bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proton MR spectroscopic imaging of rhesus macaque brain in vivo at 7T
Authors: Gonen Oded , Liu Songtao , Goelman Gadi , Ratai Eva‐Maria , Pilkenton Sarah , Lentz Margaret R. , González R. Gilberto 
Published: February 2008

AbstractDue to the overall similarity of their brains' structure and physiology to its human counterpart, nonhuman primates provide excellent model systems for the pathogenesis of neurological diseases and their response to treatments. Its much smaller size, 80 versus 1250 cm3, however, requires proportionally higher spatial resolution to study, nondestructively, as many analogous regions as efficiently as possible in anesthetized animals. The confluence of these requirements underscores the need for the highest sensitivity, spatial coverage, resolution, and exam speed. Accordingly, we demonstrate the feasibility of 3D multi‐voxel, proton (1H) MRSI at (0.375 cm)3 = 0.05 cm3 isotropic spatial resolution over 21 cm3 (≈25%) of the anesthetized rhesus macaques brain at 7T in 25 min. These voxels are ×102–101 times smaller than the 8–1 cm3 common to 1H‐MRS in humans, retaining similar proportions between the macaque and human brain. The spectra showed a signal‐to‐noise‐ratio (SNR) ≈9–10 for the major metabolites and the interanimal SNR spatial distribution reproducibility was in the ±10% range for the standard error of their means (SEMs). Their metabolites' linewidths, 9 ± 2 Hz, yield excellent spectral resolution as well. These results indicate that 3D 1H‐MRSI can be integrated into comprehensive MR studies in primates at such high fields. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
Shortest path network interdiction with asymmetric information
Authors: Bayrak Halil , Bailey Matthew D. 
Published: February 2008

AbstractWe consider an extension of the shortest path network interdiction problem. In this problem an evader attempts to minimize the length of the shortest path between the origin and the destination in a network, while an interdictor attempts to maximize the length of this shortest path by interdicting network arcs using limited resources. We consider the case where there is asymmetric information, i.e., the evader and the interdictor have different levels of information about the network. We formulate this problem as a nonlinear mixed integer program and show that this formulation can be converted to a linear mixed integer program. Computational results demonstrate improvements in the objective function values over the shortest path network interdiction problem with symmetric information. © 2008 Wiley Periodicals, Inc. NETWORKS, 2008
Minimizing a stochastic maximum‐reliability path
Authors: Pan Feng , Morton David P. 
Published: February 2008

AbstractWe consider a stochastic network interdiction problem in which the goal is to detect an evader, who selects a maximum‐reliability path. Subject to a resource constraint, the interdictor installs sensors on a subset of the network's arcs to minimize the value of the evader's maximum‐reliability path, i.e., to maximize the detection probability. When this decision is made, the evader's origin–destination pair is known to the interdictor only through a probability distribution. Our model is framed as a stochastic mixed‐integer program and solved by an enhanced L‐shaped decomposition method. Our primary enhancement is via a valid inequality, which we call a step inequality. In earlier work [Morton et al., IIE Trans 39 (2007), 3–14], we developed step inequalities for the special case in which the evader encounters at most one sensor on an origin–destination path. Here, we generalize the step inequality to the case where the evader encounters multiple sensors. In this more general setting, the step inequality is tightly coupled to the decomposition scheme. An efficient separation algorithm identifies violated step inequalities and strengthens the linear programming relaxation of the L‐shaped method's master program. We apply this solution procedure with further computational enhancements to a collection of test problems. © 2008 Wiley Periodicals, Inc. NETWORKS, 2008
Price competition with elastic traffic
Authors: Ozdaglar Asuman 
Published: February 2008

AbstractIn this paper, we present a combined study of price competition and traffic control in a congested network. We study a model in which service providers own the routes in a network and set prices to maximize their profits, while users choose the amount of flow to send and the routing of the flow according to Wardrop's principle. When utility functions of users are concave and have concave first derivatives, we characterize a tight bound of 2/3 on efficiency in pure strategy equilibria of the price competition game. We obtain the same bound under the assumption that there is no fixed latency cost, i.e., the latency of a link at zero flow is equal to zero. These bounds are tight even when the numbers of routes and service providers are arbitrarily large. © 2008 Wiley Periodicals, Inc. NETWORKS, 2008
Network search games, with arbitrary searcher starting point
Authors: Dagan Arnon , Gal Shmuel 
Published: February 2008

AbstractWe analyze a zero‐sum game between a blind unit‐speed searcher and a stationary hider on a given network Q, where the payoff is the time for the searcher to reach the hider. In contrast to the standard game studied in the literature, we do not assume that the searcher has to start from a fixed point (known to the hider) but can choose his starting point. We show that for some networks, including trees, the optimal searcher, and hider strategies have a simple structure. © 2008 Wiley Periodicals, Inc. NETWORKS, 2008
A linear programming approach to increasing the weight of all minimum spanning trees
Authors: Baïou Mourad , Barahona Francisco 
Published: February 2008

AbstractGiven a graph where increasing the weight of an edge has a nondecreasing convex piecewise linear cost, we study the problem of finding a minimum cost increase of the weights so that the value of all minimum spanning trees is equal to some target value. Frederickson and Solis‐Oba gave an algorithm for the case when the costs are linear. We give a different derivation of their algorithm, and we slightly extend it to deal with convex piecewise linear costs. We formulate the problem as a combinatorial linear program and show how to produce primal and dual solutions. © 2008 Wiley Periodicals, Inc. NETWORKS, 2008
An iterative regularization method in estimating the unknown energy source by laser pulses with a dual‐phase‐lag model
Authors: Huang Cheng‐Hung , Lin Chien‐Yu 
Published: February 2008

AbstractIn the present study an inverse problem for hyperbolic heat conduction with a dual‐phase‐lag model is solved by the conjugate gradient method (CGM) in estimating the unknown heat generation, due to the ultra‐short duration laser heating, based on the interior temperature measurements. Results obtained in this inverse problem will be justified based on the numerical experiments where two different heat source distributions are to be estimated. Results show that the inverse solutions can always be obtained when choosing the initial guesses of the heat sources equal to zero. Finally, it is concluded that accurate heat sources can be estimated in this study. Copyright © 2008 John Wiley & Sons, Ltd.
Pulmonary nodules discovered during the initial evaluation of pediatric patients with bone and soft‐tissue sarcoma
Authors: Absalon Michael J. , McCarville M. Beth , Liu Tiebin , Santana Victor M. , Daw Najat C. , Navid Fariba 
Published: February 2008

AbstractBackgroundRecent technical advances in CT imaging and data processing have improved the ability to detect small pulmonary nodules in children with bone and soft‐tissue sarcoma undergoing radiologic imaging of the chest.ProcedureWe retrospectively studied medical records and CT chest scans at initial diagnosis of 210 children and young adults presenting to a single pediatric tertiary care hospital specialized in oncology for evaluation of bone or soft‐tissue sarcoma. We correlated clinical features and CT scan findings with patient outcome and histologic results, when available.ResultsPulmonary nodules (diameter ≤3 cm) were identified in 66 patients (31.4%). The median size of the largest nodule in each patient was 5 mm (range, 1–20 mm). Of patients who underwent biopsy or resection of a nodule, 41.7% had metastatic pulmonary disease. Having more than three nodules and a bilateral distribution were associated with histology‐proven metastasis (P = 0.002 and P = 0.011, respectively) and an increased frequency of recurrent or progressive metastatic disease in the lung (P < 0.001 and P = 0.023, respectively). Greater size of the largest nodule present showed a trend towards biopsy‐proven lung metastasis, but did not reach statistical significance (P = 0.06). When biopsy or resection was not performed, increased size was significantly associated with nodules being presumed as malignant (median, 16.8 mm compared to 4.0 mm for biopsied nodules, P < 0.001).ConclusionsPulmonary nodules were commonly detected during the initial evaluation of pediatric cases of sarcoma. Number and distribution of nodules were significantly associated with metastatic disease and outcome. Pediatr Blood Cancer 2008;50:1147–1153. © 2008 Wiley‐Liss, Inc.
Team management, twinning, and telemedicine in retinoblastoma: A 3‐tier approach implemented in the first eye salvage program in Jordan
Authors: Qaddoumi Ibrahim , Nawaiseh Ibrahim , Mehyar Mustafa , Razzouk Bassem , Haik Barrett G. , Kharma Saamir , Jaradat Imad , Rodriguez‐Galindo Carlos , Wilson Matthew W. 
Published: February 2008

AbstractBackgroundThis study evaluated the outcome of retinoblastoma patients, when employing a telemedicine‐based twinning program in Jordan.ProcedureThis cohort study included patients at the King Hussein Cancer Centre (KHCC; Amman, Jordan) who received consultations for retinoblastoma from March 2003 to September 2006. A collaborative program was established with the International Outreach Program at St. Jude Children's Research Hospital in Memphis, Tennessee. Cases were discussed using an Internet consultation service where fundus images, clinical history, and proposed treatment were reviewed. Selected cases were further discussed via videoconferencing and electronic mail.ResultsThirty‐three children with retinoblastoma (20 bilateral) were treated at KHCC. The median age at diagnosis was 7 months for patients with bilateral retinoblastoma and 35 months for patients with unilateral retinoblastoma. Of the 20 patients with bilateral disease, 12 were newly diagnosed and 8 had received prior treatment. Our success in the bilateral cases was most evident in the previously untreated group, in which only six eyes (25%) were enucleated and four eyes (17%) were irradiated. Of the 13 patients with unilateral retinoblastoma, 12 underwent enucleation, and 6 required radiation. Neither group experienced mortality.ConclusionsTwinning has positively impacted survival and ocular salvage in Jordan. By partnering a team of professionals with mentors willing to provide close supervision, the highly specialized management of retinoblastoma can be successfully implemented in a developing country. Pediatr Blood Cancer 2008;51:241–244. © 2006 Wiley‐Liss, Inc.
Day hospital versus inpatient management of uncomplicated vaso‐occlusive crises in children with sickle cell disease
Authors: Raphael Jean L. , Kamdar Aditi , Wang Tao , Liu Hao , Mahoney Donald H. , Mueller Brigitta U. 
Published: February 2008

AbstractBackgroundDay hospital (DH) management for patients with sickle cell disease (SCD) experiencing uncomplicated vaso‐occlusive pain crises has been utilized as an alternative care delivery system to inpatient hospitalization. The objective of this study was to determine whether DH management results in shorter length of stay compared to inpatient care.ProcedureWe conducted a retrospective cohort study with 35 DH admissions and 35 inpatient admissions for children with SCD presenting with uncomplicated vaso‐occlusive crises (VOCs). A DH admission was defined as a minimum of two consecutive days of aggressive pain management as an outpatient, including intravenous hydration and analgesics, supported by home treatment over night with oral analgesic and anti‐inflammatory agents. We gathered data on demographics, pain scores, length of stay, admission charges, and needs for persistent care.ResultsDH care resulted in a 39% reduction of the average length of stay compared to inpatient admissions. Multivariate linear regression demonstrated that the location of patient care for VOCs was a significant predictor of length of stay (P < 0.0006) after controlling for patient characteristics, severity of illness, and disease history.ConclusionsWe conclude that a dedicated DH facility has the potential to provide efficient and timely management of uncomplicated VOCs through reduction of length of stay. This delivery care system may be particularly relevant for children who are significantly impacted by inpatient hospitalization. Pediatr Blood Cancer 2008;51:398–401. © 2008 Wiley‐Liss, Inc.
Metachronous manifestations of sweet's syndrome in a neutropenic patient with Fanconi anemia
Authors: Chatham‐Stephens Kevin , Devere Theresa , Guzman‐Cottrill Judith , Kurre Peter 
Published: February 2008

AbstractSweet's syndrome (SS) is an acute, febrile neutrophilic dermatosis that frequently presents with leukocytosis and erythematous plaques. Lesions show neutrophilic infiltration of the dermis and rarely other organs. We report the case of an adolescent male with chronic pancytopenia secondary to Fanconi anemia (FA) who presented with acute respiratory distress. Despite an exhaustive and ultimately unrevealing work‐up, the diagnosis of pulmonary SS was not made until he developed characteristic cutaneous lesions 4 months later. Comprehensive review of pathological specimens revealed metachronous SS manifestations with infiltrates in lung parenchyma, dermis, and subcutis in this neutropenic patient. Pediatr Blood Cancer 2008;51:128–130. © 2008 Wiley‐Liss, Inc.
The use of questionnaires for measuring patient‐reported side effects of drugs: its importance and methodological challenges
Authors: Foster PhD Juliet M. , van der Molen MD, PhD Thys , Caeser PhD Manfred , Hannaford MD, PhD Philip 
Published: February 2008

AbstractPatient‐reported outcomes such as Quality of Life often play an important part in the efficacy assessment of drug treatment. Although instruments that measure quality of life can detect the positive effects of treatments on health status, they may not measure the effect of negative treatment‐related symptoms. Patients often fail to spontaneously report common or clinically mild drug‐related symptoms, even though the same symptoms can result in the stopping or skipping of prescribed doses. Therefore, as with quality of life assessments, the perception of patients on possible side effects of treatments is best captured by the use of self‐report questionnaires. There are substantial challenges with creating well‐validated, relevant questionnaires that capture the full range of patient‐reported symptoms and signs. A review of 13 existing instruments showed that many patient‐rated side effect questionnaires had been developed, often to a high standard, using well‐established psychometric methods. However, there were some inconsistencies in the methods used by the questionnaire developers, indicating the need for standardisation when creating new, or adapting previous, instruments. Even with their current deficits, it is important that patient‐reported side effect questionnaires be used more in drug development, health outcomes research and resource allocation; all with the ultimate aim of improving quality of patient care. Copyright © 2008 John Wiley & Sons, Ltd.
Determination of different morphological structures in PC/ABS open spiral injection moldings
Authors: O‐Charoen N. , Leong Y.W. , Hamada H. 
Published: February 2008

AbstractThe internal structure of injection molded polymer blends are complex and greatly affect the mechanical properties. In this work, the microstructure development was observed for a Polycarbonate (PC)/Acrylonitrile‐Butadiene‐Styrene (ABS) blend (60/40 wt% blend ratio) that was injection molded using an open spiral mold. The ABS‐rich phase was chemically etched out, leaving behind cavities of different shapes and sizes. With increasing depth, different morphological structures were observed due to the variation of temperature and shear profiles. The changes in morphology can be abrupt, especially at the regions closest to the external surface of the specimen, while a more gradual transition was observed with increasing specimen depth. Thus, a methodology is developed to segregate these structures into different and distinctive layers (skin, shear, intermediate, and core layers) corresponding to the state of shear flow, cavity pressure and distance from the gate. The thickness of these layers and the characteristics of the cavities (i.e. shapes and sizes) are believed to have a direct impact on the final mechanical properties of the moldings. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
The mastication characteristics of powdered carbon black filled natural rubber during internal mixing
Authors: Zhang Anqiang , Lin Yaling , Wang Lianshi 
Published: February 2008

AbstractPowdered carbon black filled natural rubber, P(NR/HAF), is a premixture of natural rubber and carbon black in powdered form with good carbon black dispersion throughout the rubber matrix. In this study, the mastication properties of P(NR/HAF) were observed under a wide temperature range (50–110°C) and rotor speed (30–100 rpm) range, using a mixing head attached to Brabender Plasticorder. It was found that P(NR/HAF) showed different mastication characteristic, compared to the traditional internal mastication theories of natural rubber; poor masticating properties of P(NR/HAF) are observed with low rotor speed and high temperature and a ‘‘stable zone’’ with middle rotor speed and lower temperature. The Mooney viscosity of rubber batch under different rotor speed and temperature was almost the same, and mastication properties were unsatisfactory. It was considered that the higher temperature build‐up of the mixing batch of P(NR/HAF) during the early stage of internal mixing results in the special mastication properties. A quadratic mastication model of P(NR/HAF), based on the multivariate regression analysis and stepwise regression analysis, was used to predict the mastication characters of P(NR/HAF) in internal mixer under varied temperature and rotor speed. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
The electrical properties of boron‐containing poly(vinyl alcohol) derived ceramic organic semiconductor
Authors: Yakuphanoglu Fahrettin , Schiavon Marco Antônio 
Published: February 2008

AbstractThe direct and alternating current conductivity, space charge limited current, and thermoelectrical properties of boron‐containing poly(vinyl alcohol)‐derived ceramic have been investigated. The electrical conductivity of the sample increases with increase in temperature and the room temperature conductivity of the sample was found to be 3.82 × 10−5 S/cm. The electrical conductivity and thermoelectric power results suggest that the PVAB polymer has p‐type electrical conductivity. The current–voltage characteristics indicate that at higher voltages, the space charge limited conductivity mechanism is dominant in the PVAB sample. The electronic parameters such as the position of the Fermi level bottom of the conduction band, EF, the density of states in conduction band Nc, effective mass of holes ms were found to be 0.44 eV, 2.12 × 1025 m−3, and 0.59 mo, respectively. Alternating current conductivity results suggest that the correlated barrier hopping conductivity is dominant in AC conductivity mechanism of the sample. The imaginary part of the dielectrical modulus at different temperatures shows a relaxation peak, indicating a temperature‐dependent non‐Debye relaxation. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Synthesis and characterization of hollow polyaniline microtubes and microbelts with nanostructured walls in sodium dodecyl sulfate micellar solutions
Authors: Wu Tzong‐Ming , Lin Yen‐Wen 
Published: February 2008

AbstractDoped polyaniline in its emeraldine salt form (PANI‐ES) were successfully prepared by in situ chemical oxidative polymerization using various concentrations of sodium dodecyl sulfate (SDS) micellar solutions. Structural analysis using field‐emission scanning electron microscopy and high‐resolution transmission electron microscopy showed that the morphologies of fabricated PANI‐ES contain hollow tube‐like and belt‐like structures with thickness in the range of 100–200 nm, diameters in the range of 1–5 μm, and lengths up to several tens and hundreds of micrometers. The changes of morphology from particle‐like into microtube‐like or microbelt‐like structure with nanostructured walls are strongly dependent on the concentration of SDS. The conductivities of fabricated PANI‐ES with 0.1 M SDS content at room temperature are 80% higher than those of PANI‐ES without SDS, perhaps because SDS may serve as a dopant or the formation of one‐dimensional structure to improve the conductivity of PANI‐ES. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Thermal degradation and physical aging of poly(lactic acid) and its blends with starch
Authors: Acioli‐Moura Ricardo , Sun Xiuzhi Susan 
Published: February 2008

AbstractPoly(lactic acid) (PLA) and its blends with starch and methylenediphenyl diisocyanate (MDI) were extruded in a twin‐screw extruder and compress‐molded in a dog‐bone shaped tensile bars to form test specimens. The thermalgravimetric profile and thermal endurance of these samples were characterized. The effect of physical aging on mechanical and thermal properties of these samples was evaluated. For the aging study, samples were stored at 25°C and relative humidity fluctuating between 90 and 30%, from 2 to 180 days, with or without a polyethylene bag as a moisture barrier. Physical aging of pure PLA samples stored in a controlled environment from 2 to 360 days was also evaluated. The presence of MDI in the PLA/starch composite did not affect the thermal decomposition profile. The PLA showed the highest Arrhenius activation energy and strongest thermal endurance of all samples, followed by PLA/starch/MDI and PLA/starch. Exposure of the samples to storage conditions with fluctuating relative humidity (RH) significantly affects thermal‐mechanical performance of PLA and its composites. But, the samples stored in plastic bags can minimize such effects. Mechanical properties of PLA and PLA/starch‐based composites sealed in plastic bags had no significant change during 30‐day storage in fluctuating humidity conditions (30–90% RH). POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Der Large Hadron Collider – die Entdeckungsmaschine. Teilchenphysik
Authors: Müller Thomas 
Published: February 2008

AbstractAm Europäischen Zentrum für Teilchenphysik CERN läuft demnächst der Large Hadron Collider, LHC, an. Er soll Protonen mit einer Schwerpunktenergie bis zu 14 TeV und Blei‐Ionen bis zu 1144 TeV miteinander kollidieren lassen. Mehr als 6000 Wissenschaftler und Ingenieure aus rund 500 Instituten aus aller Welt sind am Bau der Detektoren beteiligt. Hauptziele des LHC sind die Entdeckung des Higgs‐Bosons und Teilchen der Supersymmetrie sowie die Erzeugung des Quark‐Gluon‐Plasmas. Auch Fragen nach der Dunklen Materie und kleinen Schwarzen Löchern lassen sich angehen. Der LHC soll mindestens zwanzig Jahre lang arbeiten.