44 research outputs found
Численное моделирование турбулентного течения расплава в двухвалковом кристаллизаторе с щелевым питателем
Разработана трехмерная математическая модель и компьютерная методика по расчету турбулентного течения расплавленного металла в межвалковом канале двухвалкового кристаллизатора при вертикальной подаче металла через щелевой питатель. Компьютерные исследования проведены с использованием численного метода конечных элементов и программы Comsol. По результатам моделирования изучены особенности течения металла в объеме кристаллизатора с учетом краевых эффектов, формирования вихревых структур течения расплава в межвалковом зазоре, распределения характеристик турбулентности в объеме расплава.Розроблено тривимірну математичну модель та комп’ютерну методику з розрахунку турбулентної течії розплавленого металу в міжвалковому каналі двохвалкового кристалізатора при вертикальній подачі металу через щілину. Комп’ютерні дослідження проведено з використанням методу кінцевих елементів у програмі Comsol. За результатами моделювання вивчено особливості руху металу в об’ємі кристалізатора, з урахуванням крайових ефектів, замкнуті вихрові структури течії розплаву в міжвалковому зазорі, розподілення характеристик турбулентності в об’ємі розплаву.The three-dimensional mathematical model and computer technique are developed for computtions of turbulent molten metal flowing in the gap of twin-roll caster at vertical melt feeding through the slit nozzle. The computer modeling is carried out by finite-element method in Comsol. The features of metal flow in the caster including edge effects, closed vortex structures of the flow in the gap between rolls, distribution of turbulence characteristics are studied using the computational results
"Delirium Day": A nationwide point prevalence study of delirium in older hospitalized patients using an easy standardized diagnostic tool
Background: To date, delirium prevalence in adult acute hospital populations has been estimated generally from pooled findings of single-center studies and/or among specific patient populations. Furthermore, the number of participants in these studies has not exceeded a few hundred. To overcome these limitations, we have determined, in a multicenter study, the prevalence of delirium over a single day among a large population of patients admitted to acute and rehabilitation hospital wards in Italy. Methods: This is a point prevalence study (called "Delirium Day") including 1867 older patients (aged 65 years or more) across 108 acute and 12 rehabilitation wards in Italian hospitals. Delirium was assessed on the same day in all patients using the 4AT, a validated and briefly administered tool which does not require training. We also collected data regarding motoric subtypes of delirium, functional and nutritional status, dementia, comorbidity, medications, feeding tubes, peripheral venous and urinary catheters, and physical restraints. Results: The mean sample age was 82.0 ± 7.5 years (58 % female). Overall, 429 patients (22.9 %) had delirium. Hypoactive was the commonest subtype (132/344 patients, 38.5 %), followed by mixed, hyperactive, and nonmotoric delirium. The prevalence was highest in Neurology (28.5 %) and Geriatrics (24.7 %), lowest in Rehabilitation (14.0 %), and intermediate in Orthopedic (20.6 %) and Internal Medicine wards (21.4 %). In a multivariable logistic regression, age (odds ratio [OR] 1.03, 95 % confidence interval [CI] 1.01-1.05), Activities of Daily Living dependence (OR 1.19, 95 % CI 1.12-1.27), dementia (OR 3.25, 95 % CI 2.41-4.38), malnutrition (OR 2.01, 95 % CI 1.29-3.14), and use of antipsychotics (OR 2.03, 95 % CI 1.45-2.82), feeding tubes (OR 2.51, 95 % CI 1.11-5.66), peripheral venous catheters (OR 1.41, 95 % CI 1.06-1.87), urinary catheters (OR 1.73, 95 % CI 1.30-2.29), and physical restraints (OR 1.84, 95 % CI 1.40-2.40) were associated with delirium. Admission to Neurology wards was also associated with delirium (OR 2.00, 95 % CI 1.29-3.14), while admission to other settings was not. Conclusions: Delirium occurred in more than one out of five patients in acute and rehabilitation hospital wards. Prevalence was highest in Neurology and lowest in Rehabilitation divisions. The "Delirium Day" project might become a useful method to assess delirium across hospital settings and a benchmarking platform for future surveys
Prescription appropriateness of anti-diabetes drugs in elderly patients hospitalized in a clinical setting: evidence from the REPOSI Register
Diabetes is an increasing global health burden with the highest prevalence (24.0%) observed in elderly people. Older diabetic adults have a greater risk of hospitalization and several geriatric syndromes than older nondiabetic adults. For these conditions, special care is required in prescribing therapies including anti- diabetes drugs. Aim of this study was to evaluate the appropriateness and the adherence to safety recommendations in the prescriptions of glucose-lowering drugs in hospitalized elderly patients with diabetes. Data for this cross-sectional study were obtained from the REgistro POliterapie-Società Italiana Medicina Interna (REPOSI) that collected clinical information on patients aged ≥ 65 years acutely admitted to Italian internal medicine and geriatric non-intensive care units (ICU) from 2010 up to 2019. Prescription appropriateness was assessed according to the 2019 AGS Beers Criteria and anti-diabetes drug data sheets.Among 5349 patients, 1624 (30.3%) had diagnosis of type 2 diabetes. At admission, 37.7% of diabetic patients received treatment with metformin, 37.3% insulin therapy, 16.4% sulfonylureas, and 11.4% glinides. Surprisingly, only 3.1% of diabetic patients were treated with new classes of anti- diabetes drugs. According to prescription criteria, at admission 15.4% of patients treated with metformin and 2.6% with sulfonylureas received inappropriately these treatments. At discharge, the inappropriateness of metformin therapy decreased (10.2%, P < 0.0001). According to Beers criteria, the inappropriate prescriptions of sulfonylureas raised to 29% both at admission and at discharge. This study shows a poor adherence to current guidelines on diabetes management in hospitalized elderly people with a high prevalence of inappropriate use of sulfonylureas according to the Beers criteria
"Delirium Day": A nationwide point prevalence study of delirium in older hospitalized patients using an easy standardized diagnostic tool
Background: To date, delirium prevalence in adult acute hospital populations has been estimated generally from pooled findings of single-center studies and/or among specific patient populations. Furthermore, the number of participants in these studies has not exceeded a few hundred. To overcome these limitations, we have determined, in a multicenter study, the prevalence of delirium over a single day among a large population of patients admitted to acute and rehabilitation hospital wards in Italy. Methods: This is a point prevalence study (called "Delirium Day") including 1867 older patients (aged 65 years or more) across 108 acute and 12 rehabilitation wards in Italian hospitals. Delirium was assessed on the same day in all patients using the 4AT, a validated and briefly administered tool which does not require training. We also collected data regarding motoric subtypes of delirium, functional and nutritional status, dementia, comorbidity, medications, feeding tubes, peripheral venous and urinary catheters, and physical restraints. Results: The mean sample age was 82.0 \ub1 7.5 years (58 % female). Overall, 429 patients (22.9 %) had delirium. Hypoactive was the commonest subtype (132/344 patients, 38.5 %), followed by mixed, hyperactive, and nonmotoric delirium. The prevalence was highest in Neurology (28.5 %) and Geriatrics (24.7 %), lowest in Rehabilitation (14.0 %), and intermediate in Orthopedic (20.6 %) and Internal Medicine wards (21.4 %). In a multivariable logistic regression, age (odds ratio [OR] 1.03, 95 % confidence interval [CI] 1.01-1.05), Activities of Daily Living dependence (OR 1.19, 95 % CI 1.12-1.27), dementia (OR 3.25, 95 % CI 2.41-4.38), malnutrition (OR 2.01, 95 % CI 1.29-3.14), and use of antipsychotics (OR 2.03, 95 % CI 1.45-2.82), feeding tubes (OR 2.51, 95 % CI 1.11-5.66), peripheral venous catheters (OR 1.41, 95 % CI 1.06-1.87), urinary catheters (OR 1.73, 95 % CI 1.30-2.29), and physical restraints (OR 1.84, 95 % CI 1.40-2.40) were associated with delirium. Admission to Neurology wards was also associated with delirium (OR 2.00, 95 % CI 1.29-3.14), while admission to other settings was not. Conclusions: Delirium occurred in more than one out of five patients in acute and rehabilitation hospital wards. Prevalence was highest in Neurology and lowest in Rehabilitation divisions. The "Delirium Day" project might become a useful method to assess delirium across hospital settings and a benchmarking platform for future surveys
AGILE detection of extreme γ -ray activity from the blazar PKS 1510-089 during March 2009: Multifrequency analysis
We report on the extreme gamma-ray activity from the FSRQ PKS 1510-089
observed by AGILE in March 2009. In the same period a radio-to-optical
monitoring of the source was provided by the GASP-WEBT and REM. Moreover,
several Swift ToO observations were triggered, adding important information on
the source behaviour from optical/UV to hard X-rays. We paid particular
attention to the calibration of the Swift/UVOT data to make it suitable to the
blazars spectra. Simultaneous observations from radio to gamma rays allowed us
to study in detail the correlation among the emission variability at different
frequencies and to investigate the mechanisms at work. In the period 9-30 March
2009, AGILE detected an average gamma-ray flux of (311+/-21)x10^-8 ph cm^-2
s^-1 for E>100 MeV, and a peak level of (702+/-131)x10^-8 ph cm^-2 s^-1 on
daily integration. The gamma-ray activity occurred during a period of
increasing activity from near-IR to UV, with a flaring episode detected on
26-27 March 2009, suggesting that a single mechanism is responsible for the
flux enhancement observed from near-IR to UV. By contrast, Swift/XRT
observations seem to show no clear correlation of the X-ray fluxes with the
optical and gamma-ray ones. However, the X-ray observations show a harder
photon index (1.3-1.6) with respect to most FSRQs and a hint of
harder-when-brighter behaviour, indicating the possible presence of a second
emission component at soft X-ray energies. Moreover, the broad band spectrum
from radio-to-UV confirmed the evidence of thermal features in the optical/UV
spectrum of PKS 1510-089 also during high gamma-ray state. On the other hand,
during 25-26 March 2009 a flat spectrum in the optical/UV energy band was
observed, suggesting an important contribution of the synchrotron emission in
this part of the spectrum during the brightest gamma-ray flare, therefore a
significant shift of the synchrotron peak
AGILE detection of a rapid γ-ray flare from the blazar PKS 1510-089 during the GASP-WEBT monitoring
We report the detection by the AGILE satellite of a rapid gamma-ray flare
from the powerful gamma-ray quasar PKS 1510-089, during a pointing centered on
the Galactic Center region from 1 March to 30 March 2008. This source has been
continuosly monitored in the radio-to-optical bands by the GLAST-AGILE Support
Program (GASP) of the Whole Earth Blazar Telescope (WEBT). Moreover, the
gamma-ray flaring episode triggered three ToO observations by the Swift
satellite in three consecutive days, starting from 20 March 2008. In the period
1-16 March 2008, AGILE detected gamma-ray emission from PKS 1510-089 at a
significance level of 6.2-sigma with an average flux over the entire period of
(84 +/- 17) x 10^{-8} photons cm^{-2} s^{-1} for photon energies above 100 MeV.
After a predefined satellite re-pointing, between 17 and 21 March 2008, AGILE
detected the source at a significance level of 7.3-sigma, with an average flux
(E > 100 MeV) of (134 +/- 29) x 10^{-8} photons cm^{-2} s^{-1} and a peak level
of (281 +/- 68) x 10^{-8} photons cm^{-2} s^{-1} with daily integration. During
the observing period January-April 2008, the source also showed an intense and
variable optical activity, with several flaring episodes and a significant
increase of the flux was observed at millimetric frequencies. Moreover, in the
X-ray band the Swift/XRT observations seem to show an harder-when-brighter
behaviour of the source spectrum. The spectral energy distribution of mid-March
2008 is modelled with a homogeneous one-zone synchrotron self Compton emission
plus contributions from inverse Compton scattering of external photons from
both the accretion disc and the broad line region. Indeed, some features in the
optical-UV spectrum seem to indicate the presence of Seyfert-like components,
such as the little blue bump and the big blue bump
Environmental Management Practices for the Textile Sector
Part 5: Sustainability and Production ManagementInternational audienceEnvironmental sustainability is gaining more and more relevance for textile companies. However, there are often problems with application, even in the most committed companies. In this paper, an empirical typology of Italian textile firms that discern the patterns of practices used in response to environmental issues and concerns that affect such industry is proposed. The resulting typology is composed by three types: Best practice, Good practice and Bad practice. Each type is then characterised in terms of firm’s characteristics and perceived environmental competitiveness benefits. The discussion of some open issues deriving from the empirical analysis precedes the final conclusion
Post-pandemic reconfiguration from global to domestic and regional value chains: the role of industrial policies
The COVID-19 pandemic is expected to trigger a reconfiguration of global
value chains according to four alternative trajectories: reshoring, regionalization,
replication and diversification. This paper focuses on the first two scenarios.
On the basis of a review of the extant reshoring literature and policies implemented
in several major developed and emerging economies, we present a comprehensive
framework to classify and analyse the evolution of such policies before and after
the pandemic. The paper develops some policy recommendations suggesting that
reshoring policies need to be supported by and combined with industrial policies
enforcing the competitiveness and sustainability of production systems