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The distribution pattern of MCPA ([(4-chloro-o-tolyl)oxy] acetic acid) on leaf surfaces of three species was studied using the cathodoluminescence detection mode of a scanning electron microscope. On low-wax-content sugarbeet (Beta vulgarisL.) leaves MCPA concentrated in the depressions over the anticlinal cell walls when applied at high volumes (748 and 374 L/ha). At low volumes (23 L/ha), numerous small deposits of MCPA were randomly distributed over both anticlinal and periclinal walls. These distinct patterns were independent of herbicide concentration. Regardless of spray volumes, MCPA remaining on the waxy leaf surfaces of cabbage (Brassica oleraceaL.) coalesced into small thick deposits. Large spray drops from high application volumes shattered on impact with the stellate hairs of turkey mullein (Eremocarpus setigerusBenth.) resulting in some MCPA reaching the leaf surface. Spray drops from low application volumes did not shatter but lodged on the hairs with very little reaching the leaf surface.

X-ray fluorescence analysis (XFA) is a new method for the spatial localization and quantification of herbicide residue on leaf surfaces. The distribution pattern of propanil (3′,4′-dichloropropionanilide) on the surface of prune (Prunus domesticaL.) leaves sprayed to simulate drift is easily mapped using XFA. Residue distribution maps may be electronically enhanced. Enhancement does not qualitatively change the information content of the map when done with discretion.

A new empirical assessment of the functions A and B of Rossby-number similarity theory is made based on the Wangara data. Variations of these functions with stability, baroclinicity and time of day are discussed. It is found that B is dependent on stability in agreement with older data but contradicting the prediction of Csanady (1972). Coefficients expressing the variation of A and B with the two components of baroclinicity have been derived from the data, and these are claimed to be correct in regard to sign and approximately in regard to magnitude. Longer period time changes, represented by the diurnal cycle, are shown to result in systematic differences in A and B between the case of increasing stability and that of decreasing stability, for the same value of the stability parameter. The first attempt, to our knowledge, to present the actual functional form of the wind departure components (based on field data) is made. As the surface layer is approached in near-neutral conditions, the departure component in the direction of the surface wind assumes the expected logarithmic form.

Observations show that the angle between surface wind and isobar increases equatorward in low latitudes while the ratio of surface to geostrophic wind speed decreases. With the use of Southern Hemisphere winter fields of surface pressure and temperature over the oceans, and Rossby number similarity theory (including the effects of baroclinicity) in several different forms, the expected latitudinal variation of the angle and ratio has been computed. A check has also been made of mean ATEX and BOMEX data. It appear that the variations with latitude are probably mainly due to baroclinicity. With this factor taken into account, similarity theory fairly adequately explains the observations.

Distribution patterns of foliar applied herbicides can be studied by x-ray element mapping provided the herbicide contains an atom with an atomic number of 11 (sodium) or greater. The suitability of an herbicide for element mapping increases as the number of similar detectable atoms per molecule increases. Herbicides containing one detectable atom per molecule provide usable element maps at concentrations of 1.12 kg/ha and higher. Inaccurate element maps can result from: (1) Formulation components containing detectable atoms the same as those of the active ingredient. (2) Herbicide volatility during analysis due to reduced pressures and heating. (3) Specimen topography preventing x-ray detection at some locations on the plant surface. (4) Herbicide concentrations that are below the minimum detectable limit. If adequate precautions are followed in the use of x-ray element mapping, a wide range of uses exist in weed science.

Dr. Hess was Asked to prepare this paper for presentation at several of the conferences in connection with the NASDTEC-AAAS Study of Guidelines for Science and Mathematics in the Preparation Program of Elementary School Teachers in the winter and spring of 1961–62. His task was to stimulate thought by the conference participants on various issues related to the education of elementary school science and mathematics teachers. His thoughts may also stimulate science educators to consider research in the area of early experience in the learning of science.

Although high-styrene resins have become of great commercial importance during the past 5 years (approximately 25,000,000 pounds manufactured in 1949), comparatively little information on the polymerization processes or any systematic review of their properties can be found in the technical literature. The object of the present paper is to supply such information. A series of butadiene-styrene copolymers with charging ratios of 50/50, 40/60, 30/70, 20/80, and 10/90 was prepared. Polystyrene, prepared under the same conditions, was included as a control. Properties of the latexes and resins obtained, presented in a systematic manner, were found to be largely dependent on the monomer ratio employed in the polymerization. for the first time a coherent picture is presented of the entire plastic range of the styrene-butadiene resins. This should encourage the further development of this large and expanding field, which includes such applications as natural and synthetic rubber reinforcing, impact resistant compositions, protective coatings, and latex paints.

Rice [1] has shown that the noise output of an FM discriminator may be assumed to be the sum of two uncorrelated components, a Gaussian term and a click term (Poisson shot noise of impulses) for large carrier-to-noise ratios (CNR). In this paper the click process is introduced and the output noise is modeled again as the sum of a Gaussian term and shot-noise term that are in general correlated. The autocorrelation of the click process is derived and is shown to reduce to that of a Poisson process for large CNR. The cross correlation between the two components is derived, and the assumption that the two components become uncorrelated for large CNR is verified. The power spectrum of the Gaussian plus correlated click noise is compared to the exact power spectrum of the total output noise of an FM discriminator. Only the case with no modulation is analyzed.

'The study from which these findings were taken was conducted through the Stanford Center for Research and Development in Teaching by Robert D. Hess and Maria D. Tenezakis, with the assistance of Ian D. Smith, Rodney L. Brod, Henry T. Ingle, Judith B. Spellman, and Barbara G. Oppman. The fieldwork was done at Peter Burnett Junior High School in San Jose, California. The project was supported in part by funds from the U.S. Office of Education, Department of Health, Education and Welfare (Contract No. OEC-6-10-078, Project No. 5-0252-0407). The complete report: "The Computer as a Socializing Agent: Some Socioaffective Outcomes of CAI," Technical Report No. 13. Stanford, Calif.: Stanford Center for Research and Development in Teaching, 1970, (ED 044 942) is now available only from ERIC Document Reproduction Service, P.O. Drawer O, Bethesda, Md. 20014 (Microfiche, $0.65; hard copy, $6.58).

Early in the investigation of butadiene-styrene copolymers as synthetic rubbers, this laboratory became interested in copolymers containing much more styrene than any of the American or German synthetics. This interest was soon directed to the resinous copolymers obtained when the styrene content is increased beyond the range in which rubberlike properties are observed at room temperature. The exploratory work, therefore, involved preparation and evaluation of butadiene-styrene copolymers containing from 65 to 98 per cent styrene. No description of similar polymers has been found. Konrad and Ludwig claimed the improvement of rubberlike properties of butadiene-styrene copolymers by increasing the styrene content from the normal range to “between about 47.5 and about 70 per cent”. The claims and examples of this patent emphasize the improvement of rubberlike properties, such as tensile, elongation, and rebound, at high temperatures. It is well known in this country, however, that increase in styrene content beyond a certain point, perhaps 50–55 per cent, is accompanied by a loss of overall balance of rubber characteristics. Therefore, the copolymers at the upper end of the range described by Konrad and Ludwig have definite limitations for rubber uses—for example, low rebound, high brittle point, shortness, etc. In the writers' laboratory useful resins have been prepared from dienes and vinyl aryl hydrocarbons in the range 5 to 20 per cent diene and 80 to 95 per cent vinyl aryl hydrocarbon. This paper describes the properties and certain uses of one of these copolymers containing approximately 15 parts of butadiene and 85 parts of styrene. This material possesses a combination of physical and chemical properties which permit its use in several applications where cyclized natural or synthetic rubbers are commonly employed. Cyclized natural rubber has been described by Bruson, Endres, and Thies and Clifford. Cyclized synthetic rubbers were described recently by Endres. One product of this type is made from a special synthetic rubber. The new 15 butadiene—85 styrene copolymer is now identified as Pliolite S-3, since it may be used in many Pliolite applications, often with distinct advantages over either the natural or synthetic rubber derivatives.

The blood meal source for 4,957 engorged mosquitoes collected from 1964 through 1968 was determined by a capillary precipitin technique. Culex tarsalis and Aedes vexans comprised most of the specimens tested; other species tested included Aedes nigromaculis, Anopheles punctipennis, Culex quinquefasciatus, Culiseta inornata, and Psorophora signipennis. The predominant feeding of Aedes, Anopheles, Culiseta, and Psorophora was upon mammals, and of Culex quinquefasciatus upon birds. The C. tarsalis feeding pattern varied widely, and the proportion that had fed upon birds ranged from 42% in 1966 to 83% in 1965. An analysis of forage ratios provided an index of host preference of C. tarsalis in 1966. The data reported further substantiate the role of C. tarsalis as the principal vector of western equine encephalitis and St. Louis encephalities in the western United States.

Chemical reversibility of the nitrosyl chloride photodissociative laser is achieved by addition of a large excess of chlorine which also serves as an efficient buffer gas, and thereby eliminates the need for helium. Consideration is given to the prospect of utilizing this system as a means of converting solar radiation to monochromatic coherent emission.

Data from a recent experiment indicate that the height scale for wind in the planetary boundary layer is u*/F, where u*/F is the friction velocity and f the Coriolis parameter, rather than zi, the height of the convection-limiting inversion, or |L| the Obukhov length. None of the scales u*/f, zi, |L| appears to be appropriate for temperature except in slight-to-moderate stability where again u*/f appears to be the most suitable. The data do not support either Businger's expression which gives the depth of the idealized thermal boundary layer, depending on surface heat flux and rate of temperature change, or Tennekes' expression for bulk temperature difference across the boundary layer in free convection, based on the ratio of −L to the roughness length z0.

Summary A brief review is given of the history and epidemiology of malaria in the Philippines, and of control practices up to the present day. The Six-Year (1953–1958) Philippine-American Program for Malaria Control in the Philippines has for its objective the reduction of malaria to an insignificant level by annual spraying of all houses in malarious areas with DDT for at least 3 consecutive years, and thereafter spot-spraying of houses as local conditions demand. Concomitantly there is being developed a long-range program which consists of more permanent measures. Anti-malaria drugs are used as a supplementary relief measure. The total number of houses to be sprayed is about one million, with over four million house-sprayings to be carried out during the six year period. During the first season's operations (1953) a total of 215,000 houses were sprayed and 85,000 people received treatment for malaria. During 1954 the program has been expanded to a nationwide spraying of one million houses, which will bring malaria protection to 5 million people.

A new type of FM demodulator, the Frequency Locked Loop (FLL) is presented. The concept employed in this class of circuits is shown to be applicable in two forms. The first form is realized at the carrier, or IF frequency, to provide an FM detector that has the properties of not requiring a limiter preceding it and also of having a threshold superior to a normal FM discriminator limiter combination. The second form of the FLL is realized at baseband. This form may be added to any existing FM receiver to provide threshold extension properties to the original receiver. In addition to discussing both versions of this new circuit arguments as to the click suppression and threshold extension properties of the circuit are presented. Detailed experimental comparisons of the new circuit with a conventional FM discriminator are made. A comparison is also drawn between the theoretically possible threshold extension of an FLL and that actually obtained with a baseband version of the FLL.

The microwave spectrum of nitroethylene (CH 2 CHNO 2 ) and one deuterated species (CH 2 CDNO 2 ) has been investigated in the region from 8 to 26 Gc/sec. High resolution spectra have been run to find the nitrogen hyperfine splittings. A numerical analysis of the spectra yielded the following rotational and quadrupole coupling constants of the normal species in the ground vibrational state: A = 11 811.757 ± 0.010 Mc/sec, B = 4 680.7851 ± 0.0021 Mc/sec, C = 3 353.7697 ± 0.0025 Mc/sec, χ aa = −883 ± 49 kc/sec, χ bb = 14 ± 24 kc/sec, and χ cc = 869 ± 49 kc/sec. The ground-state rotational constants for the deuterated molecule were found to be A = 11 042.68 ± 0.04 Mc/sec, B = 4 658.475 ± 0.015 Mc/sec, and C = 3 278.069 ± 0.015 Mc/sec. The dipole moment of 3.70 ± 0.03 D was determined from Stark displacements. Relative intensity measurements of satellites arising from excited states of the torsional motion of the nitro-group led to an estimate of 100 ± 20 cm −1 for the torsional transition frequency. Finally, it is shown that nitroethylene has a planar molecular structure.

Summary An investigation was made of the entomological aspects of the 1959 epidemic and epizootic of EE in New Jersey. Extremely heavy rainfall during July resulted in a record production of mosquitoes, the three most abundant species being Aedes sollicitans, Aedes vexans, and Culiseta melanura. Change in the average wind direction from southwest to south probably increased the contact of salt marsh mosquitoes with humans in the epidemic area. A serum survey of 22 farm chicken flocks indicated that about ⅔ had HAI antibodies to EE and that high rates of EE transmission occurred in both the coastal and inland areas of southern New Jersey. About ⅓ of 92 wild bird sera also had HAI antibodies to EE. All available information supports the hypothesis that: (1) The swamp mosquito, C. melanura, served as the primary sylvan vector which carried EE virus from enzootic swamp foci to peridomestic wild and domestic avian reservoir hosts in both the epidemic (coastal) and episootic (inland) areas; (2) A. sollicitans served as the primary epidemic vector in the coastal area where most of the human cases occurred, obtaining its infection from peridomestic avian reservoir hosts (including chickens) and subsequently transmitting the infection to man; (3) A. vexans served as the primary epizootic vector in the inland area of the equine outbreak, obtaining its infection from peridomestic avian hosts and subeequently transmitting the infection to horses; and (4) A. vexans may also have served as a vector for occasional human cases that occurred in the inland area.

IN THE VARIOUS recent discussions concerning i techniques for intr a-individual assessment, Q-me thodology has received more attention than any other single type of analysis. William Step he nsonhas been instrumental in bringing this method to the fore. His book on the subject gives an account of his views on the premises, promise and utilization of Q-me thodology (6). Among the reviews of Stephenson's book, Cron bach and Gleser's discussion seems the most defin itive in both its positive and negative evaluations (1). One phase of Q-technique as advanced by Ste phenson that these reviewers find particularly in appropriate is the use of a forced distribution of the the items, i. e. , requiring that a prede te r mined number of items be placed in each cell of the sort. They believe that this procedure negates the possib ly advantageous use of analysis of variance. Fur thermore, they point out that the F-testis based on the assumption that values in each cell are random ly sampled from an infinite population and that this assumption does not hold in the forced distribution. Cronbach and Gleser also object to the use of the near-normal distribution as discarding information about differences in scatter, although noting that it ensures variance in responses and e lim inates re sponse sets. Stephenson's principal argument for the use of the forced Q-sort centers around the importance of requiring the ordering of subjective data into a semi-normal distribution. S t e p h e nson c o n t e d s that the means are of little significance while var iations are extremely useful. Cronbach and Gle ser's remarks that the forced distribution insures variance in response and eliminates response sets also argue favorably for this type of administration. However, Stephenson appears agreeable to the use of non-forced distribution in suitable situations. The loss of differences in scatter as pointed out by Cronbach and Gleser may not be i m p o r tant in all research designs, yet it is a factor to consider in any use of the Q-sort. In relation to the treatment of data, their argument is to discard the forced sort since it negates the use of the analysis of var iance which is potentially advantageous.

The four species of blood-sucking mosquito found in Hawaii (Culex quinquefasciatus, Aedes albopictus, Aedes aegypti, and Aedes vexans nocturnus) were collected from November 1965 through May 1968, and the blood-meals identified to establish host range. C. quinquefasciatus fed mostly on birds but also fed on a wide range of mammals. A. v. nocturnus fed only on mammals, with horses and cows being the predominant hosts. A. albopictus and A. aegypti fed almost exclusively on mammals, with A. aegypti feeding on man more than on any other host. The host-feeding patterns of these four mosquitoes in Hawaii indicate that they might be ecologically capable of serving as enzootic vectors of certain arboviruses.

Es wird gezeigt, das ein Einflus der schwefligen Saure, der Zeit und der Garung auf die Aktivitat von Polyphenoloxydasen besteht.

Ein Vergleich der Methoden von Weinmann u. Deibner zur Bestimmung der gesamten schwefligen Saure zeigte, das die letzte Methode zu exakteren Werten fuhrt,vor allem dadurch bedingt, das das uberdestillierte Schwefeldioxyd in einer sauren gekuhlten Vorlage aufgefangen wird. Ein Nachteil der Methode ist, das bei der Titration der Vorlage mit Jodlosung der pH-Wert mehrfach geandert werden mus. Es gelang uns, diesen Mangel ohne Einbuse an Analysengenauigkeit dadurch zu beseitigen, das wir als Auffanglosung ein Puffergemisch (pH 3,5) benutzen und nicht in saurem, sondern in schwach alkalischem Milieu mit Jodlosung titrieren. In dieser Form kann das Verfahren zur Bestimmung der gesamten schwefligen Saure im Wein empfohlen werden.

Summary An analysis made of the weather conditions associated with human outbreaks of eastern encephalitis in the United States revealed that the major outbreaks occurred in Massachusetts and New Jersey, and that a weather pattern of excessive rainfall during the summer of the outbreaks and the preceding autumn was consistently associated with the disease outbreaks. The only other state which reported four or more human cases in a single year was Louisiana with ten reported cases in 1947, during which no specific weather pattern was apparent. Equine outbreaks of eastern encephalitis in Massachusetts and New Jersey coincided with human outbreaks and were, therefore, associated with the same weather pattern. The relationship between the amount of precipitation and the number of equine cases was less consistent in Delaware and Maryland, and only occasional associations were noted between excessive amounts of rainfall and equine outbreaks in Florida, Louisiana, and Texas. It seems reasonable that weather conditions might be used to predict human and equine outbreaks of eastern encephalitis in the northeastern United States. In the Taunton, Massachusetts, area there would appear to be danger of an eastern encephalitis outbreak during any year when 26 inches or more of rainfall had accumulated during the previous August through October and the current June and July. In states south of New Jersey, the available data are not adequate to provide a basis for predicting epidemics or epizootics.

The present study reports on experimental investigations about the phase velocity diagrams of Alfven waves in the anisotropic solid-state plasma of bismuth. Alfven-wave transmission at 34 GHz and 4.2 K has been observed, using an interference technique of high sensitivity. The experimental results are in good agreement with a theoretical model given by Buchsbaum, which makes only use of the anisotropic mass tensor of bismuth.

The chain reaction between hydrogen and fluorine mixed with helium has been successfully employed to generate laser emission from HF. Chemical reaction was initiated by flash photolysis of the reagents premixed at room temperature. Evidence for participation of the ``hot'' reaction, H ·+F2→HF*+F ·, in the laser pumping mechanism is presented. Approximately 7% of the laser radiation from this system is at wavelengths longer than 3.04 μ indicating that the large exothermicity of the ``hot'' reaction is not temporarily stored as population inversion between high vibrational levels of newly formed HF. Power and energy outputs up to 18 W/cc and 0.5 mJ/cc have been measured from dilute mixtures (40:1) at total pressures of 130 torr. Small‐signal gains of 3%/cm, chemical efficiencies of ∼1%, and pulses having durations up to 140 μsec were observed. Computer calculations of reaction times are in good agreement with the pulse durations observed for a variety of experimental conditions.

SIGNIFICANT DIFFERENCES in mental test performance be tween high and low socio-economic populations in the United States and Europe are well documented in the literature and consistently show a superiority in test scores of high-status samples. While this evi dence for differential test performance by socio-economic level is in disputable, there have been traditional disagreements over the conclu sions that reasonably may be drawn from these research reports. Pro ponents may be found for each of these three points of view: ( 1 ) the superior test performance of high socio-economic groups represents a genetic superiority in intelligence; (2) the superior performance of the high-status samples indicates a true difference in intelligence a difference which results from environmental rather than genetic fac tors; and (3) the differential performance of high and low-status levels arises from cultural factors within the testing instruments and testing situation themselves and do not necessarily reflect either gen etic or environmental differences in intelligence between groups. The implications that follow from these separate points of view are sharply divergent in their significance for educational practice and curriculum development. Allison Davis and his associates have recently advanced the last of the conclusions mentioned abovel. Davis argues that behavior requis ite for successful achievement on intelligence test items is, to a ve r y great extent, culturally learned, and that the cultural background of the high-status child, as compared with that of a low-status child, is more adequate preparation for appropriate response to a test which is highly saturated with "middle-class" symbols, problems, vocabulary, and objects. This situation, according to Davis, creates a bias in favor of high-status pupils which leads to higher test scores, on the average, for the pupil from high socio-economic levels. When cultural dissimilarities exist between samples under investi gation, it follows from Davis' position that relative mental ability of the groups can be evaluated only if the test items represent cultural experi ence and training equally familiar, on the average, to the groups i n volved. Davis and Eells have conducted intensive research on the problem of cultural bias in several standard group intelligence tests. While their

In this paper a model for a carrier plus narrowband noise is presented, and with its aid the expected number of cycle slipping events per second for a first-order phase-locked loop (PLL) driven by a narrowband noise corrupted carrier, both with and without a limiter, is determined. Experimental data are presented which indicate the extreme accuracy of the results obtained with the use of this model. The noise model, which is based on the hypothesis that steps of \pm2\pi in phase exist when a carrier is added to narrowband noise, yields not only computational simplicity in calculating the expected number of cycle slipping events per second in a PLL, but also a good deal of insight into the basic threshold improvement mechanism of the PLL. In particular it is shown that a cycle slipping event, or equivalently a PLL output "click" occurs not when the PLL "loses lock," but rather when it tracks a step of \pm2\pi appearing at its input.

— Recent studies of the effects of molecular structure and reaction environment on the mechanism of primary photochemical processes involving transfer and conversion of electronic energy in relatively ‘simple’ organic molecules are presented and discussed. A quantitative i.r. spectroscopic method for studying intramolecular and intermolecular photoprocesses of u.v. irradiated substrates dispersed in solid alkali halide matrices at room temperature is described. Current data for the substrates ortho-nitrobenzaldehyde, anthracene and benzophenonebenzhydrol are presented. A series of ‘model’ ketones containing cyclopropyl groups have been synthesized and while their absorption spectra are similar, the efficiency of vapor-phase photodissociation into radicals is shown to be strongly dependent on molecular structure. Butyrophenone and a series of ring substituted derivatives have been photolyzed in the liquid phase using the quantum yield of the photoelimination of ethylene (Type II split) as a “probe” to determine the effect of substituents on the internal H atom abstracting power of the excited carbonyl chromophore. Φc2H4 is very sensitive to ring substitution, dropping from 0.24 in butyrophenone to 0.20, 0.058 and 0.00 in the p-CH3, p-OCH3 and p-NH2 derivatives respectively, and to 0.00 in both ortho and para hydroxy derivatives. This effect is correlated with their absorption spectra in terms of the lowest states of these alkyl aryl ketones being 3(π, π*) rather than 3(π, π*) in character. While several ‘classic’ photochemical reactions, unimolecular and bimolecular, proceed efficiently in solid KBr matrices giving the same product as in liquid systems, the ‘model’ cyclopropyl compounds and the alkyl aryl ketones did not undergo their usual intramolecular processes. Implications of this molecular environment effect are pointed out.