164 research outputs found

    Effect of Particle Size on Mechanical Properties of Pellets Made from Biomass Blends

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    AbstractWoody biomass is densified in the form of pellets in order to improve its physical and mechanical properties during handling and storage. However, limited research work has been conducted on the mechanical properties of pellets made from agricultural and wood biomass blends. Two commonly available forestry biomass, spruce (S) and pine (P), and three agricultural biomasses, reed canary grass (RCG), timothy hay (H) and switchgrass (SW), were used to form pellets. The mechanical properties were evaluated for three different particle sizes (150-300, 300-425 and 425-600μm). An Instron attached with an in-house built single unit pelletizer and temperature controlled die was employed to produce a pellet. The aim of this study is to investigate the effect of particle size and blending (agricultural and woody biomass) on the mechanical properties (density and intrinsic yield stress). For all biomasses, pellets made from lower particle size (150-300μm) exhibited higher density (950-1178kg/m3 for spruce and pine; 668-800kg/m3 for RCG, H and SW; 900-970kg/m3 for blended biomass). The intrinsic yield stress exhibited differences in values for individual forestry (40MPa) and agricultural biomass (27-48MPa), however after blending the values converged closest to that value for forestry biomass. In conclusion, blending low cost and abundant available agricultural biomass with woody biomass could not only result in better mechanical properties but would also help to meet the pellet market demand in future

    Assessment of Moisture Effect in Simulating Forestry Biomass Supply Chain Strategy: Case Study of New Brunswick, Canada

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    In order to investigate the effect of variation of the moisture content of forest biomass residues on a supply chain strategy, a simulation was performed using integrated biomass supply analysis and logistics modeling. A simple supply chain strategy was chosen and applied for Miramichi and Plaster Rock, two different regions in New Brunswick, Canada. These regions are selected based on three criteria: annual potential harvest of forest biomass residues, annual production potential of electric and thermal energy and distribution of transportation zones. The moisture content of forest biomass residues was dependant on the weather conditions of the selected regions. The results show that the moisture content of the biomass in Plaster Rock was more stable but higher than the biomass in the Miramichi region. In simulating the supply chain strategy, particular attention is given to harvest, baling, storage and transportation of the biomass. The simulation results show that, during harvest and baling of the biomass, the moisture content affects the dry matter loss and, as a consequence, the customer and ownership costs of the operations. It also affects the energy input and the quantity of carbon dioxide released in the atmosphere. However, dry matter loss and accordingly the cost of the operations are the main parameters affecting the storage and transportation of forest biomass residues

    Erectile dysfunction: prevalence, risk factors and involvement of antihypertensive drugs intervention

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    Purpose: To explore the literature regarding prevalance, risk factors and the involvement of antihypertensive drugs in erectile dysfunction (ED).Methods: Original research articles, reviews, editorials and case reports published in English language on the prevalence of sexual/erectile dysfunction in hypertensive men taking antihypertensive drugs and risk factors were identified through a search of four bibliographic databases, namely, PubMed, EMBASE, CINAHL and EBSCO Health.Results: Recent analyses suggest that hypertensive men of almost all age groups suffer from ED but it is more prevalent in elderly male patients. The involvement of β-blockers was found to be controversial. Nevertheless, some evidence had been found regarding the use of propranolol in high doses.Conclusion: The present review indicates the need for research to unravel the role of β-blockers in the manifestation of ED in hypertensive males, whom there are no contributory factors such as sedentary lifestyle, aging, stress and anxiety, etc.Keywords: Hypertension, Antihypertensive drugs, β-Blockers, Propranolol, Erectile dysfunction, Life style, Risk factor

    Experimental evaluation of vibrotactile training mappings for dual-joystick directional guidance

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    Two joystick-based teleoperation is a common method for controlling a remote machine or a robot. Their use could be counter-intuitive and could require a heavy mental workload. The goal of this paper is to investigate whether vibrotactile prompts could be used to trigger dual-joystick responses quickly and intuitively, so to possibly employ them for training. In particular, we investigate the effects of: (1) stimuli delivered either on the palm or on the back of the hand, (2) with attractive and repulsive mappings, (3) with single and sequential stimuli. We find that 38 participants responded quicker and more accurately when stimuli were delivered on the back of the hand, preferred to move towards the vibration. Sequential stimuli led to intermediate responses in terms of speed and accuracy

    Envelope 2 protein phosphorylation sites S75 & 277 of hepatitis C virus genotype 1a and interferon resistance: A sequence alignment approach

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    <p>Abstract</p> <p>Background</p> <p>Hepatitis C is a major health problem affecting more than 200 million individuals in world including Pakistan. Current treatment regimen consisting of interferon alpha and ribavirin does not always succeed to eliminate virus completely from the patient's body.</p> <p>Results</p> <p>Interferon induced antiviral protein kinase R (PKR) has a role in the hepatitis C virus (HCV) treatment as dsRNA activated PKR has the capacity to phosphorylate the serine and threonine of E2 protein and dimerization viral RNA. E2 gene of hepatitis C virus (HCV) genotype 1 has an active role in IFN resistance. E2 protein inhibits and terminates the kinase activity of PKR by blocking it in protein synthesis and cell growth. This brings forward a possible relation of E2 and PKR through a mechanism via which HCV evades the antiviral effect of IFN.</p> <p>Conclusion</p> <p>A hybrid in-silico and wet laboratory approach of motif prediction, evolutionary and structural anlysis has pointed out serine 75 and 277 of the HCV E2 gene as a promising candidate for the serine phosphorylation. It is proposed that serine phosphorylation of HCV E2 gene has a significant role in interferon resistance.</p

    Age-sex differences in the global burden of lower respiratory infections and risk factors, 1990-2019 : results from the Global Burden of Disease Study 2019

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    BACKGROUND: The global burden of lower respiratory infections (LRIs) and corresponding risk factors in children older than 5 years and adults has not been studied as comprehensively as it has been in children younger than 5 years. We assessed the burden and trends of LRIs and risk factors across all age groups by sex, for 204 countries and territories. METHODS: In this analysis of data for the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, we used clinician-diagnosed pneumonia or bronchiolitis as our case definition for LRIs. We included International Classification of Diseases 9th edition codes 079.6, 466-469, 470.0, 480-482.8, 483.0-483.9, 484.1-484.2, 484.6-484.7, and 487-489 and International Classification of Diseases 10th edition codes A48.1, A70, B97.4-B97.6, J09-J15.8, J16-J16.9, J20-J21.9, J91.0, P23.0-P23.4, and U04-U04.9. We used the Cause of Death Ensemble modelling strategy to analyse 23 109 site-years of vital registration data, 825 site-years of sample vital registration data, 1766 site-years of verbal autopsy data, and 681 site-years of mortality surveillance data. We used DisMod-MR 2.1, a Bayesian meta-regression tool, to analyse age-sex-specific incidence and prevalence data identified via systematic reviews of the literature, population-based survey data, and claims and inpatient data. Additionally, we estimated age-sex-specific LRI mortality that is attributable to the independent effects of 14 risk factors. FINDINGS: Globally, in 2019, we estimated that there were 257 million (95% uncertainty interval [UI] 240-275) LRI incident episodes in males and 232 million (217-248) in females. In the same year, LRIs accounted for 1·30 million (95% UI 1·18-1·42) male deaths and 1·20 million (1·07-1·33) female deaths. Age-standardised incidence and mortality rates were 1·17 times (95% UI 1·16-1·18) and 1·31 times (95% UI 1·23-1·41) greater in males than in females in 2019. Between 1990 and 2019, LRI incidence and mortality rates declined at different rates across age groups and an increase in LRI episodes and deaths was estimated among all adult age groups, with males aged 70 years and older having the highest increase in LRI episodes (126·0% [95% UI 121·4-131·1]) and deaths (100·0% [83·4-115·9]). During the same period, LRI episodes and deaths in children younger than 15 years were estimated to have decreased, and the greatest decline was observed for LRI deaths in males younger than 5 years (-70·7% [-77·2 to -61·8]). The leading risk factors for LRI mortality varied across age groups and sex. More than half of global LRI deaths in children younger than 5 years were attributable to child wasting (population attributable fraction [PAF] 53·0% [95% UI 37·7-61·8] in males and 56·4% [40·7-65·1] in females), and more than a quarter of LRI deaths among those aged 5-14 years were attributable to household air pollution (PAF 26·0% [95% UI 16·6-35·5] for males and PAF 25·8% [16·3-35·4] for females). PAFs of male LRI deaths attributed to smoking were 20·4% (95% UI 15·4-25·2) in those aged 15-49 years, 30·5% (24·1-36·9) in those aged 50-69 years, and 21·9% (16·8-27·3) in those aged 70 years and older. PAFs of female LRI deaths attributed to household air pollution were 21·1% (95% UI 14·5-27·9) in those aged 15-49 years and 18·2% (12·5-24·5) in those aged 50-69 years. For females aged 70 years and older, the leading risk factor, ambient particulate matter, was responsible for 11·7% (95% UI 8·2-15·8) of LRI deaths. INTERPRETATION: The patterns and progress in reducing the burden of LRIs and key risk factors for mortality varied across age groups and sexes. The progress seen in children younger than 5 years was clearly a result of targeted interventions, such as vaccination and reduction of exposure to risk factors. Similar interventions for other age groups could contribute to the achievement of multiple Sustainable Development Goals targets, including promoting wellbeing at all ages and reducing health inequalities. Interventions, including addressing risk factors such as child wasting, smoking, ambient particulate matter pollution, and household air pollution, would prevent deaths and reduce health disparities. FUNDING: Bill & Melinda Gates Foundation

    Hepatitis C virus to hepatocellular carcinoma

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    Hepatitis C virus causes acute and chronic hepatitis and can lead to permanent liver damage and hepatocellular carcinoma (HCC) in a significant number of patients via oxidative stress, insulin resistance (IR), fibrosis, liver cirrhosis and HCV induced steatosis. HCV induced steatosis and oxidative stress causes steato-hepatitis and these pathways lead to liver injury or HCC in chronic HCV infection. Steatosis and oxidative stress crosstalk play an important role in liver damage in HCV infection. This Review illustrates viral and host factors which induce Oxidative stress, steatosis and leads toward HCC. It also expresses Molecular cascade which leads oxidative stress and steatosis to HCC
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