The incineration and burying of the soiled bedding of laboratory animals, as well as using detergents to treat their feces, is hazardous to the environment. This highlights the need for an ...alternative, environmentally friendly solution for the treatment of the waste of laboratory animal facilities. This study aims to evaluate the efficacy of ozone disinfection of the soiled bedding and feces of laboratory animals.
Two grams of soiled beddings were randomly sampled from the cages of mice and rats. These samples were mixed in a beaker with 40ml saline. Ozone was piped into the beaker at a concentration of 500mg/h. Samples were taken from the beaker at time 0min, 30min, 45min and 60min after ozone treatment for microbiological culturing in an incubator for 48h. Colony form unit of each plate (CFU/plate) at each time point were counted, the mean CFU/plate at each time point after ozone treatment were compared with that present at time zero. Feces of rabbits and dogs were treated and pathogens were counted the similar way as that of bedding of the mice and rats; samples being taken at 0min, 15min, 30min, 45min and 60min.
Pathogens were observed in beddings of both mice and rats as well as in feces of rabbits and dogs. Ozone treatment for 30min killed more than 93% of pathogens in the bedding of the two rodent species and 60min of treatment killed over 99% of pathogens. Treatment of rabbit and dog feces for 30min killed over 96% pathogens present, and 60min's treatment killed nearly all the pathogens. Both Gram positive and Gram negative pathogens were sensitive to ozone treatment.
Ozone treatment of bedding and feces is an effective and environment friendly way to deal with the waste of animal facilities, saving energy and potentially enabling their reuse as fertilizer.
The large‐scale production of metal–air batteries, an appealing solution for next‐generation energy storage, requires low‐cost, earth‐abundant, and efficient oxygen electrode materials, yet insights ...into active catalyst structures and synergistic reactivity remain largely unknown. Here, a new bifunctional oxygen electrode based on nitrogen‐doped carbon nanotubes decorated by spinel CuCo2O4 quantum dots (CuCo2O4/N‐CNTs) is reported, outperforming the benchmark of state‐of‐the‐art noble metal catalysts. Combining spectroscopic characterization and electrochemical studies, a prominent synergetic effect between CuCo2O4 and N‐doped carbon nanotubes is uncovered: the high conductivity, large active surface area, and increase in the number of catalytic sites induced by Cu doping (i.e., Cu2+ and CuN) can be beneficial to the overall electrocatalytic activities. Remarkably, the native flexibility of CuCo2O4/N‐CNTs allows its direct use as reversible oxygen electrodes in Zn–air batteries either with liquid alkaline electrolyte or in the all‐solid‐state configuration. The prepared devices demonstrate excellent discharging/charging performance, large energy density (83.83 mW cm−2 in liquid state, 1.86 W g−1 in all‐solid‐state), and long lifetime (48 h in liquid state, 9 h in all‐solid‐state), holding great promise in the practical application of rechargeable metal–air batteries and other fuel cells.
Advanced Cu Co bimetallic oxide quantum dots are decorated on nitrogen‐doped carbon nanotubes to serve as the bifunctional oxygen catalyst. A strong synergetic coupling in CuCo2O4/N‐CNTs is proposed, which provides advantaged local chemical environment and enriched catalytic sites. Benefiting from these features, CuCo2O4/N‐CNTs with reversible oxygen catalytic activity is capable of operating the new‐generation rechargeable zinc–air batteries.
It is well accepted that the microwave absorption performance (MAP) of carbon nanotubes (CNTs) can be enhanced via coating magnetic nanoparticles on their surfaces. However, it is still unclear if ...the magnetic coating structure has a significant influence on the microwave absorption behavior. In this work, nano-Fe3O4 compact-coated CNTs (FCCs) and Fe3O4 loose-coated CNTs (FLCs) are prepared using a simple solvothermal method. The MAP of the Fe3O4-coated CNTs is shown to be adjustable via controlling the Fe3O4 nanocoating structure. The results reveal that the overall MAP of coated CNTs strongly depends on the magnetic coating structure. In addition, the FCCs show a much better MAP than the FLCs. It is shown that the microwave absorption difference between the FLCs and FCCs is due to the disparate complementarities between the dielectric loss and the magnetic loss, which are related to the coverage density of Fe3O4 nanoparticles on the surfaces of CNTs. For FCCs, the mass ratio of CNTs to Fe3+ is then optimized to maximize the effective complementarities between the dielectric loss and the magnetic loss. Finally, a comparison is made with the literature on Fe3O4-carbon-based composites. The FCCs at the optimized CNT to Fe3+ ratio in the present work show the most effective specific RLmin (28.7 dB·mm–1) and the widest effective bandwidth (RL < −10 dB) (8.3 GHz). The excellent MAP of the as-prepared FCC sample is demonstrated to result from the consequent dielectric relaxation process and the improved magnetic loss. Consequently, the structure–property relationship revealed is significant for the design and preparation of CNT-based materials with effective microwave absorption.
Considering the nuclear fuel reprocessing conditions at 75 °C and the oxidizability of iodine, thermal and chemical stabilities are especially important for porous materials to enrich iodine. ...However, most organic or metal coordinated porous materials hardly meet this long‐term demand. Here, highly porous carbon is prepared from pyrolysis at high temperature using triptycene‐based hypercrosslinked polymer as precursor, and possesses high Brunauer–Emmett–Teller (BET) surface area of 3125 m2 g−1 and pore volume of 1.60 cm3 g−1, and exhibits excellent iodine uptake ability of 340 wt% at 75 °C. Moreover, the obtained hyperporous carbon also displays remarkable capture efficiency of iodine from water with the maximum adsorption capacity of 926 mg g−1. With the characteristics of easy preparation and good chemical and thermal stabilities, the hyperporous carbon may be an ideal adsorbent in iodine capture.
Hyperporous carbon from triptycene‐based hypercrosslinked porous polymer exhibits excellent iodine capture and gas storage.
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•Green antibacterial nanocomposites were obtained by adding CNC-ZnO nanohybrids into PHBV.•CNC-ZnO induce great improvements on mechanical, barrier and antibacterial properties of ...PHBV.•In vitro biodegradation of PHBV can be tailored by introducing various CNC-ZnO contents.•Possible mechanism for PHBV hydrolytic degradation with/without CNC-ZnO is presented.
Fabrication and characterization of bbiodegradable nanocomposites based on poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) matrix reinforced with cellulose nanocrystal (CNC)-ZnO nanohybrids via simple solution casting for possible use as antibacterial biomedical materials is reported. The obtained nanocomposites exhibited an excellent antibacterial ratio of 95.2–100% for both types of bacteria namely S. aureus and E. coli and showed 9–15% degradation after one week. The addition of CNC-ZnO showed a positive effect on hydrophilicity and barrier properties. More significantly, the nanocomposites with 10wt% CNC-ZnO showed enhancement in tensile strength (140.2%), Young’s modulus (183.1%), and the maximum decomposition temperature (Tmax) value increased by 26.1°C. Moreover, this study has provided a possible mechanism for using such nanofillers on the hydrolytic degradation of PHBV, which was beneficial to obtain the high-performance nanocomposites with modulated degradation rate for antibacterial biomaterials.
The use of formic acid (FA) to produce molecular H2 is a promising means of efficient energy storage in a fuel‐cell‐based hydrogen economy. To date, there has been a lack of heterogeneous catalyst ...systems that are sufficiently active, selective, and stable for clean H2 production by FA decomposition at room temperature. For the first time, we report that flexible pyridinic‐N‐doped carbon hybrids as support materials can significantly boost the efficiency of palladium nanoparticle for H2 generation; this is due to prominent surface electronic modulation. Under mild conditions, the optimized engineered Pd/CN0.25 catalyst exhibited high performance in both FA dehydrogenation (achieving almost full conversion, and a turnover frequency of 5530 h−1 at 25 °C) and the reversible process of CO2 hydrogenation into FA. This system can lead to a full carbon‐neutral energy cycle.
Pyridinic‐N‐tuned catalysis: An electron‐rich pyridinic‐N dopant modulates the electronic interactions between the active sites of palladium nanoparticles and the carbon support. Formic acid dehydrogenation at room temperature is significantly boosted by the pyridinic‐N‐doped palladium catalyst, presenting an efficient and reliable route to clean H2 generation and sustainable energy storage.
How two subgenomes in allo-tetraploids adapt to coexistence and coordinate through structure and expression evolution requires extensive studies. In the present study, we report an improved genome ...assembly of allo-tetraploid common carp, an updated genome annotation of allo-tetraploid goldfish and the chromosome-scale assemblies of a progenitor-like diploid Puntius tetrazona and an outgroup diploid Paracanthobrama guichenoti. Parallel subgenome structure evolution in the allo-tetraploids was featured with equivalent chromosome components, higher protein identities, similar transposon divergence and contents, homoeologous exchanges, better synteny level, strong sequence compensation and symmetric purifying selection. Furthermore, we observed subgenome expression divergence processes in the allo-tetraploids, including inter-/intrasubgenome trans-splicing events, expression dominance, decreased expression levels, dosage compensation, stronger expression correlation, dynamic functionalization and balancing of differential expression. The potential disorders introduced by different progenitors in the allo-tetraploids were hypothesized to be alleviated by increasing structural homogeneity and performing versatile expression processes. Resequencing three common carp strains revealed two major ecotypes and uncovered candidate genes relevant to growth and survival rate.
Diabetic cognitive impairment (DCI) is a serious neurodegenerative disorder caused by diabetes, with chronic inflammation being a crucial factor in its pathogenesis. Pterostilbene is a well‐known ...natural stilbene derivative that has excellent anti‐inflammatory activity, suggesting its potential medicinal advantages for treating DCI. Therefore, this study is to explore the beneficial effects of pterostilbene for improving cognitive dysfunction in DCI mice. A diabetic model was induced by a high‐fat diet plus streptozotocin (40 mg·kg−1) for consecutive 5 days. After the animals were confirmed to be in a diabetic state, they were treated with pterostilbene (20 or 60 mg·kg−1, i.g.) for 10 weeks. Pharmacological evaluation showed pterostilbene could ameliorate cognitive dysfunction, regulate glycolipid metabolism disorders, improve neuronal damage, and reduce the accumulation of β‐amyloid in DCI mice. Pterostilbene alleviated neuroinflammation by suppressing oxidative stress and carbonyl stress damage, astrocyte and microglia activation, and dopaminergic neuronal loss. Further investigations showed that pterostilbene reduced the level of lipopolysaccharide, modulated colon and brain TLR4/NF‐κB signaling pathways, and decreased the release of inflammatory factors, which in turn inhibited intestinal inflammation and neuroinflammation. Furthermore, pterostilbene could also improve the homeostasis of intestinal microbiota, increase the levels of short‐chain fatty acids and their receptors, and suppress the loss of intestinal tight junction proteins. In addition, the results of plasma non‐targeted metabolomics revealed that pterostilbene could modulate differential metabolites and metabolic pathways associated with inflammation, thereby suppressing systemic inflammation in DCI mice. Collectively, our study found for the first time that pterostilbene could alleviate diabetic cognitive dysfunction by inhibiting the TLR4/NF‐κB pathway through the microbiota‐gut‐brain axis, which may be one of the potential mechanisms for its neuroprotective effects.
Pterostilbene could alleviate diabetic cognitive impairment by inhibiting the TLR4/NF‐κB pathway through the microbiota‐gut‐brain axis.
Bone metastases occur in most advanced breast cancer patients and cause serious skeletal-related complications. The mechanisms by which bone metastasis seeds develop in primary tumors and ...specifically colonize the bone remain to be elucidated. Here, we show that forkhead box F2 (FOXF2) functions as a master transcription factor for reprogramming cancer cells into an osteomimetic phenotype by pleiotropic transactivation of the BMP4/SMAD1 signaling pathway and bone-related genes that are expressed at early stages of bone differentiation. The epithelial-to-osteomimicry transition regulated by FOXF2 confers a tendency on cancer cells to metastasize to bone which leads to osteolytic bone lesions. The BMP antagonist Noggin significantly inhibits FOXF2-driven osteolytic bone metastasis of breast cancer cells. Thus, targeting the FOXF2-BMP/SMAD axis might be a promising therapeutic strategy to manage bone metastasis. The role of FOXF2 in transactivating bone-related genes implies a biological function of FOXF2 in regulating bone development and remodeling.
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