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A dynamically reconfigurable liquid crystal (LC) photonic device is an important research field in modern LC photonics. We present a type of continuously tunable distributed Bragg reflector (DBR) based on LC polymer composites modulated via a novel optofluidic method. LC-templated DBR films are fabricated by photopolymerization under visible standing wave interference. The influences of the incident angle, incident light intensity, and content of ethanol as a pore-forming additive on the reflection behavior are discussed in detail. Then, the LC-templated DBR films are integrated into microfluidic channels and reversibly refilled by different organic solvents. The reconfigurable characteristics of optofluidic DBRs were demonstrated by changing the average refractive index (RI) of the mixed liquids and adjusting the flow rates, resulting in the dynamic and continuous variation of the reflection band within a specific visible light band. It is anticipated that the prototype optofluidic LC device will hopefully be applied to some specific scenarios where conventional means of regulation, such as electric, optical, and temperature fields, are unsuitable and possibly boost the development of microfluidic analysis techniques based on structural color.

Using export data with 6-digit HS categories for 1995-2018, we decompose China’s export growth into three margins: extensive (EM), price (PM), and quantity (QM). Our estimations suggest that over t...

Background: ABCG2 plays a critical role in multi-drug resistance in a variety of cancers. Its activity is influenced by ATP hydrolysis and substrate transport, which are synergistic processes but in two independent sites. However, there was no QSAR study of the ABCG2 inhibitors for the two binding sites respectively. Methods: in current study, a QSAR model of ATP binding site was built using DCG scoring strategy, it was used to optimize the structure of a tyrosine kinase inhibitor to avoid the potential drug resistance. Results: a series of novel dual target compounds with arylamide skeleton were obtained, which showed notable activity in enzyme activity test. Compound 7c and 7i showed significant inhibitory activity against drug-resistant cells. Conclusions: the QSAR of ATP binding site of ABCG2 was first discussed, the dual-target compound 7c proposed a new strategy to reverse drug resistance.

C-Met plays a crucial role in the development and progression of neoplastic disease. Type II c-Met inhibitors recognise the inactive DFG-out conformation of the kinase, result in better anti-tumour effects due to synergistic effect against the other kinases. According to our previous works, an (E)-N'-benzylidene group was selected as the initial fragment. Two series of (E)-N'-benzylidene hydrazides were designed by fragment growth method. The inhibitory activities were in vitro investigated against c-Met and VEGFR-2. Compound 10b exhibited the most potent inhibitory activity against the c-Met inhibitor (IC50 = 0.37 nM). Compound 11b exhibited multi-target c-Met kinase inhibitory activity as a potential type II c-Met inhibitor (IC50 = 3.41 nM against c-Met; 25.34 nM against VEGFR-2). The two compounds also demonstrate the feasibility of fragment-based virtual screening method for drug discovery.

Cyclin-dependent kinase 2 (CDK2) is the family of Ser/Thr protein kinases that has emerged as a highly selective with low toxic cancer therapy target. A multistage virtual screening method combined by SVM, protein-ligand interaction fingerprints (PLIF) pharmacophore and docking was utilised for screening the CDK2 inhibitors. The evaluation of the validation set indicated that this method can be used to screen large chemical databases because it has a high hit-rate and enrichment factor (80.1% and 332.83 respectively). Six compounds were screened out from NCI, Enamine and Pubchem database. After molecular dynamics and binding free energy calculation, two compounds had great potential as novel CDK2 inhibitors and they also showed selective inhibition against CDK2 in the kinase activity assay.

Phosphoinositide 3 kinase delta (PI3K&delta, ) is a lipid kinase that has been implicated in a variety of immune mediated disorders. The research on isoform selectivity was crucial for reducing side effects. In the current study, an optimized hierarchical multistage virtual screening method was utilized for screening the PI3K&delta, selective inhibitors. The method sequentially applied a support vector machine (SVM), a protein ligand interaction fingerprint (PLIF) pharmacophore, and a molecular docking approach. The evaluation of the validation set showed a high hit rate and a high enrichment factor of 75.1% and 301.66, respectively. This multistage virtual screening method was then utilized to screen the NCI database. From the final hit list, Compound 10 has great potential as the PI3K&delta, inhibitor with micromolar inhibition in the PI3K&delta, kinase activity assay. This compound also shows selectivity against PI3K&delta, kinase. The method combining SVM, pharmacophore, and docking was capable of screening out the compounds with potential PI3K&delta, selective inhibitors. Moreover, structural modification of Compound 10 will contribute to investigating the novel scaffold and designing novel PI3K&delta, inhibitors.

Objective: To explore the effect of mild hypothermia intervention on the nerve injury as well as neurotransmitters and inflammatory mediators in patients with acute craniocerebral injury. Methods: A total of 700 patients with acute craniocerebral injury who were treated in Lueyang People’s Hospital between March 2014 and March 2017 were collected and divided into routine group (n=350) and mild hypothermia group (n=350) by random number table. Routine group accepted craniotomy evacuation of hematoma, and mild hypothermia group accepted mild hypothermia intervention on the basis of craniotomy evacuation of hematoma. The differences in the serum contents of nerve injury-related indexes, amino acid neurotransmitters and inflammatory mediators were compared between the two groups before and after treatment. Results: Before treatment, there was no statistically significant difference in the serum levels of nerve injury-related indexes, amino acid neurotransmitters and inflammatory mediators between the two groups. After treatment, serum nerve injury-related indexes NSE, S100B, Nogo-A and MBP levels of mild hypothermia group were lower than those of routine group; serum amino acid neurotransmitters Asp and Glu levels of mild hypothermia group were lower than those of routine group while GABA level was higher than that of routine group; serum inflammatory mediators HMGB1, IL-8 and TNF-α levels of mild hypothermia group were lower than those of routine group. Conclusion: Early mild hypothermia intervention can effectively relieve the nerve injury in patients with acute craniocerebral injury and exert positive neuroprotective effect.

A series of imidazolium salt derivatives have demonstrated potent antitumor activity in prior research. A comprehensive in silicon method was carried out to identify the putative protein target and detailed structure-activity relationship of the compounds. The Topomer CoMFA and CoMSIA techniques were implemented during the investigation to obtain the relationship between the properties of the substituent group and the contour map of around 77 compounds; the Topomer CoMFA and CoMSIA models were reliable with the statistical data. The protein–protein interaction network was constructed by combining the Pharmmapper platform and STRING database. After generating the sub-network, the phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA with protein data bank ID: 3ZIM) was selected as the putative target of imidazolium salt derivatives. A docking study was carried out to correlate interactions of amino acids in protein active pockets surrounded by the ligand with contour maps generated by the structure-activity relationship method. Then the molecular dynamics simulations demonstrated that the imidazolium salt derivatives have potent binding capacity and stability to receptor 3ZIM, and the two ligand-receptor complex was stable in the last 2 ns. Finally, the ligand-based structure-activity relationship and receptor-based docking were combined together to identify the structural requirement of the imidazolium salt derivatives, which will be used to design and synthesize the novel PIK3CA inhibitors.

A damage detection method for complex structures is proposed based on model updating and modal flexibility curvature difference in this paper, which includes two steps. At first, the model updating is used for preparatory detection. In the step, detection problem is transformed into an optimization problem by a nonlinear least-square objective function with bound constrains and the trust-region approach is used to solve the minimization problem and identify the damaged unit group. Second, the method based on modal flexibility curvature difference is used to detect the location of structural damage accurately. In order to verify the effect, simulation and experiment on a framework structure are carried out. The proposed method is applied for damage detection. The simulation and experimentation results show that the proposed method is feasible for damage detection on complex structures.

The luminescent properties of the phosphor screen of LLL image intensifier has a very close correlation with the performance of the LLL image intensifier. As for the research status of luminescent properties of phosphor screen of the LLL image intensifier, the test, analysis and evaluation research for the various performance parameters of its light-emitting properties, such as luminous efficiency, resolution, are relatively independent, which is not conducive to the overall performance evaluation of a phosphor screen. In view of this, on the basis of the analysis of the correlation between LLL image intensifier performance and the phosphor screen performance, and according to the concept of figure of merit (FM) of LLL image intensifier, a new FM concept of the phosphor screen is proposed. By the relevant experiments, the FM expression of a phosphor screen under different technical and excitation conditions was obtained. The performance of the phosphor screen can be evaluated intuitively and comprehensively by means of FM of the phosphor screen. The performance evaluation contributes to the in-depth study on FM of the LLL image intensifier.

The worm auger contributes to the pressures generated at the grinder plate face during grinding of meat. The axial pressure distribution along the worm auger during grinding was discussed. The pressure almost increased linearly along axial direction from feeding end to discharge end. The 3D model of the worm auger created in Pro/E software were imported into ANSYS 9.0 software and a linear static finite element analysis was performed. The visual deflection patterns the part experiences under "real world" loading conditions were obtained so as to complete the security check of strength. The results showed that the yield strength was largely improved with thread root radius increasing from 2 mm to 5 mm. Hence, this method can be applied to rapidly and correctly find those dangerous positions and existing imperfections of its structure, thus providing valuable data to judge its structural rationality before practical manufacture, so as to make further improvements and optimizations for its structural design.

Screw pressing technology provides a pressing process superior to those traditional ones. Screw press has been used in oil extraction with a long history, both for cold and hot pressing of vegetable oil materials. Pressing screw is the core component of screw press, as a very important working part, its strength is a precondition for ensuring normal operation of the whole machine. Considering the complexity and drawbacks of conventional analysis and check methods for pressing screw, a simplified three-dimensional model of which was set up, then finite element analysis was done, thus obtaining its continuous deformation and stress distribution with the results close to those from theoretical calculation. Hence, this method can be applied to rapidly and correctly find those dangerous positions and existing imperfections of its structure, thus providing valuable data to judge its structural rationality before practical manufacture, so as to make further improvements and optimizations for its structural design.

In this paper, a liquid refractive index (LRI) measurement system based on an electrowetting lens was proposed. The system is composed of a light source, a collimating lens, a liquid measurement chamber (LMC), an electrowetting lens and an image sensor, which is integrated into a cylindrical cavity. The refractive index of the LMC changes with the addition of the measured liquid, and the incident light cannot be focused on the image plane. By adjusting the driving voltage of the electrowetting lens, the curvature of the liquid-liquid interface changes to focus the incident light onto the image plane. The refractive index of the liquid could be measured according to the voltage value. The proposed LRI measurement system has no mechanical moving parts, and the imaging surface remains stationary, which can make the measurement simply and correctly. The experiments show that the refractive index measurement range of the system can be turned from ~1.3300 to ~1.4040, and the measurement accuracy is 10&minus, 4. The system can be used to measure the optical properties of liquids and has broad potential applications in chemical reagent detection and pharmaceutical testing.

The grinder perforated plate with bone-removal systems has a unique design to improve the quality of ground meat. The pressure distribution on the grinder knife/plate interface during grinding of meat was investigated. The peripheral pressure on meat grinder plates during operation was greater than at the center thus hard particles are collected at the low pressure point. The mechanical models on the perforated plate surface created in MATLAB 7.0 for linear programming, and the 3D model of the perforated plate created in Pro/E software were imported into ANSYS 9.0 software and a linear static finite element analysis was performed. The visual deflection patterns the part experiences under "real world" loading conditions were obtained so as to complete the security check of strength.

We evaluated the use of a combination of human insulin gene-modified umbilical cord mesenchymal stromal cells (hUMSCs) with silk fibroin 3D scaffolds for adipose tissue engineering. In this study hUMSCs were isolated and cultured. HUMSCs infected with Ade–insulin–EGFP were seeded in fibroin 3D scaffolds with uniform 50–60 µm pore size. Silk fibroin scaffolds with untransfected hUMSCs were used as control. They were cultured for 4 days in adipogenic medium and transplanted under the dorsal skins of female Wistar rats after the hUMSCs had been labelled with chloromethylbenzamido-1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (CM-Dil). Macroscopical impression, fluorescence observation, histology and SEM were used for assessment after transplantation at 8 and 12 weeks. Macroscopically, newly formed adipose tissue was observed in the experimental group and control group after 8 and 12 weeks. Fluorescence observation supported that the formed adipose tissue originated from seeded hUMSCs rather than from possible infiltrating perivascular tissue. Oil red O staining of newly formed tissue showed that there was substantially more tissue regeneration in the experimental group than in the control group. SEM showed that experimental group cells had more fat-like cells, whose volume was larger than that of the control group, and degradation of the silk fibroin scaffold was greater under SEM observation. This study provides significant evidence that hUMSCs transfected by adenovirus vector have good compatibility with silk fibroin scaffold, and adenoviral transfection of the human insulin gene can be used for the construction of tissue-engineered adipose. Copyright © 2013 John Wiley & Sons, Ltd.

Rotary meat grinders with bone chip removal facilities are advanced meat mincing machinery, characterized by undesirable hard-particle separation from ground meat during grinding operations. The grinder plate with an involute spiral groove to facilitate removal of hard particles is developed. The perforated plate with bone chips removal facilities has a unique design including catcher groove, bone-collection chamber and bone-removal passage. Its 3D modeling in Pro/E software, machining process planning, milling path optimization, simulation based on MasterCAM and compiling post program were introduced and verified. The results indicated that adoption of CAD/CAM offers firms the potential to pursue new innovative strategies.

The service condition of plane thrust bearing of worm shaft in an oil screw press was analyzed. The fracture failure of the bearing rings was systematically investigated through physical-chemical test, trace inspection, fractographic appearance, and metallographic structure analysis. The results showed that a great amount of network surface cracks near bearing ring edge, some dot shaped internal oxidations and secondary crack initiation, higher hardness, as well as the network carbides and coarse quenching martensites led to the early brittle fracture of the bearing rings. The further improvements were normalizing and isothermal spheroidizing annealing can eliminate the network carbides and improve the microstructure in preheat treatment process, and quenching temperature and heating time can not be too high and long in final heat treatment. Hardness of the material is preferably 60-62 HRC.

The pressing chamber is the heart of the screw press, it forms the drainage barrel and has to contain the operating forces of the press. As press casing is an integral part of pressing chamber, the strength of the press casing ensures normal operation of the press. The mechanical models of pressing chamber of the ZX10 type press created in MATLAB 7.0 for linear programming, and the 3D model of the press casing created in UG NX4.0 software were imported into ANSYS 9.0 software and a linear static finite element analysis was performed. The visual deflection patterns the part experiences under "real world" loading conditions were obtained so as to complete the security check of strength.

An intelligent classification system of ceramic tiles is introduced in the light of the theory about multi-sensor information fusion. The system includes image acquisition, image processing and intelligent classification of ceramic tiles. The color features and shape features of tile image are synthetically processed using BP neural network. The topological structure of the neural network based on “681” structure is proposed in the system. The numerical calculation and simulation about classification of ceramic tiles is carried out based on MATLAB software. The results show this algorithm is fast and accurate, which can effectively accomplish the classification of comprehensive detection of ceramic tiles.

Rb+, Cs+ and other alkali metal ions in the Micro-channel Plate（MCP）channel, under the action of an electric field, leave out of the channel wall of MCP, and accelerate to input surface of channel along the opposite direction of the electric field to form ion feedback-induced noise. The feedback ions will cause great harms, it will bombard the cathode surface, resulting in decreased cathode sensitivity, reducing tube life, so you must take measures to reduce ion feedback-induced noise. This paper analyzes how to reduce ion feedback-induced noise from five aspects of the MCP materials, etching, annealing in hydrogen, high-temperature baking and electron scrubbing. Through the utilization of mixed alkali effect of suppressing mutual diffusion and decreasing internal network cavity to improve structure of MCP glass wall, the diffusion coefficient of each ion is reduced; the content of Al2O3 is reduced to reduce the Na+, K+ diffusion losses; etching process is optimized, except for the acid corrosion, the alkali corrosion, special acid etching and vacuum baking process are used; annealing in hydrogen technology is also optimized, the time of annealing in hydrogen was chosen on 270 ~ 350 minutes; and the vacuum baking and electron scrubbing are handled before manufacturing. By the above methods the ion feedback-induced noise is reduced.

We evaluated the use of a combination of human insulin gene-modified umbilical cord mesenchymal stromal cells (hUMSCs) with silk fibroin 3D scaffolds for adipose tissue engineering. In this study hUMSCs were isolated and cultured. HUMSCs infected with Ade-insulin-EGFP were seeded in fibroin 3D scaffolds with uniform 50-60 µm pore size. Silk fibroin scaffolds with untransfected hUMSCs were used as control. They were cultured for 4 days in adipogenic medium and transplanted under the dorsal skins of female Wistar rats after the hUMSCs had been labelled with chloromethylbenzamido-1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (CM-Dil). Macroscopical impression, fluorescence observation, histology and SEM were used for assessment after transplantation at 8 and 12 weeks. Macroscopically, newly formed adipose tissue was observed in the experimental group and control group after 8 and 12 weeks. Fluorescence observation supported that the formed adipose tissue originated from seeded hUMSCs rather than from possible infiltrating perivascular tissue. Oil red O staining of newly formed tissue showed that there was substantially more tissue regeneration in the experimental group than in the control group. SEM showed that experimental group cells had more fat-like cells, whose volume was larger than that of the control group, and degradation of the silk fibroin scaffold was greater under SEM observation. This study provides significant evidence that hUMSCs transfected by adenovirus vector have good compatibility with silk fibroin scaffold, and adenoviral transfection of the human insulin gene can be used for the construction of tissue-engineered adipose.

To investigate the effect of HMME-PDT on the proliferation and cell distribution of hypertrophic scar fibroblast (HSF).HSF were cultured and only 4-6th passages were used in this study. Argyrophilic protein in nucleolar organizer regions(AgNORs) were calculated by I. S% after argyrophilic staining. Flow cytometry was applied to analyze the cell cycle and proliferation index (PI).1) I. S% of HSF after HMME-PDT was reduced markedly. 2) HMME-PDT inhibited HSF entering S stage from G, stage, cell percentage in S stage was decreased to (11.2 +/- 2.3)%. 3) PI in HMME-PDT group was less than that in control group [(35.0 +/- 3.4)% vs (27.2 +/- 3.1)%, P0.05].HMME-PDT can inhibit proliferation of HSF, and chang cell distribution.