bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distinct protein kinases regulate SNAP‐25 expression in chromaffin cells
Authors: Montiel Carmen , Mendoza Isabel , García Carlos J. , Awad Yusfeye , García‐Olivares Jennie , Solís‐Garrido Luisa M. , Lara Hernan , García Antonio G. , Cárdenas Ana M. 
Published: January 2003

AbstractThe contribution of distinct Ca2+‐sensitive protein kinases to the regulation of the expression of the synaptosomal‐associated protein SNAP‐25 was examined in bovine chromaffin cells. Prolonged incubation with high K+(38 mM) or 1,1‐dimethyl‐4‐phenyl‐piperazinium (DMPP), a nicotinic receptor agonist, significantly increased SNAP‐25 protein and mRNA expression, as assessed by immunoblotting and semi‐quantitative RT‐PCR analysis. Both stimuli preferentially enhanced mRNA coding for the SNAP‐25a isoform. Increase of SNAP‐25 expression induced by K+or DMPP was inhibited over 70% by KN‐62 and KN‐93, two Ca2+/calmodulin‐dependent protein kinase (CaMK) inhibitors, whereas the inactive analogue KN‐92 only reduced the expression by 34%. The three compounds also inhibited the high K+‐elicited [Ca2+]isignal by 40%, suggesting that the effect of KN‐62 and KN‐93 was a combination of CaMK/ Ca2+influx inhibitory actions. Incubation of the cells with mitogen‐activated protein kinase (MAPK) inhibitors PD98059 and U0126 reduced protein expression elicited by high K+by 50%, but did not modify the response to DMPP. Interestingly, although protein kinase A (PKA) inhibition by H‐89 did not affect the high K+or DMPP‐induced SNAP‐25 expression, basal protein levels were significantly modified upon activation or inhibition of this pathway. Basal expression of SNAP‐25 was also modified by the protein kinase C (PKC) activator, phorbol 12‐myristate 13‐acetate, but not by Gö6976, a PKC‐α inhibitor, suggesting that the Ca2+‐insensitive PKC‐ϵ isoform control basal expression of SNAP‐25 in these cells. Taken together, these results provide the first evidence that diverse protein kinases might converge in the induction of SNAP‐25 expression in chromaffin cells. The preferential contribution of one or another kinase would depend on the physiological or experimental conditions. © 2002 Wiley‐Liss, Inc.
Studies on protein and its high‐molecular‐weight subunit composition in relation to chapati‐making quality of Indian wheat cultivars
Authors: Srivastava Alok K , Prasada Rao Ummiti J S , Haridas Rao Punaroor 
Published: January 2003

AbstractIn order to predict the suitability of wheat for chapati making, 15 Indian wheat cultivars were studied for various protein characteristics in relation to chapati‐making quality. The cultivars varied considerably in their protein characteristics and chapati‐making potential. Results clearly indicated that both quantitative and qualitative characteristics of proteins influenced the chapati‐making potential of cultivars. Puffed height, the important qualitative parameter of chapati, was positively correlated with protein content (r = 0.62, p < 0.05), gluten content (r = 0.79, p < 0.01), sodium dodecyl sulphate (SDS) sedimentation value (r = 0.57, p < 0.05) and Glu‐1 quality scores of high‐molecular‐weight (HMW) subunits (r = 0.66, p < 0.01). Overall quality score of chapati was positively correlated with gluten content (r = 0.64, p < 0.01), SDS sedimentation value (r = 0.60, p < 0.05) and Glu‐1 score (r = 0.58, p < 0.05). HMW subunit composition varied considerably among cultivars. Cultivars having 5 + 10 subunits at the Glu‐1D chromosome, a protein content of about 130 g kg−1 and SDS sedimentation value around 75 ml yielded excellent chapatis, while those having 2 + 12 subunits, a protein content of about 115 g kg−1 and SDS sedimentation value around 55 ml resulted in poor chapatis. Interestingly, the presence of the 1BL/1RS chromosome in cultivars had no adverse effect on chapati quality.© 2003 Society of Chemical Industry
Kinetic behaviour and stability of Escherichia coli ATCC27257 alkaline phosphatase immobilised in soil humates
Authors: Pilar María C , Ortega Natividad , Perez‐Mateos Manuel , Busto María D 
Published: January 2003

AbstractAlkaline phosphatase (EC 3.1.3.1) extracted from Escherichia coli ATCC27257 was immobilised by co‐flocculation with soil humates in the presence of Ca2+. The effects of time, temperature, pH and concentration of enzyme and support on immobilisation were studied. Between 58 and 92% of the added phosphatase was strongly bound to the humates, depending on the conditions of immobilisation used. Some characteristics of the humate–phosphatase complexes and of the free enzyme were compared. The enzymatic complexes showed values of Km (2.22 mM) and activation energy (33.4 kJ mol−1) similar to those of the free enzyme (2.00 mM and 27.6 kJ mol−1). The pH/activity profiles revealed no change in terms of shape or optimum pH (10.5) upon immobilisation of alkaline phosphatase. However, the immobilised enzyme showed maximal activity in the range of 80–100 °C, while the free enzyme had its highest activity at 60 °C. The thermal stability of alkaline phosphatase was enhanced by complexation to the soil humates.© 2003 Society of Chemical Industry
Use of neural networks for the prediction of frictional drag and transmission of axial load in horizontal wellbores
Authors: Sadiq Tanvir , B. Gharbi Ridha , C. Juvkam‐Wold Hans 
Published: January 2003

AbstractThe use of mud motors and other tools to accomplish forward motion of the bit in extended reach and horizontal wells allows avoiding large amounts of torque caused by rotation of the whole drill string. The forward motion of the drill string, however, is resisted by excessive amount of friction. In the presence of large compressive axial loads, the drill pipe or coiled tubing tends to buckle into a helix in horizontal boreholes. This causes additional frictional drag resisting the transmission of axial load (resulting from surface slack‐off force) to the bit. As the magnitude of the frictional drag increases, a buckled pipe may become ‘locked‐up’ making it almost impossible to drill further. In case of packers, the frictional drag may inhibit the transmission of set‐up load to the packer. A prior knowledge of the magnitude of frictional drag for a given axial load and radial clearance can help avoid lock‐up conditions and costly failure of the tubular.In this study a neural network model, for the prediction of frictional drag and axial load transmission in horizontal wellbores, is presented. Several neural network architectures were designed and tested to obtain the most accurate prediction. After cross‐validation of the Back Propagation Neural Network (BPNN) algorithm, a two‐hidden layer model was chosen for simultaneous prediction of frictional drag and axial load transmission. A comparison of results obtained from BPNN and General Regression Neural Network (GRNN) algorithms is also presented. Copyright © 2002 John Wiley & Sons, Ltd.
A simulation using a hybrid method for predicting fault zones ahead of a tunnel face
Authors: Lee In‐Mo , Kim Don‐Hee 
Published: January 2003

AbstractBy monitoring and analysing three‐dimensional absolute displacement during tunnel excavation, it is possible to predict discontinuity zones ahead of tunnel face. This paper presents results of the three‐dimensional displacement obtained from three‐dimensional simulations using hybrid method for assessing the effect of discontinuity zones on monitoring data. The influence of fault zones and in situ initial stresses on the three‐dimensional tunnel movement is evaluated. Copyright © 2002 John Wiley & Sons, Ltd.
Determination of burn‐in parameters and residual life for highly reliable products
Authors: Tseng Sheng‐Tsaing , Tang Jen , Ku In‐Hong 
Published: January 2003

AbstractToday, many products are designed and manufactured to function for a long period of time before they fail. Determining product reliability is a great challenge to manufacturers of highly reliable products with only a relatively short period of time available for internal life testing. In particular, it may be difficult to determine optimal burn‐in parameters and characterize the residual life distribution. A promising alternative is to use data on a quality characteristic (QC) whose degradation over time can be related to product failure. Typically, product failure corresponds to the first passage time of the degradation path beyond a critical value. If degradation paths can be modeled properly, one can predict failure time and determine the life distribution without actually observing failures. In this paper, we first use a Wiener process to describe the continuous degradation path of the quality characteristic of the product. A Wiener process allows nonconstant variance and nonzero correlation among data collected at different time points. We propose a decision rule for classifying a unit as normal or weak, and give an economic model for determining the optimal termination time and other parameters of a burn‐in test. Next, we propose a method for assessing the product's lifetime distribution of the passed units. The proposed methodologies are all based only on the product's initial observed degradation data. Finally, an example of an electronic product, namely contact image scanner (CIS), is used to illustrate the proposed procedure. © 2002 Wiley Periodicals, Inc. Naval Research Logistics, 2003
Scheduling with tool changes to minimize total completion time: A study of heuristics and their performance
Authors: Akturk M. Selim , Ghosh Jay B. , Gunes Evrim D. 
Published: January 2003

AbstractThe machine scheduling literature does not consider the issue of tool change. The parallel literature on tool management addresses this issue but assumes that the change is due only to part mix. In practice, however, a tool change is caused most frequently by tool wear. That is why we consider here the problem of scheduling a set of jobs on a single CNC machine where the cutting tool is subject to wear; our objective is to minimize the total completion time. We first describe the problem and discuss its peculiarities. After briefly reviewing available theoretical results, we then go on to provide a mixed 0–1 linear programming model for the exact solution of the problem; this is useful in solving problem instances with up to 20 jobs and has been used in our computational study. As our main contribution, we next propose a number of heuristic algorithms based on simple dispatch rules and generic search. We then discuss the results of a computational study where the performance of the various heuristics is tested; we note that the well‐known SPT rule remains good when the tool change time is small but deteriorates as this time increases and further that the proposed algorithms promise significant improvement over the SPT rule. © 2002 Wiley Periodicals, Inc. Naval Research Logistics, 2003
Optimal stopping in software testing
Authors: Morali Nilgun , Soyer Refik 
Published: January 2003

AbstractIn this paper we address the problem of how to decide when to terminate the testing/modification process and to release the software during the development phase. We present a Bayesian decision theoretic approach by formulating the optimal release problem as a sequential decision problem. By using a non‐Gaussian Kalman filter type model, proposed by Chen and Singpurwalla (1994), to track software reliability, we are able to obtain tractable expressions for inference and determine a one‐stage look ahead stopping rule under reasonable conditions and a class of loss functions. © 2002 Wiley Periodicals, Inc. Naval Research Logistics, 2003
Transient analysis of electro‐osmotic transport by a reduced‐order modelling approach
Authors: Qiao R. , Aluru N. R. 
Published: January 2003

AbstractTransient behaviour of electro‐osmotic transport in typical electrokinetic channels is studied in this paper. The time needed for the electro‐osmotic flow to reach steady‐state exhibits multiple time scales depending on whether the flow is governed by either a viscous force, electrokinetic force or by a combination of both. When an intersection is present in the electrokinetic channel, such as in a cross or a T‐channel, the flow in the main channel and in the intersection gets to steady‐state at different times.A weighted Karhunen–Loève (KL) decomposition method is proposed in this paper to generate the global basis function for reduced‐order simulation. The key idea in a weighted KL approach is that, instead of minimizing a least‐squares measure of ‘error’ between the linear subspace spanned by the basis functions and the observation space, we minimize the weighted ‘error’ between the two spaces. The global basis functions in a weighted KL approach can be generated by computing the singular value decomposition (SVD) of the matrix containing the weighted snapshots. We show that the weighted KL decomposition based reduced‐order model is computationally more efficient and can capture the multiple time scales encountered in electro‐osmotic transport much more effectively compared to the classical KL decomposition based reduced‐order model. Copyright © 2003 John Wiley & Sons, Ltd.
Comparative randomized trial of azithromycin versus erythromycin and amoxicillin for treatment of community‐acquired pneumonia in children
Authors: Kogan Ricardo , Martínez M. Angélica , Rubilar Lilian , Payá Ernesto , Quevedo Ilsa , Puppo Homero , Girardi Guido , Castro‐Rodriguez José A. 
Published: January 2003

AbstractOur objective was to compare the clinical efficacy of azithromycin vs. erythromycin and amoxicillin in the treatment of presumed bacterial community‐acquired pneumonia in ambulatory children, and to evaluate the etiologies of these illnesses. One hundred and ten children, aged 1 month to 14 years, were enrolled between January 1996–January 1999. Children were distributed into two groups according to clinical and radiological patterns: classic or atypical pneumonia. Patients with classic pneumonia were randomly assigned to receive oral amoxicillin 75 mg/kg/day for 7 days, or azithromycin 10 mg/kg/day for 3 days; patients with atypical pneumonia received azithromycin 10 mg/kg/day for 3 days, or erythromycin 50 mg/kg/day for 14 days. Chest X‐ray, clinical, and laboratory parameters were obtained on enrollment. Clinic visits were performed on days 3, 7, and 14, and chest X‐ray follow‐up on days 7 and 14. Microbiological diagnosis of classic pathogens was based on blood and bronchial secretion cultures. The diagnosis of atypical pathogens C. pneumoniae, C. trachomatis, and M. pneumoniae was based on PCR and serologic tests.Forty‐seven children met the criteria for classic pneumonia (23 children received azithromycin, and 24 received amoxicillin), and 59 children had atypical pneumonia (33 children were treated with azithromycin, and 26 with erythromycin). Demographic characteristics at enrollment were similar between children with classic pneumonia treated with azithromycin and erythromycin and children treated with azithromycin and erythromycin for atypical pneumonia. However, on day 7, children with classic pneumonia who received azithromycin normalized their chest X‐ray more often than those who received amoxicillin (81.0% vs. 60.9%, respectively, P = 0.009). The same was true for children with atypical pneumonia; their chest X‐rays had normalized by day 14 (100% in those with azithromycin vs. 81% in those with erythromycin, P = 0.059). Also, children with atypical pneumonia treated with azithromycin had earlier cessation of cough than children treated with erythromycin (3.6 ± 1.9 vs. 5.5 ± 3.6 days respectively, P = 0.02). There were only three children with side effects (mild diarrhea, all in the erythromycin group). Etiological agents were identified in 41% of children.In conclusion, azithromycin is an effective therapeutic option for the treatment of community‐acquired classic and atypical pneumonia in children. Pediatr Pulmonol. 2003; 35:91–98. © 2003 Wiley‐Liss, Inc.
Role of viruses and atypical bacteria in exacerbations of asthma in hospitalized children: A prospective study in the Nord‐Pas de Calais region (France)
Authors: Thumerelle C. , Deschildre A. , Bouquillon C. , Santos C. , Sardet A. , Scalbert M. , Delbecque L. , Debray P. , Dewilde A. , Turck D. , Leclerc F. 
Published: January 2003

AbstractWe studied the role of viruses and atypical bacteria in children hospitalized with exacerbated asthma by a prospective study of children with acute asthma admitted to the Department of Pediatrics in Lille, and to 15 hospitals in the Nord‐Pas de Calais region, from October 1, 1998–June 30, 1999. We included children aged 2–16 years with active asthma, defined as three or more recurrent episodes of reversible wheezing. The severity of asthma and of asthmatic exacerbations was recorded. Immunofluorescence assays (IFA) on nasopharyngeal secretions (NPS), serological tests, or both, were used for detection of influenza virus, respiratory syncytial virus (RSV), adenovirus, parainfluenza virus, and coronavirus. Polymerase chain reaction (PCR) assays on NPS were used for rhinovirus and enterovirus. Serological tests for Chlamydia pneumoniae and Mycoplasma pneumoniae were performed. A control group of asymptomatic asthmatic outpatients was examined for respiratory viruses (using IFA and PCR). Eighty‐two symptomatic children (mean age, 7.9 years) were examined. Viruses were detected in 38% (enterovirus, 15.8%; rhinovirus, 12%; RSV, 7.3%). Serological tests for atypical bacteria were positive in 10% of patients (C. pneumoniae, 5%; M. pneumoniae, 5%). Among the 27 control subjects (mean age, 7.9 years), one PCR was positive for enterovirus. There was no correlation between severity of chronic asthma or asthmatic exacerbations and the diagnosis of infection. Atypical bacterial pathogen infections were linked with prolonged asthmatic symptoms. In conclusion, we confirmed the high incidence of viral infection in acute exacerbations of asthma, especially enteroviruses or rhinoviruses. Persistent clinical features were more frequently associated with atypical bacterial infections, suggesting that these infections should be investigated and treated in cases of persistent asthmatic symptoms. Pediatr Pulmonol. 2003; 35:75–82. © 2003 Wiley‐Liss, Inc.
Asthma‐specific quality of life questionnaires in children: Are they useful and feasible in routine clinical practice?
Authors: Williams Jeff , Williams Kate 
Published: January 2003

AbstractThis study used well‐validated quality of life (QOL) instruments to compare the QOL scores achieved by children aged 7–17 years with the views of their parents of the effects of their child's asthma on family life. Also, a comparison was made between the child's QOL scores and the judgment of the clinician in charge in regard to asthma control.There was poor correlation between the overall scores of the children and the overall caregiver's score (r = 0.19, P = 0.18), and no correlation between the child's score and assessment of control given by the clinician in charge of the case (r = 0.02, P = 0.98).It is important to recognize that there may be little relationship between the concerns of the child regarding his or her asthma, the effects on the family as reported by a parent, and the clinician's view of asthma control. This recognition may significantly affect treatment planning with the family. The administration of the QOL instrument used in this study was straightforward and quite quick, with a mean time to completion of about 8 min. Pediatr Pulmonol. 2003; 35:114–118. © 2003 Wiley‐Liss, Inc.
Three‐minute step test to assess exercise capacity in children with cystic fibrosis with mild lung disease
Authors: Narang I. , Pike S. , Rosenthal M. , Balfour‐Lynn I.M. , Bush A. 
Published: January 2003

AbstractThe information obtained from a simple submaximal test (the 3‐min step test) was compared with that from a maximal cycle ergometry study, in a group of children with CF with relatively mild abnormalities of lung function (FEV1 > 50% predicted). Nineteen subjects with CF undertook both exercise tests on the same day. Measurements included heart rate (HR), oxygen saturations (SaO2), visual analogue score of perceived breathlessness (VAS), 15‐count breathlessness score (15c), and peak oxygen consumption (VO2). There were significant differences in the median changes in HR and VAS during the cycle test compared to the step test, 78 vs. 46 beats per minute (P < 0.05) and 51 mm vs. 42 mm (P < 0.05), respectively. There were no differences between median changes in 15c and SaO2, but 3 subjects had significant desaturations (>4%) during the cycle test only. Significant exercise desaturations may occur in mild CF lung disease and will not be detected by a 3‐min step test. The 15c did not discriminate between a maximal and a submaximal test, and was less useful than VAS. Important information may be missed by the step test which is detected by more complex exercise tests. Pediatr Pulmonol. 2003; 35:108–113. © 2003 Wiley‐Liss, Inc.
Antimicrobial susceptibility profile of molecular typed cystic fibrosis Stenotrophomonas maltophilia isolates and differences with noncystic fibrosis isolates
Authors: Cantón Rafael , Valdezate Sylvia , Vindel Ana , Sánchez Del Saz Begoña , Maíz Luis , Baquero Fernando 
Published: January 2003

AbstractMultiresistance in Stenotrophomonas maltophilia limits the effectiveness of antimicrobial therapy for infections due to this organism. It can be of special concern in cystic fibrosis (CF) patients due to frequent antimicrobial administration. The in vitro activity of 41 antimicrobial agents against 76 epidemiologically defined CF S. maltophilia isolates by pulsed‐field‐gel electrophoresis (PFGE) technique under XbaI and SpeI restriction was compared with that obtained with 51 non‐CF strains recovered from respiratory sources. Minimal inhibitory concentrations (MICs) were determined with the standard National Committee for Clinical Laboratory Standards agar dilution technique, but with 24‐hr incubation. Forty‐seven different PFGE profiles were observed within 76 S. maltophilia CF isolates. Minocycline (resistance rate, 0%; MIC90, 1 μg/ml), doxycycline (6.4%; 8 μg/ml), trovafloxacin (4.2%; 2 μg/ml), moxifloxacin (6.3%; 2 μg/ml), clinafloxacin (6.3%; 2 g/ml), and moxalactam (17.0%; 64 g/ml) displayed low resistance rates. On the contrary, resistance rates were higher with ceftazidime (70.0%; 256 μg/ml), cefepime (83.0%; 128 μg/ml), piperacillin (87.2%; >1,024 μg/ml), ticarcillin (87.2%; >512 μg/ml), and aztreonam (95.7%; >1,024 μg/ml). Clavulanate reverted resistance to ticarcillin and aztreonam in 40.4% and 31.7% of strains, respectively. Aminoglycosides displayed reduced activities with susceptibility rates lower than 20% and MIC90 higher than 128 μg/ml. With the exception of trimethoprim‐sulfamethoxazole (25.4 vs. 31.3%), CF isolates were more resistant than non‐CF isolates. Remarkably, resistance was enhanced in S. maltophilia isolates persistently recovered in chronically colonized patients. Susceptibility analysis demonstrated higher resistance rates among CF S. maltophilia isolates when compared with respiratory isolates from non‐CF patients. Moreover, persistently recovered CF S. maltophilia isolates were more resistant than sporadic non‐CF isolates. Pediatr Pulmonol. 2003; 35:99–107. © 2003 Wiley‐Liss, Inc.