19,206 research outputs found
Thermodynamic properties of spin-1/2 transverse XY chain with Dzyaloshinskii-Moriya interaction: Exact solution for correlated Lorentzian disorder
We extend the consideration of the spin-1/2 transverse XY chain with
correlated Lorentzian disorder (Phys. Rev. B {\bf 55,} 14298 (1997)) for the
case of additional Dzyaloshinskii-Moriya interspin interaction. It is shown how
the averaged density of states can be calculated exactly. Results are presented
for the density of states and the transverse magnetization.Comment: 2 figure
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Noise performance of microwave humidity sounders over their lifetime
The microwave humidity sounders Special Sensor Microwave Water Vapor Profiler (SSMT-2), Advanced Microwave Sounding Unit-B (AMSU-B) and Microwave Humidity Sounder (MHS) to date have been providing data records for 25 years. So far, the data records lack uncertainty information essential for constructing consistent long time data series. In this study, we assess the quality of the recorded data with respect to the uncertainty caused by noise. We calculate the noise on the raw calibration counts from the deep space views (DSVs) of the instrument and the noise equivalent differential temperature (NEΔT) as a measure for the radiometer sensitivity. For this purpose, we use the Allan deviation that is not biased from an underlying varying mean of the data and that has been suggested only recently for application in atmospheric remote sensing. Moreover, we use the bias function related to the Allan deviation to infer the underlying spectrum of the noise. As examples, we investigate the noise spectrum in flight for some instruments. For the assessment of the noise evolution in time, we provide a descriptive and graphical overview of the calculated NEΔT over the life span of each instrument and channel. This overview can serve as an easily accessible information for users interested in the noise performance of a specific instrument, channel and time. Within the time evolution of the noise, we identify periods of instrumental degradation, which manifest themselves in an increasing NEΔT, and periods of erratic behaviour, which show sudden increases of NEΔT interrupting the overall smooth evolution of the noise. From this assessment and subsequent exclusion of the aforementioned periods, we present a chart showing available data records with NEΔT  <  1 K. Due to overlapping life spans of the instruments, these reduced data records still cover without gaps the time since 1994 and may therefore serve as a first step for constructing long time series. Our method for count noise estimation, that has been used in this study, will be used in the data processing to provide input values for the uncertainty propagation in the generation of a new set of Fundamental Climate Data Records (FCDRs) that are currently produced in the project Fidelity and Uncertainty in Climate data records from Earth Observation (FIDUCEO)
Chronic kidney disease is the major cause of death in Uddanam: a population-representative study using Smart Verbal Autopsy.
Introduction: Uddanam is an agricultural area with a high burden of chronic kidney disease of unknown aetiology (CKDu). Despite reports of many deaths due to CKD in the lay press, the exact contribution of CKD to deaths remains uncertain as most deaths occur outside medical care. Methods: We used SmartVA automated verbal autopsy (VA) tool to ascertain the cause-specific mortality fractions amongst a 2419 subject-strong general population cohort in Uddanam between 2018-2022. VA interviews were conducted twice with the family members of the deceased. Results: A total of 133 deaths were recorded, giving a crude death rate of 5.5%, 10 times higher than that recorded in national surveys. CKD was responsible for 45% of all deaths, followed by ischemic heart disease (15%) and respiratory disease (6%). Conclusion: This study confirms CKD as the leading cause of mortality in this high CKD burden area and provides crucial data for public health decision-making and resource allocation
The Jurisprudential Issues Arising from Legal Transplant: An Appraisal
The paper appraises the jurisprudential issues arising from legal transplant generally. Based on the appraisal it was established that the Jews who moved to Egypt was known to have been the first group of people to have transplanted their laws, values and culture voluntarily without the prompting of the host Country Egypt and while leaving after 43o years of sojourn they left with their laws, values and culture to the promised land. The paper also discovers that Roman laws were one of the initial laws that preceded and was eventually transplanted to the most the European Countries such as Germany, England, Jewish State of Israel, Portugal, French, Dutch and their colonized territories and American colonies and uninhabited areas where it was established through the activities these countries and members of the academic community who have embraced these laws in Europe. The paper further appraises of some foreign religions and laws such as Islamic religion and laws, Hindus laws, common law on the countries they have been transplanted. In conclusion the paper was to note that the following factors, Objective, Political, Cultural, Economy, Chance, Literary factors and Centres of law propagation namely the courts, the bar and the law schools are responsible for transplantation. Keywords: Jurisprudential issues, legal transplant, Roman laws, foreign religion
Foam-like compression behavior of fibrin networks
The rheological properties of fibrin networks have been of long-standing
interest. As such there is a wealth of studies of their shear and tensile
responses, but their compressive behavior remains unexplored. Here, by
characterization of the network structure with synchronous measurement of the
fibrin storage and loss moduli at increasing degrees of compression, we show
that the compressive behavior of fibrin networks is similar to that of cellular
solids. A non-linear stress-strain response of fibrin consists of three
regimes: 1) an initial linear regime, in which most fibers are straight, 2) a
plateau regime, in which more and more fibers buckle and collapse, and 3) a
markedly non-linear regime, in which network densification occurs {{by bending
of buckled fibers}} and inter-fiber contacts. Importantly, the spatially
non-uniform network deformation included formation of a moving "compression
front" along the axis of strain, which segregated the fibrin network into
compartments with different fiber densities and structure. The Young's modulus
of the linear phase depends quadratically on the fibrin volume fraction while
that in the densified phase depends cubically on it. The viscoelastic plateau
regime corresponds to a mixture of these two phases in which the fractions of
the two phases change during compression. We model this regime using a
continuum theory of phase transitions and analytically predict the storage and
loss moduli which are in good agreement with the experimental data. Our work
shows that fibrin networks are a member of a broad class of natural cellular
materials which includes cancellous bone, wood and cork
Investigations into the Applications of Electrospray
The focus of the research is testing of an electrospray platform which will be employed to deposit uniform coatings of carbon nanomaterials to large surfaces. Electrospray, also known as electrohydrodynamic spray or e-spray, is a liquid atomization technique that can generate fine droplets to produce coatings with a high degree of uniformity. The carbon nanotubes (CNTs) and graphene dispersions in water are particularly attractive due to their bulk processing, ease of storage, freedom for tuning the concentration, and for their potential aerospace applications. This electrospray platform will be used to apply CNT films, with varying quantities of graphene that will carry a charge across non-conductive surfaces to act as a de-icing element for aircraft and spacecraft structures. The characterization methods include several measurements of surface roughness and toughness, scanning electron microscope images, surface resistance, and transmittance of the films. So far preliminary testing of voltage for Taylor cone formation of spray has been found at 6,000V potential difference between our spray tip and substrate with a flow rate of 0.1 ml/min. It was observed that the Taylor cone was formed larger drops at lower voltages. The future studies include testing with a stable voltage source
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