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A comparison of the amine-modified silica particle’s characteristics via ex- and in-situ routes and their application as a CO2 gas adsorbent is reported. Modifying silica particles via ex-situ involves two separate steps: forming porous silica particles with sodium lauryl sulfate (SLS) as a template and impregnation using ultrasound assistance. In contrast to ex-situ modification, in-situ modification of silica particles is carried out in one step by mixing directly between the silica source and the modifying agent. Controlling the characteristics of modified silica particles via in-situ is carried out by adding an SLS template removed simultaneously with particle formation to increase the surface area and porosity. Increasing the SLS template concentration shows a linear relationship between increasing particle surface area and amine loading. However, two different modification routes exert a direct influence on aminopropyl distribution. Silanization via in-situ which involves a simultaneous condensation reaction produces a higher amine loading reaching 1.2845 mmol/g of silica than via ex-situ which is only 0.9610 mmol/g of silica. The amount of aminopropyl that can be grafted on the silica surface shows a linear relationship to the quantity of CO2 gas adsorption capacity. Amine-modified silica particles obtained the highest adsorption capability via the in-situ route with an SLS 3 CMC template of 2.32 mmol/g silica at an operating pressure of 6 bar.

Gold is one of the most attractive commodities and popular investments. Investment experts often recommend investing in gold because gold is one of the safest investments. It is a stable classic hedge, although the conditions of currency volatility or global markets are depreciated. However, the gold price fluctuations can be influenced by some other factors, such as the USD Index, which reflect and measure the strength of the US Dollar currency, and the Index of Dow Jones Industrial Average (DJIA) or a reflection of the political and economic conditions of the stock market. In this study, we conduct a global gold price forecast (USD) based on the USD Index, the DJIA Index, and the influence of time trends. Based on the data's characteristics, we face the fact that the data is nonlinear, contains outliers, and its pattern is not easy to specify parametrically. Due to the complexity of the model, we then propose a more flexible, robust modeling technique called the Bayesian Nonparametric Quantile Generalized Additive Model method. According to the results for the median case, the proposed method shows an accurate forecasting category due to the value of the Mean Absolute Percentage Error, MAPE less than 10 percent.

The high demand for supercapacitors has led to the importance of developing low-cost and eco-friendly materials. Instead of powders, nanofibers were widely developed as a carbon source to increase their durability and ease of handling. Herein, we report the effect of dispersed activated carbon derived from coconut shell charcoal on the supercapacitor performance of activated carbon nanofibers (ACNFs) by electrospinning. The solution was formed by blending coconut shell charcoal (CSC)-based activated carbon and polyvinyl alcohol (PVA) as a spinning polymer agent. This synthesis was conducted using various concentrations of activated carbon and introducing a surfactant during the process. The electrospinning was held at a 10 kV DC voltage, followed by iodine treatment, thermal stabilization, and carbonization at 800 °C. The highest surface area of 250.46 m2/g was obtained from the ACNFs 25S, consisting of PVA 15 w/v %, CSC 25 wt%, and an anionic surfactant. The electrochemical measurement was conducted using Cyclic voltammetry (CV) and possessed a specific capacitance of 186.50 F/g. Moreover, the ACNFs with dispersed activated carbon are promising to be a high capacitance, low cost, and renewable, thereby representing material toward high-power, environmentally friendly, and renewable energy storage devices through further exploration.

Highlights: 1. Most malaria infections found in East Kutai Regency were found within the male group and had high contact with forest areas. 2. Malaria infections were found predominantly in the male group aged 25 to 34 years old. 3. Most of the malaria infections found were caused by Plasmodium vivax. Abstract: Background: Malaria is endemic in Indonesia and knowing the factors that are involved in malaria infection will help the development of surveillance, prevention, and disease control. Objective: This study aimed to identify the profile of malaria infection and the vectors known in East Kutai Regency, Indonesia, in 2016. Material and Method: This research was a descriptive observational study with a cross-sectional design. The sample used was taken from the 2016 annual report of The Health Office, East Kutai Regency. We evaluated malaria indicators, disease distribution, incidence (age, sex, and occupation), plasmodium species found and known vectors. Result: In 2016, there were 55 confirmed cases of malaria infection in East Kutai. The Annual Parasite Index was 0.16 per 1,000. Malaria patients were dominated by males (85.5%), aged between 25-34 years old with a mean age of 29.56 years. Most of the patients lived in Rantau Pulung (41.8%). Most of the patients had work that had high contact with forest areas (70.9%). Most of the patients were infected with Plasmodium vivax (58.2%). Identified vectors were Anopheles balabacensis which was found in Kaliorang District. Conclusion: The East Kutai Regency was classified as Low Case Incidence Area with most cases found in males of 24 to 34 years old whose work had high contact with forest areas. The identified plasmodium species were Plasmodium vivax and Plasmodium falciparum while the identified vector was Anopheles balabacensis.

One of the most commonly encountered issues in large cities is air pollution. As a major city, Bandung also experiences the same problem. This issue arises due to the increasing levels of human activity. This contributes to elevated levels of pollutants in the atmosphere, which can impact human life and ecosystems. This research is intended to map the regions in Bandung based on their air quality. This study used ambient air quality measurement results from Bandung, which included PM10, PM2.5, dust, SO2, CO, and NO2. This ambient air quality measurement was conducted by the Department of Environment and Hygiene in Bandung. The research methodology utilized in this study was multidimensional scaling analysis. The outcomes of the examination carried out utilizing the multidimensional scaling technique reveal a clustering of regions in Bandung, West Java, based on their air quality. According to the research findings, the locations were grouped into four quadrants, each with different air quality characteristics. Some locations showed high similarity, while others did not exhibit similarity with other groups. These findings can be used for policy-making and improving air quality in Bandung. Conclusions were drawn from the formed groups, where each group had high similarity among its members, but differed from the members of other groups. Among all observed locations in Bandung City, there were areas that were most similar when viewed based on the distance between objects, namely Punclut St. and KPAD Sarijadi; Soekarno Hatta St. (in front of Astra Bizz) and Elang St.; and Buah Batu St. (in front of STSI/ISBI) and Bunderan Cibiru.

Background Oral candidiasis (OC) is an oral mucosal disorder due to Candida genus. Its predisposing factor among patients with HIV/AIDS is mainly decreasing CD4 count. OC is commonly caused by Candida albicans. As CD4 decreases, the shift to C. non-albicans has been observed. Objective To evaluate the association of Candida species with CD4 count and clinical features in HIV/AIDS patients with OC. Patients and methods This is a cross-sectional study. A total of 114 oral rinse solution samples from HIV/AIDS patients with OC were collected. Candida species identification was done by culture in Chromagar followed by VITEK 2. The association of Candida species with CD4 count and clinical features was analyzed using Pearson’s χ2 and Kruskal–Wallis tests. Results There was growth of 149 isolates in culture from 114 patients. C. albicans was found in 104 (69.7%) isolates. Candida non-albicans were found in 45 (30.3%) isolates, namely Candida krusei in 22 (14.85%), Candida glabrata in 12 (8.1%), Candida tropicalis in six (4.05%), Candida dubliniensis in two (1.3%), Candida parapsilosis in two (1.3%), and Candida lipolytica in one (0.7%) isolate. Candida species was significantly associated with clinical types, episode types, pain on swallowing, CD4 count, and antiretroviral (ARV) use among all patients. Conclusion Among HIV/AIDS patients with OC, growth of C. albicans only was more common in higher CD4 count, while mixed growth of C. albicans and C. non-albicans was more common in lower CD4 count. Clinical features associated with growth of C. albicans only were pseudomembranous type, recurrent OC, absence of pain on swallowing, and patients on ARV, whereas those associated with mixed growth of C. albicans and C. non-albicans were cheilitis type, first-episode OC, presence of pain on swallowing, and ARV-naive patients.

Abstract Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a group of X-linked, hereditary genetic disorders caused by mutations in the G6PD gene and results in functional variants of about 400 biochemical and clinical phenotypes. Among them, more than 215 genotypes have been identified so far. In this review, specific features of the genotype distribution in different communities and countries are discussed based on multiple reports and our molecular epidemiological studies of Southeast Asian countries. Particularly, in Indonesia, the frequency distribution of G6PD deficiency variants was distinct between western and eastern Indonesian populations, suggesting two different gene flows during Indonesian expansions.

ABSTRACT Soil-Transmitted Helminths (STH) infection is the most common intestinal parasite infection in Indonesia. STH infection can interfere with child development and cause cognitive impairment in severe cases. The school-age group is the most susceptible to STH infection because of direct contact with soil in the school yard. STH infection incidence can be avoided by adequate water, healthy latrines, and good hygiene and can be improved by proper interventions. This study aimed to analyze the correlation between Water, Sanitation, and Hygiene (WASH) with STH infection in Aru Islands District, Maluku. This study used a cross-sectional design and was conducted in Elementary Schools in Karangguli and Wokam villages, Aru Islands district, Maluku. One hundred and six stool samples were collected from both villages. The sociodemographic and WASH data were collected using the interview method. Stool samples were collected and examined for STH infection using a direct smear technique on the light microscope. Data statistical analysis was performed by the SPSS program using the Chi-square or Fischer’s Exact test. The examination results showed that 73 students (68.9%) were infected with STH. The bivariate analysis showed that water source (p = 0.000002), defecation place (p = 0.002), and washing hands after defecation (p = 0.048) were all significantly correlated with STH infection. This study concluded that WASH variables which were water source, defecation place, and washing hands after defecation had a significant correlation with STH infection. Keywords: Water, Sanitation, and Hygiene (WASH); soil-transmitted helminths infection; elementary school students.

The cigarette commodity is the second largest contributor to the food poverty line. Several aspects imply that poor people consume cigarettes despite having a minimal income. In this study, we are interested in investigating factors influencing poor people to be active smokers. Since the consumption number is a set of count data with zero excess, we have an overdispersion problem. This implies that a standard Poisson regression technique cannot be implemented. On the other hand, the factors involved in the model need to be selected simultaneously. Therefore, we propose to use a zero-inflated negative binomial (ZINB) regression with a minimax concave penalty (MCP) to determine the dominant factors influencing cigarette consumption in poor households. The data used in this study were microdata from the National Socioeconomic Survey (SUSENAS) conducted in March 2019 in East Java Province, Indonesia. The result shows that poor households with a male head of household, having no education, working in the informal sector, having many adult household members, and receiving social assistance tend to consume more cigarettes than others. Additionally, cigarette consumption decreases with the increasing age of the head of household.

The problem of crude oil reserve shortage and air quality decline currently have led researches on renewable fuel such as bioethanol and biohydrogen. The attempt to provide such biofuel involves the utilization of enormously available wasted materials, lignocellulose. Coconut husk is one of such materials available in Indonesia. The previous work had reported the quantity of total reducing sugar produced after the enzymatic hydrolysis of pretreated coconut husk. The pretreatment methods used were dilute sodium hydroxide solution (1 and 4% w/v), 1,3-methylmethylimidazolium dimethyl phosphate ionic liquid and the combination of both methods. This work focused on constructing the mathematical model which describes the kinetic of those enzymatic hydrolysis reactions. Mathematical model expressions help describing as well as predicting the process behavior, which is commonly needed in the process design and control. The development of mathematical model in this work was done based on the total reducing sugar concentration resulted in batch hydrolysis reaction. The kinetic parameters including initial available substrate (S0), maximum reaction rate (rmax), and half-maximum rate constant (KM). According to the values of half-maximum rate constant (KM), the enzymatic hydrolysis performance of coconut husk treated using ionic liquid is better than that treated using dilute alkaline solution as the former had shown lower KM value and hence higher enzyme affinity to the substrate. The best hydrolysis result was performed using combination of 1% dilute sodium hydroxide solution and ionic liquid with kinetic model parameter of 0.5524 g/L.h of rmax, 0.0409 g/L of KM, and 4.1919 g/L of S0. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Generally, modeling poverty aims to obtain the best criteria for assessing poverty status. There are two approaches to model the factors that affect poverty, namely consumption approach and discrete choice model. The advantage of the discrete choice model compared to the consumption approach is that the discrete choice model provides a probabilistic estimate for classifying samples into different poverty categories. This study aims to examined how the factors that affect poverty in Yogyakarta through Regularized Ordinal Regression with elastic net approach both for parallel, non-parallel, and semi-parallel models. The data used in this study is Susenas March 2018 for Yogyakarta provinces. The result of this study shows that the best discrete choice model for Yogyakarta’s modelling is the parallel model. Households that live in villages, have a large number of household members, are headed by women, have elderly household heads, have low education, and work in the primary sector tend to be more vulnerable to poverty. Therefore, a simultaneous policy with inclusive economic development is needed to reduce cross-border, cross-gender, and cross-sector inequality

Space-time varying coefficient models, which are used to identify the effects of covariates that change over time and spatial location, have been widely studied in recent years. One such model, called the quantile regression model, is particularly useful when dealing with outliers or non-standard conditional distributions in the data. However, when the functions of the covariates are not easily specified in a parametric manner, a nonparametric regression technique is often employed. One such technique is the use of B-splines, a nonparametric approach used to estimate the parameters of the unspecified functions in the model. B-splines smoothing has potential to overfit when the number of knots is increased, and thus, a penalty is added to the quantile objective function known as P-splines. The estimation procedure involves minimizing the quantile loss function using an LP-Problem technique. This method was applied to upper respiratory tract infection data in the city of Bandung, Indonesia, which were measured monthly across 30 districts. The results of the study indicate that there are differences in the effect of covariates between quantile levels for both space and time coefficients. The quantile curve estimates also demonstrate robustness with respect to outliers. However, the simultaneous estimation of the quantile curves produced estimates that were relatively close to one another, meaning that some quantile curves did not depict the actual data pattern as precisely. This suggests that each district in Bandung City not only has different categories of incidence rates but also has a heterogeneous incidence rate based on three quantile levels, due to the difference in the effects of covariates over time and space.

This research aims to find out the influence of growth sales and operating cash flow on price shares in the company's property, real estate, and building construction listed on the Indonesia Stock Exchange for the 2017-2019 period. The factors tested in this research are growth sales and operating cash flow as variable independent, whereas price share is the dependent variable. The research method used in this research is descriptive. The population in this study is company property, real estate, and building construction registered on the Indonesian Stock Exchange for the 2017-2019 period, totaling 84 companies. The sampling technique used in this research is non-probability sampling method - purposive sampling, so the sample in this study is 46 companies. Multiple linear regression analyses were conducted to assess the extent to which sales growth and operating cash flow impact stock price variations. The results indicate that both sales growth and operating cash flow significantly influence price shares. Furthermore, the analysis reveals that sales growth and operating cash flow collectively account for approximately 45.5% of the variability observed in price shares. [ABSTRACT FROM AUTHOR]

Preventing the further degradation of monomeric or oligomeric sugar into by-product during biomass conversion is one of the challenges for fermentable sugar production. In this study, the performance of subcritical water (SCW) and enzymatic hydrolysis of coconut husk toward reducing sugar production was investigated using a severity factor (SF) approach. Furthermore, the optimal condition of SCW was optimized using response surface methodology (RSM), where the composition changes of lignocellulose and sugar yield as responses. From the results, at low SF of SCW, sugar yield escalated as increasing SF value. In the enzymatic hydrolysis process, the effect of SCW pressure is a significant factor enhancing sugar yield. A maximum total sugar yield was attained on the mild SF condition of 2.86. From this work, it was known that the SF approach is sufficient parameter to evaluate the SCW and enzymatic hydrolysis of coconut husk. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

After a two-year pandemic, coronavirus disease 2019 (COVID-19) is still a serious public health problem and economic stability worldwide, particularly in the Association of Southeast Asian Nations (ASEAN) countries. The objective of this study was to identify the wave periods, provide an accurate space-time forecast of COVID-19 disease and its relationship to vaccination rates. We combined a hierarchical Bayesian pure spatiotemporal model and locally weighted scatterplot smoothing techniques to identify the wave periods and to provide weekly COVID-19 forecasts for the period 15 December 2021 to 5 January 2022 and to identify the relationship between the COVID-19 risk and the vaccination rate. We discovered that each ASIAN country had a unique COVID-19 time wave and duration. Additionally, we discovered that the number of COVID-19 cases was quite low and that no weekly hotspots were identified during the study period. The vaccination rate showed a nonlinear relationship with the COVID-19 risk, with a different temporal pattern for each ASEAN country. We reached the conclusion that vaccination, in comparison to other interventions, has a large influence over a longer time span.

Coconut husk (CCH) as an abundant agricultural waste in Indonesia has the potential to be utilized for sugar production, which is the intermediate product of biofuel. In this study, subcritical water (SCW) assisted by nitrogen (N2) was developed to enhance the enzymatic hydrolysis of CCH. SCW process was optimized by varying the operation condition: the pressure of 60-100 bar, the temperature of 150-190 °C, and the time of 20-60 min. The SCW-treated solid was subsequently hydrolyzed by utilizing a mixture of commercial cellulase and xylanase enzymes. The result shows that the optimum total sugar yield was obtained under the mild condition of SCW treatment, resulting in the sugar of 15.67 % and 10.31 % gained after SCW and enzymatic hydrolysis process, respectively. SEM and FTIR analysis of SCW-treated solid exhibited the deformation of lignin and solubilization of cellulose and hemicellulose, while XRD and TGA revealed an increase of the amount of crystalline part in the solid residue. The use of N2 in SCW treatment combined with enzymatic hydrolysis in this study suggested that the method can be considered economically for biofuel production from CCH waste in commercial scale. Copyright © 2020 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

The majority of HIV / AIDS patients have common secondary infections including of oral candidiasis. Fluconazole can be used to treat oral resistance in candidiasis. Management that can reduce risk can be minimized. However, some evidences suggest that the use of fluconazole is not effective for oral candidiasis. A 34-year-old male patient went to Dr. Soetomo General Academic Hospital, Surabaya, Indonesia, with main complaint of discomfort and pain in the tongue. The physical examination showed a white pseudomembrane on the tongue and palate, which could be removed but left reddish and painful marks. The examination from tongue and palate swab found a colony of white Candida albicans and showed resistant to fluconazole, intermediate to ketoconazole, and sensitive to nystatin. The patient received nystatin oral suspension for three times a day as much as 5 ml (500,000 units). The pseudomembrane disappeared on day 10. The medication continued for fourteen days. No sign of recurrent found in two weeks after the treatment. The administration of nystatin can be used as an effective medication for oral candidiasis.

Hydrochar was produced from extracted avocado seed using one-step hydrothermal carbonization (HTC) at a temperature of 200 °C for 12 h. The effects of various feedstock solutions on the specific surface area, morphology, pore characteristics, crystallinity, and chemical bonding were investigated to confirm the changes in the electrochemical performances of the produced hydrochar. The presence of potassium permanganate (KMnO _4 ) and ammonia (NH _4 OH) solution in the HTC process successfully produced a porous graphite-like structure of hydrochar with the highest surface area and specific capacitance. Moreover, it also exhibits excellent electrocatalytic performance toward the Oxygen Reduction Reaction (ORR), with a current density of 2.15 mA cm ^−2 via the 2-electron pathway. These results imply that the HTC process can produce hydrochar with high electrocapacitive and electrocatalytic performances even without further activation at high temperatures.

We have previously developed the WST-8 method as a simple and rapid screening test for detection of glucose-6-phosphate dehydrogenase (G6PD) deficiency accomplished by the naked eye. However, it was little difficult to distinguish between faint orange colors developed by heterozygous females and pink colors of normal hemolyzed blood, since both have similar tones. To solve this problem, we established a new and simple screening method that utilizes another formazan substrate, MTT (3-(4,5-dimethyl-2- thiazolyl)-2,5-diphenyl-2H tetrazolium bromide) in combination with a hydrogen carrier, 1-methoxy phenazine methosulfate. MTT formazan exhibits a purple color, thus allowing for the ability to easily distinguish the pink colors of hemolyzed blood. However, MTT has been reported to react with hemoglobin non-specifically and to interfere with the interpretation of the color reaction. In our examinations by mixing MTT with hemolyzed blood, we found that the non-specific reaction was very slow, and that the addition of a small amount of blood (5~10 μl) into a reaction mixture (800 μl) did not interfere with the reaction of G6PD activity. In this new MTT method, a strong purple color was generated in normal blood samples at 20~30 min after incubation, which could be distinguished by the naked eye from G6PD-deficient blood samples with less than 50% residual activity. In addition, quantitative measurement using a spectrophotometer was also possible despite the fact that MTT formazan is water-insoluble.

Detailed information on the flow field in the operation of a mixing unit is necessary for the optimal design of the reactor. The flow field characteristic is an essential factor in obtaining an optimal stirred vessel design. The efficiency of the stirred vessel system depends on, for example, the stirred vessel geometry, the flow induced by the impeller, the working fluid properties and the operating condition. The aim of this study is to exhibit the time-dependent flow field of the mixing process inside a stirred vessel for different propeller rotational speeds using computational fluid dynamics methods. The working fluid in question is molasses and water, which is a miscible liquid. The stirred vessel is a conical-bottomed cylindrical vessel (D = 0.28 m and H = 0.395 m) equipped with a three-blade propeller (d = 0.036 m). The transient calculation was conducted using ANSYS Fluent version 18.2. The Mixture multiphase flow model coupled with the Reynolds-averaged Navier-Stokes Standard k-? (SKE) turbulence model was applied to capture the information on the time-dependent flow fields at various propeller rotational speeds inside the stirred vessel. The flow generated by the propeller was compared at 1000 rpm, 1300 rpm and 1500 rpm. The Multiple Reference Frame method was used to solve the moving domain and stationary domain multiple frames case. The results revealed the local velocity, flow pattern, molasses volume fraction value, density gradient distribution, power number and flow number. The profile of all the variables determines the optimal operating conditions for the degree of mixing required.

The main objective of this work was to study the effect of stirrer entry angle on the hydrodynamic characteristic in an agitated tank with side-entry mixer (side-entry mixing tank) using CFD simulation method. For validation purposes, the simulation results were compared with the experimental results. It was found that similar fluid flow between simulation and experiment results qualitatively. The agitated tank system consists of 40 cm diameter cylindrical tank and a three-blades marine propeller having 4 cm diameter. The working fluid was water with a liquid height of 40 cm. Rotational speed varied between 100-400 rpm and stirrer entry angle () 0o, 10o, and 15o (right side). The modeling configurations used in this simulation are RNG Standard k-? model as a turbulence model coupled with Multiple Reference Frame (MRF) for the propeller motion approaching method in a transient condition. The results showed that simulation configuration MRF-RNG k-? gave realistic results to describe the hydrodynamic characteristics in the side-entry stirred tank. This is supported by simulation results that produced similar flow patterns between simulation and experiment qualitatively. In quantitative analysis, at higher rotational speeds the circulation flow that is formed tends to be pushed further from the impeller discharge and this statement is supported by average velocity data experimentally. Average velocity in the tank has a tendency to increase as the ? increases. The predicted average velocity (in m/s) are 0.0175, 0.0185, and 0.0197 at ? 0o, 10o, and 15o respectively in constant rotational speed (400 rpm). Larger ? produced high tangential velocity lead to a strong circulation flow. Further application of this side-entry mixing tank is for large scale reactors and storage tank to maintain the homogeneity of material inside.

The degradation of organic pollutants using photocatalysis is more effective than conventional methods, with ZnO being the most widely used of the various semiconductor materials for application in photocatalysis. Unfortunately, degradation efficiency is inhibited by the electron-hole recombination. The photocatalytic activity of ZnO can be enhanced by adding noble metals, such as Ag nanoparticles. However, the fabrication of ZnO?Ag using liquid-phase processes is complicated and often requires multiple steps. In this study, the effects of Ag content, ranging from 0 to 20 wt%, in the photocatalytic activity of ZnO?Ag nanocomposites are investigated. The nanocomposites were fabricated by a one-step process using flame pyrolysis and with zinc acetate and AgNO3 as the precursors. The nanocomposites were collected using an electrostatic precipitator and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and nitrogen adsorption-desorption of the Brunauer-Emmett-Teller (BET) specific surface area. The XRD results confirm the existence of Ag nanoparticles in the prepared nanocomposites, whose crystallite size was not significantly influenced by the presence of the nanoparticles. The SEM indicated that the morphology of the nanocomposites produced was spherical, with some aggregates. Particle size distribution of the nanocomposites increased with higher Ag content. The photocatalytic activity of the produced nanocomposites, estimated by evaluating the degradation of the methylene blue aqueous solution under UV irradiation, showed that the highest photocatalytic performance was attained when the concentration of Ag was equal to 5 wt%.

Penelitian ini bertujuan untuk mengetahui fenomena pembakaran batubara dimana dimensi alat, distribusi ukuran partikel, dan jenis kualitas batubara menggunakan validasi dari penelitian Wang. Penelitian ini mengarahkan pada simulasi berbasis CFD. Kondisi operasi pada saat simulasi pembakaran dilakukan pada kecepatan bubbling. Metode yang digunakan sebelum melakukan simulasi pembakaran merupakan kelanjutan dari simulasi fluidisasi dimana masih menggunakan geometri 2-D fluidized bed lalu dilakukan meshing, selanjutnya memasukkan persamaan energi. Geometri fluidized bed yang digunakan berbentuk tabung dengan panjang silinder fluidized bed 1370 mm, diameter silinder 152 mm. Bahan yang digunakan pada penelitian ini berupa pulverized coal dengan jenis batubara Bituminous dimana ukuran partikel dianggap polydisperse dengan ukuran partikel 1 mm dan 1,86mm yang masing-masing sebesar 50% fraksi massa dengan kecepatan 0,2 Kg/s dan suhu 1200 K, dan udara luar yang diinjeksikan dengan kecepatan 0,8 m/s dan suhu 300 K. Analisa pengambilan data adalah berupa kontur fase padatan, kontur temperatur pada fase-1 dan fase padatan, fraksi massa produk pembakaran, massa padatan awal dan akhir simulasi dengan time step sebesar 0,0001 detik dan number of time step sebesar 300000. Selanjutnya data tersebut diplot menjadi grafik temperatur terhadap time step dan disajikan dalam setiap 1 menit simulasi selama 5 menit simulasi. This research aims to determine coal combustion’s phenomenon, where the device’s dimension, particle size distribution, and the quality of rank coal which validated Wang’s reseach. This reseach leads on CFD simulation. The operation condition has did in bubbling velocity. This method is a continuation from fluidization simulation which is use 2-D Geometry and then used the meshing method, and enter the energy equation. The geometry of fluidized bed used was tubular cylinder with 1370 mm length and 152 mm. Materials used in this study was pulverized coal with Bituminous coal type which the particle size was considered as monodispers with particle size was 1.43 mm and polydispersed with particle size was 1 mm with 50% mass fraction and 1.86 mm with 50% mass fraction with flow rate 0,2 Kg/s and the temperature is 1200 K, and the outside air are injected in 0,8 m/s and 300 K. The analysis of data retrieval is solid phase contour, temperature contours in phase-1 and solid phase, mass fraction of combustion product, initial solid mass and final solid mass simulation with time step 0,0001 s and the numberof time step 300000. Then the data is plotted into a graph temperature vs time step and presented in 1 minute simulation for 5 minute simulation.

Mixing is one of the critical processes in the industry. The stirred tank is one of the operating units commonly used in the mixing process. Several factors greatly influence the efficiency of the stirred tank, including the stirred-tank design, operating conditions, and working fluid properties. The side-entry stirred tank is widely applied in industry, among others; the processing of crude oil in the refinery industry, water-molasses mixing in the bioethanol industry, pulp stock chest in the pulp and paper industry, and anaerobic digester for biogas reactors. Mixing time is one of the critical parameters used in the design of the stirred tank. This research will model mixing time in a flat bottomed-cylindrical side-entry stirred tank with dimensions D = 40 cm and T = 40 cm using CFD ANSYS 18.2 by applying the Standard κ − ε (SKE) and Realizable κ − ε (RKE) turbulence models. The stirrer used is a three-blade marine propeller d = 4 cm which is an axial type impeller. The phenomenon of mixing in the side-entry stirred tank, qualitatively described through computational prediction results in the form of flow profiles and tracer density change contours locally. Moreover, quantitatively indicated by mixing time validated using experimental data carried out by the conductometry method. The computational prediction shows that the mixing time modeled using the SKE turbulence model shows a similarity level of 68.16%, while the RKE turbulence model shows 31.94%.

Andrographis paniculata tablets (AS201-01) have previously been shown to have potent bioactivity as an antimalarial and to produce no unwanted side effects in animal models. Here, we present the phase 1 clinical trial conducted to evaluate the safety of AS201-01 tablets in healthy volunteers. The study was a randomized, double-blind controlled cross-over, a placebo-controlled design consisting of a 4-day treatment of AS201-01 tablets. A total of 30 healthy human volunteers (16 males and 14 females) were divided into two groups, and each group was given 4 tablets, twice daily for 4 days. Group 1 received AS201-01, while group 2 received placebo tablets. Volunteers were given a physical examination before the treatment. The effects of AS201-01 on random blood glucose, biochemical, and hematological as well as urine profiles were investigated. There were no changes in observed parameters as a result of AS201-01 being administered. Statistical analysis showed no significant difference (p>0.05) between the test and control group regarding hematology profile, biochemical profile, and random blood glucose. Increased appetite and better sleep, which categorized as grade 1 adverse event was reported after treatment with AS201-01 tablet The outcome supports our previous observation that the AS201-01 tablet, given twice a day for 4 days, is safe and nontoxic. [ABSTRACT FROM AUTHOR]

Soil-transmitted helminths infections are major public health problems in developing countries that require fecal contamination of the environment for transmission. The consumption of raw vegetables without proper washing is one of the main routes of parasite transmission. Therefore, this study conducted to detect the kind and prevalence of soiltransmitted helminths contamination in commonly consumed fresh vegetables sold at several traditional markets in Surabaya. 100 fresh vegetable samples consisting of yardlong bean, cabbage, lettuce, and lemon basil were purchased from five traditional markets in Surabaya. Each sample was washed with tap water, water washing examined using flotation method to find soil-transmitted helminths. The overall prevalence of soil-transmitted helminths contamination was 41% (41/100). The most predominant parasite was hookworms (20%), followed by Strongyloides stercoralis larvae (14%) and Ascaris lumbricoides eggs (7%). The highest prevalence of contamination found in lettuce, with 56% prevalence (14/25), while the lowest prevalence of contamination found in yardlong bean with 24% prevalence (6/25). Sequentially, the prevalence of soil-transmitted helminths contamination of fresh vegetable samples from Pabean traditional market (55%), Keputran traditional market (50%), Wonokromo traditional market (50%), Lakarsantri traditional market (35%) and Mulyosari traditional market (15%), respectively. The present study demonstrated that consumption of vegetables with parasite contamination in this area represents a potential route for the transmission of soil-transmitted helminths infection. Therefore, it is necessary for health authorities to educate consumers about the proper washing of vegetables prior to consumption. Preventive methods such as wearing gloves and washing hands after handling vegetables should advocated to sellers who are at risk of acquiring soil-transmitted helminths infection. [ABSTRACT FROM AUTHOR]

One of the most commonly encountered issues in large cities is air pollution. As a major city, Bandung also experiences the same problem. This issue arises due to the increasing levels of human activity. This contributes to elevated levels of pollutants in the atmosphere, which can impact human life and ecosystems. This research is intended to map the regions in Bandung based on their air quality. This study used ambient air quality measurement results from Bandung, which included PM10, PM2.5, dust, SO2, CO, and NO2. This ambient air quality measurement was conducted by the Department of Environment and Hygiene in Bandung. The research methodology utilized in this study was multidimensional scaling analysis. The outcomes of the examination carried out utilizing the multidimensional scaling technique reveal a clustering of regions in Bandung, West Java, based on their air quality. According to the research findings, the locations were grouped into four quadrants, each with different air quality characteristics. Some locations showed high similarity, while others did not exhibit similarity with other groups. These findings can be used for policy-making and improving air quality in Bandung. Conclusions were drawn from the formed groups, where each group had high similarity among its members, but differed from the members of other groups. Among all observed locations in Bandung City, there were areas that were most similar when viewed based on the distance between objects, namely Punclut St. and KPAD Sarijadi; Soekarno Hatta St. (in front of Astra Bizz) and Elang St.; and Buah Batu St. (in front of STSI/ISBI) and Bunderan Cibiru. [ABSTRACT FROM AUTHOR]

Nanostructured zinc oxide (ZnO) was synthesized via a sonochemical method. The effect of the duration of ultrasonic irradiation in a continuous mode on the generated particles was investigated. Additionally, the effect of flowing either air or nitrogen during the sonication process was investigated. Zinc nitrate and ammonia water-based solutions were selected as chemicals without the addition of other surfactants. The generated particles indicated that a wurtzite structure of ZnO in a hexagonal phase was formed with a crystalline size that increased as the ultrasound irradiation time increased. The morphology of the generated ZnO particles could be changed from flowerlike to needlelike structures via continuous ultrasound irradiation over one to two hours, resulting in increases in the particle lengths and decreases in the particle diameters from 200 to 80 nm. Photoluminescence intensity was also increased with increases in the ultrasonic irradiation times. Photoluminescence spectra were also influenced by the atmospheric environment. Two bands centered at 390 and 500 nm were generated under a nitrogen environment. On the other hand, a single wide band with a peak at around 430 nm was found for particles generated under an air environment. It can be applied for light emitting diodes (LED) or laser fabrication with a controlled emitting band.