The Conical Sundial from Thyrrheion – Reconstruction and Error Analysis of a Displaced Antique Sundial

Summary The conical sundial from the museum Thyrrheion is found to be designed with cardinal parameters geographical latitude  ϕ = arc tan(3/5) = 30°57′50″ half cone angle   α = arc tan(4/9) = 23°57′45″ radius at equinox   r₀ = 4 unciae = 98.7mm (pes monetalis) position of the cone tip h = 18 unciae = 444.3 mm The half cone angle is equal to the angle of the ecliptic which leads to the special case of a conical sundial with the associated sphere being tangent at the day line of the winter solstice. The ratio of sides in the generating triangle 4:9 may thus be interpreted as an approximation for the angle of ecliptic. The place of finding (operation) is 10° North of the intended latitude (design). The error of the sundial's indications due to the displacement are analyzed. (Received July 15, 2000)     

Organization Change in a University Hospital: A Six Year Evaluation Report of the HORIZONS Project

Many health care organizations are currently engaged in changing the design of their health care services delivery system. The issues of cost containment, quality, and access are prominent. This paper reports on the impact of the implementation of a new organization design at one university hospital. The organization change effort (named HORIZONS) was a five year project funded in part by the Robert Wood Johnson Foundation and the Pew Charitable Trusts. In a changing health care environment, the project was undertaken with three goals in mind: (1) to maintain and enhance quality of patient care; (2) to improve the quality of working life; and (3) to accomplish this in a budget neutral manner. Initiated as a program to strengthen hospital nursing, the project became a patient-focused redesign effort encompassing both clinical and administrative affairs. The core ideas of the project approach included systems thinking, interactive planning and idealized design. This evaluation reports on the project's progress after six years.     

Effects of cadmium on the immune system of mice.

Chronic oral exposure of mice to Cd++ inhibits cell-mediated immunity of delayed type hypersensitivity induced by sheep red blood cells (SRBC). No effect was detected on humoral immune response to SRBC. Spleen cells derived from mice exposed to Cd++ showed in vitro enhanced response to T and B cell mitogens. These results demonstrate that Cd++ exposure alters the immune system of mice.     

Exploration of nano-surface chemistry for spectral analysis

The applications of nano-surface chemistry in the field of spectral analysis have attracted growing interest in recent years.In this article,we reviewed the applications of nanomaterials-based chemical reactions for spectral analysis,including the development in plasma-catalysis,surface-enhanced spectroscopy,separation and preconcentration,chemical vapor generation,labeling and signal amplification.Introduction of nano-surface chemistry to spectral analysis not only improves the sensitivity and selectivity,broadens the application range of spectral analysis,but also affords analytical community special characterization tools.     

Therapeutic neuroprotective agents for amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal chronic neurodegenerative disease whose hallmark is proteinaceous, ubiquitinated, cytoplasmic inclusions in motor neurons and surrounding cells. Multiple mechanisms proposed as responsible for ALS pathogenesis include dysfunction of protein degradation, glutamate excitotoxicity, mitochondrial dysfunction, apoptosis, oxidative stress, and inflammation. It is therefore essential to gain a better understanding of the underlying disease etiology and search for neuroprotective agents that might delay disease onset, slow progression, prolong survival, and ultimately reduce the burden of disease. Because riluzole, the only Food and Drug Administration (FDA)-approved treatment, prolongs the ALS patient’s life by only 3 months, new therapeutic agents are urgently needed. In this review, we focus on studies of various small pharmacological compounds targeting the proposed pathogenic mechanisms of ALS and discuss their impact on disease progression.