bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bubble‐based stabilization for the Helmholtz equation
Authors: Harari Isaac , Gosteev Kirill 
Published: November 2006

AbstractA comparison of two bubble‐enriched methods, derived by different considerations, indicates that the methods are identical in some cases. Thus, series representations of auxiliary functions, derived independently for the two methods, turn out to be equivalent prior to truncation. Three such series for time‐harmonic acoustics are considered. Dispersion analysis points to the more efficient series representation and provides guidelines for the number of terms to be retained. Numerical tests confirm the validity of these practical guidelines. Copyright © 2006 John Wiley & Sons, Ltd.
Multiple glass transitions and local composition effects on polymer solvent mixtures
Authors: Lipson Jane E. G. , Milner Scott T. 
Published: November 2006

AbstractRecent differential scanning calorimetry (DSC) results on polystyrene–solvent mixtures show two distinct glass transitions whose positions and widths vary with composition. Parallel work on the dynamic response in polymer blends has focused on how segmental mobilities are controlled by local composition variations within a “cooperative volume” containing the segment. Such variations arise from both chain connectivity and composition fluctuations. We account for both using a lattice model for polymer–solvent mixtures that yields the composition distribution around polymer and solvent segments. Insights from our lattice model lead us to simplified calculations of the mean and variance of local composition, both in good agreement with lattice results. Applying our model to compute DSC traces leads to an estimate of the cooperative volume, since a larger cooperative volume both reduces the biasing effect of connectivity, and narrows the composition distribution. Comparing our results to data, we are able to account for the composition‐dependent broadening with a cooperative length scale of about 2.5 nm. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3528–3545, 2006
Monte Carlo simulations of the crystallization of isotactic polypropylene
Authors: Chen Xiaofeng , Kumar Sanat K. , Ozisik Rahmi 
Published: November 2006

AbstractWe model the temperature dependent conformational changes and orientational and translational ordering of isotactic polypropylene melt in the vicinity of its melting temperature. We use the coarse grained second nearest neighbor lattice model, which has previously been shown to properly model the liquid state thermodynamics of this material. Equilibrium Monte Carlo (MC) simulations show the existence of two characteristic temperatures. Above T = 450 K the chains assume standard Gaussian statistics, but below this temperature we find that helix formation is thermodynamically favored even though the melt is still disordered. Both the helix length and fraction of chain monomers involved in helices increase monotonically with decreasing temperature, and below T = 385 K this material undergoes crystallization. Our results are consistent with recent simulations, which suggest that isothermal crystallization is temporally preceded by the formation of a smectic phase: we argue that the helices are long enough under these conditions to support liquid crystallinity. The crystallinity then evolves in these liquid crystalline “droplets”. Further, we can understand the recent results of de Jeu et al. who had found that isotactic polypropylene chains formed a smectic‐like phase under the action of a planar shear even at temperatures above the equilibrium melting point. In summary, these findings support the following physical picture: the unusual spinodal decomposition phenomena seen in the early stages of isothermal crystallization, which have been assigned to the formation of small liquid crystal droplets, have equilibrium signatures above the melting point where locally rigid chain sequences become thermodynamically stable. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3453–3460, 2006
NMR structure and binding studies confirm that PA4608 from Pseudomonas aeruginosa is a PilZ domain and a c‐di‐GMP binding protein
Authors: Ramelot Theresa A. , Yee Adelinda , Cort John R. , Semesi Anthony , Arrowsmith Cheryl H. , Kennedy Michael A. 
Published: November 2006

AbstractPA4608 is a 125 residue protein from Pseudomonas aeruginosa with a recent identification as a PilZ domain and putative bis‐(3′‐5′)‐cyclic dimeric guanosine monophosphate (c‐di‐GMP) adaptor protein that plays a role in bacterial second‐messenger regulated processes. The nuclear magnetic resonance (NMR) structure of PA4608 has been determined and c‐di‐GMP binding has been confirmed by NMR titration studies. The monomeric core structure of PA4608 contains a six‐stranded anti‐parallel β barrel flanked by three helices. Conserved surface residues among PA4608 homologs suggest the c‐di‐GMP binding site is at one end of the barrel and includes residues in the helices as well as in the unstructured N‐terminus. Chemical shift changes in PA4608 resonances upon titration with c‐di‐GMP confirm binding. This evidence supports the hypothesis that proteins containing PilZ domains are the long‐sought c‐di‐GMP adaptor proteins. Proteins 2007. © 2006 Wiley‐Liss, Inc.
Gastric Body Partition for Giant Perforated Peptic Ulcer in Critically Ill Elderly Patients
Authors: Shyu Jia‐Fwu , Chen Tien‐Hua , Shyr Yi‐Ming , Su Cheng‐Hsi , Wu Chew‐Wun , Lui Wing‐Yiu 
Published: November 2006

AbstractBackgroundTo prevent or minimize leakage after simple closure of giant perforated peptic ulcers in critically ill elderly patients, we conducted a clinical study using gastric body partition to prevent upstream gastric juice and food from passing through the sutured ulcer.MethodsTen critically ill elderly patients with giant (> 2.5 m) perforated peptic ulcer were included in the study of gastric body partition.ResultsThe patients’ mean age was 78.2 years and mean delay in treatment was 95.6 hours. None of the 10 patients had major complications after operation, although minor leakage of the sutured ulcer occurred in 4 patients. Only one patient presented with recurrent anastomotic ulcer and one patient died 28 days after surgery.ConclusionsGastric body partition and gastrojejunostomy, in addition to simple closure of a giant perforated peptic ulcer, could be a quick, easy, and potentially effective alternative to avoid or at least to minimize leakage of the sutured ulcer. Moreover, gastric body partition, unlike antral partition, might not necessarily increase risks of hypergastrinemia and marginal ulcer.
A Population‐Based Study of Pancreatic Trauma in Scotland
Authors: Scollay John M. , Yip Vincent S.K. , Garden O. James , Parks R.W. 
Published: November 2006

AbstractIntroductionThe aim of this population‐based study was to assess the incidence, mechanisms, management and outcome of patients who sustained pancreatic trauma in Scotland over the period 1992–2002.MethodsThe Scottish Trauma Audit Group database was searched for details of any patient with pancreatic trauma.ResultsAbout 111 of 52,676 patients (0.21%) were identified as having sustained pancreatic trauma. The male‐to‐female ratio was 3:1, with a median age of 32 years. Blunt trauma accounted for 66% of injuries. Road traffic accidents were the most common mechanism of injury (44%), followed by assaults (35%). Thirty‐four patients (31%) were haemodynamically unstable on arrival at hospital. Pancreatic trauma was associated with injuries to the chest (56%), head (30%) and extremities (30%); 73% of patients had other intra‐abdominal injuries. Of those who left the emergency department alive, at least 77% required a laparotomy. The mortality rate (46%) was directly proportional to the number of injuries sustained (P < 0.05) and was higher in patients with increasing age (P < 0.05), haemodynamic instability (P < 0.05) and blunt trauma (P < 0.05).ConclusionsPancreatic trauma is rare in Scotland but is associated with significant mortality. Outcome was worse in patients with advanced age, haemodynamic instability, blunt trauma and multiple injuries.
Hyperbaric Oxygen Therapy for Malignancy: A Review
Authors: Daruwalla Jurstine , Christophi Chris 
Published: November 2006

AbstractOne unique feature of tumors is the presence of hypoxic regions, which occur predominantly at the tumor center. Hypoxia has a major impact on various aspects of tumor cell function and proliferation. Hypoxic tumor cells are relatively insensitive to conventional therapy owing to cellular adaptations effected by the hypoxic microenvironment. Recent efforts have aimed to alter the hypoxic state and to reverse these adaptations to improve treatment outcome. One way to increase tumor oxygen tensions is by hyperbaric oxygen (HBO) therapy. HBO therapy can influence the tumor microenvironment at several levels. It can alter tumor hypoxia, a potent stimulus that drives angiogenesis. Hyperoxia as a result of HBO also produces reactive oxygen species, which can damage tumors by inducing excessive oxidative stress. This review outlines the importance of oxygen to tumors and the mechanisms by which tumors survive under hypoxic conditions. It also presents data from both experimental and clinical studies for the effect of HBO on malignancy.
Generation of magnetic fields in a positive–negative dusty plasma
Authors: SHUKLA NITIN , SHUKLA P.K. , LIU C.S. , MORFILL G.E. 
Published: November 2006

Abstract.It is shown that purely growing magnetic fields in a two-component dusty plasma can e generated due to the equilibrium drift of positive and negative dust grains. For this purpose, a linear dispersion relation has been derived by using the hydrodynamic equations for the charged dust fluids, the Maxwell equation and Faraday' law. The dispersion relation admits a purely growing instability, the growth rate of which is proportional to the equilibrium streaming speeds of positive and negative dust grains. A possible physical explanation for the instability is offered. Applications of our investigation to magnetic fields in the thin Martian environments, interplanetary spaces and dense molecular clouds are mentioned.
Clinical significance of organ‐ and non‐organ‐specific autoantibodies on the response to anti‐viral treatment of patients with chronic hepatitis C
Authors: GATSELIS N. K. , GEORGIADOU S. P. , KOUKOULIS G. K. , TASSOPOULOS N. , ZACHOU K. , LIASKOS C. , HATZAKIS A. , DALEKOS G. N. 
Published: November 2006

SummaryBackground  Development of organ‐ and non‐organ‐specific autoantibodies has been reported in hepatitis C virus patients treated with interferon‐α plus/minus ribavirin.Aims  To address whether prevalence and the titre of gastric parietal autoantibodies and non‐organ‐specific autoantibody in hepatitis C virus‐treated patients were affected by therapy, and if the development of these antibodies carries any clinical significance on the response to treatment, as few studies in adults have been strictly designed to address the above hypothesis.Methods  Samples at three time‐points (baseline, end of treatment, end of follow‐up) from 102 hepatitis C virus patients (39 sustained responders, 26 relapsers, 33 non‐responders; four lost in follow‐up) were studied for gastric parietal autoantibodies and/or non‐organ‐specific autoantibody by indirect immunofluorescence, commercial and in‐house enzyme‐linked immunosorbent assays.Results  Sustained virological and biochemical response was associated with antinuclear antibody absence (end of treatment or end of follow‐up), decrease of smooth‐muscle antibody titres during therapy and gastric parietal autoantibodies negativity at baseline. However, after multivariate analysis only antinuclear antibody positivity at the end of treatment and increase of smooth‐muscle antibody titres were associated with worst treatment response, independently of known factors of worst treatment outcome.Conclusions  We were able to demonstrate a negative correlation between the efficacy of anti‐viral treatment for hepatitis C virus and the presence of antinuclear antibody and smooth‐muscle antibody before treatment, or their increase during therapy.
Effects of gastric emptying on oral mycophenolic acid pharmacokinetics in stable renal allograft recipients
Authors: Naesens Maarten , Verbeke Kristin , Vanrenterghem Yves , Kuypers Dirk 
Published: November 2006

What is already known about this subject • Strategies that are more elaborate than measuring predose plasma concentrations are required for the therapeutic monitoring of mycophenolic acid (MPA).• Previous studies in healthy subjects and diabetes patients have suggested that MPA pharmacokinetics are influenced by gastric emptying, but this has not been demonstrated directly. What this study adds • This study has investigated the relationship between gastric emptying, measured directly (using the 14C octanoate and 13C glycine breath tests) and the steady‐state plasma concentration–time profile of MPA.• Delayed gastric emptying was associated with a longer tmax and lower Cmax, but total exposure to MPA was not affected.• The findings suggest that it could be misleading to rely fully on short‐term (<2 h) limited sampling strategies for MPA therapeutic monitoring in recipients with gastric emptying disorders, the latter occurring relatively frequently in solid organ transplantation.AimTo investigate the effect of gastric emptying on the pharmacokinetics of mycophenolic acid (MPA) in renal transplant patients.MethodsWe assessed the effect of gastric emptying on the disposition of MPA in 27 stable renal allograft recipients at 2 years after transplantation. Gastric emptying was measured by the 14C‐octanoate and 13C‐glycine breath test.ResultsDelayed gastric emptying was associated with a significantly longer MPA tmax[1.0 (0.33–2.0) h vs. 0.5 (0.33–1.0) h; mean difference 0.39 h, 95% confidence interval (CI) 0.03, 0.75; P = 0.0289] and with a significant decrease in the maximum MPA concentration after dosing [10.6 (6.5–21.3) mg l−1vs. 20.1 (10.7–28.5) mg l−1; mean difference 6.5 mg l−1, 95% CI 2.1, 10.9; P = 0.0075]. Despite the substantial effect of delayed gastric emptying rates on MPA Cmax and tmax, total dose‐interval exposure, measured by the MPA AUC0−4, was not affected by the rate of gastric emptying [20.4 (13.9–43.0) mg h−1 l−1vs. 22.4 (13.1–29.8) mg h−1 l−1].ConclusionDelayed gastric emptying was associatedwith a slower absorption of MPA, a longer time to reach peak concentrations and lower maximum concentrations. These effects should be taken into account when validating limited (<2 h) sampling strategies to estimate total MPA exposure, which could be unreliable when monitoring patients with gastric emptying disorders.
Population pharmacokinetic/pharmacodynamic (PK/PD) modelling of the hypothalamic–pituitary–gonadal axis following treatment with GnRH analogues
Authors: Tornøe Christoffer W. , Agersø Henrik , Senderovitz Thomas , Nielsen Henrik A. , Madsen Henrik , Karlsson Mats O. , Jonsson E. Niclas 
Published: November 2006

AimsTo develop a population pharmacokinetic/pharmacodynamic (PK/PD) model of the hypothalamic–pituitary–gonadal (HPG) axis describing the changes in luteinizing hormone (LH) and testosterone concentrations following treatment with the gonadotropin‐releasing hormone (GnRH) agonist triptorelin and the GnRH receptor blocker degarelix.MethodsFifty‐eight healthy subjects received single subcutaneous or intramuscular injections of 3.75 mg of triptorelin and 170 prostate cancer patients received multiple subcutaneous doses of degarelix of between 120 and 320 mg. All subjects were pooled for the population PK/PD data analysis. A systematic population PK/PD model‐building framework using stochastic differential equations was applied to the data to identify nonlinear dynamic dependencies and to deconvolve the functional feedback interactions of the HPG axis.ResultsIn our final PK/PD model of the HPG axis, the half‐life of LH was estimated to be 1.3 h and that of testosterone 7.69 h, which corresponds well with literature values. The estimated potency of LH with respect to testosterone secretion was 5.18 IU l−1, with a maximal stimulation of 77.5 times basal testosterone production. The estimated maximal triptorelin stimulation of the basal LH pool release was 1330 times above basal concentrations, with a potency of 0.047 ng ml−1. The LH pool release was decreased by a maximum of 94.2% by degarelix with an estimated potency of 1.49 ng ml−1.ConclusionsOur model of the HPG axis was able to account for the different dynamic responses observed after administration of both GnRH agonists and GnRH receptor blockers, suggesting that the model adequately characterizes the underlying physiology of the endocrine system.
Developing a mid‐range theory of patient advocacy through concept analysis
Authors: Bu Xiaoyan , Jezewski Mary Ann 
Published: November 2006

AbstractTitle. Developing a mid‐range theory of patient advocacy through concept analysisAim. The aim of this paper is to clarify and refine the concept of patient advocacy through synthesizing the advocacy literature in nursing and to establish a theoretical basis for future studies on patient advocacy in nursing.Background. Patient advocacy is an essential component of the Registered Nurse professional role. During the past 30 years, the patient advocacy role has become more important, but the concept of patient advocacy lacks a consistent definition and research into nurses’ patient advocacy roles is limited. There have been few quantitative empirical studies on patient advocacy in nursing.Method. Walker and Avant's method of concept analysis was used as a guideline in examining the concept of patient advocacy through synthesizing the advocacy literature in English (1974–2006).Findings. A mid‐range theory of patient advocacy emerges during the process of synthesizing and analysing the advocacy literature. Three core attributes of the concept of patient advocacy are identified: (1) safeguarding patients’ autonomy; (2) acting on behalf of patients; and (3) championing social justice in the provision of health care. They reflect nurses’ patient advocacy roles at both macro‐ and micro‐social levels. Antecedents of patient advocacy occur at both macro‐ and micro‐social levels and call for nurses’ advocacy roles in the healthcare system. Consequences produced by nurses’ patient advocacy behaviours are contextual. Nurses’ patient advocacy behaviours not only can positively influence the patients, other nurses and the nursing profession, but also can cause negative consequences for nurses who take action to advocate for patients.Conclusion. The proposed mid‐range theory may be useful in guiding advocacy practice in nursing and in guiding research in the advocacy area. The proposed theory needs to be furthered refined and tested in the future.
A pilot audit of weight loss in upper gastrointestinal oncology outpatients
Authors: Chate A. 
Published: November 2006

AbstractBackground  Patients with upper gastrointestinal malignancies have a high incidence of weight loss and malnutrition which has been associated with a reduced quality of life, performance status, increased risk of chemotherapy induced toxicity and decreased response to treatment.Aim  The aim of the pilot audit was to identify how many patients attending an upper gastrointestinal oncology outpatient clinic had lost weight or had nutritional problems.Method  A short questionnaire on present weight, weight loss and occurrence of symptoms was completed by 40 patients attending an upper gastrointestinal oncology outpatient clinic.Results  Nutritional screening, including weight, was not routinely carried out on all patients. Only 40% of patients had been weighed at their clinic visit and 65% self‐reported that they had lost weight. The frequency of symptoms in the weight loss group was higher than in the nonweight loss group and the incidence of nausea and dysphagia was significantly higher. Only 35% of patients had received dietary advice, but 68% of the remaining patients would have liked some.Conclusion  A significant number of patients reported weight loss and this was linked with a higher occurrence of symptoms influencing appetite and oral intake.
Energy and nutrient intake of Swiss women aged 75–87 years
Authors: Dumartheray E. Wynn , Krieg M.‐ A. , Cornuz J. , Whittamore D. R. , Lanham‐New S. A. , Burckhardt P. 
Published: November 2006

AbstractObjective  Reliable data about the nutrient intake of elderly noninstitutionalized women in Switzerland is lacking. The aim of this study was to assess the energy and nutrient intake in this specific population.Subjects  The 401 subjects were randomly selected women of mean age of 80.4 years (range 75–87) recruited from the Swiss SEMOF (Swiss Evaluation of the Methods of Measurement of Osteoporotic Fracture Risk) cohort study. A validated food frequency questionnaire (FFQ) was submitted to the 401 subjects to assess dietary intake.Results  The FFQ showed a mean daily energy intake of 1544 kcal (±447.7). Protein intake was 65.2 g (±19.9), that is 1.03 g kg−1 body weight per day. The mean daily intake for energy, fat, carbohydrate, calcium, magnesium, vitamin C, D and E were below the RNI. However, protein, phosphorus, potassium, iron and vitamin B6 were above the RNI.Conclusion  The mean nutrient intake of these free living Swiss elderly women was low compared with standards. Energy dense foods rich in carbohydrate, magnesium, calcium, vitamin D and E as well as regular sunshine exposure is recommended in order to optimise dietary intake.
Geological evaluation of climate General Circulation Models and model implications for Mesozoic cloud cover
Authors: Sellwood Bruce W. , Valdes Paul J. 
Published: November 2006

ABSTRACTGeneral Circulation Models (GCMs) are currently used to predict future global change. However, the robustness of GCMs can, and should, be evaluated by their ability to simulate past climate regimes. Their success in ‘retrodiction’ can then be assessed by reference to the testimony of the geological record. Geological evidence provides a database which can be used in the estimation of sea surface temperatures and other proxy data useful in palaeoclimatic studies. These data can then be used to refine the prescribed boundary conditions for running GCMs themselves. Results of modelling experiments confirm a generally warmer Mesozoic earth with arid tropics and convective rainfall higher over the oceans than at present. Circum‐polar wetlands are also indicated. Modelled cloudiness is also higher in the Mesozoic, contributing to greenhouse conditions and possibly influencing terrestrial biomes and marine ecosystems.
EPR microplates, a model for the Oman Ophiolite
Authors: Boudier F. , Nicolas A. , Ildefonse B. , Jousselin D. 
Published: November 2006

ABSTRACTStructural mapping in the Southern half of the Oman ophiolite has revealed a palaeoridge organization with similarities to an EPR microplate, forming in superfast spreading conditions. A NW‐trending propagator was rapidly opening in a lithosphere no more than 1 Myr older and itself created in a NE‐SW ridge system. The NW‐trending propagator, underlined by small mantle diapirs, was active or dying when detached as part of a future ophiolite. Local thrusting of the future ophiolite was also initiated very early, between 1 and 5 Myr after ridge accretion; it was accompanied by a 40° rotation within this time lapse. Such an activity supports the comparison of the Oman palaeoridge system with an oceanic microplate, and provides evidence to suggest the existence of thrusts at active microplates.