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Agricultural innovation implies sharing information between researchers and farmers. Acknowledging the value of the other partner’s knowledge is a preliminary step to facilitate agricultural intera...

A sample group of 119 farmers from a semi-arid district of Madrid was interviewed to determine the knowledge of individuals about soil conservation and management. Farmers commonly identify physical factors in the landscape that are visually recognizable and those chemical factors that clearly affect productivity. Often, factors, such as salinity or pH that require laboratory analysis, are less readily identified. Farmer knowledge of soils is influenced by their main source of income, gender, education and age. Although there is a high degree of correspondence between scientific and traditional knowledge of soil, some gaps have been identified, notably those related to erosion. Key steps identified for promoting the adoption of sustainable soil management practices to farmers were as follows: involvement of public institutions, the need for increased agricultural prices and an improvement in training and public awareness. Farmers were aware of their own limitations and demanded capacity building, technical and policy support.

Silicon photomultipliers are devices widely used and have direct applications in multiple scientific fields. Currently, the Universidad Antonio Nariño, Colombia, finance the research project Characterization of the coherent structures in the edge region of the plasma column in the TCABR tokamak using Langmuir probes in collaboration with Universidade de Sao Paulo, Brazil. In this project, we research plasma, and recently, we proposed a silicon photomultiplier to measure X-ray emissions from the plasma column. In this application, we have to know specific characteristics of silicon photomultiplier in behavior controlled conditions to establish its possible changes during exposure to radiation of plasma; one of silicon photomultiplier characteristics more important is gain due to its temperature dependence that generates disturbances on its response. To characterize the silicon photomultiplier in controlled conditions, we developed an analog integral proportional temperature automatic control system for the control of a silicon photomultiplier characterization setup that lets temperature variations from room temperature to 50°C reaching reference temperature in 1 minute with a steady state error less than 2% and overshoot of 5.53%.

Yucca is a genus of perennial shrubs and trees (family Asparagaceae subfamily Agavoideae) native to hot, dry parts of America and the Caribbean. Yucca filifera is an important plant with a wide range of uses. In November 2017, in Pena de Bernal, Queretaro (20°44′21.45″ N; 99°56′20.13″ W), leaf dieback was observed in natural areas, affecting up to 15% of plants. The disease started with large brown spots on the apex of leaves (in some cases on one side) that dried out. Lesions were covered with black conidiomata scattered throughout. The disease gradually advanced to the leaf base. The disease does not cause death but affects the valuable leaves and indirectly affects plant development. Whole leaf blades at five different survey sites were collected, with three leaf blades per site. Fractions were cut from symptomatic tissue, including healthy tissue, surface disinfested with 2% NaOCl for 2 min, rinsed in sterile distilled water (SDW), and placed in Petri dishes with three filter paper discs soaked with SDW. They were incubated under fluorescent light at 25°C with 12-h light/dark. After 4 days, conidiomata were examined under both an optical microscope and field emission SEM. Conidia were collected from conidial masses exuding from freshly exposed pycnidia. Masses of conidia were collected using a sterilized needle, placed into 1.5-ml tubes with SDW, spread on PDA Petri dishes, and incubated at 25°C. The presumptive causal agent was isolated; 5 × 5-mm sections were cut from the margin of infected tissue and disinfected, placed on PDA Petri dishes, and incubated. Cultures of similar morphology were consistently recovered from both masses of conidia and infected tissue on PDA. Twenty monoconidial isolates were obtained. A representative one was selected for morphological characterization, multilocus phylogenetic analysis, and pathogenicity tests. Growth conditions were 25°C with 12-h light/dark. Cultures were measured and photographed after 2 weeks; appearance was noted after 2 to 3 weeks. On the host, conidiomata pycnidial, black, immersed, globose, unilocular, 365 to 537 × 270 to 334 μm; ostiole central, nonpapillate, up to 37.8 μm diameter, exuding a hyaline conidial cirrhus. Conidiophores lining the inner cavity, reduced to conidiogenous cells, hyaline, smooth, subcylindrical. Conidia hyaline, guttulate, cylindrical to obclavate, three-septate, conidial size (100 conidia) of 82.2 to 94.5 × 7.7 to 9.5 μm; apex acutely rounded; conidial base truncate, appendages absent. Surface ornamentation of conidia, striate with thin parallel ridges. Culture characteristics: colonies on PDA after 2 weeks; surface near light gray, moderate aerial mycelium; margin irregular, whitish; conidiomata black; reverse uncolored. The rDNA ITS was sequenced (MN509001). The sequence was compared with GenBank and showed 98.17 and 98.05% identity with Kellermania macrospora KF766178.1 and KF777165.1, respectively. The fungus was identified as K. macrospora (Crous et al. 2013; Slippers et al. 2013). To confirm Koch’s postulates, Y. filifera plants (∼3 years) were cut and rooted in pots with sterile substrate and kept confined for 6 months before inoculation. A suspension was prepared from 1-week-old culture (MN509001) in SDW at 8 × 10³ conidia/ml containing 0.02% Tween 20. The suspension was sprayed on healthy leaves of 10 plants; SDW with 0.02% Tween 20 was used as a control (three plants). Plants were covered for 48 h with plastic bags to maintain 100% RH. Bags were removed, and plants were maintained at 25 ± 5°C, 65% RH. Lesions developed within 25 days of inoculation; control plants remained symptomless. The fungus recovered from inoculated tissues showed the same morphological characteristics as the isolate used in inoculations. K. macrospora has been reported on Agave sp. (Minnis et al. 2012) and Yucca rostrata (Crous et al. 2013). The leaf dieback on Y. filifera caused by K. macrospora is the first report from Mexico. Yucca leaf dieback has not been reported elsewhere. It appears to be newly emerging in Mexico. It is recommended to establish a pruning scheme to eliminate affected leaves to reduce inoculum levels.

In this paper, we calculate optimal cell compositions and voltage-matching considerations for independently connected junctions, such as those proposed for microsystem-enabled photovoltaic modules. The calculations show that designs using voltage-matched independent junctions can achieve better yearly efficiency across temperature and spectrum than traditional monolithic cells. Voltage matching is shown to be relatively insensitive to temperature and spectrum but is dependent on open-circuit voltage as a measure of cell efficiency. If the efficiencies and, hence, maximum power point voltages are known a priori , voltage matching can usually yield yearly efficiencies of 98–99% of the efficiency of a system with each cell operating at its own maximum power point.

[1] We present a statistical analysis on the plasmaspheric mass density derived from the field line resonance (FLR) observations by the Mid-continent MAgnetoseismic Chain (McMAC). McMAC consists of nine stations in the United States and Mexico along the 330° magnetic longitude, spanning L-values between 1.5 and 3.4. Using the gradient method and an automated procedure for FLR detection, we studied a full year of McMAC observations between July 2006 and June 2007. We find that the rate of FLR detection can reach as high as 56% around local noon at L = 2.7, and the detection rates at higher and lower L-values decline due to the occasional presence of the plasmapause and weaker FLR signals, respectively. At L-values between 1.8 and 3.1, the inferred equatorial plasma mass density follows the L-dependence of L−4. By comparing the mass density with the electron density, we found that the ion mass gradually decreased from 1.7 amu at L = 1.8 to 1 amu at L = 3.1. The plasma mass density exhibits an annual variation that maximizes in January, and at L = 2.4 the ratio between January and July densities is 1.6. Our observations also show a local time dependence of plasmaspheric mass density that stays steady in the morning and rises postnoon, a phenomenon that may be attributed to the equatorial ionization anomaly as a part of the plasma neutral coupling at low latitude.

Tissue inhibitor of metalloprotease 4 (TIMP4) contributes to poor prognosis in breast and other tumours. However, the mechanisms of how TIMP4 influences breast cancer cell behaviour are unknown. Our aim was to explore the signalling pathways modulated by TIMP4 in breast cancer cells. Human recombinant TIMP4 was added to MCF7 breast cancer cells and RNASeq was performed. TIMP4 RNASeq results were validated by RT-PCR. Network analyses of TIMP4-exposed cells showed that ER-α, HIF1A and TGF-β signalling were activated, whereas FOXO3 signalling was downregulated. ER-α protein levels were increased and concordantly, promoters of TIMP4-upregulated genes were significantly enriched in oestrogen-binding sites. We concluded that TIMP4 modulates multiple signalling pathways relevant in cancer in MCF7 cells, including the ER-α cascade.

A ''mold-less'' method for rapid prototyping spherical microlenses using the surface tension of a transparent, temperature sensitive polymer is presented. The lens size can be varied with the volume of the polymer dispensed, with a diameter range of [email protected] The focal length can be varied with the deposition/curing temperature, and can have values in the range of 2-25mm. Mechanical profilometry and custom software was used to measure the lens profile. Parameters such as curvature, focal length, diameter, contact angle, and F-number were extracted from the measurements. Finally, an empirical model that predicts these variables as a function of temperature and volume deposited is proposed.

Currently, application of nanotechnology in biomedicine contributes in progress related to the diagnosis and treatment of breast cancer. Our research group is working on the development of an innovative technology to promote the selective ablation of breast cancer in its early stages by the use of high frequency magnetic fields assisted by magnetic nanoparticles. This study is focused to show experimentally the pass of a nanoprobe ”Magnetic nanoparticle-antibody anti cerbB- 2” from the vascular endothelium to the neoplastic epithelium. A nanoprobe was developed by the covalent union of fluorescent magnetic nanoparticles and anti cerbB- 2 Mab by carbodiimide method. A breast cancer model induced in rats with N-methyl, N-nitrosourea (MNU) was employed. Systemic infusion of nanoprobe was conducted and guided to the cancerous tissue by an external magnet positioned in the tumor region. Dissection and histopathological characterization of tumor as well as the detection of nanoprobe by an immunofluorescence assay were performed. The results indicate that the induced tumor corresponds to an invasive ductal carcinoma, and immunofluorescence analysis showed the presence of the nanoprobe in tumoral ducts, which is indicative of the direct path of the nanoprobe into the tumor and its binding to c-erbB-2 expressed in the cytoplasmic membrane of tumor cells.

Leather-like composites were prepared by addition of chemically modified short leather fibers (SLF) into a plasticized polyvinyl chloride (pPVC) matrix. The fibers were subjected to chemical modification by emulsion polymerization to achieve good interfacial adhesion between SLF and the pPVC matrix. The SLF with chemical modification were obtained from three different reaction conditions where these SLF have different percentages of grafted and deposited PMMA polymer onto the fiber surface. The incorporation of the SLF into the thermoplastic matrix was carried out using a torque-rheometer and the composites obtained were molded by compression. Tensile and tear mechanical tests were performed on composite samples, and the morphology of the fractured surfaces was analyzed using scanning electron microscopy (SEM). The results show that the incorporation by grafting of polymethyl metacrylate (PMMA) onto the fibers produced a significant improvement of their interfacial adhesion to pPVC, promoting the compatibilization between the fiber surface and matrix. The findings are discussed and interpreted in terms of enhanced adhesion at phase boundaries. Overall, the results confirm that it is possible to produce modified leather composites based on a pPVC matrix, which exhibit relatively high tensile strength, tear resistance and flexibility. These composites are very suitable candidate materials for applications in the footwear industry.

We calculate voltage-matching considerations for stacked independent cells. The calculations show that designs using independent junctions that are voltage matched can achieve better efficiency across temperature, spectrum, and a yearly metric compared to traditional monolithic cells. Voltage matching is shown to be relatively insensitive to temperature and spectrum, but dependent on open circuit voltage as a measure of cell efficiency. Voltage matching can usually yield yearly efficiencies of 98%-99% of the efficiency of a system with each junction operating at its own maximum power point.

Microsystems-enabled photovoltaic (MEPV) technology is a promising approach to lower the cost of solar energy to competitive levels. This paper describes current development efforts to leverage existing silicon integrated circuit (IC) failure analysis (FA) techniques to study MEPV devices. Various FA techniques such as light emission microscopy and laser-based fault localization were used to identify and characterize primary failure modes after fabrication and packaging. The FA results provide crucial information used in provide corrective actions and improve existing MEPV fabrication techniques.

The repair of lexicographic errors occuring during the computer translation of knowledge is performed by approximate string matching algorithms. This article presents a new algorithm that attempts ...

The development of a system for the repair of lexical errors detected in the process of recognizing inorganic chemical names is described. Repairs are based on the calculation of similarity between strings, using the model and approximate matching algorithm detailed in the previous article of this series. A hierarchical data structure is proposed for the storage of information generated during the repair process. This structure comprises two hierarchically-related abstract data types, to permit the storage of partial and total repairs generated by the process. The great amount of information generated by the system might recommend its use in applications requiring explanatory subsystems to report on the success of recognition of user-input information. Problems in the repair process arising from inorganic grammar structures are also examined, and solutions are proposed for cases such as that of the delimiters between significant parts of the inorganic substance name.

This paper proposes a model that permits the development of a tutorial system devoted to teaching formulation and reactions in inorganic chemical. The model is based on both abstract data structures to represent this type of knowledge and the use of an Object-Oriented paradigm which permits the development of complex systems which can be used as a tutorial system for students as well as an expert system for researchers.The user interacts with the system through sentences representing inorganic chemical names (in several nomenclatures) working in a graphic environment that permits the development of powerful user interface necessary in this kind of system.

Two different numerical schemes are proposed for the study of the behavior of a viscous incompressible fluid in a turbulent regime using the M.P.P. model. They differ in their treatment of both velocity and turbulent kinetic energy at the time discretization stage. The first, a Gear scheme, is fully implicit, while the second is of the alternate direction type. In both, the Lagrangian coordinate is calculated by applying an explicit Lax—Wendroff scheme. Various numerical experiments showed good agreement between the two schemes.

Professional Skills, such as the ability to communicate effectively or the ability to gather and integrate information, are not easy to teach or to assess. A traditional exam is not the best way of assessing these skills because it is limited both by time and by the resources students are able to consult. Moreover, in a traditional exam it is difficult to assess if professional skills have been acquired in depth. In this paper we propose to substitute the traditional exam by a take-home exam in which students have more time to solve the questions and are not restricted by the sources they can consult, thereby providing a highly educational task in which students experience a deep learning process. We also analyze what kind of questions should be asked to evaluate professional skills, as well as analyzing the potential drawbacks of these kind of exams (such as inappropriate student behavior). Finally, we show the results of one subject at the Barcelona School of Informatics, in which the take-home exam replaced the traditional exam. This course has been taught over 11 terms with good results.

Xochicalco is an archaeological site located in the state of Morelos in central Mexico. It flourished from 600 to 900 a.d. with numerous multicultural elements. There are several underground rooms carved into the hillside In particular, a room with a shaft that has a hole in the roof whose orientation towards the zenith supports its astronomical purpose. Our hypothesis is that the place was used as a tlayohualchieliztli or camera obscura for astronomical observations. This would be the first evidence of a pre-columbian image forming device. To explore the feasibility of this assertion, the conditions required to produce an image were studied. The aperture diameter in the top of the shaft is far too large to be used as a "pinhole" but it may have been covered with a screen containing a smaller bore-hole. We work out the optimum aperture size. The portion of the sky that could be observed due to the orientation of the shaft was also undertaken. The two most intense celestial objects should produce bright enough images thus suggesting that observation of the sun took place during day-time and observation of the moon during night-time. Amate paper or cloth could have been used to directly draw the position of celestial objects.

A problem was split into subproblems which were then solved in parallel on various computers linked in a network. The resulting solutions were then combined to form the solution to the original problem. Coordinated management of this pooling of solutions required synchronization of machines; this synchronization, together with the prerequisite data transfer (one of the machines must be aware of all the solutions), was achieved through a series of utilities developed using the Remote Procedure Call (RPC) of the NFS.

Thin and small form factor cells have been researched lately by several research groups around the world due to possible lower assembly costs and reduced material consumption with higher efficiencies. Given the popularity of these devices, it is important to have detailed information about the behavior of these devices. Simulation of fabrication processes and device performance reveals some of the advantages and behavior of solar cells that are thin and small. Three main effects were studied: the effect of surface recombination on the optimum thickness, efficiency, and current density, the effect of contact distance on the efficiency for thin cells, and lastly the effect of surface recombination on the grams per Watt-peak. Results show that high efficiency can be obtained in thin devices if they are well-passivated and the distance between contacts is short. Furthermore, the ratio of grams per Watt-peak is greatly reduced as the device is thinned.

GESIM is a system for the storage and retrieval of a great amount of images. The images are stored with TIFF format as part of a database structure. This structure allows the organization and management of a great amount of TIFF images, maintaining the relationship between the different images. The simplicity of the structure and procedures incorporated by GESIM eases its use for the analysis and treatment of images and graphic software allowing integration with textual information databases. The system allows the retrieval of the images using as a selector any of the labels (tags) included in the TIFF format. Additionally, GESIM allows the grouping of related images in independent volumes within the same database. GESIM is a library of functions developed in Microsoft C and also has a user interface that allows the use of its functions through pop-up menus, which makes the procedure easier for non-expert users.

Traditionally, engineering studies have focused on preparing students technically and given little importance to social or ethical aspects, nor the ability to work in multi-disciplinary teams. Currently though, these skills are an added value and have been included in most prestigious centrepsilas curricula. As a result, they have become a subject of study for the education community and the focus of numerous papers. Correspondingly, the Barcelona School of Informatics has developed a hardly explored initiative in order to inculcate these values and help students acquire these skills. This initiative gets them involved in what we call solidarity projects, where both students and professors get administrative and subsidized support to create cooperative work that will provide a solution to specific problems on developing countries and poor local areas. These projects may be introduced in some courses and during Bachelor and Master Thesis and have contributed towards the professional skills development of both students and professors involved.

amebic liver abscess is frequently seen in endemic regions, and has a poor prognosis when diagnosis and treatment are inappropriate.to evaluate and compare our own results; to propose a new classification and therapeutic algorithm.an observational and retrospective study.medical records were reviewed for sex, age, signs and symptoms, images, laboratory tests, size, location, treatment, hospital stay, and morbidity-mortality.sixteen patients with amebic liver abscess had been treated -9 were males, mean age was 30.56 years, all abscesses were solitary, 14 were in the right hepatic lobe, average size was 63.25, and 10 were of the collected type according to N Gbesso s classification. Seven patients had a good response to medical treatment, 6 needed percutaneous drainage, and 3 required surgery. Morbidity was 12.5% and mortality 0%. Average hospital stay was 7.68 days.our results are similar to those in other published series. The addition of two new groups to N Gbesso s classification provides better therapeutic orientation. We believe that early percutaneous drainage for collected abscesses bigger than 5 cm may improve symptoms and shorten hospital stay.

Antecedentes: los abscesos amebianos hepáticos se presentan frecuentemente en zonas endémicas, teniendo mal pronóstico si no son diagnosticados y tratados adecuadamente. Objetivo: evaluar nuestros resultados, ampliar la clasificación ultrasonográfica utilizada y proponer un algoritmo terapéutico. Diseño: retrospectivo observacional. Método: revisión de los expedientes clínicos de los pacientes y valoración de los siguientes datos: sexo, edad, signo-sintomatología, métodos complementarios de imágenes y laboratorio, tamaño, localización, estancia hospitalaria y tratamiento. Resultados: fueron tratados 16 abscesos, 9 fueron hombres, la media etaria fue de 30,56 años, todos fueron únicos, 14 se localizaron en el lóbulo derecho, la media en medida fue de 63,25 milímetros, 10 fueron del tipo coleccionado en la clasificación de N’Gbesso. Siete pacientes tuvieron buena respuesta con el tratamiento médico, en 6 se realizó drenaje percutáneo y en 3 cirugía. La morbilidad fue del 12,5% y la mortalidad del 0%. La estancia hospitalaria global tuvo una media de 7,68 días. Conclusión: nuestros resultados son similares a otras series, el agregado a la clasificación de N’Gbesso de abscesos intermedios y complicados o con signos de alarma mejora la orientación terapéutica, creemos que el drenaje precoz en abscesos coleccionados de 5 o más cm mejora la sintomatología y disminuye la estancia hospitalaria.

Among their educational objectives, Computer Science courses do not usually aim at developing skills such as the gathering of information, oral and written communication, or teamwork; nor do they seek to heighten students' awareness in terms of solidarity, the environment, justice or progress. In the subject "PC Architecture" at the Facultat d'informatica de Barcelona (Spain), the aforementioned items are indeed included in the educational objectives, but without any additional effort to the student. The teaching strategies include the following: (i) students are organized into groups, which prepare a project on a topic related to the objectives of the course, (ii) students are required to make a public presentation of their project and answer questions from their colleagues, and (iii) the lab work is done in collaboration with an NGO. It consists of repairing PCs provided by donars. Once repaired, PCs are destined for projects in solidarity with developing countries. Over the last two years, we have evaluated four courses by means of student surveys, whose results have been very positive. As instructors, we have observed a remarkable improvement in the quality of the presentations throughout the course. Furthermore, some students continue their collaboration with the NGO beyond the end of the course.

To know in a quantitative manner the degree of discomfort and pain of the biopsies of the prostate and to evaluate the effectiveness of the transrectal lidocaine.We performed 140 transrectal biopsies of the prostate, Patients were included on a random basis into two arms: one of them received intrarectal lidocaine, 20 mg (group 1, n = 71) and the other group received placebo (group 2, n = 28) both of them ten minutes prior the proceeding.The global pain mean was 3.7 (0 no pain, 10 highest pain) and the global discomfort mean was 3.5. The group 1 patients showed a trend to feel less pain and discomfort although it did not reach the necessary statistic significance (p = 0.7 y p = 0.5 respectively).We do not achieve the good results obtained by other groups in order to decrease the degree of pain and discomfort with the use of intrarectal lidocaine. We did not find relationship between the PSA level, previous biopsies, intrarectal lidocaina and degree of information received and the degree of pain and discomfort.

The objective of this study is to assess the contribution of job strain, according to the Karasek's demand-control model, on the job satisfaction and stress-related psychological symptoms in nurses and nurse aids of caring units of a public hospital of Barcelona, independently of other aspects of both the work and the outside of work environment.A cross-sectional study was designed and data were collected through a self-administered questionnaire that was answered by 273 people of caring units of a public hospital of Barcelona (response rate 81%). Job strain that classifies workers into four groups, low strain, high strain, active jobs, and passive jobs, was measured through the items of the "Job Content" questionnaire about demands and control adapted for this study. Job satisfaction and two types of psychological symptoms, anxious and somatic symptoms were analyzed first at the bivariate level and then by adjusting logistic regression models that included both work and nonwork variables.The three outcomes were significantly associated with job strain, being the low strain situation the most positive one and the high strain the most negative one. Adjusted odds ratios (OR) of the high strain jobs versus the low strain jobs were 0.20 (CI 95% = 0.05-0.45) for job satisfaction, 3.45 (CI 95% = 1.63-7.33) for anxious symptoms and 3.72 (CI 95% = 1.65-8.38) for the psychosomatic symptoms. Passive and active jobs fell in between these extremes. Other variables both from the work environment and from the outside of work environment were associated with these outcomes.This study shows the importance of job strain on the job satisfaction and stress-related psychological symptoms of this group of workers, even after adjusting by other variables of the work and of the outside of work environment. This finding underscores the importance of considering, jointly with the classical work hazards, those related with the psychosocial work environment in implementing strategies for improving health and welfare among nurses.

Aknowledge acquisition system is proposed to develop of inorganic chemical expert systems. The acquisition system is compose by a series of subsystems devoted specific tasks. A subsystem named Formulator carried out the acquisition of semantic knowledge through nomenclature of inorganic substance and to build a abstract data structure, named DIMS (Dynamic Internal representation of Molecular Structure), which represent all kind of knowledge corresponding inorganic substance. Others subsystem (Painter, Calculator, Nomenclator, Reactor, etc.) operates with this structure to obtain a new knowledge (physical-chemical properties, topological properties, reactions characteristic, etc.) to permits the develop of expert system in chemical inorganic area.

The modification to the DeFord and Hume method for differential pulse polarography is applicable to quasi-reversible and irreversible processes and takes into account any change in the reversibility of the system when the concentration of the ligand is altered. Three computer programs for the calculation of the stability constants are outlined: two of them are based in the weighted least-squares and the third is a simulation process.

Le calcul de certaines proprietes a l'equilibre, de systemes electrolytiques, necessite la connaissance des coefficients d'activite en phase liquide des constituants de ces systemes. L'estimation du coefficient d'activite ionique moyen de l'electrolyte permet, pour des systemes binaires, de calculer ces coefficients d'activite. Dans cette revue bibliographique sont presentees les principales expressions analytiques, de coefficients d'activite ioniques moyens, fournies par la litterature. II est possible de classer ces expressions en plusieurs grandes categories en fonction des modeles dont elles derivent. Des criteres de choix, de l'une ou l'autre de ces equations, sont proposes suivant le type de systeme electrolytique et le domaine de concentration etudies.