Influence of lignin, pentachlorophenol and heavy metal on antibiotic resistance of pathogenic bacteria isolated from pulp paper mill effluent contaminated river water

Pulp paper mill pollutants are the major source of aquatic contamination having metals, lignin and chlorophenols. Study was conducted to see the effect of these contaminants on antibiotic resistance pattern of isolated bacteria. Pulp paper effluents were evaluated for its physico-chemical properties i.e, BOD 72143 +/- 164.81 to 22.32 +/- 2.48, COD 213136 +/- 583.59 to 60.40 +/- 6.34, total phenol 386 +/- 71.24 to 0.43 +/- 0.0, lignin 26312 +/- 258.59 to 73.67 +/- 31.81and microbial quality i.e. K. pneumonae, S. typhi, S. faecalis, P. aeruginosa, E. coli, Ent. faecalis, A. hydrophila, B. subtilis, S. aureus, Y enterolitica and V vulrificus. Antibiotic sensitivity (10-30 microg), heavy metal resistance (100-1000 microg ml(-1)), lignin (1000-10,000 ppm) and pentachlorophenol (100-1000 ppm) tolerance of bacterial strains were assessed by seven classes of antibiotics. Eleven bacterial isolates were found multidrug resistant towards antibiotics, heavy metal, lignin and PCP. Out of 11 isolates, 90.9% were found resistant against eleven antibiotics which acquired 100% resistant in presence of heavy metal, lignin and chlorophenols. Results also revealed that concentration of lignin (50-350 ppm) and PCP (5-30 ppm) induced maximum growth (273-8050 cfu ml(-1)) of pathogenic bacteria in river water.     

Trade transport and environment linkages at the U.S.–Mexico border: Which policies matter?

We apply a fixed-effects model to examine the impact of trade and environmental policies on air quality at ports along the U.S.-Mexico border. We control for other factors influencing air quality, such as air quality of cities near the border, volume of traffic flows and congestion. Results show the air quality improved after 2004, when the diesel engine policy was applied. We see mixed results for the trade policy, whose implementation time varies across ports along the international border. Controlling for air quality in cities near the border is essential for assessing the policy contributions to air quality.     

Eutectic mixture promoted CO2 sorption on MgO-TiO2 composite at elevated temperature

The development of carbon dioxide(CO_2) sorbents that can operate at elevated temperatures is significant for the advancement of pre-combustion capture technologies.Recently, promoter-based systems composed of alkali/alkaline earth metal nitrates and/or carbonates have been considered as next-generation solid sorbents due to their improved CO_2 uptake and kinetics. However, obtaining stable MgO sorbents against temperature swing regeneration still remained challenging. Herein, we report MgO-TiO_2 solid sorbents promoted by eutectic mixture(KNO_3 and LiNO_3) for elevated temperature CO_2 sorption. The developed sorbents show improved CO_2 sorption capacity, which may be attributed to the alternative CO_2 sorption pathway provided by the ionization of highly dispersed MgO in the eutectic mixture. The MgO-TiO_2 framework was also shown to assist in retaining the MgO configuration by constraining its interaction with CO_2. Furthermore, it is demonstrated that constructing composite structures is essential to improve the CO_2 sorption characteristics,mainly recyclability, at elevated temperatures. The developed promoter integrated sorbents showed exceptionally high CO_2 sorption capacity of 30 wt.% at an elevated temperature(300°C) with pronounced stability under temperature swing operation.     

Autoantibodies and autoimmune disorders in SARS-CoV-2 infection: pathogenicity and immune regulation

Environmental Science and Pollution Research - Coronavirus disease 2019 (COVID-19) is an infectious disease associated with the respiratory system caused by the SARS-CoV-2 virus. The aim of this...     

UMW: Umweltmonitoring Dr. Monica W?ber

Ohne Zusammenfassung     

Incorporating fragmentation and non‐native species into distribution models to inform fluvial fish conservation

Fluvial fishes face increased imperilment from anthropogenic activities, but the specific factors contributing most to range declines are often poorly understood. For example, the range of the fluvial‐specialist shoal bass (Micropterus cataractae) continues to decrease, yet how perceived threats have contributed to range loss is largely unknown. We used species distribution models to determine which factors contributed most to shoal bass range loss. We estimated a potential distribution based on natural abiotic factors and a series of currently occupied distributions that incorporated variables characterizing land cover, non‐native species, and river fragmentation intensity (no fragmentation, dams only, and dams and large impoundments). We allowed interspecific relationships between non‐native congeners and shoal bass to vary across fragmentation intensities. Results from the potential distribution model estimated shoal bass presence throughout much of their native basin, whereas models of currently occupied distribution showed that range loss increased as fragmentation intensified. Response curves from models of currently occupied distribution indicated a potential interaction between fragmentation intensity and the relationship between shoal bass and non‐native congeners, wherein non‐natives may be favored at the highest fragmentation intensity. Response curves also suggested that >100 km of interconnected, free‐flowing stream fragments were necessary to support shoal bass presence. Model evaluation, including an independent validation, suggested that models had favorable predictive and discriminative abilities. Similar approaches that use readily available, diverse, geospatial data sets may deliver insights into the biology and conservation needs of other fluvial species facing similar threats.     

不同热解温度生物炭对 Cd(Ⅱ)的吸附特性

以花生壳和中药渣为原料,分别于300、350、400、500、600℃下慢速热解制备生物炭,并表征其物理化学性质.研究不同p H、吸附时间和Cd(Ⅱ)浓度下生物炭对Cd(Ⅱ)的吸附特征.结果表明,随着热解温度的升高,生物炭的碳化程度增加,比表面积增大,含氧官能团数量减少,π共轭芳香结构更加完备,Ca和Mg等无机元素不断富集,矿物溶解性降低,导致了Cd(Ⅱ)在不同热解温度生物炭上吸附能力及机制的差异.随溶液p H的升高(2.0~6.0),生物炭对Cd(Ⅱ)的吸附量逐渐增加.吸附过程可分为快吸附和慢吸附两个阶段,吸附速度受膜扩散、颗粒内扩散和沉淀作用、离子交换等过程的控制.随热解温度的升高,快吸附在生物炭对Cd(Ⅱ)的吸附中所占比例逐渐降低.高温生物炭(≥500℃)中含氧官能团的锐减及难溶晶体矿物的形成降低了其对Cd(Ⅱ)的快吸附速率.沉淀和离子交换可能是低温生物炭(≤400℃)吸附Cd(Ⅱ)的主要机制;高温生物炭(≥500℃)中更完备的π共轭芳香结构增加了Cd-π作用对吸附的贡献,而难溶磷酸盐和碳酸盐的形成则降低了沉淀作用对吸附的贡献.这些研究结果为筛选对Cd(Ⅱ)具有高效去除或固持能力的功能生物炭(designer biochar)提供了重要的理论数据.     

A Geospatial Methodology to Identify Locations of Concentrated Runoff from Agricultural Fields

A geospatial methodology has been developed that utilizes high resolution lidar‐derived DEMs to help track runoff from agricultural fields and identify areas of potential concentrated flow through vegetated riparian areas in the Coastal Plain of Virginia. Points of concentrated flow are identified across 74 agricultural fields within the Virginia portion of the Chesapeake Bay watershed. On average, 70% of the surface area of the agricultural fields analyzed drains through less than 20 m of the field margin, and on average 81% of the field surface area drains through 1% or less of the field margin. Within the riparian buffer, locations that were predicted by the geospatial model to have high levels of concentrated flow were found to exhibit evidence of channelization. Results indicate that flow concentration and channelized flow through vegetated riparian areas may be common along the margin of agricultural fields, resulting in vegetated riparian areas that are less effective at sediment trapping than assumed. Additional results suggest that the regulations governing the location and width of vegetated riparian may not be sufficient to achieve goals for reducing sediment and nutrient runoff from nonpoint agricultural sources. Combined with the increasing availability of lidar‐derived DEMs, the geospatial model presented has the potential to advance management practices aimed at reducing nonpoint source pollution leaving agricultural fields.