bluuebunny/crossref_metadata_2025_split huggingface dataset:
Frequency of cyclic lumbar loading is a risk factor for cumulative trauma disorder
Authors: Lu Dawei , Le Peter , Davidson Bradley , Zhou Bing He , Lu Yun , Patel Vikas , Solomonow Moshe 
Published: May 2008

AbstractEpidemiologic studies indicate that repetitive (cyclic) occupational activities lead to a cumulative trauma disorder (CTD), and the frequency or velocity of the movement is one of the risk factors. Experimental neurophysiological evidence to confirm the epidemiology is not available. The response of the multifidus muscles to cyclic loading in anterior lumbar flexion–extension was assessed to test the hypothesis that high‐frequency loading may induce an acute neuromuscular disorder leading to CTD. Two groups of feline preparations were subjected to cyclic loading with a peak of 20 N: one at 0.25 HZ and the second at 0.5 HZ, with an equal number of cycles. Electromyogram (EMG), lumbar displacement and load were recorded throughout the loading periods and during single‐cycle tests over a 7‐hour rest period following the load–rest sessions. A model was developed to quantify the creep and neuromuscular responses, and analysis of variance (ANOVA) was applied to assess significance of the results. The group exposed to 0.5 HZ exhibited spontaneous spasms followed by sustained spasms during the loading periods. During the 7‐hour recovery period, a significant (P < 0.001) delayed hyperexcitability as well as sustained spasms of the multifidi were present in the last 5 hours, confirming a significant (P < 0.024 to P < 0.042) acute neuromuscular disorder. High‐frequency cyclic loading of the lumbar spine may trigger a severe acute neuromuscular disorder, as evidenced by the sustained spasms and delayed hyperexcitability, and should be considered as a risk factor. We suggest that workers avoid high‐frequency exposure to cyclic activity in order to prevent the development of cumulative trauma disorder. Muscle Nerve, 2008
Neurogenic detrusor overactivity: Comparison between complete and incomplete spinal cord injury patients
Authors: Moslavac S. , Dzidic I. , Kejla Z. 
Published: May 2008

AbstractAimsTo compare leak‐point intravesical pressure and cystometric capacity in complete and incomplete spinal cord injury (SCI) patients with neurogenic detrusor overactivity (NDO).MethodsRetrospective study of filling cystometry at non‐physiological filling rate in 80 SCI patients at rehabilitation or annual check‐up using Dantec Etude urodynamic machine.ResultsFifty neurologically complete (ASIA (American Spinal Injury Association) A) and 30 incomplete (ASIA B–E) were diagnosed with neurogenic detrusor overactivity, all with suprasacral level of injury. Mean Pves leak‐point pressure (Pves LPP) at cystometric capacity for ASIA A group was 79 ± 30 cmH2O (range 26–140) and mean Pves LPP for ASIA B–E group was 70 ± 29 cmH2O (range 25–130). There was no significant difference between groups (P = 0.234). Mean CC (cystometric capacity) for ASIA A group was 239 ± 107 ml (range 47–526) and mean CC for ASIA B–E group was 227 ± 125 ml (range 42–500). Again, no significant difference was found (P = 0.655).ConclusionsNo difference in cystometric capacity and intravesical leak point pressure at terminal detrusor overactivity was shown between complete and incomplete spinal cord injury patients in our survey, that is, represented findings are equally unfavorable for both groups. Incomplete SCI patients with NDO should be tested with cystometry and observed with same caution as we proceed in complete SCI patients. Neurourol. Urodynam. 27:504–506, 2008. © 2008 Wiley‐Liss, Inc.
Modeling the clinical assessment of men with suspected obstructed voiding using Bayes' Theorem
Authors: Caffarel Jennifer , Griffiths Clive , Pickard Robert , Robson Wendy , Drinnan Michael 
Published: May 2008

AbstractAimsPressure‐flow studies (PFS) are the only reliable way to diagnose bladder outlet obstruction (BOO) in men with lower urinary tract symptoms (LUTS). However, in routine clinical practice, BOO is usually inferred by any of a number of tests (symptoms, flow rate, prostate size…). Bayes' Theorem provides a mathematical method, which may be similar to the process used by clinicians, for combining the results of multiple tests to reach a diagnosis. We have applied Bayes' Theorem to the results of several tests known weakly to predict BOO in men with LUTS to assess if they improve the diagnostic accuracy of a flow rate test which alone is known to predict obstruction moderately well.MethodsWe applied Bayes' Theorem to data from 50 patients using Qmax alone and with the inclusion of additional variables (IPSS, PSA, and residual urine), to establish individual probabilities of BOO. The chi‐squared statistic (with trend) was used to compare the relative diagnostic values, against the BOO index calculated from the results of subsequent PFS.ResultsThe diagnostic value of Qmax alone (chi‐squared = 9.2, P = 0.002), was superior than that for the Bayesian model using the combination of tests available (chi‐squared = 4.9, P = 0.026).ConclusionsAlthough in our sample relevant additional tests do not improve the diagnostic power of Qmax as a predictor of BOO, we believe the Bayesian approach is conceptually suited to modeling clinical decision making but may be better tested for a more clinically relevant outcome such as treatment response. Neurourol. Urodynam. 27:797–801, 2008, © 2008 Wiley‐Liss, Inc.
Numerical studies of a nonlinear heat equation with square root reaction term
Authors: Buckmire Ron , McMurtry Karl , Mickens Ronald E. 
Published: May 2008

AbstractInterest in calculating numerical solutions of a highly nonlinear parabolic partial differential equation with fractional power diffusion and dissipative terms motivated our investigation of a heat equation having a square root nonlinear reaction term. The original equation occurs in the study of plasma behavior in fusion physics. We begin by examining the numerical behavior of the ordinary differential equation obtained by dropping the diffusion term. The results from this simpler case are then used to construct nonstandard finite difference schemes for the partial differential equation. A variety of numerical results are obtained and analyzed, along with a comparison to the numerics of both standard and several nonstandard schemes. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009
Thermal and mechanical properties of electron beam irradiated poly(vinyl chloride)/polystyrene blends
Authors: Senna Magdy M.H. , Hussein Yousry A. , Abdel‐Moneam Yasser K. 
Published: May 2008

AbstractThe effect of electron beam irradiation on the thermal and mechanical properties of poly(vinyl chloride)/polystyrene (PVC/PS) blends and PVC/PS blends containing epoxidized natural rubber (ENR) was studied. The thermogravimetric analysis study showed that the thermal decomposition of the plasticized PVC individual polymer goes through two stages, whereas PS decomposes through one stage. However, the temperature of the maximum rate of reaction (Tmax) of PS is much higher than that for PVC and their blends. Meanwhile, the Tmax was found to increase with increasing PS ratios in the blend. The thermal stability of PVC/PS blends was greatly increased after electron beam irradiation in comparison with unirradiated blends. Moreover, the addition of ENR to PVC/PS increased the thermal stability. On the other hand, the mechanical properties in terms of tensile strength and elongation at break of PVC/PS blends are lower than pure PVC polymer because of the immiscibility. However, the addition of ENR to the PVC/PS (80/20) blend increased the elongation at break from 114 to 321% associated with a small effect on the tensile properties. These behaviors were supported by structure morphology studies observations, which indicate an improvement in the interfacial adhesion between the phases. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
The effect of gestational age on the outcome of second‐trimester termination of pregnancies for foetal abnormalities
Authors: Lo T. K. , Lau W. L. , Lai F. K. , Lam H. , Tse H. Y. , Leung W. C. , Chin R. K. H. 
Published: May 2008

AbstractObjectiveTo explore the effect of gestational age on the outcome of second‐trimester termination of pregnancies for foetal abnormalities.MethodA retrospective study was conducted on 280 pregnancies terminated for foetal abnormalities in the second trimester using vaginal misoprostol. The gestational age at termination was divided into three groups: 13–16 weeks, 17–20 weeks and 21–23 weeks. The likelihood of (1) abortion within 24 h of commencement of misoprostol, (2) incomplete abortion and (3) experiencing significant side effects was compared among these three gestational groups after adjusting for maternal age, parity and body mass index (BMI).ResultsCompared to termination after 20 weeks, pregnancy termination for foetal abnormality before 17 weeks of gestation was associated with higher chance of incomplete abortion (OR 2.2, 95% CI 1.07–4.61, p = 0.032) and lower chance of experiencing significant side effects (OR 0.11, 95% CI 0.01–0.91, p = 0.041).ConclusionWomen undergoing pregnancy termination for foetal abnormalities in the early second trimester should be informed of possible higher chance of incomplete abortion. Copyright © 2008 John Wiley & Sons, Ltd.
Regression of fetal cerebral abnormalities by primary cytomegalovirus infection following hyperimmunoglobulin therapy
Authors: Nigro Giovanni , Torre Renato La , Pentimalli Henny , Taverna Paola , Lituania Mario , de Tejada Begoňa Martinez , Adler Stuart P. 
Published: May 2008

AbstractObjectiveTo assess the effects of maternal and intra‐amniotic hyperimmunoglobulin (HIG) infusions among cytomegalovirus (CMV) infected fetuses with ultrasound abnormalities following a primary CMV infection.Patients and MethodsThe subjects were fetuses with CMV‐associated cerebral and other ultrasound abnormalities. Three mothers were treated with HIG infusions during pregnancy and two were untreated. Fetal ventricle size, organ echodensity and placental thickness were measured by ultrasound before and after HIG infusions. The children were evaluated between 3 and 7 years of age.ResultsThe ventriculomegaly of all three fetuses of HIG‐treated mothers regressed and the ascites, hepatic echodensities, periventricular echodensities, and intestinal echodensities disappeared. Their sensorial, mental and motor development was normal at 4, 4.7, and 7 years of age. In contrast, both infants born of untreated mothers had signs and symptoms of severe CMV cerebropathy.ConclusionThe outcomes of the infants born to HIG‐treated mothers support the efficacy of HIG as a treatment for CMV‐infected fetuses with ultrasound cerebral abnormalities. Copyright © 2008 John Wiley & Sons, Ltd.
The best approach for early prediction of fetal gender by using free fetal DNA from maternal plasma
Authors: Picchiassi Elena , Coata Giuliana , Fanetti Alessia , Centra Michela , Pennacchi Luana , Di Renzo Gian Carlo 
Published: May 2008

AbstractObjectivesDetection of free fetal DNA (ffDNA) in maternal blood during pregnancy has given rise to the possibility of developing new noninvasive approaches for early prenatal diagnosis.On a large‐scale study, two protocols of real‐time polymerase chain reaction (PCR) were compared in order to establish which Y‐specific locus, either multicopy DYS14 or single copy SRY sequence, was the most suitable for developing a test with high diagnostic efficiency for early fetal gender assessment. The second aim was to assess whether the combination of the two detection systems could increase the performance of the prenatal test.MethodsWe analyzed 145 plasma samples from healthy pregnant women between 11 and 12 weeks of singleton gestation. For each sample, fetal gender was determined by using both protocols (DYS14 and SRY) during the same real‐time PCR run.ResultsThe data obtained by the DYS14 and SRY assays showed an efficiency in fetal gender prediction of 97.9 and 80%, respectively. It is not advisable to combine the two protocols because this association does not help in further improvements in fetal gender prediction.ConclusionsDYS14 assay is the best approach for early fetal gender assessment because it is more sensitive, accurate, and efficient than the SRY assay. Copyright © 2008 John Wiley & Sons, Ltd.
Interstitial laser therapy for fetal reduction in monochorionic multiple pregnancy: loss rate and association with aplasia cutis congenita
Authors: O'Donoghue Keelin , Barigye Olivia , Pasquini Lucia , Chappell Lucy , Wimalasundera Ruwan C. , Fisk Nicholas M. 
Published: May 2008

AbstractObjectiveTo evaluate experience with interstitial laser therapy for intrafetal vascular ablation in monochorionic (MC) multiple pregnancy.MethodsMC pregnancies that underwent fetal reduction between 1998 and 2007 by interstitial laser therapy were reviewed. Indications were twin reversed arterial perfusion sequence (TRAP) (n = 10), twin‐to‐twin transfusion (6), discordant abnormality (7) or growth (1) and high‐order multiples (6).ResultsThirty pregnancies treated at 15 weeks (median, range: 11 weeks–20 weeks, 5 days) had no technical failures but four manifested procedure‐related amniorrhexis. Four of 38 remaining fetuses suffered intrauterine death (IUFD) within 24 h, giving an early procedure‐related fetal loss rate of 10% per pregnancy and 11% per fetus. A further five IUFDs occurred within 2 weeks, giving a maximum procedure‐related loss rate of 27% per pregnancy and 24% per fetus. Median gestation at delivery was 37 weeks (18 weeks, 1 day–41 weeks, 3 days) for pregnancies continuing > 2 weeks. Perinatal survival was 26 of 38 (68%) in nonreduced fetuses. Two of 26 neonates (8%) were diagnosed with aplasia cutis congenita (ACC).ConclusionInterstitial laser therapy in complicated MC pregnancies carries significant risks of unintended fetal loss and may be associated with ACC. Copyright © 2008 John Wiley & Sons, Ltd.
Diffusion of interferon beta in Iran and its utilization in Tehran
Authors: Palesh Mohammad , Jonsson Pia Maria , Jamshidi Hamidreza , Wettermark Björn , Tomson Göran , Fredrikson Sten 
Published: May 2008

AbstractPurposeThere are few studies on the diffusion of expensive new therapies in low‐ or middle‐income countries. The objectives of this study were to describe the diffusion of interferon beta for the treatment of patients with multiple sclerosis (MS) in Iran and to analyze its use in a cohort of 890 patients in Tehran registered in the Iranian MS Society (IMSS) registry.MethodsData on the diffusion of interferon beta drugs from 2000 to 2004 in Iran were obtained from the Ministry of Health (MOH). Data on the utilization of interferon beta in selected patient groups were collected from routine clinical data of the IMSS in a sample of population in Tehran province from 2003 to 2005.ResultsInterferon beta had a rapid diffusion in Iran during the study period, and it was used in all 28 provinces in 2004, however, much less in the poor provinces. Interestingly, interferon beta was prescribed to 68% of the patients in Tehran registered in the IMSS registry during 2003–2005. The usage of interferon beta as registered in the IMSS was higher (p < 0.0001) among insured than uninsured patients.ConclusionThe use of interferon beta treatment has grown considerably in Iran. In Tehran, interferon beta seems to be mainly used by young ambulatory patients with relapsing–remitting MS, indicating a rational drug use. Copyright © 2008 John Wiley & Sons, Ltd.
Material characterization of components and assembled behavior of a composite liner for rehabilitation of cast iron pressure pipes
Authors: Brown Michael , Fam Amir , Moore Ian D. 
Published: May 2008

AbstractWork is underway to determine the stability limit states for a cast in place composite liner system used to repair cast iron pressure water pipes. To establish its performance in bridging ring fractures, perforations, and other failures in the cast iron “host” pipe, it is important that the material characteristics of this composite liner be determined. This study characterizes the mechanical properties of this liner in both the longitudinal and circumferential directions, and develops a method to achieve this goal. A technique is developed to form the liner from its individual components and prepare coupons with end tabs. Test results for coupons oriented parallel to the axis of the pipe (i.e., in the longitudinal direction) agree well with those obtained from coupons cut from a liner exhumed from an actual field installation. Since the coupons formed in the laboratory are flat, the same technique is used to test the liner in the hoop (or circumferential) direction. Tensile strength and stiffness in the hoop direction are 45% higher than that in the longitudinal direction. Tests performed on the individual components of the liner are also reported, and these explain the bilinear stress–strain response. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Nonisothermal crystallization of high density polyethylene and nanoscale calcium carbonate composites
Authors: Huang Jiann‐Wen , Wen Ya‐Lan , Kang Chiun‐Chia , Tseng Wei‐Jen , Yeh Mou‐Yung 
Published: May 2008

AbstractNonisothermal crystallization of high density polyethylene (HDPE)/maleic anhydride‐modified HDPE(manPE)/nanoscale calcium carbonate (CaCO3) nanocomposite was investigated by means of wide angle X‐ray diffraction (WAXD), polarized optical microscopy (POM), and differential scanning calorimetry (DSC). WAXD indicated that the crystallinity was reduced with the addition of CaCO3. The spherulite size of HDPE increased in the presence of manPE, but decreased when CaCO3 was added from observation of POM. A modified Avrami analysis, Ozawa analysis, and Liu analysis were applied to the nonisothermal crystallization process. Crystallizability followed the order: HDPE/manPE/CaCO3 > HDPE/CaCO3 > HDPE/manPE > HDPE when undercooling was taken into account. Dependence of the effective activation energy on the relative crystallinity was estimated by the Friedman equation, and the results were used to calculate the parameters (Kg and U*) of Lauritzen‐Hoffman's equation by Vyazovkin's method. These results indicate that the addition of maleic anhydride groups and CaCO3 tend to promote the nucleation of spherulites on their surfaces and lead to epitaxial growth of the crystallites. But at the same time, manPE and CaCO3 particles may hinder the transport of the molecule chains resulting in a decrease of the crystallization growth rate. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
A new method for producing high melt strength polypropylene with reactive extrusion
Authors: Tang Hongxia , Dai Wenli , Chen Baiquan 
Published: May 2008

AbstractA high‐melt‐strength polypropylene (HMSPP) was prepared using a twin‐screw reactive extruder from a commercial isotactic polypropylene through two stages, first, maleic anhydride is grafted to polypropylene to obtain a maleic anhydride‐grafted polypropylene (PP‐g‐MA), and then the grafted polymer is reacted with epoxy to extend the branched chain. Fourier transformed infrared spectroscopy indicated that maleic anhydride was grafted on polypropylene and reacted with epoxy. Melt flow rate and sag resistance test showed that the melt strength of the HMSPP improved considerably. Differential scanning calorimetry test showed that the long chain branches (LCBs) act as a nucleating agent in the crystallization of the HMSPP, which leads to a high crystallization temperature and crystallinity. Furthermore, the LCB efficiency of the HMSPP can also be calculated by analyzing its rheological property. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Temperature dependence of electrical resistivity in carbon nanofiber/unsaturated polyester nanocomposites
Authors: Natsuki Toshiaki , Ni Qing‐Qing , Wu Shi‐Hong 
Published: May 2008

AbstractThis article described the temperature dependence of electrical resistivity for carbon nanofiber (CNF)/unsaturated polyester resin (UPR) nanocomposites prepared by a solvent evaporation method. It was found that the CNF/UPR nanocomposites had quite low electrical percolation threshold due to CNFs having a large aspect ratio and being well dispersed into the UPR matrix. A sharp decrease in the electrical resistivity was observed at about 1 wt% CNF content. The influence of CNF content on the electrical resistivity was investigated as a function of temperature in detail. The nanocomposites showed a positive temperature coefficient effect for the resistivity, and had a strong temperature dependence near the percolation threshold. When the number of thermal cycles was increased, the electrical resistivity decreased and had a weak temperature dependence, especially in the case of melting temperature. Moreover, the size influences of CNFs on the electrical properties of nanocomposites were analyzed and discussed. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
A novel fabrication route for auxetic polyethylene, part 2: Mechanical properties
Authors: Webber R.S. , Alderson K.L. , Evans K.E. 
Published: May 2008

AbstractAuxetic ultra high molecular weight polyethylene (UHMWPE) has been fabricated by omitting the extrusion stage usually required to form the characteristic nodule‐fibril microstructure of this material. This new route consists of compaction followed by multiple sintering treatments, with the best results using two successive sintering treatments. This article examines the mechanical properties of cylindrical compacts subjected to between one and four successive sintering treatments. The indentation resistance of the double‐sintered material was found to be 2.5 times that of conventionally processed UHMWPE and similar to that found in the extruded form of auxetic polyethylene. The flexural strength and strain to failure increase dramatically with the first sintering treatment and then remain almost constant. This processing route has potential for the production of more complex, useful shapes than can currently be produced since it removes the limitations imposed by the geometry of the barrel required for the extrusion stage. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Influence of polydispersity of crystallizable segments on the properties of segmented block copolymers
Authors: Biemond G.J.E. , Feijen J. , Gaymans R.J. 
Published: May 2008

AbstractPoly(ether‐ester‐amide)s (PEEAs) based on poly(tetramethylene oxide) and tetra‐amide segments were synthesized by a solution/melt polymerization. The tetra‐amide segments (T6A6T) were based on adipic acid (A), terephthalic acid (T), and hexamethylene diamine (6), and were synthesized prior to the polymerization. Monodisperse tetra‐amide segments, i.e. T6A6T, as well as polydisperse segments, consisting of a mixture of uniform segments of diamide (T6T), tetra‐amide (T6A6T), and hexa‐amide (T6A6A6T), were utilized in the preparation of the PEEAs. In this way, a polydispersity index ranging from 1.0 to 1.09 could be obtained. In addition, a random copolymer, synthesized by a one‐pot polymerization, was also studied and the copolymer had a polydispersity of 1.2. The low polydispersity of the one‐pot synthesis amide segments was mainly due to the uneven reactivity of the terephthalic ester groups. The properties of copolymers were studied by DSC, FTIR, DMTA, compression set, and tensile set measurements. When the polydispersity of the amide segments was increased, the copolymers displayed a slower crystallization, a lower final crystallinity, a broader melting transition, a decreased storage modulus at room temperature, as well as a decreased yield strength and inferior elastic properties. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers