352 research outputs found
Exploring Uniting Factor for Multiculturalism Policy: Portrait of Hadrami, Arab Community in Indonesia
In the 2nd International Symposium of Anthropology held by FISIP-UI in 2002 in Padang, a participant questioned: ”As Pancasila no longer has the power as a uniting factor for ethnic diversity in Indonesia, what factor then has the same power as Pancasila for multiculturalism policy in this country.” (This paper is not intended to discuss Pancasila, but to explore the unifying factor, instead
Studi Eksperimental Pengaruh Model Sistem Saluran dan Variasi Temperatur Tuang terhadap Prosentase Porositas, Kekerasan dan Harga Impact pada Pengecoran Adc 12 dengan Metode Lost Foam Casting
Metode pengecoran lost foam merupakan metode yang tergolong baru dalam industri pengecoran logam. Pada saat ini belum banyak industri pengecoran logam yang menggunakan metode ini dalam memproduksi benda cor. Sedikitnya industri yang menerapkan metode pengecoran ini, yang mendorong untuk melakukan percobaan pengecoran dengan menggunakan metode lost foam, dengan melakukan perbedaan variasi temperatur tuang dan variasi model sistem saluran. Proses pengecoran dengan metode lost foam ini menggunakan styrofoam sebagai polanya, yang ditanam dalam cetakan yang berisi pasir silika kering (tanpa pengikat) kemudian cetakan digetarkan untuk memadatkan pasir. Ketika logam cair dimasukkan ke dalam cetakan, maka styrofoam akan menguap sampai cetakan tersebut terisi penuh oleh logam cair. Dalam penelitian ini, parameter yang digunakan adalah model sistem saluran dan variasi temperatur tuang terhadap kualitas hasil coran, diantaranya kekerasan, harga impact, prosentase porositas dan struktur mikro. Material yang digunakan dalam pengecoran ini adalah ADC (Aluminium Die Casting) 12. Parameter pertama yaitu model sistem saluran meliputi saluran samping, saluran bawah, saluran bawah dengan 2 gate dan saluran bawah dengan 3 gate dengan temperatur tuang konstan 700°C. Parameter kedua yaitu variasi perbedaan temperatur tuang antara 700°C, 750°C, 800°C dan 850°C dengan sistem saluran samping. Dari hasil penelitian ini diperoleh bahwa sistem saluran samping memiliki prosentase cacat porositas paling sedikit dibanding sistem saluran lainnya yaitu sebesar 2,7535% dan memiliki harga impact rata-rata paling besar yaitu 0,0275 J/mm2 pada potongan 1 dan 0,0660 J/mm2 pada potongan 2. Variasi temperatur tuang berpengaruh terhadap banyaknya cacat porositas dan harga impact rata-rata. Temperatur tuang 700°C dibanding temperatur tuang yang lain memiliki cacat porositas paling sedikit dan harga impact rata-rata paling besar yaitu 0,0275 J/mm2 pada potongan 1 dan 0,0660 J/mm2 pada potongan 2. Namun dari hasil pengujian kekerasan baik pada parameter model sistem saluran dan variasi temperatur tuang tidak dapat menunjukan perbedaan yang jelas
Minimizing the Age of Information in Wireless Networks with Stochastic Arrivals
We consider a wireless network with a base station serving multiple traffic
streams to different destinations. Packets from each stream arrive to the base
station according to a stochastic process and are enqueued in a separate (per
stream) queue. The queueing discipline controls which packet within each queue
is available for transmission. The base station decides, at every time t, which
stream to serve to the corresponding destination. The goal of scheduling
decisions is to keep the information at the destinations fresh. Information
freshness is captured by the Age of Information (AoI) metric.
In this paper, we derive a lower bound on the AoI performance achievable by
any given network operating under any queueing discipline. Then, we consider
three common queueing disciplines and develop both an Optimal Stationary
Randomized policy and a Max-Weight policy under each discipline. Our approach
allows us to evaluate the combined impact of the stochastic arrivals, queueing
discipline and scheduling policy on AoI. We evaluate the AoI performance both
analytically and using simulations. Numerical results show that the performance
of the Max-Weight policy is close to the analytical lower bound
MANAGERIAL PERCEPTION TOWARD HALAL CERTIFICATION: STUDY OF INTERNATIONAL FOOD CHAINS IN PAKISTAN
Halal certification studies in hospitality industry are rarelyexplored and discussed. In particular, research on Halal certificationin Pakistan is yet to be explored. Recently realizing the potential ofHalal food market, the Ministry of Science and Technology hasestablished Halal Authority. In this context, this study explores themanagerial perception of International Food Chains (IFCs) towardshalal certification in Pakistan. Further, the impact of halalcertification on restaurant performance is explored. In this study sixvariables were positively hypothesized whereas two variables werenegatively hypothesized in relation halal certification. For furtherextension, halal certification affect was measured on restaurantperformance. Multiple regression analysis was used to estimate results,showing the acceptance of positively hypothesized relationships andrejection of negatively hypothesized relationships
External Validation of a Single-Item Scale to Measure Motivation to Stop Smoking: Findings from a Representative Population Survey (DEBRA Study)
Aims: The Motivation to Stop Scale (MTSS) is a single-item English language scale for predicting attempts to quit smoking. The aim of the study was an external validation of a German version of the MTSS (Motivation zum Rauchstopp Skala, MRS) based on a sample of current tobacco smokers in Germany. Methods: We used data from the first 18 waves (June 2016-May 2019) of the DEBRA study (German Study on Tobacco Use): a nationwide, face-to-face household survey of persons aged 14 years and older with one follow-up telephone interview after 6 months. We analysed data from 767 current smokers. The MRS was used at baseline (level 1-7 = no to highest motivation). At follow-up, the number of quit attempts since baseline were measured. We conducted logistic regression analyses and calculated the discriminant accuracy of MRS using the Area Under the Receiver Operating Characteristic Curve (ROC-AUC). Results: At baseline, 61.1 % (n = 469; 95 % confidence interval (CI) = 57.7-64.6) of current 767 tobacco smokers were not motivated to quit smoking (MRS level 1-2). Overall, 185 of the 767 smokers (24.1 %; CI = 21.1-27.1) made at least one quit attempt between the baseline and follow-up survey. The odds of reporting a quit attempt increased with increasing motivation to stop smoking on the MRS: odds ratio = 1.37, 95 % CI = 1.25-1.51. The discriminative accuracy of the MRS was ROC-AUC = 0.64. Conclusion: The MRS is a brief and valid measurement for assessing the motivation to stop smoking in the German language
Berry-cluster thinning to reduce compactness of "Black Star" table grapes.
The berry-cluster thinning technique was evaluated at different phenological times to prevent bunch compactness of ?Black Star? table grape, a new somatic mutation of ?Brasil? grape. The trial was carried out during 2012 and 2013 seaons in a vineyard situated in Marialva, PR, Brazil. Vines were trained in an overhead trellis system and spaced at 3x4m. The randomized block design was used as a statistical model with five replications and five treatments. The following treatments were evaluated: control; brushing prior to anthesis; and berry-cluster thinning at different times, when berries were 3-6, 7-10, or 11-15mm in diameter. The prevalence of bunch compactness was evaluated considering the levels: loose, medium loose, and dense bunches. The main physico-chemical characteristics of grapes and yield were also appraised. The data obtained were submitted to ANOVA, and toTukey?s test at 5% was applied. So, thinning is a mandatory practice to avoid bunch compactness of ?Black Star? grapes. The technique has to be performed, preferably, by means of brushing prior to anthesis, and the failure to accomplish this practice at this time, berry-cluster thinning when berries are 11-15mm in diameter can be used. Key words: Vitis vinifera L., grape thinning, cultural practices. RESUMO: O método de raleio de bagas em diferentes fases fenológicas reduz a compactação de cachos da uva fina de mesa ‘Black Star’, uma nova mutação da uva ‘Brasil’. As videiras foram conduzidas em latada em espaçamento 3x4m, e o experimento foi realizado nas safras 2012 e 2013. O delineamento experimental consistiu em blocos casualizados, com cinco repetições e cinco tratamentos: controle sem raleio; raleio com escova plástica realizado no pré-florescimento e; despenca quando as bagas apresentavam 3-6, 7-10 ou 11-15mm de diâmetro. A compacidade predominante dos cachos foi avaliada de acordo com a seguinte classificação: cachos soltos, medianamente soltos e compactos. As características físico-químicas dos cachos e a produtividade também foram avaliadas. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5%. Verificou-se que o raleio de bagas é uma prática obrigatória na uva ‘Black Star’ para diminuir a compacidade dos cachos. A operação deve ser realizada, preferencialmente, com a escova plástica no pré-florescimento, e na impossibilidade de executar ou finalizar essa prática nesta fase, pode-se empregar a despenca quando as bagas apresentarem 11-15mm de diâmetro. Palavras-chave: Vitis vinifera L., raleio de bagas, tratos culturais
Daily supplementation of a multiple micronutrient powder improves folate but not thiamine, riboflavin, or vitamin B <sub>12</sub> status among young Laotian children:a randomized controlled trial
PURPOSE: To assess the effects of intervention with a daily multiple micronutrient powder (MNP) on thiamine, riboflavin, folate, and B(12) status among young Laotian children. METHODS: Children (n = 1704) aged 6–23 mo, participating in a double-blind placebo-controlled randomized trial were individually randomized to receive daily either MNP (containing 0.5 mg of thiamine, 0.5 mg riboflavin, 150 μg folic acid, and 0.9 μg vitamin B(12) along with 11 other micronutrients) or placebo and followed for ~ 36 weeks. In a randomly selected sub-sample of 260 children, erythrocyte thiamine diphosphate (eThDP), plasma folate and B(12) concentrations, and erythrocyte glutathione reductase activation coefficient (EGRac; riboflavin biomarker) were assessed at baseline and endline. RESULTS: There was no treatment effect on endline eThDP concentrations (110.6 ± 8.9 nmol/L in MNP vs. 109.4 ± 8.9 nmol/L in placebo group; p = 0.924), EGRac (1.46 ± 0.3 vs. 1.49 ± 0.3; p = 0.184) and B(12) concentrations (523.3 ± 24.6 pmol/L vs. 515.9 ± 24.8 pmol/L; p = 0.678). Likewise, the prevalence of thiamine, riboflavin, and B(12) deficiencies did not differ significantly between the two groups. However, endline folate concentration was significantly higher in the MNP compared to the placebo group (28.2 ± 0.8 nmol/L vs 19.9 ± 0.8 nmol/L, respectively; p < 0.001), and correspondingly, the prevalence of folate deficiency was significantly lower in the MNP group (1.6% vs 17.4%; p = 0.015). CONCLUSIONS: Compared to a placebo, daily MNP for 9 months increased only folate but not thiamine, riboflavin, or B(12) status in young Laotian children. TRIAL REGISTRATION: The trial was registered at www.clinicaltrials.gov (NCT02428647) on April 29 2015
First-principles modeling of the polycyclic aromatic hydrocarbons reduction
Density functional theory modelling of the reduction of realistic
nanographene molecules (C42H18, C48H18 and C60H24) by molecular hydrogen
evidences for the presence of limits in the hydrogenation process. These limits
caused the contentions between three-fold symmetry of polycyclic aromatic
hydrocarbon molecules and two-fold symmetry of adsorbed hydrogen pairs.
Increase of the binding energy between nanographenes during reduction is also
discussed as possible cause of the experimentally observed limited
hydrogenation of studied nanographenes.Comment: 18 pages, 7 figures, accepted to J. Phys. Chem.
Synthesis, antitubercular activity and mechanism of resistance of highly effective thiacetazone analogues
Defining the pharmacological target(s) of currently used drugs and developing new analogues with greater potency are both important aspects of the search for agents that are effective against drug-sensitive and drug-resistant Mycobacterium tuberculosis. Thiacetazone (TAC) is an anti-tubercular drug that was formerly used in conjunction with isoniazid, but removed from the antitubercular chemotherapeutic arsenal due to toxic side effects. However, several recent studies have linked the mechanisms of action of TAC to mycolic acid metabolism and TAC-derived analogues have shown increased potency against M. tuberculosis. To obtain new insights into the molecular mechanisms of TAC resistance, we isolated and analyzed 10 mutants of M. tuberculosis that were highly resistant to TAC. One strain was found to be mutated in the methyltransferase MmaA4 at Gly101, consistent with its lack of oxygenated mycolic acids. All remaining strains harbored missense mutations in either HadA (at Cys61) or HadC (at Val85, Lys157 or Thr123), which are components of the bhydroxyacyl-ACP dehydratase complex that participates in the mycolic acid elongation step. Separately, a library of 31 new TAC analogues was synthesized and evaluated against M. tuberculosis. Two of these compounds, 15 and 16, exhibited minimal inhibitory concentrations 10-fold lower than the parental molecule, and inhibited mycolic acid biosynthesis in a dose-dependent manner. Moreover, overexpression of HadAB HadBC or HadABC in M. tuberculosis led to high level resistance to these compounds, demonstrating that their mode of action is similar to that of TAC. In summary, this study uncovered new mutations associated with TAC resistance and also demonstrated that simple structural optimization of the TAC scaffold was possible and may lead to a new generation of TAC-derived drug candidates for the potential treatment of tuberculosis as mycolic acid inhibitors
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