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Domestic sewage tailwater (DSTW) reuse for crop irrigation is considered a promising practice to reduce water demand, mitigate water pollution, and substitute chemical fertilization. The level of the above environmental benefits of this water reuse strategy, especially when applied to paddy wetlands, remains unclear. In this study, soil column experiments were conducted to investigate the nitrogen and phosphorus fate in paddy wetlands subjected to different tailwater irrigation and drainage strategies, specifically, (i) TW1 and TW2 for regular or enhanced irrigation-drainage without N fertilization, (ii) TW3 and TW4 for regular irrigation with base or tillering N fertilizer, (iii) conventional fertilization N210, and (iv) no-fertilization controls N0. The results showed that the total nitrogen (TN), nitrate (NO3−), and total phosphorus (TP) removal rates from the paddies irrigated by DSTW ranged between 51.92 and 59.34%, 68.1 and 83.42%, and 85.69 and 86.98% respectively. Ammonia emissions from the DSTW-irrigated treatments were reduced by 14.6~47.2% compared to those paddies subjected to conventional fertilization (N210), similarly for TN emissions, with the exception of the TW2 treatment. Overall, it is established that the paddy wetland could effectively remove residual N and P from surface water runoffs, while the partial substitution of chemical fertilization by DSTW could be confirmed. The outcome of this study demonstrates that DSTW irrigation is a promising strategy for sustainable rice production with a minimized environmental impact. [ABSTRACT FROM AUTHOR]

Evidence for microbial biodegradation of polyethylene terephthalate (PET) has been reported, but little is known about the PET biodegradation process and molecular mechanism by marine microorganisms. Here, we show the biodegradation of PET by the membrane-anchored PET esterase from the marine bacterium Rhodococcus pyridinivorans P23, elucidate the properties of this enzyme, and propose the PET biodegradation by this strain in biofilm. We identify the PET-degrading enzyme dubbed PET esterase through activity tracking. In addition to depolymerizing PET, it hydrolyzes MHET into TPA under acid conditions. We prove that it is a low and constitutively transcribed, membrane-anchored protein displayed on the cell surface. Furthermore, we also investigate the microbial groups possessing PET esterase coupled with the TPA degradation pathway, mainly in the phyla Proteobacteria and Actinobacteriota. Clarification of the microbial PET biodegradation in the marine environment will contribute to the understanding of bioremediation of marine PET pollution. A PET-degrading bacterium forming biofilms on PET surfaces was isolated from marine deep-sea sediment. The PET esterase localized at the cell surface was constitutively produced and also slowly degrading MHET to TPA under acidic conditions. [ABSTRACT FROM AUTHOR]

Acidic CO2-to-HCOOH electrolysis represents a sustainable route for value-added CO2 transformations. However, competing hydrogen evolution reaction (HER) in acid remains a great challenge for selective CO2-to-HCOOH production, especially in industrial-level current densities. Main group metal sulfides derived S-doped metals have demonstrated enhanced CO2-to-HCOOH selectivity in alkaline and neutral media by suppressing HER and tuning CO2 reduction intermediates. Yet stabilizing these derived sulfur dopants on metal surfaces at large reductive potentials for industrial-level HCOOH production is still challenging in acidic medium. Herein, we report a phase-engineered tin sulfide pre-catalyst (π-SnS) with uniform rhombic dodecahedron structure that can derive metallic Sn catalyst with stabilized sulfur dopants for selective acidic CO2-to-HCOOH electrolysis at industrial-level current densities. In situ characterizations and theoretical calculations reveal the π-SnS has stronger intrinsic Sn-S binding strength than the conventional phase, facilitating the stabilization of residual sulfur species in the Sn subsurface. These dopants effectively modulate the CO2RR intermediates coverage in acidic medium by enhancing *OCHO intermediate adsorption and weakening *H binding. As a result, the derived catalyst (Sn(S)-H) demonstrates significantly high Faradaic efficiency (92.15 %) and carbon efficiency (36.43 %) to HCOOH at industrial current densities (up to −1 A cm−2) in acidic medium. Stabilizing sulfur dopants on metal surfaces is important but challenging in acidic CO2 to HCOOH electrolysis, especially under high current densities. Here the authors present phase engineered SnS pre-catalyst with stronger intrinsic Sn-S binding strength for CO2 conversion to HCOOH at > 1 A cm−2 in acidic medium. [ABSTRACT FROM AUTHOR]

The FeO/Fe bond in the oxide scale is very tight, and FeO fracture is complicated under external force. In this study, the deformation behavior and mechanical properties of single-crystal FeO/Fe under nanoindentation are analyzed by the molecular dynamics (MD) simulation method. The results show that: 1. loading stage: the load increases with the increase in the loading rate; unloading stage: the load drop rate increases with the increase in the unloading rate in the early stage, and the opposite in the middle and late stage. 2. The dislocation density and the phase transition of the HCP structure decrease with the increase in the indentation rate, and the total volume of defect atoms increases with the increase in the indentation rate. 3. When the indenter is in the FeO layer, the hardness and elastic modulus increase with the increase in the indentation rate. 4. The hydrostatic stress and Von Mises stress analysis show that the average stress value increases with the increase in the indentation rate, and coexistence of compressive and tensile stress inside the model. This study provides essential help for further exploration of the deformation behavior and mechanical properties of oxide scales. [ABSTRACT FROM AUTHOR]

Purpose: To report a previously undocumented variant of sternalis. Methods: An unusual muscle was observed during routine dissection. Results: The sternalis muscle located in the right thoracic region originated from the superior portion of the rectus abdominis sheath and 5–6th costal cartilages, crossed the midline and attached at the sternum. The muscle fibers then ascended with the left sternocleidomastoid muscle as an additional fasciculus, of which the superior ends were finally terminated at the left mastoid process. The sternalis muscle of the thoracic region was innervated by the anterior cutaneous branches of right intercostal nerve, while the additional fasciculus ascended with the left sternocleidomastoid muscle was innervated by the branches of left accessory nerve. Conclusions: This study presents a unilateral sternalis muscle with the contralateral sternocleidomastoid variation. It will enhance the exhaustive classification of sternalis, and provide significant information to radiologists, angiologists and surgeons for better interpretation of images and safer interventions. [ABSTRACT FROM AUTHOR]

The effects of plant-based carbon source addition on wastewater NO3−-N removal and the involved microorganisms, especially denitrifying bacteria, were investigated. A synthetic wastewater (NO3−-N, 15 mg/L) was treated through the batch experiment, which included three inoculation cycles (7 days/cycle), and was conducted at 25 °C. Four natural plant substrates, namely, rice straw (RS), wheat straw (WS), ryegrass (RG), and reed (RD), were used as carbon sources and supplemented at the rate of 1% (w/v). The results showed that both RS and WS performed well in promoting NO3−-N removal (79.55–97.07%). While RG removed only 22.08% of NO3−-N in the first cycle, the removal efficiency increased afterward (86.09–95.82%). Conversely, the NO3−-N removal rate of RD decreased from 95.10 to 24.77% as a result of its low ability to supply carbon. With respect to the microorganisms, the RS treatment resulted in more bacteria and denitrifying genes such as narG, nirK, nirS, and norB than other treatments, while the highest number of nosZ gene copies was recorded in the WS treatment. Sequencing results revealed that Firmicutes (18.19–56.96%), Proteobacteria (38.82–74.80%), and Bacteroidetes (3.15–4.15%) were three dominant bacterial phyla for RS, WS, and RD treatments. Furthermore, the genera Enterobacter, Massilia, and Bacillus were the main denitrifying bacteria participating in the NO3−-N removal. Furthermore, correlation analysis indicated that the denitrifying genus Sphingobacterium played an important role in enhancing nitrogen removal. This study suggested that RS is the superior plant-based carbon source for denitrifying bioreactors used in agricultural runoff treatment. [ABSTRACT FROM AUTHOR]

B Correction: Applied Physics A (2023) 129:151 b https://doi.org/10.1007/s00339-022-06379-y In this article the affiliation details for affiliations 1 and 3 incorrectly given. School of Mechanical, Materials, Mechatronic and Biomedical Engineering, University of Wollongong, Wollongong, NSW 2522, Australia The original article has been corrected. [Extracted from the article]

MicroRNAs (miRNAs) have been reported to be involved in each stage of tumor development in various types of cancers. We have previously showed that miR-16 is downregulated in cancer and acts as a tumor suppressor. Other studies indicated that hepatocyte growth factor (HGF)/c-Met is implicated in proliferation, migration, and other pathophysiological processes. However, little is known about the relationship between miR-16 and HGF/c-Met in gastric cancer (GC). In the present study, we used bioinformatics tools and related experiments to search for miRNAs targeting HGF. Here, we found that miR-16 suppressed HGF protein expression by directly targeting 3′-untranslated region (UTR) of HGF mRNA. Subsequently, it was illustrated the downregulation of miR-16 promotes, while overexpressed of miR-16 significantly inhibits cell proliferation and migration by negatively regulating HGF/c-Met pathway. Moreover, the biological role of HGF in GC cells was determined by using HGF siRNA and HGF-overexpressing plasmid, respectively. To conclude, our results provide a potential target by using miR-16 for the future clinical treatment of GC. [ABSTRACT FROM AUTHOR]

In this study, we found that pretreatment with low dose of lipopolysaccharide (LPS), also known as lipoglycans and endotoxin, obviously attenuated liver injury caused by diethylnitrosamine (DEN) in mice. This protective effect was described by decreased ALT, TNF-α, and IL-1β and increased TGF-β production. However, Toll-like receptor 4-deficient (TLR4) or macrophages depletion abolished this protection in mice, which revealed Kupffer cells (KCs) and TLR4 to be crucial for the prevention of LPS against DEN-induced damage. Further study revealed that LPS pretreatment induced the KCs to M2 polarization and impaired the signaling of MAPKs and NF-κB that mediated the production of inflammatory cytokines. Moreover, T regulatory cells (Tregs) were also recruited to the liver, which may mediate immunosuppression and participate in the prevention of DEN-induced injury. Our results suggested that LPS protected against DEN-induced hepatitis via induction of M2 Kupffer cells and recruitment of Tregs, which contributes to liver tolerance in TLR4-dependent mechanism. [ABSTRACT FROM AUTHOR]

Multidrug resistance (MDR) is the main obstacle in breast cancer chemotherapy, a reversal reagent with high reversal effect but low toxicity is the hotpot issue at present. The antidepressant fluoxetine (FLX) is a new highly effective chemosensitizer; however, the possible mechanism of FLX in reversal of MDR is unclear. In this study, the effect of FLX on MDR mediated by apoptosis was researched in resistant/sensitive breast cancer cells, which treated by FLX/adriamycin (ADM)/paclitaxel (PTX) alone or FLX-ADM, FLX-PTX combination. Apoptosis assay demonstrated that FLX combined with ADM enhanced the proportion of apoptosis remarkably in MCF-7/ADM but not MCF-7 cells; however, increased the apoptosis rates in both cells when FLX-PTX combination. Results of apoptosis proteins assay showed a upgrade of p53 and a downgrade of Bcl-2 level by FLX-ADM or FLX-PTX combinations in both cells. Our findings indicated that by synergism with anticancer drugs, FLX modulation of apoptosis via targeting p53 and Bcl-2 expression, FLX reverse the breast cancer cell's resistance and enhance the chemosensitivity to ADM and PTX. [ABSTRACT FROM AUTHOR]

Objective: Decline, disruption, or alterations of nicotinic cholinergic mechanisms contribute to cognitive dysfunctions like Alzheimer's disease (AD). Although amyloid-β (Aβ) aggregation is a pathological hallmark of AD, the mechanisms by which Aβ peptides modulate cholinergic synaptic transmission and memory loss remain obscure. This study was aimed to investigate the potential synaptic modulation by Aβ of the cholinergic synapses between olfactory receptor neurons and projection neurons (PNs) in the olfactory lobe of the fruit fly. Methods: Cholinergic spontaneous and miniature excitatory postsynaptic current (mEPSC) were recorded with whole-cell patch clamp from PNs in Drosophila AD models expressing Aβ40, Aβ42, or Aβ42Arc peptides in neural tissue. Results: In fly pupae (2 days before eclosion), overexpression of Aβ42 or Aβ42Arc, but not Aβ40, led to a significant decrease of mEPSC frequency, while overexpression of Aβ40, Aβ42, or Aβ42Arc had no significant effect on mEPSC amplitude. In contrast, Pavlovian olfactory associative learning and lifespan assays showed that both short-term memory and lifespan were decreased in the Drosophila models expressing Aβ40, Aβ42, or Aβ42Arc. Conclusion: Both electrophysiological and behavioral results showed an effect of Aβ peptide on cholinergic synaptic transmission and suggest a possible mechanism by which Aβ peptides cause cholinergic neuron degeneration and the consequent memory loss. [ABSTRACT FROM AUTHOR]

An isolate of a Pseudomonas sp. uses the l-NCC ( N-carbamoyl- l-cysteine) pathway to convert dl-2-amino-Δ-thiazoline-4-carboxylic acid ( dl-ATC) to l-cysteine. Genes encoding ATC racemase (AtcA), l-ATC hydrolase (AtcB) and l-NCC amidohydrolase (AtcC), involved in this pathway, were cloned from the Pseudomonas sp. and expressed in Escherichia coli BL21 via pET-28a(+). The resulting enzymes were purified, their functions identified, and their biochemical properties are described. In vitro catalysis experiments, using these enzymes, revealed that the bioconversion rate of l-cysteine from dl-ATC in the presence of AtcA was more efficient than in the absence of AtcA. This is the first report describing simultaneous cloning and expression of atcA, atcB and atcC and characterization of their enzymes for l-cysteine production from dl-ATC via the l-NCC pathway, enabling the complete l-NCC pathway to be elucidated. [ABSTRACT FROM AUTHOR]

Members of the transient receptor potential (TRP) ion channels conduct cations into cells. They mediate functions ranging from neuronally mediated hot and cold sensation to intracellular organellar and primary ciliary signaling. Here we report a cryo-electron microscopy (cryo-EM) structure of TRPC4 in its unliganded (apo) state to an overall resolution of 3.3 Å. The structure reveals a unique architecture with a long pore loop stabilized by a disulfide bond. Beyond the shared tetrameric six-transmembrane fold, the TRPC4 structure deviates from other TRP channels with a unique cytosolic domain. This unique cytosolic N-terminal domain forms extensive aromatic contacts with the TRP and the C-terminal domains. The comparison of our structure with other known TRP structures provides molecular insights into TRPC4 ion selectivity and extends our knowledge of the diversity and evolution of the TRP channels. Members of the transient receptor potential (TRP) ion channels conduct cations into cells upon activation by a variety of signals. Here authors present the cryo-EM structure of TRPC4 in its unliganded (apo) state, which provides molecular insights into TRPC4's ion selectivity and TPR channel evolution. [ABSTRACT FROM AUTHOR]

Two-dimensional metal-organic frameworks represent a family of materials with attractive chemical and structural properties, which are usually prepared in the form of bulk powders. Here we show a generic approach to fabricate ultrathin nanosheet array of metal-organic frameworks on different substrates through a dissolution-crystallization mechanism. These materials exhibit intriguing properties for electrocatalysis including highly exposed active molecular metal sites owning to ultra-small thickness of nanosheets, improved electrical conductivity and a combination of hierarchical porosity. We fabricate a nickel-iron-based metal-organic framework array, which demonstrates superior electrocatalytic performance towards oxygen evolution reaction with a small overpotential of 240 mV at 10 mA cm−2, and robust operation for 20,000 s with no detectable activity decay. Remarkably, the turnover frequency of the electrode is 3.8 s−1 at an overpotential of 400 mV. We further demonstrate the promise of these electrodes for other important catalytic reactions including hydrogen evolution reaction and overall water splitting. [ABSTRACT FROM AUTHOR]