TL;DR: In this article, the authors developed a simulation model of an exhaustible resource to evaluate different resource estimation techniques, such as the Hubbert life cycle and USGS geologic analogy methods.
Abstract: Estimates of petroleum and natural gas resources vary substantially, both over time and across estimation methods. Worse, no reliable method exists for evaluating the accuracy of the various methods for estimating resources. This paper develops a simulation model of an exhaustible resource to evaluate different resource estimation techniques. Protocols for the Hubbert life cycle and USGS geologic analogy methods are developed and applied to synthetic data generated by the model. It is shown that the Hubbert method can generate an accurate estimate as early as twenty years before the peak of global production, but the geologic analogy approach overshoots the true resource base over the life cycle of the resource. 53 references, 17 figures, 3 tables.
TL;DR: Exogenous prostaglandin-F2 alpha reinstate sexual behavior in female paradise fish, however, responsiveness to prostaglandsins is influenced by prior sexual experience.
TL;DR: Patients who use emergency department services generally have no choice of facilities or medical personnel, and the emotional stress of the emergency situation on the patient and the fact that the baseline mental status is unknown to the medical personnel often make it difficult to determine competency for decision-making, especially in cases of refusal of treatment.
Abstract: Patients who use emergency department services generally have no choice of facilities or medical personnel This fact affects the nature of the physician-patient relationship and the moral rules that govern it Because a long-term relationship has not been developed, a more formal, legalistic relationship seems inevitable and appropriate Moreover, the emotional stress of the emergency situation on the patient and the fact that the baseline mental status is unknown to the medical personnel often make it difficult to determine competency for decision-making, especially in cases of refusal of treatment Although standards of informed consent apply in emergency care, there seem to be discrepancies between theory and practice, and emergency physicians may be more guilty than others of unjustified paternalism Ways must be found to ensure patients the greatest degree possible of autonomy and informed consent analogous to what they would have in a nonemergency doctor-patient relationship
TL;DR: Pulse labeling studies indicate that the enhancement of PRL production is highly specific inasmuch as saccharin was found to decrease the overall rate of protein synthesis in these cells, and Saccharin also causes a decrease in the rate of DNA synthesis under these treatment conditions.
Abstract: The artificial sweetener saccharin inhibits binding of epidermal growth factor (EGF) to cultured rat pituitary tumor cells (GH4C1 cells). Saccharin also causes morphological alterations in these cells, resulting in pronounced elongation, stretching, and firmer attachment of cells to the culture dishes. These alterations in cell shape are similar to those observed after treatment of GH4C1 cells with EGF and with thyrotropin-releasing hormone (TRH), both of which enhance prolactin (PRL) production in these cells. After assaying for PRL in saccharin-treated cultures, it was observed that this sweetener is also capable of stimulating PRL production two-to sixfold in a dose-dependent manner. Enhancement of PRL production can be observed at 0.5 mM saccharin, yet this is 10 times less than the saccharin concentration required to alter cell shape. These effects of saccharin on cell morphology and on PRL production are reversible in GH4C1 cell cultures. When added to cultures along with maximal concentrations of EGF or TRH, the effects of saccharin on PRL production are additive, suggesting that the actions of saccharin are mediated by a somewhat different pathway from that of the peptide hormones. Pulse labeling studies indicate that the enhancement of PRL production is highly specific inasmuch as saccharin was found to decrease the overall rate of protein synthesis in these cells. Saccharin also causes a decrease in the rate of DNA synthesis under these treatment conditions. Mitomycin C, which similarly inhibited DNA synthesis, had no effect on cell morphology or PRL production.
TL;DR: Spectrophotometric observations of emission line intensities over the spectral range 1400 A to 9600 A were made in five positions in the planetary nebula NGC 3242 as discussed by the authors, where both the weakness of the 1548 A, 1550 A C IV resonance lines and the steepness of the Balmer decrement suggest the possibility of internal dust in the nebula.
Abstract: Spectrophotometric observations of emission line intensities over the spectral range 1400 A to 9600 A were made in five positions in the planetary nebula NGC 3242. In two of the positions, both the weakness of the 1548 A, 1550 A C IV resonance lines and the steepness of the Balmer decrement suggest the possibility of internal dust in the nebula. The measured electron temperature varies little from the average value of 11,100 K, which is in reasonably good agreement with the less accurate value of 12,900 K measured from the Balmer continuum. The 4267 A C II line implies a C(2+) abundance that is much higher than that determined from the 1906 A, 1908 A C III lines. This discrepancy decreases with increasing distance from the central star. Equations used to correct for the existence of elements in other than the optically-observable ionization stages give results that are consistent and in agreement with abundances calculated using ultraviolet lines. This discrepancy decreases with increasing distance from the central star. Equations used to correct for the existence of elements in other than the optically-observable ionization stages give results that are consistent and in agreement with abundances calculated using ultraviolet lines. The logarithmicmore » abundances are He = 10.96, O = 8.64, N = 7.96, Ne = 8.04, C = 8.41, Ar = 6.15, and S = 6.51. 22 references.« less