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Insect repellents are widely used as the first line of defense against mosquito bites and transmission of disease-causing agents. However, the cost of daily applications of even the most affordable and the gold standard of insect repellents, DEET, is still high for low-income populations where repellents are needed the most. An Indian clove-based homemade recipe has been presented as a panacea. We analyzed this homemade repellent and confirmed by behavioral measurements and odorant receptor responses that eugenol is the active ingredient in this formulation. Prepared as advertised, this homemade repellent is ineffective, whereas 5x more concentrated extracts from the brand most enriched in eugenol showed moderate repellency activity against Culex quinquefasciatus and Aedes aegypti. DEET showed higher performance when compared to the 5x concentrated formulation and is available in the same market at a lower price than the cost of the ingredients to prepare the homemade formulation. [ABSTRACT FROM AUTHOR]

Focuses on a study that investigated epitaxial cobalt gallium and textured cobalt arsenide contacts on gallium[sub1-x]aluminim[subx]arsenide fabricated by molecular-beam epitaxy. Details of the experiment; Results and discussion; Electrical evaluation; Conclusions.

Blood- and sugar feeding of female mosquitoes has been frequently observed in the laboratory and in the field, but only sugar feeding of males has been reported. Here, we describe for the first time that Culex quinquefasciatus males feed on blood as well. Blood feeding easily happened on a blood-soaked cotton roll and, to a lesser extent, through a thin artificial layer. Mating history of a male specimen does not affect his blood feeding behavior. Male mosquitoes feed on blood even when they have a readily available sugar source. Nevertheless, feeding on blood reduces the survival rate of males to just a few days, as compared to more than a month for mosquitoes fed only on sugar. Comparing survival of male mosquitoes fed on blood only, sugar only, and a combination of both clearly demonstrated that mortality is not affected by malnutrition (reduced sugar levels), but rather due to ingested blood. On average male mosquitoes ingested ca. 0.5µl of blood, i.e., about 10% of the amount of blood ingested by an engorged female. Although this unexpected observation of blood feeding in the laboratory by male mosquitoes is interesting, structural impairment prevents male feeding on vertebrate blood. In agreement with the literature, male and female proboscises and stylets were in general of similar size, but male mandibles were significantly shorter than female counterparts, thus explaining their inability to pierce through skin layers. [ABSTRACT FROM AUTHOR]

Spasticity is evident in both humans and animals following spinal cord injury (SCI) and can contribute to significant functional limitation and disruption in quality of life of patients with this disorder. This mini-review describes a number of preclinical and clinical studies that promise to improve outcomes for, especially in terms of spasticity and hyper-reflexia, patients with SCI. A gold standard for the quantification of spasticity has proved elusive, but the combination of H-reflex frequency dependent depression and a novel stretch reflex (SR) windup protocol have the potential to provide new insights. As the pathophysiology of hyper-reflexia and spasticity continue to be investigated, the documented onset in the animal model of SCI provides critical time points for further study into these complex mechanisms. The positive effects of a passive exercise protocol and several potential pharmacological interventions are reviewed as well as a novel potential mechanism of action. Further work is needed to determine additional mechanisms that are involved in SCI, and how to optimize multiple therapies to overcome some of the deficits induced by SCI. [ABSTRACT FROM AUTHOR]

The article focuses on the study of emotional instability and intelligence of women in the penal institutions of North Carolina. It is an attempt to measure, by group methods, the mental ability and some temperamental traits of white delinquent girls in the penal institutions of North Carolina. Results thus obtained will be studied both with respect to themselves as well as in their relation to certain other factors in the home life and present status of the subjects concerned. The major findings of the study are: 1. Physically, these delinquents are not unlike non-delinquents. 2. Venereal disease is quite prevalent among the groups of delinquents used for this study. 3. More girls are confined in these penal institutions for sex offenses than for any other type of offense. The majority of these subjects were confined before 25 years of age. The present study would lead one to the further generalization, that; heredity, maturity, environmental circumstances, and physical and mental abnormalities are all important factors for consideration in relation to crime. However, each of these should be viewed as a contributing factor, working in relation to each other as well as with other factors, and not as actual isolated causal factors.

This article discusses on the mental development of a child from birth to maturity. The normative approach to the study of child growth and development is still used extensively,but there also seems to be a growing realization that the factors that cause or influence particular outcomes must be studied and assessed. New technics and methods of research are being developed and the relatively intangible aspects of growth explored. The need for new evaluative procedures, including the statistical, is becoming increasingly apparent as the problem of patterns of development is commanding greater and greater attention. At Antioch College the Samuel S. Fels Research Institute is following 130 children from conception through adolescence. The work of the Yale Clinic of Child Development is published in a series of notable articles and books. A recent publication summarizes the outcomes of the Third Harvard Growth Study. The Fourth Harvard Growth Study was begun by Stuart and his associates in 1930 and deals with children from birth on. The Berkeley Growth Study, which also deals with children from birth on, is summarized by Jones and Bayley; they include a helpful bibliography of thirty-seven titles. The possible effects of using subjects of different backgrounds of education and experience are not generally recognized and conclusions from studies must be tentative.

This article presents a study of attitudes of college students. The present study is an outgrowth of an earlier study in which the author participated. In this study, the attitude scale developed by G.B. Vetter was given to college students from the different classes at North Carolina State College. From the comparisons of the attitudes of the students from the different classes it was found that each succeeding class was more liberal and consistent in its attitudes over the preceding class. In the present study, a modification of Vetter's "Social and Political Attitudes Test" was used. Five gradations of response were presented for each test item ranging from quite a reactionary to an extremely liberal viewpoint. The test was then given a trial experience with members of the faculty from the departments of history, sociology, psychology and education. The results reveal higher scores for the seniors, which indicates that they possess a more liberal attitude. These scores indicate further that students from the larger towns are more liberal, although there is a tendency for this difference to decrease with four years of college training.

The article presents information on a study regarding the amount and nature of anti-African American prejudice existing among students at North Carolina State College. Some subsidiary problems encountered are a comparison of the racial attitudes of the students from the various college classes, and a comparison of the racial attitudes of the students coming from a rural background with those from an urban. A list of 35 statements taken, with slight modifications, from the Social Science Research Council's questionnaire on racial attitudes was given to 163 students in psychology and sociology classes at North Carolina State College. Each student was given a list of the statements and instructed to mark each statement true or false according to his strongest inclination. There is no consistent pattern of attitude that distinguishes one class from another, although on most statements the seniors are more generous or lenient toward the African American than are the lower classes. The authors note a considerable amount of anti-African American prejudice among the students of North Carolina State College. The nature of the prejudice is chiefly social and political.

The article presents a study of the emotional characteristics of women prisoners. In this study 138 of the inmates of three penal institutions for white women in North Carolina were used as subjects. The chronological age range of these prisoners was from 15 to 30 years, and each case had committed some offense serious enough to be classified by the court as a misdemeanor. Thus, every girl in these institutions between 15 and 30 years of age who had committed a misdemeanor, save some few who were paroled during this study and several others not available due to the prison's program, was used in this study. The girls, with the exception of one Italian girl, were all native-born Americans. The chief offenses committed by these girls were: sex, 51%; delinquency, 18.1%; larceny, 5%; and robbery, 3.6%. The Thurstone and Thurstone Neurotic Inventory, in the form of a questionnaire, was used for the measurement of emotional instability of these 138 subjects. Those questions which, from former results, showed little or no differentiation were omitted. Leaving these out would affect the reliability of the test and scores very slightly, if any.

The article analyses the relative influence of intelligence and socio-cultural status upon the information possessed by first-grade children. The drawing mental age and the socio-cultural status were found for these 156 first-grade subjects. These subjects were then paired first with respect to mental age, chronological age, and sex, but with a significant differential score for each pair on the socio-cultural scale. Again the subjects were paired with respect to socio-cultural status, chronological age, and sex, but with a significant differential score for each member of each pair in mental age. Thirty-three pairs of subjects were thus obtained. Certainly, one can concluded that these tests measure these elements in part, and, in so far as they measure these factors, one would conclude that information of first-grade children is related to each of these but more closely related to socio-cultural status. The relationship between information and socio-cultural status is here found to be from two to three times as great as that between drawing mental age and information.

The article presents a study of the opinions of college students. Opinion deals with that which is probable and subject to change. It rests in the main upon the sentiment of the individual. It has been defined as the verbal expression of an attitude; and an attitude as the sum total of man's inclinations and feelings, prejudice or bias, preconceived notions, fears, ideas, threats, and convictions about any specific topic. Opinion reflects the early environment of the students, together with a certain amount of reading with deliberations. A review of all the literature pertaining to opinions or beliefs would not be appropriate to a scientific attempt to investigate and analyze the beliefs of college students. Hence only those investigations that are of scientific in nature, dealing specifically with the measurement and analysis of beliefs of students, are included in this study. Case studies, historical treatises, personality and character trait studies as well as specialized studies of the attitudes of groups other than students are all of interest and value but not pertinent to this study.

The interface between the (001) surface of GaAs and a CoGa layer grown by molecular beam epitaxy has been characterized using transmission electron microscopy in plan view and cross-sectional view. The interface is found to consist primarily of a network of edge dislocations with Burgers vectors a[100] and a[010] (a being the lattice parameter of the CoGa). The occurrence of these Burgers vectors indicates that these misfit dislocations are nucleated in the CoGa during growth. It is clearly shown that the threading dislocations in the CoGa originate at the misfit dislocations at the interface, while the GaAs layer underneath is free of dislocation. [ABSTRACT FROM AUTHOR]

Due to the hazardous implications of releasing CFCs into the environment, studies on their thermal destruction are necessary. The use of incineration to destroy these compounds, while effective, have produced polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDD/PCDF) while releasing large amounts of corrosive HC1 and HF. TheChemChar gasification process was evaluated for its ability to destroy two CFCs, 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and dichlorodifluoromethane (CFC-13). It was found that DRE values of >99.9998% are obtained for the destruction of 1,1,2-trichloro-1,2,2-trifluoroethane while not producing any PCDD/PCDF. Additionally, the chloride(as the potassium salt) and fluoride (as carbon-fluoride) that result from the destruction of both CFCs are retained in the gasification system. This study illustrates that the ChemChar gasification processholds significant promise as an alternative to incineration for the safe and complete destruction of CFCs. [ABSTRACT FROM AUTHOR]