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The current study replicated an earlier investigation by Bouwer and van der Veen (2023) where 10 Grade 5 and 6 classrooms in the Netherlands (210 students) were randomly assigned to a treatment or control condition, with treatment students evidencing improvements in the quality of their essays after practice writing argumentative essays, reading and discussing them with a small group of peers, and revising each essay based on the discussion that ensued. In the present study, 12 Grade 2 to 4 classrooms in Türkiye (383 students) were randomly assigned to this write, talk, and rewrite dialogic treatment or to a control condition. Students in the control condition practiced planning and writing the same four argumentative essays as treatment students did during the experiment, and each of these essays was shared with peers (time spent in both conditions was comparable). Control students did not, however, discuss their essay with peers or use such feedback to revise them as was done by students in the write, talk, and rewrite dialogic treatment. When the nested nature of the data and pretest scores were held constant, the quality of the argumentative posttest essays produced by students in the treatment condition evidenced greater improvement than essays written by control students. The same outcome was obtained for the length of essays (number of words) when the nested nature of the data and pretest scores were held constant. This investigation provided evidence that the write, talk, and rewrite dialogic intervention tested by Bouwer and van der Veen (2023) was effective in improving the argumentative writing of even younger students in a different country. Implications for research and practice are provided. [ABSTRACT FROM AUTHOR]

In the process of electroreduction of carbon dioxide (eCO2RR) to multi‐carbon (C2+) products, it is imperative to enhance the concentration of key intermediate species on the catalyst surface. The utilization of micro‐nano reactors to achieve confinement effects has been widely observed in various catalytic reactions, yet it has seldom been employed in eCO2RR. Here, we present a novel nanoreactor composed of stacked CuS nanosheets for eCO2RR to C2+ products. In comparison to catalyst comprising of nanosheet with open space, the C−C coupling within this confined nanospace is significantly enhanced, resulting in the increase of Faraday efficiency (FE) of C2+ products to 53 %. In situ infrared (IR) spectroscopy reveals the confinement and enrichment of key intermediate by the nanoreactor. Our research findings demonstrate that a meticulously designed nanoreactor can elevate the selectivity of C2+ products, thereby aiding in the design of eCO2RR catalysts. [ABSTRACT FROM AUTHOR]

In this study, we developed a rapid and effective method for enriching the culture of nitrifying bioflocs (NBF) from aquacultural brackish water. The self-designed mixotrophic mediums with a single or mixed addition of sodium acetate, sodium citrate, and sucrose were used to investigate the enrichment process and nitrification efficiency of NBF in small-scale reactors. The results showed that NBF with an MLVSSs from 1170.4 mg L−1 to 2588.0 mg L−1 were successfully enriched in a period of less than 16 days. The citrate group performed the fastest enrichment time of 10 days, while the sucrose group had the highest biomass of 2588.0 ± 384.7 mg L−1. In situ testing showed that the highest nitrification efficiency was achieved in the citrate group, with an ammonia oxidation rate of 1.45 ± 0.34 mg N L−1 h−1, a net nitrification rate of 2.02 ± 0.20 mg N L−1 h−1, and a specific nitrification rate of 0.72 ± 0.14 mg N g−1 h−1. Metagenomic sequencing revealed that Nitrosomonas (0.0~1.0%) and Nitrobacter (10.1~26.5%) were dominant genera for AOB and NOB, respectively, both of which had the highest relative abundances in the citrate group. Linear regression analysis further demonstrated significantly positive linear relations between nitrification efficiencies and nitrifying bacterial genera and gene abundance in NBF. The results of this study provide an efficient enrichment culture method of NBF for the operation of biofloc technology aquaculture systems, which will further promote its wide application in modern intensive aquaculture. [ABSTRACT FROM AUTHOR]

Although previous studies have investigated the occurrence of antibiotic resistance genes (ARGs) in aquaculture, few have monitored the concentrations and propagation of ARGs in biological tissues or investigated the key factors influencing their spread in aquaculture. This study investigated the concentration, propagation, and distribution of ARGs and bacterial communities in water sources, pond water, and tilapia tissues, and their key influencing factors, in a typical tilapia farm. ErmF, sul1, and sul2 were the dominant ARGs with high concentrations. The total concentrations of ARGs (TCAs) in tilapia tissues decreased in the following order: stomach > scales > intestine > gills (P < 0.05). Redundancy analysis and multiple linear regression revealed that suspended solids (SS) and chemical oxygen demand (COD) were positively correlated with the dominant ARGs ermF sul2, and the TCAs (P < 0.05); additionally, Chloroflexi and Bacteroidetes in tilapia aquaculture water were positively correlated with the dominant ARGs ermF and sul2, as well as the TCAs (P < 0.05). This study suggests that SS and COD were the key factors driving the distribution and spread of ARGs in tilapia aquaculture water. Additionally, Chloroflexi and Bacteroidetes were the key bacterial flora affecting the propagation of ARGs in tilapia aquaculture systems. [ABSTRACT FROM AUTHOR]

In this study, we examined the relation of observed classroom practices to language and literacy achievement and the moderation of this relation for students from pre-K to sixth grade. A total of 136 studies (N = 107,882 participants) met the inclusion criteria, of which 108 studies were included for meta-analysis and the other 28 studies were narratively synthesized. The average zero-order (r =.12) and partial correlations (rp =.04) were statistically significant but weak in magnitude. The relation was slightly weaker in upper than in lower grade levels, and stronger for observations capturing macro quality and instructional dimension than those capturing micro measurement and emotional or structural dimension, respectively. The relation did not vary by observation duration, frequency, adopted statistical approach, or type of covariates. Taken together with the narrative synthesis, the results highlight the complex nature of classroom observation and a need for more classroom research, particularly on higher grade levels. [ABSTRACT FROM AUTHOR]

Single atom alloy (SAA) catalysts have been recently explored for promotion of various heterogeneous catalysis, but it remains unexplored for selective electrocatalytic reduction of carbon dioxide (CO2) into multi‐carbon (C2+) products involving C−C coupling. Herein we report a single‐atomic Bi decorated Cu alloy (denoted as BiCu‐SAA) electrocatalyst that could effectively modulate selectivity of CO2 reduction into C2+ products instead of previous C1 ones. The BiCu‐SAA catalyst exhibits remarkably superior selectivity of C2+ products with optimal Faradaic efficiency (FE) of 73.4 % compared to the pure copper nanoparticle or Bi nanoparticles‐decorated Cu nanocomposites, and its structure and performance can be well maintained at current density of 400 mA cm−2 under the flow cell system. Based on our in situ characterizations and density functional theory calculations, the BiCu‐SAA is found to favor the activation of CO2 and subsequent C−C coupling during the electrocatalytic reaction, as should be responsible for its extraordinary C2+ selectivity. [ABSTRACT FROM AUTHOR]

Single atom alloy (SAA) catalysts have been recently explored for promotion of various heterogeneous catalysis, but it remains unexplored for selective electrocatalytic reduction of carbon dioxide (CO2) into multi‐carbon (C2+) products involving C−C coupling. Herein we report a single‐atomic Bi decorated Cu alloy (denoted as BiCu‐SAA) electrocatalyst that could effectively modulate selectivity of CO2 reduction into C2+ products instead of previous C1 ones. The BiCu‐SAA catalyst exhibits remarkably superior selectivity of C2+ products with optimal Faradaic efficiency (FE) of 73.4 % compared to the pure copper nanoparticle or Bi nanoparticles‐decorated Cu nanocomposites, and its structure and performance can be well maintained at current density of 400 mA cm−2 under the flow cell system. Based on our in situ characterizations and density functional theory calculations, the BiCu‐SAA is found to favor the activation of CO2 and subsequent C−C coupling during the electrocatalytic reaction, as should be responsible for its extraordinary C2+ selectivity. [ABSTRACT FROM AUTHOR]

Given the widespread use of commercial probiotics in aquaculture, it is important to evaluate the quality and environmental effects of these additives. Here, the effects of a Bacillus probiotic compound, BG4, on Penaeus vannamei survival rate, water quality factors, and microbial communities were assessed. An analysis of the BG4 powder confirmed the content of probiotic bacteria: 50.2% Bacillus licheniformis, 48.4% Bacillus subtilis, and 1.4% Bacillus amyloliquefaciens, consistent with the information on the product packaging. The effective bacterial quantity (1.1 × 109 CFU/g) was higher than that indicated on the product label (2 × 108 CFU/g). BG4 was added to a sterilized aquaculture water system, according to the indicated bacterial quantity; after 7 days, the maximum ammonia nitrogen, phosphate, and chemical oxygen demand degradation rates were 36.3%, 28.9%, and 15.2%, respectively. In the shrimp culture experiment, the survival rate of P. vannamei and water quality did not differ significantly between the BG4 and control groups. The bacterial quantity and high-throughput sequencing results indicated that Bacillus content in BG4 group decreased continuously from 3.5 × 104 CFU/mL to 6.9 × 102 CFU/mL. To ensure the desired effect of probiotics in commercial aquaculture applications, additional quality evaluations and scientific assessments are needed. [ABSTRACT FROM AUTHOR]

Microcystis aeruginosa is reported to cause cyanobacterial blooms in shrimp breeding ponds, which can result in significant shrimp mortality. However, the toxic effects of M. aeruginosa on Litopenaeus vannamei are still not completely understood. In this paper, the toxicity of M. aeruginosa cells to L. vannamei was examined, and the toxic components in the cells were analyzed through high-pressure liquid chromatography (HLPC). In addition, the immune response of shrimp to the M. aeruginosa cell extract was assessed by measuring the activity of immune-related enzymes, as well as the transcription of the relevant genes. The results showed that M. aeruginosa cells, extract and cell-free cultured medium resulted in a 100%, 98.3%, and 1.7% mortality rate in shrimp, respectively. HPLC analysis results revealed the presence of microcystin-LR (MC-LR) at a concentration of 190.40 mg/kg of cells. In addition, the activity and gene transcription of two immune related enzymes, SOD and LZM, were both significantly reduced in shrimp hepatopancreas (p < 0.05) after injection with extract. However, reduced glutathione (GSH) content was slightly increased, but the ratio of GSH to GSSG decreased. The transcription of gst gene function as detoxification, was significantly downregulated (p < 0.05). The results demonstrated that M. aeruginosa cell extract was highly toxic to L. vannamei, and exerted a negative effect on shrimp immunity including reduction of antioxidant capacity, antibacterial activity and detoxification activity, due to toxins including microcystin-LR. [ABSTRACT FROM AUTHOR]

Sthenoteuthis oualaniensis is an important biological resource in the South China Sea. However, the microbiological characteristics of this squid, especially those of the dwarf-form, are poorly understood. This study was conducted to analyze the microbial community structure and metabolic characteristics of the intestinal and gill tissues of dwarf-form populations of S. oualaniensis. The dwarf-form squids of different sexes and gonadal maturities were collected from South China Sea in spring 2020. Results showed that Mycoplasma was the most dominant group of bacteria in the intestinal samples of the females with immature gonads (FN), females at sexual maturity (FY), and males at sexual maturity (MY) and the second-highest relative abundance group in males with immature gonads (MN). The microbial community structure in squid gills differed from that of intestinal flora. The BD1-7 clade was the dominant genus in gill samples of all groups. Furthermore, the microbial community activities in gills were higher than in intestinal groups, especially FYG. The larger dwarf-form populations had microbial communities with more robust utilization of carbon sources, assessed via average well color development (AWCD). Correlation and redundancy analysis determined that AWCD significantly positively correlated with the relative abundance of BD1-7 clade (p < 0.05). The results indicated that the dominant group of bacteria and microbial community structure were different between the intestinal and gill microbial communities in the dwarf-form S. oualaniensis populations of different sexes and maturities. Moreover, the metabolic potential of the gill microbial community was higher than that of the intestinal microbial community in the dwarf-form populations. [ABSTRACT FROM AUTHOR]

Although increasing attention has been attracted to the study and application of biofloc technology (BFT) in aquaculture, few details have been reported about the bacterial community of biofloc and its manipulation strategy for commercial shrimp production. An 8-week trial was conducted to investigate the effects of three input C/N ratios (8:1, 12:1 and 16:1) on the bacterial community of water biofloc and shrimp gut in a commercial BFT tank system with intensive aquaculture of P. vannamei. Each C/N ratio group had three randomly assigned replicate tanks (culture water volume of 30 m3), and each tank was stocked with juvenile shrimp at a density of 300 shrimp m−3. The tank systems were operated with zero-water exchange, pH maintenance and biofloc control. During the trial, the microbial biomass and bacterial density of water biofloc showed similar variation trends, with no significant difference under respective biofloc control measures for the three C/N ratio groups. Significant changes were found in the alpha diversity, composition and relative abundance of bacterial communities across the stages of the trial, and they showed differences in water biofloc and shrimp gut among the three C/N ratio groups. Meanwhile, high similarity could be found in the composition of the bacterial community between water biofloc and shrimp gut. Additionally, nitrogen dynamics in culture water showed some differences while shrimp performance showed no significant difference among the three C/N ratio groups. Together, these results confirm that the manipulation of input C/N ratio could affect the bacterial community of both water biofloc and shrimp gut in the environment of a commercial BFT system with intensive production of P. vannamei. Moreover, there should be different operations for the nitrogen dynamics and biofloc management during shrimp production process under different C/N ratios. [ABSTRACT FROM AUTHOR]

Introduction: KLRB1 is a gene encoding CD161 expressed in NK cells and some T cell subsets. At present, KLRB1 is believed to affect tumorigenesis and development by regulating the cytotoxicity of NK cells in several cancers. However, there is a lack of systematic reviews of KLRB1 in a variety of malignancies.Objectives: Hence, our research is aimed at providing a relatively comprehensive understanding of the role of KLRB1 in different types of cancer, paving the way for further research on the molecular mechanism and immunotherapy potential of KLRB1.Methods: In this study, we used relevant public databases, including TCGA (The Cancer Genome Atlas), GEO (Gene Expression Omnibus), CCLE (Cancer Cell Line Encyclopedia), GTEx (Genotype Tissue-Expression), and HPA (Human Protein Atlas), to perform a pan-cancer analysis of KLRB1 across 33 types of cancer. We explored the potential molecular mechanism of KLRB1 in clinical prognosis and tumor immunity from the aspects of gene expression, survival status, clinical phenotype, immune infiltration, immunotherapy response, and chemotherapeutic drug sensitivity.Results: KLRB1 was downregulated in 13 cancers while upregulated in kidney cancer. Patients with high expression of KLRB1 have a better prognosis in most types of cancer. Moreover, the KLRB1 expression level is related to TMB and MSI and related to various immune signatures of tumor. The expression of KLRB1 can affect tumor immune cell infiltration. KLRB1 expression level can also affect the sensitivity of chemotherapy drugs.Conclusions: KLRB1 may be a prognostic and immunological biomarker across tumors. At the same time, KLRB1 expression can reflect the sensitivity of cancer patients to chemotherapy drugs. KLRB1 may become a new target for immunotherapy. [ABSTRACT FROM AUTHOR]

As being radiation-free, portable, and capable of repetitive use, ultrasonography is playing an important role in diagnosing and evaluating the COVID-19 Pneumonia (PN) in this epidemic. By virtue of lung ultrasound scores (LUSS), lung ultrasound (LUS) was used to estimate the excessive lung fluid that is an important clinical manifestation of COVID-19 PN, with high sensitivity and specificity. However, as a qualitative method, LUSS suffered from large interobserver variations and requirement for experienced clinicians. Considering this limitation, we developed a quantitative and automatic lung ultrasound scoring system for evaluating the COVID-19 PN. A total of 1527 ultrasound images prospectively collected from 31 COVID-19 PN patients with different clinical conditions were evaluated and scored with LUSS by experienced clinicians. All images were processed via a series of computer-aided analysis, including curve-to-linear conversion, pleural line detection, region-of-interest (ROI) selection, and feature extraction. A collection of 28 features extracted from the ROI was specifically defined for mimicking the LUSS. Multilayer fully connected neural networks, support vector machines, and decision trees were developed for scoring LUS images using the fivefold cross validation. The model with $128\times256$ two fully connected layers gave the best accuracy of 87%. It is concluded that the proposed method could assess the ultrasound images by assigning LUSS automatically with high accuracy, potentially applicable to the clinics. [ABSTRACT FROM AUTHOR]

Gamma-aminobutyric acid (GABA), an important bioactive compound, is synthesized through the decarboxylation of L-glutamate (L-Glu) by glutamate decarboxylase (GAD). The use of lactic acid bacteria (LAB) as catalysts opens interesting avenues for the biosynthesis of food-grade GABA. However, a key obstacle involved in the improvement of GABA production is how to resolve the discrepancy of optimal pH between the intracellular GAD activity and cell growth. In this work, a potential GAD candidate (LpGadB) from Lactobacillus plantarum was heterologously expressed in Escherichia coli. Recombinant LpGadB existed as a homodimer under the native conditions with a molecular mass of 109.6 kDa and exhibited maximal activity at 40°C and pH 5.0. The Km value and catalytic efficiency (kcat/Km) of LpGadB for L-Glu was 21.33 mM and 1.19 mM−1s−1, respectively, with the specific activity of 26.67 μM/min/mg protein. Subsequently, four C-terminally truncated LpGadB mutants (GadBΔC10, GadBΔC11, GadBΔC12, GadBΔC13) were constructed based on homology modeling. Among them, the mutant GadBΔC11 with highest catalytic activity at near-neutral pH values was selected. In further, the GadBΔC11 and Glu/GABA antiporter (GadC) of Lactococcus lactis were co-overexpressed in the host L. lactis NZ3900. Finally, after 48 h of batch fermentation, the engineered strain L. lactis NZ3900/pNZ8149-gadBΔC11C yielded GABA concentration up to 33.52 g/L by applying a two-stage pH control strategy. Remarkably, this is the highest yield obtained to date for GABA from fermentation with L. lactis as a microbial cell factory. Key points • The GadB from L. plantarum was heterologously expressed in E. coli and biochemically characterized. • Deletion of the C-plug in GadB shifted its pH-dependent activity toward a higher pH. • Reconstructing the GAD system of L. lactis is an effective approach for improving its GABA production. [ABSTRACT FROM AUTHOR]

The cobalt metal–organic frameworks (Co-MOFs) were efficiently prepared by ultrasonic-assisted ball milling with low cost, utilizing 1, 3, 5-benzenetricarboxylic acid and cobalt (II) acetate tetrahydrate. The structural characteristics were carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry (TGA), and BET surface areas method. The adsorption of Co-MOFs to Congo Red (CR) was analyzed by Langmuir adsorption isotherm and pseudo-second-order kinetic model. The results showed that the maximum adsorption performance (fitted by Langmuir adsorption isotherm) of the Co-MOFs (with 30 min's synthesis time and 1:1 molar ratio of the raw material) to CR reached 1.76 × 103 mg/g, which is much higher than previous reports. The adsorption experiment reached equilibrium in 30 min. Electrostatic attractions, π–π stacking interactions and pH are considered to play a significant role in the adsorption of Co-MOFs to CR. The adsorption rate of Co-MOFs to CR remains 34% even after it is recycled for the third time. In this paper, the absorption results indicated that Co-MOFs prepared by ultrasonic-assisted ball milling presents a great prospect in the field of CR adsorption. [ABSTRACT FROM AUTHOR]

Intensive and semi-intensive aquaculture systems typically produce high loads of nutrients in their discharge, potentially leading to the development and persistence of harmful algal blooms (HABs). Algicidal bacteria, which inhibit algal growth or kill algal cells, offer a promising biocontrol strategy for reducing HAB. The strain JZBC1, which displays strong algicidal activity against the HAB species Scrippsiella trochoidea, was previously isolated from a dinoflagellate bloom area and identified as Bacillus cereus. In this study, strain JZBC1 was fermented in 2 L and 50 L systems, and then, algicidal properties of JZBC1 fermentation products on the harmful dinoflagellate species S. trochoidea, Prorocentrum micans, and Peridinium umbonatum were examined. Bacterial concentrations of strain JZBC1 reached 6.23 × 109 and 4.47 × 109 CFU/mL in 2 L and 50 L cultures, respectively, and thus effectively expanded during fermentation. Strain JZBC1 showed substantial algicidal activities and a wide algicidal range toward harmful dinoflagellates. Vegetative JZBC1 cells exhibited the best inhibitory and algicidal effects in 1 day. Strain JZBC1 can be formulated into a powder, and the spores can be activated before field application to increase their efficacy. These findings will facilitate large-scale fermentation production and application of Bacillus strain JZBC1 for controlling dinoflagellate blooms in aquaculture ponds. [ABSTRACT FROM AUTHOR]

An SCR catalyst is used as an example to investigate the effects of the washcoat diffusion limitation on the performance of monolith reactors. One-dimensional model and three-dimensional CFD model with and without washcoat diffusion limitation were established. The washcoat diffusion was modeled by using an effective diffusivity in the washcoat region (CFD modeling) and the internal mass transfer coefficient between the interface and the interior of the washcoat (One-dimensional modeling). The results show that numerical models with washcoat diffusion limitation give more accurate NO concentration prediction than the numerical models without washcoat diffusion limitation. Using the ratios of internal mass transfer resistance and reaction resistance to estimate the washcoat diffusion limitation, the correlation between the temperature and the washcoat limitation is discussed. Detailed comparisons of the 1-D model and CFD model are conducted. [ABSTRACT FROM AUTHOR]

Although the prevalence and concentrations of antibiotic resistance genes (ARGs) in aquaculture is receiving increasing scientific interest, there is little understanding of the direct sources and dissemination pathways of ARGs in marine aquaculture-reared organisms. This study investigated the dynamics of ARGs and the bacterial community throughout the rearing period in a typical marine aquaculture farm in South China. The results demonstrated that sul1 and qnrD were predominant in the sediment, and qnrD and qnrA were predominant in the intestinal tracts of shrimps. Network analysis showed that the chemical oxygen demand, total organic carbon, dissolved organic carbon, suspended solids, and total phosphorus were positively correlated with the predominant ARGs. The results of the network and source tracking analyses indicate that environmental factors and the bacterial community may drive the dissemination of ARGs dissemination in the environment and in shrimp reared by marine aquaculture, and sediment is the most direct and important medium in this dissemination. These results aid in improving our understanding of the sources, level, and dissemination of ARGs in marine aquaculture. [ABSTRACT FROM AUTHOR]

Purpose: Laboratory incubation experiments using 15N stable isotope labeling and acetylene suppression techniques were conducted to compare the autotrophic nitrification and heterotrophic nitrification rates with the addition of swine manure (SW) and swine-manure-derived biochar (SWB) in two paddy soils. Materials and methods: SW and SWB were applied at four N-based amendment levels, namely control (0 mg N kg−1), low (1.1 mg N kg−1), medium (2.2 mg N kg−1), and high (4.4 mg N kg−1). Twenty-five milliliters of C2H2 gas were injected into each storage bottle to inhibit autotrophic nitrification in soil. At the end of the preincubation period, 160 mg kg−1 15N-glycine were added to each storage bottle to stimulate heterotrophic nitrification in soil. Results and discussion: Results showed that SW increased the NH4+-N content by 3.5 to 17.5 mg kg−1 in both soils, while SWB decreased it by 0.1 to 4.7 mg kg−1 compared to control group, regardless of whether autotrophic nitrification was inhibited. Both SW and SWB enhanced NO3−-N accumulation in the two soils compared to control group when autotrophic nitrification was not inhibited; however, NO3−-N concentration in the soil with SWB was up to 24% lower than that with the same level of SW addition. NH3 volatilization rates were elevated at all the SW and SWB amendment levels, although only SW led to higher N2O emission rates. Compared with SW, high level of SWB significantly decreased N2O emissions by 78 to 84% in the loam and clay loam soils. The increase in NH3 volatilization, soil NO3−-N accumulation, and autotrophic nitrification rate were greater with SW than with SWB. Higher rates of soil heterotrophic nitrification were observed in SWB-amended soils than in SW-amended soils with a high (4.4 mg N kg−1) amendment level. Conclusions: Our results suggest that SWB is less likely to increase NO3−-N accumulation in soil and contributes more to the lower soil autotrophic nitrification rate compared with SW. Although SWB can promote heterotrophic nitrification, it generally inhibits the autotrophic nitrification process and slows the increment pace of the gross nitrification in paddy soils. [ABSTRACT FROM AUTHOR]

Although research regarding antibiotic resistance genes (ARGs) in aquaculture environments has gained increasing scientific interest, further studies are required to understand the abundances and removal mechanisms of ARGs during the entire rearing period of shrimp aquaculture. Thus, in this study, abundances, distributions and removal rates of ARGs in different environmental compartments of intensive shrimp farms in South China were investigated during the entire rearing period. The results indicated that sul1 and cmlA were the predominant ARGs in the water and sediment samples. Additionally, the total abundance of ARGs was higher in shrimp pond water than in the source water and farm effluent. Moreover, sediment samples indicated significantly higher ARG abundances than water samples from the shrimp ponds (P < 0.05). Environmental factors were found to significantly affect the distribution of ARGs in shrimp rearing environments. Furthermore, stable ponds aided the removal of ARGs from shrimp pond water. This study accounted for temporal variations in ARG abundances as well as removal of ARGs in different environmental compartments during the entire shrimp rearing period. However, additional research is required to optimize the water treatment process for removal of ARGs from the aquaculture. [ABSTRACT FROM AUTHOR]

Purpose: The sources of and changes in molecular composition of soil organic carbon (SOC) due to land use change in a paddy soil chronosequence ˃6000 years old were studied using a lipid biomarker approach. Materials and methods: Lipid biomarkers comprising fatty acids, aliphatic alcohols, and sterols were used to evaluate rice field reclamation and management over 6000 years on sources of and changes in molecular composition of SOC in two soil profiles comprising of the following three soil chronosequence layers (from bottom to top): 6280-year-old BP prehistoric paddy soil/pristine upland, 3320-year-old BP ancient paddy soil, and the present paddy soil. Furthermore, comparison with adjacent abandoned paddy soils was made to indicate the effect of abandoning cultivation due to urbanization on the sources and fluctuations in the molecular composition of SOC. Results and discussion: Fatty acids and aliphatic alcohols represented the most abundant fraction (∼80%) of autochthonous organic carbon sources from microbial activity in the prehistoric pristine upland. Reclamation of pristine upland to submerged rice fields led to 44.5 and 41.1% increases in the ratio of long-chain n-fatty acids and n-alcohols (≥C22), respectively, to the total saturated homologs indicating an increased input of allochthonous organic matter sources derived from rice cropping. The evolution of the paddy soil from 6280 to 3320 years BP and then to the present was accompanied by a slight and gradual increase in the proportion of the higher plant-derived organic components. Abandonment of rice cropping led to an apparent decrease in the concentration of the lipid biomarkers suggesting a decline in rice roots and stubble inputs and of microbial activity. Conclusions: Lipid biomarkers can be used to trace the sources and fluctuations in the molecular composition of SOC in paddies owing to land use change. Fatty acids were more suitable as the lipid proxy than aliphatic alcohols or sterols. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD), the most prevalent form of dementia worldwide, is a complex neurodegenerative disease characterized by the progressive loss of memory and other cognitive functions. The pathogenesis of AD is not yet completely understood. Although long non-coding RNAs (lncRNAs) have recently been shown to play a role in AD pathogenesis, the specific influences of lncRNAs in AD remain largely unknown; in particular, hippocampal lncRNA expression profiles in AD rats are lacking. In this study, microarray analysis was performed to investigate the hippocampal expression patterns of dysregulated lncRNAs in a rat model of AD. A total of 315 lncRNAs and 311 mRNAs were found to be significantly dysregulated in the AD model (≥2.0 fold, p < 0.05). Then, quantitative real-time PCR was used to validate the expression of selected lncRNAs and mRNAs. Bioinformatics tools and databases were employed to explore the potential lncRNA functions. This is the first study to comprehensively identify dysregulated hippocampal lncRNAs in AD and to demonstrate the involvement of different lncRNA expression patterns in the hippocampal pathogenesis of AD. This information will enable further research on the pathogenesis of AD and facilitate the development of novel AD therapeutics targeting lncRNAs. [ABSTRACT FROM AUTHOR]

To assess the effect of addition of probiotics and carbon source on the microbial community structure within the shrimp culture, an enclosure system simulating a high density, intensive aquaculture of Litopenaeus vannamei was set up in Dianbai, Maoming, Guangdong province, China. The phylogenetic profiles of microbial communities in the enclosure system after addition of Bacillus and molasses were studied in the middle and final culture season (on the 45th, 75th and 95th day) using polymerase chain reaction-denaturing gradient gel electrophoresis. A total of four groups, each containing a triplicate were set up: Group A (control), Group B (64% of daily feed was provided as molasses with Bacillus sp.), Group C (50% of daily feed amount provided as molasses with Bacillus sp.) and Group D (64% of daily feed amount as molasses alone). The results showed that α- Proteobacteria, δ- Proteobacteria, Bacteroidetes and Actinobacteria were the dominant bacteria. Moreover, the relative proportion of α- Proteobacteria increased and that of Bacteroidetes decreased gradually with time. Pathogenic Flexibacter was the dominant genus in Group A on the 45th day, while the functional strains ( Sphingomonas sp., Erythrobacter sp. , Roseobacter sp., and Rhodobacter sp.) were detected multiple times in Groups B and C. Bacillus sp. was the cultivable, dominant bacterium in Groups B and C on the 95th day. Therefore, the combined use of Bacillus and molasses helped increase diversity of the microbial community, effectively inhibit pathogens, and promote the formation and development of a beneficial microbial community structure in the high density, intensive aquaculture of L. vannamei. [ABSTRACT FROM AUTHOR]

This study examined the phylogenetic and metabolic features of microbial communities in Baisha Bay mariculture areas of Nan'ao Island, a mariculture base on the Chinese Guangdong coast. Large seaweed ( Gracilaria lemaneiformis) cultivation zones (LZ), fish culture zones (FZ), and control zones (CZ) were sampled. According to community-level physiological profiling, d-mannitol, d-mannitol/α- d-lactose, and d-mannitol/α-cyclodextrin were the carbon sources with the highest utilization rates in CZ, LZ, and FZ, respectively ( R > 1.9). Denaturing gradient gel electrophoresis analysis showed that the dominant bacteria in CZ and LZ were Alphaproteobacteria (39.9 and 34.5%, respectively), whereas in FZ they were Flavobacteria (32.2%). The Shannon diversity in CZ and LZ was significantly higher than in FZ ( P < 0.05). Some opportunistic pathogens, such as Vibrio, Pseudoalteromonas and Loktanella, were abundant in FZ. The microbial communities and most of the dominant bacteria in FZ were more affected by environmental factors including salinity, chemical oxygen demand and total phosphorus. Some bacteria, such as Brevundimonas and Polaribater, have the potential to degrade agar in seaweed, and were isolated from samples rich in algae which are dominant in LZ. The cultivation of G. lemaneiformis created the notable structures and functions of macroalgae-associated bacterial communities that were less affected by the environmental factors examined. [ABSTRACT FROM AUTHOR]

Rice cultivation requires large quantities of irrigation water and mineral fertilizers. This provides an opportunity for the recycling of the plant nutrients in anaerobically digested pig slurry, large amounts of which are generated in Chinese pig farms. Hence, to promote the sustainable development of livestock and poultry breeding and rice production, a micro-plot field experiment was carried out to assess whether or not slurry can replace mineral fertilizers in rice paddy production in terms of plant tillering, grain quality, and yields. The results indicate that the total N content of the slurry can serve as an alternative source of N when compared to the control (450 kg ha commercial compound fertilizer (N/PO/KO = 15:15:15) as basal fertilizer, 300 kg ha urea (N% = 46), and 150 kg ha commercial compound fertilizer as top-dressed fertilizer). No negative effects on plant growth or grain yield were observed, although there may be a potential risk due to an increase in grain Cu concentration. The amylose content and gel consistency of the rice grains were enhanced significantly by the use of slurry as a basal fertilizer, but the grain protein and total amino acid contents decreased. The results suggest that anaerobically digested pig slurry can replace mineral fertilizers in rice production when applied as a basal dressing together with urea and commercial compound fertilizer as top-dressed fertilizers. [ABSTRACT FROM AUTHOR]

The influence from the manufacturing of compact fluorescent lamps (CFL) on mercury (Hg) speciation and distribution in river catchments nearby a typical CFL manufacturing area in China was investigated. Water, sediment, river snail ( Procambarus clarkii), and macrophyte ( Paspalum distichum L.) samples were collected. Total Hg (THg) and methylmercury (MeHg) concentrations in water ranged from 1.06 to 268 ng · L and N.D. −2.14 ng · L, respectively. MeHg was significantly positively correlated with THg in water. THg and MeHg in sediment ranged from 15.0 to 2480 and 0.06 to 1.85 ng · g, respectively. River snail samples exhibited high concentrations of THg (206-1437 ng · g) and MeHg (31.4-404 ng · g). THg and MeHg concentrations in root of P. distichum L. were significantly higher than those in shoot, indicating that THg and MeHg in the plant were mainly attributed to root assimilation. A very high bioaccumulation factor (20.9 ± 22.1) for MeHg in P. distichum L was noted, suggesting that P. distichum L. might have a potential role in phytoremediating MeHg contaminated soil due to its abnormal uptake capacity to MeHg. [ABSTRACT FROM AUTHOR]

Purpose: Submerged rice cultivation has been practiced in China for 7000 years. Empirical evidence on changes of soil organic carbon (SOC) contents in paddy soils over this historical time period is scarce. Therefore, a field study was conducted to investigate the effect of submerged rice cultivation on the accumulation and preservation of SOC in paddies. Materials and methods: Two buried ancient paddy profiles (6280 years BP, named P-01 and P-03) in the Yangtze Delta of eastern China were excavated to illustrate the development of SOC contents in soils during the evolution of paddies under anthropogenic land use and environmental changes from the prehistoric period to the present time. Trends in SOC concentrations, total nitrogen concentrations, and stable carbon isotope ratio were identified for different points in time. Results and discussion: Accumulation of organic carbon was found in the paddy soil layers of P-01 at 100-174 cm depth. This site was taken under submerged rice cultivation in about 6280 years BP. The average SOC concentration in the prehistoric paddy topsoil in 100-130 cm depth was 1.27 %, which is seven times higher than that in the adjacent uncultivated land at 103-130 cm depth of P-03. This implies that the paddy soil has experienced substantial CO sequestration under submerged management during that time. By about 3320 years BP, organic carbon contents were halved, potentially due to marine inundation by sea level rise. Up to the year 2003, the SOC contents in all horizons in the present time paddy soil have increased, especially in the surface layer, indicative of continuous rice cultivation. However, due to rapid urbanization and industrialization, the cultivation of paddies in eastern China has gradually been discontinued leading to the loss of SOC stocks of approximately 10 % in a 6-year interval (from 2003 to 2009). A significant relationship between SOC and rice phytolith contents was found in the paddy soil horizons of P-01 ( r = 0.71, p < 0.01) and P-03 ( r = 0.72, p < 0.01), suggesting that phytolith-occluded organic carbon could be used as a biomarker to ascertain the development of SOC in the evolution of rice paddies over the past 6000 years. Conclusions: Submerged rice cultivation led to a noticeable accumulation of SOC in paddies. Phytolith-occluded organic carbon could be used as a biomarker to monitor changes of OC contents in paddy soils. [ABSTRACT FROM AUTHOR]

The discussion about greenhouse gases emission mitigation focuses on the reduction of fossil fuels usage, which is extremely costly from the economic and social viewpoint. The analyses of CO2 and CH4 fluxes in the environment showed that intensifying natural photosynthesis and respiration process may significantly contribute to the mitigation of greenhouse gases emission. It has been proven that the intensity of photosynthesis in land ecosystems could compensate for the increase of CO2 emission from anthropological sources. [ABSTRACT FROM AUTHOR]

Copyright of Mineral Resources Management / Gospodarka Surowcami Mineralnymi is the property of Mineral & Energy Economy Research Institute of the Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Characteristics of a microbial community are important as they indicate the status of aquatic ecosystems. In the present study, the metabolic and phylogenetic profile of the bacterioplankton community in Guishan coastal water (Pearl River Estuary), South China Sea, at 12 sites (S1-S12) were explored by community-level physiological profiling (CLPP) with BIOLOG Eco-plate and denaturing gradient gel electrophoresis (DGGE). Our results showed that the core mariculture area (S6, S7 and S8) and the sites associating with human activity and sewage discharge (S11 and S12) had higher microbial metabolic capability and bacterial community diversity than others (S1-5, S9-10). Especially, the diversity index of S11 and S12 calculated from both CLPP and DGGE data ( H>3.2) was higher than that of others as sewage discharge may increase water nitrogen and phosphorus nutrient. The bacterial community structure of S6, S8, S11 and S12 was greatly influenced by total phosphorous, salinity and total nitrogen. Based on DGGE fingerprinting, proteobacteria, especially γ- and α-proteobacteria, were found dominant at all sites. In conclusion, the aquaculture area and wharf had high microbial metabolic capability. The structure and composition of bacterial community were closely related to the level of phosphorus, salinity and nitrogen. [ABSTRACT FROM AUTHOR]

Copyright of Ecological Chemistry & Engineering S / Chemia i Inzynieria Ekologiczna S is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Uncontrolled emissions of landfill gas may contribute significantly to climate change, since its composition represents a high fraction of methane, a greenhouse gas with 100- year global warming potential 25 times that of carbon dioxide. Landfill cover could create favourable conditions for methanotrophy (microbial methane oxidation), an activity of using bacteria to oxidize methane to carbon dioxide. This paper presents a brief review of methanotrophic activities in landfill cover. Emphasis is given to the effects of cover materials, environmental conditions and landfill vegetation on the methane oxidation potential, and to their underlying effect mechanisms. Methanotrophs communities and methane oxidation kinetics are also discussed. Results from the overview suggest that well-engineered landfill cover can substantially increase its potential for reducing emissions of methane produced in landfill to the atmosphere. [ABSTRACT FROM AUTHOR]

Sallow-skin horseshoe crabs (late juvenile Tachypleus tridentatus) from 30‰ salinity seawater were subjected to salinities ranging from 0‰ to 70‰ at 5‰ intervals for 7 days. They were returned to 30‰ salinity for 3 days for recovery. During this period, the survival rate, feeding rate, and body mass of the horseshoe crabs were measured. The sallow-skin horseshoe crabs survived well at 15‰–60‰ salinity, fed well at 30‰–55‰ salinity, gained mass at 0‰–25‰ salinity, lost mass at 45‰–70‰ salinity, and maintained mass at 30‰–40‰ salinity during salinity challenge. During the recovery period, the dehydrated (mass lost) horseshoe crabs rapidly gained mass, whereas the water-retaining (mass gained) horseshoe crabs rapidly lost mass. These results indicate that the sallow-skin T. tridentatus horseshoe crabs are osmoconformers and can tolerate a wide range of salinity changes, adapting gradually from inshore low salinity to offshore high salinity. [ABSTRACT FROM PUBLISHER]

The improper use of antibiotics has led to the development of bacterial resistance, resulting in fewer antibiotics for many bacterial infections. Especially, the drug resistance of hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) is distinctly serious. This research designed and synthesized two series of 3-substituted ocotillol derivatives in order to improve their anti-HA-MRSA potency and synergistic antibacterial activity. Among the synthesized compounds, 20–31 showed minimum inhibitory concentration (MIC) values of 1–64 µg/mL in vitro against HA-MRSA 18–19, 18–20, and S. aureus ATCC29213. Compound 21 showed the best antibacterial activity, with an MIC of 1 μg/mL and had synergistic inhibitory effects. The fractional inhibitory concentration index (FICI) value was 0.375, when combined with chloramphenicol (CHL) or kanamycin (KAN). The structure–activity relationships (SARs) of ocotillol-type derivatives were also summarized. Compound 21 has the potential to be developed as a novel antibacterial agent or potentiator against HA-MRSA. [ABSTRACT FROM AUTHOR]

Ginseng is one of the most widely consumed herbs in the world and plays an important role in counteracting fatigue and alleviating stress. The main active substances of ginseng are its ginsenosides. Ocotillol-type triterpenoid is a remarkably effective ginsenoside from Vietnamese ginseng that has received attention because of its potential antibacterial, anticancer and anti-inflammatory properties, among others. The semisynthesis, modification and biological activities of ocotillol-type compounds have been extensively studied in recent years. The aim of this review is to summarize semisynthesis, modification and pharmacological activities of ocotillol-type compounds. The structure–activity relationship studies of these compounds were reported. This summary should prove useful information for drug exploration of ocotillol-type derivatives. [ABSTRACT FROM AUTHOR]

Ammonia is the main pollution factor of the aquatic environment in marine shrimp culture systems. In order to demonstrate the feasibility of the combination of biofloc technology and nitrifying biofilter for the ammonia removal, a 70-day production trial was conducted in a simplified pilot-scale hybrid biofloc-based recirculating aquaculture system (biofloc-RAS) with the intensive culture of Litopenaeus vannamei. Nitrogen dynamics and nitrifying microbial communities were investigated in three replicated systems simultaneously under the conditions of high feed loading and zero water exchange. Along with biofloc development in the culture tank and biofilm formation in the nitrifying biofilter during the trial, nitrification could be fastly and effectively established in the system, which was indicated by the dynamics of total ammonia nitrogen (TAN), NO2–-N, NO3–-N, and total nitrogen (TN) concentrations. Meanwhile, similar nitrifying microorganisms could be found between biofloc and biofilm, despite some differences in abundance, diversity, and composition of ammonia-oxidizing archaea and bacteria and nitrite-oxidizing bacteria. High TAN removal rate could be achieved and was significantly and positively correlated with abundances of these nitrifying microbial communities in both biofloc and biofilm, further indicating that both biofloc and biofilm could contribute highly to nitrification performance of the biofloc-RAS. The results of this study indicate a potential application of the biofloc-RAS in coastal intensive aquaculture. [ABSTRACT FROM AUTHOR]