Sebelas Maret University

About: Sebelas Maret University is a education organization based out in Surakarta, Indonesia. It is known for research contribution in the topics: Population & Public health. The organization has 10901 authors who have published 10832 publications receiving 33057 citations. The organization is also known as: Universitas Negeri Surakarta & Universitas Sebelas Maret.

High caseload of childhood tuberculosis in hospitals on Java Island, Indonesia: a cross sectional study.

Abstract: Background: Childhood tuberculosis (TB) has been neglected in the fight against TB. Despite implementation of Directly Observed Treatment Shortcourse (DOTS) program in public and private hospitals in Indonesia since 2000, the burden of childhood TB in hospitals was largely unknown. The goals of this study were to document the caseload and types of childhood TB in the 0-4 and 5-14 year age groups diagnosed in DOTS hospitals on Java Island, Indonesia. Methods: Cross-sectional study of TB cases recorded in inpatient and outpatient registers of 32 hospitals. Cases were analyzed by hospital characteristics, age groups, and types of TB. The number of cases reported in the outpatient unit was compared with that recorded in the TB register. Results: Of 5,877 TB cases in the inpatient unit and 15,694 in the outpatient unit, 11% (648) and 27% (4,173) respectively were children. Most of the childhood TB cases were under five years old (56% and 53% in the inpatient and outpatient clinics respectively). The proportion of smear positive TB was twice as high in the inpatient compared to the outpatient units (15.6% vs 8.1%). Extra-pulmonary TB accounted for 15% and 6% of TB cases in inpatient and outpatient clinics respectively. Among children recorded in hospitals only 1.6% were reported to the National TB Program. Conclusion: In response to the high caseload and gross under-reporting of childhood TB cases, the National TB Program should give higher priority for childhood TB case management in designated DOTS hospitals. In addition, an international guidance on childhood TB recording and reporting and improved diagnostics and standardized classification is required

Facile synthesis of core–shell structured Si@graphene balls as a high-performance anode for lithium-ion batteries

Abstract: Encapsulating silicon (Si) nanoparticles with graphene nanosheets in a microspherical structure is proposed to increase electrical conductivity and solve stability issues when using Si as an anode material in lithium-ion batteries (LIBs). Currently the main strategies to produce high-quality Si-graphene (Si@Gra) electrodes are (1) chemical vapor deposition (CVD) of graphene grown in situ on Si by hydrocarbon precursors and (2) encapsulating Si with a graphene oxide followed by postannealing. However, both methods require a high-temperature and are costly and time-consuming procedures, which hinders their mass scalability and practical utilization. Herein, we report a Si@Gra composite with a ball-like structure that is assembled by a facile spray drying process without a postannealing treatment. The graphene sheets are synthesized by an electrochemical exfoliation method from natural graphite. The resulting Si@Gra composite exhibits a unique core-shell structure, from which the ball-like morphology and the number of graphene layers in the Si@Gra composites are found to affect both the electric conductivity and ionic conductivity. The Si@Gra composites are found to increase the capacity of the anode and provide excellent cycling stability, which is attributed to the high electrical conductivity and mechanical flexibility of the layered graphene; additionally, a void space in the core-shelled ball structure inside the Si@Gra compensates for the Si volume expansion. As a result, the Si@few-layer graphene ball anode exhibits a high initial discharge capacity of 2882.3 mA h g-1 and a high initial coulombic efficiency of 86.9% at 0.2 A g-1. The combination of few-layer graphene sheets and the spray drying process can effectively be applied for large-scale production of core-shell structured Si@Gra composites as promising anode materials for use in high-performance LIBs.

Material Characterizations of Gr-Based Magnetorheological Elastomer for Possible Sensor Applications: Rheological and Resistivity Properties.

Abstract: Considering persistent years, many researchers continuously seek an optimum way to utilize the idea of magnetorheology (MR) materials to be practically used for everyday life, particularly concerning resistivity sensing application. The rheology and resistivity of a graphite (Gr)-based magnetorheological elastomer (Gr-MRE) were experimentally evaluated in the present research. Magnetorheological elastomer (MRE) samples were prepared by adding Gr as a new additive during MRE fabrication. The effect of additional Gr on the rheological and resistivity properties were investigated and compared with those of typical MREs without a Gr additive. Morphological aspects of Gr-MRE were characterized using field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDX). Rheological properties under different magnetic fields were evaluated using a parallel-plate rheometer. Subsequently, the resistivity of all samples was measured under different applied forces and magnetic fields. From the resistivity evaluation, two relationship curves resistance (R) under different applied forces (F) and different magnetic fields (B) were established and plotted by using an empirical model. It was observed from the FESEM images that the presence of Gr fractions arrangement contributes to the conductivity of MRE. It was also observed that, with the addition of Gr, rheological properties such as the field-dependent modulus can be improved, particularly at low strain amplitudes. It is also demonstrated that the addition of Gr in MRE can contribute to the likely use of force detection in tactile sensing devices.

Great potency of seaweed waste biomass from the carrageenan industry for bioethanol production by peracetic acid-ionic liquid pretreatment

Abstract: Seaweed waste biomass from the carrageenan industry (SWBC) is a potential biomass feedstock for producing sustainable biofuel because it increases the product value and reduces the pollutant risk. Peracetic acid (PAA) followed by ionic liquid (IL) pretreatment has been used to increase the enzymatic saccharification of pretreated SWBC. The SWBC cellulose content was comparable with that of terrestrial biomasses. PAA + 1-hexylpyridinium chloride ([Hpy][Cl]), and PAA + 1-ethyl-3-methylimidazolium diethylphosphate ([Emim][DEP]) pretreatments produced saccharide and unknown oligosaccharide fractions in regenerated water (∼4–6% SWBC cellulose content). For 48 h of saccharification, the untreated SWBC and the SWBC pretreated using PAA followed by [Hpy][Cl], [Emim][DEP] or 1-ethyl-3-methylimidazole acetate ([Emim][OAc]) produced cellulose conversions of 77, 91, 84 and 62%, respectively. The untreated SWBC had a high cellulose conversion, which may be caused by the low lignin and hemicellulose contents of the SWBC. PAA + IL pretreatment could yield pretreated SWBCs with more amorphous cellulose structures, which lead to an almost-complete cellulose conversion.

Analisis Sentimen Masyarakat terhadap Calon Presiden Indonesia 2014 berdasarkan Opini dari Twitter Menggunakan Metode Naive Bayes Classifier

Abstract: Dalam penelitan ini akan dilakukan analisis sentimen masyarakat terhadap calon presiden dan wakil presiden Indonesia 2014 yang diungkapkan melalui jejaring sosial Twitter Ada beberapa tahap untuk melakukan analisis sentimen, diantaranya adalah tahap pengumpulan data, praprocesing data, POS Tagging, ekstrasi opini menggunakan rule based dan klasifikasi opini menggunakan metode Naive Bayes Classifier Hasil dari penelitian ini didapatkan bahwa pasangan capres dan cawapres Prabowo Subianto dan Hatta Rajasa mendapatkan jumlah percakapan 53% dan pasangan Joko Widodo – Jusuf Kalla mendapatkan 47% Sedangkan untuk hasil polaritas sentimen, Prabowo Subianto – Hatta Rajasa mendapatkan 47,7% untuk sentimen positif, 26,4% sentimen negatif dan 25,9% sentimen netral Sedangkan pasangan Joko Widodo – Jusuf Kalla mendapatkan total 37,6% sentimen positif, 34,4% sentimen negatif, dan 27,9 sentimen netral