bluuebunny/crossref_metadata_2025_split huggingface dataset:
Localized excitons and defects in PbWO4 single crystals: a luminescence and photo‐thermally stimulated disintegration study
Authors: Krasnikov A. , Nikl M. , Zazubovich S. 
Published: May 2006

AbstractLuminescence from the exciton‐ and defect‐related states and photo‐thermally stimulated disintegration of these states under selective UV irradiation were studied in the PbWO4:Mo, Ce crystal and compared with the characteristics of other undoped and doped PbWO4 crystals of different origin. For the first time, various localized exciton states were identified and their decay into stable defects was found. Different positions, halfwidths and temperature dependences were observed for the blue emission spectrum in different PbWO4 crystals and explained by the presence of strongly overlapping emission bands of the WO42–‐type self‐trapped and localized excitons. Binding energies of the self‐trapped and localized exciton states were calculated. The dominant thermally stimulated luminescence peaks, created in the PbWO4:Mo, Ce crystal by the UV radiation, are located at 110, 202 and 247 K. The related trap depths were calculated using the initial rise method. It was concluded that under irradiation in the exciton absorption region, defects are mainly created due to the disintegration of the localized exciton states, which occurs without release of free charge carriers. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Some Properties of Starch Isolated from Radix Cynanchi bungei
Authors: Song Zhi‐Gang , Wang Jian‐Hua , Wang Han‐Zhong , Zhao Ai‐Hong , Liu Chun‐Xiao , Tian Ji‐Chun 
Published: May 2006

AbstractThe physicochemical and scanning electron micrograph characteristics of Radix Cynanchi bungei (RCb) starch were investigated. RCb starch presented an apparent amylose content of 20.1%, less than that of potato starch (23.6%), with a granule size ranging from 5 to 15 μm with round, spherical and polygonal shapes and B‐type X‐ray diffraction pattern. The RVA pasting properties of RCb starch were similar to those of potato starch, with pasting temperature of 60.8°C, lower than that of potato starch (64.3°C). The gelatinization parameters of RCb starch were found to be 55.9°C (To), 60.0°C (Tp), 66.6°C (TC) and 13.2 J/g (ΔH) while those of potato starch were 58.9°C, 63.5°C, 68.6°C and 13.2 J/g. Both RCb and potato starch pastes behaved as high shear‐thinning liquids. RCb starch pastes had lower apparent viscosity than potato starch pastes at the same shear rate.
Pasting Properties of Non‐waxy Rice Starch‐Hydrocolloid Mixtures
Authors: Song Ji‐Young , Kwon Ji‐Young , Choi Jungdo , Kim Young‐Chang , Shin Malshick 
Published: May 2006

AbstractThe swelling and pasting properties of non‐waxy rice starch‐hydrocolloid mixtures were investigated using commercial and laboratory‐generated hydrocolloids. The swelling power of the rice starch‐hydrocolloid mixtures was generally depressed at low concentration of hydrocolloids (0–0.05%), but increased directly with increasing hydrocolloid concentrations (0.05–0.1%). In gellan gum dispersion, the swelling power at 100°C was higher than that of control. The rice starch‐hydrocolloids mixtures showed shear‐thinning flow behavior (n = 0.26–0.49). Hydrocolloids except the exopolysaccharide from S. chungbukensis (EPS‐CB) increased apparent viscosity and consistency index (K) of rice starch dispersions, but decreased the n value. Hydrocolloids enhanced the trough and final viscosity of rice starch dispersions but EPS‐CB reduced the viscosity of rice starch pastes. Hydrocolloids lowered peak viscosity but addition of guar gum resulted in high peak viscosity, apparent viscosity, and consistency index of rice starch dispersions. Total setback viscosity appeared to be not affected by hydrocolloids at low concentration (0.05%). The hot and cold paste of the starch‐gellan gum mixture exhibited the highest viscosity values in the Brookfield viscometer.
Placental volume measured by three‐dimensional ultrasound in the prediction of fetal α0‐thalassemia: a preliminary report
Authors: Chen M. , Leung K. Y. , Lee C. P. , Tang M. H. Y. , Ho P. C. 
Published: May 2006

AbstractObjectiveTo evaluate the use of placental volume measured by three‐dimensional (3D) ultrasound in predicting fetal homozygous α0‐thalassemia (Hb‐Bart's disease).MethodsFrom June 2002 to May 2004 singleton pregnancies at risk of α0‐thalassemia and normal controls were studied prospectively at 9–12 weeks of gestation. Affected fetuses were suspected to have α0‐thalassemia by two‐dimensional (2D) ultrasound and confirmed by DNA analysis. Placental volume was measured on 3D ultrasound by a multiplanar technique. Intra‐ and interobserver agreement of measurements was assessed. The placental volume/crown–rump length quotient of the affected fetuses was compared with that of normal fetuses.ResultsThe final study group comprised 105 pregnancies; 43 were at risk of α0‐thalassemia and 62 were normal controls. Eleven (10.5%) fetuses were affected by α0‐thalassemia, all from the at‐risk group, and the others were normal. Intra‐ and interobserver agreement of volume measurement by 3D ultrasound was relatively poor; this was reflected in the wide limits of agreement, which ranged from −10.82 to 40.86 mL. The mean ± SD placental volume/crown–rump length quotient in affected pregnancies was larger than that in unaffected pregnancies (1.37 ± 0.65 vs. 1.13 ± 0.39), but this difference was not significant (P > 0.05).ConclusionsAssessment of placental volume by 3D ultrasound does not seem to be superior to 2D ultrasound in the first‐trimester prediction of α0‐thalassemia. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Crosslinking of PVC formulations treated with UV light
Authors: Arias G. , Benavides R. , Castillo Garza E.L. , Téllez Rosas M.M. 
Published: May 2006

AbstractTypical wire and cable formulations of plasticized Poly(vinyl chloride) were prepared with three different stabilizer systems: Ca/Zn (2:1 or 1:1) and dibasic lead phthalate. The mixtures contained trimethylolpropane trimethacrylate (TMPTMA) as crosslinking agent and a UV photoinitiator (Irgacure 819). Mixtures were dry‐blended, then roll‐milled and to finally hot‐pressed at 180°C to obtain sheets of 1 and 1.5 mm thickness. Small specimens (3 × 3 cm) were irradiated with UV light for up to 10 days while monitoring changes at different time intervals. The presence of TMPTMA in the samples, as expected, influenced the storage modulus (E′) and gel content percentage, specifically for the thinner samples. These results indicated that UV irradiation produced surface crosslinking. The samples with crosslinking agent also reached higher carbonyl index values. The Ca/Zn formulations showed higher mechanical properties with respect to the Pb ones, thus suggesting that during the stabilization period of the Ca/Zn mixtures, an effective crosslinking was promoted. Irregular behavior was observed during the last days of treatment for both types of formulations, thereby suggesting an optimum irradiation time for this procedure. J. VINYL. ADDIT. TECHNOL. 12:49–54, 2006. © 2006 Society of Plastics Engineers.
Effect of a N,N′‐disubstituted phenylenediamine stabilizer and SB/EPDM compatibilizer on toughness and morphology of blends of pre‐aged polyethylene with high‐impact polystyrene
Authors: Michálková D. , Pospíšil J. , Fortelný I. , Šlouf M. , Kruliš Z. 
Published: May 2006

AbstractThe effect of a N,N′‐disubstituted 1,4‐phenylenediamine stabilizer and styrene‐butadiene block copolymer (SB)/ethylene‐propylene elastomer (EPDM) compatibilizer on mechanical properties and phase structure of pre‐aged low‐density polyethylene (LDPE; a model of aged recyclate)/high‐impact polystyrene (HIPS) blends was studied. A strong cooperative effect between the stabilizer and compatibilizer on the impact strength and fineness of the phase structure of LDPE/HIPS blends was found. Analysis of chemical reactions assumed to proceed in the system during processing led to the conclusion that improvement in the impact strength and phase structure was accounted for by reactive formation of a LDPE‐SB graft copolymer in a process supported by the presence of the bifunctional amine‐based stabilizer. The mixture of the amine stabilizer with SB/EPDM is a very promising upgrading system for post‐consumer plastic waste containing pre‐oxidized LDPE. J. VINYL. ADDIT. TECHNOL. 12:58–65, 2006. © 2006 Society of Plastics Engineers.
Processing highly filled pre‐compounded pellets on single screw extruders
Authors: Steward Edward L. 
Published: May 2006

AbstractThis article discusses, in general terms, several approaches to producing highly filled plastics. Emphasis is on wood flour, with polyolefins as an example. Processing other highly filled polymer and filler choices follows the same logic. Successful approaches include the single screw machine being fed pre‐pelletized material. A large pelletizing twin screw compounder selected for compounding for its output rate isolates the complexities of the compounding step from the profile lines, which have their own unique challenges, such as sizing and cooling the part at good quality and with good tolerances. Operating a few big pelletizing twin screw machines would allow the simple single screw lines of various sizes to run at decent efficiencies on big or small profiles. Since not one machinery approach has monopolized this application to date, some of the major processing and equipment comparisons are discussed. J. VINYL. ADDIT. TECHNOL. 12:83–86, 2006. © 2006 Society of Plastics Engineers
Mobility changes anonymity: new passive threats in mobile ad hoc networks
Authors: Hong Xiaoyan , Kong Jiejun , Gerla Mario 
Published: May 2006

AbstractPrivacy in mobile ad hoc networks has new semantics in addition to the conventional notions for infrastructure networks. Mobility enabled by wireless communication has significantly changed privacy issues and anonymity research in many ways. In particular, mobility requires ad hoc routing schemes to transmit messages frequently in an open wireless medium. The routing traffic facilitates adversaries in conducting various attacks threatening the network security and privacy. In this work, we focus on passive routing attacks. We present an extensive study on new anonymity threats and classify the corresponding security demands into three new categories: (1)venue anonymity; (2)privacy of ad hoc network topology; and (3)privacy of motion pattern. These new aspects are all introduced by mobility and left unaddressed in fixed infrastructure. This leads us to investigate new design principles. Our study suggests thaton‐demand routing,identity‐free routing, andneighborhood traffic mixingare better design choices to defend against the new anonymity threats in mobile networks. The paper also demonstrates through examples on the visualization of the mobile anonymity attacks and on the quantification of the effectiveness of the attacks. Copyright © 2006 John Wiley & Sons, Ltd.
A secure incentive architecture for ad hoc networks
Authors: He Qi , Wu Dapeng , Khosla Pradeep 
Published: May 2006

AbstractIn an ad hoc network, intermediate nodes on a communication path are expected to forward packets of other nodes so that the mobile nodes can communicate beyond their wireless transmission range. However, because wireless mobile nodes are usually constrained by limited power and computation resources, a selfish node may be unwilling to spend its resources in forwarding packets which are not of its direct interest, even though it expects other nodes to forward its packets to the destination. It has been shown that the presence of such selfish nodes degrades the overall performance of a non‐cooperative ad hoc network. To address this problem, we propose a secure and objective reputation‐based incentive (SORI) architecture to encourage packet forwarding and discipline selfish behavior. Different from existing schemes, under our architecture, the reputation of a node is quantified by objective measures; the propagation of reputation is efficiently secured by a one‐way‐hash‐chain‐based authentication scheme; and secure routing is in place. Armed with the reputation‐based mechanism, we design a punishment scheme to penalize selfish nodes. The experimental results show that the proposed scheme can successfully identify selfish nodes and punish them accordingly. Copyright © 2006 John Wiley & Sons, Ltd.
DISPOSER: distributed secure position service in mobile ad hoc networks
Authors: Wu Xiaoxin 
Published: May 2006

AbstractPosition service is essential for position‐based ad hoc routing algorithms, which have proved to have decent network performance. As private information, node positions are valuable for attackers to locate their targets. Therefore, a secure position service system is needed. In this paper, a distributed secure position service system, named DISPOSER, is proposed and evaluated. A number of trusted servers are distributed in the network. Each node has a virtual home region (VHR). Servers residing in a node's VHR handle the position service regarding to the node, such as position update and position retrieving. DISPOSER keeps the position information private and prevents the position from being misused by a compromised user for tracing purposes. A region‐based local broadcast approach has been designed to reduce the control overhead for information distribution within a VHR. Mechanisms for improving system robustness have been proposed. Analytical results show that while DISPOSER meets the security requirements, it achieves a high system robustness at a relatively low control overhead. Copyright © 2006 John Wiley & Sons, Ltd.
Microarray detection of novel nuclear RNA substrates for the exosome
Authors: Houalla Rym , Devaux Frédéric , Fatica Alessandro , Kufel Joanna , Barrass David , Torchet Claire , Tollervey David 
Published: May 2006

AbstractMicroarray analyses were performed on yeast strains mutant for the nuclear‐specific exosome components Rrp6p and Rrp47p/Lrp1p or the core component Rrp41p/Ski6p, at permissive temperature and following transfer to 37 °C. 339 mRNAs showed clearly altered expression levels, with an unexpectedly high degree of heterogeneity in the different exosome mutants. In contrast, no clear alterations were seen in strains lacking the cytoplasmic exosome component Ski7p. 27 mRNAs that were overexpressed in each strain defective in the nuclear exosome are good candidates for regulation by nuclear turnover. These included the mRNA for the autoregulated RNA‐binding protein Nrd1p. Northern and primer extension analyses confirmed the elevated NRD1 mRNA levels in exosome mutants, and revealed the accumulation of truncated 5′ fragments of the mRNA. These contain a predicted Nrd1p‐binding site, potentially sequestering the protein and disrupting its autoregulation. Several genes located immediately downstream of independently transcribed snoRNA genes were overexpressed in exosome mutants, presumably due to stabilization of the products of transcription termination read‐through. Further analyses indicated that many snoRNA and snRNA genes are inefficiently terminated, but read‐through transcripts into downstream ORFs are normally rapidly degraded by the exosome. Copyright © 2006 John Wiley & Sons, Ltd.
Automatic Detection of Patients with Nosocomial Infection by a Computer-Based Surveillance System: A Validation Study in a General Hospital
Authors: Pokorny L. , Rovira A. , Martín-Baranera M. , Gimeno C. , Alonso-Tarrés C. , Vilarasau J. 
Published: May 2006

Objective.To validate an automated system for the detection of patients with nosocomial infection (NI) in an intensive care unit (ICU).Design.Retrospective analysis of data from the hospital information system. We applied 3 different NI suspicion criteria (positive microbiology reports, antibiotic administration, and diagnosis of clinical infection) and compared the results to those of a prospective NI incidence study done in the ICU during the same period (1999-2002).Setting.A 250-bed general hospital in Barcelona, Spain.Patients.From April 15, 1999, through June 30, 2002, 1380 patients were admitted to the ICU. Of these, 1043 had an ICU stay of more than 24 hours and were included in the study.Results.At least one NI suspicion criterion was present for 242 patients (23.2%); 2 criteria were present for 184 patients (17.6%); and all 3 criteria were present for 112 (11.7%). Comparison of hospital information system data to the results of the prospective study indicated that the combination of 2 criteria demonstrated the most satisfactory sensitivity (94.3%; 95% confidence interval [CI], 79.5%-99.0%) and specificity (83.6%; 95% CI, 76.8%-88.9%). The positive predictive value was 55.9% (95% CI, 42.5%-68.6%); the negative predictive value was 98.5% (95% CI, 94.2%-99.7%). The system could assign a site of infection for 90.4% of the NIs detected.Conclusion.The hospital information system was a useful tool for retrospectively detecting patients with an NI during the ICU stay. Given its high sensitivity, it may be useful as an alert for the NI team.
Use of Multistate Models to Assess Prolongation of Intensive Care Unit Stay Due to Nosocomial Infection
Authors: Beyersmann J. , Gastmeier P. , Grundmann H. , Bärwolff S. , Geffers C. , Behnke M. , Rüden H. , Schumacher M. 
Published: May 2006

Background.Reliable data on the costs attributable to nosocomial infection (NI) are crucial to demonstrating the real cost-effectiveness of infection control measures. Several studies investigating this issue with regard to intensive care unit (ICU) patients have probably overestimated, as a result of inappropriate study methods, the part played by NIs in prolonging the length of stay.Methods.Data from a prospective study of the incidence of NI in 5 ICUs over a period of 18 months formed the basis of this analysis. For describing the temporal dynamics of the data, a multistate model was used. Thus, ICU patients were counted as case patients as soon as an NI was ascertained on any particular day. All patients were then regarded as control subjects as long as they remained free of NI (time-to-event data analysis technique).Results.Admitted patients (n = 1,876) were observed for the development of NI over a period of 28,498 patient-days. In total, 431 NIs were ascertained during the study period (incidence density, 15.1 NIs per 1,000 patient-days). The influence of NI as a time-dependent covariate in a proportional hazards model was highly significant (P< .0001, Wald test). NI significantly reduced the discharge hazard (hazard ratio, 0.72 [95% confidence interval, 0.63-0.82])—that is, it prolonged the ICU stay. The mean prolongation of ICU length of stay due to NI ( ± standard error) was estimated to be 5.3 ± 1.6 days.Conclusions.Further studies are required to enable comparison of data on prolongation of ICU length of stay with the results of various study methods.
Prospective 3-Year Surveillance for Nosocomial and EnvironmentalLegionella pneumophila: Implications for Infection Control
Authors: Boccia S. , Laurenti P. , Borella P. , Moscato U. , Capalbo G. , Cambieri A. , Amore R. , Quaranta G. , Boninti F. , Orsini M. , Branca G. , Fadda G. , Spica V. Romano , Ricciardi G. 
Published: May 2006

Objectives.To perform a 3-year, prospective surveillance program for legionnaires disease (LD) in a large university hospital in Rome, and to assess the usefulness of the hospital water monitoring program in predicting the risk of nosocomial LD.Methods.Samples from patients with new cases of nosocomial pneumonia were sent for legionella laboratory investigations. Meanwhile, water samples for bacteriological analysis were collected every 6 months from high- and medium-risk hospital wards (10 in total).Legionella pneumophilaisolates collected were serotyped and analyzed by pulsed-field gel electrophoresis.Results.From June 2001 through May 2004, the pneumonia surveillance identified one case of nosocomial LD among 43 cases of nosocomial pneumonia (2.3%). Environmental investigations detectedL. pneumophilain 12 (18.7%) of the 64 water samples, of which 50% belonged to serogroup 1. TheL. pneumophilacount and the percentage of positive locations never exceeded 102colony-forming units/L and 20%, respectively, except when the LD nosocomial case occurred (positive water samples, 40%; I. pneumophila count, <102colony-forming units/L). Genotyping showed 3 prevalent clones ofL. pneumophilain the water distribution network, of which one persisted over the 3 years. One clone contained 3 differentL. pneumophilaserogroups (2, 4, and 6).Conclusions.The low incidence of nosocomial cases of LD appears to be associated with a low percentage (<20%) of positive water samples per semester and with a low contamination level (<102colony-forming units/L). An infection control system for nosocomial LD should, therefore, be based on both environmental and clinical surveillance, together with the appropriate maintenance of the hospital water distribution system.
High Rate of Negative Results of Tuberculin and QuantiFERON Tests Among Individuals With a History of Positive Skin Test Results
Authors: Friedman Lloyd N. , Nash Esther R. , Bryant June , Henry Susan , Shi Julia , D'Amato Joyce , Khaled Ghada H. , Russi Mark B. , O'Connor Patrick G. , Edberg Stephen C. , Pisani Margaret A. , Cain Hilary C. , Tanoue Lynn , Weissman David N. 
Published: May 2006

Objectives.To evaluate individuals at high risk for tuberculosis exposure who had a history of a positive tuberculin skin test (TST) result in order to determine the prevalence of unsuspected negative TST results. To confirm these findings with the QuantiFERON-TB test (QFT), an in vitro whole-blood assay that measures tuberculin-induced secretion of interferon-γ.Methods.This survey was conducted from November 2001 through December 2003 at 3 sites where TST screening is regularly done. Detailed histories and reviews of medical records were performed. TSTs were placed and read by 2 experienced healthcare workers, and blood was drawn for QFT. Any subject with a negative result of an initial TST during the study (induration diameter, <10 mm) underwent a second TST and a second QFT. The TST-negative group comprised individuals for whom both TSTs had an induration diameter of <10 mm. The confirmed-negative group comprised individuals for whom both TSTs yielded no detectable induration and results of both QFTs were negative.Results.A total of 67 immunocompetent subjects with positive results of a previous TST were enrolled in the study. Of 56 subjects who completed the TST protocol, 25 (44.6%; 95% confidence interval [CI], 31.6%-57.6%) were TST negative (P<.001). Of 31 subjects who completed the TST protocol and the QFT protocol, 8 (25.8%; 95% CI, 10.4%-41.2%) were confirmed negative (P<.005).Conclusions.A significant proportion of subjects with positive results of a previous TST were TST negative in this study, and a subset of these were confirmed negative. These individuals' TST status may have reverted or may never have been positive. It will be important in future studies to determine whether such individuals lack immunity to tuberculosis and whether they should be considered for reentry into tuberculosis screening programs.