124 research outputs found

    Economic evaluation of mechanical harvesting of lemons

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    [EN] Several hypotheses regarding hand and mechanical harvesting have been analysed, in order to estimate the economic possibilities for the mechanical harvesting of lemons taking into account the current availability of technology. We considered several detachment options under experimental conditions; only yellow detachment has been considered for mechanical harvesting, because the sensitivity to the impacts is lower and mechanical detachment was high (80%). Price changes throughout the season were also considered. Total harvest cost is an average of the cost of mechanical harvesting (80%) and the cost of manually harvesting remaining fruit (20%), plus the cost of handling the mechanical harvested fraction. This cost ranges between 0.031 and 0.058 € kg-1 for outputs between 20 and 60 t ha-1, respectively, which is always lower than harvesting by hand (0.065 € kg-1). A Monte Carlo approach was used to study the sensitivity of the results, and Value at Risk (VaR) calculated. The analysis showed that the mechanical harvesting margin is c0.020 € kg-1 higher than the hand harvesting margin, and the output dispersion is higher in March. The VaR analysis showed that at 10% there was no risk that the hand margin is higher than the mechanical margin; at 5% the risk is very low and only for March harvesting. Mechanical harvesting represents a good economic option compared to hand harvesting, since it can increase farmer income by between 400 and 1200 € ha-1.This work was funded by Consejería de Agricultura y Agua de la Región de Murcia and by INIA and FEDER funds (project no. RTA2014-00025-C05-02).Brotons-Martínez, JM.; Martín-Górriz, B.; Torregrosa, A.; Porras, I. (2018). Economic evaluation of mechanical harvesting of lemons. Outlook on Agriculture. 47(1):44-50. https://doi.org/10.1177/0030727018762657S4450471Bordas, M., Torrents, J., Arenas, F. J., & Hervalejo, A. (2012). HIGH DENSITY PLANTATION SYSTEM OF THE SPANISH CITRUS INDUSTRY. Acta Horticulturae, (965), 123-130. doi:10.17660/actahortic.2012.965.15Burns, J. K., Roka, F. M., Li, K.-T., Pozo, L., & Buker, R. S. (2006). Late-season `Valencia’ Orange Mechanical Harvesting with an Abscission Agent and Low-frequency Harvesting. HortScience, 41(3), 660-663. doi:10.21273/hortsci.41.3.660Grafiadellis, I., Mattas, K., Maloupa, E., Tzouramani, I., & Galanopoulos, K. (2000). An Economic Analysis of Soilless Culture in Gerbera Production. HortScience, 35(2), 300-303. doi:10.21273/hortsci.35.2.300Manera, F. J., Brotons, J. M., Conesa, A., & Porras, I. (2012). Influence of temperature on the beginning of degreening in lemon peel. Scientia Horticulturae, 145, 34-38. doi:10.1016/j.scienta.2012.07.021Moreno, R., Torregrosa, A., Moltó, E., & Chueca, P. (2015). Effect of harvesting with a trunk shaker and an abscission chemical on fruit detachment and defoliation of citrus grown under Mediterranean conditions. Spanish Journal of Agricultural Research, 13(1), e0206. doi:10.5424/sjar/2015131-6590Roka, F. M., & Hyman, B. R. (2012). MECHANICAL HARVESTING OF SWEET ORANGES FOR JUICE PROCESSING. Acta Horticulturae, (965), 241-243. doi:10.17660/actahortic.2012.965.32Sanders, K. F. (2005). Orange Harvesting Systems Review. Biosystems Engineering, 90(2), 115-125. doi:10.1016/j.biosystemseng.2004.10.006A. Torregrosa, I. Porras, & B. Martín. (2010). Mechanical Harvesting of Lemons (cv. Fino) in Spain Using Abscission Agents. Transactions of the ASABE, 53(3), 703-708. doi:10.13031/2013.30062Wagner, H. M. (1995). Global Sensitivity Analysis. Operations Research, 43(6), 948-969. doi:10.1287/opre.43.6.948J. D. Whitney. (1999). FIELD TEST RESULTS WITH MECHANICAL HARVESTING EQUIPMENT IN FLORIDA ORANGES. Applied Engineering in Agriculture, 15(3), 205-210. doi:10.13031/2013.576

    Effects of vessel traffic on relative abundance and behaviour of cetaceans : the case of the bottlenose dolphins in the Archipelago de La Maddalena, north-western Mediterranean sea

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    Acknowledgements This study was part of the Tursiops Project of the Dolphin Research Centre of Caprera, La Maddalena. Financial and logistical support was provided by the Centro Turistico Studentesco (CTS) and by the National Park of the Archipelago de La Maddalena. We thank the Natural Reserve of Bocche di Bonifacio for the support provided during data collection. The authors thank the numerous volunteers of the Caprera Dolphin Research Centre and especially Marco Ferraro, Mirko Ugo, Angela Pira and Maurizio Piras whose assistance during field observation and skills as a boat driver were invaluable.Peer reviewedPostprin

    Evaluation of the potential index model to predict habitat suitability of forest species: the potential distribution of mountain pine (Pinus uncinata) in the Iberian peninsula

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    Characterization of the suitability or potentiality of a territory for forest tree species is an important source of information for forest planning and managing. In this study, we compared a relatively simple methodology to generate potential habitat distribution areas that has been traditionally used in Spain (the potential index model) with a statistical modelling approach (generalized linear model). We modelled the potential distribution of mountain pine (Pinus uncinata) in the Iberian peninsula as a working example. The potential index model generated a map of habitat suitability according to the values of an index of potentiality, whose distribution has usually divided into four categories based on quartiles (from optimum to low suitability). Considering all values of the index of potentiality as presences of mountain pine resulted in a low to moderate degree of agreement between the potential index model and the generalized linear model according to the kappa coefficient. Using the cut-off value of the index of potentiality that maximized the degree of agreement between both modelling approaches resulted in a substantial similarity between the maps of the predicted distribution of mountain pine. This cut-off value did lie in the upper-third quartile of the potential index distribution (high suitability category), and roughly coincided with the upper 30th percentile. The use of statistical techniques, which have proved to be powerful and versatile for species distribution modelling, is recommended. However, the potential index model, together with the adjustments proposed here, could be a reasonably simple methodology to predict the potential distribution of forest tree species that forest managers should take into account when evaluating forestation and afforestation projects

    Self-reported smoking cessation activities among Swiss primary care physicians

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    ABSTRACT: BACKGROUND: Individual counselling, pharmacotherapy, and group therapy are evidence-based interventions that help patients stop smoking. Acupuncture, hypnosis, and relaxation have no demonstrated efficacy on smoking cessation, whereas self-help material may only have a small benefit. The purpose of this study is to assess physicians' current clinical practice regarding smokers motivated to stop smoking. METHODS: The survey included 3385 Swiss primary care physicians. Self-reported use of nine smoking cessation interventions was scored. One point was given for each positive answer about practicing interventions with demonstrated efficacy, i.e. nicotine replacement therapy, bupropion, counselling, group therapy, and smoking cessation specialist. No points were given for the recommendation of acupuncture, hypnosis, relaxation, and self-help material. Multivariable logistic analysis was performed to identify factors associated with a good practice score, defined as >1. RESULTS: The response rate was 55%. Respondents were predominately over the age of 40 years (88%), male (79%), and resided in urban areas (74%). Seventeen percent reported being smokers. Most of the physicians prescribed nicotine replacement therapy (84%), bupropion (65%), or provided counselling (70%). A minority of physicians recommended acupuncture (26%), hypnosis (8%), relaxation (7%), or self-help material (24%). A good practice score was obtained by 85% of respondents. Having attended a smoking cessation training program was the only significant predictor of a good practice score (odds ratio: 6.24 , 95% CI 1.95-20.04). CONCLUSION: The majority of respondents practice recommended smoking cessation interventions. However, there is room for improvement and implementing an evidence-based smoking cessation-training program could provide additional benefit

    Spatial heterogeneity of habitat suitability for Rift Valley fever occurrence in Tanzania: an ecological niche modelling approach

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    Despite the long history of Rift Valley fever (RVF) in Tanzania, extent of its suitable habitat in the country remains unclear. In this study we investigated potential effects of temperature, precipitation, elevation, soil type, livestock density, rainfall pattern, proximity to wild animals, protected areas and forest on the habitat suitability for RVF occurrence in Tanzania. Presence-only records of 193 RVF outbreak locations from 1930 to 2007 together with potential predictor variables were used to model and map the suitable habitats for RVF occurrence using ecological niche modelling. Ground-truthing of the model outputs was conducted by comparing the levels of RVF virus specific antibodies in cattle, sheep and goats sampled from locations in Tanzania that presented different predicted habitat suitability values. Habitat suitability values for RVF occurrence were higher in the northern and central-eastern regions of Tanzania than the rest of the regions in the country. Soil type and precipitation of the wettest quarter contributed equally to habitat suitability (32.4% each), followed by livestock density (25.9%) and rainfall pattern (9.3%). Ground-truthing of model outputs revealed that the odds of an animal being seropositive for RVFV when sampled from areas predicted to be most suitable for RVF occurrence were twice the odds of an animal sampled from areas least suitable for RVF occurrence (95% CI: 1.43, 2.76, p < 0.001). The regions in the northern and central-eastern Tanzania were more suitable for RVF occurrence than the rest of the regions in the country. The modelled suitable habitat is characterised by impermeable soils, moderate precipitation in the wettest quarter, high livestock density and a bimodal rainfall pattern. The findings of this study should provide guidance for the design of appropriate RVF surveillance, prevention and control strategies which target areas with these characteristics

    Lipid-lowering drugs in ischaemic heart disease : a quasi-experimental uncontrolled before-and-after study of the effectiveness of clinical practice guidelines

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    Background: Cardiovascular diseases(CVD), specifically ischaemic heart disease(IHD), are the main causes of death in industrialized countries. Statins are not usually prescribed in the most appropriate way. To ensure the correct prescription of these drugs, it is necessary to develop, disseminate and implement clinical practice guidelines(CPGs), and subsequently evaluate them. The main objective of this study is to evaluate the effectiveness of the implementation of consensual Lipid-lowering drugs (LLD) prescription guidelines in hospital and primary care settings, to improve the control of Low-Density Lipoprotein Cholesterol (LDL-C) levels in patients with IHD in the Terres de l'Ebre region covered by the Catalonian Health Institute. Secondary bjectives are to assess the improvement of the prescription profile of these LLDs, to assess cardiovascular morbimortality and the professional profile and participant centre characteristics that govern the control of LDL-C. Methods/Design Design: Quasi-experimental uncontrolled before and after study. The intervention consists of the delivery of training strategies for guideline implementation (classroom clinical sessions and on-line courses) aimed at primary care and hospital physicians. The improvement in the control of LDL-C levels in the 3,402 patients with IHD in our territory is then assessed. Scope: Primary care physicians from 11 basic health areas(BHAs) and two hospital services (internal medicine and cardiology). Sample: 3,402 patients registered with IHD in the database of the Catalan Institute of Health(E-cap) before December 2008 and patients newly diagnosed during 2009-2010. Variables: Percentage of patients achieving good control of LDL-C, measured in milligrams per decilitre. The aim of the intervention is to achieve levels of LDL-C < 100 mg/dl in patients with IHD. Secondary variables measure type and time of diagnosis of IHD, type and dose of prescribed cholesterol-lowering drugs, level of physician participation in training activities and their professional profile. Discussion: The development of prescription guidelines previously agreed by various medical specialists involved in treating IHD patients have usually improved drug prescription. The guideline presented in this study aims to improve the control of LDL-C by training physicians through presential and on-line courses on the dissemination of this guideline, and by providing feedback on their personal results a year after this training intervention

    Effectiveness of skills-based training using the Drink-less package to increase family practitioner confidence in intervening for alcohol use disorders

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    BACKGROUND: Misuse of alcohol is second only to tobacco as a leading cause of preventable death in Australia. There is an opportunity in family practice to detect problems and intervene with people at risk of alcohol-related harm before complications occur. However, family practitioners (FPs) report low levels of confidence in managing patients with drinking problems. The aim of this study was to determine whether the interactive training session using the 'Drink-less' package led to improvement in FPs' self-reported level of confidence in detecting and providing interventions for risky alcohol consumption. METHOD: FPs in urban and rural New South Wales were invited to training sessions in their local area. An introductory overview preceded a practical skills- based session, using the Drink-less package. Participants completed before and after evaluation forms. RESULTS: While 49% (CI 43 – 55) of the attending FPs indicated at baseline that they felt confident in identifying at-risk drinkers, this proportion rose to 90% (95% CI: 87 – 93) post-session, and they also reported increases in confidence from 36% (95% CI: 31 – 41) to 90% in their ability to advise patients. Urban FPs reported lower levels of confidence than rural FPs, both pre- and post-session. CONCLUSION: Training sessions in the Drink-less intervention resulted in increased self-reported confidence in detection and brief intervention for alcohol problems. Further research is needed to determine the duration of this effect and its influence on practice behaviour

    Therapeutic implications of selecting the SCORE (European) versus the D'AGOSTINO (American) risk charts for cardiovascular risk assessment in hypertensive patients

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    Background: No comparisons have been made of scales estimating cardiovascular mortality and overall cardiovascular morbidity and mortality. The study objectives were to assess the agreement between the Framingham-D'Agostino cardiovascular risk (CVR) scale and the chart currently recommended in Europe (SCORE) with regard to identification of patients with high CVR, and to describe the discrepancies between them and the attendant implications for the treatment of hypertension and hyperlipidaemia. Methods: A total of 474 hypertensive patients aged 40-65 years monitored in primary care were enrolled into the study. CVR was assessed using the Framingham-D'Agostino scale, which estimates the overall cardiovascular morbidity and mortality risk, and the SCORE chart, which estimates the cardiovascular mortality risk. Cardiovascular risk was considered to be high for values ≥ 20% and ≥ 5% according to the Framingham-D'Agostino and SCORE charts respectively. Kappa statistics was estimated for agreement in classification of patients with high CVR. The therapeutic recommendations in the 2007 European Guidelines on Cardiovascular Disease Prevention were followed. Results

    From descriptive to predictive distribution models: a working example with Iberian amphibians and reptiles

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    BACKGROUND: Aim of the study was to identify the conditions under which spatial-environmental models can be used for the improved understanding of species distributions, under the explicit criterion of model predictive performance. I constructed distribution models for 17 amphibian and 21 reptile species in Portugal from atlas data and 13 selected ecological variables with stepwise logistic regression and a geographic information system. Models constructed for Portugal were extrapolated over Spain and tested against range maps and atlas data. RESULTS: Descriptive model precision ranged from 'fair' to 'very good' for 12 species showing a range border inside Portugal ('edge species', kappa (k) 0.35–0.89, average 0.57) and was at best 'moderate' for 26 species with a countrywide Portuguese distribution ('non-edge species', k = 0.03–0.54, average 0.29). The accuracy of the prediction for Spain was significantly related to the precision of the descriptive model for the group of edge species and not for the countrywide species. In the latter group data were consistently better captured with the single variable search-effort than by the panel of environmental data. CONCLUSION: Atlas data in presence-absence format are often inadequate to model the distribution of species if the considered area does not include part of the range border. Conversely, distribution models for edge-species, especially those displaying high precision, may help in the correct identification of parameters underlying the species range and assist with the informed choice of conservation measures
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