Muscle Strength Training Alters Muscle Activation of the Lower Extremity during Side-Step Cutting in Females

Abstract

The objective of this study was to examine the effects of muscle strength training on knee kinematics/kinetics and muscle activation patterns during anticipated side-step cutting. Three-dimensional knee kinematics/kinetics data and muscle activation of selected lower extremity muscles were measured while performing cutting before and after completing 10-week circuit strength training mixed typical resistance training and power training (intervention) or no training (control) from 25 female subjects. The muscle strength of quadriceps and hamstrings were measured before and after training using isokinetic dynamometer. No statistically significant differences were observed in quadriceps and hamstrings muscle strength, all kinematic/kinetic variables, and muscle activation for the control group. Both quadriceps (p?=?0.005) and hamstrings (p?=?0.030) muscle strength were increased after training. An increased biceps femoris (p?=?0.003) and H:Q ratio of activation (p?=?0.016), as well as decreased gastrocnemius muscle activation (p?=?0.012) during pre-activation phase in intervention group were found. No significant differences were found in knee kinematics and kinetics both at the time frame of the initial contact and the peak tibial anterior shear force after training. In conclusion, muscle strength training altered some muscle activations of lower extremity muscles, which might affect the risk of ACL injury, but it did not change the kinematic/kinetic parameters.     

Expertise in Deception Detection Involves Actively Prompting Diagnostic Information Rather Than Passive Behavioral Observation

In a proof‐of‐concept study, an expert obtained 100% deception‐detection accuracy over 33 interviews. Tapes of the interactions were shown to N = 136 students who obtained 79.1% accuracy (Mdn = 83.3%, mode = 100%). The findings were replicated in a second experiment with 5 different experts who collectively conducted 89 interviews. The new experts were 97.8% accurate in cheating detection and 95.5% accurate at detecting who cheated. A sample of N = 34 students watched a random sample of 36 expert interviews and obtained 93.6% accuracy. The data suggest that experts can accurately distinguish truths from lies when they are allowed to actively question a potential liar, and nonexperts can obtain high accuracy when viewing expertly questioned senders.     

The Use of Exploratory Factor Analysis and Principal Components Analysis in Communication Research

Exploratory factor analysis is a popular statistical technique used in communication research. Although exploratory factor analysis (EFA) and principal components analysis (PCA) are different techniques, PCA is often employed incorrectly to reveal latent constructs (i.e., factors) of observed variables, which is the purpose of EFA. PCA is more appropriate for reducing measured variables into a smaller set of variables (i.e., components) by keeping as much variance as possible out of the total variance in the measured variables. Furthermore, the popular use of varimax rotation raises some concerns about the relationships among the factors that researchers claim to discover. This paper discusses the distinct purposes of PCA and EFA, using two data sets as examples to highlight the differences in results between these procedures, and also reviews the use of each technique in three major communication journals: Communication Monographs, Human Communication Research, and Communication Research.     

Assessing Item Fit for Unidimensional Item Response Theory Models Using Residuals from Estimated Item Response Functions

Residual analysis (e.g. Hambleton & Swaminathan, Item response theory: principles and applications, Kluwer Academic, Boston, 1985; Hambleton, Swaminathan, & Rogers, Fundamentals of item response theory, Sage, Newbury Park, 1991) is a popular method to assess fit of item response theory (IRT) models. We suggest a form of residual analysis that may be applied to assess item fit for unidimensional IRT models. The residual analysis consists of a comparison of the maximum-likelihood estimate of the item characteristic curve with an alternative ratio estimate of the item characteristic curve. The large sample distribution of the residual is proved to be standardized normal when the IRT model fits the data. We compare the performance of our suggested residual to the standardized residual of Hambleton et al. (Fundamentals of item response theory, Sage, Newbury Park, 1991) in a detailed simulation study. We then calculate our suggested residuals using data from an operational test. The residuals appear to be useful in assessing the item fit for unidimensional IRT models.     

Using online social media,Facebook, in screening for major depressive disorder among college students

This study explored the feasibility of using Internet social networking media in an online program for Major Depressive Disorder (MDD) screening and psychoeducation targeting college students. A Facebook advertisement targeted students at five colleges in the United States to complete a mental health research survey that screened for MDD using the Patient Health Questionnaire-9 (PHQ-9). Students who screened positive for MDD were offered an eightweek follow-up survey. Of the 259 students who consented to participate in the study, 26.7% screened positive for MDD, while only 14.2% were receiving treatment. The use of Facebook to advertise for online screening for MDD required very little start-up time, and the average cost was $11.45 per subject recruited. It is feasible to use online, commercially available social networking media such as Facebook for online screening for MDD among college students. However, conducting online screening and offering treatment resources alone did not increase treatment rate in this population.     

Social identity,attribution, and emotion: Comparisons of Americans,Korean Americans,and Koreans

The social identity of another person, in addition to the social identity of self, can be an important factor affecting the types of attribution judgments and emotions that individuals indicate for the other person. In April 2007, the perpetrator of the shooting incident on the Virginia Tech University campus was identified as a person who emigrated to the USA from Korea at a young age. The current study compared non‐Korean Americans, Korean Americans, Koreans in the USA, and Koreans in Korea in terms of their attributions and emotions concerning the perpetrator and the shooting incident. Participants were asked to indicate (1) the extent to which they attributed the cause of the incident to either American society or the perpetrator, (2) their emotions (e.g., upset), and (3) the extent to which they categorized the perpetrator as an American, a Korean American, or a Korean. The results indicated that non‐Korean Americans were most likely to attribute the cause of the incident to the perpetrator as opposed to American society. Non‐Korean Americans, Korean Americans, and Koreans in the United States had more negative emotions (e.g., unhappy, sad, and upset) about the incident than Koreans in Korea did. The results also indicated that individuals differed in their attributions and emotions depending on how they categorized the perpetrator. For example, categorizing the perpetrator as being a Korean was positively related to Americans’ tendency to hold the perpetrator responsible, while categorizing the perpetrator as being an American was negatively related to the tendency to hold the perpetrator responsible among Koreans in Korea. The findings may imply that social identity theory, intergroup emotion theory, and cultural orientations (e.g., individualism and collectivism) can provide insights into people's reactions to a tragic incident.     

Use of the Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood: Revised Edition (DC:0–3R) with Canadian Infants and Young Children Prenatally Exposed to Substances

The current study examined the mental health diagnostic profiles of infants and young children prenatally exposed to substances using the Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood, Revised (DC:0–3R) diagnostic system. Participants were 46 biological mother–infant dyads who were engaged in a clinical program for mothers with substance‐use problems and their young children (aged 10–41 months). Diagnostic information was reported for each of the five axes listed in the DC:0–3R diagnostic system based on file reviews. In addition, the children's socioemotional and adaptive behaviors were assessed using the Child Behavior Checklist, Infant–Toddler Social Emotional Assessment, the Social‐Emotional Scale, and the Adaptive Behavior Assessment System (2nd ed.). In this sample of young children with prenatal substance exposure, a broad range of socioemotional symptoms were evident, with almost one third of the children meeting criteria for at least one Axis I mental health diagnosis. In addition, the majority of dyads demonstrated features of a disordered relationship. Children in more problematic relationships demonstrated higher levels of socioemotional and adaptive functioning difficulties and were more likely to have an Axis I diagnosis than were children in adapted relationships. The importance of early intervention efforts aimed at infants with prenatal substance exposure and their biological mothers is highlighted, with a particular focus on enhancing the quality of the mother–child relationship.     

The Creativity Crisis: The Decrease in Creative Thinking Scores on the Torrance Tests of Creative Thinking

The Torrance Tests of Creative Thinking (TTCT) was developed in 1966 and renormed five times: in 1974, 1984, 1990, 1998, and 2008. The total sample for all six normative samples included 272,599 kindergarten through 12th grade students and adults. Analysis of the normative data showed that creative thinking scores remained static or decreased, starting at sixth grade. Results also indicated that since 1990, even as IQ scores have risen, creative thinking scores have significantly decreased. The decrease for kindergartners through third graders was the most significant.