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https://www.readbyqxmd.com/read/29031188/azithromycin-sorption-and-biodegradation-in-a-simulated-california-river-system
#1
Monica L Vermillion Maier, Ronald S Tjeerdema
Azithromycin (AZ) is a widely-used macrolide antibiotic that is continually deposited into natural waterways by sewage effluent. Though recognized as an emerging contaminant of concern, little is known about its fate and transport in aquatic systems. American River soils and water were used to determine degradation of AZ in microcosms simulating flooded (anaerobic) and non-flooded (aerobic) California watershed conditions. Under aerobic conditions the degradation rate constant (k=0.0084 ± 0.0039 day(-1)) and DT50 (82...
October 4, 2017: Chemosphere
https://www.readbyqxmd.com/read/29031119/index-analysis-and-human-health-risk-model-application-for-evaluating-ambient-air-heavy-metal-contamination-in-chemical-valley-sarnia
#2
Richard Olawoyin, Linda Schweitzer, Kuangyuan Zhang, Oladapo Okareh, Kevin Slates
The impacts of air emissions as a consequence of industrial activities around communities of human habitation have been extensively reported. This study is the first to assess potential adverse human health effects in the Chemical Valley Sarnia (CVS) area, around the St. Clair River, using health risk models, ecological and pollution indices. Large quantities of particulate matters (PM) are generated from anthropogenic activities, which contain several heavy metals in trace quantities with potentially adverse effects to humans and environmental health...
October 11, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/29028539/electrospun-polycaprolactam-manganese-oxide-fiber-for-headspace-solid-phase-microextraction-of-phthalate-esters-in-water-samples
#3
Niloufar Eskandarpour, Hassan Sereshti
The nanofibrous polycaprolactam (polyamide 6 (PA6)) incorporated with manganese oxide (MnO) nanoparticles was fabricated by electrospinning and used as a new fiber coating for headspace-solid phase microextraction (HS-SPME) of the selected phthalate esters (PEs) in water samples prior to GC-μECD. The adsorbent was fully characterized using scanning electron microscopy (SEM), Fourier transform-infrared (FT-IR) spectroscopy and thermogravimetric analysis (TGA). The main parameters that affect the HS-SPME efficiency such as extraction temperature, ionic strength, extraction and desorption times were investigated...
October 5, 2017: Chemosphere
https://www.readbyqxmd.com/read/29028407/synthesis-of-carboxylated-styrene-polymer-for-internal-calibration-of-fourier-transform-ion-cyclotron-resonance-mass-spectrometry-of-humic-substances
#4
Alexander Zherebker, Alexandra V Turkova, Yury Kostyukevich, Alexey Kononikhin, Kirill V Zaitsev, Igor A Popov, Eugene Nikolaev, Irina V Perminova
We report synthesis and application of the novel carboxylated styrene for internal calibration of Fourier transform ion cyclotron resonance mass-spectra of humic substances. The calibrant was synthesized in five steps from acetylsalicylic acid (aspirin) followed by spontaneous polymerization of vinyl salicylic acid. Aromatic nature of the prepared polymer enabled its simultaneous analysis in the presence of the Suwannee River fulvic acid without using dual-spray approach. The major advantage of the calibrant proposed in this study is a lack of suppression of humic substances signals and maintenance of peak intensity distribution...
August 2017: European Journal of Mass Spectrometry
https://www.readbyqxmd.com/read/29027996/aquatic-urban-ecology-at-the-scale-of-a-capital-community-structure-and-interactions-in-street-gutters
#5
Vincent Hervé, Boris Leroy, Albert Da Silva Pires, Pascal Jean Lopez
In most cities, streets are designed for collecting and transporting dirt, litter, debris, storm water and other wastes as a municipal sanitation system. Microbial mats can develop on street surfaces and form microbial communities that have never been described. Here, we performed the first molecular inventory of the street gutter-associated eukaryotes across the entire French capital of Paris and the non-potable waters sources. We found that the 5782 OTUs (operational taxonomic units) present in the street gutters which are dominated by diatoms (photoautotrophs), fungi (heterotrophs), Alveolata and Rhizaria, includes parasites, consumers of phototrophs and epibionts that may regulate the dynamics of gutter mat microbial communities...
October 13, 2017: ISME Journal
https://www.readbyqxmd.com/read/29024585/n-s-p-co-doped-carbon-nanodot-fabricated-from-waste-microorganism-and-its-application-for-label-free-recognition-of-manganese-vii-and-%C3%AA-ascorbic-acid-and-and-logic-gate-operation
#6
Xiaojuan Gong, Zengbo Li, Qin Hu, Ruixin Zhou, Shaomin Shuang, Chuan Dong
A novel fluorescent probe based on N,S,P co-doped carbon nanodots (N,S,P-CNDSac) has been facile and fast fabricated by a one-step hydrothermal pyrolysis of Saccharomyces cerevisiae and utilized for label-free and "on-off-on" sequential detection manganese(VII) and ʟ-ascorbic acid (ʟ-AA). The fluorescence of N,S,P-CNDSac can be effectively quenched by Mn(VII) based on inner filter effect (IFE) and recovered upon the addition of ʟ-AA due to the easy-conversion of Mn(VII) to reduced states (i.e. Mn(IV), Mn(II) and Mn(0)) by ʟ-AA...
October 12, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/29023517/developmental-delay-in-the-amazon-the-social-determinants-and-prevalence-among-rural-communities-in-peru
#7
Christopher Westgard, Yossef Alnasser
The consequences of poor child development are becoming increasingly recognized. Programs are being put in place around the world to improve child development by providing healthy and stimulating environments for children. However, these programs often have limited reach and little is known about the prevalence of developmental delay in under-developed communities. The current study set-out to better understand the prevalence of developmental delay in rural communities in the Amazon region of Peru. Also, it explores social determinants that are associated with any delay...
2017: PloS One
https://www.readbyqxmd.com/read/29023503/model-uncertainties-do-not-affect-observed-patterns-of-species-richness-in-the-amazon
#8
Lilian Patrícia Sales, Olívia Viana Neves, Paulo De Marco, Rafael Loyola
BACKGROUND: Climate change is arguably a major threat to biodiversity conservation and there are several methods to assess its impacts on species potential distribution. Yet the extent to which different approaches on species distribution modeling affect species richness patterns at biogeographical scale is however unaddressed in literature. In this paper, we verified if the expected responses to climate change in biogeographical scale-patterns of species richness and species vulnerability to climate change-are affected by the inputs used to model and project species distribution...
2017: PloS One
https://www.readbyqxmd.com/read/29023062/biodegradation-of-quinalphos-by-a-soil-bacterium-bacillus-subtilis
#9
Venkata Subba Reddy Gangireddygari, DileepKumar Kanderi, Ramanjaneyulu Golla, Manjunatha Bangeppagari, Vijay Anand Kumar Babu Gundi, Khayalethu Ntushelo, Rajasekhar Reddy Bontha
BACKGROUND AND OBJECTIVE: A widely used pesticide quinalphos (O, O-diethyl O-quinoxalin-2-yl phosphorothioate) may be an undesirable and persistent pollutant to non-target environments like rivers and other ecosystems. The objective of this study was to isolate a potential degradant bacterium of quinalphos from polluted soils and test its fitness under various culture conditions. MATERIALS AND METHODS: A soil bacterium strain, capable of utilizing quinalphos as its sole source of carbon and energy was isolated from soil by enrichment method on a minimal salts medium (MSM)...
2017: Pakistan Journal of Biological Sciences: PJBS
https://www.readbyqxmd.com/read/29023058/morphometric-characteristics-of-asian-catfish-hemibagrus-wyckii-bleeker-1858-bagridae-from-the-riau-province-of-indonesia
#10
Netti Aryani, Saberina Hasibuan, Ainul Mardiah, Hafrijal Syandri
BACKGROUND AND OBJECTIVE: Asian Catfish (Hemibagrus wyckii) is an important fish having both food and a high price in the market. These species are categorized as a carnivorous freshwater finfish native in Indonesia and is vulnerable to endangered status. This study was carried out to identify the morphometric characteristics of Hemibagrus wyckii (H. wyckii) from the Koto Panjang Reservoir, Kampar Kanan and Kampar Kiri rivers. MATERIALS AND METHODS: Twenty-five fish were collected from each sampling site...
2017: Pakistan Journal of Biological Sciences: PJBS
https://www.readbyqxmd.com/read/29023015/evaluation-of-growth-performances-of-some-locally-farmed-maize-zea-mays-l-in-cross-river-state-nigeria-under-different-concentrations-of-silicon
#11
M O Ononyume, E A Edu, T Okoh, A P Inegbedion
OBJECTIVE: Growth performances of four maize varieties (91 SUWANI, TZL COMP 4, DT STR Y SYN 2 and IWO SYN C2) were investigated at four levels of silicon concentration (0, 2500, 5000 and 7500 mg, with 0 mg as control). METHODOLOGY: Viable seeds were planted in polythene bags (64 bags) containing soil in a randomized complete block design (a 4×4 factorial experiment) with four replications. Plant height, stem girth, leaf area and leaf number were evaluated at 4, 6, 8 and 10 weeks after planting...
2017: Pakistan Journal of Biological Sciences: PJBS
https://www.readbyqxmd.com/read/29022581/the-impact-of-rare-variation-on-gene-expression-across-tissues
#12
Xin Li, Yungil Kim, Emily K Tsang, Joe R Davis, Farhan N Damani, Colby Chiang, Gaelen T Hess, Zachary Zappala, Benjamin J Strober, Alexandra J Scott, Amy Li, Andrea Ganna, Michael C Bassik, Jason D Merker, Ira M Hall, Alexis Battle, Stephen B Montgomery
Rare genetic variants are abundant in humans and are expected to contribute to individual disease risk. While genetic association studies have successfully identified common genetic variants associated with susceptibility, these studies are not practical for identifying rare variants. Efforts to distinguish pathogenic variants from benign rare variants have leveraged the genetic code to identify deleterious protein-coding alleles, but no analogous code exists for non-coding variants. Therefore, ascertaining which rare variants have phenotypic effects remains a major challenge...
October 11, 2017: Nature
https://www.readbyqxmd.com/read/29022146/cupriavidus-malaysiensis-sp-nov-a-novel-poly-3-hydroxybutyrate-co-4-hydroxybutyrate-accumulating-bacterium-isolated-from-the-malaysian-environment
#13
Hema Ramachandran, Nur Asilla Hani Shafie, Kumar Sudesh, Mohamad Noor Azizan, Mohamad Isa Abdul Majid, Al-Ashraf Abdullah Amirul
Bacterial classification on the basis of a polyphasic approach was conducted on three poly(3 hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] accumulating bacterial strains that were isolated from samples collected from Malaysian environments; Kulim Lake, Sg. Pinang river and Sg. Manik paddy field. The Gram-negative, rod-shaped, motile, non-sporulating and non-fermenting bacteria were shown to belong to the genus Cupriavidus of the Betaproteobacteria on the basis of their 16S rRNA gene sequence analyses...
October 11, 2017: Antonie Van Leeuwenhoek
https://www.readbyqxmd.com/read/29021541/trade-routes-and-plague-transmission-in-pre-industrial-europe
#14
Ricci P H Yue, Harry F Lee, Connor Y H Wu
Numerous historical works have mentioned that trade routes were to blame for the spread of plague in European history, yet this relationship has never been tested by quantitative evidence. Here, we resolve the hypothetical role of trade routes through statistical analysis on the geo-referenced major trade routes in the early modern period and the 6,656 geo-referenced plague outbreak records in AD1347-1760. Ordinary Least Square (OLS) estimation results show that major trade routes played a dominant role in spreading plague in pre-industrial Europe...
October 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29020641/assessing-membrane-biofouling-and-its-gel-layer-of-anoxic-oxic-membrane-bioreactor-for-megacity-municipal-wastewater-treatment-during-plum-rain-season-in-yangtze-river-delta-china
#15
Lijie Zhou, Biao Ye, Siqing Xia
This study assessed membrane biofouling and its gel layer of anoxic/oxic membrane bioreactor (A/O-MBR) for megacity municipal wastewater treatment during plum rain season, which was continuous rainy weather, in Yangtze River Delta, China. A laboratory-scale A/O-MBR was operated to treat the municipal wastewater from Quyang wastewater treatment plant, which located at the typical megacity of Shanghai in Yangtze River Delta, from April to July accompanying with plum rain season. As reactor performance showed, CODCr, NH4(+)-N, TN, TP of the influent gradually decreased during plum rain season, and inhibited pollutant removal due to organic carbon shortage...
October 5, 2017: Water Research
https://www.readbyqxmd.com/read/29020640/bridging-spatially-segregated-redox-zones-with-a-microbial-electrochemical-snorkel-triggers-biogeochemical-cycles-in-oil-contaminated-river-tyne-uk-sediments
#16
Carolina Cruz Viggi, Bruna Matturro, Emanuela Frascadore, Susanna Insogna, Alessio Mezzi, Saulius Kaciulis, Angela Sherry, Obioma K Mejeha, Ian M Head, Eleni Vaiopoulou, Korneel Rabaey, Simona Rossetti, Federico Aulenta
Marine sediments represent an important sink for a number of anthropogenic organic contaminants, including petroleum hydrocarbons following an accidental oil spill. Degradation of these compounds largely depends on the activity of sedimentary microbial communities linked to biogeochemical cycles, in which abundant elements such as iron and sulfur are shuttled between their oxidized and reduced forms. Here we show that introduction of a small electrically conductive graphite rod ("the electrochemical snorkel") into an oil-contaminated River Tyne (UK) sediment, so as to create an electrochemical connection between the anoxic contaminated sediment and the oxygenated overlying water, has a large impact on the rate of metabolic reactions taking place in the bulk sediment...
October 3, 2017: Water Research
https://www.readbyqxmd.com/read/29020189/the-macrofilaricidal-efficacy-of-repeated-doses-of-ivermectin-for-the-treatment-of-river-blindness
#17
Martin Walker, Sébastien D S Pion, Hanwei Fang, Jacques Gardon, Joseph Kamgno, Maria-Gloria Basáñez, Michel Boussinesq
Background: Mass drug administration (MDA) with ivermectin is the cornerstone of efforts to eliminate human onchocerciasis by 2020/2025. The feasibility of elimination crucially depends on the effects of multiple ivermectin doses on Onchocerca volvulus. A single ivermectin (standard) dose clears the skin-dwelling microfilarial progeny of adult worms (macrofilariae) and temporarily impedes the release of such progeny by female macrofilariae, but a macrofilaricidal effect has been deemed minimal...
July 19, 2017: Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America
https://www.readbyqxmd.com/read/29020032/linking-functional-response-and-bioenergetics-to-estimate-juvenile-salmon-growth-in-a-reservoir-food-web
#18
Craig A Haskell, David A Beauchamp, Stephen M Bollens
Juvenile salmon (Oncorhynchus spp.) use of reservoir food webs is understudied. We examined the feeding behavior of subyearling Chinook salmon (O. tshawytscha) and its relation to growth by estimating the functional response of juvenile salmon to changes in the density of Daphnia, an important component of reservoir food webs. We then estimated salmon growth across a broad range of water temperatures and daily rations of two primary prey, Daphnia and juvenile American shad (Alosa sapidissima) using a bioenergetics model...
2017: PloS One
https://www.readbyqxmd.com/read/29019928/the-abundance-of-toxic-genotypes-is-a-key-contributor-to-anatoxin-variability-in-phormidium-dominated-benthic-mats
#19
Susanna A Wood, Jonathan Puddick
The prevalence of benthic proliferations of the anatoxin-producing cyanobacterium Phormidium are increasing in cobble-bed rivers worldwide. Studies to date have shown high spatial and temporal variability in anatoxin concentrations among mats. In this study we determined anatoxin quotas (toxins per cell) in field samples and compared these results to the conventionally-used concentrations (assessed per dry weight of mat). Three mats were selected at sites in two rivers and were sampled every 2-3 h for 24-26 h...
October 11, 2017: Marine Drugs
https://www.readbyqxmd.com/read/29019399/ingestion-of-microplastics-by-freshwater-tubifex-worms
#20
Rachel R Hurley, Jamie C Woodward, James J Rothwell
Microplastic contamination of the aquatic environment is a global issue. Microplastics can be ingested by organisms leading to negative physiological impacts. The ingestion of microplastics by freshwater invertebrates has not been reported outside the laboratory. Here we demonstrate the ingestion of microplastic particles by Tubifex tubifex in a major urban waterbody fed by the River Irwell, Manchester, UK. The host sediments had microplastic concentrations ranging from 56 to 2544 particles kg-1. 87% of the Tubifex ingested microplastic particles were microfibres (55 - 4100 µm in length), whilst the remaining 13% were fragments (50 - 4500 µm in length)...
October 11, 2017: Environmental Science & Technology
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