Comparison of round and knife-edge-like cathodes on gas-puff implosions.

Preionization is believed to play an important role on the implosion of gas-puff Z pinches. Some experiments have used an external preionization source, e.g., UV light or electron beam. In contrast, other experiments rely completely on over voltage breakdown by the own generator's voltage pulse. However, this approach lacks shot-to-shot reproducibility since self-breakdown is mainly a stochastic process. In this work, we performed a systematic study on self-breakdown using two different cathode geometries: (i) a smooth, round cathode to provide a homogeneous electric field, (ii) a sharp, knife-edge-like geometry to enhance the electric field locally and eventually electron emission. The experiments were carried out on the Llampudken current generator, which provides a current pulse of ∼400kA amplitude and 200 ns rise time (10%-90%). We implemented gated XUV imaging, filtered diodes and time-integrated x-ray imaging to obtain information about the implosion as well as the stagnation phase for the two cathode geometries. We found that erosion of the knife-edge cathode might be a serious problem, and we had to replace it every 15 shots. On the other hand, the round cathode lasted for the whole series of experiments. We also measured a more reproducible and larger peak current for the knife cathode. From the photo-conductive detectors we observed that even if the round cathode might present shots with higher x-ray yield compared to the knife cathode, dispersion is almost twice as large. Moreover, after a statistic analysis, it is demonstrated that the dispersion in the yield is due solely to differences imposed by the cathodes and not to variations in the driver, as no correlation was found between them. We found that in order to fit the experimental data with the snowplow model, only ∼60% of the total mass is compressed in the knife cathode while ∼20% for the round one, highlighting the importance of the cathode and preionization. Therefore, we conclude that the use of the knife cathode increases the reproducibility of the experiment in comparison with the round cathode.

Projections of wildfire weather danger in the Canary Islands.

Climate change is expected to enhance weather conditions prone to wildfires. Climate regionalized projections for the Canary Islands were performed, using as boundary conditions some of the results provided by the Coupled Model Intercomparison Project (CMIP5) initiative, and covering the recent past (1980-2009) and future (2070-2099) periods, under two Representative Concentration Pathways, 4.5 and 8.5. All fire risk indicators derived from the Canadian Forest Fire Weather Index (FWI) are foreseen to worsen by the end of the century. The fire season could increase its length up to 75 days per year, being more noticeable as altitude increases. The extreme risk days (FWI > 60) show an average increase of 58%, reaching 12 days a year, and the area with high risk could increase by 44%. Analyzing the contribution of the different meteorological variables, it is observed that the main parameter in the fire danger index result is the temperature (currently weights 46%). However, in the future, the importance of precipitation will increase, since the rainfall reduction in some areas could reach 41%. The high dependence of the expected changes on land height, and the small size of the islands, demonstrates the necessity of using high-resolution climate regionalizations.

Herbarium macroalgae specimens reveal a rapid reduction of thallus size and reproductive effort related with climate change.

Understanding and forecasting the effects of climate changes on vulnerable species are leading concerns for ecologists and conservation biologists. Herbaria are invaluable for use in long-term data series, and one of the few available methods for quantifying biodiversity changes over large periods of time. Gelidium canariense is an endemic and habitat-forming macroalga of the Canary Islands that coexists with two other habitat-forming Gelidiales: G. arbuscula and Pterocladiella capillacea. This study assesses long-term changes in thallus size and reproductive effort of all specimens deposited in the Herbarium of Universidad de La Laguna of these three Gelidiales species. Also assessed were the effects of seawater temperature and increased incident light on net primary production (NPP), and the effects of extreme desiccation conditions on the relative water content and NPP of the three Gelidiales species. The length of the thallus of the endemic species G. canariense was halved during the past 40 years. The shortening of the thallus coincided with a significant decrease in the number of reproductive structures in both Gelidium species. These morphological changes coincide with a significant increase of the sea surface temperature, air temperature above sea surface and ultraviolet radiation in the studied area. The experiments have revealed the deleterious effects of extreme desiccation and extreme irradiance on all three species. Hence, these results suggest that air temperature and irradiance are related with these morphological changes over time in the habitat-forming Gelidium species and that are most likely compromising the survival of their populations which are already declining.

The mechanical response of commercially available bone simulants for quasi-static and dynamic loading.

Bone is a complex hierarchal structured material with varying porosity and mechanical properties. In particular, human cranial bone is essentially a natural composite consisting of low porosity outer and inner tables and a cancellous interior, or diploë. Experimental studies of biomechanically accurate cranial bone analogues are of high importance for biomechanical, forensics, and clinical researchers, which could improve the understanding and prevention of traumatic injury. Many reported studies use commercially available bone surrogates to draw biomechanical and forensics conclusions; however, their mechanical properties are not tabulated over a range of strain rates. This study elucidates the mechanical viability of three leading commercially available bone surrogates, i.e. Synbone, Sawbone, and Bonesim, over a large range of strain rates (10-3 to 103 s-1). Quasi-static compression testing was conducted using a universal testing machine and a Split-Hopkinson Pressure bar system equipped with high-speed video was used to determine the dynamic mechanical behavior of these materials. Micro-computed X-ray tomography (XRT) were performed on each material to investigate their pore structures and distributions. All materials exhibited strain rate dependent strength behavior, particularly at high loading rates (≥103 s-1). The Young's modulus was found to increase with strain rate from 10-3 to 10-1 s-1 for transversely and longitudinally loaded surrogate materials except for Synbone and the higher density Bonesim. The higher density Bonesim was determined to be the most suitable cranial bone simulant tested based on a combination of transverse Young's Modulus (1500 MPa), yield strength (19 MPa), ultimate strength (49 MPa), and ultimate strain (17%). These materials show limited promise for applications where the measured elastic properties and strengths are of interest.

Urodynamic study in women with pure stress urinary incontinence.

OBJECTIVE: To describe the results of urodynamic study in women with pure stress urinary incontinence symptoms, including the characteristics of the overactive detrusor. No other clinical assessments were taken into account. MATERIAL AND METHODS: A retrospective study in women with urinary incontinence consecutively evaluated by urodynamic study. From a total of 710 women, only 108 (15%) with pure stress urinary incontinence symptoms were selected. Women with prior urinary incontinence surgery, pelvic organ prolapse (stage ≥iii), pelvic radiotherapy, using medication active on the lower urinary tract and neurological diseases were excluded. Infusion rate was 70 ml/min. Detrusor overactivity was induced only by cough. A standardized cough stress test with progressive cough intensity was carried out. RESULTS: Reference urodynamic values for stress incontinent women are described. Urodynamic stress incontinence was observed in 79 women (73.1%), detrusor overactivity in 4 (3.7%) and mixed urodynamic diagnosis in 15 (13.8%). Test was inconclusive in 10 patients (9.2%). Two women had detrusor overactivity incontinence (1.9%). One patient had detrusor overactivity induced by cough without urodynamic stress incontinence (0.9%). There was an association between detrusor overactivity and nocturia ≥2 (P=.002; odds ratio: 3.74; 95% confidence interval: 1.22-11.39). One woman had a bladder outlet obstruction (0.9%). CONCLUSIONS: In women with pure stress urinary incontinence, without knowing the outcome of other clinical assessments, urodynamic study can provide useful information to define the proper therapy.

Corrección de «labio ondulado» en elsíndrome de Melkersson-Rosenthal / Upper lip «ruffle deformity» correction in Melkerson-Rosenthal’s syndrome

El Síndrome de Melkersson-Rosenthal es una entidad rara caracterizada por edema granulomatoso oro facial, episodios de parálisis facial y lengua plegada. La presentación monosintomática de labios se denomina queilitis granulomatosa de Miescher. Clásicamente se ha tratado con múltiples medicamentos con respuesta parcial o insatisfactoria, por lo que el tratamiento ideal es el quirúrgico, que obtiene resultados permanentes y permite al paciente relaciones interpersonales satisfactorias. Sin embargo la corrección propuesta por los diferentes autores disminuye el grosor del labio a expensas de dejar un estigma de deformidad de labio “ondulado” ya que no se acorta el labio en sentido transverso y únicamente se adelgaza. El presente artículo describe el tratamiento propuesto para corregir esta deformidad mediante la resección en bloque del tercio medio del labio superior. Además hace referencia a la afectación del cuello en el caso que presentamos, no descrita en la bibliografía actual al respecto, que daba al paciente un aspecto de cuello de “iguana”, y que fue corregida mediante resección en huso y liposucción (AU)

Melkersson-Rosenthal Syndrome is a rare entity characterized by granulomatous orofacial swelling, recurrent facial palsy and lingua plicata. It’s monosyntomatic form affecting only lips is known as Miescher (..) (AU)

Small cell neuroendocrine carcinoma of the cervix: Analysis of outcome, recurrence pattern and the impact of platinum-based combination chemotherapy.

OBJECTIVES: To analyze progression-free (PFS) and overall survival (OS) in patients with small cell neuroendocrine carcinoma of the cervix (SCNEC), and to determine whether platinum-based combination chemotherapy is beneficial for this population. METHODS: We performed a retrospective analysis of all patients with SCNEC who were treated at our institution between 1/1990 and 2/2007. Patients were excluded if pathologic diagnosis was not confirmed at our institution. Standard statistical methods were utilized. RESULTS: Seventeen patients met inclusion criteria. The estimated 3-year PFS and OS rates for the entire group were 22% and 30%, respectively. Median time to progression was 9.1 months. Extent of disease was the only significant prognostic factor. Median OS for patients with early stage disease (IA1-IB2) was 31.2 months and 6.4 months for patients with advanced stage disease (IIB-IV, P=0.034). In the early-stage disease group, the 3-year distant recurrence-free survival rate was 83% for patients who received chemotherapy and 0% for patients who did not receive chemotherapy as part of their initial treatment (P=0.025). The estimated 3-year OS rate was 83% for patients who received and 20% for patients who did not receive chemotherapy as part of their initial treatment (P=0.36). CONCLUSION: Given the rarity of SCNEC this retrospective analysis is limited by a small number of patients. However, the natural history of this rare disease is akin to small cell lung cancer and the prognosis is poor due to the tumor's propensity for distant spread. The treatment should conform to the treatment of small cell lung cancer.

[Study of the introduction of the European Credit Transfer System (ECTS) in pediatrics and modification of the teaching methodology]. / Estudio sobre la introducción del Sistema de Transferencia de Créditos Europeo en Pediatría y modificaciones de la metodología docente.

INTRODUCTION: Spanish medical faculties have initiated the new curriculum reform process within the framework of the European Higher Education Area and are required to incorporate the European Credit Transfer System (ECTS) to new syllabi before 2010. OBJECTIVES: To test the introduction of the ECTS in pediatrics and modify the teaching methodology. STUDY DESIGN: The theoretical and practical programs were adapted; academic objectives and a student evaluation system were established. Students were surveyed on starting the second term of the 2004-05 academic year before the theory examination and again on terminating the academic year: a 5-point Likert-type scale was used for responses. Priorities for generic and specific competencies selected by students were compared with those selected by the National Deans Conference (NDC). The results were analyzed using non-parametric tests. RESULTS: Fifteen credits became 11 ECTS, with 297 student working hours. The theory program was reduced from 80 to 52 lessons. The students prepared 14 tutor-supervised case presentations. The teaching staff considered that learning of theory was similar to previous years (66 %) and that practical learning improved (73.3 %). The students thought the program should continue (73.2 %) but 98.8 % considered the workload excessive. The students believed that their practical training and their ability to prepare and make case presentations significantly improved during the semester. Academic performance was significantly higher than that in students of the previous year. Students agreed with NDC priorities for 9/9 general and 4/17 specific competencies. Estimation of workload by students was significantly higher than that by staff, and 73.3 % of the students believed that workload should be reduced and the examination system improved. CONCLUSIONS: Introducing the ECTS improved academic performance, practical training, and self-directed learning. The project was satisfactory for staff and students. Student workload was underestimated.

Estudio sobre la introducción del Sistema de Transferencia de Créditos Europeo en Pediatría y modificaciones de la metodología docente / Study of the introduction of the european credit transfer system (ECTS) in pediatrics and modification of the teaching methodology

Introducción Las Facultades Médicas españolas han comenzado el nuevo proceso de reforma curricular en el marco del proceso de implantación del Espacio Europeo de Educación Superior y deben incorporar el Sistema de Transferencia de Créditos Europeo (ECTS) a los nuevos planes del estudio antes de 2010. Objetivos El objetivo del trabajo fue experimentar la introducción de los créditos ECTS en la asignatura de Pediatría y modificar la metodología docente. Diseño del estudio Adaptación del programa teórico y práctico, estableciendo unos objetivos docentes y un sistema de evaluación. Se realizaron encuestas a los alumnos al inicio del segundo cuatrimestre del curso 2004-2005, antes de realizar el examen teórico de la asignatura y al finalizar el curso académico, utilizando para las respuestas una escala de tipo Likert con 5 grados. Se comparó la priorización de las competencias genéricas y específicas de los alumnos con la de los profesionales médicos en la encuesta de la Conferencia Nacional de Decanos (CND). Para el análisis de los resultados se aplicaron pruebas no paramétricas. Resultados Los 15 créditos actuales se transformaron en 11 ECTS, con 297 h de trabajo para los alumnos. Se redujo el programa teórico de 80 a 52 lecciones. Los alumnos prepararon y presentaron 14 casos clínicos, bajo la supervisión de sus tutores. Los profesores consideraron que el aprendizaje teórico había sido similar al de cursos anteriores (66,6 %) y había sido mejor el práctico (73,3 %). Los alumnos opinaron que el proyecto debía continuar (73,2 %), pero el 98,8 % consideraron que la carga de trabajo había sido excesiva. Los alumnos apreciaron de forma estadísticamente significativa que mejoró la docencia práctica y su capacidad para preparar y presentar casos clínicos. El rendimiento académico de los alumnos fue significativamente mejor que el de los alumnos del curso anterior. Los estudiantes estuvieron de acuerdo con la prioridad de competencias de la CND para 9/9 de las generales y 4/17 de las específicas. La estimación de horas de trabajo de los alumnos fue mayor por los alumnos que por los profesores. El 73,3 % de los alumnos contestaron que el proyecto debía mejorarse, reduciendo la carga de trabajo de los alumnos y mejorando el sistema de evaluación. Conclusiones La introducción de los ECTS mejoró el rendimiento académico, la formación práctica y el autoaprendizaje de los alumnos. La experiencia fue satisfactoria para profesores y alumnos. La estimación de la carga de trabajo de los alumnos fue subestimada

Introduction Spanish medical faculties have initiated the new curriculum reform process within the framework of the European Higher Education Area and are required to incorporate the European Credit Transfer System (ECTS) to new syllabi before 2010. Objectives To test the introduction of the ECTS in pediatrics and modify the teaching methodology. Study design The theoretical and practical programs were adapted; academic objectives and a student evaluation system were established. Students were surveyed on starting the second term of the 2004-05 academic year before the theory examination and again on terminating the academic year: a 5-point Likert-type scale was used for responses. Priorities for generic and specific competencies selected by students were compared with those selected by the National Deans Conference (NDC). The results were analyzed using non-parametric tests. Results Fifteen credits became 11 ECTS, with 297 student working hours. The theory program was reduced from 80 to 52 lessons. The students prepared 14 tutor-supervised case presentations. The teaching staff considered that learning of theory was similar to previous years (66 %) and that practical learning improved (73.3 %). The students thought the program should continue (73.2 %) but 98.8 % considered the workload excessive. The students believed that their practical training and their ability to prepare and make case presentations significantly improved during the semester. Academic performance was significantly higher than that in students of the previous year. Students agreed with NDC priorities for 9/9 general and 4/17 specific competencies. Estimation of workload by students was significantly higher than that by staff, and 73.3 % of the students believed that workload should be reduced and the examination system improved. Conclusions Introducing the ECTS improved academic performance, practical training, and self-directed learning. The project was satisfactory for staff and students. Student workload was underestimated

[Spontaneous intracranial hypotension: the value of isotope cisternoscintigraphy using 99mTc-DTPA]. / Síndrome de hipotensión intracraneal espontánea: utilidad de la cisternogammagrafía isotópica con 99mTc-DTPA.

INTRODUCTION: Spontaneous intracranial hypotension (SIH) is an infrequent clinical entity that is found predominantly in young adults and is characterised by the presence of acute or subacute headaches that appear on standing up and subsides on lying down. CASE REPORT: A 35-year-old female with a three-month history of holocranial headaches, accompanied by dizziness and gait instability, which increase on standing up and diminish to a certain extent on lying down, associated to bilateral tinnitus. The patient's history included a slight strain made 4 months earlier, with a sudden non-irradiated pain in the back of the neck that got better spontaneously. On the basis of the clinical and radiological findings from an MRI scan of the head and neck, our service was asked to perform a cisternoscintigraphy. CONCLUSIONS: Isotope cisternoscintigraphy using 99mTc-DTPA confirmed the diagnosis of the process and enabled us to locate the CSF leak. We therefore think it advisable to highlight its value in the diagnosis of SIH syndrome so as to be able to avoid the use of other invasive complementary explorations that entail a certain degree of morbidity and mortality.

[Food habits and dietary intake during the first year of life]. / Hábitos alimentarios e ingesta dietética en el primer año de vida.

OBJECTIVE: To determine feeding habits and dietetic ingestion du-ring the first year of life and to assess whether these are in accordance with dietetic recommendations. PATIENTS AND METHODS: A total of 171 healthy infants between 1 and 12 months old were studied. Two types of inquiry were carried out: 24-recall and weekly frequency of food. RESULTS: The percentage and duration of breastfeeding was low. Feeding with cows milk was more frequent than with breast milk from the age of 3 months. Thirty-eight per-cent of children had whole cows milk from the age of 6 months. Complementary feeding was introduced in accordance with international recommendations. The ingestion of energy and nutrients was also in accordance with the recommendations of the RDA during the first 6 months of life. In children aged 6-12 months, energy in-take was sufficient but diets were high in proteins and II-pIns and fairly high in carbohydrates. CONCLUSION: Ingestion of micronutrients and minerals are higher than is recommended except in the case of zinc.

Hábitos alimentarios e ingesta dietética en el primer año de vida / Dietetic ingestion and feeding habits during the first year of life

Scanear (AU)

Insulin during the early postembryonic development of the gilt-head sea bream, Sparus aurata: ultrastructural, immunohistochemical, and biochemical studies.

Insulin was sought during the early postembryonic development of gilt-head sea bream, Sparus aurata, using ultrastructural, immunohistochemical and biochemical techniques. The endocrine pancreas appeared at hatching (Day 0) as a single cluster of morphologically similar cells. Secretory granules formed from Day 1 onwards but the cells could only be identified as insulin-producing B cells at the end of the endotrophic period (Day 3-Day 4). Insulin-immunoreactive cells were detected in the pancreatic primordium from hatching onwards and their number increased after the end of the endo-exotrophic period. Early insulin production was also found using an ELISA method on homogenates of prelarvae and larvae. Insulin levels were fairly high during the endotrophic period, decreased strongly at mouth opening, and then increased at the end of the endo-exocrine period. The origin and role of the large amount of hormone detected during the strictly endotrophic phase of ontogenesis are discussed in light of data on other vertebrates.

Determination of selenium levels in dairy products and drinks by hydride generation atomic absorption spectrometry: correlation with daily dietary intake.

The selenium concentrations in different dairy products and drinks in the Mediterranean coastal area of southeastern Spain have been determined by hydride generation atomic absorption spectrometry. Mineralization was carried out with an HNO3-HClO4 mixture (4:1) in a thermostatted sand bath. Selenium determination was carried out by the standard addition method. Mean concentrations obtained in diary products varied from 6.87 ng/g (rice pudding) to 178.90 ng/g (caramel custard), and those in drinks from 0.256 micrograms/l (wine) to 2.879 micrograms/l (pineapple juice). Repeatability, expressed as relative standard deviation, ranged from 5.06% to 13.25%. The results obtained from the recovery studies were proximate to 100%. Considering the mean daily individual consumption of these foods in Andalusia (southern Spain), the daily dietary intake of selenium supplied by this source is 5.869 micrograms per person per day.

Maturation of the endocrine pancreas in the sea bass, Dicentrarchus labrax L. (Teleostei): an immunocytochemical and ultrastructural study. I. Glucagon-producing cells.

The structure of the endocrine pancreas in the sea bass (Dicentrarchus labrax L.) was studied with special reference to glucagon-immunoreactive cells. As described in most of the teleosts, the sea bass was found to have a diffuse pancreas. In the adult, endocrine cells were clustered in a principal islet and numerous accessory islets where the glucagon A cells were localized peripherally. Under electron microscopy, the A cells displayed a clear hyaloplasm with granules having typical spherical or polyhedral cores, as in other vertebrates. The maturation of the endocrine pancreas was monitored under rearing conditions. The endocrine pancreas appeared during the prelarval stage, 3 days after hatching, and consisted of a single cluster of morphologically similar cells, containing very small cytoplasmic granules. During the larval stage, cytodifferentiation resulted in modifications of cell shape and increased granule size. Typical granules appeared in 8-mm-long larvae. Cells immunoreactive with mammalian glucagon antibodies appeared only at the beginning of the juvenile stage (3 months/20 mm). Electron microscope observations revealed that the storage of hormone in numerous cytoplasmic granules began at this stage.

[Comparison of the levels of serum ferritin and other hematologic parameters in males and pre-menarche and post-menarche females]. / Comparación de los niveles de ferritina sérica y otros parámetros hematológicos en varones y hembras premenárquicas y postmenárquicas.

Our study group consisted of 43 healthy preadolescence and adolescence of which 17 were boys and 13 premenarcheal and 13 postmenarcheal girls. Haematocrit, haemoglobin, serum iron, transferrin saturation, total iron-binding capacity, latent iron-binding capacity and serum ferritin were analyzed. Authors found that post-menarcheal girls are at lower levels than boys and that menstrual blood loss is a significant factor in determining iron status.

[HLA haplotypes in congenital adrenal hyperplasia (21-hydroxylase deficiency]. / Haplotipos HLA en la hiperplasia suprarrenal congénita (deficiencia de 21-hidroxilasa).

In order to study HLA haplotypes in congenital adrenal hyperplasia secondary to 21 hydroxylase (21-OH) deficiency, HLA typing was performed in Three families with six affected members. HLA genotypes revealed that in family number 1, two of the three affected members with CAH 21-OH presented salt-losing syndrome and were genotypically identical for HLA A1, B15/A32, Bw35. Family number 2 had two affected members with CAH 21-OH and salt-losing and they were genotypically identical for HLA A11, Bw51/A29, B12. In family number 3, only one of three members presented CAH 21-OH without salt-losing and was HLA homozygous A29, B12/A29, B12; the other two family members were heterozygous with genotype HLA A2, B37/A29, B12. The study suggests that haplotype HLA A29, B12 is related to CAH 21-OH with or without salt-losing syndrome.