66,246 research outputs found
Does Trauma Change the Way Individuals with Post-Traumatic Stress Disorder (PTSD) Deal with Positive Stimuli?
No full textIntroduction: Post-Traumatic Stress Disorder (PTSD) is a highly prevalent disorder and a highly debilitating condition. Although current theories focused on depressed mood and intrusion as critical dimensions, the mechanism through which depression increases the risk of PTSD remains unclear. Research usually concentrates on the hyperactive negative valence system (NVS) (e.g., increased fear and threat responses), but some evidence suggests a significant role for the hypoactive positive valence system (PVS) (e.g., less neural activation towards rewards). Method: The main aim of the present research was to investigate whether probable PTSD leads to a different evaluation of the implicit processing in a refugee's sample. Ratings of arousal, dominance, and valence from 60 International Affective Picture System (IAPS) pictures (positive, neutral, and negative) were collected from 42 individuals with probable PTSD, and a group of 26 trauma-exposed individuals (M-age = 28.49 years, SD = +/- 7.78). Results: ANOVA results revealed a main group effect (eta 2p = 0.379) on arousal, dominance, valence dimensions, and pictures' categories (eta 2p = 0.620), confirming evidence according to which PTSD origins a state of maladaptive hyperarousal and troubles the regulation of emotions, and not supporting the view that such difficulties arise only with negative stimuli. Participants with probable PTSD deemed negative stimuli as more threatening than they really are, reacting to unpleasant images with greater negative emotionality (i.e., enhanced arousal and lower valence ratings) compared with individuals without PTSD. Moreover, they rated positive stimuli as less pleasant. Furthermore, arousal ratings were negatively correlated with valence (r = -0.709, p < 0.01) indicating that pictures with high arousal (negative) were associated with lower valence. Discussion: Our findings supported evidence according to which PTSD caused a constant state of hyperarousal and difficulties in regulating emotions facing environmental stimuli. Positive stimuli are considered less pleasant, and this inhibits from completely benefiting from them. Conclusion: Our study provides evidence for a differential and potentially complementary involvement of NVS and PVS in PTSD development. Intervention for PTSD may, thus, target both negative and positive valence processing
Thermal effects on optical performances of a prefocussing mirror for high-resolution soft-x-ray beamlines
No full textHeating of grazing incidence mirror surfaces by absorbed soft X-rays from a synchrotron beamline has been studied numerically to evaluate resultant displacements of the thermally loaded surface. Subsequent ray-tracing analysis has provided the corresponding change in optical performances. This procedure has been applied in particular to a thermally loaded prefocussing ellipsoidal mirror to be used in a high-spectral-resolution soft-X-ray beamline in the U2 undulator beamline of ELETTRA, and ultrahigh brightness synchrotron radiation facility under construction in Trieste. Various cooling geometries have been investigated. A detailed analysis of the results indicates deterioration of imaging properties beyond the present fabrication tolerances only at extreme irradiation levels
A numerical procedure based on orowan's theory for predicting the behavior of the cold rolling mill process in full film lubrication
No full textIn this paper, a numerical model for predicting the working parameters of the cold rolling
mill process in full film lubrication is presented. The model is useful from an industrial point
of view, because it can forecast the thickness reduction of the metal sheet and the pressure trend,
so that the rolling mill process parameters can be regulated to obtain a specific output thickness.
Experimental tests were performed, and results are compared to the theoretical ones resulting from
the model. The novelty of the proposed model is that it combines Orowan’s theory for the plastic
deformation analysis with the Reynolds equation in full film lubrication and the continuity conditions.
The lubricant flow and viscosity are studied, taking in account their dependence on pressure and
temperature. The proposed model describing the full film regime is also compared to another one,
previously proposed by the authors, based on the well-known slab analysis and sharing with it the
representation of the lubrication regime, the mathematical procedure, and the boundary conditions.
The results show that the proposed model provides a better prediction of the working parameters
with respect to the model based on the slab analysi
History of alcohol consumption and cancer burden in Italy
No full textThis decline in alcohol consumption led to substantial declines in cirrhosis and other chronic liver diseases including liver cancer, and in all major alcohol related cancers (oral cavity and pharynx, oesophagus, larynx, liver, and also breast) in the last few decades in Italy. However, the favourable trends in alcohol-related mortality in Italy and other Mediterranean countries are not reflected in Central-Northern Europe and the USA. Thus, alcohol remains a major cause of cancer and other diseases in Europe
Degradation of Image Quality Induced by Thermal Loads and Slope Errors in a XUV High Resolution Synchrotron Radiation Monochromator
No full textThe limiting effects to the performances of an optical device, such as an XUV monochromator inserted in a synchrotron radiation facility, are mainly manufacturing slope errors and thermal loads induced by the optical beam itself. We have performed numerical simulations on such effects in the low energy section of a high resolution, wide spectral range monochromator for the storage ring ELETTRA in Trieste. The instrument will be used in the dedicated surface physics beamline ALOISA (advanced line for overlayer interface and surface analysis). Thermal effects have been evaluated by using finite element analysis. Thermal induced deformations and slope errors have been included in a ray tracing program. The resulting aberrations at the output of the instrument have been evaluated for the extreme conditions of maximum power density and asymmetrical illumination of the second mirror. The results stress the relevance of manufacturing slope errors in limiting spatial and spectral resolution
Potential for improvement in cancer management : reducing mortality in the European Union
No full textOverall age-standardized cancermortality rates in the European Union (EU) have declined by approximately 20% through 2010 (17% in women, 22% in men) since the peak value reached in 1988.This corresponds to the avoidance of more than 250,000 cancer deaths in 2010 alone and approximately 2.2 million deaths over the1989-2010 22-year period.Amore than twofold difference remains between the highest cancer mortality rates (in Hungary and other central European countries) and the lowest (in selectedNordic countries andSwitzerland).Part of this gap is due to tobacco, alcohol, and other lifestyle and environmental exposures, and another part is attributable to differences in cancer diagnosis, treatment, and management. There are also appreciable differences in 5-year cancer survival across the EU, with lower survival rates in central and eastern Europe. If overall cancer survival in EU countries with low rates could be raised to the median, approximately 50,000 additional cancer deaths would be avoided per year, and more than 100,000 would be avoided if overall survival in all countries were at least that of the 75% percentile-4% and 8%, respectively, of the approximately 1.3 million cancer deaths registered in the EU in 2010. There is, however, substantial uncertainty about any such estimate because differences in cancer survival are partly or largely attributable to earlier diagnosis, in variable proportion for each cancer site and probably to different degrees in different countries, even in the absence ofchanges in the date ofdeath or avoidance of death. Consequently, these approximations are the best available andmay be used cautiously to compare countries, health care approaches, and changes that occur over time
Contact mechanics analysis of a soft robotic fingerpad
No full textThe precision grasping capabilities of robotic hands is a key feature which is more and more required in the manipulation of objects in several unstructured fields, as for instance industrial, medical, agriculture and food industry. For this purpose, the realization of soft robotic fingers is crucial to reproduce the human finger skills. From this point of view the fingerpad is the part which is mostly involved in the contact. Particular attention must be paid to the knowledge of the mechanical contact behavior of soft artificial fingerpads. In this paper, artificial silicone fingerpads are applied to the last phalanx of robotic fingers actuated by tendons. The mechanical interaction between the fingerpad and a flat surface is analyzed in terms of deformations, contact areas and indentations. A reliable model of fingertip deformation properties provides important information for understanding robotic hand performance, that can be useful both in the design phase and for defining control strategies. The approach is based on theoretical, experimental, and numerical methods. The results will be exploited for the design of more effective robotic fingers for precision grasping of soft or fragile objects avoiding damages
Reply to the letter to the editor 'European cancer mortality predictions for the year 2019 with focus on breast cancer, by Malvezzi M et al' by Marsden and Hamoda, on behalf of the British Menopause Society Medical Advisory Council
No full textDesign of soft grippers with modular actuated embedded constraints
No full textUnderactuated, modular and compliant hands and grippers are interesting solutions in grasping and manipulation tasks due to their robustness, versatility, and adaptability to uncertainties. However, this type of robotic hand does not usually have enough dexterity in grasping. The implementation of some specific features that can be represented as “embedded constraints” allows to reduce uncertainty and to exploit the role of the environment during the grasp. An example that has these characteristics is the Soft ScoopGripper a gripper that has a rigid flat surface in addition to a pair of modular fingers. In this paper, we propose an upgraded version of the Soft ScoopGripper, developed starting from the limits shown by the starting device. The new design exploits a modular structure to increase the adaptability to the shape of the objects that have to be grasped. In the proposed device the embedded constraint is no rigid neither unactuated and is composed of an alternation of rigid and soft modules, which increase versatility. Moreover, the use of soft material such as thermoplastic polyurethane (TPU) reduces the risk of damage to the object being grasped. In the paper, the main design choices have been exploited and a finite element method (FEM) analysis through static simulation supports a characterization of the proposed solution. A complete prototype and some preliminary tests have been presented
Grasping with the SoftPad, a Soft Sensorized Surface for Exploiting Environmental Constraints with Rigid Grippers
No full textA common trend in robotic manipulation is to build compliant hands that can exploit environmental constraints to perform robust grasps. However, in large-scale industrial applications, end-effectors are mostly rigid. How can we exploit environmental constraints using rigid industrial grippers? We propose to add compliance to the environment, thanks to a soft modular pneumatic surface: the SoftPad. Pressure sensors connected to its modules allow to estimate the object pose and center of mass and to detect the contact between the gripper and the SoftPad during a grasping task. A new grasp strategy that exploits such information for top-grasping objects, without using cameras or force sensors, is presented. It has been tested with objects having a wide range of sizes, shapes, and weights. The SoftPad design can easily be adapted to the set of objects that are used in a certain application
- …
