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Bo Li and Na Ma

Integrability Formulas. Part I

In this article, we give several differentiation and integrability formulas of special and composite functions including the trigonometric function, and the polynomial function.

Bo Li and Na Ma

Integrability Formulas. Part III

In this article, we give several differentiation and integrability formulas of composite trigonometric function.

Integrability Formulas. Part II

In this article, we give several differentiation and integrability formulas of special and composite functions including trigonometric function, and polynomial function.


COVID-19 has become a global pandemic and requires the whole world to respond together. There is no specific antiviral treatment recommended at present for COVID-19. The patients must receive the supportive care to help relieve the symptoms and ensure appropriate infection control. Whether or not to use corticosteroids clinically caused controversy. This article has summarized previous researches about the using of corticosteroids in other viral pneumonia, related clinical data in COVID-19, and recommendations in Chinese guideline.


Background: The role of nursing in the management of chest drains is diverse and important. There is a paucity of data regarding the management of chest drains by nurses.

Objective: To establish an evaluation system for nurses to help guide the care of patients being treated with closed thoracic drainage tubes.

Methods: An ADC (availability, dependability, and capacity) model was used as the framework to evaluate treatment guidelines. A questionnaire was developed and tested for reliability and validity based on experimental models of thoracic drainage. Patients were subsequently randomly selected and screened using the effectiveness assessment form.

Results: Overall dimension scores and subgroups were correlated (r > 0.7). Test-retest reliability met required standards (r = 0.769-0.889, p < 0.01). The correlation coefficient between scores of each dimension and total score was 0.542 to 0.920, and correlation coefficients for each item and its dimension were 0.429 to 0.887.

Conclusions: The proposed assessment form provides an evidence-based tool for nurses to effectively manage patients with closed thoracic drainage systems. Experimental and clinical measures confirm the tool’s reliability and validity.


Human immunodeficiency virus (HIV) and tuberculosis (TB) coinfection is a serious public health problem. HIV and TB promote each other, accelerating development of HIV to acquired immunodeficiency syndrome (AIDS) and heightening TB mortality. Determining interaction mechanism between HIV and Mycobacterium tuberculosis can lead to development of effective treatments. This study summarizes prevalence status of AIDS and TB coinfection and research advances concerning their interaction mechanism.


Viral hepatitis C is one of the most prevalent infectious diseases in the world and may cause serious hepatic diseases in the future. Hepatitis C-infected people account for approximately 2% to 3% of the world’s population. The main causes of hepatitis C infection in developing countries are unsafe medical injection and contaminated blood and blood products; whereas in developed countries, it is mainly caused by injection, drug abuse, and high-risk sexual behavior. The focus of hepatitis C prevention and control should be placed on safer blood supply, safer health care and related unnecessary injection, reduction of injection drug use, and high-risk sexual behavior because effective vaccine and postexposure prophylaxis are not yet available.


The aim of this paper is to address the surface reconstruction from point cloud in reverser engineering. The data was acquired through a 3D scan device and was processed as point cloud data. The points in cloud were connected to build 3D surface. The points cloud was processed in four steps to get 3D information surface. First, the subtraction scheme was used to get cover boxes ended with the set of convex was found under the convergence rule. Secondly, the points in the box were projected to the directions which were close to the normal direction method. Thirdly the overlap was avoided by using convergence rule and inner subdivision rule. Finally the information model was used to reconstruction. The method was used in landslide monitoring of Three Gorges area for 3D surface reconstruction and monitoring. The reconstruction method obtains high precision and low complexity. It is effective for large scale monitoring.


In order to properly understand the effect of freezing-thawing circle (FTC) to mechanical behavior of costal soft soil (CSS), unconfined compressive test is conducted. Six kind FTC times are designed from zero to five. The tested data show that: (1) unconfined compressive strength of CCS decreases nonlinearly with more FTC, and the strength after five FTC times becomes about 22% of its original strength without any freezing-thawing experience; (2) stress-strain curves of all unconfined compressive samples can be well fitted by three-parameter hyperbolic model; (3) and relationship between two parameters and FTC times can be fitted by exponent function, while another parameter can be considered as 0.95. Consequently, one composite hyperbolic- exponent empirical formula is established in order to describe freezing-thawing-dependent stress-strain behavior of CSS. Finally, good agreements have been found between tested data and simulated results.


Objective Patients with H1N1 virus infection were hospitalized and quarantined, and some of them developed into acute respiratory failure, and were transfered to the medical intensive care unit of Beijing Ditan Hospital, Capital Medical University in Beijing, China.

Methods The clinical features and preliminary epidemiologic findings among 30 patients with confirmed H1N1 virus infection who developed into acute respiratory failure for ventilatory support were investigated.

Results A total of 30 patients (37.43 ± 18.80 years old) with 2009 influenza A (H1N1) related acute respiratory distress syndrome (ARDS) received treatment with mechanical ventilation, 15 cases of whom were male and 17 cases died of ARDS. Fatal cases were significantly associated with an APACHE Ⅱ score (P = 0.016), but not with PaO2/FIO2 (P = 0.912) and chest radiograph (P = 0.333). The most common complication was acute renal failure (n = 9). Five patients received extracorporeal membrane oxygenation (ECMO), 3 of whom died and the others survived. The major causes of death were multiple organ dysfunction syndrome (MODS) (39%), intractable respiratory failure (27%) and sepsis (20%).

Conclusions Most patients with respiratory failure due to influenza A (H1N1) virus infection were young, with a high mortality, particularly associated with APACHE ∥ score, secondary infection of lung or type 2 diabetes mellitus.