Notes

Aspects Linked to the Variations Involving Self-Report Smoking cigarettes along with Urinary : Cotinine Standards.
These findings contribute to the synthesis of efficient visible-light-driven Bi-based photocatalysts and to the understanding of photocatalytic degradation reactions. Metabolic uncouplers inhibit biofilm and biofouling formation in membrane bioreactor (MBR) systems, which have been considered as a potential biofouling control alternative. To better understand the inhibitory mechanism of uncoupler on biofouling, this study investigated the impact of the uncoupler 3, 3', 4', 5-tetrachlorosalicylanilide (TCS) on biofilm formation of B. subtilis in different development stages. Significant reductions in both the initial bacterial attachment stage and the subsequent biofilm development stage were caused by TCS at 100 μg/L. The motility of B. subtilis in semisolid medium was inhibited by TCS, which explicitly explained the reduction in initial bacterial attachment. Meanwhile, a reduction of extracellular polymeric substance (EPS) secretion owing to TCS suggested why biofilm development was suppressed. In addition, the fluorescent materials in tight-bound EPS (TB-EPS) and loose-bound EPS (LB-EPS) of Bacillus subtilis cultured in different TCS concentrations were distinguished and quantified by three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy coupled with parallel factor analysis (PARAFAC). The results of this study suggested that the biofilm inhibitory mechanism of the uncoupler was both a inhibition in bacterial motor ability and a reduction in EPS secretion. Overwhelming growth of bacterial biofilms on different metal-based pipeline materials are intractable and pose a serious threat to public health when tap water flows though these pipelines. Indeed, the underlying mechanism of biofilm growth on the surface of different pipeline materials deserves detailed exploration to provide subsequent implementation strategies for biofilm control. Thus, in this study, how bacteria response to their encounters was explored, when they inhabit different metal-based pipeline substrates. Results revealed that bacteria proliferated when they grew on stainless steel (SS) and titanium sheet (Ti), quickly developing into bacterial biofilms. In contrast, the abundance of bacteria on copper (Cu) and nickel foam (Ni) substates decreased sharply by 4-5 logs within 24 h. The morphological shrinkage and shortening of bacterial cells, as well as a sudden 64-fold increase of carbohydrate content in extracellular polymeric substances (EPS), were observed on Cu substrate. Furthermore, generation of reactive oxygen species and fluctuation of enzymatic activity demonstrated the destruction of redox equilibrium in bacteria. Bacteria cultured on Cu substrate showed the strongest response, followed by Ni, SS and Ti. The oxidative stress increased quickly during the growth of bacterial biofilm, and almost all tested metal transporter-related genes were upregulated by 2-11 folds on Cu, which were higher than on other substrates (1-2 folds for SS and Ti, 2-9 folds for Ni). Finally, these behaviors were compared under the biofilm regulatory molecular network. This work may facilitate better understanding different response mechanisms during bacterial biofilm colonization on metal-based pipelines and provide implications for subsequent biofilm control. Persistent halogenated compounds (PHCs), including dichlorodiphenyltrichloroethane and its metabolites (DDTs), polybrominated diphenyl ethers (PBDEs), alternative brominated flame retardants (ABFRs), and dechlorane plus (DP), were analyzed in muscle of six bird species from the South China Sea. DDTs, with concentrations up to 19,000 ng/g lipid weight (lw), were the dominant contaminants contributing to 66-99% of PHCs in birds. Concentrations of PBDEs, ABFRs, and DP ranged from 1.1 to 130, 0.73-40, and 0.21-2.5 ng/g lw, respectively. Historically pollution of DDTs and flame retardants in surrounding Asian lands were the main sources for PHCs in birds. BDE 209 was the primary PBDE congener in all birds. 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE) and decabromodiphenyl ethane (DBDPE) were the main ABFRs. Anti-DP and p,p'-DDE were the dominating compounds of DP and DDTs, respectively. Only concentrations of BDEs 153, 203, 196, and 207, p,p'-DDE, and p,p'-DDD showed significant and positive correlations with δ15N values in samples. The resident birds, red-footed booby (Sula sula), had much lower levels of p,p'-DDE and most of PBDEs than those in migratory birds from the South China Sea. Results of stable isotope ratios of carbon suggest the highly variable food items for the five migratory bird species. The abundance of DBDPE in red-footed booby might be related with the ingestion of plastic debris, which still warrants further verification. The Bis(2-ethylhexyl)phthalate (DEHP), a widespread plasticizer, is considered an endocrine disrupting chemical with main toxicological effects on reproductive and metabolic systems. Human biomonitoring (HBM) studies are promoted to evaluate the background exposure levels. In the frame of LIFE PERSUADED project, the HBM study measured DEHP main metabolites (mono-(2-ethylhexyl) phthalate, MEHP; 2-ethyl-5-hydroxy-hexylphthalate, MEHHP; 2-ethyl-5-oxo-hexylphthalate, MEOHP) in Italian children and adolescent (4-14 years old) according to geographical macro-areas and areas, age and sex. Children from the South and the Centre of Italy showed higher median levels of DEHP, as a sum of its metabolites (48.14 and 47.80 μg/L), than those from the North (39.47 μg/L; p = 0.0090 and 0.0004, respectively). Considering the total population, boys are more exposed than girls (only as urinary volume), and children aged 4-6 years have higher median levels than those 7-10 and 11-14 years old. The derived reference values (RV95) for DEHP in children is 168 μg/L. The relative metabolic rates of DEHP, the background levels and, thus, the RV95, vary with the geographical area, age and sex, indicating that all these parameters should be considered in the risk assessment. Solar-driven reduction of CO2 and H2O into fuels is a promising approach for addressing global warming and energy crisis. Herein, Cu+ doped W18O49 nanowires were prepared by a facile solvothermal method and applied in photocatalytic reduction of CO2. The composition and structure of pristine and Cu+ doped W18O49 samples have been characterized. It was found that the morphology of W18O49 nanowires was changed with increasing amounts of dopant. The photocatalytic CO2 reduction activity of W18O49 nanowires and the Cu+ doped W18O49 samples were evaluated using H2O as reducing agent. The strategy of Cu+ doping not only could affect the band edge position and the surface wettability, but also influenced separation of the photogenerated electron-hole pairs. It was found that Cu+ doping could introduce oxygen vacancy and change the conduction edge to a more negative position for W18O49 nanowires, which might be beneficial for the activation of CO2 and promote the following CO2 reduction. Furthermore, the higher separation efficiency of photogenerated electron-hole pairs with Cu+ doping could contribute to the CO2 photoreduction enhancement. In addition, the Cu+ doped W18O49 nanowires (Cu-W18O49-0.005) presented a relatively poor hydrophilic property, which might be beneficial for the adsorption of CO2 molecules and contribute to its superior photocatalytic CO2 reduction capability. The influence of CO, CO2, H2O, H2 and CH4 adsorption on the stability and electronic properties of negative electron affinity (NEA) GaAs nanowire surfaces activated by Cs/O and Cs/NF3 are systematically investigated via first-principles. The calculations indicated that GaAs nanowires activated with 3Cs/O are more susceptible to the surface contamination. After residual gas molecule adsorption, 3Cs/O activated surfaces exhibit direct bandgap character, while 3Cs/NF3 activated surfaces are inversely indirect bandgap. In addition, residual gas adsorption results in a notable increase of band gap, work function and electron affinity of GaAs nanowire surfaces. The incoporation of residual gas molecules also induces a new electric dipole [Cs-gas] with a direction from Cs to gas molecule. From the perspective of theoretical calculation, it is predicted that GaAs nanowires activated through Cs/NF3 has a stronger stability compared with Cs/O in the aspect of gas exposure. Three-dimensionally macroporous (3DM) MnZrOx catalysts were fabricated to reveal the structure and Zr-doping effects on both physicochemical properties and propane combustion behaviors. The increasing addition of zirconium is favorable for the formation of 3DM structure and amorphous Mn-Zr solid solution, leading to tunable physicochemical properties. The significant activity improvement after zirconium addition was originally attributable to the superior redox ability, higher oxygen mobility and more abundant oxygen vacancy. The excellent catalytic activity, cycling stability and water resistant ability over 3DM Mn0.6Zr0.4Ox make it a promising material for hydrocarbons elimination. The comparative TPSR, in situ DRIFTs and kinetics study over 3DM and bulk catalysts emphasize the advantageous function of 3DM architecture on promoting propane adsorption, oxidation and lattice oxygen mobility. Youth with perinatally-acquired HIV (PHIV) experience specific and global cognitive deficits at increased rates compared to typically-developing HIV-uninfected youth. In youth with PHIV, HIV infects the brain early in development. Neuroimaging studies have demonstrated altered grey matter morphometry in youth with PHIV compared to typically-developing youth. This study examined cortical thickness, surface area, and gyrification of grey matter in youth (age 11-20 years old) with PHIV (n = 40) from the Pediatric HIV/AIDS Cohort Study (PHACS) compared to typically-developing presumed HIV uninfected and unexposed youth (n = 80) from the Pediatric Imaging, Neurocognition and Genetics Study (PING) using structural magnetic resonance imaging. This study also examined the relationship between grey matter morphometry and age. Youth with PHIV had reduced cortical thickness, surface area, and gyrification compared to typically-developing youth. In addition, an inverse relationship between age and grey matter volume was found in typically-developing youth, but was not observed in youth with PHIV. Longitudinal studies are necessary to understand the neurodevelopmental trajectory of youth with PHIV. Mesial temporal lobe epilepsy (TLE) is characterized by transient abnormal electrical activity originating in the hippocampus. The objective of this study was to characterize dynamic spatio-temporal fluctuations in hippocampal network connectivity in mTLE using functional connectivity (FC) mapping in 41 unilateral mTLE patients (28 right, 13 left) and 56 healthy control participants using 3T MRI. Dynamic FC was computed across the scan using sliding 60-s windows. This was compared to static FC computed using the whole 10-min functional MRI scan, and to the variance in the hippocampal functional MRI signal. Four states of healthy hippocampal dynamic FC were identified and compared to TLE patients. TLE patients fluctuated between these four states, but the hippocampus ipsilateral to the seizure focus spent more time in a state distinguished by lower prefrontal and parietal FC than the dominant healthy state. Increased time spent in this state was associated with increased impairment in static FC and increased variance in the hippocampal functional MRI signal.
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