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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/28738622/a-flow-based-procedure-exploiting-the-lab-in-syringe-approach-for-the-determination-of-ester-content-in-biodiesel-and-diesel-biodiesel-blends
#2
Samara Soares, Wanessa R Melchert, Fábio R P Rocha
The ester content is an important parameter to be monitored in biodiesel for evaluation of the transesterification reaction yield and for assessing the purity of the final product. This is also a relevant quality parameter in diesel/biodiesel blends to avoid frauds, because legislation establishes a minimum amount of biodiesel to be added to diesel. The official method EN14103 requires the addition of an alternative internal standard (methyl nonadecanoate) for analysis of biodiesel from bovine tallow because the methyl heptadecanoate is found in high amounts in this product...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738597/sensitive-detection-of-sulfide-based-on-the-self-assembly-of-fluorescent-silver-nanoclusters-on-the-surface-of-silica-nanospheres
#3
Yehan Yan, Kui Zhang, Huan Yu, Houjuan Zhu, Mingtai Sun, Tasawar Hayat, Ahmed Alsaedi, Suhua Wang
Hydrogen sulfide is a toxic and flammable gaseous pollutant often emitted to air as a by-product of water supply, chemical, petroleum and coal industries. It can be transferred into sulfur dioxide in the air under some meteorologic conditions. Herein, we report a novel ratiometric fluorescence method for hydrogen sulfide based on silver nanoclusters and quantum dots. The silver nanoclusters have been self-assemblied onto the surface of silica spheres, which are embedded with red fluorescent quantum dots, to form a dual-emissive nanohybrid...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738582/metaboqc-a-tool-for-correcting-untargeted-metabolomics-data-with-mass-spectrometry-detection-using-quality-controls
#4
Mónica Calderón-Santiago, María A López-Bascón, Ángela Peralbo-Molina, Feliciano Priego-Capote
Nowadays most metabolomic studies involve the analysis of large sets of samples to find a representative metabolite pattern associated to the factor under study. During a sequence of analyses the instrument signals can be subjected to the influence of experimental variability sources. Implementation of quality control (QC) samples to check the contribution of experimental variability is the most common approach in metabolomics. This practice is based on the filtration of molecular entities experiencing a variation coefficient higher than that measured in the QC data set...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738553/response-of-soil-physicochemical-properties-and-enzyme-activities-to-long-term-reclamation-of-coastal-saline-soil-eastern-china
#5
Xuefeng Xie, Lijie Pu, Qiqi Wang, Ming Zhu, Yan Xu, Meng Zhang
Soil enzyme activity during different years of reclamation and land use patterns could indicate changes in soil quality. The objective of this research is to explore the dynamics of 5 soil enzyme activities (dehydrogenase, amylase, urease, acid phosphatase and alkaline phosphatase) involved in C, N, and P cycling and their responses to changes in soil physicochemical properties resulting from long-term reclamation of coastal saline soil. Soil samples from a total of 55 sites were collected from a coastal reclamation area with different years of reclamation (0, 7, 32, 40, 63a) in this study...
July 20, 2017: Science of the Total Environment
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
#6
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/28738458/-associations-between-season-of-birth-and-age-both-at-menarche-and-at-menopause
#7
J H Si, R R Meng, J Lyu, Y Guo, Z Bian, C Q Yu, L Yang, Y L Tan, P Pei, J S Chen, Z M Chen, L M Li
Objective: To examine the associations between season of birth and factors as age at menarche, age at menopause and reproductive span. Methods: A total of 285 186 female from the China Kadoorie Biobank, with complete data on critical variables and had menarche at 9-18 years old, were included. A total of 132 373 female with natural menopause were included for the analysis on age at menopause and reproductive span. Multiple linear regression models were used to assess the associations of birth season and the age at menarche, menopause, and reproductive span...
July 10, 2017: Zhonghua Liu Xing Bing Xue za Zhi, Zhonghua Liuxingbingxue Zazhi
https://www.readbyqxmd.com/read/28738457/-survey-of-economic-burden-of-hepatitis-b-related-diseases-in-12-areas-in-china
#8
Q S Ma, S Liang, H W Xiao, S X Zhang, G H Zhuang, Y H Zou, H Z Tan, J C Liu, Y H Zhang, A Q Xu, L Zhang, X X Feng, D S Hu, F Z Wang, F Q Cui, X F Liang
Objective: Less surveys on the economic burden of hepatitis B (HB)-related diseases have been conducted in China, so the socioeconomic harm caused by the diseases is not clear and the key parameters for economic evaluation of hepatitis B prevention and treatment are lacking. This study aimed to analyze the direct, indirect and intangible expenditures of hospitalized patients with HB-related diseases during hospitalization and during a year in different areas of China. Methods: The hospitals for infectious diseases and the large general hospitals in 12 areas in China were selected in the study...
July 10, 2017: Zhonghua Liu Xing Bing Xue za Zhi, Zhonghua Liuxingbingxue Zazhi
https://www.readbyqxmd.com/read/28738420/variation-in-the-three-dimensional-histomorphometry-of-the-normal-human-optic-nerve-head-with-age-and-race-lamina-cribrosa-and-peripapillary-scleral-thickness-and-position
#9
Christopher A Girkin, Massimo A Fazio, Hongli Yang, Juan Reynaud, Claude F Burgoyne, Brandon Smith, Lan Wang, J Crawford Downs
Purpose: This study quantified the thickness and depth of the lamina cribrosa (LC) and peripapillary scleral thickness in high-resolution three-dimensional (3D) fluorescent reconstructions of the optic nerve head (ONH) in eyes from donors of African (AD) and European descent (ED). Methods: A total of 64 eyes (45 ED, 19 AD) from 51 normal donors were obtained within 6 hours of death and fixed at 10 mm Hg of pressure. The optic nerve head was trephined from the globe and digitally reconstructed at 1...
July 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/28738384/sweet-taste-perception-and-dental-caries-in-13-to-15-year-olds-a-multicenter-cross-sectional-study
#10
H Ashi, C Lara-Capi, G Campus, G Klingberg, P Lingström
Dietary habits and, in particular, the intake frequency of sucrose are of major importance for the development of dental caries. The perception of sweet taste is believed to have an influence on sucrose intake and therefore affects the predisposition to dental caries. The aim was to study the caries experience and sweet taste perception and to further analyze the possible relationship between the 2 tested variables in 13- to 15-year-old children from 3 different geographical areas. A cross-sectional survey comprising 669 children (220 Italian, 224 Mexican, and 225 Saudi Arabian) was conducted...
July 25, 2017: Caries Research
https://www.readbyqxmd.com/read/28738273/factors-influencing-warfarin-control-in-australia-and-singapore
#11
Nijole Bernaitis, Chi Keong Ching, Siew Chong Teo, Liping Chen, Tony Badrick, Andrew K Davey, Julia Crilly, Shailendra Anoopkumar-Dukie
INTRODUCTION: Warfarin is widely used for patients with non-valvular atrial fibrillation (NVAF). Variations in warfarin control, as measured by time in therapeutic range (TTR), have been reported across different regions and ethnicities, particularly between Western and Asian countries. However, there is limited data on comparative factors influencing warfarin control in Caucasian and Asian patients. Therefore, the aim of this study was to determine warfarin control and potential factors influencing this in patients with NVAF in Australia and Singapore...
July 14, 2017: Thrombosis Research
https://www.readbyqxmd.com/read/28738218/common-variation-in-the-autism-risk-gene-cntnap2-brain-structural-connectivity-and-multisensory-speech-integration
#12
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/28738217/association-between-an-indel-polymorphism-in-the-3-utr-of-col1a2-and-the-risk-of-sudden-cardiac-death-in-chinese-populations
#13
Zhixia Yin, Yadong Guo, Jianhua Zhang, Qing Zhang, Lijuan Li, Shouyu Wang, Chaoqun Wang, Yan He, Shaohua Zhu, Chengtao Li, Suhua Zhang, Lagabaiyila Zha, Jifeng Cai, Bin Luo, Yuzhen Gao
Sudden cardiac death (SCD) describes the unexpected natural death from a cardiac cause within a short time period. Compelling evidence suggests the involvement of host genetic factors in SCD etiology. Identification of genetic variations predisposed to SCD enables genetic testing that may contribute to SCD diagnosis and risk stratification. Previous studies have suggested that dysregulation of pro-alpha2 chain of type I collagen, encoded by collagen type I alpha 2 chain (COL1A2) gene, was involved in cardiac disorders such as myocardial infarction, hypertrophic cardiomyopathy and atherosclerosis...
July 19, 2017: Legal Medicine
https://www.readbyqxmd.com/read/28738213/determinants-of-the-magnitude-of-socioeconomic-inequalities-in-mortality-a-study-of-17-european-countries
#14
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/28738189/surgical-landmarks-to-locating-the-main-trunk-of-the-facial-nerve-in-parotid-surgery-a-systematic-review
#15
Yisi D Ji, R Bruce Donoff, Zachary S Peacock, Eric R Carlson
PURPOSE: The purpose of this study was to describe distances from commonly used anatomic landmarks to the main trunk of the facial nerve during parotid surgery. MATERIALS AND METHODS: A systematic search of the published literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. All studies from January 1, 1990 to January 1, 2017 that measured distances to the main trunk of the facial nerve from common anatomic landmarks were eligible...
June 30, 2017: Journal of Oral and Maxillofacial Surgery
https://www.readbyqxmd.com/read/28738151/effect-of-headgroup-variation-on-the-self-assembly-of-cationic-surfactants-with-sulfonatocalix-6-arene
#16
Véronique Wintgens, József Gábor Harangozó, Zsombor Miskolczy, Jean-Michel Guigner, Catherine Amiel, Laszlo Biczok
The effect of headgroup variation on the association of supramolecular amphiphiles composed of 4-sulfonatocalix[6]arene (SCX6) and cationic surfactant possessing tetradecyl substituent was studied in aqueous solutions at pH 7. When the surfactant contained hydrophilic trimethylammonium, pyridinium, or 1-methylimidazolium headgroup, highly reversible temperature-responsive nanoparticle-supramolecular micelle transformation could be attained at appropriately chosen component mixing ratios and NaCl concentrations...
July 24, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28738137/public-health-and-economic-consequences-of-vaccine-hesitancy-for-measles-in-the-united-states
#17
Nathan C Lo, Peter J Hotez
Importance: Routine childhood vaccination is declining in some regions of the United States due to vaccine hesitancy, which risks the resurgence of many infectious diseases with public health and economic consequences. There are ongoing policy debates on the state and national level, including legislation around nonmedical (personal-belief) exemptions for childhood vaccination and possibly a special government commission on vaccine safety, which may affect vaccine coverage. Objective: To estimate the number of measles cases in US children and the associated economic costs under scenarios of different levels of vaccine hesitancy, using the case example of measles, mumps, and rubella (MMR) vaccination and measles...
July 24, 2017: JAMA Pediatrics
https://www.readbyqxmd.com/read/28738077/consequences-of-severe-habitat-fragmentation-on-density-genetics-and-spatial-capture-recapture-analysis-of-a-small-bear-population
#18
Sean M Murphy, Ben C Augustine, Wade A Ulrey, Joseph M Guthrie, Brian K Scheick, J Walter McCown, John J Cox
Loss and fragmentation of natural habitats caused by human land uses have subdivided several formerly contiguous large carnivore populations into multiple small and often isolated subpopulations, which can reduce genetic variation and lead to precipitous population declines. Substantial habitat loss and fragmentation from urban development and agriculture expansion relegated the Highlands-Glades subpopulation (HGS) of Florida, USA, black bears (Ursus americanus floridanus) to prolonged isolation; increasing human land development is projected to cause ≥ 50% loss of remaining natural habitats occupied by the HGS in coming decades...
2017: PloS One
https://www.readbyqxmd.com/read/28738060/community-detection-in-sequence-similarity-networks-based-on-attribute-clustering
#19
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/28738031/perioperative-care-implementation-evidence-based-practice-for-patients-with-pancreaticoduodenectomy-using-the-enhanced-recovery-after-surgery-guidelines-%C3%A2
#20
Cesar Aviles, Marilyn Hockenberry, Dionisios Vrochides, David Iannitti, Allyson Cochran, Kendra Tezber, Misty Eller, Janet Desamero
BACKGROUND: Pancreatic adenocarcinoma is an aggressive cancer that carries a poor prognosis. Pancreaticoduodenectomy (PD) offers the only potential cure, but the associated morbidity is high. The Enhanced Recovery After Surgery (ERAS) evidence-based guidelines for perioperative care for PD can be used to reduce variations in practice.
. OBJECTIVES: The primary aim was to evaluate the feasibility of the ERAS guidelines for patients undergoing PD. Secondary aims were to assess length of stay (LOS), readmission within 30 days, 30-day mortality, and total surgical complication rates...
August 1, 2017: Clinical Journal of Oncology Nursing
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