bluuebunny/crossref_metadata_2025_split huggingface dataset:
The essential spectrum of a system of singular ordinary differential operators of mixed order. Part III: A strongly singular case
Authors: Möller Manfred 
Published: July 2004

AbstractWe consider a system of ordinary differential operators of mixed order on an interval (0, r0), r0 > 0, where some of the coefficients are singular at 0. A special case has been dealt with by Kako, where the essential spectrum of an operator associated with a linearized magnetohydrodynamic equation was explicitly calculated. Generalizations of this problem have been considered by Hardt, Mennicken, Naboko and Faierman, Mennicken and Möller, where in each case some kind of regularity condition was required. The essential spectrum has been calculated explicitly in terms of the coefficient functions of the system; it is always bounded in these cases. Here we consider a class of problems for which the essential spectrum is unbounded. The essential spectrum is explicitly given as the essential spectrum in the limiting case. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cross‐national differences in proneness to scarcity effects: The moderating roles of familiarity, uncertainty avoidance, and need for cognitive closure
Authors: Jung Jae Min , Kellaris James J. 
Published: July 2004

AbstractThe scarcity effect is a powerful social‐influence principle used by marketers to increase the subjective desirability of products. This study explores cross‐national differences in proneness to the scarcity effect and attempts to explain observed differences in terms of boundary conditions. Results of a shopping simulation experiment show a positive effect of scarcity on purchase intent and a greater proneness to such among participants from a lower‐ (U.S.) versus higher‐ (France) context culture. Moreover, the scarcity effect is moderated by product familiarity, uncertainty avoidance, and need for cognitive closure. Differential familiarity levels may help explain the observed cross‐national differences. Managerial implications concern the conditions under which marketing appeals based on scarcity should be more (versus less) persuasive. © 2004 Wiley Periodicals, Inc.
Redefining functional models of basal ganglia organization: Role for the posteroventral pallidum in linguistic processing?
Authors: Whelan Brooke‐Mai , Murdoch Bruce E. , Theodoros Deborah G. , Darnell Ross , Silburn Peter , Hall Bruce 
Published: July 2004

AbstractTraditionally the basal ganglia have been implicated in motor behavior, as they are involved in both the execution of automatic actions and the modification of ongoing actions in novel contexts. Corresponding to cognition, the role of the basal ganglia has not been defined as explicitly. Relative to linguistic processes, contemporary theories of subcortical participation in language have endorsed a role for the globus pallidus internus (GPi) in the control of lexical–semantic operations. However, attempts to empirically validate these postulates have been largely limited to neuropsychological investigations of verbal fluency abilities subsequent to pallidotomy. We evaluated the impact of bilateral posteroventral pallidotomy (BPVP) on language function across a range of general and high‐level linguistic abilities, and validated/extended working theories of pallidal participation in language. Comprehensive linguistic profiles were compiled up to 1 month before and 3 months after BPVP in 6 subjects with Parkinson's disease (PD). Commensurate linguistic profiles were also gathered over a 3‐month period for a nonsurgical control cohort of 16 subjects with PD and a group of 16 non‐neurologically impaired controls (NC). Nonparametric between‐groups comparisons were conducted and reliable change indices calculated, relative to baseline/3‐month follow‐up difference scores. Group‐wise statistical comparisons between the three groups failed to reveal significant postoperative changes in language performance. Case‐by‐case data analysis relative to clinically consequential change indices revealed reliable alterations in performance across several language variables as a consequence of BPVP. These findings lend support to models of subcortical participation in language, which promote a role for the GPi in lexical–semantic manipulation mechanisms. Concomitant improvements and decrements in postoperative performance were interpreted within the context of additive and subtractive postlesional effects. Relative to parkinsonian cohorts, clinically reliable versus statistically significant changes on a case by case basis may provide the most accurate method of characterizing the way in which pathophysiologically divergent basal ganglia linguistic circuits respond to BPVP. © 2004 Movement Disorder Society
Timing of Plk1 and MPF activation during porcine oocyte maturation
Authors: Anger Martin , Klima Jiri , Kubelka Michal , Prochazka Radek , Motlik Jan , Schultz Richard M. 
Published: July 2004

AbstractA Polo‐like kinase 1 (Plk1) appears involved in an autocatalytic loop between CDC25C phosphatase and M phase promoting factor (MPF) in Xenopus oocytes and leads to activation of MPF that is required for germinal vesicle breakdown (GVBD). Although similar evidence for such a role of Plk1 in MPF activation during maturation of mammalian oocytes is absent, changes in Plk1 enzyme activity correlate with MPF activation, Plk1 co‐localizes with MPF, and microinjection of antibodies neutralizing Plk1 delays GVBD. In this study, we exploited the prolonged time required for maturation of porcine oocytes to define precisely the timing of Plk1 and MPF activation during maturation. GVBD typically occurs between 24 and 26 hr of culture in vitro and meiotic maturation is completed after 40–44‐hr culture. We find that Plk1 is activated before MPF, which is consistent with its role in activating MPF in mammalian oocytes. Mol. Reprod. Dev. 69: 11–16, 2004. © 2004 Wiley‐Liss, Inc.
Advances in understanding and treatment of immune‐mediated disorders of the peripheral nervous system
Authors: Kieseier Bernd C. , Kiefer Reinhard , Gold Ralf , Hemmer Bernhard , Willison Hugh J. , Hartung Hans‐Peter 
Published: July 2004

AbstractDuring recent years, novel insights in basic immunology and advances in biotechnology have contributed to an increased understanding of the pathogenetic mechanisms of immune‐mediated disorders of the peripheral nervous system. This increased knowledge has an impact on the management of patients with this class of disorders. Current advances are outlined and their implication for therapeutic approaches addressed. As a prototypic immune‐mediated neuropathy, special emphasis is placed on the pathogenesis and treatment of the Guillain–Barré syndrome and its variants. Moreover, neuropathies of the chronic inflammatory demyelinating, multifocal motor, and nonsystemic vasculitic types are discussed. This review summarizes recent progress with currently available therapies and—on the basis of present immunopathogenetic concepts—outlines future treatment strategies. Muscle Nerve 30: 131–136, 2004
Role of magnetic resonance neurography in brachial plexus lesions
Authors: Zhou Lan , Yousem David M. , Chaudhry Vinay 
Published: July 2004

AbstractMagnetic resonance neurography (MRN) is a relatively new imaging technique that is highly sensitive in detecting lesions in the peripheral nerves. We studied six cases of brachial plexopathies in which MRN played a pivotal role in making the correct diagnoses. All patients had clinical, nerve conduction, and electromyographic findings consistent with brachial plexus lesions. Four patients had brachial plexitis and two had multifocal demyelinating neuropathy presenting as brachial plexopathies. MRN in all patients showed edema, thickening, and T2 hyperintensities localized to the brachial plexus region. We conclude that MRN is a useful technique in evaluating patients with brachial plexus lesions, particularly in cases of brachial plexitis, where conventional magnetic resonance imaging is generally normal. Muscle Nerve 30: 305–309, 2004
Disorder resembling Guillain–Barré syndrome on initiation of statin therapy
Authors: Rajabally Yusuf A. , Varakantam Vivek , Abbott Richard J. 
Published: July 2004

AbstractWe report a disorder resembling Guillain–Barré syndrome, occurring on initiation of simvastatin, in a 58‐year‐old man, who had experienced a similar but milder episode after starting pravastatin 6 months earlier. This case suggests that acute polyradiculoneuropathy may represent a rare but serious side‐effect of statin treatment. It also raises the issue of the pathophysiology of acute neuropathy on statin exposure, with a hypersensitivity reaction resulting in an immune‐mediated process being possible instead of the hypothesized mitochondrial dysfunction in chronic cases. Muscle Nerve, 2004
A local branching heuristic for mixed‐integer programs with 2‐level variables, with an application to a telecommunication network design problem
Authors: Fischetti Matteo , Polo Carlo , Scantamburlo Massimo 
Published: July 2004

AbstractEffective heuristic solution methods for general Mixed‐Integer Programs (MIPs) are strongly required in many practical applications, and have been the subject of an intensive research effort in the recent years. Fischetti and Lodi recently proposed an exact solution technique based on the use of branching conditions expressed through (invalid) linear inequalities called local branching cuts. In the concluding remarks of their article, these authors anticipated the possibility their method be used to design a genuine MIP metaheuristic framework akin to Tabu Search (TS) or Variable Neighborhood Search (VNS), based on an external MIP solver. In the present article we introduce and analyze computationally a specific implementation of the above idea. In particular, we address MIPs with binary variables, and propose a variant of the classical VNS scheme that we call Diversification, Refining, and Tight‐refining (DRT). The new approach is intended to be of high generality, but exploits the specific structure of some MIPs where the set of binary variables partitions naturally into two levels, with the property that fixing the value of the first‐level variables produces an easier‐to‐solve (but still hard) subproblem. This is often the case, for example, in hard facility location problems arising in telecommunication network design. Our method detects automatically the presence in the MIP model of the first‐level binary variables, if any, according to simple heuristic criteria. This information is then exploited during the intensification phase of the local search, so as to explore nested solution neighborhoods defined by local branching cuts affecting the first‐ and second‐level variables in a different way. Computational results for a hard facility location problem arising in telecommunication UMTS network design are presented, with a comparison among different heuristic methods: the general‐purpose commercial ILOG‐Cplex 7.0 MIP code, the original Fischetti‐Lodi local branching heuristic scheme, the new DRT method, and (for some instances) ad hoc TS and VNS heuristics. The results show that the DRT method, though very simple to implement, provides better heuristic solutions than the alternative methods on all the instances of our test bed. © 2004 Wiley Periodicals, Inc. NETWORKS, Vol. 44(2), 61–72 2004
On the impact of the solution representation for the Internet Protocol Network Design Problem with max‐hop constraints
Authors: De Giovanni L. , Croce F. Della , Tadei R. 
Published: July 2004

AbstractThe IP (Internet Protocol) Network Design Problem can be shortly stated as follows. Given a set of nodes and a set of traffic demands, we want to determine the minimum cost capacity installation such that all the traffic is routed. Capacity is provided by means of links of a given capacity and traffic must be loaded on the network according to the OSPF‐ECM (Open Shortest Path First—Equal Commodity Multiflow) protocol, with additional constraints on the maximum number of hops. The problem is strongly NP‐Hard, and the literature proposes local search‐based heuristics that do not take into account max‐hop constraints, or assume a simplified OSPF routing. The core in a local search approach is the network loading algorithm for the evaluation of the neighbor solutions costs. It presents critical aspects concerning both computational efficiency and memory requirements. Starting from a tabu search prototype, we show how these aspects deeply impact on the design of a local search procedure, even at the logical level. We present several properties of the related network loading problem, that allow to overcome the critical issues and lead to an efficient solution evaluation. © 2004 Wiley Periodicals, Inc. NETWORKS, VoL. 44(2), 73–83 2004
Grid scheduling by on‐line rectangle packing
Authors: Caramia Massimiliano , Giordani Stefano , Iovanella Antonio 
Published: July 2004

AbstractThe Grid computing paradigm is originated from a new computing infrastructure for scientific research and cooperation, and is becoming an established technology for large‐scale resource sharing and distributed integration. Two main problems arise: how to efficiently allocate resources to tasks and, after this, how to schedule them. In this article we propose to solve the scheduling phase by means of rectangle packing algorithms. In particular, two on‐line rectangle packing algorithms are proposed with the objective of maximizing the system efficiency. A wide computational analysis is provided. The performances of the proposed algorithms are first compared with those of known algorithms on benchmark instances for rectangle packing, and then are evaluated on different Grid scheduling scenarios associated with different processing and dataset environments. © 2004 Wiley Periodicals, Inc. NETWORKS, Vol.44(2), 106–119 2004
Predictors of patient satisfaction with inpatient hospital nursing care
Authors: Larrabee June H. , Ostrow C. Lynne , Withrow Mary Lynne , Janney Michelle A. , Hobbs Gerald R. , Burant Christopher 
Published: July 2004

AbstractThe purpose of this predictive nonexperimental study was to investigate the influence of registered nurse (RN) job satisfaction, context of care, structure of care, patient‐perceived nurse caring, and patient characteristics on patient satisfaction with inpatient hospital nursing care in an academic medical center in north‐central West Virginia. Convenience samples of patients (N = 362) and RNs (N = 90) were recruited from two medical units, two surgical units, and three intensive care step‐down units. Causal modeling identified patient‐perceived nurse caring as the major predictor of patient satisfaction, with nurse/physician (RN/MD) collaboration as the only other direct predictor. Age had an indirect influence on patient satisfaction. Strategies to achieve and maintain patient satisfaction should address the enhancement of patient‐perceived nurse caring and RN/MD collaboration. © 2004 Wiley Periodicals, Inc. Res Nurs Health 27:254–268, 2004
Effectiveness of a videotape for sexual counseling after myocardial infarction
Authors: Steinke Elaine E. , Swan James H. 
Published: July 2004

AbstractA two‐group randomized clinical trial was used to test the hypothesis that patients with myocardial infarction (MI) who receive both written instructions and a videotape to view at home will have greater knowledge, better quality of life, less anxiety, greater sexual satisfaction, and will resume sexual activity more quickly than will those who receive written instructions alone. The participants, 115 patients diagnosed with an MI, were pretested in the hospital and followed at home at 1, 3, and 5 months. The intervention was an educational videotape on return to sexual activity. Significant improvements in knowledge were found for the experimental group at 1 month. The videotape intervention provides an alternative method for education to facilitate recovery post‐MI. © 2004 Wiley Periodicals, Inc. Res Nurs Health 27:269–280, 2004
Patterns and predictors of sleep pattern disturbance after cardiac surgery
Authors: Redeker Nancy S. , Ruggiero Jeanne , Hedges Christine 
Published: July 2004

AbstractThe purposes of this study were to examine changes in sleep patterns after cardiac surgery and the contributions of preoperative sleep to postoperative sleep. Seventy‐two cardiac surgery patients wore wrist actigraphs for 3 days during the preoperative period (T1) and the 1st (T2), 4th (T3), and 8th (T4) postoperative weeks. They completed the Pittsburgh Sleep Quality Index at T1, T3, and T4. Sleep was most disturbed during the 1st postoperative week and improved at T3 and T4. Overall, sleep pattern disturbance was higher at T3 and T4 than at T1. Age, gender, preoperative New York Heart Association Functional Class, and preoperative sleep variables explained 20%–50% of the variance in sleep at T2, T3, and T4. Sleep disturbance is present preoperatively and continues during the postoperative period. © 2004 Wiley Periodicals, Inc. Res Nurs Health 27:217–224, 2004
Cigarette smoking: Evidence to guide measurement
Authors: Stevens Kathleen R. , Muñoz Laura R. 
Published: July 2004

AbstractSmoking cessation programs measure outcomes in terms of abstinence from or reduction in smoking. These outcomes can be measured through self‐report by the smoker, through measurement with a biological marker of smoking, or through a combination of both. Consideration of the relative advantages of self‐report and biomarker approaches is important in the selection of measurement strategies to evaluate outcomes in smoking cessation interventions. In this article both ways of measuring smoking behavior, self‐report and biomarkers of carbon monoxide, cotinine, nicotine, thiocyanate, and alkaloids of nicotine, are explored. Measurement approaches are discussed in light of research evidence and their physiologic bases. © 2004 Wiley Periodicals, Inc. Res Nurs Health 27:281–292, 2004
Variations in sleep hygiene practices of women with and without insomnia
Authors: Cheek Rita E. , Shaver Joan L. F. , Lentz Martha J. 
Published: July 2004

AbstractSleep hygiene education is a basic component of behavioral treatment for chronic insomnia, yet the actual sleep hygiene practices of people with insomnia have not been well documented. In this descriptive secondary analysis, midlife women ages 41–55 years with either chronic insomnia (n = 92) or good sleep (n = 29) kept diaries of sleep perceptions and sleep hygiene practices during 6 nights of somnographic monitoring at home. In both groups few reported smoking cigarettes (<10%), most drank caffeine (>80%), and many averaged 30 min of exercise per day (∼50%). Very few in either group (<10%) had regular (<30 min variation) bedtimes or getting‐up times. Compared to women with good sleep, those with insomnia reported drinking less caffeine per day, being more abstinent from alcohol, and having smaller variations in day‐to‐day alcohol intake and bedtimes. Although some women with insomnia limit or refrain from caffeine and alcohol intake, many have not optimized behaviors believed to help prevent or modulate insomnia. © 2004 Wiley Periodicals, Inc. Res Nurs Health 27:225–236, 2004
Adolescents' coping with surgery for scoliosis: Effects on recovery outcomes over time
Authors: LaMontagne Lynda L. , Hepworth Joseph T. , Cohen Frances , Salisbury Michele H. 
Published: July 2004

AbstractSurgery for adolescent idiopathic scoliosis is painful and stressful and has a long and demanding recovery. The purpose of this study was to examine pre‐ and postoperative avoidant/vigilant coping and long‐term activity outcomes through 9 months postsurgery for adolescents (11–18 years, N = 113) undergoing scoliosis surgery. Generally, more vigilant copers (preoperatively and 1 month postoperatively) participated in more activities (usual, new, and social) and had higher academic performance during recovery. Several moderation effects indicated these relationships were stronger for older adolescents and those more internal in locus of control. Adolescents were more vigilant in the hospital, became more avoidant 1 month after surgery, and remained at these levels 6 months postsurgery. Understanding coping processes and individual factors is necessary to develop interventions to help adolescents cope successfully with recovery demands. © 2004 Wiley Periodicals, Inc. Res Nurs Health 27:237–253, 2004
Calculation of NMR parameters in van der Waals complexes involving organic systems and xenon
Authors: Bagno Alessandro , Saielli Giacomo 
Published: July 2004

AbstractSome of our recent results concerning the prediction of NMR parameters for van der Waals (vdW) complexes are reviewed. Through‐space coupling constants, in organic molecules stabilized by CH–π interaction, are calculated to be of the order of 0.3 Hz, therefore above the current experimental resolution. Through‐space coupling constants between hydrocarbons and xenon are also calculated to be relatively large, of the order of a few Hz at the vdW contact distance. Finally, we present some preliminary data on the dependence of the chemical shift of xenon in vdW complexes with alkyl chains. These results will serve as a tool in molecular dynamics simulations of xenon dissolved in membranes. Copyright © 2004 John Wiley & Sons, Ltd.
Restricted rotation/tautomeric equilibrium and determination of the site and extent of protonation in bi‐imidazole nucleosides by multinuclear NMR and GIAO‐DFT calculations
Authors: Mäki Jukka , Tähtinen Petri , Kronberg Leif , Klika Karel D. 
Published: July 2004

AbstractThe restricted rotation about the conjoining bond in a series of 4″‐substituted bi‐imidazole nucleosides {5‐amino‐4‐[4″‐R‐imidazol‐2″‐yl]‐1‐(β‐d‐ribofuranosyl)‐1H‐imidazole; where R=H, methyl, hydroxymethyl, oxalo, formyl} due to intramolecular hydrogen bonding between N‐3″ and the N‐6 protons concomitant with prototropic tautomerism has been examined using multinuclear (1H, 13C and 15N) experimental NMR. Substitution at the 4″ position causes the interconversion, whilst still an intramolecular process, to yield complex spectra as the dynamic process consists of a two‐site exchange between non‐degenerate tautomeric forms (asymmetric sites). The preferred tautomers were identified experimentally in each case and compared with theoretically determined structures geometry optimized using density functional theory (DFT) at the B3LYP/6–31G(d,p) level of theory on which gauge‐independent atomic orbital‐DFT (GIAO‐DFT) computations at the B3LYP/cc‐pVTZ level of theory were applied to calculate the chemical shifts of the 1H, 13C and 15N nuclei. Both the site and the extent of protonation of the bi‐imidazole nucleosides were also similarly ascertained using the same methodology. Protonation at the pyridine‐type nitrogen (N‐3″) of the outer imidazole ring, the principle site of protonation, effectively eliminated the barrier to rotation about the conjoining bond yielding time‐averaged spectra experimentally. Copyright © 2004 John Wiley & Sons, Ltd.