51 research outputs found
Analisi numerica del procedimento di Base Bleed applicato ad un autoveicolo.
Viene studiato numericamente il soffiaggio dalla base di un modello semplificato di veicolo. Il software utilizzato è costituito dal pacchetto Fluent, mentre il modello riproduce una vettura coupè semplificata con la zona posteriore di tipo fastback.
Si cerca di individuare quali siano le strategie di soffiaggio più efficaci per aumentare il recupero di pressione sulla base e quali siano gli effetti dei principali parametri a disposizione.
Si individuano due metodologie di azione per il soffiaggio. Nella prima si cerca di "spingere" i vortici principali della scia più a valle, nella seconda invece si agisce sulla loro intensità, diffondendoli con della vorticità di segno contrario opportunamente introdotta.
Si realizzano le due tecniche implementando tre differenti tipologie di sbocchi sulla base.
Per limitare il numero di variabili si soffia solo perpendicolarmente alla superficie del modello da uscite rettangolari, imponendo un profilo di velocità in uscita costante. La posizione delle uscite come anche la loro estensione viene variata.
Non si prende volutamente in considerazione il problema della implementazione tecnica del soffiaggio sull'autoveicolo
Cross-cultural solutions volunteer handbook
Alexa worked with Cross-Cultural Solutions to design and create a handbook that could prepare volunteers for their experience abroad. By using her personal experience abroad at El Pueblito, an orphanage in Cartago, Costa Rica, Alexa was able to compile resources and information that would be useful for a first-time volunteer to make the most out of their experience and to make sure they are prepared for working with the children. The final product is an interactive PDF handbook and an accompanying classroom activity bank on Pinterest that can be accessed digitally by CCS volunteers worldwide
The return home : experiences of deterritorialization in post-Pinochet Chilean literature
Ph.D. University of Kansas, Spanish and Portuguese 2002In response to the experiences of exile and the return, the subsequent preoccupation with a sense of belonging, the blurring of the traditional understanding of borders triggered by a permanent sense of displacement, and the quest for assimilation within the boundaries of the restored motherland have become some of the most dominant themes of post-Pinochet Chilean literature. In chapter one, the characters in Ariel Dorfman's play La muerte y la doncella (1991) illustrate returnees, struggles to establish a sense of place so that they may recover their original imagined community and highlight the breakdown of communication due to the effects of dislocation. But when an exile experiences separation from home and lives in the context of another place, the imagined community representing the original home and the new one begin to mix and merge. Seen in Heading South, Looking North (1997), Dorfman reinterprets what this original community represents and demonstrates acceptance of an ironic conception of nostalgia that celebrates the fragmentation of a place balanced in-between. Antonio Skármeta evokes the memory of home and exile in the second chapter as two distinct, independent locations. Skármeta remembers the place called home in the play Ardiente paciencia (1983) and the place of exile in the novel Match Ball (1989) as home and host communities. In this manna, Skármeta replaces nostalgia for home and the expression of national traditions with the exposition of transnational migrants, socio-political refugees, and international frontier conditions. The third chapter looks at a younger generation of post-Pinochet writers, represented by author Alberto Fuguet, who inherited the experience of exile and the return as “borrowed” conditions, and who experienced the return to Chile not as a process of re-discovery but rather as new discovery. Fuguet's novel Mala onda (1991) and short story collection Por favor, rebobinar (1994), express the emergence of young Chileans into deterritorialized worlds where sentiments of dislocation caused by the blurring of the definitions of home and location represent a society existing in a precarious and orphaned state
Aging and Asbestosis of Parenchyma and/or Pleura
Ispitivan je utjecaj dobi na plućne funkcije u odnosu na sijelo azbestnih promjena na plućima i/ili pleuri. Pregledano je 97 muškaraca s profesionalnom azbestozom i 100 ispitanika kontrolne skupine. Uzeta je osobna i radna anamneza, načinjen klinički pregled, standardizirane radiologijske snimke pluæa i izmjerene ventilacijske funkcije VC, FVC, FEV1, FEV1/VC, FEV1/FVC.
Fibrozu pluća imalo je 31 %, fibrozu pleure 34 %, a miješanu fibrozu 35 % ispitanika. Svi oboljeli imali su dispneju, 2/3 samo u naporu, a 1/3 i u mirovanju. U kontrolnoj skupini bila je samo 1/3 dispnoiènih, i to samo u naporu (p<0,001). Ventilacijske funkcije bile su značajno niže u oboljelih, nego u kontrole (p<0,01). Klinički značajne restriktivne i opstruktivne promjene zabilježene su u oboljelih od miješane i azbestoze pleure.
Veće oštećenje ventilacijske funkcije imali su oboljeli s miješanom i s azbestozom pleure nego s azbestozom pluća. U oboljelih s azbestnim promjenama na pleuri nije bilo moguće razlučiti što više doprinosi opadanju plućne funkcije, porast dobi ili duljine izloženosti.This study included 97 subjects with parenchymal and/or pleural asbestosis and 100 controls. Data analysis included medical and work histories, X-ray, clinical examination, and the measurement/calculation of ventilatory lung functions VC, FVC, FEV1, FEV1/VC, and FEV1/FVC.Of 97 subjects with asbestosis, 30 (31 %) were diagnosed parenchymal fibrosis, 33 (34 %) pleural fibrosis, and 34 (35 %) parenchymal and pleural fibrosis combined. These subgroups did not differ in smoking habit.All subjects with asbestosis showed symptoms of dyspnoea; two thirds showed dyspnoea on exercise and one third at rest as well. In contrast, only one third of controls showed dyspnoea on exercise only.All ventilatory lung functions were lower in subjects with asbestosis than in controls (P0.05). Slight, yet clinically significant drops in ventilatory function were observed in subjects with pleural (VC 79.73 %; FVC 75.09 %; and FEV1 78.52 %) and combined asbestosis (VC 78.21 %; FVC 75.01 %; and FEV1 77.50 %), while ventilatory changes in subjects with parenchymal asbestosis were clinically significant only for FVC (79.60 %).It was not possible to discriminate between the effects of age and exposure duration in subjects with pleural and combined asbestosis
Dehydration process influences the phenolic profile, antioxidant and antimicrobial properties of Galium aparine L.
Galium aparine L. is a very disseminated plant in temperate zones, commonly known as clivers or bedstraw,
belonging to the Rubiaceae family and it is traditionally used for its medicinal applications. In this study, G.
aparine hydromethanolic extracts and infusions were prepared from air-dried and freeze-dried samples in order
to assess their phenolic profile, antioxidant, antimicrobial, and cytotoxic properties. All the studied extracts
revealed a similar phenolic profile, but the hydromethanolic extract obtained from the freeze-dried sample
presented the highest concentration of phenolic compounds, followed by the respective infusion and the airdried
sample hydromethanolic extract. The major compound detected in the extracts was 5-O-caffeoylquinic acid
(from 145 to 163 mg/g extract). Regarding the bioactivity, in general, the extracts presenting higher phenolic
concentrations also revealed enhanced bioactive properties. The EC50 values obtained in the antioxidant activity
assays ranged from 13.5 to 884 μg/mL, with the freeze-dried sample hydromethanolic extract presenting the
highest activity (13.5–555 μg/mL). Similar conclusions could be made in terms of antimicrobial properties, with
this extract showing the lowest MIC (1.85–15 mg/mL), MBC (3.75–7.5 mg/mL), and MFC (3.75–20 mg/mL)
values. None of the extracts revealed cytotoxicity. The results obtained in this study suggested that G. aparine
extracts can be a good source of phenolic compounds with antioxidant and antimicrobial properties.The authors are grateful to the Foundation for Science and
Technology (FCT, Portugal) and FEDER under Programme PT2020 for
financial support to CIMO (UID/AGR/00690/2013); to FCT for L.
Barros research contract; to FCT for the grant attributed to C. Pereira
(SFRH/BPD/122650/2016) through the Programa Operacional Capital
Humano (POCH) supported by the European Social Fund and National
Funds of MCTES (Ministério da Ciência, Tecnologia, e Ensino Superior);
and to FEDER-Interreg España-Portugal programme for financial support
through the project 0377_Iberphenol_6_E. The authors are also
grateful to the Serbian Ministry of Education, Science and
Technological Development, grant number 173032 for financial support.info:eu-repo/semantics/publishedVersio
Comparative analysis of photometric variability of TT ARI in the years 1994-1995 and 2001, 2004
We present the results of photometric observations of a bright cataclysmic variable TT Ari with an orbital period of 0. 13755 days. CCD observations were carried out with the Russian-Turkish RTT 150 telescope in 2001 and 2004 (13 nights). Multi-color photoelectric observations of the system were obtained with the Zeiss 600 telescope of SAO RAS in 1994-1995 (6 nights). In 1994-1995, the photometric period of the system was smaller than the orbital one (0. d132 and 0. d134), whereas it exceeded the latter (0. d150 and 0. d148) in 2001, 2004. An additional period exceeding the orbital one (0. d144) is detected in 1995 modulations. We interpret it as indicating the elliptic disc precession in the direction of the orbital motion. In 1994, the variability in colors shows periods close to the orbital one (0. d136, b-v), as well as to the period indicating the elliptic disk precession (0. d146, w-b). We confirm that during the epochs characterized by photometric periods shorter than the orbital one, the quasi-periodic variability of TT Ari at time scales about 20 min is stronger than during epochs with long photometric periods. In general, the variability of the system can be described as a "red" noise with increased amplitudes of modulations at characteristic time scales of 10-40 min. © 2013 Pleiades Publishing, Ltd
Subjective Symptoms in Magnetic Resonance Imaging Personnel: A Multi-Center Study in Italy
Introduction: Magnetic Resonance Imaging (MRI) personnel have significant exposure to static and low-frequency time-varying magnetic fields. In these workers an increased prevalence of different subjective symptoms has been observed. The aim of our study was to investigate the prevalence of non-specific subjective symptoms and of “core symptoms” in a group of MRI personnel working in different centers in Italy, and of possible relationships with personal and occupational characteristics.Methods: The occurrence of 11 subjective symptoms was evaluated using a specific questionnaire with 240 subjects working in 6 different Italian hospitals and research centers, 177 MRI health care and research personnel and 63 unexposed subjects employed in the same departments. Exposure was subjectively investigated according to the type of MRI scanner (≤1.5 vs. ≥3 T) and to the number of MRI procedures attended and/or performed by the personnel, even if no information on how frequently the personnel entered the scanner room was collected. The possible associations among symptoms and estimated EMF exposure, the main characteristics of the population, and job stress perception were analyzed.Results: Eighty-six percent of the personnel reported at least one symptom; drowsiness, headache, and sleep disorders were the most frequent. The total number of symptoms did not differ between exposed persons and controls. Considering the total number of annual MRI procedures reported by the personnel, no significant associations were found nor with the total number of symptoms, nor with “core symptoms.” Only subjects complaining of drowsiness also reported a significantly higher mean annual number of MRI procedures with ≤ 1.5 T scanners when compared with exposed subjects without drowsiness. In a multivariate model, subjects with a high level of perceived stress complained of more symptoms (p = 0.0002).Conclusions: Our study did not show any association between the occurrence of reversible subjective symptoms, including the more specific “core symptoms,” and the occupational exposure of MRI personnel to static and low-frequency time-varying magnetic fields. On the other hand, the role played by occupational stress appears to be not negligible. In further research in this field, measurements of EMF exposure should be considered
Predicting stroke in Asian patients with atrial fibrillation using machine learning: A report from the KERALA-AF registry, with external validation in the APHRS-AF registry.
Atrial fibrillation (AF) is a significant risk factor for stroke. Based on the higher stroke associated with AF in the South Asian population, we constructed a one-year stroke prediction model using machine learning (ML) methods in KERALA-AF South Asian cohort. External validation was performed in the prospective APHRS-AF registry. We studied 2101 patients and 83 were to patients with stroke in KERALA-AF registry. The random forest showed the best predictive performance in the internal validation with receiver operator characteristic curve (AUC) and G-mean of 0.821 and 0.427, respectively. In the external validation, the light gradient boosting machine showed the best predictive performance with AUC and G-mean of 0.670 and 0.083, respectively. We report the first demonstration of ML's applicability in an Indian prospective cohort, although the more modest prediction on external validation in a separate multinational Asian registry suggests the need for ethnic-specific ML models
A search for periodic and quasi-periodic photometric behavior in the cataclysmic variable TT arietis
Observations of TT Ari obtained at 11 observatories (campaign TT Ari-94) during 258 hr were carried out to study optical variability on timescales from minutes to weeks. The best-fit primary photometric period determined from 16 nights of data obtained at the Dushak-Eregdag station of the Odessa State University is P = 0d.133160 ± 0d.000004 with a mean amplitude of 0.0513 ± 0.0008 mag. This new primary photometric period is larger than that obtained during the TT Ari-88 campaign and is well outside the range of estimates published since 1961. Contrary to previous findings, the "5-7 hr" secondary photometric period is not seen. Our observations do show evidence for periods of 2d.916 and 0d.3040 with amplitudes of 43 and 25 mmag, respectively. The beat period between the spectroscopic and photometric periods is not seen. No coherent oscillations in the range f = 10-2500 cycles day-1 are found. The highest peaks in the power spectrum cover the wide range of 24-139 cycles day-1. In the mean periodogram, the highest peak corresponds to 21 and 30 minutes for the largest sets of observations, i.e., those obtained at Odessa and Krakow Universities, respectively. In the instrumental B system, variations with an amplitude exceeding 0.011 mag occur 8 times (from 33 runs) at 24 minutes. We conclude that quasi-periodic variations occur at a few preferred timescales rather than at a relatively stable period with a secular decrease. In the frequency range 90-900 cycles day-1, the power spectrum obeys a power law with a slope ranging from γ = 1.3 to 2.6 for different runs
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