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Low-cost accelerograph units as earthquake alert devices for Mexico City: how well would they work?
García, D.;Singh, S. K.;Iglesias, A.;Quintanar, L.;Valdés, C.;
Geofísica internacional , 2009,
Abstract: recently, low-cost accelerograph units have been proposed as earthquake alert devices for mexico city. these units would trigger when the acceleration reaches a pre-established level, presumably 4 gal. for significant earthquakes, this would occur during p wave or in the early part of its coda. we test the performance of such a unit on accelerograms recorded in the period 1985 - 2008 at sct and cdao, two lake-bed sites in mexico city. as expected, the alert time (the time of arrival of intense ground motion minus the trigger time), ta, for regional earthquakes is found to increase with the pga. ta of the recorded accelerograms (with pga > 4 gal) ranges between about -20 and 45 sec; the largest values of ta correspond to the 1985 michoacan earthquake. with some exceptions, ta is greater than 15 sec for earthquakes which produced pga > 20 gal. the device may be useful in mitigating injuries and loss of lives if an alert time of 15 to 45 sec is sufficient to put in to effect pre-established safety measures. this may be practical for one- to three-storey public school buildings. the device would be useful for shutting critical facilities before the arrival of large-amplitude ground motion.
Low-cost accelerograph units as earthquake alert devices for Mexico City: how well would they work?  [PDF]
D. García,S. K. Singh,A. Iglesias,L. Quintanar
Geofísica internacional , 2009,
Abstract: Recently, low-cost accelerograph units have been proposed as earthquake alert devices for Mexico City. These units would trigger when the acceleration reaches a pre-established level, presumably 4 gal. For significant earthquakes, this would occur during P wave or in the early part of its coda. We test the performance of such a unit on accelerograms recorded in the period 1985 - 2008 at SCT and CDAO, two lake-bed sites in Mexico City. As expected, the alert time (the time of arrival of intense ground motion minus the trigger time), TA, for regional earthquakes is found to increase with the PGA. TA of the recorded accelerograms (with PGA > 4 gal) ranges between about -20 and 45 sec; the largest values of TA correspond to the 1985 Michoacan earthquake. With some exceptions, TA is greater than ~15 sec for earthquakes which produced PGA > 20 gal. The device may be useful in mitigating injuries and loss of lives if an alert time of 15 to 45 sec is sufficient to put in to effect pre-established safety measures. This may be practical for one- to three-storey public school buildings. The device would be useful for shutting critical facilities before the arrival of large- amplitude ground motion.
Evaluation of Brazilian medical devices using agar diffusion cytotoxicity assay
Vidal, Mirian N. P.;Aiub, Claudia;Abrantes, Shirley;Zamith, Helena P. S.;
Revista Brasileira de Hematologia e Hemoterapia , 2009, DOI: 10.1590/S1516-84842009000200009
Abstract: over the last decades, governmental actions and mechanisms created to protect consumer rights have been linked to a growing effort to guarantee the quality and reliability of products. samples of condoms (latex), medical devices and blood bags (pvc - polyvinyl chloride) have been tested using the agar diffusion assay. this assay evaluates the cytotoxicity induced by biomaterials by measuring the biological reactivity of mammalian cell cultures in contact with these materials. pvc is used in the production of medical devices because of its specific properties, such as flexibility, obtained after the addition of plasticizers (phthalates), which can cause toxicity even at low doses. latex is a natural elastomer used for surgical gloves and condoms with a formulation that includes dispersion of liquid latex and chemicals, such as antioxidants and a vulcanizing accelerator, both of which are able to induce cytotoxicity. samples were analyzed by the national institute of quality control in health - incqs of the oswaldo cruz foundation (fiocruz) in accordance with the governmental sanitary surveillance actions on respect to the quality control. we observed an increase in the quality of the products in relation to the results of the agar diffusion assay during the period between 2000 and 2007. this situation, together with other actions, reflects in an improvement in the quality of products that can be translated in the health of the population.
Proposal of methodology and test protocol for evaluating and qualifying pH measuring devices
Almeida, Niza Helena de;Nohama, Percy;
Brazilian Archives of Biology and Technology , 2006, DOI: 10.1590/S1516-89132006000200005
Abstract: we present a proposal for evaluating and qualifying ph measuring devices based on the requirements of relevant standards. the proposal presented is based on astm e70, nbr 7353, jis z 8805, bs 3145, din 19268, nbr iso 17025 and other standards, as well as the results of field research carried out in conjunction with professionals performing ph measurements in public health laboratories. evaluation is performed by inspection of a form which records data from the measuring system. the form gives acceptable variations in the parameters being tested and allows a conclusion to be reached regarding acceptability of the system. using the proposed protocol allows definition of suitable analysis criteria, while taking into account the influence ph measurement is subject and the need for correct results. this is particularly true when analyzing products already on the market, thus underlining the protocol's importance to the public health area.
Microfluidics in biotechnology
Richard Barry, Dimitri Ivanov
Journal of Nanobiotechnology , 2004, DOI: 10.1186/1477-3155-2-2
Abstract: Current analytical techniques in biotechnology can potentially benefit from an integrated reduction in scale through lowered production and operating costs, and via the specific dynamics of flowing fluids occurring at the mico-scale, which enable the generation of accurate quantitative assays. Microfluidics combines multiple disciplines including biotechnology, microtechnology, physics, and analytical chemistry and has flourished as a research field. The processes involved in biotechnology and microfluidics technologies take place on a very small scale (microns to millimetres) where some physical processes can become enhanced, e.g. osmotic movement, electrophoretic motility and surface interactions. Microfluidics technology has essentially taken advantage of the inherent properties of liquids and gases at the microscale and combined this with semiconductor technology in order to build singular devices using a streamlined manufacturing process.In general, microfluidic devices can offer a number of advantages over more conventional systems, e.g. their compact size, disposable nature, increased utility and a prerequisite for reduced concentrations of sample reagents. Miniaturised assemblies can be designed to perform a wide range of tasks that range from detecting airborne toxins to analysing DNA and protein sequences. Therefore, microfluidics systems provide a real potential for improving the efficiency of techniques applied in drug discovery and diagnostics. In order for microfluidic technology to interface with, and provide improvements for, current assaying techniques it needs to be adaptable. Some commercial microfluidics systems illustrate their suitability to biotechnological applications.Typical devices include passive flow systems, such as the Passive Fluid Control (PFC?) micro fluid analysis system by BioMicro Systems http://www.biomicro.com webcite. PFC incorporates 'building block-like' components into circuit designs in order to carry out sample processing
Evaluating Cytotoxicity of Hyaluronate Targeted Solid Lipid Nanoparticles of Etoposide on SK-OV-3 Cells  [PDF]
Parviz Mohammadi Ghalaei,Jaleh Varshosaz,Hojatollah Sadeghi Aliabadi
Journal of Drug Delivery , 2014, DOI: 10.1155/2014/746325
Abstract: The epithelial ovarian carcinoma is one of the most fatal gynecological cancers. Etoposide is used in treating platinum-resistant ovarian cancer. Sodium hyaluronate is a substance that binds to the CD44 receptors overexpressed in SK-OV-3 cells of epithelial ovarian carcinoma. The aim of the present work was to study the cytotoxicity effect of hyaluronate targeted solid lipid nanoparticles (SLNs) of etoposide on SK-OV-3 cells. The cytotoxicity of the targeted and nontargeted SLNs of etoposide was compared to free drug on the SK-OV-3 cells by MTT assay method. The cellular uptake of the targeted and nontargeted nanoparticles containing sodium fluorescein was also studied. The difference of cell vitality between nontargeted nanoparticles and also targeted nanoparticles with free drug was significant. Targeted nanoparticles also caused more toxicity than nontargeted nanoparticles ( ). After 4 hours of incubating, the fluorescence was remarkably higher in the cells treated by targeted SLNs rather than nontargeted ones, and there was no observable fluorescence in cells incubated with pure sodium fluorescein. Hyaluronate targeted SLNs containing etoposide increased the cytotoxicity of etoposide on SK-OV-3 cells which may be a worthwhile potential method for reducing the prescribed dose and systemic side effects of this drug in epithelial ovarian carcinoma. 1. Introduction The epithelial ovarian carcinoma is one of the most fatal gynecological cancers across the globe. In spite of early recovery by surgical and chemotherapy treatments, the 5-year survival rate for the patients is only 13 percent. The database GLOBCAN related to the World Health Organization (WHO) has reported incidence of about 192000 cases in the world, in the year of 2000. 6000 cases of the mentioned cases have occurred in the UK, and 21000 cases in the U.S. For treating the disease, the tumor will be removed by surgical procedures and then chemotherapy would be started with platinum-based chemotherapy (cisplatin and carboplatin), which treating regime includes cisplatin and carboplatin with the drugs such as paclitaxel, docetaxel, cyclophosphamide, and doxorubicin. In some of the patients, the disease relapses after 6 months of chemotherapy; this condition is defined as platinum resistant, in which treatment would be continued with drugs such as topotecan and etoposide [1]. Etoposide, as other chemotherapy agents, has many side effects such as bone marrow suppression, granulocytopenia, thrombocytopenia [2], mucositis, moderate to severe esophagitis, hepatotoxicity, metabolic acidosis, and
Evaluating the cholesterol lowering and cytotoxicity of zaragozic acid, a novel therapeutic agent isolated from Coprophilous fungi
Sharma RJ, Patwardhan DG, Chaphalkar SR
International Journal of Pharmaceuticals Analysis , 2010,
Abstract: Coprophilous fungi were screened for the production of zaragozic acid. Out of the nineisolates obtained three isolates showed acid production during secondary screening followed by itspurification using organic solvents. The presence of zaragozic acid was confirmed by antimonytrichloride test (SbCl3) and its max at 190 and 249nm. Further the concentration of zaragozic acid wasdetermined by titrometric analysis, all the six isolates produced 75-80 mg L of acid .Cell titer 96 AQueous one solution reagent from Promege, USA was used to check the cytotoxicity of zaragozic acid.It was found that dosage up to 40 μl of cells did not prove toxic to the cells. The zaragozic acid was thenchecked for its cholesterol reduction activity. The cholesterol lowering effect of zaragozic acid oncholesterol synthesis was confirmed, 0.8 μg of cholesterol per gm of tissue was reduced by using 30 μlof zaragozic acid.
Evaluating the Effectiveness of Traffic Calming Devices: Using Simulation to Overcome Analytical Models Assumptions
International Journal of Traffic and Transportation Engineering , 2012, DOI: 10.5923/j.ijtte.20120103.03
Abstract: Schools are among the most significant traffic generators in urban areas. Recent statistics show that at least 60% of parents take their children to school by car, although up to 90% of children would like to go to school on foot or by bicycle. Parents feel the need to personally take their children to school in a ‘safe’ way, ignoring the fact that the increase in the number of cars leads to a further lowering of safety, which forces other parents to use cars as well. Thus, there are more cars than children in Europe.It is now widely recognized that it is desirable to install a series of traffic calming devices aimed discouraging the vehicular crossing of residential streets and encouraging motorists to behave in an safe way that is compatible with non-motorized mobility. However, the scientific literature lacks methods for the numeric assessment of the effects produced by the installation of these devices.The objective of this work is to develop a pedestrian safety indicator for evaluating the effectiveness of traffic calming measures. The indicator is calculated using a mathematical model to estimate the probability of conflict between a vehicle and a pedestrian crossing the road. This indicator is considered a measure of the pedestrian safety of the road.The values of the model variables are assessed by a micro simulation model of vehicle/pedestrian interactions in both the absence and presence of several traffic calming measures, to provide a quantitative assessment of the effectiveness of the speed control device.
The AWGN Red Alert Problem  [PDF]
Bobak Nazer,Yanina Shkel,Stark C. Draper
Mathematics , 2011,
Abstract: Consider the following unequal error protection scenario. One special message, dubbed the "red alert" message, is required to have an extremely small probability of missed detection. The remainder of the messages must keep their average probability of error and probability of false alarm below a certain threshold. The goal then is to design a codebook that maximizes the error exponent of the red alert message while ensuring that the average probability of error and probability of false alarm go to zero as the blocklength goes to infinity. This red alert exponent has previously been characterized for discrete memoryless channels. This paper completely characterizes the optimal red alert exponent for additive white Gaussian noise channels with block power constraints.
BIOTECHNOLOGY : AN OVERVIEW  [cached]
John I. Bruce
Bulletin of Health Research , 2012,
Abstract: Biotechnology as a science includes various aspects of the management and manipulation of biological systems. Recent advances in immunology, molecular biology, cell culture and other associated areas provide an opportunity for scientists to move biology out of the laboratory and into the realms of society. This has many implications which mankind on a whole may not be prepared to cope with at this time. This new capability has been referred to as "Biotechnology". Biotechnology has also been defined as "the integrated use of biochemistry, microbiology, and chemical engineering in order to achieve the capacities of microbes and culture cells". Genetic engineering which includes gene splicing and recombinant DNA-cloning is an example of a recent offshoot of biotechnology. Because of the advent of biotechnology, one can now think of the prospect of engineering tomorrows vaccines. In the past, vaccine development has been laborious and in many instances an unrewarding task. After years of effort only a handful of safe, effective vaccines have emerged. In the biotechnology arena, new methodologies and strategies for immunizing humans and domestic animals against infectious diseases are providing new hope for discovering successful vaccines. While most of the effort in the past has focused on viral vaccine development, attention is now being directed towards vaccines for protection against parasitic diseases. Currently, considerable effort is being made to develop vaccines for malaria, coccidiosis (in fowl), cholera, malaria, schistosomiasis and trypanosomiasis among others.
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