This study aimed to determine the performance of the averaged parasympathetic tone activity (PTAm) and its dynamic variation (ΔPTA) to assess intraoperative nociception in relation to heart rate (HR) ...and direct mean arterial pressure (MAP) in dogs undergoing laparoscopic ovariectomy. This prospective, observational, clinical study included 32 bitches. The PTAm, HR, MAP, and bispectral index (BIS) were assessed before (pre-stimulus), as well as 1 min and 2 min after, four surgical stimuli: insufflation, introduction of trocars, and removal of the left and right ovaries. A two-way ANOVA was performed to compare PTAm, HR, MAP, and BIS data across surgical stimuli. A ≥ 20% drop in PTAm or a ≥ 20% increase in HR and/or MAP regarding the pre-stimulus values was considered a PTAm-drop and/or a hemodynamic response, respectively. The performance of PTAm pre-stimulus, PTAm 1 min, and ΔPTA in predicting the hemodynamic response was assessed by calculation of the area under the receiver operating characteristic (ROC) curve. At insufflation, PTAm decreased after 1 (p = 0.010) and 2 (p = 0.045)min, and ΔPTA was different (p = 0.005) between dogs that presented hemodynamic response and dogs that did not. At PTAm-drop, MAP increased after 1 min (p = 0.001) and 2 min (p = 0.001) with respect to pre-stimulus value, whereas HR and BIS did not change. ROC curves showed a threshold value of PTAm pre-stimulus ≤51 to detect hemodynamic response (sensitivity 69%, specificity 52%). The PTAm and ΔPTA only assessed intraoperative nociception during insufflation. The PTAm pre-stimulus association to the hemodynamic response in anaesthetized dogs showed poor sensitivity and no specificity.
Context.
Void galaxies are essential for understanding the physical processes that drive galaxy evolution because they are less affected by external factors than galaxies in denser environments, that ...is, in filaments, walls, and clusters. The stellar metallicity of a galaxy traces the accumulated fossil record of the star formation through the entire life of the galaxy. A comparison of the stellar metallicity of galaxies in various environments, including voids, filaments, walls, and clusters can provide valuable insights into how the large-scale environment affects the chemical evolution of the galaxy.
Aims.
We present the first comparison of the relation of the total stellar mass versus central stellar metallicity between galaxies in voids, filaments, walls, and clusters with different star formation history (SFH) types, morphologies, and colours for stellar masses between 10
8.0
to 10
11.5
solar masses and redshift 0.01 <
z
< 0.05. We aim to better understand how the large-scale structure affects galaxy evolution by studying the stellar mass-metallicity relation of thousands of galaxies, which allows us to make a statistically sound comparison between galaxies in voids, filaments, walls, and clusters.
Methods.
We applied non-parametric full spectral fitting techniques (pPXF and STECKMAP) to 10 807 spectra from the SDSS-DR7 (987 in voids, 6463 in filaments and walls, and 3357 in clusters) and derived their central mass-weighted average stellar metallicity (M/H
M
).
Results.
We find that galaxies in voids have slightly lower stellar metallicities on average than galaxies in filaments and walls (by ∼0.1 dex), and they are much lower than those of galaxies in clusters (by ∼0.4 dex). These differences are more significant for low-mass (∼10
9.25
M
⊙
) than for high-mass galaxies, for long-timescale SFH (extended along time) galaxies than for short-timescale SFHs (concentrated at early times) galaxies, for spiral than for elliptical galaxies, and for blue than for red galaxies.
Objetivo: Caracterizar la dinámica de crecimiento de machos de ceba en pastoreo racional Voisin en suelos de topografía ondulada a quebrada, en el trópico húmedo de Los Santos, Panamá. Materiales y ...Métodos: El ensayo se desarrolló en un área de producción de 8,40 ha, dividida en 24 cuartones de 0,35 ha como promedio. Los pastos se manejaron según los principios y conceptos del pastoreo racional Voisin. Se utilizaron 53 novillos, con base Cebú y sus cruces F1 y F2 (Cebú x Holstein), divididos en dos grupos de ceba. El primer período de ceba (27 animales) duró 150 días, y 79 el segundo (26 animales). Los pesos iniciales fueron de 369 y 401 kg, para el primero y segundo grupo, respectivamente. Los pesajes para determinar el incremento de peso vivo por período y la ganancia diaria individual, se realizaron cada 30 días. Los datos se procesaron mediante un análisis de varianza y se usó la dócima de Duncan para p < 0,05. Resultados: La presión de pastoreo fue alta (4,63 kg de MS/100 kg PV/día), con una disponibilidad de pastos promedio de 23,2 kg de MS/a/día. Los animales del primer ciclo de ceba promediaron 0,653 kg/día, con una producción de carne por hectárea de 336,63 kg. En el segundo ciclo, ganaron 0,670 kg diarios, mientras que la producción de carne fue de 145,55 kg/ha. Los dos períodos continuos de ceba permitieron al productor vender más de 24 t de carne en pie en un año. Conclusiones: Es factible la ceba de toros Cebú y sus cruces F1 y F2 en sistema de pastoreo racional Voisin, ya que se obtienen ganancias promedio cercanas a los 0,700 kg/animal/día, sin pérdidas de peso en los momentos de mayor escasez de alimentos. Palabras clave: bovidae, ganancia de peso, manejo de praderas Objective: To characterize the growth dynamics of fattening males under rational Voisin grazing conditions on soils with undulated to rough topography, in the humid tropics of Los Santos, Panama. Materials and Methods: The trial was conducted in a production area of 8,40 ha, divided into 24 paddocks of 0,35 ha as average. The pastures were managed according to the principles and concepts of rational Voisin grazing. Fifty-three steers were used, with Zebu basis and its F1 and F2 crossings (Zebu x Holstein), divided into two fattening groups. The first fattening period (27 animals) lasted 150 days, and the second (26 animals), 79 days. The initial weights were 369 and 401 kg, for the first and second group, respectively. The animals were weighed every 30 days to determine live weight gain per period and individual daily gain. The data were processed by variance analysis and Duncans test was used for p < 0,05. Results: The grazing pressure was high (4,63 kg DM/100 kg LW/day), with an average pasture availability of 23,2 kg DM/a/day. The animals of the first fattening cycle averaged 0,653 kg/day, with a beef production per hectare of 336,63 kg. In the second cycle, they gained 0,670 kg per day; while beef production was 145,55 kg/ha. The two continuous fattening periods allowed the farmer to sell more than 24 t of live beef in one year. Conclusions: It is concluded that the fattening of Zebu bulls and its F1 and F2 crossings in a Voisin rational grazing system is feasible, because average gains close to 0,700 kg/animal/day are obtained, without weight loss at times of higher food shortage. Keywords: bovidae, weight gain, pastureland management
Objetivo; Caracterizar el comportamiento agronómico y la composición química de especies mejoradas en un sistema de pastoreo racional Voisin, en el trópico húmedo de Los Santos, Panamá. Materiales y ...Métodos; Se evaluó el rendimiento y el valor nutricional de un grupo de especies mejoradas, con 24 cuartones y 1,9 días de ocupación promedio. El sistema se pastoreó con 53 novillos de base Cebú y sus cruces F1 y F2 (Cebú x Holstein). Se midieron como indicadores principales: producción de forraje total (kg de MS/ha/rotación), oferta de forraje por especie y porcentajes de MS, PB, FDA, FDN, DIVMS.sub.30, EM, Cenizas, Ca y P. Los datos se procesaron mediante análisis de varianza de clasificación simple. Se utilizó el paquete estadístico IBMR SPSSR Statistics versión 22. Resultados; La producción de forraje varió entre 3 344 y 4 442 kg de MS/ha/rotación. El mayor rendimiento de pastos se obtuvo en la época de máxima precipitación. Los mejores rendimientos (p < 0,001) se obtuvieron en el género Megathyrsus (cvs. Tanzania y Massai), con ofertas de 34,9 y 31,9 t de MS/ha/año, superiores a las de los diferentes cvs. de Urochloa. En cuanto a la disponibilidad de MS/ha/rotación, los menores valores se lograron en los cultivares Toledo y Humidicola. La calidad fue superior en la época lluviosa. El promedio alto de MS en el poco lluvioso (40,80 %) condicionó bajos valores de PB (6,85 %), bajo contenido energético (1,57 Mcal/kg), baja digestibilidad (55,7 %) y altos contenidos de FDN (74,2 %). Conclusiones; El rendimiento promedio y la oferta de pastos de las especies fueron aceptables para las condiciones edafoclimáticas imperantes en el ecosistema, ya que no se utilizó riego ni fertilización externa; aunque disminuyeron en la época poco lluviosa, al igual que la calidad nutritiva. El género Megathyrsus se destacó por sus mejores indicadores de producción, mientras que Arachispintoi Krapov. & W.C. Greg sobresalió por su alto valor nutritivo. Palabras clave: composición química, oferta, producción de biomasa Objective: To characterize the agronomic performance and chemical composition of cultivated species in a Voisin rational grazing system, in the humid tropic of Los Santos, Panama. Materials and Methods: The yield and nutritional value of a group of cultivated species were evaluated, with 24 paddocks and 1,9 days of average occupation. The system was grazed with 53 Zebu-based steers and their F1 and F2 crossings (Zebu x Holstein). The main indicators measured were: total forage production (kg DM/ha/rotation), forage supply per species and percentages of DM, CP, ADF, NDF, IVDMD30, ME, Ash, Ca and P. The data were processed using simple classification variance analysis. The statistical package IBMR SPSSR Statistics version 22 was used. Results: Forage production varied between 3 344 and 4 442 kg DM/ha/rotation. The highest pasture yield was obtained in the rainy season. The best yields (p < 0,001) were obtained in the genus Megathyrsus (cvs. Tanzania and Massai), with offers of 34,9 and 31,9 t DM/ha/year, higher than those of the different Urochloa cvs. Regarding the availability of DM/ha/rotation, the lowest values were achieved in the cultivars Toledo and Humidicola. The quality was higher in the rainy season. The high average DM in the dry season (40,80 %) conditioned low CP values (6,85 %), low energy content (1,57 Mcal/kg), low digestibility (55,7 %) and high contents of NDF (74,2%). Conclusions: The average yield and pasture supply of the species were acceptable for the prevailing edaphoclimatic Conditions in the ecosystem, since no irrigation or external fertilization was used; although they decreased in the dry season, as well as the nutritional quality. The genus Megathyrsus stood out for its better production indicators; while Arachis pintoi Krapov. & W.C. Greg stood out for its high nutritional value. Keywords: chemical composition, supply, biomass production
Autonomic nervous system (ANS) activity can modify cardiovascular parameters in response to nociceptive stimuli or drugs in anesthetized animals. The aim of this study was to determine if a surgical ...nociceptive stimulus and morphine, ketamine, and dobutamine administration would modify ANS activity observed as a change in the mean parasympathetic tone activity (PTAm) in anesthetized horses. In 20 anesthetized horses, heart rate (HR), mean arterial pressure (MAP), and PTAm were monitored before and 1, 3, and 5 min after surgical incision, and before and 10 min after the administration of morphine (0.2 mg/kg IV). If nystagmus or spontaneous ventilation was observed, ketamine (0.5 mg/kg IV) was given, and the three variables were registered before and 3 and 5 min afterward. If MAP reached ≤62 mmHg, a dobutamine infusion was administered, and the three variables were recorded before and 5 min after starting/increasing the infusion (0.25 μg/kg/min IV every 5 min). The three variables were registered before and 1, 3, and 5 min after a PTAm decrease of ≥20%, HR increase of ≥10%, or MAP increase of ≥20%. The PTAm decreased 3 min after the administration of ketamine and 1 min after a PTA event. The surgical incision, dobutamine, and morphine did not modify PTAm. The absence of changes in ANS activity after the nociceptive stimulus and lack of correlation between PTAm and HR or MAP suggest that PTAm is a poor indicator of sympathetic activation under the study conditions. Ketamine seems to affect ANS activity by decreasing PTAm.
Equivalence – Equivalence responding (Barnes et al., 1997), based on derived or non-explicitly trained relational responding, supports a behaviour-analytic model of analogical reasoning. Conditional ...discriminations are the most common procedure used to train its prerequisites. In this exploratory work we test Vaughan’s (1988) simple discrimination procedure instead to derive Eq-Eq responses in children. Two factors were assessed: type of reinforcer used (primary or secondary) and age of participants (9-10 or 12-13 years). The procedure successfully leaded to the derivation of equivalence – equivalence responses, and both factors influenced the results: selecting older children and applying primary reinforcement leaded to faster learning and better results in the equivalence – equivalence test. No interaction between factors was found. This training procedure can provide a new way to investigate the behavioural prerequisites of this important ability
PDF
