Effect of low-degree astigmatism on the objective visual quality

AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corrected-to-normal vision.The cylindrical lenses(0,0.5,0.75,1.0,and 1.25 D)were placed at the axial direction(180°,45°,90°,and 135°)in front of the eyes with the best correction to form 16 types of regular low-degree astigmatism.OQAS was used to detect the objective visual quality,recorded as the objective scattering index(OSI),OQAS values at contrasts of 100%,20%,and 9%predictive visual acuity(OV100%,OV20%,and OV9%),modulation transfer function cut-off(MTFcut-off)and Strehl ratio(SR).The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality parameters.RESULTS:Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were observed.The increase of OSI per degree of astigmatism at 180°,45°,90°,and 135°axis were 0.38(95%CI:0.35,0.42),0.50(95%CI:0.46,0.53),0.49(95%CI:0.45,0.54)and 0.37(95%CI:0.34,0.41),respectively.The decrease of MTFcut-off per degree of astigmatism at 180°,45°,90°,and 135°axis were-10.30(95%CI:-11.43,-9.16),-12.73(95%CI:-13.62,-11.86),-12.75(95%CI:-13.79,-11.70),and-9.97(95%CI:-10.92,-9.03),respectively.At the same astigmatism degree,OSI at 45°and 90°axis were higher than that at 0°and 135°axis,while MTFcut-off were lower.CONCLUSION:Low astigmatism of only 0.50 D can significantly reduce the objective visual quality.

Long-term observation on safety and visual quality of implantable collamer lens V4c implantation for myopia correction:a 5-year follow-up

AIM:To elucidate the safety and visual quality of implantable collamer lens with central hole(ICL V4c)implantation for correcting moderate and high myopia for at least 5y.METHODS:This retrospective study was conducted on 58 patients(114 eyes)who were followed up for at least 5y after ICL V4c implantation.The observation was done before and on 1d,1mo,1 and 5y or more after the surgical procedure.The visual acuity,subjective refraction,intraocular pressure,vault,axial length,central hole position,pupil diameter,visual quality,and adverse events were analyzed.The visual quality includes aberration,the modulation transfer function cutoff frequency(MTF cutoff),objective scattering index(OSI),Stroller's ratio(SR),and visual quality questionnaire.RESULTS:The average follow-up period was 69.25±3.80mo(range 60–82mo)and the preoperative spherical equivalent(SE)was-8.66±1.97 D.At 5y after operation,the safety index was 1.01±0.02 and the efficacy index was 0.99±0.42 and SE was-0.65±0.63 D.The 59.6%of the eyes achieved an uncorrected distance visual acuity of 20/20,76.3%of the eyes had SE within±1.0 D at the last visit.The axial length increased by 0.29±0.71 mm 5y after the surgery(t=-3.843,P<0.001).The mean vault at the last follow-up was 510.59±245.61μm.The central hole was on the temporal side in 80 eyes(84.2%).The visual quality questionnaire showed that 98.2%patients were satisfied with the surgical procedure.Adverse events occurred in 4 eyes(3.5%),including the posttraumatic toric ICL rotation(2 eyes),iris incarceration(1 eye),and posttraumatic ICL displacement(1 eye)at the last follow-up.CONCLUSION:Long-term ICL V4c implantation is safe,effective,and stable for correcting moderate and to high myopia,and the visual quality with patients is excellent and satisfactory,but the progression of axial length still needs attention after surgery.

A 3-month comparison study of subjective and objective visual quality of small incision lenticule extraction and transepithelial photorefractive keratectomy in patients with low and moderate myopia

AIM:To compare the subjective and objective visual quality between small incision lenticule extraction(SMILE)and transepithelial photorefractive keratectomy(t PRK)in patients with low and moderate myopia.METHODS:Patients undertaking SMILE or t PRK for the correction of low and moderate myopia were consecutively recruited in this prospective cohort study with a 3-month follow-up period.Objective evaluation[visual acuity test,manifest refraction,wavefront aberrations,the total cut-off value of the total modulation transfer function(MTFcut-off),and Strehl ratio(SR)]and subjective evaluation of visual quality(quality-of-life questionnaire)were conducted before surgery and at days 1,7,30,and 90 after surgery.RESULTS:A total of 47 patients(94 eyes)with SMILE and 22 patients(22 eyes)with t PRK were enrolled.The uncorrected visual acuity(UCVA)was better in SMILE patients on day 7 after surgery(1.13±0.13 vs 0.99±0.17,t=4.85,P<0.001)but was comparable at days 30 and 90.At day 90,the SMILE group had a lower spherical equivalent(SE)than the t PRK group(0.04±0.31 vs 0.19±0.43,t=2.08,P=0.042).Total higher order aberrations(HOAs)were induced in both surgical types,which were more evident in the t PRK group with 3-mm pupil diameter(0.16±0.07 vs0.11±0.05,t=4.27,P<0.001)and 5-mm pupil diameter(0.39±0.17 vs 0.36±0.11,t=2.33,P=0.022).The MTFcut-offand SR showed a trend of improvement in both SMILE and t PRK patients but were statistically better in the SMILE group with both pupil diameters.There was a significant improvement of contrast sensitivity(CS)over baseline levels at the spatial frequency of 18 cycles/degree(c/d)in the SMILE group(F=2.72,P=0.033)and at 3 c/d(F=3.03,P=0.031),12 c/d(F=3.72,P=0.013),and 18 c/d(F=4.62,P=0.004)in the t PRK group.The subjective quality of life questionnaire showed a steady improvement in the SMILE group(F=8.31,P<0.001)but not the t PRK group.CONCLUSION:SMILE and t PRK are both safe and effective ways to correct low and moderate myopia.A generally better and quicker recovery of visual quality favors the application of SMILE in qualified patients.

Application of Eye Movement Analysis in Landscape Visual Quality Evaluation

The existing methods of landscape visual quality evaluation is mostly based on people's subjective feelings,and the objectivity and scientificity of evaluation results are insufficient.As an important means of experimental psychology,eye movement technology can show great advantages and potential in landscape visual quality evaluation.On the basis of combing and summarizing the relevant literature,based on the explanation of the technical principle of eye movement analysis,the application field,research content,technical methods and other aspects of eye movement analysis were reviewed.The application prospect of eye movement technology in landscape visual quality evaluation was explored to provide theoretical reference for the in-depth evaluation and research of landscape visual quality evaluation theory.

Comparison of visual quality after implantation of Al-UV and SN60WF aspheric intraocular lens

AIM:To compare the visual performance of pseudophakic eyes implanted with Al-UV and SN60WF aspheric intraocular lens(IOL),and to investigate the correlations between visual quality parameters and pupil size.METHODS:This prospective comparative study included 105 eyes of 90 patients with age-related cataract who underwent uneventful phacoemulsification.The subjects were divided into two groups according to the implanted IOL type.Three months postoperatively,visual acuity and contrast sensitivity were measured,wave-front aberrations were assessed using a KR-IW aberrometer(Topcon),and objective optical quality parameters were performed using an optical quality analysis system-OQAS Il(Visiometrics).Independent sample Mest and Spearman correlation analysis were used for data analysis.RESULTS:There were no significant differences found in visual acuity,contrast sensitivity and visual quality parameters between the two groups(P>0.05).The measured intraocular spherical aberration(SA)in Al-UV IOL eyes of-0.19±0.05 pm was close to the designed SA value of-0.20 pm.The modulation transfer function cutoff,Strehl ratio and OQAS values were negatively correlated with pupil size in both groups(P<0.01).CONCLUSION:The subjective and objective visual quality in pseudophakic eyes with A1-UV and SN60WF IOLs are comparable.For aspheric IOL eyes,visual quality decreases with increasing pupil size.

Visual quality assessment after presbyopic laser in-situ keratomileusis

AIM： To assess visual quality after presbyopia correction using an aspheric ablation profile and a micro-monovision protocol. METHODS： This is a retrospective interventional study. Fifty-four eyes of 27 patients （mean age, 50.2±7.5y） who underwent presbyopia correction with an aspheric micro-monovision protocol were enrolled. The values of modulation transfer function （MTF） cutoff frequency, Strehl ratio, objective scattering index （OSI） and accommodation range were quantitatively assessed using the HD analyzer. Preoperative and postoperative contrast sensitivity （CS） at far （2.5 m） and near （40 cm） distance and higher-order aberrations （HOAs） were analyzed. Subjective visual satisfaction was evaluated by self-reported questionnaire regarding optical visual symptoms. RESULTS： One year after presbyopia correction, no significant differences were found in the MTF cutoff frequency, Strehl ratio and OSI, however, the lID analyzer accommodation range significantly differed postoperatively （P=0.004）. Postoperative CS at 12 and 18 cpd at near showed statistically significant improvement （P=0.020 and 0.008, respectively）. Visual performance by self-reported questionnaire revealed satisfactory results in terms of subjective visual quality improvement. CONCLUSION： Objective optical quality parameters show good visual outcomes. Subjective visual quality assessed by self-reported questionnaire in the presbyopia correction group show satisfactory results.

Comparative study of objective visual quality between FS-LASIK and SMART in myopia

AIM:To compare the changes in the objective visual quality of patients with low and moderate myopia postoperatively after transepithelial photorefractive keratectomy using the smart pulse technology(SMART)and femtosecond laser in situ keratomileusis(FS-LASIK).METHODS:Corneal higher-order aberrations(HOAs),horizontal coma,vertical coma and spherical aberration were measured using Pentacam,and cutoff for modulation transfer function(MTF cutoff),objective scatter index(OSI)and Strehl ratio(SR)was measured using an optical quality analysis system(OQAS-II),before and after operation at 1,3,and 6 mo,and data were analyzed by repeated measurement two-way analysis of variance.RESULTS:The difference in uncorrected distance visual acuity between SMART and FS-LASIK was statistically significant only 1 wk postoperatively.Approximately 86.36%and 80.69%of patients with spherical equivalent(SE)in±0.50 D were observed in the SMART and FS-LASIK groups,respectively.No significant difference was observed in SE between the two groups(P=0.509).The HOAs increased postoperatively compared with those before surgery in both groups(P<0.05).No significant difference in HOA,corneal horizontal coma,spherical aberration,ΔHOA,Δhorizontal coma,andΔspherical aberration were observed between the two group(P>0.05).Corneal vertical coma andΔcorneal vertical coma in the FS-LASIK group were higher than those in the SMART group(P<0.05).The OSI of both groups at 1 mo after surgery was higher than that before surgery(P<0.05).At 3 and 6 mo postoperatively,the OSI in the FS-LASIK group was slightly higher than that in the SMART group(P=0.040 and 0.047,respectively).At 6 mo after surgery,the MTF cutoff was statistically significant different between the two groups(P=0.026).No significant difference in SR between the FS-LASIK and SMART groups was observed at 1,3,and 6 mo postoperatively(P>0.05).CONCLUSION:The HOAs increase and visual quality is delayed in both groups postoperatively,and the long-term objective visual quality after SMART is slightly better than that after FS-LASIK.

Objective visual quality one year after toric IOL implantation for correction of moderate and high corneal astigmatism

AIM:To compare the objective visual quality after implantation of a toric intraocular lens(IOL)in order to correct moderate or high corneal astigmatism at the one year postoperative follow-up.METHODS:From December 2017 to June 2018,66 patients(90 eyes)with simple age-related cataract with regular corneal astigmatism greater than 1.5 D were enrolled in this prospective self-control study.The patients were implanted with Proming?toric IOL(model:AT3 BH-AT6 BH).The subjects were divided into moderate astigmatism group(46 eyes,1.5-2.5 D)and high astigmatism group(44 eyes,>2.5 D).The uncorrected distance visual acuity,residual astigmatism and axial position of IOL were observed before operation,3,6 mo and 1 y after operation.Modulation transfer function cutoff(MTF cutoff),Strehl ratio(SR),object scatter index(OSI)were observed by OQAS II to evaluate the objective visual quality of patients.RESULTS:There was no significant difference in UCVA,residual astigmatism,axial deviation,MTF cutoff,SR and OSI between moderate and high astigmatism group(all P>0.05).After 3 mo,UCVA,MTF cutoff and SR were significantly increased(all P<0.05),residual astigmatism and OSI were significantly decreased(all P<0.05).After 3 mo,all the indexes remained stable.CONCLUSION:Proming toric IOL can effectively treat age-related cataract patients with moderate-to-high regular corneal astigmatism,correcting corneal astigmatism,improving UCVA,ensuring long-term stability in the capsule,and providing patients with better visual quality.

Effects of upper lid blepharoplasty on visual quality in patients with lash ptosis and dermatochalasis

AIM：To assess the effects of upper lid blepharoplasty on visual quality.METHODS：Seventy-three eyelids of 39 patients were subjected to upper lid blepharoplasty.Pre- and postoperative contrast sensitivity,visual acuity,vertical palpebral aperture and the degree of lash ptosis were measured.RESULTS：The mean log contrast sensitivities under photopic（P =0.017） and scotopic conditions（P =0.009）were improved after surgery,and these differences were significant.The degree of lash ptosis was also decreased after blepharoplasty（P〈0.001）.CONCLUSION：In our study,a significant increase in contrast sensitivity was found after surgery.These results suggest that upper lid blepharoplasty can be helpful for improving visual quality.

Comparative analysis of visual quality between unilateral implantation of a trifocal intraocular lens and a rotationally asymmetric refractive multifocal intraocular lens

·AIM:To compare visual quality after unilateral cataract surgery with implantation of trifocal intraocular lens(IOL)and asymmetric refractive multifocal IOL.·METHODS:The prospective nonrandom,comparative study consisted of 60 eyes of 60 patients suffering unilateral cataract surgery with implantation of two different IOLs:AT LISA tri 839 MP(30 eyes;Carl Zeiss Meditec,Germany)and LS-313 MF30(30 eyes;Oculentis GmbH,Germany).Visual acuity,refractive outcome,contrast sensitivity,defocus curves,quality of vision,and optical phenomena were evaluated at3 mo postoperatively.·RESULTS:There were no statistical differences between groups in uncorrected distance visual acuity(P=0.13)and uncorrected near visual acuity(P=0.54).In contrast,uncorrected intermediate visual acuity was better in trifocal group compared to the refractive multifocal group(P=0.02).No significant statistical between-group difference was detected in cylinder(P=0.43).Compared to trifocal group,spherical refraction and spherical equivalent in refractive multi focal group were more myopic(P<0.01).Under photopic conditions,no significant statistical differences were found between groups in contrast sensitivity at 3 and 6 cycles per degree(cpd).The refractive multifocal group performed better at 12 and 18 cpd than the trifocal group(P=0.01,P=0.034,respectively).The questionnaires of quality of vision and optical phenomena showed no differences between groups.·CONCLUSION:Trifocal IOL is superior to refractive multifocal IOL in intermediate visual acuity.Rotationally asymmetric refractive multifocal IOL is more myopic in automated refraction and significantly better for the photopic contrast sensitivity at high frequency.

High Visual Quality Image Steganography Based on Encoder-Decoder Model

Nowadays,with the popularization of network technology,more and more people are concerned about the problem of cyber security.Steganography,a technique dedicated to protecting peoples’private data,has become a hot topic in the research field.However,there are still some problems in the current research.For example,the visual quality of dense images generated by some steganographic algorithms is not good enough;the security of the steganographic algorithm is not high enough,which makes it easy to be attacked by others.In this paper,we propose a novel high visual quality image steganographic neural network based on encoder-decoder model to solve these problems mentioned above.Firstly,we design a novel encoder module by applying the structure of U-Net++,which aims to achieve higher visual quality.Then,the steganalyzer is heuristically added into the model in order to improve the security.Finally,the network model is used to generate the stego images via adversarial training.Experimental results demonstrate that our proposed scheme can achieve better performance in terms of visual quality and security.

Exploring visual quality of multidimensional time series projections

Dimensionality reduction is often used to project time series data from multidimensional to two-dimensional space to generate visual representations of the temporal evolution.In this context,we address the problem of multidimensional time series visualization by presenting a new method to show and handle projection errors introduced by dimensionality reduction techniques on multidimensional temporal data.For visualization,subsequent time instances are rendered as dots that are connected by lines or curves to indicate the temporal dependencies.However,inevitable projection artifacts may lead to poor visualization quality and misinterpretation of the temporal information.Wrongly projected data points,inaccurate variations in the distances between projected time instances,and intersections of connecting lines could lead to wrong assumptions about the original data.We adapt local and global quality metrics to measure the visual quality along the projected time series,and we introduce a model to assess the projection error at intersecting lines.These serve as a basis for our new uncertainty visualization techniques that use different visual encodings and interactions to indicate,communicate,and work with the visualization uncertainty from projection errors and artifacts along the timeline of data points,their connections,and intersections.Our approach is agnostic to the projection method and works for linear and non-linear dimensionality reduction methods alike.

Effect of capsule treatment on visual acuity and quality after phacoemulsification lens implantation in myopic patients with cataract

BACKGROUND Cataracts pose a significant clinical burden due to their complex pathogenesis.In recent years,an increase in cataracts coexisting with myopia has heightened the incidence of retinopathy and posterior vitreous detachment.Additionally,symptoms of ocular axis elongation,lens nucleus hardening,and vitreous liquefaction have become more prevalent.While conventional extracapsular cataract extraction is commonly employed,it often yields suboptimal visual outcomes.Subsequent advancements in cataract phacoemulsification and lens implantation surgeries have gained widespread acceptance for their ability to improve refraction and significantly improve uncorrected visual acuity.AIM To investigate the effect of capsular treatment after phacoemulsification lens implantation in myopic patients with cataract.METHODS We selected 110 patients(with 134 eyes)with myopia and cataracts treated.These patients were categorized into two groups:an observation group(57 patients with 70 eyes)and a control group(53 patients with 64 eyes).The control group underwent cataract phacoemulsification and lens implantation,while the observation group received a refined capsular treatment based on the control group’s procedure.We assessed the differences in visual acuity and quality between the two groups before and after surgery.RESULTS At six months post-operation,the observation group exhibited significantly improved far vision,intermediate vision,near vision,lower objective scattering index,higher Modulation transfer function cut-off frequency,and overall vision metrics at different contrast levels(100%,20%and 9%)compared to the control group(P<0.05).The total score of the National Eye Institute Visual Function Questionnaire in the observation group at 6 months after operation was significantly higher than that in the control group(P<0.05).No significant difference in the incidence of adverse reactions was observed between the observation group and control group(P>0.05).CONCLUSION Capsular treatment demonstrates efficacy in improving visual acuity and quality after phacoemulsification lens implantation in myopic patients with cataracts,warranting its clinical application.

Visual quality of juvenile myopes wearing multifocal soft contact lenses

Background:It is unclear whether multifocal soft contact lenses(MFSCLs)affect visual quality when they are used for myopia control in juvenile myopes.The aim of this study was,therefore,to investigate the effect of MFSCLs on visual quality among juvenile myopia subjects.Methods:In a prospective,intervention study,thirty-three juvenile myopes were enrolled.Visual perception was assessed by a quality of vision(QoV)questionnaire with spectacles at baseline and after 1 month of MFSCL wear.At the one-month visit,the high(96%)contrast distance visual acuity(distance HCVA)and low(10%)contrast distance visual acuity(distance LCVA)were measured with single vision spectacle lenses,single vision soft contact lenses(SVSCLs)and MFSCLs in a random order.Wavefront aberrations were measured with SVSCLs,with MFSCLs,and without any correction.Results:Neither distance HCVA(p>0.05)nor distance LCVA(p>0.05)revealed any significant difference between MFSCLs,SVSCLs and single vision spectacle lenses.The overall score(the sum of ten symptoms)of the QoV questionnaire did not show a statistically significant difference between spectacles at baseline and after 1 month of MFSCL wear(p=0.357).The results showed that the frequency(p<0.001),severity(p=0.001)and bothersome degree(p=0.016)of halos were significantly worse when wearing MFSCLs than when wearing single vision spectacle lenses.In contrast,the bothersome degree caused by focusing difficulty(p=0.046)and the frequency of difficulty in judging distance or depth perception(p=0.046)were better when wearing MFSCLs than when wearing single vision spectacle lenses.Compared with the naked eye,MFSCLs increased the total aberrations(p<0.001),higher-order aberrations(p<0.001),trefoil(p=0.023),coma aberrations(p<0.001)and spherical aberrations(SA)(p<0.001).Compared with the SVSCLs,MFSCLs increased the total aberrations(p<0.001),higher-order aberrations(p<0.001),coma aberrations(p<0.001)and SA(p<0.001).The direction of SA was more positive(p<0.001)with the MFSCLs and more negative(p=0.001)with the SVSCLs compared with the naked eye.Conclusions:Wearing MFSCLs can provide satisfactory corrected visual acuity(both distance HCVA and distance LCVA).Although the lenses increased the aberrations,such as total aberrations and higher-order aberrations,there were few adverse effects on the distance HCVA,distance LCVA and visual perception after 1 month of MFSCL use.

Visual quality of juvenile myopes wearing multifocal soft contact lenses

Background:It is unclear whether multifocal soft contact lenses(MFSCLs)affect visual quality when they are used for myopia control in juvenile myopes.The aim of this study was,therefore,to investigate the effect of MFSCLs on visual quality among juvenile myopia subjects.Methods:In a prospective,intervention study,33 juvenile myopes were enrolled.Visual perception was assessed by a quality of vision(QoV)questionnaire with spectacles at baseline and after one month of MFSCL wear.At the one month visit,the high(96%)contrast distance visual acuity(distance HCVA)and low(10%)contrast distance visual acuity(distance LCVA)were measured with single-vision spectacle lenses,single-vision soft contact lenses(SVSCLs)and MFSCLs in a random order.Wavefront aberrations Were measured with SVSCLs,MFSCLs and,without anycorrection.Results:Neither distance HCVA(P>0.05)nor distance LCVA(P>0.05)revealed any significant difference between MFSCLs,SVSCLs and single-vision spectacle lenses.The overall score(the sum of ten symptoms)of the QoV questionnaire did not show a statistically significant difference between spectacles at baseline and after one month of MFSCL wear(P=0.357).The results showed that the frequency(P<0.001),severity(P=0.001)and bothersome degree(P=0.016)of halos were significantly worse when wearing MFSCLs than when wearing single-vision spectacle lenses.In contrast,the bothersome degree caused by focusing difficulty(P=0.046)and the frequency of difficulty in judging distance or depth perception(P=0.046)were better when wearing MFSCLs than when wearing single-vision spectacle lenses.Compared with the naked eye,MFSCLs increased the total aberrations(P<0.001),higher-order aberrations(P<0.001),trefoil(P=0.023),coma aberrations(P<0.001)and spherical aberrations(SA)(P<0.001).Compared with the SVSCLs,MFSCLs increased the total aberrations(P<0.001),higher-order aberrations(P<0.001),coma aberrations(P<0.001)and SA(P<0.001).The direction of SA was more positive(P<0.001)with the MFSCLs and more negative(P=0.001)with the SVSCLs compared with the naked eye.Conclusions:Wearing MFSCLs can provide satisfactory corrected visual acuity(both distance HCVA and distance LCVA).Although the lenses increased the aberrations,such as total aberrations and higher-order aberrations,there were few adverse effects on the distance HCVA,distance LCVA and visual perception after one month of MFSCL Wear.

Exploring the efficiency of image metric for assessing the visual quality of 3D mesh model

Recent developments in 3D graphics technology have led to extensive processes on 3D meshes(e.g.,compression,simplification,transmission and watermarking),these processes unavoidably cause the visual perceptual degradation of the 3D objects.The existing mesh visual quality evaluation metrics either require topology constrain or fail to reflect the perceived visual quality.Meanwhile,for the 3D objects that are observed on 2D screens by the users,it is reasonable to apply image metric to assess the distortion caused by mesh simplification.We attempt to explore the efficiency of image metric for assessing the visual fidelity of the simplified 3D model in this paper.For this purpose,several latest and most effective image metrics,2D snapshots,number and pooling algorithms are involved in our study,and finally tested on the IEETA simplification database.The statistical data allow the researcher to select the optimal parameter for this image-based mesh visual quality assessment and provide a new perspective for the design and performance assessment of mesh simplification algorithms.

The Use of Self-cleaning Materials and Study Their Impact on the Quality of the Visual Appearance of Large Industrial Cities

One of the capabilities of the architecture is to respond to growing and,in some cases,varied needs of users.However,architecture and construction industry,in comparison with other sciences,have been very slow and inadequate to implement this technology despite very suitable ground for improvement.At the moment,one of the most essential discussions in this field is how to achieve qualitative understanding of construction materials.Accordingly,one of the key sections of a construction which plays a significant role in optimizing performance is shell of the building.In this article,in addition to the utilization technique of selfcleaning materials in construction industry which will result in embellishment of urban design,an attempt has also been made to present a suitable model on how to utilize these materials in order to improve the visual appearance quality of megalopolises.The technology of self-cleaning surfaces in order to increase durability and reduce costs and required time for equipment maintenance has currently become the focal point in construction industry.Now providing one answer to the question of whether will selfcleaning,purifying facades change the future of urban architecture?The main panorama of this research is to find and establish a dynamic and sustainable balance in embellishment of urban design.The necessity of research in this field as well as finding the best and most practical solution seem.To achieve all this,an analytical and descriptive research has been utilized,data has been collected by various books and national and international websites.

A Cover-Independent Deep Image Hiding Method Based on Domain Attention Mechanism

Recently,deep image-hiding techniques have attracted considerable attention in covert communication and high-capacity information hiding.However,these approaches have some limitations.For example,a cover image lacks self-adaptability,information leakage,or weak concealment.To address these issues,this study proposes a universal and adaptable image-hiding method.First,a domain attention mechanism is designed by combining the Atrous convolution,which makes better use of the relationship between the secret image domain and the cover image domain.Second,to improve perceived human similarity,perceptual loss is incorporated into the training process.The experimental results are promising,with the proposed method achieving an average pixel discrepancy(APD)of 1.83 and a peak signal-to-noise ratio(PSNR)value of 40.72 dB between the cover and stego images,indicative of its high-quality output.Furthermore,the structural similarity index measure(SSIM)reaches 0.985 while the learned perceptual image patch similarity(LPIPS)remarkably registers at 0.0001.Moreover,self-testing and cross-experiments demonstrate the model’s adaptability and generalization in unknown hidden spaces,making it suitable for diverse computer vision tasks.

Effectivity and safety of trifocal intraocular lenses and capsular tension rings implantation for cataract patients with axial high myopia

●AIM:To assess effectivity and safety of trifocal intraocular lenses(IOLs)and capsular tension rings in treating cataract patients with axial high myopia.●METHODS:A prospective nonrandomized controlled clinical trial was conducted.Totally 98 eyes(74 patients)who underwent femtosecond laser-assisted cataract surgery(FLACS)with trifocal IOLs were enrolled in the study and followed up for 2y after surgery:46 eyes(33 patients)with capsular tension ring implantation in the long axial lengths(AL)group(26<AL<29 mm)and 52 eyes(41 patients)in the normal AL group(22<AL<24.5 mm).Postoperative outcomes about effectivity and safety,including the subjective and objective visual quality,and postoperative complications were assessed.●RESULTS:Uncorrected distance visual acuity at 5 m and uncorrected intermediate visual acuity at 60 and 80 cm in the long AL group were significantly worse than those in the normal AL group at 3mo postoperatively(P<0.05).The differences in reading speed,spectacle independence and potential visual complaints between the two groups were not statistically significant(P>0.05).The dysfunctional lens index and total modulation transfer function(MTF)average height were similar between the two groups.The postoperative internal coma aberrations in the axial high myopia eyes were significantly higher than that in the normal AL group(P<0.05).The total satisfaction score in the long AL group(91.32±2.76)was slightly higher than that in the normal AL group(90.36±3.47),but there was no difference(P=0.136).A statistically negative correlation was found between corrected distance visual acuity(CDVA)and dysfunctional lens index(r=-0.382,P=0.009),and between CDVA and the total MTF average height(r=-0.374,P=0.01).But there was no significant correlation between CDVA and total satisfaction score(r=0.059,P=0.696).Postoperative complications mainly presented as posterior capsular opacity(PCO),retinal detachment and cystoid macular edema.There was no difference in the incidence of fundus disease(6.5%vs 3.8%,P=0.663)or PCO(17.4%vs 7.7%,P=0.217)between the two groups at two years.●CONCLUSION:The utilization of trifocal IOL and capsular tension ring implantation is beneficial for cataract patients with axial high myopia undergoing FLACS.This approach not only ensures excellent subjective feelings and objective visual quality,but also does not increase the incidence of postoperative complications.

Correlation between visual function and refractive,topographic, pachymetric and aberrometric data in eyes with keratoconus

AIMTo analyze the relationship between two visual functions and refractive, topographic, pachymetric and aberrometric indicators in eyes with keratoconus.METHODSCorrected distance visual acuity (CDVA), and letter contrast sensitivity (CS) were correlated with refraction, corneal topography, pachymetry, and total corneal wavefront data prospectively in 71 eyes with keratoconus. The topographic indices assessed were simulated keratometry for the flattest and steepest meridians (SimK1 and SimK2), posterior steeper K (Ks), elevation value in best-fit sphere (BFS) maps, squared eccentricity (Є2), aspheric asymmetric index (AAI), pachymetry, thickness progression index (TPI), the amount of pachymetric decentralization (APD), and GalileiTM-keratoconus indices.RESULTSThe mean CDVA (expressed as logMAR) were 0.25±0.21. The mean CS was 1.25±0.46. The spherical refraction correlated well with CDVA (r=-0.526, P<0.001). From topographic indices, SRI correlated with CS (r=-0.695), and IAI with CS (r=-0.672) (P<0.001 for all). Root mean square (RMS) was 4.3±1.81 µm, spherical aberration (SA) was -0.4±0.67 µm, vertical and horizontal coma were -2.1±1.47 and -0.4±0.72 µm. All wavefront data (except horizontal coma), AAI, Є2 and maximum BFS correlated significantly with the visual function (P≤0.001 for all).CONCLUSIONIn this study, CS is more affected than CDVA as a visual function. The quantity and quality of vision is significantly correlated with well-known and new topographic indices. There is not a significant correlation between visual function and pachymetric parameters. The significantly correlated indices can be used in staging keratoconus and to follow the outcome of a treatment.