AIM:To evaluate the effectiveness and safety of intravitreal ranibizumab(IVR)for diabetic macular edema(DME)in vitrectomized versus non-vitrectomized eyes.METHODS:The PubMed,EMBASE,Web of Science,Cochrane,EBSCO were c...AIM:To evaluate the effectiveness and safety of intravitreal ranibizumab(IVR)for diabetic macular edema(DME)in vitrectomized versus non-vitrectomized eyes.METHODS:The PubMed,EMBASE,Web of Science,Cochrane,EBSCO were comprehensively searched for studies comparing vitrectomized and non-vitrectomized eyes with DME.Clinical outcomes of best-corrected visual acuity(BCVA),central macular thickness(CMT),the mean number of intravitreal injection and adverse events were extracted and analyzed.RESULTS:Six studies involving 641 eyes were included.Final visual gain significantly improved and CMT significantly reduced in vitrectomized eyes at 6mo and 12mo visits(P<0.05).Although the mean reduction in CMT among non-vitrectomized eyes was significantly greater than in vitrectomized eyes at the 6mo[mean difference(MD)=53.57,95%confidence interval(CI):28.03 to 78.72,P<0.0001]and 12mo(MD=49.65,95%CI:19.58 to 79.72,P=0.01),no significant difference was detected in improvement in BCVA at either 6mo(MD=0.05,95%CI:-0.02 to 0.13,P=0.14)or 12mo(MD=0.03,95%CI:-0.04 to 0.09,P=0.43).Injection number of ranibizumab in non-vitrectomized eyes was significantly less than that in vitrectomized eyes during 6-month period(MD=0.60,95%CI:0.16 to 1.04,P=0.008),while there was no statistically significant difference between the two groups during 12mo of follow-up.CONCLUSION:Evidence from current study suggests that IVR was useful for both vitrectomized group and nonvitrectomized group with DME.Although less reduction in macular thickness is found in vitrectomized group,visual improvement between two groups is similar.展开更多
This narrative review aimed to have an algorithmic approach to microphthalmos by a systematic search.The definition can be related to a number of special phenotypes.In the more challenging cases of complex microphthal...This narrative review aimed to have an algorithmic approach to microphthalmos by a systematic search.The definition can be related to a number of special phenotypes.In the more challenging cases of complex microphthalmos,relative anterior microphthalmos,and nanophthalmos,the surgeon can approach these cases more safely if they have a deep understanding of the anatomical variations and ideal formulae for intraocular lens computation and knows how to avoid intra-and post-operative complications.In this article,we review the criteria by which we recognize and describe pre-,intra-,and post-operative considerations,as well as discuss the ideal intraocular lenses for microphthalmos,given the intricate varieties of small eye phenotypes.展开更多
AIM:To investigate the influence of ophthalmic viscoelastic devices(OVDs)and different surgical approaches on the intraocular pressure(IOP)before and after creation of the curvilinear circular capsulorhexis(CCC)as a m...AIM:To investigate the influence of ophthalmic viscoelastic devices(OVDs)and different surgical approaches on the intraocular pressure(IOP)before and after creation of the curvilinear circular capsulorhexis(CCC)as a measure for anterior chamber stability during this maneuver.METHODS:Prospective experimental WetLab study carried out on enucleated porcine eyes.IOP was measured before and after CCC with the iCare Rebound tonometer(iCare ic200;iCare Finland Oy,Vantaa,Finland).The OVDs used were a cohesive one[Z-Hyalin,Carl Zeiss Meditec AG,Germany;hyaluronic acid(HA)]and a dispersive[Z-Celcoat,Carl Zeiss Meditec AG,Germany;hydroxy propylmethylcellulosis(HPMC)].The CCC was created using Utrata forceps or 23 g microforceps in different combinations with the OVDs.RESULTS:Using the Utrata forceps the IOP dropped from 63.65±6.44 to 11.25±3.63 mm Hg during the CCC.The use of different OVDs made no difference.Using the 23 g microforceps the IOP dropped from 65.35±8.15 to 36.55±6.09 mm Hg.The difference between IOP drop using either Utrata forceps or 23 g microforceps was highly significant regardless of the OVD used.CONCLUSION:Using the sideport for the creation of the capsulorhexis leads to a lesser drop in IOP during this maneuver compared to the main incision in enucleated porcine eyes.The use of different OVD has no significant influence on IOP drop.展开更多
Background: Dry eye and glaucoma are two common pathologies in the elderly, and are very often associated. This association suggests a link between them and between their treatments. Our purpose for this study is to d...Background: Dry eye and glaucoma are two common pathologies in the elderly, and are very often associated. This association suggests a link between them and between their treatments. Our purpose for this study is to determine the prevalence of dry eye in our glaucoma patients treated with eye drops and deduce the factors associated with it. Patients and Methods: We conducted a cross-sectional, analytical study from October 2022 to September 2023 in the ophthalmology department of Garoua Regional Hospital in glaucoma patients aged over 15 years able to answer the Ocular Surface Disease Index (OSDI) questionnaires and treated with antiglaucoma eye drops for more than 3 months. These patients underwent a complete ophthalmological examination and a tear film break-up time test. Results: A total of 73 patients (146 eyes) were examined. The average age of the patients was 47.2 ± 16.5 years, with a male predominance of 54.8%. The prevalence of dry eye syndrome in our patients according to the OSDI score was 56.2% (95% CI) (44.8;67.6). The prevalence of dry eye syndrome on clinical examination of the BUT in the right eye was 83.7% (95% CI) (75.1;92.1) and 79.4% (70.2;88.7) in the left eye. The duration of antiglaucoma treatment was the factor associated with dry eye syndrome (p < 0.05) in glaucoma patients in our setting. Conclusion: Dry Eye Syndrome is common in glaucoma patients on drops in our setting. Treatment duration of more than 1 year seems to be associated with dry eyes.展开更多
To evaluate the efficacy of online learning and explore the impact of long-term use of electronic products on facial skin as well as eyes.A cross-sectional survey was conducted to 180 sophomores in Xi′an Jiaotong Uni...To evaluate the efficacy of online learning and explore the impact of long-term use of electronic products on facial skin as well as eyes.A cross-sectional survey was conducted to 180 sophomores in Xi′an Jiaotong University by cluster random sampling from September to October 2021.The questionnaire covering study condition,skin lesion and Ocular Surface Disease Index.χ_(2) test was used to compare the facial skin condition among different groups,and spearman correlation test was used to test the correlation of rank data.During online education,students′learning pressure is reduced,their autonomy is improved,and the learning efficiency is reduced.There were differences in the incidence of facial itching and papules among different groups.Duration of use of electronic products was positively correlated with the facial itching,with an r value of 0.231(P<0.05);the proportion of pigmentation in non-blue light protection groups(12.8%)was higher than that in blue light protection groups(1.7%),the difference was statistically significant(χ_(2)=8.384,P<0.05).The prevalence of dry eye among college students is 66.7%,and the proportion of moderate to severe dry eye is 34.5%.The study autonomy has been improved during online teaching.Long-term use of electronic products and no blue light protection have an impact on facial skin.Students should enhance the knowledge of skin-care and eye-care and develop better habits.展开更多
Age-related macular degeneration is a serious neurodegenerative disease of the retina that significantly impacts vision.Unfortunately,the specific pathogenesis remains unclear,and effective early treatment options are...Age-related macular degeneration is a serious neurodegenerative disease of the retina that significantly impacts vision.Unfortunately,the specific pathogenesis remains unclear,and effective early treatment options are consequently lacking.The microbiome is defined as a large ecosystem of microorganisms living within and coexisting with a host.The intestinal microbiome undergoes dynamic changes owing to age,diet,genetics,and other factors.Such dysregulation of the intestinal flora can disrupt the microecological balance,resulting in immunological and metabolic dysfunction in the host,and affecting the development of many diseases.In recent decades,significant evidence has indicated that the intestinal flora also influences systems outside of the digestive tract,including the brain.Indeed,several studies have demonstrated the critical role of the gut-brain axis in the development of brain neurodegenerative diseases,including Alzheimer’s disease and Parkinson’s disease.Similarly,the role of the“gut-eye axis”has been confirmed to play a role in the pathogenesis of many ocular disorders.Moreover,age-related macular degeneration and many brain neurodegenerative diseases have been shown to share several risk factors and to exhibit comparable etiologies.As such,the intestinal flora may play an important role in age-related macular degeneration.Given the above context,the present review aims to clarify the gut-brain and gut-eye connections,assess the effect of intestinal flora and metabolites on age-related macular degeneration,and identify potential diagnostic markers and therapeutic strategies.Currently,direct research on the role of intestinal flora in age-related macular degeneration is still relatively limited,while studies focusing solely on intestinal flora are insufficient to fully elucidate its functional role in age-related macular degeneration.Organ-on-a-chip technology has shown promise in clarifying the gut-eye interactions,while integrating analysis of the intestinal flora with research on metabolites through metabolomics and other techniques is crucial for understanding their potential mechanisms.展开更多
BACKGROUND Emergency medical care is essential in preventing morbidity and mortality,especially when interventions are time-sensitive and require immediate access to supplies and trained personnel.AIM To assess the tr...BACKGROUND Emergency medical care is essential in preventing morbidity and mortality,especially when interventions are time-sensitive and require immediate access to supplies and trained personnel.AIM To assess the treatment rates of eye emergencies in Africa.Ocular emergencies are particularly delicate due to the eye’s intricate structure and the necessity for its refractive components to remain transparent.METHODS This review examines the low treatment rates of eye emergencies in Africa,drawing on 96 records extracted from the PubMed database using predetermined search criteria.RESULTS The epidemiology of ocular injuries,as detailed in the studies,reveals significant relationships between the incidence and prevalence of eye injuries and factors such as age,gender,and occupation.The causes of eye emergencies range from accidents to gender-based violence and insect or animal attacks.Management approaches reported in the review include both surgical and non-surgical interventions,from medication to evisceration or enucleation of the eye.Preventive measures emphasize eye health education and the use of protective eyewear and facial protection.However,inadequate healthcare infrastructure and personnel,cultural and geographical barriers,and socioeconomic and behavioral factors hinder the effective prevention,service uptake,and management of eye emergencies.CONCLUSION The authors recommend developing eye health policies,enhancing community engagement,improving healthcare personnel training and retention,and increasing funding for eye care programs as solutions to address the low treatment rate of eye emergencies in Africa.展开更多
Although eye problems can occur at any age, they are often common from the age of 40. Eye diseases with a prevalence associated with age and aging will continue to increase in the coming years. Most studies conducted ...Although eye problems can occur at any age, they are often common from the age of 40. Eye diseases with a prevalence associated with age and aging will continue to increase in the coming years. Most studies conducted on problems in middle-aged people have focused on visual disorders without taking into account all the ocular morbidities that may affect this segment of the population, hence the present study, the aim of which is to determine the proportions of different eye diseases in people aged 40 and over. Materials and Methods: This was a descriptive cross-sectional study carried out in the ophthalmology department covering the period from January 1 to December 31, 2020. Results: In total, we collected 828 patients aged 40 and over out of 1811 patients who received ophthalmological consultation during the study period, representing 45.72%. The most represented age group was 40 - 50 years, with an average age of 58.84 years and a maximum of 93 years. There were slightly more women (62.3%) than men (37.7%). The main reasons for consultation were decreased visual acuity (26.4%) and pruritus (19.9%). The main eye diseases diagnosed were cataracts (23%), allergic conjunctivitis (21.1%), and bacterial conjunctivitis (14.2%). Discussions: The predominance of cataracts in the diagnosed diseases confirms the literature data, according to which the main eye morbidities in middle-aged and elderly people are cataracts, glaucoma, and age-related macular degeneration. Conclusion: It is crucial to have a mastery of these epidemiological data of eye diseases in order to adapt the technical platforms of eye care structures to the needs of different segments of the population.展开更多
Hurston's work Their Eyes Were Watching God receives much attention and has been analyzed from different angles.This paper tries to explore the double consciousness in it to shown how the blacks can survive under ...Hurston's work Their Eyes Were Watching God receives much attention and has been analyzed from different angles.This paper tries to explore the double consciousness in it to shown how the blacks can survive under the influence of double con?sciousness.展开更多
AIM: To examine the refractive prediction error in high myopic eyes after phacovitrectomy.METHODS: This retrospective comparative case series included 91 eyes(18 high myopic eyes and 73 non-high myopic eyes) of 91 pat...AIM: To examine the refractive prediction error in high myopic eyes after phacovitrectomy.METHODS: This retrospective comparative case series included 91 eyes(18 high myopic eyes and 73 non-high myopic eyes) of 91 patients who underwent successful phacovitrectomy(phacoemulsification, intraocular lens implantation, and pars plana vitrectomy). The high myopic eyes were defined as the eye with more than 26.0mm of axial length. The postoperative prediction error of mean error and mean absolute error were evaluated at4 mo postoperatively. Axial length and keratometry measurement were performed preoperatively and 4mo postoperatively using the IOL Master.RESULTS: The refractive outcome after phacovitrectomy showed significantly greater myopic shift in the high myopic eyes [-1.08 ±0.87 diopters(D)] than that in the non-high myopic eyes(-0.43 ±0.63 D, P =0.004). Axial length and keratometric value in the high myopic eyes were significantly increased(P =0.043, 0.037 respectively),whereas those in the non-high myopic group were not significantly increased(P =0.135, 0.347 respectively). The change of the axial length in the myopic eye(0.46±0.28 mm)was greater than that in the non- high myopic eye(0.11 ± 0.34 mm; P 【0.001).CONCLUSION: High myopic eyes showed more myopic shift than non-high myopic eyes after phacovitrectomy.The cause of myopic shift in high myopic eyes seems tobe attributed to actual elongation of the axial length in high myopia.展开更多
AIM: To investigate the changes of retinal thickness in macula of high myopic eyes using spectral domain optical coherence tomography(OCT). ·METHODS: Middle-aged and young myopic patients were divided into three ...AIM: To investigate the changes of retinal thickness in macula of high myopic eyes using spectral domain optical coherence tomography(OCT). ·METHODS: Middle-aged and young myopic patients were divided into three groups according to their refractive error/axial length: low and medium myopia group(LMMG),high myopia group(HMG) and super high myopia group(SHMG). Cirrus HD-OCT was used to evaluate total average macular thickness,central subfield thickness,inner/outer macular thickness and macular volume. The differences among experimental groups were analyzed by one-factor analysis of variance. Associations between macular thickness and refractive error/axial length were analyzed by Pearson correlation analysis. ·RESULTS: There was no significant difference in age among the three groups(P =0.2789). The mean refraction error in the LMMG,HMG,and SHMG groups was-2.49 ± 1.38D,-8.53 ±1.95D and-13.88 ±1.76D,respectively(P 【 0.001). The central subfield thickness of three groups was 244.56 ±12.19μm,254.33 ±11.61μm and 261.75 ± 11.83μm,respectively,and there were statistically significance between random two groups. The total average macular thickness,inner/outer macular thickness,and macular volume decreased with increased myopia/axial length. Average foveal thickness had negative correlations with refractive error(P 【0.001),and positive correlations with axial length. The inferior and temporal inner macular thickness,all the quadrants of outer ring,total average macular thickness and macular volume featured positive correlations with refractive error,and negative correlations with axial length. Average foveal thickness,superior and temporal innermacular thicknesses,and temporal outer macular thickness was lower in females compared to males. ·CONCLUSION: With an increase in myopia degree/axial length,the average foveal thickness increased and the inner/outer macular thickness decreased. Females featured thicker average foveal thickness,and thinner macular thickness compared to males.展开更多
AIM:To compare the efficacy and complications of Artisan iris-claw intraocular lens(IOL)implantation and posterior chamber IOL sulcus fixation for the treatment of aphakic eyes without capsular support after vitrectom...AIM:To compare the efficacy and complications of Artisan iris-claw intraocular lens(IOL)implantation and posterior chamber IOL sulcus fixation for the treatment of aphakic eyes without capsular support after vitrectomy.METHODS:A prospective study of 45 cases was conducted.Forty-five eyes without sufficient lens capsule support following pars plana vitrectomy(PPV)combined lens extraction were divided into two groups.Group A:25 eyes received Artisan iris-claw IOL implantation.Group B:20 eyes received posterior chamber IOL sulcus fixation.The corrected distance visual acuity(CDVA)and intraocular pressure(IOP),corneal endothelial cell loss rate,surgical time and complications were compared between the two groups.Pigment changes of trabecular meshwork and anterior chamber depths were measured at each time point in Artisan group.RESULTS:The mean surgical time of Artisan group was significantly shorter(P【0.05).No statistically significant difference in endothelial cell loss rate was noted between two groups at any time point(P】0.05).CDVA of Artian group was better than that of the sulcus fixation group 1d after surgery(P【0.05)and there was no statistically significant difference 1 and 3mo after surgery(P】0.05).Mean IOP showed no significant differences between groups before and after surgery.The postoperative complications of Artisan group were anterior uveitis,iris depigmentation,pupillary distortion and spontaneous lens dislocation.The complications of sulcus fixation group include choroidal detachment,intraocular haemorrhage,tilt of IOL optic part and retinal detachment.CONCLUSION:Secondary Artisan IOL implantation canbe performed less invasively and in a shorter surgical time period with earlier visual recovery after surgery compared to transscleral suturing fixation of an IOL.This technique is an effective and safe procedure.It is a promising option for the treatment of aphakic eyes without capsular support after vitrectomy.展开更多
AIM:To describe and compare the corneal endothelial cell density and morphology in young,low and moderate myopic Chinese adults in Malaysian Chinese population.·METHODS:Non-contact specular microscopy(Topcon SP30...AIM:To describe and compare the corneal endothelial cell density and morphology in young,low and moderate myopic Chinese adults in Malaysian Chinese population.·METHODS:Non-contact specular microscopy(Topcon SP3000P,Tokyo,Japan) was performed in low(n =78;21.22±1.51 years) and moderate(n =78;21.82±1.40 years)myopic subjects.The mean of three consecutive measurements of endothelial cell density(MCD),coefficient of variation(CV) in the cell size,and hexagonal appearance of the cell were obtained.·RESULTS:In low myopic eyes the MCD was 3 063.0±176.2/mm2,the mean CV was 33.4 ±4.0% and the mean hexagonal appearance of the cell was 57.9 ±2.7%.In moderate myopic eyes the MCD was 2961.6 ±159.0/mm2,the mean CV was 33.9 ±3.6% and mean hexagonal appearance of the cell was 56.2 ±4.7%.There were statistically significant differences in MCD(P 【0.000) and hexagonal appearance of the cell(P 【0.005) between low and moderate myopic eyes.·CONCLUSION:The corneal endothelial cell layer in more myopic eyes tends to have less MCD and cell hexagonality compared to lower myopic eyes.Nevertheless,there is no significant difference in CV between low and moderate myopic eyes.展开更多
The present study aimed to compare the clinical efficacy of a 0.4% carbomer gel and 1% carboxymethyl cellulose (CMC) containing artificial tears in treatment of dry eye patients. Sixty subjects with mean age of 45.8...The present study aimed to compare the clinical efficacy of a 0.4% carbomer gel and 1% carboxymethyl cellulose (CMC) containing artificial tears in treatment of dry eye patients. Sixty subjects with mean age of 45.89 years who had symptoms and signs of dry eye were enrolled in this prospective, investigator-masked and stratified random sampling study. The subjects were divided into two parallel groups with 30 subjects (60 eyes) in each group. One group received carbomer gel, and the other group received 1% CMC containing artificial tears. Subjects received the drops 3 to 4 times or more per day for 3 months. At the first visit time, the precorneal residence time of these two drops was measured. The efficacy was assessed by comparing the subjective symptoms (ocular dry- ness, foreign body sensation, burning sensation and pain), and the objective test results of tears breakup time, Schirmer's test and corneal fluorescein staining prior to the study and after the treat- ment. As a result, the ocular residence time of carbomer gel was significantly longer than that of 1% CMC (P〈0.001). Most of the primary subjective symptoms and objective test results were improved after treatment in both carbomer gel group and 1% CMC group. As to the improvement of each symptom and objective test result, carbomer gel was more effective than 1% CMC group (P〈0.01). In conclusion, carbomer gel had longer precorneal residence time and was more effective than 1% CMC in the treatment of patients with dry eyes.展开更多
AIM: To evaluate the efficacy of surgical treatment of vitrectomy combined with silicone oil tamponade in the treatment of severely traumatized eyes with the visual acuity of no light perception (NLP).METHODS: This wa...AIM: To evaluate the efficacy of surgical treatment of vitrectomy combined with silicone oil tamponade in the treatment of severely traumatized eyes with the visual acuity of no light perception (NLP).METHODS: This was a retrospective uncontrolled interventional case-series of 19 patients of severely traumatized eyes with NLP who underwent vitrectomy surgery at the Affiliated Hospital of Medical College, Qingdao University (Qingdao, China) during a 3-year period. We recorded perioperative factors with the potential to influence functional outcome including duration from the injury to intervention; causes for ocular trauma; open globe or closed globe injury; grade of vitreous hemorrhage; grade of endophthalmitis; grade of retinal detachment; size and location of intraocular foreign body (IOFB); extent and position of retinal defect; grade of proliferative vitreoretinopathy (PVR); type of surgery; perioperative complications and tamponade agent. The follow-up time was from 3 to 18 months, and the mean time was 12 months.RESULTS: After a mean follow-up period of 12 months (3-18 months) 10.53% (2/19) of eyes had visual acuity of between 20/60 and 20/400, 52.63% (10/19) had visual acuity less than 20/400 but more than NLP, and 36.84% (7/19) remained NLP. Visual acuity was improved from NLP to light perception (LP) or better in 63.16% (12/19) of eyes and the rate of complete retinal reattachment was 73.68% (14/19). Good visual acuity all resulted from those patients of blunt trauma with intact eyewall (closed globe injury). The perioperative factors of poor visual acuity prognosis included delayed intervention; open globe injury; endophthalmitis; severe retinal detachment; large IOFB; macular defect; a wide range of retinal defects andsevere PVR.CONCLUSION: The main reasons of NLP after ocular trauma are severe vitreous hemorrhage opacity; refractive media opacity; retinal detachment; retinal and uveal damages and defects, especially defects of the macula; PVR and endophthalmitis. NLP after ocular trauma in some cases does not mean permanent vision loss. Early intervention of vitrectomy combined with silicone oil tamponade and achieving retinal reattachment of the remaining retina, may make the severely traumatized eyes regain the VA of LP or better.展开更多
In this study, we aimed to study the pattern visual evoked potentials (P-VEPs) in two eyes with varying visual acuity in one eye and to provide an objective estimation of visual acuity by comparing P-VEPs in one and...In this study, we aimed to study the pattern visual evoked potentials (P-VEPs) in two eyes with varying visual acuity in one eye and to provide an objective estimation of visual acuity by comparing P-VEPs in one and two eyes. Thirty subjects were chosen, who had one eye with an acuity of 5.0, 4.85, 4.6, 4.0, or scieropia and obstructed vision and the other eye with an acuity of 5.0, respectively. P-VEPs were detected under the large grating stimuli at 3x4 spatial frequency, moderate grating stimuli (12× 16 spatial frequency) and small grating stimuli (48×64 spatial frequency). Under large grating stimuli, there was no significant difference in P100 peak latency between the groups, nor was there a significant difference between the amplitude of two eyes and the amplitude of one normal-vision eye. Under moderate and small grating stimuli, there was a significant difference in P100 peak latency between the group with both eyes having an acuity of 5.0 and the group with visual acuity below 4.0 in one eye. There was a significant difference in P100 amplitude between the group with visual acuity of 5.0 in both eyes and the group with one normal-vision eye. There was no significant difference in the amplitude of two eyes and the amplitude of one normal-vision eye between any other two groups. In forensic identification, characteristics and variability of P-VEPs in one and two eyes can be used to identify malingering or decline in visual acuity.展开更多
Conventional moving target detection focuses on algorithms to improve detection efficiency. These algorithms pay less attention to the image acquisition means, and usually solve specific problems. This often results i...Conventional moving target detection focuses on algorithms to improve detection efficiency. These algorithms pay less attention to the image acquisition means, and usually solve specific problems. This often results in poor flexibility and reus- ability. Insect compound eyes offer unique advantages for moving target detection and these advantages have attracted the attention of many researchers in recent years. In this paper we proposed a new system for moving target detection. We used the detection mechanism of insect compound eyes for the simulation of the characteristics of structure, control, and function. We discussed the design scheme of the system, the development of the bionic control circuit, and introduced the proposed mathe- matical model of bionic cqmpound eyes for data acquisition and object detection. After this the integrated system was described and discussed. Our paper presents a novel approach for moving target detection. This approach effectively tackles some of the well-known problems in the field of view, resolution, and real-time processing problems in moving target detection.展开更多
Compound eyes are unique optical imaging systems that consist of numerous separate light-sensitive units(ommatidia).Attempts have been made to produce artificial compound eyes via advanced 3 D nanotechnologies.Among t...Compound eyes are unique optical imaging systems that consist of numerous separate light-sensitive units(ommatidia).Attempts have been made to produce artificial compound eyes via advanced 3 D nanotechnologies.Among them,femtosecond laser direct writing(FsLDW)technology has emerged as an effective strategy due to its distinct advantages in 3 D designable and high precision fabrication capability.However,the point-by-point scanning process results in a very low fabrication efficiency,limiting the practical applications of the FsLDW technology.To solve this problem,we propose a high-efficiency method for the mass production of 3 D artificial compound eyes using a photopolymer template fabricated by FsLDW.The resultant 3 D SU-8 compound eye templates could be used to replicate polydimethylsiloxane(PDMS)compound eyes many times(over 50 times)with a highly improved efficiency(nearly 20 times higher than the efficiency of direct fabrication using the point-by-point FsLDW).The PDMS replicas showed good focusing and imaging performances.We anticipate that this method may serve as an enabler for the mass production of 3 D artificial compound eyes and promote their practical applications in the near future.展开更多
Planar and curved microlens arrays(MLAs)are the key components of miniaturized microoptical systems.In order to meet the requirements for advanced and multipurpose applications in microoptical field,a simple manufactu...Planar and curved microlens arrays(MLAs)are the key components of miniaturized microoptical systems.In order to meet the requirements for advanced and multipurpose applications in microoptical field,a simple manufacturing method is urgently required for fabricating MLAs with unique properties,such as waterproofness and variable field-of-view(FOV)imaging.Such properties are beneficial for the production of advanced artificial compound eyes for the significant applications in complex microcavity environments with high humidity,for instance,miniature medical endoscopy.However,the simple and effective fabrication of advanced artificial compound eyes still presents significant challenges.In this paper,bioinspired by the natural superhydrophobic surface of lotus leaf,we propose a novel method for the fabrication of waterproof artificial compound eyes.Electrohydrodynamic jet printing was used to fabricate hierarchical MLAs and nanolens arrays(NLAs)on polydimethylsiloxane film.The flexible film of MLAs hybridized with NLAs exhibited excellent superhydrophobic property with a water contact angle of 158°.The MLAs film was deformed using a microfluidics chip to create artificial compound eyes with variable FOV,which ranged from 0°to 160°.展开更多
The geometric characteristics of tropical cyclone(TC) eyes before landfall in South China are examined using groundbased radar reflectivity. It is found that the median and mean eye area decrease with TC intensity, ...The geometric characteristics of tropical cyclone(TC) eyes before landfall in South China are examined using groundbased radar reflectivity. It is found that the median and mean eye area decrease with TC intensity, except for the severe typhoon category, and the eye size increases with height. The increasing rate of eye size is relatively greater in upper layers.Moreover, the ratio of eye size change in the vertical direction does not correlate with TC intensity. No relationship is presented between the ratio of eye size change in the vertical direction and the vertical wind shear. No relationship between the vertical change in eye size and the eye size at a certain level is found, inconsistent with other studies. No relationship exists between the vertical change in eye size and the intensity tendency. The eye roundness values range mainly from 0.5 to 0.7, and more intense TCs generally have eyes that are more circular.展开更多
文摘AIM:To evaluate the effectiveness and safety of intravitreal ranibizumab(IVR)for diabetic macular edema(DME)in vitrectomized versus non-vitrectomized eyes.METHODS:The PubMed,EMBASE,Web of Science,Cochrane,EBSCO were comprehensively searched for studies comparing vitrectomized and non-vitrectomized eyes with DME.Clinical outcomes of best-corrected visual acuity(BCVA),central macular thickness(CMT),the mean number of intravitreal injection and adverse events were extracted and analyzed.RESULTS:Six studies involving 641 eyes were included.Final visual gain significantly improved and CMT significantly reduced in vitrectomized eyes at 6mo and 12mo visits(P<0.05).Although the mean reduction in CMT among non-vitrectomized eyes was significantly greater than in vitrectomized eyes at the 6mo[mean difference(MD)=53.57,95%confidence interval(CI):28.03 to 78.72,P<0.0001]and 12mo(MD=49.65,95%CI:19.58 to 79.72,P=0.01),no significant difference was detected in improvement in BCVA at either 6mo(MD=0.05,95%CI:-0.02 to 0.13,P=0.14)or 12mo(MD=0.03,95%CI:-0.04 to 0.09,P=0.43).Injection number of ranibizumab in non-vitrectomized eyes was significantly less than that in vitrectomized eyes during 6-month period(MD=0.60,95%CI:0.16 to 1.04,P=0.008),while there was no statistically significant difference between the two groups during 12mo of follow-up.CONCLUSION:Evidence from current study suggests that IVR was useful for both vitrectomized group and nonvitrectomized group with DME.Although less reduction in macular thickness is found in vitrectomized group,visual improvement between two groups is similar.
文摘This narrative review aimed to have an algorithmic approach to microphthalmos by a systematic search.The definition can be related to a number of special phenotypes.In the more challenging cases of complex microphthalmos,relative anterior microphthalmos,and nanophthalmos,the surgeon can approach these cases more safely if they have a deep understanding of the anatomical variations and ideal formulae for intraocular lens computation and knows how to avoid intra-and post-operative complications.In this article,we review the criteria by which we recognize and describe pre-,intra-,and post-operative considerations,as well as discuss the ideal intraocular lenses for microphthalmos,given the intricate varieties of small eye phenotypes.
文摘AIM:To investigate the influence of ophthalmic viscoelastic devices(OVDs)and different surgical approaches on the intraocular pressure(IOP)before and after creation of the curvilinear circular capsulorhexis(CCC)as a measure for anterior chamber stability during this maneuver.METHODS:Prospective experimental WetLab study carried out on enucleated porcine eyes.IOP was measured before and after CCC with the iCare Rebound tonometer(iCare ic200;iCare Finland Oy,Vantaa,Finland).The OVDs used were a cohesive one[Z-Hyalin,Carl Zeiss Meditec AG,Germany;hyaluronic acid(HA)]and a dispersive[Z-Celcoat,Carl Zeiss Meditec AG,Germany;hydroxy propylmethylcellulosis(HPMC)].The CCC was created using Utrata forceps or 23 g microforceps in different combinations with the OVDs.RESULTS:Using the Utrata forceps the IOP dropped from 63.65±6.44 to 11.25±3.63 mm Hg during the CCC.The use of different OVDs made no difference.Using the 23 g microforceps the IOP dropped from 65.35±8.15 to 36.55±6.09 mm Hg.The difference between IOP drop using either Utrata forceps or 23 g microforceps was highly significant regardless of the OVD used.CONCLUSION:Using the sideport for the creation of the capsulorhexis leads to a lesser drop in IOP during this maneuver compared to the main incision in enucleated porcine eyes.The use of different OVD has no significant influence on IOP drop.
文摘Background: Dry eye and glaucoma are two common pathologies in the elderly, and are very often associated. This association suggests a link between them and between their treatments. Our purpose for this study is to determine the prevalence of dry eye in our glaucoma patients treated with eye drops and deduce the factors associated with it. Patients and Methods: We conducted a cross-sectional, analytical study from October 2022 to September 2023 in the ophthalmology department of Garoua Regional Hospital in glaucoma patients aged over 15 years able to answer the Ocular Surface Disease Index (OSDI) questionnaires and treated with antiglaucoma eye drops for more than 3 months. These patients underwent a complete ophthalmological examination and a tear film break-up time test. Results: A total of 73 patients (146 eyes) were examined. The average age of the patients was 47.2 ± 16.5 years, with a male predominance of 54.8%. The prevalence of dry eye syndrome in our patients according to the OSDI score was 56.2% (95% CI) (44.8;67.6). The prevalence of dry eye syndrome on clinical examination of the BUT in the right eye was 83.7% (95% CI) (75.1;92.1) and 79.4% (70.2;88.7) in the left eye. The duration of antiglaucoma treatment was the factor associated with dry eye syndrome (p < 0.05) in glaucoma patients in our setting. Conclusion: Dry Eye Syndrome is common in glaucoma patients on drops in our setting. Treatment duration of more than 1 year seems to be associated with dry eyes.
文摘To evaluate the efficacy of online learning and explore the impact of long-term use of electronic products on facial skin as well as eyes.A cross-sectional survey was conducted to 180 sophomores in Xi′an Jiaotong University by cluster random sampling from September to October 2021.The questionnaire covering study condition,skin lesion and Ocular Surface Disease Index.χ_(2) test was used to compare the facial skin condition among different groups,and spearman correlation test was used to test the correlation of rank data.During online education,students′learning pressure is reduced,their autonomy is improved,and the learning efficiency is reduced.There were differences in the incidence of facial itching and papules among different groups.Duration of use of electronic products was positively correlated with the facial itching,with an r value of 0.231(P<0.05);the proportion of pigmentation in non-blue light protection groups(12.8%)was higher than that in blue light protection groups(1.7%),the difference was statistically significant(χ_(2)=8.384,P<0.05).The prevalence of dry eye among college students is 66.7%,and the proportion of moderate to severe dry eye is 34.5%.The study autonomy has been improved during online teaching.Long-term use of electronic products and no blue light protection have an impact on facial skin.Students should enhance the knowledge of skin-care and eye-care and develop better habits.
基金supported by the National Natural Science Foundation of China,No.82171080Nanjing Medical Science and Technology Development Project,No.YKK23264Postgraduate Research&Practice Innovation Program of Jiangsu Province,Nos.JX10414151,JX10414152(all to KL)。
文摘Age-related macular degeneration is a serious neurodegenerative disease of the retina that significantly impacts vision.Unfortunately,the specific pathogenesis remains unclear,and effective early treatment options are consequently lacking.The microbiome is defined as a large ecosystem of microorganisms living within and coexisting with a host.The intestinal microbiome undergoes dynamic changes owing to age,diet,genetics,and other factors.Such dysregulation of the intestinal flora can disrupt the microecological balance,resulting in immunological and metabolic dysfunction in the host,and affecting the development of many diseases.In recent decades,significant evidence has indicated that the intestinal flora also influences systems outside of the digestive tract,including the brain.Indeed,several studies have demonstrated the critical role of the gut-brain axis in the development of brain neurodegenerative diseases,including Alzheimer’s disease and Parkinson’s disease.Similarly,the role of the“gut-eye axis”has been confirmed to play a role in the pathogenesis of many ocular disorders.Moreover,age-related macular degeneration and many brain neurodegenerative diseases have been shown to share several risk factors and to exhibit comparable etiologies.As such,the intestinal flora may play an important role in age-related macular degeneration.Given the above context,the present review aims to clarify the gut-brain and gut-eye connections,assess the effect of intestinal flora and metabolites on age-related macular degeneration,and identify potential diagnostic markers and therapeutic strategies.Currently,direct research on the role of intestinal flora in age-related macular degeneration is still relatively limited,while studies focusing solely on intestinal flora are insufficient to fully elucidate its functional role in age-related macular degeneration.Organ-on-a-chip technology has shown promise in clarifying the gut-eye interactions,while integrating analysis of the intestinal flora with research on metabolites through metabolomics and other techniques is crucial for understanding their potential mechanisms.
文摘BACKGROUND Emergency medical care is essential in preventing morbidity and mortality,especially when interventions are time-sensitive and require immediate access to supplies and trained personnel.AIM To assess the treatment rates of eye emergencies in Africa.Ocular emergencies are particularly delicate due to the eye’s intricate structure and the necessity for its refractive components to remain transparent.METHODS This review examines the low treatment rates of eye emergencies in Africa,drawing on 96 records extracted from the PubMed database using predetermined search criteria.RESULTS The epidemiology of ocular injuries,as detailed in the studies,reveals significant relationships between the incidence and prevalence of eye injuries and factors such as age,gender,and occupation.The causes of eye emergencies range from accidents to gender-based violence and insect or animal attacks.Management approaches reported in the review include both surgical and non-surgical interventions,from medication to evisceration or enucleation of the eye.Preventive measures emphasize eye health education and the use of protective eyewear and facial protection.However,inadequate healthcare infrastructure and personnel,cultural and geographical barriers,and socioeconomic and behavioral factors hinder the effective prevention,service uptake,and management of eye emergencies.CONCLUSION The authors recommend developing eye health policies,enhancing community engagement,improving healthcare personnel training and retention,and increasing funding for eye care programs as solutions to address the low treatment rate of eye emergencies in Africa.
文摘Although eye problems can occur at any age, they are often common from the age of 40. Eye diseases with a prevalence associated with age and aging will continue to increase in the coming years. Most studies conducted on problems in middle-aged people have focused on visual disorders without taking into account all the ocular morbidities that may affect this segment of the population, hence the present study, the aim of which is to determine the proportions of different eye diseases in people aged 40 and over. Materials and Methods: This was a descriptive cross-sectional study carried out in the ophthalmology department covering the period from January 1 to December 31, 2020. Results: In total, we collected 828 patients aged 40 and over out of 1811 patients who received ophthalmological consultation during the study period, representing 45.72%. The most represented age group was 40 - 50 years, with an average age of 58.84 years and a maximum of 93 years. There were slightly more women (62.3%) than men (37.7%). The main reasons for consultation were decreased visual acuity (26.4%) and pruritus (19.9%). The main eye diseases diagnosed were cataracts (23%), allergic conjunctivitis (21.1%), and bacterial conjunctivitis (14.2%). Discussions: The predominance of cataracts in the diagnosed diseases confirms the literature data, according to which the main eye morbidities in middle-aged and elderly people are cataracts, glaucoma, and age-related macular degeneration. Conclusion: It is crucial to have a mastery of these epidemiological data of eye diseases in order to adapt the technical platforms of eye care structures to the needs of different segments of the population.
文摘Hurston's work Their Eyes Were Watching God receives much attention and has been analyzed from different angles.This paper tries to explore the double consciousness in it to shown how the blacks can survive under the influence of double con?sciousness.
文摘AIM: To examine the refractive prediction error in high myopic eyes after phacovitrectomy.METHODS: This retrospective comparative case series included 91 eyes(18 high myopic eyes and 73 non-high myopic eyes) of 91 patients who underwent successful phacovitrectomy(phacoemulsification, intraocular lens implantation, and pars plana vitrectomy). The high myopic eyes were defined as the eye with more than 26.0mm of axial length. The postoperative prediction error of mean error and mean absolute error were evaluated at4 mo postoperatively. Axial length and keratometry measurement were performed preoperatively and 4mo postoperatively using the IOL Master.RESULTS: The refractive outcome after phacovitrectomy showed significantly greater myopic shift in the high myopic eyes [-1.08 ±0.87 diopters(D)] than that in the non-high myopic eyes(-0.43 ±0.63 D, P =0.004). Axial length and keratometric value in the high myopic eyes were significantly increased(P =0.043, 0.037 respectively),whereas those in the non-high myopic group were not significantly increased(P =0.135, 0.347 respectively). The change of the axial length in the myopic eye(0.46±0.28 mm)was greater than that in the non- high myopic eye(0.11 ± 0.34 mm; P 【0.001).CONCLUSION: High myopic eyes showed more myopic shift than non-high myopic eyes after phacovitrectomy.The cause of myopic shift in high myopic eyes seems tobe attributed to actual elongation of the axial length in high myopia.
文摘AIM: To investigate the changes of retinal thickness in macula of high myopic eyes using spectral domain optical coherence tomography(OCT). ·METHODS: Middle-aged and young myopic patients were divided into three groups according to their refractive error/axial length: low and medium myopia group(LMMG),high myopia group(HMG) and super high myopia group(SHMG). Cirrus HD-OCT was used to evaluate total average macular thickness,central subfield thickness,inner/outer macular thickness and macular volume. The differences among experimental groups were analyzed by one-factor analysis of variance. Associations between macular thickness and refractive error/axial length were analyzed by Pearson correlation analysis. ·RESULTS: There was no significant difference in age among the three groups(P =0.2789). The mean refraction error in the LMMG,HMG,and SHMG groups was-2.49 ± 1.38D,-8.53 ±1.95D and-13.88 ±1.76D,respectively(P 【 0.001). The central subfield thickness of three groups was 244.56 ±12.19μm,254.33 ±11.61μm and 261.75 ± 11.83μm,respectively,and there were statistically significance between random two groups. The total average macular thickness,inner/outer macular thickness,and macular volume decreased with increased myopia/axial length. Average foveal thickness had negative correlations with refractive error(P 【0.001),and positive correlations with axial length. The inferior and temporal inner macular thickness,all the quadrants of outer ring,total average macular thickness and macular volume featured positive correlations with refractive error,and negative correlations with axial length. Average foveal thickness,superior and temporal innermacular thicknesses,and temporal outer macular thickness was lower in females compared to males. ·CONCLUSION: With an increase in myopia degree/axial length,the average foveal thickness increased and the inner/outer macular thickness decreased. Females featured thicker average foveal thickness,and thinner macular thickness compared to males.
文摘AIM:To compare the efficacy and complications of Artisan iris-claw intraocular lens(IOL)implantation and posterior chamber IOL sulcus fixation for the treatment of aphakic eyes without capsular support after vitrectomy.METHODS:A prospective study of 45 cases was conducted.Forty-five eyes without sufficient lens capsule support following pars plana vitrectomy(PPV)combined lens extraction were divided into two groups.Group A:25 eyes received Artisan iris-claw IOL implantation.Group B:20 eyes received posterior chamber IOL sulcus fixation.The corrected distance visual acuity(CDVA)and intraocular pressure(IOP),corneal endothelial cell loss rate,surgical time and complications were compared between the two groups.Pigment changes of trabecular meshwork and anterior chamber depths were measured at each time point in Artisan group.RESULTS:The mean surgical time of Artisan group was significantly shorter(P【0.05).No statistically significant difference in endothelial cell loss rate was noted between two groups at any time point(P】0.05).CDVA of Artian group was better than that of the sulcus fixation group 1d after surgery(P【0.05)and there was no statistically significant difference 1 and 3mo after surgery(P】0.05).Mean IOP showed no significant differences between groups before and after surgery.The postoperative complications of Artisan group were anterior uveitis,iris depigmentation,pupillary distortion and spontaneous lens dislocation.The complications of sulcus fixation group include choroidal detachment,intraocular haemorrhage,tilt of IOL optic part and retinal detachment.CONCLUSION:Secondary Artisan IOL implantation canbe performed less invasively and in a shorter surgical time period with earlier visual recovery after surgery compared to transscleral suturing fixation of an IOL.This technique is an effective and safe procedure.It is a promising option for the treatment of aphakic eyes without capsular support after vitrectomy.
文摘AIM:To describe and compare the corneal endothelial cell density and morphology in young,low and moderate myopic Chinese adults in Malaysian Chinese population.·METHODS:Non-contact specular microscopy(Topcon SP3000P,Tokyo,Japan) was performed in low(n =78;21.22±1.51 years) and moderate(n =78;21.82±1.40 years)myopic subjects.The mean of three consecutive measurements of endothelial cell density(MCD),coefficient of variation(CV) in the cell size,and hexagonal appearance of the cell were obtained.·RESULTS:In low myopic eyes the MCD was 3 063.0±176.2/mm2,the mean CV was 33.4 ±4.0% and the mean hexagonal appearance of the cell was 57.9 ±2.7%.In moderate myopic eyes the MCD was 2961.6 ±159.0/mm2,the mean CV was 33.9 ±3.6% and mean hexagonal appearance of the cell was 56.2 ±4.7%.There were statistically significant differences in MCD(P 【0.000) and hexagonal appearance of the cell(P 【0.005) between low and moderate myopic eyes.·CONCLUSION:The corneal endothelial cell layer in more myopic eyes tends to have less MCD and cell hexagonality compared to lower myopic eyes.Nevertheless,there is no significant difference in CV between low and moderate myopic eyes.
文摘The present study aimed to compare the clinical efficacy of a 0.4% carbomer gel and 1% carboxymethyl cellulose (CMC) containing artificial tears in treatment of dry eye patients. Sixty subjects with mean age of 45.89 years who had symptoms and signs of dry eye were enrolled in this prospective, investigator-masked and stratified random sampling study. The subjects were divided into two parallel groups with 30 subjects (60 eyes) in each group. One group received carbomer gel, and the other group received 1% CMC containing artificial tears. Subjects received the drops 3 to 4 times or more per day for 3 months. At the first visit time, the precorneal residence time of these two drops was measured. The efficacy was assessed by comparing the subjective symptoms (ocular dry- ness, foreign body sensation, burning sensation and pain), and the objective test results of tears breakup time, Schirmer's test and corneal fluorescein staining prior to the study and after the treat- ment. As a result, the ocular residence time of carbomer gel was significantly longer than that of 1% CMC (P〈0.001). Most of the primary subjective symptoms and objective test results were improved after treatment in both carbomer gel group and 1% CMC group. As to the improvement of each symptom and objective test result, carbomer gel was more effective than 1% CMC group (P〈0.01). In conclusion, carbomer gel had longer precorneal residence time and was more effective than 1% CMC in the treatment of patients with dry eyes.
文摘AIM: To evaluate the efficacy of surgical treatment of vitrectomy combined with silicone oil tamponade in the treatment of severely traumatized eyes with the visual acuity of no light perception (NLP).METHODS: This was a retrospective uncontrolled interventional case-series of 19 patients of severely traumatized eyes with NLP who underwent vitrectomy surgery at the Affiliated Hospital of Medical College, Qingdao University (Qingdao, China) during a 3-year period. We recorded perioperative factors with the potential to influence functional outcome including duration from the injury to intervention; causes for ocular trauma; open globe or closed globe injury; grade of vitreous hemorrhage; grade of endophthalmitis; grade of retinal detachment; size and location of intraocular foreign body (IOFB); extent and position of retinal defect; grade of proliferative vitreoretinopathy (PVR); type of surgery; perioperative complications and tamponade agent. The follow-up time was from 3 to 18 months, and the mean time was 12 months.RESULTS: After a mean follow-up period of 12 months (3-18 months) 10.53% (2/19) of eyes had visual acuity of between 20/60 and 20/400, 52.63% (10/19) had visual acuity less than 20/400 but more than NLP, and 36.84% (7/19) remained NLP. Visual acuity was improved from NLP to light perception (LP) or better in 63.16% (12/19) of eyes and the rate of complete retinal reattachment was 73.68% (14/19). Good visual acuity all resulted from those patients of blunt trauma with intact eyewall (closed globe injury). The perioperative factors of poor visual acuity prognosis included delayed intervention; open globe injury; endophthalmitis; severe retinal detachment; large IOFB; macular defect; a wide range of retinal defects andsevere PVR.CONCLUSION: The main reasons of NLP after ocular trauma are severe vitreous hemorrhage opacity; refractive media opacity; retinal detachment; retinal and uveal damages and defects, especially defects of the macula; PVR and endophthalmitis. NLP after ocular trauma in some cases does not mean permanent vision loss. Early intervention of vitrectomy combined with silicone oil tamponade and achieving retinal reattachment of the remaining retina, may make the severely traumatized eyes regain the VA of LP or better.
文摘In this study, we aimed to study the pattern visual evoked potentials (P-VEPs) in two eyes with varying visual acuity in one eye and to provide an objective estimation of visual acuity by comparing P-VEPs in one and two eyes. Thirty subjects were chosen, who had one eye with an acuity of 5.0, 4.85, 4.6, 4.0, or scieropia and obstructed vision and the other eye with an acuity of 5.0, respectively. P-VEPs were detected under the large grating stimuli at 3x4 spatial frequency, moderate grating stimuli (12× 16 spatial frequency) and small grating stimuli (48×64 spatial frequency). Under large grating stimuli, there was no significant difference in P100 peak latency between the groups, nor was there a significant difference between the amplitude of two eyes and the amplitude of one normal-vision eye. Under moderate and small grating stimuli, there was a significant difference in P100 peak latency between the group with both eyes having an acuity of 5.0 and the group with visual acuity below 4.0 in one eye. There was a significant difference in P100 amplitude between the group with visual acuity of 5.0 in both eyes and the group with one normal-vision eye. There was no significant difference in the amplitude of two eyes and the amplitude of one normal-vision eye between any other two groups. In forensic identification, characteristics and variability of P-VEPs in one and two eyes can be used to identify malingering or decline in visual acuity.
基金The work presented in this paper is supported by the Scholarship for International Young Scientists of NSFC (National Natural Science Foundation of China) (1D: 41050110441).
文摘Conventional moving target detection focuses on algorithms to improve detection efficiency. These algorithms pay less attention to the image acquisition means, and usually solve specific problems. This often results in poor flexibility and reus- ability. Insect compound eyes offer unique advantages for moving target detection and these advantages have attracted the attention of many researchers in recent years. In this paper we proposed a new system for moving target detection. We used the detection mechanism of insect compound eyes for the simulation of the characteristics of structure, control, and function. We discussed the design scheme of the system, the development of the bionic control circuit, and introduced the proposed mathe- matical model of bionic cqmpound eyes for data acquisition and object detection. After this the integrated system was described and discussed. Our paper presents a novel approach for moving target detection. This approach effectively tackles some of the well-known problems in the field of view, resolution, and real-time processing problems in moving target detection.
基金supported by the National Natural Science Foundation of China(NSFC)under Grant Nos.#61935008,#61590930,#61775078,and#61605055
文摘Compound eyes are unique optical imaging systems that consist of numerous separate light-sensitive units(ommatidia).Attempts have been made to produce artificial compound eyes via advanced 3 D nanotechnologies.Among them,femtosecond laser direct writing(FsLDW)technology has emerged as an effective strategy due to its distinct advantages in 3 D designable and high precision fabrication capability.However,the point-by-point scanning process results in a very low fabrication efficiency,limiting the practical applications of the FsLDW technology.To solve this problem,we propose a high-efficiency method for the mass production of 3 D artificial compound eyes using a photopolymer template fabricated by FsLDW.The resultant 3 D SU-8 compound eye templates could be used to replicate polydimethylsiloxane(PDMS)compound eyes many times(over 50 times)with a highly improved efficiency(nearly 20 times higher than the efficiency of direct fabrication using the point-by-point FsLDW).The PDMS replicas showed good focusing and imaging performances.We anticipate that this method may serve as an enabler for the mass production of 3 D artificial compound eyes and promote their practical applications in the near future.
基金The authors wish to acknowledge the funding provided by the National Natural Science Foundation of China(Grant Nos.61727811,61703395,91748212,U1613220,and 61821005)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(Grant No.YJKYYQ20180027)+2 种基金the External Cooperation Program of the Chinese Academy of Sciences(Grant No.173321KYSB20170015)Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.Y201943)LiaoNing Revitalization Talents Program(Grant No.XLYC1807006).
文摘Planar and curved microlens arrays(MLAs)are the key components of miniaturized microoptical systems.In order to meet the requirements for advanced and multipurpose applications in microoptical field,a simple manufacturing method is urgently required for fabricating MLAs with unique properties,such as waterproofness and variable field-of-view(FOV)imaging.Such properties are beneficial for the production of advanced artificial compound eyes for the significant applications in complex microcavity environments with high humidity,for instance,miniature medical endoscopy.However,the simple and effective fabrication of advanced artificial compound eyes still presents significant challenges.In this paper,bioinspired by the natural superhydrophobic surface of lotus leaf,we propose a novel method for the fabrication of waterproof artificial compound eyes.Electrohydrodynamic jet printing was used to fabricate hierarchical MLAs and nanolens arrays(NLAs)on polydimethylsiloxane film.The flexible film of MLAs hybridized with NLAs exhibited excellent superhydrophobic property with a water contact angle of 158°.The MLAs film was deformed using a microfluidics chip to create artificial compound eyes with variable FOV,which ranged from 0°to 160°.
基金supported by the National (Key) Basic Research and Development (973) Program of China (Grant No.2015CB452803)the National Key Research and Development Program of China (Grant No.2017YFC1501601)+2 种基金the National Natural Science Foundation of China (Grant Nos.41475058,41730961 and 41575083)the Basic Research Fund of CAMS (Grant No.2016Z003)the Top-notch Academic Programs Project of Jiangsu Higher Education Institutions (TAPP)
文摘The geometric characteristics of tropical cyclone(TC) eyes before landfall in South China are examined using groundbased radar reflectivity. It is found that the median and mean eye area decrease with TC intensity, except for the severe typhoon category, and the eye size increases with height. The increasing rate of eye size is relatively greater in upper layers.Moreover, the ratio of eye size change in the vertical direction does not correlate with TC intensity. No relationship is presented between the ratio of eye size change in the vertical direction and the vertical wind shear. No relationship between the vertical change in eye size and the eye size at a certain level is found, inconsistent with other studies. No relationship exists between the vertical change in eye size and the intensity tendency. The eye roundness values range mainly from 0.5 to 0.7, and more intense TCs generally have eyes that are more circular.