A highly distorted ultraelastic chemically complex Elinvar alloy.

The development of high-performance ultraelastic metals with superb strength, a large elastic strain limit and temperature-insensitive elastic modulus (Elinvar effect) are important for various industrial applications, from actuators and medical devices to high-precision instruments1,2. The elastic strain limit of bulk crystalline metals is usually less than 1 per cent, owing to dislocation easy gliding. Shape memory alloys3-including gum metals4,5 and strain glass alloys6,7-may attain an elastic strain limit up to several per cent, although this is the result of pseudo-elasticity and is accompanied by large energy dissipation3. Recently, chemically complex alloys, such as 'high-entropy' alloys8, have attracted tremendous research interest owing to their promising properties9-15. In this work we report on a chemically complex alloy with a large atomic size misfit usually unaffordable in conventional alloys. The alloy exhibits a high elastic strain limit (approximately 2 per cent) and a very low internal friction (less than 2 × 10-4) at room temperature. More interestingly, this alloy exhibits an extraordinary Elinvar effect, maintaining near-constant elastic modulus between room temperature and 627 degrees Celsius (900 kelvin), which is, to our knowledge, unmatched by the existing alloys hitherto reported.

[Influencing factors of poor treatment adherence in uncontrolled asthma patients in China].

Objective: To evaluate the influencing factors of poor treatment adherence in patients with uncontrolled asthma in China. Methods: From April 2017 to April 2018, all asthma patients with uncontrolled asthma and poor compliance in 32 third-class hospitals in 28 provinces and cities of China mainland included in the "National Mobile Asthma Assessment and Management Project" were selected as the subjects. A total of 923 patients were enrolled in the study including 388 males and 535 females. By analyzing the baseline data of the patients at the initial visit when enrolled, the influencing factors of poor adherence of adult asthma was analyzed by inter-group comparison and χ2 test. Results: Poor compliance in asthma was related to the following factors: age from 59 to 68 years old, course of disease more than 20 years, low education level, non-local follow-up, having obstructive ventilation dysfunction and low awareness of the disease[P values were 0.026(t=1.20), 0.004(t=3.97), 0.001(t=4.92), 0.003(t=3.98), 0.032(t=1.22) and 0.001(t=4.99), respectively]. Totally, 243 patients (26.33%) answered all the questions about asthma correctly. Their medication adherence rating scale (MARS-A) scores were significantly higher than those who answered incompletely correctly (36.23±5.85 vs. 31.77±5.74, P=0.001). Conclusions: The adherence of adult asthma patients was affected by individual and external environment factors. Clinicians should choose individualized methods based on the characteristics of patients. Patient education should be strengthened to improve patients' awareness of the disease at the same time.

[Differential diagnosis of asthma and dysfunctional breathing and vocal cord dysfunction].

The clinical manifestations of bronchial asthma are complex and variable, which can easily be confused with other diseases. So misdiagnosis and missed diagnosis of asthma are common. In the differential diagnosis of asthma, organic diseases such as left ventricular dysfunction, chronic obstructive pulmonary disease, and upper airway obstruction are most often considered, but the understanding of functional disease is insufficient. In fact, GINA guidelines suggested that the differential diagnosis in adult patients with suspected asthma needed to prioritize functional diseases such as dysfunctional breathing (DB)/hyperventilation syndrome (HVS) and vocal cord dysfunction (VCD), rather than organic disease. Here we review the concepts of DB and VCD and their differentiation from asthma.

[An epidemiological survey on clinical features, self-management and cognitive level of elderly asthmatics in China].

Objective: To investigate the prevalence of asthma among the elderly people in China and to analyze the clinical features, self-management and cognitive level of elderly asthma patients. Methods: According to the multi-stage random cluster sampling methods, a total of 164 215 subjects were visited by a questionnaire in the last epidemiology survey from eight provinces (Beijing, Shanghai, Guangdong, Liaoning, Henan, Shanxi, Jiangsu, Sichuan provinces) and seven regions (north, northeast, southern china, east, south, southwest and northwest) in China from February 2010 to August 2012. 2 034 were diagnosed as asthma. The elderly patients aged ≥65 years were selected from the 2 034 asthma patients. The clinical characteristics, comorbidities, the status of asthma control and self-management and insights of the disease in elderly asthma patients were analyzed. Results: Among the 2 034 asthma patients, 584 (28.7%) were elderly asthmatics aged ≥65 years old and 1 450 (71.3%) were<65 years old. In the elderly asthma group, Early-onset asthma accounted for 439 (75.2%) and 145 (24.8%) were late-onset. The common clinical manifestations of elderly asthma patients were: chest distress 395 (67.6%), wheezing 304 (52.1%), cough 298 (51.0%). Common comorbidities of elderly asthmatics were: chronic obstructive pulmonary disease 144 (24.7%), allergic rhinitis 122(20.9%), gastroesopheal reflux disease (GERD) 114(19.5%), allergic conjunctivitis 86 (14.7%), eczema 82 (14.0%), chronic bronchitis 76 (13.0%). The Asthma Control Test (ACT) scores of elderly asthmatics and non-elderly asthmatics were (18.5±3.2) and (21.7±3.4) respectively. There was a significant difference between the two groups (P=0.042). Of the elderly asthmatics, only 13 (2.2%) patients monitored daily using a peak flow meter. 93 (15.9%) patients aware that asthma was characterized by chronic airway inflammation. 64 (11.0%) asthmatics understood that the treatment goal. Conclusions: The clinical manifestations of elderly asthmatics are atypical, especially paroxysmal wheezing. Asthma in elderly people causes more comorbidities and mortality. The self-management and cognitive level of patients with asthma needs to be improved.

[A survey on clinical characteristics and risk factors of severe asthma in China].

Objective: To investigate the clinical characteristics and risk factors of severe bronchial asthma in Chinese people over 14 years old. Methods: According to the multi-stage random cluster sampling methods, a total of 164 215 subjects were visited by a questionnaire in the epidemiology survey from eight provinces (Beijing, Shanghai, Guangdong, Liaoning, Henan, Shanxi, Jiangsu, Sichuan provinces) located in seven regions (north, northeast, east, central China, south, southwest and northwest) of China from February 2010 to August 2012. A total of 2 034 were diagnosed as asthma. The clinical characteristics and related risk factors of patients with severe asthma in China were analyzed. Results: Among all asthma patients, 560 were newly diagnosed, accounting for 27.5% (560/2 034) and the percentage of previously confirmed patients was 72.5% (1 474/2 034). A total of 145 were eligible for severe asthma, accounting for 9.8% (145/1 474) of previously confirmed asthmatics and 7.1% (145/2 034) of all asthmatics. 83.5% (121/145) severe asthmatics had at least one trigger factor. Correlation analysis showed that the risk factors of severe asthma were: smoking (OR=1.543, 95%CI: 1.250-1.814), obesity (OR=2.186, 95%CI: 1.972-2.354), petting (OR=2.135, 95%CI: 1.904-2.283), combined with allergic rhinitis (OR=3.456, 95%CI: 2.721-4.326), gastroesophageal reflux disease (OR=1.842, 95%CI: 1.682-2.140), bronchiectasis (OR=1.665, 95%CI: 1.347-1.912) or chronic obstructive pulmonary disease (OR=1.312, 95%CI: 1.171-1.694). Conclusions: The most common comorbidities in severe asthmatics in China are allergic rhinitis and gastroesophageal reflux disease. The risk factors of severe asthma include obesity, allergic rhinitis, gastroesophageal reflux disease, chronic obstructive pulmonary disease, bronchiectasis, smoking and petting.

Nanoscale Structural Evolution and Anomalous Mechanical Response of Nanoglasses by Cryogenic Thermal Cycling.

One of the central themes in the amorphous materials research is to understand the nanoscale structural responses to mechanical and thermal agitations, the decoding of which is expected to provide new insights into the complex amorphous structural-property relationship. For common metallic glasses, their inherent atomic structural inhomogeneities can be rejuvenated and amplified by cryogenic thermal cycling, thus can be decoded from their responses to mechanical and thermal agitations. Here, we reported an anomalous mechanical response of a new kind of metallic glass (nanoglass) with nanoscale interface structures to cryogenic thermal cycling. As compared to those metallic glasses by liquid quenching, the Sc75Fe25 (at. %) nanoglass exhibits a decrease in the Young's modulus but a significant increase in the yield strength after cryogenic cycling treatments. The abnormal mechanical property change can be attributed to the complex atomic rearrangements at the short- and medium- range orders due to the intrinsic nonuniformity of the nanoglass architecture. The present work gives a new route for designing high-performance metallic glassy materials by manipulating their atomic structures and helps for understanding the complex atomic structure-property relationship in amorphous materials.

[The efficacy and safety of tiotropium/olodaterol fixed-dose combination in Chinese patients with chronic obstructive pulmonary disease: a pooled subgroup analysis of TONADO 1+2].

Objective: To compare the efficacy and safety profiles of tiotropium/olodaterol with the mono-components in Chinese and total study population from TONADO trial. Methods: In the replicate, double-blind, parallel-group, active-controlled, randomized, 52-week, Phase Ⅲ TONADO studies (TONADO 1+2), patients received tiotropium/olodaterol, tiotropium, or olodaterol via the Respimat(®) Inhaler (Boehringer Ingelheim, Germany). Primary end points were forced expiratory volume in 1 second (FEV(1)) area under the curve from 0 to 3 hours (AUC(0-3h)) response and trough FEV(1) response, and St George's respiratory questionnaire (SGRQ) total score at 24 weeks. Adverse events were also collected. This subgroup analysis only focused on the efficacy and safety of the drug at the approved dose in China. Results: 548 Chinese patients were randomized, aged 41 to 82 years [mean age, (63±8) years] and most were male (526, 96%), 111 received tiotropium/olodaterol 5/5 µg, and 127 received tiotropium 5 µg and 95 received olodaterol 5 µg. The baseline characteristics of these groups were similar. After 24 weeks, treatment with tiotropium/olodaterol 5/5 µg, tiotropium 5 µg and olodaterol 5 µg resulted in an adjusted mean FEV(1) AUC(0-3h) response of 0.240, 0.157 and 0.079 L, and trough FEV(1) response of 0.117, 0.068 and-0.001 L, respectively. Tiotropium/olodaterol 5/5 µg significantly improved SGRQ scores in Chinese patients compared with olodaterol 5 µg (32.729 and 37.202, respectively). Generally, the safety profile of tiotropium/olodaterol was comparable with mono-components in 52 weeks. Conclusion: Compared with tiotropium or olodaterol, tiotropium/olodaterol in Chinese patients provided significant improvement in lung function and quality of life, and the safety profiles were similar.

Tuning the indirect-direct band gap transition in the MoS2-xSex armchair nanotube by diameter modulation.

The application of the reported armchair transition-metal dichalcogenide (MoS2, MoTe2, MoSTe and WS2, etc.) nanotube is hindered for the optoelectronic devices due to the indirect band gap. By using first-principles calculations, the electronic structures of MoS2-xSex single-wall armchair nanotubes with respect to different diameters are investigated. The MoS2 armchair nanotube exhibits an indirect band gap as a function of nanotube diameters from 10 Å to 50 Å, whereas MoSSe and MoSe2 exhibit a surprising diameter-induced indirect-direct band gap crossover at the diameters of 25 Å and 33 Å, respectively. We also find that the optical properties of MoS2-xSex armchair nanotubes are anisotropic and strongly depend on the diameter.

[Evaluation of asthma management from the surveys in 30 provinces of China in 2015-2016].

Objective: To evaluate the general level of asthma management in urban areas of China and further promote the national asthma management plan. Methods: A multi-center, cross-sectional survey was carried out in 30 provinces of China (except for Tibet) during Oct 2015 to May 2016. It's a questionnaire-based face-to-face survey which included asthma management using peak flow meter (PFM) and pulmonary function test, medication choice of maintenance therapy and asthma education. Results: A total of 3 875 asthmatic outpatients were recruited including 2 347(60.6%) females and 1 528(39.4%) males. The mean age was (50.7±16.7) years ranging from 14 to 99. Only 10.1%(388/3 837) patients used PFM as monitoring, whereas 62.1%(2 405/3 874) patients underwent pulmonary function test during the past year. There were 57.4%(2 226/3 875) patients treated with inhaled cortical steroid plus long-acting ß(2)-agonist combinations (ICS+LABA) as daily medication. 43.3%(1 661/3 836) patients were followed up by physicians. Among this population, 1 362 asthmatic outpatients were recruited, who also took part in the asthma control survey in 2007-2008 in 10 cities. In this subgroup, 17.9%(244/1 360) were tested by PFM and 66.6%(907/1 362) by pulmonary function test during last year. As to the medication, 63.1%(860/1 362) selected ICS+LABA for daily control. There were 50.4%(685/1 359) patients in the follow-up cohort by physicians. Compared to the similar survey conducted in 2007-2008, the proportion of patients with ICS+LABA regimen and follow-up by physicians were markedly higher, while the rate of PFM use did not have significant improvement. Conclusion: Although the present level of asthma management in China is still far from ideal, asthma management has improved compared to 8 years ago. Yet the use of PFM does not significantly improve. Asthma action plan and application of PFM should be further promoted to improve the level of asthma management.

[Evaluation of asthma disease perception from China national asthma control survey].

Objective: In order to evaluate disease perception of asthma patients in urban China and provide evidence for further specific patient education. Methods: A multi-center, cross-sectional, questionnaire-based survey was carried out in 30 general hospitals dispersed in 30 provinces of mainland China (except for Tibet) during Oct 2015 to May 2016. Information of disease perception [Question 1: the disease nature of asthma; Question 2: medication choice of first-line in chronic asthma; Question 3: the occasion of using short-acting aerosols of receptor agonists; Question 4: perception of asthma treatment goal; Question 5: reason for not using peak flow meter (PFM)] were collected from asthma patients of outpatient department. These results were compared with the same type of survey results from 2007-2008. Results: Altogether 3 875 asthmatic outpatients were recruited. 69.0% (2 660/3 857) of the patients had right perception on the disease nature of asthma, 60.2% (2 321/3 857) of the patients considered inhaled corticosteroids (ICS)/inhaled corticosteroids plus long-acting beta2-agonists (ICS+ LABA) as daily-used first-line medication for chronic asthma. 85.7% (3 277/3 823) of the patients had right perception on the condition of using short-acting beta2-agonists (SABA). 75.4% (2 761/3 661) of the patients had right perception on asthma treatment goal. Only 10.1% (388/3 837) of the patients used PFM. Of the reasons for not using PFM, 65.2% (2 518/3 860) of the patients chose doctors never introduced. Among the 10 cities, which were also involved in the asthma control survey in 2007-2008, 71.1% (968/1 361) of the patients had right perception on the disease nature of asthma, 61.6% (839/1 362) of the patients considered ICS/ICS+ LABA as daily-used first-line medication for chronic asthma. 88.7% (1 207/1 361) of the patients had right perception on the condition of using SABA. 74.5% (1 013/1 360) of the patients had right perception on asthma treatment goal. 17.9% (244/1 360) of the patients used PFM. Of the reasons for not using PFM, 76.2% (931/1 221) of the patients chose doctors never introduced. Compared to the survey conducted in 2007-2008, the perception on disease nature and medication choice as daily-used first-line medication for chronic asthma significantly improved, the perception on occasion of using SABA and asthma treatment goal was comparable, while the rate of PFM usage showed no significant improvement. In reasons of not using PFM, doctors never introduced ranked the first. Conclusions: Compared to the similar survey conducted in 2007-2008, the overall status of disease perception of asthma patients has been improved in urban China, while the rate of PFM usage showed no significant improvement. Asthma education on asthma and asthma self-management should be further pushed forward.

[Trends of asthma control, disease management and perception in China].

Objective: To evaluate the changes of asthma control, disease management and perception in recent years in China. Methods: We conducted 2 multi-center, cross-sectional surveys. Outpatient asthmatic patients from 10 cities in mainland China (2007-2008) and 30 central cities from 30 provinces in China (except Tibet)(2015-2016) were recruited respectively. Data of asthma control, disease management and perception from the 2 surveys were compared for 10 cities which took part in both of the 2 surveys. Chi-square test was used for comparison between groups. Results: The asthma control level improved from 28.7%(839/2 928) in 2007-2008 to 39.2%(533/1 361) in 2015-2016(P<0.01). The rate of emergency visits was 18.2%(248/1 362) in 2015-2016, which was lower than that in 2007-2008(33.9%, 1 032/3 044)(P<0.01). The rate of peak flow meter (PFM) usage was 17.9%(244/1 360) in 2015-2016, which was slightly lower than the PFM usage rate in 2007-2008(21.8%, 660/3 030)(P=0.004). 56.0%(763/1 362) of the patients used inhaled corticosteroid (ICS) + formoterol to control asthma when asthma symptoms deteriorated in 2015-2016, which was higher than the result of 2007-2008(31.8%, 803/2 524)(P<0.01). 71.1%(968/1 361) of the patients in 2015-2016 had a right perception on disease nature, while the result in 2007-2008 was 63.3%(1 889/2 986)(P<0.01). 61.6%(839/1 362) of the patients in 2015-2016 had a right perception on medication choice on daily-use first-line medication for chronic asthma, while the result in 2007-2008 was 51.0%(1 500/2 942)(P<0.01). Conclusion: The current level of asthma control and disease perception in China improved significantly in recent years, while the rate of PFM usage showed no significant improvement. Asthma action plan including PFM monitoring and asthma self-management should be further promoted nationwide.

Polysynthetic twinned TiAl single crystals for high-temperature applications.

TiAl alloys are lightweight, show decent corrosion resistance and have good mechanical properties at elevated temperatures, making them appealing for high-temperature applications. However, polysynthetic twinned TiAl single crystals fabricated by crystal-seeding methods face substantial challenges, and their service temperatures cannot be raised further. Here we report that Ti-45Al-8Nb single crystals with controlled lamellar orientations can be fabricated by directional solidification without the use of complex seeding methods. Samples with 0° lamellar orientation exhibit an average room temperature tensile ductility of 6.9% and a yield strength of 708 MPa, with a failure strength of 978 MPa due to the formation of extensive nanotwins during plastic deformation. At 900 °C yield strength remains high at 637 MPa, with 8.1% ductility and superior creep resistance. Thus, this TiAl single-crystal alloy could provide expanded opportunities for higher-temperature applications, such as in aeronautics and aerospace.

First-principles computation of electron transfer and reaction rate at a perovskite cathode for hydrogen production.

The focus of this research is on the electron transfer and its reaction rate at the perovskite cathode of a photoelectrochemical cell for hydrogen production. By employing the density functional theory (DFT), the electron density, projected density of states (PDOS), electron distribution and electron transfer path between [Fe-Fe] hydrogenase and the perovskite cathode can be obtained. Simulation results show that the perovskite cathode is better than traditional cathodes for hydrogen production. Before transmission to the [Fe-Fe] hydrogenase, electron clouds mainly aggregate at the periphery of amine molecules. Simulations also show that the key to hydrogen production at the perovskite structure lies in the organic molecules. Electrons are transferred to the hydrocarbon structural chain before reaching the Fe atoms. The Rice, Ramsperger, Kassel and Marcus (RRKM) theory was used to predict the reaction rates at different temperatures. It was found that the reaction rates are in good agreement with the experimental results. This research provides more physical insight into the electron transfer mechanism during the hydrogen production process.

Effects of alendronate on osteoporosis treatment and levels of related cytokines.

Alendronate regulates the activity of osteoclasts and healing of osteoporosis. This study investigated the effect of alendronate on bone healing and changes in the levels of cytokines. Bilateral ovaries of 10 adult female rabbits were removed surgically in aseptic condition to establish the animal model of osteoporosis. Five rabbits in group A were treated with alendronate (1.15 mg·kg-1·week-1) once a week by a stomach tube, whereas the remaining 5 in group B were treated with physiological saline. The success of the animal model establishment and the efficacy of alendronate treatment were evaluated by the sports ability score and the Basso, Beattie, and Bresnahan (BBB) score; the healing degree of osteoporosis was determined by X-ray analysis and measurement of biomechanical properties; the changes in the levels of related cytokines were measured by enzyme-linked immunosorbent assay (ELISA) and immunohistochemical staining. Treatment improved dyskinesia of the animals in group A than that in group B, with significant improvement occurring in the 4th week of treatment. The BBB score of the group A animals revealed movements similar to normal, but that of the group B animals exhibited significant motor disturbance (P < 0.01). X-ray examination showed that with time, the X-ray ratings increased. Measurement of the biomechanical properties further showed that alendronate had a positive effect on osteoporosis healing. The results of ELISA and immunohistochemistry showed that the levels of ALP, BMP-2, bFGF, and IGF-1 were upregulated in group A. In conclusion, alendronate accelerated osteoporosis healing probably via certain cytokine-related mechanism.

[Chinese expert consensus for non-antiinfective effects and clinical use of macrolides].

Important/potential value of macrolides has been proved in the management of chronic respiratory diseases by increasing basic and clinical trials.Through three face-to-face discussions, 10 experts examined important data and drafted this consensus related to macrolides: (1) mechanism of non-antiinfective effects; (2) clinical use in chronic respiratory diseases; (3) cautions of long-term use.The mechanism out of non-antiinfective effects includes anti-inflammatory effect, modifying airway secretion, immune-regulation related to antibacterial effect, corticoid saving effect and anti-viral effect.The efficacy of long-term use of low-dose macrolides is definitely confirmed in diffuse panbronchiolitis, chronic rhinosinusitis. It is considerably used in bronchiectasia, cystic fibrosis, severe asthma and chronic obstructive pulmonary disease. Further studies should be conducted in cryptogenic organizing pneumonia and respiratory viral infection. It should be paid attention to its possible adverse effects (including drug interactions, cardiac toxicity, ototoxicity and disturbance of intestinal flora) and drug resistance in long-term use.A Chinese consensus for non-antiinfective effects and clinical use of macrolides is developed for the first time, which aims to expand their rational use and the further research.

[The relationship between smoking status and epidermiology of asthma in people aged over 14 years in China].

Objective: To study the relationship between bronchial asthma and smoking status in Chinese people. Methods: Asthma epidemiological survey and stratified-cluster-random method survey were performed in residents over 14 years in 8 provinces (cities) of China from February 2010 to August 2012. Asthma was diagnosed based upon case history, clinical signs and lung function test. Smoking status was investigated by questionnaire. Results: Sampling population was 180 099 and 164 215 were valid. A total of 2 034 subjects were diagnosed as asthma including 79 692 men and 84 523 women. The overall prevalence rate of asthma was 1.24% (2 034/164 215). Smokers were 23.8% (39 137/164 215) in the whole population. Smokers were 34.5% (702/2 034) in asthmatic patients, compared with 23.7% (38 435/162 181) in no-asthmatic population. The incidence of asthma was 1.79% and 1.06% in smokers and non-smokers respectively (P<0.001), suggesting that OR of smoking was 1.70 (95% CI 1.55-1.86, P<0.001). According to asthma control test (ACT) score, the level of asthma control in non smoking group was higher than that in smoking group(43.2% vs 35.3%). The times of hospitalization due to acute exacerbations(0.51 vs 0.41 events/person/year), total hospitalization rate(27.35% vs 20.12%), annual emergency room visits (0.80 vs 0.60 events/person/year) and emergency room visit rate (31.77% vs 24.47%) were all much higher in smoking asthmatic patients than those in non smoking asthmatic patients, indicating that the level of asthma control in smoking patients was significantly worse than in non smoking patients. Conclusions: The smoking rate in Chinese people over 14 years is still high. The prevalence rate of asthma in smokers is significantly higher than that of non-smokers. The level of asthma control in smokers is significantly worse than that in non smokers.

[Warning symptoms of asthma attack and asthma self-management: a national asthma control survey from China].

Objective: To investigate warning symptoms of asthma attack and evaluate asthma self-management status of asthma patients in urban China. Methods: A multi-center, cross-sectional, questionnaire-based survey was carried out from 30 general hospitals dispersed in 30 provinces of mainland China (except for Tibet) during Oct 2015 to May 2016. Information of frequency and warning symptoms of asthma attack, the time from warning symptoms to asthma attack, the impact of asthma attack and asthma self-management were collected from asthma patients of outpatient department. Results: Altogether 3 875 asthmatic outpatients were recruited. 78.1% (3 026/3 875) of the patients reported restriction of exercise and daily activities during asthma exacerbation. 82.5% (3 160/3 829) of the patients had warning symptoms before asthma attack, the most common warning symptoms were cough, chest tightness and shortness of breath. The median time from warning symptoms to asthma attack was 2 h, the mean time was 90 h. Only 4.4% (167/3 829) of the patients had definite confidence to control asthma when symptoms deteriorated. 76.7% (2 937/3 828) of the patients used medications to control asthma when asthma symptoms deteriorated. Medication choice: inhaled corticosteroid (ICS) + formoterol 45.8% (1 776/3 875), short-acting beta-agonist (SABA) 23.9% (927/3 875). Conclusions: Most asthma patients have warning symptoms before asthma attack, the most common symptoms are cough, chest tightness and shortness of breath. The proportion of patients conducting effective asthma self-management remains low.

[A multi-center study for the association between the perception and control of disease among asthmatic patients in Chinese urban areas].

Objective: To investigate the current perception of disease among asthmatic patients in Chinese urban areas, and to address its association with asthma control. Methods: This was a nationwide, multi-center, cross-sectional study covering 30 third-level, grade A hospitals in 30 provinces, municipalities and autonomous regions (not including Tibet) across Chinese mainland. The survey was carried out from October 2015 to May 2016. Asthmatic outpatients were selected to receive face-to-face questionnaire survey on asthma control including Asthma Control Test (ACT) score, classification of asthma control level[according to the Global Initiative for Asthma (GINA) 2015 classification system, as assessed by the physician completing the survey], perception of asthma (including question 1: nature of asthma as a disease; question 2: selection of first-line therapeutic agents to be regularly used daily for asthma; question 3: appropriate timing of the use of short-acting aerosols of ß(2) receptor agonists; and question 4: therapeutic goals for asthma). Results: A total of 3 875 asthmatic outpatients were included; among them, 69.0% (2 660/3 857) were aware that asthma is "an airway inflammatory disorder resulting from the combined effects of heredity and environment" ; 60.2% (2 321/3 857) considered "inhaled glucocorticoids or their compound preparations" to be the first-line therapeutic agents to be regularly used daily for patients with persistent chronic asthma; 85.7% (3 277/3 823) considered it appropriate to use short-acting aerosols of ß(2) receptor agonists "as needed in the event of disease aggravation or acute exacerbation" ; and 75.4% (2 761/3 661) were aware that asthma "can be adequately or completely controlled in the long term" . The ACT score[20 (16, 23) vs 19 (16, 22) points; Z=-3.928, P<0.001]and asthma control rate (29.92% vs 25.31%; χ(2)=8.616, P=0.003) were significantly higher, and the rate of uncontrolled asthma (19.92% vs 23.48%; χ(2)=6.267, P=0.012) was significantly lower among the 2 660 (69.0%) patients correctly answering question 1 than among the 1 197 (31.0%) patients giving incorrect answer. The ACT score[21 (17, 23) vs 19 (15, 22) points; Z=-9.190, P<0.001] and asthma control rate (32.66% vs 22.20%; χ(2)=49.614, P<0.001) were significantly higher, and the rate of uncontrolled asthma (18.40% vs 25.00%; χ(2)=24.267, P<0.001) was significantly lower among the 2 321 (60.2%) patient correctly answering question 2 than among the 1 536 (39.8%) patients giving incorrect answer. Conclusions: Compared to previous surveys, there has been improved perception of disease among asthmatic patients in Chinese urban areas. Correct perception of disease is favorable for improving asthma control level.

[The level of asthma control in China from a national asthma control survey].

Objective: To assess the overall asthma control level in urban China. Methods: A multi-center, cross-sectional, questionnaire-based survey was carried out in 30 provinces in China (except Tibet). Asthmatic outpatients who met the inclusion criteria were recruited consecutively from 30 sub-centers from October 2015 to May 2016. Data of demographic characteristics, asthma control, asthma management, asthma exacerbations and self-management, and disease perception were collected by face-to-face interviews. Results: Totally 3 875 asthmatic outpatients were recruited. Asthma control level was assessed according to GINA 2015. The prevalence of asthma control was 28.5%(1 099/3 854). Among 10 cities, which were also involved in the asthma control survey in 2008, the level of asthma control improved from 28.7% in 2008 to 39.2%(533/1 361) in 2016. The rate of hospitalizations due to asthma exacerbations was 26.4%(1 017/3 858) and the rate of emergency visits was 22.4%(864/3 858). Among adult patients, 18.4%(568/3 092) of them had been absent from work while 63.6%(63/99) adolescent patients had been absent from school because of asthma attacks in the previous year. Conclusion: Although the level of asthma control in China is still far from ideal at present, the status has been improved in some cities. Poorly controlled asthma resulted in increase of hospitalizations, emergency department visits and work/school absences.