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Notes: The mechanism of the reaction CH4+O(1D2)→CH3+OH was investigated by ultrafast, time-resolved and state-resolved experiments. In the ultrafast experiments, short ultraviolet pulses photolyzed ozone in the CH4⋅O3 van der Waals complex to produce O(1D2). The ensuing reaction with CH4 was monitored by measuring the appearance rate of OH(v=0,1;J,Ω,Λ) by laser-induced fluorescence, through the OH A←X transition, using short probe pulses. These spectrally broad pulses, centered between 307 and 316 nm, probe many different OH rovibrational states simultaneously. At each probe wavelength, both a fast and a slow rise time were evident in the fluorescence signal, and the ratio of the fast-to-slow signal varied with probe wavelength. The distribution of OH(v,J,Ω,Λ) states, Pobs(v,J,Ω,Λ), was determined by laser-induced fluorescence using a high-resolution, tunable dye laser. The Pobs(v,J,Ω,Λ) data and the time-resolved data were analyzed under the assumption that different formation times represent different reaction mechanisms and that each mechanism produces a characteristic rovibrational distribution. The state-resolved and the time-resolved data can be fit independently using a two-mechanism model: Pobs(v,J,Ω,Λ) can be decomposed into two components, and the appearance of OH can be fit by two exponential rise times. However, these independent analyses are not mutually consistent. The time-resolved and state-resolved data can be consistently fit using a three-mechanism model. The OH appearance signals, at all probe wavelengths, were fit with times τfast(approximate)0.2 ps, τinter(approximate)0.5 ps and τslow(approximate)5.4 ps. The slowest of these three is the rate for dissociation of a vibrationally excited methanol intermediate (CH3OH*) predicted by statistical theory after complete intramolecular energy redistribution following insertion of O(1D2) into CH4. The Pobs(v,J,Ω,Λ) was decomposed into three components, each with a linear surprisal, under the assumption that the mechanism producing OH at a statistical rate would be characterized by a statistical prior. Dissociation of a CH4O* intermediate before complete energy randomization was identified as producing OH at the intermediate rate and was associated with a population distribution with more rovibrational energy than the slow mechanism. The third mechanism produces OH promptly with a cold rovibrational distribution, indicative of a collinear abstraction mechanism. After these identifications were made, it was possible to predict the fraction of signal associated with each mechanism at different probe wavelengths in the ultrafast experiment, and the predictions proved consistent with measured appearance signals. This model also reconciles data from a variety of previous experiments. While this model is the simplest that is consistent with the data, it is not definitive for several reasons. First, the appearance signals measured in these experiments probe simultaneously many OH(v,J,Ω,Λ) states, which would tend to obfuscate differences in the appearance rate of specific rovibrational states. Second, only about half of the OH(v,J,Ω,Λ) states populated by this reaction could be probed by laser-induced fluorescence through the OH A←X band with our apparatus. Third, the cluster environment might influence the dynamics compared to the free bimolecular reaction.

Notes: Micron-wide lines of high Tc Y-Ba-Cu-O have been successfully patterned by ablating the films with a pulsed excimer laser. The high Tc films are mounted onto a computer-controlled stepping stage and irradiated with a demagnified image of a variable-size rectangular aperture. This technique has been used for fabricating features ranging from several centimeters in length to submicron in width without any degradation in Tc. For example, a superconducting microstructure of Y-Ba-Cu-O, nominally 1 μm wide and 2.5 μm long, with a Tc (R=0) of 88 K and a Jc of 5×104 A/cm2 at 4.2 K was fabricated.

Notes: Objective: Description of a case series of 4 dogs with acute renal failure after ingestion of raisins or grapes.Case summary: Four dogs were presented with acute oliguric or anuric renal failure after a known ingestion of varying quantities of raisins or grapes. Prior to the onset of vomiting, all dogs were healthy, had no previous history of renal insufficiency, and had no exposure to other potentially nephrotoxic agents. This case series describes the clinical course and various treatment modalities used in the 4 dogs.New or unique information provided: This is the first report of clinical signs, treatment, and clinical outcome in dogs that developed renal failure after ingestion of raisins or grapes. The pathogenesis of nephrotoxicity associated with raisins and grapes remains unknown. Outcome was favorable in 2 out of the 4 cases of acute renal failure associated with raisin or grape ingestion in these dogs.

Notes: : The National Regulatory Research Institute has recommended the merger of small rural water districts in the United States. Success at bringing about merger of these districts, which contain fewer than 3,500 customers, has been highly limited. The subject of this paper is a demonstration project that may act as a catalyst to achieve the desired goal of regionalization. A computerized hydraulic data management program (CHDMP) was developed for a case study in Nelson County, Kentucky. University professors, graduate students, and two water utilities’ staffs cooperated in network analysis employing computer hardware and software. The utilities’ staffs were taught the science and technology of hydraulic model preparation, simulation, and analysis for the case study distribution systems. As an integrated system, the model contained 294 pipes, 234 nodes, six pumps, and 11 tanks. Each utility's problem areas were identified and some of the individual and mutual benefits of hydraulic planning were illustrated. A dialogue resulted between the managers. Each manager described his goals and agreed that, although political merger was not feasible at the present time, future economic factors could be a definite influence in reversing that decision.

Notes: One hundred and fifty unpremedicated children who presented for dental extractions were anaesthetised with nitrous oxide and halothane, enjurane or isofurane. Ventricular arrhythmias occurred only in the halothane group (14%). Respiratory problems and desaturation were significantly more common in the isoflurane group. Induction times differed significantly between the groups halothane 〈 enflurane 〈 isoflurane, while recovery time and induction to recovery time were significantly shorter in the enflurane group. We suggest that enflurane is the most suitable agent for anaesthetising these patients.

Notes: The effect of metoclopramide premedication on the incidence of gastric regurgitation and postoperative nausea and vomiting was studied in 101 women during gynaecological procedures performed under mask anaesthesia. All patients were premedicated orally with carmine red and temazepam. A treatment group of 48 women also received oral metoclopramide. Anaesthesia was standardised in both groups. None of the women regurgitated gastric contents. Pharyngeal pH was measured in the last 68 patients and found to be 〉 5 in all instances. Postoperative nausea and vomiting were significantly less frequent in the treatment group.