32,269 research outputs found

    Fishes of the King Edward and Carson Rivers with their Belaa and Ngarinyin names

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    During two separate sampling trips, in October to November 2004 and in June to July 2005, 42 sites on the King Edward River and Carson River and their tributaries were sampled for fish. Fish were captured using fine mesh seine nets and gill nets and were observed using mask and snorkel and from visual surveys. The results of this study have revealed that the number of freshwater fishes (species diversity) of the King Edward River is higher than has previously been recorded for a Western Australian river. Twenty-six freshwater fish species were recorded, which is three species higher than the much larger Fitzroy River in the southern Kimberley. The study also resulted in a number of range extensions, including Butler’s Grunter and Silver Cobbler to the west, and the Slender Gudgeon to the north and east. What appears to be an undescribed species of glassfish was captured. It differs morphologically from described species in head spines (or lack of), fin rays, as well as relative body measurements. Similarly, an undescribed ectoparasite, Argulus sp. (Crustacea: Branchiura), was found on the caudal (tail) fin lobes of one Black Bream (Jenkin’s Grunter) and three Spangled Perch. Interestingly, a considerable proportion of Black Bream, which is widespread throughout the system but essentially restricted to main channel sites, had ‘blubber-lips’. There were significant differences in the prevailing fish fauna of the different reaches of the King Edward River system. Thus fish associations in the upper King Edward River main channel were significantly different to those in the tributaries and the main channel of the Carson River. Similarly, the fauna of the Carson River, which was much more diverse than the King Edward River main channel and tributary sites, was characterised by many species that were not found in other parts of the river. The presence of barriers, in the form of waterfalls which do not permit upstream migrations of fishes are considered to be the main factor in limiting the distribution of many species. For example, many species are restricted to the lower sections of the Carson River, and include Bony Bream, Lesser Salmon Catfish, Silver Cobbler, Black Catfish, False-spined Catfish, Freshwater Longtom, Prince Regent Hardyhead, Mouth Almighty, Barred Grunter and Butler’s Grunter. It is hypothesised that these natural barriers were in place long before many of these latter species colonised the King Edward River. Some species tend to only be found within tributary sites, e.g. Kimberley Mogurnda, while others are most abundant in tributaries rather than main channel sites, e.g. Western Rainbowfish and Spangled Perch. Waterfalls are also seen as limiting the number of migratory marine/estuarine species that enter freshwaters. For example, only three species that require the marine/estuarine environment to complete their life-cycle (i.e. salt water) were captured in the freshwaters of the King Edward River system. This compares to 14 species that utilise the freshwaters of the Fitzroy River

    Simultaneous polymerization and molding of Pyrrone polymers

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    Simultaneous polymerization and hot pressing of Pyrrone polymer

    Thermal contraints on high-pressure granulite metamorphism of supracrustal rocks

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    The circumstances leading to the formation and exposure at the Earth's surface of supracrustal granulites are examined. These are defined as sediments, volcanics, and other rock units which originally formed at the surface of the Earth, were metamorphosed to high-pressure granulite facies (T = 700-900 C, P = 5-10 kbar), and reexposed at the Earth's surface, in many cases underlain by normal thicknesses of continental crust (30-40 km). Five possible heating mechanisms to account for granulite metamorphism of supracrustal rocks are discussed: magnetic heating, thermal relaxation of perturbed temperature profiles following underthrusting of the continental crust, thermal relaxation after underthrusting of thin slivers of supracrustal rocks below continental crust of normal thickness, major preheating of the upper plate, and shear heating caused by frictional stress along the thrust plane

    Large-scale educational telecommunications systems for the US: An analysis of educational needs and technological opportunities

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    The needs to be served, the subsectors in which the system might be used, the technology employed, and the prospects for future utilization of an educational telecommunications delivery system are described and analyzed. Educational subsectors are analyzed with emphasis on the current status and trends within each subsector. Issues which affect future development, and prospects for future use of media, technology, and large-scale electronic delivery within each subsector are included. Information on technology utilization is presented. Educational telecommunications services are identified and grouped into categories: public television and radio, instructional television, computer aided instruction, computer resource sharing, and information resource sharing. Technology based services, their current utilization, and factors which affect future development are stressed. The role of communications satellites in providing these services is discussed. Efforts to analyze and estimate future utilization of large-scale educational telecommunications are summarized. Factors which affect future utilization are identified. Conclusions are presented

    Toward Prescriptive Alternatives to Secondary School Suspensions: Risk Analysis Using an Epidemiologic Approach.

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    Data were collected from a large urban high school in order to investigate the characteristics of students who get suspended. Descriptive, epidemiologic analyses, and multivariate statistical analyses were used to investigate which, if any of several screening variables were most likely to predict secondary school suspensions for 9th grade students. Because multivariate statistics may be tedious for many to interpret, epidemiologic analyses were used in order to more easily disseminate study findings to readers and those within the school setting. For males, statistics were calculated for three groups of students: (1) males having more than one 9th grade suspension, (2) males having any 9th grade suspensions, and (3) males having no 9th grade suspensions. For females, statistics were calculated for two groups of students: (1) females having any 9th grade suspensions, and (2) females having no 9th grade suspensions. Overall, students having at least one suspension during their 8th grade year were found to be at greater risk for suspension during the 9th grade. Analyses conducted across gender indicated that males were over three times more likely to be suspended than females. Also, the variables associated with an increase in the likelihood of suspension for males and females were different. More specifically, for males having any 9th grade suspensions, a GPA of 1.60 or lower, any suspensions during the 8th grade, a significant score on the SSRS, and any significant score on subscales of the Youth Self-Report (YSR) were associated with an increase in the likelihood of suspension. Importantly, analyses also indicated that males with more than one suspension were found to have a greater incidence of reading deficits and absences during the 8th grade than males with only one or no suspensions. For females, suspensions during the 8th grade, a significant score on any subscale of the Child Behavior Checklist (CBCL), absences during the 8th grade, significant scores on subscales of the Youth Self-Report (YSR), and a significant score on the Reynolds Adolescent Depression Scale (RADS) were associated with an increase in the likelihood of 9th grade suspension
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