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Reaction-diffusion systems have been primary tools for studying pattern formation. A skew-gradient system is well known to encompass a class of activator-inhibitor type reaction-diffusion systems that exhibit localized patterns such as fronts and pulses. While there is a substantial literature for the case of a linear inhibitor equation, the study of nonlinear inhibitor effect is still limited. To fill this research gap, we investigate standing pulse solutions to a skew-gradient system in which both activator and inhibitor reaction terms inherit nonlinear structures. Using a variational approach that involves several nonlocal terms, we establish the existence of standing pulse solutions with a sign change. In addition, we explore some qualitative properties of the standing pulse solutions.

This study investigates the thermal and electrical stabilities of superconducting coils encapsulated with an epoxy/acid-treated carbon nanotube (CNT) composite through cool-down, over-current, and repetitive-cooling tests. Carboxylic acid groups were successfully attached to CNT surfaces by acid treatment, which facilitated uniform CNT dispersion within the epoxy resin, forming preferential paths for heat conduction. The coil encapsulated with the epoxy/acid-treated CNT composite showed a fast cooling rate in a bath of liquid nitrogen (LN2) and high endurance under over-current conditions. This contrasts with its counterpart encapsulated with untreated CNTs, because heat was easily dissipated in the epoxy/acid-treated CNT composite owing to its higher thermal conductivity. Moreover, the difference in the thermal expansion coefficients of the epoxy and the superconducting tape decreased. Therefore, using an epoxy composite containing acid-treated CNTs is recommended for developing a mechanically dense superconducting coil with enhanced thermal and electrical stabilities.

This paper describes the design and development of a context-aware fleet management system (CFMS) prototype for real-time accident handling in logistics using a design science approach. One of the most important decisions in fleet management is the optimization of vehicle scheduling during an accident, such as a vehicle breakdown and mechanical failure during delivery. The schedule planner has to assign another vehicle to take over the task; thus, accident handling needs the reassignment or re-scheduling of vehicles. The large number of available vehicles for reassignment and numerous trips in a day make rescheduling complicated and difficult to resolve. In this paper, we propose a CFMS integrated with global positioning system (GPS) for real-time vehicle positioning and eSeal enabled by the RFID technology, to help human planners with rescheduling. A CFMS prototype was built and evaluated in a real-world setting. The system prototype was satisfactory during evaluation. The system was found to be more effective by its potential users and field logistics experts in aiding real-time accident handling in logistics. The design science approach used to develop the prototype could form a basis for further research.

This paper aims to use soft systems methodology (SSM) to identify management support system opportunities for managing energy and utility usage in textile manufacturing processes. It presents an approach based on SSM to analyze the complex situation of developing an effective energy and utility management support system (EUMSS). This involves the identification of the scope of the system and user requirements, conceptual modeling of complex problem situations, identification of actors and decision processes, and information-needs modeling. The current study pioneers the examination of the application of SSM to the development of a novel EUMSS and contributes to the body of information systems knowledge in the context of EUMSS design. There appears to be limited academic research in the field of energy and utility system development and, in particular, in the area of EUMSS design, and none in the area of the application of SSM to EUMSS design. In addition, the modeling process could be beneficial if EUMSS design ideas could be widely shared and discussed. The identified scope and system requirements can serve as a guideline for designing and developing an effective EUMSS for textile processing.

In this paper, we study global positive C 4 solutions of the geometrically interesting equation: Δ 2 u + u − q = 0 with q > 0 in R 3 . We will establish several existence and non-existence theorems, including the classification result for q = 7 with exactly linear growth condition.

It is shown that a non-generic bifurcation of non-linear normal modes may occur if the ratio of linear natural frequencies is near r-to-one, r = 1 , 3 , 5 , … . Non-generic bifurcations are explicitly obtained in the systems having certain symmetry, as observed frequently in literatures. It is found that there are two kinds of non-generic bifurcations, super-critical and sub-critical. The normal mode generated by the former kind is extended to large amplitude, but that by the latter kind is limited to small amplitude which depends on the difference between two linear natural frequencies and disappears when two frequencies are equal. Since a non-generic bifurcation is not generic, it is expected generically that if a system having a non-generic bifurcation is perturbed then the non-generic bifurcation disappears, and generic bifurcation appears in the perturbed system. Examples are given to verify the change in bifurcations and to obtain the stability behavior of normal modes. It is found that if a system having a super-critical non-generic bifurcation is perturbed, then two new normal modes are generated, one is stable, but the other unstable, implying a saddle-node bifurcation. If the system having a sub-critical non-generic bifurcation is perturbed, then no new normal mode is generated, but there is an interval of instability on a normal mode, implying two saddle-node bifurcations on the mode. Application of this study is discussed.

This paper consists of two parts. In the first part, we proved the global existence of weak solutions of a strongly coupled quasilinear parabolic system in Rn using weak compactness method. In the second part, we considered the electrochemistry model studied in Choi and Lui (J. Differential Equations 116 (1995) 306) where the Poisson equation governing the electric potential is replaced by a local electro-neutrality condition. In one space dimension, the equations for the model is of the form considered in the first part of this paper except that the coefficient matrix is discontinuous at places where all the charged ions vanish. We approximate the equations by nicer operators and pass to the limit to obtain global existence of weak solutions. The non-negativity of weak solutions and L2-stability of the steady-state solutions are also shown under additional hypotheses.

This paper studies the existence of solutions of a nonlinear elliptic system usually called the generalized Gierer–Meinhardt equations. This type of system originally arose in studies of pattern-formation in biology, and has interesting and challenging mathematical properties, especially with Dirichlet boundary conditions when the nonlinear terms become singular near the boundary. We study the existence of solutions in the classical case of Gierer–Meinhardt, when the activator-inhibitor model has different sources.

The standard approaches for the preclinical development of chronically administered drugs also apply to most respiratory drugs. Modifications from the standard preclinical development plan, however, may be necessary if the drug is administered intranasally or by inhalation. Administration by these routes may result in airway toxicity and the intended patient population is often particularly susceptible. Current and former representatives of the Division of Pulmonary Drug Products (CDER, U.S. FDA) present this article to describe general principles of preclinical development for respiratory drug indications. The article addresses drugs intended for administration by the intranasal or inhalation routes. The article describes the types of studies recommended, considers the initial human dose, and discusses dose-escalation strategies in clinical trials. Other areas of special concern with intranasal or inhalation administration include immunotoxicity, reproductive toxicity, types of dosing apparatus, excipients and extractables, and formulation changes. The approaches described in this article are intended as general information and should be adapted to the scientific considerations and circumstances of a particular drug under development.

Thin films of zinc oxide, cadmium oxide, and their compounds have been deposited by the sol-gel process. The ZnO and CdO films are found to have different crystallographic structures and their compounds are found to be simple mixtures of the two different crystallographic strutures for the constituent materials. The electrical resistivity of the compounds, ZnxCd1−xO thin films decreases as the composition x decreases, so that pure CdO thin films have the lowest electrical resistivity of 3×10−3 Ωcm. Although the optical transmittance and bandgap of the ZnxCd1−xO films also decrease as the value of x decreases, all the films prepared in this study have a fairly high transmittance reproducibly in the visible spectral range at room temperature. The electrical resistivity of the films is found to have significant dependence on the post-deposition annealing environments. This dependence is more pronounced for the films which contain higher percentages of Zn among all the ZnxCd1−xO films prepared in this study. The dependence of the electrical resistivity on the aluminium impurity concentration in the ZnxCd1−xO films is also examined.

The present study was designed to investigate the modulatory effects of blockade of spinal histamine receptors on antinociception induced by spinally administered morphine, beta-endorphin and U50, 488H. The effects of intrathecal (i.t.) injections with cyproheptadine (a histamine-1 (H1) receptor antagonist), ranitidine (an H2 receptor antagonist), or thioperamide (an H3 receptor antagonist) injected i.t., on the antinociception induced by morphine, beta-endorphin or trans-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl) cyclohexyl] benzeocetamide (U50, 488H) injected intrathecally (i.t.) were studied. The antinociception was assayed using the tail-flick test. The i.t. injection of cyproheptadine (20 micrograms), ranitidine (20 micrograms), or thioperamide (20 micrograms) alone did not produce any antinociceptive effect. i.t. pretreatment with cyproheptadine attenuated the inhibition of the tail-flick response induced by i.t. administered morphine or beta-endorphin, but not U50, 488H. In addition, i.t. pretreatment with ranitidine attenuated the inhibition of the tail-flick response induced by i.t. administered morphine, beta-endorphin, or U50, 488H. Furthermore, the i.t. pretreatment with thioperamide attenuated the inhibition of the tail-flick response induced by beta-endorphin or U50, 488H, but not morphine, administered i.t. Our results indicate that spinal H1 receptors may be involved in the production of antinociception induced by spinally applied morphine or beta-endorphin- but not U50, 488H. Spinal H2 receptors appear to be involved in spinally administered morphine-, beta-endorphin- and U50, 488H-induced antinociception. Supraspinal histamine H3 receptors may be involved in the production of antinociception induced by supraspinally applied beta-endorphin or U50, 488H, but not morphine.

We propose to develop a mathematical model for the electrokinetic remediation of contaminated soil. We assume that the contaminants are mostly heavy metals, water is in excess, the dissociation-association of water into hydrogen and hydroxyl ions is rapid, and that electroosmosis is insignificant when compared to electromigration as a transport mechanism. Steady-state solutions for the model are derived and results of the numerical simulations are given to show that heavy metals in the soil are removed by this method in the long run.

Various doses of 3-isobutyl-1-methylxanthine (IBMX), a cAMP phosphodiesterase inhibitor, injected intrathecally (i.t.) or intracerebroventricularly (i.c.v.) alone did not show any antinociceptive effect. IBMX (0.01 to 1 ng) pretreatment i.t. for 10 min dose-dependently attenuated the inhibition of the tail-flick response induced by i.c.v. administered morphine (2 micrograms), beta-endorphin (1 microgram), and U50, 488H (trans-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl) cyclohexyl] benzeocetamide), 60 micrograms. However, pretreatment with IBMX i.c.v. did not affect the inhibition of the tail-flick response induced by morphine, beta-endorphin, and U50, 488H administered i.c.v. Neither i.c.v. nor i.t. pretreatment with IBMX attenuated the inhibition of the tail-flick response induced by D-Pen2-D-Pen5-enkephalin (DPDPE; 10 micrograms) administered i.c.v. Our results suggest that spinal but not supraspinal cAMP phosphodiesterases are involved in mediating antinociception induced by morphine, beta-endorphin and U50, 488H administered supraspinally. However, neither spinal nor supraspinal cAMP phosphodiesterase is involved in mediating antinociception induced by DPDPE administered supraspinally.

The antinociception induced by morphine but not beta-endorphin, D-Pen2-D-Pen5-enkephalin (DPDPE), or U50, 488H (trans-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl) cyclohexyl] benzeocetamide) administered intracerebroventricularly (i.c.v.) has been previously demonstrated to be mediated by the N-Methyl-D-Aspartic Acid (NMDA) receptor. The present study was designed to determine if non-NMDA receptors are involved in opioid-induced antinociception. Antinociception was assessed by the tail-flick test in male ICR mice. Various doses of CNQX (6-Cyano-7-nitroquinoxaline-2,3-dione), a competitive non-NMDA receptor antagonist, (0.001 to 0.5 microgram) injected intracerebroventricularly (i.c.v.) alone did not show any antinociceptive effect. CNQX (0.01 to 1 micrograms, i.c.v.) dose-dependently attenuated the inhibition of the tail-flick response induced by morphine (1 microgram). However, inhibition of the tail-flick response induced by i.c.v. administered beta-endorphin (1 microgram), DPDPE (10 micrograms), or U50, 488H was not affected by i.c.v. administered CNQX. It is concluded that non-NMDA receptors are involved in i.c.v. morphine-induced antinociception. However, non-NMDA receptors are not involved in i.c.v. administered beta-endorphin-, DPDPE-, and U50, 488H-induced antinociception at the supraspinal level.

Exact solutions of transport in a binary electrolyte are derived for two cases. The first case is steady-state one-dimensional transport with one reacting ion and one inert ion. The second case is an unsteady-state one-dimensional concentration cell. Numerical examples are given to illustrate the simplicity in the application of the solutions.

A hybrid apparatus consisting of a movable emulsion target and a magnetic spectrometer was used in a fixed target Fermilab Tevatron experiment to study the production of heavy quarks by high-energy hadron beams. High-resolution silicon microstrip detectors were used for precise tracking in the dense particle environment. Details of the experimental apparatus, including the data acquisition system, are described.

Background There is controversy regarding palliative chemotherapy for large cell neuroendocrine carcinoma (LCNEC). We evaluated whether advanced LCNEC should be treated similarly as small-cell lung cancer (SCLC) or non-small-cell lung cancer (NSCLC). Methods The clinical reports and tumor specimens of 45 consecutive patients who were diagnosed with advanced LCNEC were reviewed. They were divided into SCLC (n = 11) and NSCLC regimen groups (n = 34) according to first-line chemotherapeutic regimens. Results Most patients were male (96%) and smokers (93%) with a median age of 64 years. Neuroendocrine differentiation was established in 42 (93%) tumors by immunohistochemical analyses. Regarding the efficacy of first-line chemotherapy in the SCLC and NSCLC regimen group, the response rates were 72.7% and 50% (P = 0.19), and the median progression-free survival times were 6.1 and 4.9 months (P = 0.41), respectively. The difference in overall survival between the two treatment groups was 7.3 months (16.5 versus 9.2 months, P = 0.10). There was also a contrasting difference in the type and efficacy of salvage chemotherapeutic regimens between the two groups: salvage regimens with irinotecan, platinum, or taxanes were commonly used with relatively high objective responses in the SCLC regimen group, whereas frequently used agents in the NSCLC regimen group such as pemetrexed, gefitinib, or erlotinib were associated with no objective response. Conclusions Regarding palliative chemotherapy, advanced LCNEC should be treated similarly as SCLC rather than NSCLC.