Conexiones políticas y comprensibilidad de los estados financieros: Datos de China

High-quality information disclosure improves the accuracy of investors’ judgment and efficiency in resource allocation. With a focus on the readability of information disclosed, this study analyzes how political connections affect the readability of financial statements by taking A-share private-owned companies listed onShanghai and Shenzhen Stock Exchanges as research sample from 2008 to 2019. We use ordinary leastsquares model and moderating effect model as our main methodology. A series of robustness tests are alsocarried out. Our research finds that companies with political connections are more likely to issue less read-able financial statements. This negative impact is diminished for the firms with a higher marketization level,better corporate governance, and greater analyst coverage. Further research on the economic consequences demonstrates that political connections would weaken the positive effect of the readability of financial state-ments on the firm’s future market value. This study enriches the research on the factors influencing the readability of financial statements and reveals the economic consequences of political connections in termsof textual information disclosure quality. It is therefore an important reference for regulatory authoritiesto formulate guidelines on text information disclosure and supervise the compliance of politically affiliated enterprises, while facilitating listed companies to enhance the readability of their financial statementsLa divulgación de información de alta calidad mejora la precisión del juicio de los inversores y la eficiencia en la asignación de recursos. Centrándose en la comprensibilidad de la información divulgada, este estudio analiza cómo las conexiones políticas afectan a la comprensibilidad de los estados financieros tomando como muestra de investigación las empresas privadas de acciones A cotizadas en las bolsas de Shangháiy Shenzhen entre 2008 y 2019. Utilizamos el modelo de mínimos cuadrados ordinarios y el modelo de efecto moderador como metodología principal. También se llevan a cabo una serie de pruebas de robustez. Nuestra investigación encuentra que las empresas con conexiones políticas son más propensas a emitir estados financieros menos comprensibles. Este efecto negativo disminuye en las empresas con mayor nivel de comercialización, mejor gobierno corporativo y mayor cobertura de los analistas. Otras investigaciones sobre las consecuencias económicas demuestran que las conexiones políticas debilitarían el efecto positivo de la comprensibilidad de los estados financieros sobre el futuro valor de mercado de la empresa. Este estudio enriquece la investigación sobre los factores que influyen en la legibilidad de los estados financieros y revela las consecuencias económicas de las conexiones políticas en términos de calidad de la divulgación de información textual. Por lo tanto, constituye una referencia importante para que las autoridades reguladoras formulen directrices sobre la divulgación de información textual y supervisen el cumplimiento de las empresas con conexiones políticas, al tiempo que facilita a las empresas cotizadas en bolsa la mejora de la legibilidad de sus estados financieros

Improvement of two-way continuous-variable quantum key distribution using optical amplifiers

The imperfections of a receiver's detector affect the performance of two-way continuous-variable quantum key distribution protocols and are difficult to adjust in practical situations. We propose a method to improve the performance of two-way continuous-variable quantum key distribution by adding a parameter-adjustable optical amplifier at the receiver. A security analysis is derived against a two-mode collective entangling cloner attack. Our simulations show that the proposed method can improve the performance of protocols as long as the inherent noise of the amplifier is lower than a critical value, defined as the tolerable amplifier noise. Furthermore, the optimal performance can approach the scenario where a perfect detector is used.Comment: 14 pages, 7 figure

A full-reference image quality assessment for multiply distorted image based on visual mutual information

A full-reference image quality assessment (FR-IQA) method for multi-distortion based on visual mutual information (MD-IQA) is proposed to solve the problem that the existing FR-IQA methods are mostly applicable to single-distorted images, but the assessment result for multiply distorted images is not ideal. First, the reference image and the distorted image are preprocessed by steerable pyramid decomposition and contrast sensitivity function (CSF). Next, a Gaussian scale mixture (GSM) model and an image distorted model are respectively constructed for the reference images and the distorted images. Then, visual distorted models are constructed both for the reference images and the distorted images. Finally, the mutual information between the processed reference image and the distorted image is calculated to obtain the full-reference quality assessment index for multiply distorted images. The experimental results show that the proposed method has higher accuracy and better performance for multiply distorted images

No-reference image quality assessment based on the AdaBoost BP neural network in the wavelet domain

Considering the relatively poor robustness of quality scores for different types of distortion and the lack of mechanism for determining distortion types, a no-reference image quality assessment (NR-IQA) method based on the AdaBoost BP Neural Network in Wavelet domain (WABNN) is proposed. A 36-dimensional image feature vector is constructed by extracting natural scene statistics (NSS) features and local information entropy features of the distorted image wavelet sub-band coefficients in three scales. The ABNN classifier is obtained by learning the relationship between image features and distortion types. The ABNN scorer is obtained by learning the relationship between image features and image quality scores. A series of contrast experiments are carried out in the LIVE database and TID2013 database. Experimental results show the high accuracy of the distinguishing distortion type, the high consistency with subjective scores and the high robustness of the method for distorted images. Experiment results also show the independence for the database and the relatively high operation efficiency of this method

Endoscopic rhizotomy for chronic lumbar zygapophysial joint pain.

BACKGROUND: Chronic lumbar zygapophysial joint pain is a common cause of chronic low back pain. Percutaneous radiofrequency ablation (RFA) is one of the effective management options; however, the results from the traditional RFA need to be improved in certain cases. The aim of this study is to investigate the effect of percutaneous radiofrequency ablation under endoscopic guidance (ERFA) for chronic low back pain secondary to facet joint arthritis. METHODS: This is a prospective study enrolled 60 patients. The cases were randomized into two groups: 30 patients in the control group underwent traditional percutaneous radiofrequency ablation, others underwent ERFA. The lumbar visual analog scale (VAS), MacNab score, and postoperative complications were used to evaluate the outcomes. All outcome assessments were performed at postoperative 1 day, 1 month, 3 months, 6 months, and 12 months. RESULTS: There was no difference between the two groups in preoperative VAS (P \u3e 0.05). VAS scores, except the postoperative first day, in all other postoperative time points were significantly lower than preoperative values each in both groups (P \u3c 0.05). There was no significant difference between the two groups in VAS at 1 day, 1 month, and 3 months after surgery (P \u3e 0.05). However, the EFRA demonstrated significant benefits at the time points of 3 months and 6 months (P \u3e 0.05). The MacNab scores of 1-year follow-up in the ERFA group were higher than that in the control group (P \u3c 0.05). The incidence of complications in the ERFA group was significantly less than that in the control group (P \u3c 0.05). CONCLUSIONS: ERFA may achieve more accurate and definite denervation on the nerves, which leads to longer lasting pain relief

Clinical study of Bian-shi therapy to mitigate insomnia symptoms in young and middle-aged patients with chronic insomnia by regulating neurotransmitters

Objective To investigate the therapeutic mechanism of Bian-shi therapy in improving sleep quality in young and middle-aged patients with chronic insomnia. Methods 40 young and middle-aged patients with chronic insomnia were randomly divided into the western medicine group （n = 20） and Bian-shi group （n = 20）. In the western medicine group， patients were orally treated with zopiclone （7.5 mg， oral administration before bedtime）， and those in the Bian-shi group were treated with placebo and Bian-shi therapy （once a week， 40 min a time， 4 times in total）. The changes of Pittsburgh Sleep Quality Index （PSQI）， and serum melatonin， acetylcholine and norepinephrine before and after 30 d treatment were analyzed and compared between two groups. Results After 30 d treatment， PSQI scores were significantly lower compared with those before treatment in two groups （both P < 0.05）. In the Bian-shi group， PSQI scores were more significantly decreased than those in the western medicine group （all P < 0.05）. After 30 d treatment， serum levels of melatonin and acetylcholine were significantly higher， whereas norepinephrine levels were significantly lower than those before treatment in two groups （all P < 0.05）. In the Bian-shi group， serum levels of melatonin and acetylcholine were significantly higher， whereas norepinephrine levels were significantly lower compared with those in the western medicine group （all P < 0.05）. Conclusions Bian-shi therapy can effectively improve the sleep quality of young and middle-aged patients with chronic insomnia， which yields higher clinical efficacy than that of zopiclone tablets. Multiple neurotransmitters may be involved in the mechanism of Bian-shi therapy to mitigate chronic insomnia symptoms