Enhancing Representation Learning for Periodic Time Series with Floss: A Frequency Domain Regularization Approach

Time series analysis is a fundamental task in various application domains, and deep learning approaches have demonstrated remarkable performance in this area. However, many real-world time series data exhibit significant periodic or quasi-periodic dynamics that are often not adequately captured by existing deep learning-based solutions. This results in an incomplete representation of the underlying dynamic behaviors of interest. To address this gap, we propose an unsupervised method called Floss that automatically regularizes learned representations in the frequency domain. The Floss method first automatically detects major periodicities from the time series. It then employs periodic shift and spectral density similarity measures to learn meaningful representations with periodic consistency. In addition, Floss can be easily incorporated into both supervised, semi-supervised, and unsupervised learning frameworks. We conduct extensive experiments on common time series classification, forecasting, and anomaly detection tasks to demonstrate the effectiveness of Floss. We incorporate Floss into several representative deep learning solutions to justify our design choices and demonstrate that it is capable of automatically discovering periodic dynamics and improving state-of-the-art deep learning models.Comment: 12 page

Determination of protein–DNA binding constants and specificities from statistical analyses of single molecules: MutS–DNA interactions

Atomic force microscopy (AFM) is a powerful technique for examining the conformations of protein–DNA complexes and determining the stoichiometries and affinities of protein–protein complexes. We extend the capabilities of AFM to the determination of protein–DNA binding constants and specificities. The distribution of positions of the protein on the DNA fragments provides a direct measure of specificity and requires no knowledge of the absolute binding constants. The fractional occupancies of the protein at a given position in conjunction with the protein and DNA concentrations permit the determination of the absolute binding constants. We present the theoretical basis for this analysis and demonstrate its utility by characterizing the interaction of MutS with DNA fragments containing either no mismatch or a single mismatch. We show that MutS has significantly higher specificities for mismatches than was previously suggested from bulk studies and that the apparent low specificities are the result of high affinity binding to DNA ends. These results resolve the puzzle of the apparent low binding specificity of MutS with the expected high repair specificities. In conclusion, from a single set of AFM experiments, it is possible to determine the binding affinity, specificity and stoichiometry, as well as the conformational properties of the protein–DNA complexes

Characterization of a Ag+-Selective Electrode Based on Naphthalimide Derivative as Ionophore

A naphthalimide derivative has been explored as neutral ionophore for Ag+-selective electrode. Potentiometric response revealed that electrode based on the proposed ionophore with 2-nitrophenyl octyl ether as solvent in a poly (vinyl chloride) membrane matrix shows a measuring range of 1.0×10-6-1.0×10-2 M with a slope of 50.4±0.3 mV/decade. This electrode has high selectivity to Ag+ with respect to alkaline, alkaline earth and other heavy metal ions

Polarization-encrypted high-resolution full-color images exploiting hydrogenated amorphous silicon nanogratings

As a prominent alternative to toxic dyes/pigments, nanostructural color pixels have garnered tremendous attention in applications related to display/imaging devices and color printings. However, current color pixels mostly offer static color responses. In relation to this, dynamic color tuning properties must be investigated in order to expand their functionalities and promote their use in the fields of encryption and anti-counterfeiting. In this study, a simple array of hydrogenated amorphous silicon nanogratings is proposed to realize polarization-encrypted full-color images via the coupling of incident light into different leaky mode resonances within the nanogratings. The proposed pixels can readily switch from vivid full colors to indistinguishable orange color by altering the incident polarization state. Hence, unlike the reported polarization-tuned color generation schemes that merely allow for the color variation of the image or require complicated designs to hide the color information, the proposed approach can encrypt arbitrary full-color images via a simple tuning of the incident polarization state. Owing to the localized leaky mode resonances supported by the nanogratings, the pixel can still implement the polarization-encrypted functionality even when it contains only four gratings, thus enabling a remarkably high resolution. The proposed simple scheme may provide a credible new pathway for accelerating the practical applications of high-resolution encryption and anti-counterfeitingThis work was supported by the National Natural Science Foundation of China (NSFC) (Grant Nos. 61805101 and 61604060), the Natural Science Foundation of Shandong Province (Grant Nos. ZR2019BF013, ZR2017JL027, ZR2018BF025, Funder Id: http://dx.doi.org/10.13039/501100007129), and by the China Postdoctoral Science Foundation (Grant No. 2018M632605). This work was performed in part at the ACT node of the Australian National Fabrication Facility, a company established under the National Collaborative Research Infrastructure Strategy to provide nano and micro-fabrication facilities for Australia’s researchers

The efficacy and safety of Niaoduqing granules in the treatment of diabetic kidney disease: a systematic review and meta-analysis

Background: Diabetic nephropathy (DN) is the main cause of chronic kidney disease (CKD) and end-stage renal failure (ESRF), and the control of disease progression and adverse events during treatment needs to be improved.Objective: This study aimed to systematically evaluate the clinical efficacy and safety of Niaoduqing granules (NDQG) in the treatment of diabetic kidney disease (DKD).Method: Randomized controlled trials (RCTs) of NDQG for DKD from Chinese and English databases up to 31 August 2022 were included. The quality of the literature was assessed using the risk of bias tool of the Cochrane Handbook. At a 95% confidence interval (CI), relative risk (RR) and Cohen’s d were used for the categorical and continuous variables, respectively, and Stata 16.0 software was used for statistical analysis. A funnel plot and Egger’s tests were used to assess publication bias.Result: A total of 4,006 patients were included in 52 RCTs, including 1,987 cases in the control group and 2,019 cases in the treatment group. Compared with conventional treatment (CT), combined NDQG therapy is more effective in improving clinical efficiency [RR = 1.23, 95% confidence interval (1.17, 1.29), p < 0.001, I2 = 53.17%], kidney function (urinary albumin excretion rate [SMD = −0.90, 95% CI (−1.14, −0.66), p < 0.001, I2 = 78.19%], 24hUTP levels [SMD = −0.81, 95% CI (−1.08, −0.55), p < 0.001, I2 = 87.08%], blood urea nitrogen [SMD = −0.54, 95% CI (−0.69, −0.39), p < 0.01, I2 = 77.01%], SCr [SMD = −0.68, 95% CI (−0.90, −0.45), p < 0.001, I2 = 89.97%], CCr [SMD = 0.76, 95% CI (0.10,1.42), p = 0.02, I2 = 95.97%], and Cys-C [SMD = −1.32, 95% CI (−2.25, −0.40), p = 0.01, I2 = 93.44%]), the level of glucose metabolism (fasting blood glucose [SMD = −0.18, 95% CI (−0.38, 0.03), p = 0.10, I2 = 71.18%] and HbA1c [SMD = −0.42, 95% CI (−0.86, −0.02), p = 0.06, I2 = 81.64%]), the level of lipid metabolism (total cholesterol [SMD = −0.70, 95% CI (−1.01, −0.39), p < 0.001, I2 = 86.74%] and triglyceride [SMD = −0.61, 95% CI (−0.87,−0.36), p < 0.001, I2 = 80.64%]), inflammatory factors (Hs-CRP [SMD = −1.00, 95% CI (−1.54, −0.46), p < 0.001, I2 = 86.81%], IL-18 [SMD = −1.25, 95% CI (−1.58, −0.92), p < 0.001, I2 = 0], and TNF-α [SMD = −1.28, 95% CI (−1.64, −0.91), p < 0.001, I2 = 75.73%]), and indicators of oxidative stress (malondialdehyde [SMD = −0.88, 95% CI (−1.22, −0.54), p < 0.001, I2 = 66.01%] and advanced oxidation protein products [SMD = −0.92, 95% CI (−1.85, 0.00), p < 0.001, I2 = 90.68%]). In terms of improving uric acid [SMD = −1.59, 95% CI (−3.45, 0.27), p = 0.09, I2 = 94.67%], 2hPG [SMD = −0.04, 95% CI (−0.61, 0.53), p = 0.89, I2 = 84.33%], HDL-C [SMD = 0.71, 95% CI (0.02, 1.40), p = 0.04, I2 = 87.43%], Hb [SMD = 0.11, 95% CI (−0.10, 0.32), p = 0.32, I2 = 0.00]), and superoxide dismutase [SMD = 1.32, 95% CI (0.44, 2.20), p < 0.001, I2 = 93.48%], the effect is not obvious. Adjuvant treatment with NDQG did not increase the incidence of adverse reactions in the control group [SMD = 0.98, 95% CI (0.71, 1.34), p = 0.89, I2 = 1.59%]. Obvious publication bias was detected by funnel plot and Egger’s test.Conclusion: Our meta-analysis showed that adjuvant treatment with NDQG has more advantages than conventional treatment alone in the DKD treatment, which could improve clinical efficiency, kidney function, the level of glucose metabolism, the level of lipid metabolism, inflammatory factors, and oxidative stress indicators. At the same time, it also showed that NDQG are relatively safe. However, more high-quality studies are needed to provide more reliable evidence for clinical use.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022373726, identifier CRD42022373726

Protective Role of Nuclear Factor E2-Related Factor 2 against Acute Oxidative Stress-Induced Pancreatic β

Oxidative stress is implicated in the pathogenesis of pancreatic β-cell dysfunction that occurs in both type 1 and type 2 diabetes. Nuclear factor E2-related factor 2 (NRF2) is a master regulator in the cellular adaptive response to oxidative stress. The present study found that MIN6 β-cells with stable knockdown of Nrf2 (Nrf2-KD) and islets isolated from Nrf2-knockout mice expressed substantially reduced levels of antioxidant enzymes in response to a variety of stressors. In scramble MIN6 cells or wild-type islets, acute exposure to oxidative stressors, including hydrogen peroxide (H2O2) and S-nitroso-N-acetylpenicillamine, resulted in cell damage as determined by decrease in cell viability, reduced ATP content, morphology changes of islets, and/or alterations of apoptotic biomarkers in a concentration- and/or time-dependent manner. In contrast, silencing of Nrf2 sensitized MIN6 cells or islets to the damage. In addition, pretreatment of MIN6 β-cells with NRF2 activators, including CDDO-Im, dimethyl fumarate (DMF), and tert-butylhydroquinone (tBHQ), protected the cells from high levels of H2O2-induced cell damage. Given that reactive oxygen species (ROS) are involved in regulating glucose-stimulated insulin secretion (GSIS) and persistent activation of NRF2 blunts glucose-triggered ROS signaling and GSIS, the present study highlights the distinct roles that NRF2 may play in pancreatic β-cell dysfunction that occurs in different stages of diabetes