1,339 research outputs found
Gastrodia elata powder capsule enhances anti-epileptic effect of carbamazepine by decreasing P-gp expression
Purpose: To investigate the influence of Gastrodia elata powder capsule (GC) or gastrodin (GTD) on the anti-epileptic effect of carbamazepine (CBZ) on penicillin (PG)-induced epilepsy in rats.
Methods: A total 116 rats were used in this study. Rats in the control group (n = 8) were injected with normal saline (NS) in place PG. Epilepsy was induced in the remaining 108 rats on the first day via PG injection. The rats were then divided randomly into six groups (18 rats per group): PG group, CBZ group, CBZ + GC group, CBZ + GTD group, GC group, and GTD group, which were given (p.o.) NS, CBZ (100 mg/kg), CBZ (100 mg/kg.) + GC (350 mg/kg), CBZ (100 mg/kg) + GTD (100 mg/kg), GC (350 mg/kg), and GTD (100 mg/kg), respectively, once a day for 15 days. The behavioral characteristics of the rats were observed and used to assess the anti-epileptic effect of the test drugs. Real-time quantitative reverse transcription-PCR and Western blot assays were employed for the determination of the effect of CBZ, GC and GTD on the expression levels of P-gp.
Results: CBZ significantly reduced the symptoms of epilepsy, while GC and GTD enhanced the antiepileptic effect of CBZ, and reversed the CBZ-induced increases in the protein expressions of mrd1a and P-gp (p < 0.05).
Conclusion: GC reverses CBZ drug resistance, probably through downregulation of P-gp expression. This finding indicates that GC is a potential anti-epilepsy drug, but it merits further studies
Temperature-dependent performance of amorphous silicon photovoltaic/thermal systems in the long term operation
The influences of temperature on the performance of amorphous silicon (a-Si) solar cells and photovoltaic (PV) systems are extensively studied in the literature. The benefit from thermal annealing effect at a higher temperature than ambient has been demonstrated, which makes a-Si cells a promising material for photovoltaic/thermal (PV/T) system. However, the temperature-dependent performance of a-Si PV/T system in the long term operation has rarely been reported. The temperature effect will be more complicated than that on a single cell or PV system. Particularly, the exergetic efficiency and mechanical behavior of the PV/T system at different temperatures are unknown. To fill the above knowledge gap, two identical a-Si PV/T systems are developed. One operates at a water inlet temperature of 60 °C with an a-Si cell temperature of up to 70 °C. The other operates at an inlet temperature of 30 °C. Long-term outdoor tests from December 2017 to June 2019 have been conducted. Results indicate that the difference in the electrical efficiency between the two systems is 0.47% in the initial stage, and it gradually narrows to only 0.13% over time. The overall exergy efficiency at 60 °C generally exceeds that at 30 °C, which proves the superiority of the a-Si PV/T operating at medium temperature. Besides, the long-term operation at 60 °C has not led to a lower level of reliability
How to Face COVID-19 in Ophthalmology Practice
Background: The novel coronavirus pneumonia has attracted considerable attention from the international community. With the spread of outbreaks around the world, the WHO characterized COVID-19 as a pandemic.
Methods: Relevant studies in PubMed were searched from January 1, 2020 to April 12, 2020, using the following search strategy: (“novel coronavirus pneumonia†OR “severe acute respiratory syndrome coronavirus 2†OR “coronavirus disease 2019†OR “COVID-19†OR “novel coronavirus pneumoniaâ€) AND (“ophthalmology†OR “ophthalmologist†OR “eye†OR “conjunctiva†OR “conjunctivitis†OR “corneal†OR “keratitisâ€).
Results: SARS-CoV-2 can spread through aerosol and is detected in tears of patients with COVID-19 infection. Notably, some infected patients had conjunctivitis, and conjunctivitis was the first symptom in some patients later diagnosed to have COVID-19 infection. This would increase the risk for ophthalmologists through inpatient consultations or regular clinical practice. When dealing with seemingly regular ophthalmic patients, the vigilance of ophthalmologists and associated staff tends to be reduced.
Conclusion: Ophthalmologists must continuously update their knowledge regarding COVID-19 and take effective measures to prevent COVID-19 transmission
Transfer Learning in General Lensless Imaging through Scattering Media
Recently deep neural networks (DNNs) have been successfully introduced to the
field of lensless imaging through scattering media. By solving an inverse
problem in computational imaging, DNNs can overcome several shortcomings in the
conventional lensless imaging through scattering media methods, namely, high
cost, poor quality, complex control, and poor anti-interference. However, for
training, a large number of training samples on various datasets have to be
collected, with a DNN trained on one dataset generally performing poorly for
recovering images from another dataset. The underlying reason is that lensless
imaging through scattering media is a high dimensional regression problem and
it is difficult to obtain an analytical solution. In this work, transfer
learning is proposed to address this issue. Our main idea is to train a DNN on
a relatively complex dataset using a large number of training samples and
fine-tune the last few layers using very few samples from other datasets.
Instead of the thousands of samples required to train from scratch, transfer
learning alleviates the problem of costly data acquisition. Specifically,
considering the difference in sample sizes and similarity among datasets, we
propose two DNN architectures, namely LISMU-FCN and LISMU-OCN, and a balance
loss function designed for balancing smoothness and sharpness. LISMU-FCN, with
much fewer parameters, can achieve imaging across similar datasets while
LISMU-OCN can achieve imaging across significantly different datasets. What's
more, we establish a set of simulation algorithms which are close to the real
experiment, and it is of great significance and practical value in the research
on lensless scattering imaging. In summary, this work provides a new solution
for lensless imaging through scattering media using transfer learning in DNNs
Feasibility of an innovative amorphous silicon photovoltaic/thermal system for medium temperature applications
Medium temperature photovoltaic/thermal (PV/T) systems have immense potential in the applications of absorption cooling, thermoelectric generation, and organic Rankine cycle power generation, etc. Amorphous silicon (a-Si) cells are promising in such applications regarding the low temperature coefficient, thermal annealing effect, thin film and avoidance of large thermal stress and breakdown at fluctuating temperatures. However, experimental study on the a-Si PV/T system is rarely reported. So far the feasibility of medium temperature PV/T systems using a-Si cells has not been demonstrated. In this study, the design and construction of an innovative a-Si PV/T system of stainless steel substrate are presented. Long-term outdoor performance of the system operating at medium temperature has been monitored in the past 15 months. The average electrical efficiency was 5.65%, 5.41% and 5.30% at the initial, intermediate and final phases of the long-test test, accompanied with a daily average thermal efficiency from about 21% to 31% in the non-heating season. The thermal and electrical performance of the system at 60 °C, 70 °C and 80 °C are also analyzed and compared. Moreover, a distributed parameter model with experimental validation is developed for an inside view of the heat transfer and power generation and to predict the system performance in various conditions. Technically, medium temperature operation has not resulted in interruption or observable deformation of the a-Si PV/T system during the period. The technical and thermodynamic feasibility of the a-Si PV/T system at medium operating temperature is demonstrated by the experimental and simulation results
Diffraction-Free Bloch Surface Waves
In this letter, we demonstrate a novel diffraction-free Bloch surface wave
(DF-BSW) sustained on all-dielectric multilayers that does not diffract after
being passed through three obstacles or across a single mode fiber. It can
propagate in a straight line for distances longer than 110 {\mu}m at a
wavelength of 633 nm and could be applied as an in-plane optical virtual probe,
both in air and in an aqueous environment. The ability to be used in water, its
long diffraction-free distance, and its tolerance to multiple obstacles make
this DF-BSW ideal for certain applications in areas such as the biological
sciences, where many measurements are made on glass surfaces or for which an
aqueous environment is required, and for high-speed interconnections between
chips, where low loss is necessary. Specifically, the DF-BSW on the dielectric
multilayer can be used to develop novel flow cytometry that is based on the
surface wave, but not the free space beam, to detect the surface-bound targets
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