100 research outputs found
Equivalent qubit dynamics under classical and quantum noise
We study the dynamics of quantum systems under classical and quantum noise,
focusing on decoherence in qubit systems. Classical noise is described by a
random process leading to a stochastic temporal evolution of a closed quantum
system, whereas quantum noise originates from the coupling of the microscopic
quantum system to its macroscopic environment. We derive deterministic master
equations describing the average evolution of the quantum system under
classical continuous-time Markovian noise and two sets of master equations
under quantum noise. Strikingly, these three equations of motion are shown to
be equivalent in the case of classical random telegraph noise and proper
quantum environments. Hence fully quantum-mechanical models within the Born
approximation can be mapped to a quantum system under classical noise.
Furthermore, we apply the derived equations together with pulse optimization
techniques to achieve high-fidelity one-qubit operations under random telegraph
noise, and hence fight decoherence in these systems of great practical
interest.Comment: 5 pages, 2 figures; converted to PRA format, added Fig. 2, corrected
typo
The Josephson heat interferometer
The Josephson effect represents perhaps the prototype of macroscopic phase
coherence and is at the basis of the most widespread interferometer, i.e., the
superconducting quantum interference device (SQUID). Yet, in analogy to
electric interference, Maki and Griffin predicted in 1965 that thermal current
flowing through a temperature-biased Josephson tunnel junction is a stationary
periodic function of the quantum phase difference between the superconductors.
The interplay between quasiparticles and Cooper pairs condensate is at the
origin of such phase-dependent heat current, and is unique to Josephson
junctions. In this scenario, a temperature-biased SQUID would allow heat
currents to interfere thus implementing the thermal version of the electric
Josephson interferometer. The dissipative character of heat flux makes this
coherent phenomenon not less extraordinary than its electric (non-dissipative)
counterpart. Albeit weird, this striking effect has never been demonstrated so
far. Here we report the first experimental realization of a heat
interferometer. We investigate heat exchange between two normal metal
electrodes kept at different temperatures and tunnel-coupled to each other
through a thermal `modulator' in the form of a DC-SQUID. Heat transport in the
system is found to be phase dependent, in agreement with the original
prediction. With our design the Josephson heat interferometer yields
magnetic-flux-dependent temperature oscillations of amplitude up to ~21 mK, and
provides a flux-to-temperature transfer coefficient exceeding ~ 60mK/Phi_0 at
235 mK [Phi_0 2* 10^(-15) Wb is the flux quantum]. Besides offering remarkable
insight into thermal transport in Josephson junctions, our results represent a
significant step toward phase-coherent mastering of heat in solid-state
nanocircuits, and pave the way to the design of novel-concept coherent
caloritronic devices.Comment: 4+ pages, 3 color figure
The Constitutionalisation of Contract Law in Finland
This chapter discusses the constitutionalisation of Contract law in Finland and makes frequent comparative references to the other Nordic systems. It aims to describe how Constitutional law has gradually started to influence Contract law. Moreover, the analysis seeks to predict some key future developments concerning Constitutional Contract law in Finland. This chapter illustrates how relevant constitutional actors consider these two areas of law and how these actors may sometimes collide because of key doctrines and the constitutional structure. It is concluded that references to Constitutional and Human rights law are not going to replace traditional Contract law argumentation. In most cases, nevertheless, Constitutional and Human rights law offer a useful means to clarify and modify the arguments used in traditional Contract law reasoning. The authors expect growing significance and legal relevance of the relationship between Constitutional law and Contract law.Peer reviewe
Terveydenhuollon palveluvalikoiman priorisointi
Selvityksen tavoitteena on terveydenhuollon priorisoinnin kansallinen kehittäminen. Priorisoinnilla tarkoitetaan tässä yhteydessä kaikkia niitä toimintoja, jotka pyrkivät terveydenhuollon resurssien kohdentamiseen.
Selvityksessä on kuvattu terveydenhuollon priorisoinnin oikeudellisia reunaehtoja sekä haettu tietoa eri maiden priorisoinnin kehittämisestä ja niiden vaikutuksista. Hankkeessa tehtiin myös kyselyjä ja työpajoja eri sidosryhmille.
Suomessa toivotaan kansallisia avoimia ja läpinäkyviä periaatteita priorisoinnin tueksi. Tällä hetkellä kansalaiset ja ammattilaiset eivät hahmota terveyspalvelujen kokonaisuutta ja todellisia kustannuksia. Jotta priorisoinnista tulisi hyväksyttyä, on 1) alettava toteuttaa systemaattista viestintästrategiaa osallistamisen mahdollistamiseksi ja 2) osallistettava eri sidosryhmiä priorisoinnin periaatteiden kehittämiseen. Tämä vaatii myös 3) kansallisten rakenteiden ja prosessien luomista periaatteiden muodostamiseen sekä niiden jalostamiseksi kriteereiksi ja menetelmiksi sekä 4) lainsäädännön kehittämistä.
Perustuslain tulkinnassa on painotettu yksilön oikeuksia. Perustuslaki jättää kuitenkin liikkumavaraa kehittää priorisoinnin oikeudellista ohjausta myös väestöterveyden ja yhteiskunnan taloudelliset voimavarat nykyistä selvemmin huomioon ottavaan suuntaan.Sivua 18 on päivitetty 29.8.2022 ja aineisto korvaa aikaisemmin, 24.8.2022 julkaistun version.
Tämä julkaisu on toteutettu osana valtioneuvoston selvitys- ja tutkimussuunnitelman toimeenpanoa (tietokayttoon.fi). Julkaisun sisällöstä vastaavat tiedon tuottajat, eikä tekstisisältö välttämättä edusta valtioneuvoston näkemystä
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Recessive TMOD1 mutation causes childhood cardiomyopathy.
Familial cardiomyopathy in pediatric stages is a poorly understood presentation of heart disease in children that is attributed to pathogenic mutations. Through exome sequencing, we report a homozygous variant in tropomodulin 1 (TMOD1; c.565C>T, p.R189W) in three individuals from two unrelated families with childhood-onset dilated and restrictive cardiomyopathy. To decipher the mechanism of pathogenicity of the R189W mutation in TMOD1, we utilized a wide array of methods, including protein analyses, biochemistry and cultured cardiomyocytes. Structural modeling revealed potential defects in the local folding of TMOD1R189W and its affinity for actin. Cardiomyocytes expressing GFP-TMOD1R189W demonstrated longer thin filaments than GFP-TMOD1wt-expressing cells, resulting in compromised filament length regulation. Furthermore, TMOD1R189W showed weakened activity in capping actin filament pointed ends, providing direct evidence for the variant's effect on actin filament length regulation. Our data indicate that the p.R189W variant in TMOD1 has altered biochemical properties and reveals a unique mechanism for childhood-onset cardiomyopathy
Recreational and occupational field exposure to freshwater cyanobacteria – a review of anecdotal and case reports, epidemiological studies and the challenges for epidemiologic assessment
Cyanobacteria are common inhabitants of freshwater lakes and reservoirs throughout the world. Under favourable conditions, certain cyanobacteria can dominate the phytoplankton within a waterbody and form nuisance blooms. Case reports and anecdotal references dating from 1949 describe a range of illnesses associated with recreational exposure to cyanobacteria: hay fever-like symptoms, pruritic skin rashes and gastro-intestinal symptoms are most frequently reported. Some papers give convincing descriptions of allergic reactions while others describe more serious acute illnesses, with symptoms such as severe headache, pneumonia, fever, myalgia, vertigo and blistering in the mouth. A coroner in the United States found that a teenage boy died as a result of accidentally ingesting a neurotoxic cyanotoxin from a golf course pond. This death is the first recorded human fatality attributed to recreational exposure to cyanobacteria, although uncertainties surround the forensic identification of the suspected cyanotoxin in this case. We systematically reviewed the literature on recreational exposure to freshwater cyanobacteria. Epidemiological data are limited, with six studies conducted since 1990. Statistically significant increases in symptoms were reported in individuals exposed to cyanobacteria compared to unexposed counterparts in two Australian cohort studies, though minor morbidity appeared to be the main finding. The four other small studies (three from the UK, one Australian) did not report any significant association. However, the potential for serious injury or death remains, as freshwater cyanobacteria under bloom conditions are capable of producing potent toxins that cause specific and severe dysfunction to hepatic or central nervous systems. The exposure route for these toxins is oral, from ingestion of recreational water, and possibly by inhalation. A range of freshwater microbial agents may cause acute conditions that present with features that resemble illnesses attributed to contact with cyanobacteria and, conversely, acute illness resulting from exposure to cyanobacteria or cyanotoxins in recreational waters could be misdiagnosed. Accurately assessing exposure to cyanobacteria in recreational waters is difficult and unreliable at present, as specific biomarkers are unavailable. However, diagnosis of cyanobacteria-related illness should be considered for individuals presenting with acute illness following freshwater contact if a description is given of a waterbody visibly affected by planktonic mass development
Pheromones and Other Semiochemicals for Monitoring Rare and Endangered Species
As global biodiversity declines, biodiversity and conservation have become ever more important research topics. Research in chemical ecology for conservation purposes has not adapted to address this need. During the last 10-15 years, only a few insect pheromones have been developed for biodiversity and conservation studies, including the identification and application of pheromones specifically for population monitoring. These investigations, supplemented with our knowledge from decades of studying pest insects, demonstrate that monitoring with pheromones and other semiochemicals can be applied widely for conservation of rare and threatened insects. Here, I summarize ongoing conservation research, and outline potential applications of chemical ecology and pheromone-based monitoring to studies of insect biodiversity and conservation research. Such applications include monitoring of insect population dynamics and distribution changes, including delineation of current ranges, the tracking of range expansions and contractions, and determination of their underlying causes. Sensitive and selective monitoring systems can further elucidate the importance of insect dispersal and landscape movements for conservation. Pheromone-based monitoring of indicator species will also be useful in identifying biodiversity hotspots, and in characterizing general changes in biodiversity in response to landscape, climatic, or other environmental changes
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