1,416 research outputs found
Symmetries of Helmholtz forms and globally variational dynamical forms
Invariance properties of classes in the variational sequence suggested to
Krupka et al. the idea that there should exist a close correspondence between
the notions of variationality of a differential form and invariance of its
exterior derivative. It was shown by them that the invariance of a closed
Helmholtz form of a dynamical form is equivalent with local variationality of
the Lie derivative of the dynamical form, so that the latter is locally the
Euler--Lagrange form of a Lagrangian. We show that the corresponding local
system of Euler--Lagrange forms is variationally equivalent to a global
Euler--Lagrange form.Comment: Presented at QTS7 - Quantum Theory and Symmetries VII, Prague
7-13/08/201
The Prolongation Problem for the Heavenly Equation
We provide an exact regular solution of an operator system arising as the
prolongation structure associated with the heavenly equation. This solution is
expressed in terms of operator Bessel coefficients.Comment: 9 pages, Proc. SIGRAV Conference (Bari 1998
Integrable nonlinear field equations and loop algebra structures
We apply the (direct and inverse) prolongation method to a couple of
nonlinear Schr{\"o}dinger equations. These are taken as a laboratory field
model for analyzing the existence of a connection between the integrability
property and loop algebras. Exploiting a realization of the Kac-Moody type of
the incomplete prolongation algebra associated with the system under
consideration, we develop a procedure with allows us to generate a new class of
integrable nonlinear field equations containing the original ones as a special
case.Comment: 13 pages, latex, no figures
Musculoskeletal Physical Therapy During the COVID-19 Pandemic: Is Telerehabilitation the Answer?
The coronavirus disease 2019 (COVID-19) pandemic has induced worldwide governments to adopt severe rules limiting individual freedom and imposing social distancing (eg, closing school, mandatory quarantine, restricting entertainments)1 in order to prevent the collapse of national health care systems. In addition to the goal of reducing the COVID-19 pandemic, this paradigm shift brings a different allocation of resources within diagnosis-related groups toward high-intensity levels of care (eg, intensive care units) needed for patients suffering of severe COVID-19. Although these measures are necessary in this pandemic, they constitute a barrier for health care professionals who are usually in close contact with patients needing low-intensity care, such as musculoskeletal (MSK) physical therapists
Carbon sequestration in a Mediterranean olive orchard managed sustainably over a 20-year period
Olive is a widespread crop within Mediterranean area and Italy is one of the biggest producer of olives and oil in the world. From an environmental point of view, centered on carbon (C) sequestration, managing olive orchards sustainably is an urgent and actual issue.
This trial was done in a 2-ha olive orchard (Olea europaea L., cv. ‘Maiatica’; 70-year-old plants, with a distance of 8 × 8 m and NE orientation) located in Ferrandina (Southern Italy, Basilicata region; N 40°29’; E 16°28’). The soil is a sandy loam (Haplic Calcisol - WRB), with a mean bulk density of 1.30 g cm–3 and sediment as parental material. The major landform is plain, the slope form is classified as convex-straight and the gradient class as gently sloping (2-5%). Half of the orchard has been managed using sustainable agricultural practices (sustainable management, Sung) for 20 years (2000-2020). Trees were drip-irrigated from March to October with urban wastewater. A light pruning was carried out every year during winter. The soil was permanently covered by spontaneous self-seeding weeds, mowed twice a year. Cover crop residues and prunings were shredded and left along the row as mulch.
The other half of the orchard was kept as ‘control’ plot. It was rainfed and conducted with a locally conventional management (Cmng), according to the practices usually adopted by farmers. The Cmng was managed by tillage performed 2-3 times per year to control weeds. Intensive pruning was carried out every two years, but pruned residues were removed from the orchard. A mineral fertilization was carried out once per year, during the fruit set and pit hardening phase (early spring).
The average value (n = 5; 0-100 cm soil depth) of baseline soil organic carbon (SOC) stock (related to the Cmng) in the 20-year period was 4.79 t SOC ha–1, with an average additional SOC storage potential because of the adoption of the Smng of 0.15 t SOC ha–1 yr–1, and a SOC stock after 20 years of Smng of 7.75 t SOC ha–1 yr–1.
In the Smng system, soil acted as a significant sink for C, especially due to the supplies of the organic resources internal to the system. The Smng system, made up of mature olive trees, was also able to fix in its aboveground and belowground components, a > 2-times higher total amount of C than the Cmng. Spontaneous vegetation was the most important pool, sequestering about 35% of the total fixed C. Also pruning material had a substantial importance in C fixation. Emissions of CO2 eq per kg of olives, calculated according to the Life Cycle Assessment (LCA), were 0.08 kg in the Smng system and 0.11 kg in the Cmng system. Besides C sequestration, the application of the Smng markedly improved physical, chemical, and biological soil fertility, with benefits on plants and production.
The application of a sustainable soil and plant management makes olive growing a multifunctional rural activity, not only aimed at production, but including many other objectives, such as environmental, landscaping cultural, social and recreational
Anticipated nursing care as perceived by nursing students: Findings from a qualitative study
Aim: To explore the perceptions of nursing students on the phenomenon of anticipated nursing care. Design: A descriptive-qualitative study was performed in 2019 according to the Consolidated Criteria for Reporting Qualitative Research principles. Methods: Data were collected using 16 face-to-face, audio-recorded interviews across four Italian Bachelor of Nursing degrees. Then, content analysis was performed, identifying, analysing and describing the anticipated nursing care phenomenon as perceived by nursing students. Results: Administering medications, providing fundamentals of care, managing some clinical procedures, freeing up the patient's bed and starting the shifts early emerged as the most anticipated nursing interventions. Stable, older patients who were more functionally dependent were reported to receive some fundamental nursing care before the expected time, while older, stable and more independent patients were used to receiving medications in advance. Anticipated nursing care is triggered by factors at the time management, resource, programming, professional and organizational levels
Agroecosystem diversification and sustainable management lead to increased biodiversity, crop production and socio-economic advantages: a case-study of an Italian olive orchard
- …