bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimal Low-Density Lipoprotein Cholesterol Lowering—Morning Versus Evening Statin Administration
Authors: Plakogiannis Roda , Cohen Henry 
Published: January 2007

Objective: To determine the best time to administer statins for optimal lowering of low-density lipoprotein cholesterol (LDL-C) by reviewing the clinical evidence evaluating the chronobiologic effects of morning versus evening statin administration. Data Sources: Using the MeSH terms HMG-CoA reductase inhibitors, statins, morning and evening dosing, and clinical trials, a literature review was conducted to identify articles in MEDLINE (1966–December 2006), International Pharmaceutical Abstracts (1970–Deccmber 2006), and IOWA Drug Information Systems (1985–December 2006). Data Synthesis: Seven English-language studies evaluating morning and evening statin administration were identified and evaluated. Based on the available data, simvastatin demonstrated a pronounced LDL-C percentage reduction with evening closing. Although not statistically significant, a trend in the LDL-C percentage reduction favoring evening statin administration was noted with lovastatin, pravastatin, and rosuvastatin. Atorvastatin demonstrated similar LDL-C reduction regardless of administration time. With the exception of simvastatin, the trials comparing morning versus evening effects of statins on LDL-C have several significant methodologic shortcomings, including small sample size, lack of statistical power, and inappropriate exclusion criteria that did not include or did not mention drug-induced effects on lipids. Conclusions: There are sufficient data to support evening administration of simvastatin to achieve optimal lowering of LDL-C levels. Rigorous and robust trials are necessary to determine the best administration time to achieve optimal LDL-C lowering for lovastatin, pravastatin, rosuvastatin, atorvastatin, and fluvastatin.
Hopeful Thinking and Level of Comfort Regarding Providing Pediatric Palliative Care: A Survey of Hospital Nurses
Authors: Feudtner Chris , Santucci Gina , Feinstein James A. , Snyder C. Rick , Rourke Mary T. , Kang Tammy I. 
Published: January 2007

OBJECTIVE. The purpose of this work was to test the hypothesis that individual nurses' level of hope is associated with greater self-reported comfort and competence in providing palliative care.
METHODS. We conducted a Web-based cross-sectional survey at the Children's Hospital of Philadelphia, a large referral hospital, during the spring of 2005 with all of the employed nurses. The response rate was 44% (410 of 932 eligible nurses). The questions were adapted from published studies or written for this study regarding nurses' knowledge, attitudes, practices, and experiences regarding various aspects of palliative care. We used the Adult Dispositional Hope Scale.
RESULTS. Respondents, asked to rate their degree of agreement (+2, strongly agree to −2, strongly disagree) with the statement that they were “comfortable working with dying children and their families,” reported a mean score of 0.5. Regarding whether they “find it very difficult to talk about death and dying with children and families,” the mean score was −0.1. Nurses specifically reported feeling most competent regarding pain management and least competent regarding talking with children and families about dying. After multivariable adjustment, greater number of years in nursing practice, more hours of palliative care education, and higher scores on the Hope Scale, each were significantly associated with higher levels of comfort working with dying children and the families, lower levels of difficulty talking about death and dying, and higher levels of palliative care competency.
CONCLUSIONS. Nurses' level of hope is associated with their self-reported comfort and competence regarding palliative care.
Improved Neurodevelopmental Outcomes for Extremely Low Birth Weight Infants in 2000–2002
Authors: Wilson-Costello Deanne , Friedman Harriet , Minich Nori , Siner Bonnie , Taylor Gerry , Schluchter Mark , Hack Maureen 
Published: January 2007

BACKGROUND. Neurodevelopmental impairment of extremely low birth weight infants increased in the 1990s. Modern therapeutic changes may have influenced more recent neonatal outcomes.OBJECTIVE. We sought to compare neonatal therapies and outcomes among all extremely low birth weight infants born in 2000–2002 (period III) to 2 previous periods: 1982–1989 (period I) and 1990–1999 (period II).METHODS. The population included 496 extremely low birth weight infants born at our perinatal center during period I, 749 during period II, and 233 during period III. Therapies, rates of death, and survival with and without impairment at 20 months' corrected age were compared.RESULTS. Between periods I and II, survival increased from 49% to 68% as did neonatal morbidity. This resulted in increased survival without impairment but also increased survival with impairment. Changes in therapy during period III included an increase in antenatal steroid use and a decrease in postnatal steroid use, although the rate of chronic lung disease did not change. Sepsis decreased, as did severe intraventricular hemorrhage. On follow-up, the rate of cerebral palsy decreased from 13% to 5%, resulting in a decrease in neurodevelopmental impairment from 35% to 23%. As a result, during period III versus II, survival without impairment increased, whereas survival with impairment decreased.CONCLUSION. Since 2000, neurodevelopmental impairment has decreased among extremely low birth weight infants. A variety of perinatal and neonatal factors were associated with the improved outcomes including increased antenatal steroid use and cesarean section delivery, as well as decreased sepsis, severe cranial ultrasound abnormalities, and postnatal steroid use despite no change in the rate of chronic lung disease.
Adverse Associations of Sleep Problems in Australian Preschoolers: National Population Study
Authors: Hiscock Harriet , Canterford Louise , Ukoumunne Obioha C. , Wake Melissa 
Published: January 2007

OBJECTIVE. In contrast to school-aged children, the impact of sleep problems in preschool-aged children is not well documented. We aimed to determine relationships between preschool-aged child sleep problems and child behavior; health-related quality of life; verbal, preliteracy, and early numeracy skills; diagnosis of attention-deficit/hyperactivity disorder; and injury.PARTICIPANTS AND METHODS. Participants included families (n = 4983) participating in the first wave of the Longitudinal Study of Australian Children, a nationally representative study of Australian children aged 4 to 5 years surveyed from March to November 2004. Measures consisted of a primary caregiver's report of whether their child had a sleep problem (none versus mild versus moderate/severe); specific sleep patterns occurring ≥4 nights per week; health-related quality of life (by using the Pediatric Quality of Life Inventory 4.0); behavior (by using the Strengths and Difficulties Questionnaire) and parent-reported diagnosis of attention-deficit/hyperactivity disorder; and injury requiring medical attention in the past 12 months. Tests of receptive vocabulary and preliteracy/numeracy skills (by using the Who Am I? developmental assessment and the adapted Peabody Picture Vocabulary Test, 3rd Edition) were directly administered to each child.RESULTS. Sleep problems were common, and compared with children without sleep problems, children with sleep problems had poorer child health-related quality of life, more behavior problems, and higher rates of attention-deficit/hyperactivity disorder. Difficulty going to sleep and morning tiredness had greater adverse associations than snoring or night waking.CONCLUSIONS. Given that sleep problems are very common, the adverse outcomes shown here could affect the transition to school for a very large number of preschoolers.
Photodegradation of multilayer films based on PET copolymers
Authors: Fechine G. J. M. , Souto‐Maior R. M. , Rabello M. S. 
Published: January 2007

AbstractAn investigation was conducted on the effects of photodegradation of multilayer films based on PET copolymers. The films were composed by different layers with PET, PET/PEN, and PET/PEI copolymers with a total thickness of 23 μm. The films produced by coextrusion followed by a biaxial orientation in an industrial equipment were exposed to the ultraviolet radiation in the laboratory for periods of up to 600 h. The samples were investigated by FTIR‐ATR, UV/visible spectroscopy, fluorescence spectroscopy, size exclusion chromatography, mechanical properties, and scanning electron microscopy. The results showed that the photooxidation is concentrated at the surface layers and that coextruded films were more sensitive to the UV radiation effects. The deterioration in mechanical properties with exposure and the fracture behavior were shown to be consistent with the amount of degradation that occurred in the films. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Miscibility and rheological properties of poly(vinyl chloride)/styrene–acrylonitrile blends prepared by melt extrusion
Authors: Moon Hyun Sik , Choi Won Mook , Kim Mun Ho , Park O‐Ok 
Published: January 2007

AbstractStyrene–acrylonitrile (SAN) with acrylonitrile (AN) concentrations of 11.6–26 wt % and α‐methylstyrene acrylonitrile (αMSAN) with a wide range of AN concentrations are miscible with poly(vinyl chloride) (PVC) through solution blending. Here we examine the rheological properties and miscibility of PVC/SAN and PVC/αMSAN blends prepared by melt extrusion for commercial applications. We have investigated the rheological properties of the blends with a rheometer and a melt indexer. The PVC/SAN and PVC/αMSAN blends have a low melting torque, a long degradation time, and a high melt index, and this means that they have better processability than pure PVC. The miscibility of the blends has been characterized with differential scanning calorimetry, dynamic mechanical thermal analysis, and advanced rheometrics expansion system analysis. The miscibility of the blends has also been characterized with scanning electron microscopy. The SAN series with AN concentrations of 24–31 wt % is immiscible with PVC by melt extrusion, whereas αMSAN with 31 wt % AN is miscible with PVC, even when they are blended by melt extrusion, because of the strong interaction between PVC and αMSAN. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Applicability of a Miniaturized Micro‐Separator/Classifier to Oil‐Water Separation
Authors: Ookawara S. , Ishikawa T. , Ogawa K. 
Published: January 2007

AbstractThe micro‐separator/classifier is miniaturized to approximately 1/2 size of the original device to examine its applicability to oil‐water separation. A small amount of oil with density of 930 kg/m3 is dispersed in water. The emulsion is fed into the curved microchannels and is discharged from the inner and outer branches that form the bifurcations. The lighter oil phase is collected from the outer branch. A possibility of simultaneous separation of heavier and lighter phases is brought about by the principle of lift‐force induced separation. The cut‐size and pressure loss are much smaller than those of existing hydrocyclones. Further, the miniaturized device attains smaller cut‐size compared with the larger original device applied to solid separation with larger density difference. The suitability of the device to numbering‐up methodology is argued based on the fact that the cut‐size is insensitive to total flow‐rate.
Investigation of the Mechanism of Action of Pyrogallol–Phloroglucinol Transhydroxylase by Using Putative Intermediates
Authors: Paizs Csaba , Bartlewski‐Hof Ulrike , Rétey János 
Published: January 2007

AbstractPyrogallol–phloroglucinol transhydroxylase from Pelobacter acidigallici, a molybdopterin‐containing enzyme, catalyzes a key reaction in the anaerobic degradation of aromatic compounds. In vitro, the enzymatic reaction requires 1,2,3,5‐tetrahydroxybenzene as a cocatalyst and the transhydroxylation occurs without exchange with hydroxy groups from water. To test our previous proposal that the transfer of the hydroxy group occurs via 2,4,6,3′,4′,5′‐hexahydroxydiphenyl ether as an intermediate, we synthesized this compound and investigated its properties. We also describe the synthesis and characterization of 3,4,5,3′,4′,5′‐hexahydroxydiphenyl ether. Both compounds could substitute for the cocatalyst in vitro. This indicates that the diphenyl ethers can intrude into the active site and initiate the catalytic cycle. Recently, the X‐ray crystal structure of the transhydroxylase (TH) was published16 and it supports the proposed mechanism of hydroxy‐group transfer.
Annelation of Benzimidazoles with α,β‐Acetylenic γ‐Hydroxyacid Nitriles and Hydrolytic Rearrangement of the Cycloadducts on Alumina
Authors: Trofimov Boris A. , Andriyankova Ludmila V. , Mal'kina Anastasiya G. , Belyaeva Kseniya V. , Nikitina Lina P. , Dyachenko Oleg A. , Kazheva Olga N. , Chekhlov Anatolii N. , Shilov Gennadii V. , Afonin Andrei V. , Ushakov Igor' A. , Baikalova Ludmila V. 
Published: January 2007

Abstract1‐Substituted benzimidazoles are readily annelated regio‐ and stereoselectively with α,β‐acetylenic γ‐hydroxyacidnitriles under mild conditions (20–25 °C, no catalyst, no solvent) to form new polyfunctional condensed systems, 4‐cyanomethylene‐1,3‐oxazolobenzimidazoles (30–88 % yield). Unexpectedly, the latter, when chromatographed on neutral Al2O3 at room temperature, undergo a complex multi‐position hydrolytic rearrangement involving the cleavage of the imidazole ring to aminophenyl N‐substituted formamides with an aminodihydrofuran moiety in the aminophenylsubstituent, N‐(2‐{[5‐amino‐2,2‐dialkyl‐3(2H)‐furanylidene]amino}phenyl)‐N‐substituted formamides, a novel class of highly functionalized pharmacophoric compounds. The results contribute to the basic benzimidazole chemistry and provide for prospective families of drug candidates.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Cover Picture: Crystal Structures of Conformationally Locked Cyclitols: An Analysis of Hydrogen‐Bonded Architectures and their Implications in Crystal Engineering (Eur. J. Org. Chem. 3/2007)
Authors: Mehta Goverdhan , Sen Saikat , Ramesh Senaiar S. 
Published: January 2007

AbstractThe cover picture shows schematically, the manner in which a conformationally locked polycyclitol can be thought of as a LEGO® brick in the supramolecular world. This analogy manifests during the self‐assembling process by involvement of intermolecular H‐bond donors and acceptors engendered in preordained positions through the rigid trans‐decalin framework and intramolecular O–H···O hydrogen bonding between the 1,3‐diaxial OH groups. Details are discussed in the article by G. Mehta et al. on p. 423 ff.
Poly(Arylene Ether)s with Sulfonic Acid Groups on the Backbone and Pendant for Proton Exchange Membranes Used in PEMFC Applications
Authors: Tian S. H. , Shu D. , Wang S. J. , Xiao M. , Meng Y. Z. 
Published: January 2007

AbstractSulfonated poly(aryl ether) (SPAE) and sulfonated poly(fluorenyl ether ketone) (SPFEK) are synthesized by post‐sulfonation and direct polymerization from the sulfonated monomer, respectively. Flexible and smooth proton exchange membranes (PEM) are readily obtained from both polymers, by casting from their 5% solution in N, N′‐dimethylacetamide (DMAC) at 60 °C. The thermal stability, mechanical strength, and single cell performance of the as‐prepared SPAE and SPFEK membranes in a PEM fuel cell (PEMFC) are investigated. The SPAE membrane shows a water uptake of 45% at 80 °C and a proton conductivity of 1.02 × 10–2�S cm–1, which is close to that of Nafion® 115, whereas the SPFEK membrane shows a water uptake of 49% at 80 °C and a proton conductivity of 5.37 × 10–3�S cm–1. These membranes exhibit a higher mechanical strength, and very good hydrolytic and oxidative stabilities because of their specially designed molecular structures. A single cell evaluation experiment demonstrates the superior cell performance of SPAE compared to that of SPFEK and Nafion® 115. These polymers may be a promising proton membrane material for PEM fuel cell applications.
A density‐dependent elastoplastic hydro‐mechanical model for unsaturated compacted soils
Authors: Sun D. A. , Sheng D. C. , Cui H. B. , Sloan S. W. 
Published: January 2007

AbstractThis paper presents a three‐dimensional elastoplastic constitutive model for predicting the hydraulic and mechanical behaviour of unsaturated soils. It is based on experimental results obtained from a series of controlled‐suction triaxial tests on unsaturated compacted clay with different initial densities. Hydraulic hysteresis in the water‐retention behaviour is modelled as an elastoplastic process, with the elastic part modelled by a series of scanning curves and the elastoplastic part modelled by the main drying and wetting curves. The effect of void ratio on the water‐retention behaviour is studied using data obtained from controlled‐suction wetting–drying cyclic tests on unsaturated compacted clay with different initial densities. The effect of the degree of saturation on the stress–strain‐strength behaviour and the effect of void ratio on the water‐retention behaviour are considered in the model, as is the effect of suction on the hydraulic and mechanical behaviour. The initial density dependency of the compacted soil behaviour is modelled by experimental relationships between the initial density and the corresponding yield stress and, thereby, between the initial density and the normal compression line. The model is generalized to three‐dimensional stress states by assuming that the shapes of the failure and yield surfaces in the deviatoric stress plane are given by the Matsuoka–Nakai criterion. Model predictions of the stress–strain and water‐retention behaviour are compared with those obtained from triaxial tests with different initial densities under isotropic compression, triaxial compression and triaxial extension, with or without variation in suction. The comparisons indicate that the model accurately predicts the hydraulic and mechanical behaviour of unsaturated compacted soils with different initial densities using the same material constant. Copyright © 2006 John Wiley & Sons, Ltd.
Trends in antidepressant overdoses
Authors: McKenzie Mary S. , McFarland Bentson H. 
Published: January 2007

AbstractBackgroundDebate continues about antidepressants and suicide. However, there are few recent nation‐wide data about antidepressant overdoses. The purpose of this study was to describe United States trends from 1983 through 2003 in antidepressant overdoses as well as trends in health care utilization and mortality.MethodsData were obtained from the American Association of Poison Control Centers' (AAPPC) Toxic Exposure Surveillance System (TESS), the National Hospital Ambulatory Medical Care Survey (NHAMCS) of emergency departments, and the National Hospital Discharge Survey(NHDS).ResultsAntidepressant overdose reports rose dramatically in the United States (from 0.61 per 10 000 population in 1983 to 3.26 per 10 000 population in 2003) chiefly due to the rise in selective serotonin reuptake inhibitor (SSRI) ingestion. However, fatalities per antidepressant overdose report declined from 73 per 10 000 reported ingestions to 32 per 10 000 ingestions. Tricyclic antidepressant (TCA) overdoses had higher rates of hospitalization (78.7 vs. 64.7% hospitalized) and much higher fatality rates than did SSRI overdose reports (0.73 vs. 0.14% mortality). If the 55 977 SSRI overdoses in 2003 had represented TCA overdoses, then (other things being equal) approximately 410 fatalities would have been expected but only 106 people died. Emergency department visits associated with antidepressant overdose increased along with all emergency department visits. Hospitalization associated with antidepressant overdose increased in the early 1980s but then reached a plateau while overall hospitalizations declined.ConclusionsThe dramatic rise in United States antidepressant overdoses has not been reflected in antidepressant overdose fatalities nor in hospitalizations. If the marked increase in antidepressant overdoses in the United States had involved TCAs rather than SSRIs, then there would have been roughly 300 excess deaths annually. Copyright © 2007 John Wiley & Sons, Ltd.
Time‐resolved optically‐detected magnetic resonance of II–VI diluted‐magnetic‐semiconductor heterostructures
Authors: Ivanov V. Yu. , Godlewski M. , Yakovlev D. R. , Ryabchenko S. M. , Karczewski G. , Waag A. 
Published: January 2007

AbstractTime‐resolved optically‐detected magnetic resonance (ODMR) technique was used to study spin dynamics of Mn2+ ions in (Zn,Mn)Se‐ and (Cd,Mn)Te‐based diluted magnetic semiconductor quantum wells. Times of spin–lattice relaxation have been measured directly from a dynamical shift of exciton luminescence lines after a pulsed impact of 60 GHz microwave radiation. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Proton radiation effects in nitride lasers and light emitting diodes
Authors: Gonda Shun‐ichi , Tsutsumi Hiroyuki , Ito Yoshiumi , Mukai Takashi , Nagahama Shin‐ichi 
Published: January 2007

AbstractNitride laser diodes and light emitting diodes were irradiated with 200‐, 80‐ and 10‐MeV protons. The threshold current of violet laser diodes increased with increasing proton fluence to 1 × 1014 p/cm2. The increase in threshold current is considerably small compared with that of AlGaAs laser diodes. Proton energy dependence of the change of threshold current was a little bit different from that of GaN NIEL. Oscillation wavelength did not change before and after irradiation. The defect levels made by proton irradiation do not seem to be radiative recombination centers. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Correlation between optical and structural properties of (Al,Ga)N layers grown by MOCVD
Authors: Jahn Uwe , Jiang De‐Sheng , Ploog Klaus H. , Wang Xiaolan , Zhao Degang , Yang Hui 
Published: January 2007

AbstractFor both, (Al,Ga)N with low Al content grown on a GaN nucleation layer and (Al,Ga)N with high Al content gown on an AlN nucleation layer, the inhomogeneous distribution of the luminescence is linked to the distribution of defects, which may be due to inversion domains. In the former system, defect regions exhibit a much lower Al content than the nominal one leading to a splitting of the respective luminescence spectra. In the latter system, a domain‐like growth is observed with a pyramidal surface morphology and non‐radiative recombination within the domain boundaries. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A global observer for autonomous systems with bounded trajectories
Authors: Lei Hao , Wei Jianfeng , Lin Wei 
Published: January 2007

AbstractThe problem of global observer design for autonomous systems is investigated in this paper. A constructive approach is presented for the explicit design of global observers for completely observable systems whose solution trajectories are bounded from any initial condition. Since the bound of a solution trajectory depends on the initial condition and is thereforenot known a priori, the idea of universal control is employed to tune the observer gains on‐line, achieving global asymptotic convergence of the proposed high‐gain observer. Copyright © 2007 John Wiley & Sons, Ltd.