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https://www.readbyqxmd.com/read/29935494/elucidating-the-mass-spectrum-of-the-retronecine-alkaloid-using-dft-calculations
#1
Lucas Modesto-Costa, Sabrina T Martinez, Angelo C Pinto, Ricardo Vessecchi, Itamar Borges
Pyrrolizidine alkaloids are natural molecules playing important roles in different biochemical processes in nature and in humans. In this work, the electron ionization mass spectrum (EI-MS) of retronecine, an alkaloid molecule found in plants, is investigated computationally. Its mass spectrum can be characterized by three main fragment ions having the following m/z ratios: 111, 94 and 80. In order to rationalize the mass spectrum, minima and transition state geometries were computed using density functional theory (DFT)...
June 23, 2018: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/29935489/a-comparison-study-of-the-detection-of-bloodstains-on-painted-and-cleaned-surfaces-with-luminol
#2
Valentina Brenzini, Rahul Pathak
There seems to be a limited amount of research about the detection of concealed bloodstains on painted surfaces. The bloodstains on walls and floors are often removed by cleaning, in some cases the surfaces are painted by the perpetrator after committing a violent crime in order to hide the crime that has occurred. The study hereafter extends and deepens on previous researches by investigating the detectability of horse bloodstains on painted ceramic tiles as a function of the number of layers of paint. In this study luminol was used as a reagent to detect the bloodstains...
April 27, 2018: Forensic Science International
https://www.readbyqxmd.com/read/29935476/a-molecular-dynamics-simulation-study-of-amino-acid-selectivity-of-leurs-editing-domain-from-thermus-thermophilus
#3
Alexey Rayevsky, Mohsen Sharifi, Michael Tukalo
The accuracy of protein synthesis is provided by the editing functions of aminoacyl-tRNA synthetases (aaRSs), a mechanism that eliminates misactivated amino acids or mischarged tRNAs. Despite research efforts, some molecular bases of these mechanisms are still unclear. The post-transfer editing pathway of leucyl-tRNA synthetase (LeuRS) carried out in a special insertion domain (the Connective Polypeptide 1 or CP1), as editing domain. Recently, it was shown by in vivo studies and was supported by mutagenesis, and the kinetics approaches that the CP1 domain of LeuRS has discriminatory power for different substrates...
June 18, 2018: Journal of Molecular Graphics & Modelling
https://www.readbyqxmd.com/read/29935470/fourteen-month-olds-selectively-search-for-and-use-information-depending-on-the-familiarity-of-the-informant-in-both-laboratory-and-home-contexts
#4
Andy Schieler, Melissa Koenig, David Buttelmann
Infants are selective in their learning from others. However, there is only very limited research on the possible factors that shape this selectivity, especially when it comes to the impact of infants' familiarity with the informant and the context. The current study investigated whether 14-month-olds preferred to receive and use information provided by an unfamiliar informant (experimenter) compared with a familiar informant (parent) and whether this pattern depended on the context (home vs. laboratory). We tested infants either in the laboratory (n = 67) or in their home (n = 70)...
June 20, 2018: Journal of Experimental Child Psychology
https://www.readbyqxmd.com/read/29935467/dissolution-of-realgar-by-acidithiobacillus-ferrooxidans-in-the-presence-and-absence-of-zerovalent-iron-implications-for-remediation-of-iron-deficient-realgar-tailings
#5
Lijun Fan, Fenghua Zhao, Jing Liu, Karen A Hudson-Edwards
Realgar (As4 S4 )-rich tailings are iron-deficient arsenical mine wastes. The mechanisms and products of the dissolution of realgar by Acidithiobacillus ferrooxidans (A. ferrooxidans) in the presence (0.2 g and 2 g) and absence of zerovalent iron (ZVI) are investigated for three stages (each of 7 d with fresh A. ferrooxidans medium addition between the stages). SEM-EDX, FTIR, XPS and selective extraction analysis are used to characterize the solid-phase during the experiments. ZVI addition causes the systems to become more acid-generating, although pH increases are observed in the first day due to ZVI dissolution...
June 6, 2018: Chemosphere
https://www.readbyqxmd.com/read/29935465/a-novel-active-passive-sampling-approach-for-measuring-time-averaged-concentrations-of-pollutants-in-water
#6
Elvio D Amato, Adrian Covaci, Raewyn M Town, Jonas Hereijgers, Ben Bellekens, Valentina Giacometti, Tom Breugelmans, Maarten Weyn, Freddy Dardenne, Lieven Bervoets, Ronny Blust
Passive sampling with in situ devices offers several advantages over traditional sampling methods (i.e., discrete spot sampling), however, data interpretation from conventional passive samplers is hampered by difficulties in estimating the thickness of the diffusion layer at the sampler/medium interface (δ), often leading to inaccurate determinations of target analyte concentrations. In this study, the performance of a novel device combining active and passive sampling was investigated in the laboratory. The active-passive sampling (APS) device is comprised of a diffusion cell fitted with a pump and a flowmeter...
June 14, 2018: Chemosphere
https://www.readbyqxmd.com/read/29935464/low-concentration-exposure-to-glyphosate-based-herbicide-modulates-the-complexes-of-the-mitochondrial-respiratory-chain-and-induces-mitochondrial-hyperpolarization-in-the-danio-rerio-brain
#7
Aline G Pereira, Michael L Jaramillo, Aline P Remor, Alexandra Latini, Carla E Davico, Mariana L da Silva, Yara M R Müller, Dib Ammar, Evelise M Nazari
Glyphosate (N-phosphonomethyl-glycine) (GLY) is the active ingredient of the most used herbicides in the world. GLY is applied in formulated products known as glyphosate-based herbicides (GBH), which could induce effects that are not predicted by toxicity assays with pure GLY. This herbicide is classified as organophosphorus compound, which is known to induce neurotoxic effects. Although this compound is classified as non-neurotoxic by regulatory agencies, acute exposure to GBH causes neurological symptoms in humans...
June 11, 2018: Chemosphere
https://www.readbyqxmd.com/read/29935460/equine-sperm-bound-antisperm-antibodies-are-associated-with-poor-semen-quality
#8
M S Ferrer, L M J Miller
Antisperm antibodies (ASAs) have been associated with infertility in stallions. The objectives of this study were to investigate the frequency of ASA-positive semen samples in satisfactory and non-satisfactory breeder stallions, the association between ASA binding and semen quality, and factors that may affect the diagnosis. Breeding soundness examinations were performed in 21 stallions and the percentage of IgG- and IgA-bound spermatozoa was evaluated using flow cytometry. Median IgG and IgA binding did not differ between the first and second ejaculates...
June 1, 2018: Theriogenology
https://www.readbyqxmd.com/read/29935457/photocatalytic-enhancement-of-cesium-removal-by-prussian-blue-deposited-tio-2
#9
Hyuncheol Kim, Minsun Kim, Wooyul Kim, Wanno Lee, Soonhyun Kim
After the Fukushima nuclear accident, tremendous efforts were made to treat radiocesium, radiostrontium, and other radioactive materials. For the first time, we demonstrate that a TiO2 photocatalyst can significantly enhance Cs adsorption by Prussian blue-deposited TiO2 (PB/TiO2 ) under UV irradiation. In this study, we synthesized PB/TiO2 using the photodeposition method. After the Cs ions were adsorbed on the PB/TiO2 in darkness, we then exposed the PB/TiO2 to UV light irradiation. This resulted in a further increase in Cs ion adsorption of more than 10 times the amount adsorbed in darkness...
June 19, 2018: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/29935450/the-effects-of-environmental-conditions-on-the-enrichment-of-antibiotics-on-microplastics-in-simulated-natural-water-column
#10
Xian-Cheng Shen, De-Chang Li, Xiao-Feng Sima, Hui-Yuan Cheng, Hong Jiang
Concerns regarding the release of microplastics (MPs) into the environment led us to explore the relationship between the different environmental factors and physicochemical properties of MPs, as well as the change of interaction between MPs and organic pollutants. In this study, the effects of environmental factors (ageing conditions), such as pH, temperature, ionic strength, ageing time, and humic acid (HA) concentration, on the characteristics of MPs and their adsorption toward tetracycline (TC) were systematically investigated...
June 20, 2018: Environmental Research
https://www.readbyqxmd.com/read/29935447/integrated-hydro-environmental-impact-assessment-and-alternative-selection-of-low-impact-development-practices-in-small-urban-catchments
#11
Yang Yang, Ting Fong May Chui
Attention is increasingly being paid to low impact development (LID) practices in urban stormwater management. Because LID practices offer a wide variety of hydro-environmental benefits, it is often necessary to account for these benefits collectively in cost-benefit analysis and LID alternative selection. The conventional methods of quantifying these benefits, however, can hardly incorporate the preferences of decision makers, and commonly involve tedious parameter estimations. To address these shortcomings, this study adopts a relative performance evaluation method to assess the various hydro-environmental impacts of LID alternatives in small urban catchments...
June 20, 2018: Journal of Environmental Management
https://www.readbyqxmd.com/read/29935445/selective-recovery-of-salt-from-coal-gasification-brine-by-nanofiltration-membranes
#12
Kun Li, Wencheng Ma, Hongjun Han, Chunyan Xu, Yuxing Han, Dexin Wang, Weiwei Ma, Hao Zhu
The selective extraction and concentration of salt from coal gasification brine (CGB) by nanofiltration membranes is a promising technology to achieve near-zero liquid discharge of coal gasification wastewater. To investigate the feasibility of recovery of salts and the interaction of organic compounds, multivalent ions and monovalent ions on the rejection ratio, three nanofiltration membranes (OWNF1, NF270 and Desal-5 DK) with an 1812 spiral-wound module were used in crossflow filtration. The rejection mechanism was analyzed by comparing the rejection performance as a function of the operation pressure (increasing from 1...
June 20, 2018: Journal of Environmental Management
https://www.readbyqxmd.com/read/29935440/higher-fasting-plasma-glucose-is-associated-with-smaller-striatal-volume-and-poorer-fine-motor-skills-in-a-longitudinal-cohort
#13
Tianqi Zhang, Marnie E Shaw, Erin I Walsh, Perminder S Sachdev, Kaarin J Anstey, Nicolas Cherbuin
Previous studies have demonstrated associations between higher blood glucose and brain atrophy and functional deficits, however, little is known about the association between blood glucose, striatal volume and striatal function despite sensori-motor deficits being reported in diabetes. This study investigated the relationship between blood glucose levels, striatal volume and fine motor skills in a longitudinal cohort of cognitively healthy individuals living in the community with normal or impaired fasting glucose or type 2 diabetes...
June 7, 2018: Psychiatry research. Neuroimaging
https://www.readbyqxmd.com/read/29935431/biotransformation-and-responses-of-antioxidant-enzymes-in-hydroponically-cultured-soybean-and-pumpkin-exposed-to-perfluorooctane-sulfonamide-fosa
#14
Shuyan Zhao, Tiankun Liang, Tao Zhou, Dongqi Li, Bohui Wang, Jingjing Zhan, Lifen Liu
Perfluorooctane sulfonamide (FOSA) is an important perfluorooctane sulfonate (PFOS) precursor used for commercial applications. In order to investigate the transformation and responses of selected antioxidant and degradation enzymes of FOSA in the plants, in vivo exposure of soybean (Glycine max L. Merrill) and pumpkin (Cucurbita maxima L.) were conducted in the solution-plant microcosms. FOSA was readily taken up by soybean and pumpkin roots and translocated to shoots, and metabolized to PFOS, perfluorohexane sulfonate (PFHxS) and perfluorobutane sulfonate (PFBS)...
June 20, 2018: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/29935430/integration-of-chemical-and-toxicological-tools-to-assess-the-bioavailability-of-copper-derived-from-different-copper-based-fungicides-in-soil
#15
Quan-Ying Wang, Jing-Yue Sun, Xing-Jian Xu, Hong-Wen Yu
Because the extensive use of Cu-based fungicides, the accumulation of Cu in agricultural soil has been widely reported. However, little information is known about the bioavailability of Cu deriving from different fungicides in soil. This paper investigated both the distribution behaviors of Cu from two commonly used fungicides (Bordeaux mixture and copper oxychloride) during the aging process and the toxicological effects of Cu on earthworms. Copper nitrate was selected as a comparison during the aging process...
June 20, 2018: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/29935425/deriving-predicted-no-effect-concentrations-pnecs-for-emerging-contaminants-in-the-river-po-italy-using-three-approaches-assessment-factor-species-sensitivity-distribution-and-aquatox-ecosystem-modelling
#16
Andrea Gredelj, Alberto Barausse, Laura Grechi, Luca Palmeri
Over the past decades, per- and polyfluoroalkyl substances (PFASs) found in environmental matrices worldwide have raised concerns due to their toxicity, ubiquity and persistence. A widespread pollution of groundwater and surface waters caused by PFASs in Northern Italy has been recently discovered, becoming a major environmental issue, also because the exact risk for humans and nature posed by this contamination is unclear. Here, the Po River in Northern Italy was selected as a study area to assess the ecological risk posed by perfluoroalkyl acids (PFAAs), a class of PFASs, considering the noticeable concentration of various PFAAs detected in the Po waters over the past years...
June 20, 2018: Environment International
https://www.readbyqxmd.com/read/29935424/human-papillomavirus-16-e6-modulates-the-expression-of-mir-496-in-oropharyngeal-cancer
#17
Dayna Mason, Xiaoying Zhang, Tânia Monteiro Marques, Barbara Rose, Samantha Khoury, Meredith Hill, Fiona Deutsch, J Guy Lyons, Margarida Gama-Carvalho, Nham Tran
Human papillomavirus (HPV), notably type 16, is a risk factor for up to 75% of oropharyngeal squamous cell carcinomas (SCC). It has been demonstrated that small non-coding RNAs known as microRNAs play a vital role in the cellular transformation process. In this study, we used an LNA array to further investigate the impact of HPV16 on the expression of microRNAs in oropharyngeal (tonsillar) cancer. A number of miRNAs were found to be deregulated, with miR-496 showing a four-fold decrease. Over-expression of the high risk E6 oncoprotein down-regulated miR-496, impacting upon the post-transcriptional control of the transcription factor E2F2...
June 20, 2018: Virology
https://www.readbyqxmd.com/read/29935421/mendelian-randomisation-in-type-2-diabetes-and-coronary-artery-disease
#18
REVIEW
Timothy M Frayling, Charli E Stoneman
Type 2 diabetes, coronary artery disease and hypertension are associated with anthropometric and biomarker traits, including waist-to-hip-ratio, body mass index and altered glucose and insulin levels. Clinical trials, for example of weight-loss interventions, show these factors are causal, but lifelong impact of subtle changes in body mass index and body fat distribution are less clear. The use of human genetics can quantify the causal effects of long-term exposure to subtle changes of modifiable risk factors...
June 20, 2018: Current Opinion in Genetics & Development
https://www.readbyqxmd.com/read/29935420/inducement-of-a-spontaneously-wrinkled-polydimethylsiloxane-surface-and-its-potential-as-a-cell-culture-substrate
#19
Da Som Kim, Ho Won Lee, Jong Hyun Lee, Hyuck Gi Kwon, Sang Wook Lee, Seung Jin Han, Ok Chan Jeong
Spontaneous wrinkling of a polydimethylsiloxane (PDMS) surface was induced by repeated thermal shrinkage of liquid PDMS coated onto a cured PDMS layer. We investigated and evaluated the potential of the resulting surface as a cell culture substrate by monitoring the viability, spreading area, and proliferation rate of MG-63 cells cultured on native, wrinkled, and poly-L-lysine (PLL)-coated PDMS surfaces. Cells seeded on the wrinkled and PLL-coated PDMS surfaces spread and adhered better than those on native surfaces...
June 18, 2018: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/29935418/mechanism-of-light-dependent-biosynthesis-of-silver-nanoparticles-mediated-by-cell-extract-of-neochloris-oleoabundans
#20
Zeqing Bao, Christopher Q Lan
This study investigated the role of chlorophyll and light in the biosynthesis of silver nanoparticles (AgNPs) using disrupted cell aqueous extract of Neochloris oleoabundans. It was found that, while increasing sonication time increased the percentage of disrupted cells and efficiency of aqueous cell extraction, over-sonication reduced AgNPs production. AgNPs biosynthesis required illumination of white, blue, or purple light while AgNPs formation was undetectable under dark condition or illumination of orange or red light, indicating only photons of high energy levels among the photosynthetic active radiations are capable of exciting the electrons of chlorophylls to a state that is sufficient for Ag+ reduction...
June 4, 2018: Colloids and Surfaces. B, Biointerfaces
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