1,035 research outputs found
ALPS: A Linear Program Solver
ALPS is a computer program which can be used to solve general linear program (optimization) problems. ALPS was designed for those who have minimal linear programming (LP) knowledge and features a menu-driven scheme to guide the user through the process of creating and solving LP formulations. Once created, the problems can be edited and stored in standard DOS ASCII files to provide portability to various word processors or even other linear programming packages. Unlike many math-oriented LP solvers, ALPS contains an LP parser that reads through the LP formulation and reports several types of errors to the user. ALPS provides a large amount of solution data which is often useful in problem solving. In addition to pure linear programs, ALPS can solve for integer, mixed integer, and binary type problems. Pure linear programs are solved with the revised simplex method. Integer or mixed integer programs are solved initially with the revised simplex, and the completed using the branch-and-bound technique. Binary programs are solved with the method of implicit enumeration. This manual describes how to use ALPS to create, edit, and solve linear programming problems. Instructions for installing ALPS on a PC compatible computer are included in the appendices along with a general introduction to linear programming. A programmers guide is also included for assistance in modifying and maintaining the program
Home- and Car-Based Rules in Foster Care Settings to Reduce Exposure to Secondhand Smoke: Before and after Romanian National Clean Air Legislation.
Background: To evaluate changes in smoke free rules in the foster care system after the implementation of the Romanian national clean air law. Methods: A repeated cross-sectional, self-administered questionnaire among foster care employees (n = 599) was conducted in 58 foster care homes during 2014 (n = 295) and 51 homes during 2016 (n = 304). We estimated the absolute difference in the proportion of employees who stated that smoke free rules existed before and after national clean air legislation. Results: There was an absolute increase in 4 of 5 smoke free measures after the law: bans on non-cigarette tobacco products (n = 169 to 206, +10.6%), non-smoking on premises for adults (n = 142 to 202, +18.3%), and for children (n = 201 to 239, +10.3%), and no smoking in cars to transport children (n = 194 to 227, +9%). There was a significant increase in the perception of outdoor bans that prohibit employees from smoking on foster care home premises (AOR 2.24, 95% CI 1.14(-)4.38). The increase in the perception of indoor smoking bans did not change. Conclusion: The national law may have had a spillover influence by strengthening smoke free rules in unregulated spaces. Nonetheless, foster care home rules could be further enhanced, particularly in cars that transport children
Estimating the Rotation Rate in the Vacuolar Proton-ATPase in Native Yeast Vacuolar Membranes
The rate of rotation of the rotor of the yeast vacuolar proton-ATPase (V-ATPase), relative to the stator or the steady parts of enzyme, is estimated in native vacuolar membrane vesicles of Saccharomyces cerevisiae under standardised conditions. Membrane vesicles are spontaneously formed after exposing purified yeast vacuoles to osmotic shock. The fraction of the total ATPase activity originating from V-ATPase is determined using the potent and specific inhibi-tor of the enzyme, concanamycin A. Inorganic phosphate liberated from ATP in the vacuolar membrane vesicle system, during 10 min of ATPase activity at 20 °C, is assayed spectrophotometrically for different concanamycin A concentrations. A fit to the quadratic binding equation, assuming a single concanamycin A binding site on a monomeric V-ATPase (our data is incompatible with models assuming more binding sites) to the inhibitor titration curve determines the concentration of the enzyme. Combining it with the known rotation:ATP stoichiometry of V-ATPase and the assayed concentration of inorganic phosphate liberated by V-ATPase leads to an average rate of ~9.53 Hz of the 360 degrees rotation, which, according to the time-dependence of the activity, extrapolates to ~14.14 Hz for the beginning of the reaction. These are low limit estimates. To our knowledge this is the first report of the rotation rate in a V-ATPase that is not subjected to genetic or chemical modification and it is not fixed on a solid support, instead it is functioning in its native membrane environment
Protective Intestinal Effects of Pituitary Adenylate Cyclase Activating Polypeptide
Pituitary adenylate cyclase activating polypeptide (PACAP) is an
endogenous neuropeptide widely distributed throughout the body, including the
gastrointestinal tract. Several effects have been described in human and animal
intestines. Among others, PACAP infl uences secretion of intestinal glands, blood
fl ow, and smooth muscle contraction. PACAP is a well-known cytoprotective peptide
with strong anti-apoptotic, anti-infl ammatory, and antioxidant effects. The
present review gives an overview of the intestinal protective actions of this neuropeptide.
Exogenous PACAP treatment was protective in a rat model of small bowel
autotransplantation. Radioimmunoassay (RIA) analysis of the intestinal tissue showed that endogenous PACAP levels gradually decreased with longer-lasting
ischemic periods, prevented by PACAP addition. PACAP counteracted deleterious
effects of ischemia on oxidative stress markers and cytokines. Another series of
experiments investigated the role of endogenous PACAP in intestines in PACAP
knockout (KO) mice. Warm ischemia–reperfusion injury and cold preservation models
showed that the lack of PACAP caused a higher vulnerability against ischemic
periods. Changes were more severe in PACAP KO mice at all examined time points.
This fi nding was supported by increased levels of oxidative stress markers and
decreased expression of antioxidant molecules. PACAP was proven to be protective
not only in ischemic but also in infl ammatory bowel diseases. A recent study showed
that PACAP treatment prolonged survival of Toxoplasma gondii infected mice suffering
from acute ileitis and was able to reduce the ileal expression of proinfl ammatory
cytokines. We completed the present review with recent clinical results obtained
in patients suffering from infl ammatory bowel diseases. It was found that PACAP
levels were altered depending on the activity, type of the disease, and antibiotic
therapy, suggesting its probable role in infl ammatory events of the intestine
Yield estimation and forecasting for winter wheat in Hungary using time series of MODIS data
Biocompatibility study of poly(vinyl alcohol)-based electrospun scaffold for hernia repair
Abdominal hernia is a purely surgical disorder where due to a defect in the abdominal wall, tissues or organs can extrude out of the abdominal cavity. The only conclusive treatment is surgical making a mesh implantation indispensable. Tissue engineering is now a promising method for creating scaffolds that provide an adequate support for tissue ingrowth. Our purpose was to develop a non-adhesive hernia mesh, which could be used in the repair of abdominal wall hernias but concurrently a scaffold for abdominal tissue regeneration. Poly(vinyl alcohol) bulk hydrogels are promising materials in wound dressing hence, interest in electrospun poly(vinyl alcohol) meshes has emerged in the past few years for different biomedical applications. In the present paper, preparation of electrospun poly(vinyl alcohol) fiber membranes and their in vitro and in vivo behaviors were followed to study the adhesion, biocompatibility, and biodegradability of the meshes. Our results showed that the surface of PVA meshes does not favor cell adhesion in vitro. During the animal experiments, PVA meshes demonstrated good integration into the surrounding tissue with minimal inflammatory reaction and minimal adhesions to intra abdominal structures
Scanning tip measurement for identification of point defects
Self-assembled iron-silicide nanostructures were prepared by reactive deposition epitaxy of Fe onto silicon. Capacitance-voltage, current-voltage, and deep level transient spectroscopy (DLTS) were used to measure the electrical properties of Au/silicon Schottky junctions. Spreading resistance and scanning probe capacitance microscopy (SCM) were applied to measure local electrical properties. Using a preamplifier the sensitivity of DLTS was increased satisfactorily to measure transients of the scanning tip semiconductor junction. In the Fe-deposited area, Fe-related defects dominate the surface layer in about 0.5 μm depth. These defects deteriorated the Schottky junction characteristic. Outside the Fe-deposited area, Fe-related defect concentration was identified in a thin layer near the surface. The defect transients in this area were measured both in macroscopic Schottky junctions and by scanning tip DLTS and were detected by bias modulation frequency dependence in SCM
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