Evolution of the zirconium alloy Zr-1Nb defect structure after cold rolling

Zirconium alloys are actively used in nuclear power engineering. During the operation of these alloys, it is necessary to know the change in structural, mechanical and physical characteristics when using material in corrosive environments. In this regard, it is necessary to study the occurrence of certain defects in the material and their effect. Such defects include dislocations. This study is aimed to study the processes of the appearance and distribution of dislocations in a material by positron annihilation spectroscopy. As a result of this work, the lifetime of positrons in the dislocation of zirconium was determined and the character of dislocation distribution at different degrees of deformation was presented

Procedure-specific Risk Factor Analysis for the Development of Severe Postoperative Pain

Background: Many studies have analyzed risk factors for the development of severe postoperative pain with contradictory results. To date, the association of risk factors with postoperative pain intensity among different surgical procedures has not been studied and compared. Methods: The authors selected precisely defined surgical groups (at least 150 patients each) from prospectively collected perioperative data from 105 German hospitals (2004-2010). The association of age, sex, and preoperative chronic pain intensity with worst postoperative pain intensity was studied with multiple linear and logistic regression analyses. Pooled data of the selected surgeries were studied with random-effect analysis. Results: Thirty surgical procedures with a total number of 22,963 patients were compared. In each surgical procedure, preoperative chronic pain intensity and younger age were associated with higher postoperative pain intensity. A linear decline of postoperative pain with age was found. Females reported more severe pain in 21 of 23 surgeries. Analysis of pooled surgical groups indicated that postoperative pain decreased by 0.28 points (95% CI, 0.26 to 0.31) on the numeric rating scale (0 to 10) per decade age increase and postoperative pain increased by 0.14 points (95% CI, 0.13 to 0.15) for each higher score on the preoperative chronic pain scale. Females reported 0.29 points (95% CI, 0.22 to 0.37) higher pain intensity. Conclusions: Independent of the type and extent of surgery, preoperative chronic pain and younger age were associated with higher postoperative pain. Females consistently reported slightly higher pain scores regardless of the type of surgery. The clinical significance of this small sex difference has to be analyzed in future studies

Procedure-specific Risk Factor Analysis for the Development of Severe Postoperative Pain

Background: Many studies have analyzed risk factors for the development of severe postoperative pain with contradictory results. To date, the association of risk factors with postoperative pain intensity among different surgical procedures has not been studied and compared. Methods: The authors selected precisely defined surgical groups (at least 150 patients each) from prospectively collected perioperative data from 105 German hospitals (2004-2010). The association of age, sex, and preoperative chronic pain intensity with worst postoperative pain intensity was studied with multiple linear and logistic regression analyses. Pooled data of the selected surgeries were studied with random-effect analysis. Results: Thirty surgical procedures with a total number of 22,963 patients were compared. In each surgical procedure, preoperative chronic pain intensity and younger age were associated with higher postoperative pain intensity. A linear decline of postoperative pain with age was found. Females reported more severe pain in 21 of 23 surgeries. Analysis of pooled surgical groups indicated that postoperative pain decreased by 0.28 points (95% CI, 0.26 to 0.31) on the numeric rating scale (0 to 10) per decade age increase and postoperative pain increased by 0.14 points (95% CI, 0.13 to 0.15) for each higher score on the preoperative chronic pain scale. Females reported 0.29 points (95% CI, 0.22 to 0.37) higher pain intensity. Conclusions: Independent of the type and extent of surgery, preoperative chronic pain and younger age were associated with higher postoperative pain. Females consistently reported slightly higher pain scores regardless of the type of surgery. The clinical significance of this small sex difference has to be analyzed in future studies

Correlates of satisfaction with pain treatment in the acute postoperative period : Results from the international PAIN OUT registry

Patient ratings of satisfaction with their postoperative pain treatment tend to be high even in those with substantial pain. Determinants are poorly understood and have not previously been studied in large-scale, international datasets. PAIN OUT, a European Union-funded acute pain registry and research project, collects patient-reported outcome data on postoperative day 1 using the self-reported International Pain Outcome Questionnaire (IPO), and patient, clinical, and treatment characteristics. We investigated correlates of satisfaction and consistency of effects across centres and countries using multilevel regression modelling. Our sample comprised 16,868 patients (median age 55years; 55% female) from 42 centres in 11 European countries plus Israel, USA, and Malaysia, who underwent a wide range of surgical procedures, for example, joint, limb, and digestive tract surgeries. Median satisfaction was 9 (interquartile range 7-10) on a 0-10 scale. Three IPO items showed strong associations and explained 35% of the variability present in the satisfaction variable: more pain relief received, higher allowed participation in pain treatment decisions, and no desire to have received more pain treatment. Patient factors and additional IPO items reflecting pain experience (eg, worst pain intensity), pain-related impairment, and information on pain treatment added little explanatory value, partially due to covariate correlations. Effects were highly consistent across centres and countries. We conclude that satisfaction with postoperative pain treatment is associated with the patients' actual pain experience, but more strongly with impressions of improvement and appropriateness of care. To the degree they desire, patients should be provided with information and involved in pain treatment decisions

Patients' perception of postoperative pain management: validation of the International Pain Outcomes (IPO) questionnaire

UNLABELLED: PAIN OUT is a European Commission-funded project aiming at improving postoperative pain management. It combines a registry that can be useful for quality improvement and research using treatment and patient-reported outcome measures. The core of the project is a patient questionnaire-the International Pain Outcomes questionnaire-that comprises key patient-level outcomes of postoperative pain management, including pain intensity, physical and emotional functional interference, side effects, and perceptions of care. Its psychometric quality after translation and adaptation to European patients is the subject of this validation study. The questionnaire was administered to 9,727 patients in 10 languages in 8 European countries and Israel. Construct validity was assessed using factor analysis. Discriminant validity assessment used Mann-Whitney U tests to detect mean group differences between 2 surgical disciplines. Internal consistency reliability was calculated as Cronbach's alpha. Factor analysis resulted in a 3-factor structure explaining 53.6% of variance. Cronbach's alpha at overall scale level was high (.86), and for the 3 subscales was low, moderate, or high (range, .53-.89). Significant mean group differences between general and orthopedic surgery patients confirmed discriminant validity. The psychometric quality of the International Pain Outcomes questionnaire can be regarded as satisfactory. PERSPECTIVE: The International Pain Outcomes questionnaire provides an instrument for postoperative pain assessment and improvement of quality of care, which demonstrated good psychometric quality when translated into a variety of languages in a large European and Israeli patient population. This measure provides the basis for the first comprehensive postoperative pain registry in Europe and other countries