4,007 research outputs found
Towards a Powerful HardwareâinâtheâLoop System for Virtual Calibration of an OffâRoad Diesel Engine
A common challenge among internal combustion engine (ICE) manufacturers is shorten-ing the development time while facing requirements and specifications that are becoming more complex and border in scope. Virtual simulation and calibration are effective instruments in the face of these demands. This article presents the development of zeroâdimensional (0D)ârealâtime engine and exhaust afterâtreatment system (EAS) models and their deployment on a Virtual test bench (VTB). The models are created using a series of measurements acquired in a real test bench, carefully performed in view of ensuring the highest reliability of the models themselves. A zeroâdimensional approach was chosen to guarantee that models could be run in realâtime and interfaced to the real engine Electronic Control Unit (ECU). Being physically based models, they react to changes in the ECU calibration parameters. Once the models are validated, they are then integrated into a Sim-ulinkÂź based architecture with all the Inputs/Outputs connections to the ECU. This SimulinkÂź model is then deployed on a Hardware in the Loop (HiL) machine for ECU testing and calibration. The results for engine and EAS performance and emissions align with both steadyâstate and transient measurements. Finally, two different applications of the HiL system are presented to explain the opportunities and advantages of this tool integrated within the standard engine development. Ex-amples cited refer to altitude calibration activities and soot loading investigation on vehicle duty cycles. The cases described in this work are part of the actual development of one of the latest engines developed by Kohler Engines: the KDI 1903 TCR Stage V. The application of this methodology reveals a great potential for engine development and may become an essential tool for calibration engineers
Subclinical Hypothyroidism: behavioral and psychophysiological characteristics.A pilot study
Background: Clinical hypothyroidism affects various aspects of cognitive and affective brain function. The most severe hypothyroidism may also mimic a picture of melancholic depression and dementia. Subclinical hypothyroidism (SHT) is characterized by elevated TSH levels despite normal thyroid hormone concentrations. The aim of this research is to verify the presence of a typical psychophysiological pattern in SHT patients. Methods: Since 1998 fifty patients who underwent surgeries at the Department of Endocrinology, University of Pisa, diagnosed with SHT, were subsequently recruited. Subjects underwent an inspection of the reported symptoms using the Crown & Crisp Experiential Index, and a psychophysiological assessment with a simultaneous recording of the parameters Skin Conductance Level/ Response (SCL/SCR), Surface Frontal Electromyogram (EMG), Peripheral Temperature (PT), Heart Rate (HR). As a control group, fifty subjects without endocrine disorders were subsequently recruited. Results: Data shows little difference in levels in hormonal assays except for TSH. There is also a significant elevation of some of the CCEI subscales: Anxiety, Depression, and Somatic Complaints. At the autonomic level, there is a general pattern of excessive arousal with significant differences in SCL/SCR, HR, and PT. Conclusions: A first data interpretation is that in sub-clinical hypothyroidism, the body tries to support and integrate the general lack of energy with an acceleration of the autonomic activity. This condition of initial arousal could be a useful indicator in order to monitor the treatment course and its effectiveness on the pathological evolution
Blending mindfulness practices and character strengths increases employee wellâbeing : a secondâorder metaâanalysis and a followâup field experiment
Abstract: This study summarises the existing literature on MindfulnessâBased Interventions (MBIs) and their effect on employee wellâbeing criteria and extends it by testing MBIs against a MindfulnessâStrengthsâBased Intervention (MSBI). Given that extant MBIs focus on restoring wellâbeing, our first hypothesis was that MBIs would perform better on reducing negative emotional states than on promoting wellbeing. To test our first hypothesis, we conducted a secondorder metaâanalysis, which summarised 13 firstâorder metaâanalyses (k = 311). MBIs had stronger effects on reducing negative emotions (g = â0.74) than on increasing wellâbeing (g = 0.58). Then, we conducted a followâup field experiment, comparing how an MSBI performed against an MBI on employee wellâbeing criteria..
Outcome at 2-year of treatment in first-episode psychosis patients who were enrolled in a specialized early intervention program
Treatment in early intervention services (EIS) seems superior to treatment as usual on several outcomes, but the extent of heterogeneity in response is unclear. In this study, treatment response trajectories up to 2 years in first-episode psychosis (FEP) patients enrolled in an Italian early intervention service (EIS) have been quantified. The 24-item Brief Psychiatric Rating Scale (BPRS) was used to quantify treatment response up to 2 years in 129 participants. Conditional growth modeling and latent class growth analysis were used to test changes over time in the BPRS and separation into independent classes over time. Group differences were tested on socio-demographic and clinical variables known to be related to outcome in psychosis. Scores on the BPRS showed a statistically significant decrease in overall scores across all tested models. Four trajectories were identified across 2 years. Most patients showed a progressive decrease in the BPRS scores; a scant fraction showed a more stepped decrease from very high levels of psychopathology. No potential predictor was statistically related to the time course of BPRS scores. Most patients that undergo treatment within an EIS are characterized by amelioration, but patients that have higher baseline scores of psychopathology require more intensive treatment
Coping with systemic lupus erythematosus in patients' words
Objective Previous research on coping strategies of patients with SLE showed that there are no absolute adaptive or maladaptive strategies and that the range of potential coping strategies is large and heterogeneous. In this paper, we aimed to identify, in a large sample of patients with SLE (N=3222), the most frequent words used by patients to describe their coping strategies, to group them into significant themes and to test their possible association with specific patient characteristics. Methods Our analyses were based on the data set of the European survey 'Living with Lupus in 2020' (N=3222). Through the T-LAB software, we analysed the answers that adult participants gave to an open-ended question about how they cope with the disease. We identified the most frequent words, and with hierarchical cluster analysis we grouped them into semantic clusters (ie, themes) that were characterised by specific patterns of words. Finally, we tested the possible association between clusters and illustrative variables (sociodemographics, disease characteristics, quality of life). Results Five coping strategies were identified, each of them constituting an important percentage of the total word occurrences: positive attitude (22.58%), social support (25.46%), medical treatments (10.77%), healthy habits (20.74%) and avoid stress (20.45%). Each strategy was statistically associated with specific patient characteristics, such as age and organ involvement. Conclusions Learning to adapt to a lifetime of having SLE may require replacing old coping strategies with more effective ones. Investigating patients' coping strategies in relation to different patient characteristics represents a useful starting point for developing more targeted and efficacious interventions
The situational version of the brief COPE: Dimensionality and relationships with goal-related variables
This study is aimed at investigating the dimensionality of the situational version of the Brief COPE, a questionnaire that is frequently used to assess a broad range of coping responses to specific difficulties, by comparing five different factor models highlighted in previous studies. It also aimed at exploring the relationships among coping responses, personal goal commitment and progress. The study involved 606 adults (male = 289) ranging in age from 19 to 71. Using confirmatory factor analysis, we compared five models and assessed relationships of coping responses with goal commitment and progress. The results confirmed the theoretical factor structure of the situational Brief COPE. All the 14 dimensions showed acceptable reliability and relationships with goal commitment and progress, attesting the reliability and usefulness of this measure to evaluate coping responses to specific events
Time-course of clinical symptoms in young people at ultra-high risk for transition to psychosis
Vertigo and dizziness in children: An update
Background: Vertigo and dizziness are relatively infrequent in paediatric patients, but specific data on the prevalence of these disorders are limited and influenced by various factors, including the age of the examined population. These conditions often have a significant impact on patientsâ and parentsâ quality of life. The aim of this paper is to investigate the prevalence of different aetiologies of vertigo in the paediatric population through a systematic review. Methods: According to PRISMA guidelines, a systematic review of the literature was performed. Medline and Embase were searched from January 2011 through to 10 September 2021. The search yielded 1094 manuscripts, which were reduced to 7 upon the application of inclusion criteria. Results: A total of 2470 paediatric patients were evaluated by the selected papers. Vestibular Migraine was the most frequently diagnosed condition, occurring alone or in association with other diseases. Overall, audio-vestibular disorders represented the second cause of vertigo, and the prevalence appears to increase according to age growth. Over the years, even though we assisted in the amelioration of diagnostic rates, partially related to an improvement in diagnostic tools, the aetiology of vertigo remains still unclear in a variable percentage of patients. Conclusion: Vertigo in children, despite being an uncommon symptom, requires a multidisciplinary approach, often involving Paediatricians, Neurologists and Otorhinolaryngologists. A comprehensive evaluation of children suffering from vertigo is crucial for establishing a successful therapy and reducing parental worries
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