910 research outputs found
Quick Analysis of Organic Amendments via Portable X-ray Fluorescence Spectrometry
The determination of heavy metals in soils and organic amendments, such as compost, manure, biofertilizer, and sludge, generally involves the digestion of samples with aqua regia, and the determination of those in the solution using various techniques. Portable X-ray fluorescence (PXRF) has many advantages in relation to traditional analytical techniques. However, PXRF determines the total elemental content and, until now, its use for the analysis of organic amendments has been limited. The objective of this work is the calibration of a PXRF instrument to determine the aqua regia-soluble elemental contents directly in solid samples of organic amendments. Our proposal will avoid the digestion step and the use of other laboratory techniques. Using a training set of samples, calibration functions were obtained that allow the determination of the aqua regia-soluble contents from the PXRF readings of total contents. The calibration functions (obtained by multiple linear regression) allowed the quantitative determination of the aqua regia-soluble contents of Fe, K, P, S, Zn, Cu, Pb, Sr, Cr, and Mn, as well as the organic matter content and a semi-quantitative assessment of Al, Ca, V, Ba, Ni, and As contents. The readings of Si, Fe, Al, Ca, K, or S were used as correction factors, indicating that the calibrations functions found are truly based on the chemical composition of the sample matrix. This study will allow a fast, cheap, and reliable field analysis of organic amendments and of other biomass-based materials.Spanish Ministry of Science, Innovation and Universities, and the European Regional Development Fund, European Union, (AEI/FEDER, UE), grant number CGL2016-78937-R
Somatic embryogenesis in explants of adult wild olive trees
In this investigation, somatic embryogenesis in explants of adult wild olive trees, using the protocol developed by Mazri et al. (2013, Sci. Hort. 159: 88-95), was induced. Four genotypes differring in the level of resistance to the fungal pathogen Verticillium dahliae were used: Ac18, StopVert and OutVert (symptomless resistant genotypes, Jiménez-Fernández et al. 2015, Plant Pathology, in press) and Ac15 (susceptible genotype, Jiménez-Díaz, IAS-CSIC, Córdoba, personal communication). Three types of explants from actively growing cultures were used: first pair of leaves, petioles and shoot apex. Firstly, all explants were cultured on a liquid induction medium with MS mineral elements at 0.5X and 30 μM TDZ-0.5 μM NAA, for 4 days at 80rpm. Afterwards, explants were transferred to basal MS with 0.5X macroelements, for 8 weeks. Finally, calli were cultured on expression ECO medium supplemented with 0.25 μM IBA, 0.5 μM 2ip and 0.44 μM BA, for several subcultures. Cultures were incubated under darkness at 25 degrees. Embryogenic calli were observed on shoot apex (StopVert) or leaf primordia (Ac18) explants.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Luxación posterior bilateral de la articulación escapulohumeral
Se presenta un caso de un hombre de 51 años, que tras sufrir una crisis convulsiva
presentó dolor e impotencia funcional en ambos hombros. Tras realizar estudio radiográ-
fico y TAC, se comprobó la existencia de una luxación escapulohumeral bilateral. El paciente
fue tratado con reducción cerrada e inmovilización del miembro en abducción y rotación externa
con un yeso toracobraquial.A case of bilateral posterior dislocation of the scapulo-humeral joint ocurring
in a 51-year-old men after a convulsive attack is reported. Inmediately after convulsions, the
patient refered pain and funtional disability in both shoulders and bilateral scapulo-humeral
dislocation was confirmed by conventional radiograhips and CT-scan. Treatment consisted of
closed reduction and inmobilization of the upper extremity in abduction and external rotation
with a thoraco-braquial plaster cast
Glucocerebrosidase mutations and synucleinopathies. Potential role of sterylglucosides and relevance of studying both GBA1 and GBA2 genes.
Gaucher's disease (GD) is the most prevalent lysosomal storage disorder. GD is caused by homozygous mutations of the GBA1 gene, which codes for beta-glucocerebrosidase (GCase). Although GD primarily affects peripheral tissues, the presence of neurological symptoms has been reported in several GD subtypes. GBA1 mutations have recently deserved increased attention upon the demonstration that both homo- and heterozygous GBA1 mutations represent the most important genetic risk factor for the appearance of synucleinopathies like Parkinson's disease (PD) and dementia with Lewy bodies (LBD). Although reduced GCase activity leads to alpha-synuclein aggregation, the mechanisms sustaining a role for GCase in alpha-synuclein homeostasis still remain largely unknown. Furthermore, the role to be played by impairment in the physiological function of endoplasmic reticulum, mitochondria and other subcellular membranous components is currently under investigation. Here we focus on the impact of GCase loss-of-function that impact on the levels of sterylglucosides, molecules that are known to trigger a PD-related synucleinopathy upon administration in rats. Moreover, the concurrence of another gene also coding for an enzyme with GCase activity (GBA2 gene) should also be taken into consideration, bearing in mind that in addition to a hydrolytic function, both GCases also share transglycosylation as a second catalytic activity. Accordingly, sterylglycoside levels should also be considered to further assess their impact on the neurodegenerative process. In this regard¿and besides GBA1 genotyping¿we suggest that screening for GBA2 mutations should be considered, together with analytical measurements of cholesterol glycosides in body fluids, as biomarkers for both PD risk and disease progression
Odontoameloblastoma: descripción de un caso y revisión de la literatura
El odontoameloblastoma (OA) es un tumor odontogénico mixto
extremadamente raro que aparece en los huesos maxilares y
que presenta tanto componentes epiteliales como
mesenquimales. El término odontoameloblastoma fue incluido
en la clasificación de 1971 de la OMS. Tan solo 23 casos bien
documentados han sido publicados. Debido a su rareza, existe
controversia en cuanto al tratamiento de este tumor. Presentamos
un nuevo caso de OA que afecta a la mandíbula y simula
un odontoma compuesto, así como una breve revisión de la
literatura.Odontoameloblastoma (OA) is an extremely rare mixed
odontogenic tumor appearing within the maxillary bone, with
both epithelial and mesenchymal components. The term
odontoameloblastoma (OA) was included in the 1971's WHO
classification. Only 23 well-documented cases have been
reported in the medical literature. Because of their rarity,
controversy exists in the treatment of this tumor. We present a
new case of OA involving the mandible mimicking a compound
odontoma and a brief review of the related literature
Quantum corrections to the string Bethe ansatz
One-loop corrections to the energy of semiclassical rotating strings contain
both analytic and non-analytic terms in the 't Hooft coupling. Analytic
contributions agree with the prediction from the string Bethe ansatz based on
the classical S-matrix, but in order to include non-analytic contributions
quantum corrections are required. We find a general expression for the first
quantum correction to the string Bethe ansatz.Comment: 12 pages. Latex. v2: Misprints corrected and references adde
A Survey on Quality of Service in the Voice Over IP Technology
Voice services can be transmitted by circuit switched and packet switched networks (Internet). Voice over Internet Protocol (VoIP) is one of the most attractive and important service in telecommunication networks, current implementations of VoIP have two main types of architectures, which are based on H.323 and Session Initiation Protocol (SIP). However, when the voice traffic is transported over Internet, the packet based transmission may introduce impairments and it has influence on the Quality of Service (QoS) perceived by the end users. The voice quality of VoIP systems depends on many QoS parameters. Particularly, One Way Delay (OWD), jitter and Packet Loss Rate (PLR) have an important impact on voice quality. This survey presents the main concepts relating to the VoIP technology and quality of service issues
Thermal Diffusion and Specular Reflection, Monte Carlo-based Study on Human Skin via Pulsed Fiber Laser Energy
The aim of traditional Chinese medicine (TCM) in acupuncture is sometimes to restore and regulate energy balance by stimulating specific points along the specific meridians traced on the human body via different techniques such as mechanical pressure, moxibustion and others. Hence, physicians have struggled to improve treatment for common diseases such as migraine and headaches. Heat stimulation and some pharmacological effects from moxa have been attributed to the therapeutic efficacy of such techniques. As heat can diffuse through the tissue, skins temperature will rise in the surrounding tissue. In this work, heat diffusion on a simple, 5-layer model of human skin is presented. Based on this, and by using Monte Carlo techniques, a photon or a photon package is launched into the tissue for mimicking the propagation of such photons at two different wavelengths through the tissue. The method generally describes the scholastic nature of radiation interactions. Most of the laser energy is deposited within a volume which cross-sectional area is the size of the beam itself. As could be seen, in the epidermis layer of the model, the heat does not go deep and nearly all the heat diffusion occurs on the edges of the beam, causing losses. Heat dissipation occurs faster and goes down to 2°C in the adipose tissue since there is low water content in this region. On the contrary, there is a fast heat increase in the muscle layer, up to 6°C at the most superficial layer. Since melanin is the most important epidermal chromophore, it can be noted that light shows strong absorption via melanin, at 690nm laser wavelength. In the papillary dermis the heat decreases and spreads out to the surrounding tissue. Once it reaches the adipose tissue, the heat is not absorbed enough; therefore, it is transmitted into the muscle, where the temperature rise is higher and reaches nearly 40 °C. Finally, photodynamics in a simple 5-layer skin model were explored at two laser wavelengths: 690nm and 1069nm, where no thermal damage would be expected, given the energy level of the employed pulses. Such pulsed laser energy levels remain to be tested in living tissue
Retos y nuevas perspectivas en la revegetación de sistemas forestales
Entre los días 21 y 23 de noviembre de 2007 tuvo lugar la I Reunión del Grupo de Trabajo de Repoblaciones Forestales de la Sociedad Española de Ciencias Forestales (SECF) y el grupo de trabajo de Restauración Ecológica de la Asociación Española de Ecología Terrestre, y IV Reunión del Grupo de Trabajo de Repoblaciones Forestales de la SECF en las instalaciones del Rectorado de la Universidad de Alcalá. A la reunión asistieron 74 participantes, y se presentaron un total de 39 comunicaciones orales, 18 paneles y 8 ponencias invitadas. Además, se presentó el libro “Calidad de Planta Forestal para la Restauración en Ambientes Mediterráneos” y se organizaron dos mesas redondas, una sobre “Necesidades reales de investigación en calidad de planta y cultivo de planta forestal en vivero” (Tabla 1) y otra sobre “Necesidades reales de la investigación en reforestación” (Tabla 2, 3). Una densa agenda para alcanzar los principales objetivos de la reunión, la presentación de investigación de calidad en el ámbito de la revegetación de sistemas forestales, y el intercambio de experiencias e inquietudes entre los diversos colectivos implicados en la misma. Pero ¿qué imagen podemos extraer del estado actual de nuestros conocimientos en esta área a partir de las comunicaciones presentadas
Does desmopressin acetate reduce blood loss after surgery in patients on cardiopulmonary bypass?
It has been suggested that desmopressin acetate (DDAVP) administration reduces blood loss after cardiac surgery. We have investigated the effect of DDAVP administration in a double-blind, randomized, prospective trial including 100 patients placed on cardiopulmonary bypass during surgery. Fifty patients received 0.3 micrograms/kg DDAVP and 50 patients received a placebo administered in a 50 ml saline solution over 15 min when cardiopulmonary bypass had been concluded. Results showed no significant differences either in total blood loss per square meter (458 +/- 206 ml in the DDAVP group vs 536 +/- 304 ml in the placebo group) or in necessity for red cell transfusions (1642 +/- 705 ml in the DDAVP group vs 1574 +/- 645 ml in the placebo group) in the first 72 hr after surgery. Only intraoperative blood loss per square meter was significantly lower (p less than .02) in the DDAVP group (131 +/- 106 ml) as compared with the placebo group (193 +/- 137 ml). The prolongation of bleeding time and the decrease of factor VIII:C and factor VIII:von Willebrand factor 90 min after treatment were significantly lower (p less than .001) in the DDAVP group as compared with the placebo group. We conclude that the administration of DDAVP in patients placed on cardiopulmonary bypass during surgery does not reduce total blood loss and is only effective in reducing intraoperative bleeding
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