Showing papers by "Applied Science Private University published in 1998"

An artificial neural network approach to rainfall-runoff modelling

Abstract: This paper provides a discussion of the development and application of Artificial Neural Networks (ANNs) to flow forecasting in two flood-prone UK catchments using real hydrometric data. Given relatively brief calibration data sets it was possible to construct robust models of 15-min flows with six hour lead times for the Rivers Amber and Mole. Comparisons were made between the performance of the ANN and those of conventional flood forecasting systems. The results obtained for validation forecasts were of comparable quality to those obtained from operational systems for the River Amber. The ability of the ANN to cope with missing data and to “learn” from the event currently being forecast in real time makes it an appealing alternative to conventional lumped or semi-distributed flood forecasting models. However, further research is required to determine the optimum ANN training period for a given catchment, season and hydrological contexts.

Nontypeable Haemophilus influenzae: Pathogenesis and Prevention

Abstract: In this paper, we describe the ability of nontypeable Haemophilus influenzae (NTHi) to coexist with the human host and the devastating results associated with disruption of the delicate state of balanced pathogenesis, resulting in both acute and chronic respiratory tract infections. It has been seen that the strains of NTHi causing disease show a marked genetic and phenotypic diversity but that changes in the lipooligosaccharide (LOS) and protein size and antigenicity in chronically infected individuals indicate that individual strains of NTHi can remain and adapt themselves to avoid expulsion from their infective niche. The lack of reliance of NTHi on a single mechanism of attachment and its ability to interact with the host with rapid responses to its environment confirmed the success of this organism as both a colonizer and a pathogen. In vitro experiments on cell and organ cultures, combined with otitis media and pulmonary models in chinchillas, rats, and mice, have allowed investigations into individual interactions between NTHi and the mammalian host. The host-organism interaction appears to be a two-way process, with NTHi using cell surface structures to directly interact with the mammalian host and using secreted proteins and LOS to change the mammalian host in order to pave the way for colonization and invasion. Many experiments have also noted that immune system evasion through antigenic variation, secretion of enzymes and epithelial cell invasion allowed NTHi to survive for longer periods despite a specific immune response being mounted to infection. Several outer membrane proteins and LOS derivatives are discussed in relation to their efficacy in preventing pulmonary infections and otitis media in animals. General host responses with respect to age, genetic makeup, and vaccine delivery routes are considered, and a mucosal vaccine strategy is suggested.

Differential Misclassification and the Assessment of Gene-Environment Interactions in Case-Control Studies

Abstract: In case-control studies of interactions between genetic and environmental exposures, differential misclassification of the environmental exposure with respect to disease status can introduce spurious heterogeneity of the stratum-specific odds ratios. In this paper, the authors identify conditions under which differential misclassification does not introduce bias in the interaction parameter when no multiplicative interaction is present, and it biases the interaction parameter toward the null value when a multiplicative interaction is present. The conditions are that (i) conditional on potential confounders, the environmental exposure is independent of the genotype among the controls, and (ii) misclassification of the environmental exposure is nondifferential with respect to the genotype. These conditions can be tested from the misclassified data in the control group, since a test of the independence of the genotype and the misclassified environmental exposure among the controls is a test of the joint hypothesis that conditions (i) and (ii) are both true. Therefore, the authors propose a two-step test for interaction which first tests conditions (i) and (ii) and then goes on to test for interaction, provided the first step hypothesis is not rejected. A summary test procedure to test for gene-environment interactions in the presence of misclassification, based on both a conventional test for interaction and the two-step test, is recommended, and is illustrated with data from a case-control study of the role of diet as a modifier of the association between a metabolic polymorphism and lung cancer.

Crystal plasticity forming limit diagram analysis of rolled aluminum sheets

Abstract: Numerical simulations of forming limit diagrams (FLDs) are performed based on a rate-sensitive polycrystal plasticity model together with the Marciniak-Kuczynski (M-K) approach Sheet necking is initiated from an initial imperfection in terms of a narrow band The deformations inside and outside the band are assumed to be homogeneous, and conditions of compatibility and equilibrium are enforced across the band interfaces Thus, the polycrystal model needs only to be applied to two polycrystalline aggregates, one inside and one outside the band Each grain is modeled as an fcc crystal with 12 distinct slip systems The response of an aggregate comprised of many grains is based on an elastic-viscoplastic Taylor-type polycrystal model With this formulation, the effects of initial imperfection intensity and orientation, initial distribution of grain orientations, crystal elasticity, strain-rate sensitivity, single slip hardening, and latent hardening on the FLD can be assessed The predicted FLDs are compared with experimental data for the following rolled aluminum alloy sheets: AA5754-0-A, AA5754-0-B, AA6111-T4-A, AA6111-T4-C, and AA6111-T4-D

Potential of a Novel Protein, OMP26, from Nontypeable Haemophilus influenzae To Enhance Pulmonary Clearance in a Rat Model

Abstract: A major outer membrane protein band of approximately 25 to 27 kDa is commonly observed in strains of Haemophilus influenzae. This study has investigated the potential of a 26-kDa protein (OMP26) from nontypeable H. influenzae (NTHI) as a vaccine candidate. OMP26 was used to immunize rats via intestinal Peyer's patches, followed by an intratracheal boost. Immunization was found to significantly enhance bacterial clearance following pulmonary challenge with both the homologous NTHI strain and a different NTHI strain. Significant levels of anti-OMP26 were found in the serum and bronchoalveolar lavage from immunized rats, and isotypes of immunoglobulin G (IgG) were also measured in serum. Analysis of IgG isotypes present in serum following OMP26-immunization suggest that predominantly a T-helper 1-type response was induced. The OMP26 protein was amino-terminally sequenced and found to have no homology with the P5 of H. influenzae type b P5 or the fimbrin protein of NTHI, both can migrate upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis at similar molecular masses but OMP26 has 100% homology with a segment of the H. influenzae Rd genome. The results of this study suggest that OMP26 may be a suitable vaccine candidate against NTHI infection and warrants continued investigation and characterization.

Secondary structure and molecular analysis of interstrain variability in the P5 outer-membrane protein of non-typable Haemophilus influenzae isolated from diverse anatomical sites

Abstract: Summary The sequence of the non-typable Haemophilus influenzae (NTHi) P5 outer-membrane protein from a range of clinical isolates is presented and represents the first analysis of the heterogeneity in P5 from NTHi isolates from diverse anatomical sites. the basis of the previously observed inter-strain variation in the electrophoretic mobility is attributed to heterogeneity in three hypervariable regions. Alignment of the P5 sequences identified regions which are highly conserved and align with the transmembrane region predicted for the homologous Escherichia coli protein, OmpA. Variable regions correspond to surface-exposed loops, of which the first loop falls into subclasses. However, these subclasses fail to correlate with anatomical predisposition. Although P5 has been proposed as a fimbrial protein composed of coiled coils, both structural analysis by circular dichroism of purified P5 and computer analysis of the multiply aligned sequences predict a high proportion of β strand with no evidence of coiled coil structure. A detailed model of P5 is presented.

The quality and coping patterns of women's decision‐making regarding breast cancer surgery

Abstract: This study addressed issues regarding the decision-making process used by women who had mastectomy as their surgical treatment for breast cancer. The seven criteria for quality decision-making and the conflict model proposed by Janis and Mann (1977) were used as the study's conceptual framework along with the notion by Simon (1957) of 'bounded rationality'. Four coping patterns emerged: vigilance (actively searches for information and advice), satisficing (being satisfied, chooses first solution that meets the desired objectives), complacency (accepts advice without questions or fully comprehending), and defensive avoidance (rationalises and avoids discussion and consideration of the problem). The participants primarily left the decision for surgical treatment of breast cancer to their surgeons using satisficing, complacency and defensive avoidance. When the option of lumpectomy was offered to some of the participants (34%), they rejected this treatment alternative using the coping patterns of satisfying and defensive avoidance. Those women who were not offered lumpectomy (66%) did not seek a rationale for not being given this alternative. The findings indicated that the women's decision-making process was halted in Stage 2 of the criteria for quality decision-making actively searched for and viewed a number of alternatives. The study's findings are discussed in relation to improving the quality of the decision-making process for women regarding their breast cancer surgical treatment.

Energy analysis of the steel making industry

Abstract: Steel making is an energy intensive industry. This work presents and identifies heat losses of the main components of this industry in Jordan. The heat losses are considerable and range from 17 to 36% of the total energy input. Some heat losses are considered to be recoverable, especially in the furnace and the crucible and mould. Specific energy consumption was found to be 6·0 MJ per ton of steel for the Jordanian steel industry. © 1998 John Wiley & Sons, Ltd.

A Six Sensor Array of Coated‐Wire Electrodes for Use in a Portable Flow Injection Analyzer

Abstract: An array of five photo-cured epoxydiacrylate membrane based coated-wire electrodes and a Ag/AgCl wire electrode used as a chloride sensor were all used simultaneously in a previously reported multielectrode flow cell and in a portable flow injection analyzer [1]. Photo-cured coated-wire electrodes for ammonium, calcium, hydrogen (pH), nitrate and potassium and Ag/AgCl wire based chloride electrode were developed for remote-site monitoring. The photo-cured membranes prepared exhibited strong adhesion to the metal substrate and showed improved mechanical strength compared to poly(vinyl chloride) based membranes. Each sensor in the present electrode-array exhibited near-Nernstian response over a log-linear range of between 0.1 mM and 10 mM with detection limits of 0.01 mM in the flow injection potentiometric mode. The flow injection cell was capable of determining the respective ions in various water samples and the results were in good agreement with comparative analytical methods.

Outer-membrane antigen expression by Moraxella (Branhamella) catarrhalis influences pulmonary clearance

Abstract: Moraxella (Branhamella) catarrhalis is a common respiratory tract pathogen in man. The bacterium shows a strong tendency to form aggregates in vitro. A variant strain of M. catarrhalis that showed a reduced tendency to form aggregates was selected by successive in-vitro passage in broth culture from which aggregates had settled. The non-clumping variant strain showed alteration in expression of outer-membrane antigens, including the HMW-OMP, an outer-membrane protein of c. 200 kDa, outer-membrane protein CD and lipo-oligosaccharide. A mouse model for pulmonary challenge with M. catarrhalis revealed significant differences in the rate of clearance of the isogenic variant strains from the lung. The parent strain caused enhanced recruitment of neutrophils to the lung and more rapid clearance of bacteria from the lungs in comparison to the non-clumping variant. It is concluded that alteration of expression of surface molecules by M. catarrhalis has a significant impact in an in-vivo model of pulmonary clearance.

Application of Multicriteria Decision Aid to Rank the Jordan-Yarmouk Basin Co-riparians According to the Helsinki and ILC Rules

Abstract: The Jordan River system, shared by Jordan, Israel, the Palestinians in the occupied territories, Syria, and Lebanon, is a major issue in Middle East politics. This paper identifies the water resources of the system, outlines historical development plans, and presents the relevant legal riparian issues and practices related to the basin. The descriptive analysis concludes that the application of the Helsinki and ILC rules separately is not suitable to a region which is in conflict on every issue. To assist in addressing the problem based on recognized water rights and water sharing, mathematical tools need to be used as these tools may help to help solve the problem based on recognized water rights and water sharing. The Multicriteria Decision Aid (MCDA) method of PROMETHEE was applied to rank the co-riparians. The results of relative ranking indicate that Jordan and the Palestinians in the occupied territories ranked high in this analysis (compared to Israel, Syria, and Lebanon). Sensitivity anal...

Predictive control of aluminum electrolytic cells using neural networks

Abstract: In this work, neural networks are built and trained to be used in a predictive control scheme for the aluminum electrolytic cell. An efficient control of the cell requires the knowledge of predicted future values of the decision variables in order to enable the standard (nonpredictive) control logic to take anticipated actions to prevent the anode effect, a destabilizing event occurring during cell operation. The networks are first trained on data obtained from a computer simulator of the cell prior to undergoing further on-line learning. Trained to predict the cell resistance and the resistance’s trend indicators, the networks are applied to the control of cells in different cell states, with a view to preventing anode effects, the latter being deliberately induced by reducing the alumina feed rate or reducing the feeding frequency and duration. Results show that, with neural-predictive control, anode effects can be avoided, which should result in increased thermal stability, decreased power consumption, and reduced fluoride emissions. Further, the on-line learning capacity of the networks offers a good perspective for their application to other complex industrial processes as well.

Characteristics of the immunological response in the clearance of non-typeable Haemophilus influenzae from the lung

Abstract: Characteristics of the immunological response in the clearance of non-typeable Haemophilus influenzae from the lung

Kinetics of inflammatory cytokines in the clearance of non-typeable Haemophilus influenzae from the lung

Abstract: Top of pageAbstract Levels of the pro-inflammatory cytokines TNF- and IFN- were measured from the time of infection to the time of complete clearance of non-typeable Haemophilus influenzae (NTHi) from the lung in immune and non-immune rats. Mucosal immunization facilitated production of significant levels of TNF- as early as 30 min post-pulmonary challenge with NTHi in immune animals. Following the peak at 2 h, rapid decline of TNF- levels occurred from the alveolar spaces. Levels of TNF- in non-immunized animals increased at a slower rate, peaked at a lower concentration and were slower to decline. The significantly larger number of macrophages seen in the immune animals at 1 h after bacterial challenge could partially account for the higher levels of TNF-. Interferon- was not detected in immune or non-immune rats at any time point before NTHi clearance after pulmonary challenge. Study of the kinetics of TNF- release demonstrates that immunized animals control the release of pro-inflammatory cytokines more effectively than non-immunized animals for enhanced clearance of bacterial infection from the lungs. Keywords: IFN-, lung, macrophage, mucosal, non-typeable Haemophilus influenzae , TNF-, vaccine

Potentials of wind energy development for water desalination in Jordan

Abstract: The potential of the development of water desalination using wind energy in Jordan was studied. Eleven wind solar sites were considered. The results show that these sites can be divided, in terms of the yearly total amount of desalinated water, into three categories. One is considered favourable, which includes Ras Muneef, Mafraq, and Aqaba. Their water production adds up to about 75% of all water produced from all 11 sites combined. Others are considered to be promising (about 24% in total), which include H-5, Irbid, and Ma'an. The rest of sites considered are found to be very poor, which include H-4, Amman, Queen Alia Airport, Shoubak, and Deiralla, with traces of water produced (less than 1%).

A field-portable gas analyzer with an array of six semiconductor sensors. Part 2: Identification of beer samples using artificial neural networks

Abstract: A method is described based on a new portable, multisensor gas analyzer applying an artificial neural network to discriminate between six beer brands. The gas analyzer as previously reported employed six different tin-oxide semiconductor sensors, and the detection method was based on headspace analysis of the vapor above beer samples. The artificial neural network (ANN) used in this study was a three-layer network, standard back-propagation algorithm. The network was trained with the use of 553 cycles in 7.11 min at a learning rate of 1.0 and training tolerance of 0.1. A Macintosh PowerBook 1400cs with PowerPC™ 603e at 133-MHz clock frequency and 128-kilobyte Level Two write-through cache memory on a processor system bus was used to train the ANN. This study indicates that the portable, multisensor analyzer is able to discriminate among beers and thus may be used to monitor beer product quality in industrial processes, having the advantage of portability and low cost for use in sites remote from chemical laboratories. Further applications in food technology are in the testing of foods and beverages for quality and shelf life. © 1998 John Wiley & Sons, Inc. Field Analyt Chem Technol 2: 145-153, 1998.

Conservation and management in Jervis Bay, Australia

Abstract: The growth of the human population and the impact of this upon the natural environment is there for all to see. Little wonder that public concern for the environment has increased in recent decades. Such preoccupations have resulted in a corresponding increase in the declaration of new areas as national parks, reserves and other protected areas. In Australia the declaration of such areas meets an important need to preserve both the natural heritage and the human and cultural heritage. This paper describes the processes and policy implications of the declaration of national parks, marine parks, and recreational areas in Australia. Jervis Bay on the New South Wales (NSW) coast is used as a case study to document these processes and to evaluate the policy implications. After an initial discussion on conservation and management a vision statement for the bay is analysed in terms of its various dimensions. In the implementation of the vision, various approaches are canvassed. An integrated, total catchment management system is proposed. © 1998 John Wiley & Sons, Ltd.

The Geometric Origin of Asymmetric Small Angle Neutron Scattering from an Elastically Bent Double Crystal Diffractometer

Abstract: We have investigated the Small Angle Neutron Scattering (SANS) from a Double Crystal Diffractometer (DCD) in the (1, -1) setting using a focusing Si monochromator crystal in the symmetric (111) case and a defocusing analyser Si crystal in a completely asymmetric (111) case. We have found SANS data from porous glassy carbon and Silca spheres are asymmetric about the Bragg Peak centre. We attribute this observation to a combination of factors, particularly geometrical effects, related to the angle of acceptance χ into the analyser crystal when a SANS sample is positioned between the crystal pair. A simple procedure for SANS data correction is outlined and shown to be effective in this case.