377 research outputs found

    Responding to Crises in the Public Schools: A Survey of School Psychologists\u27 Experiences and Perceptions

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    A survey was created and mailed to 500 school psychologists randomly selected from the National Association of School Psychologists\u27 membership lists. The final sample consisted of 228 school psychologists working at least half-time in a school setting. The survey\u27s purpose was to gather information from school psychologists on their perspectives on crisis training and on crises experienced by public schools, as well as what schools have for crisis plans/teams, and what they do for crisis response. Nearly all of the participants (98.2%) reported that they had some type of crisis intervention training. The majority of respondents indicated that their schools had both crisis plans (95.1%) and teams (83.6%). Most of the participants reported that their schqols have experienced and responded to serious crises. Respondents indicated that lll psychological debriefing was being used by the majority of schools (67%). Many participants suggested that additional training and practice would improve schools\u27 crisis responses

    Long-Range Hydrophobic Attraction Between Graphene and Water/Oil Interfaces

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    Long-range hydrophobic attractions between mesoscopic surfaces in water play an important role in many colloid and interface phenomena. Despite being studied by several approaches, the origin of these forces has yet to be adequately explained. While previous research has focused on solid/water/solid and solid/water/air scenarios, we investigated a solid/water/liquid situation to gain additional insight. We directly measured the long-range interactions between a solid and a hydrophobic liquid separated by water using force spectroscopy, where colloidal probes were coated with graphene oxide (GO) to interact with immobilized heptane droplets in water. We detected attractions with a range of ~0.5 {\mu}m that cannot be explained by standard Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. When the GO was reduced to rGO to become more hydrophobic, these forces increased in strength and ranged up to 1.2 {\mu}m. This suggests that the observed attractions result from long-range hydrophobic forces. Based on our results, we propose air bubbles attached to the colloidal probe and molecular rearrangement at the water/oil interface as possible origins of the observed interactions. This knowledge will be useful to understand and motivate the formation of emulsions using 2D materials and other amphiphilic/hydrophobic particles

    Enantiodromia : an exegesis presented in partial fulfilment of the requirements for the degree of Master of Fine Arts at Massey University, Wellington, New Zealand

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    This exegesis explores the trajectory of my artistic practice between 2020-2021. It begins with a prologue discussing a childhood memory that resurfaced on multiple occasions throughout my MFA. Two further areas of interest from my personal history – the concept of enantiodromia and the Zen Buddhist tenet of “nothingness” – are also offered as the main threads that run through my entire thesis project. I then discuss a group of drawings I brought with me into the MFA which became the visual foundation on which my current work was constructed. My art historical background from late Gothic through to Surrealism and other relevant artist models I discovered during the MFA such as Josef Albers and Donald Judd, work to contextualise my arts practice and anchor it in both historical artistic precedent and modern art theory. My methodology is centred around the notion of iteration, and I suggest my attempts at manipulation of the display environment I hang my paintings in is yet another step in the iterative journey of searching. This searching is then tied in with the repetition of the motif in my imagery. I also include a discussion of my intentions for the final display of my work at the end of the MFA and how it may be the final stage of the MFA but it is also a stepping off from this chapter and onto the next, suggesting further areas of development and exploration

    Novel approaches to the diagnostic and prognostic assessment of coronary heart disease

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    BACKGROUND Cardiovascular disease, principally manifest as myocardial infarction or stroke, is the dominant cause of death worldwide and despite therapeutic advances, the global burden of these conditions continues to increase. In order to address this ongoing disease burden, there is a clear need to more effectively target the use of existing and novel diagnostic investigations and medical therapies. Emerging cardiovascular biomarkers include the biochemical, such as high-sensitivity cardiac troponin, and the radiological, such as computed tomography coronary angiography (CTCA) and 18Ffluoride positron emission tomography (PET). Cardiac troponins can now be reliably quantified in clinically stable or asymptomatic populations and provide information about myocardial pathophysiology, whilst CTCA can non-invasively quantify atherosclerotic burden and 18F-fluoride PET imaging offers insight into plaque vulnerability. Improved targeting of diagnostic investigations requires more reliable estimation of pre-test probability of coronary disease whilst optimizing the use of pharmacological or interventional treatments requires more accurate prognostic stratification. Achieving both objectives in an equitable manner across all population groups will depend upon updated clinical guidelines containing improved risk models and enhanced management pathways. The objective of this thesis was to investigate the potential clinical benefit of novel approaches to the diagnostic and prognostic assessment of coronary heart disease. EVALUATION OF THE 2016 NATIONAL INSTITUTE FOR HEALTH AND CARE EXCELLENCE (NICE) GUIDANCE ON THE ASSESSMENT OF SUSPECTED STABLE ANGINA. A post-hoc analysis was undertaken of the Scottish COmputed Tomography of the HEART (SCOT-HEART) trial of 4,146 participants with suspected angina randomised to assessment with computed tomography coronary angiography or standard care. Patients were dichotomised according to guideline definitions into groups representing possible angina and non-anginal presentations. The primary (diagnostic) endpoint was diagnostic certainty of angina at 6 weeks and the prognostic endpoint comprised fatal and non-fatal myocardial infarction. In 3,770 eligible participants, CTCA increased diagnostic certainty more in those with possible angina (relative risk [RR] 2.22 (95% CI 1.91-2.60), p<0.001) than those with non-anginal symptoms (RR 1.30 (1.11-1.53), p=0.002; pinteraction<0.001). In the possible angina cohort, CTCA did not change rates of invasive angiography (p=0.481) but markedly reduced rates of normal coronary angiography (hazard ratio [HR] 0.32 (0.19-0.52), p<0.001). In the non-anginal cohort, rates of invasive angiography increased (HR 1.82 (1.13-2.92), p=0.014) without reducing rates of normal coronary angiography (HR 0.78 (0.30-2.05), p=0.622). At 3.2 years of follow-up, fatal or nonfatal MI was reduced in patients with possible angina (3.2% to 1.9%; HR 0.58 (0.34- 0.99), p=0.045) but not in those with non-anginal symptoms (HR 0.65 (0.25-1.69), p=0.379). Overall the updated NICE guidance on patient assessment maximises the benefits of CTCA with respect to diagnostic certainty, the use of invasive coronary angiography, and reductions in fatal and non-fatal myocardial infarction. Patients with non-anginal chest pain derive minimal benefit from CTCA, which instead increases rates of invasive investigation. EXTERNAL VALIDATION OF THE PROSPECTIVE MULTICENTER IMAGING STUDY FOR EVALUATION OF CHEST PAIN (PROMISE) TOOL FOR DETERMINING MINIMAL-RISK OF CORONARY ARTERY DISEASE. The PROspective Multicenter Imaging Study for Evaluation of chest pain (PROMISE) minimal-risk tool was recently developed to identify patients with suspected stable angina at very low risk of coronary artery disease and clinical events. The external validity of this tool was investigated within the context of the Scottish Computed Tomography of the HEART multicenter randomised controlled trial of patients with suspected stable angina due to coronary artery disease. Model discrimination and calibration was determined amongst 1,764 patients in whom complete CCTA data were available and compared with the European Society of Cardiology guideline-endorsed Coronary Artery Disease Consortium (CADC) risk score. The PROMISE minimal-risk tool improved discrimination compared with the CADC model (c-statistic 0.785 vs 0.730, p<0.001) and was improved further following re-estimation of covariate coefficients (c-statistic 0.805, p<0.001). Model calibration was initially poor (c2 197.6, Hosmer-Lemeshow [HL] p<0.001), with significant overestimation of probability of minimal risk, but improved significantly following revision of the PROMISE minimal-risk intercept and covariate coefficients (c2 5.6, HL p=0.692). HIGH-SENSITIVITY CARDIAC TROPONIN I IN THE DIAGNOSIS OF STABLE CORONARY ARTERY DISEASE In a pre-specified sub-study of the Scottish COmputed Tomography of the Heart trial, plasma cardiac troponin was measured using a high-sensitivity single molecule counting assay in 943 adults with suspected stable angina who had undergone coronary computed tomography angiography. Rates of obstructive coronary artery disease were compared with the pre-test probability determined by the European Society of Cardiology Coronary Artery Disease Consortium risk model with and without cardiac troponin concentrations. External validation was undertaken in an independent study population from Denmark comprising 487 patients with suspected stable angina. Higher cardiac troponin concentrations were associated with obstructive coronary artery disease with a 5-fold increase across quintiles (9 to 48%, p<0.001) independent of known cardiovascular risk factors (odds ratio [OR] 1.35 [95% confidence interval (CI) 1.25-1.46] per doubling of troponin). Cardiac troponin concentrations improved the discrimination of the ESC model for identifying obstructive coronary artery disease (c-statistic 0.785 to 0.800, p=0.003) and improved classification into ESCrecommended categories of clinical risk (net reclassification improvement 0.143 [95% CI, 0.093-0.193]). The revised model achieved similar improvements in discrimination and net reclassification when applied in the external validation cohort. HIGH-SENSITIVITY CARDIAC TROPONIN I IN CARDIOVASCULAR RISK STRATIFICATION OF PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND HEIGHTENED CARDIOVASCULAR RISK. The association between plasma high-sensitivity cardiac troponin I concentration and cardiovascular events in patients with chronic obstructive pulmonary disease and heightened cardiovascular risk was examined within the context of a double-blind randomised controlled trial of inhaled corticosteroids and bronchodilators (1 placebo arm and 3 different treatment arms). Plasma cardiac troponin I concentrations were measured with a high-sensitivity assay in a subgroup of 1,599 patients. The cardiovascular endpoint was a composite of cardiovascular death, myocardial infarction, stroke, unstable angina and transient ischaemic attack during follow-up of 1.5 years. Baseline plasma cardiac troponin I concentrations were above the lower limit of detection (1.0 ng/L) in 1,559 (97.5%) patients and were unaffected by inhaled therapies at 3 months (p>0.05 for all). Compared with the lowest tertile (cardiac troponin I ≤3.0 ng/L), patients in the highest tertile (≥ 5.5 ng/L) were at greater risk of cardiovascular events (hazard ratio 3.0, 95% confidence interval 1.5 to 6.2, p=0.002) and cardiovascular death (hazard ratio 9.6, 95% confidence interval 2.6 to 35.6, p<0.001) after adjustment for cardiovascular risk factors. There were no differences in COPD exacerbations between tertiles even after adjustment (p>0.05). REPRODUCIBILITY OF CORONARY 18F-FLUORIDE PET-CT IMAGING The inter-observer and scan-rescan reproducibility of coronary 18F-fluoride PET-CT imaging was investigated in 20 patients with clinically stable but high risk multi-vessel coronary artery disease who underwent repeated 18F-fluoride PET-CT scans 11.5±4.5 days apart. Scan analysis using the currently accepted approach of normalisation to a referent coronary segment (TBRREFERENT) identified 10 (50%) patients with evidence of focal coronary 18F-fluoride uptake and demonstrated moderate agreement across observers on a per-patient level (k = 0.56). This was similar to the level of agreement achieved with visual assessment alone (k = 0.64). Reproducibility was improved by semi-quantitative reporting combining visual assessment with a threshold uptake value for determining the presence of tracer uptake (k = 0.84). Using the optimised approach achieved excellent agreement on overall segmental uptake counts (intra-class correlation = 0.97). CONCLUSION Cardiovascular diagnostic and prognostic assessments represent a complex endeavour and established tools for risk prediction can demonstrate suboptimal predictive accuracy when evaluated in patient cohorts that are independent of the population used for model derivation. The process of risk stratification has important potential for improvement through the integration of existing approaches with novel biochemical and non-invasive diagnostic imaging technologies that provide unique insights into structural and pathophysiological processes. The promise such developments hold requires rigorous assessment in well-designed trials involving patients who closely reflect the population most likely to receive treatment. Such trials are difficult and costly to conduct with traditional methods and careful consideration should be given to more pragmatic clinical trial designs

    Wire coating containing thermally exfoliated graphite oxide

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    A wire coating containing a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m.sup.2/g

    Automotive body panel containing thermally exfoliated graphite oxide

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    An automotive body panel containing a polymer composite formed of at least one polymer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m.sup.2/g to 2600 m.sup.2/g

    The role of palliative radiotherapy for haemostasis in unresectable gastric cancer:a single-institution experience

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    Purpose: To evaluate the outcomes of patients with gastric cancer bleeding who had been treated with palliative radiotherapy with haemostatic intent. Methods and materials: Fifty-two gastric cancer patients aged 52–92 years (median 78 years) with active bleeding or anaemia resulting from inoperable gastric cancer were treated with short-course radiotherapy. Responses to radiotherapy treatment were evaluated based on the changes of haemoglobin level, number of transfusions received before and after radiotherapy, and overall median survival. Results: Thirty-nine (75%) patients received single 8 Gy fraction, and 13 (25%) patients received 20 Gy in five daily fractions. The need for transfusion was evaluable in 44 patients, and the response rate was 50%, with less requirement for blood transfusions within four weeks of radiotherapy. There was also an increase in mean haemoglobin level (0.66 ± 1.12 g/dl, p < 0.01) after radiotherapy in 35 evaluable patients. The overall median survival (calculated from last day of treatment to date of death) was 160 days (95% CI of 119–201 days), making actuarial 12-month survival 15%. Conclusion: Palliative short-course radiotherapy is a reasonably effective treatment that can provide durable palliation of bleeding in gastric cancer. Keywords: bleeding, gastric cancer, haemostasis, palliative, radiotherap

    High-temperature oxidation and ignition of metals

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    A study of the high-temperature oxidation of several aircraft construction materials was undertaken to assess the possibility of ignition under high-temperature flight conditions.Tests have been made both in open and closed jets, and, in addition, the burning of metals has been observed under static conditions in a pressurized vessel containing either air, oxygen, or nitrogen. When heated in an atmosphere of oxygen or when heated and plunged into a supersonic airstream, titanium, iron, carbon steel, and common alloys such as 4130 were found to have spontaneous-ignition temperatures in the solid phase (below melting) and they melted rapidly while burning. Inconel, copper, 18-8 stainless steel, Monel, and aluminum could not be made to ignite spontaneously at temperatures up to melting with the equipment available. Magnesium ignited spontaneously in either type of test at temperatures just above the melting temperature.A theory for the spontaneous ignition of metals, based on the first law of thermodynamics, is presented. Good correlation was obtained between calculated spontaneous-ignition temperatures and values measured in supersonic jet tests. There appears at the present time to be no need for concern regarding the spontaneous ignition of Inconel, the stainless steels, copper, aluminum, or magnesium for ordinary supersonic airplane or missile applications where the material temperature is kept within ordinary structural limits or at least below melting. For hypersonic applications where the material is to be melted away to absorb the heat of convection, the results of the present tests do not apply sufficiently to allow a conclusion

    Polymerization method for formation of thermally exfoliated graphite oxide containing polymer

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    A process for polymerization of at least one monomer including polymerizing the at least one monomer in the presence of a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m(esp 2)/g to 2600 m(esp 2/g
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