370 research outputs found

    The Myth of Female Underachievement: A Reexamination of Sex Differences in Academic Underachievement

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    14 pagesThis paper examines sex differences in academic underachievement among students who graduated from high school in a western city in 1978. According to data gathered from students' cumulative records for the 7th through 12th grades, males are much more likely than females to have total grade averages and grades in English and mathematics that are lower than would be predicted by their scores on standardized tests of ability. Although the highest achieving females often have lower average ability test scores than the highest achieving males, this results not from the underachievement of the brightest females but from the fact that females with a wide range of ability levels receive good grades and only the very brightest males receive high grades. These sex differences in underachievement appear for middle class and working class students, but often are smaller for the working class and in mathematics grades

    Academic merit, status variables, and students' grades

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    9 pagesStudents' grades are important mechanisms for advancement and success in life. Grades are criteria for college admission and academic awards, and they undoubtedly influence the encouragement and advice students receive regarding their future plans. In using grades in these ways it is assumed that they reflect students' actual achievement. This paper examines this assumption by looking at the extent to which ability, social class, and gender, as well as achievement. influence students' grades in school. Earlier work is extended by including both gender and social class in the analysis and by examining influences on students' grades in each year from the 7th- to the 12th-grade and both the total grade average and marks in the subject areas of mathematics and English. The total grade averages were examined because they have most often been the focus of other studies. English and mathematics grades were examined because of the centrality of these disciplines to the school curriculum and because of the association of achievement in these areas with both gender and social class

    Gender Roles and Behavior in Social Dilemmas: Are there Sex Differences in Cooperation and in its Justification?

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    10 pagesData from two experimental social dilemmas-a set of 66 nine-person dilemmas and a set of 64 seven-person dilemmas-were used to examine sex differences in cooperation. Women were only slightly more likely than men to cooperate with others, and variables related to the experimental setting were much more important influences on behavior than sex. Whether or not the women cooperated, they were more likely than men to justify their behavior as being altruistic and principled, to believe that they were more oriented toward harmonious group relations, and to be less nervous and upset at the end of the experiment. It is suggested that those who speculate on sex differences in cooperation may have overstated these differences and that the relationship between self-schema and behavior may vary depending on the extent to which the attributes studied relate to gender identity

    Impact of facial conformation on canine health: Brachycephalic Obstructive Airway Syndrome

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    The domestic dog may be the most morphologically diverse terrestrial mammalian species known to man; pedigree dogs are artificially selected for extreme aesthetics dictated by formal Breed Standards, and breed-related disorders linked to conformation are ubiquitous and diverse. Brachycephaly–foreshortening of the facial skeleton–is a discrete mutation that has been selected for in many popular dog breeds e.g. the Bulldog, Pug, and French Bulldog. A chronic, debilitating respiratory syndrome, whereby soft tissue blocks the airways, predominantly affects dogs with this conformation, and thus is labelled Brachycephalic Obstructive Airway Syndrome (BOAS). Despite the name of the syndrome, scientific evidence quantitatively linking brachycephaly with BOAS is lacking, but it could aid efforts to select for healthier conformations. Here we show, in (1) an exploratory study of 700 dogs of diverse breeds and conformations, and (2) a confirmatory study of 154 brachycephalic dogs, that BOAS risk increases sharply in a non-linear manner as relative muzzle length shortens. BOAS only occurred in dogs whose muzzles comprised less than half their cranial lengths. Thicker neck girths also increased BOAS risk in both populations: a risk factor for human sleep apnoea and not previously realised in dogs; and obesity was found to further increase BOAS risk. This study provides evidence that breeding for brachycephaly leads to an increased risk of BOAS in dogs, with risk increasing as the morphology becomes more exaggerated. As such, dog breeders and buyers should be aware of this risk when selecting dogs, and breeding organisations should actively discourage exaggeration of this high-risk conformation in breed standards and the show ring

    THE PRESENT STATUS OF THE GERM-CELL PROBLEM IN VERTEBRATES

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    (i) Morphological studies relating to the origin and differentiation of the definitive germ cells in vertebrates have, as indicated, resulted in conflicting views. In many instances two or more competent investigators who have studied the same form have reached different conclusions. (2) Some contend that the germ cells are set aside from the soma during the early stages of embryonic development, and that these alone serve as the progenitors of the functional sex cells. (3) Others recognize an early differentiation of sex cells but hold that these are supplemented by others produced from the somatic epithelium of the gonad in late embryonic or post-embryonic stages. (4) Another group recognizes the early differentiated cells as germ cells but contend that these all degenerate and that the definitive ones are formed from the germinal epithelium. These degenerating germ cells are believed by certain authors to be a phylogenetic recapitulation of the condition in lower forms. (5) Finally, yet another group contends that the so-called primordial germ cells are not germ cells at all but are enlarged cells in some stage of mitosis or in some specific metabolic phase. This group believes that all germ cells are derived from the somatic cells of the germinal epithelium. (6) Experimental work supports the view that the primordial germ cells, which are recognized early, are the progenitors of the definitive sex cells. When these primordial germ cells are prevented from reaching the site of the developing gonad the individual fails to develop sex cells, although a sterile gonad and its associated structures may develop. (7) I suggest that the observed proliferation of germ cells from the germinal epithelium, reported by numerous investigators, can be interpreted in another way by a thorough study of the enlarged germ cells in relation to the epithelium. It seems probable that the cells of the epithelium, which form functional sex elements, are not and never were a part of the mesothelial covering, but are cells which were segregated early, and are merely stored in the epithelium.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74677/1/j.1469-185X.1945.tb00313.x.pd

    Identification of Behaviour in Freely Moving Dogs (Canis familiaris) Using Inertial Sensors

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    Monitoring and describing the physical movements and body postures of animals is one of the most fundamental tasks of ethology. The more precise the observations are the more sophisticated the interpretations can be about the biology of a certain individual or species. Animal-borne data loggers have recently contributed much to the collection of motion-data from individuals, however, the problem of translating these measurements to distinct behavioural categories to create an ethogram is not overcome yet. The objective of the present study was to develop a “behaviour tracker”: a system composed of a multiple sensor data-logger device (with a tri-axial accelerometer and a tri-axial gyroscope) and a supervised learning algorithm as means of automated identification of the behaviour of freely moving dogs. We collected parallel sensor measurements and video recordings of each of our subjects (Belgian Malinois, N=12; Labrador Retrievers, N=12) that were guided through a predetermined series of standard activities. Seven behavioural categories (lay, sit, stand, walk, trot, gallop, canter) were pre-defined and each video recording was tagged accordingly. Evaluation of the measurements was performed by support vector machine (SVM) classification. During the analysis we used different combinations of independent measurements for training and validation (belonging to the same or different individuals or using different training data size) to determine the robustness of the application. We reached an overall accuracy of above 90% perfect identification of all the defined seven categories of behaviour when both training and validation data belonged to the same individual, and over 80% perfect recognition rate using a generalized training data set of multiple subjects. Our results indicate that the present method provides a good model for an easily applicable, fast, automatic behaviour classification system that can be trained with arbitrary motion patterns and potentially be applied to a wide range of species and situations

    Enhanced Auditory Brainstem Response and Parental Bonding Style in Children with Gastrointestinal Symptoms

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    The electrophysiological properties of the brain and influence of parental bonding in childhood irritable bowel syndrome (IBS) are unclear. We hypothesized that children with chronic gastrointestinal (GI) symptoms like IBS may show exaggerated brainstem auditory evoked potential (BAEP) responses and receive more inadequate parental bonding. = 0.024). Multiple regression analysis in females also supported these findings.It is suggested that children with chronic GI symptoms have exaggerated brainstem responses to environmental stimuli and inadequate parental behaviors aggravate these symptoms
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