Study on the acid hydrolysis of Peat: 1. extraction of carbohydrates

Peat and its derived products such as peat extracts or hydrolysates offer a variety of possibilities as raw materials for the development of chemical and biochemical processes. Acid hydrolysis of peat yields soluble carbohydrates which can be utilised as fermentation media. In this work, Sphagnum peat moss was hydrolysed under various conditions of H₂SO₄ concentration, retention time, temperature, peat concentration, peat particle size distribution and original moisture content in the peat. The results suggest that mild conditions of hydrolysis, which will minimise possible negative effects on other nutrients available in peat, are adequate for the release of the carbohydrates present in peat. It was found that peat particle size distribution and original moisture content as well as peat concentration will also affect the yield of carbohydrates obtained.     

The roles of humans and computers in distributed planning for dynamic domains

The requirements and issues associated with computational representations for planning extend beyond those apparent in real-time control, where a substantial, existing research literature informs designers. To assist in the identification of requirements for planning representations, this paper provides two resources: (1) a theoretical foundation drawn from computer science and (2) illustrations of representations and corresponding work practice for real-time control and planning for the US Shuttle program. Together, these resources illustrate the human role in the planning process, and the need for work practices and information that combine to assist human operators in interpreting a representation that is loosely coupled to the physical world while shared among and modified by multiple participants in the planning process.

Suicide attempters within a delinquent population.

Contrasted 30 13–15 yr old delinquents who had attempted suicide with 120 delinquent controls. Multiple regression analyses showed that suicidal ideation, depression, gender, a tendency to act out, conflict with parents, childhood hyperactivity, and the interactions of gender with depression and with acting out accounted for 49% of the variance in suicide attempts. Females were found to attempt suicide 2? times as often as males. Females were also more likely to attempt suicide when depressed than were similarly depressed males. Male and female delinquents who engaged in a high level of acting out were equally likely to attempt suicide, but females who did not act out were more likely to attempt suicide than males who did not act out. Similarities between these adolescent attempters and adult suicide attempters described in the literature are discussed. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Climatic considerations in school building design in the hot–humid climate for reducing energy consumption

Energy-conscious design of school buildings can contribute to significant energy savings and improve the students’ learning environment. The purpose of this research is to formulate design recommendations for school buildings in the hot–humid climatic zone and assess the influence of different design variables on their energy consumption. A base-case classroom was constructed by taking commonly used values for each design variable. Using computer simulation techniques, these variables were modified one by one to find the value that minimized energy consumption, while keeping thermal and visual comfort in the room. Based on these tests, the recommended value for each design variable to achieve a high performance classroom, was determined. Comparative tests were done to determine which variables have greatest impact on the energy consumption and thermal comfort in the classroom, and how their absolute influence depends on the order of implementation of each improvement. A complex interdependence among the design variables was found, but strong conclusions for energy savings could still be reached.     

Alternative carriers for remote renewable energy sources using existing CNG infrastructure

Optimal locations of renewable energy sources are often remote relative to consumers and electricity grids. In contrast, some existing CNG pipelines pass through optimal renewable energy harvesting regions. The growing interest in the possibility of using geothermal energy in central Australia has created a need to assess the economic, technical, and environmental viability of converting remote renewable energy to fuel for transport using existing CNG pipelines, and to compare this alternative with that required to construct new high-capacity electricity transmission lines. This assessment is reported, using first the conversion of electricity to hydrogen, and then conversion of the hydrogen to methane. The paper also compares the alternative of direct injection of hydrogen into existing CNG pipelines to create “hythane” (HCNG). An economic assessment showed that the relative capital and operating costs are sufficient make the alternative carrier prospect worthy of further consideration.     

Theoretical calculation of product contents: battery and cathode ray tube examples

Most product environmental assessments are based on manufacturer-supplied data on the material content of the product. This paper explores the potential for the material content of key components to be estimated with theoretical calculations. Two examples, the amount of cadmium in a nickel-cadmium battery and the amount of lead in a TV or computer CRT monitor, are developed. Both an upper and a lower limit on the amount of cadmium in a nickel-cadmium battery are calculated on the basis of the battery's chemical reaction. The amount of lead shielding needed in a TV or CRT computer monitor is estimated on the basis of the potential difference through which electrons are accelerated and the absorption length of photons in lead. Such calculations can be used as benchmarks in product environmental assessments, providing validation of manufacturer-supplied data and providing insight into the composition and design of products.     

Phenotypic and genetic characterization of antimicrobial resistance in Salmonella serovars isolated from retail meats in Alberta, Canada

This study determined the prevalence of Salmonella serovars, antimicrobial resistance (AMR) and resistance genes in Salmonella isolated from retail meats purchased in Alberta, Canada. Samples were collected during one year period (May 2007–April 2008) on weekly basis from 19 census divisions in Alberta. A total of 564 samples including chicken (n = 206), turkey (n = 91), beef (n = 134) and pork (n = 133) were purchased. Salmonella were recovered from chicken (40%), turkey (27%) and pork (2%) samples and was not found in ground beef. A total of 21, 8, and 3 different serovars were recovered from chicken, turkey and pork meats, respectively. Salmonella Hadar was most common in chicken whereas S. Heidelberg was common in turkey meat. Overall 29% (32/110) of isolates were susceptible to tested antimicrobials and resistance to ciprofloxacin, amikacin and nalidixic acid was not found in any isolate. Multiresistance (≥2 antimicrobials) was found in 56% of isolates. Resistance to amoxicillin–clavulanic acid (AMC), ceftiofur (TIO), and ceftriaxone (CRO) was found in about 21% of chicken and 25% of turkey isolates. Resistance to either of tetracycline (TET), streptomycin (STR) or ampicillin (AMP) was unconditionally associated with S. Hadar but resistance to either of TET, AMP, AMC, TIO, CRO or cefoxitin was associated with S. Heidelberg. The strA/B (42% isolates), tet(A) (28% isolates), bla_CMY-2 (21% isolates) and bla_TEM (17% isolates) were the most common resistance genes found. The bla_CMY-2 and bla_TEM genes were unconditionally associated with S. Heidelberg; tet(A) and strA/B with S. Hadar and tet(B) gene with S. Kentucky. The strA/B genes were not associated with S. Heidelberg. Our data suggests that the prevalence of Salmonella serovars varied by the meat type and that AMR and resistance genes varied by the Salmonella serovars.     

Blueberries and Their Anthocyanins: Factors Affecting Biosynthesis and Properties

Abstract: Blueberry is one of the most popular fruits in North America and rich in anthocyanins. Its content in anthocyanins contributes to the health‐beneficial effects of blueberry against several chronic diseases including cardiovascular disorders, neurodegenerative diseases, diabetes, and cancer. This paper summarizes various facts presenting blueberry as a fruit with huge potential for increased future consumption as a health‐enhancing food. Factors affecting the biosynthesis of the various anthocyanins in blueberries, including agronomic and genetic factors, and the possible pathways of biosynthesis of the major anthocyanins present in this plant are discussed. The important health‐beneficial effects associated with blueberry anthocyanins, properties of these anthocyanins leading to the beneficial effects, and food processing parameters leading to the depletion of the amounts of anthocyanins present in the final processed products are also briefly discussed. Furthermore, the general methods of extraction and analyses that have been reported for being successfully applied to blueberry anthocyanins are also reviewed. Practical Application: Blueberries are well known for their nutritional and beneficial health effects, however, information concerning the physiology behind the blueberry beneficial effects is still lacking. There is little or no information on the characterization of growing conditions on anthocyanins in blueberries and research is lagging behind on advanced methods of extracting blueberry anthocyanins.