460 research outputs found
Is information and communication technology (ICT) the right strategy for growth in Mexico?
Although empirical evidence available suggests that information and communication technologies (ICT) have positively contributed to important sectors of the Mexican economy, it is still unknown to which extent ICT have truly contributed to productivity among these sectors. The increasing implementation and imports of ICT technologies, the growing demand for ICT-skilled human capital and training, the rising level of wages and the large demand and adoption of these technologies seem to indicate a positive correlation between ICT implementation and economic growth in Mexico. To answer whether ICT may be a key strategy for economic growth in the Mexican economy is the main purpose of this work. --Information technology,total factor productivity,growth,knowledge,human capital,technology diffusion
Women’s Air Force Service Pilots: They Were Equal To Men in Training and Skill
During World War II (1941-1945), the United States manufacturing industry produced products for the war effort in extraordinary numbers. In the aircraft industry alone planes were built at such an alarming rate that manufacturers were rolling pursuit aircraft (P) or fighters, and bombers (B) at one an hour to a total of 13,738 P-40’s, 14,686 P-51’s, 12,692 B-17’s just to name a few. The Air Force2 needed skilled pilots to fly them from manufacturing plant to various Air Force bases. One group of pilots that would assists in this ferrying venture was the Women’s Airforce Service Pilots (WASPs). From 1942 through 1944 these women in training and knowledge, were equal to their male counterparts. Their ability to ferry any aircraft that was manufactured came because of two enterprising women, Jacqueline Cochran and Nancy Love. Even though these two women had an important part in getting the WASPs off the ground, the key ingredient to the success of the WASPs was their military training. During the twenty-four months that the WASPs were operating, they went through various training changes. At first because of the large amount of flying hours required the first set of women had only minimal military training depending on their experience. Then in 1943 the demand for more pilots reduced the required flying time for WASP applicants thus implementing a military structured training school just as the men. This revamped training included a ground school that included theory of flight, engines, navigation and instruments plus other subjects. They also had to increase their flying time on military aircraft starting with primary trainers (PT), then to basic trainers (BT), and finish with advanced trainers (AT). This additional training meant that the women would be in training for approximately four months to seven and a half depending on the time of entry to training. Because of this training the WASPs would be the equivalent of their male counterparts in ability to handle military aircraft. However not all writers chose to concentrate on training when writing about the WASPs
Development of Predictive Bioassessment Indices of Non-Perennial Streams and Rivers in the Arid Southwestern United States
Freshwater systems are a limited resource and must be managed to maintain or restore their ecological health. Bioassessments, which use the biota at a site to draw conclusions on a system’s ecological health, are commonly applied to freshwater systems. Freshwater bioassessment programs are typically only applicable in perennial systems (those which have surface water continually) and do not yet have an accepted role in assessing non-perennial streams in their dry phase. Although dry phase non-perennial streams that have a significant hydrological nexus with traditionally navigable waters navigable waters are protected under the state of California and national legislations, they cannot be assessed with bioassessment currently.
We sampled 106 dry streams in the arid southwestern United States and developed indices of taxonomic completeness (i.e., Observed to Expected or O/E indices) in dry streams to assess the effect of anthropogenic stress at these sites. We did this for three key assemblages in dry streams: channel-dwelling arthropods, riparian vegetation-dwelling arthropods, and bryophytes. We also explored different definitions ways of identifying reference sites and parameters related to index development to assess their effects on O/E indices’ performance. O/E indices using channel arthropods were the most responsive and sensitive to human activity, regardless of which reference definition or probability of capture threshold was used. Channel arthropods were the most responsive likely because they respond in a predictable way to stress. Vegetation-dwelling arthropods and bryophytes were absent at up to one quarter of all sites, which negatively affected index performance. The absence of these assemblages at reference sites yielded less responsive and unsuccessful indices developed with these assemblages.
The ecological status of dry streams can be determined from indices of taxonomic completeness when using channel-dwelling arthropods. Other taxa may not occur consistently enough across sites to produce responsive indices. Vegetation-dwelling arthropods should be omitted from future O/E studies because of their lack of response to stressors in stream channels. Further research should be conducted on moss and their response to local stressors because of their response to stress is difficult to predict
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An evaluation of the impact of maternal substance abuse on infant and child attachment
This study examined the impact and extent to which drugs and alcohol, consumed by mothers prenatally and perinatally, has affected their capacity to attach to their children. It examined the role the dependent variables measured (i.e. drug(s)/substance(s) abused, demographic information) played in the attachment process. Data was collected from mothers currently participating in the perinatal substance abuse treatment at the San Bernardino County Rialto program
Characterization of the stemphylium blight pathogens and their effect on lentil yield
The disease stemphylium blight has become common in lentil fields in Saskatchewan, but the effect of this disease on developing lentil plants, has not been studied under field conditions. Even though Stemphylium botryosum is suspected to be the pathogen causing stemphylium blight in lentil around the world, there is no confirmation of the pathogenic species involved in stemphylium blight of lentil in Saskatchewan. The objectives of this study were to determine the effect on lentil seed quantity and quality of S. botryosum infection at the seedling, the early-flowering, the mid-flowering or the podding stages, and to characterize the pathogen or pathogens causing stemphylium blight in Saskatchewan lentil fields.
Three field experiments were conducted over two years using green polyethylene low tunnels to create conducive environments and control the timing of infection. Cumulative disease severity, measured as area under the disease progress curve, in lentil treatments inoculated at the seedling stage was higher compared to treatments inoculated at later growth stages or to uninoculated control treatments, in which some stemphylium blight developed due to natural inoculum. Neither the amount of harvested seed, nor seed weight or seed size were reduced compared to the uninoculated control, even though disease severity was higher in inoculated versus uninoculated treatments. Seed infection levels of 2.6 to 3.4% in seed harvested from treatments that were inoculated at the seedling, early and mid-flower stages were significantly higher than those observed in seeds from uninoculated control treatments (0.6%) or from treatments inoculated at podding (1.2%).
Field isolates of Stemphylium spp. were compared to the ex-type isolate by morphology, and additionally to sequence data of five Stemphylium spp. and one Alternaria sp. obtained from GenBank by molecular phylogenetic analyses of the internal transcribe spacer (ITS) and the glyceraldehyde 3 – phosphate dehydrogenase (gpd) gene regions. Morphology of colony and conidia were not informative since features overlapped except for three isolates. Results of the molecular phylogenetic analyses revealed that S. botryosum is one of two possible Stemphylium spp. involved in the development of stemphylium blight in lentil. The three isolates with different morphology were also consistently clustered as a species distinct from the Stemphylium species.
Although yield loss could not be demonstrated here, further studies on the epidemiology of the pathogens causing stemphylium blight in Saskatchewan lentil fields are warranted in view of the fact that more than one candidate species was identified as the causal agent
Zero Waste Campus Dining
Cal Poly Campus Dining has a goal of becoming a zero waste entity by providing their customers with alternative methods of disposing their trash. Their current operations produce waste, specifically their methods of packaging the food. Campus dining plans to be more sustainable by providing their customers with reusable containers. The objective of this implementation is to reduce waste produced from one-time use, disposable food containers. The success criteria for the desired system is based around the ability to track and measure the reusable containers to prevent further waste, while providing the user an accommodating environment to ensure they will choose the sustainable option. Our experiment was designed using three objectives: usability, readability, and durability. In order to best accommodate the Cal Poly community, one of the supporting teams calculated the number, and approximate locations, of the return bins that will be collecting the reusable containers. Another supporting team worked on modifying the trash bins currently used at their operations to collect the reusable containers, in order to provide a seamless transition for the customers.
Based on the client’s suggestions, we tested two methods of tagging in order to track and measure the reusable containers. The methods tested were barcode and radio frequency identification (RFID) tags. Tests were performed on the containers while containing both tags to measure readability. The tags were read using a direct scanner and an indirect scanner. The ultimate goal was to utilize an indirect scanner in order to avoid an additional task for the current Campus Dining employees. The containers were also tested under different conditions, such as placing food inside the container, to test the readability of the tags. The results of the RFID tags ranked far superior when compared to the barcode tags. The measured readability with an indirect scanner of RFID and barcode tags was 100% and 4.16%, respectively. The tags were then tested for durability. The reusable containers would need to be washed after each use through Cal Poly Campus Dining’s dishwasher, the Stereo Commercial Dishwasher model STPCW-ER. A sample of eleven RFID tagged containers was processed through fifty wash cycles. A quality check was performed to find ten of the eleven containers had no water infiltration on the RFID tag, providing a durability success rate of 91%. The tagged containers were tested again for readability after the fifty wash cycles and all of the tags were read, including the tag that was exposed to water.In conclusion, it is our recommendation to move forward with the zero waste initiative in replacing the current dining disposable containers with RFID tagged reusable containers. The tags will be able to withstand the current cleaning methods, while providing accurate readings when returned into the designated bins. Campus dining will be able to avoid further waste by removing the need to purchase 177,200 disposable containers annually. A ten-year cost analysis calculated the cost of the implementation to be approximately 55,500, and a depreciated asset cost of 450,000 by the end of ten years. In contrast, the current system, using the disposable containers, will result in a cumulative cost of 50,00
Bimetallic Pt-Pd co-catalyst Nb-doped TiO2 materials for H2 photo-production under UV and Visible light illumination
In this work we synthesized a series of binary PtPd co-catalysts supported on a Nb-doped TiO2 support. The catalytic solids and corresponding monometallic reference systems are characterized using X-ray diffraction, X-ray photoelectron, and UV–vis spectroscopies, together with microscopy and porosimetry tools. Such characterization was able to show the formation of PtPd alloy particles in the bimetallic catalysts. The mono and bimetallic TiO2-based powders were tested in the photo-production of hydrogen from methanol:water mixtures under UV and visible illumination conditions. Analysis of catalytic properties was carried out through the measurement of the optical properties of the materials and the calculation of the true quantum efficiency parameter. Results indicate that the PtPd co-catalysts have superior performance that the Pt and Pd monometallic counterparts both under UV and visible illumination conditions. Optimum performance was achieved with a material having a Pt:Pd 1:1 atomic ratio. A remarkable increase in the use of the visible range and thus in sunlight utilization is achieved with the 1:1 Pt:Pd bimetallic system with respect to the monometallic counterparts. The evolution of the bimetallic co-catalysts under reaction conditions as well as their key properties to interpret photo-activity were analyzed with the help of the above mentioned techniques as well as photoluminescence spectroscopy and an in-situ infrared analysis of the materials under reaction conditions. Results point out the critical role that both PtPd alloying and the metal-support interface play in the reaction
Recent progress in the quantitative assessment and interpretation of photoactivity
The development of the photo-catalysis field is limited by a
deficient quantitative assessment of photo-activity. The interplay
between mass and momentum transport together with radiative
transfer phenomena taking place at any photo-catalytic reaction
or process makes complex such quantitative assessment. To
reach this goal, the review studies the measurement, meaning,
and analysis of three types of observables. The first family of
observables has the reaction rate and closely connected
observables as the turnover frequency as central pieces.
The second family owns the so-called efficiency observables,
starting from the photonic yield and quantum efficiency of the
reaction and ending in the global efficiency of the process. Finally,
the review studies kinetic constant observables. The contribution
focusses on most rencet contribution analyzing these
observables in terms of their (adequate) measurement conditions
and physico-chemical interpretation, in order to unveil their full
potential in the context of the photo-catalysis field.MCIN/AEI PID2019-105490RB-C31ERDF A way of making EuropeEuropean CommissionConsejo Nacional de Ciencia y Tecnologia (CONACyT) SENER-CONACyT 117373UGR PPJIA2019-0
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