23,152 research outputs found
Association between SGLT2 Inhibitors vs DPP-4 Inhibitors and Risk of Pneumonia Among Patients with Type 2 Diabetes
Context:
Patients with diabetes are at a higher risk of pneumonia and pneumonia mortality. Sodium glucose co-transporter 2 inhibitors (SGLT2is), the latest class of glucose-lowering agents, were shown to reduce the risk of pneumonia in clinical trials. However, the real-world effectiveness of SGLT2is on the risk of pneumonia is largely unknown.
Objective:
To investigate the associations between SGLT2is use and the risk of pneumonia and pneumonia mortality compared with dipeptidyl peptidase-4 inhibitors (DPP4is) using an electronic medical database in Hong Kong.
Design
A retrospective cohort study. The “prevalent new-user” design was adopted to account for the previous exposure to the study drugs being compared. Propensity score (PS) matching (1:4) was used to balance the baseline characteristics of the 2 groups.
Setting and participants
Electronic health data of type 2 diabetes patients using SGLT2is and DPP4is between 2015 and 2018 was collected from the Clinical Data Analysis and Reporting System.
Main Outcome Measures:
Pneumonia incidence and mortality.
Results:
The PS-matched cohort consisted of 6664 users of SGLT2is and 26 656 users of DPP4is, with a mean follow-up of 3.8 years. Poisson regression showed that SGLT2is use was associated with lower risk of pneumonia compared with DPP4is with an absolute rate difference of 4.05 per 1000 person-years (95% CI, 2.61-5.51). The corresponding incidence rate ratio was 0.71 (95% CI, 0.62-0.81). Similar reduction in risk of pneumonia death was observed (hazard ratio 0.57; 95% CI, 0.42-0.77).
Conclusion:
Compared with DPP4is, SGLT2is use was associated with a reduced risk of pneumonia and pneumonia mortality in a real-world setting
Spin-Electromagnetic Hydrodynamics and Magnetization Induced by Spin-Magnetic Interaction
The hydrodynamic model including the spin degree of freedom and the
electromagnetic field was discussed. In this derivation, we applied
electromagnetism for macroscopic medium proposed by Minkowski. For the equation
of motion of spin, we assumed that the hydrodynamic representation of the Pauli
equation is reproduced when the many-body effect is neglected. Then the
spin-magnetic interaction in the Pauli equation was converted to a part of the
magnetization. The fluid and spin stress tensors induced by the many-body
effect were obtained by employing the algebraic positivity of the entropy
production in the framework of the linear irreversible thermodynamics,
including the mixing effect of the irreversible currents. We further
constructed the constitutive equation of the polarization and the
magnetization. Our polarization equation is more reasonable compared to another
result obtained using electromagnetism for macroscopic medium proposed by de
Groot-Mazur.Comment: 24 pages, no figure, the discussion for the modifed thermodynamic
relation is added, several errors are corrected, accepted for publication in
PR
Performance evaluation of video streaming on LTE with coexistence of Wi-Fi signal
The continuous growth in mobile data traffic and limited license wireless spectrum have led to dramatically increase the demand of the radio spectrum. It is widespread the concern about the coexistence of long term evolution (LTE) and Wi-Fi in the unlicensed band. There are several techniques have been proposed to enable the coexistence of LTE and Wi-Fi in the unlicensed band, but these works are targeted on the impact of the LTE to the Wi-Fi network performance. An experiment is carried out in this work to evaluate the impact of Wi-Fi signal on the video streaming in the LTE network. The experimental test comprised of the national instrument (NI) universal software radio peripheral (USRP) 2953R that is controlled by the LabVIEW Communication LTE application framework. Extensiveexperiments are carried out under two scenarios, i.e. (1) Coexistence of LTE and Wi-Fi signal, (2) LTE signal only. Performance evaluations are carried out with different Modulation and coding schemes (MCS) values and different mode of operations, i.e. frequency division duplex (FDD) and time division duplex (TDD) mode. The results illustrated that the interference from Wi-Fi signal caused the performance degradation of the LTE network in throughput and the power received by user equipment (UE)
Enhanced exponential rule scheduling algorithm for real-time traffic in LTE network
Nowadays, mobile communication is growing rapidly and become an everyday commodity. The vast deployment of real-time services in Long Term Evolution (LTE) network demands for the scheduling techniques that support the Quality of Service (QoS) requirements. LTE is designed and implemented to fulfill the users’ QoS. However, 3GPP does not define the specific scheduling technique for resource distribution which leads to vast research and development of the scheduling techniques. In this context, a review of the recent scheduling algorithm is reported in the literature. These schedulers in the literature cause high Packet Loss Rate (PLR), low fairness, and high delay. To cope with these disadvantages, we propose an enhanced EXPRULE (eEXPRULE) scheduler to improve the radio resource utilization in the LTE network. Extensive simulation works are carried out and the proposed scheduler provides a significant performance improvement for video application without sacrificing the VoIP performance. The eEXPRULE scheduler increases video throughput, spectrum efficiency, and fairness by 50%, 13%, and 11%, respectively, and reduces the video PLR by 11%
Optimal Resource Allocation in Random Networks with Transportation Bandwidths
We apply statistical physics to study the task of resource allocation in
random sparse networks with limited bandwidths for the transportation of
resources along the links. Useful algorithms are obtained from recursive
relations. Bottlenecks emerge when the bandwidths are small, causing an
increase in the fraction of idle links. For a given total bandwidth per node,
the efficiency of allocation increases with the network connectivity. In the
high connectivity limit, we find a phase transition at a critical bandwidth,
above which clusters of balanced nodes appear, characterised by a profile of
homogenized resource allocation similar to the Maxwell's construction.Comment: 28 pages, 11 figure
Relativistic Modification of the Gamow Factor
In processes involving Coulomb-type initial- and final-state interactions,
the Gamow factor has been traditionally used to take into account these
additional interactions. The Gamow factor needs to be modified when the
magnitude of the effective coupling constant increases or when the velocity
increases. For the production of a pair of particles under their mutual
Coulomb-type interaction, we obtain the modification of the Gamow factor in
terms of the overlap of the Feynman amplitude with the relativistic wave
function of the two particles. As a first example, we study the modification of
the Gamow factor for the production of two bosons. The modification is
substantial when the coupling constant is large.Comment: 13 pages, in LaTe
Effects of CMB temperature uncertainties on cosmological parameter estimation
We estimate the effect of the experimental uncertainty in the measurement of
the temperature of the cosmic microwave background (CMB) on the extraction of
cosmological parameters from future CMB surveys. We find that even for an ideal
experiment limited only by cosmic variance up to l = 2500 for both the
temperature and polarisation measurements, the projected cosmological parameter
errors are remarkably robust against the uncertainty of 1 mK in the FIRAS
instrument's CMB temperature monopole measurement. The maximum degradation in
sensitivity is 20%, for the baryon density estimate, relative to the case in
which the monopole is known infinitely well. While this degradation is
acceptable, we note that reducing the uncertainty in the current temperature
measurement by a factor of five will bring it down to the per cent level. We
also estimate the effect of the uncertainty in the dipole temperature
measurement. Assuming the overall calibration of the data to be dominated by
the dipole error of 0.2% from FIRAS, the sensitivity degradation is
insignificant and does not exceed 10% in any parameter direction.Comment: 12 pages, 2 figures, uses iopart.cls, v2: added discussion of CMB
dipole uncertainty, version accepted by JCA
Theory for a Hanbury Brown Twiss experiment with a ballistically expanding cloud of cold atoms
We have studied one-body and two-body correlation functions in a
ballistically expanding, non-interacting atomic cloud in the presence of
gravity. We find that the correlation functions are equivalent to those at
thermal equilibrium in the trap with an appropriate rescaling of the
coordinates. We derive simple expressions for the correlation lengths and give
some physical interpretations. Finally a simple model to take into account
finite detector resolution is discussed
A factorization of a super-conformal map
A super-conformal map and a minimal surface are factored into a product of
two maps by modeling the Euclidean four-space and the complex Euclidean plane
on the set of all quaternions. One of these two maps is a holomorphic map or a
meromorphic map. These conformal maps adopt properties of a holomorphic
function or a meromorphic function. Analogs of the Liouville theorem, the
Schwarz lemma, the Schwarz-Pick theorem, the Weierstrass factorization theorem,
the Abel-Jacobi theorem, and a relation between zeros of a minimal surface and
branch points of a super-conformal map are obtained.Comment: 21 page
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