Signal Improvement for Underwater LIBS

We employed a collinear long-short double-pulse laser induced breakdown spectroscopy (LS-DP-LIBS) to detect the underwater metal samples. The emission spectra, time-resolved signal, plasma images and sound characteristics of plasma shockwaves are experimentally investigated in this work. The results show that the underwater signal of Al, Cu and Fe spectral lines are significantly improved by collinear LS-DP-LIBS with inter-pulse delay of 35 us. The mechanism of the signal improvement is considered to be the pre irradiation effect of the long pulse laser beam. In the collinear LS-DP-LIBS method, the long pulse first generates a cavitation bubble in water and provides a gaseous environment. Then the short pulse generates the plasma from the sample surface. The present experiments show that the collinear LS-DP-LIBS method offers a significant signal improvement in underwater measurement of metal samples. This new method has great potential in deep-sea exploration using LIBS

Research on External Influence Factors of Brand Extension into New Markets Based on Ecological Niche Theory

In the economic era of brand, product homogeneity continues to increase market competition and expanding into new markets has become one of the inevitable choice for branding enterprises to obtain sustainable competitive advantage and excess brand profits. This paper is based on ecological niche theory and tries to analyze the external factors of brand expansion into new markets from three aspects: the climatic factor, the soil factor and the topographic factor of the brand. It also analyzes various refined factors one by one and provides the basis for enterprises’ decision making on to new market expansion

Study on the Investors’ Participation Motivations in Award-Based Crowdfunding

Crowdfunding, as a new financing model, has drawn more and more attention in the rapid development of Internet financing. This paper will select the investors in awardbased crowdfunding as the study object, apply grounded theory to explore their participation motivations in the crowdfunding, including 4 major categories: internal motivation, external motivation, internalized external motivation and behavior and 17 sub-categories, further discuss the relationship between the motivations and build a model for analysis

More Insight on Deep Learning-aided Cryptanalysis

In CRYPTO 2019, Gohr showed that well-trained neural networks could perform cryptanalytic distinguishing tasks superior to differential distribution table (DDT)-based distinguishers. This suggests that the differential-neural distinguisher (ND) may use additional information besides pure ciphertext differences. However, the explicit knowledge beyond differential distribution is still unclear. In this work, we provide explicit rules that can be used alongside DDTs to enhance the effectiveness of distinguishers compared to pure DDT-based distinguishers. These rules are based on strong correlations between bit values in right pairs of XOR-differential propagation through addition modulo $2^n$. Interestingly, they can be closely linked to the earlier study of the multi-bit constraints and the recent study of the fixed-key differential probability. In contrast, combining these rules does not improve the NDs\u27 performance. This suggests that these rules or their equivalent form have already been exploited by NDs, highlighting the power of neural networks in cryptanalysis. In addition, we find that to enhance the differential-neural distinguisher\u27s accuracy and the number of rounds, regulating the differential propagation is imperative. Introducing differences into the keys is typically believed to help eliminate differences in encryption states, resulting in stronger differential propagations. However, differential-neural attacks differ from traditional ones as they don\u27t specify output differences or follow a single differential trail. This questions the usefulness of introducing differences in a key in differential-neural attacks and the resistance of Speck against such attacks in the related-key setting. This work shows that the power of differential-neural cryptanalysis in the related-key setting can exceed that in the single-key setting by successfully conducting a 14-round key recovery attack on Speck32/64

SIRT6 Suppresses NFATc4 Expression and Activation in Cardiomyocyte Hypertrophy

NFATc4, a member from the Nuclear Factor of Activated T cells (NFATs) transcription factor family, plays a pivotal role in the development of cardiac hypertrophy. NFATc4 is dephosphorylated by calcineurin and translocated from the cytoplasm to the nucleus to regulate the expression of hypertrophic genes, like brain natriuretic polypeptide (BNP). The present study identified SIRT6, an important subtype of NAD+ dependent class III histone deacetylase, to be a negative regulator of NFATc4 in cardiomyocyte hypertrophy. In phenylephrine (PE)-induced hypertrophic cardiomyocyte model, overexpression of SIRT6 by adenovirus infection or by plasmid transfection repressed the protein and mRNA expressions of NFATc4, elevated its phosphorylation level, prevented its nuclear accumulation, subsequently suppressed its transcriptional activity and downregulated its target gene BNP. By contrast, mutant of SIRT6 without deacetylase activity (H133Y) did not demonstrate these effects, suggesting that the inhibitory effect of SIRT6 on NFATc4 was dependent on its deacetylase activity. Moreover, the effect of SIRT6 overexpression on repressing BNP expression was reversed by NFATc4 replenishment, whereas the effect of SIRT6 deficiency on upregulating BNP was recovered by NFATc4 silencing. Mechanistically, interactions between SIRT6 and NFATc4 might possibly facilitate the deacetylation of NFATc4 by SIRT6, thereby preventing the activation of NFATc4. In conclusion, the present study reveals that SIRT6 suppresses the expression and activation of NFATc4. These findings provide more evidences of the anti-hypertrophic effect of SIRT6 and suggest SIRT6 as a potential therapeutic target for cardiac hypertrophy

Two-dimensional temperature measurement in a high temperature and high pressure combustor using CT-TDLAS with a wide scanning laser at 1335-1375nm

Tunable diode laser absorption spectroscopy (TDLAS) technology is a developing method for temperature and species concentration measurements with the features of non-contact, high precision, high sensitivity, etc. The difficulty of two-dimensional (2D) temperature measurement in actual combustors has not yet been solved because of pressure broadening of absorption spectra, optical accessibility, etc. In this study, the combination of computed tomography (CT) and TDLAS with a wide scanning laser at 1335-1375nm has been applied to a combustor for 2D temperature measurement in high temperature of 300-2000K and high pressure of 0.1-2.5MPa condition. An external cavity type laser diode with wide wavelength range scanning at 1335-1375nm was used to evaluate the broadened H2O absorption spectra due to the high temperature and high pressure effect. The spectroscopic database in high temperature of 300-2000K and high pressure of 0.1-5.0MPa condition has been revised to improve the accuracy for temperature quantitative analysis. CT reconstruction accuracy was also evaluated in different cases, which presented the consistent temperature distribution between CT reconstruction and assumed distributions. The spatial and temporal distributions of temperature in the high temperature and high pressure combustor were measured successfully by CT-TDLAS using the revised spectroscopic database

Investigation of Cerium-Lithium Sealing Treatment of Cobalt-based Conversion Coatings Formed on Aluminum Alloys

A study was conducted to examine methods of adjusting cerium-lithium sealing process parameters in order to improve the corrosion protection capabilities of a cobalt-based chemical conversion film. In order to seal the pores of the cobalt-based conversion coatings, samples were treated in a cerium-lithium deposition bath in optimal process conditions. The optimal treatment condition was determined by examination of finished samples using the scanning electron microscope (SEM) and electrochemical test measurements. The corrosion behaviors of the sealing coatings were studied using an open circuit potential-time monitoring technique (OCPT), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization tests in 3.5 wt.% NaCl solution. It was found that the best treatment process for the cobalt-based conversion coating was sealed in the cerium-lithium sealing solution for 2 h at 90 ℃. DOI: http://dx.doi.org/10.5755/j01.ms.24.4.19132</p

Peptidome workflow of serum and urine samples for biomarker discovery

Peptidomics plays an important role in clinical proteomics and disease-associated biomarker discovery. It has exhibited mounting potential in early noninvasive diagnosis, prognosis, and treatment evaluation of diseases. This article presents an introduction of peptidomics, the entire peptidomic workflows for serum and urine samples, and a brief overview of recent works in this area. The review is designed to enable researchers to find the most suited strategy for their peptidome studies.Natural Science Foundation of China; Fujian Province Department of Science Technolog

Investigating the relationship between hepatitis B virus infection and postpartum depression in Chinese women: a retrospective cohort study

BackgroundPostpartum depression (PPD) is associated with several psychological and obstetric factors. Hepatitis B virus (HBV) infection has been linked with a high risk of depression, but little is known about the relationship between maternal HBV infection and PPD. We aimed to investigate the association between HBV infection and PPD.MethodsThis retrospective cohort study included 3,808 mothers who gave birth in a hospital in southern China. Self-reported Edinburgh Postnatal Depression Scale (EPDS) was used to assess PPD. Multivariate logistic regression was used to determine whether maternal HBV infection was associated with PPD risk.ResultsOf the 3,808 participants, 11.9% of mothers had PPD at 6 weeks postpartum. Two hundred and seventy-eight (7.3%) and 3,530 (92.7%) were in the HBV and control groups, respectively. Women with HBV infection were more likely to test positive for PPD (14.7 vs.11.7%). The multivariate logistic regression analysis showed that HBV-infected women did not have a significantly higher incidence of PPD (OR = 1.23; 95% CI, 0.82–1.84) than those without HBV infection in the study cohort. Parity and postpartum hemorrhage were found to be associated with PPD. In addition, our study showed that e antigen positivity was not associated with PPD risk (OR = 0.56, 95% CI 0.19–1.63).ConclusionsTo our knowledge, this is the first investigation of the relationship between maternal HBV infection and PPD. In a cohort of women without prior history or family history of mental illness, having HBV infection was not significantly associated with self-reporting of PPD compared to not having HBV infection