Both experimental investigation and mathematical modeling have been combined to clarify the influence of membrane properties, temperature, electrolyte concentration, and current density on membrane ...resistance of Nafion 117 in concentrated lye solutions. The ionic resistance was measured with and without membrane using four electrodes for 15 wt% and 32 wt% sodium hydroxide, temperatures up to 90 °C, and current densities up to 25 kA/m2. The results from the measurement using Direct Current (DC) method as well as Electrochemical Impedance Spectroscopy (EIS) method indicate that membrane resistance is a function of temperature and lye concentration but is independent of current density. A mathematical model based on the Maxwell-Stefan approach has been developed to predict the ionic membrane resistance, and the model has been validated using the measured experimental data. A more suitable semi-empirical correlation for Maxwell-Stefan diffusivities is proposed by replacing the expressions for binary diffusivities based on infinite dilution with the concentration-dependent binary diffusivities. The new proposed correlation performs better in the model validation with the experimental data than the expressions using infinite dilution diffusivities.
•The ionic membrane resistance of Nafion 117 is measured as a function of temperature, concentration, and current density.•A Maxwell-Stefan model is developed, and the model is validated with the measured resistance.•A more suitable semi-empirical correlation for Maxwell-Stefan diffusivities is proposed.•Both the model and the experiment show that membrane resistance is independent of current density.
A mathematical model based on a generalized Maxwell–Stefan equation has been developed to describe multicomponent ion and water transport inside a cation-exchange membrane. This model has been ...validated using experimental data and has been used to predict concentration profiles, membrane potential drop, and transport numbers of ions and water for the chlor-alkali process at increased current densities. Several improvements have been made to previously developed Maxwell–Stefan models. In our model, the generalized Maxwell–Stefan equation is written in terms of concentration instead of mole fraction and the fixed group (membrane) concentration is assumed to be constant. We have adapted the Augmented matrix method using the built-in partial differential equation parabolic elliptic (pdepe) solver in Matlab®, and both the concentration and the electrical potential gradients have been solved simultaneously. The boundary conditions are determined with the Donnan equilibrium at the membrane–solution interface. We have also employed semi-empirical correlations to define the Maxwell–Stefan diffusivities inside the membrane. For the bulk diffusivities, we applied the correlations for the concentrated solution instead of the values at infinite dilution. With the diffusivities presented in this work, the model shows a better fit to the experimental data than with previously reported fitted diffusivities. Prediction of the sodium transport number and water transport number is generally good, whereas the deviations with regard to membrane potential might also be related to issues with the experimental data. The model predicts an increase in both sodium and water transport numbers at increased current density operation of chlor-alkali production.
Graphical abstract
The Gender Development Index in Indonesia, released by the Ministry of Women’s Empowerment and Child Protection of the Republic of Indonesia in 2020, ranked West Nusa Tenggara Province as the lowest ...nationally. These statistical data show that West Nusa Tenggara’s position nationally is still far behind other provinces in Indonesia. On the other hand, as a province led by a female Vice Governor, West Nusa Tenggara Province has a strategic role in the representation of women in the bureaucracy. Women leaders are expected to play a role in strategic issues related to the gender development index with an active representative bureaucracy. However, the active representation of women in local (provincial) government is still very small, especially in the context/situation of regions with patriarchal characteristics. Furthermore, research with phenomenological approaches/methods is still very rare. This study used phenomenological methods. The subjects of this study are female regional leaders, namely the Vice Governor of NTB Province. The data collection technique used is in-depth interviews and reviewing secondary documents that support the active representation of women in the bureaucracy in the field of education in West Nusa Tenggara Province. The data processing and analysis techniques in this study used technical narrative analysis, which was carried out in several stages such as making interview transcripts and interpreting the meaning of the information obtained by coding techniques, analyzing certain transcripts to then be classified into several themes to identify information that is by the theme and concluding meaning relevant to the research theme. The results of this study show that the importance of women’s leadership initiatives to the interests of women has a huge impact on women themselves. Special needs are becoming more of a concern and are considered as important as other development priorities. This is possible with the active repression of female leaders.
Keywords: Active Representative Bureaucracy, women’s participation, women’s leader initiative, West Nusa Tenggara
Dengue is hyperendemic in Indonesia. In 2015, reported cases of dengue fever doubled those of 2014 in the Jambi municipality of Sumatra. We examined viral aetiology and its relationship with disease ...outcome in Jambi. Dengue-suspected patients' sera were collected and NS1 detection and IgM/IgG serology were performed. Dengue virus (DENV) serotyping was performed using real-time RT-PCR. Envelope genes were sequenced to determine the genotypes of DENV. Clinical, haematologic, and demographic data were recorded. Of 210 dengue-suspected patients, 107 were confirmed. The disease manifested as Dengue Fever (62%), Dengue Haemorrhagic Fever (36%), and Dengue Shock Syndrome (2%). The serotypes of 94 DENV were determined. All DENV serotypes were detected with DENV-1 as the predominant serotype (66%). Genotypically, the DENV-1 viruses belong to Genotype I, DENV-2 was of Cosmopolitan genotype, DENV-3 as Genotype I, and DENV-4 belonged to Genotype II. Comparison with historical data revealed serotype predominance switched from DENV-3 to DENV-1, and the replacement of Genotype IV of DENV-1 with Genotype I. In summary, DENV-1 predominated during the 2015 dengue outbreak in Jambi. The full spectrum of dengue disease occurred and was characterized by a switch in predominant serotypes.
The correlation between nutritional habits and gut health directly impacts the gut-brain axis via a complex and not yet fully disclosed communication network. Establishing a link between our food ...intake and specific physiological responses as well as a better knowledge of diseases and the gut microbiota involves solving a challenging puzzle of biochemical pathways. Our understanding is limited by the inaccessibility of the gastrointestinal region to routine non-invasive chemical analysis. Here, we move a step further toward the direct assessment of a protein fermentation product, i.e., ammonium ions, via Ion Selective Electrodes (ISEs) in gastrointestinal digesta samples. By modulating the digestible protein content of the diet regimes of two groups of pigs, we discriminate the level of protein fermentation with a straightforward quasi-invivo detection method which does not require any sample preparation. Our results show more than a 2-fold increase in ammonium ion concentration (from 180 ppm to 400 ppm) in the proximal colon for a diet based on poorly digestible proteins compared with a diet based on easily digestible proteins. Our approach shows good correlation with a standard laboratory technique for the determination of NH4+, i.e., the Indophenol Blue Method. Our results show the direct sensing of a protein fermentation product in a real matrix and demonstrate the great potential of potentiometric sensors to assess ammonium concentration profiles along the gastrointestinal tract for diets varying in protein digestibility and fermentation.
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•Electrochemical sensors are applied directly in gastrointestinal digesta without any sample preparation.•A potentiometric method distinguishes two dietary regimes by sensing distinct NH4+ profiles along the gastrointestinal tract.•A clear link between nutritional interventions and the resultant physiology of the gastrointestinal tract is demonstrated.
Abstract
Tapanuli orangutan is an endemic animal in North Sumatra that must be protected so that conservation efforts are needed to preserve it. Tapanuli Orangutan nests are the focus of this ...research. This research is aimed to know the variety of constituents plant the nests of tapanuli orangutan (
Pongo tapanuliensis
), to know the kind of the most dominant plant to construct the nests by Tapanuli orangutan (
Pongo tapanuliensis
), the composition of constituents the nests of tapanuli orangutan (
Pongo tapanuliensis
) in North Tapanuli. This research was primery forest Batang Toru National Park. This research using line transect method with 4 transects (transects I, II, III, IV) were used to observe the nest tree and the nest constituent of Tapanuli orangutan. This research results is there are 5 species of of constituents plant the nests with quantity 14 nests. The most dominant tree nest is
Syzygium
sp (43%), Plant constituent orangutan nests also use the leaves of the
Shorea hopeifolia
(94.1%), as well as branches of
Palaquium gutta
(6.6%).
This research aims to examine the effect of Artemisin and Moringa oleifera leaf extract combination on the percentage of CD4+ and CD8+ T cell of mice infected with P.berghei. CD4+ and CD8+ T cells ...have important role in eliminating Plasmodium intracellular parasite that causes malaria infection. Artemisin is a potent antimalarial that kills the parasite through free radicals production. Excessive free radicals damage the immune cells, including CD4+ and CD8+ T cells. Flavonoid (quercetin and kaempferol) bioactive on Moringa leaves is a powerful antioxidant and anti-inflammatory, and is expected to prevent and decrease the adverse effects of Artemisin. This experimental post-test group research was conducted on six groups, i.e. normal mice (negative control), P.berghei infected mice without treatment (positive control), and four other groups, i.e. P.berghei infected mice and treated with Artemisin 0.004mg/gBW (A), and combinations of Artemisin 0.004mg/gBW and Moringa leaf extract 0.125mg/gBW (DK1), 0.250mg/gBW (DK2), and 0.500mg/gBW (DK3). On day 3 and 7, blood samples from each group were drawn randomly, parasitemia degree was calculated microscopically (magnification 1000 times), the percentage of CD4+ and CD8+ T cells was determined using flowcytometry. The results of this study indicated that the administration of Artemisin and Moringa leaf extract combination for 7 days significant increased the percentage of CD4 + T cells in DK2 (p=0.001) and DK3 (p=0.000), and decreased the degree of parasitemia in DK1 (p=0.000), DK2 (p=0.000), and DK3 (p=0.000), however CD8 + T cells show no difference. There was a relationship between Artemisin and Moringa leaf extract combination with the degree of parasitemia (p=0.000) and the percentage of CD4+ T cells (p = 0.000), but not on CD8+ T cells. Keywords: parasitemia, CD4+ and CD8+ T cells, Moringa oleifera
Penelitian yang dilakukan penulis adalah untuk menguji pengaruh capital adequency ratio (CAR), loan to deposit ratio (LDR) terhadap return saham perbankan BUMN dimediasi oleh Nilai Perusahaan. ...Diharapkan penelitian ini mampu memberikan manfaat, meningkatkan dan memaksimalkan kinerja perbankan. Penulis menggunakan metode penelitian deskriptif dengan data yang digunakan adalah data kuantitatif. Penelitian ini menggunakan metode analisis regresi linier berganda dengan menggunakan bantuan software IBM SPSS versi 26 . Dari analisis penelitian diperoleh hasil jika Nilai perusahaan atau PBV dapat menjadi memediator terhadap pengaruh CAR, terhadap return saham perbankan BUMN di Indonesia. Namun nilai perusahaan atau price to book value (PBV) tidak mampu menjadi mediator pengaruh LDR terhadap return saham perbankan BUMN di Indonesia. Hal ini menunjukkan jika Nilai perusahaan atau PBV memiliki peran penting menjadi penghubung pengaruh variable independen terhadap variable dependen. CAR dan LDR tidak dapat mempengaruhi return saham perbankan BUMN secara langsung.
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