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Five different physiological functions of the rabbit (hard faeces and urine excretion, food and water intake and locomotor activity) were registered during LD 12:12 and during continuous light conditions (LL).(1) In LD 12:12 a strong synchronization of the five parameters existed. The minima of all functions consistently occurred during the hours of light. The nocturnal percentage of overall 24-hr events was increased significantly in 'hard faeces excretion' (66±8 (S.D.) %), 'water intake' (64±15 (S.D.) %) and 'urine excretion' (58±10 (S.D.) %). The nocturnal percentage of locomotor activity was significantly increased during the dark-hours in 9 out of 14 animals. In the other five individuals prominent peaks were present even during the photoperiod. On the average of all 14 animals 5S±13 (S.D.) % of the 24 hr events of locomotor activity occurred during the night. Despite a trough during the cessation of hard faeces excretion the events of food intake were not elevated significantly during the dark hours.(2) During LL the synchronization of the five functions within each animal persisted during the complete 90-day LL period. A free-running circadian rhythm with-: = 24.8±0.5 (S.D.) hr was present in the four rabbits kept in LL conditions within 5-16 days after the withdrawal of the zeitgeber.(3) In addition to the circadian period the power spectrum analysis of data obtained during LD 12:12 revealed significant ultradian periods of an average period length of 11,6 hr (hard faeces and urine excretion), 8 hr (food and water intake, locomotor activity) and 4 hr (food intake, locomotor activity). During the free-run ultradian periods of 8 and 3.2-4.2 hr were significant in almost all parameters.(4) During LL the level of locomotor activity was reduced for 13±16 (S.D.) %, the events of food intake were increased for 17±12 (S.D.) %.(5) The reinserted LD 12:12 zeitgeber re-entrained the circadian rhythms within 25-45 days.(6) These results provided evidence of a predominant nocturnality of the rabbits under investigation.

The free-running circadian rhythms of five behavioral functions of the rabbit were masked by unsignalled restricted food access (RF). The rhythms were reorganized immediately, a large part of events being assembled around the end of food availability. In addition to masking a slower process of entrainment was running: a component of anticipatory activity (AA) was established 1–3 h before food access. AA consolidated in continuation of the camouflaged free-running rhythm. The time of AA establishment correlated significantly with the phase angle difference (PAD) between free-running rhythm and RF: it decreased with decreasing positive PAD. With the consolidation of AA, the rhythms had attained a stable phase relation to RF. At the termination of RF, the circadian rhythms started to free-run again, the phase being dependent from that of the preceding RF schedule. The period length of the RF zeitgeber (TRF) had some impact on tau of the circadian rhythm. This aftereffect was most evident after termination of TRF<24 h: the free-running rhythm continued for up to 49 days with a tau <24 h and turned longer thereafter. The results demonstrate the entrainment of circadian rhythms of the rabbit by RF in addition to masking.

Objectives: To compare the pharmacokinetics of bromfenac among normal subjects and renally compromised patients and patients with end-stage renal disease.Methods: Bromfenac pharmacokinetics were examined after a single 50 mg oral dose in 18 subjects with normal kidney function, 12 subjects with decreased kidney function, and 10 dialysis-dependent subjects. Protein binding was assessed by equilibrium dialysis.Results: Mean peak concentrations and areas under the concentration versus time curve ranged from 3.3 to 3.9 μg/ml and 5.1 to 6.9 μg · hr/ml, respectively. The mean unbound fraction in the subjects receiving dialysis (0.29%) was nearly twice that in the subjects with normal kidney function (0.17%) and in the subjects with impaired kidney function (0.16%), but no differences were detected in clearance, volume of distribution, or their free fraction-corrected counterparts. Bromfenac half-life nearly doubled in the impaired and dialysis groups but was shorter than the anticipated 8-hour dose interval. Eight subjects had a total of 11 study events; none were serious and all were self-limited.Conclusions: These findings suggest that no dosage adjustment is necessary in patients with impaired kidney function, but clinical monitoring appropriate for their individual condition is recommended.

Over the last 15 years electron transfer activation has emerged as a valuable concept for accomplishing novel reactions and has found widespread application in the selective transformation of increasingly complex molecules. This review presents in a conceptualized manner the vast number of radical cation reactions obtained after chemical, electrochemical, and photoinduced one-electron oxidation. To familiarize the reader with the concepts of electron transfer a simple and straightforward classification of radical cation reactions has been devised to allow the presentation of a manifold of reactions in a readily understandable manner. Whenever possible, thermochemical and kinetic data are provided. A terra incognitawith a huge potential for chemical synthesis is opened by activation of organic substrates by one-electron transfer: Reactions of radical cation can be extremely selective when proper control over the primary and secondary reactions is attained. An analysis that combines the observed reactivity patterns of numerous instructive examples with thermodynamic and kinetic data leads to a useful categorization of radical cation reactivity and reveals the principles governing their mode of action. This should facilitate the directed planning of synthetic transformations with these intermediates.

Using small (50-100 μm) and large (800-1000 μm) polystyrene particles as a marker substance, transit through the gastrointestinal tract of the rabbit was studied during the formation of hard and soft faeces (caecotrophe). Both fractions of the marker were transported at an equal rate during soft faeces formation. During the formation of hard faeces a significantly higher amount of small particles was present in the caecum, whereas in the distal colon and rectum the number of large particles was elevated significantly.

The circadian caecotrophy rhythm was synchronized with the light-dark cycle of 12 : 12 h. During this the rabbits practised caecotrophy regularly during the light period. While most rabbits manifested 1 caecotrophy per 24 h (monophasic caecotrophy), some had an additional caecotrophy during the dark period (diphasic caecotrophy). During continuous light the circadian caecotrophy rhythm ran free monophasically, even in those rabbits which were diphasic under the preceding 12 : 12 regime. The average period length amounted to 24·7 ± 0·3 h. Following restoration of the 12 : 12 routine animals reestablished their original caecotrophy pattern.In a further test the caecotrophy pattern remained constant during a constant 12 : 12 regimen, but changed in 7 of 16 animals when the photoperiod was reduced first to 60 min and then to 2 × 60 min light every 24 h. The reduction of the lit time resulted in an increased occurrence of diphasic animals. Details of synchronization of the caecotrophy rhythm with the different light-dark schedules are given. These results accord with data obtained in nocturnal rodent species.

By means of dynamic NMR (DNMR) investigations the dynamic behaviour of several crowded enol derivatives 5–11 and of the enols 12 and 13 has been studied. The NMR data are in agreement with the presence of vinyl propeller structures in solution, which fits the results of X-ray structural analysis. As deduced from a comparison with electrochemical data for the compounds investigated a severe electronic influence of the residue R attached at the enol ether oxygen atom on the rotation barriers can be ruled out. For Mes2C&z.dbd6;C(Ph)OR systems, two different kinds of dynamic processes have been deduced on the basis of the DNMR data: first, an isolated rotation of the phenyl ring with a low activation barrier and, secondly, a correlated rotation of the two β-mesityl rings with a substantially higher barrier.

The essay discusses the idea that art can have a therapeutic effect on the relationship of human beings to nature and on environmental degradation as a consequence of the development of modern society, as evidenced in the graphic art of German conceptual artist Joseph Beuys. The author focuses on an interpretation of Beuys' theoretical positions on drawing and embeds these in the broader history of environmental philosophy. He also remarks on the notion of myth in Beuys' art.

The direction of temporary phase shifts depends on the timing of the light signal in the dark period (1800-0600). Delays predominated following signals between 2100 and 2400, while advances tended, even more uniformly, to follow signals given between 0100 and 0400. In one animal the caecotrophy rhythm split into 2 components after a light signal at 0400, while in another it was so disturbed that the signal was followed by a coprostasis of 10 days. The phase responses to light stimuli of the rabbit caecotrophy rhythm correspond well with those obtained in nocturnal rodents.

An automatic dropping-applicator for fresh cigarette smoke condensate is described. The new applicator makes it possible to apply separately a solvent and the smoke condensate produced by a capillary press. 15 animals can be treated simultaneously

The donor–acceptor dye cassettes 1–4 were designed to capture energy at a single wavelength and to convert it to well-resolved, intense fluorescence emissions; in practice, Stokes’ shifts of 40–148 nm, quantum yields of 0.12–0.60, and efficient energy transfer was demonstrated.

The constrained dye 3 was prepared and shown to have a sharper, red-shifted, and more intense fluorescence emission than the 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY®) dye 2 in which the aryl groups can rotate freely.

A mechanical and electronic unit that records circadian faecal excretion by rabbits is described.

The photograph "Lagoon 2, 2011," by Barbara Burghart-Perreault, which was nominated for the journal's National Prize Winner contest is presented.

The synthesis is achieved by stereocontrolled C=C bond formation.

Temporary hemiepiphysiodesis is a relatively minor surgical procedure in the growing child to allow guided growth to correct angular deformities. Blount staples (Stryker Howmedica, Kiel, Germany) have been used effectively for the past 50 years for physeal stapling; their limitations are poor mechanical purchase and easy extrusion from bone, implant breakage, and potential for physeal damage and permanent closure. Recently, an alternative device to Blount staples called the eight-Plate (Orthofix, McKinney, Texas) has been presented for hemiepiphysiodesis and guided growth. Their theoretical advantages over Blount staples include higher stability, faster correction of the deformity, and fewer complications.We performed a study in a pig model to compare the rate of angular deformity correction and implant extrusion after hemiepiphysiodesis with Blount staples and eight-Plates. In all animals, medial hemiepiphysiodesis was performed in the right proximal tibia with the eight-Plate and the left proximal tibia with the Blount staple. The medial slope angle, medial tibial plateau angle, proximal implant angle, distal implant angle, and distance of the body of the implant from the medial tibial cortex were measured on radiographs of the knee joints performed every 4 weeks. The angles of correction showed statistically significantly earlier effect on physeal guided growth of the eight-Plates compared to the Blount staples. Implant displacement/extrusion was statistically significantly lower for the eight-Plate. In this animal model, eight-Plates are significantly more effective than Blount staples for guided growth after temporary hemiepiphysiodesis.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The author reflects on the purpose of progressive thought and conception. He asserts that thinking means to distance oneself from immediate existence. He contradicts the notion that thought and theory have had no effect over the last few decades. He stresses the need for alternative forms of thinking to address the major problem facing the world, that is the exploitation of the Third World by the First World.

Reports on the closure of Chanute Air Force Base in Rantoul, Illinois. Impact of the base closure on its residents; Information on the base; How the town of Rantoul survived after the base closure. INSET: Museum is a link to the past.

Focuses on the technique developed by scientists from the University of Illinois-Chicago to make soybeans resistant to soybean cyst nematode infestation. Characteristic incorporated in the soybean's genes to make its root resistant to the nematode; Comments from the project's leaders.

Reports on the agreement signed by Applied CarboChemicals with four national laboratories to develop and commercialize a process of converting corn into commercial chemicals. Importance of the process in the United States' reliance on imported petroleum products.