2,333 research outputs found
Quantum Key Distribution with Classical Bob
Secure key distribution among two remote parties is impossible when both are
classical, unless some unproven (and arguably unrealistic)
computation-complexity assumptions are made, such as the difficulty of
factorizing large numbers. On the other hand, a secure key distribution is
possible when both parties are quantum.
What is possible when only one party (Alice) is quantum, yet the other (Bob)
has only classical capabilities? We present a protocol with this constraint,
and prove its robustness against attacks: we prove that any attempt of an
adversary to obtain information (and even a tiny amount of information)
necessarily induces some errors that the legitimate users could notice.Comment: 4 and a bit pages, 1 figure, RevTe
Prospective Evaluation of the Ultrasound Signs Proposed for the Description of Uterine Niche in Nonpregnant Women
OBJECTIVES: To evaluate the new ultrasound-based signs for the diagnosis of post-cesarean section uterine niche in nonpregnant women. METHODS: We investigated prospectively a cohort of 160 consecutive women with one previous term cesarean delivery (CD) between December 2019 and 2020. All women were separated into two subgroups according to different stages of labor at the time of their CD: subgroup A (n = 109; 68.1%) for elective CD and CD performed in latent labor at a cervical dilatation (≤4 cm) and subgroup B (n = 51; 31.9%); for CD performed during the active stage of labor (>4 cm). RESULTS: Overall, the incidence of a uterine niche was significantly (P 3 mm in subgroup A than in subgroup B and a significant negative relationship was found between the RMT and the cervical dilatation at CD (r = -0.22; P = .008). CONCLUSIONS: Sonographic cesarean section scar assessment indicates that the type of CD and the stage of labor at which the hysterotomy is performed have an impact on the location of the scar and the scarification process including the niche formation and RMT
Proof of principle of a high-spatial-resolution, resonant-response gamma-ray detector for Gamma Resonance Absorption in 14N
The development of a mm-spatial-resolution, resonant-response detector based
on a micrometric glass capillary array filled with liquid scintillator is
described. This detector was developed for Gamma Resonance Absorption (GRA) in
14N. GRA is an automatic-decision radiographic screening technique that
combines high radiation penetration (the probe is a 9.17 MeV gamma ray) with
very good sensitivity and specificity to nitrogenous explosives. Detailed
simulation of the detector response to electrons and protons generated by the
9.17 MeV gamma-rays was followed by a proof-of-principle experiment, using a
mixed gamma-ray and neutron source. Towards this, a prototype capillary
detector was assembled, including the associated filling and readout systems.
Simulations and experimental results indeed show that proton tracks are
distinguishable from electron tracks at relevant energies, on the basis of a
criterion that combines track length and light intensity per unit length.Comment: 18 pages, 16 figure
Design approaches in technology enhanced learning
Design is a critical to the successful development of any interactive learning environment (ILE). Moreover, in technology enhanced learning (TEL), the design process requires input from many diverse areas of expertise. As such, anyone undertaking tool development is required to directly address the design challenge from multiple perspectives. We provide a motivation and rationale for design approaches for learning technologies that draws upon Simon's seminal proposition of Design Science (Simon, 1969). We then review the application of Design Experiments (Brown, 1992) and Design Patterns (Alexander et al., 1977) and argue that a patterns approach has the potential to address many of the critical challenges faced by learning technologists
A review, timeline, and categorization of learning design tools
Enabling teachers to define or portray efficient teaching ideas for
sharing, reuse or adaptation has attracted the interest of Learning Design
researchers and has led to the development of a variety of learning design tools.
In this paper, we introduce a multi-dimensional framework for the analysis of
learning design tools and use it to review twenty-nine tools currently available to
researchers and practitioners. Lastly, we categorise these tools according to the
main functionality that they offer
Effect of the National Resident Assessment Instrument on Selected Health Conditions and Problems
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111253/1/j.1532-5415.1997.tb02972.x.pd
Signal and Noise Analysis in TRION -Time-Resolved Integrative Optical Fast Neutron Detector
TRION is a sub-mm spatial resolution fast neutron imaging detector, which
employs an integrative optical time-of-flight technique. The detector was
developed for fast neutron resonance radiography, a method capable of detecting
a broad range of conventional and improvised explosives. In this study we have
analyzed in detail, using Monte-Carlo calculations and experimentally
determined parameters, all the processes that influence the signal and noise in
the TRION detector. In contrast to event-counting detectors where the
signal-to-noise ratio is dependent only on the number of detected events
(quantum noise), in an energy-integrating detector additional factors, such as
the fluctuations in imparted energy, number of photoelectrons, system gain and
other factors will contribute to the noise. The excess noise factor (over the
quantum noise) due to these processes was 4.3, 2.7, 2.1, 1.9 and 1.9 for
incident neutron energies of 2, 4, 7.5, 10 and 14 MeV, respectively. It is
shown that, even under ideal light collection conditions, a fast neutron
detection system operating in an integrative mode cannot be
quantum-noise-limited due to the relatively large variance in the imparted
proton energy and the resulting scintillation light distributions.Comment: 18 page
High Spatial Resolution Fast-Neutron Imaging Detectors for Pulsed Fast-Neutron Transmission Spectroscopy
Two generations of a novel detector for high-resolution transmission imaging
and spectrometry of fast-neutrons are presented. These devices are based on a
hydrogenous fiber scintillator screen and single- or multiple-gated intensified
camera systems (ICCD). This detector is designed for energy-selective neutron
radiography with nanosecond-pulsed broad-energy (1 - 10 MeV) neutron beams.
Utilizing the Time-of-Flight (TOF) method, such a detector is capable of
simultaneously capturing several images, each at a different neutron energy
(TOF). In addition, a gamma-ray image can also be simultaneously registered,
allowing combined neutron/gamma inspection of objects. This permits combining
the sensitivity of the fast-neutron resonance method to low-Z elements with
that of gamma radiography to high-Z materials.Comment: Also published in JINST:
http://www.iop.org/EJ/abstract/1748-0221/4/05/P0501
Does the bilingual advantage extend to trilingualism?
YesThis study examined whether the proposed bilingual advantage in inhibitory control and working memory can be extended to a trilingual advantage, and assessed any age-related effects on a continuum in young adults to older adults. Trilinguals, bilinguals and monolinguals’ performance on the Simon task and a numerical version of the N-back task was compared. On the Simon task, there was no language group difference observed, although the data show an age-related decline in inhibitory control only in trilinguals, but not in bilinguals or monolinguals. No clear language group differences were observed between trilinguals and bilinguals on the N-back task, however an overall trilingual and bilingual disadvantage, compared to monolinguals, was observed. Together the results suggest that managing two or three languages, compared to just one, may have a negative impact on inhibitory control and working memory performance. Importantly, they highlight the need to control for a possible confounding effect of including trilinguals/multilinguals in bilingual cohorts and to ensure that participants in monolingual cohorts speak only one language
Association of the Resident Assessment Instrument (RAI) with Changes in Function, Cognition, and Psychosocial Status
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111069/1/j.1532-5415.1997.tb02971.x.pd
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