac Nav1.5 channels expressed in HEK 293 cells and on cardiac Na＋ currents in human atrial myocytes were examined through whole-cell patch-clamp techniques. Results： Nav1.5 currents were potently and reversibly suppressed in a concentration- and voltage-dependent manner by hesperetin, which exhibited an IC50 of 62.99 pmol/L. Hesperetin significantly and negatively shifted the voltage-dependent activation and inactivation curves. Hesperetin also markedly decelerated Navl.5 current inactivation and slowed the recovery from Nav1.5 channel inactivation. The hesperetin-dependent blockage of Navl.5 currents was frequency-dependent. Hesperetin also potently and reversibly inhibited Na＋ current （INa） in human atrial myocytes, consistently with its effects on Nav1.5 currents in HEK 293 cells. Conclusion： Hesperetin is a potent inhibitor of INa in human atrial myocytes and Nav1.5 channels expressed in human embryonic kidney 293 cells. Hesperetin probably functions by blocking the open state and the inactivated state of these channels.
5-Hydroxymethylcytosine （5hmC） is an important mammalian DNA epigenetic modification that has been linked to gene regulation and cancer pathogenesis. Here we explored the diagnostic potential of 5hmC ...in circulating cell-free DNA （cfDNA） using a sensitive chemical labeling-based low-input shotgun sequencing approach. We sequenced cell- free 5hmC from 49 patients of seven different cancer types and found distinct features that could be used to predict cancer types and stages with high accuracy. Specifically, we discovered that lung cancer leads to a progressive global loss of 5hmC in cfDNA, whereas hepatocellular carcinoma and pancreatic cancer lead to disease-specific changes in the cell-free hydroxymethylome. Our proof-of-principle results suggest that cell-free 5hmC signatures may potentially be used not only to identify cancer types but also to track tumor stage in some cancers.
In this study, the control effects of synthetic microbial communities composed of peanut seed bacteria against seed aflatoxin contamination caused by Aspergillus flavus and root rot by Fusarium ...oxysporum were evaluated.
Potentially conserved microbial synthetic communities (C), growth-promoting synthetic communities (S), and combined synthetic communities (CS) of peanut seeds were constructed after 16S rRNA Illumina sequencing, strain isolation, and measurement of plant growth promotion indicators. Three synthetic communities showed resistance to root rot and CS had the best effect after inoculating into peanut seedlings. This was achieved by increased defense enzyme activity and activated salicylic acid (SA)-related, systematically induced resistance in peanuts. In addition, CS also inhibited the reproduction of A. flavus on peanut seeds and the production of aflatoxin. These effects are related to bacterial degradation of toxins and destruction of mycelia.
Inoculation with a synthetic community composed of seed bacteria can help host peanuts resist the invasion of seeds by A. flavus and seedlings by F. oxysporum and promote the growth of peanut seedlings.
Drought dramatically affects plant growth and yield. A previous study indicated that endophytic fungus Phomopsis liquidambaris can improve the drought resistance of peanuts, which is related with the ...root arbuscular mycorrhizal fungi (AMF) community; however, how root endophytes mediate AMF assembly to affect plant drought resistance remains unclear. Here, we explored the mechanism by which endophytic fungus recruits AMF symbiotic partners via rhizodeposits to improve host drought resistance. The results showed that Ph. liquidambaris enhanced peanut drought resistance by enriching the AMF genus Claroideoglomus of the rhizosphere. Furthermore, metabolomic analysis indicated that Ph. liquidambaris significantly promoted isoformononetin and salicylic acid (SA) synthesis in rhizodeposits, which were correlated with the increase in Claroideoglomus abundance following Ph. liquidambaris inoculation. Coinoculation experiments confirmed that isoformononetin and SA could enrich Claroideoglomus etunicatum in the rhizosphere, thereby improving the drought resistance. This study highlights the crucial role of fungal consortia in plant stress resistance.Drought dramatically affects plant growth and yield. A previous study indicated that endophytic fungus Phomopsis liquidambaris can improve the drought resistance of peanuts, which is related with the root arbuscular mycorrhizal fungi (AMF) community; however, how root endophytes mediate AMF assembly to affect plant drought resistance remains unclear. Here, we explored the mechanism by which endophytic fungus recruits AMF symbiotic partners via rhizodeposits to improve host drought resistance. The results showed that Ph. liquidambaris enhanced peanut drought resistance by enriching the AMF genus Claroideoglomus of the rhizosphere. Furthermore, metabolomic analysis indicated that Ph. liquidambaris significantly promoted isoformononetin and salicylic acid (SA) synthesis in rhizodeposits, which were correlated with the increase in Claroideoglomus abundance following Ph. liquidambaris inoculation. Coinoculation experiments confirmed that isoformononetin and SA could enrich Claroideoglomus etunicatum in the rhizosphere, thereby improving the drought resistance. This study highlights the crucial role of fungal consortia in plant stress resistance.
NiAl-layered double hydroxide（NiAl-LDH） networks loaded carbon microcylinder（CMC） hybrid was synthesized for the first time using typical carbon based microelectromechanical systems（C-MEMS）techniques ...combined with in situ growth progress. The incorporation of NiAl-LDH on C-MEMS structures via a simple pyrolysis of modified photoresist was investigated. With proper control of parameters in lithography and hydrothermal processes, the NiAl-LDH/CMC composites with suitable morphology were fabricated. When the composites applied as new catalytic material for glucose detection, this simple sensor showed satisfying electrocatalytic properties towards glucose oxidation owing to its unique structure and excellent electric conductivity. It is also worth pointing out that this novel fabrication process can equip carbon microfeatures with various nanostructures, and have wide potential applications in scaling up carbon based nanocomposites.
Background： Morphological changes of the vasculature system in patients with myopia have been observed by Doppler ultrasound and fundus fluorescein angiography （FFA）; however, these studies have ...limitations. Doppler ultrasound provides low-resolution images which are mainly obtained from visualized large vessels, and FFA is an invasive examination. Optic coherence tomography （OCT） angiography is a noninvasive, high-resolution measurement for vascular density. The purpose of this study was to investigate the change of vascular density in myopic eyes using OCT angiography. Methods： This cross-sectional study includes a total of 91 eyes ~Yom 47 participants including control, moderate, and high myopia that were evaluated by OCT angiography. Patients with myopia were recruited from the Refractive Department, Shenzhen Aier Eye Hospital, from August 5, 2015 to April 1, 2016. Emmetropic eyes were from healthy volunteers. The vascular density at macula and optic disc regions, ganglion cell complex （GCC） thickness, and retinal nerve fiber layer （RNFL） thickness were measured. Their relationships with axial length （AL） and refractive error were analyzed. One-way analysis of variance （ANOVA）, Pearson＇s correlation, and generalized estimating equation were used for statistical analysis, Results： Both superficial and deep macular vascular density were highest in control （25.64% ± 3.76% and 37.12% ± 3.66%, respectively）, then in moderate myopia （21.15% ± 5.33% and 35.35% ± 5.50%, respectively）, and lowest in high myopia group （ 19.64% ± 3.87% and 32.81% ± 6.29%, respectively） （F =13.74 and 4.57, respectively; both P 〈 0.001）. Both superficial （β = -0.850 and 0.460, respectively） and deep （β = -0.766 and 0.396, respectively） macular vascular density were associated with AL and spherical equivalent （all P 〈 0.001 ）. Superficial macular vascular density was associated with GCC thickness （β = 0.244, P = 0.040）, independent of spherical equivalent. The vascular density in optic disc region had no difference among the three groups, and it was not associated with AL, spherical equivalent, or RNFL thickness. Conclusion： Our results suggested that with the increase of myopia, the vascular density decreased in macular region, but not in optic disc region.
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