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Notes: At the present time scientific opinion has shifted to the view that man can, in certain circumstances and at certain places, modify at least local weather conditions in limited ways. Many believe that man can dissipate certain “cold” fogs in limited areas for short periods; that he can increase rainfall or snowfall by perhaps ten to fifteen percent in a local area in narrowly limited circumstances; that he can probably convert hail into less dangerous forms of precipitation, also in narrowly limited circumstances.1 Some experiments are being conducted to learn more about such phenomena as hurricanes and lightning. Man still needs to learn much more and to develop faster computers before he can begin to think of safely undertaking intentional modification on anything more than a local and highly selected basis. Nevertheless, it is clear that even the limited effects thus far produced do not stop at some predetermined boundary; both nationally and internationally attempts to modify weather can be expected to cause dislocations and friction.

Notes: Abstract Data were collected from eight cities on a wide range of cigarette and smoker characteristics for a sample of smokers. Of these, 564 smokers had had fires and were identified through fire department response to those fires, while the other 1,611 smokers had not had fires and were identified through a telephone sample survey of the communities. The characteristics analyzed included those that had shown evidence of a relationship to the risk of a cigarette-initiated fire, either in laboratory studies or in previous statistical analyses of fire experience. The smoker characteristics analyzed were household income, education, age, gender, and race. The cigarette characteristics analyzed were filter, tobacco column length, filter length, circumference, density, amount of tobacco, menthol, citrate, porosity, and pack type. In addition, a variable was used to control for the smoker's city. After controlling for all smoker characteristics and city, logistic regression modeling showed four cigarette characteristics to be significant: filter, filter length, porosity, and type of pack. Filter, filter length, and porosity all affect air intake, which, therefore, appears to be an important physical element in the combustion process associated with risk. Analysis limited to filtered cigarettes only showed the same characteristics to be significant, plus tobacco column length. Extension of the analysis to two-way interaction terms did not change any of the conclusions on which cigarette characteristics are important, but it did indicate that the role of pack type was different for men and women. Sensitivity analyses, shown in the appendix, supported the main conclusions that cigarette characteristics are significant after controlling for smoker characteristics and that the four specific cigarette characteristics—filter, filter length, porosity, and pack—are the ones that are significant. These analyses checked the impact of cluster sampling, sensitivity to missing data on smoker characteristics, and sensitivity to nonfire smoker cases with responses by people other than the smokers themselves. All this means that there are already cigarettes commercially available that exhibit a reduced propensity for ignition when one controls for smoker characteristics.

Notes: Abstract The Tertiary volcanism of Eastern Macedonia and Western Thrace (Greece) developed in association with the sedimentary basin which formed, from Eocene to Oligocene, along the southern margin of the Rhodope Massif. The volcanic products, ranging in composition from basaltic andesites to rhyolites, show an overall calc-alkaline orogenic affinity, while chemical characteristics identify different groups of rocks, probably reflecting minor differences among parent magmas. The observed evolution within any group of rocks is compatible with fractional crystallization processes acting on relatively shallow magma bodies. The Sr isotopic composition of rhyolitic member shows an initial87Sr/86Sr ratio comparable with that of basaltic andesites, reinforcing the hypothesis of a crystal/liquid line of descent. Geochemical and petrographic evidence, on the whole, suggests that the investigated orogenic association developed on an active continental margin characterized by a relatively thick crust, acting as a density filter for the basic magmas and facilitating their storage and fractionation within the crust itself. Minor contamination by interaction with host materials may also have occurred. Stratigraphic and K/Ar geochronological data indicate that the volcanic activity started in Upper Eocene and reached its maximum development in Upper Oligocene. From Lower Miocene, the volcanism shifted southward in the Central Aegean area and in part of Western Anatolia, coming to an end by Middle Miocene. The southward migration of the volcanic front has been interpreted as a consequence of the increase in the dipping of the Benioff zone, due to the decrease of penetrative strength after the main phase of continental collision.

Notes: Abstract New Rb/Sr and K/Ar data on minerals and whole-rocks from the metamorphic basement of Northeastern Sardinia are presented. A formation of augen gneiss of volcano-sedimentary origin yields a Rb/Sr whole-rock age of 441±33 m.y.; a Rb/Sr isochron age of 306±10 m.y. is found for the minerals separated from one of these samples. K/Ar measurements on micas also yield ages of 319–284 m.y. A banded migmatite which originated through a process of metamorphic differentiation was analysed by the Rb/Sr method. Six bands, treated as whole-rock samples, fit an isochron of 344±7 m.y. Biotite and plagioclase from one of these bands yield an isochron age of about 300 m.y. The radiometric results reported in this paper and all those previously published are discussed in order to investigate the tectono-metamorphic history of this important segment of the ancient Mediterranean basement. It is argued that in this area there is only indirect evidence of a “Caledonian” orogenic event (late orogenetic acidic magmatites emplaced 458-441 m.y. ago) while the main features of the metamorphic basement must be related to the Hercynian orogeny the climax of which can be fixed at about 340 m.y. The concordance of the ages of the separated minerals (310-300 m.y.) suggests that the metamorphic succession stayed above the specific critical temperatures for about 40 m.y., after which it was suddenly uplifted contemporaneous with the emplacement of the, essentially post-kinematic, Hercynian granitoids.

Notes: Abstract A cross-sectional study was performed to describe the prevalence of ocular abnormalities among six and seven year old children of Hispanic and Caucasian ancestry in Los Angeles County. Data were obtained from vision screenings of lower to middle income Hispanic and Caucasian children completed by the UCLA Mobile Eye Clinic at public neighborhood elementary schools and community centers between January and August of 1989, and January and March of 1990. Out of a total sample of 854 children, 64% were Hispanic; 36% were Caucasian; 51% were female and 49% were male. Ocular abnormalities observed were similar for both ethnic groups. Caucasians, however, showed non-significant, but consistently higher prevalences of most ocular abnormalities. Stronger associations between ethnicity and visual abnormalities were observed within the female subgroup. For example, hyperopia was found more commonly among female Caucasian children than among female Hispanic children (p〈0.01). This information can be used in planning for the eye care needs of communities with Caucasian and Hispanic components.

Notes: Abstract Knowledge of the epidemiology of eye disease among the elderly becomes increasingly important as our population ages. Leading causes of blindness in the elderly include age-related macular degeneration, open-angle glaucoma and cataract. Few studies have examined the prevalence of these blinding eye diseases among senior citizens. A retrospective review of vision screening examinations from 429 patients seen at the UCLA Mobile Eye Clinic in visits to a Jewish senior citizens' center was performed to examine the distribution of best recorded visual acuity and prevalence of eye disease in a group of ambulatory Jewish senior citizens. Best recorded visual acuity was ≥20/40 in the better eye for 83.9% of the patients. The prevalence of age-related macular degeneration was 20.7%, and increased with increasing age (p〈00005). The prevalence of open-angle glaucoma was 6.3%. The prevalence of senile cataract was 59.0% and increased with increasing age (p〈00005). Despite the limitations imposed by a retrospective review of charts, our study provides an indication of the prevalence of blinding eye disease and distribution of visual acuity among ambulatory Jewish senior citizens in southern California. Except for the high prevalence of senile cataract, the prevalence data derived from this study are similar to other epidemiologic studies of eye disease in the elderly.