135 research outputs found

    Greenhouse gas (GHG) emissions from land transports in Malaysia: modelling and policy analysis

    Get PDF
    Transportation sector is important to the economy and its rapid development has contributed significantly to the socioeconomic development of the country. The transportation sector in Malaysia accounts for approximately 35% of the total energy consumed nationally and produces nearly 50 million tonne of CO2 per year in 2015, second only to electricity power generation. Though shares only 0.3% of global GHG (Greenhouse gas) emissions, Malaysia is second largest per capita GHG emitter among the group of ASEAN countries and the major concern lies in the ever increasing trends. The aim of this work was to perform dynamic quantitative emission analysis of Malaysian vehicle fleet until year 2040, primarily on land transports including both passenger and freight transports except train. Utilizing a System Dynamic approach using Powersim Studio®, several emission scenarios were modelled in compared to current scenario (baseline model). The baseline model was used to determine carbon dioxide (CO2), carbon monoxide (CO) and nitrogen oxides (NOx) reduction for different policy scenarios in compared to baseline scenario. The complex relationships between the various components in the transport system are reflected in the dynamic model considering the vehicle technology, legislation and drivers’ attitude. This work found that CO2 emission in 2040 can be reduced by up to 50%, compared to baseline scenario, without affecting the economy and vehicle demand. Carbon dioxide and nitrogen oxides pollution can also be reduced by 75% and 93% respectively with implementation of several policies compared to baseline scenario

    Renewable energy support policy in Malaysia: a comparative analysis with two successful countries

    Get PDF
    The world is facing depletion of fossil fuel sources thus urged for alternative and renewable energy sources. The conventional energy production raised a concern regarding greenhouse gases (GHG) emission that has led experts to find ways in reducing it. Energy production from renewable energy sources needs efficient support mechanisms to be successful. Many EU (European Union) countries namely Germany, Sweden, Finland and Denmark have been successful in deploying renewable energy sources by enacting judicial policy support mechanisms. Malaysia too has utilized several policies for promoting renewable energy but its success is yet very low. This paper is aimed to analyze renewable energy policies of Malaysia as to compare with selected EU countries successful policies. RETScreen software is used to analyze policies cases for Solar PV and Biomass sources. A comparative analysis is done for Malaysia with Germany and Sweden to obtain the estimation of net present value, internal rate of return and payback period. The finding provides indication why Malaysia renewable energy policy is not efficient as the two EU countries. The paper also discovers that the proposed policy for Malaysia has shown to a better option for future policies embedment

    Response of potato to ash as an alternative source of potassic fertilizer

    Get PDF
    An experiment was carried out during rabi season of 2011-2012 in the experimental field of Soil Science, Bangladesh Agricultural University (BAU), Mymensingh. The objectives of present research work was to evaluate ash as an alternative source of potassic fertilizer for potato cultivation. The treatment combinations were i) Control (No K), ii) 100% K of recommended dose from muriate of potash (MoP), iii) 75% K from MoP+ 25% K from ash, iv) 50% K from MoP + 50% K from ash, v) 25% K from MoP + 75% K from ash, and vi) 100% K from ash. The result of the experiment indicated that various combinations of ash and MoP influenced the yield, yield contributing characters (length of the tubers, breadth of the tubers, number of tubers per hill, weight of tubers per hill, weight of ten tubers and gross yield of tubers per plot), K content of potato as well as weed infestation. Among the treatments the highest yield was obtained from 50% K from MoP + 50% from ash (T3) treated plot. The K content in the potato tuber and weed infestation was also highest for that plot. Considering the yield contributing parameters, yield and number of weeds the T3 (50% K from MoP + 50% K from ash) treatment was found more suitable than others

    The effect of different feed formulation based on local feed resource on performance and stress parameter in breeder goat

    Get PDF
    Balanced nutrition is essential for health and performance of livestock. It is best when feed is formulated according to production stages of goat. However, as the goat grows, it may undergo transition of different feed formulation to meet its daily requirement. The transition may affect the performance of animals as well as it is a stressful condition. In this study, body weight gain and feed intake were used as indicators on performance, whereas hematological stress leucograms were used as indicator of stress parameter during implementation of different feed formulation among does. Eighteen adult does with similar body condition score and body weight approximately 20 kg were selected and divided into three groups equally (n = 6) and fed with different feed formulations, which were formulated using local feed source in the farm for a period of four weeks. Body weight was measured before implementation, on week 2 and week 4, blood sampling was conducted before implementation and during week 4 for comparison and feed intake was measured every day. All data were statistically analyzed using SPSS. Does fed with Diet 3 showed highest body weight gain and feed intake, followed by Diet 2 and Diet 1. There was significant difference (P0.05) as compared to normal value. Neutrophils:lymphocytes ratio for all groups were within normal range and no significant difference (P>0.05). The implementation of feed formulation according to production stages is recommended as it increases performance and prevents from nutritional stress

    Competence in Endoscopic Ultrasound and Endoscopic Retrograde Cholangiopancreatography, From Training Through Independent Practice.

    Get PDF
    BACKGROUND & AIMS: It is unclear whether participation in competency-based fellowship programs for endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) results in high-quality care in independent practice. We measured quality indicator (QI) adherence during the first year of independent practice among physicians who completed endoscopic training with a systematic assessment of competence. METHODS: We performed a prospective multicenter cohort study of invited participants from 62 training programs. In phase 1, 24 advanced endoscopy trainees (AETs), from 20 programs, were assessed using a validated competence assessment tool. We used a comprehensive data collection and reporting system to create learning curves using cumulative sum analysis that were shared with AETs and trainers quarterly. In phase 2, participating AETs entered data into a database pertaining to every EUS and ERCP examination during their first year of independent practice, anchored by key QIs. RESULTS: By the end of training, most AETs had achieved overall technical competence (EUS 91.7%, ERCP 73.9%) and cognitive competence (EUS 91.7%, ERCP 94.1%). In phase 2 of the study, 22 AETs (91.6%) participated and completed a median of 136 EUS examinations per AET and 116 ERCP examinations per AET. Most AETs met the performance thresholds for QIs in EUS (including 94.4% diagnostic rate of adequate samples and 83.8% diagnostic yield of malignancy in pancreatic masses) and ERCP (94.9% overall cannulation rate). CONCLUSIONS: In this prospective multicenter study, we found that although competence cannot be confirmed for all AETs at the end of training, most meet QI thresholds for EUS and ERCP at the end of their first year of independent practice. This finding affirms the effectiveness of training programs. Clinicaltrials.gov ID NCT02509416

    Competence in Endoscopic Ultrasound and Endoscopic Retrograde Cholangiopancreatography, From Training Through Independent Practice.

    Get PDF
    BACKGROUND & AIMS: It is unclear whether participation in competency-based fellowship programs for endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) results in high-quality care in independent practice. We measured quality indicator (QI) adherence during the first year of independent practice among physicians who completed endoscopic training with a systematic assessment of competence. METHODS: We performed a prospective multicenter cohort study of invited participants from 62 training programs. In phase 1, 24 advanced endoscopy trainees (AETs), from 20 programs, were assessed using a validated competence assessment tool. We used a comprehensive data collection and reporting system to create learning curves using cumulative sum analysis that were shared with AETs and trainers quarterly. In phase 2, participating AETs entered data into a database pertaining to every EUS and ERCP examination during their first year of independent practice, anchored by key QIs. RESULTS: By the end of training, most AETs had achieved overall technical competence (EUS 91.7%, ERCP 73.9%) and cognitive competence (EUS 91.7%, ERCP 94.1%). In phase 2 of the study, 22 AETs (91.6%) participated and completed a median of 136 EUS examinations per AET and 116 ERCP examinations per AET. Most AETs met the performance thresholds for QIs in EUS (including 94.4% diagnostic rate of adequate samples and 83.8% diagnostic yield of malignancy in pancreatic masses) and ERCP (94.9% overall cannulation rate). CONCLUSIONS: In this prospective multicenter study, we found that although competence cannot be confirmed for all AETs at the end of training, most meet QI thresholds for EUS and ERCP at the end of their first year of independent practice. This finding affirms the effectiveness of training programs. Clinicaltrials.gov ID NCT02509416

    Advances, challenges and future directions for stem cell therapy in amyotrophic lateral sclerosis

    Get PDF
    Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative condition where loss of motor neurons within the brain and spinal cord leads to muscle atrophy, weakness, paralysis and ultimately death within 3–5 years from onset of symptoms. The specific molecular mechanisms underlying the disease pathology are not fully understood and neuroprotective treatment options are minimally effective. In recent years, stem cell transplantation as a new therapy for ALS patients has been extensively investigated, becoming an intense and debated field of study. In several preclinical studies using the SOD1G93A mouse model of ALS, stem cells were demonstrated to be neuroprotective, effectively delayed disease onset and extended survival. Despite substantial improvements in stem cell technology and promising results in preclinical studies, several questions still remain unanswered, such as the identification of the most suitable and beneficial cell source, cell dose, route of delivery and therapeutic mechanisms. This review will cover publications in this field and comprehensively discuss advances, challenges and future direction regarding the therapeutic potential of stem cells in ALS, with a focus on mesenchymal stem cells. In summary, given their high proliferation activity, immunomodulation, multi-differentiation potential, and the capacity to secrete neuroprotective factors, adult mesenchymal stem cells represent a promising candidate for clinical translation. However, technical hurdles such as optimal dose, differentiation state, route of administration, and the underlying potential therapeutic mechanisms still need to be assessed

    Structure and Dynamics of a Fusion Peptide Helical Hairpin on the Membrane Surface: Comparison of Molecular Simulations and NMR

    Full text link
    The conserved N-terminal residues of the HA2 subunit of influenza hemagglutinin (fusion peptide) are essential for membrane fusion and viral entry. Recent NMR studies showed that the 23-residue fusion peptide forms a helical hairpin that undergoes rocking motion relative to the membrane surface on a nanosecond time scale. To compare with NMR and to obtain a detailed molecular picture of the peptide–membrane interaction, we performed molecular dynamics simulations of the fusion peptide in explicit dimyristoylphosphatidylcholine and with the IMM1 implicit membrane model. To account for low and neutral pH conditions, simulations were performed with acidic groups (E11 and D19) protonated and unprotonated, respectively. The hairpin structure was stable in the simulations, with the N-terminal helix buried more deeply into the hydrophobic membrane interior than the C-terminal helix. Interactions between the tryptophans in the fusion peptide and phospholipid residues contribute to peptide orientation. Higher flexibility of the hairpin was observed in the implicit membrane simulations. Internal correlation functions of backbone N–H vectors were fit to the extended Lipari–Szabo model-free approach to obtain order parameters and correlation times. Good agreement with the NMR results was obtained for orientational fluctuations around the hairpin axis (rotation), but those around the perpendicular axis (tilting) were more limited in the simulations than inferred from the NMR experiments

    Thermodynamic analysis of methanation of palm empty fruit bunch (PEFB) pyrolysis oil with and without in situ CO2 sorption

    Get PDF
    Thermodynamic equilibrium analysis for conversion of palm empty fruit bunch (PEFB) bio-oil to methane using low-temperature steam reforming (LTSR) process was conducted by assuming either isothermal or adiabatic condition, with and without sorption enhancement (SE-LTSR), with CaO(S) or Ca(OH)2(S) as CO2 sorbent. Temperatures of 300-800 K, molar steam to carbon (S/C) ratios of 0.3-7.0, pressures of 1-30 atm and molar calcium to carbon ratios (Ca:C) of 0.3-1.0 were simulated. For reasons of process simplicity, the best conditions for CH4 production were observed for the adiabatic LTSR process without sorption at S/C between 2.5 and 3 (compared to the stoichiometric S/C of 0.375), inlet temperature above 450 K, resulting in reformer temperature of 582 K, where close to the theoretical maximum CH4 yield of 38 wt % of the simulated dry PEFB oil was obtained, resulting in a reformate consisting of 44.5 vol % CH4, 42.7 vol % CO2 and 12.7 vol % H2 and requiring only moderate heating mainly to partially preheat the reactants. Temperatures and S/C below these resulted in high risk of carbon by-product
    corecore