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Beyond Protecting Genetic Privacy: Understanding Genetic Discrimination Through its Disparate Impact on Racial Minorities
At the very end of the last century, scientists produced the first draft of the whole human genetic sequence. But that was just the first step; the hard work of the first few decades of this century will be to learn more about how to apply genetic information to improve health. As the pace of technological development accelerates and we learn more about what genetic variations mean about individual human characteristics and health risks, so too does the risk and consequences of the misuse of such information become more significant. The principal answer to this challenge has been to safeguard privacy by constructing legal and technical barriers that conceal and anonymize genetic information. While it may be a worthwhile objective, ultimately privacy protections will likely fail in practice. If this is so, how can we prevent genetic information from being used to categorize, stigmatize, and subordinate? This Note approaches this problem by analyzing the African American experience with genetic discrimination in the United States. African Americans have confronted the adverse consequences of genetic research in ways that can serve as a foundation to understand future threats posed to racial minorities and everyone in society, as genetic testing increases in prevalence and the privacy of genetic information is unable to be protected. Studying the real history of genetic discrimination, rather than merely speculating about what may happen, can point toward policy solutions that go beyond ―genetic privacy.‖ As genetic information becomes more plentiful and valuable, policies to prevent the misuse of that information will benefit everyone, regardless of race or ethnicity
Types of Lasers and Their Applications in Pediatric Dentistry
 Laser technology has been recently introduced into the dental field with the idea to replace drilling. Having a less painful first dental experience by the use of modern instruments like laser can be an efficient preventive and therapeutic strategy in pediatric dentistry. Pedodontists need to learn the new less invasive technologies and adopt them in their routine practice. This study aimed to review the available types of lasers and their applications in pediatric dentistry.An electronic search was carried out in IranMedex, InterScience, Scopus Science Direct, PubMed,ProQuest, Medline and Google Scholardatabasesto find relevant articles published from 2000 to 2014. Relevant textbooks were reviewed as well.Laser can be used as a suitable alternative to many conventional diagnostic and therapeutic dental procedures.It is especially efficient for caries detection and removal, pulp therapy, lowering the risk of infection, inflammation and swelling and reducing bleeding. On the other hand, due to minimal invasion, laser treatment is well tolerated by children. Improved patient cooperation leads to higher satisfaction of the parents, dentists and the children themselves
Physical properties of charred pellets after two months of storage
Six types of charred pellets: canola straw, willow, bagasse, wheat straw, switchgrass and miscanthus, were stored for a period of two months at room temperature 25±2 °C in sealed containers. The tests were part of off gassing experiment on charred and uncharred pellets. The following physical properties of the pellets were measured: bulk density, individual pellet density, Individual pellet dimensions were similar between samples but the pellet mass ranged from 0.79 g for switchgrass to 1.13 g for bagasse pellet.
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Off-gassing of charred pellets during storage
The off-gassing tests for six types of charred pellets: canola straw, willow, bagasse, wheat straw, switchgrass and miscanthus, were conducted at room temperature 25±2 °C in sealed storage containers. Pairs of 2-litre sealable glass containers were filled with 800 g of each sample to approximately 75% of the container volume. One container contained charred pelles. The other container contained uncharred (untreated pellets). The two glass containers were sampled in alternate weeks for CO2, CO, O2, and CH4.
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Biomass Torrefaction Process Review and Moving Bed Torrefaction System Model Development
Torrefaction is currently developing as an important preprocessing step to improve the quality of biomass in terms of physical properties, and proximate and ultimate composition. Torrefaction is a slow heating of biomass in an inert or reduced environment to a maximum temperature of 300°C. Torrefaction can also be defined as a group of products resulting from the partially controlled and isothermal pyrolysis of biomass occurring in a temperature range of 200–230ºC and 270–280ºC. Thus, the process can also be called a mild pyrolysis as it occurs at the lower temperature range of the pyrolysis process. At the end of the torrefaction process, a solid uniform product with lower moisture content and higher energy content than raw biomass is produced. Most of the smoke-producing compounds and other volatiles are removed during torrefaction, producing a final product that will have a lower mass but a higher heating value. An important aspect of research is to establish a degree of torrefaction where gains in heating value offset the loss of mass. There is a lack of literature on torrefaction reactor designs and a design sheet for estimating the dimensions of the torrefier based on capacity. This study includes a) conducting a detailed review on the torrefaction of biomass in terms of understanding the process, product properties, off-gas compositions, and methods used, and b) to design a moving bed torrefier, taking into account the basic fundamental heat and mass transfer calculations. Specific objectives include calculating the dimensions like diameter and height of the moving packed bed for different capacities, designing the heat loads and gas flow rates, and developing an interactive excel sheet where the user can define design specifications. In this report, 25–1000 kg/hr are used in equations for the design of the torrefier, examples of calculations, and specifications for the torrefier
Value added processing of dehydrated and suncured alfalfa
Non-Peer ReviewedA pilot scale pellet mill was used to produce pellets using ground alfalfa leaf and stem fractions. Both suncured and dehydrated alfalfa chops were used in the experiments. The moisture content of the suncured and dehydrated chops was 8.4 and 9.6% (wb), respectively. A stack of two square sieves with different opening sizes and a pan were used to separate leaf and stem fractions. The leaf and stem fractions were further segregated into two sample lots and ground in a hammer mill using two screen sizes of 3.20 mm (1/8 in.) and 1.98 mm (5/64 in.). The leaf and stem fractions from each sample lot of same grind sizes were combined to get five different samples with leaf content ranging from 0% to 100% in 25% increments. The moisture content and temperature of the samples were raised to 10-11% (wb) and 76oC, respectively, in a double chamber steam conditioner prior to the pelleting operation. The temperature of material was further raised to 95oC in the pellet mill due to the friction between its roller-die assembly.
Average particle sizes of sample lots were determined. Temperature and moisture content of samples after various pelleting stages were recorded. High durability pellets were produced using fractionated suncured alfalfa irrespective of grind size (except for 100% stems, which was low). Durability fluctuated between high and medium range for dehydrated alfalfa (except for 100% stems, which was low). Dehydrated alfalfa produced pellets with greener color, while suncured alfalfa produced harder pellets
Woody Feedstock Pretreatments to Enhance Pyrolysis Bio-oil Quality and Produce Transportation Fuel
Lignocellulosic biomass as a potential renewable source of energy has a near-zero CO2 emission. Pyrolysis converts biomass to a liquid fuel and increases the energy density and transportability. The pyrolysis bio-oil shows promising properties to substitute the conventional fossil fuels. But, unprocessed biomass is low in bulk and energy density; high in moisture; heterogeneous in physical and chemical properties, highly hygroscopic and difficult to handle. That is why the biomass needs mechanical, chemical and/or thermal pretreatments to turn into a more homogeneous feedstock and minimize the post-treatment fuel upgrading. This chapter explains the effects that various pretreatments such as size reduction, drying, washing and thermal pretreatments have on the quality and quantity of bio-oil. Washing with water or acid/alkali solutions extracts the minerals that consequently reduces the ash and shortens the reactor clean-out cycle. Torrefaction is gaining attention as an effective pretreatment to modify the quality of biomass in terms of physical and chemical properties. Torrefaction produces a uniform biomass with lower moisture, acidity and oxygen contents and higher energy density and grindability than raw biomass. Pyrolysis of torrefied biomass produces bio-oil with enhanced compositional and physical properties such as a higher heating value and increased C (lower O/C ratio)
Recent developments in the disinfestation of Hessian fly puparia in baled hay
Non-Peer ReviewedTo comply with phytosanitary and quarantine regulations, baled hay has to be disinfested of Hessian fly [Mayetiola destructor (Say)] puparia before exporting to Japan. Several laboratory and field trials to destroy Hessian fly puparia in baled hay were either successful or unsuccessful. After the unsuccessful attempt to destroy Hessian fly puparia in the last confirmatory field test, laboratory tests were performed to identify any problem areas and validate the possible causes of insect survival during the field trials. Three different quantities of infested wheat seedlings contained in mesh bags designated types “A”, “B” and “C” test cages were used in the tests. Moisture content of the infested wheat seedlings contained in test cages was determined by the oven method. A recirculating forced-air dryer unit was used to determine the time required for the temperatures within the bulk of the infested wheat seedling to reach 60oC, and to confirm the thermal kill temperature for the Hessian fly puparia when the puparia were still located in the
seedlings intact. Three thermocouple sensors were inserted into the bulk of the wheat seedlings to monitor the temperature. Three replicates were conducted for each test cage size. Heat disinfestation and control (unheated and heated) tests were conducted in a heat treatment unit on timothy hay bales. Thermocouple sensors were inserted into the bales and the wheat seedlings to monitor their temperature profiles. The heating time was influenced by the packing density of the infested wheat seedlings contained in the test cages. The survival of the Hessian fly puparia was influenced by the moisture content and the packing density of the infested wheat seedlings
Improved gas-solid mixing and mass transfer in a pulsed fluidized bed of biomass with tapered bottom
To improve fluidization quality and mass transfer rate of biomass fluidized beds with pulsed gas flow, an existing fluidized bed with rectangular cross-section area was modified with the insertion of a tapered bottom section such that dead zones observed in the original design could be eliminated. Batch drying tests were performed as an indirect indicator of gas-solid contact efficiency and mass transfer performance. Compared to the original design, biomass particles could be fluidized at a wider range of gas pulsation frequencies with significantly reduced channeling and gas bypassing in the new tapered design. Faster drying and thus improved mass transfer were also observed in the tapered bed, as reflected by both the instantaneous drying rate and final moisture content of the sample. A simple particle drying model was applied to fit measured drying curve, and the results showed that under the same operating condition fluidized bed with a tapered bottom had a higher effective vapor diffusion coefficient compared to the original design
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