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BACKGROUND: This research was focused on measuring the TFP bioeconomy post-Covid-19 in six regions of the world. METHODS: The panel data was organized with FAO Statistics data. Linear programming with an enveloping data analysis (DEA) approach was used to measure the Malmquist TFP indices to determine the inter-annual productivity and technical efficiency changes by region. RESULTS: The results show that the effect of Covid-19 on the bioeconomy productivity during the period 2012-2021 on average decreased by 11.6%. This effect was explained by the decomposition of the productivity change into the changes in technical efficiency. The workers decreased their efficiency by 11.7%. In the Northern American region, it decreased by 21.6%, in the Southern European region by 10.1, and in Western Europe by 11.7%. CONCLUSION: The results show a downward trend that was affected in the year 2019 by Covid-19, however, it was possible to recover in the following year. One of the conclusions of these results is the effect of the immediate strategies that the governments of the region implemented. This effect was a little slower in the North American, Southeastern, and Eastern European regions. Finally, it is concluded that the measures implemented by the governments in the studied regions had an increasing effect in conditions of variable scale returns. In other words, the companies that remained on a constant scale decreased.

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Background: This paper aims to examine the efficiency of Mexico's dairy farms within its four regions of Tlaxcala Stated. Methods: The Envelopment Data Analysis (DEA) applied to the variable returns to a scale model (VRS) for the year 2020. Also, Examine the statistical accuracy of efficiency estimation using bootstrap resampling techniques. The results reveal that Tlaxcala's dairy farm efficiency, on the other hand, was adversely influenced by three inputs (costs): cost of investment in livestock, the total annual cost for feeding, reproduction, diseases and treatments, preventive medicine, sanitation, milking, fuel, and total labor. Results: The efficiency distribution among farms using VRS, CRS, and FDH technologies reveals varying patterns. Under VRS and CRS, the majority of farms exhibit high efficiency within the 0 to less than 0.2 range, while FDH displays a broader distribution, with notable efficiency at 1 and across various ranges. These findings highlight the diverse landscape of efficiency levels across different technological approaches within the agricultural sector, offering valuable insights for optimization strategies and resource allocation. Conclusions: The utilization of Bootstrap methodology enhances the reliability of efficiency assessments by providing robust statistical techniques that accommodate non-normal data distributions. By incorporating Bootstrap, decision-makers can obtain more accurate estimates of efficiency levels and confidence intervals, thereby making informed decisions regarding resource allocation and optimization strategies within the agricultural sector. As part of the study, provided The Policy suggestions.

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Background: The research focused on evaluating the biological and reproductive parameters of the species Spodoptera sunia with the introduction of field genetic material, in the Noctuid Insect Breeding Laboratory. Methods: The experiment consisted of three treatments and three repetitions involving 30 individuals each. Field-collected S. sunia population was reared in the laboratory under semi-controlled conditions of temperature and humidity for three generations. The progeny of the third generation was crossed with the laboratory population and the resulting progeny was observed for growth and reproductive fitness. Results: The results revealed that the hybrid progeny (T3) has a sex ratio (F: M) of 0.82, as against 1.22 and 0.76 observed in the field (T1) and lab populations (T2) respectively. The T1 females oviposited 196 egg masses as against 160 and 59 egg masses by T3 and T2 females respectively. The larval growth was more in hybrid progeny with shorter larval duration. However, no variation was observed in the incubation and pupal periods. Conclusions: Since the most optimal results were obtained in T2 and T3, it is recommended to introduce genetic material every six months to maintain a good laboratory population of the insect host under study and better breeding of its natural enemies.

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Background: This study focused on evaluating the diversity and richness of the edaphic macrofauna in eight banana farms in the western zone of Nicaragua. Methods: The sampling design was random and descriptive, it was divided into two phases, the first was the collection of the sample, and the second was the classification, coding, and storage of the extracted macrofauna populations. The sampling method employed included the extraction of soil and litter samples. Soil samples were collected using a wooden frame (monolith), with each sample weighing approximately 1 kilogram and taken from a depth of 0.20 cm. Litter samples were collected from the soil surface. A total of 80 samples were collected, with 40 soil samples and 50 litter samples obtained across the 8 plantain farms. Results: The results showed that the relative abundance of biodiversity was higher in the 0-20 cm soil depth stratum than in the branch and leaf biomass strata. The values of the diversity indices of Simpson's Dominance, Shanon, Margalef, and Equity were in the normal range, with a tendency towards low diversity. Likewise, in the richness of species, the Dominance or most abundant genus were earthworms (Oligochaeta) and Hymenoptera ( Solenopsis, Leptothorax, Camponotus, Pheidole), indicating the directly proportional relationship, that is to say, that the greater the number of earthworms the production increases and the greater the number of Hymenoptera it decreases, confirmed with the Pearson correlation coefficient with a reliability of 95%. Conclusions: It was concluded that based on the estimates of the diversity indicators, two detritivore genus (earthworms and Hymenoptera) were the ones with the more dominance, being important in the production of the banana agrosystem due to the decomposition of organic matter and its nutritional contribution to the plant. We observed a direct correlation with earthworms and an indirect relationship with Hymenoptera.

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Background: This work was focused on measuring environmental inefficiency in Mexican dairy farms, considering climate change variables related to the emission of greenhouse gases (GHG) and planetary geomagnetic activity. Methods: The applied methodology measures the eco-efficiency of Mexican dairy farms using the empirical application of a stochastic frontier model of the bioeconomy. The productive sector of the bioeconomy studied was the eco-intensification of the livestock production system (dairies). The environmental inefficiency effect was assumed to be a distribution-independent truncation of a normal distribution with constant variance, while the mean was a linear environmental function of the observable variable. Results: The results showed that the coefficients of the frontier model were highly significant, highlighting the investment in livestock (50%). The inefficiency model had an impact on climate variation with greenhouse gas emissions CH4 (1.96%). The results of the environmental technical efficiency in geometric average were 81.28%. The producers that reached the border with a technical efficiency equal to 1 are the references for the rest, marking the relative technical efficiency. Conclusions: It was concluded that the coefficients in the model were very significant, showing the level of investment in livestock (50%). The low-performance model estimates the impact of climate change on GHG emissions CH4 (1.96%) explaining the trend of increasing GHG emissions, keeping in view that the management of food and cattle during the study period were affected by summer feeding, which allowed considering the activity of GHG emissions. According to the results, the geometric mean environmental performance of engineering is 81.28%.

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Hyaluronic acid (HA) and gelatin (Gel) are major components of the extracellular matrix of different tissues, and thus are largely appealing for the construction of hybrid hydrogels to combine the favorable characteristics of each biopolymer, such as the gel adhesiveness of Gel and the better mechanical strength of HA, respectively. However, despite previous studies conducted so far, the relationship between composition and scaffold structure and physico-chemical properties has not been completely and systematically established. In this work, pure and hybrid hydrogels of methacroyl-modified HA (HAMA) and Gel (GelMA) were prepared by UV photopolymerization and an extensive characterization was done to elucidate such correlations. Methacrylation degrees of ca. 40% and 11% for GelMA and HAMA, respectively, were obtained, which allows to improve the hydrogels' mechanical properties. Hybrid GelMA/HAMA hydrogels were stiffer, with elastic modulus up to ca. 30 kPa, and porous (up to 91%) compared with pure GelMA ones at similar GelMA concentrations thanks to the interaction between HAMA and GelMA chains in the polymeric matrix. The progressive presence of HAMA gave rise to scaffolds with more disorganized, stiffer, and less porous structures owing to the net increase of mass in the hydrogel compositions. HAMA also made hybrid hydrogels more swellable and resistant to collagenase biodegradation. Hence, the suitable choice of polymeric composition allows to regulate the hydrogels´ physical properties to look for the most optimal characteristics required for the intended tissue engineering application.

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Determination of the main nutritional requirements at different developmental stages is a prerequisite in the formulation of feeds for newly cultured fish species. In the present study, the lipid and protein requirements of larvae of a native Mexican fish, the three-spot cichlid Cichlasoma trimaculatum, were assessed using a two-factor experimental design that considered four protein (35, 40, 45, and 50%) and two lipid levels (16 and 22%) on growth, survival, and digestive enzyme activities. The best growth and feed efficiency results were obtained when larvae were fed diets including 45% protein and 22% lipids. Comprehensive evaluation of the profile of digestive enzymes using multivariate analysis also demonstrated significant differences in nutritional condition generated by varying inclusion of nutrients. Thus, an increase in protein led to an increase in alkaline protease activity and a reduction in leucine aminopeptidase activity, and the reduction of dietary lipid content led to a significant increase in lipase and trypsin enzymatic activities. Based on our results, C. trimaculatum larvae have a high capacity to hydrolyze both nutrients (protein and lipids) for the high digestive enzyme activities and increase their growth, particularly with a diet containing 45% protein and 22% lipids.

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The use of radioactive emanations has been of great importance for the performance of endourology procedures, such as percutaneous nephrolithotomy (NLP). The damage to health caused by radiation has been a sensitive issue. The objective of this work was to determine the dose received by the surgeon during NLP and the total dose generated by the fluoroscope. A cross-sectional study was conducted with data from a cohort study with a duration of 18 months that included 101 patients. Radiation was measured with dosimeter during the last 6 months. During the last 6 months of the study, 34 patients were submitted to surgery. The average age was 47 years. Average fluoroscopy time was 58.3 second (24-122 seconds) in both male and female groups, with 57.16 seconds and 58.95 seconds per case, respectively (P = .6). Radiation emitted during 6 months for the 34 patients was 330.5 mGy. The total radiation measured by the dosimeter was 1 mSv, which is equivalent to 0.3% of the total radiation applied during the procedures. Doses measured by the dosimeter on the surgeon were within the recommended annual doses although dose received by the hands exceeds the authorized limits (500 mSv/y).

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INTRODUCTION: In Mexico, the first meniscus transplant was performed in 2002. The objective was to describe the clinical evolution of patients with pain associated with postmenisectomy syndrome, who underwent meniscal allograft transplantation (MAT), with bony blocks via arthroscopy, with follow-up to one year. MATERIAL AND METHODS: A retrospective cohort study with a one-year follow-up was conducted. We included patients with joint interlining pain secondary to partial or total menisectomy, between 15 and 55 years of age, of both sexes, who underwent MAT. The clinical evolution was evaluated with visual analogue scale (VAS), SF-36 and Lysholm scale; the results are described in frequencies, percentages and p value was significant at 0.05. RESULTS: We included nine patients; eight men and one woman with an age of 31.3 years (16-52), the follow-up was 16.6 months (12-23). The preoperative VAS was 8.5 (6-10) and, at one year of follow-up, the average of this scale was 1.25 (0-5) (p 0.001). In the follow-up one year after the MAT, the Lysholm scale was on average 91 (68-100) and the SF-36 was on average 79.17 (65-92.92); three patients returned to their sports practice prior to the injury. CONCLUSION: This is the first report in Mexico that describes the one year follow-up of the MAT; significant clinical improvement was demonstrated (p 0.001) with remission of pain in the knee with previous menisectomy and in some cases the return to sports practice.

INTRODUCCIÓN: En México se realizó el primer trasplante de menisco en 2002. El objetivo fue describir la evolución clínica de pacientes con dolor asociado al síndrome postmeniscectomía que fueron sometidos a trasplante de menisco alogénico (MAT), con bloques óseos vía artroscópica con seguimiento a un año. MATERIAL Y MÉTODOS: Se realizó un estudio de cohorte retrospectiva con seguimiento a un año; se incluyeron pacientes con dolor en interlínea articular secundario a meniscectomía parcial o total, entre 15 y 55 años de edad, de ambos sexos, que fueron sometidos a MAT. La evolución clínica se evaluó con EVA, SF-36 y escala de Lysholm; los resultados se describen en frecuencias, porcentajes y valor de p significativa 0.05. RESULTADOS: Se incluyeron nueve pacientes; ocho hombres y una mujer con edad de 31.3 años (16-52), el seguimiento fue de 16.6 meses (12-23). La EVA prequirúrgica fue de 8.5 (6-10) y al año de seguimiento el promedio de esta escala fue de 1.25 (0-5) (p 0.001). En el seguimiento a un año posterior al MAT, la escala de Lysholm fue en promedio de 91 (68-100) y la SF-36 fue en promedio de 79.17 (65-92.92); tres pacientes regresaron a su práctica deportiva previa a la lesión. CONCLUSIÓN: Éste es el primer reporte en México del seguimiento a un año del MAT; se demostró mejoría clínica significativa (p 0.001) con remisión del dolor en la rodilla con meniscectomía previa y en algunos casos el retorno a la práctica deportiva.

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BACKGROUND: With the availability of high-quality asthma guidelines worldwide, one possible approach of developing a valid guideline, without re-working the evidence, already analysed by major guidelines, is the ADAPTE approach, as was used for the development of National Guidelines on asthma. METHODS: The guidelines development group (GDG) covered a broad range of experts from medical specialities, primary care physicians and methodologists. The core group of the GDG searched the literature for asthma guidelines 2005 onward, and analysed the 11 best guidelines with AGREE-II to select three mother guidelines. Key clinical questions were formulated covering each step of the asthma management. RESULTS: The selected mother guidelines are British Thoracic Society (BTS), GINA and GEMA 2015. Responses to the questions were formulated according to the evidence in the mother guidelines. Recommendations or suggestions were made for asthma treatment in Mexico by the core group, and adjusted during several rounds of a Delphi process, taking into account: 1. Evidence; 2. Safety; 3. Cost; 4. Patient preference - all these set against the background of the local reality. Here the detailed analysis of the evidence present in BTS/GINA/GEMA sections on prevention and diagnosis in paediatric asthma are presented for three age-groups: children with asthma ≤5 years, 6-11 years and ≥12 years. CONCLUSIONS: For the prevention and diagnosis sections, applying the AGREE-II method is useful to develop a scientifically-sustained document, adjusted to the local reality per country, as is the Mexican Guideline on Asthma.

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Resumen El presente artículo es una amplia revisión bibliográfica de algunos de los polímeros naturales más utilizados en la fabricación de apósitos para curación de heridas cutáneas y regeneración de piel en los últimos años. Asimismo, se presenta un análisis descriptivo de los polímeros de origen natural más estudiados en la ingeniería de tejidos, remarcando sus propiedades físicas, químicas y biológicas. Encontrando que las investigaciones más recientes se han centrado en la exploración de apósitos a partir de biopolímeros como una alternativa a los materiales sintéticos derivados del petróleo, debido a las propiedades que poseen, como una mayor biodegradabilidad, biocompatibilidad y sostenibilidad por ser obtenidos naturalmente. Sin embargo, aún no existe un apósito ideal que pueda ser aplicado de manera eficiente en todos los tipos de heridas; por lo que los investigadores se han enfocado en el desarrollo y la optimización de apósitos que satisfagan la mayoría de las necesidades para una etapa en particular de la herida.

Abstract This review includes the bio-polymers most used in recent years for the manufacturing of materials used as dressings in cutaneous wound healing and skin regeneration. Also, the natural polymers most studied in tissue engineering are mentioned, highlighting their physical, chemical and biological properties for skin regeneration and wound healing. Through an extensive review of the clinical and research uses different types of natural polymers were compared, as well as the results of chemical and biological tests carried out during experimental research performed internationally.

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Aquaculture in Mexico has been developed by the cultivation of commercial species. In Tabasco, the cultivation of native species is mainly limited by the lack of nutrition studies to support its crop profitability. Among these species is the tropical gar (Atractosteus tropicus), which has great potential for cultivation. However, the nutritional value of carbohydrates in diets for this species which contribute to improved growth and survival, have not been evalulated,. Thus, in the present investigation, isoprotein and isolipid diets have been designed based on the substitution of cellulose by corn starch (D1: 0% starch-15% cellulose, D2: 7.5% starch-7.5% cellulose and D3: 15% starch-0% cellulose) and compared with a commercial trout diet (45% protein and 16% lipids). A total of 1800 larvae (0.008 ± 0.002 g and 10.5 ± LT 0.126 mm) were used, distributed in a recirculation system in order to evaluate growth and survival for 30 days. The results show higher growth and survival of 97% of larvae fed the D3 diet, while cannibalism in the species was mitigated. Major digestive enzyme activities occurred (acid protease, alkaline protease, trypsin, chymotrypsin, leucine aminopeptidase, carboxypeptidase A, lipase, α-glucosidase and amylase) for larvae fed D3. It is concluded that the contribution of corn starch (15%) replacing cellulose in the diet improves growth and survival of this species.

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Changes in digestive enzyme activity and histology were studied in Atractosteus tropicus embryos, larvae and juvenile periods. Alkaline protease, chymotrypsin, carboxypeptidase A, lipase and α-amylase were detected in all periods and gradually increased until reaching the maximum peak in juveniles; meanwhile, acid protease was first detected at 5 days after hatching (dah) when first feeding started and trypsin and leucine aminopeptidase activities were detected from 19 dah, their values being increased gradually until reaching a maximum value at 31 dah. Acid and alkaline phosphatase activities increased from yolk-sac absorption (3 dah) until day 31 after hatching. Zymogram for acid protease showed two bands in active forms (0.4 and 0.5 Rfs) from day 5 after hatching and a third protease form (0.3 Rf) that appears at 31 dah. Two active forms (26.3 and 24.9 kDa) were detected using SDS-PAGE alkaline proteases zymogram at 5 dah, and an additional active form (44.1 kDa) was detected at 7 dah. Regarding the histological development of the digestive system, the exocrine pancreas containing zymogen granules was already visible at 3 dah, whereas at 5 dah first gastric glands were already detected in the stomach. Between 7 and 9 dah, the digestive tract of A. tropicus resembled that of a juvenile specimen with a well-developed and short oesophagus, stomach divided into a glandular and non-glandular (pyloric) stomach, folded intestine with pyloric caeca and a well-developed spiral valve (posterior intestine). Considering this, larvae of A. tropicus are capable of digesting several foods from yolk absorption (3 dah), maximizing its activities at 15 dah, age at which the organisms maximize its capability to absorb nutrients from diets provided.

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A study was performed in order to understand the development of digestive enzymes during initial ontogeny of Cichlasoma trimaculatum, for which the activity of acidic and alkaline proteases, lipases, amylases and phosphatases was determined by means of biochemical and electrophoretic analysis. Our results showed that the activity of alkaline proteases, trypsin and chymotrypsin is present from day 6 after hatching (dah) during exogenous feeding with Artemia nauplii. The activities of carboxypeptidase A and leucine aminopeptidase are present from the first days, increasing at 6 dah and reaching their maximum activity at 9 dah while acid protease activity started at 9 dah. Furthermore, the lipase activity is detected on 6 dah and keeps increasing and decreasing on 17 dah. Amylase activity is detected on 3 dah, presenting fluctuations until 45 dah, where it reaches its maximum activity. Acid and alkaline phosphatases are detected from 3 dah and reach a maximum activity between 13 and 19 dah. The SDS-PAGE electrophoresis revealed six types of bands in the alkaline proteases, with molecular weight between 113.4 and 20.4 kDa. First three bands appear on 6 dah, but it is until 11 dah when all isoforms appear. Based on these results, it is considered that this species completes its digestive enzymatic machinery from day 9 after hatching, therefore is recommended to perform the transition from live feed to inert feed at 15 dah.

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El objetivo de esta investigación fue evaluar el efecto de la inclusión de diferentes niveles de biomasa de levaduras, producidos al fermentar hidrolizados de residuos de la industria bananera, sobre los parámetros zootécnicos de pollos de engorde, evaluando además el impacto económico de su uso en las dietas. Se utilizaron 210 pollos de engorde de un día de edad, distribuidos completamente al azar en cinco tratamientos, en una relación de seis réplicas por tratamiento y siete pollos por réplica. El periodo experimental comprendió 42 días; el alimento y el agua se dispensaron a voluntad. Las dietas experimentales fueron: T1- Control negativo sin levadura, T2- Control positivo con levadura comercial a razón de 1,5 kg ton-1 de alimento, T3- Levadura experimental a razón de 0,5 kg ton-1 de la dieta, T4- Levadura experimental a razón de 1,0 kg ton-1 de la dieta y T5- Levadura experimental a razón de 1,5 kg ton-1 de la dieta. Se observó mayor consumo de acumulado alimento en el tratamiento 4 (1kg ton-1 de levadura) con respecto a los demás tratamientos evaluados. No hubo diferencias significativas (P>0.05) en las otras variables evaluadas en el estudio. Se constató beneficio económico con el uso del tratamiento 4 pues se obtuvieron mejores retornos (precio de venta del pollo - costo de la alimentación) que fueron mayores a los observados en los tratamientos 1, 2, 3 y 5 en 153, 82, 62 y 161 pesos($) ave-1, respectivamente.

The objective of this study was to evaluate both the effect of including different levels of yeast biomass produced during the fermentation of banana waste residues on broiler productivity and the economic return of the exercise. We used 210 one-day-old broilers, which were distributed at random into five treatments, with six replicates per treatment and seven chicks per replicate, housed in vertical batteries equipped with electric heating. Feed and water were provided ad libitum. The experimental period lasted 42 days and the experimental diets were: T1- Negative control without yeast, T2- Positive control with commercial yeast at 1.5 kg ton-1 of feed, T3- experimental yeast at 0.5 kg ton-1 of diet, T4- experimental yeast at 1.0 kg ton-1 of diet and T4- experimental yeast at 1.5 kg ton-1 of the diet. Both animal productivity and economical return were evaluated. Significant differences (P>0.05) were present in the cumulative feed intake in treatment 4 (1kg ton-1 yeast) with respect to the other treatments. No significant differences were found in the other variables assessed in the study. There was an economic benefit to including treatment 4, in the form of higher returns (chicken sale price minus feed costs) of 153, 82, 62 and 161 Colombian pesos ($) bird-1, compared to those observed in treatments 1, 2, 3 and 5, respectively.

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Como parte de un proyecto de desarrollo de un modelo de gestión tecnológica para sistemas de producción de ovinos y caprinos en Colombia, utilizando un abordaje interpretativo y mediante la realización de un estudio de caso múltiple descriptivo, se evaluaron conductas, actitudes, percepciones y experiencias de productores de ovejas y cabras asociadas con la producción y utilización de la información, como base para la formulación de un modelo conceptual de la gestión de la información ajustado a las diversas necesidades y características socio-económicas, tecnológicas y culturales de estos sistemas de producción animal. Utilizando la Metodología de Sistemas Blandos (MSB), se identificaron los elementos que describen el ámbito y los límites del Sistema de Gestión de la Información (SGI) en los sistemas de producción animal citados. Se encontró que el productor es el cliente, actor y propietario principal del SGI y que, por lo tanto, el modelamiento conceptual de dicho sistema debe tener en cuenta las características individuales de los productores, tales como su personalidad, experiencia, edad, educación y visión de su negocio, entre otras, las cuales determinan la forma como éstos manejan la información y toman decisiones. Se identificó que el manejo de la información solamente cubre los aspectos operativos y transaccionales, sin alcanzar los niveles administrativos y estratégicos. El ejercicio ha demostrado que la MSB constituye una herramienta flexible y eficaz en el diseño de sistemas de gestión de la información al tener en cuenta las visiones y perspectivas de los usuarios.

As a part of a project to develop a technological management system for Colombian sheep and goat production systems, using an interpretive approach by means of a descriptive multiple case study, we assessed behaviors, attitudes, perceptions and experiences of sheep and goat producers associated with their patterns of information management to propose a conceptual model of the Information Management System (IMS) that suits the diverse socio-economic, technological and cultural features of these type of producers. Using the Soft System Methodology (SSM), the elements that describes the scope and boundaries of the system were identified and depicted. The producer is described as the main customer, actor and owner of the IMS, so the conceptual model to be developed needs to account their diverse personal characteristics, like character, experience, age, education level, and business visions, among others, which influence the way how the producers manage the information and take decisions. It was also identified how the information management only covers operational transactions and fairly reach the administrative or strategic level. The exercise has shown the flexibility and efficacy of the SSM in the design of information management systems bringing in account the users visions and perspectives.

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Tropical gar (Atractosteus tropicus) is an economically and socially important freshwater species from Southeastern Mexico, with a high aquaculture potential. With this in mind, the purpose of this study was to characterize the digestive proteases of tropical gar juveniles through biochemical and electrophoretic analyses. Twenty specimens with an average weight of 73.6 ± 12.7 g were used to obtain stomach and intestinal tissue from which multienzymatic extracts were prepared. The general activities of the acid and alkaline proteases were evaluated, as well as the specific activities of trypsin, chymotrypsin, leucine aminopeptidase and carboxypeptidase A. The effect of the pH and temperature on the proteases was also analyzed, together with the composition of the multienzymatic extracts using protease inhibitors and electrophoretic tests. Results showed that A. tropicus have a functional stomach in which protein hydrolysis starts with pepsin and which contains endo- and exopeptidases (trypsin, chymotrypsin, leucine aminopeptidase and carboxypeptidase A) and proteases that are resistant to high temperatures (45 and 55 °C for alkaline and acid proteases, respectively) and pH values. Using zymogram technique, we found two acid protease isoforms (0.35 and 0.71 rf) and five alkaline protease isoforms (83.7, 43.7, 27.5, 24.0 and 19.4 kDa), which decrease or disappear with the different inhibitors. Thus, this species is considered to be a carnivore capable of adapting to its environment by consuming different types of proteins from preys and also could adapt rapidly to consume a compound diet with different animal protein sources.

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AIM: The relevance of the cytidine diphosphate-choline and Rho GTPases pathways in the pathogenesis of cancer has been previously demonstrated. We investigate by a case-control association study if genetics variants in these pathways are associated with risk of developing lung cancer. METHODS: Thirty-seven tag SNPs were evaluated as risk factor of NSCLC in 897 cases and 904 controls. RESULTS: Six SNPs were nominally associated with lung cancer risk, which were not significant after the Bonferroni correction for multiple comparisons. No association was observed with the remaining 31 analyzed SNPs, neither it was found significant in haplotype frequencies. CONCLUSIONS: Although the implication of the two pathways investigated in our study in carcinogenesis is well established, our null results suggest that common genetic variants in CDP-choline and Rho GTPases-related genes are not risk factors for lung cancer.

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El objetivo de este estudio fue investigar la relación del conducto dentario inferior (CDI) con estructuras anatómicas adyacentes al tercer molar, tales como: cresta ósea mandibular (COM), cortical ósea lingual y vestibular mandibular (COLM y COVM) respectivamente, borde basilar mandibular (BBM) y el tercer molar según sexo y grupo etario en ambos lados. Se analizó una muestra no probabilística accidental de 217 sujetos sometidos a tomografía Cone-Beam (113 mujeres y 104 hombres) entre 15 y 34 años, realizado entre los años 2010-2013 en el Instituto Unimagen Craneo Facial Valencia del Centro Médico Dr. Rafael Guerra Méndez; se efectuaron imágenes volumétricas utilizando un equipo y sistema operativo Iluma® 2.0.6; se enumeraron las variables anatómicas y se realizó un análisis cuantitativo realizando mediciones que relacionan la distancia entre el conducto y las variables anatómicas antes mencionadas. Relación CDI-COM: hemiarcada derecha 17±2,5 mm, hemiarcada izquierda 17,2±2,7; CDI-COVM: hemiarcada derecha 5,4±1,7 mm, hemiarcada izquierda 5,3±1,8; CDI-COLM: hemiarcada derecha 2,9±1,1 mm, hemiarcada izquierda 2,9±1,1 mm; CDI-BBM: hemiarcada derecha 9,9±2,8 mm, hemiarcada izquierda 9,9±2,7 mm, CDI-tercer molar inferior: 2,1±2,1 mm, hemiarcada izquierda 2,1±2,4 mm. En el análisis descriptivo no se evidenciaron diferencias en cuanto a sexo, grupo etario y hemiarcada en la población de estudio. El sistema Cone-Beam es fundamental para evaluar la relación del conducto dentario inferior y las estructuras anatómicas antes comentadas.

The objective of this study was to investigate the relationship of the inferior dental canal (CDI) with anatomical structures adjacent to the third molar, such as mandibular bone crest (COM), lingual and vestibular cortical bone (COLand VOC) respectively, basilar border (BBM) and the third molar according to sex and age in both sides. We analyzed a no probabilistic accidental sample in 217 subjects undergoing tomography Cone-Beam (104 men and 113 women) between 15 and 34 years, between 2010-2013 at Unimagen craniofacial Valencia Institute, Centro Medico Dr.Rafael Guerra Méndez, we did volumetric images using a computer and operating system Iluma 2.0.6; anatomical variables listed and a quantitative analysis was performed by making quantitative measurements performing the distance between the duct and the aforesaid anatomical variables. CDI-COM relationship: right hemiarcade 17±2, 5 mm, left hemiarcade, 17,2±2, 7; CDI-COVM: right hemiarcade 5, 4±1, 7 mm, left hemiarcade 5, 3±1, 8; CDI-COLM: right hemiarcade 2,9± 1 mm, left hemiarcade 2, 9±1 mm; CDI-BBM: right hemiarcada 9, 9±2, 8 mm, left hemiarcade 9, 9±2, 7 mm, CDI-third inferior molar: 2, 1±2, 1 mm, 2 left hemiarcade, 1±2, 4 mm. At the descriptive analysis didn't show differences in terms of sex, age and hemiarcadein population study group. The system cone-beam is essential to evaluate the relationship of the inferior dental canal and before commented anatomical structures.

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Common snook (Centropomus undecimalis) is one of the most important marine species under commercial exploitation in the Gulf of Mexico; for this reason, interest in developing its culture is a priority. However, larviculture remains as the main bottleneck for massive production. In this sense, our objective was to determine the changes of digestive enzymes activities using biochemical and electrophoretic techniques during 36 days of Common snook larviculture fed with live preys (microalgae, rotifers, and Artemia). During larviculture, all digestive enzymatic activities were detected with low values since yolk absorption, 2 days after hatching (dah) onwards. However, the maximum values for alkaline protease (6,500 U mg protein(-1)), trypsin (0.053 mU × 10(-3) mg protein(-1)), and Leucine aminopeptidase (1.4 × 10(-3) mU mg protein(-1)) were detected at 12 dah; for chymotrypsin at 25 dah (3.8 × 10(-3) mU mg protein(-1)), for carboxypeptidase A (280 mU mg protein(-1)) and lipase at 36 dah (480 U mg protein(-1)), for α-amylase at 7 dah (1.5 U mg protein(-1)), for acid phosphatases at 34 dah (5.5 U mg protein(-1)), and finally for alkaline phosphatase at 25 dah (70 U mg protein(-1)). The alkaline protease zymogram showed two active bands, the first (26.3 kDa) at 25 dah onwards, and the second (51.6 kDa) at 36 dah. The acid protease zymogram showed two bands (RF = 0.32 and 0.51, respectively) at 34 dah. The digestive enzymatic ontogeny of C. undecimalis is very similar to other strictly marine carnivorous fish, and we suggest that weaning process should be started at 34 dah.

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