638 research outputs found
Automatic identification and enumeration of algae
A good understanding of the population dynamics of algal communities is vital in many ecological and pollution studies of freshwater and oceanic systems. Present methods require manual counting and identification of algae and can take up to 90 min to obtain a statistically reliable count on a complex population. Several alternative techniques to accelerate the process have been tried on marine samples but none have been completely successful because insufficient effort has been put into verifying the technique before field trials. The objective of the present study has been to assess the potential of in vivo fluorescence of algal pigments as a means of automatically identifying algae. For this work total fluorescence spectroscopy was chosen as the observation technique
Generalization of joint attention: Using parent child interaction therapy to program social skills in children with developmental disorders
Generalization of social behaviors is a vital component of human behavior. Children with Autism Spectrum Disorder often show symptomology that includes impairment in social behavior and failure to generalize behavior on the whole. Initiation of joint attention is a social behavior that can be understood as a behavior cusp and worthy of intervention to promote development. Parent-Child Interaction Therapy has been studied in recent years for its efficacy in treating some dimensions of Autism Spectrum Disorder in children and adolescence. The current study sought to explore the efficacy of Parent-Child Interaction Therapy in promoting the generalization of initiation of joint attention in children with Autism Spectrum Disorder across adult/child dyads. Data showed that PCIT was both effective in producing initiation of joint attention and in producing generalization of joint attention
Canine Support Program: Student perceptions and preferences at a regional university and implications for health, well-being, and student support enhancements
Issue Addressed: Canine Support Programs (CSPs) are a potential solution to growing university student support demands. While current studies focus on the impacts of CSPs, there is limited understanding of the views and expectations of tertiary students about CSPs. This study explored the perceptions and preferences of students in an Australian regional university about CSPs.
Methods: A questionnaire with multiple choice and open-ended questions surveyed residential students' perspectives about CSP. Data were analysed using descriptive statistical tests and thematic analysis for open responses.
Results: Majority (98%) of participants (sample n = 48) would support a CSP on campus. Frequent, small-group interactions of ≥15 min involving physical contact were preferred. Dog disposition, welfare-trained handlers, and veterinary certification were important aspects of program safety. Participants strongly agreed a CSP would improve mental health and well-being, relieve stress, reduce feelings of homesickness, provide support, comfort, and enable social interactions.
Conclusion: There is strong support among the study population for CSP to be established on campus. This study supports earlier research that CSP has benefit potential for new, stressed, and/or students who love dogs. The preferences of students should inform program design to enhance utility and impact. This aligns with Health Promoting Universities and College's Okanagan Charter principle of ‘engaging student voices’. More institutional awareness and support for CSPs will be necessary for integration.
So What?: This study reveals the need for tailored and creative student support beyond traditional offerings including those that focus on student well-being and social initiatives. CSPs can be utilised as an advocate, enabler, and medium for mental health promotion action and well-being support for tertiary students; thereby, contributing to the ‘Health Promoting University’ agenda in Australia. It also reinforces the need for a Health in All Policies approach to be incorporated into our tertiary education sector. Future actions should focus on improving institutional awareness, support, and sector implementation
A review of juvenile redclaw crayfish Cherax quadricarinatus (von Martens, 1898) Aquaculture: global production practices and innovation
The Australian Redclaw crayfish, Cherax quadricarinatus, has been the subject of aquaculture development for more than 3 decades. Farm production from Australia and from around the world for this species has been relatively low, as suitable production technology continues to develop. The production of redclaw juveniles for the purpose of stocking to ponds for on-growing to marketable size, has been a particular constraint and new approaches to breeding and mass production of craylings have provided renewed impetus to industry expansion. This paper reviews the literature concerning redclaw juvenile production and provides a status report of current practices and innovations that may support further expansion of redclaw aquaculture
Determining suitable thermal regimes for early instar redclaw juveniles, Cherax quadricarinatus (von Martens, 1868) (Decapoda, Parastacidae), for a proposed nursery phase
Modern, intensified aquaculture typically involves three production phases; hatchery, nursery, and grow-out. For redclaw crayfish aquaculture however, such delineation has been ill-defined. Farming of redclaw was initiated based on the putative beneficial physical and biological attributes of the species, which suggested production methods would be relatively simple. The simple approach proved to be inefficient and only partially effective, which hindered industry development. Hatchery technology now exists to supply seed stock for grow-out, but hatchery production is variable, and the performance of hatchery reared juveniles is inconsistent. A nursery phase has been proposed between hatchery production and grow-out of approximately 3 weeks duration, sufficient to allow 2 or more moults. An important primary parameter in the proposed nursery phase is the thermal regime that will support optimum survival and growth. This study quantified the effect of temperature on the growth and survival of redclaw juveniles for a 22-day nursery phase. Temperature had a statistically significant effect on the survival of juveniles, whereby, the high temperatures were associated with high mortality, and the lower temperature treatments were associated with very low mortality. Survival was 98 to 100% for craylings held at temperatures between 18 degrees C and 22 degrees C, and between 0% and 6% for craylings at temperature treatments of 25 degrees C to 32 degrees C. Mortalities within treatments between 25 degrees C and 30 degrees C, primarily occurred from day six to day eleven, corresponding with the initiation of moulting. Change of mass of crayfish was significantly higher with increasing temperature between 18 degrees C and 22 degrees C and at individual weights that suggest they had completed a moult. This study suggests a water temperature of 22 degrees C is optimal for survival and growth in a nursery phase
Evaluation of four practical diets on the growth and survival of juvenile redclaw, Cherax quadricarinatus (von Martens, 1868)
Redclaw, Cherax quadricariatus (von Martens) has shown promise as an aquaculture species but commercial development has been constrained by variability of production, perhaps due to poor survival and growth of early craylings. Diet contributes to survival and growth and previous studies have determined requirements for larger redclaw, but little research exists for the early craylings. An experiment was performed to evaluate survival and growth of early instar redclaw using four diets; Frippak (commercial shrimp diet), CSIRO compound diet, bloodworms, and on-grown Artemia. Bloodworms and Artemia produced significantly higher survival of craylings over two weeks than the two other diets. Artemia diet had a significantly higher weight increase than bloodworms or the CSIRO diet, but not Frippak, which did not differ from bloodworms or CSIRO. Biomass was significantly higher when fed Artemia. High mortality in the Frippak and CSIRO diet treatments were not wholly attributable to nutritional deficiencies as the manufactured diets became less physically accessible, potentially reducing intake, leading to difficulties completing ecdysis and eventually death. This study concluded that Artemia and bloodworms promoted highest survival, and Artemia and Frippak the highest weight gain. The best combination of survival, weight gain and biomass was with the Artemia diet
Morphology and weight-length relationships for the first six instars of Cherax quadricarinatus (von Martens, 1868)
Cherax quadricarinatus (redclaw) aquaculture has not achieved the industry growth that had been predicted in the early days of development. Provision of quality juvenile crayfish seed stock has been identified as a critical factor in overcoming industry development inertia. Hatchery technology has been developed to produce independent craylings and a nursery phase is now being developed to nurture the delicate craylings to a more advanced and robust juvenile stage, suitable for pond stocking. As part of the nursery development, clear definitions of the successive stages from egg through the first several instars, are required. Although some morphological descriptions of the early stages of redclaw have been made, the characteristics and nomenclature for stages from egg through to an advanced juvenile need clarification. A naming system is proposed (Egg, L1, L2, J1, J2 and J3) for the first six instars from egg, based on gross morphology and allometric relationships. Egg volume, wet weight and ocular carapace length (OCL) were analysed through linear regression. Based on these variables, the size of each instar is defined. Descriptions and photographs of the six instars provide a visual reference for identification. Five of the six instars had a significant relationship between wet weight and OCL. Both significantly increased for each successive instar. Lyophilized (dry) weight was not significantly different between stages until after instar J1, where endogenous feeding begins. The growth of the first four instars, in terms of wet weight and OCL but not dry weight, suggests an extra endogenous source of nutrition in addition to the yolk supply. Branchial water uptake during ecdysis has been proposed as a route for dissolved organic matter or small particulate matter to be acquired by the crayfish during the lecithotrophic, non-exogenous feeding stages, as an additional food source that might further enhance growth and survival
Diversion of Benzodiazepines through Healthcare Sources
Background—Benzodiazepines (BZ) are often diverted from legal sources to illicit markets at various points in the distribution process which begins with a pharmaceutical manufacturer, followed by distribution to healthcare providers, and finally, to the intended users. Little is known about the extent of BZ diversion involving distribution points directly related to healthcare sources (e.g., a script doctor) as opposed to points further down the distribution chain (e.g., street dealers). The present study examines the scope of BZ diversion via mechanisms directly related to a healthcare source. It examines the association between BZ dependence and the direct utilization of particular healthcare-related diversion sources among a diverse sample of prescription drug abusers in South Florida.
Method—Cross-sectional data were collected from five different groups of drug users: methadone-maintenance clients (n = 247), street drug users (n = 238), public-pay treatment clients (n = 246), private-pay treatment clients (n = 228), and stimulant using men who have sex with men (MSM; n = 248).
Results—Findings suggest that those ages 26 to 35 years old, non-Hispanic White participants, private-pay treatment clients, those who are insured, and those with higher incomes had higher odds of utilizing healthcare diversion sources. Participants utilized a pharmacy as a diversion source more than other healthcare sources of diversion, and the highest number of BZs were obtained from doctor shopping compared to other diversion sources. Those who reported BZ dependence also had 2.5 times greater odds of using a healthcare source to obtain BZs than those who did not meet criteria for dependence.
Discussion—Prevention of BZ diversion through healthcare sources should include strategies to reduce doctor shopping and diversion from pharmacies
Excited Hydroxyl Outflow in the High-Mass Star-Forming Region G34.26+0.15
G34.26+0.15 is a region of high-mass star formation that contains a broad
range of young stellar objects in different stages of evolution, including a
hot molecular core, hyper-compact HII regions and a prototypical cometary
ultra-compact HII region. Previous high-sensitivity single dish observations by
our group resulted in the detection of broad 6035 MHz OH absorption in this
region; the line showed a significant blue-shifted asymmetry indicative of
molecular gas expansion. We present high-sensitivity Karl G. Jansky Very Large
Array (VLA) observations of the 6035 MHz OH line conducted to image the
absorption and investigate its origin with respect to the different star
formation sites in the region. In addition, we report detection of 6030 MHz OH
absorption with the VLA and further observations of 4.7 GHz and 6.0 GHz OH
lines obtained with the Arecibo Telescope. The 6030 MHz OH line shows a very
similar absorption profile as the 6035 MHz OH line. We found that the 6035 MHz
OH line absorption region is spatially unresolved at " scales, and it
is coincident with one of the bright ionized cores of the cometary HII region
that shows broad radio recombination line emission. We discuss a scenario where
the OH absorption is tracing the remnants of a pole-on molecular outflow that
is being ionized inside-out by the ultra-compact HII region.Comment: 19 pages, 6 figures. Accepted for publication in The Astrophysical
Journa
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