1,721,048 research outputs found
Enhancement of the Synthetic Storm Technique for the Prediction of Rain Attenuation Time Series at EHF
Full text linkA physically based rain attenuation prediction model for Earth-space links, namely the enhanced synthetic storm technique (E-SST), is presented. Different from the original SST, the E-SST receives as input detailed information on the rain height and on the storm velocity, and it discriminates between stratiform and convective rain events having a different impact on the link. The rain attenuation prediction accuracy of E-SST, both as applied directly and as embedded into a more accurate frequency scaling technique, is evaluated against a full year of propagation data collected by the NASA equipment installed at Politecnico di Milano in the frame of the Alphasat Aldo Paraboni propagation experiment. To this aim, a novel methodology to isolate the contribution of rain attenuation from the received beacon power is devised and presented. Results indicate that E-SST represents an accurate and reliable tool for the prediction of rain attenuation at EHF, both on a statistical basis (direct application) and on an event basis (frequency scaling)
On combining attenuation statistics of different tropospheric effects affecting EHF earth-space links
No full textThree attenuation statistics combination methods are evaluated and compared in this contribution for the first time using a consistent set of propagation data used as input and as a reference to test the methods' performance. The three approaches, which rely upon different statistical assumptions, aim at estimating the total tropospheric attenuation statistics by combining the complementary cumulative distribution functions of the attenuation associated to the different tropospheric impairments, namely clouds, gases, rain, and scintillations. The prediction performance tests are conducted, using as reference, the propagation data (19.7 and 39.4 GHz) collected in Milan, Italy, in the framework of the Alphasat Aldo Paraboni propagation experiment during 2017 and 2018. Results indicate that the combination method included in the inforce recommendation ITU-R P.618-13 provides the highest performance at both bands
Assessing Discriminant Validity through Structural Equation Modeling: The Case of Eating Compulsivity
Full text linkFood addiction (FA) and disordered eating behaviors related to obesity are gaining attention in clinical and research fields. The modified Yale Food Addiction Scale 2.0 (mYFAS2.0) is the gold standard questionnaire to measure FA, while another tool is the Measure of Eating Compulsivity 10 (MEC10). Discriminant validity is present when two measures of similar but distinct constructs show a correlation that is low enough for the factors to be regarded as distinct. However, the discriminant validity of these measures has never been tested. Through a cross-sectional study design, 717 inpatients (females: 56.20%, age: 53.681 ± 12.74) with severe obesity completed the MEC10, Binge Eating Scale (BES), and mYFAS2.0. A structural equation model (SEM) was fitted, freely estimating latent correlations with 95% confidence intervals (95% CI). The results confirmed the scales’ excellent psychometric properties. Importantly, latent factor correlations between MEC10 and mYFAS2.0 (est = 0.783, 95% CI [0.76, 0.80]) supported their discriminant validity. In contrast, the latent correlation of MEC10 and BES (est = 0.86, 95% CI [0.84, 0.87]) exceeded the recommended thresholds, indicating the absence of discriminant validity and suggesting a potential overlap, consistent with previous evidence. In conclusion, MEC10 demonstrates excellent psychometric properties but is more a measure of BED and not FA
Frequency Scaling Model for the Prediction of Total Tropospheric Attenuation Time Series at EHF
No full textA frequency scaling model aiming to predict total tropospheric attenuation time series at EHF is presented. One version of the model [total attenuation frequency scaling (TAFS)] is more accurate but, besides the reference attenuation time series at low frequency, it also requires additional ancillary inputs (e.g., radiometric data and information on the raindrop size distribution); a second version (S-TAFS) is simpler, though at the expenses of a slightly worse performance. Both TAFS and simplified TAFS (S-TAFS) first rely on isolating the attenuation induced by different atmospheric constituents, each of which is separately up-scaled to the target frequency. The two methods are tested against a full year of data collected at Ka-band and Q-band at Politecnico di Milano, Milan, Italy, in the framework of the Alphasat Aldo Paraboni propagation experiment. Results indicate that both methods offer a very good accuracy in scaling the total attenuation from Ka- to Q-bands, both in terms of first-order statistics and of time series. This corroborates the use of TAFS and S-TAFS to predict the total tropospheric attenuation at much higher frequency bands (e.g., the W-band), for which no measurements are currently available, starting from the largely available Ka-band measurements
Psychological Differences Among Healthcare Workers of a Rehabilitation Institute During the COVID-19 Pandemic: A Two-Step Study
Full text linkIntroduction: Healthcare workers facing the threatening COVID-19 can experience severe difficulties. Despite the need to evaluate both the psychological distress and positive protective resources, brief and reliable assessment tools are lacking. Aim: Study 1 aimed at developing a new assessment tool to measure psychological distress and esteem in healthcare workers during the COVID-19 pandemic. Study 2 aimed to explore and compare the psychological reactions of healthcare workers of the COVID-19 and the non-COVID-19 wards. Methods: In Study 1, psychologists created 25 items based on their clinical experience. A preliminary qualitative evaluation selected the best 15 items for the new tool (CPI-HP) assessing the COVID-19 psychological impact with 2 scales: psychological distress and esteem. The CPI-HP was administered to 110 healthcare professionals to study its psychometric properties and the internal structure with exploratory graph analysis and confirmatory factor analysis. Study 2 compared two groups of healthcare professionals of the COVID-19 and non-COVID-19 departments. Results: In Study 1, the CPI-HP showed satisfying psychometric properties, and the two-factor structure was confirmed with good fit indices. In Study 2, the two groups of healthcare workers showed comparable levels of psychological distress and resilient coping, but the COVID-19 group displayed significantly higher esteem and appreciation of the experience. Discussion: All operators showed high psychological distress during the emergency, but the COVID-19 group reported higher resources, probably due to stronger group cohesion and greater esteem, perceived meaning, and own work value. Conclusion: Assessing the psychological distress and resources of healthcare professionals with specific tools is important. Psychological interventions should promote their psychological health
Interventions for psychological health of stroke caregivers: A systematic review
Full text linkBackground: The increasing number of stroke patients (SPs) requires informal caregivers to bear a high burden of responsibilities and heavy (di)stress. Moreover, these issues could lead to the development of serious psychological problems (e.g., depressive and/or anxious) that in turn could give rise to poor health-related quality of life outcomes. However, although the value of psychological interventions has been widely recognized for SPs, the scientific literature lacks an updated synthesis of interventions addressing the psychological health of their caregivers. Aim: The aim of this review is to summarize the interventions for the psychological health of stroke caregivers and provide a resume of literature-based evidence of their efficacy. Method: A literature review from 2005 to date was conducted in three online databases: PubMed, Scopus, and Google Scholar. Eligibility criteria for studies were (A) English language, (B) caregivers and patients aged 18 years or above, (C) SP’s caregiver beneficiating of a specific intervention, and (D) outcome measures addressing depressive and/or anxiety symptomology, quality of life, well-being, or burden. Results: Across the selected 45 studies, substantial differences are observable in three main categories: (a) type of intervention (b) techniques, and (c) operators. Interventions’ advantages and results are discussed. Overall, studies using psychological techniques, such as cognitive-behavioral therapy, coping skill-training, and problem-solving therapy, showed their usefulness and efficacy in reducing the caregivers’ depressive and anxious symptoms, and burden. Interventions led by psychologists and tailored to meet caregivers’ specific needs showed more positive outcomes. Conclusion: This review underlines the usefulness of psychological interventions aimed at reducing the psychological burden, such as anxious and depressive symptomatology, of SPs’ informal caregivers. Hence, psychological interventions for caregivers should be integrated as part of the stroke rehabilitation process to improve informal caregivers’ and patients’ quality of life and well-being
Exploring illness denial of LVAD patients in cardiac rehabilitation and their caregivers: A preliminary study
No full textImplantable left ventricular assist devices (LVADs) are increasingly used for patients with heart failure. Despite this evidence, the psychological processes affecting implanted patients and their caregivers are only marginally studied. While common emotional reactions, such as anxiety and depression already receive attention, very little is known about the course of caregiver strain, illness denial, and their reciprocal relation. This preliminary study aims at exploring these critical topics in a cardiac rehabilitation setting, besides offering indications for future research. A total of 44 LVAD patients and caregivers were administered specific questionnaires at admission and discharge from cardiac rehabilitation. Overall, questionnaires completed at discharge showed a positive improvement in the emotional measures used. However, they also showed a worsening in the illness denial measure. We suggest that the denial process may prepare patients and caregivers in returning home. Moreover, we conclude that studying only the common emotional reactions may limit the understanding of the psychological process adaptation to severe illness
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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