8,927 research outputs found
Analytical and experimental study of boiler instabilities due to feed-system - Subcooled region coupling
Instabilities occurring in forced-flow, electrically heated, downflow boiler due to feed system-subcooled region couplin
Alien Registration- Smith, Grace E M. (Durham, Androscoggin County)
https://digitalmaine.com/alien_docs/30150/thumbnail.jp
Motivations, expectations and experiences of Australian rural and regional planners
Despite playing an extremely important role in shaping communities, the role and contribution of planners is not widely understood or acknowledged. At the same time, there is a shortage of planners in Australia, especially in non-urban areas. Thus, though an online survey of 185 rural and regional planners, this research explores their motivations, expectations and experiences. Most enjoyed and felt confident in their role, explaining that they valued the relaxed family orientated rural lifestyle and the varied nature of the planning work. Although they sometimes felt isolated, the non-urban location provided quicker progression to senior roles, the ability to engage directly with the community and to see the consequences of their decisions. Only half felt their education had prepared them well for their role, citing gaps in terms of computerised modelling, team leadership and conflict resolution skills. Their feedback centred on providing a more practical course, focussing more on regional planning, and encouraging urban and rural experience placements. As the first study to quantifiably explore rural and regional Australian planners perceptions of their role and challenges, the findings illustrate current experiences, key planning challenges, perceived educational gaps and future priorities.Rural and regional planners; expectations; experiences; Australia
Dual Band Electrodes in Generator-Collector Mode: Simultaneous Measurement of Two Species
A computational model for the simulation of a double band collector-generator
experiment is applied to the situation where two electrochemical reactions
occur concurrently. It is shown that chronoamperometric measurements can be
used to take advantage of differences in diffusion coefficients to measure the
concentrations of both electroactive species simultaneously, by measuring the
time at which the collection efficiency reaches a specific value. The
separation of the electrodes is shown to not affect the sensitivity of the
method (in terms of percentage changes in the measured time to reach the
specified collection efficiency), but wider gaps can provide a greater range of
(larger) absolute values of this characteristic time. It is also shown that
measuring the time taken to reach smaller collection efficiencies can allow for
the detection of smaller amounts of whichever species diffuses faster. The case
of a system containing both ascorbic acid and opamine in water is used to
exemplify the method, and it is shown that mole fractions of ascorbic acid
between 0.055 and 0.96 can, in principle, be accurately measured.Comment: 34 pages, 8 figure
Altered sleep and EEG power in the P301S Tau transgenic mouse model
OBJECTIVE: Sleep disturbances are prevalent in human tauopathies yet despite the importance of sleep, little is known about its relationship with tau pathology. Here, we investigate this interaction by analyzing sleep and tau pathology throughout tauopathy disease progression in P301S human tau transgenic mice. METHODS: P301S and wildâtype mice were analyzed by electroencephalography (EEG)/electromyography at 3, 6, 9, and 11 months of age for sleep/wake time, EEG power, and homeostatic response. Cortical volume and tau pathology was also assessed by antiâphosphoâtau AT8 staining. RESULTS: P301S tau mice had significantly decreased rapid eye movement (REM) sleep at 9 months of age and decreased REM and nonâREM (NREM) sleep as well as increased wakefulness at 11 months. Sleep loss was characterized by fewer wake, REM, and NREM bouts, increased wake bout duration, and decreased sleep bout duration. Decreased REM and NREM sleep was associated with increased brainstem tau pathology in the sublaterodorsal area and parafacial zone, respectively. P301S mice also showed increased EEG power at 6 and 9 months of age and decreased power at 11 months. Decreased EEG power was associated with decreased cortical volume. Despite sleep disturbances, P301S mice maintained homeostatic response to sleep deprivation. INTERPRETATION: Our results indicate that tau pathology is associated with sleep disturbances that worsen with age and these changes may be related to tau pathology in brainstem sleep regulating regions as well as neurodegeneration. Tauâinduced sleep changes could affect disease progression and be a marker for therapeutic efficacy in this and other tauopathy models
Current State of Women in Academic Surgical Subspecialties: How a New Metric in Measuring Academic Productivity May Change the Equation
Obesity Prevalence and Dietary Intake of Antioxidants in Native American Adolescents
Antioxidants are well known for possessing anti-inflammatory properties, which can reduce the risk of chronic disease and obesity. However, very little research has been done to examine antioxidant intake among adolescent minority populations such as Native American adolescents. Our study examined the significance of antioxidant intake among Native American adolescents at an urban residential high school in Southern California. Our study population consisted of 183 male and female Native American adolescents, 14-18 years of age, representing 43 tribes from across the United States. Students' primary source of meals was provided by the school food service. Based on the BMI calculations, the rate of obesity within our population was 38% for males and 40% for females, more than two-fold the national rate indicated by NHANESIII data. We used the Harvard School of Public Health Youth/Adolescent Questionnaire (HSPH YAQ), a semi-quantitative food frequency questionnaire, to examine antioxidant nutrient intake and evaluate the differences in the intake between normal and obese weight students. Statistical analysis of the results showed that intakes of vitamins C, E, and lycopene were the antioxidant nutrients found to be significantly different between normal and obese weight students and intakes of these nutrients were found to be higher among normal weight students (p-values = 0.02451, 0.00847, and 0.04928, respectively). These results suggest that dietary intake of antioxidants could be increased among Native American adolescents. Further research is needed to confirm our findings and identify effective ways for school food service to incorporate antioxidant rich foods into school menus
Functional Jam Production from Blends of Banana, Pineapple and Watermelon Pulp
Functional jam from blends of banana, pineapple and watermelon pulp was produced and evaluated. The aim was to develop a locally but nutritionally rich, functional jam. Various blends of the fruit pulp were considered in order to select the best. The percentage compositions of the blends were 50:25:25; 25:50:25; 25:25:50 and 33.33:33.33:33.33 of banana, pineapple and watermelon pulps respectively. In addition to the pulp blends, 2.9% pectin produced from citrus peel was added together with citric acid, sodium benzoate and sugar. The entire mixture was heated at 110°C for 55 to enhance the viscosity of the blends. Proximate analyses, mineral analyses, brix, pH and Vitamin constituents of the sample were determined. The blend with the best result from the analyses was selected for rheological and sensory evaluations. The best blend was 25:25:50. The result of the proximate analyses of this best blend were 8.58% protein, 1.41% fibre, 0.38% ash, 3.92% fat, 2.52% moisture and 83.20% carbohydrate. The vitamin compositions were; 1.32 mg/100 g vitamin A, 8.22 mg/100 g vitamin C and 0.015 mg/100 g vitamin E. The pH was 4.16, viscosity 58.77 cp while the specific gravity was 1.016. The mineral compositions of the best blend were 0.34 ppm iron, 28.90 ppm sodium, 80.90 ppm potassium, 1.50 ppm calcium and 0.60 ppm magnesium
A study of factors related to primary grade spelling: correlations of factors studied.
Thesis (Ed.M.)--Boston Universit
The Hunt for Red 'Microba: Identification of Microorganisms involved in 'Red Heat' Contamination of Salt-Cured Hides
Content:
âRed heatâ is an industry term that describes the appearance of mostly red-pink coloured macroscopic microbial colonies on salt-cured hides and skins. Red heat-affected stock is undesirable as the resultant leather often shows obvious defects; but why this contamination is only superficial in other instances remains unclear. Previous work has focused on pigmented halophiles (âsalt-lovingâ microbes) isolated from curing salts as the primary culprit. However, the identity of causative agents remains unspecified. Also, the involvement of non-pigmented microbes, and of microbes native to hides and skins, could be better understood. Thus, an investigation of the microbial communities that inhabit untreated bovine hide, curing salt, unaffected salt-cured bovine hide, and red heat-affected cured hide is proposed to uncover the microbial agents responsible for this contamination. This project aims to define these microbial communities using both a culture-dependent and âindependent approach. Methods of microbe identification focus on marker gene amplification and sequencing. This is in contrast to earlier work which was restricted solely to phenotypic analyses. The 16S ribosomal RNA gene marker is used to identify members of Bacteria and Archaea, while the 18S and ITS2 regions of the fungal ribosomal RNA operon are targeted to detect fungi. Metagenomic amplicon sequencing using the Illumina MiSeq platform employs these same markers to determine taxonomic composition and relative abundance. Preliminary results from culturing identified different dominant species in curing salts screened for microbial growth. In agreement with earlier culture-based studies, these isolates were mostly pigmented, highly salt-tolerant members of the halophilic archaea of family Halobacteriaceae, as determined by marker gene sequencing. However, in agreement with more recent work within food preservation technology, nonpigmented isolates of halophilic archaea of genus Natrinema and bacterial genus Chromohalobacter were also found. It was also revealed that non-pigmented, quick-growing, salt-tolerant, proteolytic microbes were easily cultured from red heat-affected hide, most of the isolates were identified by marker gene sequencing as bacterial Pseudomonas halophila or Salicola. To determine red heat-causing microbes, future work involves the screening of isolates for extracellular enzyme activity; the most likely cause of red heat-associated damage. Sterile-salted hide samples will be inoculated with selected individual and combinations of isolates, and then further examined using confocal microscopy to check for reproducibility of red heat-associated damage.
Take-Away:
Different microbial species are found in different curing salts.
Not all microbes involved in 'red heat' contamination are pigmented.
The purpose is the possibility to overcome all the restrictions connected with the pin-wheel machine, the improvement of actual EN ISO methods of leather measurement and a better instrument to define
tolerances considering the couple leather-machine
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