23 research outputs found

    Ku Telemetry Modulator for Suborbital Vehicles

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    A modulator utilizing the Ku-band instead of the usual S-band has been developed to improve transmission rates for suborbital platforms

    Flexible, reconfigurable, power efficient transmitter and method

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    A flexible, reconfigurable, power efficient transmitter device and method is provided. In one embodiment, the method includes receiving outbound data and determining a mode of operation. When operating in a first mode the method may include modulation mapping the outbound data according a modulation scheme to provide first modulation mapped digital data, converting the first modulation mapped digital data to an analog signal that comprises an intermediate frequency (IF) analog signal, upconverting the IF analog signal to produce a first modulated radio frequency (RF) signal based on a local oscillator signal, amplifying the first RF modulated signal to produce a first RF output signal, and outputting the first RF output signal via an isolator. In a second mode of operation method may include modulation mapping the outbound data according a modulation scheme to provide second modulation mapped digital data, converting the second modulation mapped digital data to a first digital baseband signal, conditioning the first digital baseband signal to provide a first analog baseband signal, modulating one or more carriers with the first analog baseband signal to produce a second modulated RF signal based on a local oscillator signal, amplifying the second RF modulated signal to produce a second RF output signal, and outputting the second RF output signal via the isolator. The digital baseband signal may comprise an in-phase (I) digital baseband signal and a quadrature (Q) baseband signal

    In vivo antinociceptive and anti-inflammatory activities of dried- and fermented-processed virgin coconut oil.

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    Objective: The present study was carried out to investigate the antinociceptive and anti-inflammatory activities of virgin coconut oil (VCO) produced by theMalaysian Agriculture Research and Development Institute (MARDI) using various in vivo models. Materials and Methods: Two types of VCOs, produced via standard drying (VCOA) and fermentation (VCOB) processes were used in this study. Both VCOA and VCOB were serially diluted using 1% Tween 80 to concentrations (v/v) of 10, 50 and 100%. Antinociceptive and anti- inflammatory activities of both VCOs were examined using various in vivomodel systems. The antinociceptive activity of the VCOs were compared to those of 1% Tween 80 (used as a negative control), morphine (5 mg/kg) and/or acetylsalicylic acid (100 mg/kg). Results: Both VCOA and VCOB exhibited significant (p < 0.05) dose-dependent antinociceptive activity in the acetic acid-induced writhing test. Both VCOs also exerted significant (p < 0.05) antinociceptive activity in both phases of the formalin and hot-plate tests. Interestingly, the VCOs exhibited anti-inflammatory activity in an acute (carrageenan-induced paw edema test), but not in a chronic (cotton-pellet-induced granuloma test) model of inflammation. Conclusion: The MARDI-produced VCOs possessed antinociceptive and anti-inflammatory activities. Further studies are needed to confirm these observations

    Involvement of CYP450 system in hepatoprotective activity of Malaysian Agricultural Research and Development Institute (MARDI)-produced virgin coconut oils.

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    The present study aims to determine the role of cytochrome P450 (CYP450) enzyme system in hepatoprotective activity of virgin coconut oils produced by Malaysian Agricultural Research and Development Institute (MARDI). Paracetamol (PCM)-induced hepatotoxic rat was used as a model. Liver injury induced by 3 g/kg PCM increased the liver weight and liver enzymes (e.g. alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphate (ALP)) and decreased cell viability indicating liver damage. Histological observation also confirms liver damage indicated by the presence of inflammations and necrosis. Pre-treatment with VCOA or VCOB reversed the significantly (P < 0.05) reversed PCM toxic effect. Groups pre-treated withvirgin coconut oil (VCOs) followed by inhibitor or inducer of CYP450 demonstrated significant (P < 0.0.5) increase in liver weight, liver enzymes levels and decrease in cell viability, which are, however, significantly (P < 0.05) less remarkable as compared to group treated with PCM alone. In conclusion, VCO possessed hepatoprotective effect, which is believed to be mediated via a non-CYP450 system and might be associated partly with the antioxidant potential of the oil. Further studies are warranted to determine the actual mechanisms of hepatoprotection involved

    The effects of conventional and microwave heating techniques on extraction yield of orthosiphon stamineus leaves

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    The heating technique in a solid-liquid extraction system plays a significant role in the design and economic potential for the extraction of active components from herbs. This paper focused on the effects of extraction parameters such as ratio of sample to solvent, temperature and time of processing on the extraction yield of Orthosiphon stamineus leaves in conventional and microwave heating extraction techniques. The extracts were concentrated and dried using a rotary evaporator and freeze dryer in order to relate the yield to the processing parameters quantitatively in both heating techniques. The analysis results revealed that the processing parameters; ratio of sample to solvent, temperature and time of extraction had essential effects on the extraction yield of Orthosiphon stamineus leaves. Microwave heating extraction produced a comparable yield to conventional heating extraction with a relatively small deviation of approximately 2.8 % in average. Furthermore, microwave heating extraction reduced processing time, where this technique required about 25 % of the conventional heating time in heating up the extraction mixture to set-point temperature (60 ºC). This study concludes that microwave heating extraction, which is a green technology, has great potential in reducing the carbon foot print due to a shorter processing time and reduced energy consumption (~77 % less) compared to conventional heating extraction

    Antihypercholesterolemia property and fatty acid composition of MARDI-produced virgin coconut oils

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    Virgin coconut oil (VCO), or in Malays known as ‘minyak kelapa dara’, has gain a lot of attention recently due to various medicinal values. The aim of the present study was to evaluate the effect of feeding two types of VCOs, VCOA (produced via a standard drying method) or VCOB (prepared via fermentation process), that were produced by Malaysia Agriculture Research and Development Institute (MARDI) in lowering the plasma lipid parameter in rabbits. Nine groups of New Zealand White male rabbits (n = 6/group) were used in this study. Group 1 and 2 animals were treated with 0.9% normal saline, but fed either with a normal or cholesterol-added diet (negative control), respectively. Group 3 - 5 and 6 - 8 were given orally with the different volume (0.5, 1.0 and 2.5 ml/kg/day) of VCOA or VCOB followed by the cholesterol-added diet. Group 9 were treated with 5 mg/kg Atorvastatin and fed a cholesterol-added diet. All groups were treated for 8 weeks and blood samples were taken from the marginal ear vein prior to treatment (day 0), weeks 4 and 8 for the analysis of plasma. The rabbits fed with different volume of VCOs showed significant (P < 0.05) reduction in plasma cholesterol and LDL cholesterol levels compared to the control group in weeks 4 and 8. The triglycerides level increased significantly (P < 0.05) on week 4 before reduced on week 8, to a level that is still significant when compared to week 0. The HDL level also increased significantly (P < 0.05) on weeks 4 and 8 after treatment. Fatty acid analysis revealed the presence of all important fatty acids. Both VCOs showed insignificant effect on all parameters measured when compared together. In conclusion, the MARDI-produced VCOs appeared to possess great potentials as antihypercholesterolemic agent that required further in-depth study

    Rapid spectrophotometric determination, characterization and anti-inflammatory efficacy evaluation of nanoencapsulated diclofenac sodium

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    This study was aimed to develop a simple and reproducible spectrophotometric method for the characterization of diclofenac sodium (DS) and to evaluate the efficacy of orally administered liposome encapsulated as well as free form DS in animal model. A simple, rapid and economical spectrophotometric analytical procedure with estimation in UV-visible region was performed on DS using dimethyl sulfoxide as solvent. Parameters such as time, temperature and types of solvent were studied for 20 μg/mL DS solution at 295 nm. All parameters and results of analysis were statistically validated. Liposome-encapsulated and free form DS samples were subjected to characterization study that includes entrapment efficacy determination and particle size analysis. Drug samples were further tested for their in vivo anti-inflammatory efficacy using histamine-induced paw edema test. Under optimized parameters, the Beer’s law is obeyed in range of 0.625-40 μg/mL at λmax 295 nm. A linear working range of 5-35 μg/mL with regression coefficient of 0.9978 was obtained by using seven triplicate analyses of drug samples at seven different concentrations. The limit of detection and limit of quantitation was 1.19 and 3.62 μg/mL, respectively. Result of characterization study showed that the optimum formulation, which has high entrapment efficacy of 87 %, homogenous in size (polydispersity index 0.27), stable and reproducible, were obtained by using the Pro-Lipo Duo with 10 h hydration time and 16 mg/g DS. The liposome encapsulated DS resulted in significant (P < 0.05) inhibition up to 86 % in histamine-induced paw edema test. Present study successfully demonstrated an optimized procedure as per ICH guidelines in detection and evaluation of DS. In addition, nano-encapsulation of DS using liposome was found to demonstrate a potential enhancement in therapeutic efficacy

    Association of respiratory symptoms and lung function with occupation in the multinational Burden of Obstructive Lung Disease (BOLD) study

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    Background Chronic obstructive pulmonary disease has been associated with exposures in the workplace. We aimed to assess the association of respiratory symptoms and lung function with occupation in the Burden of Obstructive Lung Disease study. Methods We analysed cross-sectional data from 28 823 adults (≥40 years) in 34 countries. We considered 11 occupations and grouped them by likelihood of exposure to organic dusts, inorganic dusts and fumes. The association of chronic cough, chronic phlegm, wheeze, dyspnoea, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)/FVC with occupation was assessed, per study site, using multivariable regression. These estimates were then meta-analysed. Sensitivity analyses explored differences between sexes and gross national income. Results Overall, working in settings with potentially high exposure to dusts or fumes was associated with respiratory symptoms but not lung function differences. The most common occupation was farming. Compared to people not working in any of the 11 considered occupations, those who were farmers for ≥20 years were more likely to have chronic cough (OR 1.52, 95% CI 1.19–1.94), wheeze (OR 1.37, 95% CI 1.16–1.63) and dyspnoea (OR 1.83, 95% CI 1.53–2.20), but not lower FVC (β=0.02 L, 95% CI −0.02–0.06 L) or lower FEV1/FVC (β=0.04%, 95% CI −0.49–0.58%). Some findings differed by sex and gross national income. Conclusion At a population level, the occupational exposures considered in this study do not appear to be major determinants of differences in lung function, although they are associated with more respiratory symptoms. Because not all work settings were included in this study, respiratory surveillance should still be encouraged among high-risk dusty and fume job workers, especially in low- and middle-income countries.publishedVersio

    Mapping 123 million neonatal, infant and child deaths between 2000 and 2017

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    Since 2000, many countries have achieved considerable success in improving child survival, but localized progress remains unclear. To inform efforts towards United Nations Sustainable Development Goal 3.2—to end preventable child deaths by 2030—we need consistently estimated data at the subnational level regarding child mortality rates and trends. Here we quantified, for the period 2000–2017, the subnational variation in mortality rates and number of deaths of neonates, infants and children under 5 years of age within 99 low- and middle-income countries using a geostatistical survival model. We estimated that 32% of children under 5 in these countries lived in districts that had attained rates of 25 or fewer child deaths per 1,000 live births by 2017, and that 58% of child deaths between 2000 and 2017 in these countries could have been averted in the absence of geographical inequality. This study enables the identification of high-mortality clusters, patterns of progress and geographical inequalities to inform appropriate investments and implementations that will help to improve the health of all populations
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