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Irrigation districts play a decisive role in Portuguese agriculture and require the adaptation to the new water management paradigm through a change in technology and practices compatible with farmers&rsquo, technical know-how and economic sustainability. Therefore, improvement of water management, focusing on water savings and increasing farmers&rsquo, income, is a priority. In this perspective, an applied research study is being carried out on the gravity-fed Lis Valley Irrigation District to assess the performance of collective water supply, effectiveness of water pumping, and safety of crop production due to the practice of reuse of drainage water. The water balance method was applied at irrigation supply sectors, including gravity and Pumping Irrigation Allocation. The average 2018 irrigation water allocated was 7400 m3/ha, being 9.3% by pumping recharge, with a global efficiency of about 67%. The water quality analysis allowed identifying some risk situations regarding salinization and microbiological issues, justifying action to solve or mitigate the problems, especially at the level of the farmers&rsquo, fields, according to the crops and the irrigation systems. Results point to priority actions to consolidate improved water management: better maintenance and conservation of infrastructure of hydraulic infrastructures to reduce water losses and better flow control, implementation of optimal operational plans, to adjust the water demand with distribution, improvement of the on-farm systems with better water application control and maintenance procedures, and improvement of the control of water quality on the water reuse from drainage ditches. The technological innovation is an element of the modernization of irrigation districts that justifies the development of multiple efforts and synergies among stakeholders, namely farmers, water users association, and researchers.

This paper aims to analyse the rice production system in the lower Mondego Valley, in Portugal, in order to understand the main concerns of farmers and risk perception. A field survey was conducted and rice production systems as well as marketing systems were analysed. A study on the worries was also made and a correlational attempt was done, considering different types of risk. The results show a production system strongly oriented by agricultural policies and agri-environmental measures. The perceived risks mainly arise from rice production costs, prices and their relative instability which results from the uncertainty about the evolution of worldwide demand and production, and from the effects of global changes. However, the choices made by farmers, who possess sound knowledge of agricultural policies and marketing systems, are not completely correlated with their risk perceptions.

This paper presents a study of the monitorization of the conveyance system of the collective water network in the framework of the Lis Valley Water Management Operational Group, aiming the improvement of water management by the Water Users’ Association. The methodology considered the measurement of water allocation to main canals, its distribution throughout the conveyance system, and the on-farm irrigation demand. This paper presents the results of Canal 2, for 2019 and 2020 irrigation seasons. This canal supplies an area of 410 ha, is gravity-fed from Lis river, on the Arrabalde weir, in Leiria, and has a pumping recharge during the irrigation peak period. A water balance of supply and irrigation demand was carried out at 10-day period, to evaluate the performance of the distribution water management. The analyzed system reveals the specificity of the drainage water reuse, which leads to a more flexible management of water allocated by gravity-fed, and rational of pumping supply, in order to adjust it to irrigation demand, through energy consumption. Results point to actions that prioritize consolidating the improvement management of water resources, like the implementation of optimal operational plans to adjust the water demand with distribution, accompanied with the improvement of the on-farm irrigation systems.

Irrigation plays an important role in agriculture, with impact on land productivity and economic prosperity of farmers. Water management is complex but can benefit from remote sensing satellite images, which provide a monitoring of soil, crops and water, in harmony with the requirements of precision agriculture. The surface data from the combined constellation Sentinel-2A, 2B and Landsat 8 offer unique opportunities with this aim. The SpiderwebGIS tool, developed by the Instituto de Desarrollo Regional, from the University of Castilla La-Mancha (UCLM), allows a friendly management of satellite images, providing information to the community in a simple and accessible way. This communication explores the potential applications of remote sensing in irrigation management at district scale, aiming to improve water management in the plots, under the responsibility of farmers, and in collective distribution, by water users’ associations. This study focuses on the Lis Valley Irrigation District. The methodology considers ground observations at a local scale of climate, soil and plant parameters, for the development and calibration of models based on satellite images. The ultimate objective is the operational use of temporal series of spatially distributed information to support agricultural management and optimize the use of water, energy and economic resources. This study is supported by Instituto Politecnico de Coimbra and UCLM and is integrated into the activities of the Lis Valley Water Management Operational Group.

The innovation of agricultural systems management is a determinant factor that guarantees adaptation to a new paradigm of global economy, environmental protection, and social requirements. The conventional concepts of innovation, applicable to new products and processes, do not consider many characteristics of the agricultural sector, such as social innovation and innovation resulting from new or renewed processes. Nevertheless, the overall impact of innovation on yields, competitiveness, and value can be hampered by the limited understanding or misinterpretation of Agriculture Innovation paradigms. For instance, the Rural Development Program (RDP) applies a restrict concept of innovation, being unable to embrace the full range of activities intended to implement new practices within the framework of the Agricultural Knowledge and Innovation System (AKIS). Stimulating innovation in agriculture demands a change in policy innovation of RDP in order to preserve natural resources and combine agricultural priorities and the rural environment with the concepts of innovation. This paper focuses on the different views of the concept of innovation within the Program of Operational Groups (OGs) of the European Innovation Partnership for Agricultural Productivity and Sustainability (EIP-AGRI), analyzing the Portuguese case study of the Lis Valley Irrigation District whose main innovation objective was to achieve and implement new processes of water management aiming at the conservation of natural resources as well as sustainable social and economic agricultural development. The Portuguese experience highlights why the application of innovation in agriculture may not reach the desirable outcomes info:eu-repo/semantics/publishedVersion

The new technologies of surface irrigation require the adoption of effective Laser-controlled precision land levelling (PLL) to reach the high irrigation performance standards, with significant benefits on water saving, salinity control, crop productivity, and farmer’s income. This study aimed to assess the performance and the impacts of PLL on surface irrigation systems, focusing the maize crop on the irrigation districts Hetao (China) and Lower-Mondego (Portugal). The experimental study at field scale assessed the PLL and evaluated the on-farm irrigation under precise levelled fields and well management practices. PLL operators have been inquired to improve the knowledge about hiring services. The design of surface irrigation scenarios allowed to explain the effects of field size and slope on irrigation and land levelling performance. The best practice to manage the PLL maintenance is an important issue to guarantee a high effectiveness of irrigation performance. The optimization of PLL appeals the application of best soil tillage practices and the monitoring of soil surface elevations with newest information technologies. Efficient operational guidelines to support the PLL planning, schedule, and operation, well trained operators and carefully adjusted equipment, are key factors to the improvement.

Intercropping is commonly used in the Hetao irrigation district, upper Yellow River basin, where the main crops are wheat, maize and sunflower. For a better use of land, water, radiation energy, and nutrients, spring wheat is traditionally intercropped with maize (W–M) and, more recently, with sunflower (W–S). Considering the need to reduce diversions of water for irrigation in Hetao, this study aims to assess crop water use of W–M and W–S intercropping systems in comparison to the same crops in monocropping. The dual crop coefficient approach was adopted with the SIMDualKc model, which allows partitioning crop evapotranspiration into crop transpiration and soil evaporation. A new model approach was tested to compute a combined basal crop coefficient for the intercropping, K cb inter , which uses the daily values of the K cb of the component crops together with the respective heights and fractions of ground covered by the crops. SIMDualKc was first calibrated and validated for wheat, maize and sunflower as single crops using field data of 2010–2012 and was later used with the new developed approach, which was validated with W–M and W–S field data of 2010–2011. The K cb values calibrated for wheat, maize and sunflower compared well with literature and goodness of fit indicators have shown high accuracy of simulations used for calibration and validation. Results evidenced the importance of groundwater contribution in Hetao, and that soil evaporation is there low under surface irrigation. Moreover, it was found that actual evapotranspiration, crop transpiration, irrigation water use and groundwater contribution of intercropping systems were larger than those of the component sole crops, which led to significantly higher yields of intercropping relative to those of single crops.

Plastic-film mulching has played an important role to promote agricultural production in arid areas; however, due to its inefficient recycling capacity, large amounts of residues have been accumulated in soils, causing negative impacts on crop growth and on the environment. To investigate these effects on water use efficiency, a two-years field experiment was carried out, applying different levels of plastic-film residues, from 0 to 600 kg ha−1. Results show that these residues have a negative impact on root and shoot growth at several growth stages of corn crop, particularly if above 300 kg ha−1. Root length and weight density decrease with the amount of residues throughout the majority of crop season. Plastic-film residues of about 600 kg ha−1 are responsible for the decrease of the biomass root to shoot ratio during the tasseling stage. Moreover, during physiological maturity, root and shoot revealed the highest sensitivity, and the least negative effects on the root system. Results also show that crop water consumption has a slight decrease with the plastic-film residues, though there was also a significant decrease of the yield and the water use efficiency reduction. This information allows to state that it is determinant to learn how to deal with the problem, adjusting the irrigation and crop management to avoid yield impacts. It would also be important to find an efficient procedure to mechanically collect the residues in the soil, and to apply new biodegradable film mulching.

Surface irrigation is the oldest and most widely used irrigation method, more than 83% of the world’s irrigated area. It comprises traditional systems, developed over millennia, and modern systems with mechanized and often automated water application and adopting precise land-leveling. It adapts well to non-sloping conditions, low to medium soil infiltration characteristics, most crops, and crop mechanization as well as environmental conditions. Modern methods provide for water and energy saving, control of environmental impacts, labor saving, and cropping economic success, thus for competing with pressurized irrigation methods. Surface irrigation refers to a variety of gravity application of the irrigation water, which infiltrates into the soil while flowing over the field surface. The ways and timings of how water flows over the field and infiltrates the soil determine the irrigation phases—advance, maintenance or ponding, depletion, and recession—which vary with the irrigation method, namely paddy basin, leveled basin, border and furrow irrigation, generally used for field crops, and wild flooding and water spreading from contour ditches, used for pasture lands. System performance is commonly assessed using the distribution uniformity indicator, while management performance is assessed with the application efficiency or the beneficial water use fraction. The factors influencing system performance are multiple and interacting—inflow rate, field length and shape, soil hydraulics roughness, field slope, soil infiltration rate, and cutoff time—while management performance, in addition to these factors, depends upon the soil water deficit at time of irrigation, thus on the way farmers are able to manage irrigation. The process of surface irrigation is complex to describe because it combines surface flow with infiltration into the soil profile. Numerous mathematical computer models have therefore been developed for its simulation, aimed at both design adopting a target performance and field evaluation of actual performance. The use of models in design allows taking into consideration the factors referred to before and, when adopting any type of decision support system or multicriteria analysis, also taking into consideration economic and environmental constraints and issues. There are various aspects favoring and limiting the adoption of surface irrigation. Favorable aspects include the simplicity of its adoption at farm in flat lands with low infiltration rates, namely when water conveyance and distribution are performed with canal and/or low-pressure pipe systems, low capital investment, and low energy consumption. Most significant limitations include high soil infiltration and high variability of infiltration throughout the field, land leveling requirements, need for control of a constant inflow rate, difficulties in matching irrigation time duration with soil water deficit at time of irrigation, and difficult access to equipment for mechanized and automated water application and distribution. The modernization of surface irrigation systems and design models, as well as models and tools usable to support surface irrigation management, have significantly impacted water use and productivity, and thus competitiveness of surface irrigation.

Water resources management in the Yellow River basin, China, is facing a paradigmatic change in consequence of an unbalanced supply and demand due to an increased demand for water from non-agricultural sectors and a reduced supply due to climate change that reduced precipitation and increased climatic demand. The problem is aggravated by low equity of spatial water allocation in the basin. A supply reduction in the upstream basin area aims to control the water scarcity conditions occurring in the middle and lower reaches of the basin. Forecasted scenarios on water resources allocation and use for agriculture in the upper reaches of the Yellow River basin point out for the need to reduce irrigation water withdrawal and increasing land and water productivity. This paper focus on the Hetao Irrigation District, Inner Mongolia, in upper reaches of Yellow River, where sustainable water saving irrigation is being implemented in response to global changes occurring in the Yellow River basin. That implementation requires technological adaption referring to modernization of canal water conveyance and delivery, which refers to upgrading the hydraulic regulation and control structures, reducing operational runoff wastages, and improving system management. At field level, modern irrigation technologies adapted to local conditions are under implementation. The paper focus on an application to Dengkou area.

The increasing pressure on water resources is due to continuously growing consumption, which itself results from demographic and economic developments and the effect of expected climate change. Therefore, action to encourage the more efficient and productive use of water is urgent. Water management needs to focus on regulating the use of this limited resource by multiple users; the allocation of water to non-agricultural users, in particular, is increasing steadily. Moreover, increased variability in climate regimes is expected to modify the volume, temporal and spatial distribution of water storage and fluxes, and therefore to affect the distribution, availability and sustainability of regional water resources. Irrigated agriculture is one of the sectors also facing new challenges. Given that water scarcity is expected to worsen in large agricultural production areas, one such challenge is how to maintain or increase sustainable agricultural production under growing water use restrictions. Improvements in agricultural water management should seek to conserve not only water but energy and soil, too, while still satisfying society’s relentless demand for high quality food and fiber crops, and livestock, aquatic and forest products. This work addresses the main problems related to this topic, illustrated with case studies from Europe and Asia.

Research Paper Water-saving irrigation needs to be implemented in Hetao irrigation district to help satisfying the demand by other users in the Yellow River basin. Aiming at assessing the potential irrigation performance and water saving at farm level, a set of traditional basins and another of precision-levelled basins cropped with maize, wheat and sunflower and managed by farmers were evaluated. Data were collected to characterise the basin sizes, microtopography, inflow rates, advance and recession times, cut-off time and soil water content. In addition, families of infiltration curves were derived from field observations and subsequent use of model SIRMOD. Infiltration was higher for the precision-levelled basins and decreased from the first to the next irrigation events. Infiltration data were used to support the computation of distribution uniformity (DU), beneficial water use fraction (BWUF) and deep percolation (DP). For traditional basins, DU and BWUF were low and DP was high. When precise land levelling was practised, DU increased greatly to near 94% but BWUF improved little, because irrigation scheduling was inadequate leading to excessive water application; however, non-negligible water saving was achieved for maize and wheat since they have higher irrigation demand. In contrast, simulating the application of an appropriate irrigation scheduling through adjusting the cut-off time led to an approximately unchanged DU but BWUF greatly increased and DP reduced to 10% on average. This condition represents a potential water saving of 34e39%; however its achievement requires improved design of farm systems, appropriate irrigation water deliveries and scheduling, and the support and training of farmers info:eu-repo/semantics/publishedVersion

O Tribunal Constitucional tem sido chamado, repetidamente, a apreciar a constitucionalidade da norma do artigo 52.º da Lei n.º 107/2009, de 14 de setembro, que estabelece um prazo único de cinco anos para a prescrição do procedimento por contraordenação laboral (ou de segurança social), independentemente da gravidade da infração, do grau de culpa do infrator, da sua capacidade económica ou da moldura aplicável. Numa jurisprudência uniforme e constante, sufragada pelo Ministério Público nos vários recursos por este apresentados sobre a temática, o Tribunal Constitucional tem considerado que o prazo único de cinco previsto naquela norma está em conformidade com a ampla liberdade atribuída ao legislador ordinário no que respeita, designadamente, à extinção da responsabilidade contraordenacional por prescrição. Tal entendimento não está, no entanto, isento de dúvidas. O presente trabalho não pretende esgotar o tema, amplamente debatido entre a jurisprudência e a doutrina. Os nossos propósitos são modestos. Queremos fomentar o debate e, quem sabe, contribuir, ainda que indiretamente, para um revisão do regime geral e dos regimes especiais do direito contraordenacional, e particular do regime das contraordenações laborais., Revista de Ciências Empresariais e Jurídicas / Review of Business and Legal Sciences, n. 28 (2017): Revista de Ciências Empresariais e Jurídicas / Review of Business and Legal Sciences

This study explores the use of drip and surface irrigation decision support systems to select among furrow, border and drip irrigation systems for cotton, considering water saving and economic priorities. Data refers to farm field observations in Northeast of Syria. Simulation of drip irrigation was performed with MIRRIG model for various alternatives: double and single row per lateral, emitter spacing of 0.5 and 0.7 m, six alternative pipe layouts and five self-compensating and non-compensating emitters. Furrow and border irrigation alternatives were designed and ranked with the SADREG model, considering lasered and non-lasered land levelling, field lengths of 50–200 m and various inflow discharges. A multicriteria analysis approach was used to analyse and compare the alternatives based upon economic and water saving criteria. Results for surface irrigation indicate a slight advantage for long non-lasered graded furrows; non-lasered alternatives were selected due to economic considerations. For drip irrigation, the best ranking is for systems having lower costs, mainly with double rows per lateral and larger emitter spacing. Comparing surface and drip irrigation systems, despite low cost, drip alternatives may lead to 28–35% water saving relative to improved graded furrows, and increase water productivity from 0.43 kg m −3 to 0.61 kg m −3 , surface irrigation provides higher farm returns. Drip irrigation is selected only when high priority is assigned to water saving. Deficit irrigation does not change this pattern of results. Apparently, adopting drip irrigation requires appropriate economic incentives to farmers, changes in the structure of production costs and increased value of production.

Improving surface irrigation systems for cotton in Ras-El-Ain district, Northeast Syria, needs finding alternative solutions that provide for both water saving and farm economic benefits in a context of small and family farms. Multicriteria analysis was used to evaluate and rank a set of furrow and border irrigation alternatives, with and without precise land leveling, that were created with the decision support system SADREG. This approach allowed to consider various criteria, mainly water saving and farm economics. Results show that both graded furrow and border alternatives are acceptable, with a slight advantage for graded furrows. Alternatives without land leveling have shown to be more appropriate when focusing farm economic results, while alternatives including land leveling were selected when priorities were assigned to water saving. These results relate with higher costs of alternatives that consider land leveling. Equipment for appropriate control of inflow rates was considered for all cases. The improved alternatives may lead to savings of 20–28% of irrigation water and increasing the irrigation water productivity from present 0.31 to 0.44 kg m−3. When the same alternatives were ranked for a 20% deficit irrigation their rankings changed, with reduced ranks of alternatives requiring land leveling. This is due to the fact that yields and yield values are reduced with deficit irrigation, thus making it less favorable to select alternatives that imply higher costs. The study shows that adopting more advanced but more costly irrigation technologies aimed at water saving requires appropriate economic incentives, training of farmers and an institutional framework able to support the sustainable use of water in irrigation.

This study describes an application of the SADREG decision support system to cotton furrow irrigation in Central Fergana Valley, Uzbekistan. This application aims at modernizing furrow irrigation and is based upon field trials on crop water requirements and surge irrigation. A large number of design alternatives were generated for a typical field, which were compared in terms of water use, irrigation water productivity, irrigation costs and yield value. This comparison has shown that alternatives that favour water use performance are different from those leading to higher farm incomes. For multicriteria analysis, three different prioritization schemes were analysed, one relative to economic results, another referring to water saving, and the third representing a balanced situation between the two. Very different rankings resulted, with alternatives ranked high for economic results being ranked low for water saving, and vice-versa. The high ranked alternatives for the balanced prioritization scheme are common to the other two, but the decision demands further consideration of risk factors and users’ preferences. This application shows that adopting water saving technologies and deficit irrigation is generally difficult in economic terms, thus requiring support to farmers if their income is to be maintained.

The SADREG decision support system was developed to help decision makers in the process of design and selection of farm surface irrigation systems to respond to requirements of modernization of sur...

Water saving in irrigation is a main issue in the Yellow River basin. This paper refers to a field and modelling study performed in the Huinong Irrigation District, a very large surface irrigation system in Ningxia, upper Yellow River basin, intended to assess water saving and improved water use issues. The decision support system SEDAM was purposefully developed to evaluate alternative scenarios of improvements of farm and off-farm irrigation canal systems. It includes a demand and delivery simulation tool and adopts multicriteria analysis. Simulation is performed at various scales, starting at the distributor and then successively at the sub-branch, branch and sector scales. It uses a database built from random generation of system characteristics at these scales, and based on field surveys. Demand is built from exploring interactively the irrigation scheduling simulation model ISAREG and the surface irrigation models SRFR and SIRMOD, which were previously parameterized. The first is used to generate improved irrigation schedules and the second to define improved basin irrigation scenarios. In addition, a simple paddy irrigation tool is used to simulate replacing the current deep flooding method by shallow water irrigation. Water delivery scenarios are built to match those of demand including several improved procedures that aim at controlling runoff and seepage. Results indicate that progressively adopting farm and delivery system improvements leads to reduced canal seepage and runoff, which is essential to an effective functioning of the drainage system, in addition to control diversions into the Huinong canal. Water savings amount to more than 50% of actual water use. However, results referring to the economic criteria, particularly to the farm gross margin, reveal that more stringent improvements have low impacts, i.e. the respective utilities increase little when scenarios require higher investments. The described application shows that adopting a DSS simulation model and multicriteria analysis is appropriate to assess water use improvements in large irrigation systems and that it is advantageous to perform the analysis of related impacts by combining economic and environmental criteria. The importance of adopting improved delivery systems is also evidenced.

Water saving in irrigation is a key concern in the Yellow River basin. Excessive water diversions for irrigation waste water and produce waterlogging problems during the crop season and soil salinization in low lands. Supply control and inadequate functionality of the drainage system were identified as main factors for poor water management at farm level. Their improvement condition the adoption of water saving and salinity control practices. Focusing on the farm scale, studies to assess the potential for water savings included: (a) field evaluation of current basin irrigation practices and further use of the simulation models SRFR and SIRMOD to generate alternative improvements for the surface irrigation systems and (b) the use of the ISAREG model to simulate the present and improved irrigation scheduling alternatives taking into consideration salinity control. Models were used interactively to define alternatives for the irrigation systems and scheduling that would minimize percolation and produce water savings. Foreseen improvements refer to basin inflow discharges, land leveling and irrigation scheduling that could result in water savings of 33% relative to actual demand. These improvements would also reduce percolation and maintain water table depths below 1 m thereby reducing soil salinization.

To improve water saving and conservation in irrigated agriculture, a range of field evaluation experiments was carried out with various furrow irrigation treatments in cotton fields to estimate the possibilities of improving furrow irrigation performances under conditions of Central Fergana Valley, Uzbekistan. The research consisted in comparing surge and continuous-flow in long furrows and adopting alternate-furrow irrigation. The best results were achieved with surge-flow irrigation applied to alternate furrows. Field data allowed the calibration of a surface irrigation model that was used to identify alternative management issues. Results identified the need to better adjust inflow rates to soil infiltration conditions, cut-off times to the soil water deficits and improving irrigation scheduling. The best irrigation water productivity (0.61 kg m −3 ) was achieved with surge-flow on alternate furrows, which reduced irrigation water use by 44% (390 mm) and led to high application efficiency, near 85%. Results demonstrated the possibility for applying deficit irrigation in this region.

The Aral Sea basin is a region that faces water scarcity due to aridity and man-made desertification. To reduce the disproportion between water demand and supply improved water management is required, particularly aimed at water saving and conservation in irrigated agriculture. One main issue is demand management by reducing the farm irrigation water demand by improved crop irrigation management since the modernization and rehabilitation of the conveyance and distribution systems are presently out of the scope in Uzbekistan. Under this perspective, the improvement of furrow irrigation systems, which are used on 98% of the irrigated lands, is a main issue. To assess the potential for improving the performance of furrow irrigation in the central part of the Fergana Valley, Uzbekistan, a set of evaluation experiments was carried out. Irrigation management alternatives included several furrow inflow rates (1.2–2.4 l/(s furrow)) and furrow lengths (130 and 400 m); comparing every-furrow irrigation with alternate-furrow irrigation. Results were evaluated through the application efficiency (Ea), the distribution uniformity (DU) and total applied irrigation depths. The best performances were obtained for alternate long furrows adopting the inflow rate of 1.8 l/(s furrow), which produced high Ea and DU, superior to 80 and 83%, respectively, and led to seasonal water savings from 200 to 300 mm when compared with actual water use in every-furrow

We present the results of a three-dimensional Monte Carlo radiative transfer code for starless molecular cloud cores heated by an external isotropic or non-isotropic interstellar radiation field. The code computes the dust temperature distribution inside model clouds with specified but arbitrary density profiles. In particular we examine in detail spherical (Bonnor-Ebert) clouds, axisymmetric and non-axisymmetric toroids, and clouds heated by an external stellar source in addition to the general interstellar field. For these configurations, the code also computes maps of the emergent intensity at different wavelengths and arbitrary viewing angle, that can be compared directly with continuum maps of prestellar cores. In the approximation where the dust temperature is independent of interactions with the gas and where the gas is heated both by collisions with dust grains and ionization by cosmic rays, the temperature distribution of the gas is also calculated. For cloud models with parameters typical of dense cores, the results show that the dust temperature decreases monotonically from a maximum value near the cloud's edge (14-15 K) to a minimum value at the cloud's center (6-7 K). Conversely, the gas temperature varies in a similar range, but, due to efficient dust-gas coupling in the inner regions and inefficient cosmic-ray heating in the outer regions, the gradient is non-monotonic and the gas temperature reaches a maximum value at intermediate radii. The emission computed for these models (at 350 micron and 1.3 mm) shows that deviations from spherical symmetry in the density and/or temperature distributions are generally reduced in the simulated intensity maps (even without beam convolution), especially at the longer wavelengths., 12 pages, 6 figures. Astronomy and Astrophysics, in press

We have observed the dark cloud Barnard 68 with SCUBA at 850 um and with SIMBA at 1.2 mm. The submillimetre and millimetre dust emission correlate well with the extinction map of Alves, Lada and Lada (2001).The A_V/850um correlation is clearly not linear and suggests lower temperatures for the dust in the inner core of the cloud. Assuming a model for the temperature gradient, we derive the cloud-averaged dust emissivities (normalised to the V-Band extinction efficiency) at 850 um and 1.2 mm. We find k_850um/k_V = 4.0 +/- 1.0 x 10^-5 and k_1.2mm/k_V = 9.0 +/- 3.0 x 10^-6. These values are compared with other determinations in this wavelength regime and with expectations for models of diffuse dust and grain growth in dense clouds., 8 pages, 4 figures, A&A accepted (Letter), referee format

Little is known about beta-lactam and beta-lactamase inhibitor susceptibilities of uropathogenic Escherichia coli isolates from animals. Seventy-two isolates collected from canine urinary tract infections were studied by disc diffusion and microdilution methods. The mechanisms responsible for amoxicillin resistance were associated with the production of beta-lactamases in 26 (36%) isolates. These beta-lactamases were further characterized by isoelectric focusing (IEF) and PCR, and bla(TEM), bla(OXA-1), bla(SHV) and ampC genes were detected. The isolates were highly resistant to amoxicillin and ticarcillin, with MIC(90)s of 2048 mg/L. The MIC(90) of cefalothin was 128 mg/L, but the MIC(90)s of ceftazidime, ceftriaxone, cefotaxime and aztreonam were lower (0.5, 0.06, 0.25 and 0.5 mg/L, respectively). Fourteen isolates were not inhibited by clavulanate. The mechanisms of resistance to beta-lactams and beta-lactamase inhibitors involved the presence of TEM-1 beta-lactamase in 20 isolates, which had an isoelectric point (pI) of 5.4 and were positive for the presence of the bla(TEM) gene. Fourteen of these isolates produced TEM-1 beta-lactamase alone, and the other six showed an additional band at pI 9.0-9.2 on IEF and the ampC gene by PCR, indicating the simultaneous production of AmpC enzyme. IEF showed that one isolate produced AmpC alone and PCR detected the presence of the ampC gene. Three of the 26 beta-lactamases with a pI of 7.6 belonged to the SHV family, which was confirmed by the presence of the bla(SHV) gene. The remaining two beta-lactamases were OXA-1 focusing at 7.4, and were encoded by the bla(OXA-1) gene. Resistance to beta-lactamase inhibitors was mediated mainly by TEM-1 alone (six of 26) or together with AmpC (four of 26), AmpC alone (one of 26), SHV (one of 26) and OXA-1 (two of 26) enzymes. Clear resistance to extended-spectrum cephalosporins, ceftazidime and ceftriaxone (64 mg/L), was found in one isolate. Isolates producing either AmpC or OXA-1 enzymes or producing high levels of TEM-1 beta-lactamases had susceptibility patterns that were difficult to distinguish without IEF and/or amplification of the corresponding specific genes. This work supports the need for antimicrobial resistance surveillance in veterinary medicine.

Neste trabalho, investigamos o processo de implantação de um sistema/software de apoio à estratégia da saúde da família em um bairro do município do Rio de Janeiro. Nesse sentido, procuramos compreender como se estruturam as redes de colaboração entre os atores que vêm negociando as decisões sobre a customização deste software. Utilizando a metodologia da Teoria Ator-Rede (TAR), mapeamos os registros desta colaboração durante a estabilização do ecossistema pesquisado. Além disso, buscamos conciliar e confrontar, simultaneamente, as hipóteses dos estudos em Colaboração em Engenharia de Software com os Estudos Ciência-Tecnologia-Sociedade (CTS), concluindo que existem oportunidades de diálogo entre ambos.

The distribution of alleles I, II and III of the P adhesin gene papG among Escherichia coli isolated from urinary tract infections in humans, dogs and cats was studied by PCR. Allele I was present in 6% and 5% of the human and cat isolates. Allele II as such was present in 30% and 22%, or in association with allele III in 12% and 2% of the human and canine isolates, respectively. Allele III was present in 33% of the human strains and predominated largely over allele II in E. coli isolates from cystitis of animal origin (72% in dog and 95% in cat strains). The three different classes of the PapG adhesin have been suggested to play a role in host specificity, for example human versus canine specificity. Recent studies, however, showed papG III positive human and dog cystitis isolates to be largely indistinguishable. We found the Class II allele in animal isolates and detected for the first time in Europe the Class I allele in a different genetic background than the J96-like clonal group. Our findings show that uropathogenic E. coli isolates from different species can have the same papG alleles and thus may have zoonotic potential.

This study aims to assess the economic feasibility of full and deficit irrigated maize using center pivot, set sprinkler systems and drip tape systems through multicriteria analysis. Different irrigation treatments were evaluated and compared in terms of beneficial water use and physical and economical water productivity for two commodity prices and three irrigation systems scenarios applied to a medium and a large field of 5 and 32 ha respectively. Results show that deficit treatments may lead to better water productivity indicators but deficit irrigation (DI) feasibility is highly dependent on the commodity prices. Various well-designed and managed pressurized irrigation systems’ scenarios – center-pivot, set sprinkler systems and drip tape systems – were compared and ranked using multicriteria analysis. For this, three different prioritization schemes were considered, one referring to water savings, another relative to economic results, and a third one representing a balanced situation between the first two. The rankings of alternative solutions were very sensitive to the decision-maker priorities, mainly when comparing water saving and economic results because the selected alternatives were generally not common to both priority schemes. However, some of the best alternatives for the balanced priorities scheme are common to the other two, thus suggesting a possible trade-off when selecting the best alternatives. Deficit irrigation strategies also rank differently for the various scenarios considered. The study shows that deficit irrigation with exception of mild DI is generally not economically feasible. The adoption of well designed and managed irrigation systems requires consideration of priorities of farm management in terms of water saving and economic results since that some water saving solutions do not allow appropriate recover of the investment costs, particularly with DI. Basing decisions upon multicriteria analysis allows farmers and decision-makers to better select irrigation systems and related management decisions. Results also indicate that appropriate support must be given to farmers when adopting high performance but expensive irrigation systems aimed at sustainable crop profitability.

This paper presents an overview of a Wireless Sensor and Actuator Network (WSAN) used to monitor an electrical power grid distribution infrastructure. The WSAN employs appropriate sensors to monitor key grid components, integrating both safety and security services, which improve the grid distribution dependability. The supported applications include, among others, video surveillance of remote secondary substations, which imposes special requirements from the point of view of quality of service and reliability. The paper presents the hardware and software architecture of the system together with performance results.

This paper presents the Web-based decision support system SADREG for design and selection of farm surface irrigation systems: furrows, basin and border irrigation. The design component applies database information and produces a set of design alternatives in agreement with the user options through several simulation and computational tools. The selection component applies multicriteria analysis to rank those alternatives. Comparing with the conventional stand-alone PC-program, an Internet application has a larger flexibility enabling the access by users worldwide, particularly in areas where expert technical support for surface irrigation improvement is more incipient. Moreover, it allows an easier transfer and share of knowledge and tools to improve the procedures of irrigation design. The Web SADREG application includes the Web module that creates the user interface, data fluxes, showing numerical and graphical data, and the simulation engine, which runs the simulation models on the server. The development applies the PHP and C++ languages to achieve a better flexibility and to minimize client system requirements and SQLServer for data storing, thus allowing a simultaneous connection of several users. During the simulation process the users are informed about the input parameters, the design process and the output. An online help and information about irrigation equipments and guidelines for a good irrigation practices is available. This approach results on a better service quality, avoiding package installation and is more versatile to upgrade and to integrate other data and models. This software, available on http://sadreg.safe-net.eu Web site, is currently being tested.

Magnetic fields are believed to play a crucial role in the process of star formation. We compare high-angular resolution observations of the submillimeter polarized emission of NGC 1333 IRAS 4A, tracing the magnetic field around a low-mass protostar, with models of the collapse of magnetized molecular cloud cores. Assuming a uniform dust alignment efficiency, we computed the Stokes parameters and synthetic polarization maps from the model density and magnetic field distribution by integrations along the line-of-sight and convolution with the interferometric response. The synthetic maps are in good agreement with the data. The best-fitting models were obtained for a protostellar mass of 0.8 solar masses, of age 9e4 yr, formed in a cloud with an initial mass-to-flux ratio ~2 times the critical value. The magnetic field morphology in NGC 1333 IRAS 4A is consistent with the standard theoretical scenario for the formation of solar-type stars, where well-ordered, large-scale, rather than turbulent, magnetic fields control the evolution and collapse of the molecular cloud cores from which stars form., Comment: 4 pages, 5 figures. Accepted by Astronomy and Astrophysics

Genotypic differences regarding virulence factors between human and animal E. coli strains were observed in this work. They consisted mainly on the frequencies and type of adhesin encoded operons detected, which may reveal uropathogenic E. coli adaptation to different host cell receptors. Low detection of the cnf1 gene in human hemolytic E. coli strains suggests the possibility that, in these strains, other cytotoxins may be involved in the pathogenesis of urinary tract infection.

In our study, negative cultures were 60,6%, perhaps because of concurrent antimicrobial therapy or poor clinical evaluation. In this work, Proteus mirabilis is the major pathogen, followed by E. coli, probably because Proteus mirabilis is commonly associated with recurrent urinary tract infections in dogs thus providing easily detectable clinical signs (haematuria).

We compute polarization maps for molecular cloud cores modeled as magnetized singular isothermal toroids, under the assumption that the emitting dust grains are aspherical and aligned with the large-scale magnetic field. We show that, depending on the inclination of the toroid with the line-of-sight, the bending of the magnetic field lines resulting from the need to counteract the inward pull of gravity naturally produces a depolarization effect toward the centre of the map. We compute the decrease of polarization degree with increasing intensity for different viewing angles and frequencies, and we show that an outward increasing temperature gradient, as expected in starless cores heated by the external radiation field, enhances the decrease of polarization. We compare our results with recent observations, and we conclude that this geometrical effect, together with other mechanisms of depolarization, may significantly contribute to the decrease of polarization degrees with intensity observed in the majority of molecular cloud cores. Finally, we consider the dependence of the polarization degree on the dust temperature gradient predicted for externally heated clouds, and we briefly comment on the limits of the Chandrasekhar-Fermi formula to estimate the magnetic field strength in molecular cloud cores., Comment: 15 pages, 9 figures. Astronomy and Astrophysics, in press

Demand simulation is relevant to identify main problems of current excess water use, and to evaluate alternative improvements both at the farm and the distribution scales. Demand simulation is performed first at the unit/distributor level, and is then aggregated to the branch and the sector. At the unit level, the demand is estimated from the irrigation schedules at farm and the performance of the water application at field. Aggregation to the branch canal system and to the Sector is performed using simplified management delivery rules and following the process of water allocation currently applied. These procedures are described as well as those for generation of required data. Results for an application to two Division of the Huinong Irrigation District, Ningxia, in the upper Yellow River Basin, are presented and discussed including the comparison of the simulated demand with average allocations. Several scenarios for improvement are developed and a multi-criteria analysis is applied to their evaluation. The application to the Divisions 2 and 4 of the Huinong Irrigation District is shown. Results from several scenarios and their progressive implementation in time are analyzed showing positive impacts in farmers incomes and, mainly, on the environmental consequences of water savings.

Water saving in irrigation is a main issue in the Yellow River basin. Field studies were conducted in two areas. The Huinong system, Ningxia, in the upper reaches, where excess irrigation water is applied giving rise to waterlogging and salinity problems, and the Bojili system, Shandong, in the lower reaches of the river basin, where water availability is insufficient and salinity is related to drainage reuse. To control such problems, improved irrigation scheduling may play an important role. The irrigation scheduling simulation model ISAREG is used to evaluate the current schedules and to generate improved ones. It computes the capillary rise from the water table and deep percolation when excess water is applied, and considers the effects of salinity in crop evapotranspiration, crop water stress and yields, as well as the leaching requirements. The model has been previously calibrated and validated for North China. The model is explored interactively with surface irrigation simulation models to take into consideration the limitations imposed by the field systems concerning depths to be applied and irrigation performances. For Huinong, improvements consist in reducing the number of irrigations and adopting new calendars according to the depth of water table and the soil salinity conditions. Percolation could then be reduced from the current 60 % of the applied depths to only the volumes required for leaching. Water saving would represent more than 33 % and salinity could be controlled when also drainage would be improved. For Bojili, current schedules are appropriate and main issues concern deficit irrigation to cope with present water shortages. For both applications, it is concluded that effectiveness of irrigation scheduling improvements highly depend on required betterment in the basin irrigation systems mainly relative to land levelling, inflow discharges and field sizes.

In this study, a total of 118 Escherichia coli strains isolated from dogs (93) and cats (25) with urinary tract infection (UTI) were tested in a multiplex polymerase chain reaction for the presence of adhesin-encoding genes (pap, sfa, and afa), hemolysin encoding genes (hly), cytotoxic necrotizing factor 1 (cnf1) and aerobactin (aer) genes. Virulence gene frequencies detected in those isolates which had been randomly collected (68 canine strains) were: 43% pap, 57% sfa, 1% afa, 44% hly, 41% cnf1 and 34% aer. These frequencies were much higher in the remaining 50 hemolytic strains of either cat or dog origin. Virulence factor associations in the 80 hemolytic strains studied revealed that 50/80 simultaneously had two adhesin genes (pap and sfa) and two cytotoxin genes (hly and cnf1), and 15/80 in addition had the aer gene. The major structural subunit and antigenic determinant of P fimbriae of uropathogenic E. coli is PapA. Polymorphism in this subunit was studied by an F antigen-specific papA allele polymerase chain reaction in 51 canine and 22 feline pap positive E. coli strains. The most prevalent canine papA alleles were F10 (39%), F15 (37%) and F12 (35%). In feline strains F15 (50%) was more frequent, other allele frequencies were F12 (45%), F14 and F10 (27%) and F16 (23%). Only nine canine and two feline strains were negative for one of the 11 serologically defined F types of P fimbriae. Three copies of the pap operon were found in 16/51 canine and 9/22 feline UTI E. coli pap positive strains. In this study, we show that a particular combination of virulence genes appears with high frequency in dog and cat urinary tract E. coli strains (pap, sfa, hly, and cnf1). In spite of the more frequent presence of F10, F12 and F15 papA alleles in this virulence gene combination, the occurrence of different papA alleles in strains where up to three copies of the pap operon are present accounts for the observed P fimbriae diversity.

Traditionally, most irrigation practices in Southern Europe have been based on gravity-fed surface irrigation systems. Currently, these systems remain a relevant typology in the European Union (EU) member states of the Mediterranean areas, where it is often the only sustainable method for farmers due to the small size of agricultural holdings, their reduced capacity and readiness to invest and the low ratio between yield profits and irrigation costs. In the last several years, in response to European and national directives, surface irrigation has garnered increasing attention at the political and bureaucratic levels due to frequent criticisms of its postulated low efficiency and high water wastage. However, these systems commonly provide a number of ecosystem services and nature-based solutions that increase the positive externalities in different rural socio-ecological contexts and often have the potential to extend these services and provide solutions that are compatible with economical sustainability. This study aims to discuss the prospects for new practices and for the rehabilitation and modernization of the gravity-fed surface irrigation systems in EU Mediterranean areas to enhance water efficiency, thus gaining both economic advantages and environmental benefits. The difficulties, stimuli for improvements and peculiarities of the irrigation water management of four rural environments located in Italy, Spain and Portugal were analyzed and compared to the current state of the gravity-fed surface irrigation systems with hypothetical future improvements achievable by innovative technologies and practices. In these different case studies, the current gravity-fed surface irrigation systems have an obsolete regulatory structure; water-use efficiency is not a driving criterion for the management of the conveyance and distribution canal network, and farmers are not yet adequately encouraged to adopt more efficient gravity-fed irrigation practices. A continuous knowledge exchange is thus necessary for the interaction of all irrigation water managers and farmers to improve their eco-efficiency and to preserve and promote their cultural heritage across the entire water supply and delivery chains. We argue that the best way forward will require precisely targeted rehabilitation measures of gravity-fed surface irrigation systems based on the integrated use of decision support services, gate automation, remote and feedback controls and real-time flow optimization.

We have considered the thermal equilibrium in pre-protostellar cores in the approximation where the dust temperature is independent of interactions with the gas and where the gas is heated both by collisions with dust grains and ionization by cosmic rays. We have then used these results to study the stability of cores in the limit where thermal pressure dominates over magnetic field and turbulence. We find that for cores with characteristics similar to those observed, the gas and dust temperatures are coupled in the core interior. As a consequence, the gas temperature like the dust temperature decreases towards the center of these objects. The density structure computed taking into account such deviations from isothermality are not greatly different from that expected for an isothermal Bonnor-Ebert sphere. It is impossible in the framework of these models to have a stable equilibrium core with mass above about 5 solar masses and column density compatible with observed values. We conclude from this that observed high mass cores are either supported by magnetic field or turbulence or are already in a state of collapse. Lower mass cores on the other hand have stable states and we conclude that the much studied object B68 may be in a state of stable equilibrium if the internal gas temperature is computed in self-consistent fashion. Finally we note that in molecular clouds such as Ophiuchus and Orion with high radiation fields and pressures, gas and dust temperatures are expected to be well coupled and hence one expects temperatures to be relatively high as compared to low pressure clouds like Taurus., Comment: 11 pages, 6 figures. Astronomy & Astrophysics, in press

The performance of surface irrigation systems highly depends upon the design processbecause it relates to the appropriateness and precision of land leveling, field shape and dimensions,infiltration and inflow rates. However, the irrigation performance also depends on the farmer management,mainly in relation to land leveling maintenance, timeliness and application depth of every irrigation event,and his capability to overcome difficulties in supply such as uncertainty of deliveries and schedulingconstraints. Adopting a DSS methodology for both design and irrigation management could help making thebest decisions for systems design and operation. The DSS software SADREG has been developed mainly tosupport surface irrigation design, and has been tested for design in several countries and for differentirrigation methods and practices. Currently is being improved to support systems management, enablingfarmers advice in short term decisions. For management purposes, the model considers a fixed schedule(rigid water delivery scheme) or a dynamic one, where the irrigation dates and amounts are flexible, beingupdated by using the irrigation scheduling model ISAREG. For each irrigation event, SADREG simulatesseveral alternatives that satisfy the imposed constraints, and computes the application time, inflow-rate,irrigation unit size, tail water management and the correspondent performance indicators. Also estimates theyield impacts due to over- or under-irrigation, and selects the best management according decision-makerpriorities. This paper describes the DSS SADREG and its application to a case study in Fergana,Uzbekistan, illustrating the usefulness of this tool for water saving and environmentally friend issues.