An experiment to search for light sterile neutrinos is conducted at a reactor with a thermal power of 2.8 GW located at the Hanbit nuclear power complex. The search is done with a detector consisting ...of a ton of Gd-loaded liquid scintillator in a tendon gallery approximately 24 m from the reactor core. The measured antineutrino event rate is 1976 per day with a signal to background ratio of about 22. The shape of the antineutrino energy spectrum obtained from the eight-month data-taking period is compared with a hypothesis of oscillations due to active-sterile antineutrino mixing. No strong evidence of 3+1 neutrino oscillation is found. An excess around the 5 MeV prompt energy range is observed as seen in existing longer-baseline experiments. The mixing parameter sin^{2}2θ_{14} is limited up to less than 0.1 for Δm_{41}^{2} ranging from 0.2 to 2.3 eV^{2} with a 90% confidence level.
A novel concept for integrating visible light communications (VLC) with three‐dimensional indoor positioning is presented. A VLC link based on transmitter and receiver characteristics using ...experimental measurements was modelled. Proposed is a three‐dimensional positioning algorithm using received signal strength indication, which changes based on the angle and distance of the location based service. To reduce inter‐cell interference, the transmitter's location code was sent using different subcarriers. A demonstration shows that the proposed algorithm can obtain a user's position, including height, accurately and without inter‐cell interference.
Merons which are topologically equivalent to one-half of skyrmions can exist only in pairs or groups in two-dimensional (2D) ferromagnetic (FM) systems. The recent discovery of meron lattice in ...chiral magnet Co
Zn
Mn
raises the immediate challenging question that whether a single meron pair, which is the most fundamental topological structure in any 2D meron systems, can be created and stabilized in a continuous FM film? Utilizing winding number conservation, we develop a new method to create and stabilize a single pair of merons in a continuous Py film by local vortex imprinting from a Co disk. By observing the created meron pair directly within a magnetic field, we determine its topological structure unambiguously and explore the topological effect in its creation and annihilation processes. Our work opens a pathway towards developing and controlling topological structures in general magnetic systems without the restriction of perpendicular anisotropy and Dzyaloshinskii-Moriya interaction.
An intensive investigation of carbonaceous PM2.5 and TSP (total suspended particles) from Pudong (China) was conducted as part of the MIRAGE-Shanghai (Megacities Impact on Regional and Global ...Environment) experiment in 2009. Data for organic and elemental carbon (OC and EC), organic species, including C17 to C40 n-alkanes and 17 polycyclic aromatic hydrocarbons (PAHs), and stable carbon isotopes OC (δ13COC) and EC (δ13CEC) were used to evaluate the aerosols' temporal variations and identify presumptive sources. High OC/EC ratios indicated a large fraction of secondary organic aerosol (SOA); high char/soot ratios indicated stronger contributions to EC from motor vehicles and coal combustion than biomass burning. Diagnostic ratios of PAHs indicated that much of the SOA was produced via coal combustion. Isotope abundances (δ13COC = −24.5 ± 0.8‰ and δ13CEC = −25.1 ± 0.6‰) indicated that fossil fuels were the most important source for carbonaceous PM2.5 (particulate matter less than 2.5 micrometers in diameter), with lesser impacts from biomass burning and natural sources. An EC tracer system and isotope mass balance calculations showed that the relative contributions to total carbon from coal combustion, motor vehicle exhaust, and SOA were 41%, 21%, and 31%; other primary sources such as marine, soil and biogenic emissions contributed 7%. Combined analyses of OC and EC, n-alkanes and PAHs, and stable carbon isotopes provide a new way to apportion the sources of carbonaceous particles.
The stress–strain relationship between ferrite and martensite phases in the commercial dual-phase DP980 steel was studied using in situ neutron diffraction and the crystal plasticity finite element ...method (CPFEM). The phase identification method based on the image quality of electron backscatter diffraction and a filtering process was used to obtain information concerning individual crystallographic orientations for ferrite and martensite phases in DP980 steel. The (200) and (211) lattice strains of ferrite and martensite phases were measured along the loading and transverse directions as a function of macroscopic stress using in situ neutron diffraction. A CPFEM based on representative volume elements (RVE) was applied to determine the microscopic hardening parameters for each phase by fitting the measured macroscopic stress and measured (200) and (211) lattice strains. The microscopic hardening parameters for each phase successfully captured the influence of the crystallographic orientation of the ferrite phase on the localization of shear strain and the behavior of ductile failure in RVE of the unit cell during uniaxial tension.
Background
A virtual reality (VR) tour of the operating theatre before anaesthesia could provide a realistic experience for children. This study was designed to determine whether a preoperative VR ...tour could reduce preoperative anxiety in children.
Methods
Children scheduled for elective surgery under general anaesthesia were randomized into a control or VR group. The control group received conventional information regarding anaesthesia and surgery. The VR group watched a 4‐min video showing Pororo, the famous little penguin, visiting the operating theatre and explaining what is in it. The main outcome was preoperative anxiety, assessed using the modified Yale Preoperative Anxiety Scale (m‐YPAS) before entering the operating theatre. Secondary outcomes included induction compliance checklist (ICC) and procedural behaviour rating scale (PBRS) scores during anaesthesia.
Results
A total of 69 children were included in the analysis, 35 in the control group and 34 in the VR group. Demographic data and induction time were similar in the two groups. Children in the VR group had a significantly lower m‐YPAS score than those in the control group (median 31·7 (i.q.r. 23·3–37·9) and 51·7 (28·3–63·3) respectively; P < 0·001). During anaesthesia, the VR group had lower ICC and PBRS scores than the control group.
Conclusion
This preoperative VR tour of the operating theatre was effective in alleviating preoperative anxiety and increasing compliance during induction of anaesthesia in children undergoing elective surgery. Registration number: UMIN000025232 (http://www.umin.ac.jp/ctr).
Reduces anxiety
One of the hallmarks of quantum physics is the generation of non-classical quantum states and superpositions, which has been demonstrated in several quantum systems, including ions, solid-state ...qubits and photons. However, only indirect demonstrations of non-classical states have been achieved in mechanical systems, despite the scientific appeal and technical utility of such a capability
, including in quantum sensing, computation and communication applications. This is due in part to the highly linear response of most mechanical systems, which makes quantum operations difficult, as well as their characteristically low frequencies, which hinder access to the quantum ground state
. Here we demonstrate full quantum control of the mechanical state of a macroscale mechanical resonator. We strongly couple a surface acoustic-wave
resonator to a superconducting qubit, using the qubit to control and measure quantum states in the mechanical resonator. We generate a non-classical superposition of the zero- and one-phonon Fock states and map this and other states using Wigner tomography
. Such precise, programmable quantum control is essential to a range of applications of surface acoustic waves in the quantum limit, including the coupling of disparate quantum systems
.
The possibility of using multi-layer graphene (MLG) particles as reinforcement for enhancing the mechanical properties of Cu matrix composites was explored. The combination of ball milling and ...high-ratio differential speed rolling (HRDSR) techniques was utilized to fabricate the 0.5 and 1vol.% MLG/Cu composites. In the HRDSR-processed composites, the nanosized MLG particles with 5–15nm in diameter were dispersed densely and uniformly in the grain interiors of Cu matrix with a preferred crystallographic relationship of 〈111〉Cu//〈0001〉MLG to the matrix. The conventionally rolled composites with the same contents of MLG, however, contained much lower densities of nanosized MLG particles. This result indicates that the large shear strain induced during HRDSR accelerated breaking up of MLGs into nanosizes and enhanced their dispersion in the matrix. The strength improvement through the addition of MLGs was obvious when HRDSR was used, but it was negligible when conventional rolling was used. The strengthening gained through the homogeneous dispersion of high-density nanosized MLG particles in the HRDSR-processed composites was attributed to Orowan strengthening. This finding is different from the HRDSR-processed carbon-nanotube (CNT)/Cu composites studied in our previous work, in which the grain-size reduction through the addition of CNTs was the major contribution to the strengthening effect.
Objectives
This study aimed to examine the association between statin exposure and dementia risk in individuals with hypercholesterolaemia using data from the NHIS‐HEALS database between 2002 and ...2015.
Methods
Subjects were classified into statin exposure and statin nonexposure groups according to medication possession ratio. Dementia was defined as those with primary diagnostic dementia codes such as F00‐F03, G30, G31.1, G31.9 or G31.82. Cox proportional hazards regression models were adopted after stepwise adjustment for confounders to investigate the prospective association between statin exposure and dementia risk.
Results
During the follow‐up period (median follow‐up 11.7 years), 711 cases of dementia occurred, accounting for 11.5% of the total study population (statin exposure group, 8.2%; statin nonexposure group, 12.9%). Compared to the statin nonexposure group, fully adjusted hazard ratios (HRs) (95% confidence intervals CIs) for overall dementia in the statin exposure group were 0.63 (0.43–0.91) and 0.62 (0.50–0.78) in men and women, respectively. Compared to the statin nonexposure group, the HRs (95% CIs) for Alzheimer’s disease and related dementia, vascular dementia and other types of dementia in the statin exposure group were 0.54 (0.32–0.91), 2.45 (0.69–8.68) and 0.59 (0.32–1.07), respectively, in men and 0.53 (0.38–0.73), 1.29 (0.42–3.96) and 0.70 (0.51–0.96), respectively, in women.
Conclusions
Hypercholesterolaemic individuals exposed to statin had a lower risk of overall dementia and Alzheimer’s disease and related dementia in both sexes, and a lower risk of other types of dementia in women, than subjects who were not exposed to statins.
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