Scale-up of hydrothermal processing: Liquid hot water and pilot-scale tubular steam explosion batch reactor for bioethanol production using macroalgae Sargassum spp biomass.

Sargassum spp. is a biomass that can potentially use as an alternative for bioethanol production. Hydrothermal processes (liquid hot water and steam explosion pretreatment) were carried out at different operational conditions. Enzymatic hydrolysis performed a preliminary test with different ratios 1:1 and 1:2 (cellulases and hemicellulases) of enzyme loading, once selected 1:2 ratio was obtained conversion yield of 99.91% and therefore carried a scale-up in stirred bioreactor getting 95.92% saccharification yield. Pre-simultaneous saccharification and fermentation strategy was performed in a continuous stirred tank bioreactor (CSTBR), producing ethanol yield of 57.69%, and for simultaneous saccharification and fermentation strategy was performed in a bubble column reactor was 71.37% ethanol yield. The energy efficiency was analyzed in different scenarios; the best data was 30.19 (gsugar/MJ) in the bioreactor enzymatic hydrolysis process. This development allows for establishing the conditions for a third-generation biorefinery on a circular bioeconomy using Sargassum biomass.

Inducing a topological transition in graphene nanoribbon superlattices by external strain.

Armchair graphene nanoribbons, when forming a superlattice, can be classified into different topological phases, with or without edge states. By means of tight-binding and classical molecular dynamics (MD) simulations, we studied the electronic and mechanical properties of some of these superlattices. MD shows that fracture in modulated superlattices is brittle, as for unmodulated ribbons, and occurs at the thinner regions, with staggered superlattices achieving a larger fracture strain than inline superlattices. We found a general mechanism to induce a topological transition with strain, related to the electronic properties of each segment of the superlattice, and by studying the sublattice polarization we were able to characterize the transition and the response of these states to the strain. For the cases studied in detail here, the topological transition occurred at ∼3-5% strain, well below the fracture strain. The topological states of the superlattice - if present - are robust to strain even close to fracture. The topological transition was characterized by means of the sublattice polarization of the states.

Genetic diversity of Chlamydia pecorum detected in sheep flocks from Mexico.

Chlamydia pecorum, an obligate intracellular bacterium, is associated with reproductive and systemic diseases in sheep, goats, pigs, cattle, and koalas. The main conditions include polyarthritis, conjunctivitis, enteritis, pneumonia, encephalomyelitis, orchitis, placentitis, and abortion. Even though there are several studies showing that C. pecorum infections are widely spread in the world, in Mexico there are no reports. During 2016, as part of a sheep restocking program in Mexico, sheep were imported from New Zealand. Briefly after their arrival in the herds in the State of Mexico, these sheep presented abortions during the last third of gestation. A total of 62 sheep vaginal swabs that had presented abortion from different municipalities of the State of Mexico were collected. Bacterial isolation was performed using L929 mouse fibroblasts, and molecular identification was achieved by 23S rRNA (Chlamydiaceae family) and ompA gene (species-specific) real-time polymerase chain reaction (PCR). In addition, the 16S rRNA subunit and ompA gene were amplified and sequenced. Seven of 62 samples were positive for C. pecorum by bacterial isolation, 23S rRNA, and ompA gene real-time PCR. The 16S rRNA subunit and ompA gene amplicons were purified and the nucleotide sequence was determined in both directions. The consensus sequences homology search was performed using BLASTn analysis and showed a 100% of homology with the C. pecorum 16S rRNA subunit and 99% with the C. pecorum ompA gene. The population structure analyses using ompA gene demonstrated 15 genetic populations or clusters of 198 sequences from GenBank and our sequences were in a particular genetic structure corresponding to genotype "O." Herein, we describe the presence of C. pecorum in sheep imported from New Zealand into Mexico. Genetic analysis of the ompA gene showed that the isolates belong to genotype O and are related to strains isolated from sheep, cattle, and koalas.

High-pressure technology for Sargassum spp biomass pretreatment and fractionation in the third generation of bioethanol production.

Sargassum spp is an invasive macroalgae and an alternative feedstock for bioethanol production. Sargassum spp biomass was subjected to high-pressure technology for biomass fractionation under different operating conditions of temperature and residence time to obtain glucan enriched pretreated solids (32.22 g/100 g of raw material). Enzyme hydrolysis process at high pretreated solid loading (13%, w/v) and enzyme loading of 10 FPU/g of glucan was performed, obtaining 43.01 g/L of glucose corresponding to a conversion yield of 92.12%. Finally, a pre-simultaneous saccharification and fermentation strategy (PSSF) was performed to produce bioethanol. This operational strategy produced 45.66 g/L of glucose in the pre-saccharification stage, and 18.14 g/L of bioethanol was produced with a glucose to bioethanol conversion yield of 76.23%. The development of this process highlights the feasibility of bioethanol production from macroalgal biomass in the biorefinery concept.

Simulated mechanical properties of finite-size graphene nanoribbons.

There are many simulation studies of mechanical properties of graphene nanoribbons (GNR), but there is a lack of agreement regarding elastic and plastic behavior. In this paper we aim to analyze mechanical properties of finite-size GNR, including elastic modulus and fracture, as a function of ribbon size. We present classical molecular dynamics simulations for three different empirical potentials which are often used for graphene simulations: AIREBO, REBO-scr and REAXFF. Ribbons with and without H-passivation at the borders are considered, and the effects of strain rate and different boundaries are also explored. We focus on zig-zag GNR, but also include some armchair GNR examples. Results are strongly dependent on the empirical potential employed. Elastic modulus under uniaxial tension can depend on ribbon size, unlike predictions from continuum-scale models and from some atomistic simulations, and fracture strain and progress vary significantly amongst the simulated potentials. Because of that, we have also carried out quasi-static ab-initio simulations for a selected size, and find that the fracture process is not sudden, instead the wave function changes from Blöch states to a strong interaction between localized waves, which decreases continuously with distance. All potentials show good agreement with DFT in the linear elastic regime, but only the REBO-scr potential shows reasonable agreement with DFT both in the nonlinear elastic and fracture regimes. This would allow more reliable simulations of GNRs and GNR-based nanostructures, to help interpreting experimental results and for future technological applications.

Evaluation of pro- and anti-inflammatory interleukins in the mammary gland of goats experimentally infected with Staphylococcus chromogenes.

The aim of this work was to evaluate the relative gene expression levels of the cytokines IL- 1B, IL-8, IL-12, IFN-γ, IL-4, IL-10 and TGF-ß in somatic milk cells of French Alpine breed, anestrous goats that were experimentally infected in the left mammary gland with Staphylococcus chromogenes during the lactation peak. Milk samples were obtained from both glands for 21 consecutive days post infection. Total RNA was extracted, and real-time PCR was conducted using primers specific to each cytokine. The relative RNA expression of the evaluated cytokines was determined by the comparative method 2-ΔΔCT, using milk from the right gland of the goats as a reference (control) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an endogenous control. According to the Wilcoxon test results, IL-1B and IL-12 expression levels showed significant differences compared to those in the control group (p⟨0.05) from 24 hours post infection until the end of lactation; on day three, IL1ß, IL8, IL12 and TGF-ß had a statistically significant change in expression with respect to those in the control group (p⟨0.05); closer to the end of the lactation period, there is no overexpression of the anti-inflammatory interleukins (IL-4 and TGF-ß) which may reflect the effort of the host immune system to eradicate the microorganism from the mammary gland.

Bloqueo del nervio infraorbitario. Realidades sobre su uso en odontología / Infraorbital nerve block. Realities about its use in dentistry

Objetivos: Los autores realizaron un ensayo clínico, aleatorizado, ciego simple, en el cual se determinó la eficacia del bloqueo del nervio infraorbitario en la anestesia de premolares maxilares comparándola con la técnica alveolar media superior. Materiales y métodos: Treinta sujetos voluntarios recibieron 1,8 mililitros de lidocaína al 2% con epinefrina 1:80.000. Los investigadores evaluaron el grado de anestesia pulpar con vitalómetro, dolor a la punción, inicio y duración del efecto anestésico, anestesia de tejidos blandos y comodidad del paciente ante esta anestesia. Los datos se analizaron usando la prueba de Shapiro Wilk, Mann-Whitney y McNemar. Resultados: La anestesia pulpar profunda en la técnica alveolar media fue significativamente mayor al compararla con la técnica infraorbitaria en el primer y segundo premolar, siendo del 95,2% y 100% respectivamente para la técnica alveolar media y del 66,7% y 42,9% en la técnica infraorbitaria. Los autores notaron significancia estadística en cuanto a la percepción del dolor asociado a la inyección, siendo la técnica infraorbitaria más dolorosa (p= 0,003). El inicio del efecto anestésico fue más corto después de aplicar la técnica alveolar media y la duración del efecto anestésico fue significativamente mayor en la misma técnica. La incidencia de anestesia subjetiva en labios, piel de ala nariz y encía fue del 100 % para la técnica infraorbitaria, reportando un mayor grado de incomodidad por la anestesia de los tejidos blandos en esta técnica. Conclusiones: La técnica alveolar media superior demostró ser más eficaz en la anestesia pulpar de premolares superiores al compararla la técnica infraorbita (AU)

Objective: The authors conducted a clinical trial, randomized, single blind to compare the efficacy of the infraorbital nerve block with the middle superior alveolar technique in achieving pulpal anesthesia of maxillary premolars. Material and Methods: Thirty volunteers subjects received 1.8 milliliter of 2 percent of lidocaine with 1:80.000 epinephrine. Researchers assessed the degree of pulpal anesthesia with an electronic pulp testing, puncture pain, soft-tissue anesthesia and patient comfort at this anesthesia, start time and duration of anesthetic effect. The data was analyzed by using the Shapiro-Wilk, Mann-Whiitney and McNemar tests. Results: Pulpal anesthesia deep in the middle superior alveolar technique was significantly higher when compared to the infraorbital technique in the first and second premolar, this being 95.2% and 100% respectively for the middle superior alveolar technique and 66.7% and 42.9% in the infraorbital technique. The authors noted statistical significance in the perception of pain associated with the injection, the most painful technique was the infraorbital (p= 0.003). The onset of the anesthetic effect was shorter after applying the middle superior alveolar technique and the duration of anesthetic effect was significantly higher in the same technique. The incidence of subjective anesthesia of lips, skin, wing nose and gum was 100% for the infraorbital technique, reporting greater discomfort for the soft tissue anesthesia in this technique. Conclusions: The middle alveolar superior technique proved more effective in achieving pulpal anesthesia of maxillary premolars with respect to the infraorbital technique (AU)

Characterisation of quinolone-resistant Escherichia coli of 1997 and 2005 isolates from poultry in Mexico.

Forty-two enrofloxacin-resistant Escherichia coli strains isolated from eggs and first-week mortality associated with yolk sac infection of two vertically integrated poultry companies of Central Mexico in 1997 and 2005 were characterised. E. coli resistance to 19 antibiotics was determined, as well as the minimum inhibitory concentrations (broth dilution) for ciprofloxacin. The presence of gyrA,B, parC,E chromosomal point mutations, qnrA,B,S plasmid genes and the aminoglycoside acetyltransferase aac(6')-Ib-cr were determined by PCR and sequencing. Resistance to ampicillin (95%), piperacillin (95%), gatifloxacin (95%), levofloxacin (95%), ampicillin/sulbactam (90%), cefazolin (85%), trimethoprim/sulfamethoxazole (80%), amoxicillin/clavulanic acid (80%), aztreonam (80%), cefepime (80%), cefotaxime (80%), ceftazidime (80%), ceftriaxone (80%) and cefoxitin (75%) was high in the 2005 strains and 19 (95%) strains were resistant to 7 or more antimicrobials. The strains from 1997 expressed high rates of resistance only to the fluoroquinolones and 4 strains (18%) expressed resistance to 7 or more antimicrobials. All strains had a gyrA mutation (Ser83Leu) and a parC mutation (Ser80Ile or Ser80Arg) and 41 (97.6%) strains had a second gyrA mutation (Asp87Asn, Asp87Tyr or Asp87Gly). Only two (4.7%) strains had a parE mutation (Ser458Ala). A total of 10 strains were positive for the aac(6')-Ib wild-type gene, 6 strains for the aac(6')-Ib-cr variant and 6 strains possessed both the wild type and the variant. No gyrB mutations or qnrA,B,S genes were detected. This is the first report in Latin America of chromosomal and plasmid quinolone resistance genes in E. coli strains recovered from poultry.

Accidentes más comunes en las Unidades de Cuidados Intensivos Pediátricos (UCIP) / Most common accidents in the Pediatric Intensive Care Units (PICU)

No disponible

The role of emotion regulation in childhood obesity: implications for prevention and treatment.

Stress and negative emotions pose a major threat to public health, by increasing the risk of obesity. Since the management process for emotions (emotion regulation; ER) is developed in childhood, we present a novel conceptual framework model for the role of ER in the prevention and treatment of childhood obesity. A narrative review of the literature by electronic database search (MEDLINE, Web of Knowledge and Scopus) was conducted of observational and interventional/experimental literature on ER and obesity and the underlying concepts. We also present an overview of ER intervention techniques. Our model indicates that childhood ER is a link between stress and obesity. Stress along with ineffective ER leads to abnormal cortisol patterns, emotional eating, sedentary lifestyle, reduction of physical activity, and sleep problems. Simultaneously, a healthy lifestyle could show benefits on ER and in developing adaptive ER strategies. In the development of obesity and ER, parents also play a role. By contrast, effective ER skills decrease obesity-related unhealthy behaviour and enhance protective factors, which boost health. The literature contains some observational studies of children but very few intervention studies, most of which are pilot or on-going studies. In conclusion, encouraging effective ER could be a useful new approach for combating and treating childhood obesity. Future ER intervention studies are needed to confirm the validity of this model in children.

Epidemiology of brucellosis in domestic animals caused by Brucella melitensis, Brucella suis and Brucella abortus.

Brucellosis is a disease that causes severe economic losses for livestock farms worldwide. Brucella melitensis, B. abortus and B. suis, which are transmitted between animals both vertically and horizontally, cause abortion and infertility in their primary natural hosts - goats and sheep (B. melitensis), cows (B. abortus) and sows (B. suis). Brucella spp. infect not only their preferred hosts but also other domestic and wild animal species, which in turn can act as reservoirs of the disease for other animal species and humans. Brucellosis is therefore considered to be a major zoonosis transmitted by direct contact with animals and/or their secretions, or by consuming milk and dairy products.

Natural prevalence of HCV minority variants that are highly resistant to NS3/4A protease inhibitors.

Minority drug-resistant hepatitis C virus (HCV) variants may go undetected yet be clinically important. NS3/4A protease resistance substitutions V36A and A156S/T/V were selected in patients treated with protease inhibitors. The aim of this study was to investigate whether these substitutions pre-existed in HCV infected patients. An allele-specific PCR protocol that detected the NS3/4A protease resistance substitutions V36A and A156S/T/V was used to determine the prevalence of naturally occurring variants in 45 patients. All patient samples were infected with HCV of genotype 1b and were naïve for pegIFNα/ribavirin treatment. Thirty samples (67%) had at least one HCV PI-resistant variant. A156T (23, 51%) was detected more frequently than A156V (13, 29%) or A156S (1, 2%). V36A was detected in 12 samples (27%). These results demonstrate the high prevalence of minority drug-resistant NS3/4 protease resistance substitutions. Our results also demonstrate that allele-specific PCR can be used to detect minor HCV NS3 protease resistant variants in pretreatment samples and to study in detail the evolution of mutant viruses during targeted antiviral therapy.

Improved performance of Brucella melitensis native hapten over Brucella abortus OPS tracer on goat antibody detection by the fluorescence polarization assay.

The current method for goat brucellosis diagnosis is based on the World Organization for Animal Health (OIE) using the screening card test (CT), with antigen at 8% (CT8) or 3% (CT3) of cell concentrations, and the confirmatory complement fixation test (CFT). However, these tests do not differentiate antibodies induced by vaccination from those derived from field infections by Brucella species or other bacterial agents; in places like Mexico, where the prevalence of brucellosis and the vaccination rates are high, there is a considerable percentage of false positive reactions that causes significant unnecessary slaughter of animals. Furthermore, results of the fluorescence polarization assay (FPA) using the Brucella abortus O-polysaccharide (OPS) tracer in goats are poorer than those with cattle. The present study was undertaken to investigate a tracer prepared from the native hapten (NH) of the Rev. 1 strain of Brucella melitensis to improve FPA performance on goat brucellosis diagnosis. Evaluation of 48 positive samples and 96 negative samples showed that the NH tracer was more accurate (p<0.01) than the OPS tracer (97.2% vs. 93.8% accuracy, respectively). On the diagnostic performance evaluation, the NH tracer performed better (87.5% accuracy, 79.5% sensitivity, 84.3% specificity, and 163.8 performance index) than the OPS tracer (83.5%, 75.9%, 81.0%, and 156.9, respectively) using 1009 positive and 2039 negative Mexican field goat sera samples selected by test series approved by the OIE (card test 3% and CFT). We demonstrated a new application for the NH lipopolysaccharide on detecting antibodies against Brucella using the FPA, which may yield faster results (minutes vs. 24-72h) than the immunodiagnosis assays frequently used in bovine brucellosis. In addition, NH tracer produces similar or better performance results than the conventional OPS tracer, using the FPA in goat sera samples.

Evaluación y análisis del morfotipo raquídeo del futbolista juvenil y amateur / Evaluation and analysis of spine morpho-type of the amateur and juvenile football player

Se realiza un análisis del morfotipo raquídeo de jóvenes futbolistas (n = 100) pertenecientes a las categorías juvenil y amateur (16-25 años) de dos escuelas de fútbol de Salamanca, comparando los resultados con los correspondientes a un grupo de "no deportistas", compuesto por universitarios (n = 37) de similar edad que no practican deporte reglado. Mediante una valoración fisioterápica, se obtienen las flechas sagitales cervical y lumbar y se evalúa el grado de flexibilidad y elasticidad miotendinosa de la cadena muscular cinética recta posterior (CRP) a través de las siguientes pruebas: test de Ott; test de Schöber; test de flexión en bipedestación o "distancia dedos-suelo" (DDS); y test de flexión en sedestación o "sit and reach". Los datos son anotados en un ficha proforma individual para su posterior análisis. Los resultados obtenidos determinan un morfotipo raquídeo característico del futbolista juvenil y amateur en el que aparece una tendencia a la hiperlordosis lumbar (5,5 ± 1,1 cm); una mayor flexibilidad analítica del raquis lumbar (5,8 ± 0,7 cm) y una mayor elasticidad global de la CRP (1,8 ± 9,3 cm en el test DDS y 3,7 ± 9,4 cm para el test "sit and reach"), respecto a los individuos "no deportistas" (4,8 ± 0,9 cm; 5,1 ± 1,0 cm; ­3,7 ± 10,0 cm; y 0,0 ± 9,4 cm respectivamente). Asimismo, el análisis comparativo de los resultados obtenidos en los test DDS y test "sit and reach" (numéricamente superiores en todos los casos para el test en sedestación), pone de manifiesto la importante influencia de la extensibilidad de los elementos capsuloligamentosos y de la elasticidad de las estructuras miofasciales sobre la valoración de la elasticidad global de la CRP

It is carried out an analysis of spine morpho-type of young players (n = 100) from juvenile and amateur categories (from 16 to 25 years) belonging to two football schools in Salamanca. The results are compared with those from a group of "non-players" madep up of university students (n = 37) of similar age who practice no ruled sport. By means of a physiotherapic valuation, the sagital arrows of cervical and lumbar bow are obtained and it is evaluated the degree of flexibility and elasticity of myo-tendon structure of the posterior kinetic muscular chain (CRP) through the following tests: Ott's test, Schöber's test, biped flexión test or "toes-ground distance"(DDS) and "sit and reach" test. Data are written down in an individual register to their later analysis. The results determine a characteristic spine morpho-type of the juvenile and amateur football player where appears a tendency towards lumbar hyperlordosis (5,5 ± 1,1 cm); a higher analytic flexibility of lumbar spine (5,8 ± 0,7 cm) and a higher global elasticity of the CRP (1,8 ± 9,3 cm at DDS test and 3,7 ± 9,4 cm at the"sit and reach"test) comparing them with non-players-individuals (4,8 ± 0,9 cm; 5,1 ± 1,0 cm; ­3,7 ± 10,0 cm; and 0,0 ± 9,4 cm respectively). In the same way, the comparative analysis of the results obtained at DDS test and "sit and reach" test (numerically higher in all cases for the "sit and reach" test) shows the important influence of the capsule-ligaments elements' spreadability and the myo-fascial structures' elasticity implied at the valuation of the global elasticity of the CRP

Subcellular fractions of Brucella ovis distinctively induce the production of interleukin-2, interleukin-4, and interferon-gamma in mice.

The aim of this study was to evaluate the effect of 3 Brucella ovis subcellular protein fractions: Outer membrane (OMP), inner membrane (IMP), and cytoplasm (CP), on cellular immune response by in vitro production of interleukin (IL)-2, IL-4, and interferon (IFN)-gamma. Each fraction was inoculated 3 times into Balb/c mice, primary cultures of mice spleen cells were done, and these were then stimulated with the fractions. Culture supernatants were collected at 24, 48, 72, 96, and 120 h postinoculation. Cytokine concentration was measured by Duoset-enzyme-linked immunosorbent assay (ELISA). The OMP fraction induced highest cellular immune response of 1000 pg/mL of IL-2 at 24 h, which decreased to < 100 pg/mL by 96 h. The IL-2 response for the IMP fraction was low at 24 h, but exceeded that of the OMP fraction at 72, 96, and 120 h. The CP showed a poor IL response. Regarding the IFN-gamma production, OMP and IMP induced a high response at 120 h. These results open the possibility for the use of B. ovis outer and inner membrane proteins as a subcellular vaccine.

Influencia del tipo de jornada escolar en el peso de las mochilas escolares / Influence of the kind daily school stage in the weight pupils rucksacks

Objetivos. El objetivo del presente trabajo es analizar el peso que los escolares entre 8 y 12 años transportan en sus mochilas, y si éste está en relación con la distribución de la jornada diaria escolar. Se pretende también conocer las preferencias de los escolares a la hora de transportar el material escolar. Material y método. El estudio se lleva a cabo en dos Colegios de Primaria de la ciudad de Salamanca, uno de ellos con jornada única o continua (sólo mañanas) y otro con jornadas de mañana y tarde (jornada partida). Participan en el mismo todos los alumnos de 3.º, 4.º, 5.º y 6.º curso de ambos centros. Los estudiantes fueron pesados con y sin mochilas y se les realizó una pequeña encuesta que incluía distintas preguntas abiertas sobre el tipo de mochila, la forma de trasportarla y el modo de llegar al colegio. Así mismo se realizó otra encuesta a los profesores de los distintos cursos sobre su opinión en el tema de estudio. Resultados. El número total de alumnos estudiados es 203, su edad media es de 9,77 ± 1,279 años y su peso corporal medio es de 38,8 ± 9,15 kg. El peso medio de la mochila de los escolares es 3,91 ± 2,16 kg, siendo superior en los estudiantes del colegio de jornada continuada y estableciéndose diferencias estadísticamente significativas. La relación entre el peso del niño y el peso de la mochila presenta una media de 8,91 ± 4,58 %; del total de la muestra sólo el 23 % transporta una mochila sobrecargada, si bien, este porcentaje supera el 50 % en el colegio de jornada continua, estableciéndose diferencias significativas entre los dos centros. Conclusiones. La distribución en la jornada escolar (jornada continua-jornada partida) repercute directamente en el peso de las mochilas, pudiendo este hecho ser un factor de riesgo en la patología vertebral propia de los escolares

Objectives. The main object of this work is to analyse the weight that pupils between 8 and 12 years carry on their rucksacks, and if is related to the allocation of the daily school stage. It is tried to know the pupils’ preferences when they carry their school equipment, as well. Material and methods. This study carry out in two Primary School in Salamanca, once with full working day (mornings only) and the other with split shift (mornings and afternoons). The students of 3.º, 4.º, 5.º, and 6.º classes of both centres take part in this study. The students were weighing with and without rucksack, and a little survey which included differents open questions about the kind of rucksack, the way of carry it and the way taht they go to the school. Another survey was doing to the teachers about their opinions to this study subject so as. Results. The whole pupils studied is 203, their ages among is 9,77 ± 1,279 years, and the average body weight is 38,8 ± 9,15 kg. The average of the rucksack weight is 3,91 ± 2,16 kg, were highter in the full day school pupils, and appear diferences statistically expressive. The relationship between the child weigh and the rucksack weigh present an average of 8,91 ± 4,58 %; of the total of the sample only the 23 % carry a heavy rucksack, althought, this percentage exceeder the 50 % in the full day school, and statistically expressive appear when we compare both centers. Conclusions. The school work allocation (full day work-split shift) directly have repercusions on the rucksack weigh,and its possible that it is a risk factor of typical spine pathology of pupils

Estudio de la postura sedente en una población infantil / Study of the position in a children population

Introducción: El estudio describe la postura sedente que adopta una población infantil durante el periodo de atención al profesor, el cuál comprende la mayor parte del tiempo de las clases en el colegio. Material y método: Se elige al azar una población escolar perteneciente a un colegio público de la ciudad de Salamanca y se observa, de una forma directa, su postura sedente durante el periodo de atención al profesor. Se rellena una ficha para cada sujeto que contiene diferentes parámetros de la postura sedente: tipo de postura, posición de la columna vertebral, apoyo de los pies en el suelo, cruce de piernas y pies, apoyo en el asiento, utilización del respaldo, flexión de rodilla, apoyo asimétrico sobre la mesa, rotación del tronco y posición del cuello. Se realiza un análisis estadístico de los datos comparando la postura sedente que adoptan los sujetos en cada uno de los cursos estudiados y en función del género. Resultados: Los sujetos estudiados son 68 pertenecientes a los cursos de 3.º, 4.º, 5.º y 6.º de primaria, con edades comprendidas entre los 8 años y 7 meses y los 12 años y 7 meses siendo la media 10,38 ñ 1,244, el 48,5 por ciento de ellos niños y el 51,5 por ciento niñas. La postura sedente adoptada con mayores porcentajes es la siguiente: postura sedente media (54,4 por ciento), posición flexionada de la columna vertebral (55,9 por ciento), apoyo de la planta del pie en el suelo (50 por ciento), pies cruzados (55,8 por ciento), apoyo al fondo del asiento (63,2 por ciento), piernas sin cruzar (92,6 por ciento), no utilización del respaldo (47,1 por ciento)-uso correcto del respaldo (41,2 por ciento), flexión de rodillas de más de 90 grados (38,2 por ciento), apoyo de ambos codos sobre la mesa (55,9 por ciento), no rotación del tronco al escribir (52,9 por ciento) y flexión de la columna cervical (42,6 por ciento). Conclusiones: Los niños en edad escolar estudiados no adoptan la postura sedente correcta y recomendada por numerosos autores. Aparecen diferencias en la postura sedente de los niños de la misma clase y entre los diferentes cursos lo que sin duda está en relación con las dimensiones del mobiliario utilizado (AU)