3,012 research outputs found
The Optimal Single Copy Measurement for the Hidden Subgroup Problem
The optimization of measurements for the state distinction problem has
recently been applied to the theory of quantum algorithms with considerable
successes, including efficient new quantum algorithms for the non-abelian
hidden subgroup problem. Previous work has identified the optimal single copy
measurement for the hidden subgroup problem over abelian groups as well as for
the non-abelian problem in the setting where the subgroups are restricted to be
all conjugate to each other. Here we describe the optimal single copy
measurement for the hidden subgroup problem when all of the subgroups of the
group are given with equal a priori probability. The optimal measurement is
seen to be a hybrid of the two previously discovered single copy optimal
measurements for the hidden subgroup problem.Comment: 8 pages. Error in main proof fixe
Mutual trust is a prerequisite for nursesâ sense of safety and work satisfaction â Mobile Integrated Care Model: A qualitative interview study
An increasing number of older persons have complex health care needs. This, along with the organizational principle of remaining at home, emphasizes the need to develop collaborations among organizations caring for older persons. A health care model developed in Sweden, the Mobile Integrated Care Model aims to promote work in teams across organizations. The aim of the study was to describe nursesâ experiences in working and providing health care in the Mobile Integrated Care Model in the home with home health care physicians. Semi-structured interviews were conducted with 18 nurses and analyzed through qualitative content analysis. The method was compliant with the COREQ checklist. A mutually trusting collaboration with physicians, which formed person-centered care, created work satisfaction for the nurses. Working within the Mobile Integrated Care Model was negatively impacted by being employed by different organizations, lack of time to provide health care, and physiciansâ person-centered work abilities
The role of the home health care physician in mobile integrated care: a qualitative phenomenograpic study
Background: An increasing older population, along with the organizational principle of remaining at home, has moved health care from institutions into the older personâs home, where several health care providers facilitate care. The Mobile Integrated Care Model strives to provide cost-efficient, coherent, person-centered health care in the home. In the integrated care team, where the home health care physician is the medical authority, several health care professions work across organizational borders. Therefore, the aim of this study was to describe Home Health Care Physicians perceptions of working and providing health care in the Mobile Integrated Care Model, as well as perceptions of participating in and forming health care.
Methods: A phenomenographic qualitative study design, with semi-structured interviews using an interview guide.
Results: Working within Mobile Integrated Care Model was a different way of working as a physician. The physiciansâ role was to support the patient by making safe medical decisions. Physicians described themselves as a piece in the team puzzle, where the professional knowledge of others was crucial to give quality health care. Being in the patientsâ homes was expressed as adding a unique dimension in the provision of health care, and the physicians learned more about the patients by meeting them in their homes than at an institution. This aided the physicians in respecting patient autonomy in medical decision making, even though the physicians sometimes disregarded patient autonomy in favor of their own medical experience. There was a divided view on next of kin participation among the home health care physicians, ranging from always including to total absence of involving next of kin in decision making.
Conclusions: The home health care physicians described the Mobile Integrated Care Model as the best way to work, but there was still a need for additional resources and structure when working in different organizations. The need for full-time employment, additional time or hours, more equipment, access to each otherâs medical records, and additional collaboration with other health care providers were expressed, which could contribute to increased work satisfaction and facilitate further development of person-centered care in the Mobile Integrated Care Model
An efficient quantum algorithm for the hidden subgroup problem in extraspecial groups
Extraspecial groups form a remarkable subclass of p-groups. They are also
present in quantum information theory, in particular in quantum error
correction. We give here a polynomial time quantum algorithm for finding hidden
subgroups in extraspecial groups. Our approach is quite different from the
recent algorithms presented in [17] and [2] for the Heisenberg group, the
extraspecial p-group of size p3 and exponent p. Exploiting certain nice
automorphisms of the extraspecial groups we define specific group actions which
are used to reduce the problem to hidden subgroup instances in abelian groups
that can be dealt with directly.Comment: 10 page
ARIS-Campaign: intercomparison of three ground based 22 GHz radiometers for middle atmospheric water vapor at the Zugspitze in winter 2009
This paper presents the Alpine Radiometer Intercomparison at the Schneefernerhaus (ARIS), which took place in winter 2009 at the high altitude station at the Zugspitze, Germany (47.42° N, 10.98° E, 2650 m). This campaign was the first direct intercomparison between three new ground based 22 GHz water vapor radiometers for middle atmospheric profiling with the following instruments participating: MIRA 5 (Karlsruhe Institute of Technology), cWASPAM3 (Max Planck Institute for Solar System Research, Katlenburg-Lindau) and MIAWARA-C (Institute of Applied Physics, University of Bern). Even though the three radiometers all measure middle atmospheric water vapor using the same rotational transition line and similar fundamental set-ups, there are major differences between the front ends, the back ends, the calibration concepts and the profile retrieval. The spectrum comparison shows that all three radiometers measure spectra without severe baseline artifacts and that the measurements are in good general agreement. The measurement noise shows good agreement to the values theoretically expected from the radiometer noise formula. At the same time the comparison of the noise levels shows that there is room for instrumental and calibration improvement, emphasizing the importance of low elevation angles for the observation, a low receiver noise temperature and an efficient calibration scheme. <br><br> The comparisons of the retrieved profiles show that the agreement between the profiles of MIAWARA-C and cWASPAM3 with the ones of MLS is better than 0.3 ppmv (6%) at all altitudes. MIRA 5 has a dry bias of approximately 0.5 ppm (8%) below 0.1 hPa with respect to all other instruments. The profiles of cWASPAM3 and MIAWARA-C could not be directly compared because the vertical region of overlap was too small. The comparison of the time series at different altitude levels show a similar evolution of the H<sub>2</sub>O volume mixing ratio (VMR) for the ground based instruments as well as the space borne sensor MLS
Combining information from surveys of several species to estimate the probability of freedom from Echinococcus multilocularis in Sweden, Finland and mainland Norway
<p>Abstract</p> <p>Background</p> <p>The fox tapeworm <it>Echinococcus multilocularis </it>has foxes and other canids as definitive host and rodents as intermediate hosts. However, most mammals can be accidental intermediate hosts and the larval stage may cause serious disease in humans. The parasite has never been detected in Sweden, Finland and mainland Norway. All three countries require currently an anthelminthic treatment for dogs and cats prior to entry in order to prevent introduction of the parasite. Documentation of freedom from <it>E. multilocularis </it>is necessary for justification of the present import requirements.</p> <p>Methods</p> <p>The probability that Sweden, Finland and mainland Norway were free from <it>E. multilocularis </it>and the sensitivity of the surveillance systems were estimated using scenario trees. Surveillance data from five animal species were included in the study: red fox (<it>Vulpes vulpes</it>), raccoon dog (<it>Nyctereutes procyonoides</it>), domestic pig, wild boar (<it>Sus scrofa</it>) and voles and lemmings (Arvicolinae).</p> <p>Results</p> <p>The cumulative probability of freedom from EM in December 2009 was high in all three countries, 0.98 (95% CI 0.96-0.99) in Finland and 0.99 (0.97-0.995) in Sweden and 0.98 (0.95-0.99) in Norway.</p> <p>Conclusions</p> <p>Results from the model confirm that there is a high probability that in 2009 the countries were free from <it>E. multilocularis</it>. The sensitivity analyses showed that the choice of the design prevalences in different infected populations was influential. Therefore more knowledge on expected prevalences for <it>E. multilocularis </it>in infected populations of different species is desirable to reduce residual uncertainty of the results.</p
Older personsâ experiences of Reflective STRENGTHâGiving Dialogues â âIt\u27s a push to move forwardâ
Rationale: Experiences of the innovative method Reflective STRENGTHâGiving Dialogue (STRENGTH), which is grounded in a lifeworld perspective and developed to improve quality of care, is described in this study. Innovative thinking in developing health and social care, which may include digital solutions, is required to ensure a meaningful and dignified life in old age.
Aim: The aim of this study was to describe experiences of the intervention Reflective STRENGTHâGiving Dialogue from the perspective of older persons living with longâterm health problems.
Method: Individual qualitative interviews were conducted with 27 older persons who participated in the intervention. The older persons wrote notes from each dialogue in booklets, and the booklets became part of the study data, analysed with a Reflective Lifeworld Research approach.
Results: STRENGTH is experienced as an opportunity to reflect upon life and identify small and large life projects. Dialogues that lead to change in thoughts and actions influence the older persons\u27 wellâbeing, sense of balance, joy and meaning in life. There is an experience of STRENGTH as a starting point and a push to move forward in an effort to experience joy and meaning in life when living with longâterm health problems.
Conclusions: STRENGTH has the potential to contribute to quality improvement in personâcentred care and enhance meaning in life for older persons living with longâterm health problems. However, the use of a digital tool in this particular context poses challenges that must be considered
Computational Indistinguishability between Quantum States and Its Cryptographic Application
We introduce a computational problem of distinguishing between two specific
quantum states as a new cryptographic problem to design a quantum cryptographic
scheme that is "secure" against any polynomial-time quantum adversary. Our
problem, QSCDff, is to distinguish between two types of random coset states
with a hidden permutation over the symmetric group of finite degree. This
naturally generalizes the commonly-used distinction problem between two
probability distributions in computational cryptography. As our major
contribution, we show that QSCDff has three properties of cryptographic
interest: (i) QSCDff has a trapdoor; (ii) the average-case hardness of QSCDff
coincides with its worst-case hardness; and (iii) QSCDff is computationally at
least as hard as the graph automorphism problem in the worst case. These
cryptographic properties enable us to construct a quantum public-key
cryptosystem, which is likely to withstand any chosen plaintext attack of a
polynomial-time quantum adversary. We further discuss a generalization of
QSCDff, called QSCDcyc, and introduce a multi-bit encryption scheme that relies
on similar cryptographic properties of QSCDcyc.Comment: 24 pages, 2 figures. We improved presentation, and added more detail
proofs and follow-up of recent wor
A First Search for Cosmogenic Neutrinos with the ARIANNA Hexagonal Radio Array
The ARIANNA experiment seeks to observe the diffuse flux of neutrinos in the
10^8 - 10^10 GeV energy range using a grid of radio detectors at the surface of
the Ross Ice Shelf of Antarctica. The detector measures the coherent Cherenkov
radiation produced at radio frequencies, from about 100 MHz to 1 GHz, by
charged particle showers generated by neutrino interactions in the ice. The
ARIANNA Hexagonal Radio Array (HRA) is being constructed as a prototype for the
full array. During the 2013-14 austral summer, three HRA stations collected
radio data which was wirelessly transmitted off site in nearly real-time. The
performance of these stations is described and a simple analysis to search for
neutrino signals is presented. The analysis employs a set of three cuts that
reject background triggers while preserving 90% of simulated cosmogenic
neutrino triggers. No neutrino candidates are found in the data and a
model-independent 90% confidence level Neyman upper limit is placed on the all
flavor neutrino+antineutrino flux in a sliding decade-wide energy bin. The
limit reaches a minimum of 1.9x10^-23 GeV^-1 cm^-2 s^-1 sr^-1 in the 10^8.5 -
10^9.5 GeV energy bin. Simulations of the performance of the full detector are
also described. The sensitivity of the full ARIANNA experiment is presented and
compared with current neutrino flux models.Comment: 22 pages, 22 figures. Published in Astroparticle Physic
Performance of the ARIANNA Hexagonal Radio Array
Installation of the ARIANNA Hexagonal Radio Array (HRA) on the Ross Ice Shelf
of Antarctica has been completed. This detector serves as a pilot program to
the ARIANNA neutrino telescope, which aims to measure the diffuse flux of very
high energy neutrinos by observing the radio pulse generated by
neutrino-induced charged particle showers in the ice. All HRA stations ran
reliably and took data during the entire 2014-2015 austral summer season. A new
radio signal direction reconstruction procedure is described, and is observed
to have a resolution better than a degree. The reconstruction is used in a
preliminary search for potential neutrino candidate events in the data from one
of the newly installed detector stations. Three cuts are used to separate radio
backgrounds from neutrino signals. The cuts are found to filter out all data
recorded by the station during the season while preserving 85.4% of simulated
neutrino events that trigger the station. This efficiency is similar to that
found in analyses of previous HRA data taking seasons.Comment: Proceedings from the 34th ICRC2015, http://icrc2015.nl/ . 8 pages, 6
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