On the differentiability of Cauchy horizons

Chrusciel and Galloway constructed a Cauchy horizon that is nondifferentiable on a dense set. We prove that in a certain class of Cauchy horizons densely nondifferentiable Cauchy horizons are generic. We show that our class of densely nondifferentiable Cauchy horizons implies the existence of densely nondifferentiable Cauchy horizons arising from partial Cauchy surfaces and also the existence of densely nondifferentiable black hole event horizons.Comment: 9 pages, LaTe

Biofeedback and progressive relaxation treatment of sleep-onset insomnia

Previous research suggests that self-defined insomniacs are distinguished from normals by high levels of anxiety and physiological arousal, which might be mitigated by muscle relaxation. This study assessed the relative effects of frontal EMG biofeedback, progressive relaxation, and a placebo set of “relaxation” exercises on the sleep of 18 onset insomniacs. Each subject was trained in one of these three methods for six half-hour sessions and slept in the laboratory for two consecutive nights before and after training. The experimental groups demonstrated significant decreases in physiological activity during training while changes in the control group were minimal. Reductions in sleep-onset time were: biofeedback group, 29.66 minutes; progressive relaxation group, 22.92 minutes; control group, 2.79 minutes. The experimental groups improved significantly ( p<.05 ) more than the control group, but did not differ from each other. No significant relationships between physiological levels and sleep-onset time were found, which suggests that muscle relaxation alone was not responsible for subjects' improvements. Since 20 minutes of daily practice were required to achieve an approximate 30-minute decrease in sleep-onset time, the practical utility of the methods is questioned.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44085/1/10484_2005_Article_BF01001167.pd

Development of an Algorithm to Indicate the Right Moment of Plant Watering Using the Analysis of Plant Biomasses Based on Dahlia &times; hybrida

Water management in agriculture and horticulture has a strong ecological importance related to the necessity of optimizing the use of water resources. To achieve sustainable water use, it is necessary to optimize the time, frequency and the methods of water application. In this study, we hypothesized that the right moment for watering may be established on the grounds of the observation of the physiological state of the plant (if the plant is still in turgor) and the biomass of plant and the substrate. The proper irrigation scheduling, that is, just before the plant loses turgor, which appears at ca. 73% of LRWC in dahlias, determined with the use of the proposed measurement and computing system, makes it possible to save ca. 30% of irrigation water, in comparison to standard watering. Controlled watering also affected plant growth parameters, such as the content of chlorophyll a and b and carotenoid, as well as total and reducing sugar content (ca. 7%, 9% and 23% more than in plants watered in a standard way, respectively). Plants watered in a controlled way were 12% more compact when compared with the ones watered in a standard way. The results clearly proved that the computing system connected to scales made it possible to save water used for irrigation without a negative impact on the parameters of plant growth

Decreased Circulation in the Feline Choriocapillaris Underlying Retinal Photocoagulation Lesions

Panretinal photocoagulation is used to treat diabetic retinopathy. Measurements with SLO and microspheres show that the choriocapillaris is locally damaged under lesions in the cat retina. This damage could limit the effectiveness of photocoagulation