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This paper investigates the adaptive tracking control problem of a class of nonlinear systems with intermittent actuator faults and prescribed performance. In the backstepping design process, a performance function is incorporated to ensure that the tracking error adheres to the prescribed performance criteria. Simultaneously, multi‐dimensional Taylor networks are used to approximate the unknown nonlinear functions in the system. Subsequently, to avoid jumps in the improved Lyapunov function when faults occur, a boundary estimation method is presented, which effectively compensates for the impact of intermittent actuator faults. Ultimately, based on Lyapunov stability theory, it is proven that all signals of the closed‐loop system are bounded, and the tracking error can satisfy the prescribed transient and steady‐state performance. Simulation results demonstrate the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

Summary: In this paper, an event‐triggered adaptive tracking control strategy is proposed for strict‐feedback stochastic nonlinear systems with predetermined finite‐time performance. Firstly, a finite‐time performance function (FTPF) is introduced to describe the predetermined tracking performance. With the help of the error transformation technique, the original constrained tracking error is transformed into an equivalent unconstrained variable. Then, the unknown nonlinear functions are approximated by using the multi‐dimensional Taylor networks (MTNs) in the backstepping design process. Meanwhile, an event‐triggered mechanism with a relative threshold is introduced to reduce the communication burden between actuators and controllers. Furthermore, the proposed control strategy can ensure that all signals of the closed‐loop system are bounded in probability and the tracking error is within a predefined range in a finite time. In the end, the effectiveness of the proposed control strategy is verified by two simulation examples. [ABSTRACT FROM AUTHOR]

Background: The performance of lung cancer screening with low‐dose computed tomography (CT) (LDCT) in China is uncertain. This study aimed to evaluate the performance of LDCT lung cancer screening in the Chinese setting. Methods: In 2014, a screening cohort of lung cancer with LDCT was established in Gejiu, Yunnan Province, a screening center of the Lung Cancer Screening Program in Rural China (LungSPRC). Participants received a baseline screening and four rounds of annual screening with LDCT in two local hospitals until June 2019. We analyzed the rates of participation, detection, early detection, and the clinical characteristics of lung cancer. Results: A total of 2006 participants had complete baseline screening results with a compliance rate of 98.4%. Of these, 1411 were high‐risk and 558 were nonhigh‐risk participants. During this period, 40 lung cancer cases were confirmed, of these, 35 were screen‐detected, four were post‐screening and one was an interval case. The positive rate of baseline and annual screening was 9.7% and 9.0%, while the lung cancer detection rate was 0.4% and 0.6%, respectively. The proportion of early lung cancer increased from 37.5% in T0 to 75.0% in T4. Adenocarcinoma was the most common histological subtype. Lung cancer incidence according to the criteria of LungSPRC and National Lung Cancer Screening Trial (NLST) was 513.31 and 877.41 per 100 000 person‐years, respectively. Conclusions: The program of lung cancer screening with LDCT showed a successful performance in Gejiu, Yunnan. However, further studies are warranted to refine a high‐risk population who will benefit most from LDCT screening and reduce the high false positive results. Key points: This study reports the results of lung cancer screening with LDCT in Gejiu, Yunnan, a high‐risk area of lung cancer, and it demonstrates that lung cancer screening with LDCT is effective in detecting early‐stage lung cancer. Our program provides an opportunity to explore the performance of LDCT lung cancer screening in the Chinese context. [ABSTRACT FROM AUTHOR]

Background Lung cancer is the leading cause of cancer-related death in China. Results from a randomized controlled trial using annual low-dose computed tomography ( LDCT) in specific high-risk groups demonstrated a 20% reduction in lung cancer mortality. Methods A China national lung cancer screening guideline was developed by lung cancer early detection and treatment expert group appointed by the National Health and Family Planning Commission, based on results of the National Lung Screening Trial, systematic review of evidence related to LDCT screening, and protocol of lung cancer screening program conducted in rural China. Results Annual lung cancer screening with LDCT is recommended for high risk individuals aged 50-74 years who have at least a 20 pack-year smoking history and who currently smoke or have quit within the past five years. Individualized decision making should be conducted before LDCT screening. LDCT screening also represents an opportunity to educate patients as to the health risks of smoking; thus, education should be integrated into the screening process in order to assist smoking cessation. Conclusions A lung cancer screening guideline is provided for the high-risk population in China. [ABSTRACT FROM AUTHOR]

Most tumor cells show different metabolic pathways than normal cells. Even under the conditions of sufficient oxygen, they produce energy by a high rate of glycolysis followed by lactic acid fermentation in the cytosol, which is known as aerobic glycolysis or the Warburg effect. Lung cancer is a malignant tumor with one of the highest incidence and mortality rates in the world at present. However, the exact mechanisms underlying lung cancer development remain unclear. The three key enzymes of glycolysis are hexokinase, phosphofructokinase, and pyruvate kinase. Lactate dehydrogenase catalyzes the transfer of pyruvate to lactate. All four enzymes have been reported to be overexpressed in tumors, including lung cancer, and can be regulated by many oncoproteins to promote tumor proliferation, migration, and metastasis with dependence or independence of glycolysis. The discovery of aerobic glycolysis in the 1920s has provided new means and potential therapeutic targets for lung cancer. [ABSTRACT FROM AUTHOR]

Angiogenesis is an indispensible process for tumor growth and metastasis. Anti-angiogenesis based therapy is one of the most promising treatments for inhibiting cancer progression. Through the exploration of inhibitors of vascular endothelial growth factor receptor ( VEGFR)-2, deemed as the major angiogenesis pathway, pazopanib was found as a small molecular pan- VEGFR and pan-platelet-derived growth factor receptor (PDGFR) inhibitor, with suitable pharmacodynamic and pharmacokinetic parameters to be an oral drug. In an vitro study, pazopanib exerted anti-tumor effect through mechanisms including the Raf- MAPK/ERK ( MEK)-extracellular signal-regulated kinase (ERK) pathway, and directly targeted on v-raf murine sarcoma viral oncogene homolog B ( B-raf) as well. It inhibited the proliferation of cell lines, such as DU-145 and HRC-45 in hepatocellular carcinoma, through mechanisms like 'cell cycle arrest.' In vivo xenograft studies and phase I/ II clinical trials revealed a series of plasma cytokine and angiogenic factors, such as interleukin ( IL)-6, IL-12, hepatocyte growth factor ( HGF), and soluble VEGFR2, which have significant association with clinical curative effect. Pazopanib has been shown to be effective in solid tumors and some hematological malignancies. Future studies should focus on the exploration of biomarkers to screen sensitive patients and concomitant or metronomic dosage with other kinds of medicines. [ABSTRACT FROM AUTHOR]

Background: Phase II-III trials in patients with untreated and previously treated locally advanced or non-small cell lung cancer ( NSCLC) suggested that Endostar was able to enhance the effect of platinum-based chemotherapy ( NP regimen) with tolerable adverse effects. Methods Four hundred and eighty six patients were randomized into two arms: study arm A: NP plus Endostar (n = 322; vinorelbine, cisplatin, Endostar), and study arm B: NP plus placebo (n = 164; vinorelbine, cisplatin, 0.9% sodium chloride). Patients were treated every third week for two to six cycles. Results: Overall response rates were 35.4% in arm A and 19.5% in arm B (P = 0.0003). The median time to progression was 6.3 months for arm A and 3.6 months for B, respectively (P < 0.001). The clinical benefit rates were 73.3% in arm A and 64.0% in arm B (P = 0.035). Grade 3/4 neutropenia, anemia, and nausea/vomiting were 28.5%, 3.4%, and 8.0%, respectively, in Arm A compared with 28.2%, 3.0%, and 6.6%, respectively, in Arm B (P > 0.05). There were two treatment related deaths in arm A and one in arm B (P > 0.05). The median overall survival was longer in arm A than in arm B (P < 0.0001). Conclusion: Long-term follow-up revealed that the addition of Endostar to an NP regimen can result in a significant clinical and survival benefit in advanced NSCLC patients, compared with NP alone. [ABSTRACT FROM AUTHOR]

The aims of our study were to estimate the contribution of known lung cancer risk factors, and provide evidence to support the National Cancer Prevention and Control Program in China. We calculated the proportion of lung cancer attributable to specific risk factors. Data on exposure prevalence were from meta-analyses and large-scale national surveys of representative samples of the Chinese population. Data on relative risks were from meta-analyses and large-scale prospective studies. Lung cancer mortality and incidence were taken from the Third National Death Survey and from cancer registries in China. We estimated that in China 285 304 lung cancer deaths and 327 465 cases were attributable to smoking, involuntary smoking (women only), occupational exposure, indoor radon, and low fruit intake in 2005. The proportion of lung cancer deaths attributable to smoking, involuntary smoking among non-smoking women, occupational exposure, indoor radon and low fruit intake was 56.9%, 11.1%, 9.5%, 0.2% and 12.4%, respectively. About 41% of lung cancer mortality and incidence in women was caused by risk factors in our study. However, over half of lung cancer deaths and cases among women were not attributable to known risk factors. It is necessary to conduct large-scale studies to identify additional risk factors of lung cancer in non-smoking women. [ABSTRACT FROM AUTHOR]

The prerequisites for a commercial fermentation process of biosurfactants include the use of low- or negative-cost substrates and maximum conversion yields. Under competitive market conditions, the price of canola oil is expected to decrease in response to its increased supply. Lactose, obtained from cheese whey, is a by-product of the dairy industry. In this work, canola oil with glucose or lactose as carbon sources was used as substrates to produce sophorose lipids (SLs) by means of the yeast Candida bombicola. Fermentations were conducted in either shaker flasks or 1-L Bellco (Vineland, NJ) stirred reactors for 5-7 d at 450 rpm and 30°C. The production of SLs reached 150-160 g/L in a medium consisting of 10% glucose, 10.5% canola oil, 0.1% urea and 0.4% yeast extract. When lactose was substituted for glucose, 90-110 g/L SL was obtained. The apolar SL 17- l-([2′- O-β- d-glucopyranosyl-β- d-glucopyransoyl]oxy)-octadecanoic acid 1′-4″-lactone 6′,6″-diacetate (SL-1) was the major one (73%) when canola oil was used instead of safflower oil (SL-1, 50%). Use of canola oil generally resulted in increased yields of SLs comparable to the yields obtained when safflower oil was used in the medium. Other literature reports present yields of 70 g/L and 120 g/L SLs, respectively, with these substrates. [ABSTRACT FROM AUTHOR]