Producción y valor nutritivo de la mezcla de seis gramíneas y dos leguminosas bajo condiciones de pastoreo.

Se determinó la producción de materia seca, el porcentaje de utilización y el valor nutritivo de 6 gramíneas sembradas solas y fertilizadas (50 kg de N/ha/pastoreo) y en mezcla con 2 variedades de trébol violeta, en un suelo salino. Las producciones de materia seca variaron en los 4 pastoreos, tanto para las mezclas con tréboles como para las gramíneas fertilizadas, las cuales fueron superiores a las producciones en época de invierno, mientras que las mezcladas con los tréboles Levezon y Triel presentaron: 0.70; 0.49 y 0.48 ton/ha/pastoreo respectivamente. Las mezclas más estables a través de los pastoreos, fueron las realizadas con los raigrases: manawa e italiano y se obtuvieron producciones de materia seca en mezclas equivalentes a una fertilización con 35 kg N/ha/pastoreo. El porcentaje de utilización de gramíneas fertilizadas con N poco varió entre épocas, tuvo un promedio de 88.4 por ciento, mientras las mezclas con tréboles tuvieron un promedio de 82.55 por ciento, siendo su utilización mayor en época de invierno. Los contenidos promedios de proteína de las gramíneas fueron mayores con la fertilización nitrogenada (20.06 por ciento), que en la mezcla con los tréboles Levezon y Triel (19.94 y 18.88 por ciento respectivamente). Las gramíneas fertilizadas con N tuvieron un contenido promedio de fibra en detergente neutro de 51.31 por ciento y superior al obtenido en las mezclas con tréboles de 41.73 por ciento siendo el contenido de fibra en detergente neutro, mayor en época de veranoPastos y forrajesMaestría en CienciasMaestrí

The iridium double perovskite Sr2YIrO6 revisited: A combined structural and specific heat study

Recently, the iridate double perovskite Sr$_2$YIrO$_6$ has attracted considerable attention due to the report of unexpected magnetism in this Ir$^{5+}$ (5d$^4$) material, in which according to the J$_{eff}$ model, a non-magnetic ground state is expected. However, in recent works on polycrystalline samples of the series Ba$_{2-x}$Sr$_x$YIrO$_6$ no indication of magnetic transitions have been found. We present a structural, magnetic and thermodynamic characterization of Sr$_2$YIrO$_6$ single crystals, with emphasis on the temperature and magnetic field dependence of the specific heat. Here, we demonstrate the clue role of single crystal X-ray diffraction on the structural characterization of the Sr$_2$YIrO$_6$ double perovskite crystals by reporting the detection of a $\sqrt{2}a \times \sqrt{2}a \times 1c$ supercell, where $a$, $b$ and $c$ are the unit cell dimensions of the reported monoclinic subcell. In agreement with the expected non-magnetic ground state of Ir$^{5+}$ (5d$^4$) in Sr$_2$YIrO$_6$, no magnetic transition is observed down to 430~mK. Moreover, our results suggest that the low temperature anomaly observed in the specific heat is not related to the onset of long-range magnetic order. Instead, it is identified as a Schottky anomaly caused by paramagnetic impurities present in the sample, of the order of $n \sim 0.5(2)$ \%. These impurities lead to non-negligible spin correlations, which nonetheless, are not associated with long-range magnetic ordering.Comment: 20 pages, 10 figure

Clinical review: Goal-directed therapy - what is the evidence in surgical patients? The effect on different risk groups

Patients with limited cardiac reserve are less likely to survive and develop more complications following major surgery. By augmenting oxygen delivery index (DO2I) with a combination of intravenous fl uids and inotropes (goaldirected therapy (GDT)), postoperative mortality and morbidity of high-risk patients may be reduced. However, although most studies suggest that GDT may improve outcome in high-risk surgical patients, it is still not widely practiced. We set out to test the hypothesis that GDT results in greatest benefi t in terms of mortality and morbidity in patients with the highest risk of mortality and have undertaken a systematic review of the current literature to see if this is correct. We performed a systematic search of Medline, Embase and CENTRAL databases for randomized controlled trials (RCTs) and reviews of GDT in surgical patients. To minimize heterogeneity we excluded studies involving cardiac, trauma, and paediatric surgery. Extremely high risk, high risk and intermediate risks of mortality were defi ned as >20%, 5 to 20% and <5% mortality rates in the control arms of the trials, respectively. Metaanalyses were performed and Forest plots drawn using RevMan software. Data are presented as odd ratios (OR; 95% confi dence intervals (CI), and P-values). A total of 32 RCTs including 2,808 patients were reviewed. All studies reported mortality. Five studies (including 300 patients) were excluded from assessment of complication rates as the number of patients with complications was not reported. The mortality benefi t of GDT was confi ned to the extremely high-risk group (OR = 0.20, 95% CI 0.09 to 0.41; P < 0.0001). Complication rates were reduced in all subgroups (OR = 0.45, 95% CI 0.34 to 0.60; P < 0.00001). The morbidity benefi t was greatest amongst patients in the extremely high-risk subgroup (OR = 0.27, 95% CI 0.15 to 0.51; P < 0.0001), followed by the intermediate risk subgroup (OR = 0.43, 95% CI 0.27 to 0.67; P = 0.0002), and the high-risk subgroup (OR 0.56, 95% CI 0.36 to 0.89; P = 0.01). Despite heterogeneity in trial quality and design, we found GDT to be beneficial in all high-risk patients undergoing major surgery. The mortality benefit of GDT was confined to the subgroup of patients at extremely high risk of death. The reduction of complication rates was seen across all subgroups of GDT patients

Dilution of the magnetic lattice in the Kitaev candidate α\alpha-RuCl3_3 by Rh3+^{3+} doping

Magnetic dilution of a well-established Kitaev candidate system is realized in the substitutional Ru$_{1-x}$Rh$_x$Cl$_3$ series ($x = 0.02-0.6$). Optimized syntheses protocols yield uniformly-doped single crystals and polycrystalline powders that are isostructural to the parental $\alpha$-RuCl$_3$ as per X-ray diffraction. The Rh content $x$ is accurately determined by the quantitative energy-dispersive X-ray spectroscopy technique with standards. We determine the magnetic phase diagram of Ru$_{1-x}$Rh$_x$Cl$_3$ for in-plane magnetic fields from magnetization and specific-heat measurements as a function of $x$ and stacking periodicity, and identify the suppression of the magnetic order at $x \approx 0.2$ towards a disordered phase, which does not show any clear signature of freezing into a spin glass. Comparing with previous studies on the substitution series Ru$_{1-x}$Ir$_x$Cl$_3$, we propose that chemical pressure would contribute to the suppression of magnetic order especially in Ru$_{1-x}$Ir$_x$Cl$_3$ and that the zigzag magnetic ground state appears to be relatively robust with respect to the dilution of the Kitaev--$\Gamma$--Heisenberg magnetic lattice. We also discovered a slight dependence of the magnetic properties on thermal cycling, which would be due to an incomplete structural transition

Incidencia de microorganismos mesófilos en la producción del agua de bebida envasada

With the purpose, of determining the likely incidence of mesophilic microorganisms on bottled drinking-water (BDW), the most relevant factors involved in the water production were analyzed. In order to determine the quality, water was stored in several different containers (polycarbonate, glass, high-density polyethylene (HDP), low-density polyethylene (LDP), and polyethylene-coextruded polypropilene (PCP) containers), and subsequently total counts were analysed for mesophilic microorganisms and the most likely number for total coliforms and Pseudomona aeruginosa. The best results were achieved by using glass-containers. Subsequently the treatment of water (chlorination-ozonisation) was compared by using two types of containers (LDP and PCP) so as to determine which material and treatment best kept best the organoleptic and physicochemical features, as well as causing the lowest incidence of mesophilic microorganism during the span of product storage. The most adequate container turned out to be that made from 2.5 gauge PCP with 0.6 ppm chlorine treatment It was also concluded that bacterial growth was more an additional by-product of storage and typeof container since our sampling of the production methods showed that at al1 times the water was drinkable. Lastly, a tasting panel was held where 80% of the tasters selected chose the PCP.Con el fin de determinar una posible incidencia de microorganismos mesófilos en la producción del agua de bebida envasada, se analizaron los factores más importantes implicados en la producción. Para determinar la calidad del agua, se almacenó en diferentes tipos de envases (policarbonato, vidrio, polietileno de alta densidad (PAD), polietileno de baja densidad (PBD) y polipropileno coextruído con polietileno (PCP), y posteriormente se realizaron recuentos totales para microorganismos mesófilos y número más probable paracoliformes totales y Pseudomona aeruginosa obteniéndose menores recuentos en el agua envasada  en vidrio. Posteriormente, se compararon los tratamientos de descontaminación del agua (cloraciónozonización) utilizando dos tipos de envase (PBD y PCP), para determinar el material y tratamiento que conservan mejor las características organolépticas-fisicoquimicas y la menor incidencia de microorganismos mesófilos durante el tiempo de almacenamiento del producto. El envase más adecuado es el de PCP de calibre 2,5 con el tratamiento de cloro 0,6 pm; también se demostró que el crecimiento bacteria no fue un producto más del almacenamiento y el tipo de envase, ya que al realizar el muestre0 de los sistemas de producción, el agua fue siempre potable. Finalmente, se realizó un panel de saboreo, obteniéndose una preferencia del 80% de los encuestados, hacia el envase de PCP con el tratamiento de cloro

Influencia del tamaño, la variedad y la proporción de sexos en la producción de huevos de tilapia (Oreochromis spp) en un sistema tropical intensivo al aire libre

The effect of the variety, size of the females and sex ratio in the production of eggs of Chitralada (CH: Oreochromis niloticus) and Taiwanese red (TR: O. mossambicus x O. niloticus) in outdoor concrete tanks were evaluated in a fish production unit located in the Andean foothills of the state of Trujillo, Venezuela. A 2x2x3 factorial arrangement design was used: two varieties (CH and TR), two sizes (large and small) and three female male proportions (1:1, 2:1 and 3:1). CH females produced greater volume and mass of eggs, spawned 2.4-fold more and were more fertile than TR (p&lt;0.01). Large tilapia had 1.6-fold fewer spawning (p&lt;0.05) and produced fewer eggs per 100 females than small ones (p&lt;0.01). In general, the F:M ratio did not affect the reproductive variables. The small females of both varieties had a higher number of spawning than the large ones, and the large CH tilapia spawned 3.9 times more than the TR of the same size (p&lt;0.01), while in the small ones this difference was only 1.7 times (p&lt;0.05). The large CH tilapias were reproductively more efficient than the females of the same category of the TR variety. In conclusion, the CH tilapia and the smaller size and weight females were reproductively more efficient than those of the TR variety and the larger ones. Regardless of the variety, the reproductive activity was not affected by the proportions between females and males.Se evaluó el efecto de la variedad, tamaño de las hembras y relación hembra macho en la producción de huevos de tilapias Chitralada (CH: Oreochromis niloticus) y Taiwanesa roja (TR: O. mossambicus x O. niloticus), en tanques de concreto al aire libre, en una unidad de producción piscícola localizada en el Piedemonte Andino del estado Trujillo, Venezuela. Se utilizó un diseño en arreglo factorial 2x2x3: dos variedades (CH y TR), dos tamaños (grades y pequeñas) y tres proporciones hembra macho (1:1, 2:1 y 3:1). Las hembras CH produjeron mayor volumen y masa de huevos, desovaron 2.4 veces más y fueron más fecundas que las TR (p&lt;0.01). Las tilapias grandes tuvieron 1.6 veces menos desoves (p&lt;0.05) y produjeron menos huevos por cada 100 hembras que las pequeñas (p&lt;0.01). En general, la relación H:M no afectó las variables reproductivas. Las hembras pequeñas de ambas variedades tuvieron un mayor número de desoves que las grandes, y las tilapias CH grandes desovaron 3.9 veces más que las TR del mismo tamaño (p&lt;0.01), mientras que en las pequeñas esta diferencia fue de tan solo 1.7 veces (p&lt;0.05). Las tilapias CH grandes fueron reproductivamente más eficientes que las hembras de la misma categoría de la variedad TR. En conclusión, las tilapias CH y las hembras de menor talla y peso fueron reproductivamente más eficientes que las de la variedad TR y las de mayor tamaño. Independientemente de la variedad, la actividad reproductiva no se vio afectada por las proporciones entre hembras y machos

Iridium double perovskite Sr2YIrO6: A combined structural and specific heat study

© 2017 American Physical Society.Recently, the iridate double perovskite Sr2YIrO6 has attracted considerable attention due to the report of unexpected magnetism in this Ir5+ (5d4) material, in which according to the Jeff model, a nonmagnetic ground state is expected. However, in recent works on polycrystalline samples of the series Ba2-xSrxYIrO6 no indication of magnetic transitions have been found. We present a structural, magnetic, and thermodynamic characterization of Sr2YIrO6 single crystals, with emphasis on the temperature and magnetic field dependence of the specific heat. As determined by x-ray diffraction, the Sr2YIrO6 single crystals have a cubic structure, with space group Fm3m. In agreement with the expected nonmagnetic ground state of Ir5+ (5d4) in Sr2YIrO6, no magnetic transition is observed down to 430 mK. Moreover, our results suggest that the low-temperature anomaly observed in the specific heat is not related to the onset of long-range magnetic order. Instead, it is identified as a Schottky anomaly caused by paramagnetic impurities present in the sample, of the order of n∼0.5(2)%. These impurities lead to non-negligible spin correlations, which nonetheless, are not associated with long-range magnetic ordering

Prevalence of canine visceral leishmaniasis in municipalities of huila, colombia

With the purpose of establishing the prevalence of canine leishmaniasis a descriptive study was carried out in 17 villages of the municipalities of Neiva, Tello and Algeciras, in the department of Huila, Colombia. The selected canine population was composed of 307 dogs, which were submitted to clinical examination, stained smears of lymph node needle aspiration, and bleeding for serological analysis by the Immunofluorescent Antibody Tests (IFAT). The canine population was conformed by mestizo dogs, with a 3 year age average; 30,6 % were females. Upon physical examination loss of weight was observed in 31% of dogs; lynfadenopathy of the popliteal node in 3,2 %; alopecia in 21,8 %, eritematous lesions in 11,5 % and skin ulcers in 3,3 %. 17,2 % of the dogs has a positive serology and in 1.43% of them, amastigotes were observed in the smears of lymph node aspirates. These prevalence of anti-L. chagasi antibodies is relatively high compared with other studies in Colombia and in other countries. The present study, confirms the endemic nature of the illness in the area, high lighting the need for strengthening public health surveillance and active search for human cases.Con el propósito de establecer la prevalencia de leishmaniosis canina se efectuó un estudio descriptivo en 307 caninos, ubicados en 17 veredas de los municipios de Neiva, Tello y Algeciras, a los cuales se les practicó examen clínico, punción y aspiración del ganglio linfático poplíteo para extendido y coloración en lámina; toma de sangre completa por venopunción para análisis mediante la técnica de inmunofluorescencia indirecta. La población canina estuvo conformada por perros mestizos con edad promedio de tres años; el 30,6 % fueron hembras y el 69,4 % machos. En el examen físico de los caninos se observó: enflaquecimiento, 31 %; onicogrifosis, 29,3 %; linfadenitis de ganglio poplíteo 3,2 %; áreas alopécicas 21,8 %; lesiones eritematosas 11,5 % y úlceras cutáneas 3,3 %. El 1,4 % de los caninos analizados presentaron amastigotes en el aspirado y el 17,2 % fueron seropositivos. La prevalencia de anticuerpos contra L. chagasi es alta comparada con otros estudios realizados en Colombia y otros países, corroborando la endemicidad de la enfermedad en el área. Por consiguiente, es necesario fortalecer las estrategias de vigilancia epidemiológica y la búsqueda activa de casos humanos