Search results for "Irrigation"

Editorial Comment on: In Vitro Investigations of Tissue-Engineered Multilayered Urothelium Established from Bladder Washings

2008

Horticultural management of Italian Pistachio orchard systems: current limitations and future prospective

2019

Pistachio production and consumption have strongly increased in the last years due to its capability to grow under limiting conditions, the profitability of this nut in the market and its well claimed healthy properties. The Sicilian pistachio industry is diminutive in comparison to big producing countries such as California and Iran. Its economical profitability is limited by a low productivity per surface area, strong alternate bearing, and long unproductive period, mainly associated with the lack of implementation of innovative management practices. This “traditional” agricultural system is surviving in a highly competitive international market thanks to the unique organoleptic profile o…

Verifica dell’applicabilità del metodo irriguo sub-superficiale su colture agrumicole e ottimizzazione dell’uso della risorsa idrica

2020

Gli impianti di subirrigazione (SDI), in relazione alla posizione interrata dei gocciolatori permettono la riduzione dei consumi irrigui, garantendo la possibilità di utilizzo di risorse altrimenti non utilizzabili. Tuttavia, i costi di investimento iniziali risultano maggiori di quelli relativi ai tradizionali impianti di microirrigazione e pertanto, diventano economicamente vantaggiosi, se l'efficienza del sistema viene garantita per periodi di almeno 15-20 anni. La SDI, inoltre, permette di ottenere valori elevati di efficienza d’uso dell’acqua, spesso superiori al 90%, se associata ad un monitoraggio continuo dello stato idrico del suolo e della pianta e ad una corretta stima delle esig…

Positive pressure irrigation (PPI) vs. passive ultrasonic irrigation (PUI), analysis to reduce vapour lock effect. Sistematic review and meta-analysis

2018

Irrigation and Political Power in the Medieval Kingdom of Valencia

2018

The medieval Kingdom of Valencia (Spain) was a European feudal society born in the thirteenth century out of the military conquest of the east of al-Andalus by the Crown of Aragon. This work focuses on the social organization of irrigation institutions in the thirteenth, fourteenth, and fifteenth centuries, which replaced the water management systems in use during the Andalusi period. The study analyzes the three types of water-governance systems in operation: irrigation systems managed by royal officials, irrigation systems managed by municipalities, and irrigation systems managed by corporations of autonomous farmers. The chapter also examines the different royal and municipal officials t…

Effects of precipitation seasonality, irrigation, vegetation cycle and soil type on enhanced weathering – modeling of cropland case studies across fo…

2022

Enhanced weathering (EW) is a promising strategy for carbon sequestration, but several open questions remain regarding the actual rates of dissolution in conditions of natural hydroclimatic variability in comparison to laboratory experiments. In this context, models play a pivotal role, as they allow exploring and predicting EW dynamics under different environmental conditions. Here a comprehensive hydro-biogeochemical model has been applied to four cropland case studies (i.e., Sicily and the Padan plain in Italy and California and Iowa in the USA) characterized by different rainfall seasonality, vegetation (i.e., wheat for Sicily and California and corn for the Padan plain and Iowa), and s…

Simplified Procedure to Evaluate Head Losses in Drip Irrigation Laterals

2005

The lateral lines of a drip irrigation system consist of pressurized pipelines with inline or online emitters. Proper hydraulic design of drip laterals usually requires the accurate evaluation of the total head losses, represented by friction losses along the pipe and the emitters, and local losses due to the emitter connections. This paper extends the local loss evaluation procedure, previously obtained for coextruded laterals, on the basis of new experiments. In addition, a simplified procedure was proposed based on the constant outlet discharge assumption for a quick evaluation of total head losses in drip irrigation lines, taking into account the total local loss due to the emitter conn…

Experimental Analysis of Local Pressure Losses for Microirrigation Laterals

2004

The accurate design of drip irrigation laterals needs to consider the variation of hydraulic head due to pipe elevation changes, head losses along the lines, and also, at a given operating pressure, emitter discharge variations related to manufacturing variability, clogging, and water temperature. Hydraulic head variations are consequent to both the friction losses and local losses due to the in-line or on-line emitters along the pipe, which determine the contraction and subsequent enlargement of the flow streamlines. Moreover, in-line emitters usually have a smaller diameter than the pipe, and therefore an additional friction loss must be considered. Evaluation of energy losses and consequ…

Influence of inspiration to expiration ratio on cyclic recruitment and derecruitment of atelectasis in a saline lavage model of acute respiratory dis…

2015

OBJECTIVE Cyclic recruitment and derecruitment of atelectasis can occur during mechanical ventilation, especially in injured lungs. Experimentally, cyclic recruitment and derecruitment can be quantified by respiration-dependent changes in PaO2 (ΔPaO2), reflecting the varying intrapulmonary shunt fraction within the respiratory cycle. This study investigated the effect of inspiration to expiration ratio upon ΔPaO2 and Horowitz index. DESIGN Prospective randomized study. SETTING Laboratory investigation. SUBJECTS Piglets, average weight 30 ± 2 kg. INTERVENTIONS At respiratory rate 6 breaths/min, end-inspiratory pressure (Pendinsp) 40 cm H2O, positive end-expiratory pressure 5 cm H2O, and FIO2…

Analysis of atelectasis, ventilated, and hyperinflated lung during mechanical ventilation by dynamic CT.

2005

Study objective: To study the dynamics of lung compartments by dynamic CT (dCT) imaging during uninterrupted pressure-controlled ventilation (PCV) and different positive end-expiratory pressure (PEEP) settings in healthy and damaged lungs. Design: Experimental animal investigation. Setting: Experimental animal facility of a university department. Interventions: In seven anesthetized pigs, static inspiratory pressure volume curves were obtained to identify the individual lower inflection point (LIP) before and after saline solution lung lavage. During PCV, PEEP was adjusted 5 millibars (mbar) below the individually determined LIP (LIP - 5), at the LIP, and 5 mbar above the LIP (LIP + 5). Mea…