262 research outputs found
High rate locally-correctable and locally-testable codes with sub-polynomial query complexity
In this work, we construct the first locally-correctable codes (LCCs), and
locally-testable codes (LTCs) with constant rate, constant relative distance,
and sub-polynomial query complexity. Specifically, we show that there exist
binary LCCs and LTCs with block length , constant rate (which can even be
taken arbitrarily close to 1), constant relative distance, and query complexity
. Previously such codes were known to exist
only with query complexity (for constant ), and
there were several, quite different, constructions known.
Our codes are based on a general distance-amplification method of Alon and
Luby~\cite{AL96_codes}. We show that this method interacts well with local
correctors and testers, and obtain our main results by applying it to suitably
constructed LCCs and LTCs in the non-standard regime of \emph{sub-constant
relative distance}.
Along the way, we also construct LCCs and LTCs over large alphabets, with the
same query complexity , which additionally have
the property of approaching the Singleton bound: they have almost the
best-possible relationship between their rate and distance. This has the
surprising consequence that asking for a large alphabet error-correcting code
to further be an LCC or LTC with query
complexity does not require any sacrifice in terms of rate and distance! Such a
result was previously not known for any query complexity.
Our results on LCCs also immediately give locally-decodable codes (LDCs) with
the same parameters
Multiple Mediations in Zora Neale Hurston's Mules and Men
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67224/2/10.1177_0308275X9301300404.pd
Cardiovascular Disease Risk Factors and Physical Fitness in Volunteer Firefighters
International Journal of Exercise Science 12(2): 764-776, 2019. Forty-seven percent of volunteer firefighter line of duty deaths are caused by cardiovascular events. Aggressive cardiovascular disease (CVD) risk factor reduction and improved physical fitness could reduce CVD mortality within this population. We assessed CVD risk factors and physical fitness in a large cohort of volunteer firefighters to help establish a health and fitness profile of this population, which may serve as evidence for the need to initiate programs aimed at reducing morbidity and mortality caused by CVD in the volunteer fire service. Seventy-four male volunteer firefighters were assessed for eight CVD risk factors and anthropometric characteristics. Physical fitness was assessed via push-ups, sit-ups, and the YMCA step test. Sixty-eight percent of the firefighters had two or more CVD risk factors. The sample was considered obese via body fat percentage (25.3 ± 5.7%), 27% were hypertensive, 30% had hypercholesterolemia, and 46% were sedentary. The average number of sit-ups performed was 27.3 ± 10.5, which was ranked in the 25thpercentile. The average heart rate after the YMCA step test was 160.2 ± 14.6 bpm, which was ranked very poor. The number of CVD risk factors and poor physical fitness in this cohort of volunteer firefighters was noteworthy. Most volunteer firefighters in our sample were at elevated risk for CVD and had inadequate physical fitness. This evidence conveys the need to initiate physical activity and nutrition outreach programs, led by health and fitness professionals, aimed at reducing firefighter morbidity and mortality within the volunteer fire service
Masculinity, Injury and Death – Exploring Anti-Knife-carrying Messages
Although knives are the most common homicide instrument in Britain, factors that influence knife-carrying tolerance (i.e., the extent to which it is seen as acceptable and justified) and perceptions of anti-knife messages (i.e., slogans and posters aimed at reducing knife crime) have not been examined, which the current paper will cover by featuring progressively related studies. In Study 1, 227 men took part in a study on factors associated with knife-carrying. In Study 2, 200 participants took part in an experimental study on anti-knife slogans. In Study 3, 169 men took part in a study on existing anti-knife injury posters. In Study 4, 151 men took part in a study on anti-knife CGI posters. Study 1 proposes a structural equation model that shows the inter-correlations between physical defence ability, limited trust in authority, limited control over one’s status and the need for respect, and how they predict aggressive masculinity (i.e. macho culture), which, in turn, predicts knife-carrying tolerance. The model also reveals two significant latent factors: saving face inter-male competition (i.e., honor) and perceived social ecological constraints (i.e., socio-economic limitations). Study 2 shows that the injury slogan was rated as most persuasive. Study 3 shows that the fresh injury poster was rated as most persuasive, emotional and believable. Study 4 shows that it was the eye injury that was rated as most persuasive, emotional and believable. The paper supports protection motivation theory and offers practical insights into tackling knife crime
Astrometry with Hubble Space Telescope: A Parallax of the Fundamental Distance Calibrator RR Lyrae
We present an absolute parallax and relative proper motion for the
fundamental distance scale calibrator, RR Lyr. We obtain these with astrometric
data from FGS 3, a white-light interferometer on HST. We find mas. Spectral classifications and VRIJHKTM and DDO51 photometry of
the astrometric reference frame surrounding RR Lyr indicate that field
extinction is low along this line of sight. We estimate =0.07\pm0.03 for
these reference stars. The extinction suffered by RR Lyr becomes one of the
dominant contributors to the uncertainty in its absolute magnitude. Adopting
the average field absorption, =0.07 \pm 0.03, we obtain M_V^{RR} = 0.61
^{-0.11}_{+0.10}. This provides a distance modulus for the LMC, m-M = 18.38 -
18.53^{-0.11}_{+0.10} with the average extinction-corrected magnitude of RR Lyr
variables in the LMC, , remaining a significant uncertainty. We compare
this result to more than 80 other determinations of the distance modulus of the
LMC.Comment: Several typos corrected. To appear in The Astronomical Journal,
January 200
Cost-consciousness among Swiss doctors: a cross-sectional survey
BACKGROUND: Knowing what influences physicians attitudes toward health care costs is an important matter, because most health care expenditures are the results of doctors' decisions. Many decisions regarding medical tests and treatments are influenced by factors other than the expected benefit to the patient, including the doctor's demographic characteristics and concerns about cost and income. METHODS: Doctors (n = 1184) in Geneva, Switzerland, answered questions about their cost-consciousness, practice patterns (medical specialty, public.vs. private sector, number of patients per week, time spent with a new patient), work satisfaction, and stress from uncertainty. General linear models were used to identify independent risk factors of higher cost-consciousness. RESULTS: Most doctors agreed that trying to contain costs was their responsibility ("agree" or "totally agree": 90%) and that they should take a more prominent role in limiting the use of unnecessary tests (92%); most disagreed that doctors are too busy to worry about costs (69%) and that the cost of health care is only important if the patient has to pay for it out-of-pocket (88%). In multivariate analyses, cost-consciousness was higher among doctors in the public sector, those who saw fewer patients per week, who were most tolerant of uncertainty, and who were most satisfied with their work. CONCLUSION: Thus even in a setting with very high health care expenditures, doctors' stated cost-consciousness appeared to be generally high, even though it was not uniformly distributed among them
Clinical Psychologists’ Firearm Risk Management Perceptions and Practices
The purpose of this study was to investigate the current perceptions and practices of discussing firearm risk management with patients diagnosed with selected mental health problems. A three-wave survey was mailed to a national random sample of clinical psychologists and 339 responded (62%). The majority (78.5%) believed firearm safety issues were greater among those with mental health problems. However, the majority of clinical psychologists did not have a routine system for identifying patients with access to firearms (78.2%). Additionally, the majority (78.8%) reported they did not routinely chart or keep a record of whether patients owned or had access to firearms. About one-half (51.6%) of the clinical psychologists reported they would initiate firearm safety counseling if the patients were assessed as at risk for self-harm or harm to others. Almost half (46%) of clinical psychologists reported not receiving any information on firearm safety issues. Thus, the findings of this study suggest that a more formal role regarding anticipatory guidance on firearms is needed in the professional training of clinical psychologists
Who uses firearms as a means of suicide? A population study exploring firearm accessibility and method choice
<p>Abstract</p> <p>Background</p> <p>The 1996 Australian National Firearms Agreement introduced strict access limitations. However, reports on the effectiveness of the new legislation are conflicting. This study, accessing all cases of suicide 1997-2004, explores factors which may impact on the choice of firearms as a suicide method, including current licence possession and previous history of legal access.</p> <p>Methods</p> <p>Detailed information on all Queensland suicides (1997-2004) was obtained from the Queensland Suicide Register, with additional details of firearm licence history accessed from the Firearm Registry (Queensland Police Service). Cases were compared against licence history and method choice (firearms or other method). Odds ratios (OR) assessed the risk of firearms suicide and suicide by any method against licence history. A logistic regression was undertaken identifying factors significant in those most likely to use firearms in suicide.</p> <p>Results</p> <p>The rate of suicide using firearms in those with a current license (10.92 per 100,000) far exceeded the rate in those with no license history (1.03 per 100,000). Those with a license history had a far higher rate of suicide (30.41 per 100,000) compared to that of all suicides (15.39 per 100,000). Additionally, a history of firearms licence (current or present) was found to more than double the risk of suicide by any means (OR = 2.09, <it>P </it>< 0.001). The group with the highest risk of selecting firearms to suicide were older males from rural locations.</p> <p>Conclusion</p> <p>Accessibility and familiarity with firearms represent critical elements in determining the choice of method. Further licensing restrictions and the implementation of more stringent secure storage requirements are likely to reduce the overall familiarity with firearms in the community and contribute to reductions in rates of suicide.</p
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