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121.
We examine the announcements of high tech mergers using a relatively new proxy for growth options we call “growth to book.” We find this adds significantly to help explain the premiums paid and announcement period abnormal returns when acquiring tech targets. Higher synergies are expected by managers and investors when targets have low growth options and acquirers have high growth options, resulting in higher premiums paid and either less negative or more positive abnormal returns. However, we find significant variation in the results by the relative size of the target and when low growth to book (GTB) firms acquire. While high GTB acquirers tend to pay more in premiums, low GTB acquirers can pay higher premiums and receive some of the most negative returns at announcement. We find evidence some acquisitions are motivated by desperation as these acquirers have the lowest GTB and do a disproportionate number of the relatively largest deals, receiving the worst abnormal returns at announcement. 相似文献
122.
123.
Scott C. Wearing I. S. Davis T. Brauner S. L. Hooper T. Horstmann 《Journal of sports sciences》2013,31(23):2735-2743
ABSTRACTThe capacity of foot-strike running patterns to influence the functional properties of the Achilles tendon is controversial. This study used transmission-mode ultrasound to investigate the influence of habitual running foot-strike pattern on Achilles tendon properties during barefoot walking and running. Fifteen runners with rearfoot (RFS) and 10 with a forefoot (FFS) foot-strike running pattern had ultrasound transmission velocity measured in the right Achilles tendon during barefoot walking (≈1.1 ms?1) and running (≈2.0 ms?1). Temporospatial gait parameters, ankle kinematics and vertical ground reaction force were simultaneously recorded. Statistical comparisons between foot-strike patterns were made using repeated measure ANOVAs. FFS was characterised by a significantly shorter stance duration (?4%), greater ankle dorsiflexion (+2°), and higher peak vertical ground reaction force (+20% bodyweight) than RFS running (P < .05). Both groups adopted a RFS pattern during walking, with only the relative timing of peak dorsiflexion (3%), ground reaction force (1–2%) and peak vertical force loading rates (22–23%) differing between groups (P < .05). Peak ultrasound transmission velocity in the Achilles tendon was significantly higher in FFS during walking (≈100 ms?1) and running (≈130 ms?1) than RFS (P < .05). Functional Achilles tendon properties differ with habitual footfall patterns in recreational runners. 相似文献
124.
Morgan E. Chaffin Kris E. Berg Jessica R. Meendering Tamra L. Llewellyn Jeffrey A. French Jeremy E. Davis 《Research quarterly for exercise and sport》2013,84(4):693-701
The purpose of this study was to determine if a difference in interleukin-6 (IL-6) and delayed onset muscles soreness (DOMS) exists in two different phases of the menstrual cycle. Nine runners performed one 75-min high-intensity interval running session during the early follicular (EF) phase and once during the midluteal (ML) phase of the menstrual cycle. Estrogen and progesterone levels were significantly reduced in the EF phase when compared to the ML phase. IL-6 levels increased from pre- to postexercise in the EF and ML phases (p < .001). There was no relationship between the IL-6 level and DOMS. The results suggest that menstruating female runners need not vary training throughout the month to reduce DOMS. 相似文献
125.
Abstract This paper reports a simple experiment which explores young children's written representation of number. Previous research (e.g. Hughes, 1983; Sinclair, Siegrist & Sinclair, 1982) has shown that several factors may influence the extent to which children will spontaneously deploy their knowledge of numerals to represent numerosity, but the available evidence is insufficient to provide a clear account of the relative weight of these factors. The present experiment involved presenting five to six year‐old children with arrays of simple objects and manipulating the wording of the instructions. The results showed that the use of the term ‘how many’ led the vast majority of the children to show numerosity by using materials. In contrast, when asked to represent ‘what’ they could see, most children concerned themselves with depicting the nature of the objects in the array by drawing or writing. These findings suggest that the linguistic context of the task is important in determining the children's representational strategies. Furthermore, it is argued that children's understanding of number and their ability to use numerals is quite separable from their knowledge of when it is appropriate to deploy these skills. 相似文献
126.
Two studies were conducted to assess the effects of rapid eye movement (REM) sleep deprivation on shock-elicited aggression. REM deprivation periods of 0, 24, 48, and 72 h were used in the first study, while 48-, 72-, 96-, and 120-h periods were used in the second study. Both studies indicated that increases in REM deprivation (up to 96 h) resulted in increases in the number of aggressive responses. A decrease was shown by the 120-h group. A drive-energization or motivational-effects model is suggested. 相似文献
127.
Rats were trained to leave an array of food after they had consumed a fixed number (three, four, or five) of food items. This discrimination remained in effect despite a shift from 45-mg Noyes pellets to larger and irregularly sized sunflower seeds. The present demonstration replicates work first reported 50 years ago by Otto Koehler and his associates (e.g., Marold, 1939; see also Koehler, 1950), who used avian subjects, and, like those studies, it involved both positive and negative social reinforcement. The present procedure provided a rare instance in which numerical control was exerted over behavior that was primarily consummatory in nature. The results are viewed in terms of the wider literature of numerical competence in animals and are discussed in terms of a numerical process known asprotocounting (Davis & P’erusse, 1988b). 相似文献
128.
Andrew S. Davis 《Psychology in the schools》2006,43(4):503-512
A clear link exists between neurological dysfunction and psychopathology in children, as evidenced by research on the sequelae of developmental childhood brain impairment, the neuropsychological investigation of children with psychiatric disorders, and neuroimaging research. Understanding the neuropsychological basis of a disorder helps teachers, parents, and children better understand the etiology of the disorder and guide classroom interventions. Additionally, identifying morphological markers of childhood mental disorders may lead to earlier and more successful interventions. This article reviews the neuropsychological relationships between brain impairment and childhood mental disorders as well as investigates the biological basis for some common childhood disorders seen in the schools. Emphasis is placed upon the underlying neurological and neuropsychological deficits that constitute disorders, and implications for practitioners are discussed. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 503–512, 2006. 相似文献
129.
High infant mortality rates among American Indians are disproportionate to state statistics for other races and higher than the national average. These findings prompted a community health center in a large Midwestern city to create and provide an American Indian infant mortality reduction project in the early 1990s. Strategies for program implementation included networking with local organizations, communicating with reservation health clinics throughout the state, educating American Indian mothers and their community about factors contributing to American Indian infant mortality, and providing individual case management to American Indian women and infants. We offer this article for three reasons: This grant project was successful, disparity in rates of infant mortality among peoples of color continues, and a paucity of information exists about the health behaviors of American Indian women. 相似文献
130.
High turnover and short tenures are the norm for state university presidents in the last part of the twentieth century. Depending on the type of institution, the average state university president stays in office about four years, some three years shorter than the national average of seven years for all higher education institutions. The article discusses this trend and relates length of tenure to the formal and informal evaluations of presidents. Beginning with a presentation of presidential tenure (time in office) data and a discussion of the benefits of longer terms, the article continues with a dialogue on the role of the president in state institutions of higher education. It is argued that the position of president necessitates constituent leadership with presidents often expected to please all constituencies. Included in this discussion are the nature, role, and effectiveness of evaluations of university presidents. The authors conclude that evaluations of presidents make little difference in decisions to retain or remove presidents. Even a good or great evaluation does not offset the impact of the unforseen event or changes in political leadership within a state or on a board. The authors agree that annual reviews or reports are valuable in improving a presidents performance and leadership. Evaluations make a difference when they are supervised by individuals with direct knowledge of the job, are fair in terms of expectations from often divergent constituent groups, and focus on maximizing the ability of the president to improve the institution. 相似文献