96 research outputs found

    Studi Qsar Senyawa Turunan Triazolopiperazin Amida sebagai Inhibitor Enzim Dipeptidil Peptidase-IV (DPP IV) Menggunakan Metode Semiempirik AM1

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    Studi QSAR (Quatitative Structure-Activity Relationship) telah dilakukan untuk senyawa turunan triazolopiperazin amida sebagai inhibitor enzim DPP IV (dipeptidil peptidase-IV) yang merupakan penyebab diabetes melitus tipe 2. Studi ini dilakukan dengan pemodelan struktur senyawa turunan triazolopiperazin amida dan perhitungan deskriptor QSAR dilakukan dengan metode semiempirik AM 1 (Austin Model 1) yang tersedia dalam program Hyperchem®. Analisis QSAR dilakukan dengan metode analisis regresi multilinear untuk parameter elektronik dan molekular dengan program SPSS®. Model persamaan terbaik yang diperoleh dengan metode ini sebagai berikut.-log IC50 = 155,259 + (13,149*qC1) + (1692,869*qC9) + (1300,431*qC10) + (601,809*qO25) + (4,762*EH)n = 18; r2 = 0,566; adjusted r2 = 0,385; Fhit/Ftab = 1,007; PRESS = 5,500x10–

    Aplikasi Principal Component Regresion Untuk Analisis Qsar Senyawa Antioksidan Turunan Flavon/ Flavonol Menggunakan Deskriptor Elektronik Hasil Perhitungan Metode Am1

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    Telah dilakukan aplikasi teknik Principal Component Regresion (PCR) untuk analisis hubungan kuantitatif antara struktur elektronik dan aktivitas (QSAR) antioksidan dari senyawa turunan flavon / flavonol. Data aktivitas merupakan data sekunder yang diperoleh dari literatur dan masing-masing dinyatakan sebagai % aktivitas. Representasi struktur kimia berupa deskriptor elektronik meliputi muatan bersih atom dan momen dipol yang diperoleh dari hasil perhitungan metode semiempirik AM1. Evaluasi QSAR yang dilakuakan berupa analisis tahapan Principal Component Analysis (PCA) untuk mengkonversi variabel laten yang dilanjutkan dengan analisis regresi multilinier antara aktivitas dan variabel laten. Hasil penelitian ditunjukkan dengan model persamaan QSAR terpilih dengan menggunakan 4 komponen utama yang dipresentasikan dalam persamaan :%A = 212.2 + (7.196) T1-(20.593)T2-(192.906)T3+(242.706)T4; n=18; 2=0.822 Fhitung/Ftabel=1,397. Kata Kunci: QSAR, Principal Component Analysis, molecular modelin

    Pilarisasi dan Karakterisasi Montmorillonit

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    PILARISASI DAN KARAKTERISASI MONTMORILLONIT. Telah dilakukan pilarisasi montmorillonit dengan Cr2O3 dengan metode interkalasi dan karakterisasinya baik secara kualitatif maupun kuantitatif. Sintesis lempung terpilar dilakukan melalui dua tahap yaitu tahap pembuatan agent pemilar berupa oligomer kation chrom dan pemilaran montmorillonit. Pembuatan oligomer dilakukan dengan melarutkan garam Cr(NO3)3. 9H2O dalam air terdemineralisasi selama 36 jam dengan pemanasan pada suhu 95oC sambil diaduk dengan pengaduk magnet. Pemilaran lempung dilakukan dengan melarutkan Na-montmorillonit ke dalam larutan campuran air terdemineralisasi dan aseton, selanjutnya mencampurkan suspensi tersebut ke dalam larutan oligomer sambil diaduk dengan pengaduk magnet pada suhu pemanasan 40 oC selama 24 jam. Campuran disaring kemudian padatan yang diperoleh dikeringkan dan selanjutnya dikarakteristik menggunakan spektrofotometer inframerah, difraksi sinar-X, analisis adsorpsi gas dan analisis pengaktifan neutron. Analisis yang sama juga dilakukan pada Na-montmorillonit yang digunakan sebagai pembanding. Tahap selanjutnya adalah uji keasaman permukaan yang dilakukan secara kualitatif yaitu dengan metode spektrofotometer infra merah dan secara kuantitatif dengan metode gravimetri yaitu dengan mengadsorbsikan amoniak ke dalam montmorillonit terpilar Cr2O3. Hasil penelitian menunjukkan bahwa pilarisasi Na-montmorillonit dengan Cr2O3 membentuk montmorillonit terpilar Cr2O3 dengan tinggi pilar sebesar 5,95Ă…, Pilarisasi juga mengakibatkan kenaikan luas permukaan spesifik dari dari 90,0587 m2/g (Na-montmorillonit) menjadi 170,471 m2/g (montmorillonit terpilar) dan volume total pori dari 60,9264 x 10-3 cm3/g (Na-montmorillonit) menjadi 92,6631 x 10-3 cm3/g (montmorillonit terpilar Cr2O3). Keasaman permukaan montmorillonit meningkat dari 0,6673 mmol/g (Na-Montmorillonit) menjadi 2,6965 mmol/g (montmorillonit terpilar Cr2O3)

    Development and Evaluation of an Interactive Instructional Package for Teaching Engineering Graphics Skills

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    Exposure to modern pedagogical approaches and methods with appropriate instructional media can enhance the development of high-level critical thinking and technical skills. This study examined the development of an interactive instructional software package for teaching engineering graphics and evaluated its relative effectiveness on second-year undergraduate engineering students' academic achievement, skill transfer, and retention. In this study, the quasi-experimental, pre-test, post-test, control group design was employed. 45 research participants were sampled, employing two-stage stratified sampling technique, which comprises the simple random sampling to assign students into three groups from the study population and systematic sampling with k = 3 to select 15 students from each group to a control group and experimental groups A and B. The control group was exposed to conventional classroom instruction (CI), group A to computer-aided instruction (CAI); and group B to conventional and computer-aided instructions (CCAIs). A computer-aided learning package on engineering graphics was developed using the Camtasia software package, which served as the treatment instrument. The pre-test and post-test data used for analysis stemmed from a validated Engineering Graphics Achievement Test instrument. Analysis of covariance and Sidak post hoc test statistical analysis of the groups' performance provided the results on the comparative effects of the treatment conditions. Findings indicated significant differences between the academic achievement, skill transfer, and retention of students, exposed to CCAIs, and CI or CAI strategies. When used together, a significant improvement in students' academic achievement, transfer, and retention of engineering graphics skills occurred than either the CI or CAI strategy used alone

    Elucidating the structure, and composition of bacterial symbionts in the gut regions of wood-feeding termite, Coptotermes formosanus and their functional profile towards lignocellulolytic systems

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    The wood-feeding termite, Coptotermes formosanus, presents an efficient lignocellulolytic system, offering a distinctive model for the exploration of host-microbial symbiosis towards lignocellulose degradation. Despite decades of investigation, understanding the diversity, community structure, and functional profiles of bacterial symbionts within specific gut regions, particularly the foregut and midgut of C. formosanus, remains largely elusive. In light of this knowledge gap, our efforts focused on elucidating the diversity, community composition and functions of symbiotic bacteria inhabiting the foregut, midgut, and hindgut of C. formosanus via metagenomics. The termite harbored a diverse community of bacterial symbionts encompassing 352 genera and 26 known phyla, exhibiting an uneven distribution across gut regions. Notably, the hindgut displayed a higher relative abundance of phyla such as Bacteroidetes (56.9%) and Spirochetes (23.3%). In contrast, the foregut and midgut were predominantly occupied by Proteobacteria (28.9%) and Firmicutes (21.2%) after Bacteroidetes. The foregut harbored unique phyla like Candidate phylum_TM6 and Armatimonadetes. At the family level, Porphyromonadaceae (28.1, 40.6, and 53.5% abundance in foregut, midgut, and hindgut, respectively) and Spirochaetaceae (foregut = 9%, midgut = 16%, hindgut = 21.6%) emerged as dominant families in the termite’s gut regions. Enriched operational taxonomic units (OTUs) were most abundant in the foregut (28), followed by the hindgut (14), while the midgut exhibited enrichment of only two OTUs. Furthermore, the functional analyses revealed distinct influences of bacterial symbionts on various metabolic pathways, particularly carbohydrate and energy metabolisms of the host. Overall, these results underscore significant variations in the structure of the bacterial community among different gut regions of C. formosanus, suggesting unique functional roles of specific bacteria, thereby inspiring further investigations to resolve the crosstalk between host and microbiomes in individual gut-regions of the termite

    Implementation of ANN Controller Based UPQC Integrated with Microgrid

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    This study discusses how to increase power quality by integrating a unified power quality conditioner (UPQC) with a grid-connected microgrid for clean and efficient power generation. An Artificial Neural Network (ANN) controller for a voltage source converter-based UPQC is proposed to minimize the system’s cost and complexity by eliminating mathematical operations such as a-b-c to d-q-0 translation and the need for costly controllers such as DSPs and FPGAs. In this study, nonlinear unbalanced loads and harmonic supply voltage are used to assess the performance of PV-battery-UPQC using an ANN-based controller. Problems with voltage, such as sag and swell, are also considered. This work uses an ANN control system trained with the Levenberg-Marquardt backpropagation technique to provide effective reference signals and maintain the required dc-link capacitor voltage. In MATLAB/Simulink software, simulations of PV-battery-UPQC employing SRF-based control and ANN-control approaches are performed. The findings revealed that the proposed approach performed better, as presented in this paper. Furthermore, the influence of synchronous reference frame (SRF) and ANN controller-based UPQC on supply currents and the dc-link capacitor voltage response is studied. To demonstrate the superiority of the suggested controller, a comparison of percent THD in load voltage and supply current utilizing SRF-based control and ANN control methods is shown

    Carotid Artery Stenting and Its Impact on Cognitive Function: A Prospective Observational Study

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    Purpose Carotid artery stenting (CAS) has evolved as a first-line therapeutic option for carotid revascularization in indicated patients for stroke prevention, but there is still a lack of data on its effect on cognitive function (CF), especially among Indian patients. To determine the effect of CAS on CF and to study the immediate and delayed complications of CAS in Indian patients. Materials and Methods This was a prospective, observational, single-center study. CF was assessed using Addenbrooke’s cognitive examination version III (ACE) before and 3 months after stenting. The demographic and clinical parameters were also assessed. A follow-up evaluation after 3 months was done to compare CF and to observe the occurrence of any complications. Results Out of 31 patients, 3 were lost to follow up. There were no immediate or delayed procedure-related complications. There was a statistically significant improvement in overall ACE score and memory before and after stenting. On subgroup analysis of those with and without strokes, there was a significant improvement in visuospatial function and mean ACE score. Those with left CAS had significant improvement in memory, visuospatial, language, and ACE scores than right CAS. Conclusion CAS was associated with significant improvement in CF in patients

    Comparative evaluation of procoagulant and proinflammatory markers in drug naive versus oral contraceptive pill’s (OCP’s) treated Polycystic Ovary Syndrome (PCOS) women.

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    Polycystic ovary syndrome (PCOS) is the most common endocrine disorder of young women. There is a spectacular increase in the prevalence of PCOS all over world especially in Asia. The condition seems to be on rise in Kashmir valley although systemic studies on the subject are underway. First line of treatment is often the oral contraceptive pills (OCP’s) as most of these women attend to various gynaecologists and they desire menstrual regulation. Since there is plethora of data that PCOS women have evidence of enhanced markers of inflammation and indicators of coagulation. Therefore treatment with OCP’s may worsen the metabolic, inflammatory and coagulation parameters in this population. We undertook this study to investigate the effect of OCP treatment procoagulant and proinflammatory markers in women with PCOS. The results may therefore translate in to the clinical practice
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