Studi Eksperimen Pengaruh Upstream Disturbance Body Terhadap Gaya Hambat Silinder Tunggal Dan Pressure Drop Saluran

Gaya drag dipengaruhi oleh beberapa hal yaitu intensitas turbulensi aliran, geometri suatu benda, kekasaran permukaan dan lain-lain. Intensitas turbulensi aliran yang melintasi benda dapat dipengaruhi pengganggu yang berada di depan permukaan benda tersebut. Penelitian ini bertujuan untuk mengetahui pengaruh silinder pengganggu terhadap gaya drag silinder tunggal dan juga pressure drop saluran. Penelitian ini dilakukan secara eksperimen pada sebuah wind tunnel berdimensi 200 mm x 200 mm x 1800 mm. Benda uji yang digunakan berupa silinder sirkular berdiameter (D) 25 mm yang disusun secara tandem terhadap Upstream Disturbance Bodi (UDB) berbentuk silinder sirkular. Diameter UDB (d) yaitu 4 mm dan 8 mm. Variasi jarak antar silinder L/D 1,25-3,00 dengan interval 0,25. Bilangan Reynolds (ReDh) yang digunakan dalam pengambilan data pressure drop 7,37x104 ; 8,04x104 ; 9,38x104 ; 1,07x105 ;1,2x105. Untuk pengambilan data koefisien tekanan dan perhitungan koefisien drag secara eksperimen digunakan ReDh 7,37x104 pada L/D 1,75 ; d/D 0,16, L/D 2,0 ; d/D 0,32 dan ReDh 1,07x105 pada L/D 1,25 untuk d/D 0,16 maupun 0,32. Hasil yang diperoleh menunjukkan nilai pressure drop susunan terendah yaitu 1,2 kali nilai pressure drop silinder tunggal terjadi pada variasi L/D 1,25 dan d/D 0,32. Pada susunan ini pula, koefisien drag tekanan silinder turun sebesar 42% dari koefisien drag tekanan silinder tunggal. ========== Drag force was influenced by turbulent intensity, bluff body’s geometry, and contour’s roughness. Disturbance body which is laid in front of main body can change the turbulent intensity. The objective of this present study was to investigate experimentally the influence of upstream disturbance body on the single cylinder’s drag force and on the duct’s pressure drop. Experiment was conducted in a wind tunnel with a test section of 200 mm width, 200 mm height, and 1800 m length. The Upstream Disturbance Body (UDB) was laid on the upstream of main circular cylinder (D = 25 mm). The diameter of Upstream Disturbance Body ranged from 4mm and 8mm. The spacing ratio of main cylinder to Upstream Disturbance Body (UDB) were varied from L/D 1,25-3,00 with interval of 0,25. Reynolds Number based on hydraulic diameter (ReDh ) for pressure drop’s experiment ranged from 7,37x104 ; 8,04x104 ; 9,38x104 ; 1,07x105 ;1,2x105. The drag coefficient of main circular cylinder decreased about 42% when a pair of 8 mm Upstream Disturbance Body (UDB) was installed at spacing ratio (L/D) 1,25. The maximum value of pressure drop from this variation was 1,2 times higher than pressure drop of single cylinder

Chemical constituents and antimicrobial activity of Goniothalamus macrophyllus (Annonaceae) from Pasoh Forest Reserve, Malaysia

The essential oils from the twig and root of Goniothalamus macrophyllus were obtained by hydrodistillation and subjected to Gas Chromatography (GC-FID) and Gas Chromatography/Mass Spectrometry (GC-MS) using CBP-5 capillary column in order to determine their chemical composition. Both twig and root oils and four reference standard compounds (-pinene, linalool, geraniol and geranyl acetate) were evaluated for their antimicrobial properties against gram positive and gram negative bacteria, yeast and dermatophyte fungi using broth microdilution methods. The GCMS analysis revealed twenty-one and fourteen compounds from twig and root oils which represented 90.0 and 42.5% of the total oils, respectively. The oils were found to possess the following major components: twig: geranyl acetate (45.5%), geraniol (17.0%), linalool (12.7%) and camphene (7.5%); root: cyperene (9.8%), geranyl acetate (9.4%), geraniol (3.4%) and linalool (2.6%). Other components present in appreciable amounts in both essential oils were -pinene (0.8%) and benzaldehyde (0.5%). The root oil exhibited the most notable inhibitory activity (0.3 mg/ml) against Vancomycin intermediate-resistance Staphylococcus aureus (VISA 24), Staphylococcus epidermidis and Candida albicans. -pinene meanwhile inhibited the bacteria and fungal growth at 0.3 and 2.5 mg/ml. With regards to antimicrobial potential, -pinene superceeds linalool, geraniol and geranyl acetate, respectively.Keywords: Goniothalamus macrophyllus, Annonaceae, essential oils, geranyl acetate, cyperene, geraniol, linalool, -pinene, antimicrobial activityAfrican Journal of Biotechnology Vol. 9(34), pp. 5511-5515, 23 August, 201

Christmas Disease (Hemophilia B) A Case Report

We report a 25 years old man developed Haemarthrosis of left hip joint with a history of recurrent swelling and pain in multiple joints and prolonged bleeding following minor trauma since childhood. Subsequent investigations revealed Christmas disease (Haemophilia B). Hemophilia B is an X-linked bleeding disorder. This case emphasises the importance of considering a diagnosis of haemophilia in a man with unexplained bleeding, even in the absence of a positive family history. DOI: 10.3329/bsmmuj.v2i2.4766 BSMMU J 2009; 2(2): 90-9

Relationship between weather variables and new daily covid-19 cases in Dhaka, Bangladesh

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The present study investigated the relationship between the transmission of COVID-19 infections and climate indicators in Dhaka, Bangladesh, using coronavirus infections data available from the Institute of Epidemiology, Disease Control and Research (IEDCR), Bangladesh. The Spearman rank correlation test was carried out to study the association of seven climate indicators, including humidity, air quality, minimum temperature, precipitation, maximum temperature, mean temperature, and wind speed with the COVID-19 outbreak in Dhaka, Bangladesh. The study found that, among the seven indicators, only two indicators (minimum temperature and average temperature) had a significant relationship with new COVID-19 cases. The study also found that air quality index (AQI) had a strong negative correlation with cumulative cases of COVID-19 in Dhaka city. The results of this paper will give health regulators and policymakers valuable information to lessen the COVID-19 spread in Dhaka and other countries around the world

Penghitungan Biaya Satuan (Unit Cost) Pendidikan Dengan Model Activity Based Costing (ABC) Pada Sekolah Menengah Kejuruan Di Daerah Istimewa Yogyakarta

Tujuan yang hendak dicapai dalam penelitian ini adalah: 1) Menemukan model penghitungan unit cost pendidikan di SMK dengan activity based costing 2) Menghasilkan perangkat penerapan model penghitungan unit cost pendidikan di SMK dengan activity based costing. Tujuan akhir dari penelitian ini adalah dihasilkannya besaran biaya satuan sesuai standar untuk mendukung tercapainya kualitas pendidikan di SMK. Penghitungan biaya satuan (unit cost) di SMK dilakukan dengan model activity based costing (ABC). ABC membantu mengurangi distorsi yang disebabkan oleh alokasi biaya tradisional. ABC menyajikan pengukuran yang lebih akurat tentang biaya yang dipicu oleh adanya aktivitas, hal ini dapat membantu manajemen untuk meningkatkan ‘product value’ dan process value. Penelitian termasuk R&D menggunakan four-d model Thiaragajan. Data dikumpulkan dengan metode wawancara, dokumentasi, FGD. Sampel responden adalah kepala sekolah, wakil kepala sekolah, bendahara sekolah, bendahara Dinas Pendidikan. Sampel Sekolah 9 SMKN di DIY. Penelitian ini berhasil mengembangkan dua model penghitungan unit cost dengan activity based costing (ABC) serta menghasilkan perangkat penerapan modelnya yaitu Template untuk menghitung unit cost di masingmasing Paket Keahlian di SMKN. Hasil penilaian dari pakar menunjukkan skor rata-rata aspek penilaian dua model dalam kategori sangat baik/layak untuk diterapkan di tahun ke dua, dianalisis dan ditetapkan salah satu model yang fisibel untuk diterapkan dalam skala luas di SMKN Daerah Istimewa Yogyakarta. Di tahun ketiga direncanakan akan dilanjutkan dengan pengembangan satu program aplikasi yang akan lebih mempermudah penerapan model penghitungan unit cost di SMK pada umumnya

Convergence of Humans, Bats, Trees, and Culture in Nipah Virus Transmission, Bangladesh.

Preventing emergence of new zoonotic viruses depends on understanding determinants for human risk. Nipah virus (NiV) is a lethal zoonotic pathogen that has spilled over from bats into human populations, with limited person-to-person transmission. We examined ecologic and human behavioral drivers of geographic variation for risk of NiV infection in Bangladesh. We visited 60 villages during 2011-2013 where cases of infection with NiV were identified and 147 control villages. We compared case villages with control villages for most likely drivers for risk of infection, including number of bats, persons, and date palm sap trees, and human date palm sap consumption behavior. Case villages were similar to control villages in many ways, including number of bats, persons, and date palm sap trees, but had a higher proportion of households in which someone drank sap. Reducing human consumption of sap could reduce virus transmission and risk for emergence of a more highly transmissible NiV strain

Antidiabetic effect of actinodaphne angustifolia and profiling of bioactive metabolites using UPLC-QToF/ESI-MS method

Diabetes mellitus is a chronic disorder that causes elevated blood glucose levels due to a lack of insulin, either completely or partially. We investigated the antidiabetic property of Actinodaphne angustifolia in a rat model and identified the bioactive phytochemicals by using the UPLC-QTOF/ESI-MS method. The rats’ pancreatic structures, lipid profile and blood glucose were assessed after a one-week intervention. UPLC-QTOF/ESI-MS analysis was conducted to identify flavonoids and terpenoids in the leaf extract. Actinodaphne angustifolia extract markedly increased the high-density lipoprotein (HDL) (p<0.05) while reducing total cholesterol (TC), low-density lipoprotein (LDL) and blood glucose. Furthermore, the tissue architecture of pancreatic islets was also well recovered as compared to the control group. A total of 45 flavonoids and 109 terpenoid compounds were identified using UPLC-QTOF/ESI-MS-based analysis and additional studies should be undertaken to identify the potential antidiabetic agents

RNA-Seq Analysis Reveals Different Dynamics of Differentiation of Human Dermis- and Adipose-Derived Stromal Stem Cells

Tissue regeneration and recovery in the adult body depends on self-renewal and differentiation of stem and progenitor cells. Mesenchymal stem cells (MSCs) that have the ability to differentiate into various cell types, have been isolated from the stromal fraction of virtually all tissues. However, little is known about the true identity of MSCs. MSC populations exhibit great tissue-, location- and patient-specific variation in gene expression and are heterogeneous in cell composition.Our aim was to analyze the dynamics of differentiation of two closely related stromal cell types, adipose tissue-derived MSCs (AdMSCs) and dermal fibroblasts (FBs) along adipogenic, osteogenic and chondrogenic lineages using multiplex RNA-seq technology. We found that undifferentiated donor-matched AdMSCs and FBs are distinct populations that stay different upon differentiation into adipocytes, osteoblasts and chondrocytes. The changes in lineage-specific gene expression occur early in differentiation and persist over time in both AdMSCs and FBs. Further, AdMSCs and FBs exhibit similar dynamics of adipogenic and osteogenic differentiation but different dynamics of chondrogenic differentiation.Our findings suggest that stromal stem cells including AdMSCs and dermal FBs exploit different molecular mechanisms of differentiation to reach a common cell fate. The early mechanisms of differentiation are lineage-specific and are similar for adipogenic and osteogenic differentiation but are distinct for chondrogenic differentiation between AdMSCs and FBs