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With the success of bringing back lunar samples, Mars exploration and space station construction, new requirements for high performance materials were put forward with the devel-opment of China's new space missions. Based on the analysis of the current situation and trend of China's aerospace development, some demands for high performance materials such as lightweight high performance structural materials, lightweight high efficiency thermal protection materials, structural & functional integration materials, new multifunctional composite protective materials, extreme temperature resistant functional materials, intelligent materials, high performance spacesuit materials, functional gradient materials, meta-materials, 3D printing materials and 4D printing materials were analyzed. Finally, nanotechnology, material genetic engineering and other new technologies were put forward to incorporate the space environment into the whole process of aerospace materials development and to further carry out the research and development of aerospace materials.

HZSM-5 supported SrTiO3 was prepared using sol-gel method. The materials were characterized by XRD, SEM, BET, BJH and FT-IR measurements. The activity of photocatalytic degradation of reactive brilliant red X-3B was studied on SrTiO3/HZSM-5. The results show that SrTiO3 material is mainly composed of perovskite SrTiO3, as well as a small amount of SrCO3 phase. SrTiO3 is coated on the external surface of HZSM-5 in the χSrTiO3/HZSM-5. The specific surface area of the supported materials is mainly provided by the zeolite, while pore size in the materials is mainly in the range between 2-20nm. Photocatalytic activity of SrTiO3 is obviously enhanced after being supported, and the 30%SrTiO3/HZSM-5 has the maximum activity. 93.8% of reactive brilliant red X-3B can be degraded on 30%SrTiO3/HZSM-5 after 90 minites irradiation, while only 23.9% of the dye can be degraded on pure SrTiO3.

We used surface thermal lensing (STL) to measure the weak absorption of optical films. Different trends of STL phase signals were observed in films with two types of defect, i.e., absorptive defects and heat-resistant defects. Theoretical analysis was made, and it is in good agreement with the experimental results. Therefore, an enhanced STL technique is proposed to deduce both the magnitude of absorption and the type of defect in optical films, by considering signal intensity with its phase status. [c] 2010 Optical Society of America OCIS codes: 310.6870, 350.5340.

To deduce the location of absorptive inclusions in thin films, temperature distributions in pure Ti[O.sub.2] films and Ti[O.sub.2] films with high-absorptance inclusions are analyzed based on temperature field theory. According to our theoretic simulations, the surface temperature rise increases when absorptive inclusions are incorporated into thin films and shows different values for different inclusions. With the increase of inclusion thickness, the surface temperature rise varies and has a maximum value. A potential method is presented to deduce the location of absorptive inclusion through calculating the surface temperature rise at two modulated frequencies, if it is possible to know in advance the inclusion material or to prejudge this from a thin-film deposition process. [c] 2010 Optical Society of America OCIS codes: 310.6870, 140.6810.

A method is presented to evaluate optical absorption at a random wavelength by calculating temperature distribution in single-layer Ti[O.sub.2] films. Temperature distribution in single-layer Ti[O.sub.2] films was analyzed based on temperature field theory. Through our calculations, optical absorption variation was obtained to be similar to that of surface temperature rise in films. The surface temperature rise depends on film thickness, refractive index, extinction coefficient, specific heat, and thermal conductivity. Furthermore, the optical absorptions of the same single-layer Ti[O.sub.2] film at different wavelengths were deduced. As an example, the surface temperature rises were calculated for the 19 single-layer Ti[O.sub.2] films, which had been prepared by 12 different laboratories for the annual meeting of the Optical Society of America in 1986. The results agree well with the measured optical absorptions. OCIS codes: 310.4925, 240.0310.

The Clavien-Dindo (C-D) classification is a simple and feasible grading system of postoperative complications. The aim of the present study was to apply this system to retrospectively classify all types of post-pancreaticoduodenectomy (PD) complications (PPCs) and to systematically identify associated risk factors. Between January 2009 and December 2014, the C-D classification was applied to retrospectively classify PPCs for 1,056 patients who had undergone PD at the West China Hospital. Univariate and multivariate analyses were performed to link perioperative parameters and mortality with the severity of PPCs, which were subdivided into overall PPCs (Grade I-V), severe PPCs (Grade III-V) and mortality (Grade V). The number of patients with Clavien-Dindo grade I, II, IIIa, IIIb, IVa, IVb and V complications was 185 (17.5%), 128 (12.1%), 50 (4.7%), 25 (2.4%), 35 (3.3%), 19 (1.8%) and 33 (3.1%), respectively. A total of 475 (45.0%) patients experienced overall PPCs; 168 (15.9%) patients experienced severe PPCs; and 33 patients succumbed to mortality following PD. The following risk factors were identified following PD: Preoperative hypoproteinemia was correlated with all three subdivisions; obstructive jaundice was associated with severe PPCs and mortality; and older age was revealed to be an independent risk factor of mortality. A large retrospective study was performed in the present study and PD was correlated with a high occurrence of PPCs. The Clavien-Dindo system represents a broad applicable and feasible approach to evaluating PPCs in patients following PD. The independent risk factors of PPCs that were identified in the present study require further validation using the Clavien-Dindo classification in additional prospective studies. [ABSTRACT FROM AUTHOR]

Aim: To investigate the accuracy of Endoscopic ultrasound (EUS) in staging and sub-staging T1a and T1b esophageal squamous cell carcinoma (ESCC)., Methods: A retrospective analysis involving 72 patients with pathologically confirmed T1a or T1b ESCC, was undertaken between January 2005 and December 2011 in Sun Yat-sen University Cancer Center. The accuracy and efficiency of EUS for detecting stages T1a and T1b ESCC were examined., Results: The overall accuracy of EUS for detecting stage T1a or T1b ESCC was 70.8% (51/72), and the sensitivity was 74.3%. 77.8% (7/9) of lesions originated in the upper thoracic region, 73.1% (38/52) in the mid-thoracic region and 72.7% (8/11) in the lower thoracic region. Multivariate analysis revealed that the diagnostic accuracy of EUS was closely related to lesion length (F = 4.984, P = 0.029)., Conclusion: EUS demonstrated median degree of accuracy for distinguishing between stages T1a and T1b ESCC. Therefore, it is necessary to improve EUS for staging early ESCC.

Aim: To determine if there is consistency between endoscopic ultrasound (EUS) findings and pathological results for detecting lesions of different depth in the esophageal mucosa., Methods: A canine (Beagle) model was established in which lesions of different depths were created in the esophageal mucosa by thermal burning. Seventy-two hours later, these lesions and adjacent tissue in the esophagus were examined by EUS. EUS findings including infiltrating depth, strength of echogenicity and homogeneity were recorded. Dogs were sacrificed and tissue specimens were obtained. We then compared the EUS findings with the pathology reports., Results: Thermal burns created at different power settings caused lesions of different depth in the esophageal mucosa. When the echo strength was shifted from high, medium, to low echogenicity, an increase in the infiltrating depth of the lesion was noted, which coincided with results of the pathology examination. Obvious submucosal edema visualized by EUS was also detected by pathology. Furthermore, because of the enhancement caused by the submucosal edema, the lesions invading into the submucosa were easily visualized by EUS., Conclusion: There is consistency between EUS findings and pathological results of esophageal lesions with different depths. Submucosal edema can serve as an ultrasonic contrast agent.

Objective: To compare the values of measurements of obesity, including body mass index(BMI), waist circumference (WC), waist-to-hip ratio (WHR), bioelectrical impedance analyzer(BIA) (fat mass and FAT%), ultrasonography (US) (subcutaneous fat distance and intraabdominal fat distance), and computed tomography (CT) in predicting the quantification of visceral adipose in abdominal obesity, and to evaluate the best cut-off point, sensitivity and specificity of these methods., Methods: 4,301 inpatients with hypertension, 2,155 males and 2,146 females, aged (56.4 +/- 13.8) (11 - 89), all with at least 1 risk factor of cardiovascular diseases, underwent simple body fat measurement. 3458 received BIA, 2,553 received B mode ultrasonography, 1039 underwent CT examination, and 659 received all kinds of examination. Abdominal visceral adipose area (VA) measured with CT >or= 100 cm(2) was the diagnostic criteria of visceral fat obesity (VFO). Receiver operating characteristic (ROC) curve was used to analyze the body fat indexes to determine the best cut-off point., Results: (1) It was accurate for WC, fat mass, BMI, intraabdominal fat distance, FAT%, and WHR were all accurate in diagnosis of VFO with the values of area under ROC of 0.730 - 0.867. WC was the most effective measurement. (2) The best cut-off points of these methods in predicting abdominal visceral obesity in males and females were as follows: WC: 89.5 cm and 85.5 cm for WC. 25 kg/m(2) and 26 kg/m(2) for BMI, 0.97 and 0.95 for WHR, 29% and 38% for fat composition, 18.6 kg, and 20.4 kg for fat mass, and 38.5 mm and 34.7 mm for intraabdominal fat distance., Conclusions: WC, fat mass, BMI, intraabdominal fat distance, simple fat parameters, and WHR all can predict visceral adipose in abdominal obesity, in which WC is the best. For a given WC, the type of obesity can be determined by BIA and US.

Objective: To explore the relationship of different types of abdominal obesity to risk of metabolic syndrome (MS)., Methods: Visceral fat area (VA) and substantial fat area (SA) were assessed by CT in 846 patients, 470 males and 376 females, aged 55 +/- 12, who suffered from at least one cardiometabolic risk factor and divided into 4 groups according to their VA and waist circumference (WC): non-obesity, masked visceral fat obesity (VFO), pseudo-VFO, and VFO groups. Blood pressure, fasting blood glucose, fasting serum insulin, and lipid profile were also measured. The MS risks of different types of abdominal obesity were compared., Results: The prevalence rate of masked VFO of males was 10.9% (51/470), significantly higher than that of female (4.8%, 18/376). The prevalence rate of MS of the male patients with masked VFO was 43.1%, significantly higher than that of those in non-obesity group (25.0%), and lower than those of the males in the pseudo-VFO group (78.7%) and in the VFO group (88.6%), whereas the MS prevalence rate of the males in the pseudo-VFO group was significantly higher than those in the non-obesity and masked VFO groups. On the other hand, the MS prevalence rate of the female patients with masked VFO was 33.3%, not significantly different from that of the female patients in the non-obesity group (31.2%), but significantly lower than those of the pseudo-VFO and VFO groups (78.7% and 90.9% respectively). The MS prevalence rate of the female pseudo-VFO patients was also significantly higher than those in the non-obesity and masked VFO groups. Logistic regression analysis showed that WC and VA were independent risk factors for MS [OR (95% CI) = 1.13 (1.10-1.17), 1.01 (1.01-1.02), respectively, P < 0.01)., Conclusion: Different types of abdominal obesity have important impacts on the risk of metabolic syndrome. Masked VFO, even though with normal WC, and pseudo-VFO have considerably higher cardiometabolic risks.