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Volatile organic compounds (VOCs) severely threaten human health and the ecological environment because most of them are toxic, mutagenic, and carcinogenic. The persistent increase of ...VOCs together with the stringent regulations make the reduction of VOC emissions more imperative. Up to now, numerous VOC treatment technologies have emerged, such as incineration, condensation, biological degradation, absorption, adsorption, and catalysis oxidation et al. Among them, the adsorption technology has been recognized as an efficient and economical control strategy because it has the potential to recover and reuse both adsorbent and adsorbate. Due to their large specific surface area, rich porous structure, and high adsorption capacity, carbonaceous adsorbents are widely used in gas purification, especially with respect to VOC treatment and recovery. This review discusses recent research developments of VOC adsorption onto a variety of engineered carbonaceous adsorbents, including activated carbon, biochar, activated carbon fiber, carbon nanotube, graphene and its derivatives, carbon-silica composites, ordered mesoporous carbon, etc. The key factors influence the VOC adsorption are analyzed with focuses on the physiochemical characters of adsorbents, properties of adsorbates as well as the adsorption conditions. In addition, the sources, health effect, and abatement methods of VOCs are also described.
Biochar is a promising agent for wastewater treatment, soil remediation, and gas storage and separation. This review summarizes recent research development on biochar production and applications with ...a focus on the application of biochar technology in wastewater treatment. Different technologies for biochar production, with an emphasis on pre-treatment of feedstock and post treatment, are succinctly summarized. Biochar has been extensively used as an adsorbent to remove toxic metals, organic pollutants, and nutrients from wastewater. Compared to pristine biochar, engineered/designer biochar generally has larger surface area, stronger adsorption capacity, or more abundant surface functional groups (SFG), which represents a new type of carbon material with great application prospects in various wastewater treatments. As the first of its kind, this critical review emphasizes the promising prospects of biochar technology in the treatment of various wastewater including industrial wastewater (dye, battery manufacture, and dairy wastewater), municipal wastewater, agricultural wastewater, and stormwater. Future research on engineered/designer biochar production and its field-scale application is discussed. Based on the review, it can be concluded that biochar technology represents a new, cost effective, and environmentally-friendly solution for the treatment of wastewater.
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•Biochar technologies in various wastewater treatment are elucidated.•Feedstock pre-treatment and post-treatment effect on biochar production is reviewed.•Biochar as an innovative adsorbent to remove aqueous contaminants is discussed.•Future perspectives of biochar technology in wastewater treatment are summarized.
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•VOC sorption capacities of biochars were between 5.58 and 91.16mgg−1.•VOC removal was strongly affected by biochar’s surface area.•VOC removal was strongly affected by biochar’s ...noncarbonized organic matter content.•Physical adsorption and partitioning were the governing mechanisms.
Sorption is one of the most efficient and low cost strategies for volatile organic compound (VOC) removal, but VOC sorption by biochar has seen limited research. In this work, gas phase sorption experiments were conducted to determine the sorption potential and mechanisms of VOCs onto biochar. A total of 15 biochars produced from 5 common feedstocks at 300, 450, and 600°C were evaluated as sorbents. Three common VOCs (acetone, cyclohexane, and toluene) were chosen as sorbates. The results showed that all the tested biochars had VOC sorption capacity in the range of 5.58–91.2mgg−1. The sorption capacities were mainly influenced by both the surface area of biochar and its noncarbonized organic matter content. The vapor sorption process was exothermic, and the removal of VOCs by the biochars decreased with increasing feedstock temperature. Both the physical adsorption and partition mechanisms played important roles in controlling the VOC removal by the biochars. Biochar maintained its VOC removal ability after five consecutive sorption-desorption cycles, which indicated good reusability. Findings of this work suggest that biochar is a promising alternative sorbent for gaseous VOC removal.
The ongoing pandemic of coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Neutralizing antibodies against SARS-CoV-2 are an option for ...drug development for treating COVID-19. Here, we report the identification and characterization of two groups of mouse neutralizing monoclonal antibodies (MAbs) targeting the receptor-binding domain (RBD) on the SARS-CoV-2 spike (S) protein. MAbs 2H2 and 3C1, representing the two antibody groups, respectively, bind distinct epitopes and are compatible in formulating a noncompeting antibody cocktail. A humanized version of the 2H2/3C1 cocktail is found to potently neutralize authentic SARS-CoV-2 infection in vitro with half inhibitory concentration (IC50) of 12 ng/mL and effectively treat SARS-CoV-2-infected mice even when administered at as late as 24 h post-infection. We determine an ensemble of cryo-EM structures of 2H2 or 3C1 Fab in complex with the S trimer up to 3.8 Å resolution, revealing the conformational space of the antigen-antibody complexes and MAb-triggered stepwise allosteric rearrangements of the S trimer, delineating a previously uncharacterized dynamic process of coordinated binding of neutralizing antibodies to the trimeric S protein. Our findings provide important information for the development of MAb-based drugs for preventing and treating SARS-CoV-2 infections.
Sorghum has been widely used for liquor production and brewing, but how to make efficiently utilize sorghum straw (SS) has become an urgent problem. Meanwhile, the wastewater produced by winemaking ...is typical organic wastewater with a high ammonium concentration. To solve the problem of resource utilization of SS and remove ammonium from water, SS was used to prepare biochar as an adsorbent for ammonium adsorption. Batch adsorption experiments were carried out to study the influencing factors and adsorption mechanisms of ammonium onto sorghum straw biochar (SSB). The results showed that the adsorption capacity of SSB was much higher than that of SS. The SSB pyrolyzed at 300 °C had the highest adsorption capacity. The favorable pH was 6-10, and the optimal dosage was 2.5 g/L. The adsorption process and behavior conformed to the pseudo-second-order kinetic and Langmuir isotherm adsorption models. The maximum ammonium adsorption capacity of SSB at 45 °C was 7.09 mg/g, which was equivalent to 7.60 times of SS. The ammonium adsorption of SS and SSB was mainly chemical adsorption. The regeneration test indicated that SSB had good regeneration performance after three adsorption-regeneration cycles. This work suggests that SSB could be potentially applied to sewage treatment containing ammonium to achieve the purpose of resource recycling.
Currently one-third of the proteins encoded by the Arabidopsis (
) genome are of unknown function. Some of these unknown proteins are likely to be involved in uncharacterized vital biological ...processes. Evolutionarily conserved single copy genes in flowering plants have been shown to be enriched in essential housekeeping functions. This together with publicly available gene expression data allows for a focused search for uncharacterized essential genes. Here we identify an essential single copy gene called
(
) in Arabidopsis. We show that
is predominantly expressed in actively dividing cells and performs essential functions in seed development and root meristem maintenance. Cell cycle tracking using 5-ethynyl-2'-deoxyuridine staining and fluorescent cell cycle markers together with the increased size of nucleolus and nucleus in
mutants indicate that
is required for cell cycle progression through the S or G2 phases. Intriguingly, OPNR localizes to the nuclear envelope and mitochondria. Furthermore, the nuclear envelope localization of OPNR is dependent on its interaction with nuclear inner membrane Sad1/UNC-84 (SUN) domain proteins SUN1 and SUN2. Taken together our results open a line of investigation into an evolutionarily conserved essential cellular process occurring in both the nuclear envelopes and mitochondria of dividing cells.
In this study, we propose to synthesize NPs using plant extract containing active biomedical components, with the goal of obtaining NPs that inherit the biomedical activities of the plant. Herein, we ...report the synthesis of manganese dioxide nanoparticles (VBLE-MnO
2
NPs) using the leaves extract of
Viola betonicifolia
, in which the biological active plant’s secondary metabolites function as both reducing and capping agents. The synthesized NPs were successfully characterized with different spectroscopic techniques. The antibacterial, antifungal, and biofilm inhibition properties of the synthesized VBLE-MnO
2
NPs were further explored against a variety of bacteria (Gram-positive and Gram-negative) and mycological species. Additionally, their antioxidant ability against linoleic acid peroxidation inhibition, cytobiocompatibility with hMSC cells, and cytotoxicity against MCF-7 cells were investigated compared to leaves extract and chemically synthesized manganese dioxide NPs (CH-MnO
2
NPs). The results were demonstrated that the synthesized VBLE-MnO
2
NPs presented excellent antibacterial, antifungal, and biofilm inhibition performance against all the tested microbial species compared to plant leaves extract and CH-MnO
2
NPs. Moreover, they also exhibited significant antioxidant potential, which was comparable to the external standard (ascorbic acid); however, it was higher than plant leaves extract and CH-MnO
2
NPs. Furthermore, the synthesized CH-MnO
2
NPs displayed good cytobiocompatibility with hMSC cells compared to CH-MnO
2
NPs. The enhanced antioxidant, antibacterial, antifungal, and biofilm inhibition efficacy as compared to CH-MnO
2
NPs might be attributed to the synergistic effect of the VBLE-MnO
2
NPs’ physical properties and the adsorbed biologically active phytomolecules from the leaves extract of
V. betonicifolia
on their surface. Thus, our study establishes a novel ecologically acceptable route for nanomaterials’ fabrication with increased and/or extra medicinal functions derived from their herbal origins.
Enterovirus D68 (EV-D68) is an emerging pathogen associated with respiratory diseases and/or acute flaccid myelitis. Here, two MAbs, 2H12 and 8F12, raised against EV-D68 virus-like particle (VLP), ...show distinct preference in binding VLP and virion and in neutralizing different EV-D68 strains. A combination of 2H12 and 8F12 exhibits balanced and potent neutralization effects and confers broader protection in mice than single MAbs when given at onset of symptoms. Cryo-EM structures of EV-D68 virion complexed with 2H12 or 8F12 show that both antibodies bind to the canyon region of the virion, creating steric hindrance for sialic acid receptor binding. Additionally, 2H12 binding can impair virion integrity and trigger premature viral uncoating. We also capture an uncoating intermediate induced by 2H12 binding, not previously described for picornaviruses. Our study elucidates the structural basis and neutralizing mechanisms of the 2H12 and 8F12 MAbs and supports further development of the 2H12/8F12 cocktail as a broad-spectrum therapeutic agent against EV-D68 infections in humans.
Abstract
Tropical cyclones (TCs) can influence climate by pumping heat into the ocean, yet little is known about how the TC-induced ocean heat uptake (OHU) has changed in recent decades. Based on ...ocean reanalysis, we calculated OHU and found a significant decline of TC-induced OHU from 1982 to 2018. If all the ocean heat gain is balanced by poleward heat transport, approximately 15% of peak ocean heat transport would have been reduced during the study period. The decreasing trend of OHU is consistent with the enhanced ocean stratification, the shallowed mixed layer depth and the reduced cold wake size. The reduction of OHU primarily occurs in the Northwest Pacific, where the shortened TC lifespan contributes as well. Furthermore, the decline of OHU might offset about 28% of the upper ocean warming in the subtropical Northwest Pacific.
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