4,803 research outputs found
Protective effect of syringaresinol on rats with diabetic nephropathy via regulation of Nrf2/HO-1 and TGF- β1/Smads pathways
Purpose: To investigate the protective role of syringaresinol in a rat model of diabetic nephropathy (DN).
Methods: Streptozotocin was injected intraperitoneally into rats to establish the diabetic model. Streptozotocin-induced rats were orally administered syringaresinol, and pathological changes in kidneys were assessed using hematoxylin and eosin staining. Enzyme-linked immunosorbent assay (ELISA) was used to determine kidney injury indicators, 24-h urine proteins, blood urea nitrogen (BUN), and serum creatinine (SCR). Blood glucose was measured using a blood glucose meter, while levels of malonaldehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-PX) in kidney were also measured using ELISA.
Results: Pathological changes in the kidneys were observed in rats post-streptozotocin treatment. Administration of syringaresinol reduced the lesion degree, with improved pathological morphology in kidney. Syringaresinol administration significantly attenuated streptozotocin-increased levels of BUN, SCR, 24-h urine protein, and blood glucose (p < 0.01). Streptozotocin-induced oxidative stress, shown by enhanced MDA level and reduced levels of SOD, CAT, and GSH-PX, was reversed in rat kidneys following syringaresinol administration. However, the expression levels of nuclear factor erythropoietin- 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) proteins decreased, while transforming growth factor-beta 1 (TGF-β1) and signal transducer and transcriptional modulator (Smad) 2/3/7 proteins increased in rats post-streptozotocin treatment. Syringaresinol administration reversed the effects of streptozotocin on protein expression of Nrf2, HO-1, TGF-β1, and Smad 2/3/7.
Conclusion: Syringaresinol exerted a protective effect against DN through activation of Nrf2 and inactivation of TGF-β1/Smad pathways. Thus, the compound can potentially be developed for management of diabetic nephropathy
Monitoring coalescence behavior of soft colloidal particles in water by small-angle light scattering
The fractal dimension (D f) of the clusters formed during the aggregation of colloidal systems reflects correctly the coalescence extent among the particles (Gauer et al., Macromolecules 42:9103, 2009). In this work, we propose to use the fast small-angle light scattering (SALS) technique to determine the D f value during the aggregation. It is found that in the diffusion-limited aggregation regime, the D f value can be correctly determined from both the power law regime of the average structure factor of the clusters and the scaling of the zero angle intensity versus the average radius of gyration. The obtained D f value is equal to that estimated from the technique proposed in the above work, based on dynamic light scattering (DLS). In the reaction-limited aggregation (RLCA) regime, due to contamination of small clusters and primary particles, the power law regime of the average structure factor cannot be properly defined for the D f estimation. However, the scaling of the zero angle intensity versus the average radius of gyration is still well defined, thus allowing one to estimate the D f value, i.e., the coalescence extent. Therefore, when the DLS-based technique cannot be applied in the RLCA regime, one can apply the SALS technique to monitor the coalescence extent. Applicability and reliability of the technique have been assessed by applying it to an acrylate copolymer colloi
Extra Dimensions: A View from the Top
In models with compact extra dimensions, where the Standard Model fields are
confined to a 3+1 dimensional hyperplane, the production
cross-section at a hadron collider can receive significant contributions from
multiple exchange of KK modes of the graviton. These are carefully computed in
the well-known ADD and RS scenarios, taking the energy dependence of the sum
over graviton propagators into account. Using data from Run-I of the Tevatron,
95% C.L. bounds on the parameter space of both models are derived. For Run-II
of the Tevatron and LHC, discovery limits are estimated.Comment: Typos corrected, references added. 12 pages, LaTeX, 2 ps figure
Schr\"odinger-Heisenberg Variational Quantum Algorithms
Recent breakthroughs have opened the possibility to intermediate-scale
quantum computing with tens to hundreds of qubits, and shown the potential for
solving classical challenging problems, such as in chemistry and condensed
matter physics. However, the extremely high accuracy needed to surpass
classical computers poses a critical demand to the circuit depth, which is
severely limited by the non-negligible gate infidelity, currently around
0.1-1%. Here, by incorporating a virtual Heisenberg circuit, which acts
effectively on the measurement observables, to a real shallow Schr\"odinger
circuit, which is implemented realistically on the quantum hardware, we propose
a paradigm of Schr\"odinger-Heisenberg variational quantum algorithms to
resolve this problem. We choose a Clifford virtual circuit, whose effect on the
Hamiltonian can be efficiently and classically implemented according to the
Gottesman-Knill theorem. Yet, it greatly enlarges the state expressivity,
realizing much larger unitary t-designs. Our method enables accurate quantum
simulation and computation that otherwise is only achievable with much deeper
and more accurate circuits conventionally. This has been verified in our
numerical experiments for a better approximation of random states and a
higher-fidelity solution to the ground state energy of the XXZ model. Together
with effective quantum error mitigation, our work paves the way for realizing
accurate quantum computing algorithms with near-term quantum devices.Comment: We propose a framework of virtual Heisenberg-circuits-enhanced
variational quantum algorithms, which can noiselessly increase the effective
circuit depth to enlarge the quantum circuit expressivity and find
high-fidelity ground state
All-optical control of thermal conduction in waveguide QED
We investigate the heat conduction between two one-dimension waveguides
intermediated by a Laser-driving atom. The Laser provides the optical control
on the heat conduction. The tunable asymmetric conduction of the heat against
the temperature gradient is realized. Assisted by the modulated Laser, the heat
conduction from either waveguide to the other waveguide can be suppressed.
Meanwhile, the conduction towards the direction opposite to the suppressed one
is gained. The heat currents can be significantly amplified by the energy flow
of the Laser. Moveover, the scheme can act like a heat engine
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