Offset quantum-well method for tunable distributed Bragg reflector lasers and electro-absorption modulated distributed feedback lasers

A two-section offset quantum-well structure tunable laser with a tuning range of 7 nm was fabricated using offset quantum-well method. The distributed Bragg reflector (DBR) was realized just by selectively wet etching the multiquantum-well (MQW) layer above the quaternary lower waveguide. A threshold current of 32 mA and an output power of 9 mW at 100 mA were achieved. Furthermore, with this offset structure method, a distributed feedback (DFB) laser was integrated with an electro-absorption modulator (EAM), which was capable of producing 20 dB of optical extinction

Positive correlation between fatty liver index and hyperuricemia in hypertensive Chinese adults: a H-type hypertension registry study

BackgroundFew studies have examined the relationship between fatty liver index (FLI) and hyperuricemia (HUA). This study explores the relationship between FLI and HUA in hypertensive patients.MethodsA total of 13,716 hypertensive subjects were included in the current study. FLI, a simple index calculated from triglycerides (TG), waist circumference (WC), body mass index (BMI), and γ -glutamyltransferase (GGT), was used as a useful predictor of nonalcoholic fatty liver disease (NAFLD) distribution. HUA was defined as serum uric acid ≥ 360 μmol/L for females and ≥ 420 μmol/L for males.ResultsThe mean value of total FLI was 31.8 ± 25.1. Multiple logistic analyses revealed a significant positive correlation between FLI and HUA (OR, 1.78; 95% CI: 1.69–1.87). A subgroup analysis demonstrated that the correlation between FLI (< 30 vs. ≥ 30) and HUA was significant in both sexes (P for interaction = 0.006). Further analyses stratified by sex indicated a positive correlation between FLI and HUA prevalence among male and female subjects. However, the correlation between FLI and HUA was stronger in female subjects than in males (male: OR, 1.70; 95% CI: 1.58–1.83; female: 1.85; 95% CI: 1.73–1.98).ConclusionThis study demonstrates a positive correlation between FLI and HUA in hypertensive adults, but stronger in females than males

Are You Copying My Model? Protecting the Copyright of Large Language Models for EaaS via Backdoor Watermark

Large language models (LLMs) have demonstrated powerful capabilities in both text understanding and generation. Companies have begun to offer Embedding as a Service (EaaS) based on these LLMs, which can benefit various natural language processing (NLP) tasks for customers. However, previous studies have shown that EaaS is vulnerable to model extraction attacks, which can cause significant losses for the owners of LLMs, as training these models is extremely expensive. To protect the copyright of LLMs for EaaS, we propose an Embedding Watermark method called EmbMarker that implants backdoors on embeddings. Our method selects a group of moderate-frequency words from a general text corpus to form a trigger set, then selects a target embedding as the watermark, and inserts it into the embeddings of texts containing trigger words as the backdoor. The weight of insertion is proportional to the number of trigger words included in the text. This allows the watermark backdoor to be effectively transferred to EaaS-stealer's model for copyright verification while minimizing the adverse impact on the original embeddings' utility. Our extensive experiments on various datasets show that our method can effectively protect the copyright of EaaS models without compromising service quality.Comment: Accepted by ACL 202

The impact of risk perception and information acquisition on meteorological adaptive behavior of large grain farmers

Based on the survey data of 414 large grain farmers in 11 counties and cities in Poyang Lake District of Jiangxi Province, this paper used structural equation modelling (SEM) and hierarchical regression method to explore the relationship between risk perception, information acquisition, human capital and meteorological disaster adaptive behaviour of large grain farmers. This paper focuses on the mediating role of information acquisition in risk perception and adaptive behaviour and the moderating role of human capital in information acquisition and adaptive behaviour. The results show that the risk perception of large grain farmers has a significant positive effect on their information acquisition and adaptive behaviour. Information acquisitionability of large grain farmers has a significant positive effect on their adaptive behaviour, and there exists a mediating effect between risk perception and adaptive behaviour; the human capital of large grain farmers does not play a moderating role in the impact of risk perception on information acquisition, yet has a significant positive moderating effect on the impact of information acquisition on adaptive behaviour. The results reveal the mechanism of meteorological disaster adaptive behaviour of large grain farmers and its influencing factors, which can be used as a reference for the government to make relevant policies

The impact of risk perception and information acquisition on meteorological adaptive behavior of large grain farmers

Based on the survey data of 414 large grain farmers in 11 counties and cities in Poyang Lake District of Jiangxi Province, this paper used structural equation modelling (SEM) and hierarchical regression method to explore the relationship between risk perception, information acquisition, human capital and meteorological disaster adaptive behaviour of large grain farmers. This paper focuses on the mediating role of information acquisition in risk perception and adaptive behaviour and the moderating role of human capital in information acquisition and adaptive behaviour. The results show that the risk perception of large grain farmers has a significant positive effect on their information acquisition and adaptive behaviour. Information acquisitionability of large grain farmers has a significant positive effect on their adaptive behaviour, and there exists a mediating effect between risk perception and adaptive behaviour; the human capital of large grain farmers does not play a moderating role in the impact of risk perception on information acquisition, yet has a significant positive moderating effect on the impact of information acquisition on adaptive behaviour. The results reveal the mechanism of meteorological disaster adaptive behaviour of large grain farmers and its influencing factors, which can be used as a reference for the government to make relevant policies

Low-Microwave Loss Coplanar Waveguides Fabricated on High-Resistivity Silicon Substrate

Three kinds of coplanar waveguides （CPWs） are designed and fabricated on different silicon substrates---common low-resistivity silicon substrate （LRS）, LRS with a 3μm-thick silicon oxide interlayer, and high-resistivity silicon （HRS） substrate. The results show that the microwave loss of a CPW on LRS is too high to be used, but it can be greatly reduced by adding a thick interlayer of silicon oxide between the CPW transmission lines and the LRS.A CPW directly on HRS shows a loss lower than 2dB/cm in the range of 0-26GHz and the process is simple,so HRS is a more suitable CPW substrate

Integrated electroabsorption-modulated DFB laser by using an improved butt-joint method

An improved butt coupling method is used to fabricate an electroabsorption modulator (EAM) monolithically integrated with a distributed feedback (DFB) laser. The obtained electroabsorption-modulated laser (EML) chip with the traditional shallow ridge exhibits very low threshold current of 12 mA, output power of more than 8 mW, and static extinction ratio of -7 dB at the applied bias voltage from 0.5 to -2.0 V