bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid LC‐MRM‐MS assay for simultaneous quantification of choline, betaine, trimethylamine, trimethylamine N‐oxide, and creatinine in human plasma and urine
Authors: Zhao Xueqing , Zeisel Steven H , Zhang Shucha 
Published: June 2015

There is a growing interest in analyzing choline, betaine, and their gut microbial metabolites including trimethylamine (TMA) and trimethylamine N‐oxide (TMAO) in body fluids due to the high relevance of these compounds for human health and diseases. A stable isotope dilution (SID)‐LC‐MRM‐MS assay was developed for the simultaneous determination of choline, betaine, TMA, TMAO, and creatinine in human plasma and urine. The assay was validated using quality control (QC) plasma samples, spiked at low, medium, and high levels. Freeze‐thaw stability was also evaluated. The utility of this assay for urine was demonstrated using a nutritional clinical study on the effect of various egg doses on TMAO production in humans. This assay has a wide dynamic range (R2 > 0.994) for all the analytes (choline: 0.122–250 μM; betaine: 0.488–1000 μM; TMA: 0.244–250 μM; TMAO: 0.061–62.5 μM; and creatinine: 0.977–2000 μM). High intra‐ and inter‐day precision (CV < 6%) and high accuracy (< 15% error) were observed from the QC plasma samples. The assay is reliable for samples undergoing multiple freeze‐thaw cycles (tested up to eight cycles). The assay also works for urine samples as demonstrated by a clinical study in which we observed a significant, positive linear response to various egg doses for urinary concentrations of all the analytes except creatinine. A rapid SID‐LC‐MRM‐MS assay for simultaneous quantification of choline, betaine, TMA, TMAO, and creatinine has been developed and validated, and is expected to find wide application in nutrition and cardiovascular studies as well as diagnosis and management of trimethylaminuria.
Combined use of l‐alanine tert butyl ester lactate and trimethyl‐β‐cyclodextrin for the enantiomeric separations of 2‐arylpropionic acids nonsteroidal anti‐inflammatory drugs
Authors: Mavroudi Maria C. , Kapnissi‐Christodoulou Constantina P. 
Published: June 2015

In this study, a new CE method, employing a binary system of trimethyl‐β‐CD (TM‐β‐CD) and a chiral amino acid ester‐based ionic liquid (AAIL), was developed for the chiral separation of seven 2‐arylpropionic acid nonsteroidal anti‐inflammatory drugs (NSAIDs). In particular, the enantioseparation of ibuprofen, ketoprofen, carprofen, indoprofen, flurbiprofen, naproxen, and fenoprofen was improved significantly by supporting the BGE with the chiral AAIL l‐alanine tert butyl ester lactate (l‐AlaC4Lac). Parameters, such as concentrations of TM‐β‐CD and l‐AlaC4Lac, and buffer pH, were systematically examined in order to optimize the chiral separation of each NSAID. It was observed that the addition of the AAIL into the BGE improved both resolution and efficiency significantly. After optimization of separation conditions, baseline separation (Rs>1.5) of five of the analytes was achieved in less than 11 min, while the resolution of ibuprofen and flurbiprofen was approximately 1.2. The optimized enantioseparation conditions for all analytes involve a BGE of 5 mM sodium acetate/acetic acid (pH 5.0), an applied voltage of 30 kV, and a temperature of 20°C. In addition, the results obtained by computing the %‐RSD values of the EOF and the two enantiomer peaks, demonstrated excellent run‐to‐run, batch‐to‐batch, and day‐to‐day reproducibilities.
Hydrogen Evolution Reaction in a Large‐Scale Reactor using a Carbon Nitride Photocatalyst under Natural Sunlight Irradiation
Authors: Schröder Marc , Kailasam Kamalakanan , Borgmeyer Julian , Neumann Maximilian , Thomas Arne , Schomäcker Reinhard , Schwarze Michael 
Published: June 2015

AbstractIn this study, we show the first hydrogen evolution performed in a large‐scale photoreactor under natural sunlight irradiation with a mesoporous carbon nitride photocatalyst immobilized on nine stainless steel plates by drop‐coating. Stable films were obtained producing approximately 18 L gaseous hydrogen within one month time on stream at an average hydrogen evolution reaction (HER) rate of 0.22 L kWh−1. The rate could be nicely predicted from preliminary lab‐scale experiments under well‐defined conditions. Furthermore, the hydrogen production correlates with the sunlight intensity. Based on the total energy input, a maximum solar‐to‐hydrogen (STH) conversion of 0.12 % was obtained.
Sensitive imaging of magnetic nanoparticles for cancer detection by active feedback MR
Authors: Li Zhao , Hsu Chao‐Hsiung , Dimitrov Nikolay , Hwang Dennis W. , Chang Hsin‐Wei , Hwang Lian‐Pin , Lin Yung‐Ya 
Published: June 2015

PurposeSensitive imaging of superparamagnetic nanoparticles or aggregates is of great importance in MR molecular imaging and medical diagnosis. For this purpose, a conceptually new approach, termed active feedback magnetic resonance, was developed.MethodsIn the presence of the Zeeman field, a dipolar field is induced by the superparamagnetic nanoparticles or aggregates. Such dipolar field creates spatial and temporal (due to water diffusion) variations to the precession frequency of the nearby water 1H magnetization. Sensitive imaging of magnetic nanoparticles or aggregates can be achieved by manipulating the intrinsic spin dynamics by selective self‐excitation and fixed‐point dynamics under active feedback fields.ResultsPhantom experiments of superparamagnetic nanoparticles; in vitro experiments of brain tissue with blood clots; and in vivo mouse images of colon cancers, with and without labeling by magnetic nanoparticles, suggest that this new approach provides enhanced, robust, and positive contrast in imaging magnetic nanoparticles or aggregates for cancer detection.ConclusionThe spin dynamics originated from selective self‐excitation and fixed‐point dynamics under active feedback fields have been shown to be sensitive to dipolar fields generated by magnetic nanoparticles. Magn Reson Med 74:33–41, 2015. © 2014 Wiley Periodicals, Inc.
Occupational Therapy Interventions in Chronic Pain – A Systematic Review
Authors: Hesselstrand Malin , Samuelsson Kersti , Liedberg Gunilla 
Published: June 2015

AbstractThe use of interventions based on the best available evidence in occupational therapy is essential, and evaluation of research is part of an evidence‐based practice. The aim of this study was to assess the quality of studies describing and evaluating the effects of occupational therapy interventions on chronic pain. A systematic review of studies with diverse designs was carried out. A quality assessment was conducted, and the level of evidence was defined using the Research Pyramid Model. Of 19 included studies, three received the highest evidence level, and three were considered to be of high quality. The clinical recommendations that can be derived from this study are the following: occupational therapy interventions should start from the identified needs of the person with chronic pain; no support exists for the effectiveness of electromyographic biofeedback training as a supplement, more studies are needed to confirm this result; the efficacy of instructions on body mechanics was significant during work‐hardening treatment; and occupational therapists need to perform and present more clinical studies of high quality and high‐evidence level to build up a trustworthy arsenal of evidence‐based interventions, for example, in persons with chronic pain. Copyright © 2015 John Wiley & Sons, Ltd.
Maternal mosaicism for a large segmental duplication of 18q as a secondary finding following non‐invasive prenatal testing and implications for test accuracy
Authors: Flowers Nicola , Kelley Joanne , Sigurjonsson Styrmir , Bruno Damien L. , Pertile Mark D. 
Published: June 2015

What's already known about this topic?

Non‐invasive prenatal testing (NIPT) of cell‐free DNA from maternal plasma is a sensitive method of identifying pregnancies at risk of trisomies 21, 18 and 13.
This technology analyses both maternal and fetal cell‐free DNA in the maternal plasma.
Abnormal NIPT results should be confirmed with invasive testing.
What does this study add?

Structural imbalances of fetal chromosomes may be identified occasionally during NIPT.
Maternal mosaicism for an unbalanced structural chromosomal rearrangement may be a rare cause of increased risk NIPT results.
Degradable poly(ester triazole)s based on renewable resources
Authors: Hakkou Khalid , Bueno‐Martínez Manuel , Molina‐Pinilla Inmaculada , Galbis Juan A. 
Published: June 2015

ABSTRACTThe copper(I)‐catalyzed alkyne‐azide cycloaddition (CuAAC) click polymerization has been used to obtain novel linear poly(ester triazole)s by reaction ofbis‐alkyne having ester linkage andbis‐azido monomers, most of them derived from carbohydrates, such as glucose, arabinose, and erythrose, and therefore coming from natural renewable resources. The resulting polyesters had weight‐average molecular weights in the 11,500–148,000 range and were characterized by GPC, IR, and NMR spectroscopies. Thermal studies revealed them to be amorphous and stable up to 200 °C under nitrogen. Degradation studies showed that they were hydrolytically degradable. These studies were carried out at 50 °C in phosphate buffer solution at pH 7.4, and were monitored by GPC, and NMR spectroscopy. Finally, novel network hydrogels were obtained by crosslinking reaction of the poly(ester triazole) chains with hexamethylene diisocyanate. The water absorption and the kinetic parameters of the networks were studied. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2015,53, 2481–2493
The effect of amide solvent structure on the direct arylation polymerization (DArP) of 2‐Bromo‐3‐hexylthiophene
Authors: Rudenko Andrey E. , Thompson Barry C. 
Published: June 2015

ABSTRACTIn this work, we investigate the influence of the amide solvent chemical structure on the properties of poly(3‐hexylthiophene) (P3HT) prepared via direct arylation polymerization (DArP). Our findings indicate that for successful polymerization the amide must possess an acyclic aliphatic structure since cyclization of an amide results in a complete shutdown of DArP reactivity as evidenced by failed polymerization in N‐methylpyrrolidone, whereas the presence of an aromatic motif renders the amide solvent susceptible to CH activation and leads to incorporation of the solvent structure into the P3HT backbone, as demonstrated on the example of N,N‐diethylbenzamide. Additionally, we observed that the steric bulk of alkyl substituents on both the nitrogen atom and the carbonyl group within the amide structure has to be delicately balanced for optimal DArP reactivity. In the optimal cases, P3HT is obtained in high yield, with high molecular weight and contains a minimal amount of structural defects. The obtained polymer samples were comprehensively studied in terms of their chemical structure, optical, thermal and solid‐state properties in thin films using GPC analysis, 1H NMR, MALDI, UV–vis, GIXRD spectroscopy, and DSC. We additionally note a drastic difference of the amide solvent effect between DArP and Stille polymerization. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2494–2500
Satisfaction with support versus size of network: differential effects of social support on psychological distress in parents of pediatric cancer patients
Authors: Harper Felicity W. K. , Peterson Amy M. , Albrecht Terrance L. , Taub Jeffrey W. , Phipps Sean , Penner Louis A. 
Published: June 2015

AbstractObjectiveThis study examined the direct and buffering effects of social support on longer‐term global psychological distress among parents coping with pediatric cancer. In both sets of analyses, we examined whether these effects depended on the dimension of social support provided (i.e., satisfaction with support versus size of support network).MethodParticipants were 102 parents of pediatric cancer patients. At study entry, parents reported their trait anxiety, depression, and two dimensions of their social support network (satisfaction with support and size of support network). Parents subsequently reported their psychological distress in 3‐ and 9‐month follow‐up assessments.ResultsParents' satisfaction with support had a direct effect on longer‐term psychological distress; satisfaction was negatively associated with distress at both follow‐ups. In contrast, size of support network buffered (moderated) the impact of trait anxiety and depression on later distress. Parents with smaller support networks and higher levels of trait anxiety and depression at baseline had higher levels of psychological distress at both follow‐ups; for parents with larger support networks, there was no relationship.ConclusionSocial support can attenuate psychological distress in parents coping with pediatric cancer; however, the nature of the effect depends on the dimension of support. Whereas interventions that focus on increasing satisfaction with social support may benefit all parents, at‐risk parents will likely benefit from interventions that ensure they have an adequate number of support resources. Copyright © 2015 John Wiley & Sons, Ltd.
Safety of paediatric tracheal intubation after non‐invasive ventilation failure
Authors: Crulli Benjamin , Loron Gauthier , Nishisaki Akira , Harrington Karen , Essouri Sandrine , Emeriaud Guillaume 
Published: June 2015

SUMMARYContext: Non‐invasive ventilation (NIV) is increasingly used in pediatric intensive care units to limit the complications associated with intubation. However, NIV may fail, and the delay in initiating invasive ventilation may be associated with adverse outcomes. The objective of this retrospective study was to evaluate the safety of tracheal intubation after NIV failure. Methods: Consecutive tracheal intubation procedures were prospectively evaluated in our PICU from 01/2011 to 02/2012, as part of the National Emergency Airway Registry for Children (NEAR4KIDS) collaborative. The incidence of severe tracheal intubation associated events (TIAEs, including cardiac arrest, esophageal intubation with delayed recognition, emesis with aspiration, hypotension requiring intervention, laryngospasm, malignant hyperthermia, pneumothorax, and pneumomediastinum) and severe desaturation (below 80% when pre‐intubation saturation was greater than 94%) were recorded prospectively. NIV use before intubation was retrospectively assessed. Results: 100 consecutive intubation events were analyzed, 46 of which followed NIV failure. NIV exposed and non‐exposed groups had different baseline characteristics, with lower weight, more frequent lower airway and lung disorder, and lower PIM2 score at admission in NIV failure patients (all P <0.05). The nasal route for intubation was more frequent in NIV patients (P < 0.01). The incidence of severe TIAE or desaturation was 41% in the NIV failure group and 24% in primarily intubated patients (P = 0.09). Conclusion: Complications occurred in 41% of intubations after NIV failure in this series. Further research is warranted to evaluate strategies to prevent these complications and to identify conditions in which intubation should not be delayed for a trial of NIV. Pediatr Pulmonol. 2016;51:165–172. © 2015 Wiley Periodicals, Inc.
A comparison of invasive and noninvasive ventilation in children less than 1 year of age: A long‐term follow‐up study
Authors: Kherani Tamizan , Sayal Aarti , Al‐Saleh Suhail , Sayal Priya , Amin Reshma 
Published: June 2015

SummaryBackgroundWe report on the long‐term survival of children initiated on invasive and noninvasive positive pressure ventilation (NiPPV) before the age of 1 to assess the safety and efficacy of long‐term ventilation at home.MethodsA chart review was performed of children initiated on long‐term home mechanical ventilation (LTHV) before the age of 1 year, at The Hospital for Sick Children (SickKids), Canada, between January 1991 and April 2014.ResultsWe report on 51 children. Twenty‐five children (49%) received NiPPV and 26 (51%) received invasive mechanical ventilation via tracheostomy (IMV). There was one NiPPV initiation between 1991 and 2001, the rest were in subsequent years. Most children had a “musculoskeletal disorder” in the NiPPV cohort, n = 14 (56%) and a “central nervous system” disorder in the IMV cohort, n = 13 (50%). The pCO2 improved with the initiation of NiPPV, P = <0.0001. Of the 25 subjects initiated on NiPPV, eight (32%) are currently being followed as compared to 22 (84%) in the IMV cohort. Seven (28%) of the NiPPV group were weaned off ventilation as compared to three (11.5%) in the IMV cohort. There were two NiPPV treatment failures. There were more deaths in the NiPPV cohort: eight (32%) versus two (7.6%) in the IMV cohort. Four of the deaths in the NiPPV cohort were in children in whom a palliative approach was taken. None were due to NiPPV technical failure.ConclusionsBased on this long‐term follow‐up study, NiPPV use in infants appears to be a viable long‐term ventilation strategy. Pediatr Pulmonol. 2016;51:189–195. © 2015 Wiley Periodicals, Inc.
Chronicling Kenyan Asian Diasporic Histories: ‘Newcomers’, ‘Established’ Migrants, and the Post‐Colonial Practices of Time‐Work
Authors: Dickinson Jen 
Published: June 2015

AbstractRecent studies of international migration have observed its increasing complexity. Circular, return, and temporary migration between India and Kenya, arising from the economic and political multipolarities of increasing South‐South partnerships, is one example of such complexity. These flows are distinct from the migration patterns of the longer‐established Kenyan Asian diaspora, who settled under the auspices of the British Empire from the 1890s until the beginning of the 1960s. This paper explores how these transformations are negotiated through the dynamics of Kenyan Asians' ongoing post‐colonial liminalities and ambiguities of citizenship, focusing in particular on the temporal production of distinctions between ‘newcomers’ and ‘established’ migrants, even when in practice these distinctions are much more fluid. This paper highlights the regulatory practices of ‘time‐work’ that enfold the migratory chronologies of ‘established’ migrants into the time of the nation, whilst excluding those of ‘newcomers’. It explores the selective remembering, forgetting, and reworking of the colonial past, a process informed by the dynamics of modernity, diaspora, nation, and postcoloniality in contemporary Kenya. It argues that whilst distinctions between ‘established’ and ‘newcomer’ migrants might reflect different positionings in transnational social fields, differences are also negotiated in contradictions between the experiences, meanings, and understandings of time. This demonstrates how space on its own is itself a inadequate conceptual lens with which to examine relationships between ‘newcomers’ and ‘established’ migrants, and that further research is needed that attends to the temporal dynamics mediating the temporal dissonances of contemporary transnational social fields. Copyright © 2015 John Wiley & Sons, Ltd.
Is Social Mobility Spatial? Characteristics of Immigrant Metros and Second Generation Outcomes: 1940–1970 and 1970–2000
Authors: Goodwin‐White Jamie 
Published: June 2015

AbstractResearch on immigrant and second generation outcomes has often examined their locations, following ideas that geographic dispersion facilitates social mobility, and that characteristics of the ethnic environment enable or constrain progress. I contend that second generation socioeconomic outcomes depend in part on the location choices and characteristics of a previous immigrant generation. Further, I suggest that this relationship reflects the changing geography of immigrants and labour markets, rather than geographically unfolding assimilation. Using the 1940, 1970, and 2000 Integrated Public Use Microdata Series files from the US Census, I regress second and 1.5 generation wage and educational outcomes in 1970 and 2000 on metro‐area characteristics of a previous generation (1940 and 1970, respectively). Current labour market and second generation characteristics are included as controls and to facilitate interpretation. Characteristics of a previous immigrant generation's location were more important for second generation outcomes in the 1940–1970 period, while current place characteristics become more significant by 2000. There is evidence of selection operating through the positive intergenerational effects of places where immigrants' educational levels were high a generation ago. Metro‐level immigrant concentration and manufacturing employment also have generally positive effects, although variations across generations and by nationality suggest their significance for social mobility is inadequately understood. The historical immigrant geographies of the US, and the ways in which metro labour market conditions intersect with immigrants' locational choices, both within and between generations, are thus a critical piece of the economic and spatial assimilation puzzle. Copyright © 2015 John Wiley & Sons, Ltd.
On performance of parametric and distribution‐free models for zero‐inflated and over‐dispersed count responses
Authors: Tang Wan , Lu Naiji , Chen Tian , Wang Wenjuan , Gunzler Douglas David , Han Yu , Tu Xin M. 
Published: June 2015

Zero‐inflated Poisson (ZIP) and negative binomial (ZINB) models are widely used to model zero‐inflated count responses. These models extend the Poisson and negative binomial (NB) to address excessive zeros in the count response. By adding a degenerate distribution centered at 0 and interpreting it as describing a non‐risk group in the population, the ZIP (ZINB) models a two‐component population mixture. As in applications of Poisson and NB, the key difference between ZIP and ZINB is the allowance for overdispersion by the ZINB in its NB component in modeling the count response for the at‐risk group. Overdispersion arising in practice too often does not follow the NB, and applications of ZINB to such data yield invalid inference. If sources of overdispersion are known, other parametric models may be used to directly model the overdispersion. Such models too are subject to assumed distributions. Further, this approach may not be applicable if information about the sources of overdispersion is unavailable.In this paper, we propose a distribution‐free alternative and compare its performance with these popular parametric models as well as a moment‐based approach proposed by Yuet al.[Statistics in Medicine2013;32: 2390–2405]. Like the generalized estimating equations, the proposed approach requires no elaborate distribution assumptions. Compared with the approach of Yuet al., it is more robust to overdispersed zero‐inflated responses. We illustrate our approach with both simulated and real study data. Copyright © 2015 John Wiley & Sons, Ltd.