522 research outputs found
Polysaccharides derived from tragacanth as biocompatible polymers and Gels
No full textTragacanth gum (TG) is a natural gum whose biomedical applications are limited because of the low water solubility and the possibility to form only weak water-insoluble gels. An innovative method to produce water-soluble tragacanth (WST) is assessed in this work. WST structural characterization indicates a high-molecular weight polyuronic acid, which can undergo gelling by ionotropic complexation. Biological characterization shows no cytotoxicity on Hela, HepG2, and L929 cell lines. Furthermore, TG-based and WST-based gel beads prepared by ionic crosslinking with ferric and zinc ions are studied. Ferric WST gels exerted better cell adhesion with L929 cells than ferric alginate gels. These characteristics make WST a promising candidate for tissue engineering and drug delivery application
Evaluation of morphologic method for the detection of nervous tissue in minced meat
No full textProducing meat products with ingredients which are not consistent with the label is considered fraud. Due to the high economic value of meat, the use of unauthorized tissue in meat products is possible. Aside from the adulteration aspect, it is important to note that some animal tissues like the brain and the spinal cord can bear infective agents which are transmissible to humans. Based on these observations, the aim of the present study was to apply morphological method for detection of nervous tissues in minced meat. Laboratory adulterated minced beef meat; each containing 0, 5, 10, 15 and 20% of beef brain was prepared. Then each sample was divided into three parts and four paraffin embedded blocks were prepared from each part. The sections were stained using sudan black and cresyl violet and also the immunohistochemical staining with fluorescent method were applied using anti-neurofilament 200 antibody for the determination of nervous tissue. Although the neuronal cell bodies and neuronal fibers were clearly detectable in Cresyl violet staining and sudan black staining, respectively, however, staining intensity did not show any difference according to different percentages of added brain. In contrary, immunohistochemical study revealed that neurofilament 200- immunolabeling was present in all percentages of added brain samples and the intensity of the labeling varying from weak to strong consisted by the increasing the amount of brain in samples. In conclusion, the immunohistochemical technique with fluorescent method is an effective method for evaluations of additive brain tissue in minced meat with high sensitivity
Mapping QTL controlling agronomic traits in a doubled haploid population of winter oilseed rape (Brassica napus L.)
No full textAACR2 and catalogue production technology: The relevance of cataloguing principles to the online environment
No full textMore than thirty five years have passed since the Paris Conference and cataloguers have witnessed profound changes in many aspects of catalogue production technology and also in bibliographic control and access during this period of time. In comparison to the past, cataloguers are less involved in the design and production of catalogues and bibliographic databases particularly in terms of the interfaces, the types of indexes and the ways in which records and retrieval results are displayed. These changes and developments (see Appendix one) have presented cataloguers with some basic questions about the fundamental principles of record creation and catalogue construction.
Although present online catalogues are benefiting from more advanced hardware and software, there are still considerable, serious problems in searching, retrieval, and display of bibliographic information in present systems, which influence their functions and usefulness. This, as has been highlighted in the literature, may be because some of the present cataloguing principles and rules are inadequate, less relevant or irrelevant to the new electronic environment. A review of the literature of the last two decades indicates that, parallel to the increasing developments in online catalogues, the cataloguing community has been addressing the need for a re-thinking of cataloguing principles and rules in light of the new environment. It is often claimed that AACR2’s rules are based on concepts and principles from the pre-machine period and that they do not serve us well in giving guidance in the construction of electronic catalogues.
Given the influence of all the changes and developments in the world of catalogues and cataloguing, a fundamental re-examination of our cataloguing principles seems very necessary. In this paper some of the basic principles of AACR2 which have been highlighted in the literature as those most likely to be influenced by the new technology will be re-examined in the light of both the present and the potential characteristics and capabilities of the online environment. The aim is to examine the extent to which AACR2 matches or fails to match the capabilities of present systems and those of the near future, for searching, retrieval and display of bibliographic information. In other words, to address how catalogue form and production affects, or is in turn influenced by, the principles upon which AACR2 is based.
The approach used in this paper is to match individual capabilities of online catalogues with the basic principles of AACR2R. A major focus will be the basic concepts of the code’s principles, the logic of their application and the relationship of these principles to the logic of the online catalogue, as well as an examination of the types of principles and rules that are likely to change when moving from a manual catalogue to an online catalogue. In this regard, the needs and expectations of the different catalogue users are also taken into consideration
Speciation of Tc(IV) in chloride solutions by capillary electrophoresis
No full textBrowse Search My Profile Activate Help Home > List of Issues > Table of Contents > Abstract Speciation of Tc(IV) in chloride solutions by capillary electrophoresis Author(s): Xiaolan Liu | Frédéric Poineau | Massoud Fattahi | Bernd Grambow | L. Vichot doi: 10.1524/ract.93.5.305.64276 View PDF article (245 K) View table of contents Email this link Add to my alerts What is RSS? Trouble viewing articles as PDF? Radiochimica Acta Print ISSN: 0033-8230 Volume: 93 | Issue: 5/2005 Cover date: 20050501 Page(s): 305-309 Abstract text A method for speciation of Tc(IV) species (TcCl62− and TcCl5(H2O)−) in chloride solutions, using capillary electrophoresis (CE) technique was developed. The proposed method has overcome the difficulties of unstable oxidation states analysis by shortening their travel time in the capillary. TcCl62− and TcCl5(H2O)− were thus separated without being hydrolyzed and polymerized, and their UV/Vis spectra were recorded. With a 1 M HCl/NaCl buffer solution (pH=1), the electrophoretic mobilities were determined as 5.47×10−4 cm2/Vs for TcCl62− and 2.13×10−4 cm2/Vs for TcCl5(H2O)− at 25 °C. The total analysis time for one run is 12 minutes
The Effect of 8-Methoxypsoralen on Pituitary-Gonad Axis and Ovarian Function in Mice
No full textObjective: 8-Methoxypsoralen (8-MOP) is a photoactive compound widely used in the treatment of proliferate disorders. The present study investigates the effects of 8-MOP on ovary function and pituitary-gonad axis in mice.Materials and Methods: In this experimental analytical study, 45 female Balb/C mice were divided into three groups (n=15), control, sham (olive oil injection) and experimental. The experimental group were received an intraperitoneal (i.p.) injection of the LD50 dose of 60 mg/kg 8-MOP. At 30 days after injection, the animals were sacrificed while in the proestrus stage and examined for morphological and histological changes their ovaries. Blood samples were collected and estrogen, luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels were assessed by radioimmunoassay. Data were analyzed using one-way ANOVA and the t test.Results: The mean levels of estrogen and progesterone in the experimental group significantly decreased (p<0.001). However, there was a significant increase in LH and FSH levels in this group compared to the control groups (p<0.001). The mean number and diameter of the corpus luteum (CL) and the number of growing follicles in the experimental group significantly reduced compared to the control and sham groups (p<0.001). The mean granulosa thickness in the experimental group also significantly decreased compared to the control and sham groups (p<0.001).Conclusion: Our data indicated that 8-MOP can affect the levels of LH, FSH, estrogen and progesterone. Our findings further suggest that consecutive doses of 8-MOP may impair the female reproductive tract (or development)
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Mass Customization: Theories and Application
No full textAs a general trend, firms are moving towards mass customization by allowing customers to configure products by selecting among options (features), e.g. automotive industry, consumer electronics, computers, furniture, and aircraft. This dissertation is motivated by the problems faced by a global auto manufacturer that offers 100-500 options for a car. These options can be combined in different ways resulting in 10^25-10^40 different configurations (end-products). Since it is impossible to forecast the demand for configurations, firms forecast options' demand.In this dissertation, we study three major problems. First, the current forecasting approach ignores the relationships between options and, as a result, the forecasts are frequently incorrect (inconsistent), which results in excess inventories, shortages, and customer dissatisfaction. We present an effective approach that verifies consistency of the forecast and finds the best consistent forecast in the case of inconsistency. The second problem is to determine how many units of each part is required over the planning horizon, known as parts' capacity planning problem. The firm signs contracts with parts' suppliers based on the predicted parts' capacities. We present a methodology for predicting parts' capacities. Last, we generalize and extend the methodology developed in the first problem and introduce a new variation of the Non-Negative Least-Squares (NNLS) problem that is defined as finding the Euclidean distance to a convex cone generated by a set of discrete points. Our new variation considers the cases where the discrete points are implicitly known and there are an exponentially large number of them. We present an effective approach for solving this new variation of NNLS, design a lower bound, and establish the convergence rate of the lower and upper bounds
The Seroprevalence of Hepatitis B in Akbar Abad Village, Kavar, Southern Iran
No full textBackground: About 2 billion people were reported to be infected with hepatitis B virus (HBV) and among them; 350 million are chronically infected cases. This study was performed to determine the prevalence of hepatitis B in Kavar, southern Iran.
Methods: From August 2008 to March 2009, 3739 individuals aged between 1 and 88 years were screened for infection with HBV in Akbar Abad Village, Kavar, Southern Iran. A questionnaire was used to record demographic data, history of vaccination and the correlated risk factors. Ten milliliter of the blood sample was taken from each subject. Sera were checked for hepatitis B surface antigen (HBs Ag) and hepatitis B core antibody (HBC Ab).
Results: Among subjects, 7.1% were positive for HBC Ab and 2.2% for HBS Ag. Out of positive cases for HBC Ab, 7.3% were female, and 7.6% were male. Out of positive cases for HBS Ag, 2.2% were female, and 2.5% were male. The minimal rates of HBC Ab and HBS Ag were noticed in the age group 1-15 year old. The highest positivity was observed among unemployed individuals. Among subjects with low educational level, 7.5% were positive for HBC Ab and 2.4% for HBS Ag. The highest prevalence was visible in the widow group and the lowest in married persons. Opium addiction had a significant relationship with HBC Ab. The prevalence of HBV seropositivity was higher among drivers, those with a history of dental treatments and family history of liver diseases blood transfusion tattooing recipients.
Conclusions: Our results showed that screening of pregnant women for HBs Ag and vaccination of high-risk individuals including family members of patients with hepatitis B should be implemented in future planning
Application of Remote Sensing Techniques for the Study of Neotectonic Deformation, Subsidence and Coastal Processes
No full textRemote sensing is a valuable tool for studying various natural and anthropogenic processes around the world. This work utilizes data collected from spaceborne and airborne platforms to study the effects of subsidence, neotectonic deformation, and coastal change.
The first study covers subsidence and neotectonic deformation in Karachi and surrounding areas on the southern coast of Pakistan. This area is situated along the diffuse western margin of the Indian plate and in close proximity to the active Makran Subduction Zone. I used Interferometric Synthetic Aperture Radar (InSAR) to identify hotspots of subsidence in the city and quantify rates of deformation. This study was the first to report the presence of an active fault within the city.
The second study covers influential factors driving subsidence in Katy, Texas. The greater Houston area has an established history of subsidence driven by groundwater withdrawal, but few studies have focused on other contributing factors. I used InSAR to determine the areas and rates of subsidence and used various publicly available datasets to calculate variables for use in a linear regression model. The results of this study revealed that population growth and total developed area are two of the highest contributors to subsidence in the area.
The third study covers coastal change at two selected sites along the Gulf Coast of Texas: Follett’s and Galveston Islands. Coastal change in the form of shoreline retreat and sediment erosion reduces the protective influence of barrier islands and their beach-dune systems. I conducted an uncrewed aerial vehicle (UAV) survey at these two sites and collected sediment samples for grain size analysis. Using the UAV data, I quantified the change in terms of elevation, sediment volume, and vegetation cover and performed a risk assessment for each site using a Coastal Vulnerability Index. The results determined overall accretion at the Galveston site and erosion at the Follett’s site, and the vulnerability of the sites was classified as moderate risk and very high risk, respectively
A one direction search method to find the exact nondominated frontier of biobjective mixed-binary linear programming problems
No full textThe nondominated frontier (NDF) of a biobjective optimization problem is defined as the set of feasible points in the objective function space that cannot be improved in one objective function value without worsening the other. For a biobjective mixed-binary linear programming problem (BOMBLP), the NDF consists of some combination of isolated points and open, closed, or half-open/half-closed line segments. Some algorithms have been proposed in the literature to find an approximate or exact representation of the NDF. We present a one direction search (ODS) method to find the exact NDF of BOMBLPs. We provide a theoretical analysis of the ODS method and show that it generates the exact NDF. We also conduct a comprehensive experimental study on a set of benchmark problems and show the solution quality and computational efficacy of our algorithm. (C) 2017 Elsevier B.V. All rights reserved
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