Signal Characteristics of Civil GPS Jammers

This paper surveys the signal properties of 18 commercially available GPS jammers based on experimental data. The paper is divided into two distinct tests. The first characterizes the jamming signals, and the second test determines the effective range of 4 of the jammers. The first test uses power spectra from discrete Fourier transforms (DFTs) of the time series data to show that all the jammers employ approximately the same jamming method, i.e. linear frequency modulation of a single tone. The spectra also show that there are significant jammer-to-jammer variations, including between jammers of the same model, and that a given jammer’s signal may vary over time. The first test also includes measurements of signal power within frequency bands centered at the L1 and L2 frequencies, along with the sweep periods and the sweep range at both frequencies. The second test presents measurements of the attenuation of the jamming signal necessary to allow a commercially available GPS receiver to acquire and track signals from a GPS simulator. From the attenuation levels and some assumptions about the antennas used, upper limits on the effective jamming ranges are calculated for 4 of the jammers, with a resulting maximum range of 6–9 km.Aerospace Engineering and Engineering Mechanic

Skills and Perceptions of Entry-Level Staff Supervision

The following study consisted of 532 respondents to a survey related to the supervision of entrylevel staff in student affairs. Participants included both supervisors of entry-level staff and entrylevel staff themselves. Individuals shared their thoughts and experiences regarding the supervision of this population. Themes emerged in four areas: Readiness for the supervisory role, challenges related to supervision, supervisor skills, and working through transition. Implications and recommendations for practice and further research are discussed

A Brief Rutgers Alcohol Problem Index with Less Potential for Bias

The Rutgers Alcohol Problem Index (RAPI), a popular measure of alcohol-related problems in adolescents, varies with many theoretically-relevant measures of individual differences, including sex. The sex differences in RAPI scores fit many models of alcohol problems but could also arise from biased items. In addition, a short form could increase the scale’s utility. The current study examined RAPI scores, an additional inventory of problem drinking, and measures of alcohol consumption in over 2,000 college student drinkers. Analyses revealed items that functioned differentially for men and women. Dropping these items created a shorter scale with almost identical psychometric properties but less potential for bias. Correlations with drinking habits and drinking problems were the same as those for the full scale, and the size of the effect for the difference between men and women’s responses remained essentially the same. These results confirm previous work using different analytic approaches, and suggest that a short form of the RAPI could prove helpful in future research. In addition, these data suggest that analyses of differential item functioning in other scales can reveal important information about the measurement of drug problems

Perceived environment and physical activity: a meta-analysis of selected environmental characteristics

BACKGROUND: Several narrative reviews have been conducted on the literature examining environmental correlates of physical activity (PA). To date these reviews have been unable to provide definitive summaries of observed associations. This study utilizes meta-analytical techniques to calculate summaries of associations between selected environmental characteristics and PA. METHODS: Published studies were identified from electronic databases and searches of personal files. Studies were examined to determine the environmental constructs most frequently studied. Included studies (N = 16) examined at least one identified construct and determined associations between perceived environmental constructs and PA using logistic regression. Data were analyzed separately for crude and adjusted ORs using general-variance based fixed effect models. RESULTS: No significant associations emerged between environmental characteristics and PA using crude OR. The perceived presence of PA facilities (OR 1.20, 95% 1.06–1.34), sidewalks (OR 1.23, 95% 1.13–1.32), shops and services (OR 1.30, 95% 1.14–1.46) and perceiving traffic not to be a problem (OR 1.22, 95% 1.08–1.37) were positively associated with activity using adjusted ORs. Variance in PA accounted for by significant associations ranged from 4% (heavy traffic not a problem) to 7% (presence of shops and services). CONCLUSION: Results of the meta-analysis support the relevance of perceived environmental characteristics for understanding population PA. These results should encourage the use of comprehensive ecological models that incorporate variables beyond basic demographic information

Comparing electronic-keypad responses to paper-and-pencil questionnaires in group assessments of alcohol consumption and related attitudes

Electronic versions of questionnaires have the potential to improve research and interventions in the addictions. Administering questionnaires electronically to groups, however, has proven difficult without a multitude of computers, but gathering data electronically from a group could make for easy assessment and quick feedback. Using a sample of 107 college students, we examined the validity of wireless keypad survey responses by comparing them to traditional paper-and-pencil questionnaires. The two formats led to almost identical responses that did not differ significantly from each other (all effect sizes less than g =.15) and high correlations between formats. The wireless, handheld keypad procedure appears to generate data that are as valid as questionnaire responses and permit rapid feedback to groups, as well as easy, human error-free data entry for analysis

New hurdles for translational research

New guidelines for the collection and use of human tissues for research will impose new requirements on researchers to seek ethical approval and patient consent. This extends to the use of surplus tissue, such as breast cancer excision biopsies, which, until recently, have been regarded as having been 'abandoned' by the patient. This article argues that some of these new constraints provide hurdles to translational research that are unnecessary for patient protection. This is particularly significant when emerging technologies are expected to elicit major advances in clinical cancer research

Reducing heavy drinking in college males with the decisional balance: Analyzing an element of Motivational Interviewing

The decisional balance, a brief detailing of the advantages and disadvantages of behavior change, serves as a key component to interventions in Motivational Interviewing. The impact of this component alone is not well understood. Forty-seven men completed a Timeline Followback interview assessing alcohol consumption and unsafe sexual practices. They then completed a decisional balance, listing the Pros and Cons of decreasing their drinking, but not one for safer sex. One-month follow-up data showed that they had statistically significant and clinically meaningful increases in their motivation to alter drinking and decreases in the number of drinks that they intended to drink, the actual drinks consumed per month, the days per month that they drank, their maximum number of drinks consumed on one occasion, and their average number of drinks per occasion. They did not alter their sexual behavior or their motivation to increase safe sex behavior. These results suggest that the decisional balance plays an important role in Motivational Interviewing and could serve as a quick and efficient intervention by itself

A Brief Decisional Balance Intervention Increases Motivation and Behavior Regarding Condom Use in High-risk Heterosexual College Men

Male college students constitute one of a number of at-risk populations susceptible to receiving and transferring sexually transmitted infections. Interventions designed to increase condom use have produced mixed results, but increasing motivation to use condoms may decrease risky sexual behavior. The current study examined the decisional balance, a component of Motivational Interviewing (MI), as an intervention to promote condom use. A total of 41 college men at-risk for negative outcomes from both unsafe sex and drinking participated. They reported both infrequent condom use and heavy drinking. Immediately following a decisional balance on condom use, three separate measures of motivation to change condom use increased. Further, participants reported increases in actual condom use at a 30-day follow-up. Participants did not alter their drinking behavior or their motivation to decrease problematic alcohol use. The findings provide preliminary support for the efficacy of a brief decisional balance intervention to increase safer-sex motivation and behaviors, but similar designs with true control groups receiving assessment only and larger numbers of participants are required before they can be generalized to the greater population of college students. College health professionals might adopt similar brief motivational enhancement interventions with the decisional balance to promote safer sex among at-risk college students

Manipulation of the Spatial Grazing Behaviour of Livestock in Extensive Grassland Systems

Spatial behaviour of livestock is a critical factor in grassland management. Recent and ongoing research suggests that new approaches can be used to manipulate where cattle graze. The combination of strategic supplement placement and low-stress herding can be used to target cattle grazing and potentially may be useful for managing fine fuels. A phenotype to genotype association study of cattle spatial behavior suggests that use of rugged terrain and areas far from water is inherited. Although more research is needed, selection for animals specifically adapted for mountainous terrain or extensive paddocks may be an alternative for managing grasslands in the near future

Cardiomyopathy Secondary to Thyroid and Parathyroid Dysfunction: Case Report and Literature Review

Heart failure due to metabolic derangements is not common in clinical practice. However, outcome is usually positive given that the precipitating factor is recognized and treatment is initiated in a timely fashion. We report an unusual case of reduced left ventricular systolic function as a result of hypocalcemia and long standing untreated primary hypothyroidism in a patient without structural heart disease. Delay in seeking appropriate medical attention for both disorders has culminated in cardiac dysfunction that was favorably altered with correction of underlying etiologies. Therefore, early recognition and expedient management of hypocalcemia and hypothyroidism can result in an imminent improvement of cardiac function