Diagnosis for ecological intensification of maize-based smallholder farming systems in the Costa Chica, Mexico

Enhanced utilization of ecological processes for food and feed production as part of the notion of ecological intensification starts from location-specific knowledge of production constraints. A diagnostic systems approach which combined social-economic and production ecological methods at farm and field level was developed and applied to diagnose extent and causes of the perceived low productivity of maize-based smallholder systems in two communities of the Costa Chica in South West Mexico. Social-economic and production ecological surveys were applied and complemented with model-based calculations. The results demonstrated that current nutrient management of crops has promoted nutrition imbalances, resulting in K- and, less surprisingly N-limited production conditions, reflected in low yields of the major crops maize and roselle and low resource use efficiencies. Production on moderate to steep slopes was estimated to result in considerable losses of soil and organic matter. Poor crop production, lack of specific animal fodder production systems and strong dependence on animal grazing within communal areas limited recycling of nutrients through manure. In combination with low prices for the roselle cash crop, farmers are caught in a vicious cycle of cash shortage and resource decline. The production ecological findings complemented farmers opinions by providing more insight in background and extent of livelihood constraints. Changing fertilizer subsidies and rethinking animal fodder production as well as use of communal lands requires targeting both formal and informal governance structures. The methodology has broader applicability in smallholder systems in view of its low demand on capital intensive resource

Impact of concurrent pregnancy and lactation on maternal nestbuilding, estradiol and progesterone concentrations in rabbits

[EN] We evaluated the impact of concurrent pregnancy and lactation on: nest-building (i.e., digging, straw-carrying, hair-pulling), food intake, milk output, body weight, and the concentration of estradiol and progesterone in blood. Digging was lower in pregnant-lactating (PL) rabbits, compared with pregnant-only (PO) does, on 21-23 d (52±64 vs. 104±86 g, respectively; mean±SD; P<0.05). Straw-carrying was also reduced in PL does on 24-26 d (9±27 vs. 79±94 g; P<0.005), 27-29 (27±56 vs. 99±77 g; P<0.005), and in the total amount of material introduced into the nest box (132±167 vs. 286±217 g; P<0.02). Hair-pulling was expressed by practically all animals. Food intake declined in PO does on the three days preceding parturition (P<0.01) and increased markedly during lactation; this increase was much larger in PL than in lactating-only (LO) rabbits (P<0.01). Milk output was similar between PL and LO does during the first 21 d of lactation but a marked decline in this parameter occurred in PL does from then until 30 d. The differences in nest-building between PL and PO rabbits may be related to the concentrations of estradiol and progesterone on specific days of pregnancy. PL does showed significantly higher estradiol levels than PO animals on pregnancy 1 d (33±13 vs. 23±4 pg/mL; P<0.02) and 21 (34±19 vs. 24±6 pg/mL; P<0.05) and also higher levels of progesterone on pregnancy 1 d (4±5 vs. 1±2 ng/mL; P<0.05). However, PL rabbits had lower levels of progesterone on 7 d (6±3 vs. 9±2 ng/mL; P<0.02) and 14 d (8±3 vs. 11±3 ng/mL; P<0.005) than PO does. Our results indicate that the unique endocrine milieu of PL rabbits has a direct bearing on specific behavioral and physiological phenomena that impact productivity on the farm.González-Mariscal, G.; Gallegos, J.; Sierra-Ramírez, A.; Garza Flores, J. (2009). Impact of concurrent pregnancy and lactation on maternal nestbuilding, estradiol and progesterone concentrations in rabbits. World Rabbit Science. 17(3):145-152. doi:10.4995/wrs.2009.65414515217

Aerospace industry in Queretaro, Mexico: a perspective of regional innovation system

Using the theoretical perspective of the Regional Innovation System (RIS), this paper analyzes the structure of the aerospace industry in Mexico, focusing on the region of Querétaro, Mexico. The objective of the research is to analyze the development, growth prospects , key agents and their interrelations of the aerospace industry in the Queretaro region from the perspective of the RIS. The aerospace industry in Querétaro has more than 40 companies, research centers and universities, intermediate and government agencies that focus on the aerospace industry, the region has presented rates of economic growth above the national average in the last 6 years, however to achieve the consolidation of the aerospace industry towards an RIS requires greater efforts of articulation and coordination among the agents that make up the system, it can be achieved through strategies and policies in joint collaboration for the consolidation of the industry in the region.N/

Assessing systematic literature review bias: kaizen events in hospitals case study

A systematic literature review (SLR) is a protocol used to identify publications, select relevant publications, collect data, conduct scientometric analyses, and report research results (SLR outcomes or findings). Despite the increasing use of SLR to assess the maturity or evolution of a research field, as Engineering Management, there are a limit number of publications focused to test SLR biases. Therefore, the purposes of this investigation are to test search field bias (precise SLR vs. sensitive SLR) and to identify statistically significant differences between SLR outcomes. In order to achieve these goals, a three steps methodology was used in three platforms/databases. First, a precise SLR in ProQuest (search terms only in abstract) was conducted to identify publications describing a single Kaizen event in a hospital. From these publications, five metrics were assessed: new authors per year, number of authors per paper, number of publications per year, Kaizen event duration (days), and number of tools used during the Kaizen event per paper. Second, a sensitive SLR in ProQuest (search term in full text) was conducted using the same search terms, exclusion criteria, and metrics from the first step. Third, t-test hypotheses were conducted in SPSS version 20 to identify statistically significant difference for each metric between precise SLR vs. sensitive SLR. The same three steps were used in two more platforms/databases: EBSCOhost and Scopus. Initial results from this ongoing investigation show statistically significant differences between precise SLR and sensitive SLR for some of the five metrics assessed, such as the number of publications per year. Final results will be available in November 2018.N/

Prevalence of colonizing bacteria and their association with primary bacteremias in hemodialysis of a university hospital

to be from 2.5 to 5.5 cases per 1,000 catheter-day. the clinical impact is relevant and increases the cost of the HD Unit. Methods: The present study is the irst of 2 phases. It was conducted from January to December of 2012, and included all patients and nurses who were in the HD Unit. The prevalence of Gramnegative bacilli (GNB) and methicillin-resistant Staphylococcus aureus (MrSA) colonizing the nasal passages and the skin is described. Also, phenotypic association was sought by genus, species and sensitivities between colonizing bacterial strains and blood cultures with GNB and MRSA. Results: the study included 70 patients and 10 nurses. the prevalence of nasal colonization in patients by GNB was 9% and 6% in the pericatheter, and no nursing GNB colonization was discovered. The prevalence of MRSA nasal colonization was 19% and 6% in the pericatheter for patients and in the nurses the nasal colonization was 50% and 10% in the hands. We identiied 29 cases of primary bacteremia. The primary bacteremia rate is 1.5 per 1,000 catheter-day or 0.4 episodes per patient per year. Conclusion: We demonstrated a high prevalence of MrSA colonization in patients and nurses in the HD Unit. No relationship was found between primary bacteremia by GNB and patients and nurses’ bacteria colonization by the phenotypic comparison

Assessment of the toll-like receptor 4 Asp299Gly, Thr399Ile and interleukin-8 -251 polymorphisms in the risk for the development of distal gastric cancer

<p>Abstract</p> <p>Background</p> <p>The intensity of the inflammation induced by <it>Helicobacter pylori </it>colonization is associated with the development of distal gastric cancer (GC). The host response to <it>H</it>. <it>pylori </it>has been related to genetic polymorphisms that influence both innate and adaptive immune responses.</p> <p>Our aim was to investigate whether the presence of the <it>TLR4 Asp299Gly</it>, <it>TLR4 Thr399Ile </it>and <it>IL-8-251 </it>A/T polymorphisms had any influence in the development of distal GC in a Mexican population.</p> <p>Methods</p> <p>We studied 337 patients that were divided in two groups: 78 patients with histologically confirmed distal GC and 259 non-cancer controls. The presence of <it>H. pylori </it>in the control population was defined by positive results of at least two of four diagnostic tests: serology, histology, rapid urease test and culture. Human DNA was purified and genotyped for <it>TLR4 Asp299Gly </it>polymorphism by pyrosequencing, for <it>TLR4 Thr399Ile </it>by PCR-RFLP and for <it>IL8-251 </it>by the amplification refractory mutation system (ARMS)-PCR.</p> <p>Results</p> <p>The non-cancer control group was found to be in Hardy-Weinberg equilibrium at the polymorphic loci studied (chi-square _H-W= 0.58 for <it>IL8-251</it>, 0.42 for <it>TLR4 Asp299Gly </it>and 0.17 for <it>TLR4 Thr399Ile</it>). The frequencies of mutated alleles (homozygous plus heterozygous) were compared between cases and controls. We found no significant difference for <it>TLR4- Asp299Gly </it>[the 7.7% of distal GC patients and 7.7 % non-cancer controls (p = 0.82)] and for <it>TLR4 Thr399Ile </it>[the 1.3% of GC patients and the 5% of the control population (p = 0.2)]. In contrast, for <it>IL-8-251 </it>A/T, 80.77% of the GC patients and 66.4% in the control group age and gender matched had at least one copy of mutated allele (OR = 2.12, 95% CI = 1.1–4.2) (p = 0.023).</p> <p>Conclusion</p> <p>This study showed that the <it>IL8-251*A </it>allele could be related to the development of distal gastric cancer in this Mexican population.</p

Biomarcadores moleculares en la predicción de sarcopenia

A lo largo de la vida se presentan diferentes cambios a nivel de composición corporal, siendo más notorios durante el proceso de envejecimiento. La sarcopenia se define como la pérdida progresiva y constante de la masa muscular magra así como la función y la fuerza del músculo esquelético. Se presenta como un proceso del envejecimiento, en el que el cuerpo experimenta un deterioro progresivo de calidad, reducción de tamaño, número de las fibras musculares, colágeno, modificación de unidad motora que se ha relacionado con el aumento de porcentaje de grasa, cambios hormonales, mecanismos inflamatorios, estrés oxidativo, ingesta de proteínas y actividad física. El envejecimiento puede ser considerado como la resistencia de varios estímulos anabólicos al músculo (sistema nervioso central [SNC], hormona del crecimiento, estrógeno, testosterona, proteína dietética, actividad física, acción de insulina) y posiblemente el desarrollo de varios procesos catabólicos naturales del mismo (inflamación subclínica, producción de citoquinas catabólicas: factor de necrosis tumoral- [TNF- -6 [IL-6], interleucina- - -1, IL- s causas de la sarcopenia todavía no se comprenden claramente, existen muchos mecanismos potenciales que han sido investigados en mayor o menor medida, como la edad, las relacionadas a la enfermedad, nutrición y actividad física. Los criterios para identificar a la sarcopenia incluye la cantidad, función muscular y el rendimiento físico, lo cual, si se llegaran a integrar biomarcadores moleculares en la evaluación clínica, el diagnóstico podría efectuarse de una manera temprana, para evitar la complicaciones asociadas a la fragilida

Cytological effects of pulsed electromagnetic fields and static magnetic fields induced by a therapeutic device on in vivo exposed rats

Background: There is a trend towards the use of magnetic fields in medicine. Pulsed electromagnetic fields (PEMFs) technology was based upon 20 years of fundamental studies on the electromechanical properties of bone and other connective tissues. More recently, these magnetic fields have been used to treat several health conditions. There remains continuing concern that exposure to electromagnetic devices may cause adverse effects. The aim of the present study was to investigate the cytological effects induced in rats exposed in a patented medical device that uses PEMFs combined with static magnetic fields (SMFs).Material and Methods: Thirty sexually mature 14-week-old male and female Sprague Dawley rats were distributed into three groups: (a) 5 males and 5 females (independently) exposed to PEMFs combined with SMFs, (b) animals treated with SMFs only, and (c) non-exposed animals. Acridine orange fluorescent-staining micronucleus test and male germ cells analysis were performed according to standardized techniques.Results: A lack of evidence for alterations on micronucleus frequency, on polychromatic erythrocytes percentage, and on sperm counts and morphological characteristics of male germ cells were found in mature rats exposed to PEMFs medical device compared to non-exposed animals.Conclusions: This study suggests that the applied magnetic field generated in a therapeutic device did not have any detectable cytotoxic or genotoxic effect in exposed rats. In view of these findings and the contradictory reports in the literature, it is necessary to carry out more research to help clarify the controversy concerning cytogenotoxic risk associated with therapeutic magnetic fields exposures.Keywords: Cytotoxicity, pulsed electromagnetic fields, static magnetic fields, micronuclei, sperm abnormalitie

Exploración de opciones agroecológicas en el sistema de milpa de la Costa Chica, México

Los sistemas de producción de la Costa Chica enfrentan serios problemas de degradación del suelo y baja productividad de maíz y jamaica. Esta situación demanda el diseño e implementación de alternativas agroecológicas para revertir esta problemática. Diversos protocolos experimentales que incluyeron opciones de fertilización e integración de leguminosas se desarrollaron en milpas de agricultores. Con base en los resultados encontrados se realizaron exploraciones a través de modelaje para evaluar el impacto de esas alternativas en el rendimiento de maíz y en el balance de materia orgánica a nivel sistema de producción. Los resultados demostraron que la integración de los componentes evaluados (fertilización, leguminosas y retención de residuos) tuvo efectos positivos en los ingresos familiares y en el balance de materia orgánica.Farming systems in Costa Chica, Mexico face problems related to soil degradation and low crop productivity. This situation requires designing and implementing agroecological alternatives to improve cropping systems. Several experimental trials that included fertilization and intercropping of legumes in current milpa systems were carried out in farmers´ fields. Based on the results modeling explorations were carried out to evaluate the impacts of these field-level agroecological options at farm level. The results showed that the integration of the evaluated components (fertilization, legumes and crop residues retention) had positive effects on family income and organic matter balances.Eje A1 Sistemas de producción de base agroecológica (Trabajos científicos)Facultad de Ciencias Agrarias y Forestale

LOS CAMPOS ELECTROMAGNÉTICOS: ¿UN PROBLEMA DE SALUD PÚBLICA?

En la presente revisión, se da una aproximación al contexto actual sobre la controversia que se hadado acerca del riesgo potencial que representa el estar sometido a la influencia de camposmagnéticos y si esto podría llegar a convertirse en un problema de salud pública. Los resultados delas investigaciones aquí presentadas, sugieren que los campos magnéticos son capaces demodificar actividades celulares, y que esto debe ser considerado en la estimación del riesgopotencial que representa una exposición laboral o ambiental a estos agentes físicosPalabras clave: campos electromagnéticos, salud pública Electromagnetic field, Public healt