377 research outputs found
Responding to Crises in the Public Schools: A Survey of School Psychologists\u27 Experiences and Perceptions
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
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
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
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
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
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
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
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
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
Stent insertion for incurable oesophageal carcinoma: what is the optimal treatment? - authors' reply
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