65 research outputs found

    Antioksidan dari Daun Sirih Merah (Piper Crocatum)

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    Research on the antioxidant activity testing has been done using red betel (Piper crocatum) leafs in Palu, Central Sulawesi. This research was conducted to determine the IC50 value and antioxidant activity of red betel leafs extracts which has the ability as a natural antioxidant. This research was conducted with an experimental method using an extraction maceration technique, DPPH (1,1-diphenyl-2-pikrilhidrazil) as free radicals, vitamin C as a positive control, UV-Vis spectrophotometer as an antioxidant test equipment with red betel leafs extracts as samples. Samples of red betel leaves were used as much as 30 grams, and the solvent were absolute ethanol. Various concentrations of the red betel leafs extracts were 20 ppm, 40 ppm, 60 ppm, and 80 ppm. Testing of antioxidant activity was done by using a UV-Vis Spectrophotometer and IC50. The results showed that the IC50 value of the red betel leafs (Piper crocatum) extracts was 47.45 ppm. The red betel leafs extract was categorized into a very powerful antioxidant based on IC50 value, where the optimum percentage of red betel leaf extract activity in inhibiting free radical was 81.82%

    Pengaruh Kepemimpinan dan Motivasi Kerja terhadap Komitmen Organisasional Pegawai Pusat Pendidikan Kelautan dan Perikanan

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    Improving public sevice can be achieved by having employees who have high organizational commitment. The purpose of this research is to determine the effect of leadership style and work motivation to organizational commitment on employee of maritime affairs and fisheries education center. The effects were directed to diffrerentiate between transactional & transformational leadership. The sample in this reseach consist of 35 employee of maritime affairs an fisheries education center. The sampling used purposive sampling, data collection methods with questionaires. The data was processed by using Smart PLS with relation of reflective indicator at 95% confidence level. The result shows that the leadership is not significant enough to effect the organizational commitment. Leadership has significantly effect on work motivation, while work motivation has significantly effect on organizational commitment

    Pengaruh Kenaikan Kadar Glukosa Darah Terhadap Peningkatan Daya Ingat Jangka Pendek Pada Wanita Dewasa

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    In Indonesia most people starts their days with eating breakfast.  However, there are still many who do not realize the importance of starting a day with breakfast. Many research suggest that having breakfast can improve short term memory. After breakfast, blood glucose level will raise. It is assumed that glucose plays an important role in improving memory. The purpose of this research is to  find the effect of raised blood glucose level in improving short term memory. In this research Real Prospective Experimental Method and Random Complete Design were used. 30 FK UKM third year female student have been studied, their age range between 19-23 years old, and they were given porridge for breakfast. Blood glucose level was measured before breakfast and 30, 60, 90 minutes afterwards. Short term memory was tested with memory test before breakfast and three times after breakfast. Data was analyzed to analyze the correlation between blood glucose and memory. There are significant increase of blood glucose and memory after breakfast and there is a significant corelation between raised blood glucose and memory. The conclusion is breakfast may improve memory and the raised of blood glucose level matched with the improvement of memory. &nbsp

    Aktivitas Antioksidan Dan Efek Sitotoksik Ekstrak Kola (Cola Nitida) Pada Kulter Sel Kanker Hati (HepG-2)

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    Liver cancer is one among cancers with increasing incidence in the world. Cola fruit (Cola nitida) is a fruit that is rich in properties and has been known since the Dutch colonial era. This fruit contains ingredients such as those contained in tea and chocolate such as methylxanthine and its derivatives. This study aims to determine the content of antioxidants and cytotoxic effects of cola fruit extracts obtained from Indonesia and Malaysia on liver cancer cell lines. Antioxidant content of fruit extracts of cola was assessed using DPPH (2,2-diphenyl-2-picrylhydrazyl hydrate) and cytotoxic effects were studied using MTT (3 - (4,5-Dimethylthiazol-2-Yl)diphenyltetrazolium bromide -2.5) on human liver cancer cell lines (HepG2). The results showed that cola fruit from Malaysia contained high antioxidant with the IC50 value of 37.2 ?g/mL whereas IC50 of value of its Indonesias cola fruit was 66.0 ug / mL. The similar results have been shown in the cytotoxic test using HepG-2 liver cancer cell lines. Malaysias cola fruit extract has a smaller IC50 value of 6.5 ?g / mL while the fruit extract of Indonesias cola showed IC50 value of 39.5 ?g / mL. These values indicates that the fruit extract of cola is a potential anticancer activities especially on liver cancer. Further studies are required to clarify this hypothesis

    Anticancer activity of a sub-fraction of dichloromethane extract of Strobilanthes crispus on human breast and prostate cancer cells in vitro

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    <p>Abstract</p> <p>Background</p> <p>The leaves of <it>Strobilanthes crispus </it>(<it>S. crispus</it>) which is native to the regions of Madagascar to the Malay Archipelago, are used in folk medicine for their antidiabetic, diuretic, anticancer and blood pressure lowering properties. Crude extracts of this plant have been found to be cytotoxic to human cancer cell lines and protective against chemically-induced hepatocarcinogenesis in rats. In this study, the cytotoxicity of various sub-fractions of dichloromethane extract isolated from the leaves of <it>S. crispus </it>was determined and the anticancer activity of one of the bioactive sub-fractions, SC/D-F9, was further analysed in breast and prostate cancer cell lines.</p> <p>Methods</p> <p>The dichloromethane extract of <it>S. crispus </it>was chromatographed on silica gel by flash column chromatography. The ability of the various sub-fractions obtained to induce cell death of MCF-7, MDA-MB-231, PC-3 and DU-145 cell lines was determined using the LDH assay. The dose-response effect and the EC<sub>50 </sub>values of the active sub-fraction, SC/D-F9, were determined. Apoptosis was detected using Annexin V antibody and propidium iodide staining and analysed by fluorescence microscopy and flow cytometry, while caspase 3/7 activity was detected using FLICA caspase inhibitor and analysed by fluorescence microscopy.</p> <p>Results</p> <p>Selected sub-fractions of the dichloromethane extract induced death of MCF-7, MDA-MB-231, PC-3 and DU-145 cells. The sub-fraction SC/D-F9, consistently killed breast and prostate cancer cell lines with low EC<sub>50 </sub>values but is non-cytotoxic to the normal breast epithelial cell line, MCF-10A. SC/D-F9 displayed relatively higher cytotoxicity compared to tamoxifen, paclitaxel, docetaxel and doxorubicin. Cell death induced by SC/D-F9 occurred via apoptosis with the involvement of caspase 3 and/or 7.</p> <p>Conclusions</p> <p>A dichloromethane sub-fraction of <it>S. crispus </it>displayed potent anticancer activities <it>in vitro </it>that can be further exploited for the development of a potential therapeutic anticancer agent.</p

    Nonlinear dynamics of a spinning shaft with non-constant rotating speed

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    Research on spinning shafts is mostly restricted to cases of constant rotating speed without examining the dynamics during their spin-up or spin-down operation. In this article, initially the equations of motion for a spinning shaft with non-constant speed are derived, then the system is discretised, and finally a nonlinear dynamic analysis is performed using multiple scales perturbation method. The system in first-order approximation takes the form of two coupled sets of paired equations. The first pair describes the torsional and the rigid body rotation, whilst the second consists of the equations describing the two lateral bending motions. Notably, equations of the lateral bending motions of first-order approximation coincide with the system in case of constant rotating speed, and considering the amplitude modulation equations, as it is shown, there are detuning frequencies from the Campbell diagram. The nonlinear normal modes of the system have been determined analytically up to the second-order approximation. The comparison of the analytical solutions with direct numerical simulations shows good agreement up to the validity of the performed analysis. Finally, it is shown that the Campbell diagram in the case of spin-up or spin-down operation cannot describe the critical situations of the shaft. This work paves the way, for new safe operational ‘modes’ of rotating structures bypassing critical situations, and also it is essential to identify the validity of the tools for defining critical situations in rotating structures with non-constant rotating speeds, which can be applied not only in spinning shafts but in all rotating structures

    Signals in the Soil: An Introduction to Wireless Underground Communications

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    In this chapter, wireless underground (UG) communications are introduced. A detailed overview of WUC is given. A comprehensive review of research challenges in WUC is presented. The evolution of underground wireless is also discussed. Moreover, different component of UG communications is wireless. The WUC system architecture is explained with a detailed discussion of the anatomy of an underground mote. The examples of UG wireless communication systems are explored. Furthermore, the differences of UG wireless and over-the-air wireless are debated. Different types of wireless underground channel (e.g., In-Soil, Soil-to-Air, and Air-to-Soil) are reported as well

    Cross-sectional examination of 24-hour movement behaviours among 3-and 4-year-old children in urban and rural settings in low-income, middle-income and high-income countries : the SUNRISE study protocol

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    Introduction 24-hour movement behaviours (physical activity, sedentary behaviour and sleep) during the early years are associated with health and developmental outcomes, prompting the WHO to develop Global guidelines for physical activity, sedentary behaviour and sleep for children under 5 years of age. Prevalence data on 24-hour movement behaviours is lacking, particularly in low-income and middle-income countries (LMICs). This paper describes the development of the SUNRISE International Study of Movement Behaviours in the Early Years protocol, designed to address this gap. Methods and analysis SUNRISE is the first international cross-sectional study that aims to determine the proportion of 3- and 4-year-old children who meet the WHO Global guidelines. The study will assess if proportions differ by gender, urban/rural location and/or socioeconomic status. Executive function, motor skills and adiposity will be assessed and potential correlates of 24-hour movement behaviours examined. Pilot research from 24 countries (14 LMICs) informed the study design and protocol. Data are collected locally by research staff from partnering institutions who are trained throughout the research process. Piloting of all measures to determine protocol acceptability and feasibility was interrupted by COVID-19 but is nearing completion. At the time of publication 41 countries are participating in the SUNRISE study. Ethics and dissemination The SUNRISE protocol has received ethics approved from the University of Wollongong, Australia, and in each country by the applicable ethics committees. Approval is also sought from any relevant government departments or organisations. The results will inform global efforts to prevent childhood obesity and ensure young children reach their health and developmental potential. Findings on the correlates of movement behaviours can guide future interventions to improve the movement behaviours in culturally specific ways. Study findings will be disseminated via publications, conference presentations and may contribute to the development of local guidelines and public health interventions.Peer reviewe
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