High myopia as a risk factor in primary open angle glaucoma

Glaucoma, one of the leading causes of irreversible blindness in the adult population worldwide, is a progressive optic neuropathy. Primary open angle glaucoma (POAG) is the most commonly reported type of glaucoma in population based prevalence studies worldwide. Elevated intraocular pressure is a well-known major risk factor for POAG. In addition, there is growing evidence that other risk factors like age, gender, race, refractive error, heredity and systemic factors may play a role in glaucoma pathogenesis. Many studies found that high myopia has been associated with POAG, however, direct and convincing evidences are still lacking. The aim of this review is to summarize the evidences implicating high myopia as a risk factor in the pathogenesis of POAG.

Development of a Novel Parallel-spool Pilot Operated High-pressure Solenoid Valve with High Flow Rate and High Speed

High-pressure solenoid valve with high flow rate and high speed is a key component in an underwater driving system.However,traditional single spool pilot operated valve cannot meet the demands of both high flow rate and high speed simultaneously.A new structure for a high pressure solenoid valve is needed to meet the demand of the underwater driving system.A novel parallel-spool pilot operated high-pressure solenoid valve is proposed to overcome the drawback of the current single spool design.Mathematical models of the opening process and flow rate of the valve are established.Opening response time of the valve is subdivided into 4 parts to analyze the properties of the opening response.Corresponding formulas to solve 4 parts of the response time are derived.Key factors that influence the opening response time are analyzed.According to the mathematical model of the valve,a simulation of the opening process is carried out by MATLAB.Parameters are chosen based on theoretical analysis to design the test prototype of the new type of valve.Opening response time of the designed valve is tested by verifying response of the current in the coil and displacement of the main valve spool.The experimental results are in agreement with the simulated results,therefore the validity of the theoretical analysis is verified.Experimental opening response time of the valve is 48.3 ms at working pressure of 10 MPa.The flow capacity test shows that the largest effective area is 126 mm2 and the largest air flow rate is 2320 L/s.According to the result of the load driving test,the valve can meet the demands of the driving system.The proposed valve with parallel spools provides a new method for the design of a high-pressure valve with fast response and large flow rate.

Digital image correlation based high-speed crack tip locatingmethod and its application

Based on a digital image correlation（DIC）method with the measurements of a high speed crack＇s displacement and strain fields,a technique to accurately and automatically locate its crack tip has been developed.The crack tip is identified by finding the abrupt jump on the opening（or dislocation）curve of a point on the trace of the crack propagation,while the opening is measured through a virtual extensometer technique and the abrupt jump is identified by finding the peak on the curve.The method was verified using a specially designed experiment and applied to measure the critical crack tip opening angle of a rock sample.Because the involvement of analytical models has been avoided and then the good performance could be ensured for low resolution speckle images,this technique is expected to be very useful in the quantitative study of high speed cracks in experiments using high speed cameras.

Does high intraocular pressure exclude an open globe injury?

Dear Sir,Ocular trauma is a topic of unresolved controversies and there are continuous controversial and debatable diagnostic and management strategies for open-globe injuries[1].Amongst many types of ocular trauma,the open globe injury is the most serious due to its very poor visual prognosis and young population of patients are mostly affected[2].The treatment outcome may be improved by prompt diagnosis,and immediate surgical repair performed to high standard[3].Amongst the other clinical signs the intraocular pressure(IOP)is found to be particularly reduced and conventionally this is considered as a very reliable indicator of occult globe

Single-shot incoherent optical processing of microwave signals： opening the path to low cost high performance analog photonics

Incoherent optical processing of microwave signals,where low-coherence broadband light sources are employed instead of costly mode locked lasers,has attracted great interest thanks to its wide applications in microwave photonics filtering[1–3],arbitrary generation[4–6]and analog to digital conversion[7]。

Effect of high myopia on 24-hour intraocular pressure in patients with primary open-angle glaucoma

Background As intraocular pressure （lOP） and lOP fluctuation are known risk factors for glaucoma, it is important to understand the effects of high myopia on these ocular parameters. The aim of this study was to investigate if primary open-angle glaucoma （POAG） patients with high myopia exhibit higher lOP and greater lOP fluctuations at resting conditions over 24 hours. Methods We designed a prospective control clinical study. Eighty-two eyes of 82 high-tension Chinese POAG patients only on prostaglandin analogue locally were divided into 3 groups according to various myopic grades （〈-6.0 D, n=27 and between -0.76 and -5.99 D, n=33） or without myopia （-0.75 to 0.75 D, n=22）. Single time lOP at 10 am, mean corrected 24-hour lOP, mean corrected night lOP, 24-hour lOP fluctuation and lOPs of 10 am, 2 pm, 6 pm, 10 pm, 2 am, 6 am and 8 am were measured. Results The lOP was higher in POAG patients with high myopia over those POAG alone in three ways： the elevated lOP value was 0.65 mmHg measured in single time lOP at 10 am, 0.84 mmHg in mean corrected 24-hour lOP, 0.97 mmHg in mean corrected night lOP. The 24-hour lOP fluctuation was lower in the two myopia groups than in non-myopia group. Further, using repeated measurement analysis of variance, there was no statistical significance among groups regarding the lOPs at the seven time points （P=0.77） and there was no interaction between groups and time points （P=0.71）, but the difference of lOPs at the seven time points in same group was statistically significant （P=0.01）. Conclusion High-tension POAG patients with high myopia, even on pharmacological glaucoma therapy, still have hinhe.r IC）P. h^Jt 24-hnur IC）P fluc.tuatinn at re.qtina ~.nnditinn.q wA.q InwAr in th~..~, n^ti~.nt.q

A-π-D-π-A Type Small Molecules Using Ethynylene Linkages for Organic Solar Cells with High Open-circuit Voltages

Introducing ethynylene linkages in a conjugated molecule can deepen the HOMO level, decrease the steric con- straints and better delocalize the n electrons and so on, which are beneficial for organic solar cells. Furthermore, the typical method of introducing acetylene linkages by Sonogashira reactions can avoid the usage of toxic stannyl in- termediates and potentially dangerous lithiation reactions. In this study, two simple small molecules BEDPP and NEDPP are designed and synthesized, in which two diketopyrrolopyrrole units are symmetrically connected to benzene and naphthalene cores, respectively, via acetylene linkages. And the BHJ （Bulk Heterojunction） solar cells based on BEDPP and NEDPP without using solvent additive and without any post-treatment for the active layers provide us power conversion efficieneies of 1.48% and 2.31% with remarkably high open circuit voltages up to 0.90 and 0.98 V, respectively.