318 research outputs found
The Development of Egalitarianism, Altruism, Spite and Parochialism in Childhood and Adolescence
We study how the distribution of other-regarding preferences develops with age. Based on a set of allocation choices, we can classify each of 717 subjects, aged 8 to 17 years, as either egalitarian, altruistic, or spiteful. Varying the allocation recipient as either an in-group or an out-group member, we can also study how parochialism develops with age. We find a strong decrease in spitefulness with increasing age. Egalitarianism becomes less frequent, and altruism much more prominent, with age. Women are more frequently classified as egalitarian than men, and less often as altruistic. Parochialism first becomes significant in the teenage years.other-regarding preferences, egalitarianism, altruism, spite, parochialism, experiments with children and adolescents
High Resolution Microimaging with Pulsed Electrically-Detected Magnetic Resonance
The investigation of paramagnetic species (such as point defects, dopants,
and impurities) in solid-state electronic devices is significant because of
their effect on device performance. Conventionally, these species are detected
and imaged using the electron spin resonance (ESR) technique. In many
instances, ESR is not sensitive enough to deal with miniature devices having
small numbers of paramagnetic species and high spatial heterogeneity. This
limitation can in principle be overcome by employing a more sensitive method
called electrically-detected magnetic resonance, which is based on measuring
the effect of paramagnetic species on the electric current of the device while
inducing electron spin-flip transitions. However, up until now, measurement of
the current of the device could not reveal the spatial heterogeneity of its
paramagnetic species. We provide here, for the first time, high resolution
microimages of paramagnetic species in operating solar cells obtained through
electrically-detected magnetic resonance. The method is based on unique
microwave pulse sequences for excitation and detection of the electrical signal
under a static magnetic field and powerful pulsed magnetic field gradients that
spatially encode the electrical current of the sample. The approach developed
here can be widely used in the nondestructive three-dimensional inspection and
characterization of paramagnetic species in a variety of electronic devices.Comment: 19 pages, 4 figures +S
Complete Insecurity of Quantum Protocols for Classical Two-Party Computation
A fundamental task in modern cryptography is the joint computation of a
function which has two inputs, one from Alice and one from Bob, such that
neither of the two can learn more about the other's input than what is implied
by the value of the function. In this Letter, we show that any quantum protocol
for the computation of a classical deterministic function that outputs the
result to both parties (two-sided computation) and that is secure against a
cheating Bob can be completely broken by a cheating Alice. Whereas it is known
that quantum protocols for this task cannot be completely secure, our result
implies that security for one party implies complete insecurity for the other.
Our findings stand in stark contrast to recent protocols for weak coin tossing,
and highlight the limits of cryptography within quantum mechanics. We remark
that our conclusions remain valid, even if security is only required to be
approximate and if the function that is computed for Bob is different from that
of Alice.Comment: v2: 6 pages, 1 figure, text identical to PRL-version (but reasonably
formatted
Social preferences in childhood and adolescence. A large-scale experiment to estimate primary and secondary motivations
We elicit social preferences of 883 children and teenagers, aged eight to 17 years, in an experiment. Using an econometric mixture model we estimate a subject\u2019s primary and secondary social preference motivations. The secondary motivation indicates the motivation that becomes relevant when the primary motivation implies indifference between various choices. For girls, particularly older ones, maximin-preferences are the most frequent primary motivation, while for boys efficiency concerns are most relevant. Examining secondary motivations reveals that girls are mostly social-welfare-oriented, with strong equity concerns. Boys are also oriented towards social welfare, but are more concerned with efficiency than with equity
Improved sensitivity of an interferon-gamma release assay (T-SPOT.TB™) in combination with tuberculin skin test for the diagnosis of latent tuberculosis in the presence of HIV co-Infection
BACKGROUND: Interferon-gamma release assays (IGRA) are more specific than the tuberculin skin test (TST) for the diagnosis of Mycobacterium tuberculosis infection. Data on sensitivity are controversial in HIV infection. METHODS: IGRA (T-SPOT.TB) was performed using lymphocytes stored within 6 months before culture-confirmed tuberculosis was diagnosed in HIV-infected individuals in the Swiss HIV Cohort Study. RESULTS: 64 individuals (69% males, 45% of non-white ethnicity, median age 35 years (interquartile range [IQR] 31-42), 28% with prior AIDS) were analysed. Median CD4 cell count was 223 cells/μl (IQR 103-339), HIV-RNA was 4.7 log10 copies/mL (IQR 4.3-5.2). T-SPOT.TB resulted positive in 25 patients (39%), negative in 18 (28%) and indeterminate in 21 (33%), corresponding to a sensitivity of 39% (95% CI 27-51%) if all test results were considered, and 58% (95% CI 43-74%) if indeterminate results were excluded. Sensitivity of IGRA was independent of CD4 cell count (p = 0.698). Among 44 individuals with available TST, 22 (50%) had a positive TST. Agreement between TST and IGRA was 57% (kappa = 0.14, p = 0.177), and in 34% (10/29) both tests were positive. Combining TST and IGRA (at least one test positive) resulted in an improved sensitivity of 67% (95% CI 52-81%). In multivariate analysis, older age was associated with negative results of TST and T-SPOT.TB (OR 3.07, 95% CI 1,22-7.74, p = 0.017, per 10 years older). CONCLUSIONS: T-SPOT.TB and TST have similar sensitivity to detect latent TB in HIV-infected individuals. Combining TST and IGRA may help clinicians to better select HIV-infected individuals with latent tuberculosis who qualify for preventive treatment
A modeling approach to study the effect of cell polarization on keratinocyte migration
The skin forms an efficient barrier against the environment, and rapid
cutaneous wound healing after injury is therefore essential. Healing of the
uppermost layer of the skin, the epidermis, involves collective migration of
keratinocytes, which requires coordinated polarization of the cells. To study
this process, we developed a model that allows analysis of live-cell images of
migrating keratinocytes in culture based on a small number of parameters,
including the radius of the cells, their mass and their polarization. This
computational approach allowed the analysis of cell migration at the front of
the wound and a reliable identification and quantification of the impaired
polarization and migration of keratinocytes from mice lacking fibroblast growth
factors 1 and 2 an established model of impaired healing. Therefore, our
modeling approach is suitable for large-scale analysis of migration phenotypes
of cells with specific genetic defects or upon treatment with different
pharmacological agents.Comment: 27 pages, 3 figure
The development of egalitarianism, altruism, spite and parochialism
Abstract: We study how the distribution of other-regarding preferences develops with age. Based on a set of allocation choices, we classify each of 717 subjects, aged 8 to 17 years, as either egalitarian, altruistic, or spiteful. We find a strong decrease in spitefulness with increasing age. Egalitarianism becomes less frequent, and altruism much more prominent, with age. Females are more frequently classified as egalitarian than males, and less often as altruistic. By varying the allocation recipient as either an in-group or an out-group member, we also study how parochialism develops with age. Parochialism emerges significantly in the teenage years
Lock-in detection for pulsed electrically detected magnetic resonance
We show that in pulsed electrically detected magnetic resonance (pEDMR)
signal modulation in combination with a lock-in detection scheme can reduce the
low-frequency noise level by one order of magnitude and in addition removes the
microwave-induced non-resonant background. This is exemplarily demonstrated for
spin-echo measurements in phosphorus-doped Silicon. The modulation of the
signal is achieved by cycling the phase of the projection pulse used in pEDMR
for the read-out of the spin state.Comment: 4 pages, 2 figure
Survey Evidence on Conditional Norm Enforcement
We discuss survey evidence on individuals' willingness to sanction norm violations - such as evading taxes, drunk driving, fare dodging, or skiving o work - by expressing disapproval or social exclusion. Our data suggest that people condition their sanctioning behavior on their belief about the frequency of norm violations. The more commonly a norm violation is believed to occur, the lower the individuals' inclination to punish it. Based on an instrumental variable approach, we demonstrate that this pattern reflects a causal relationship
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