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71.
This paper describes the reaction of the simplest isocyanate, isocyanic acid, conveniently generated in situ from sodium cyanate, with nucleophilic carboxylate and amino residues in polyamide fibres. Changing the pH conditions greatly affects the outcome of these reactions: under acidic conditions the carboxylate residues are selectively carbamoylated, whereas under neutral conditions both residues are carbamoylated. Such modifications greatly change the dyeing behaviour of the treated substrates. The carboxylate carbamoylation reaction leads to the formation of amides rather than the carbamoylcarboxylate, which is a reactive intermediate. 相似文献
72.
Amber L. Pearson Lucy Telfar Barnard Jamie Pearce Simon Kingham Philippa Howden-Chapman 《Building Research & Information》2014,42(2):182-190
There is extensive research on the negative health impacts of poor housing quality. However, little is known about the potential health benefits of high-quality housing in poor neighbourhoods. Neighbourhoods with unexpectedly good health outcomes despite high levels of deprivation have been deemed resilient places and housing quality in these areas may be a contributor to this resilience. This study aimed to evaluate whether an indicator of neighbourhood housing quality was associated with a previously quantified resilience index (RINZ) in New Zealand. It was found that areas with high housing quality tended to have higher median income, greater proportions of partnered people and shorter-term residents, and very low proportions of Māori. A positive association was found between housing quality and resilience, after adjustment for deprivation. There was no indication of differences by heterogeneity in housing quality within the aggregate unit of analysis. These findings pose the hypothesis that improving housing quality in similarly deprived areas that have poor health outcomes could potentially boost health. To extend this understanding, further development of a more sophisticated housing quality indicator is recommended. 相似文献
73.
Dusty R. Miller Jamie E. Spahn J. Herbert Waite 《Journal of the Royal Society Interface》2015,12(111)
The California mussel, Mytilus californianus, adheres in the highly oxidizing intertidal zone with a fibrous holdfast called the byssus using 3, 4-dihydroxyphenyl-l-alanine (DOPA)-containing adhesive proteins. DOPA is susceptible to oxidation in seawater and, upon oxidation, loses adhesion. Successful mussel adhesion thus depends critically on controlling oxidation and reduction. To explore how mussels regulate redox during their functional adhesive lifetime, we tracked extractable protein concentration, DOPA content and antioxidant activity in byssal plaques over time. In seawater, DOPA content and antioxidant activity in the byssus persisted much longer than expected—50% of extractable DOPA and 30% of extractable antioxidant activity remained after 20 days. Antioxidant activity was located at the plaque–substrate interface, demonstrating that antioxidant activity keeps DOPA reduced for durable and dynamic adhesion. We also correlated antioxidant activity to cysteine and DOPA side chains of mussel foot proteins (mfps), suggesting that mussels use both cysteine and DOPA redox reservoirs for controlling interfacial chemistry. These data are discussed in the context of the biomaterial structure and properties of the marine mussel byssus. 相似文献
74.
Manda P Hargett JK Vaka SR Repka MA Murthy SN 《Drug development and industrial pharmacy》2011,37(11):1306-1310
The purpose of this study was to investigate the plausibility of delivery of cefotaxime to the brain via intranasal administration. In vitro permeation studies were carried out using Franz diffusion cells, and the effect of different concentrations of chitosan (0.1% w/v and 0.25% w/v) on drug permeation across the bovine olfactory mucosa was determined. Samples were collected from the receiver compartment at different time points and analyzed using HPLC. The amount of cefotaxime that permeated across the olfactory mucosa when 0.25% w/v of chitosan was used as a permeation enhancer was ~1.5- and ~2-fold higher at the end of the first hour and second hour, respectively, over control (29.56 ± 6.18 μg/cm(2)). There was no significant enhancement in drug permeation when 0.1% w/v chitosan was used as the permeation enhancer. Pharmacokinetic studies were carried out using Sprague-Dawley rats. Cefotaxime solution with 0.25% w/v chitosan (40 mg/kg) was administered intravenously (i.v.) to rats in groups 1 and 3 and intranasally to those in group 2 and 4. The time course of drug in the brain was investigated by performing microdialysis in rats of groups 1 and 2. Blood samples were withdrawn from rats in groups 3 and 4, and cefotaxime in plasma was analyzed using HPLC after extraction with a hydrochloric acid-chloroform:1-pentanol (3:1) and phosphate buffer solvent system. Pharmacokinetic parameters were calculated using the trapezoidal rule. The results imply that the drug levels attained in the brain following i.v. and intranasal administrations were comparable. These results suggest that intranasal administration of cefotaxime could be a potential method of delivering antibacterial agents because of it being noninvasive and patient compliant. 相似文献
75.
This paper describes our recent developments of intermediate-band solar cells, with a focus on the use of dilute alloys and nanostructured materials such as quantum dots (QDs). The concept of"full-spectrum" solar cells and their working mechanism with various material structures based intermediate-band solar cells, including material growth, structural and chemical analysis, device modeling and testing, are presented. Finally, the progress and challenges of quantum-dot-based solar cells are discussed. 相似文献
76.
Radoslaw M. Kowalczyk Patrick J. Murphy Jamie Tibble-Howlings 《International journal of molecular sciences》2022,23(23)
An unusual residual dipolar coupling of methylene protons was recorded in NMR spectra because aromatic zephycandidine has preferential orientation at the external magnetic field. The observed splitting contains contribution from the dipole–dipole D-coupling and the anisotropic component of J-coupling. Absolute values of the anisotropy of magnetic susceptibility |Δχax| are larger for protic solvents because of the hydrogen-bonding compared to aprotic solvents for which polar and dispersion forces are more important. The energy barrier for the reorientation due to hydrogen-bonding is 1.22 kJ/mol in methanol-d4, 0.85 kJ/mol in ethanol-d6 and 0.87 kJ/mol in acetic acid-d6. In dimethyl sulfoxide-d6, 1.08 kJ/mol corresponds to the interaction of solvent lone pair electrons with π-electrons of zephycandidine. This energy barrier decreases for acetone-d6 which has smaller electric dipole moment. In acetonitrile-d3, there is no energy barrier which suggests solvent ordering around the solute due to the solvent-solvent interactions. The largest absolute values of the magnetic anisotropy are observed for aromatic benezene-d6 and tolune-d8 which have their own preferential orientation and enhance the order in the solution. The magnetic anisotropy of “isolated” zephycandidine, not hindered by intermolecular interaction could be estimated from the correlation between Δχax and cohesion energy density. 相似文献
77.
78.
Ladouceur Robert; Ferland Francine; Poulin Christiane; Vitaro Frank; Wiebe Jamie 《Canadian Metallurgical Quarterly》2005,19(3):271
This study assessed the possible differences in the classification of adolescent gamblers when using the South Oaks Gambling Screen-Revised for Adolescents (SOGS-RA; K. C. Winters, R. D. Stinchfield, & J. Fulkerson, 1993) versus a clinical interview that was based on Diagnostic and Statistical Manual of Mental Disorders (DSM-IV; American Psychiatric Association, 1994) criteria for pathological gambling. A total of 631 adolescents ages 15-17 years participated in the two phases of the study. Results revealed that of the 93 adolescents who had been screened as problem gamblers according to the SOGS-RA, only 7 could be clinically confirmed as pathological gamblers according to the criteria used at present to define pathological gambling. The need to clarify the construct of pathological gambling among youth is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
Murphy K van Ginneken B Reinhardt JM Kabus S Ding K Deng X Cao K Du K Christensen GE Garcia V Vercauteren T Ayache N Commowick O Malandain G Glocker B Paragios N Navab N Gorbunova V Sporring J de Bruijne M Han X Heinrich MP Schnabel JA Jenkinson M Lorenz C Modat M McClelland JR Ourselin S Muenzing SE Viergever MA De Nigris D Collins DL Arbel T Peroni M Li R Sharp GC Schmidt-Richberg A Ehrhardt J Werner R Smeets D Loeckx D Song G Tustison N Avants B Gee JC Staring M Klein S Stoel BC Urschler M 《IEEE transactions on medical imaging》2011,30(11):1901-1920
EMPIRE10 (Evaluation of Methods for Pulmonary Image REgistration 2010) is a public platform for fair and meaningful comparison of registration algorithms which are applied to a database of intrapatient thoracic CT image pairs. Evaluation of nonrigid registration techniques is a nontrivial task. This is compounded by the fact that researchers typically test only on their own data, which varies widely. For this reason, reliable assessment and comparison of different registration algorithms has been virtually impossible in the past. In this work we present the results of the launch phase of EMPIRE10, which comprised the comprehensive evaluation and comparison of 20 individual algorithms from leading academic and industrial research groups. All algorithms are applied to the same set of 30 thoracic CT pairs. Algorithm settings and parameters are chosen by researchers expert in the configuration of their own method and the evaluation is independent, using the same criteria for all participants. All results are published on the EMPIRE10 website (http://empire10.isi.uu.nl). The challenge remains ongoing and open to new participants. Full results from 24 algorithms have been published at the time of writing. This paper details the organization of the challenge, the data and evaluation methods and the outcome of the initial launch with 20 algorithms. The gain in knowledge and future work are discussed. 相似文献
80.
Adherence rates to ferric citrate as compared to active control in patients with end stage kidney disease on dialysis 下载免费PDF全文
Diana Jalal Molly McFadden Jamie P. Dwyer Kausik Umanath Erwin Aguilar Yoram Yagil Barbara Greco Mohammed Sika Julia B. Lewis Tom Greene Simin Goral 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(2):243-249
Introduction: Oral phosphate binders are the main stay of treatment of hyperphosphatemia. Adherence rates to ferric citrate, a recently approved phosphate binder, are unknown. Methods: We conducted a post‐hoc analysis to evaluate whether adherence rates were different for ferric citrate vs. active control in 412 subjects with end stage kidney disease (ESKD) who were randomized to ferric citrate vs. active control (sevelamer carbonate and/or calcium acetate). Adherence was defined as percent of actual number of pills taken to total number of pills prescribed. Findings: There were no significant differences in baseline characteristics including gender, race/ethnicity, and age between the ferric citrate and active control groups. Baseline phosphorus, calcium, and parathyroid hormone levels were similar. Mean (SD) adherence was 81.4% (17.4) and 81.7% (15.9) in the ferric citrate and active control groups, respectively (P = 0.88). Adherence remained similar between both groups after adjusting for gender, race/ethnicity, age, cardiovascular disease (CVD), and diabetic nephropathy (mean [95% CI]: 81.4% [78.2, 84.6] and 81.5% [77.7, 85.2] for ferric citrate and active control, respectively). Gender, race/ethnicity, age, and diagnosis of diabetic nephropathy did not influence adherence to the prescribed phosphate binder. Subjects with CVD had lower adherence rates to phosphate binder; this was significant only in the active control group. Discussion: Adherence rates to the phosphate binder, ferric citrate, were similar to adherence rates to active control. Similar adherence rates to ferric citrate are notable since tolerance to active control was an entry criteria and the study was open label. Gender, race/ethnicity, nor age influenced adherence. 相似文献