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The procedure described in this paper, when applied to data collected in a pilot study, enables determination of an efficient sampling intensity for studying beta diversity in a plant community. A statistic, Sβ, is introduced as a measure of beta diversity. The method can be applied where (1) many species are to be observed, (2) quadrat sampling is to be used, and (3) presence:absence data are desired.

An analysis of the architecture, settlement distribution, and geography of the Chimu city of Chan Chan and specific attendant sites makes it possible to discuss the administration of land, water, and labor resources and the production and distribution of goods as primary socio-economic factors in the maintenance of a hierarchical social organization. U-shaped structures, called audiencias, which are present both in urban and rural settings, are crucial to an interpretation of the Chimu administration of production, distribution, and storage of goods. Given the Peruvian coastal environment, this interpretation provides an insight into the structure of urban-rural relations during the Chimu occupation of the Moche Valley.

Wet air oxidation is a process in which organic materials in the aqueous phase are oxidized by air at temperatures between 300°F and 600°F and pressures of 1000-1800 psia. To improve our understanding of the process, its kinetics were studied using a propionic acid solution to simplify both analysis and rate measurements. The aim of the research was to define the regime where the reaction rate is kinetically controlled, to develop a model for the reaction rate and to interpret the model in terms of mechanism. Oxidation appears to proceed homogeneously in the aqueous phase and is probably kinetically controlled between 450° and 550°F. The oxidation appears to take place via two principal routes. Approximately half the propionic acid is oxidized completely to carbon dioxide while the oxidation of the remainder apparently proceeds via acetaldehyde as an intermediate to acetic acid. Acetic acid oxidizes only at a very low rate. A power law rate expression was developed which adequately described the oxidation of propionic acid solutions.

Dams and reservoirs are often partially justified on the basis of an intangible benefit related to the property value changes that they allegedly induce. This assumption is tested by using the G. Ross Lord Dam and parkland on the west Don River in Toronto. The project had virtually no impact on residential property values in the summer of 1972 while the dam was under construction. The magnitude of the social benefit related to the residential land value changes induced by such a project is considered.

IN PREVIOUS electron micrographs of the virus of chronic respiratory disease in chickens (Tucker strain) it was demonstrated by Reagan et al. (1951) that this strain contained virus-like filaments which had an average width of 53 millimicrons. The morphological characteristics of this strain of chronic respiratory disease (CRD) of chickens appeared to be similar in size and shape to the causative agent of infectious sinusitis of turkeys. The present studies were undertaken to determine whether the causative agents of different strains of chronic respiratory disease differ morphologically and whether more than one agent could be detected by electron microscopy. METHODS AND MATERIALS The four strains of CRD were obtained from the following men: Dr. Henry Van Roekel of the Agricultural Experiment Station, Amherst, Massachusetts, (strains A and B); Dr. Harold E. Moses of the Agricultural Experiment Station, Lafayette, Indiana, (strain No. B706) * ; and Dr. James A. Bivins of the New …

Thorne Cave is a site in Cliff Creek Canyon, north-eastern Utah. Between 5000 and 2000 B.C. alluvial fill in the canyon reached the level of Thorne Cave and formed its floor. At this time, and intermittently for perhaps the next 200 years, peoples with a Desert Archaic cultural tradition camped on a dune near the cave mouth while the canyon and the cave continued to fill. Stratified camp debris was washed into the cave, and alluvium accumulated well above the cave brow, leaving a dead space in the dome area of the cave roof. Dissection of canyon alluvium later re-exposed Thorne Cave and washed away much of the evidence of human occupation. Radiocarbon-dated charcoal indicates that the site was occupied as early as 4230±250 years B.P. Materials recovered from Thorne Cave include redeposited charcoal and food-bone scrap; projectile points, small choppers and scrapers, manos, and grinding slabs; bone awls, needles, a pendant, a flaking tool, and a scapula seed-header; and impressions of twined basketry.

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Ninety-six Macaca mulatta were exposed to aerosol particles containing Pasteurella tularensis. Four different aerosols were employed that contained particle size distributions with median diameters of 2.1, 7.5, 12.5, or 24.0 μm. Size distributions were calculated only for those particles observed by phase microscope to contain organisms. Animals exposed to particles whose median diameters were either 2.1 or 7.5 μm were all infected and showed extensive infection of the lower respiratory tract, evidenced by large patches of consolidation with many necrotic foci on the surface. Death occurred in these animals 4 to 8 days after exposure. Monkeys exposed to 12.5- or 24.0-μm median diameter particles presented involvement of the cervical and mandibular lymph nodes, evidenced by swelling and abscess formation. Thirty-eight of the 45 animals in this group were infected. Those animals succumbing to the disease died from 8 to 21 days after exposure. The respiratory LD 50 values increased from 14 to 4,447 cells as the median diameter was raised from 2.1 to 24.0 μm.

Wet air oxidation is a process for the oxidation of organic matter dissolved or suspended in water. It operates from 300 to 600 F, usually at pressures of 1000 to 1800 psia. The process is not well understood. This paper reports a kinetic study using propionic and butyric acids. Our research has been directed towards three objectives: identification of the kinetic-control regime; development of a rate equation model, and investigation of the oxidation mechanism. Most of the work was performed using propionic acid. Results with this compound appears to be confirmed by studies using butyric acid. With vigorous agitation, the reaction is kinetically controlled below 550°F and is homogeneous in the aqueous phase. Oxygen attack at the α carbon is suggested by the data. This would account for the high yields of acetic acid. This slowly oxidized acid forms via acetaldehyde. A power law rate expression was developed for the oxidation of propionic acid. Work with butyric acid supports the propionic acid results.

1. A method is described for the differentiation and determination of as little as 0.2mug. of vitamins D(2) and D(3) by gas-liquid chromatography. 2. The vitamins are converted by treatment with antimony trichloride into isovitamins D(2) and D(3), which show single, separate peaks on gas-liquid chromatography, unlike the unmodified vitamins, which give twin peaks due to the formation of pyro and isopyro derivatives. 3. Since isovitamins D(2) and D(3) remain together in all steps of the procedure except during gas-liquid chromatography, one may be used as an internal standard for the other. 4. The use of an internal standard reduces the importance of loss during sample preparation and increases precision. 5. The application of the method to biological materials is demonstrated.

SYNOPSIS Owing to extensive discussion of lake levels and the causes controlling them, the precipitation data of the Weather Bureau and the Canadian Meteorological Service for the drainage basin of the Great Lakes have been examined with care. From 1875 trustworthy determinations are possible. The precipitation averages about 32 inches per year, and in general increases from north to south. As a rule the stations considerably above the levels of the lake surfaces indicate more precipitation than those close to the lake levels. The lake surfaces probably receive about as great precipitation as do stations at or near the shore, the deficiency in catch in gages exposed on islands or peninsulas being considered as due to increased Rind effect. The precipitation was unusually heavy, on the average, from 1875 to 1885, and the period 1875 to 1899 shows more precipitation at almost every station than the period 1900 to 1924. However, there were groups of a few successive years with scanty precipitation b...

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Neither Canada nor the United States attach much importance to the International Joint Commission (IJC) judging by the size of staffs and annual budgets. The Commission has been restricted to a relatively minor number of functions in the Great Lakes-St. Lawrence. It has investigated: the degree and causes of water and air quality deterioration; the effects of hydroelectric and navigation projects on water levels; the impacts of water-level fluctuations; and the feasibility of a deep waterway from the St. Lawrence to the Hudson River. Projects approved by the Commission have produced less than might be expected through no fault of the Commission. The Great Lakes Fishery Commission has promoted little international management. Budgetary limitations restrict its lamprey control program; institutional limitations restrict its ability to deal effectively with fishery problems. Commission responsibilities are limited to coordination and advisory functions. Since Canada and the United States have not chosen to refer most aspects of river basin management to international bodies, an institutional void exists in the Great Lakes Basin to consider these questions on a continuous basis. There is a need for expanded international cooperation.

This paper describes how a certain kind of table may be used to check the syntax of a string of symbols. In its simplest form, a symbol-state table closely resembles a finite state machine, and requires a large amount of space, often to store duplicated information. By means of the subroutine principle such duplication may be avoided, and recursive use of the table achieved, making possible the checking of recursive structures. When syntax checking is not the only aim, or when checking needs to be performed which is beyond the scope of the table, sections of program coding may be called from the table. Applications have included the writing in FORTRAN of a syntax checker for FORTRAN, and the automatic proof reading of dictionary entries.

The axodendritic response evoked by electrical stimulation of the cortical surface is diminished by intrapial injection of cholinergic agents. This effect is probably muscarinic in nature since it is blocked by atropine, and since administration of nicotine over a wide dose range does not diminish the axodendritic response. The diminution of the dendritic psp is not due to activation of inhibitory synapses because d -tubocurarine, strychnine and tetanus toxin, which are known blockers of inhibitory synaptic activity in spinal cord and brain, do not prevent the depressant effect of cholinergic agents. Since subcortical effects have been excluded by drug administration directly into the pial arteries, it is concluded that the muscarinic receptors involved are located within the cerebral cortex.

The addition of 2-diazopropane to methyl acrylate and its methyl-substituted analogues normally (i.e., when electronic effects are dominant) gives methyl 1-pyrazoline-3-carboxylates, of which those bearing a hydrogen atom at C(3) tautomerise readily to the Δ2-isomers. The orientation of addition is reversed in the reactions of methyl 3-methylbut-2-enoate with 2-diazopropane and diazoethane. Methyl 4,4-dimethylpent-2-enoate undergoes reverse addition with 2-diazopropane, but not with diazoethane or diazomethane. The reversals are attributed to the presence of unfavourable eclipsing interactions in the transition state for normal addition.

The distribution of lignin has been studied in tracheids and ray cells of normal and compression wood of tamarack [Larix laricina (Du Roi) K. Koch]. The three layers in the secondary wall of normal wood tracheids are lignified to approximately the same extent, and previous evidence that the S 3 layer should contain a higher proportion of lignin than the other regions has not been confirmed. The lignin follows closely the orientation of the cellulose microfibrils in all three layers. Compared to the tracheids, the ray cells contain a denser network of lignin in their secondary wall. Only a small proportion of the total lignin in compression wood tracheids is present in the compound middle lamella. The thick S 1 layer is only slightly lignified; the orientation of the lignin in this region is that of the transversely oriented, lamellated microfibrils. The outer portion of S 2 consists largely of lignin but also contains lamellae of cellulose microfibrils which probably have the same helical orientation as the microfibrils in the inner part of S 2. The latter region, which contains the helical cavities, consists of lamellae of cellulose microfibrils which are uniformly encrusted with lignin. The ray cells in compression wood appear to be lignified to the same extent as in normal wood. Transverse sections of the cells reveal a lateral orientation of the lignin. The orientation of the cellulose microfibrils in the S 2 layer of the first-formed springwood tracheids of compression wood is the same as in the cells which are formed later. It is suggested that for ease of reference, the outer, lignin-rich layer in compression wood tracheids be referred to as the S 2(L) layer.

An experiment based on a two-by-two factorial design was conducted to test hypotheses involving the relationship of four supervisory styles to aggressive feelings and actions of subordinates. The supervisory styles were arrayed on two continuums: the close versus general and the punitive versus non-punitive. Close as compared with general supervision produced significant increases in aggressive feelings toward the supervisor and in indirect aggression toward the supervisor through lowered productivity, an insignificant increase in verbal aggression toward the supervisor, and an increase of borderline significance in aggressive feelings toward co-workers. Punitive as compared with non-punitive supervision produced significant increases in indirect aggression through lowered productivity and in verbal aggression, but no significant increases in aggression toward co-workers. The relationship between close supervision and aggresive feelings appears to be mediated by the self-esteem of the subordinate; an incr...

This paper deals with floodplain land use management approaches for urban flood damage control. These alternatives are important because traditional flood control projects, such as levees, channel improvements, and reservoirs, are not always capable of correcting the physical and economic conditions that give rise to flood damage. It is expected that land use management will complement engineering works and lead to more effective use and development of floodplain lands. The paper presents a computational technique for evaluating alternative land use assignments based upon the economic value a community gains from its land. A linear programing model is developed that identifies economically efficient combinations of (1) spatial and temporal planning of urban land use, (2) site elevation through landfill, and (3) flood proofing of buildings.