Locus of control modification as a function of siituational control and performance feedback : a replication and extension

Fifty-four middle school age (sixth to eighth grade) children took part in a study designed to examine the effects of situational control and performance feedback on locus of control orientation. The subjects took part in a task situation in which they were asked to read three fictitious experiments and decide from a list of ten results which ones were actually found in the experiment and which were not. Pre and post-task measures were obtained on two locus of control scales. The Locus of Control Scale For Success - Failure (Epstein and Komorita, 1971) was answered in direct relation to the task situation and provided a task specific measure of control orientation. The pre-task measure on this scale was obtained by giving the subjects a sample of the task to examine prior to the experimental manipulations. The Intellectual Achievement Responsibility Questionnaire (IAR) (Crandall, et. al., 1965) was used to obtain the subjects\u27 control orientation for the academic achievement situation. The pre-testing was done in large groups and took place at least two weeks prior to the individual task situation and post-testing. Subjects were randomly assigned to one of three instruction groups: skill (personal control) oriented, chance (no personal control) oriented, or no control orientation. Subjects were also randomly assigned to one of three feedback (falsified) groups: success, failure, or no feedback. This design yielded nine treatment groups with six subjects in each group. The hypotheses tested were (a) The experience of personal control (skill instructions) would lead to greater internal control orientation, while the experience of no personal control (chance instructions) would result in greater external control orientation. (b) Success feedback would bring about a shift toward a more internal control orientation and failure feedback would result in a greater external control orientation. The no control orientation instructions and the no feedback factors were used as controls on type of instructions and type of feedback, respectively, and were not expected to lead to any differential shifting in control orientation. No interaction effects were predicted. The test data were analyzed in a 3 X 3 X 2, mixed effects analysis of variance, with repeated measures on the pre and post task locus of control score factor. Separate analyses were performed on the Locus of Control Scale for Success-Failure and on the r+ subscale, r- subscale, and total I score of the TAR. The results did not support the first hypothesis. Personal control versus no personal control, as manipulated by skill-chance instructions had no significant effects on locus of control scores. The results supported the second hypothesis fairly clearly with the Locus of Control Scale for SuccessFailure but not at all with the IAR. A significant trials X feedback interreaction with the Locus of Control Scale for Success - Failure scores was broken down and indicated that: (a) The failure and success groups changed differentially. (b) The failure and no feedback groups changed differentially. (c) The failure group changed significantly in a more external direction. (d) The failure group was significantly more external than the success group on the post-test, while there were no significant differences among the three feedback groups on the pre-test. The only significant finding with the IAR was an overall shift towards greater internality on the r- subscale and the total I score. Results were discussed in terms of the generalization and multidimensionality of the locus of control concept

Nondestructive Evaluation of Changes in Mechanical Properties in Carbon-Carbon Composites During Processing

In the next decade, there will be a concerted effort to develop hypersonic aircraft for commercial applications. It is anticipated that the design of these vehicles will place new demands on material performance at elevated temperatures. Temperatures in excess of 3200° F will be experienced at hypersonic speeds in certain critical areas of the structure, such as the tip of the nose and the wing leading edges. Carbon-carbon composites are one of the few structural materials available which retain a significant fraction of their specific stiffness and strength at elevated temperatures. Consequently, there is a great deal of interest in carbon-carbon composites as structural materials for hypersonic applications. While this material offers much promise for the future, many problems remain to be solved before it can be effectively utilized

Transthoracic repair of innominate and common carotid artery disease: Immediate and long-term outcome for 100 consecutive surgical reconstructions

AbstractPurpose: This is a review of 100 consecutive supraaortic trunk reconstructions (SAT) performed over 16 years. Methods: There were eight innominate endarterectomies and 92 bypass procedures based on the thoracic aorta (n = 86) or proximal innominate artery (n = 6) in 98 patients 24 to 79 years of age. Indications included cerebrovascular ischemia in 83 and upper extremity ischemia in four. Thirteen patients were asymptomatic. An innominate lesion was bypassed in 78 cases. The left common carotid and left subclavian arteries required reconstruction in 38 and nine patients, respectively. Multiple trunks were reconstructed by direct bypass grafting in 35. Approach was via median sternotomy in 92, partial sternotomy in six, and left thoracotomy in two. Seven patients underwent concomitant cardiac surgery. Results: Eight deaths and eight nonfatal strokes occurred, for a combined stroke/death rate of 16%. The operative mortality rate was 6% for SAT and 29% for SAT/cardiac operations. Perioperative complications included two asymptomatic graft occlusions, three nonfatal myocardial infarctions, seven significant pulmonary complications, three sternal wound infections, and one recurrent laryngeal nerve injury. Follow-up ranged from 1 to 184 months (mean, 51 ± 4.8 months). Eight patients were lost to follow-up. Twenty-one late deaths occurred. Two SATs required late revision. The cumulative primary patency rates at 5 and 10 years were 94% ± 3% and 88% ± 6%, respectively. The stroke-free survival rates at 5 and 10 years were 87% ± 4% and 81% ± 7%, respectively. Patients who survived beyond 30 days had a median stroke-free life expectancy of 10 years, 7 months (SE, 6%). Conclusions: Direct reconstruction of complex symptomatic SAT lesions can be performed with acceptable death/stroke rates and with long-term patient benefit. Asymptomatic lesions in patients who have significant concomitant conditions should be managed with a less-morbid cervical or endovascular approach, even if long-term outcome of the latter is inferior. (J Vasc Surg 1998;27:34-42.

Mühendislikte etik: afet etiği ve ötesi

Fracture Professional engineering societies and colleges of engineering are increasingly recognizing that they should take new steps to educate engineers in the ethics and social implications of their work. From my own experience and my preference for STS methods, I think STS scholars are well positioned to bring their knowledge and research skills to bear on such a vital subject. By providing a more in-depth picture of engineering practice and its wider ties with politics, economics, and other occupations, STS scholars can complement the traditional approach by moral philosophy and practicing engineers. Although engineering accidents have historically played a role in improving the design of artifacts (Petroski, 1985) and have a conspicuous presence in the current pedagogy of engineering ethics, I think the STS approach helps us move beyond "disaster ethics." By using STS analytical tools, including Vaughan's study of an accident, we can bring the everyday practice of engineering into classrooms to enrich the teaching of engineering ethics. Studyingon some projects, more so than spectacular accidents, may be more persuasive in convincing engineering students and academic colleagues alike that they need better methods in how to deal with every day issues of tremendous significance regarding the ethical and social implications of engineering. Keywords: Ethics, engineering ethics, disaster ethics.Mühendislik üretimlerinden kaynaklanan işlerin tasarım, yapım, denetim hataları günlük yaşamda kazalara yol açabiliyor veya deprem benzeri ciddi büyük ölçekli afetler sonucunda onarılamaz yıkımlar yaratabiliyor. Mühendislik mesleğindeki etik ve eğitim sorunları, sosyal yaşamda meydana gelen kazalar ve deprem gibi afetler söz konusu olduğunda çok önem kazanıyor. Bu nedenle mühendisliğe yönelik etik eğitiminin geliştirilmesi kaçınılmazdır. Geleneksel etik felsefesi ve mühendislik pratiğinin buluştuğu bir eğitim yönteminin geliştirilmesi ve afet etiğinin ötesine geçilmesini kolaylaştıracaktır. Bu yazı, böyle bir eğitim yönteminin neden gerekli olduğu nasıl geliştirilebileceği ve önemini ele almakta; dahası mühendislik hatalarının sosyal yaşamda yarattığı kaza ve afetler örneklendirilmektedir. Anahtar Kelimeler: Etik, mühendislik etiği, afet etiği

Behavioral and anatomical characterization of the bilateral sciatic nerve chronic constriction (bCCI) injury: correlation of anatomic changes and responses to cold stimuli

<p>Abstract</p> <p>Background</p> <p>Unilateral constrictive sciatic nerve injury (uCCI) is a common neuropathic pain model. However, the bilateral constrictive injury (bCCI) model is less well studied, and shows unique characteristics. In the present study, we sought to correlate effects of bCCI on nocifensive responses to cold and mechanical stimuli with selected dorsal horn anatomic markers. bCCI or sham ligation of both rat sciatic nerves were followed up to 90 days of behavioural testing. Additional rats sacrificed at 15, 30 and 90 days were used for anatomic analyses. Behavioural tests included hindpaw withdrawal responses to topical acetone, cold plate testing, an operant thermal preference task and hindpaw withdrawal thresholds to mechanical probing.</p> <p>Results</p> <p>All nocifensive responses to cold increased and remained enhanced for >45 days. Mechanical withdrawal thresholds decreased for 25 days only. Densitometric analyses of immunoperoxidase staining in the superficial dorsal horn at L4-5 revealed decreased cholecystokinin (CCK) staining at all times after bCCI, decreased mu opiate receptor (MOR) staining, maximal at 15 days, increased neuropeptide Y (NPY) staining only at days 15 and 30, and increased neurokinin-1 receptor (NK-1R) staining at all time points, maximal at 15 days. Correlation analyses at 45 days post-bCCI, were significant for individual rat nocifensive responses in each cold test and CCK and NK-1R, but not for MOR or NPY.</p> <p>Conclusions</p> <p>These results confirm the usefulness of cold testing in bCCI rats, a new approach using CCI to model neuropathic pain, and suggest a potential value of studying the roles of dorsal horn CCK and substance P in chronic neuropathic pain. Compared to human subjects with neuropathic pain, responses to cold stimuli in rats with bCCI may be a useful model of neuropathic pain.</p

Derivation of a screening tool to identify patients with right ventricular dysfunction or tricuspid regurgitation after negative computerized tomographic pulmonary angiography of the chest

Many dyspneic patients who undergo computerized tomographic pulmonary angiography (CTPA) for presumed acute pulmonary embolism (PE) have no identified cause for their dyspnea yet have persistent symptoms, leading to more CTPA scanning. Right ventricular (RV) dysfunction or overload can signal treatable causes of dyspnea. We report the rate of isolated RV dysfunction or overload after negative CTPA and derive a clinical decision rule (CDR). We performed secondary analysis of a multicenter study of diagnostic accuracy for PE. Inclusion required persistent dyspnea and no PE. Echocardiography was ordered at clinician discretion. A characterization of isolated RV dysfunction or overload required normal left ventricular function and RV hypokinesis, or estimated RV systolic pressure of at least 40 mmHg. The CDR was derived from bivariate analysis of 97 candidate variables, followed by multivariate logistic regression. Of 647 patients, 431 had no PE and persistent dyspnea, and 184 (43%) of these 431 had echocardiography ordered. Of these, 64 patients (35% [95% confidence interval (CI): 28%-42%]) had isolated RV dysfunction or overload, and these patients were significantly more likely to have a repeat CTPA within 90 days (P = .02, [Formula: see text] test). From univariate analysis, 4 variables predicted isolated RV dysfunction: complete right bundle branch block, normal CTPA scan, active malignancy, and CTPA with infiltrate, the last negatively. Logistic regression found only normal CTPA scanning significant. The final rule (persistent dyspnea + normal CTPA scan) had a positive predictive value of 53% (95% CI: 37%-69%). We conclude that a simple CDR consisting of persistent dyspnea plus a normal CTPA scan predicts a high probability of isolated RV dysfunction or overload on echocardiography

Randomized trial of inhaled nitric oxide to treat acute pulmonary embolism: The iNOPE trial

BACKGROUND: The study hypothesis is that administration of inhaled nitric oxide (NO) plus oxygen to subjects with submassive pulmonary embolism (PE) will improve right ventricular (RV) systolic function and reduce RV strain and necrosis, while improving patient dyspnea, more than treatment with oxygen alone. METHODS: This article describes the rationale and protocol for a registered (NCT01939301), nearly completed phase II, 3-center, randomized, double-blind, controlled trial. Eligible patients have pulmonary imaging-proven acute PE. Subjects must be normotensive, and have RV dysfunction on echocardiography or elevated troponin or brain natriuretic peptide and no fibrinolytics. Subjects receive NO plus oxygen or placebo for 24 hours (±3 hours) with blood sampling before and after treatment, and mandatory echocardiography and high-sensitivity troponin posttreatment to assess the composite primary end point. The sample size of N=78 was predicated on 30% more NO-treated patients having a normal high-sensitivity troponin (<14 pg/mL) and a normal RV on echocardiography at 24 hours with α=.05 and β=.20. Safety was ensured by continuous spectrophotometric monitoring of percentage of methemoglobinemia and a predefined protocol to respond to emergent changes in condition. Blinding was ensured by identical tanks, software, and physical shielding of the device display and query of the clinical care team to assess blinding efficacy. RESULTS: We have enrolled 78 patients over a 31-month period. No patient has been withdrawn as a result of a safety concern, and no patient has had a serious adverse event related to NO. CONCLUSIONS: We present methods and a protocol for the first double-blinded, randomized trial of inhaled NO to treat PE

Independent evaluation of a simple clinical prediction rule to identify right ventricular dysfunction in patients with shortness of breath

BACKGROUND: Many patients have unexplained persistent dyspnea after negative computed tomographic pulmonary angiography (CTPA). We hypothesized that many of these patients have isolated right ventricular (RV) dysfunction from treatable causes. We previously derived a clinical decision rule (CDR) for predicting RV dysfunction consisting of persistent dyspnea and normal CTPA, finding that 53% of CDR-positive patients had isolated RV dysfunction. Our goal is to validate this previously derived CDR by measuring the prevalence of RV dysfunction and outcomes in dyspneic emergency department patients. METHODS: A secondary analysis of a prospective observational multicenter study that enrolled patients presenting with suspected PE was performed. We included patients with persistent dyspnea, a nonsignificant CTPA, and formal echo performed. Right ventricular dysfunction was defined as RV hypokinesis and/or dilation with or without moderate to severe tricuspid regurgitation. RESULTS: A total of 7940 patients were enrolled. Two thousand six hundred sixteen patients were analyzed after excluding patients without persistent dyspnea and those with a significant finding on CTPA. One hundred ninety eight patients had echocardiography performed as standard care. Of those, 19% (95% confidence interval [CI], 14%-25%) and 33% (95% CI, 25%-42%) exhibited RV dysfunction and isolated RV dysfunction, respectively. Patients with isolated RV dysfunction or overload were more likely than those without RV dysfunction to have a return visit to the emergency department within 45 days for the same complaint (39% vs 18%; 95% CI of the difference, 4%-38%). CONCLUSION: This simple clinical prediction rule predicted a 33% prevalence of isolated RV dysfunction or overload. Patients with isolated RV dysfunction had higher recidivism rates and a trend toward worse outcomes

Inhaled nitric oxide to treat intermediate risk pulmonary embolism: A multicenter randomized controlled trial

Objective To test the hypothesis that adjunctive inhaled NO would improve RV function and viability in acute PE. Methods This was a randomized, placebo-controlled, double blind trial conducted at four academic hospitals. Eligible patients had acute PE without systemic arterial hypotension but had RV dysfunction and a treatment plan of standard anticoagulation. Subjects received either oxygen plus 50 parts per million nitrogen (placebo) or oxygen plus 50 ppm NO for 24 h. The primary composite endpoint required a normal RV on echocardiography and a plasma troponin T concentration <14 pg/mL. The secondary endpoint required a blood brain natriuretic peptide concentration <90 pg/mL and a Borg dyspnea score ≤ 2. The sample size of N = 76 tested if 30% more patients treated with NO would achieve the primary endpoint with 80% power and alpha = 5%. Results We randomized 78 patients and after two withdrawals, 38 were treated per protocol in each group. Patients were well matched for baseline conditions. At 24 h, 5/38 (13%) of patients treated with placebo and 9/38 (24%) of patients treated with NO reached the primary endpoint (P = 0.375). The secondary endpoint was reached in 34% with placebo and 13% of the NO (P = 0.11). In a pre-planned post-hoc analysis, we examined how many patients with RV hypokinesis or dilation at enrollment resolved these abnormalities; 29% more patients treated with NO resolved both abnormalities at 24 h (P = 0.010, Cochrane's Q test). Conclusions In patients with severe submassive PE, inhaled nitric oxide failed to increase the proportion of patients with a normal troponin and echocardiogram but increased the probability of eliminating RV hypokinesis and dilation on echocardiography

BMQ

BMQ: Boston Medical Quarterly was published from 1950-1966 by the Boston University School of Medicine and the Massachusetts Memorial Hospitals. Pages 49-52, v17n2, provided courtesy of Howard Gotlieb Archival Research Center