35,531 research outputs found
FDM preparation of bio-compatible UHMWPE polymer for artificial implant
Due to its properties of high wear, creep resistance, high stiffness and strength, Ultra-High Molecular Weight Polyethylene (UHMWPE) was developed to eliminate most metallic wear in artificial implant, which conventionally found in stainless steel, Cobalt Chromium (Co-Cr) and Titanium (Ti) alloys. UHMWPE has an ultra-high viscosity that renders continuous melt-state processes including one of the additive manufacturing processes, Fused Deposition Modeling (FDM) ineffective for making UHMWPE implant. Attempt to overcome this problem and adapting this material to FDM is by blending UHMWPE with other polyethylene including High Density Polyethylene (HDPE) and Polyethylene-Glycol (PEG) which provide adequate mechanical properties for biomedical application along with the improvement in extrudability. It was demonstrated that the inclusion of 60% HDPE fraction has improved the flowability of UHMWPE in MFI test and showing adequate thermal stability in TGA
Nuclear Effects in Neutrino Induced Coherent Pion Production at K2K and MiniBooNE Neutrino Energies
The coherent pion production induced by neutrinos in nuclei is studied using
a delta hole model in local density approximation taking into account the
renormalization of properties in a nuclear medium. The pion absorption
effects have been included in an eikonal approximation. These effects give a
large reduction in the total cross section. The numerical results for the total
cross section are found to be consistent with recent experimental results from
K2K and MiniBooNE collaborations and other older experiments in the
intermediate energy region.Comment: 4pages, 5figure
Event by Event Analysis of High Multiplicity Events Produced in 158 A GeV/c 208 Pb- 208 Pb Collisions
An extensive analysis of individual high multiplicity events produced in 158
A GeV /c 208Pb- 208Pb collisions is carried by adopting different methods to
examine the anomalous behavior of these rare events. A method of selecting the
events with densely populated narrow regions or spikes out of a given sample of
collision events is discussed.Employing this approach two events with large
spikes in their eta- and phi- distributions are selected for further analysis.
For the sake of comparison, another two events which do not exhibit such spikes
are simultaneously analyzed. The findings suggest that the systematic studies
of particle density fluctuations in one- and two-dimensional phase-spaces and
comparison with those obtained from the studies of correlation free Monte Carlo
events, would be useful for identifying the events with large dynamical
fluctuations. Formation of clusters or jet like phenomena in multihadronic
final states in individual events is also discussed and the experimental
findings are compared with the independent particle emission hypothesis by
carrying out Monte Carlo simulations
CENP-C unwraps the human CENP-A nucleosome through the H2A C-terminal tail
Centromeres are defined epigenetically by nucleosomes containing the histone H3 variant CENP-A, upon which the constitutive centromere-associated network of proteins (CCAN) is built. CENP-C is considered to be a central organizer of the CCAN. We provide new molecular insights into the structure of human CENP-A nucleosomes, in isolation and in complex with the CENP-C central region (CENP-C-CR), the main CENP-A binding module of human CENP-C. We establish that the short alpha N helix of CENP-A promotes DNA flexibility at the nucleosome ends, independently of the sequence it wraps. Furthermore, we show that, in vitro, two regions of human CENP-C (CENP-C-CR and CENP-C-motif) both bind exclusively to the CENP-A nucleosome. We find CENP-C-CR to bind with high affinity due to an extended hydrophobic area made up of CENP-A(V)(532) and CENP-A(V)(533). Importantly, we identify two key conformational changes within the CENP-A nucleosome upon CENP-C binding. First, the loose DNA wrapping of CENP-A nucleosomes is further exacerbated, through destabilization of the H2A C-terminal tail. Second, CENP-C-CR rigidifies the N-terminal tail of H4 in the conformation favoring H4(K20) monomethylation, essential for a functional centromere
Default Risk On Islamic Banking In Indonesia
Stability of financial institutions is a crucial issue amid the economic crisis that hit the US and Europe. Islamic banking in Indonesia as financial institutions are also required to have good stability in order to maintain the stability of the national economy. The aim of this research is to determine the stability of Islamic banking in Indonesia, and understand the factors that affect the stability. Stability of Islamic banking will be measured using Merton model to estimate the Probability Default (PD). Panel data regression was used to estimate the factors that affect the stability of Islamic Banking. The object of this research is 10 Islamic banking in Indonesia that meet the specified criteria. From the analysis of the Merton model, the research found that the stability of Islamic banking in Indonesia is not good enough. This can be seen from the value of the probability default on Islamic banking which still above 0.5. However, based on the trend, the probability default of Islamic banking has decreased from year to year. Some of the variables that influence the stability of Islamic banking is asset and BI rate (SBI)
Kesan penggunaan koswer multimedia animasi visual terhadap pencapaian pelajar dalam mata pelajaran matematik
Ramai pelajar yang bermasalah dalam topik Pelan dan Dongakan. Ini kerana pelajar sukar untuk membayangkan objek yang tersembunyi melalui proses pengajaran dan pembelajaran (P&P) secara konvensional. Penyelidik telah membangunkan satu koswer multimedia animasi visual dalam topik Pelan dan Dongakan dengan menerapkan kesemua elemen-elemen yang dapat membantu meningkatkan kemahiran visual iaitu elemen animasi, video, audio, grafik dan teks. Seterusnya, kajian kuasi eksperimental ini turut dijalankan bertujuan untuk mengetahui kesan penggunaan koswer multimedia animasi visual terhadap pencapaian pelajar bagi mata pelajaran Matematik di sekolah menengah. Ujian Pra dan Ujian Pos digunakan untuk melihat perbezaan pencapaian yang signifikan selepas menggunakan koswer multimedia animasi visual yang menggunakan teori Kognitif Visual Wiley. Responden yang terlibat dalam kajian ini ialah seramai 40 orang pelajar Tingkatan Lima yang dibahagikan kepada dua kumpulan iaitu kumpulan rawatan dan kumpulan kawalan yang dipilih daripada sebuah sekolah di daerah Batu Pahat, Johor. Hasil analisis menunjukkan peningkatan skor min markah bagi pelajar kumpulan rawatan. Hasil analisis ujian-t (paired-sample-t-test) membuktikan bahawa wujudnya perbezaan skor min markah yang signifikan di antara markah ujian pra dan markah ujian pos bagi kumpulan rawatan. Oleh itu, terdapat perbezaan yang signifikan di antara skor min markah ujian pra dan ujian pos bagi pelajar kumpulan rawatan selepas menggunakan koswer multimedia animasi visual. Manakala instrumen soal selidik yang digunakan untuk melihat tahap penerimaan pelajar selepas menggunakan koswer multimedia animasi visual berdasarkan tiga aspek iaitu aspek isi kandungan, aspek interaksi dan aspek persembahan telah memeperolehi skor min yang tinggi bagi ketiga-tiga aspek tersebut. Dapatan kajian ini menggambarkan penggunaan koswer multimedia animasi visual dapat membantu meningkatkan pencapaian Matematik di dalam bilik darjah terutama yang tidak melibatkan pengiraan
Pool boiling on modified surfaces using R-123
This article has been made available through the Brunel Open Access Publishing Fund.Saturated pool boiling of R-123 was investigated for five horizontal copper surfaces modified by different treatments, namely, an emery-polished surface, a fine sandblasted surface, a rough sandblasted surface, an electron beam-enhanced surface, and a sintered surface. Each 40-mm-diameter heating surface formed the upper face of an oxygen-free copper block, electrically heated by embedded cartridge heaters. The experiments were performed from the natural convection regime through nucleate boiling up to the critical heat flux, with both increasing and decreasing heat flux, at 1.01 bar, and additionally at 2 bar and 4 bar for the emery-polished surface. Significant enhancement of heat transfer with increasing surface modification was demonstrated, particularly for the electron beam-enhanced and sintered surfaces. The emery-polished and sandblasted surface results are compared with nucleate boiling correlations and other published data. © 2014 Syed W. Ahmad, John S. Lewis, Ryan J. McGlen, and Tassos G. Karayiannis Published with license by Taylor & Francis
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