Search results for " function"
showing 10 items of 9395 documents
A Check of Water Drop Impact Effects on Surface Soil Saturated Hydraulic Conductivity
2020
The post-tillage dynamics of the surface soil saturated hydraulic conductivity, Ks, was studied at the Masse experimental station (central Italy, silty-clay-loam soil). A sequence of experiments was performed by rainfall simulation on two replicated micro-plots (width 1 m, length 0.92 m, slope 16%) established on bare soil. Each high-intensity rainfall simulation was preceded by a low-intensity wetting phase. The soil water content, w, was measured before wetting and both before and after simulation. Runoff was measured at 5 min intervals. The infiltration rate was calculated as the difference between rainfall intensity and runoff rate. Finally, Ks was assumed to be equal to the infiltratio…
Soil water erosion on Mediterranean vineyards: A review
2016
Soil water erosion on cultivated lands represents a severe threat to soil resources in the world, and especially in Mediterranean areas, due to their topographic, edaphic and climatic conditions. Among the cultivated lands, vineyards deserve a particular attention because, aside representing one of the most important crops in terms of income and employment, they also have proven to be the form of agricultural use that causes one of the highest soil losses. Although the topic of soil water erosion on vineyards has been studied, it still raises uncertainties, due to the high variability of procedures for data acquisition, which consists into different scales of analysis and measurement method…
Strict blood-pressure control and progression of renal failure in children
2009
PubMedID: 19846849 BACKGROUND: Although inhibition of the renin-angiotensin system delays the progression of renal failure in adults with chronic kidney disease, the blood-pressure target for optimal renal protection is controversial. We assessed the long-term renoprotective effect of intensified blood-pressure control among children who were receiving a fixed high dose of an angiotensin-converting- enzyme (ACE) inhibitor. METHODS: After a 6-month run-in period, 385 children, 3 to 18 years of age, with chronic kidney disease (glomerular filtration rate of 15 to 80 ml per minute per 1.73 m2 of body-surface area) received ramipril at a dose of 6 mg per square meter of bodysurface area per day…
Antihypertensive and cardiovascular effects of combined blockade of renin-angiotensin system with ACE inhibitor and angiotensin II type 1 receptor bl…
2006
BACKGROUND.: In this study the effects of 24 weeks losartan and ramipril treatment, both alone and in combination, on blood pressure and left ventricular mass (LVM) and function, have been evaluated in hypertensives. METHODS.: 57 hypertensives with stage 1 and 2 essential hypertension were included. After 4 weeks run in, a randomized double-blind, 3 arm, double dummy, independent trial was used. All patients were randomly allocated to 3 treatment arms consisting of losartan (50 mg/daily), ramipril (5 mg/daily), and combined (losartan 50 mg/ramipril 5 mg/daily) for 24 weeks. LVM, LVM/h(2.7) and other echocardiographic measurements, BUN, creatinine and clearance and potassium were determined …
Renal outcomes and blood pressure patterns in diabetic and nondiabetic individuals at high cardiovascular risk
2021
Background Diabetes and hypertension are risk factors for renal and cardiovascular outcomes. Data on the association of achieved blood pressure (BP) with renal outcomes in patients with and without diabetes are sparse. We investigated the association of achieved SBP, DBP with renal outcomes and urinary albumin excretion (UAE) in people with vascular disease. Methods In this pooled analysis, we assessed renal outcome data from high-risk patients aged 55 years or older with a history of cardiovascular disease, 70% of whom had hypertension, randomized to The Ongoing Telmisartan Alone and in Combination with Ramipril Global Endpoint Trial and to Telmisartan Randomized Assessment Study in ACE In…
Statins and peripheral arterial disease: effects on claudication, disease progression, and prevention of cardiovascular events.
2006
Peripheral arterial disease (PAD) of the lower limbs is the third most important site of atherosclerotic disease alongside coronary heart disease (CHD) and cerebrovascular disease (CVD). Best medical treatment is beneficial even in patients who eventually need invasive treatment, as the safety, immediate success, and durability of intervention is greatly improved in patients who adhere to best medical treatment. In recent years, a number of studies have suggested that the ACE-inhibitor ramipril and different statins, together with antiplatelet drugs, reduce cardiovascular morbidity and mortality in PAD. Patients with PAD are really a category of patients with a very high cardiovascular risk…
Bayesian hierarchical nonlinear modelling of intra-abdominal volume during pneumoperitoneum for laparoscopic surgery
2021
Laparoscopy is an operation carried out in the abdomen or pelvis through small incisions with external visual control by a camera. This technique needs the abdomen to be insufflated with carbon dioxide to obtain a working space for surgical instruments' manipulation. Identifying the critical point at which insufflation should be limited is crucial to maximizing surgical working space and minimizing injurious effects. Bayesian nonlinear growth mixed-effects models are applied to data coming from a repeated measures design. This study allows to assess the relationship between the insufflation pressure and the intra--abdominal volume.
Thickness Dependence of Random Field Distribution in Thin Films Made of Disordered Ferroelectrics
2005
Abstract We present the calculation of first moment E 0 and variance ΔE of distribution function of random fields in a ferroelectric of finite size. Specific calculations have been performed for the case of slab-shaped ferroelectric thin film. We have shown that E 0 and ΔE can be expressed through the integrals from first and second degree of Green's function of ferroelectric in k-space. To obtain the Green's function, we solve the differential equation minimizing Landau free energy of a ferroelectric with respect to the boundary conditions on its surfaces. We show that both E 0 and ΔE depend on film thickness L.
Information Functionals and the Notion of (Un)Certainty: Random Matrix Theory - Inspired Case
2007
Information functionals allow one to quantify the degree of randomness of a given probability distribution, either absolutely (through min/max entropy principles) or relative to a prescribed reference one. Our primary aim is to analyze the “minimum information” assumption, which is a classic concept (R. Balian, 1968) in the random matrix theory. We put special emphasis on generic level (eigenvalue) spacing distributions and the degree of their randomness, or alternatively — information/organization deficit.
Growth, percolation, and correlations in disordered fiber networks
1997
This paper studies growth, percolation, and correlations in disordered fiber networks. We start by introducing a 2D continuum deposition model with effective fiber-fiber interactions represented by a parameter $p$ which controls the degree of clustering. For $p=1$, the deposited network is uniformly random, while for $p=0$ only a single connected cluster can grow. For $p=0$, we first derive the growth law for the average size of the cluster as well as a formula for its mass density profile. For $p>0$, we carry out extensive simulations on fibers, and also needles and disks to study the dependence of the percolation threshold on $p$. We also derive a mean-field theory for the threshold ne…