1,104 research outputs found
Comparison of Subjective Responses to Oral and Intravenous Alcohol Administration under Similar Systemic Exposures
Objective
To test whether an individual's subjective responses to alcohol are similar when the breath alcohol concentration (BrAC) trajectory resulting from oral administration is matched by intravenous administration.
Background
Individuals perceive the effects of alcohol differently, and the variation is commonly used in research assessing the risk for developing an alcohol use disorder. Such research is supported by both oral and intravenous alcohol administration techniques, and any differences attributable to the route employed should be understood.
Methods
We conducted a 2âsession, withinâsubject study in 44 young adult, healthy, nonâdependent drinkers (22 females and 22 males). In the first session, subjects ingested a dose of alcohol which was individually calculated, on the basis of total body water, to yield a peak BrAC near 80 mg/dl, and the resulting BrAC trajectory was recorded. A few days later, subjects received an intravenous alcohol infusion rate profile, preâcomputed to replicate each individual's oral alcohol BrAC trajectory. In both sessions, we assessed 4 subjective responses to alcohol: SEDATION, SIMULATION, INTOXICATION, and HIGH; at baseline and frequently for 4 hours. We compared the individualsâ baselineâcorrected responses at peak BrAC and at halfâpeak BrAC on both the ascending and descending limbs. We also computed and compared Pearsonâproduct moment correlations of responses by route of administration, the Mellanby measure of acute adaptation to alcohol, and the area under the entire response curve for each subjective response.
Results
No significant differences in any measure could be attributed to the route of alcohol administration. Eleven of 12 response comparisons were significantly correlated across the routes of alcohol administration, with 9 surviving correction for multiple measures, as did the Mellanby effect and area under the response curve correlations.
Conclusion
The route of alcohol administration has a minimal effect on subjective responses to alcohol when an individual's BrAC exposure profiles are similar
The autophagic machinery is necessary for removal of cell corpses from the developing retinal neuroepithelium
12 pĂĄginas, 8 figuras -- PAGS nros. 1279-1290Autophagy is a homoeostatic process necessary for the clearance of damaged or superfluous proteins and organelles. The recycling of intracellular constituents also provides energy during periods of metabolic stress, thereby contributing to cell viability. In addition, disruption of autophagic machinery interferes with embryonic development in several species, although the underlying cellular processes affected remain unclear. Here, we investigate the role of autophagy during the early stages of chick retina development, when the retinal neuroepithelium proliferates and starts to generate the first neurons, the retinal ganglion cells. These two developmental processes are accompanied by programmed cell death. Upon treatment with the autophagic inhibitor 3-methyladenine, retinas accumulated numerous TdT-mediated dUTP nick-end labelling-positive cells that correlated with a lack of the âeat-meâ signal phosphatidylserine (PS). In consequence, neighbouring cells did not engulf apoptotic bodies and they persisted as individual cell corpses, a phenotype that was also observed after blockade of phagocytosis with phospho-L-Serine. Supplying the retinas with methylpyruvate, a cell-permeable substrate for ATP production, restored ATP levels and the presentation of PS at the cell surface. Hence, engulfment and lysosomal degradation of apoptotic bodies were also re-established. Together, these data point to a novel role for the autophagic machinery during the development of the central nervous systemThis research was supported by grants from the Spanish Ministerio de EducaciĂłn y Ciencia (BFU2006-00508 to PB and SAF2007-66175 to EJdlR) and Comunidad de Madrid (CCG06-CSIC/SAL-0821 to PB). MAM is a FPU Fellow and PB is a RamĂłn y Cajal Fellow (both Ministerio de EducaciĂłn y Ciencia programs)Peer reviewe
Two-dimensional domain structures in Lithium Niobate via domain inversion with ultrafast light
Periodic inversion of ferroelectric domains is realized in a lithium niobate crystal by focused femtosecond near-infrared laser beam. One and two-dimensional domain patterns are fabricated. Quasi-phase matched frequency doubling of 815nm light is demonstrated in a channel waveguide with an inscribed periodic domain pattern with conversion efficiency as high as 17.45%.Peer ReviewedPostprint (published version
Penggunaan Ekstraksi Fasa Padat Untuk Analisis Tetrasiklin Dalam Contoh Udang
A great quantity of Indonesian frozen prawns were exported to Japan and America. Unfortunately these products have often been rejected due to their content of tetracycline derivative residues. Qualitative analysis of frozen prawn samples being exported by means of HPLC, indicated that they are contaminated by oxytetracycline and tetracycline residues. A problem of quantitative analysis of such residues could be due to several peaks of the matrix being eluted closely to the peaks of the tetracycline derivatives. An experiment was carried out to eliminate the peaks of the matrix origin using SPE (Solid Phase Extraction) in order to quantify the derivatives more accurately. Application of SPE in the sample pretreatment is useful not only for separating the solute being analyzed from the matrixs, but also for concentrating the tetracycline derivatives of the extract. The recovery of SPE column elution process was about 90% and the SPE octadecyl (1 ml) column capacity for oxytetracycline, tetracycline, demeclocycline and doxycycline i.e. 2.4-7.9 ug; 3.5-11.8 ug; 3.4-11.2 ug and 17.3-57.5 ug respectively
Modeling the Dynamics of Long-Term Variability of Hydroclimatic Processes
The stochastic analysis, modeling, and simulation of climatic and hydrologic processes such as precipitation, streamflow, and sea surface temperature have usually been based on assumed stationarity or randomness of the process under consideration. However, empirical evidence of many hydroclimatic data shows temporal variability involving trends, oscillatory behavior, and sudden shifts. While many studies have been made for detecting and testing the statistical significance of these special characteristics, the probabilistic framework for modeling the temporal dynamics of such processes appears to be lacking. In this paper a family of stochastic models that can be used to capture the dynamics of abrupt shifts in hydroclimatic time series is proposed. The applicability of such ââshifting mean modelsâ â are illustrated by using time series data of annual Pacific decadal oscillation (PDO) indices and annual streamflows of the Niger River. 1
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