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https://www.readbyqxmd.com/read/28738627/a-novel-ph-probe-based-on-ratiometric-fluorescent-properties-of-dicyanomethylene-4h-chromene-platform
#1
Xiaolei Liu, Jixun Han, Yan Zhang, Xiaofeng Yang, Yu Cui, Guoxin Sun
We report here a ratiometric pH probe (Z)-2-(2-(2-(4-hydroxyphenyl)-2-(pyrrolidin-1-yl)vinyl) -4H-chromen-4-ylidene)-malononitrile over the pH range of 2.44-6.00. It was synthesized by Knoevenagel Reaction from dicyanomethylene-4H-chromene and pyrrolidine. This is the first example of pyrrolidine as a part of the product structure in Knoevenagel condensation. High selectivity and sensitivity for pH variation were observed with significant fluorescent ratiometric responses and a remarkable Stokes shift (about 138nm)...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738511/litter-thickness-but-not-root-biomass-explains-the-average-and-spatial-structure-of-soil-hydraulic-conductivity-in-secondary-forests-and-coffee-agroecosystems-in-veracruz-mexico
#2
B E Marín-Castro, S Negrete-Yankelevich, D Geissert
Secondary forests and coffee agroecosystems are considered good alternatives for conservation of a high capacity for water filtration in the soil where tropical montane cloud forests (TMCF) once grew; however, it is not clear which characteristics of the vegetation modulate the field saturated hydraulic conductivity of the soil (Kfs) and whether these characteristics persist in such derived systems. Here, we explore how changes in vegetation between secondary forests and coffee agroecosystems have consequences for the average value and spatial variation of litter thickness and root biomass, and whether these differences can explain the Kfs and its spatial distribution...
July 18, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28738218/common-variation-in-the-autism-risk-gene-cntnap2-brain-structural-connectivity-and-multisensory-speech-integration
#3
Lars A Ross, Victor A Del Bene, Sophie Molholm, Young Jae Woo, Gizely N Andrade, Brett S Abrahams, John J Foxe
Three lines of evidence motivated this study. 1) CNTNAP2 variation is associated with autism risk and speech-language development. 2) CNTNAP2 variations are associated with differences in white matter (WM) tracts comprising the speech-language circuitry. 3) Children with autism show impairment in multisensory speech perception. Here, we asked whether an autism risk-associated CNTNAP2 single nucleotide polymorphism in neurotypical adults was associated with multisensory speech perception performance, and whether such a genotype-phenotype association was mediated through white matter tract integrity in speech-language circuitry...
July 21, 2017: Brain and Language
https://www.readbyqxmd.com/read/28738213/determinants-of-the-magnitude-of-socioeconomic-inequalities-in-mortality-a-study-of-17-european-countries
#4
Johan P Mackenbach, Matthias Bopp, Patrick Deboosere, Katalin Kovacs, Mall Leinsalu, Pekka Martikainen, Gwenn Menvielle, Enrique Regidor, Rianne de Gelder
The magnitude of socioeconomic inequalities in mortality differs importantly between countries, but these variations have not been satisfactorily explained. We explored the role of behavioral and structural determinants of these variations, by using a dataset covering 17 European countries in the period 1970-2010, and by conducting multilevel multivariate regression analyses. Our results suggest that between-country variations in inequalities in current mortality can partly be understood from variations in inequalities in smoking, excessive alcohol consumption, and poverty...
July 21, 2017: Health & Place
https://www.readbyqxmd.com/read/28738060/community-detection-in-sequence-similarity-networks-based-on-attribute-clustering
#5
Janamejaya Chowdhary, Frank E Löffler, Jeremy C Smith
Networks are powerful tools for the presentation and analysis of interactions in multi-component systems. A commonly studied mesoscopic feature of networks is their community structure, which arises from grouping together similar nodes into one community and dissimilar nodes into separate communities. Here, the community structure of protein sequence similarity networks is determined with a new method: Attribute Clustering Dependent Communities (ACDC). Sequence similarity has hitherto typically been quantified by the alignment score or its expectation value...
2017: PloS One
https://www.readbyqxmd.com/read/28737392/ligand-strain-and-entropic-effects-on-the-binding-of-macrocyclic-and-linear-inhibitors-molecular-modelling-of-penicillopepsin-complexes
#6
Dimas Suarez, Natalia Diaz
Using extensive molecular dynamics simulations, we investigate the structure and dynamics of the complexes formed between penicillopepsin and two peptidomimetic inhibitors: a linear compound, isovaleryl(P4)-valine(P3)-asparagine(P2)-leucine(P1)-phosphonate-phenilalanine(P1'), and its macrocylic analog that includes a methylene bridge between the Asn(P2) and Phe(P1') side chains. The macrocyclic inhibitor, which has a 420-fold larger affinity than that of the acyclic one, has been considered to lower the entropic penalty for binding...
July 24, 2017: Journal of Chemical Information and Modeling
https://www.readbyqxmd.com/read/28737259/homopolymer-nanolithography
#7
Moritz Tebbe, Elizabeth Galati, Gilbert C Walker, Eugenia Kumacheva
Future progress in nanoscience and nanotechnology necessitates further development of versatile, labor-, and cost-efficient surface patterning strategies. A new approach to nanopatterning is reported, which utilizes surface segregation of a smooth layer of an end-grafted homopolymer in a poor solvent. The variation in polymer grafting density yields a range of surface nanostructures, including randomly organized pinned spherical micelles, worm-like structures, networks, and porous films. The capability to use the polymer patterns for site-specific deposition of small molecules, polymers, or nanoparticles is shown...
July 24, 2017: Small
https://www.readbyqxmd.com/read/28736898/identification-of-positive-selection-signatures-in-pigs-by-comparing-linkage-disequilibrium-variances
#8
X Li, S Yang, K Dong, Z Tang, K Li, B Fan, Z Wang, B Liu
Selection affects the patterns of linkage disequilibrium (LD) around the site of a beneficial allele with an increase in LD among the hitchhiking alleles. Comparing the differences in regional LD between pig populations could help to identify putative genomic regions with potential adaptations for economic traits. In this study, using Illumina Porcine SNP60K BeadChip genotyping data from 207 Chinese indigenous, 117 South American village and 408 Large White pigs, we estimated the variation of genome-wide LD between populations using the varld program...
July 23, 2017: Animal Genetics
https://www.readbyqxmd.com/read/28736498/insights-on-glicentin-a-promising-peptide-of-the-proglucagon-family
#9
REVIEW
Juliette Raffort, Fabien Lareyre, Damien Massalou, Patrick Fénichel, Patricia Panaïa-Ferrari, Giulia Chinetti
Glicentin is a proglucagon-derived peptide mainly produced in the L-intestinal cells. While the roles of other members of the proglucagon family including glucagon-like peptide 1, glucagon-like peptide 2 and oxyntomodulin has been well studied, the functions and variation of glicentin in human are not fully understood. Experimental and clinical studies have highlighted its role in both intestinal physiology and glucose metabolism, pointing to its potential interest in a wide range of pathological states including gastrointestinal and metabolic disorders...
June 15, 2017: Biochemia Medica: časopis Hrvatskoga Društva Medicinskih Biokemičara
https://www.readbyqxmd.com/read/28736468/multi-atlas-spleen-segmentation-on-ct-using-adaptive-context-learning
#10
Jiaqi Liu, Yuankai Huo, Zhoubing Xu, Albert Assad, Richard G Abramson, Bennett A Landman
Automatic spleen segmentation on CT is challenging due to the complexity of abdominal structures. Multi-atlas segmentation (MAS) has shown to be a promising approach to conduct spleen segmentation. To deal with the substantial registration errors between the heterogeneous abdominal CT images, the context learning method for performance level estimation (CLSIMPLE) method was previously proposed. The context learning method generates a probability map for a target image using a Gaussian mixture model (GMM) as the prior in a Bayesian framework...
February 11, 2017: Proceedings of SPIE
https://www.readbyqxmd.com/read/28735305/molecular-study-of-indigenous-bacterial-community-composition-on-exposure-to-soil-arsenic-concentration-gradient
#11
Semanti Basu, Tanima Paul, Priya Yadav, Abhijit Debnath, Keka Sarkar
Community structure of bacteria present in arsenic contaminated agricultural soil was studied with qPCR (quantitative PCR) and DGGE (Denaturing Gradient Gel Electrophoresis) as an indicator of extreme stresses. Copy number of six common bacterial taxa (Acidobacteria, Actinobacteria, α-, β- and γ-Proteobacteria, Firmicutes) was calculated using group specific primers of 16S rDNA. It revealed that soil contaminated with low concentration of arsenic was dominated by both Actinobacteria and Proteobacteria but a shift towards Proteobacteria was observed with increasing arsenic concentration, and number of Actinobacteria eventually decreases...
July 6, 2017: Polish Journal of Microbiology
https://www.readbyqxmd.com/read/28735200/ion-specific-hydration-in-nano-confined-electrical-double-layers
#12
Z Zachariah, R M Espinosa-Marzal, M P Heuberger
We probe counter-ion specific effects in nano-confined electrical-double-layers (EDLs) by means of direct force measurements across a model slit pore in the extended surface forces apparatus. By variation of solution composition, we compare four different counter-ions with dissimilar hydration properties, namely Na(+), K(+), Cs(+) as well as H3O(+), all confined between (001) mica surfaces. We discuss the results in terms of a recently proposed π-transition model, evoking hydrated ion layering as the recurrent structural element in highly confined EDLs...
July 14, 2017: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/28734911/plaque-rupture-in-coronary-atherosclerosis-is-associated-with-increased-plaque-structural-stress
#13
Charis Costopoulos, Yuan Huang, Adam J Brown, Patrick A Calvert, Stephen P Hoole, Nick E J West, Jonathan H Gillard, Zhongzhao Teng, Martin R Bennett
OBJECTIVES: The aim of this study was to identify the determinants of plaque structural stress (PSS) and the relationship between PSS and plaques with rupture. BACKGROUND: Plaque rupture is the most common cause of myocardial infarction, occurring particularly in higher risk lesions such as fibroatheromas. However, prospective intravascular ultrasound-virtual histology studies indicate that <10% higher risk plaques cause clinical events over 3 years, indicating that other factors also determine plaque rupture...
July 13, 2017: JACC. Cardiovascular Imaging
https://www.readbyqxmd.com/read/28734842/hydration-forces-between-aligned-dna-helices-undergoing-b-to-a-conformational-change-in-situ-x-ray-fiber-diffraction-studies-in-a-humidity-and-temperature-controlled-environment
#14
Ryan Case, Hauke Schollmeyer, Phillip Kohl, Eric B Sirota, Roger Pynn, Kai E Ewert, Cyrus R Safinya, Youli Li
Hydration forces between DNA molecules in the A- and B-Form were studied using a newly developed technique enabling simultaneous in situ control of temperature and relative humidity. X-ray diffraction data were collected from oriented calf-thymus DNA fibers in the relative humidity range of 98%-70%, during which DNA undergoes the B- to A-form transition. Coexistence of both forms was observed over a finite humidity range at the transition. The change in DNA separation in response to variation in humidity, i...
July 19, 2017: Journal of Structural Biology
https://www.readbyqxmd.com/read/28734753/cranial-bone-structure-in-children-with-sagittal-craniosynostosis-relationship-with-surgical-outcomes
#15
Naiara Rodriguez-Florez, Amel Ibrahim, J Ciaran Hutchinson, Alessandro Borghi, Greg James, Owen J Arthurs, Patrizia Ferretti, David Dunaway, Silvia Schievano, N U Owase Jeelani
BACKGROUND: While spring-assisted cranioplasty has become a widespread technique to correct scaphocephaly in children with sagittal synostosis, predicting head shape changes induced by the gradual opening of the springs remains challenging. This study aimed to explore the role of cranial bone structure on surgical outcomes. METHODS: Patients with isolated sagittal synostosis undergoing spring-assisted cranioplasty at GOSH (London, UK) were recruited (n = 18, age: 3-8 months)...
June 27, 2017: Journal of Plastic, Reconstructive & Aesthetic Surgery: JPRAS
https://www.readbyqxmd.com/read/28734650/treatment-of-cracked-teeth
#16
Shaymaa Alkhalifah, Halimah Alkandari, Prem N Sharma, Alex J Moule
Although many options are proposed for the treatment of cracked posterior teeth, most treatment decisions are not evidence based. Thus, considerable individual variation can occur regarding treatment recommendations for the same scenario. To our knowledge, there are no studies in the literature assessing practitioners' attitudes toward the treatment of cracked teeth. This research recorded variations between general practitioners and specialist groups regarding the treatment approaches of cracked teeth. In a cross-sectional structured questionnaire survey, 32 prosthodontists, 34 endodontists, and 29 general practitioners working in public and private dental health services in Kuwait were assessed regarding their treatment approach to 5 different clinical cracked tooth scenarios...
July 19, 2017: Journal of Endodontics
https://www.readbyqxmd.com/read/28734588/high-throughput-sequencing-analysis-of-bacterial-community-spatiotemporal-distribution-in-response-to-clogging-in-vertical-flow-constructed-wetlands
#17
Guofen Hua, Ying Cheng, Jun Kong, Man Li, Zhongwei Zhao
The aim of this study was to characterize bacterial communities in vertical flow constructed wetlands (VFCWs) using Illumina high-throughput sequencing. The bacterial communities developed lower richness and diversity in response to clogging. Bacterial diversity did not overtly decrease with depth. A variety of bacterial phyla were found in VFCWs' bacterial communities, including Bacteroidetes, Actinobacteria and Acidobacteria, among which Proteobacteria was dominant. At the genus level, a spatiotemporal variation was illustrated in the diversity and structure of bacterial communities...
July 14, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28734531/event-based-control-of-depth-of-hypnosis-in-anesthesia
#18
Luca Merigo, Manuel Beschi, Fabrizio Padula, Nicola Latronico, Massimiliano Paltenghi, Antonio Visioli
BACKGROUND AND OBJECTIVE: In this paper, we propose the use of an event-based control strategy for the closed-loop control of the depth of hypnosis in anesthesia by using propofol administration and the bispectral index as a controlled variable. METHODS: A new event generator with high noise-filtering properties is employed in addition to a PIDPlus controller. The tuning of the parameters is performed off-line by using genetic algorithms by considering a given data set of patients...
August 2017: Computer Methods and Programs in Biomedicine
https://www.readbyqxmd.com/read/28734220/effect-analysis-of-quantum-chemical-descriptors-and-substituent-characteristics-on-henry-s-law-constants-of-polybrominated-diphenyl-ethers-at-different-temperatures
#19
Jiang Long, Qiu Youli, Li Yu
Twelve substituent descriptors, 17 quantum chemical descriptors and 1/T were selected to establish a quantitative structure-property relationship (QSPR) model of Henry's law constants for 7 polybrominated diphenyl ethers (PBDEs) at five different temperatures. Then, the lgH of 202 congeners at different temperatures were predicted. The variation rule and regulating mechanism of lgH was studied from the perspectives of both quantum chemical descriptors and substituent characteristics. The R(2) for modeling and testing sets of the final QSPR model are 0...
July 19, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28734110/when-can-refuges-mediate-the-genetic-effects-of-fire-regimes-a-simulation-study-of-the-effects-of-topography-and-weather-on-neutral-and-adaptive-genetic-diversity-in-fire-prone-landscapes
#20
Sam C Banks, Ian D Davies, Geoffrey J Cary
Understanding how landscape heterogeneity mediates the effects of fire on biodiversity is increasingly important under global changes in fire regimes. We used a simulation experiment to investigate how fire regimes interact with topography and weather to shape neutral and selection-driven genetic diversity under alternative dispersal scenarios, and to explore the conditions under which micro-refuges can maintain genetic diversity of populations exposed to recurrent fire. Spatial heterogeneity in simulated fire frequency occurred in topographically-complex landscapes, with fire refuges and fire-prone 'hotspots' apparent...
July 22, 2017: Molecular Ecology
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