2,967 research outputs found
Fog interception by Ball moss (<i>Tillandsia recurvata</i>)
Interception losses are a major influence in the water yield of vegetated areas. For most storms, rain interception results in less water reaching the ground. However, fog interception can increase the overall water storage capacity of the vegetation and once the storage is exceeded, fog drip is a common hydrological input. Fog interception is disregarded in water budgets of semiarid regions, but for some plant communities, it could be a mechanism offsetting evaporation losses. <i>Tillandsia recurvata</i> is a cosmopolitan epiphyte adapted to arid habitats where fog may be an important water source. Therefore, the interception storage capacity by <i>T. recurvata</i> was measured in controlled conditions and applying simulated rain or fog. Juvenile, vegetative specimens were used to determine the potential upperbound storage capacities. The storage capacity was proportional to dry weight mass. Interception storage capacity (<i>C</i><sub>min</sub>) was 0.19 and 0.56 mm for rainfall and fog respectively. The coefficients obtained in the laboratory were used together with biomass measurements for <i>T. recurvata</i> in a xeric scrub to calculate the depth of water intercepted by rain. <i>T. recurvata</i> contributed 20 % to the rain interception capacity of their shrub hosts: <i>Acacia farnesiana</i> and <i>Prosopis laevigata</i> and; also potentially intercepted 4.8 % of the annual rainfall. Nocturnal stomatic opening in <i>T. recurvata</i> is not only relevant for CO<sub>2</sub> but for water vapor, as suggested by the higher weight change of specimens wetted with fog for 1 h at dark in comparison to those wetted during daylight (543 ± 77 vs. 325 ± 56 mg, <i>p</i> = 0.048). The storage capacity of <i>T. recurvata</i> leaf surfaces could increase the amount of water available for evaporation, but as this species colonise montane forests, the effect could be negative on water recharge, because potential storage capacity is very high, in the laboratory experiments it took up to 12 h at a rate of 0.26 l h<sup>−1</sup> to reach saturation conditions when fog was applied
Necrotizing entercolitis: socio-demographic, clinical and histopathological findings in a series of neonatal autopsies
La enterocolitis necrotizante es un trastorno caracterizado por la necrosis isquémica de la mucosa intestinal, es la enfermedad gastrointestinal más grave que afecta a los neonatos, con alta morbilidad y mortalidad, principalmente en prematuros. El objetivo del presente estudio es describir las características clínicas y anatomopatológicas de los recién nacidos fallecidos con enterocolitis necrotizante, diagnosticados en un hospital de alta complejidad. Metodología. Este es un estudio descriptivo retrospectivo de 21 casos de autopsias médico-científicas hechas en un hospital de alta complejidad del nororiente colombiano, con hallazgos anatomopatológicos de enterocolitis necrotizante, realizadas entre enero de 2013 y julio de 2017. Resultados. El 85.7% de los recién nacidos eran pretérminos, un igual porcentaje presentaba un peso menor a 2,500 gramos al nacer. Respecto a los antecedentes maternos el 14.3% tuvieron espectro de trastornos hipertensivos asociados al embarazo y el 23.8% infección materna. Los tres sitios más frecuentes de ubicación de enterocolitis necrotizantes fue íleon, colon ascendente y colon transverso. Discusión. Según algunos autores, hasta el 85% de todos los casos de enterocolitis necrotizante ocurren en pacientes prematuros, especialmente en bebés con peso extremadamente bajo al nacer. Hay formas de enterocolitis necrotizante que ocurren en bebés a término y, generalmente, están asociadas con factores predisponentes, resultados compatibles con lo que encontramos en esta investigación. Conclusiones. Este estudio elaborado con población colombiana se correlaciona con lo descrito en la población mundial en la cual la enterocolitis necrotizante se presenta más en los recién nacidos pretérmino y con bajo peso al nacer.Necrotizing entercolitis is a disorder characterized by the ischemic necrosis of intestinal mucosa. It is the most serious gastrointestinal disease affecting neonates, with high morbidity and mortality rates, mainly among premature newborns. The purpose of this study is to describe the clinical and anatamo-pathological characteristics of deceased newborns with necrotizing entercolitis, diagnosed at a high-complexity hospital. Methodology. This is a descriptive retrospective study of 21 cases of medical-scientific autopsies performed at a high-complexity hospital in northeastern Colombia, with anatomo-pathological findings of necrotizing entercolitis, performed between January 2013 and July 2017. Results. 85.7% of the newborns were pre-term, and the same percentage had weight at birth below 2.5 kilograms. Regarding the mothers’ background, 14.3% displayed a spectrum of hypertensive disorders associated with pregnancy, and 23.8% had maternal infections. The three most frequent locations of necrotizing entercolitis were the ileum, ascending colon and transverse colon. Discussion. According to some authors, up to 85% of all cases of necrotizing entercolitis occur in premature patients, especially in babies with extremely low weight at birth. There are forms of necrotizing entercolitis that occur in full term babies, and they are generally associated with contributing factors, which is consistent with the findings of this study. Conclusions. This study of a Colombian population is consistent with other descriptions of the global population, where necrotizing entercolitis arises more frequently in pre-term newborns and low weight at birth
Fourier-space generalized magneto-optical ellipsometry
The magneto-optical Kerr effect (MOKE) is widely exploited in laboratory-based setups for the study of thin films and nanostructures, providing magnetic characterization with good spatial and temporal resolutions. Due to the complex coupling of light with a magnetic sample, conventional MOKE magnetometers normally work by selecting a small range of incident wave-vector values, focusing the incident light beam to a small spot, and recording the reflected intensity at that angular range by means of photodetectors. Using this approach, additional methodologies and measurements are required for full vectorial magnetic characterization. Here, we computationally investigate a Fourier-space MOKE setup, where a focused beam ellipsometer using high numerical aperture optics and a camera detector is employed to simultaneously map the intensity distribution for a wide range of incident and reflected wave vectors. We employ circularly incident polarized light and no analyzing optics, in combination with a fitting procedure of the light intensity maps to the analytical expression of the Kerr effect under linear approximation. In this way, we are able to retrieve the three unknown components of the magnetization vector as well as the material' s optical and magneto-optical constants with high accuracy and short acquisition times, with the possibility of single-shot measurements. Fourier MOKE is thus proposed as a powerful method to perform generalized magneto-optical ellipsometry for a wide range of magnetic materials and devices
Conventional vs. tubeless percutaneous nephrolithotomy. Is the urinary diversion really necessary?
Introducción
La nefrolitotomía percutánea (NLP) convencional utiliza derivación con nefrostomía para mejorar el drenaje de orina, facilitar la hemostasia postoperatoria y permitir un trayecto seguro para intervenciones adicionales futuras. Sin embargo, en los últimos años el procedimiento de NLP se ha modificado: ahora permite el retiro del uso del catéter de nefrostomía o de derivación urinaria, procedimiento conocido como tubeless. El presente estudio pretende evaluar la experiencia institucional en cuanto a seguridad, eficacia y ventajas de la NLP tubeless.
Materiales y métodos
Entre agosto de 2012 y mayo de 2014 se reclutó a 51 pacientes del Hospital Universitario San Ignacio y Clínica Fundadores para manejo con nefrolitotomía percutánea. Se incluyó a 49 pacientes con litiasis renal menor de 5cm de diámetro y mayor de 2cm con punción única o múltiple. Se aleatorizaron en 2 grupos: grupo A sin derivación (no nefrostomía no catéter doble J) 26 pacientes, grupo B con derivación (nefrostomía sonda Foley 18 Fr) 23 pacientes. Los desenlaces evaluados fueron: efectividad verificada mediante revisión de imágenes postoperatorias y definida como cálculo residual menor de 5mm, sangrado postoperatorio con medición de hemoglobina durante las primeras 24 h después de cirugía, valoración de dolor con escala visual análoga, necesidad de analgésicos durante las primeras 4 h, cantidad de rescates de analgésico durante las primeras 24 h de cirugía. Los datos se analizaron mediante el paquete estadístico IBM SPSS versión 20, utilizando estadística no paramétrica con la prueba de Wilcoxon Mann-Whitney una vez se determinó que la muestra no tenía una distribución normal. Las variables dicotómicas se analizaron utilizando la prueba de Chi2.
Resultados
Las características de base de los pacientes son comparables: la edad promedio en el grupo A fue de 44,73 años y en el B de 50,26 años (p=0,186), el peso en el grupo A fue de 75,96 kg y en el B de 71,96 kg (p=0,054), el tamaño de los cálculos en el A fue de 28,23mm en promedio y en el B de 29,69mm, sin diferencia estadísticamente significativa (p=0,517). No hubo diferencias significativas en cuanto a efectividad en ambos grupos: en el A el porcentaje de lito residual fue de 1,15% y en el B de 0,87% (p=0,713). No hubo diferencias estadísticamente significativas en cuanto a sangrado postoperatorio (p=0,566), pero sí se observó mayor dolor, requerimiento de analgésicos y mayor número de rescates en los pacientes a los cuales se les dejó derivación mediante nefrostomía.
Discusión
Nuestro trabajo demuestra que la NLP sin derivación urinaria es una técnica segura en aquellos pacientes en los cuales se logra una extracción completa del cálculo, con sangrado comparable a la cirugía convencional y, adicionalmente, con el beneficio de menor dolor y menor requerimiento de analgésico postoperatorio.Q4Artículo original5-9Introduction
Conventional percutaneous nephrolithotomy (PNL) uses a nephrostomy derivation to improve the drainage of urine, facilitate postoperative hemostasis and allow a safe course for future additional surgical interventions. However, in recent years the PNL procedure has been modified to avoid the use of a nephrostomy catheter or any other urinary diversion. This procedure is known as tubeless. This study aims to assess the institutional experience in safety, efficiency and advantages of tubeless PNL.
Materials and methods
Between August 2012 and May 2014, 51 patients were recruited in San Ignacio University Hospital and Fundadores Clinic to be treated with PNL. Forty-nine patients with kidney lithiasis less than 5cm of diameter and greater than 2cm with single or multiple puncture were included. They were randomised into 2 groups: group A no derivation (no nephrostomy catheter, no double J) 26 patients, group B with derivation (18 Fr Foley nephrostomy catheter) 23 patients. The evaluated outcomes were: Effectiveness verified by reviewing postoperative images and defined as a residual stone less than 5mm of diameter, postoperative bleeding with hemoglobin measurement during the first 24h after surgery, pain assessment with the visual analog scale, need for analgesics during the first 4h, amount of analgesic rescues during the first 24h of surgery. Data were analyzed using the statistical package SPSS version 20, using the nonparametric statistical test Wilcoxon Mann-Whitney 11 it was determined that the sample does not have a normal distribution, the dichotomous variables were analyzed using Chi2 test.
Results
Baseline characteristics of patients are comparable: The average age in the group A was 44.73 and 50.26 years in the group B (P=.186), average weight in group A and B was 75.96kg and 71.96kg, respectively (P=.054), the average size of the stones in group A was 28.23mm and 29.69mm in group B with no statistically significant difference (P=.517).
There were no significant differences in effectiveness in both groups, in group A the percentage of residual lithiasis was 1.15% and 0.87% in group B (P=.713). There were no statistically significant differences in postoperative bleeding (P=.566), although pain, analgesic requirement and number of rescues needed were greater in patients who were left with a nephrostomy derivation.
Discussion
Our work shows that percutaneous nephrolithotomy without urinary diversion is a safe procedure in patients in whom a complete stone removal is achieved, with bleeding comparable to conventional surgery, and additionally with the benefit of less pain and less postoperative analgesic requirement
The Education of the System of Documentation for the student of the Pregrate of Q.F.B in the Fes Zaragoza Unam
Introducción. La carrera Química Farmacéutico Biológica (QFB), cuenta con una Planta Piloto
Farmacéutica (PPF) como un recurso del proceso enseñanza-aprendizaje, para el fortalecimiento del
conocimiento donde uno de sus puntos esenciales es la documentación. El Sistema de Documentación
está destinado a que el estudiante desarrolle actividades experimentales y deje evidencia documentada
como lo estipula la reglamentación sanitaria vigente. Objetivo. Presentar la metodología que apoya el
proceso de enseñanza aprendizaje del Sistema de Documentación a los alumnos del área Farmacéutica.
Metodología. Inducción al tema de documentación mediante exposición oral, dando a conocer los
diferentes documentos como son: Manual de laboratorio, Procedimientos Normalizados de Operación,
entre otros. Cada profesor revisa los documentos generados durante el semestre, y sugiere mejoras en
el caso requerido. Resultados. Con base a una evaluación interna, se observa un avance en el
conocimiento y aplicación del Sistema Documental, entre los alumnos de sexto a noveno semestre.
Conclusión. Al poner en práctica lo establecido en los documentos, se contribuye a la disciplina de la
elaboración, difusión y aplicación del Sistema de Documentación, al establecer procesos y flujos que
la conforman.Introduction. The race of Pharmaceutical Biological Chemistry (QFB), has a Pharmaceutical Pilot
Plant (PPF) as a resource in the teaching-learning process for the strengthening of knowledge where
one of his key points is the documentation. The documentation system is designed to enable the
student to develop pilot activities and allow documentary evidence as required by health regulations in
force. Objective. Present the methodology that supports the teaching-learning process Documentation
System for Pharmaceutical area students. Methodology. Induction to the issue of documentation
through oral exposure, revealing the various documents such as: laboratory manual, standard operating
procedures, among others. Each teacher reviews the documents generated during the semester, and
suggest improvements if required. Results. Based on an internal evaluation, there is an advance in
knowledge and implementation of the Documentation System, among students in sixth through ninth
semester. Conclusion. In implementing the provisions of the documents, it contributes to the discipline of the preparation, dissemination and implementation of documentation systems, to establish processes and flows that make it up
Pro-inflammatory-Related Loss of CXCL12 Niche Promotes Acute Lymphoblastic Leukemic Progression at the Expense of Normal Lymphopoiesis
Manual de operación y participación en la Feria internacional de Arte de Chicago One of a Kind Show para el artista plástico Daniel Naredo Betancourt
ITESO, A.C
Nitrogen uptake and internal recycling in Zostera marina exposed to oyster farming: eelgrass potential as a natural biofilter
Oyster farming in estuaries and coastal lagoons frequently overlaps with the distribution of seagrass meadows, yet there are few studies on how this aquaculture practice affects seagrass physiology. We compared in situ nitrogen uptake and the productivity of Zostera marina shoots growing near off-bottom longlines and at a site not affected by oyster farming in San Quintin Bay, a coastal lagoon in Baja California, Mexico. We used benthic chambers to measure leaf NH4 (+) uptake capacities by pulse labeling with (NH4)-N-15 (+) and plant photosynthesis and respiration. The internal N-15 resorption/recycling was measured in shoots 2 weeks after incubations. The natural isotopic composition of eelgrass tissues and vegetative descriptors were also examined. Plants growing at the oyster farming site showed a higher leaf NH4 (+) uptake rate (33.1 mmol NH4 (+) m(-2) day(-1)) relative to those not exposed to oyster cultures (25.6 mmol NH4 (+) m(-2) day(-1)). We calculated that an eelgrass meadow of 15-16 ha (which represents only about 3-4 % of the subtidal eelgrass meadow cover in the western arm of the lagoon) can potentially incorporate the total amount of NH4 (+) excreted by oysters (similar to 5.2 x 10(6) mmol NH4 (+) day(-1)). This highlights the potential of eelgrass to act as a natural biofilter for the NH4 (+) produced by oyster farming. Shoots exposed to oysters were more efficient in re-utilizing the internal N-15 into the growth of new leaf tissues or to translocate it to belowground tissues. Photosynthetic rates were greater in shoots exposed to oysters, which is consistent with higher NH4 (+) uptake and less negative delta C-13 values. Vegetative production (shoot size, leaf growth) was also higher in these shoots. Aboveground/belowground biomass ratio was lower in eelgrass beds not directly influenced by oyster farms, likely related to the higher investment in belowground biomass to incorporate sedimentary nutrients
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