Heterogeneity of depression across the socioeconomic spectrum

Why is low socioeconomic status associated with high rates of depression? And, is the surplus of depression at lower SES just more of the same type as depression found at higher levels, or distinctive? We addressed these questions by examining the relations among SES, amygdala volume and symptoms of depression in healthy young adults. Amygdala volume, a risk factor for depression, does not synergize with SES in a diathesis-stress relation, nor does it mediate the relation of SES to depression. Rather, SES and amygdala volume are independent, additive risk factors. They are also associated with different depression symptoms and, whereas perceived stress fully mediates the relation of SES to depression, it has no relation to amygdala volume. These findings suggest heterogeneity of depression across the socioeconomic spectrum, with implications for treatment selection as well as for future genetic and imaging studies.

Investigation of electromechanical impedance and residual stress relation for samples machined by hot ultrasonic-assisted turning

Electromechanical impedance (EMI) method has been widely used in recent years to evaluate the condition of structures. In this method, piezoelectric sensors are added to the structure to examine material properties. The impedance/admittance signals are recorded with the aid of the impedance analyzer without any conversion. When there is any change in structures, differences occur in these signals. Thus, changes in structures can be easily determined. It is known that residual stress plays a vital role in materials in terms of crack initiation, breakage, fatigue life, etc. In contrast, the detection of residual stress is time-consuming and it requires experience. This study reveals the effect of cutting parameters on residual stress and electromechanical impedance/admittance values. Firstly, hot ultrasonic-assisted turning was performed for Ti6Al4V material. A parametric study was carried out with different cutting depth, feed rate, and cutting speed. In the second stage, residual stress values measured by X-Ray diffraction (XRD) method and impedance/admittance values measured by an impedance analyzer were compared. In this context, empirical equations with their values between stress/impedance–admittance values have been derived. In general, it has been observed that stress values are significantly associated with impedance/admittance values and the highest correlation was obtained with the reactance values.

Analytical method to accurately estimate overpressure magnitude: The case study from Indonesia's Tertiary basins

The most widely used overpressure estimation method is empirical method such as Eaton’s method. The nature of the empirical method is that it may work well in one area, but it may not work in other areas. In this paper, we try to develop more analytical approach to estimate overpressure, with the basis on understanding of overpressure generation. We then try to apply this method in Indonesia’s Tertiary basins, and it gives sensible results. The overpressure generating mechanism is analysed by direct inspection and comparison of sonic (and resistivity) vs density log responses to overpressure. From this step, we can understand whether overpressure is caused by disequilibrium compaction, unloading, or both. In the case that overpressure is generated by disequilibrium compaction mechanism, simple velocity-effective stress relation or equivalent depth method gives good match between estimated and measured pore pressure. If disequilibrium compaction and unloading contribute to overpressure, two steps are required to estimate overpressure magnitude. The first step is to analyse log response due to disequilibrium compaction and calculate disequilibrium compaction overpressure magnitude by methods as discussed above. The second step is to calculate the contribution of disequilibrium compaction and unloading to overpressure, based on effective stress history that has ever been experienced by sediments. By applying this two steps procedure, overpressure magnitude can be estimated accurately.

Cluster analysis in the studying of stress relation in the Vrancea-zone

<p>The SE-Carpathians produce significant geodynamic activity due to the current subduction process. The strong seismicity in the Vrancea-zone is its most important indicator. The focus area of these seismic events is relatively small, around 80*100 km and the distribution of their locations is quiet dense.</p><p>The authors have carried out cluster analyses of the focal mechanism solutions estimated from local and tele-seismic measurements and stress inversions to support the recent and previously published studies in this region. They have applied different pre-existing clustering methods – e.g. HDBSCAN (hierarchical density-based clustering for applications with noise) and agglomerative hierarchical analysis – considering to the geographical coordinates, focal depths and parameters of the focal mechanism solutions of the used seismic events, as well. Moreover, they have attempted to improve a fully-automated algorithm for the classification of the earthquakes for the estimations. This algorithm does not call for the setting of hyper-parameters, thus the affection of the subjectivity can be reduced significantly and the running time can be also decreased. In all cases, the resulted stress tensors are in close agreement with the earlier presented results.</p>

Simple Method for DTS/DSS Data Interpretation: An Application to Pipeline Geotechnical Monitoring

Geotechnical monitoring based on optical fiber sensor technology has been used over more than a decade to detect hazards than can affect the integrity of pipelines. In particular when these sensors are implemented in the form of distributed temperature and strain sensors, respectively known as DTS and DSS, they provide information about hazard location and spatial extension. In addition, these sensors can capture the speed at which the event developing in particular when implemented as a permanent monitoring solution. So far these sensors were implemented as part of an alarming system detecting events such as landslides, erosion and subsidence. The current work aims at presenting simple method to extract additional information about the hazard such as the amplitude of the soil displacement in the case of landslides and subsidence or dirt cover for erosion. Estimation of stress in soil is also discussed based on the cable strain-stress relation obtained from the sensing cable qualification. The approach is validated by academic works conducted in parallel of the technology development. The method use is then illustrated by its application to field data collected from several events occurred over the past 10 years.