3,471 research outputs found
Sensor material characterisation for magnetometer application
Pengukuran dan gangguan medan magnet arus terus dan arus ulang-alik memerlukan penderia medan magnet yang mempunyai kepekaan yang tinggi dan stabil. Untuk menghasilkan penderia tersebut, ciri-ciri bahan magnet yang baik telah dikenalpasti. Beberapa jenis bahan magnet yang berbeza telah digunakan untuk mengkaji ciri-ciri dan kesannya terhadap medan magnet. Teras gelang yang diperbuat daripada bahan-bahan magnet tersebut direkabentuk dengan dimensi yang sama bagi membolehkan perbandingan dibuat dengan mudah. Selain itu, rod tunggal dan berkembar juga telah digunakan sebagai teras penderia fluxgate, untuk melihat prestasi setiap jenis penderia tersebut. Kedua-dua penderia tersebut telah diuji dengan menggunakan dua sumber bahan magnet iaitu bar magnet tetap dan solenoid dengan diameter dawai yang berbeza. Isyarat keluaran bagi setiap penderia fluxgate seterusnya diproses bagi mengenalpasti hubungannya dengan ketumpatan medan magnet
Single side damage simulations and detection in beam-like structures
Beam-like structures are the most common components in real engineering, while single side damage is often encountered. In this study, a numerical analysis of single side damage in a free-free beam is analysed with three different finite element models; namely solid, shell and beam models for demonstrating their performance in simulating real structures. Similar to experiment, damage is introduced into one side of the beam, and natural frequencies are extracted from the simulations and compared with experimental and analytical results. Mode shapes are also analysed with modal assurance criterion. The results from simulations reveal a good performance of the three models in extracting natural frequencies, and solid model performs better than shell while shell model performs better than beam model under intact state. For damaged states, the natural frequencies captured from solid model show more sensitivity to damage severity than shell model and shell model performs similar to the beam model in distinguishing damage. The main contribution of this paper is to perform a comparison between three finite element models and experimental data as well as analytical solutions. The finite element results show a relatively well performanc
Penghasilan modul pembelajaran lukisan kejuruteraan berbantukan komputer
Perkembangan teknologi maklumat dalam dunia pendidikan tidak lagi boleh dinafikan pada masa kini. Keperluan yang meningkat dalam sistem pembelajaran dan pengajaran memerlukan mereka yang terlibat memberi sepenuh tumpuan terhadap mata pelajaran bagi mencapai matlamat. Untuk tujuan ini Modul Pembelajaran Lukisan Kejuruteraan berbantukan Komputer dihasilkan bagi membantu memudahkan pelajar dalam mata pelajaran Lukisan kejuruteraan. Statistik deskriptif digunakan dalam mengumpul dan menganalisis data. Secara keseluruhannya dari hasil kajian, menunjukkan para pelajar memberikan maklum balas yang positif terhadap modul ini. Semua responden memberi tindak balas positif terhadap modul dari segi mesra pengguna, isi kandungan, motivasi dan daya kognitif. Hasil dari kajian ini, didapati bahawa kebanyakan pelajar berminat terhadap Modul Pembelajaran Lukisan Kejuruteraan Berbantukan Komputer. Walau bagaimanapun masih terdapat beberapa aspek yang perlu diperbaiki untuk memantapkan modul ini
Kajian Karakteristik Bangunan Ikonik pada Gedung Puspa Iptek Kota Baru Parahyangan
Perkembangan dunia arsitektur kian pesat ditandai dengan banyak bermunculan bangunan-bangunan arsitektur ikonik di berbagai kota besar dunia. Arsitektur Ikonik merupakan karya arsitektur yang dapat dijadikan sebagai tanda tempat di lingkungan sekitar ataupun karya arsitektur yang menjadi tanda dari era waktu tertentu. Penelitian ini diawali dengan mengkaji bangunan-bangunan ikonik untuk mendapatkan karakteristik umum arsitektur ikonik. karakteristik umum yang didapatkan. Selanjurnya dijadikan dasar dalam melakukan kajian arsitektur ikonik. Bangunan utama yang dikaji adalah bangunan Puspa IPTEK di Kota Baru Parahyangan yang merupakan bangunan jam matahari pertama dan terbesar di Indonesia dan berfungsi sebagai museum ilmu pengetahuan dan teknologi. Teknis pengumpulan data yang digunakan dalam penelitian adalah mengumpulkan data berupa studi literatur, survey lapangan dan wawancara. Dari hasil studi didapatkan bahwa sebuah bangunan disebut sebagai bangunan ikon apabila bangunan tersebut merupakan sesuatu yang baru pada zamannya, berbentuk atraktif, simetris, memiliki proporsi dan skala yang sempurna, ritme pada facade dan membentuk vista secara visual sehingga bangunan Puspa IPTEK Kota Baru Parahyangan dinilai memiliki kriteria sebagai bangunan ikonik dan ikon kawasan Kota Baru Parahyanga
TGF-beta 1 induces human alveolar epithelial to mesenchymal cell transition (EMT)
Background: Fibroblastic foci are characteristic features in lung parenchyma of patients with idiopathic pulmonary fibrosis (IPF). They comprise aggregates of mesenchymal cells which underlie sites of unresolved epithelial injury and are associated with progression of fibrosis. However, the cellular origins of these mesenchymal phenotypes remain unclear. We examined whether the potent fibrogenic cytokine TGF-β1 could induce epithelial mesenchymal transition (EMT) in the human alveolar epithelial cell line, A549, and investigated the signaling pathway of TGF-β1-mediated EMT.
Methods: A549 cells were examined for evidence of EMT after treatment with TGF-β1. EMT was assessed by: morphology under phase-contrast microscopy; Western analysis of cell lysates for expression of mesenchymal phenotypic markers including fibronectin EDA (Fn-EDA), and expression of epithelial phenotypic markers including E-cadherin (E-cad). Markers of fibrogenesis, including collagens and connective tissue growth factor (CTGF) were also evaluated by measuring mRNA level using RT-PCR, and protein by immunofluorescence or Western blotting. Signaling pathways for EMT were characterized by Western analysis of cell lysates using monoclonal antibodies to detect phosphorylated Erk1/2 and Smad2 after TGF-β1 treatment in the presence or absence of MEK inhibitors. The role of Smad2 in TGF-β1-mediated EMT was investigated using siRNA.
Results: The data showed that TGF-β1, but not TNF-α or IL-1β, induced A549 cells with an alveolar epithelial type II cell phenotype to undergo EMT in a time-and concentration-dependent manner. The process of EMT was accompanied by morphological alteration and expression of the fibroblast phenotypic markers Fn-EDA and vimentin, concomitant with a downregulation of the epithelial phenotype marker E-cad. Furthermore, cells that had undergone EMT showed enhanced expression of markers of fibrogenesis including collagens type I and III and CTGF. MMP-2 expression was also evidenced. TGF-β1-induced EMT occurred through phosphorylation of Smad2 and was inhibited by Smad2 gene silencing; MEK inhibitors failed to attenuate either EMT-associated Smad2 phosphorylation or the observed phenotypic changes.
Conclusion: Our study shows that TGF-β1 induces A549 alveolar epithelial cells to undergo EMT via Smad2 activation. Our data support the concept of EMT in lung epithelial cells, and suggest the need for further studies to investigate the phenomenon
Evaluation of trichoderma isolates as potential biological control agent against soybean charcoal rot disease caused by Macrophomina phaseolina
Macrophomina phaseolina (Tassi) Goid remains the prevailing causal agent of charcoal rot disease that significantly suppresses the yield of a variety of oilseed crops. Its wide host range and ability to survive under arid conditions, coupled with the ineffective use of fungicides against it, have spurred scientific endeavours for alternative avenues to control this phytopathogen. Hence, the present study aimed to provide empirical evidence of the efficacy of three fungal isolates (T2, T10 and T12) of Trichoderma harzianum as biological control agents against charcoal rot in soybean (Glycine max L.). The results of the in vitro studies revealed that all three fungal isolates significantly inhibited the growth of M. phaseolina phytopathogen, with T12 showing considerably higher inhibition effect than T2 and T10 isolates. T12 inhibited the growth of M. phaseolina in the dual culture (72.31%) and volatile production (63.36%) assays, and the hyperparasitism test indicated cell lysis following the interactions with T12 mycelia. T12 isolate was mostly effective in field experiments, observable in the attained minimum plant disease indices both in the soil incorporation (11.98%) and seed inoculation (5.55%) treatments, in comparison to isolates T2 and T10. Moreover, the stem and root lengths, as well as the seed weight, were considerably increased, as compared to the control. Hence, the findings reported in the present study supported the applicability of T12 isolate as possible alternative to fungicides for the control of charcoal rot in soybean
Impact of different water levels on growth, plant water relations and leaf characteristics in seedling of Tongkat Ali (Eurycoma longifolia Jack)
The effects of water availability on growth, water relations and related plant leaves characteristics of young Tongkat Ali (Eurycoma longifolia jack) plants were investigated. Plant vegetative growth was inhibited with reduced water availability. Leaf water potential and relative water content were reduced with increasing soil water stress. The total leaf area and specific leaf area (SLA) in Tongkat Ali decreased in response to the stress treatments especially from moderate stress (75%FC), to severe stress (25% FC), compared with the control. Therefore by decreasing the SLA plant can preserve the internal water led to increase the tolerance of plant in case of water deficit condition
The potential use of service-oriented infrastructure framework to enable transparent vertical scalability of cloud computing infrastructure
Cloud computing technology has become familiar to most Internet users. Subsequently, there has been an increased growth in the use of cloud computing, including Infrastructure as a Service (IaaS). To ensure that IaaS can easily meet the growing demand, IaaS providers usually increase the capacity of their facilities in a vertical IaaS increase capability and the capacity for local IaaS amenities such as increasing the number of servers, storage and network bandwidth. However, at the same time, horizontal scalability is sometimes not enough and requires additional strategies to ensure that the large number of IaaS service requests can be met. Therefore, strategies requiring horizontal scalability are more complex than the vertical scalability strategies because they involve the interaction of more than one facility at different service centers. To reduce the complexity of the implementation of the horizontal scalability of the IaaS infrastructures, the use of a technology service oriented infrastructure is recommended to ensure that the interaction between two or more different service centers can be done more simply and easily even though it is likely to involve a wide range of communication technologies and different cloud computing management. This is because the service oriented infrastructure acts as a middle man that translates and processes interactions and protocols of different cloud computing infrastructures without the modification of the complex to ensure horizontal scalability can be run easily and smoothly. This paper presents the potential of using a service-oriented infrastructure framework to enable transparent vertical scalability of cloud computing infrastructures by adapting three projects in this research: SLA@SOI consortium, Open Cloud Computing Interface (OCCI), and OpenStack
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