3,671 research outputs found
Fire risk assessment of low cost high rise residential buildings in Kuala Lumpur: A case study
Low cost high rise residential buildings have had the highest number of fire incidents compared to other types of buildings in Malaysia. This study aims to determine the fire risk status of low cost high rise residential buildings in Kuala Lumpur through a fire risk assessment (FRA) approach. The study forms the exploratory pliase of a wider research to develop a fire risk indexing (FRI) methodology for low cost high rise residential buildings in Kuala Lumpur. On-site fire audits were performed on three (3) selected low cost high rise residential buildings in the Pantai area of Kuala Lumpur using a 10-item FRA checklist. The results showed that all 10 FRA criteria recorded multiple issues ranging from the presence of multiple ignition and fuel sources to inadequate or vandalized firefighting equipment to lack of training of occupants on fire risk and safety. Further analysis showed that the fire risk status of the observed buildings was ‘high’ A need for immediate intervention measures to improve the fire safety credentials of the observed case study buildings wras established. Recommendations include reconsidering the design layout of rooms, improving active and passive fire safety protection systems, and training of occupants to improve their awareness on fire safety. © 2017, University of Malaya. All rights reserved
Ultra-strong Adhesion of Graphene Membranes
As mechanical structures enter the nanoscale regime, the influence of van der
Waals forces increases. Graphene is attractive for nanomechanical systems
because its Young's modulus and strength are both intrinsically high, but the
mechanical behavior of graphene is also strongly influenced by the van der
Waals force. For example, this force clamps graphene samples to substrates, and
also holds together the individual graphene sheets in multilayer samples. Here
we use a pressurized blister test to directly measure the adhesion energy of
graphene sheets with a silicon oxide substrate. We find an adhesion energy of
0.45 \pm 0.02 J/m2 for monolayer graphene and 0.31 \pm 0.03 J/m2 for samples
containing 2-5 graphene sheets. These values are larger than the adhesion
energies measured in typical micromechanical structures and are comparable to
solid/liquid adhesion energies. We attribute this to the extreme flexibility of
graphene, which allows it to conform to the topography of even the smoothest
substrates, thus making its interaction with the substrate more liquid-like
than solid-like.Comment: to appear in Nature Nanotechnolog
Sub-Shot-Noise Quantum Optical Interferometry: A Comparison of Entangled State Performance within a Unified Measurement Scheme
Phase measurement using a lossless Mach-Zehnder interferometer with certain
entangled -photon states can lead to a phase sensitivity of the order of
1/N, the Heisenberg limit. However, previously considered output measurement
schemes are different for different input states to achieve this limit. We show
that it is possible to achieve this limit just by the parity measurement for
all the commonly proposed entangled states. Based on the parity measurement
scheme, the reductions of the phase sensitivity in the presence of photon loss
are examined for the various input states.Comment: 5 pages, 2 figure
Refractory topiramate-induced angle-closure glaucoma in a man: a case report
<p>Abstract</p> <p>Introduction</p> <p>Topiramate is a sulphonamide derivative indicated in the treatment of epilepsy and migraine. A known adverse affect is an idiosyncratic reaction that results in angle-closure glaucoma. We describe a patient with bilateral glaucoma related to topiramate that showed some unusual clinical features.</p> <p>Case presentation</p> <p>A 39-year-old Caucasian man presented with acute angle-closure glaucoma; he initially presented with intractable headaches after being treated with an escalating dose of topiramate. Clinical signs included elevated intraocular pressure that was initially refractory to treatment, shallow anterior chambers, and extensive bilateral choroidal effusions. After treatment with intravenous methylprednisolone, in conjunction with conventional glaucoma treatment, there was rapid reduction of intraocular pressure, gradual delayed resolution of the choroidal effusion and induced myopic shift; and eventually a good outcome without optic nerve damage.</p> <p>Conclusion</p> <p>This case illustrates the importance of recognizing this entity in a non-ophthalmic setting and that intravenous methylprednisolone may be useful in the treatment of the condition when it is not responsive to conventional treatment. In addition, it is important to recognize that complete resolution of visual symptoms from the myopic shift may be delayed, despite normalization of intraocular pressure.</p
Sorting live stem cells based on Sox2 mRNA expression.
PMCID: PMC3507951This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.While cell sorting usually relies on cell-surface protein markers, molecular beacons (MBs) offer the potential to sort cells based on the presence of any expressed mRNA and in principle could be extremely useful to sort rare cell populations from primary isolates. We show here how stem cells can be purified from mixed cell populations by sorting based on MBs. Specifically, we designed molecular beacons targeting Sox2, a well-known stem cell marker for murine embryonic (mES) and neural stem cells (NSC). One of our designed molecular beacons displayed an increase in fluorescence compared to a nonspecific molecular beacon both in vitro and in vivo when tested in mES and NSCs. We sorted Sox2-MB(+)SSEA1(+) cells from a mixed population of 4-day retinoic acid-treated mES cells and effectively isolated live undifferentiated stem cells. Additionally, Sox2-MB(+) cells isolated from primary mouse brains were sorted and generated neurospheres with higher efficiency than Sox2-MB(-) cells. These results demonstrate the utility of MBs for stem cell sorting in an mRNA-specific manner
Case study in six sigma methadology : manufacturing quality improvement and guidence for managers
This article discusses the successful implementation of Six Sigma methodology in a high precision and critical process in the manufacture of automotive products. The Six Sigma define–measure–analyse–improve–control approach resulted in a reduction of tolerance-related problems and improved the first pass yield from 85% to 99.4%. Data were collected on all possible causes and regression analysis, hypothesis testing, Taguchi methods, classification and regression tree, etc. were used to analyse the data and draw conclusions. Implementation of Six Sigma methodology had a significant financial impact on the profitability of the company. An approximate saving of US$70,000 per annum was reported, which is in addition to the customer-facing benefits of improved quality on returns and sales. The project also had the benefit of allowing the company to learn useful messages that will guide future Six Sigma activities
Micro-Electro-Mechanical-Systems (MEMS) and Fluid Flows
The micromachining technology that emerged in the late 1980s can provide micron-sized sensors and actuators. These micro transducers are able to be integrated with signal conditioning and processing circuitry to form micro-electro-mechanical-systems (MEMS) that can perform real-time distributed control. This capability opens up a new territory for flow control research. On the other hand, surface effects dominate the fluid flowing through these miniature mechanical devices because of the large surface-to-volume ratio in micron-scale configurations. We need to reexamine the surface forces in the momentum equation. Owing to their smallness, gas flows experience large Knudsen numbers, and therefore boundary conditions need to be modified. Besides being an enabling technology, MEMS also provide many challenges for fundamental flow-science research
Specialist role coaching and skill training periodisation: A football goalkeeping case study
© The Author(s) 2020. In sports like association football, professional teams are increasingly devoting resources to the role-based development of individual athletes and sub-groups. By employing ‘specialist coaches’ into athlete-support structures, clubs aim to facilitate individualised athlete training programs to enhance performance preparation as well as skill learning and talent development. Here, we discuss how contemporary pedagogical training approaches, like Nonlinear Pedagogy and the Constraints-Led approach, can enhance effectiveness of specialist role-based athlete development programs to facilitate performance functionality. We argue the need for a model of specialist role-based coaching practice in high performance sports organisations, based on a unified theoretical rationale, such as ecological dynamics. To exemplify the nature of specialist role-based coaching, a case study addresses how Nonlinear Pedagogy and Constraints-Led approach are being used for training professional football goalkeepers in an U23 years age group. Integrating key concepts from ecological dynamics, allied to principles of Nonlinear Pedagogy and the Constraints-Led approach, common skill training principles for specialist role coaches are highlighted. These illustrate the use of the recently introduced ‘Periodization of Skill Training’ framework for specialist role coaching, practically exemplifying a way to harness opportunities for performance enhancement and individualised talent development in the football goalkeeping context
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