RE

Distribution by Scientific Domains
Distribution within Chemistry

Kinds of RE

  • Reynold number re
  • number re


  • Selected Abstracts


    Theoretical Study of Remote Substituent Effects on X,H(X=CH2, NH, O) Bond Dissociation Energies of Azulene

    CHINESE JOURNAL OF CHEMISTRY, Issue 7 2007
    Yi-Yun Yu
    Abstract In the study, the X,H (XCH2, NH, O) bond dissociation energies (BDE) of para -substituted azulene (Y-C10H8X-H) were predicted theoretically for the first time using Density Functronal Theory (DFT) methods at UB3LYP/6-311++g(2df,2p)// UB3LYP/6-31+g(d) level. It was found that the substituents exerted similar effects on the X,H BDE of azulene as those on benzene, except for 6-substituted 2-methylazulene. Owing to the substituent-dipole interaction, the reaction constants (,+) of 2- and 6-Y-C10H8X-H (XNH and O only) varied violently. The origin of the substituent effects on the X,H BDE of azulene was found, by both GE/RE and SIE theory, to be directly associated with variation of the radical effects, although the ground effects also played a modest role in determining the net substituent effects. [source]


    RE: Interview and Reflections with Dr. John Ochsner

    CONGENITAL HEART DISEASE, Issue 4 2009
    Article first published online: 24 JUL 200
    First page of article [source]


    Cardiac autonomic function and baroreflex changes following 4 weeks of resistance versus aerobic training in individuals with pre-hypertension

    ACTA PHYSIOLOGICA, Issue 3 2009
    S. R. Collier
    Abstract Aim:, Cardiac autonomic modulation and baroreflex sensitivity (BRS) are altered in individuals with hypertension. Aerobic exercise (AE) training has been shown to improve both measures, yet little is known about the effects of resistance exercise (RE). The purpose of this study was to examine the heart rate variability (HRV) and BRS following 4 weeks of resistance or aerobic training in a population with borderline high blood pressure (BP). Methods:, Twenty-nine mild hypertensives were recruited and randomly assigned to 4 weeks of RE or AE training. Before and after training, resting measures of HRV frequencies and BRS were obtained. Results:, There was a significant decrease in resting systolic BP for both exercise training modes (RE 136 ± 3.0 pre- to 132 ± 3.4 post-training vs. AE 142 ± 4.0 pre- to 137 ± 3.6 mmHg post-training, P = 0.019). Diastolic BP decreased significantly following both exercise training modes (RE 78 ± 1.31 pre to 74 ± 1.1 post vs. AE 80 ± 1.7 pre to 77 ± 1.6 mmHg post, P = 0.002). A significant time by training mode interaction for low frequency : high frequency (HF) ratio (P = 0.017) with AE decreasing the ratio (275.21 ± 67.28 to 161.26 ± 61.49) and RE increasing this ratio (143.73 ± 65.00 to 227.83 ± 59.41). Natural log-transformed (ln) HRV values showed a time-by-training mode interaction for ln HF (P = 0.05) as ln HF increased (4.7 ± 0.38 to 5.4 ± 0.35 ms2) following AE and decreased (5.98 ± 0.37 to 5.76 ± 0.42 ms2) following RE. BRS increased following aerobic training and decreased after resistance training (6.74 ± 1.2 to 7.94 ± 1.3 and 10.44 ± 1.2 to 9.1 ± 1.2 ms mmHg,1 respectively, P = 0.021). Conclusions:, Aerobic exercise improved the autonomic nervous system (increasing vagal tone, reducing sympathovagal balance while increasing BRS) while RE showed no improvements in cardiac autonomic tone and decreased BRS. [source]


    Growth of single-grain GdBa2Cu3O7-x superconductors by top seeded infiltration and growth technique

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 3 2010
    Guo-Zheng Li
    Abstract The top seeded infiltration and growth technique (TSIG) is an effective way for the preparation of bulk REBa2Cu3O7-x (RE-123, where RE denotes rare earth) with finely dispersed RE2BaCuO5 (RE-211) particles compared to the conventional melt growth (MG) method. The nucleation temperature and the ending growth temperature are the most important parameters need to be optimized during the preparation of RE-123 bulks by the TSIG process. In this paper, the effects of these parameters on the growth of single-grain GdBa2Cu3O7-x (GdBCO) superconductors have been investigated experimentally. It is found that the temperature for the growth of single-grain GdBCO is in the region between 1040 °C and 1015 °C. In addition, the relation between growth rate and supercooling has been investigated in detail. The combined techniques of SEM and EDS were used to study the microstructure of the samples grown at different temperatures. Based on this, a two-step slow cooling method during the crystallization process is proposed for the fabrication of RE-123 bulks. Finally, the single-grain GdBCO samples of the diameters 20 mm and 30 mm were fabricated successfully by the TSIG technique, with the slow-cooling process in the temperature window 1030 °C,1020 °C for 60 h and 100 h respectively. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Academic performance in children with rolandic epilepsy

    DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 5 2008
    P Piccinelli MD
    The aim of this study was to investigate the frequency of reading, writing, and calculation disabilities in children with typical rolandic epilepsy (RE) and healthy control children. We also aimed to define the possible electroclinical markers of specific cognitive dysfunctions in RE. School abilities were evaluated and compared in 20 children (eight males, 12 females; mean age 10y 3mo [SD 1y 7mo]; range 7y 9mo-12y 9mo) consecutively diagnosed with typical RE, and a group of 21 healthy controls (nine males, 12 females; mean age 10y 4mo [SD 1y 8mo]; range 7y 6mo-13y 3mo). All the children received standardized neuropsychological tests. For each patient an exhaustive seizure diary was kept and all the sleep electroencephalogram (EEG) recordings were reviewed. Specific difficulties with reading, writing, and calculation (diagnosed according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition) were found in nine out of 20 children with RE and two out of 21 healthy controls (,2=0.01). The specific learning disabilities in the RE group were correlated with a marked increase in epileptiform discharges during sleep (,2=0.02) and an early onset of epilepsy (,2=0.02). Our findings suggest that seizure onset before age 8 years and epileptiform discharges (more than 50% of the sleep EEG recording) in several tracings over more than a year are relevant markers for identifying patients at risk of developing academic difficulties. [source]


    Redefining the role of lymphocytes in gastroesophageal reflux disease and eosinophilic esophagitis

    DISEASES OF THE ESOPHAGUS, Issue 5 2010
    B. Basseri
    SUMMARY Eosinophilic esophagitis (EoE) and reflux esophagitis (RE) overlap clinically and histologically. RE is characterized by epithelial infiltration with small numbers of neutrophils and eosinophils, EoE by a prominent eosinophilic infiltrate. Lymphocytic esophagitis (LE), a new entity characterized by peripapillary lymphocytosis, questions the role lymphocytes play in esophageal inflammation. We test the hypothesis that lymphocyte infiltration in RE differs from EoE. One blinded pathologist read esophageal biopsies from 39 RE and 39 EoE patients. Both groups demonstrated significant numbers of lymphocytes (RE 22.7 ± 2.2/HPF, EoE 19.8 ± 1.8/HPF). Eosinophils/HPF in RE and EoE were 2.8 ± 0.7 and 74.9 ± 8.2, respectively (P < 0.001). Neutrophils were uncommon in RE (0.26 ± 0.16/HPF) and EoE (0.09 ± 0.04; P = 0.07). Eight of the 39 RE specimens had ,50 lymphocytes in ,1 HPF. Two were consistent with LE. There was an inverse correlation between numbers of eosinophils and lymphocytes in EoE (R = ,0.47; P = 0.002), and no correlation between them in RE (R = 0.18; P = 0.36). The patients with EoE who used antireflux medications had fewer lymphocytes (16.3 ± 1.3 vs 22.2 ± 2.3/HPF; P = 0.030) and eosinophils (55.6 ± 5.2 vs 76.0 ± 8.7/HPF; P = 0.042) than those who did not. The pathological role of lymphocytes in RE and EoE may be underestimated. Our observation that 5% of the RE specimens meet histopathological criteria for LE potentially blurs the line between these entities. The observation that eosinophil counts are lower in EoE when antireflux meds are used supports the notion that reflux plays a role in the clinical expression of EoE. [source]


    Reflux esophagitis and columnar-lined esophagus after cervical esophagogastrostomy (following esophagectomy)

    DISEASES OF THE ESOPHAGUS, Issue 2 2010
    K. Nishimura
    SUMMARY Reflux esophagitis (RE) and columnar-lined esophagus (CLE) are frequently observed after esophagectomy. The incidence of these conditions according to time and to the route of esophageal reconstruction after esophagectomy remains unknown. The aim of this study was to clarify any changes and differences of the incidence of RE and CLE in patients who underwent gastric tube reconstruction after esophagectomy. A hundred patients who underwent cervical esophagogastrostomy after resection of the thoracic esophagus were included in this study. We reviewed their endoscopic findings at 1 month, at 1 year and at 2 years after surgery, and compared the incidence rates of RE and CLE with the passage of time and among the three reconstruction routes; a subcutaneous route, a retrosternal route, and a posterior mediastinal route. The incidence rate of RE was 42%, 37% and 38%, at 1 month, 1 year and at 2 years after surgery, respectively. There was no significant difference in the incidence of RE according to the time after surgery. The incidence rate of severe RE (Grade C and D in the Los Angeles Classification) was 9% percent at 1 month after surgery, 18% at 1 year after surgery and 22% at 2 years after surgery, significantly increasing with passage of time. The incidence rate of CLE was 0% at 1 month after surgery, 14% at 1 year after surgery and 40% at 2 years after surgery, significantly increasing with passage of time. No difference was observed in the incidence of RE and that of CLE among the three routes of esophageal reconstruction. Severe RE and CLE increase with passage of time after cervical esophagogastrostomy. Therefore, careful endoscopic follow-up is necessary for such patients irrespective of the route of esophageal reconstruction. [source]


    Genetic polymorphisms in glutathione S-transferases T1, M1 and P1 and susceptibility to reflux esophagitis

    DISEASES OF THE ESOPHAGUS, Issue 6 2006
    B. Liu
    SUMMARY., Recent studies indicate that the prevalence of reflux esophagitis (RE) in China is increasing. RE is one of the most common esophageal complications associated with gastroesophageal reflux disease (GERD) and RE-Barrett's esophagus-esophageal adenocarcinoma (EAC) sequence has been considered as an histogenesis model for EAC in Western countries. RE is only present in a subset of patients with GERD, suggesting an altered susceptibility to RE may exist in these GERD individuals. However, the genetic changes related with high susceptibility to RE is largely unknown. The polymorphisms in glutathione S-transferases (GSTs) T1, M1 and P1 have been reported with high susceptibity to esophageal cancer in Chinese people. The present case-control study was thus undertaken to characterize the genetic polymorphisms of GSTs and their correlation with susceptibility to RE. One hundred and nine patients with RE, 97 patients with nonerosive reflux disease (NERD) and 97 normal controls were recruited in this study. All the subjects were from Beijing, China, and received endoscopic examination and questionnaires for RE. Genomic DNA was extracted from the lymphocytes of peripheral blood for each subject. Genotypes of the GSTM1 and GSTT1 genes were analyzed by a multiplex PCR method. A,G polymorphism of codon 104 of the GSTP1 gene was detected using PCR-based restriction fragment length polymorphisms (RFLP). The variant GSTP1 genotypes (*A/*B,*B/*B) was found with a high frequency in the case with RE (40%), and followed by NERD (25%) and normal control (22%). The differences were statistically significant (P < 0.05). The risk for RE increased 2.42-fold [odds ratio (OR); 95% confidence interval (95% CI), 2.42 (1.22,4.80)] in the subjects with variant GSTP1 genotype. The subjects with positive variant GSTP1 genotypes and negative H. pylori infection showed increasing tendency for risk of RE [OR (95% CI), 2.67 (1.06,6.70)]. However, the subjects with GSTT1 and GSTM1 polymorphisms did not show any correlation with high risk for RE or NERD. No significant interactions were identified between the variant GSTs and cigarette smoking, or alcohol drinking and subtype of RE. The present result suggests that GSTP1 genetic polymorphism may be one of the high susceptibility factors involved in the mechanisms of RE. H. pylori infection may play a protective role against RE. [source]


    Evidence of shared genetic risk factors for migraine and rolandic epilepsy

    EPILEPSIA, Issue 11 2009
    Tara Clarke
    Summary Purpose:, Evidence for a specific association between migraine and rolandic epilepsy (RE) has been conflicting. Children with migraine frequently have electroencephalographic (EEG) abnormalities, including rolandic discharges, and approximately 50% of siblings of patients with RE exhibit rolandic discharges. We assessed migraine risk in RE probands and their siblings. Methods:, We used cohort and reconstructed cohort designs to respectively assess the relative risk of migraine in 72 children with RE and their 88 siblings using International Classification of Headache Disorders (ICHD-2) criteria. Incidences were compared in 150 age and geographically matched nonepilepsy probands and their 188 siblings. We used a Cox proportional hazards model, using age as the time base, adjusting hazard ratios (HRs) for sex in the proband analysis, and for sex and proband migraine status in the sibling analysis. Results:, Prevalence of migraine in RE probands was 15% versus 7% in nonepilepsy probands, and in siblings of RE probands prevalence was 14% versus 4% in nonepilepsy siblings. The sex-adjusted HR of migraine for an RE proband was 2.46 [95% confidence interval (CI) 1.06,5.70]. The adjusted HR of having ,1 sibling with migraine in an RE family was 3.35 (95% CI 1.20,9.33), whereas the HR of any one sibling of a RE proband was 2.86 (95% CI 1.10,7.43). Discussion:, Migraine is strongly comorbid in RE and independently clusters in their siblings. These results suggest shared susceptibility to migraine and RE that is not directly mediated by epileptic seizures. Susceptibility gene variants for RE may be tested as risk factors for migraine. [source]


    High Risk of Reading Disability and Speech Sound Disorder in Rolandic Epilepsy Families: Case,Control Study

    EPILEPSIA, Issue 12 2007
    Tara Clarke
    Summary Purpose: Associations between rolandic epilepsy (RE) with reading disability (RD) and speech sound disorder (SSD) have not been tested in a controlled study. We conducted a case,control study to determine whether (1) RD and SSD odds are higher in RE probands than controls and (2) an RE proband predicts a family member with RD or SSD, hence suggesting a shared genetic etiology for RE, RD, and SSD. Methods: Unmatched case,control study with 55 stringently defined RE cases, 150 controls in the same age range lacking a primary brain disorder diagnosis, and their siblings and parents. Odds ratios (OR) were calculated by multiple logistic regression, adjusted for sex and age, and for relatives, also adjusted for comorbidity of RD and SSD in the proband. Results: RD was strongly associated with RE after adjustment for sex and age: OR 5.78 (95% CI: 2.86,11.69). An RE proband predicts RD in family members: OR 2.84 (95% CI: 1.38,5.84), but not independently of the RE proband's RD status: OR 1.30 (95% CI: 0.55,12.79). SSD was also comorbid with RE: adjusted OR 2.47 (95%CI: 1.22,4.97). An RE proband predicts SSD in relatives, even after controlling for sex, age and proband SSD comorbidity: OR 4.44 (95% CI: 1.93,10.22). Conclusions: RE is strongly comorbid with RD and SSD. Both RD and SSD are likely to be genetically influenced and may contribute to the complex genetic etiology of the RE syndrome. Siblings of RE patients are at high risk of RD and SSD and both RE patients and their younger siblings should be screened early. [source]


    Adhesive bonding of titanium,aluminum,niobium alloy with nine surface preparations and three self-curing resins

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2003
    Hiroaki Yanagida
    The purpose of the current study was to evaluate the adhesive performance of metal conditioners when used for bonding between auto-polymerizing methacrylic resins and a titanium alloy. Disk specimens were cast from a titanium,aluminum,niobium (Ti,6Al,7Nb) alloy, air-abraded with alumina, and bonded with 24 combinations of eight metal conditioners (Acryl Bond, ACB; All-Bond 2 Primer B, ABB; Alloy Primer, ALP; Cesead II Opaque Primer, COP; Metafast Bonding Liner, MBL; Metal Primer II, MPII; MR Bond, MRB; Super-Bond liquid, SBL) and three autopolymerizing methacrylic resins (Repairsin, RE; Super-Bond C & B, SB; Tokuso Rebase; TR). Unprimed specimens were used as controls. Shear bond strengths were determined both before and after thermocycling (4,60°C, 20, 000 cycles). The ALP-SB group recorded the greatest post-thermocycling bond strength (21.8 MPa) followed by the COP-SB group (17.8 MPa) and the MPII-SB group. The post-thermocycling bond strengths of the unprimed-SB group and the ALP-RE group were statistically comparable. No significant differences were found among the nine TR resin groups, and these groups showed the lowest bond strength. In conclusion, the use of one of the three conditioners (ALP, COP, and MPII) in combination with the SB resin is recommended for bonding the Ti,6Al,7Nb alloy. [source]


    Universal Behavior and Electric-Field-Induced Structural Transition in Rare-Earth-Substituted BiFeO3

    ADVANCED FUNCTIONAL MATERIALS, Issue 7 2010
    Daisuke Kan
    Abstract The discovery of a universal behavior in rare-earth (RE)-substituted perovskite BiFeO3 is reported. The structural transition from the ferroelectric rhombohedral phase to an orthorhombic phase exhibiting a double-polarization hysteresis loop and substantially enhanced electromechanical properties is found to occur independent of the RE dopant species. The structural transition can be universally achieved by controlling the average ionic radius of the A-site cation. Using calculations based on first principles, the energy landscape of BiFeO3 is explored, and it is proposed that the origin of the double hysteresis loop and the concomitant enhancement in the piezoelectric coefficient is an electric-field-induced transformation from a paraelectric orthorhombic phase to the polar rhombohedral phase. [source]


    AATYK1A phosphorylation by Cdk5 regulates the recycling endosome pathway

    GENES TO CELLS, Issue 7 2010
    Tetsuya Takano
    Trafficking of recycling endosomes (REs) is regulated by the small GTPase, Rab11A; however, the regulatory mechanism remains elusive. Apoptosis-associated tyrosine kinase 1A (AATYK1A) is a Ser/Thr kinase expressed highly in brain. We have recently shown that AATYK1A localizes to Rab11A-positive RE and is phosphorylated at Ser34 by cyclin-dependent kinase 5 (Cdk5). Here, we have investigated a role of AATYK1A and its phosphorylation in recycling endosomal trafficking using Chinese hamster ovary-K1 (CHO-K1) cells. AATYK1A localizes predominantly to Rab11A-positive pericentrosomal endocytic recycling compartment (ERC). Phosphorylation at Ser34 of AATYK1A disrupts its accumulation in the pericentrosomal ERC. Consistently, phosphorylation-mimic mutant (AATYK1A-S34D) did not accumulate in the ERC and additionally attenuated ERC formation. ERC formation suppression can be reversed by constitutively active Rab11A-Q70L, suggesting a functional link between AATYK1A phosphorylation and Rab11A activity. Although no direct interaction between AATYK1A and Rab11A could be detected, the exchange of guanine nucleotides bound to Rab11A was significantly reduced in the presence of the phosphorylation-mimic AATYK1A-S34D. Together, our results reveal a regulatory role for AATYK1A in the formation of pericentrosomal ERC. They furthermore indicate that Cdk5 can disrupt ERC formation via Ser34 phosphorylation of AATYK1A. Finally, our data suggest a mechanism by which AATYK1A signaling couples Cdk5 to Rab11A activity. [source]


    Reconstruction with radial forearm flaps after ablative surgery for hypopharyngeal cancer

    HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 4 2003
    Joseph Scharpf MD
    Abstract Background. Patients afflicted with advanced hypopharyngeal cancer must contend with both potentially poor survival prognosis and a compromised quality of remaining life. After extensive ablative surgery, it is imperative to use a reliable, low morbidity reconstructive strategy that will allow for an expedient reconstitution of speech and swallowing. Methods. Retrospective review of the records of 28 patients who underwent pharyngoesophageal reconstruction with radial forearm free flaps (RFFF) between 1996 and 2001 by a single surgeon (RE). Analysis was confined to patients requiring complete tubulation of the RFFF. Perioperative mortality, morbidity, and functional evaluation based on the parameters of speech and swallowing were analyzed. Results. Completely tubulated RFFF were required in 25 patients. There was 100% RFFF survival with no perioperative mortalities. The median hospital stay was 8.0 days. All patients acquired a reconstitution of oral alimentation; median time to swallowing was 18.0 days. Fourteen of 16 patients (93%) were able to rely on TEP speech as their main modality of communication. Two patients (8%) had early fistulas develop, and 5 (20%) had late fistulas develop. Nine patients (36%) required mechanical dilatation; five of the nine patients required only one dilatation. Conclusion. Review of our experience has confirmed the reliability and excellent functional outcome associated with this flap. © 2003 Wiley Periodicals, Inc. Head Neck 25: 261,266, 2003 [source]


    Impact of Helicobacter pylori Eradication Therapy on Histologic Change in the Distal Esophagus

    HELICOBACTER, Issue 4 2006
    Masanori Toyoda
    Abstract Background:, Although cases of reflux esophagitis (RE) developing after treatment to eradicate Helicobacter pylori have been discussed in some detail, no reports are available concerning the histologic examination of RE both before and after eradication therapy. Materials and methods:, Sixty-one patients and 111 specimens were investigated using endoscopic and histologic techniques. The histologic findings including basal zone height, papillar height, Ki-67 labeling index, and COX-2 expression before and after treatment for H. pylori infection were compared with those in normal controls and patients with endoscopic RE. Results:, Twelve months after eradication therapy, the incidence of newly developed endoscopic RE was 20% (5/25). Basal zone height and papillar height had increased at 1 month, but had returned to pretreatment levels after 12 months of eradication therapy. The Ki-67 labeling index was significantly increased 1 and 12 months after eradication therapy compared to values before treatment. COX-2 expression gradually increased after the treatment. The phenomena linked to esophagitis appeared after eradication therapy. However, the severity and extent of these signs were not so high after the treatment of H. pylori than those in patients with overt reflux esophagitis. Focusing on the patients with hiatal hernia, papillar height and Ki-67 labeling index increased significantly after eradication therapy, values being almost the same as those in the patients with endoscopic RE. Conclusions:, Hiatal hernia plays an important role in the possible occurrence of hidden RE after treatment for a H. pylori infection. [source]


    Negative Association Between Helicobacter pylori Infection and Reflux Esophagitis in Older Patients: Case-Control Study in Japan

    HELICOBACTER, Issue 1 2000
    Ken Haruma
    Background. Recent studies have clarified a close association between H. pylori infection and gastritis, peptic ulcer disease, and gastric cancer, but there is little information concerning the relationship between H. pylori infection and reflux esophagitis (RE). We investigated the relationship between H. pylori, RE, and corpus gastritis. Subjects and Methods. Ninety-five patients with RE and 190 sex- and age-matched asymptomatic healthy controls demonstrating no localized lesions in the upper GI tract were studied and evaluated for H. pylori infection, histologic gastritis, serum gastrin, and pepsinogens (PGs). Results.H. pylori infection was significantly lower in RE patients than in asymptomatic controls (41% vs. 76%, p < .01). Histologic gastritis of both the antrum and corpus was significantly less frequent (antrum; p < .01, corpus; p < .01), and serum levels of PGI and the PG I/II ratio were significantly higher in RE patients than in controls (PGI; p < .05, PG I/II ratio; p < .01). When the subjects were divided into two age groups (59 years of age and younger and 60 years of age and older), a significant difference was found only among patients over 60 years of age (29% vs. 85%, p < .01). Among subjects in this age group, gastritis in both the antrum and corpus were significantly milder in RE patients than in controls. Although the prevalence of H. pylori infection was similar between the two groups of patients under 59 years of age, corpus gastritis was significantly milder in patients than in controls (p < .05). Conclusions. A significantly low prevalence of H. pylori infection was found in RE patients over 60 years of age but not in those under 59 in comparison with sex- and age-matched controls. The relative lack of corpus gastritis might play a role in the pathogenesis of RE in our population through preservation of the acid secretion area. [source]


    Appropriate vertical discretization of Richards' equation for two-dimensional watershed-scale modelling

    HYDROLOGICAL PROCESSES, Issue 1 2004
    Charles W. Downer
    Abstract A number of watershed-scale hydrological models include Richards' equation (RE) solutions, but the literature is sparse on information as to the appropriate application of RE at the watershed scale. In most published applications of RE in distributed watershed-scale hydrological modelling, coarse vertical resolutions are used to decrease the computational burden. Compared to point- or field-scale studies, application at the watershed scale is complicated by diverse runoff production mechanisms, groundwater effects on runoff production, runon phenomena and heterogeneous watershed characteristics. An essential element of the numerical solution of RE is that the solution converges as the spatial resolution increases. Spatial convergence studies can be used to identify the proper resolution that accurately describes the solution with maximum computational efficiency, when using physically realistic parameter values. In this study, spatial convergence studies are conducted using the two-dimensional, distributed-parameter, gridded surface subsurface hydrological analysis (GSSHA) model, which solves RE to simulate vadose zone fluxes. Tests to determine if the required discretization is strongly a function of dominant runoff production mechanism are conducted using data from two very different watersheds, the Hortonian Goodwin Creek Experimental Watershed and the non-Hortonian Muddy Brook watershed. Total infiltration, stream flow and evapotranspiration for the entire simulation period are used to compute comparison statistics. The influences of upper and lower boundary conditions on the solution accuracy are also explored. Results indicate that to simulate hydrological fluxes accurately at both watersheds small vertical cell sizes, of the order of 1 cm, are required near the soil surface, but not throughout the soil column. The appropriate choice of approximations for calculating the near soil-surface unsaturated hydraulic conductivity can yield modest increases in the required cell size. Results for both watersheds are quite similar, even though the soils and runoff production mechanisms differ greatly between the two catchments. Copyright © 2003 John Wiley & Sons, Ltd. [source]


    Agile requirements engineering practices and challenges: an empirical study

    INFORMATION SYSTEMS JOURNAL, Issue 5 2010
    Balasubramaniam Ramesh
    Abstract This paper describes empirical research into agile requirements engineering (RE) practices. Based on an analysis of data collected in 16 US software development organizations, we identify six agile practices. We also identify seven challenges that are created by the use of these practices. We further analyse how this collection of practices helps mitigate some, while exacerbating other risks in RE. We provide a framework for evaluating the impact and appropriateness of agile RE practices by relating them to RE risks. Two risks that are intractable by agile RE practices emerge from the analysis. First, problems with customer inability and a lack of concurrence among customers significantly impact agile development. Second, risks associated with the neglecting non-functional requirements such as security and scalability are a serious concern. Developers should carefully evaluate the risk factors in their project environment to understand whether the benefits of agile RE practices outweigh the costs imposed by the challenges. [source]


    Update on medical treatment of ejaculatory disorders,

    INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 6 2002
    A. KAMISCHKE
    Summary Among the treatment modalities for ejaculatory disorders pharmacological treatment is the least invasive option. In this review, medical treatments for retrograde ejaculation (RE) and anejaculation (AE) are discussed systematically. Thirty-six studies dealing with patients with RE and 40 with AE evaluated the use of medical treatment and were included in this review. In addition four articles dealing with prostatic massage in anejaculatory patients were considered. Sperm quality in patients with retrograde and AE is often impaired. In patients with RE no differences in response to medical treatment could be detected between the different underlying diagnoses. Compared with ephedrine, imipramine and chlorpheniramine + phenylpropanalamine showed significantly higher reversal rates, while differences between the other treatments were not significant. Regarding the reversal of AE, the alpha agonistic drugs were significantly inferior to treatment with parasympathetic drugs. Of the different alpha agonistic medical treatments for the reversal of AE, milodrin showed significantly better rates than imipramine (p = 0.008), pseudoephidrine (p = 0.02) and ephedrine (p = 0.044), while all other treatments were not significantly different (p = 0.4). In conclusion, medical treatment for reversal of RE offers a realistic chance of conceiving offspring naturally and should be the treatment modality of first choice. In contrast, in AE, medical treatment cannot be recommended generally as treatment of first choice as it shows low overall success rates compared with electrovibration stimulation and electroejaculation. Under consideration of the mostly uncontrolled design of the majority of studies published, controlled clinical trials comparing different treatment options appear urgently warranted. [source]


    Effects of Rare-Earth Dopants on the Ferroelectric and Pyroelectric Properties of Strontium Barium Niobate Ceramics

    INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 6 2009
    Yingbang Yao
    Effects of various rare-earth (RE) dopants (Y3+, La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Tm3+, Dy3+, Er3+, and Yb3+) on the dielectric, ferroelectric, and pyroelectric properties of Sr0.5Ba0.5Nb2O6 (SBN50) ceramics were investigated. In the present studies, the doping concentrations of all the RE dopants were fixed at 1 mol%. Their potential usefulness in pyroelectric applications was discussed based on their measured pyroelectric detectivity figure of merit (FOM). On the basis of our studies, for RE dopants with atomic numbers smaller than Nd, their dielectric constants were greatly increased, while for RE dopants with atomic numbers larger than Sm, their dielectric constants as well as dielectric losses became smaller. Among various dopants, Eu-doped SBN showed the most improved ferroelectric properties. Its remnant polarization (Pr) was increased to 4.86 ,C/cm2 as compared with 3.23 ,C/cm2 obtained in undoped SBN50. On the other hand, Gd-doped SBN exhibited the largest pyroelectric coefficient of 168 ,C/m2 K, which was over three times of that of the undoped sample (49 ,C/m2 K). The work shows that Gd-doped SBN exhibits the greatest potential for pyro-applications because it bears the largest FOM of 0.45 × 10,5 Pa,0.5 [Correction: After online publication on 11/05/2008, an error was found in this article. The original value, 1.35×10,5 Pa,0.5, was incorrect. The data has been replaced with the correct value.]. [source]


    Reconstruction of the North Atlantic Oscillation, 1429,1983

    INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 12 2001
    Mary F. Glueck
    Abstract The North Atlantic Oscillation (NAO) is considered to be the dominant mode of winter atmospheric variability in the Northern Hemisphere (Barnston AG, Livezey RE. 1987. Classification, seasonality and persistence of low frequency atmospheric circulation patterns. Monthly Weather Review115: 1083,1126), especially in the North Atlantic region. A better understanding of its recent variability in the context of pre-instrumental period variations is critical for prediction purposes. A 555-year (1429,1983) multi-proxy reconstruction of the cool season NAO, calibrated against the Lisbon,Iceland (LISJHI) NAO, is presented. Predictor variables include tree-ring chronologies from Morocco and Finland, GISP2 ,18O annual series, and a GISP2 snow accumulation record. Although the reconstructed values are generally lower than the instrumental values during the calibration period (1863,1983), the final reconstruction does capture the low frequency of the instrumental NAO. The reconstruction compares favourably with existing shorter NAO reconstructions and with the instrumental NAO. The variability in the reconstructed NAO is also discussed within the context of lengthy regional climate records. Results suggest that the occurrence and length of the recent persistently high phase of the NAO are not unusual over the 555-year period of time, but that the magnitude of some of the instrumental values may, in fact, be unique. Copyright © 2001 Royal Meteorological Society [source]


    Physical properties of biopolymers containing natamycin and rosemary extract

    INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 2 2009
    Hasan Türe
    Summary Antifungal biopolymers were prepared by incorporating natamycin (NA) and NA + rosemary extract (RE) into wheat gluten (WG) and methyl cellulose (MC) films. Interaction between antimicrobial agents and biopolymers was determined with mid-infrared spectroscopy and scanning electron microscopy (SEM). Water vapour permeability and mechanical properties of these films were also measured. Mid-infrared spectroscopy did not indicate any interaction. SEM observations showed that NA crystallises at high concentrations in biopolymers. There were no significant changes in water vapour permeabilities of biopolymers containing active agents at P < 0.05. While NA incorporation did not result in any changes in mechanical properties of WG films a reduction in tensile strength was observed for MC films containing high concentration of NA. In general, active agent incorporation into WG and MC films did not result in any considerable changes in their physical properties that could affect their application. [source]


    An MDE modeling framework for measurable goal-oriented requirements

    INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 8 2010
    Fernando Molina
    It is a proved fact that the appropriate management of requirements is one of the most influential factors in the success of software development projects. With the advent of the model-driven engineering (MDE) development paradigm, the need for formal gathering mechanisms, which provide the necessary degree of nonambiguity and detail, has led to the proposal of a myriad of requirements metamodels. However, a great disparity exists, both in the concepts/relationships and in the underlying semantics involved in each metamodel. Moreover, most existing proposals lack backward (e.g., alignment with business goals) or forward (e.g., connection with validation methods) traceability. In view of this situation, this article proposes a "measurable requirements metamodel" that offers support to the elicitation of measurable requirements. This support is based on the explicit connection of goals, requirements, and measures, thus fostering a goal-driven measurable requirements engineering (RE) perspective. Additionally, since it is well known that metamodels only reflect the abstract syntax of the modeling language, the proposed metamodel also includes a notation (concrete syntax) which, for reasons of understandability, is based on the goal-oriented requirements language (GRL) notation. This notation is supported by a unified modeling language (UML) profile that facilitates its adoption by RE analysts in the context of any UML-based software engineering process. To support this proposal, an Eclipse tool has been developed. This tool permits the integration of measurable requirements as a driving force in the context of a given MDE development process. © 2010 Wiley Periodicals, Inc. [source]


    Laparoscopic nephropexy: Treatment outcome and quality of life

    INTERNATIONAL JOURNAL OF UROLOGY, Issue 1 2004
    YOSHIYUKI MATSUI
    Abstract Background:, The recent introduction of laparoscopic procedures has markedly altered urological surgery. Laparoscopic nephropexy has attracted the attention of urologists as a treatment for nephroptosis. Herein, we describe our experiences and quality-of-life outcome of laparoscopic nephropexy and discuss its indications and surgical techniques. Methods:, From May 1998 to February 2002, six female patients, ranging in age from 20 to 64 years (median age 39.8 years), with symptomatic nephroptosis underwent laparoscopic nephropexy. Mean preoperative downward kidney displacement was 2.25 vertebral bodies (range 2,2.5) and all affected kidneys were tilted at orthostasis. One patient underwent nephropexy through the transperitoneal approach and the remaining patients underwent nephropexy through the retroperitoneal approach. To evaluate surgical results, postoperative follow-up interview (pain visual analog scale and the short-form 36 (SF-36) health survey questionnaire) and objective examinations were performed. Results:, All procedures were accomplished without complication. Postoperative intravenous pyelography correctly confirmed fixed kidney in both supine and erect positions. All patients reported an improvement of symptoms approximately 1 month after nephropexy and no symptoms have recurred during the follow-up period (range 6.3,50.7 months). On the SF-36, two domains, including role limitations due to emotional problems (RE) and mental health (MH), exhibited significant improvement postoperatively (P = 0.0405 and P = 0.0351, respectively). Conclusions:, Laparoscopic, in particular retroperitoneoscopic, nephropexy yields excellent outcomes and greatly improves general health-related quality of life, particularly mental status, as a minimally invasive treatment for symptomatic nephroptosis. [source]


    Antimicrobial finishing of regular and modified nylon-6 fabrics

    JOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2008
    S. E. Shalaby
    Abstract A simple, efficient, and practically applicable functional approach for improvement antimicrobial properties of nylon-6 fabrics and increase the washing durability of biofunctions was developed. This finishing approach is based on grafting of the fabrics with methacrylic acid (MAA) to create additional carboxylic groups in nylon-6 macromolecules, followed by subsequent reaction with dimethylalklbenzyl ammonium chloride (DMABAC) solution under alkaline conditions. The carboxylic groups react with cationic agent through ionic interaction, which led to the immobilization of QAS on nylon-6 fabrics. This immobilization was proofed through determination of nitrogen content, applying scanning electron microscopy (SEM), and FTIR microscopy. The effect of treatment conditions on salt uptake (SUT) on nylon-6 fabrics and reaction efficiency (RE) was investigated. The antimicrobial assessment of regular and grafted with PMAA nylon-6 fabrics treated with DMABAC revealed that both types of fabrics are characterized before washing, by quite strong biocide effect on Bacillus mycoides, Escherichia coli and Candida albicans. The role of grafting nylon-6 fabrics before treatment with salt on durability of antimicrobial functions seems to be more significant as the samples were repeatedly washed. Even after Laundring 10 times the grafted samples could still provide 80%, 100%, and 87.5% microbial reduction against B. mycoides, E. coli and C. albicans, respectively, in contrast with 42.6%, 65.6%, and 42.5% in case of regular nylon-6 fabrics. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008. [source]


    A randomized comparison of plateletpheresis with the same donors using four blood separators at a single blood center,

    JOURNAL OF CLINICAL APHERESIS, Issue 4 2002
    Grace C. Tenorio
    Abstract At one blood center, each of 20 donors underwent plateletpheresis on four blood cell separators in random order. We compared the CS3000+, Amicus V 2.41, MCS Plus, and Spectra LRS V 7 Turbo regarding platelet (PLT) yield, pre- and post-procedure PLT counts, percent fall in donor PLT count, process time, efficiency, PLT product and donor PLT volume (MPV). Using , 150 × 109 PLTs/L pre-donation counts, a goal was set of 4.5 × 1011 PLTs unit in up to 100 minutes processing time. Results were (mean values) PLT yields of Amicus, Spectra, CS3000+, and MCS Plus: 4.3, 4.6, 4.3, 4.0 × 1011 PLTS, respectively; percent donor PLT fall: 24, 32, 30, 29%, respectively; processing times: 50, 74, 87, 101 minutes, respectively; relative efficiency (RE): 2.2, 1.6, 1.2,1.0, respectively (based on the MCS Plus performance with RE of 1 = 4 × 109 PLTS/min); PLT product MPV: 6.7, 7.4, 6.8,7.1 fL, respectively; pre-procedure donor MPV: 7.7, 7.3, 7.6 and 7.6 fL, respectively; and percent donor MPV change: ,5.2, 0, ,6.6, and ,10%, respectively. Significant changes in the donor MPV were noted (P < 0.05) but could not be related to product MPV. Spectra seemed to collect larger PLTs (higher MPV); the significance remains unknown for both donors and recipients. Importantly, all four separators gave acceptable and comparable PLT yields (P < 0.05) with Spectra trending higher. The short process time and high RE together indicate highly efficient collections particularly by Amicus and Spectra. J. Clin. Apheresis 17:170,176, 2002. © 2002 Wiley-Liss, Inc. [source]


    Influence of hypobaric hypoxia on bispectral index and spectral entropy in volunteers

    ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 7 2009
    T. IKEDA
    Background: Hypoxia has been shown to change electroencephalogram parameters including frequency and amplitude, and may thus change bispectral index (BIS) and spectral entropy values. If hypoxia per se changes BIS and spectral entropy values, BIS and spectral entropy values may not correctly reflect the depth of anaesthesia during hypoxia. The aim of this study was to examine the changes in BIS and spectral entropy values during hypobaric hypoxia in volunteers. Methods: The study was conducted in a high-altitude chamber with 11 volunteers. After the subjects breathed 100% oxygen for 15 min at the ground level, the simulated altitude increased gradually to the 7620 m (25,000 ft) level while the subjects continued to breathe oxygen. Then, the subjects discontinued to breath oxygen and breathed room air at the 7620 m level for up to 5 min until they requested to stop hypoxic exposure. Oxygen saturation (SpO2), heart rate, 95% spectral edge frequency (SEF), BIS, response entropy (RE), and state entropy (SE) of spectral entropy were recorded throughout the study period. Results: Of the 11 subjects, seven subjects who underwent hypoxic exposure for 4 min were analysed. SpO2 decreased to 69% at the 7620 m level without oxygen. However, SEF, BIS, RE, and SE before and during hypoxic exposure were almost identical. Conclusion: These data suggest that hypoxia of oxygen saturation around 70% does not have a strong effect on BIS and spectral entropy. [source]


    Conformational populations of ligand-sized molecules by replica exchange molecular dynamics and temperature reweighting

    JOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 7 2010
    Hisashi Okumura
    Abstract The use of the replica exchange (RE) molecular dynamics (MD) method for the efficient estimation of conformational populations of ligand-sized molecules in solution is investigated. We compare the computational efficiency of the traditional constant temperature MD technique with that of the parallel RE molecular dynamics method for a series of alkanes and rilpivirine (TMC278), an inhibitor against HIV-1 reverse transcriptase, with implicit solvation. We show that conformational populations are accurately estimated by both methods; however, replica exchange estimates converge at a faster rate, especially for rilpivirine, which is characterized by multiple stable states separated by high-free energy barriers. Furthermore, convergence is enhanced when the weighted histogram analysis method (WHAM) is used to estimate populations from the data collected from multiple RE temperature replicas. For small drug-like molecules with energetic barriers separating the stable states, the use of RE with WHAM is an efficient computational approach for estimating the contribution of ligand conformational reorganization to binding affinities. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010 [source]


    Chemical graph theory and n -center electron delocalization indices: A study on polycyclic aromatic hydrocarbons

    JOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 10 2007
    Marcos Mandado
    Abstract Relations between aromaticity indices derived from chemical graph theory and those based on 6-center electron delocalization are investigated for a series of polybenzenoid hydrocarbons. Aromatic stabilization obtained by means of the effective scaled electron delocalization is highly correlated to the resonance energy, RE, obtained both from SCF MO calculations and conjugated ring circuits model. Local aromaticity of benzene rings is discussed using two different criteria, in one of them aromaticity is just given by the cyclic , -electron conjugation of the ring, whereas terms involving more than one ring are also considered in the other one. Indices derived from chemical graph theory and those obtained from the 6-center electron delocalization give rise to the same local aromaticity. Moreover, 6-center electron delocalization provides more quantitative information. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007 [source]


    Epidemiological study of symptomatic gastroesophageal reflux disease in China: Beijing and Shanghai

    JOURNAL OF DIGESTIVE DISEASES, Issue 1 2000
    Pan Guozong
    OBJECTIVE: To explore the 1-year point prevalences (July,September 1996) of symptomatic gastroesophageal reflux (GER), gastroesophageal reflux disease (GERD) and reflux esophagitis (RE) in the adult population of two Chinese city-regions (Beijing and Shanghai) and to identify the conditions that predispose patients to GERD. METHODS: Phase I: 5000 residents of the two regions aged between 18 and 70 years were studied via a questionnaire. The study was carried out by cluster sampling from city, suburban and rural areas by using simple random sampling. Symptom scores (Sc) of the intensity and frequency of heartburn, acid reflux and regurgitation within 1 year of the time of study were taken as indices of acid reflux (highest score, Sc = 18) and Sc , 6 indicated the presence of symptomatic GER. Phase II: a small number of patients who were identified as having symptomatic GER in the survey were enrolled in a case, control study using gastroscopy and 24-h pH monitoring to obtain correct diagnostic rates of GERD and RE. Estimates of the prevalence of GERD and RE were then adjusted according to the rates of correct diagnosis. RESULTS: A total of 4992 subjects completed the survey, 2.5% had heartburn once daily, 8.97% had symptomatic GER (Sc , 6) and the male to female ratio was 1:1.11. Point prevalences for the year for GERD and RE were 5.77 and 1.92%, respectively. Stratified analysis indicated that the prevalence of symptomatic GER in Beijing (10.19%) was higher than that in Shanghai (7.76%) and there was also a higher prevalence of GER in males, manual laborers, people from rural areas and people older than 40 years of age in Beijing as compared with Shanghai. Stepwise logistic analysis indicated that GER had a close relationship with dental, pharyngolaryngeal disorders and respiratory diseases. The conditions that predispose patients to GERD are (OR, odds ratio): age > 40 (OR = 1.01), eating greasy/oily food (OR = 6.56), overeating (OR = 1.99), tiredness (OR = 2.35), emotional stress (OR = 2.22), pregnancy (OR = 6.80) and constipation (OR = 1.65). CONCLUSIONS: Gastroesophageal reflux disease is a common disease in the adult Chinese population and it is more common in Beijing than in Shanghai. [source]