Search

Objective: Preoperative negative affect is a risk factor for worse postoperative pain, but research investigating this association among patients undergoing thoracic surgery is inconsistent. Additionally, female patients often report greater negative affect and postoperative pain than males. This prospective observational study investigated the association between preoperative negative affect and postoperative pain after thoracic surgery and whether this association differed by sex. Methods: Patients (n = 105) undergoing thoracic surgery completed preoperative assessments of pain and negative affect (PROMIS anxiety and depression short forms). Patients reported their daily worst pain over the first 7 postoperative days, and an index score of acute postoperative pain was created. Six months after surgery, a subsample of patients (n = 60) reported their worst pain. Results: Higher levels of preoperative anxiety (r = 0.25, p = 0.011) and depression (r = 0.20, p = 0.042) were associated with greater acute postoperative pain, but preoperative negative affect was not related to chronic postsurgical pain (anxiety: r = 0.19, p = 0.16; depression: r = −0.01, p = 0.94). Moderation analyses revealed that the associations between both preoperative anxiety (b = 0.12, 95% CI [0.04, 0.21], p = 0.004) and depression (b = 0.15, 95% CI [0.04, 0.26], p = 0.008) with acute postoperative pain were stronger among females than males. Similarly, the association between preoperative anxiety and chronic postsurgical pain was stronger among females (b = 0.11, 95% CI [0.02, 0.20], p = 0.022), but the association between preoperative depression and chronic pain did not differ based on sex (b = 0.13, 95% CI [−0.07, 0.34], p = 0.201]). Conclusions: Our findings suggest that negative affect may be especially important to the experience of pain following thoracic surgery among female patients, whose degree of preoperative anxiety may indicate vulnerability to progress to a chronic pain state. Preoperative interventions aimed at reducing negative affect and pain may be particularly useful among females with high negative affect before thoracic surgery. [ABSTRACT FROM AUTHOR]

Objective Pain is a variably experienced symptom during pregnancy, and women scheduled for cesarean delivery, an increasingly common procedure, are a relatively understudied group who might be at higher pain risk. Although biopsychosocial factors are known to modulate many types of chronic pain, their contribution to late pregnancy pain has not been comprehensively studied. We aimed to identify biopsychosocial factors associated with greater pain severity and interference during the last week of pregnancy. Methods In this prospective, observational study, 662 pregnant women scheduled for cesarean delivery provided demographic and clinical information and completed validated psychological and pain assessments. Multivariable hierarchical linear regressions assessed independent associations of demographic, clinical, and psychological characteristics with pain severity and pain interference during the last week of pregnancy. Results Women in the study had a mean age of 34 years, and 73% identified as White, 11% as African American, 10% as Hispanic/Latina, and 6% as Asian. Most women (66%) were scheduled for repeat cesarean delivery. Significant independent predictors of worse pain outcomes included identifying as African American or Hispanic/Latina and having greater depression, sleep disturbance, and pain catastrophizing. Exploratory analyses showed that women scheduled for primary (versus repeat) cesarean delivery reported higher levels of anxiety and pain catastrophizing. Conclusions Independent of demographic or clinical factors, psychological factors, including depression, sleep disturbance, and pain catastrophizing, conferred a greater risk of late pregnancy pain. These findings suggest that women at higher risk of pain during late pregnancy could benefit from earlier nonpharmacological interventions that concurrently focus on psychological and pain symptoms. [ABSTRACT FROM AUTHOR]

The reduction stripping kinetics of Ce4+ by HEH/EHP was studied by a constant interfacial area cell with laminar flow. The effects of stirring speed, temperature, specific interfacial area, Ce4+ concentration in the organic phase, free extractant concentration in the organic phase, HCl concentration, and H2O2 concentration on the stripping rate were investigated. The control mode and control steps of stripping process were judged. The kinetic equation of stripping was derived. The mechanism of stripping process was discussed. The results show that the stripping process is controlled by both diffusion and interfacial chemical reaction. The apparent activation energy Ea was calculated using Arrhenius's formula. The kinetic equation of Ce4+ reduction stripping is R = k[Ce4+](o)1.08[HEH/EHP](o)−1.03[H+](a)0.99[H2O2](a)0.53, and the apparent rate constant k is 10−3.66 (mol−0.57·L0.57)/min. [ABSTRACT FROM AUTHOR]

Highlights: [•] Coordination properties of CeF x 4−x and BF y 3−y were investigated by complexometric potentiometric titration. [•] The fluorine was recovered as KBF4 before extractive separation of rare earths. [•] Fluorine can be separated from cerium from fluorine-bearing rare earth sulfate solution. [ABSTRACT FROM AUTHOR]