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Introduction: The optimal diagnostic strategy for children presenting to the Emergency Department (ED) with suspected appendicitis (SA), the most common non-traumatic surgical emergency in children, remains unclear. This study aims to identify which investigations and management priorities are preferred by Canadian surgeons prior to consultation from the ED. Methods: An internet survey was extended to practicing surgeons who are members of the Canadian Association of Pediatric Surgeons and Canadian Association of General Surgeons. Three case-based scenarios evaluated surgeons expected ED investigations and management for SA with varying severity of disease (simple - SA vs perforated - PA) and sex (male vs female). Differences across scenarios were determined by ANOVA and direct comparisons were reported using proportions and odds ratios with 95% confidence intervals. Results: Surveys were completed by 82 surgeons. Across the 3 cases, CBC (227/246, 92.3%) and urinalysis (188/246, 76.4%) were the sole investigations expected in >75% of responses. Expectations differed across cases for use of blood cultures (p<0.001), electrolytes (p<0.001), sexually transmitted infection testing (0.015) and ultrasound (US) (p<0.001). Blood cultures (26/82, 31.7% vs 4/82, 4.9%; OR 9.05 95%CI 2.88-37.33) and electrolytes (58/82, 70.7% vs 33/82, 40.2%; OR 3.59 95%CI 1.79-7.24) were expected more often in severe disease. US was expected more often in females (58/82,70.7% vs 25/82, 30.5%; OR 5.51, 95% CI 2.68-11.38). Expected management differed across cases for fluid boluses (p=0.01), intravenous (IV) analgesia (p<0.001) and antibiotics (p<0.001), with all differences attributed to severity of illness (fluids 73/82, 89.0% vs 59/82, 72.0% OR 3.16 95%CI 1.28-8.33; IV analgesia 66/82, 80.5% vs 42/82, 51.2% OR 3.93 95%CI 1.86-8.45; antibiotics 44/82, 53.7% vs 10/82, 12.2% OR 8.34 95%CI 3.59-20.44). Conclusion: Severity of illness and sex of the child impact the ED investigations and management expected by surgeons consulted for suspected appendicitis. Further research focusing on how these expectations influence patient outcomes should be conducted. Collaborative ED-surgery protocols for the diagnosis and management of acute appendicitis in children should be established.
Biodiversity conservation outside protected areas requires cooperation from affected communities, hence the extensive discussions of trade-offs in conservation, and of a so-called new conservation that addresses human relations with nature more fully. Human–wildlife conflict is one aspect of those relations, and as land use intensifies around protected areas the need to understand and manage its effects will only increase. Research on human–wildlife conflict often focuses on individual species but given that protecting wildlife requires protecting habitat, assessments of human–wildlife conflict should include subsidiary impacts that are associated with ecosystem conditions. Using a case study from Laikipia, Kenya, where conservation outside protected areas is critical, we analysed human–wildlife conflict from a household perspective, exploring the full range of impacts experienced by community members on Makurian Group Ranch. We addressed questions about four themes: (1) the relationship between experienced and reported human–wildlife conflict; (2) the results of a high-resolution assessment of experienced human–wildlife conflict; (3) the relative impact of high-frequency, low-severity conflict vs high-severity, low-frequency conflict; and (4) the effect of experienced conflict on receptivity to the conservation narrative. Our results show that high-frequency, low-severity conflict, which is often absent from reports and discussion in the literature, is a significant factor in shaping a community's perception of the cost–benefit ratio of conservation. Local, ongoing, high-resolution monitoring of human–wildlife conflict may facilitate more realistic and effective incorporation of the experienced impacts of human–wildlife conflict in conservation planning and management. Such monitoring could help to define locally appropriate trade-offs in conservation and thereby improve conservation outcomes.
Cryogenic detectors for gravitational wave astronomy promise greatly improved sensitivity over room temperature detectors. The 3 mK detector which we have under construction should give an improvement of 106 over existing detectors. The cryogenic antennae are described and the calculated low temperature performance is detailed. New superconducting instrumentation is described.
Experimental measurements of the intensity of the submillimeter background are reviewed. The latest results all indicate a low background; it is not yet possible to say whether or not the spectrum in this range is blackbody.
A four-man party representing the Arctic Institute of North America and the Department of Geology, Dartmouth College, went to the Ward Hunt Ice Shelf in 1960 to obtain ice cores for subsequent laboratory analysis. The overall objective of the project was to study the structural and stratigraphic history of the shelf and its relationship to the environment through laboratory analysis of the cores, using stratigraphic. petrologic, chemical, and physical methods.
The four cores obtained were logged, packed, and shipped to Dartmouth College for detailed study. The stratigraphy and structure of the ice were studied under natural and plane polarized light conditions. The results of this initial work showed that the cores were composed of four ice types: glacier ice, lake ice, sea ice, and transition ice. Chlorinity, sulfate, and density profiles complemented megascopic studies and were most useful criteria for plotting stratigraphie changes in ice type.
Results of the investigations thus far have yielded new information about the gross structure and stratigraphy of the ice shelf and re-entrant. They have also shown that the physical and chemical techniques employed will be useful in future ice-core analysis.
We observed the Planetary Nebula NGC 6720 with the Gemini Telescope and the Gemini Multi-Object Spectrographs. We obtained spatial maps of 36 emission-lines in the wavelength range between 3600 Å and 9400 Å. We derived maps of c(Hβ), electronic densities, electronic temperatures, ionic and elemental abundances, and Ionization Correction Factors (ICFs) in the source and investigated the mass-loss history of the progenitor. The elemental abundance results indicate the need for ICFs based on three-dimensional photoionization models.
The Southern Hemisphere VLBI Experiment (SHEVE) program is aimed at producing high-resolution images of southern radio sources. The radio telescopes of the present SHEVE array are described below and some recent results presented.
The objective of this study was to determine whether altered maternal energy supply during mid-gestation results in differences in muscle histology or genes regulating fetal adipose and muscle development. In total, 22 Angus cross-bred heifers (BW=527.73±8.3 kg) were assigned randomly to the three dietary treatments providing 146% (HIGH; n=7), 87% (INT; n=7) or 72% (LOW; n=8) of the energy requirements for heifers from day 85 to day 180 of gestation. Fetuses were removed via cesarean section at day 180 of gestation and longissimus muscle (LM) and subcutaneous fat were collected and prepared for analysis of gene expression. Samples from the LM and semitendinosus (ST) were evaluated for muscle fiber diameter, area and number. The right hind limb was dissected and analyzed to determine compositional analysis. Fetal growth and muscle histology characteristics of the LM and ST were similar among treatments. Preadipocyte factor-1 expression was up-regulated in fetal LM (P<0.05) of HIGH fetuses as compared with INT, whereas LOW fetuses showed increased CCAAT/enhancer-binding protein-β (C/EBP-β) expression in LM as compared with INT (P<0.05). Peroxisome proliferator-activated receptor γand C/EBP-α did not differ as a result of dietary treatment in LM or subcutaneous fat samples. There was a tendency for increased expression of fatty acid synthase in LM of LOW fetuses as compared with INT (P<0.10). Myogenin was more highly expressed (P<0.05) in LM of the LOW fetuses, whereas μ-calpain expression was increased in the HIGH treatment compared with INT. A tendency for increased expression of IGF-II was observed for both LOW and HIGH fetuses compared with INT (P<0.10). Expression of stearoyl-CoA desaturase, myoblast determination protein 1, myogenic factor 5, myogenic regulatory factor-4, m-calpain, calpastatin, IGF-I and myostatin was similar between treatments. Collectively, these results suggest that fetal growth characteristics are not affected by the level of maternal nutritional manipulation imposed in this study during mid-gestation. However, differences in expression of fetal genes regulating adipose and muscle tissue growth and development could lead to differences in postnatal composition and warrants further investigation.
Proxima Centauri was observed photoelectrically in the period July-September 1987 with a newly-installed computer-interfaced photometer. Four definite flares and six further possible events were recorded. The level of Proxima’s flaring activity was examined and no significant change since 1969 found.
The Perth Astronomy Research Group (PARG), consisting of members from Curtin University of Technology, Perth Observatory and the University of Western Australia, is in the process of developing an automated supernova search system, using the 61-cm Lowell-Perth reflector, a CCD camera and an 80386-based computer for image analysis. Computer control of the telescope and dome, a liquid-nitrogen-cooled CCD camera, and modified VISTA image analysis software will be completed in late 1990, allowing initial semi-automatic searching of external galaxies, together with CCD photometry of flare stars and newly discovered supernovae. Full-scale automation will be introduced subsequently, in collaboration with the Berkeley group. This paper describes the project, and reports on its current status.
It is shown that real-time FFT techniques used in conjunction with a small telescope can yield useful sensitivity. The suitability of the Crab pulsar as a calibrator is assessed. The mains frequency modulation in the night sky above Perth is clearly discerned, with several harmonics. Detectable signal modulation limits for SN 1987A are derived as a function of frequency in the range 10-2000 Hz.
Both physical activity (PA) and diet are important contributors to health and well-being; however, there is limited information on the association of these behaviours and whether observed associations differ by weight. The present study aimed to evaluate whether nutrient intake is associated with PA and if this association varies by weight in young adults.
Cross-sectional study to analyse the association between PA and nutrient intake.
Participants were stratified as normal weight (18·5 kg/m2 <BMI <25·0 kg/m2) and overweight/obese (BMI≥25·0 kg/m2). PA level (PAL) was calculated (PAL=total daily energy expenditure/RMR) and used to stratify groups (PAL<1·6, 1·6≤PAL<1·9, PAL≥1·9).
Adults (n 407; age 27·6 (sd 3·8) years, 48 % male), with BMI between 20 and 35 kg/m2, having at least two 24 h diet recalls and at least 5 d (including two weekend days) of valid, objectively measured PA data were included in the analysis.
In normal-weight participants, higher PAL was associated with higher intakes of minerals (except Ca, Fe and Zn), B-vitamins and choline (P for trend <0·05). In the overweight/obese group, higher PAL was associated with higher intakes of fibre, K, Na and Cu (P for trend <0·05). These differences, however, were no longer significant after additionally controlling for total energy intake.
More active young adults have higher intakes of essential micronutrients. The benefits of PA may be predominantly due to a higher overall food intake while maintaining energy balance rather than a healthier diet.
Increasing evidence shows attachment security influences symptom expression and adaptation in people diagnosed with schizophrenia and other psychoses.
To describe the distribution of secure and insecure attachment in a cohort of individuals with first-episode psychosis, and to explore the relationship between attachment security and recovery from positive and negative symptoms in the first 12 months.
The study was a prospective 12-month cohort study. The role of attachment, duration of untreated psychosis (DUP), baseline symptoms and insight in predicting and mediating recovery from symptoms was investigated using multiple regression analysis and path analysis.
Of the 79 participants, 54 completed the Adult Attachment Interview (AAI): 37 (68.5%) were classified as insecure, of which 26 (48.1%) were insecure/dismissing and 11 (20.4%) insecure preoccupied. Both DUP and insight predicted recovery from positive symptoms at 12 months. Attachment security, DUP and insight predicted recovery from negative symptoms at 12 months.
Attachment is an important construct contributing to understanding and development of interventions promoting recovery following first-episode psychosis.
This chapter reviews evidence concerning the vital role that temporal dynamics can have in the ecology of trees and other long-lived species in the assembly and maintenance of natural communities. The research synthesised here was stimulated by a desire to determine the action of temporal dynamics in nature, and its implications for the nature of competition, community structure and assembly on multiple scales and across a range of climatic conditions. For the most part, the results discussed concern tropical forests, but we think they provide strong support for a more general view that can be applied across biomes. Finally, we ask if there may be a potential role for temporal dynamics in speciation, in light of what we have learned from the tropical trees.
A field programme begun in the late ’90s in the tropical dry forest of México was consciously designed to study the coexistence of closely related species in a very speciose community, but the role of temporal dynamics had not been suspected and its finding was serendipitous. With centuries-long lifespans, decades-long juvenile stages and low population turnover rates, trees are problematic candidates for demographic analyses, either observational or experimental. Unless instant death is involved, the particular hurdle with trees, as with any long-lived organism, is directly connecting any specific response in the early life of the individual with the long-term individual persistence or character of the standing population. However, trees differ from many long-lived organisms in carrying their history in their structure at both the individual and population levels. Thus, a tree population itself documents individual success over the history of the population (Parker et al. 1997, Cole et al. 2011). The distribution of a population with regard to physical conditions, size and age structure and relative to other woody species all contain information on the ecology and interactions of species (e.g. Veblen 1989, 1992, Villalba and Veblen 1998, Kelly et al. 2001) and it was the age structure of populations that revealed the action of temporal dynamics at Chamela Biological Station.
An enormous effort is underway worldwide to attempt to detect gravitational waves. If successful, this will open a new frontier in astronomy. An essential portion of this effort is being carried out in Australia by the Australian Consortium for Interferometric Gravitational Astronomy (ACIGA), with research teams working at the Australia National University, University of Western Australia, and University of Adelaide involving scientists and students representing many more institutions and nations. ACIGA is developing ultrastable high-power continuous-wave lasers for the next generation interferometric gravity wave detectors; researching the problems associated with high optical power in resonant cavities; opening frontiers in advanced interferometry configurations, quantum optics, and signal extraction; and is the world's leader in high-performance vibration isolation and suspension design. ACIGA has also been active in theoretical research and modelling of potential astronomical gravitational wave sources, and in developing data analysis detection algorithms. ACIGA has opened a research facility north of Perth, Western Australia, which will be the culmination of these efforts. This paper briefly reviews ACIGA's research activities and the prospects for gravitational wave astronomy in the southern hemisphere.
The new 1 m f/4 fast-slew Zadko Telescope was installed in June 2008 about 70 km north of Perth, Western Australia. It is the only metre-class optical facility at this southern latitude between the east coast of Australia and South Africa, and can rapidly image optical transients at a longitude not monitored by other similar facilities. We report on first imaging tests of a pilot program of minor planet searches, and Target of Opportunity observations triggered by the Swift satellite. In 12 months, 6 gamma-ray burst afterglows were detected, with estimated magnitudes; two of them, GRB 090205 (z = 4.65) and GRB 090516 (z = 4.11), are among the most distant optical transients imaged by an Australian telescope. Many asteroids were observed in a systematic 3-month search. In September 2009, an automatic telescope control system was installed, which will be used to link the facility to a global robotic telescope network; future targets will include fast optical transients triggered by high-energy satellites, radio transient detections, and LIGO gravitational wave candidate events. We also outline the importance of the facility as a potential tool for education, training, and public outreach.
This article advocates for a comparative approach to archaeological studies of colonialism that considers how Native American societies with divergent political economies may have influenced various kinds of processes and outcomes in their encounters with European colonists. Three dimensions of indigenous political economies (polity size, polity structure, and landscape management practices) are identified as critical variables in colonial research. The importance of considering these dimensions is exemplified in a case study from California, which shows how small-sized polities, weak to moderate political hierarchies, and regionally oriented pyrodiversity economies played significant roles in the kinds of colonial relationships that unfolded. The case study illustrates how the colonial experiences of Native Californians differed from those of other tribal groups that confronted similar kinds of colonial programs involving Franciscan missionaries elsewhere in North America. The article stresses that the archaeology of colonialism is not simply an arcane academic exercise but, rather, has real-life relevancy for people who remain haunted by the legacies of colonialism, such as those petitioning for federal recognition in California.