686 research outputs found
Law, Liberty and the Rule of Law (in a Constitutional Democracy)
In the hunt for a better--and more substantial--awareness of the âlaw,â The author intends to analyze the different notions related to the ârule of lawâ and to criticize the conceptions that equate it either to the sum of âlawâ and âruleâ or to the formal assertion that âlaw rules,â regardless of its relationship to certain principles, including both ânegativeâ and âpositiveâ liberties. Instead, he pretends to scrutinize the principles of the ârule of law,â in general, and in a âconstitutional democracy,â in particular, to conclude that the tendency to reduce the âdemocratic principleâ to the âmajority ruleâ (or âmajority principleâ), i.e. to whatever pleases the majority, as part of the âpositive liberty,â is contrary both to the ânegative libertyâ and to the ârule of lawâ itself
Entrepreneursâ age, institutions, and social value creation goals: a multi-country study
This study explores the relationship between an entrepreneur's age and his/her social value creation goals. Building on the lifespan developmental psychology literature and institutional theory, we hypothesize a U-shaped relationship between entrepreneursâ age and their choice to create social value through their ventures, such that younger and older entrepreneurs create more social value with their businesses while middle age entrepreneurs are relatively more economically and less socially oriented with their ventures. We further hypothesize that the quality of a countryâs formal institutions in terms of economic, social, and political freedom steepen the U-shaped relationship between entrepreneursâ age and their choice to pursue social value creation as supportive institutional environments allow entrepreneurs to follow their age-based preferences. We confirm our predictions using multilevel mixed-effects linear regressions on a sample of over 15,000 entrepreneurs (aged between 18 and 64 years) in 45 countries from Global Entrepreneurship Monitor data. The findings are robust to several alternative specifications. Based on our findings, we discuss implications for theory and practice, and we propose future research directions
Wilson Lines and a Canonical Basis of SU(4) Heterotic Standard Models
The spontaneous breaking of SU(4) heterotic standard models by Z_3 x Z_3
Wilson lines to the MSSM with three right-handed neutrino supermultiplets and
gauge group SU(3)_C x SU(2)_L x U(1) x U(1) is explored. The two-dimensional
subspace of the Spin(10) Lie algebra that commutes with su(3)_C + su(2)_L is
analyzed. It is shown that there is a unique basis for which the initial soft
supersymmetry breaking parameters are uncorrelated and for which the U(1) x
U(1) field strengths have no kinetic mixing at any scale. If the Wilson lines
"turn on" at different scales, there is an intermediate regime with either a
left-right or a Pati-Salam type model. We compute their spectra directly from
string theory, and adjust the associated mass parameter so that all gauge
parameters exactly unify. A detailed analysis of the running gauge couplings
and soft gaugino masses is presented.Comment: 59 pages, 9 figure
Foliar ÎŽ15N values characterize soil N cycling and reflect nitrate or ammonium preference of plants along a temperate grassland gradient
The natural abundance of stable 15N isotopes in soils and plants is potentially a simple tool to assess ecosystem N dynamics. Several open questions remain, however, in particular regarding the mechanisms driving the variability of foliar ÎŽ15N values of non-N2 fixing plants within and across ecosystems. The goal of the work presented here was therefore to: (1) characterize the relationship between soil net mineralization and variability of foliar ÎÎŽ15N (ÎŽ15Nleaf â Ύ15Nsoil) values from 20 different plant species within and across 18 grassland sites; (2) to determine in situ if a plantâs preference for NO3â or NH4+ uptake explains variability in foliar ÎÎŽ15N among different plant species within an ecosystem; and (3) test if variability in foliar ÎÎŽ15N among species or functional group is consistent across 18 grassland sites. ÎÎŽ15N values of the 20 different plant species were positively related to soil net mineralization rates across the 18 sites. We found that within a site, foliar ÎÎŽ15N values increased with the speciesâ NO3â to NH4+ uptake ratios. Interestingly, the slope of this relationship differed in direction from previously published studies. Finally, the variability in foliar ÎÎŽ15N values among species was not consistent across 18 grassland sites but was significantly influenced by N mineralization rates and the abundance of a particular species in a site. Our findings improve the mechanistic understanding of the commonly observed variability in foliar ÎÎŽ15N among different plant species. In particular we were able to show that within a site, foliar ÎŽ15N values nicely reflect a plantâs N source but that the direction of the relationship between NO3â to NH4+ uptake and foliar ÎÎŽ15N values is not universal. Using a large set of data, our study highlights that foliar ÎÎŽ15N values are valuable tools to assess plant N uptake patterns and to characterize the soil N cycle across different ecosystems
Higher occurrence of nausea and vomiting after total hip arthroplasty using general versus spinal anesthesia: an observational study.
BACKGROUND: Under the assumption that postoperative nausea and vomiting (PONV) may occur after total hip arthroplasty (THA) regardless of the anesthetic technique used, it is not clear whether general (GA) or spinal (SA) anesthesia has higher causal effect on this occurrence. Conflicting results have been reported.
METHODS: In this observational study, we selected all elective THA interventions performed in adults between 1999 and 2008 in a Swiss orthopedic clinic under general or spinal anesthesia. To assess the effect of anesthesia type on the occurrence of PONV, we used the propensity score and matching methods, which allowed us to emulate the design and results of an RCT.
RESULTS: Among 3922 procedures, 1984 (51Â %) patients underwent GA, of which 4.1Â % experienced PONV, and 1938 underwent SA, of which 3.5Â % experienced PONV. We found that the average treatment effect on the treated, i.e. the effect of anesthesia type for a sample of individuals that actually received spinal anesthesia compared to individuals who received GA, was ATETâ=â2.00Â % [95Â % CI, 0.78-3.19Â %], which translated into an ORâ=â1.97 [95Â % CI 1.35; 2.87].
CONCLUSION: This suggests that the type of anesthesia is not neutral regarding PONV, general anesthesia being more strongly associated with PONV than spinal anesthesia in orthopedic surgery
Income in Adult Survivors of Childhood Cancer.
INTRODUCTION: Little is known about the impact of childhood cancer on the personal income of survivors. We compared income between survivors and siblings, and determined factors associated with income. METHODS: As part of the Swiss Childhood Cancer Survivor Study (SCCSS), a questionnaire was sent to survivors, aged â„18 years, registered in the Swiss Childhood Cancer Registry (SCCR), diagnosed at age 4'500 CHF), even after we adjusted for socio-demographic and educational factors (OR = 0.46, p<0.001). Older age, male sex, personal and parental education, and number of working hours were associated with high income. Survivors of leukemia (OR = 0.40, p<0.001), lymphoma (OR = 0.63, p = 0.040), CNS tumors (OR = 0.22, p<0.001), bone tumors (OR = 0.24, p = 0.003) had a lower income than siblings. Survivors who had cranial irradiation, had a lower income than survivors who had no cranial irradiation (OR = 0.48, p = 0.006). DISCUSSION: Even after adjusting for socio-demographic characteristics, education and working hours, survivors of various diagnostic groups have lower incomes than siblings. Further research needs to identify the underlying causes
Tunable Frohlich Polarons in Organic Single-Crystal Transistors
In organic field effect transistors (FETs), charges move near the surface of
an organic semiconductor, at the interface with a dielectric. In the past, the
nature of the microscopic motion of charge carriers -that determines the device
performance- has been related to the quality of the organic semiconductor.
Recently, it has been appreciated that also the nearby dielectric has an
unexpectedly strong influence. The mechanisms responsible for this influence
are not understood. To investigate these mechanisms we have studied transport
through organic single crystal FETs with different gate insulators. We find
that the temperature dependence of the mobility evolves from metallic-like to
insulating-like with increasing the dielectric constant of the insulator. The
phenomenon is accounted for by a two-dimensional Frohlich polaron model that
quantitatively describes our observations and shows that increasing the
dielectric polarizability results in a crossover from the weak to the strong
polaronic coupling regime
Validation of a susceptibility, benefits, and barrier scale for mammography screening among Peruvian women: a cross-sectional study
<p>Abstract</p> <p>Background</p> <p>Perceived beliefs about breast cancer and breast cancer screening are important predictors for mammography utilization. This study adapted and validated the Champion's scale in Peru. This scale measures perceived susceptibility for breast cancer and perceived benefits and barriers for mammography.</p> <p>Methods</p> <p>A cross-sectional study was conducted among women ages 40 to 65 attending outpatient gynecology services in a public hospital in Peru. A group of experts developed and pre-tested a Spanish version of the Champion's scale to assess its comprehensibility (N = 20). Factor analysis, internal consistency, and test-retest reliability analyses were performed (N = 285). Concurrent validity compared scores from participants who had a mammogram and those who did not have it in the previous 15 months. T-test and multiple regression analysis adjusting for socio-demographic factors, mammography knowledge and other preventive behaviors were performed.</p> <p>Results</p> <p>The construct validity and reliability were optimal. Cronbach-Alpha coefficients were 0.75 (susceptibility), 0.72 (benefits) and 0.86 (barriers). Concurrent validity analysis showed an association between barriers and mammography screening use in bivariate (22.3 ± 6.7 vs. 30.2 ± 7.6; p < 0.001) and multiple regression analysis (OR = 0.28, 95% CI = 0.18-0.43). Ages 50-60 years (OR = 2.35, 95% CI = 1.19-4.65), history of prior Papanicolaou test (OR = 3.69, 95% CI = 1.84-7.40), and knowledge about breast cancer and mammography (OR = 3.69, 95% CI = 1.84-7.40) were also independently associated with mammography screening use.</p> <p>Conclusion</p> <p>Concurrent validity analysis showed that the Champion's scale has important limitations for assessing perceived susceptibility for breast cancer and perceived benefits for mammography among Peruvian women. There is still a need for developing valid and reliable instruments for measuring perceived beliefs about breast cancer and mammography screening among Peruvian women.</p
Overview of the Canadian pediatric end-stage renal disease database
<p>Abstract</p> <p>Background</p> <p>Performing clinical research among pediatric end-stage renal disease patients is challenging. Barriers to successful initiation and completion of clinical research projects include small sample sizes and resultant limited statistical power and lack of longitudinal follow-up for hard clinical end-points in most single center studies.</p> <p>Description</p> <p>Existing longitudinal organ failure disease registry and administrative health datasets available within a universal access health care system can be used to study outcomes of end-stage renal disease among pediatric patients in Canada. To construct the Canadian Pediatric End-Stage Renal Disease database, registry data were linked to administrative health data through deterministic linkage techniques creating a research database which consists of socio-demographic variables, clinical variables, all-cause hospitalizations, and relevant outcomes (death and renal allograft loss) for this patient population. The research database also allows study of major cardiovascular events using previously validated administrative data definitions.</p> <p>Conclusion</p> <p>Organ failure registry linked to health administrative data can be a powerful tool to perform longitudinal studies in pediatric end-stage renal disease patients. The rich clinical and demographic information found in this database will facilitate study of important medical and non-medical risk factors for death, graft loss and cardiovascular disease among pediatric end-stage renal disease patients.</p
Consumers of natural health products: natural-born pharmacovigilantes?
<p>Abstract</p> <p>Background</p> <p>Natural health products (NHPs), such as herbal medicines and vitamins, are widely available over-the-counter and are often purchased by consumers without advice from a healthcare provider. This study examined how consumers respond when they believe they have experienced NHP-related adverse drug reactions (ADRs) in order to determine how to improve current safety monitoring strategies.</p> <p>Methods</p> <p>Qualitative semi-structured interviews were conducted with twelve consumers who had experienced a self-identified NHP-related ADR. Key emergent themes were identified and coded using content analysis techniques.</p> <p>Results</p> <p>Consumers were generally not comfortable enough with their conventional health care providers to discuss their NHP-related ADRs. Consumers reported being more comfortable discussing NHP-related ADRs with personnel from health food stores, friends or family with whom they had developed trusted relationships. No one reported their suspected ADR to Health Canada and most did not know this was possible.</p> <p>Conclusion</p> <p>Consumers generally did not report their suspected NHP-related ADRs to healthcare providers or to Health Canada. Passive reporting systems for collecting information on NHP-related ADRs cannot be effective if consumers who experience NHP-related ADRs do not report their experiences. Healthcare providers, health food store personnel, manufacturers and other stakeholders also need to take responsibility for reporting ADRs in order to improve current pharmacovigilance of NHPs.</p
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