256 research outputs found

    Pengolahan Limbah Batubara Atau Abu Terbang (Fly Ash) Untuk Pembuatan Genteng Pres Ringan

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    ABSTRAK Produk sisa pembakaran batubara adalah gas (SO3, NO3, CO2), dan abu yang berupa abu terbang (fly ash) dan abu dasar (bottom ash). Abu terbang tidak _mempunyai nilai ekonomi dan bersifat sebagai pencemar lingkungan. Untuk itu perlu dicari altematif pemanfaatan abu terbang agar bahan tersebut dapat berguna. Tujuan penelitian ini adalah mempelajari kemungkinan pemanfaatan abu terbang untuk pembuatan genteng pres ringan dengan inetode perendarnan. Parameter yang diteliti adalah variasi komposisi abu terbang dan variasi waktu perendaman. Hasil yang diperoleh menunjukkan bahwa kondisi terbaik untuk menghasilkan genteng pres ringan tercapai pada perbandingan apur pasir 1: 1, pada komposisi fraksi abu terbang 60% dengan waktu perendaman 24 hari. harga modulus patah 36,8140kg/cm , bulk density 1,6004g/cm , daya serap 16,430% dan kedap air (kering). Sedangkan untuk perbandingan kapur pasir 1 : 2, pada komposisi fraksi abu terbang 50% dengan waktu perendaman 18 hari. Harga modulus patah 27,3818kg/cm , bulk density 1,6550g/cm , daya serap 15,080% dan kedap air (kering). Menurut harga modulus patah, bulk density, dan tahanan terhadap perernbesan air, genteng pres ringan dari abu terbang memenuhi klasifikasi SII No.0447/81 UDC. 0666-74 sebagai genteng beton tipe II

    Synthesis of benzodipyrandiones

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    The reaction of hydroxycoumarins, flavones, isoflavones and chromones with α, β-unsaturated acids, in the presence of PPA has been found to give a number of compounds whose structures have been elucidated on the basis of spectral data and the formation of 2, 4-DNP derivatives

    Transcriptional landscape of the human and fly genomes: Nonlinear and multifunctional modular model of transcriptomes

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    Regions of the genome not coding for proteins or not involved in cis-acting regulatory activities are frequently viewed as lacking in functional value. However, a number of recent large-scale studies have revealed significant regulated transcription of unannotated portions of a variety of plant and animal genomes, allowing a new appreciation of the widespread transcription of large portions of the genome. High-resolution mapping of the sites of transcription of the human and fly genomes has provided an alternative picture of the extent and organization of transcription and has offered insights for biological functions of some of the newly identified unannotated transcripts. Considerable portions of the unannotated transcription observed are developmental or cell-type-specific parts of protein-coding transcripts, often serving as novel, alternative 5′ transcriptional start sites. These distal 5′ portions are often situated at significant distances from the annotated gene and alternatively join with or ignore portions of other intervening genes to comprise novel unannotated protein-coding transcripts. These data support an interlaced model of the genome in which many regions serve multifunctional purposes and are highly modular in their utilization. This model illustrates the underappreciated organizational complexity of the genome and one of the functional roles of transcription from unannotated portions of the genome. Copyright 2006, Cold Spring Harbor Laboratory Press © 2006 Cold Spring Harbor Laboratory Press

    The causes, treatment, and outcome of acute heart failure in 1006 Africans From 9 countries

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    Background: Acute heart failure (AHF) in sub-Saharan Africa has not been well characterized. Therefore,wesought to describe the characteristics, treatment, and outcomes of patients admitted with AHF in sub-Saharan Africa. Methods: The Sub-Saharan Africa Survey of Heart Failure (THESUS–HF) was a prospective, multicenter, observational survey of patients with AHF admitted to 12 university hospitals in 9 countries. Among patients presenting with AHF, we determined the causes, treatment, and outcomes during 6 months of follow-up. Results: From July 1, 2007, to June 30, 2010, we enrolled 1006 patients presenting with AHF. Mean (SD) age was 52.3 (18.3) years, 511 (50.8%) were women, and the predominant race was black African (984 of 999 [98.5%]). Mean (SD) left ventricular ejection fraction was 39.5% (16.5%)... Conclusions: In African patients, AHF has a predominantly nonischemic cause, most commonly hypertension. The condition occurs in middle-aged adults, equally in men and women, and is associated with high mortality. The outcome is similar to that observed in non- African AHF registries, suggesting that AHF has a dire prognosis globally, regardless of the cause

    Effects of TGF-β1 and IGF-1 on proliferation of human nucleus pulposus cells in medium with different serum concentrations

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    BACKGROUND: The low proliferative viability of human nucleus pulposus(NP) cells is considered as a cause of intervertebral discs degeneration. Growth factors, such as TGF-β1 and IGF-1, have been implicated in cell proliferation and matrix synthesis. OBJECTIVE: To investigate the dose-response and time-course effect of transforming growth factorβ1(TGF-β1) and insulin-like growth factor-1(IGF-1) on proliferation of NP cells. STUDY DESIGN: 3-(4,5-dimethylthiazolyl)-2,5-diphenyl-tetrazolium bromide (MTT) is reduced by dehydrogenase in mitochondria of live cells. The proliferative viability of cells corresponds to the amount of MTT reduced, which is measured with an enzyme-linked immunosorbent assay plate reader. In this study, we assessed dose- and time-dependent effects of NP cells to TGF-β1 and IGF-1 in medium with different serum concentrations by MTT assay. METHODS: After release of informed consent, tissue samples of NP were obtained from anterior surgical procedures performed on five donors with idiopathic scoliosis. Isolated cells were cultured in F12 medium supplemented with 10% fetal bovine serum(FBS). Cells were seeded in 96-well plates at 1 × 10(3 )cells/well. After synchronization, medium was replaced by F12 containing 1% or 10% FBS with either single or combination of TGF-β1 and IGF-1. Dose-response and time-course effect were examined by MTT assay. RESULTS: In the presence of 1% FBS, the response to IGF-1 was less striking, whereas TGF-β1 had a remarkably stimulating effect on cell proliferation. In 10% FBS, both of the two growth factors had statistical significant mitogenic effects, especially TGF-β1. The dose-dependent effect of TGF and IGF on cell proliferation was found within different concentrations of each growth factor(TGF-β1 1–10 μg/L, IGF-1 10–100 μg/L). The time-course effect showed a significant elevation three days later. CONCLUSION: TGF-β1 and IGF-1 were efficient to stimulate cell proliferation of human NP cells in vitro with a dose- and time-dependent manner. These results support the therapeutic potentials of the two growth factors in the treatment of disc degeneration

    Gender differences in clinical characteristics and outcome of acute heart failure in sub-Saharan Africa: results of the THESUS-HF study

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    Background: The impact of gender on the clinical characteristics, risk factors, co-morbidities, etiology, treatment and outcome of acute heart failure in sub-Saharan Africa has not been described before. The aim of this study was to evaluate the sex diffe rences in acute heart failure in sub-Saharan Africa using the data from The sub-Saharan Africa Survey of Heart Failure (THESUS-HF). Methods and results: 1,006 subjects were recruited into this prospective multicenter, international observational heart failure survey. The mean age of total population was 52.4 years (54.0 years for men and 50.7 years for women). The men were significantly older (p = 0.0045). Men also presented in poorer NYHA functional class (III and IV), p = 0.0364). Cigarette smoking and high blood pressure were significantly commoner in men (17.3 vs. 2.6 % and 60.0 vs. 51.0 % respectively). On the other hand, atrial fibrillation and valvular heart disease were significantly more frequent in women. The mean hemoglobin concentration was lower in women compared to men (11.7 vs. 12.6 g/dl, p ≤ 0.0001), while the blood urea and creatinine levels were higher in men (p \u3c 0.0001). LV systolic dysfunctional was also seen more in men. Men also had higher E/A ratio indicating higher LV filling pressure. Outcomes were similar in both sexes. Conclusions: Although the outcome of patients admitted for AHF in sub-Saharan regions is similar in men and women, some gender differences are apparent suggesting that in men more emphasis should be put on modifiable life risk factors, while in women prevention of rheumatic heart diseases and improved nutrition should be addressed vigorously

    Opportunities and obstacles to the elimination of malaria from Peninsular Malaysia: knowledge, attitudes and practices on malaria among aboriginal and rural communities

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    <p>Abstract</p> <p>Background</p> <p>Despite continuous efforts by the government and private sectors, malaria is still a public health problem in rural Peninsular Malaysia. This study investigated household knowledge, attitude and practices (KAP) regarding malaria in two malaria endemic communities, forest-aboriginal and rural communities, in the Lipis district of Pahang state, Malaysia.</p> <p>Methods</p> <p>A descriptive cross-sectional study with a semi-structured questionnaire was carried out among 100 and 123 households from forest-aboriginal and rural areas, respectively.</p> <p>Results</p> <p>Knowledge about malaria and its transmission is significantly higher among the rural participants than the aborigines (86.2% vs 76%, p < 0.01). However, use of medicinal plants and beliefs in witchcraft and sorcery in treating febrile diseases were significantly higher among the aboriginal population (p < 0.01). There were no significant differences between the two communities in terms of the knowledge about malaria symptoms, attitudes towards its severity and practices in preventive measures against malaria by using mosquito bed nets. However, the knowledge and practice of different preventive measures to combat malaria, such as insecticide and the elimination of breeding areas, was significantly higher among the rural population than the aborigines (p < 0.001).</p> <p>Conclusions</p> <p>Both communities were aware of malaria as a disease, but knowledge, attitudes and practices were inadequate. Providing efficient health education to people residing in malaria endemic areas would improve their understanding about malaria prevention in order to bring about the elimination of malaria from the country.</p

    Myosin Va binding to neurofilaments is essential for correct myosin Va distribution and transport and neurofilament density

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    The identification of molecular motors that modulate the neuronal cytoskeleton has been elusive. Here, we show that a molecular motor protein, myosin Va, is present in high proportions in the cytoskeleton of mouse CNS and peripheral nerves. Immunoelectron microscopy, coimmunoprecipitation, and blot overlay analyses demonstrate that myosin Va in axons associates with neurofilaments, and that the NF-L subunit is its major ligand. A physiological association is indicated by observations that the level of myosin Va is reduced in axons of NF-L–null mice lacking neurofilaments and increased in mice overexpressing NF-L, but unchanged in NF-H–null mice. In vivo pulse-labeled myosin Va advances along axons at slow transport rates overlapping with those of neurofilament proteins and actin, both of which coimmunoprecipitate with myosin Va. Eliminating neurofilaments from mice selectively accelerates myosin Va translocation and redistributes myosin Va to the actin-rich subaxolemma and membranous organelles. Finally, peripheral axons of dilute-lethal mice, lacking functional myosin Va, display selectively increased neurofilament number and levels of neurofilament proteins without altering axon caliber. These results identify myosin Va as a neurofilament-associated protein, and show that this association is essential to establish the normal distribution, axonal transport, and content of myosin Va, and the proper numbers of neurofilaments in axons
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