Sustainable upcycling of copper from waste printed circuit boards with the assistance of tannic acid and Fe3+ to a magnetic heterogeneous catalyst.

The recovery and upcycling of metals from electronic waste into functional materials for wastewater treatment is a win-win strategy for simultaneously realizing electronic waste recycling and wastewater purification. This study focused on converting Cu from waste printed boards (PCBs), a common Cu-rich electronic waste, into CuFe2O4 supported on a mesoporous carbon framework (PCFT) with the assistance of Fe3+ and tannic acid (TA). Compared to the PCF prepared without TA, the resulting PCFT exhibited excellent magnetic properties, high crystallinity, lower interfacial transfer resistance, more abundant oxygen vacancies (OV), and lower metal leaching. Moreover, PCFT can serve as a superior heterogeneous catalyst to activate peroxymonosulfate to remove reactive brilliant blue KN-R from wastewater, and its catalytic activity was markedly higher than that of CFT synthesized with Cu(NO3)2·3H2O, which may be due to its higher specific surface area and more abundant OV. The combined results of scavenging experiments, electron paramagnetic resonance analysis, and electrochemical measurements implied that both radical and nonradical processes promoted the elimination of KN-R; however, •OH and SO4•- were not the major contributors. Furthermore, the PCFT exhibited high adaptability to pH and water matrices, confirming its practical application potential. These findings provide a novel strategy for the upcycling of metals from electronic waste.

How can the microbial community in watershed sediment maintain its resistance in the presence of shifting antibiotic residuals?

The widespread presence of antibiotics in global watershed environments poses a serious threat to public health and ecosystems. It is essential to examine the resistance of microbial communities in watershed environments in response to shifting antibiotic residues. Sediment samples were collected from seven sites across a watershed, encompassing surface sediment (0-10 cm) and bottom sediment (30-40 cm) depths. The aim was to replicate exposure scenarios to different antibiotics (oxytetracycline (OTC) and sulfadiazine (SD)) at varying concentrations (0, 10, and 100 µg/L) in sediment overlying water, within controlled laboratory settings. The study findings revealed significant variations in the microbial community structure of sediments between different treatments, with distinct differences observed in the upper stream and top sediment layers compared to the sediments located downstream and in the bottom layers. After the introduction of antibiotics, a significant decrease in microbial nodes was observed in the genus-level co-occurrence network analysis of the bottom sediment layer, particularly in the OTC treatment groups. In contrast, the downstream region displayed more robust correlations among the top 20 genera than the upstream area. There was no significant variance observed in the expression of Antibiotic resistance genes (ARGs), consisting of tetracycline resistance genes (tetC, tetG, tetM, tetW, and tetX) and sulfonamide resistance genes (sul1, sul2, and sul3), between sediments in the top and bottom layers. Nevertheless, downstream samples exhibited significantly higher levels of ARGs when compared to upstream samples. Network correlation analysis indicated notably lower correlations between ARGs and bacterial genera in sediments from upstream or surface layers compared to those in downstream or deeper layers. Moreover, correlations in the sediments from surface layers and upstream regions showed a decreasing trend with increasing SD exposure concentrations, while those in deeper layers and downstream areas remained relatively stable. The presence of antibiotics notably enhanced the correlation between sediment properties and ARGs, particularly emphasizing associations with total carbon, nitrogen, and sulfur content. However, the introduction of SD and OTC resulted in a decrease in the influence of these sediment factors on microbial community functions related to sulfur and nitrogen metabolism, as indicated by KEGG (Kyoto Encyclopedia of Genes and Genomes) annotation. The research provided empirical evidence on how microbial resistance responds to changes in antibiotics in sediment samples taken from various depths and locations within a watershed. It emphasized the urgent need for heightened awareness of the movement and alteration of antibiotic resistance patterns in watershed ecosystems.

Microbial community structure and antibiotic resistance profiles in sediments with long-term aquaculture history.

The aim of this investigation was to examine the microbial populations and their resistance patterns towards antibiotics, including the impact of nitrogen metabolism in response to the reintroduction of antibiotics, as well as the presence of resistance genes in sediments from shrimp ponds that have been utilized for extended periods of 5, 15, and over 30 years. Results showed that the sediments exhibited a high prevalence of Proteobacteria, Bacteroidetes, Planctomycetes, Chloroflexi, and Oxyphotobacteria as the most abundant bacterial phyla, accounting for 70.35-77.43% of the total bacterial community. The five most abundant phyla of fungi detected in all sediments, namely Rozellomycota, Ascomycota, Aphelidiomycota, Basidiomycota, and Mortierellomycota, constituted 24.26-32.54% of the total fungal community. It was highly probable that the Proteobacteria and Bacteroidetes phyla serve as the primary reservoir of antibiotic-resistant bacteria (ARB) in the sediment, which included various genera like Sulfurovum, Woeseia, Sulfurimonas, Desulfosarcina, and Robiginitalea. Among these genera, Sulfurovum appeared to be the most widespread in the sediment of aquaculture ponds that have been in operation for more than three decades, while Woeseia dominated in ponds that have been recently reclaimed and have a 15-year aquaculture history. Antibiotic resistance genes (ARGs) were categorized into seven distinct groups according to their mechanism of action. The prevalence of multidrug-resistant ARGs was found to be the highest among all types, with an abundance ranging from 8.74 × 10-2 to 1.90 × 10-1 copies per 16S rRNA gene copies. The results of a comparative analysis of sediment samples with varying aquaculture histories indicated that the total relative abundance of ARGs was significantly diminished in sediment with a 15-year aquaculture history as opposed to sediment with either a 5-year or 30-year aquaculture history. Another assessment of antibiotic resistances in aquaculture sediments involved an examination of the effects of reintroducing antibiotics on nitrogen metabolism processes. The findings revealed that the rates of ammonification, nitrification, and denitrification in the sediment with a history of 5 years and 15 years, decreased as the concentration of oxytetracycline increased from 1 to 300, and 2000 mg/kg, and inhibitory effects were found to be less pronounced in sediments with a 5-year history compared to those with a 15-year history. In contrast, oxytetracycline exposure led to a significant decrease in the rates of these processes in aquaculture pond sediments with a >30 years of aquaculture history across all the concentrations tested. The emergence and dissemination of antibiotic resistance profiles in aquaculture environments requires attention in future aquaculture management.

Waste eggshell-supported CuO used as heterogeneous catalyst for reactive blue 19 degradation through peroxymonosulfate activation (CuO/eggshell catalysts activate PMS to degrade reactive blue 19).

Advanced oxidation processes play an important role in the removal of organic pollutants from wastewater, in which it is essential to develop an eco-friendly, effective, stable, and inexpensive catalyst. Herein, waste eggshell-supported copper oxide (CuO/eggshell) was synthesized via a facile method and employed as peroxymonosulfate (PMS) activator for the elimination of reactive blue 19 (RB19). CuO/eggshell exhibited high degradation efficiency of RB19 (approximately 100%) by activation of PMS under the optimum conditions of 20 mg/L RB19, 0.2 g/L CuO/eggshell, 0.36 mM PMS, and initial pH 7.12 within 20 min. In addition, the effects of catalyst dosage, PMS concentration, initial pH, inorganic ions, and humic acid on RB19 degradation were investigated. Scavenging experiments and electron paramagnetic resonance revealed that multiple reactive oxygen species, including sulfate radicals (SO4·-), hydroxyl radicals (·OH), superoxide radicals (O2·-), and singlet oxygen (1O2), contributed to RB19 degradation, and 1O2 played a dominant role. Finally, a possible PMS activation mechanism was proposed. This study suggests that loading catalytically active components onto waste eggshell is eco-friendly and effective for enhancing the degradation of dyes from wastewater.

Porous Core/Dense Shell PLA Microspheres Embedded with High Drug Loading of Bupivacaine Crystals for Injectable Prolonged Release.

Objective of the study was to design an injectable microsphere preparation with high drug loading of bupivacaine for prolonged release and local anesthetic. PLA or PLGA was used as the biodegradable matrix material to fabricate microspheres with the o/w emulsification-solvent evaporation method. The characterization of bupivacaine microspheres was observed by SEM, DSC, and XRPD. The microsphere preparation and extended drug release, as well as the plasma drug concentration and sciatic nerve blockade after injection of the microsphere formulation to rats were investigated. High drug-loading microspheres of more than 70% were successfully obtained with extended drug release over 5 days in vitro depending on the type of matrix and the feed ratio of drug to polymer. SEM, DSC, and XRPD results verified a novel microsphere structure characterized as the porous core composed of PLA material and form II bupivacaine crystals and dense shell formed of PLA layer. The mechanism that bupivacaine was dissolved inside the microsphere and diffused across the dense shell was suggested for drug release in vitro. The optimized PLA microsphere formulation showed low and steady plasma drug concentration over 5 days and prolonged duration of sensory and motor blockade of sciatic nerve lasted more than 3 days. Results indicated that the porous core-shell structure of PLA microsphere formulation would provide enormous potential as an injectable depot for locally prolonged delivery of bupivacaine and control of postoperative pain.

Cyclocarya paliurus for Phytomanagement of Lead-Contaminated Soils.

Cyclocarya paliurus seedlings were cultivated in three types of lead (Pb)-contaminated soils with Pb concentration of 305 ± 17 mg/kg (T1), 1964 ± 59 mg/kg (T2) and 3502 ± 107 mg/kg (T3), respectively. The results showed that after 180 days of cultivation, the contents of exchangeable and carbonate-bound Pb fractions significantly decreased in T1 and T2, but increased in T3. The growth indices of C. paliurus seedlings decreased with increasing Pb concentration; however, no difference was found between that in T1 and in Pb-free soil. The Pb concentration in the roots was an order of magnitude higher than that in the stems and in the leaves. The bioconcentration factor (BCF) of the leaves was the lowest among the three tissues investigated, and decreased with the higher concentration of Pb in the soils. These results suggest that C. paliurus can be used as a sustainable and profitable plant for the phytomanagement of Pb-contaminated soil.

A polysaccharide deacetylase from Puccinia striiformis f. sp. tritici is an important pathogenicity gene that suppresses plant immunity.

The cell wall of filamentous fungi, comprised of chitin, polysaccharide and glycoproteins, maintains the integrity of hyphae and protect them from defence responses by potential host plants. Here, we report that one polysaccharide deacetylase of Puccinia striiformis f. sp. tritici (Pst), Pst_13661, suppresses Bax-induced cell death in plants and Pst_13661 is highly induced during early stages of the interaction between wheat and Pst. Importantly, the transgenic wheat expressing the RNA interference (RNAi) construct of Pst_13661 exhibits high resistance to major Pst epidemic races CYR31, CYR32 and CYR33 by inhibiting growth and development of Pst, indicating that Pst_13661 is an available pathogenicity factor and is a potential target for generating broad-spectrum resistance breeding material of wheat. It forms a homo-polymer and has high affinity for chitin and germ tubes of Pst compared with the control. Besides, Pst_13661 suppresses chitin-induced plant defence in plants. Hence, we infer that Pst_13661 may modify the fungal cell wall to prevent recognition by apoplastic surveillance systems in plants. This study opens new approaches for developing durable disease-resistant germplasm by disturbing the growth and development of fungi and develops novel strategies to control crop diseases.

Enhanced Antitumor Efficacy of Curcumin-Loaded PLGA Nanoparticles Coated with Unique Fungal Hydrophobin.

Modifications to the surface chemistry, charge, and hydrophilicity/hydrophobicity of nanoparticles are applicable approaches to the alterations of the in vivo fate of intravenously administered nano-sized drug carriers. The objective of this study is to investigate the in vitro and in vivo antitumor efficacies of curcumin PLGA nanoparticles in relation to their surface structural modification via self-assembling coating with unique fungal hydrophobin. The hydophobin-coated curcumin PLGA nanoparticles (HPB PLGA NPs) were obtained by simply soaking curcumin-loaded PLGA nanoparticles (PLGA NPs) in aqueous fungal hydrophobin solution. The in vitro drug release behavior of the HPB PLGA NPS was also tested. The cytotoxicity and cellular uptake of these nanoparticles were determined in HepG2, A549, and Hela cell lines using MTT assay method and CLSM observation. The in vivo antitumor activity was evaluated in Hela tumor xenografted mice model. Compared with the PLGA NPs, the size and zeta potential of the nanoparticles were changed after hydrophobin coating, whereas similar in vitro release pattern was observed. The pharmacodynamics study showed prolonged blood retention of both nano-formulations than that of free curcumin, but no significant difference between the hydrophobin coated and uncoated nanoparticles. It was found that HPB PLGA NPs had increased cytotoxicities, higher cellular uptake, and improved antitumor efficacy. Surface modification of nanoparticles via self-assembling of hydrophobin is a convenient and promising method of changing particle surface physiochemical properties and antitumor performances. Further investigations, especially on tissue distribution, were needed to assess the potential application of the hydrophobin self-assembling coating in nano-drug delivery carriers.

Impacts of biochar and oyster shells waste on the immobilization of arsenic in highly contaminated soils.

Soil contamination is a serious problem with deleterious impacts on global sustainability. Readily available, economic, and highly effective technologies are therefore urgently needed for the rehabilitation of contaminated sites. In this study, two readily available materials prepared from bio-wastes, namely biochar and oyster shell waste, were evaluated as soil amendments to immobilize arsenic in a highly As-contaminated soil (up to 15,000 mgAs/kg). Both biochar and oyster shell waste can effectively reduce arsenic leachability in acid soils. After application of the amendments (2-4% addition, w/w), the exchangeable arsenic fraction decreased from 105.8 to 54.0 mg/kg. The application of 2%biochar +2% oyster shell waste most effectively reduced As levels in the column leaching test by reducing the arsenic concentration in the porewater by 62.3% compared with the treatment without amendments. Biochar and oyster shell waste also reduced soluble As(III) from 374.9 ± 18.8 µg/L to 185.9 ± 16.8 µg/L and As(V) from 119.8 ± 13.0 µg/L to 56.4 ± 2.6 µg/L at a pH value of 4-5. The treatment using 4% (w/w) amendments did not result in sufficient As immobilization in highly contaminated soils; high soluble arsenic concentrations (upto193.0 µg/L)were found in the soil leachate, particularly in the form of As(III), indicating a significant potential to pollute shallow groundwater aquifers. This study provides valuable insights into the use of cost-effective and readily available materials for soil remediation and investigates the mechanisms underlying arsenic immobilization in acidic soils.

The anti-melanoma efficiency of the intratumoral injection of cucurbitacin-loaded sustained release carriers: in situ-forming implants.

Our previous studies revealed that the PLGA-based particulate systems loaded with cucurbitacin showed limited anti-melanoma efficiency in xenograft animal models after intratumoral injection, which was due to the undesirable initial burst release and the leakage of the particulate carriers from the injection site through the pinhole. In this paper, two categories of in situ-forming implants (ISFIs) for intratumoral injection, PLGA ISFIs and SAIB ISFIs, were systemically evaluated for their potentials for on solid tumor treatment via intratumoral injection. The in vitro drug release profiles of these two ISFIs were different due to the different sol-gel transition properties. The pharmacodynamics results revealed that SAIB ISFIs displayed obvious therapeutic efficiencies to melanoma, and multi-points injection of SASIB ISFIs displayed better efficiency than single-point injection. The different sol-gel transition properties and mechanism for PLGA ISFIs and SAIB ISFIs affected both the drug release and strongly impacted the pharmacokinetic parameters and pharmacodynamic effectiveness. Also, the adhesive property of SAIB to the local tissue could extend the retention and inhibit the leakage of the SAIB ISFIs, thus enhanced the anticancer effectiveness. Comparison of the various intratumoral injection systems, appropriate drug release profiles (lower initial burst and steady release) and good retention (minimum leakage from the injection site) would benefit to the antitumor effects of the intratumoral depots.

Self-assembled micelles composed of doxorubicin conjugated Y-shaped PEG-poly(glutamic acid)2 copolymers via hydrazone linkers.

In this work, micelles composed of doxorubicin-conjugated Y-shaped copolymers (YMs) linked via an acid-labile linker were constructed. Y-shaped copolymers of mPEG-b-poly(glutamate-hydrazone-doxorubicin)2 and linear copolymers of mPEG-b-poly(glutamate-hydrazone-doxorubicin) were synthesized and characterized. Particle size, size distribution, morphology, drug loading content (DLC) and drug release of the micelles were determined. Alterations in size and DLC of the micelles could be achieved by varying the hydrophobic block lengths. Moreover, at fixed DLCs, YMs showed a smaller diameter than micelles composed of linear copolymers (LMs). Also, all prepared micelles showed sustained release behaviors under physiological conditions over 72 h. DOX loaded in YMs was released more completely, with 30% more drug released in acid. The anti-tumor efficacy of the micelles against HeLa cells was evaluated by MTT assays, and YMs exhibited stronger cytotoxic effects than LMs in a dose- and time-dependent manner. Cellular uptake studied by CLSM indicated that YMs and LMs were readily taken up by HeLa cells. According to the results of this study, doxorubicin-conjugated Y-shaped PEG-(polypeptide)2 copolymers showed advantages over linear copolymers, like assembling into smaller nanoparticles, faster drug release in acid, which may correspond to higher cellular uptake and enhanced extracellular/intracellular drug release, indicating their potential in constructing nano-sized drug delivery systems.

Tannic acid-assisted upcycling of Cu from waste printed circuit boards to an efficient peroxymonosulfate catalyst for the degradation of organic pollutants.

The recovery of metals from solid waste for use as heterogeneous catalysts to activate peroxymonosulfate (PMS) for organic wastewater treatment is a promising, environmentally friendly and economical strategy. Herein, we present a facile and versatile strategy for upcycling copper (Cu) from waste printed circuit boards (PCBs) to Cu oxides supported on a three-dimensional carbon framework (10PCBs-Cu-TA) with the aid of tannic acid (TA). Compared to the PCBs-Cu synthesized without TA, introducing TA into 10PCBs-Cu-TA reduced Cu leaching, enhanced crystallinity, promoted electron transfer, and increased the number of oxygen vacancies. Moreover, 10PCBs-Cu-TA exhibited superior catalytic activity in activating PMS for the degradation of reactive brilliant blue KN-R, exceeding the activity of 10Cu-TA prepared using commercial Cu(NO3)2·3H2O. This enhanced performance may be attributed to the higher specific surface area and oxygen vacancies of 10PCBs-Cu-TA. The 10PCBs-Cu-TA/PMS system also exhibited broad catalytic universality and adaptability to various contaminants and water matrices. Quenching experiments, electron paramagnetic resonance analysis, and electrochemical measurements indicated that radical and non-radical processes jointly contributed to KN-R degradation. The proposed strategy for upcycling Cu from waste PCBs into functional materials provides novel insights into the utilization of solid waste and the development of PMS activators.

The application of organic selenium (SeMet) improve the photosynthetic characteristics, yield and quality of hybrid rice.

Rice is an important food in the world, and selenium (Se) is a necessary trace element for the human. So the effects of selenomethionine (SeMet) on photosynthetic capacity, yield and quality of rice at different stages were studied. The results show that SeMet can increase the Ppotosynthetic capacity of rice leaves during each growth stage, the effect of 5 mg/L SeMet treatment was the most significant. At the mature stage of rice, SeMet significantly increased rice yield and total plant biomass, 7.5and 5 mg/L SeMet treatments had the most significant effects, respectively. In addition, SeMet significantly improved the content of Se and processing quality of rice, decreased chalkiness, inhibited amylose synthesis, and optimized flavor. The above indices showed the best results after treatment with 5 mg/L SeMet. It is hoped that this study will provide a theoretical basis for the application of organic selenium in rice production.

Arsenic behavior in soil-plant system under the manure application with the combination of antibiotic and roxarsone.

Limited attention has been given to the interaction between antibiotics and arsenic in the soil-plant system. In this investigation, Medicago sativa seedlings were grown in soil treated with cow manure containing oxytetracycline (OTC) or sulfadiazine (SD), as well as arsenic (introduced through roxarsone, referred to as ROX treatment). The study revealed a notable increase in As(III) and dimethylarsinic acid (DMA(V)) levels in rhizosphere soils and plant root tissues as arsenic contamination intensified in the presence of antibiotics, while concentrations of As(V) and monomethylarsonic acid (MMA(V)) decreased. Conversely, elevated antibiotic presence resulted in higher levels of As(V) but reduced DMA concentrations in both rhizosphere soils and plant root tissues in the presence of arsenic. The arsenic biotransformation gene aioA was inhibited by arsenic contamination when antibiotics were present, and suppressed by antibiotic contamination in the presence of arsenic, especially in SD treatments, resulting in reduced expression levels at higher SD concentrations. Conversely, the arsM gene exhibited consistent upregulation under all conditions. However, its expression was found to increase with higher concentrations of ROX in the presence of antibiotics, decrease with increasing SD concentrations, and initially rise before declining with higher levels of OTC in the presence of arsenic. Bacterial genera within the Proteobacteria phylum, such as Geobacter, Lusitaniella, Mesorhizobium, and Methylovirgula, showed significant co-occurrence with both aioA and arsM genes. Correlation analysis demonstrated associations between the four arsenic species and the two arsenic biotransformation genes, emphasizing pH as a critical factor influencing the transformation and uptake of different arsenic species in the soil-plant system. The combined stress of antibiotics and arsenic has the potential to modify arsenic behavior and associated risks in soil-plant systems, highlighting the necessity of considering this interaction in future research endeavors.

Anti-Melanoma Activity of Single Intratumoral Injection of ZnPc Micelles Mixed With in situ Gel in B16 Bearing Mouse.

Photodynamic therapy (PDT) is a potential treatment strategy for melanoma. As a second-generation photosensitizer, Zinc phthalocyanine (ZnPc) has many advantages for anti-tumor PDTs, such as strong absorption in the red and near infrared regions, high photo and chemical stability, etc. However, ZnPc has a poor water solubility and is apt to aggregate due to the π-π interaction between molecules, which limits its applications. In this study, various solvents and surfactants were screened for dissolving ZnPc and preparing ZnPc@SDC-TPGS micelle and thermosensitive in situ gel. After the cytotoxic effects of thermosensitive gels on PDT were tested, the antitumor effects on PDT of them in mice by intratumoral injection were evaluated, including body weight, and tumor weight, volume and morphology. The cell death pathway and the relationship of reactive oxygen species yield with apoptotic rate of tumor cells induced by ZnPc in situ gel were investigated. The results were that N-methyl-pyrrolidone (NMP) mixed with 2 % SDC and aqueous solution containing 2 % TPGS and 2 % SDC were used to synthesize ZnPc@SDC-TPGS micelle and the thermosensitive in situ gel. The cytotoxic effects of thermosensitive gels showed good tumor suppression of ZnPc@SDC-TPGS in situ gel and no toxicity of the blank gel. Intratumoral injection in situ gel containing 3 µg ZnPc under irradiation demonstrated good tumor inhibition in mice with melanoma. Apoptosis has been established as the primary pathway of cell death, and the production of reactive oxygen species (ROS) plays a crucial role in cellular apoptosis induced by ZnPc@SDC-TPGS in situ gel. In conclusion, the intratumoral injection of ZnPc@SDC-TPGS thermosensitive in situ gel provides a promising local treatment option for melanoma.

Bacteroides fragilis ubiquitin homologue drives intraspecies bacterial competition in the gut microbiome.

Interbacterial antagonism and associated defensive strategies are both essential during bacterial competition. The human gut symbiont Bacteroides fragilis secretes a ubiquitin homologue (BfUbb) that is toxic to a subset of B. fragilis strains in vitro. In the present study, we demonstrate that BfUbb lyses certain B. fragilis strains by non-covalently binding and inactivating an essential peptidyl-prolyl isomerase (PPIase). BfUbb-sensitivity profiling of B. fragilis strains revealed a key tyrosine residue (Tyr119) in the PPIase and strains that encode a glutamic acid residue at Tyr119 are resistant to BfUbb. Crystal structural analysis and functional studies of BfUbb and the BfUbb-PPIase complex uncover a unique disulfide bond at the carboxy terminus of BfUbb to mediate the interaction with Tyr119 of the PPIase. In vitro coculture assays and mouse studies show that BfUbb confers a competitive advantage for encoding strains and this is further supported by human gut metagenome analyses. Our findings reveal a previously undescribed mechanism of bacterial intraspecies competition.

Antibiotics and their associations with antibiotic resistance genes and microbial communities in estuarine and coastal sediment of Quanzhou Bay, Southeast China.

The antibiotic concentrations spanned from 11.2 to 173.8 ng/g, with quinolones and tetracyclines being observed to be prevalent. The amount of microbial biomass as determined by Phospholipid fatty acid (PLFA) ranged from 2.92 to 10.99 mg kg-1, with G- bacteria dominating. A total of 254 distinct ARGs and 10 MEGs were identified, with multidrug ARGs having the highest relative abundance (1.18 × 10-2 to 3.00 × 10-1 copies/16S rRNA gene copies), while vancomycin and sulfonamide resistance genes were the least abundant. Results from canonical-correlation analyses combined with redundancy analysis indicated that macrolides were significantly related to the shifts of microbial community structure in sediments, particularly in G+ bacteria that were more sensitive to antibiotic residues. It was observed that sulfonamide ARGs had a greater correlation with residual antibiotics than other ARGs. This study provided a field evidence that multiple residual antibiotics from coastal sites could cause fundamental shifts in microbial community and their associated ARGs.

Adaptation of Rhizosphere Microbial Communities to Continuous Exposure to Multiple Residual Antibiotics in Vegetable Farms.

The constant application of manure-based fertilizers in vegetable farms leads to antibiotic residue accumulation in soils, which has become a major stressor affecting agroecosystem stability. The present study investigated the adaptation profiles of rhizosphere microbial communities in different vegetable farms to multiple residual antibiotics. Multiple antibiotics, including trimethoprim, sulfonamides, quinolones, tetracyclines, macrolides, lincomycins, and chloramphenicols, were detected in the vegetable farms; the dominant antibiotic (trimethoprim) had a maximum concentration of 36.7 ng/g. Quinolones and tetracyclines were the most prevalent antibiotics in the vegetable farms. The five most abundant phyla in soil samples were Proteobacteria, Actinobacteria, Acidobacteria, Chloroflexi and Firmicutes, while the five most abundant phyla in root samples were Proteobacteria, Actinobacteria, Bacteroidetes, Firmicutes and Myxococcota. Macrolides were significantly correlated with microbial community composition changes in soil samples, while sulfonamides were significantly correlated with microbial community composition changes in root samples. Soil properties (total carbon and nitrogen contents and pH) influenced the shifts in microbial communities in rhizosphere soils and roots. This study provides evidence that low residual antibiotic levels in vegetable farms can shift microbial community structures, potentially affecting agroecosystem stability. However, the degree to which the shift occurs could be regulated by environmental factors, such as soil nutrient conditions.

Robustness optimization for rapid prototyping of functional artifacts based on visualized computing digital twins.

This study presents a robustness optimization method for rapid prototyping (RP) of functional artifacts based on visualized computing digital twins (VCDT). A generalized multiobjective robustness optimization model for RP of scheme design prototype was first built, where thermal, structural, and multidisciplinary knowledge could be integrated for visualization. To implement visualized computing, the membership function of fuzzy decision-making was optimized using a genetic algorithm. Transient thermodynamic, structural statics, and flow field analyses were conducted, especially for glass fiber composite materials, which have the characteristics of high strength, corrosion resistance, temperature resistance, dimensional stability, and electrical insulation. An electrothermal experiment was performed by measuring the temperature and changes in temperature during RP. Infrared thermographs were obtained using thermal field measurements to determine the temperature distribution. A numerical analysis of a lightweight ribbed ergonomic artifact is presented to illustrate the VCDT. Moreover, manufacturability was verified based on a thermal-solid coupled finite element analysis. The physical experiment and practice proved that the proposed VCDT provided a robust design paradigm for a layered RP between the steady balance of electrothermal regulation and manufacturing efficacy under hybrid uncertainties.

Impacts of Eucalyptus plantation on soil and water losses in a typical small watershed in mountainous area of southern China.

Unreasonable exploitation of artificial forest causes severe soil erosion in the mountainous areas of sou-thern China. The spatial-temporal variations of soil erosion in typical small watershed with artificial forest has signifi-cant implications for artificial forest exploitation and sustainable development of mountainous ecological environment. In this study, we used revised universal soil loss equation (RUSLE) and geographic information system (GIS) to evaluate the spatial and temporal variations of soil erosion and its key drivers of Dadingshan watershed in mountainous area of western Guangdong. The results showed that the erosion modulus was 1948.1 t·km-2·a-1 (belonging to light erosion) in the Dadingshan watershed. However, the spatial variation of soil erosion was substantial, with variation coefficient of 5.12. The maximal soil erosion modulus was 191127 t·km-2·a-1. Slight erosion (<500 t·km-2·a-1) accounted for 80.6% of the total watershed area. The moderate erosion and above (>2500 t·km-2·a-1) were mainly distributed in young Eucalyptus forest area with less than 30% of the vegetation coverage, which contributed nearly 75.7% of total soil erosion. During 2014-2019, the interannual variations of mean erosion of Dadingshan catchment was modest, but the spatial variation of soil erosion was large. Vegetation cover, slope, and rainfall were key drivers of such variation. The destruction of natural vegetation resulted by plantation exploitation was the primary cause of soil erosion in afforestation areas. Soil erosion significantly increased with the increases of slope gradient in the young forest area, which was aggravated by extreme rainfall. However, soil erosion gradually decreased with the increases of the age of Eucalypt plantation. Therefore, the hot spot of soil erosion was young forest areas of Eucalypt plantation with slope >25°, and the key period for soil erosion control was the first 2-3 years after Eucalyptus planting. We suggested that reasonable afforestation measures should be used in area with >25° slopes, and that the destruction of natural vegetation should be avoided on hillslope with >35° slope gradient. The road construction standards and forest management should be further improved to address the challenge of extreme rainfalls.