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Integrated fixed-film activated sludge (IFAS) system, an improvement of the activated sludge process, combines the advantages of both attached sludge (AS) and suspended sludge (SS). This study aimed to fully decipher the roles of AS and SS in simultaneous N and P removal in an IFAS system through metagenomic analysis. It was found that AS contributed about 84.04%, 97%, and 95.12% to exogenous NO3--N reduction, endogenous NO3--N reduction, and endogenous NO2--N reduction, respectively. Compared with AS, SS exhibited a greater contribution to anaerobic P release (69.06%) and aerobic P uptake (73.48%). Nitrate and nitrite reductase enzymes showed higher activities in AS, while the activities of exopolyphosphatase and alkaline phosphatase D were more active in SS. P content further indicated that in AS, only a small amount of P was stored in EPS, with most presented intracellularly. In SS, the amount of P stored in EPS was found to be higher. Metagenomic analysis revealed genes related to the synthesis and degradation of endogenous carbon were higher in AS, whereas the TCA cycle exhibited higher activity in SS. P removal-related genes (such as ppk2, ppx, and adk) was significantly higher in SS than in AS. The alteration of genes associated with nitrogen metabolism suggested that the microbes in AS had a higher capacity for nitrification and denitrification. In summary, the discrepancy in the roles of AS and SS in N and P removal in IFAS can be attributed to variations in enzyme activity, P storage in EPS, microbial community composition, and functional gene abundance.
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One of the most prevalent heavy metals found in rural sewage is Zn(II), while its effect on simultaneous nitrification, denitrification and phosphorus removal (SNDPR) remains unclear. In this work, the responses of SNDPR performance to long-term Zn(II) stress were investigated in a cross-flow honeycomb bionic carrier biofilm system. The results indicated that Zn(II) stress at 1 and 5 mg L-1 could increase nitrogen removal. Maximum ammonia nitrogen, total nitrogen, and phosphorus removal efficiencies of up to 88.54%, 83.19%, and 83.65% were obtained at Zn(II) concentration of 5 mg L-1. The functional genes, such as archaeal amoA, bacterial amoA, NarG, NirS, NapA, and NirK, also reached the highest value at 5 mg L-1 Zn(II), with the absolute abundances of 7.73 × 105, 1.57 × 106, 6.68 × 108, 1.05 × 109, 1.79 × 108, and 2.09 × 108 copies·g-1 dry weight, respectively. The neutral community model demonstrated that deterministic selection was responsible for the system's microbial community assembly. Additionally, response regimes with extracellular polymeric substances and cooperation among microorganisms facilitated the stability of the reactor effluent. Overall, the findings of this paper contribute to improving the efficiency of wastewater treatment.
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Microbiota , Nitrificação , Desnitrificação , Fósforo , Reatores Biológicos/microbiologia , Esgotos/microbiologia , Nitrogênio , Desempenho Físico Funcional , Zinco , Eliminação de Resíduos Líquidos/métodosRESUMO
Irradiation damage is a key issue for the reliability of semiconductor devices under extreme environments. For decades, the ionizing-irradiation-induced damage in transistors with silica-silicon (SiO2 -Si) structures at room temperature has been modeled by a uniform generation of E'γ centers in the bulk silica region through the capture of irradiation-induced holes, and an irreversible conversion from E'γ to Pb centers at the SiO2 /Si interface through reactions with hydrogen molecules (H2 ). However, the traditional model fails to explain experimentally-observed dose dependence of the defect concentrations, especially at low dose rate. Here, it is proposed that the generation of E'γ centers is decelerated because the holes migrate dispersively in disordered silica and the diffusion coefficient decays as the irradiation goes on. It is also proposed that the conversion between E'γ and Pb centers is reversible because the huge activation energy of the reverse reaction can be reduced by a "phonon-kick" effect of the vibrational energy of H2 and Pb centers transferred from nearby nonradiative recombination centers. Experimental studies are carried out to demonstrate that the derived analytic model based on these two new concepts can consistently explain the fundamental but puzzling dose dependence of the defect concentrations for an extremely wide dose rate range.
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Dióxido de Silício , Silício , Reprodutibilidade dos Testes , Silício/química , Dióxido de Silício/químicaRESUMO
We have studied the mechanisms by which meiotic arrest maintenance (MAM) with roscovitine, female sexual maturity, and the surrounded nucleoli (SN) chromatin configuration improve the competence of mouse oocytes by observing the expression of oocyte competence-related genes in non-surrounded nucleoli (NSN) and SN oocytes from prepubertal and adult mice following maturation with or without MAM. The results demonstrated that MAM with roscovitine significantly improved the developmental potential of adult SN and prepubertal NSN oocytes, but had no effect on that of prepubertal SN oocytes. Without MAM, while 40% of the 2-cell embryos derived from prepubertal SN oocytes developed into 4-cell embryos, none of the 2-cell embryos derived from prepubertal NSN oocytes did, and while 42% of the 4-cell embryos derived from adult SN oocytes developed into blastocysts, only 1% of the 4-cell embryos derived from prepubertal SN oocytes developed into blastocysts. Furthermore, MAM with roscovitine, SN configuration, and female sexual maturity significantly increased the mRNA levels of competence-beneficial genes and decreased those of competence-detrimental genes. In conclusion, our results suggest that MAM with roscovitine, SN chromatin configuration, and female sexual maturity improve oocyte competence by regulating the expression of competence-related genes, suggesting that Oct4, Stella, Mater, Zar1, Mapk8, and Bcl2 are oocyte competence-beneficial genes, whereas Foxj2, Ship1, and Bax are competence-detrimental genes.
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Nucléolo Celular/metabolismo , Meiose/efeitos dos fármacos , Oócitos/citologia , Roscovitina/farmacologia , Animais , Blastocisto , Cromatina/metabolismo , Técnicas de Cocultura , Células do Cúmulo/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Técnicas de Maturação in Vitro de Oócitos/métodos , Camundongos , Folículo Ovariano/metabolismo , Transcrição GênicaRESUMO
Encryption is an important step for secure data transmission, and a true random number generator (TRNG) is a key building block in many encryption algorithms. Static random-access memory (SRAM) chips can be easily available sources of true random numbers, benefiting from noisy SRAM cells whose start-up values flip between different power-on cycles. Embarking from this phenomenon, a novel performance (i.e., randomness and throughput) improvement method of SRAM-based TRNG is proposed, and its implementation can be divided into two phases: irradiation exposure and hardware postprocessing. As the randomness of original SRAM power-on values is fairly low, ionization irradiation is utilized to enhance its randomness, and the min-entropy can increase from about 0.03 to above 0.7 in the total ionizing irradiation (TID) experiments. Additionally, while the data remanence effect hampers obtaining random bitstreams with high speed, the ionization irradiation can also weaken this impact and improve the throughput of TRNG. In the hardware postprocessing stage, Secure Hash Algorithm 256 (SHA-256) is implemented on a Field Programmable Gate Array (FPGA) with clock frequency of 200 MHz. It can generate National Institute of Standards and Technology (NIST) SP 800-22 compatible true random bitstreams with throughput of 178 Mbps utilizing SRAM chip with 1 Mbit memory capacity. Furthermore, according to different application scenarios, the throughput can be widely scalable by adjusting clock frequency and SRAM memory capacity, which makes the novel TRNG design applicable for various Internet of Things (IOT) devices.
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MicroRNAs (miRNAs), a group of small noncoding RNAs, are widely involved in the regulation of gene expression via binding to complementary sequences at 3'-untranslated regions (3'-UTRs) of target messenger RNAs. Recently, downregulation of miR-133b has been detected in various human malignancies. Here, the potential biological role of miR-133b in bladder cancer (BC) was investigated. In this study, we found the expression of miR-133b was markedly downregulated in BC tissues and cell lines (5637 and T24), and was correlated with poor overall survival. Notably, transgelin 2 (TAGLN2) was found to be widely upregulated in BC, and overexpression of TAGLN2 also significantly increased risks of advanced TMN stage. We further identified that upregulation of miR-133b inhibited glucose uptake, invasion, angiogenesis, colony formation and enhances gemcitabine chemosensitivity in BC cell lines by targeting TAGLN2. Additionally, we showed that miR-133b promoted the proliferation of BC cells, at least partially through a TAGLN2-mediated cell cycle pathway. Our results suggest a novel miR-133b/TAGLN2/cell cycle pathway axis controlling BC progression; a molecular mechanism which may offer a potential therapeutic target.
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Pontos de Checagem do Ciclo Celular/genética , MicroRNAs/genética , Proteínas dos Microfilamentos/metabolismo , Proteínas Musculares/metabolismo , Neovascularização Patológica/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/prevenção & controle , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Humanos , Camundongos , Camundongos Nus , MicroRNAs/biossíntese , Invasividade Neoplásica/genética , Transplante de Neoplasias , Transplante HeterólogoRESUMO
Mechanisms by which psychological stress damages oocytes are largely undetermined. Although a previous study showed that the stress-induced corticotrophin-releasing hormone (CRH) elevation impaired oocyte competence by triggering apoptosis of ovarian cells, how CRH causes apoptosis in ovarian cells and oocytes is unknown. In this study, we have examined the hypothesis that restraint stress (RS)-induced CRH elevation triggers apoptosis of ovarian cells and impairs oocyte competence through activating the Fas/FasL system. The results showed that RS of female mice impaired oocyte competence, enhanced expression of CRH and CRH receptor (CRH-R) in the ovary, and induced apoptosis while activating the Fas/FasL system in mural granulosa cells (MGCs) and oocytes. Injecting mice with CRH-R1 antagonist antalarmin significantly alleviated the adverse effect of RS on oocyte developmental potential. Treatment of cultured MGCs recapitulated the effects of CRH and antalarmin on apoptosis and Fas/FasL expression in MGCs. Silencing FasL gene by RNA interference in cultured MGCs further confirmed the involvement of the Fas/FasL system in the CRH triggered apoptosis of ovarian cells. It is concluded that the RS-induced CRH elevation triggers apoptosis of ovarian cells and impairs oocyte competence via activation of the Fas/FasL system.
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Hormônio Liberador da Corticotropina/metabolismo , Proteína Ligante Fas/metabolismo , Oócitos/metabolismo , Ovário/citologia , Ovário/metabolismo , Restrição Física/fisiologia , Receptor fas/metabolismo , Animais , Apoptose/fisiologia , Células Cultivadas , Feminino , Células da Granulosa/citologia , Células da Granulosa/metabolismo , Camundongos , Oócitos/citologia , Oócitos/crescimento & desenvolvimento , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Restrição Física/efeitos adversos , Restrição Física/psicologia , Estresse PsicológicoRESUMO
BACKGROUND/AIMS: Acute rejection (AR) is a major complication post renal transplantation, with no widely-accepted non-invasive biomarker. This study aimed to explore the expression profiles of long non-coding RNAs (lncRNAs) in the peripheral blood (PB) of renal transplant recipients and their potential diagnostic values. METHODS: The genome-wide lncRNA expression profiles were analyzed in 150 PB samples from pediatric and adult renal transplant (PRTx and ARTx) cohorts. The diagnostic performance of differentially expressed lncRNA was determined using receiver operator characteristic curve, with area under the curve (AUC) and 95% confidential interval (CI). Finally, a risk score was constructed with logistical regression model. RESULTS: A total of 162 lncRNAs were found differentially expressed in PRTx cohort, while 163 in ARTx cohort. Among these identified lncRNAs, 23 deregulated accordingly in both cohorts, and could distinguish AR recipients from those without AR. Finally, a risk score with two most significant lncRNAs (AF264622 and AB209021) was generated and exhibited excellent diagnostic performance in both PRTx (AUC:0.829, 95% CI:0.735-0.922) and ARTx cohorts (AUC: 0.889, 95% CI: 0.817-0.960). CONCLUSION: A molecular signature of two lncRNAs in PB could serve as a novel non-invasive biomarker for the diagnosis of AR in both pediatric and adult renal transplant recipients.
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Rejeição de Enxerto/patologia , Transplante de Rim , RNA Longo não Codificante/sangue , Doença Aguda , Área Sob a Curva , Biomarcadores/sangue , Estudos de Coortes , Rejeição de Enxerto/genética , Rejeição de Enxerto/metabolismo , Humanos , Curva ROC , Transcriptoma , Transplante HomólogoRESUMO
Buchnera aphidicolais an obligate endosymbiont that provides aphids with several essential nutrients. Though much is known about aphid-Buchnera interactions, the effect of the host plant on Buchnera population size remains unclear. Here we used quantitative PCR (qPCR) techniques to explore the effects of the host plant on Buchnera densities in the cotton-melon aphid, Aphis gossypii Buchneratiters were significantly higher in populations that had been reared on cucumber for over 10 years than in populations maintained on cotton for a similar length of time. Aphids collected in the wild from hibiscus and zucchini harbored more Buchnera symbionts than those collected from cucumber and cotton. The effect of aphid genotype on the population size of Buchnera depended on the host plant upon which they fed. When aphids from populations maintained on cucumber or cotton were transferred to novel host plants, host survival and Buchnera population size fluctuated markedly for the first two generations before becoming relatively stable in the third and later generations. Host plant extracts from cucumber, pumpkin, zucchini, and cowpea added to artificial diets led to a significant increase in Buchnera titers in the aphids from the population reared on cotton, while plant extracts from cotton and zucchini led to a decrease in Buchnera titers in the aphids reared on cucumber. Gossypol, a secondary metabolite from cotton, suppressed Buchnera populations in populations from both cotton and cucumber, while cucurbitacin from cucurbit plants led to higher densities. Together, the results suggest that host plants influence Buchnera population processes and that this may provide phenotypic plasticity in host plant use for clonal aphids.
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Afídeos/microbiologia , Carga Bacteriana , Buchnera/crescimento & desenvolvimento , Plantas/parasitologia , Densidade Demográfica , Animais , Reação em Cadeia da Polimerase em Tempo RealRESUMO
PURPOSE: To report the outcomes of toric intraocular lens implantation in patients with glaucoma and corneal astigmatism. METHODS: One hundred twenty-six eyes of 87 patients with glaucoma and corneal astigmatism that underwent cataract surgery with an AcrySof toric intraocular lens (Alcon Laboratories, Inc., Fort Worth, TX) implant were selected for this single-center, retrospective case series. Corrected distance visual acuity, intraocular pressure, and refractive astigmatism were measured in each eye preoperatively and postoperatively. Uncorrected distance visual acuity and toric alignment were measured postoperatively. RESULTS: The uncorrected distance visual acuity was 0.04 ± 0.08 logMAR (20/22 Snellen) for all eyes. Ninety-eight percent of all eyes achieved an uncorrected distance visual acuity of 20/40 or better, with 76% achieving 20/25 or better and 47% achieving 20/20. The corrected distance visual acuity for all eyes was 0.01 ± 0.03 logMAR (20/20.5 Snellen) postoperatively. The refractive cylinder improved from 1.47 ± 1.10 diopters preoperatively to 0.31 ± 0.37 diopters postoperatively. The residual refractive cylinder was 1.00 diopter or less in 97% of eyes, 0.75 diopters or less in 90% of eyes, and 0.50 diopters or less in 83% of eyes. Mean misalignment was 4.4° ± 5.1°. Intraocular pressure decreased by a mean of 2.3 ± 3.3 mm Hg following the surgery. CONCLUSION: Toric intraocular lenses can reliably reduce astigmatism and improve uncorrected vision in eyes with cataract and glaucoma.
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Astigmatismo/cirurgia , Catarata/terapia , Glaucoma/complicações , Implante de Lente Intraocular , Lentes Intraoculares , Facoemulsificação , Idoso , Astigmatismo/complicações , Astigmatismo/fisiopatologia , Catarata/complicações , Catarata/fisiopatologia , Córnea/fisiopatologia , Feminino , Glaucoma/fisiopatologia , Humanos , Pressão Intraocular/fisiologia , Masculino , Pseudofacia/fisiopatologia , Refração Ocular/fisiologia , Estudos Retrospectivos , Tonometria Ocular , Resultado do Tratamento , Acuidade Visual/fisiologia , Campos Visuais/fisiologiaRESUMO
The catalytic performance of immobilized lipase is greatly influenced by functional support, which attracts growing interest for designing supports to achieve their promotive catalytic activity. Many lipases bind strongly to hydrophobic surfaces where they undergo interfacial activation. Herein, the behavioral differences of lipases with distinct lid structures on interfaces of varying hydrophobicity levels were firstly investigated by molecular simulations. It was found that a reasonable hydrophilic/hydrophobic surface could facilitate the lipase to undergo interfacial activation. Building on these findings, a novel "nest"-like superhydrophobic ZIFs (ZIFN) composed of hydrophobic ligands was prepared for the first time and used to immobilize lipase from Aspergillus oryzae (AOL@ZIFN). The AOL@ZIFN exhibited 2.0-folds higher activity than free lipase in the hydrolysis of p-Nitrophenyl palmitate (p-NPP). Especially, the modification of superhydrophobic ZIFN with an appropriate amount of hydrophilic tannic acid can significantly improve the activity of the immobilized lipase (AOL@ZIFN-TA). The AOL@ZIFN-TA exhibited 30-folds higher activity than free lipase, and still maintained 82% of its initial activity after 5 consecutive cycles, indicating good reusability. These results demonstrated that nanomaterials with rational arrangement of the hydrophilic/hydrophobic surface could facilitate the lipase to undergo interfacial activation and improve its activity, displaying the potential of the extensive application.
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Enzimas Imobilizadas , Interações Hidrofóbicas e Hidrofílicas , Lipase , Propriedades de Superfície , Lipase/química , Lipase/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Aspergillus oryzae/enzimologia , Simulação de Dinâmica Molecular , Hidrólise , Nanoestruturas/química , Tamanho da PartículaRESUMO
Self-healing hydrogels have attracted wide attention because of their potential applications in various fields. However, the complex processes, environmental requirements, and insufficient functionality limit their practical application. Herein, we synthesized a chitosan quaternary ammonium salt-oxidized sodium alginate-glycerol-calcium ion (HACC-OSA-Gly-Ca2+) biobased hydrogel with a multi-network structure that exhibits excellent self-healing abilities. This was achieved by utilizing reversible dynamic imine bonding, electrostatic interactions, Ca2+ ions as crosslinking points, and hydrogen bonding. The oxidation of sodium alginate (SA) with sodium periodate was carried out to obtain oxidized sodium alginate (OSA) with varying oxidation degrees. The resulting OSAs were then introduced into a glycerol-water solvent system containing chitosan quaternary ammonium salt (HACC) and calcium chloride, and this reaction successfully prepared the biobased eco-friendly self-healing hydrogel. The impacts of the oxidation degree (OD) of OSA on the microscopic morphology, mechanical properties, viscoelastic properties, swelling properties, and self-healing properties of the corresponding synthetic hydrogels were investigated. The outcomes indicated that the optimal HACC-OSA-Gly-Ca2+ hydrogel possessed good mechanical properties, with a tensile stress of 0.0132 MPa and elongation at break of 551.38%. Furthermore, the multiple bond interactions led to a high self-healing ratio (100%), with an elongation at break of about 614.29%, and excellent adhesion ability (average peel strength of 6.38 kN m-1) on various substrates. Additionally, the composite hydrogels exhibited excellent water retention, thermal stability, and resilience, making them promising for various potential applications. Moreover, the properties of the composite hydrogels could be facilely and finely tuned by varying the oxidation degree of OSA and ratio of each component. Thus, the presented strategy could enrich the construction as well as application of biopolymer-based self-healing hydrogels.
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Protected areas (PAs) play a crucial role in halting biodiversity loss and mitigating climate change. However, research on the advantages of integrating biodiversity conservation and climate mitigation within PAs remains limited, and there is a deficiency in holistic, scientifically supported management strategies. To address these gaps, we conducted a case study in China, comparing the conservation effectiveness of designating conservation priorities considering either single or multiple objectives, including biodiversity conservation and carbon neutrality. The results showed that integrating multiple values could truly increase the effectiveness of PAs compared to a single value considered. Over 1/4 of China's terrestrial area had a significant contribution for both biodiversity conservation and carbon neutrality, yet remained unprotected. Expanding PAs in these areas holds tremendous win-win biodiversity conservation and carbon neutrality opportunity. We delineated different conservation priorities for comprehensive management and outlined strategies for different types of areas. The framework presented in this study can serve as a reference for other places with comparable scales or management objectives.
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Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Carbono , Biodiversidade , ChinaRESUMO
Microplastics (MPs) pollution has emerged as a global concern, and wastewater treatment plants (WWTPs) are one of the potential sources of MPs in the environment. However, the effect of polyethylene MPs (PE) on nitrogen (N) removal in moving bed biofilm reactor (MBBR) remains unclear. We hypothesized that PE would affect N removal in MBBR by influencing its microbial community. In this study, we investigated the impacts of different PE concentrations (100, 500, and 1000 µg/L) on N removal, enzyme activities, and microbial community in MBBR. Folin-phenol and anthrone colorimetric methods, oxidative stress and enzyme activity tests, and high-throughput sequencing combined with bioinformation analysis were used to decipher the potential mechanisms. The results demonstrated that 1000 µg/L PE had the greatest effect on NH4+-N and TN removal, with a decrease of 33.5 % and 35.2 %, and nitrifying and denitrifying enzyme activities were restrained by 29.5-39.6 % and 24.6-47.4 %. Polysaccharide and protein contents were enhanced by PE, except for 1000 µg/L PE, which decreased protein content by 65.4 mg/g VSS. The positive links of species interactions under 1000 µg/L PE exposure was 52.07 %, higher than under 500 µg/L (51.05 %) and 100 µg/L PE (50.35 %). Relative abundance of some metabolism pathways like carbohydrate metabolism and energy metabolism were restrained by 0.07-0.11 % and 0.27-0.4 %. Moreover, the total abundance of nitrification and denitrification genes both decreased under PE exposure. Overall, PE reduced N removal by affecting microbial community structure and species interactions, inhibiting some key metabolic pathways, and suppressing key enzyme activity and functional gene abundance. This paper provides new insights into assessing the risk of MPs to WWTPs, contributing to ensuring the health of aquatic ecosystems.
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Biofilmes , Reatores Biológicos , Microbiota , Nitrogênio , Polietileno , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Nitrogênio/metabolismo , Reatores Biológicos/microbiologia , Poluentes Químicos da Água/análise , Eliminação de Resíduos Líquidos/métodos , Microbiota/efeitos dos fármacos , Microplásticos , Águas Residuárias/químicaRESUMO
Environment-friendly and biodegradable packaging materials have attracted widespread attention. Development of green solutions to extend the fruit shelf life and address fruit preservation thus has a far-reaching impact. In this study, high-barrier white cardboard (WC) was prepared by a facile coating method. Compared with the WC substrate, the WVP value of the polyvinylidene chloride (PVDC) emulsion-coated WC (3.46 × 10-11 g m m-2 s-1 kPa-1) decreased 73.8% and the OP value (14.8 cm3 m-2 day-1·Pa-1) decreased 61.9%. In addition, the mechanical properties of the PVDC emulsion-coated WC increased significantly. The weight loss rate and decay rate of the stored fruits packaged with PVDC emulsion-coated WC decreased by about 5%. The high barrier PVDC emulsion-coated WC with excellent mechanical properties, good barrier effect, and preservation function was successfully prepared. Benefitting from these investigated characteristics, the obtained coated WC can be used to package fruits to reduce water loss and delay ripening, and thus extend their shelf life, exhibiting a favorable effect on blueberry and grape storage. Overall, the fabricated eco-friendly coated white cardboard has shown great potential for biodegradable packaging applications. We believe the current work presents an approach to address perishable fruit preservation and provide a supplement alternative.
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Ciprofloxacin (CIP) has received considerable attention in recent decades due to its high ecological risk. However, little is known about the potential response of macrophytes and microbes to varying levels of CIP exposure in constructed wetlands. Therefore, lab-scale manganese ore-based tidal flow constructed wetlands (MO-TFCWs) were operated to evaluate the responses of macrophytes and microbes to CIP over the long term. The results indicated that total nitrogen removal improved from 79.93% to 87.06% as CIP rose from 0 to 4 mg L-1. The chlorophyll content and antioxidant enzyme activities in macrophytes were enhanced under CIP exposure, but plant growth was not inhibited. Importantly, CIP exposure caused a marked evolution of the substrate microbial community, with increased microbial diversity, expanded niche breadth and enhanced cooperation among the top 50 genera, compared to the control (no CIP). Co-occurrence network also indicated that microorganisms may be more inclined to co-operate than compete. The abundance of the keystone bacterium (involved in nitrogen transformation) norank_f__A0839 increased from 0.746% to 3.405%. The null model revealed drift processes (83.33%) dominated the community assembly with no CIP and 4 mg L-1 CIP. Functional predictions indicated that microbial carbon metabolism, electron transfer and ATP metabolism activities were enhanced under prolonged CIP exposure, which may contribute to nitrogen removal. This study provides valuable insights that will help achieve stable nitrogen removal from wastewater containing antibiotic in MO-TFCWs.
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Ciprofloxacina , Manganês , Nitrogênio , Poluentes Químicos da Água , Áreas Alagadas , Ciprofloxacina/farmacologia , Ciprofloxacina/metabolismo , Manganês/metabolismo , Nitrogênio/metabolismo , Poluentes Químicos da Água/metabolismo , Antibacterianos , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Plantas/metabolismo , Biodegradação Ambiental , Eliminação de Resíduos Líquidos/métodosRESUMO
A limited understanding of microbial interactions and community assembly mechanisms in constructed wetlands (CWs), particularly with different substrates, has hampered the establishment of ecological connections between micro-level interactions and macro-level wetland performance. In this study, CWs with distinct substrates (zeolite, CW_A; manganese ore, CW_B) were constructed to investigate the nutrient removal efficiency, microbial interactions, metabolic mechanisms, and ecological assembly for treating rural sewage with a low carbon-to-nitrogen ratio. CW_B showed higher removal of ammonia nitrogen and total nitrogen by about 1.75-6.75 % and 3.42-5.18 %, respectively, compared to CW_A. Candidatus_Competibacter (denitrifying glycogen-accumulating bacteria) was the dominant microbial genus in CW_A, whereas unclassified_f_Blastocatellaceae (involved in carbon and nitrogen transformation) dominated in CW_B. The null model revealed that stochastic processes (drift) dominated community assembly in both CWs; however, deterministic selection accounted for a higher proportion in CW_B. Compared to those in CW_A, the interactions between microbes in CW_B were more complex, with more key microbes involved in carbon, nitrogen, and phosphorus conversion; the synergistic cooperation of functional bacteria facilitated simultaneous nitrification-denitrification. Manganese ores favour biofilm formation, increase the activity of the electron transport system, and enhance ammonia oxidation and nitrate reduction. These results elucidated the ecological patterns exhibited by microbes under different substrate conditions thereby contributing to our understanding of how substrates shape distinct microcosms in CW systems. This study provides valuable insights for guiding the future construction and management of CWs.
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Carbono , Nitrogênio , Eliminação de Resíduos Líquidos , Águas Residuárias , Áreas Alagadas , Nitrogênio/metabolismo , Carbono/metabolismo , Eliminação de Resíduos Líquidos/métodos , Bactérias/metabolismoRESUMO
Development of green packaging materials is essential to replace traditional plastics in fresh agricultural products preservation. Herein, a coated paper was designed by applying chitosan-based composite coating on paper substrate through a facile automatic coating method. The hydroxypropyl trimethyl ammonium chloride chitosan (HACC) was obtained by direct quaternization via the introduction of hydroxypropyl trimethyl ammonium chloride into the amino group of chitosan, then mixed with polyvinyl alcohol (PVA) to prepare the HACC/PVA coating. Accordingly, the key performance of coated paper were improved ascribed to the synergy effect of HACC/PVA coating and paper substrate. In particular, the minimum oxygen permeability of the coated paper could reach to 0.87 × 10-13 cm3·cm/cm2·s·Pa, and the optimum water vapor permeability and tensile strength of HACC/PVA coated paper was 0.75 × 10-12 g·cm/cm2·s·Pa and 6.88 kN/m, respectively. The coated paper used as packaging material not only reduced weight loss ratio of strawberry and greengrocery, but also exhibited lower chromatic aberration and better sensory evaluation, indicating a favorable effect on fruit and vegetable storage. Taken together, the designed eco-friendly coated paper has shown tremendous potential for green and biodegradable packaging material in agricultural products preservation.
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The widespread use of microplastics (MPs) has led to an increase in their discharge to wastewater treatment plants. However, the knowledge of impact of MPs on macro-performance and micro-ecology in simultaneous nitrification, denitrification, and phosphorus removal (SNDPR) systems is limited, hampering the understanding of potential risks posed by MPs. This study firstly comprehensively investigated the performance, species interactions, and community assembly under polystyrene (PS) and polyvinyl chloride (PVC) exposure in SNDPR systems. The results showed under PS (1, 10 mg/L) and PVC (1, 10 mg/L) exposure, total nitrogen removal was reduced by 3.38-10.15 %. PS and PVC restrained the specific rates of nitrite and nitrate reduction (SNIRR, SNRR), as well as the activities of nitrite and nitrate reductase enzymes (NIR, NR). The specific ammonia oxidation rate (SAOR) and activity of ammonia oxidase enzyme (AMO) were reduced only at 10 mg/L PVC. PS and PVC enhanced the size of co-occurrence networks, niche breadth, and number of key species while decreasing microbial cooperation by 5.85-13.48 %. Heterogeneous selection dominated microbial community assembly, and PS and PVC strengthened the contribution of stochastic processes. PICRUSt prediction further revealed some important pathways were blocked by PS and PVC. Together, the reduced TN removal under PS and PVC exposure can be attributed to the inhibition of SAOR, SNRR, and SNIRR, the restrained activities of NIR, NR, and AMO, the changes in species interactions and community assembly mechanisms, and the suppression of some essential metabolic pathways. This paper offers a new perspective on comprehending the effects of MPs on SNDPR systems.
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Desnitrificação , Microplásticos , Nitrificação , Fósforo , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Fósforo/metabolismo , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , MicrobiotaRESUMO
Non-alcoholic fatty liver disease (NAFLD) is characterized by triglyceride (TG) accumulation in hepatocytes. Very low density lipoprotein (VLDL) is a major secretory product of the liver that transports endogenously synthesized TG. Disrupted VLDL secretion may contribute to the accumulation of TG in hepatocytes. ApoB100 (apolipoprotein B100) is a glycoprotein and an essential protein component of VLDL. Its glycosylation may affect VLDL assembly and secretion. However, which glycosyltransferase catalyzes apoB100 glycosylation is unknown. In this study, we cloned the GLT8D2 (glycosyltransferase 8 domain containing 2) gene from HepG2 cells and generated a series of plasmids for in vitro studies of its molecular functions. We discovered that GLT8D2 was localized in the ER, interacted with apoB100, and positively regulated the levels of apoB100 protein in HepG2 cells. Based on these results, we propose that GLT8D2 is a glycosyltransferase of apoB100 that regulates apoB100 levels in hepatocytes.