Degradation of pretilachlor and fenclorim and effects of these compounds on bacterial communities under anaerobic condition.

Pretilachlor and safener fenclorim are the main components of herbicides widely applied to control weeds. Although some pure cultures of bacteria and fungi which degraded these compounds under aerobic conditions were isolated, no isolated pretilachlor- and fenclorim-degrading bacterial strains under anaerobic condition had been available. In this study, the degradation of these compounds and the effects of them on bacterial community structures were investigated under anaerobic conditions. The dissipation rates of pretilachlor and fenclorim in slurries were in the order: soil from paddy field ≈ sediment from river > sediment from mangrove. Moreover, three pretilachlor-degrading bacterial strains (Pseudomonas sp. Pr1, Proteiniclasticum sp. Pr2 and Paracoccus denitrificans Pr3) and two fenclorim-degrading strains (Dechloromonas sp. Fe1 and Ralstonia pickettii Fe2) isolated from a slurry of paddy soil utilized the substrates as sole carbon and energy sources under anaerobic conditions. The degradation of pure pretilachlor and fenclorim at various concentrations by corresponding mixed pure cultures followed the Michaelis-Menten model, with the maximum degradation was 3.10 ± 0.31 µM/day for pretilachlor, and 2.08 ± 0.18 µM/day for fenclorim. During the degradation, 2-chloro-N-(2,6-diethylphenyl) acetamide and 2,6-dimethylaniline were produced in pretilachlor degradation, and benzene was a product of fenclorim degradation. The synergistic degradation of both substrates by all isolated bacteria reduced the metabolites concentrations accumulated in media. This study provides valuable information on effects of pretilachlor and fenclorim on bacterial communities in soil and sediments, and degradation of these substrates by isolated bacteria under anaerobic condition.

Competition between Loss of H2 versus H+H in the Fragmentation of the Fluorene Cation.

The fluorene cation is a frequently studied molecule in the context of fragmentation experiments. This is because of its potential role in interstellar chemistry, notably as a precursor of PAH cages. In this paper, we analyze H, H+ , H2 and H 2 + ${{\rm{H}}_2^ + }$ losses from the fluorene cation using the SMF (Statistical Molecular Fragmentation) model. We calculate the probabilities of all the 534 possible fragmentation channels as a function of the excitation energy, up to the loss of three hydrogens. Four different types of hydrogen atom pairings (from the same carbon, from the same ring, from different rings and across-the-bay) have been tested in order to determine which types contribute to the actual production of hydrogen molecules. The simulated breakdown curves are in very good agreement with different experimental results when same ring pairing is taken into account. It was possible to deduce from the model the locations of the emitted H, H+ , H2 and H 2 + ${{\rm{H}}_2^ + }$ species.

Use of Gaussian-Type Functions for Describing Fast Ion-Matter Irradiation with Time-Dependent Density Functional Theory.

The electronic stopping power is an observable property that quantifies the ability of swift ions to penetrate matter to transfer energy to the electron cloud. The recent literature has proven the value of Real-Time Time-Dependent Density Functional Theory to accurately evaluate this property from first-principles, but questions remain regarding the capability of computer codes relying on atom-centered basis functions to capture the physics at play. In this Perspective, we draw attention to the fact that irradiation by swift ions triggers electron emission into the continuum, especially at the Bragg peak. We investigate the ability of Gaussian atomic orbitals (AOC), which were fitted to mimic continuum wave functions, to improve electronic stopping power predictions. AOC are added to standard correlation-consistent basis sets or STO minimal basis sets. Our benchmarks for water irradiation by fast protons clearly advocate for the use of AOC, especially near the Bragg peak. We show that AOC only need to be placed on the molecules struck by the ion. The number of AOC that are added to the usual basis set is relatively small compared to the total number of atomic orbitals, making the use of such a basis set an excellent choice from a computational cost point of view. The optimum basis set combination is applied for the calculation of the stopping power of a proton in water with encouraging agreement with experimental data.

Bi-decadal trend of atmospheric emissions from thermal power plants in Mainland Southeast Asia: Implications on acid deposition and climate change Mitigation.

Steady increase in electricity generation and heavy reliance on coal in Mainland Southeast Asia (M-SEA) create huge pressure on the environment. This study used information collected from individual thermal power plants (TPPs) in M-SEA to calculate emissions of air pollutants and greenhouse gases (GHG) for 2010, 2015 and 2019. The emissions were projected to 2030 following the latest national Power Development Plans. The emission results were analyzed in relation to the power development by country and fuel type, and environmental impacts. The region collective annual TPP emissions in 2019, in Gg/yr, were 27 PM2.5, 77 PM10, 0.7 BC, 4.9 OC, 255 SO2, 451 NOx, 91 CO, 12 NMVOC, 0.4 NH3, 260 CO2, 13 CH4, and 26 N2O. Coal-fired TPPs dominated the emissions of most species while NG-fired contributed the largest amounts of NH3 and CH4. Bi-decadal increase in energy production from TPPs of nearly 3 times is accompanied by 2.7 times increase in emissions. The 2010-2019 period saw average emissions increase by 1.9 times (TPPs' energy production increased 1.6 times), slightly higher than the rate of 1.4 times projected for 2019-2030 (double TPPs' energy production). The current intrusion rate of renewable energy accompanied by phasing-out of old TPPs are still by far insufficient to reverse the emission trend. Aggressive power development in Vietnam with its heavy coal reliance made it the largest emitter in 2019 and the projected for 2030, followed by Thailand. Spatially, higher emissions are seen over locations of large coal-fired TPPs in Vietnam and Thailand. Available rainwater composition monitoring data showed higher deposition amounts of sulfate and nitrate in areas located near or downwind of large TPPs. Significant GHG emissions projected for TPPs in 2030 indicated that TPPs should be the priority for emission reduction to achieve Nationally Determined Contribution targets. Emission database produced by this study can be used in dispersion modeling studies to assess impacts of TPPs on air quality, health, and acid deposition.

Thiobencarb Degradation by Pseudomonas sp. Th1 and Cupriavidus oxalaticus Th2 Isolated from Soil.

Thiobencarb has been extensively applied for weed control, resulting in severe environmental problems. In this study, thiobencarb degradation in liquid media and in soil by two bacterial strains, Pseudomonas sp. Th1 and Cupriavidus oxalaticus Th2, was investigated. Both bacterial isolates utilized the compound as a sole carbon, nitrogen and sulfur source. The utilization rates of thiobencarb by Pseudomonas sp. Th1 and C. oxalaticus Th2 in a liquid mineral medium were 1.02 ± 0.11 and 0.80 ± 0.07 µM/h at 100 µM, respectively. The determination of degradation and bacterial growth rates kinetics showed that the rates for pure thiobencarb followed the Michaelis-Menten model; meanwhile, the rates for thiobencarb in a commercial herbicide fitted well with the Edwards model. Their degradation by the mixed culture of both strains reduced the accumulation of intermediate products, including S-4-chlorobenzyl ethylthiocarbamate and 4-chlorobenzyl mercaptan, in media. The degradation by the mixed culture of these bacteria immobilized in rice straw was significantly higher than those of their free counterparts when determining in a packed bed bioreactor (P < 0.05). In addition, the inoculation of the mixed bacterial culture in soil significantly enhanced the degradation performance for both thiobencarb and propanil in a commercial herbicide. This study elucidates the differences in biodegradation of pure thiobencarb and thiobencarb in an herbicide.

Current Situation and Causes Analysis of Cadmium Pollution in the Kakehashi River Basin.

Cadmium (Cd) pollution is a public environmental problem worthy of attention. Long-term exposure to Cd may have adverse effects on human health. Our previous study showed that urinary concentration of Cd (U-Cd) in the residents decreased when Cd-polluted paddy soil was removed. However, from 2008 to 2014, the concentration of U-Cd increased. At the same time, the concentration of urinary ß2-microglobulin (ß2-MG), which is considered to be an early sign of cadmium-induced renal dysfunction, increased continuously. To find the cause of elevated urinary cadmium (U-Cd) in residents of cadmium-contaminated areas, we measured the concentration of cadmium in the blood (B-Cd) of 29 elderly residents (15 female and 14 male) and edible rice (R-Cd), and correlations between R-Cd, B-Cd, and U-Cd were analyzed in the formerly cadmium-polluted areas (the Kakehashi River basin). In 2016, we collected blood, urine, and rice samples from each participant. The analysis showed a significant correlation between age and B-Cd, U-Cd, and ß2-MG. However, there was no significant correlation between R-Cd and U-Cd, B-Cd, or ß2-MG concentrations. Although we found a slightly higher level of Cd in rice and urine than reported in 2008, we cannot be sure that it indicates an increased Cd contamination in the Kakehashi River basin because larger studies are required for such a conclusion. The increased urinary Cd concentrations in this area may be because Cd in tissues and organs returns to blood and urine as participants age, which leads to an increasing trend.

Three new species of the genus Spinadesha Quicke (Hymenoptera: Braconidae: Braconinae) from Vietnam.

This paper contains descriptions and illustrations of three new species of the genus Spinadesha Quicke from Vietnam, viz. Spinadesha alia Long, sp. nov., S. crista Long, sp. nov. and S. intermedia Long, sp. nov. The genus Spinadesha is recorded for the first time from Vietnam, and a key to the species of Spinadesha is provided.

A 30-year follow-up study in a former cadmium-polluted area of Japan: the relationship between cadmium exposure and ß2-microglobulin in the urine of Japanese people.

Cadmium (Cd) is an environmental pollutant. Long-term exposure to Cd may lead to adverse health effects in humans. Our epidemiological studies showed that urinary Cd (U-Cd) concentrations increased from 2008 through 2014, although they decreased from 1986 through 2008. The aim of this study was to elucidate the long-term effects of the changing trend of cadmium exposure levels (U-Cd) on residents' renal function within 30 years after Cd exposure ceased. In 2016, urine samples were collected from each subject by visiting 20 elderly Japanese people (9 females and 11 males) living in the Kakehashi River basin, a previously Cd-polluted area in Ishikawa, Japan. The geometric means of the ß2-microglobulin (ß2-MG) and urinary Cd (U-Cd) continued to increase from 2014 until 2016. Furthermore, Cd concentration and ß2-MG in urine were still higher than those in the non-polluted areas in Japan. Multivariate linear regression was performed to associate ß2-MG (dependent variable) and U-Cd with sex and age (independent variables). Significant correlations were found among age, U-Cd, and ß2-MG, and these were clearer in females than in males. In summary, we propose that three decades after Cd exposure ceased, age is associated with ß2-MG more strongly than Cd for bodily impact. Moreover, renal tubular dysfunction is irreversible and worsens after exposure to Cd, with females being more sensitive to exposure.

Review of the genus Arhaconortus Belokobylskij, 2000 (Hymenoptera: Braconidae: Doryctinae), with description of three new species from Vietnam.

In the present study, the genus Arhaconotus is revised and keyed with three species of this genus from Vietnam were described and fully illustrated as new for science, viz.Arhaconotus belokobylskiji Long,sp. nov., A. hoabinhicus Long,sp. nov. and A. longicaudatus Long,sp. nov., and one species, A. hainanensis Tang & Chen, 2010 newly recorded for Vietnams braconid fauna. Up to know, a total of seven species of Arhaconotus are described, a key to all the already known Arhaconotus species is provided. Comparative morphological characters of Arhaconotus species were also discussed.

The identity of Chivinia Shestakov (Hymenoptera: Braconidae, Braconinae), with description of a similar species from the Oriental region.

A peculiar new species from Vietnam (Bracon (Pseudochivinia) tobiasi Long & van Achterberg, sp. nov.) is described and illustrated. It is included in a new subgenus Pseudochivinia Long & van Achterberg, subgen. nov., because it does not fit into the superficially similar subgenus Chivinia Shestakov. The new subgenus shares with Chivinia Shestakov the absence of vein r-m of the fore wing (resulting in the absence of a closed second submarginal cell) but can be distinguished from Chivinia and other subgenera of the genus Bracon Fabricius by the deep and crenulate medio-longitudinal depression of the first metasomal tergite and the different venation. Bracon (Chivinia) zimini Shestakov, 1932 is redescribed and illustrated for the first time.

In-depth theoretical understanding of the chemical interaction of aromatic compounds with a gold nanoparticle.

Gold Nanoparticles (GNPs), owing to their unique properties and versatile preparation strategy, have been demonstrated to exhibit promising applications in diverse fields, which include bio-sensors, catalysts, nanomedicines and radiotherapy. Yet, the nature of the interfacial interaction of GNPs with their chemical environment remains elusive. Experimental vibrational spectroscopy can reveal different interactions of aromatic biological molecules absorbed on GNPs, that may result from changes in the orientation of the molecule. However, the presence of multiple functional groups and the aqueous solvent introduces competition, and complexifies the spectral interpretations. Therefore, our objective is to theoretically investigate the adsorption of aromatic molecules containing various functional groups on the surface of GNPs to comparatively study their preferred adsorption modes. The interaction between Au32, as a model of GNPs, and a series of substituted aromatic compounds that includes benzene, aniline, phenol, toluene, benzoic acid, acetophenone, methyl benzoate, and thiophenol, is investigated. Our computed interaction energies highlight the preference of the aromatic ring to lie flat on the surface. The orientations of the molecules can be distinguished using infrared spectroscopy along with strong changes in intensity and significant shifts of some vibrational modes when the molecule interacts with the GNP. The interaction energy and the electron transfer between the nanoparticle and the aromatic molecule are not found to correlate, possibly because of significant back donation of electrons from GNPs to organic molecules as revealed by charge decomposition analysis. A thorough quantum topological analysis identifies multiple non-covalent interactions and assigns the nature of the interaction mostly to dative interactions between the aromatic ring and the GNP as well as dispersive interaction. Finally, energy decomposition analyses point out the role of the charge transfer energy contribution in the subtle balance of the different physical components.

Regulation of nuclear DNA damage response by mitochondrial morphofunctional pathway.

Cells are constantly challenged by genotoxic stresses that can lead to genome instability. The integrity of the nuclear genome is preserved by the DNA damage response (DDR) and repair. Additionally, these stresses can induce mitochondria to transiently hyperfuse; however, it remains unclear whether canonical DDR is linked to these mitochondrial morphological changes. Here, we report that the abolition of mitochondrial fusion causes a substantial defect in the ATM-mediated DDR signaling. This deficiency is overcome by the restoration of mitochondria fusion. In cells with fragmented mitochondria, genotoxic stress-induced activation of JNK and its translocation to DNA lesion are lost. Importantly, the mitochondrial fusion machinery of MFN1/MFN2 associates with Sab (SH3BP5) and JNK, and these interactions are indispensable for the Sab-mediated activation of JNK and the ATM-mediated DDR signaling. Accordingly, the formation of BRCA1 and 53BP1 foci, as well as homology and end-joining repair are impaired in cells with fragmented mitochondria. Together, these data show that mitochondrial fusion-dependent JNK signaling is essential for the DDR, providing vital insight into the integration of nuclear and cytoplasmic stress signals.

Composition of bacterial community and isolation of bacteria responsible for diuron degradation in sediment and soil under anaerobic condition.

The herbicide diuron is extensively used in the agriculture sector and is detected widely in the environment. Although several studies on the degradation of diuron by aerobic microorganisms have been reported, the degradation of diuron by anaerobic microorganisms has not been received much attention. Also, no pure culture that can degrade diuron under anaerobic conditions has yet been reported. The evaluation of diuron degradation in the soil and sediment slurries showed that diuron led to a decrease in the biodiversity of the bacterial communities. Two mixed bacterial cultures, one from the soil and the other from sediment slurries, were isolated from the enrichment media under anaerobic conditions. After 30 days of incubation at 30 °C, the mixed bacterial culture from the soil degraded 84.5 ± 5.5%, and that from the sediment slurry degraded 94.5 ± 3.0% of diuron in liquid mineral medium at an initial concentration of 20 mg/L. 1-(3,4-dichlorophenylurea (DCPU), 3-(3-chlorophenyl)-1,1-dimethylurea (CPDMU), and 3,4-dichloroaniline (3,4-DCA) were the major diuron metabolites produced by both the indigenous microorganisms and the isolated bacteria.

Four new species of the subfamily Braconinae (Hymenoptera: Braconidae) from Vietnam.

This paper contains descriptions and illustrations of four new species of braconine wasps from two genera Megalommum Szpligeti, 1900 and Nedinoschiza Cameron, 1911 from Vietnam, viz. Megalommum hoabinhense Long, sp. nov., M. simulatum Long, sp. nov., M. sonlaense Long, sp. nov. and Nedinoschiza khuathalinhae Long, sp. nov. Additionally, the genus Megalommum is the first record for Vietnam.

Research Priorities of Applying Low-Cost PM2.5 Sensors in Southeast Asian Countries.

The low-cost and easy-to-use nature of rapidly developed PM2.5 sensors provide an opportunity to bring breakthroughs in PM2.5 research to resource-limited countries in Southeast Asia (SEA). This review provides an evaluation of the currently available literature and identifies research priorities in applying low-cost sensors (LCS) in PM2.5 environmental and health research in SEA. The research priority is an outcome of a series of participatory workshops under the umbrella of the International Global Atmospheric Chemistry Project-Monsoon Asia and Oceania Networking Group (IGAC-MANGO). A literature review and research prioritization are conducted with a transdisciplinary perspective of providing useful scientific evidence in assisting authorities in formulating targeted strategies to reduce severe PM2.5 pollution and health risks in this region. The PM2.5 research gaps that could be filled by LCS application are identified in five categories: source evaluation, especially for the distinctive sources in the SEA countries; hot spot investigation; peak exposure assessment; exposure-health evaluation on acute health impacts; and short-term standards. The affordability of LCS, methodology transferability, international collaboration, and stakeholder engagement are keys to success in such transdisciplinary PM2.5 research. Unique contributions to the international science community and challenges with LCS application in PM2.5 research in SEA are also discussed.

Enhanced anaerobic degradation of thiobencarb using a horizontal-flow anaerobic immobilized biomass bioreactor.

Thiobencarb is a herbicide globally used in the agricultural sector, and its extensive application leads to severe environmental pollution. In this study, the thiobencarb supplementation caused a significant shift in the bacterial community in the sediment slurry. An analysis of the degradation metabolites of microorganisms from the sediment indicated that deschlorothiobencarb, S-4-chlorobenzyl ethylthiocarbamate, 4-chlorobenzyl mercaptan, 4-chlorobenzyl alcohol, 4-chlorobenzoic acid and chlorobenzene were the main intermediates. The degradation rates were significantly enhanced using a horizontal-flow anaerobic reactor with immobilized cells in polyurethane foam. The degradation rates at 2.6, 12.9 and 25.6 mg L-1 concentrations by suspended microorganisms from the sediment in the mineral medium supplemented with glucose were 0.085 ± 0.000, 0.383 ± 0.010 and 0.500 ± 0.045 mg day-1, respectively. The corresponding data for degradation in the reactor were 2.54 ± 0.03, 11.69 ± 0.72 and 18.58 ± 1.83 mg day-1 at the sixth operation period. Moreover, COD removal efficiencies were >90% achieved in the reactor. The proposed method facilitates degradation using a horizontal-flow anaerobic immobilized biomass bioreactor. Moreover, this study reveals the degradation of metabolites of thiobencarb under anaerobic conditions.

Large spatio-temporal variations of size-resolved particulate matter and volatile organic compounds in urban area with heavy traffic.

A monitoring campaign, the first of this kind for a heavy traffic urban area of Vietnam, was conducted which generated nearly 200 daily filter samples of PM2.5, PM10, and black carbon (BC), 1300 online hourly PMx (PM10, PM2.5, and PM1), 900 hourly/bi-hourly BTEX data, 700 h of traffic counts, and online meteorology records. PMx and BTEX levels show large horizontal gradients across this small urban area of 300 m width suggesting that the pollution data should be generated with sufficient spatial resolutions for assessment of the exposure and health effects. This paper focuses on analyzing PMx with reference to the previously published BTEX to provide a more complete picture of the traffic-related pollution in the area. Spatio-temporal variations of pollutants are analyzed in relation to traffic flows and fleet compositions, weekday-weekend effects, local and regional meteorology. PM10 and BTEX levels had larger variations between the sites indicating their stronger associations with the traffic activities than the finer particles. Twenty-four-hour (24 h) PM2.5 levels ranged between 19 and 191 µg/m3 with high PM1/PM2.5 ratios of above 0.8 at ambient site (AA) and above 0.7 at roadsides. Multivariate relationship analysis (PCA) for the bi-hourly datasets of meteorology, traffic flows, and pollutant levels indicated overwhelming influence of on-road traffic fleet compositions on the roadside pollutants levels. At AA, PCA results showed a complex interaction between local emissions, meteorological conditions, and regional/long-range transport. Higher pollution levels were associated with the airmass types having the continental origin and pathways.

Degradation of Diuron by a Bacterial Mixture and Shifts in the Bacterial Community During Bioremediation of Contaminated Soil.

Diuron, a phenylurea herbicide, has been extensively applied in controlling a wide range of weeds in several crops. In the current study, a mixed culture of three bacterial strains, i.e., Bacillus subtilis DU1, Acinetobacter baumannii DU, and Pseudomonas sp. DUK, isolated from sugarcane soil, completely degraded diuron and 3,4-DCA in liquid media at 20 mg L-1 within 48 h. During diuron degradation, a few metabolites (DCPMU, DCPU, and 3,4-DCA) were produced. Further determination of ring-cleavage pathways demonstrated that Acinetobacter baumannii DU and Pseudomonas fluorescens DUK degraded diuron and 3,4-DCA via ortho-cleavage. In contrast, Bacillus subtilis DU transformed these compounds via meta-cleavage pathways. Moreover, diuron caused a significant shift in the bacterial community in soil without diuron history. The augmentation of mountain soil with the isolated bacteria resulted in nearly three times higher degradation rate of diuron than the degradation by indigenous microorganisms. This study provides important information on in situ diuron bioremediation from contaminated sites by bioaugmentation with a mixed bacterial culture.

Six new braconid wasps of the genus Colastomion Baker, 1917 (Hymenoptera: Braconidae: Rogadinae) from Vietnam.

The relatively small genus Colastomion Baker, 1917 is newly recorded for Vietnams braconid fauna and six new species are described and fully illustrated, viz. Colastomion asperum Long, sp. n; Colastomion cephonodes Long PVLam, sp. n.; Colastomion citrum Long, sp. n.; Colastomion neuterum Long, sp. n.; Colastomion nigroconfusum Long Pham, sp. n. and Colastomion vietnamenese Long, sp. n. Based on both females and males, a key to the new species from Vietnam is given. Diagnostic characters of the new species are also analyzed and compared with other Colastomion species from the Oriental region. Additionally, the first host record for the new species, C. cephonodes sp. n., is provided as this new species is reared from caterpillars of the coffee hawkmoth, Cephonodes hylas (Linnaeus, 1771).

Assessing feasibility of establishing antimicrobial stewardship programmes in two provincial-level hospitals in Vietnam: an implementation research study.

OBJECTIVES: To investigate the feasibility of establishing hospital-based antimicrobial stewardship (AMS) programmes comprising action-planning, educational interventions and data feedback in two provincial-level hospitals in Viet Nam. DESIGN AND SETTING: This was an implementation research using participatory action process and existing resources from the Duke Antimicrobial Stewardship Outreach Network with local adjustments. A national stakeholder meeting and Strengths-Weaknesses-Opportunities-Threats (SWOT) analysis were conducted to identify gaps and potential interventions. PARTICIPANTS: Hospital AMS staff implemented activities throughout the study phases. Routinely collected patient data were analysed to support planning, implementation and evaluation. INTERVENTIONS: Hospitals were considered as a complex adaptive system and leveraged their unique characteristics and interconnections to develop 1-year plans containing core interventions (data use, educational training, prospective audit with feedback (PAF) and evaluations). OUTCOME MEASURES: We assessed feasibility using outputs from stakeholder meeting, SWOT analysis, baseline data, planning process and implementation. RESULTS: The stakeholder meeting identified three gaps for AMS at national level: supportive policies, AMS training and core competencies and collaboration. At the hospitals, AMS programmes took 1 year for planning due to lack of hospital-specific procedures and relevant staff competencies. Baseline data (January-December 2019) showed variations in antibiotic consumption: 951 days of therapy (DOT) per 1000 days present in the control and 496 in the intervention wards in hospital 1, and 737 and 714 in hospital 2, respectively. During 1-year implementation, clinical pharmacists audited 1890 antibiotic prescriptions in hospital 1 (June 2020-May 2021) and 1628 in hospital 2 (July 2020-July 2021), and will continue PAF in their daily work. CONCLUSION: Our data confirmed the need to contextualise AMS programmes in low-income and middle-income countries (LMICs) and demonstrated the usefulness of implementation research design in assessing programme feasibility. Developing staff competencies, using local data to stimulate actions and integrating programme activities in routine hospital work are key to success in LMICs.