Hemodynamic variables in piglets anesthetized with isoflurane or propofol, kept under spontaneous ventilation and FIO2 of 0. 5 / Variáveis hemodinâmicas em suínos anestesiados com isoflurano ou propofol, mantidos sob ventilação espontânea e FIO2 de 0,5

This study aimed to evaluate comparatively the effects of propofol or isoflurane on hemodynamic variables in piglets that received inspired oxygen fraction (FIO2) of 0.5 under spontaneous ventilation. Therefore, sixteen piglets weighing 16±1.1kg, were randomly divided into two groups: GI (Isoflurane and FIO2 of 0.5) and GP (Propofol and FIO2 of 0.5). Heart rate (HR), systolic, diastolic and mean arterial pressure (SAP, DAP and MAP), central venous pressure (CVP), cardiac output (CO), mean pulmonary arterial pressure (mPAP) and mean capillary pulmonary pressure (mCPP) were assessed 40 minutes after anesthetic induction (T0), followed by 15 minutes intervals (from T15 to T60). The variables cardiac index (CI), stroke volume (SV), stroke index (SI), total peripheral resistance (TPR), total peripheral resistance index (TPRI), pulmonary vascular resistance (PVR), and pulmonary vascular resistance index (PVRI) were calculated. SAP and TPRI were significantly different between groups at T30 and T60 (P< 0.05) with higher GP values being recorded. There were no differences in the other variables, however, GP presented mean closer to normality on most of the analyzed variables. Therefore, we conclude that total intravenous anesthesia with propofol presented greater stability of the hemodynamic variables evaluated.(AU)

O objetivo deste estudo foi avaliar comparativamente os efeitos do propofol ou do isoflurano sobre as variáveis hemodinâmicas em leitões que receberam fração inspirada de oxigênio (FIO2) de 0,5 sob ventilação espontânea. Dezesseis leitões, pesando 16±1,1kg, foram divididos aleatoriamente em dois grupos: GI (isoflurano e FIO2 de 0,5) e GP (propofol e FIO2 de 0,5). A frequência cardíaca (FC), a pressão arterial sistólica, a diastólica e a média (PAS, PAD e PAM), a pressão venosa central (PVC), o débito cardíaco (DC),a pressão média da artéria pulmonar (PAPm) e a pressão média capilar pulmonar (PCPm) foram avaliados 40 minutos após a indução anestésica (T0), seguida por intervalos de 15 minutos (de T15 a T60). As variáveis índice cardíaco (IC), volume sistólico (VS), índice sistólico (SI), resistência periférica total (RPT), índice de resistência periférica total (IRPT), resistência vascular pulmonar (RVP) e índice de resistência vascular pulmonar (IRVP) foram calculadas. PAS e IRPT foram significativamente diferentes entre os grupos em T30 e T60 (P<0,05) com maiores valores de GP sendo registrados. Não houve diferenças nas demais variáveis, entretanto o GP apresentou médias próximas da normalidade na maioria das variáveis analisadas. Portanto, concluiu-se que a anestesia intravenosa total com propofol apresentou maior estabilidade das variáveis hemodinâmicas avaliadas.(AU)

Blood gas analysis in pigs submitted to different concentrations of nitrous oxide or oxygen, under different ventilatory modalities / Estudo hemogasométrico em suínos submetidos a diferentes concentrações de óxido nitroso ou oxigênio, sob diferentes modalidades ventilatórias

The effects of different concentrations of oxygen and nitrous oxide on blood gas parameters in pigs maintained under spontaneous or pressure-controlled ventilation, with or without positive end-expiratory pressure (PEEP), were compared. Forty-eight pigs were randomly divided into six groups, submitted to different concentrations of compressed air or N2O, associated with different fractions of inspired oxygen (FiO2). The group subject to 30% of compressed air (GA30) showed the closest proximity to the physiological range of partial pressure (PaO2) expected for the species. For oxygen saturation (SaO2), the values obtained were below the lower physiological limit in the group administered 30% N2O (GN30). Use of PEEP positively interfered in PaCO2 independent of FiO2, however, its effectiveness can be compromised when complemented by N2O-based anesthesia. For SaO2, only GN30 showed values lower than adequate for maintaining tissue oxygenation. The pH, base deficit and bicarbonate in arterial blood were influenced by FiO2 and N2O. In conclusion, the use of compressed air maintains blood gas parameters at their most stable, especially GA30 and PEEP, which seemed to positively influence the experimental groups, with some interference from FiO2 and N2O.(AU)

Compararam-se os efeitos de diferentes concentrações do óxido nitroso ou oxigênio sobre variáveis hemogasométricas, em suínos mantidos em ventilação espontânea ou controlada à pressão, associada ou não à pressão expiratória final positiva (PEEP). Foram utilizados 48 porcos, distribuídos em seis grupos. Administraram-se diferentes concentrações de ar comprimido ou N2O, associadas a diversas frações de oxigênio inspirado (FiO2). O grupo sujeito a 30% de ar comprimido (GA30) mostrou maior proximidade do intervalo fisiológico da pressão parcial de oxigênio (PaO2). Para a saturação de oxigênio (SaO2), observaram-se valores aquém do limite inferior fisiológico no grupo administrado com 30% de N2O (GN30). A utilização da PEEP é capaz de interferir positivamente na PaCO2, independentemente da FiO2, porém tem a efetividade comprometida quando há complemento da anestesia com o N2O. Para a SaO2, apenas o GN30 esboçou valores inferiores aos adequados para manutenção da oxigenação tecidual. O pH, o déficit base e o bicarbonato no sangue arterial foram influenciados pela FiO2 e pelo N2O. Concluiu-se que o uso do ar comprimido mantém os parâmetros hemogasométricos mais estáveis, com destaque para o GA30 e a PEEP, o que parece influenciar positivamente os grupos experimentais, mas com interferência da FiO2 e do N2O.(AU)

Monitoring of the crystallization of zeolite LTA using Raman and chemometric tools.

LTA zeolite is used both in industry as well as in laboratories, because of its spatial-specific structure which is useful in gas adsorption and in ion exchange separation. At-line reaction monitoring and multivariate analysis of data, such as Principal Component Analysis (PCA), are fundamentals of the Process Analytical Technology (PAT), which consists of the use of analyzers with rapid detection and low sample preparation for analysis during the process stream. In this work, an optimization of zeolite LTA synthesis was performed aiming to obtain nanocrystals and the synthesis was monitored using Raman spectroscopy and PCA. A reaction mixture of 6.2Na2O : Al2O3 : 2SiO2 : 128H2O was used and it was possible to obtain a small particle size and high crystallinity after 72 h of synthesis at 25 °C. The synthesis was monitored at-line, using Raman spectroscopy in both liquid and solid phases. The extension of the reaction could be clearly observed by the PCA scores. As expected, the liquid phase presented changes over time, but the solid phase presented three specific stationary conditions at 0-24 h, 32-56 h and 72-80, related to the beginning of the reaction, the nucleation process, and the crystal formation, respectively. In addition, it was possible to identify the intermediates of the reaction and with the aid of PCA to monitor the reaction close to the real time.

Estimates of genetic parameters and eigenvector indices for milk production of Holstein cows.

The objectives of the present study were to estimate genetic parameters of monthly test-day milk yield (TDMY) of the first lactation of Brazilian Holstein cows using random regression (RR), and to compare the genetic gains for milk production and persistency, derived from RR models, using eigenvector indices and selection indices that did not consider eigenvectors. The data set contained monthly TDMY of 3,543 first lactations of Brazilian Holstein cows calving between 1994 and 2011. The RR model included the fixed effect of the contemporary group (herd-month-year of test days), the covariate calving age (linear and quadratic effects), and a fourth-order regression on Legendre orthogonal polynomials of days in milk (DIM) to model the population-based mean curve. Additive genetic and nongenetic animal effects were fit as RR with 4 classes of residual variance random effect. Eigenvector indices based on the additive genetic RR covariance matrix were used to evaluate the genetic gains of milk yield and persistency compared with the traditional selection index (selection index based on breeding values of milk yield until 305 DIM). The heritability estimates for monthly TDMY ranged from 0.12 ± 0.04 to 0.31 ± 0.04. The estimates of additive genetic and nongenetic animal effects correlation were close to 1 at adjacent monthly TDMY, with a tendency to diminish as the time between DIM classes increased. The first eigenvector was related to the increase of the genetic response of the milk yield and the second eigenvector was related to the increase of the genetic gains of the persistency but it contributed to decrease the genetic gains for total milk yield. Therefore, using this eigenvector to improve persistency will not contribute to change the shape of genetic curve pattern. If the breeding goal is to improve milk production and persistency, complete sequential eigenvector indices (selection indices composite with all eigenvectors) could be used with higher economic values for persistency. However, if the breeding goal is to improve only milk yield, the traditional selection index is indicated.

Avaliação de parâmetros cardiovasculares, ventilatórios e hemogasométricos de coelhos anestesiados com isofluorano ou sevofluorano e submetidos à ventilação espontânea ou controlada a volume / Assessment of cardiovascular, ventilatory and blood gasometric parameters of rabbits anesthetized with isoflurane or sevoflurane and undergoing volume-controlled or spontaneous ventilation

Avaliaram-se as ventilações mecânica controlada a volume e espontânea, por meio das variáveis hemogasométricas, cardiovasculares e ventilométricas. Distribuíram-se 28 coelhos nos grupos: GIVC (isofluorano e ventilação controlada a volume), GIVE (isofluorano e ventilação espontânea), GSVC (sevofluorano e ventilação controlada a volume) e GSVE (sevofluorano e ventilação espontânea). Induziu-se por máscara, com isofluorano (GIVE e GIVC) ou sevofluorano (GSVE e GSVC) a 1,5 CAM, em oxigênio a 100%. Para manutenção anestésica, reajustou-se para 1 CAM. No GIVC e no GSVC, administrou-se rocurônio, na dose de 0,6mg/kg, seguida de infusão contínua na mesma dose de 0,6mg/kg/h. No GIVE e no GSVE, foi administrado NaCl 0,9% em vez de rocurônio. Iniciou-se a ventilação controlada ajustando-a de maneira a obter capnometria entre 35 e 45mmHg. Mensuraram-se os parâmetros 60 minutos após a indução anestésica (M0), 15 minutos após o bolus de rocurônio ou NaCl 0,9% (M15) e a cada 15 minutos (M30, M45 e M60). Evidenciou-se hipercapnia e acidose em GIVC, GSVC e GSVE. Concluiu-se que a ventilação mecânica controlada a volume não foi capaz de manter a normocapnia em coelhos, gerando acidose, principalmente quando se utilizou sevofluorano. O uso do isofluorano demonstrou maior estabilidade anestésica que o sevofluorano nesta.

The volume-controlled mechanical ventilation and spontaneous ventilation, through haemogasometric, cardiovascular and spirometry variables were evaluated. Twenty-eight rabbits were distributed into two groups: GIVC (isoflurane and volume-controlled ventilation), GIVE (isoflurane and spontaneous ventilation), GSVC (sevoflurane and volume-controlled ventilation) and GSVE (sevoflurane and spontaneous ventilation). Induction was performed by mask with isoflurane (GIVE and GIVC) or sevoflurane (GSVE and GSVC) at 1.5 MAC in 100% oxygen. To maintain anesthesia, MAC was reset to 1. In GIVC and GSVC groups, rocuronium was administered at a dose of 0.6 mg/kg followed by its continuous infusion (0.6 mg/kg/h). In GSVE and GIVE, 0.9% NaCl was administered instead of rocuronium. Controlled ventilation was started by adjusting the capnometry in order to obtain values between 35 and 45 mmHg. Parameters were measured 60 minutes after induction of anesthesia (M0), 15 minutes after the bolus of rocuronium or 0.9% NaCl (M15) and every fifteen minutes (M30, M45 and M60). Hypercapnia and acidosis was evident in GIVC, GSVC and GSVE. We concluded that the volume-controlled mechanical ventilation was not able to maintain normocapnia in rabbits, producing acidosis in them, especially when using sevoflurane. The use of isoflurane showed greater stability than the sevoflurane anesthetic in the species studied.

Interval multivariate curve resolution in the dereplication of HPLC-DAD data from Jatropha gossypifolia.

INTRODUCTION: Jatropha gossypifolia has been used quite extensively by traditional medicine for the treatment of several diseases in South America and Africa. This medicinal plant has therapeutic potential as a phytomedicine and therefore the establishment of innovative analytical methods to characterise their active components is crucial to the future development of a quality product. OBJECTIVE: To enhance the chromatographic resolution of HPLC-UV-diode-array detector (DAD) experiments applying chemometric tools. METHODS: Crude leave extracts from J. gossypifolia were analysed by HPLC-DAD. A chromatographic band deconvolution method was designed and applied using interval multivariate curve resolution by alternating least squares (MCR-ALS). RESULTS: The MCR-ALS method allowed the deconvolution from up to 117% more bands, compared with the original HPLC-DAD experiments, even in regions where the UV spectra showed high similarity. The method assisted in the dereplication of three C-glycosylflavones isomers: vitexin/isovitexin, orientin/homorientin and schaftoside/isoschaftoside. CONCLUSION: The MCR-ALS method is shown to be a powerful tool to solve problems of chromatographic band overlapping from complex mixtures such as natural crude samples.

The transition from quantity to quality: a neglected causal mechanism in accounting for social evolution.

Students of social evolution are concerned not only with the general course it has followed, but also with the mechanisms that have brought it about. One such mechanism comes into play when the quantitative increase in some entity, usually population, reaching a certain threshold, gives rise to a qualitative change in the structure of a society. This mechanism, first recognized by Hegel, was seized on by Marx and Engels. However, neither they nor their current followers among anthropologists have made much use of it in attempting to explain social evolution. But as this paper attempts to show, in those few instances when the mechanism has been invoked, it has heightened our understanding of the process of social evolution. And, it is argued, if the mechanism were more widely applied, further understanding of the course of evolution could be expected to result.

A Theory of the Origin of the State: Traditional theories of state origins are considered and rejected in favor of a new ecological hypothesis.

In summary, then, the circumscription theory in its elaborated form goes far toward accounting for the origin of the state. It explains why states arose where they did, and why they failed to arise elsewhere. It shows the state to be a predictable response to certain specific cultural, demographic, and ecological conditions. Thus, it helps to elucidate what was undoubtedly the most important single step ever taken in the political evolution of mankind.