Homo Economicus: Rare earth profiling

This paper discourses the IMF graph on monthly tin prices between May 2008 and May 2013, indicative of a high volatility on price, typical of rare earth metals. The sharp increases and steep decline on monthly prices, state the absence of equilibrium or stability between the supply side and the demand side. For that reason, price fluctuation is correlated to the oligopolistic market behaviour characterised of the World metals industry, dominated by a handful of suppliers having apparent control on pricing movements

Permeability of DOPC bilayers under photoinduced oxidation: Sensitivity to photosensitizer.

The modification of lipid bilayer permeability is one of the most striking yet poorly understood physical transformations that follow photoinduced lipid oxidation. We have recently proposed that the increase of permeability of photooxidized 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) bilayers is controlled by the time required by the oxidized lipid species to diffuse and aggregate into pores. Here we further probe this mechanism by studying photosensitization of DOPC membranes by methylene blue (MB) and DO15, a more hydrophobic phenothiazinium photosensitizer, under different irradiation powers. Our results not only reveal the interplay between the production rate and the diffusion of the oxidized lipids, but highlight also the importance of photosensitizer localization in the kinetics of oxidized membrane permeability

Flight descent trajectory fuel efficiency on short segments

The work substantiates the strait in runway approaches LOC CDA R13 and VOR CDA R31 with manipulation of BADA total energy equation using ICAO rule of thumb for fuel burn reduction. This case study of fuel efficiency by flight trajectory on a short busy route DOH-AUH as proof of theorem of earlier study findings. After the application and analysis of four default equations and values on fuel reduction, the application random between upper and lower limits defines a fuel burn reduction of 219 kg for each descent trajectory for flights DOH-AUH. A graphical representation of this is seen on the Fuel Reduction Chart. Annual fuel savings come to 696 538 kg, using the flight distribution schedule of Qatar and Etihad in the Abu Dhabi International Airport. The corresponding emissions reduction on CO2, CH4, N2O, NOx, CO, NMVOCs and SO2 are also stated. Subsequently, in a short route the fuel burn in a descent trajectory represents a larger portion of the flight expenditure. The fuel burn in the descent trajectory for each flight en route DOH-AUH, constitutes 6.4 percent of the total fuel consumption and is not typical to the design range and standard payload that derived for long hauls

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Cockrell School of EngineeringCockrell School of Engineerin

Addition of Cleaved Tail Fragments during Lipid Oxidation Stabilizes Membrane Permeability Behavior

Lipid oxidation has been linked to plasma membrane damage leading to cell death. In previous work, we examined the effect of oxidation on bilayer permeability by replacing defined amounts of an unsaturated lipid species with the corresponding phospholipid product that would result from oxidative tail scission of that species. This study adds the cleaved tail fragment, better mimicking the chemical results of oxidation. Permeability of PEG12-NBD, a small, uncharged molecule, was measured for vesicles with oxidation concentration corresponding to between 0 and 18 mol % of total lipid content. Permeability was measured using a microfluidic trap to capture the vesicles and spinning disk confocal microscopy (SDCM) to measure the transport of fluorescent PEG12-NBD at the equatorial plane. The thicknesses of lipid bilayers containing oxidized species were estimated by measuring capacitance of a black lipid membrane while simultaneously measuring bilayer area. We found that relative to chemically modeled oxidized bilayers without tail fragments, bilayers containing cleaved tail groups were less permeable for the same degree of oxidation. Curiously, membrane capacitance measurements indicated that the addition of tail fragments to chemically modeled oxidized bilayers also thinned these bilayers relative to samples with no tail fragments; in other words, the more permeable membranes were thicker. Above 12.5% chemically modeled oxidation, compositions both with and without the cleaved tail groups showed pore formation. This work highlights the complexity of the relationship between chemically modeled lipid bilayer oxidation and cell membrane properties

Identification of occupational hazards present in rice farming in the Municipality of Naic, Province of Cavite

Descriptive-quantitative was the research design of the study. The total number of respondents was 285 computed using on Slovin\u27s formula. Data was collected through interview with the use of survey-questionnaires that served as guide to facilitate structured data gathering. Frequency and percentage were used to interpret the data. Occupational hazards were identified based on two (2) general factors intrinsic and extrinsic. Under intrinsic factors, males as compared to females and who were also in the middle age group were more vulnerable to injuries; informal education also imposed risk for work-related hazards as different farming roles require specific level of skills and knowledge; years in farming (more than 15 years), longer working hours which are prevalent among male rice farmers and less than six hours of sleep spent at night contribute to work hazards among Naic rice farmers. Medical history presented that musculoskeletal disorders are the most prevalent among Naic farmers, primarily low back pain as awkward postures like stooping, squatting in longer work hours predisposed them to this medical condition. Vices tended not to pose significant hazard to Naic rice farmers as majority of them are non-smokers and non-drinkers. Findings on farming roles showed that most number of farmers were participating on crop management and exposed them to the use of different chemicals. Extrinsic factors include farm operations that despite the use of machinery, majority of the physically demanding job like land preparation, planting and harvesting remain manual which puts more occupational risk for farmers; exposure to chemicals showed that majority of the farmers are still using types II and III which are under warning and harmful and caution classifications respectively; use of protective clothing were less than 50% among Naic rice farmers which may cause hazards with regards to their exposure to farm chemicals and even contact with dangerous animals