Real-Time Structural Monitoring of the Multi-Point Hoisting of a Long-Span Converter Station Steel Structure.

In the process of using a long-span converter station steel structure, engineering disasters can easily occur. Structural monitoring is an important method to reduce hoisting risk. In previous engineering cases, the structural monitoring of long-span converter station steel structure hoisting is rare. Thus, no relevant hoisting experience can be referenced. Traditional monitoring methods have a small scope of application, making it difficult to coordinate monitoring and construction control. In the monitoring process, many problems arise, such as complicated installation processes, large-scale data processing, and large-scale installation errors. With a real-time structural monitoring system, the mechanical changes in the long-span converter station steel structure during the hoisting process can be monitored in real-time in order to achieve real-time warning of engineering disasters, timely identification of engineering issues, and allow for rapid decision-making, thus avoiding the occurrence of engineering disasters. Based on this concept, automatic monitoring and manual measurement of the mechanical changes in the longest long-span converter station steel structure in the world is carried out, and the monitoring results were compared with the corresponding numerical simulation results in order to develop a real-time structural monitoring system for the whole long-span converter station steel structure's multi-point lifting process. This approach collects the monitoring data and outputs the deflection, stress, strain, wind force, and temperature of the long-span converter station steel structure in real-time, enabling real-time monitoring to ensure the safety of the lifting process. This research offers a new method and basis for the structural monitoring of the multi-point hoisting of a long-span converter station steel structure.

[The Preliminary Study on Anti-photodamaged Effect of Astaxanthin Liposomes in Mice Skin].

OBJECTIVE: To study the protective effects of astaxanthin liposome (Asx-lipo) on photodamage by UVB in mice skin. METHODS: 40 C57BL/6J mice were randomly divided into four groups: The blank group (no irradiation, no drug use), model group (UVB light injury group, no drug use), control group (irradiation + astaxanthin), experimental group (irradiation + astaxanthin liposome), each group with 10 mice. Each group was given the corresponding light (the radiation intensity was 2 mW·cm2, the time of irradiation was 60 s, 1 times a day for the first 5 days, and 1 times every other day for the next 9 days, 10 times in a total of 2 weeks.) and drug intervention (topically treated with 4 mL 0.2‰ astaxanthin or 4 mL 0.2‰ Asx-lipo 10 min before the irradiation) for two weeks. After that, samples were examined by the following indicators: the histological changes of skin, Ki-67, 8-hydroxy-2'-deoxyguanosine(8-OHdG), superoxide dismutase(SOD) activities and serum matrix metalloproteinase-13 (MMP-13). RESULTS: HE staining the model group and the control group showed that the dermis became thin, the dermal collagen fibers were long and thin, and the arrangement was loose and disordered. Compared with the blank group, the expression of Ki-67, MMP-13 and 8-OHdG increased and SOD activity decreased, and the differences were statistically significant (P<0.05). Compared with the model group, the pathological changes of skin tissues in the experimental group were significantly improved, with decreased expressions of Ki-67, MMP-13 and 8-OHdG and increased SOD activity, and the differences were statistically significant (P<0.05). CONCLUSION: The photodamage of mice skin can be improved by topical Asx-lipo. The mechanism may be related to the strong antioxidation of Asx-lipo.

Characterization of solid dispersions of Patchouli alcohol with different polymers: effects on the inhibition of reprecipitation and the improvement of dissolution rate.

Solid dispersion technique is known to be an effective approach for the polymer to keep drugs stable in the solid state, thereby improving the dissolution rate and oral bioavailability through inhibiting reprecipitation in supersaturated solution. In this study, to evaluate the inhibitory effect of polyethylene glycol-6000 (PEG), Polyvinylpyrrolidone K30 (PVP) and Aminoalkyl methacrylate copolymer (Eudragit), the reprecipitation profiles were observed from supersaturated solutions of Patchouli alcohol (PA) in the presence and absence of the polymers. Furthermore, the dissolution profiles of PA solid dispersions formulated with PEG, PVP or Eudragit were compared for investigating the effect on improving dissolution of each polymer. Solid dispersions formulated with Eudragit were found to result in solution with the highest extent of supersaturation. By contrast, PEG and PVP were less effective. At equivalent supersaturation, all three polymers are capable of mitigating reprecipitation relative to that of PA alone. In addition, in the PA solid dispersion with Eudragit (E-SD (1/3)), the highest concentration of supersaturation of PA was maintained for prolonged time. These results unambiguously indicate that it is imperative to select the appropriate polymer and drug/polymer ratio in addition to considering the stability of the supersaturated solution, which was generated following dissolution of amorphous solid dispersion.

[HBeAg seroconversion achieved by sequential peginterferon alfa-2a therapy in chronic hepatitis B patients with unsatisfactory end point following entecavir treatment].

OBJECTIVE: To investigate the efficacy and safety of peginterferon alfa-2a (Peg-IFNa-2a) therapy for treating chronic hepatitis B (CHB) in patients who failed to achieve a satisfactory end point with entecavir (ETV) treatment. METHODS: Fifty-seven CHB patients with positivity for hepatitis B e antigen (HBeAg) who had completed a standard ETV monotherapy course, of at least 96 weeks, and who had achieved a virological response (defined as HBV DNA less than 500 copies/ml) but without HBeAg seroconversion (defined as 0.227 PEI U/ml less than HBeAg less than or equal to 50 PEI U/ml) were enrolled in the study. The patients were randomly assigned to receive a 48-week treatment with Peg -IFNa-2a (experimental group, n = 27) or continued ETV therapy (control group, n = 30). Serum samples were collected from all patients for assessment of biochemical, virological and serological responses to treatment. Inter-group differences were statistically evaluated by t-test or Chi-squared test. RESULTS: The baseline levels of alanine aminotransferase, hepatitis B surface antigen (HBsAg), and HBeAg were similar between the patients comprising the experimental and controls groups. At treatment week 48, the experimental group showed significantly higher rates of HBeAg clearance (Peg-IFNa-2a: 40.7% vs. ETV: 16.7%, x2 = 4.079, P less than 0.05) and seroconversion (37.0% vs. 13.3%, x2 = 5.110, P less than 0.05). The experimental group also showed higher rates of HBsAg clearance (7.4% vs. 0%) and HBV DNA relapse (11.1% vs. 0%), but the differences did not reach statistical significance (x2 = 2.307 and 3.519, both P more than 0.05). However, the level of HBsAg was significantly lower in the experimental group (2866.0+2580.4 vs. 4335.8+2650.0 IU/ml, t = 5.11, P less than 0.05). CONCLUSION: HBeAg-positive CHB patients with unsatisfactory response to initial ETV monotherapy achieved HBeAg seroconversion and clearance following sequential Peg-IFN a-2a treatment.

Biodegradable plastics in the air and soil environment: Low degradation rate and high microplastics formation.

In recent years, the promotion and use of biodegradable plastics (BPs) are growing into a general trend. Here the degradation performance of different types of BPs was investigated in the natural environment. Their degradation levels followed the order of pure BPs> BP blends> claimed "BP"≈ non-biodegradable plastic after 6-month incubation. Photo- and biodegradation were the main degradation mechanisms of these plastics in the air and soil, respectively. Poly(p-dioxanone) (PPDO) exhibited the highest weight loss potentials in both air (54.7 ± 9.1%) and soil (56.8 ± 4.8%), due to its special ether bond and the rich and diverse microorganisms on its biofilms. The microbiota on PPDO was distinct and enriched with Chloroflexi and Firmicutes that responsible for carbon cycle and organic degradation. The weight loss was only 1.1-8.0% for poly(lactic acid), and 0.8-6.8% for poly(butylene adipate-co-terephthalate), and other plastics are basically non-degradable. Of note, numerous microplastics were formed after PPDO degradation, with 441 ± 326 and 2103 ± 131 item/g plastic in the air and soil, respectively. Taken together, the monitoring of BP biodegradation in the natural environment is of vital importance, and it is risky to promote large-scale application of BPs if the knowledge gap of their environmental behavior has not been well addressed.

Synthesis, characterization, and application of reversible PDLLA-PEG-PDLLA copolymer thermogels in vitro and in vivo.

In this study, a series of injectable thermoreversible and thermogelling PDLLA-PEG-PDLLA copolymers were developed and a systematic evaluation of the thermogelling system both in vitro and in vivo was performed. The aqueous PDLLA-PEG-PDLLA solutions above a critical gel concentration could transform into hydrogel spontaneously within 2 minutes around the body temperature in vitro or in vivo. Modulating the molecular weight, block length and polymer concentration could adjust the sol-gel transition behavior and the mechanical properties of the hydrogels. The gelation was thermally reversible due to the physical interaction of copolymer micelles and no crystallization formed during the gelation. Little cytotoxicity and hemolysis of this polymer was found, and the inflammatory response after injecting the hydrogel to small-animal was acceptable. In vitro and in vivo degradation experiments illustrated that the physical hydrogel could retain its integrity as long as several weeks and eventually be degraded by hydrolysis. A rat model of sidewall defect-bowel abrasion was employed, and a significant reduction of post-operative adhesion has been found in the group of PDLLA-PEG-PDLLA hydrogel-treated, compared with untreated control group and commercial hyaluronic acid (HA) anti-adhesion hydrogel group. As such, this PDLLA-PEG-PDLLA hydrogel might be a promising candidate of injectable biomaterial for medical applications.

[Reconstruction of the mandibular model using a three-dimensional laser scanner].

OBJECTIVE: To construct a three-dimensional (3D) mandibular model using a 3D laser scanner, and explore a new method for reconstructing the finite element geometry model. METHODS: A mandible specimen was scanned with the 3D laser scanner to form the point clouds of the mandibular surface, which were subsequently aligned for reconstruction of the mandibular model. RESULT: A 3D model of the mandible surface was reconstructed, which could be used for finite element simulation. CONCLUSION: The 3D laser scanning system can be used to reconstruct the 3D model with irregular geometry for finite element simulation.

Prevention of postsurgical cauterization-induced peritoneal adhesions by biodegradable and thermosensitive micelles.

Postsurgical peritoneal adhesion is a major concern in clinical practice which causes significant morbidity and mortality. In this study, we investigated the efficacy of biodegradable and injectable thermosensitive poly(ethylene glycol)-poly(epsilon-caprolactone)-poly(ethylene glycol) (PEG-PCL-PEG) micelles in preventing postsurgical cauterization-induced peritoneal adhesion. The biodegradable PEG-PCL-PEG copolymer could form nano-sized micelles in water, which instantly turned into a non-flowing gel at body temperature due to micellar aggregation. Moreover, a novel sidewall and cecum cauterization rat model was developed and the micelles were assigned for adhesion prevention tests. The PEG-PCL-PEG micelles could be administered by an ordinary syringe and provided unrestricted coverage of the cauterized peritoneum. The micelles instantly formed a gel in situ at body temperature and the formed gel could adhere to the cauterized sites as a durable barrier during critical time of adhesion formation. All rats from the control group (n = 10) developed score 5 adhesion, whereas, eight out of ten rats in the micelle-treated group showed no adhesion at all. Besides, cauterization-induced adhesion formation, adhesiveness and degradation of micelles, remesothelization of peritoneum, and restoration of cauterized tissue were investigated in detail. Our results thus indicated that, it was feasible to use biodegradable and injectable thermosensitive PEG-PCL-PEG micelles for prevention of peritoneal adhesions after surgery.

Highly catalytic carbon nanotube/Pt nanohybrid-based transparent counter electrode for efficient dye-sensitized solar cells.

Low-cost transparent counter electrodes (CEs) for efficient dye-sensitized solar cells (DSSCs) are prepared by using nanohybrids of carbon nanotube (CNT)-supported platinum nanoparticles as highly active catalysts. The nanohybrids, synthesized by an ionic-liquid-assisted sonochemical method, are directly deposited on either rigid glass or flexible plastic substrates by a facile electrospray method for operation as CEs. Their electrochemical performances are examined by cyclic voltammetry, current density-voltage characteristics, and electrochemical impedance spectroscopy (EIS) measurements. The CNT/Pt hybrid films exhibit high electrocatalytic activity for I(-)/I(3)(-) with a weak dependence on film thickness. A transparent CNT/Pt hybrid CE film about 100 nm thick with a transparency of about 70% (at 550 nm) can result in a high power conversion efficiency (η) of over 8.5%, which is comparable to that of pyrolysis platinum-based DSSCs, but lower cost. Furthermore, DSSC based on flexible CNT/Pt hybrid CE using indium-doped tin oxide-coated polyethylene terephthalate as the substrate also exhibits η=8.43% with J(sc)=16.85 mA cm(-2), V(oc)=780 mV, and FF=0.64, and this shows great potential in developing highly efficient flexible DSSCs.