What makes a citrus farmer go 'organic'? Empirical evidence from Spanish citrus farming

Organic farming is increasing its share of total world food output and receiving growing support from policymakers concerned with agricultural sustainability issues. This paper studies the characteristics of citrus farmers in the Spanish region of Valencia that affect their probability of becoming organic farmers. A fair understanding of these characteristics may help policymakers improve the design of agricultural policies aimed at supporting organic citrus practices. As regards the methodology, a probit model is estimated with information from a sample of conventional and organic citrus farmers obtained from a survey designed for a larger research project aimed at analysing Valencian citrus farming. Our main finding is that university education and agricultural professional training both increase the probability of becoming an organic farmer. Conversely, older farmers, farmers selling their production to foreign markets and those with larger farms and/or managing family farms are less likely to adopt organic citrus farming. The main policy implication is that, in order to support organic citrus production, more attention needs to be paid to improving farmers' technical training and education

High-throughput wide dynamic range procedure for the simultaneous quantification of nicotine and cotinine in multiple biological matrices using hydrophilic interaction liquid chromatography-tandem mass spectrometry

A straightforward, high-throughput method was developed and fully validated for the simultaneous determination of the specific tobacco biomarkers nicotine and its main metabolite cotinine in a wide dynamic range and supporting the most common human biological matrices (urine, oral fluid and hair). Sample preparation was performed inside the very HPLC injection vials by pipetting 0.5 mL of the liquid samples, deuterated internal standards in alkaline solution and dichloromethane as extraction solvent. Solid samples (i.e. around 10 mg hair) were first submitted to alkaline digestion in the HPLC vials and processed accordingly. The organic phase (reached through the upper aqueous layer) was directly injected without further treatment. Instrumental analysis was performed using hydrophilic interaction (HILIC) ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Total chromatographic time was 2 min. The method covers a wide dynamic range making it fit-for-purpose for the analysis of samples covering entire populations, irrespective of the level of exposure or tobacco use. Calibration curves (r 2 > 0.995) covered the range 1-2000 ng/mL (or 0.05-100 ng/mg hair) for nicotine and 0.1-2000 ng/mL (or 0.005-100 ng/mg hair) for cotinine. Within-run and between-run precision and accuracy were typically below 10 %, and always below 20 % at the lower limit of quantification. The method was successfully applied to the analysis of samples from different projects involving multiple matrices

Food Allergy Knowledge, Attitudes and Practices: A Pilot Study of the General Public and Food Handlers

Objective: We have assessed the factors that might improve the free food allergen at the restaurants. In addition, we have compared food handlers knowledge with the general public knowledge about food allergens. Design: Cross-sectional, via questionnaires. Participants: A total of 182 participants (80 food handlers and 102 of general public). Main Outcome Measures: Dependent variables: Food allergy knowledge, attitudes and practices. Analysis: The analysis of variance (ANOVA) and independent t-test. Questionnaires were hand coded and data was analyzed using Statistical Package for Social Sciences (SPSS) version 19.0. Results: The survey showed that food handlers and general public had some knowledge on the issue, a major proportion of both group do not believe the meals produced in restaurants are safe in terms of food allergies. Conclusions and Implications: Allergic people must stay on the alert, questioning the place where they are going to have their meals in terms of the ingredients used, verifying whether the food is really free of allergens. This study can be used by restaurants to develop food allergy policies

Future teachers' digital competence: what is the perception of current students teachers'?

En el momento actual, el rol de los docentes resulta fundamental para capacitar a los estudiantes utilizando todas las potencialidades que ofrecen las TIC. Los docentes necesitan disponer, no solo de una alfabetización digital básica, sino también ser capaces de integrarlas en sus prácticas didácticas, y para ello, su formación inicial resulta fundamental. El principal objetivo de este estudio es explorar la competencia digital de futuros docentes a partir de su autopercepción, un factor clave para su posterior desempeño. Para ello, una muestra de 149 estudiantes universitarios de educación respondieron a un cuestionario de autopercepción diseñando siguiendo los estándares de ISTE. Según los resultados, la mayoría de los futuros docentes disponen de un nivel alto de competencia digital docente (especialmente en habilidades digitales básicas más que en su aplicación didáctica), asimismo se evidenciaron ciertas diferencias significativas en cuanto a la edad, en el área de las habilidades digitales básicas.Nowadays, the role of teachers is crucial in empowering students with the advantages of ICT. Teachers are required not only to become basically digitally literate, but they should also be able to integrate technology into their teaching, and initial teacher education is one of the most important factors for this purpose. The main aim of this study was to explore the student teachers’ digital competence through their own self-perceptions, a key factor for their future performance. For this purpose, a sample of 149 student teachers’ completed a self-perception questionnaire constructed in accordance with ISTE standards. The results show that most student teachers have a high level of self-perceived digital competence (better basic digital skills that in didactic use of ICT). However, there were significant differences in basic digital skills according to the age of student teachers

Partial replacement of sodium in meat and fish products by using magnesium salts. A review

[EN] Sodium intake exceeds the nutritional recommendations in most industrialized countries becoming one concern for public health. This elimination or reduction is not simple due to its role in final food sensory, quality and safety. The aim of this work is to review the possibilities of magnesium ion, due to its healthy properties, to become a partial substitute of sodium in the production of fish and meat products, and a particular case for Spanish dry-cured ham and loin. Magnesium diffusion into different muscle based foods such as ham or loin, and its effect in the most important characteristics of the final product (microbiology, physico-chemical and sensory properties) has been analyzed. Results show that magnesium has more difficulty to penetrate inside the muscle and slightly modifies the water-holding capacity of proteins, their solubility and the enzymatic activity. Salty taste, bitterness and off-flavor are the most affected characteristics. However, these effects could be compensated by using longer post-salting periods and by employing masking agents. It is possible to reduce the sodium content in fish and meat products using magnesium as one of the ingredients, allowing to obtain new products with similar physicochemical characteristics and safety conditions.Grant AGL2007-65379-C02-01 & 02 and AGL2010-16305 from Ministry of Science and Innovation (Spain) and FEDER funds are acknowledged.Barat Baviera, JM.; Pérez-Esteve, É.; Aristoy, MC.; Toldra, F. (2013). Partial replacement of sodium in meat and fish products by using magnesium salts. A review. Plant and Soil. 368(1-2):179-188. https://doi.org/10.1007/s11104-012-1461-7S1791883681-2Albarracín W, Sánchez IC, Grau R, Barat JM (2011) Salt in food processing; usage and reduction: a review. Int J Food Sci Technol 46:1329–1336Aliño M, Grau R, Baigts D, Barat JM (2009a) Influence of sodium replacement on the salting kinetics of pork loin. J Food Eng 95:551–557Aliño M, Grau R, Toldrá F, Blesa E, Pagán MJ, Barat JM (2009b) Influence of sodium replacement on physicochemical properties of dry-cured loin. Meat Sci 83:423–430Aliño M, Grau R, Toldrá F, Barat JM (2010a) Physicochemical changes in dry-cured hams salted with potassium, calcium and magnesium chloride as a partial replacement for sodium chloride. Meat Sci 86:331–336Aliño M, Grau R, Toldrá F, Blesa E, Pagán MJ, Barat JM (2010b) Physicochemical properties and microbiology of dry-cured loins obtained by partial sodium replacement with potassium, calcium and magnesium. Meat Sci 85:580–588Aliño M, Grau R, Fuentes A, Barat JM (2010c) Characterisation of pile salting with sodium replaced mixtures of salts in dry-cured loin manufacture. J Food Eng 97:434–439Aliño M, Grau R, Fuentes A, Barat JM (2010d) Influence of low-sodium mixtures of salts on the post-salting stage of dry-cured ham process. J Food Eng 99:198–205Andrés AI, Cava R, Ventanas J, Thovar V, Ruiz J (2004) Sensory characteristics of Iberian ham: influence of salt content and processing conditions. Meat Sci 68:45–51Andrés A, Barat JM, Grau R, Fito P (2007) Principles of drying and smoking. In: Toldrá F, Hui YH, Nip W, Sebranek JG, Stahnke L, Silveira EF, Talon R (eds) Handbook of fermented meat and poultry. IFT Press – Blackwell Publishing, Ames, pp 37–50Armenteros M, Aristoy MC, Toldrá F (2009a) Effect of sodium, potassium, calcium and magnesium chloride salts on pork muscle proteases. Eur Food Res Tech 229:93–98Armenteros M, Aristoy MC, Barat JM, Toldrá F (2009b) Biochemical and sensory properties of dry-cured loins as affected by partial replacement of sodium by potassium, calcium and magnesium. 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On the number of kk-cycles in the assignment problem for random matrices

We continue the study of the assignment problem for a random cost matrix. We analyse the number of $k$-cycles for the solution and their dependence on the symmetry of the random matrix. We observe that for a symmetric matrix one and two-cycles are dominant in the optimal solution. In the antisymmetric case the situation is the opposite and the one and two-cycles are suppressed. We solve the model for a pure random matrix (without correlations between its entries) and give analytic arguments to explain the numerical results in the symmetric and antisymmetric case. We show that the results can be explained to great accuracy by a simple ansatz that connects the expected number of $k$-cycles to that of one and two cycles.Comment: To appear in Journal of Statistical Mechanic

Secondhand smoke in outdoor settings: smokers' consumption, non-smokers' perceptions, and attitudes towards smoke-free legislation in Spain

Objective: to describe where smokers smoke outdoors, where non-smokers are exposed outdoors to secondhand smoke (SHS), and attitudes towards smoke-free outdoor areas after the implementation of national smoke-free legislation. Design: this cross-sectional study was conducted between June 2011 and March 2012 (n=1307 participants). Setting: Barcelona Participants: representative, random sample of the adult (≥16 years) population. Primary and secondary outcomes: proportion of smoking and prevalence of exposure to SHS in the various settings according to type of enclosure. Percentages of support for outdoor smoke-free policies according to smoking status. Results: smokers reported smoking outdoors most in bars and restaurants (54.8%), followed by outdoor places at work (46.8%). According to non-smokers, outdoor SHS exposure was highest at home (42.5%) and in bars and restaurants (33.5%). Among non-smoking adult students, 90% claimed exposure to SHS on university campuses. There was great support for banning smoking in the majority of outdoor areas, which was stronger among non-smokers than smokers. Over 70% of participants supported smoke-free playgrounds, school and high school courtyards, and the grounds of healthcare centres. Conclusions: extending smoking bans to selected outdoor settings should be considered in further tobacco control interventions to protect non-smokers from SHS exposure and to establish a positive model for youth. The majority of public support for some outdoor smoke-free areas suggests that it is feasible to extend smoking bans to additional outdoor settings

Role of Potassium Permanganate Ethylene on Physicochemical Properties, during Storage of Five Different Tomato Cultivars

Although tomatoes should be ripened at room temperature to obtain the best flavour, the majority of consumers who preserve food at home store tomatoes in the fridge for 4-7 days and some people even keep tomatoes for up to 3 weeks in these conditions. In the present work the effects of storage time and potassium permanganate ethylene absorber sachets under refrigerated conditions (similar to those used by consumers who preserve tomatoes at home) on physicochemical properties, ascorbic acid content and antioxidant capacity of five tomato cultivars (Cherry, Cherry pera, Rama, Raf and Pera) were studied. After 25 days storage at 4±2 °C an increase in fruit pH was observed for the five cultivars without and with ethylene absorber sachets. The increase in pH was paralleled by a decrease in titratable acidity. The degradation of ascorbic acid during storage time with and without ethylene absorber sachets followed a first-order kinetic model. In general, the percent loss of ascorbic acid and antioxidant capacity measured with TEAC and ORAC methods was significantly lower in tomatoes stored with ethylene absorber sachets as compared to tomatoes preserved without these. In addition, a positive correlation was found between ORAC and TEA

A New Perylene Salt: Diperylenium(1+) Bis[quinoxaline-2,3-dithiolato(2 -)-S,S']cuprate(III)

A new perylene salt, (C20H12)2[Cu(C8H4N2S2)2],(per)2[Cu(qdt)2], has been prepared by electrocystallization and characterized by single-crystal X-ray diffraction. The crystal structure consists of tetramerized stacks of perylene species along the c axis, with three crystallographically independent interplanar distances, 3.50(1), 3.42(1) and 3.55(1)A. These tetramers are flanked by a centrosymmetrically related pair of [Cu(qdt)2]- anions

Recomanacions per als puzles en l'aprenentatge de la construcció

Aquesta comunicació presenta recomanacions d’utilitat per a la realització d’activitats puzle dirigides a l’aprenentatge de la construcció a l’arquitectura. Aquestes recomanacions es basen en l’experiència d’utilitzar l’activitat puzle en classes de construcció del Departament de Construccions Arquitectòniques I (CA1) de l’Etsab, UPC. Aquestes activitats s’han dut a terme en assignatures de segon curs (Construcció 1); tercer curs (Construcció IV) i Postgrau (Màster universitari en Tecnologia a l’Arquitectura). Aquests puzles han incorporat variacions respecte la tècnica puzle convencional. N’hi ha hagut sobre detalls constructius d’edificis, sobre solucions davant de conflictes reals a l’obra, d’externs... Durant aquests puzles s’han recollit diversos indicadors: pretests i posttests, enquestes de satisfacció, temps de dedicació, fitxes d’aprenentatge... Analitzant aquests indicadors és possible: a) confirmar que l’alumnat valora positivament aquesta activitat; i b) recollir i ordenar l’experiència acumulada mitjançant les recomanacions que es presenten en aquesta comunicació.Peer Reviewe