Comparison of the prognostic value of early-phase proton magnetic resonance spectroscopy and diffusion tensor imaging with serum neuron-specific enolase at 72 h in comatose survivors of out-of-hospital cardiac arrest-a substudy of the XeHypotheca trial

Purpose: We compared the predictive accuracy of early-phase brain diffusion tensor imaging (DTI), proton magnetic resonance spectroscopy (1H-MRS), and serum neuron-specific enolase (NSE) against the motor score and epileptic seizures (ES) for poor neurological outcome after out-of-hospital cardiac arrest (OHCA).Methods: The predictive accuracy of DTI, 1H-MRS, and NSE along with motor score at 72 h and ES for the poor neurological outcome (modified Rankin Scale, mRS, 3 - 6) in 92 comatose OHCA patients at 6 months was assessed by area under the receiver operating characteristic curve (AUROC). Combined models of the variables were included as exploratory.Results: The predictive accuracy of fractional anisotropy (FA) of DTI (AUROC 0.73, 95% CI 0.62-0.84), total N-acetyl aspartate/total creatine (tNAA/tCr) of 1H-MRS (0.78 (0.68 - 0.88)), or NSE at 72 h (0.85 (0.76 - 0.93)) was not significantly better than motor score at 72 h (0.88 (95% CI 0.80-0.96)). The addition of FA and tNAA/tCr to a combination of NSE, motor score, and ES provided a small but statistically significant improvement in predictive accuracy (AUROC 0.92 (0.85-0.98) vs 0.98 (0.96-1.00), p = 0.037).Conclusion: None of the variables (FA, tNAA/tCr, ES, NSE at 72 h, and motor score at 72 h) differed significantly in predicting poor outcomes in this patient group. Early-phase quantitative neuroimaging provided a statistically significant improvement for the predictive value when combined with ES and motor score with or without NSE. However, in clinical practice, the additional value is small, and considering the costs and challenges of imaging in this patient group, early-phase DTI/MRS cannot be recommended for routine use.</p

Numerical studies of frictional responses when cutting hybrid CFRP/Ti composite

In manufacturing sectors, machining hybrid CFRP/Ti is usually an extremely challenging task due to the disparate natures of each stacked constituent involved and their respectively poor machinability. The current research focus of hybrid CFRP/Ti cutting was primarily made via the experimental studies, which exhibited high cost and time consuming. In this paper, a new contribution was provided to study the key frictional responses dominating the bi-material machining via the numerical approach. To this aim, a multi-physical model was developed by implementing different constitutive laws and damage criteria to construct the anisotropic machinability of the stacked composite. The interrelated effects of the multi-toolwork frictional behavior on hybrid CFRP/Ti cutting were precisely investigated with respect to the specific cutting energy consumption, machined surface morphology, and affected subsurface damage. A special focus was made to clarify the cutting sequence’s influences on the hybrid cutting operation. The numerical results highlighted the reasonable CFRP→Ti cutting sequence for hybrid composite machining and the pivotal role of multi-tool-work interaction in affecting the frictional responses induced by cutting

Pain and Functional Impairment as Mediators of the Link between Medical Symptoms and Depression in Type 2 Diabetes

Background: Among people with diabetes, depression is more common and is associated with greater morbidity and mortality. A better understanding of mechanisms underlying the link between poor health and depression is needed. Pain and functional impairment may account for the effect of poor health on depression in diabetes. Purpose: The purpose of the study was to examine whether pain and functional impairment mediate the association between diabetes-related medical symptoms and depression in type 2 diabetes. Method: Adults diagnosed with type 2 diabetes (N = 77) completed the following measures: Patient Health Questionnaire (PHQ), Diabetes Symptom Checklist (DSC), and Medical Outcomes Study 12-item Short-Form Health Survey (SF-12). Body mass index (BMI) was computed using height and weight data from medical records. Mediation and linear regression analyses were conducted. Results: Pain and functional impairment made significant, independent contributions to depression. Functional impairment mediated the link between diabetes-related medical symptoms and depression. Pain mediated the association between higher BMI and depression. Conclusion: Pain and functional impairment appear to play important, independent roles in depression in type 2 diabetes. Mediation analyses suggest the following: 1. diabetes-related medical problems increase functional impairment, which in turn leads to greater depression; and 2. the burden of carrying greater body mass (higher BMI) increases pain, which leads to increased depression