269 research outputs found
L'importanza delle vegetazioni relitte e delle siepi nell\'agroecosistema della Pianura Padana e nella ricostruzione dinamica della vegetazione
ItDi fronte alla continua degradazione dell’ambiente e all’esigenza di ricercare nuovi equilibri tra ambiente ed agricoltura, acquista sempre maggiore importanza la conoscenza dei relitti di vegetazione forestale e delle siepi che costituiscono attualmente un punto di aggregazione di specie relitte, sparse nel territorio. Alle situazioni relitte ed alle siepi si lega tutta la problematica non solo vegetale ma anche animale che deve essere tenuta presente nella ipotizzazione di nuovi agroecosistemi a basso impatto ambientale.EnBecause of continuos environment degradation and in view of the necessity of searching new equilibria between environment and agriculture, it becames more and more important to have knowledge of forest relicts and hedges, that represent, at present, a point of aggregation for the relict species spread in the area. Relict vegetation and hedges are in tight connection with all of those problems regarding plants and animals, which must be kept in mind in planning new agro-ecosystems having low envirommental impact
Healthy Eating, Physical Activity, and Sleep Hygiene (HEPAS) as the Winning Triad for Sustaining Physical and Mental Health in Patients at Risk for or with Neuropsychiatric Disorders: Considerations for Clinical Practice
Neuropsychiatric disorders stem from gene-environment interaction and their development can be, at least in some cases, prevented by the adoption of healthy and protective lifestyles. Once full blown, neuropsychiatric disorders are prevalent conditions that patients live with a great burden of disability. Indeed, the determinants that increase the affliction of neuropsychiatric disorders are various, with unhealthy lifestyles providing a significant contribution in the interplay between genetic, epigenetic, and environmental factors that ultimately represent the pathophysiological basis of these impairing conditions. On one hand, the adoption of Healthy Eating education, Physical Activity programs, and Sleep hygiene promotion (HEPAS) has the potential to become one of the most suitable interventions to reduce the risk to develop neuropsychiatric disorders, while, on the other hand, its integration with pharmacological and psychological therapies seems to be essential in the overall management of neuropsychiatric disorders in order to reduce the disability and improve the quality of life of affected patients. We present an overview of the current evidence in relation to HEPAS components in the prevention and management of neuropsychiatric disorders and provide suggestions for clinical practice
Left atrial conduit flow rate at baseline and during exercise: an index of impaired relaxation in HFpEF patients
Aims
In healthy subjects, adrenergic stimulation augments left ventricular (LV) long-axis shortening and lengthening, and increases left atrial (LA) to LV intracavitary pressure gradients in early diastole. Lower increments are observed in patients with heart failure with preserved ejection fraction (HFpEF). We hypothesized that exercise in HFpEF would further impair passive LV filling in early-mid diastole, during conduit flow from pulmonary veins.
Methods and results
Twenty HFpEF patients (67.8 ± 9.8 years; 11 women), diagnosed using 2007 ESC recommendations, underwent ramped semi-supine bicycle exercise to submaximal target heart rate (∼100 bpm) or symptoms. Seventeen asymptomatic subjects (64.3 ± 8.9 years; 7 women) were controls. Simultaneous LA and LV volumes were measured from pyramidal 3D-echocardiographic full-volume datasets acquired from an apical window at baseline and during stress, together with brachial arterial pressure. LA conduit flow was computed from the increase in LV volume from its minimum at end-systole to the last frame before atrial contraction (onset of the P wave), minus the reduction in LA volume during the same time interval; the difference was integrated and expressed as average flow rate, according to a published formula. The slope of single-beat preload recruitable stroke work (PRSW) quantified LV inotropic state. 3D LV torsion (rotation of the apex minus rotation of the base divided by LV length) was also measurable, both at rest and during stress, in 10 HFpEF patients and 4 controls. There were divergent responses in conduit flow rate, which increased by 40% during exercise in controls (+17.8 ± 37.3 mL/s) but decreased by 18% in patients with HFpEF (−9.6 ± 42.3 mL/s) (P = 0.046), along with congruent changes (+1.77 ± 1.13°/cm vs. −1.94 ± 2.73°/cm) in apical torsion (P = 0.032). Increments of conduit flow rate and apical torsion during stress correlated with changes in PRSW slope (P = 0.003 and P = 0.006, respectively).
Conclusions
In HFpEF, conduit flow rate decreases when diastolic dysfunction develops during exercise, in parallel with changes in LV inotropic state and torsion, contributing to impaired stroke volume reserve. Conduit flow is measurable using 3D-echocardiographic full-volume atrio-ventricular datasets, and as a marker of LV relaxation can contribute to the diagnosis of HFpEF
Influence of body variables in the development of metabolic syndrome : A long term follow-up study
Objectives. The body variable associated with the diagnosis of Metabolic Syndrome (MetS) is an elevated waist circumference (WC), although a number of other variables have been suggested. Among these, an elevated waist-to-height ratio (WHtR), ie a value higher than 0.5, that may identify abnormality, independently from height. An elevated WHtR provided the best correlation with MetS in a prior study in a large Italian population. In order to assess the validity of this conclusion, a long-term follow-up study re-examined this population, also in order to detect possible associations with cardiovascular (CV) risk. Methods and Results. 1,071 subjects with a complete follow-up of over 6 years were evaluated with a comparative assessment of the three anthropometric variables, namely WHtR, WC and body mass index (BMI). WHtR 65 0.5 had the highest sensitivity for the identification of MetS, both in males and females (94.1% and 86.7% respectively). WHtR was of reduced specificity, occurring, yet less frequently (17.7% in males and 30% in females), in patients without MetS. By contrast, enlarged WC occurred with a lower frequency in male patients who developed MetS (30.2%) whereas in females, frequency was higher than in males (69.3%). Finally, a BMI 65 25 kg/m2 had intermediate sensitivity and specificity regardless of gender. WC showed the highest odds ratio (2.62, 95%CI: 1.18-5.78) for the prediction of CV occurrence. Conclusion. The present study confirms WHtR as an excellent screening tool in identifying MetS carriers, but, different from reports in other countries, it shows a lower specificity in our population
Biochemical and morphological modifications in rabbit Achilles tendon during maturation and ageing
Upgraded Pulsating Heat Pipe Only For Space (U-Phos): Results of the 22nd Rexus Sounding Rocket Campaign
A large tube may still behave, to a certain extent, as a capillary in a micro-gravity environment. This very basic concept is here applied to a two-phase passive heat transfer devices in order to obtain a new family of hybrid wickless heat pipes. Indeed, a Loop Thermosyphon, which usually consists of a large tube, closed end to end in a loop, evacuated and partially filled with a working fluid and intrinsically gravity assisted, may become a capillary tube in space condition and turn its thermo-fluidic behavior into a so called Pulsating Heat Pipe (PHP), or better, a Space Pulsating Heat Pipe (SPHP). Since the objective of the present work is to experimentally demonstrate the feasibility of such a hybrid device, a SPHP has been designed, built, instrumented and tested both on ground and microgravity conditions on the 22nd ESA REXUS Sounding Rocket Campaign. Ground tests demonstrate that the device effectively work as a gravity assisted loop thermosyphon, whether the sounding rocket data clearly reveal a change in the thermal hydraulic behavior very similar to the PHP. Since a microgravity period of approximately 120s is not sufficient to reach a pseudo steady state regime, further investigation on a longer term weightless condition is mandatory
U-PHOS Project: Development of a Large Diameter Pulsating Heat Pipe Experiment on board REXUS 22
U-PHOS Project aims to analyse and characterise the behaviour of a large diameter Pulsating Heat Pipe (PHP) on board REXUS 22 sounding rocket. A PHP is a passive thermal control device consisting of a serpentine capillary tube, evacuated, partially filled with a working fluid and finally sealed. In this configuration, the liquid and vapour phases are randomly distributed in the form of liquid slugs and vapour plugs. The heat is efficiently transported by means of the self-sustained oscillatory fluid motion driven by the phase change phenomena. On ground conditions, a small diameter is required in order to obtain a confined slug flow regime. In milli-gravity conditions, buoyancy forces become less intense and the PHP diameter may be increased still maintaining the slug/plug flow configuration typical of the PHP operation. Consequently, the PHP heat power capability may be increased too. U-PHOS aims at proving that a Large Diameter PHP effectively works in milli-g conditions by characterizing its thermal response during a sounding rocket flight. The actual PHP tube is made of aluminum (3 mm inner diameter, filled with FC-72), heated at the evaporator by a compact electrical resistance, cooled at the condenser by a Phase Change Material (PCM) embedded in a metallic foam. The tube wall temperatures are recorded by means of Fibre Bragg Grating (FBG) sensors; the local fluid pressure is acquired by means of a pressure transducer. The present work intends to report the actual status of the project, focusing in particular on the experiment improvements with respect to the previous campaign
Plerixafor and G-CSF combination mobilizes hematopoietic stem and progenitors cells with a distinct transcriptional profile and a reduced in vivo homing capacity compared to plerixafor alone
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