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561.
Entesar Yaseen Abdo Qaid Zuraidah Abdullah Rahimah Zakaria Idris Long 《International journal of molecular sciences》2022,23(21)
Neuroinflammation following lipopolysaccharide (LPS) administration induces locomotor deficits and anxiety-like behaviour. In this study, minocycline was compared to memantine, an NMDA receptor antagonist, for its effects on LPS-induced locomotor deficits and anxiety-like behaviour in rats. Adult male Sprague Dawley rats were administered either two different doses of minocycline (25 or 50 mg/kg/day, i.p.) or 10 mg/kg/day of memantine (i.p.) for 14 days four days prior to an LPS (5 mg/kg, i.p.) injection. Locomotor activity and anxiety-like behaviour were assessed using the open-field test (OFT). The phosphorylated tau protein level was measured using ELISA, while the expression and density of brain-derived neurotrophic factor (BDNF) and cAMP response element-binding (CREB) protein in the medial prefrontal cortex (mPFC) were measured using immunohistochemistry and Western blot, respectively. Minocycline treatment reduced locomotor deficits and anxiety-like behaviour associated with reduced phosphorylated tau protein levels, but it upregulated BDNF/CREB protein expressions in the mPFC in a comparable manner to memantine, with a higher dose of minocycline having better benefits. Minocycline treatment attenuated LPS-induced locomotor deficits and anxiety-like behaviour in rats and decreased phosphorylated tau protein levels, but it increased the expressions of the BDNF/CREB proteins in the mPFC. 相似文献
562.
Muhammad Saleem Mohammed Harun Chakrabarti Abdul Aziz Abdul Raman Diya’uddeen Basheer Hasan Wan Mohd Ashri Wan Daud Atif Mustafa 《International Journal of Hydrogen Energy》2012
This work presents the results of a two-stage (carbon fixation and hydrogen production) experimental study for hydrogen production from microalgae using optical fiber as an internal light source. Effect of absence and presence of light on Chlamydomonas reinhardtii culture’s pH shift is also evaluated. The culture pH value is a function of light intensity; the pH in the alkaline range changes from 7.5 to 9.5 in the presence and absence of optical fiber respectively. The maximum rate of hydrogen production in the presence of exogenic glucose and optical fiber is 6 mL/Lcult/hour, which is higher than other reported values. This study has also revealed that the presence of light reduces the lag time for hydrogen production from 12 to 5 h. 相似文献
563.
Removal of organic matter is a critical parameter in soil aquifer treatment (SAT) as it governs and influences the removal of other contaminants by biodegradation namely trace organics, nitrogen species and microbes. A framework for analysis and prediction of the performance of SAT systems with respect to removal of organic matter under different water quality and process conditions was developed based on an extensive literature review and data analysis. Guidelines were developed to make preliminary estimates of the removal of organic matter during SAT using primary, secondary and tertiary effluents from wastewater treatment plants. These guidelines can be used as a quick tool to analyze the performance of existing SAT systems and serve as a decision support tool for feasibility studies and to save time for further detailed experimentation and design of SAT systems. Furthermore, effects of soil type and redox conditions on organic matter removal during SAT were also analyzed. 相似文献
564.
Hafizal Yazid Haniza Yazid Mohd Harun Shukri Mohd A. Aziz Mohamed Mohamed Rizon Shaharudin Sayuti 《NDT & E International》2007,40(8):594-601
Conventional radiography is one of the common non-destructive testing which employs manual image interpretation. The interpretation is very subjective and depends much on the inspector experience and working conditions. It is therefore useful to have pattern recognition system in order to assist human interpreter in evaluating the quality of the radiographed sample, especially radiographic image of welded joint. This paper describes a system to detect circular discontinuities that are present in the joints. The system utilizes together two different algorithms, which are separability filter to identify the best object candidate and Circular Hough Transform to detect the presence of circular shape. The result of the experiment shows a promising output in recognition of circular discontinuities in a radiographic image. This is based on 81.82–100% of radiography film with successful circular detection by using template movement of 10 pixels. 相似文献
565.
Abdelmoumen Norrdine Zakaria Kasmi Jörg Blankenbach 《Journal of Location Based Services》2016,10(1):3-15
A magnetic indoor local positioning system enables positioning in harsh environments due to the advantageous characteristics of magnetic signals such as penetrating of various obstacles and robustness against fading effects. Nevertheless, the indoor tracking remains a challenge, due to the non-stationary property of the ambient magnetic fields, signal transients and eddy current effects. In this paper, we propose a method, which is based on zero velocity detection, in order to overcome the mentioned constraints by the pedestrian tracking. 相似文献
566.
Foaming temperature and grade of dry natural rubber were varied to evaluate their effects on the morphology and mechanical properties of natural rubber (NR) foams. Three different grades of NR were used; namely ENR‐25, SMR‐L, and SMR‐10. NR foams from these grades were produced at three different foaming temperatures, i.e. 140, 150, and 160°C. The study was carried out using formulated compositions containing sodium bicarbonate as the chemical blowing agent and were expanded using conventional compression molding technique via a heat transfer foaming process. The NR foams were characterized with respect to their relative foam density, density of crosslinking, cell size, compression stress, and compression set. Increase in foaming temperature resulted in lower relative density and larger cell size. It was also discovered that the crosslink density slightly decrease with increasing foaming temperature. For mechanical properties, the highest foam density resulted in the highest compression stress. Compression stress at 50% strain increased with increasing foaming temperature and ENR‐25 foam has the highest compression stress among the produced foams. The results showed that the morphology, physical, and mechanical properties of the rubber foams can be controlled closely by the foaming temperature and rubber grades. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
567.
568.
Kernel elongation in rice 总被引:1,自引:0,他引:1
Kernel elongation after cooking is an important character of fine rice and most rice consumers prefer length‐wise elongation. Although improvement of aromatic rice began early in the 1970s, until now the mechanisms and genetics of kernel elongation has remained unrevealed. Kernel elongation is considered as a physical phenomenon and is influenced by several physicochemical and genetic factors, including genotypes, aging temperature, aging time, water uptake, amylose content and gelatinization temperature. Recently the complete genetic map of fine rice has been created and the gene responsible for kernel length identified; moreover, this gene is tightly linked with the cooked kernel elongation trait. Several molecular markers linked with cooked kernel elongation have been developed. These tools will be helpful for the improvement of this important trait. For the proper study of cooked kernel elongation of rice, this review paper will provide the basis and directional materials for further studies.© 2012 Society of Chemical Industry 相似文献
569.
Mazlin Bin Mokhtar Ahmad Zaharin Aris Mohd Harun Abdullah Mohd Kamil Yusoff Md. Pauzi Abdullah Abd. Rahim Idris & Raja Ibrahim Raja Uzir 《Water and Environment Journal》2009,23(3):219-228
The chemical characteristics of the surface water of Eucalyptus River, in Maliau Basin, were studied based on its major ion chemistry and its suitability for drinking, domestic use and irrigation. Water samples from the river were collected and analysed for pH, temperature, dissolved oxygen (DO), electrical conductivity (EC), total dissolved solids (TDS), turbidity, Cl, SO4 , Ca, Mg, Na and K. Besides major elements, Cu, Zn, Ni, Co, Fe, Mn, Cr, Bi, Cd, Ba, Pb, As, Al, V, Se, Ag, Sr and Li were also determined in this study. The results show that the river water of the area reflects natural factors and is regarded as fresh water and suitable for drinking and domestic use. The calculated values of sodium adsorption ratio (SAR), Mg hazard and salinity hazard indicate that the river water is of high quality and suitable for agricultural and irrigation purposes. This study contributes baseline data for a pristine, forested environment for future reference. 相似文献
570.
Jamal Bentahar Zakaria Maamar Wei Wan Djamal Benslimane Philippe Thiran Sattanathan Subramanian 《Service Oriented Computing and Applications》2008,2(4):219-238
The objective of this paper is to discuss how to sustain the growth of Web services through the use of communities. A community
aims at gathering Web services with the same functionality independently of their origins, locations, and functioning. To
make Web services more responsive to the environment in which they run and to be more flexible when managing communities,
Web services are associated with software agents enhanced with argumentation capacities. This type of agents persuade and
negotiate with other peers for the sake of letting their respective Web services reach their goals in an efficient way. Associating
Web services with this type of agents allows them to select good communities and allow the communities to host the good Web
services and to select the best ones for composite scenarios. Furthermore, this provides satisfactory solutions for three
open problems: starvation (Web services refuse all the possibilities of joining communities), competition-free (Web services
accept joining any community without being selective), and unfairness (always the same Web services members of a community
are selected out of many others to participate in composite scenarios). In addition, the paper presents a formal and computational
persuasive and negotiation protocol to manage the attraction and retainment of Web services in the communities and their identification
for composite services. 相似文献