Control Lenses Research Articles

New photochromic spectacle lenses improve glare discomfort and photostress recovery

PurposeTo investigate the influence of a new photochromic spectacle lens on glare discomfort (GD) and photostress recovery time (PRT) in normal healthy subjects. A subject-masked within-subject comparison was performed using the fully activated state of Transitions® Gen STM and clear control. Methods30 participants (M = 19.2 ± 1.3 years) were tested. GD was assessed both physically, by measuring palpebral fissure size, and subjectively, via a 5-point Likert scale. PRT was measured as the amount of time necessary to regain visual function after an intense (∼15 % bleach) 5-second exposure to a broadband (emulated sunlight) light stressor. ResultsGD, measured both physically and subjectively was significantly reduced (p < 0.001) when participants viewed the stimulus through the test lens compared to the clear control lens. PRT was also significantly reduced when using the test lens (p < 0.001). ConclusionsThese data are consistent with past findings but show that they apply to a commonly used photochromic tint. The results highlight the potential of specialized lenses to enhance visual comfort and performance in varying lighting conditions.

Accommodative behaviour and retinal defocus in highly myopic eyes fitted with a dual focus myopia control contactlens.

To evaluate the myopic and hyperopic defocus delivered to the retina by a dual focus (DF) myopia control contact lens when myopia exceeds 6.00 D. Individuals with high myopia were fitted bilaterally with high-powered DF lenses containing power profiles matching a Coopervision MiSight 1 day contact lens (omafilcon A) and a Coopervision Proclear 1 day single vision (SV) lens. Wavefront measurements along the primary line of sight and across the central ±20° of the horizontal retina were acquired using a pyramidal aberrometer, while subjects accommodated to high-contrast letter stimuli (6/12 equivalent) at six target vergences (-0.25 and -1.00 to -5.00 D). Linear mixed-effects regression models explored the relationship between the spherical equivalent refractive error (SERE) and induced defocus. Thirteen teenagers and young adults (ages 13-32 years, mean [standard deviation, SD] age = 22.8 [4.9] years) with high myopia (SERE -6.50 to -9.25 D) were tested. The treatment optic zone of the DF lens shifted retinal defocus by the expected -2.00 D, with a mean (SD) difference (DF-SV) of -2.21 (0.18) D for the inner treatment ring. Inclusion of the treatment optic had no significant impact on accommodative accuracy (p = 0.51). Accommodative lags were larger at the nearer viewing distances, with lag increasing by approximately 0.30 D for every additional dioptre of SERE. Measured retinal defocus within the annular treatment zone was approximately -2.00 D at the foveal centre, 10° nasal and temporal and 20° nasal and reduced to -1.90 (0.57) D at 20° temporal. Relative to eyes with lower levels of myopia, the increased accommodative lags and more prolate retinas of highly myopic eyes reduced the myopic retinal defocus from the DF myopia control lens, while the treatment optical zones generated the combined effect of reducing hyperopic and introducing myopic retinal defocus relative to an SV correction.

Efficacy comparison of repeated low-level red-light therapy and orthokeratology lenses for myopia control.

This study aimed to compare and analyze the efficacy of repeated low-level red-light therapy and orthokeratology lenses for myopia control in children. Exactly 138 participants were enrolled in this retrospective study. Comprehensive eye examinations were performed prior to treatment. The repeated low-level red-light therapy and orthokeratology lenses groups comprised 67 and 71 patients, respectively. The age range was between 6 and 14 years, with myopia of ≤-0.50 D and astigmatism of ≤2.50 D after cycloplegia. Follow-up data were collected during the initial visit and the treatment period. Changes in axial length over a 2-year period and associated factors were analyzed. Over the 2-year period, the repeated low-level red-light therapy group exhibited significantly less axial length growth compared with the orthokeratology lenses group (0.17 ± 0.40 vs. 0.50 ± 0.27 mm, p<0.001). In the first year, the axial length growth in the repeated low-level red-light therapy group was significantly less than that in the orthokeratology lenses group (0.03 ± 0.22 vs. 0.28 ± 0.18 mm, p<0.001), with no significant difference observed in the second year (0.14 ± 0.29 vs. 0.21 ± 0.14 mm, p=0.06). The repeated low-level red-light therapy group showed a 55% reduction in axial length after 1 month and a 42% reduction after 1 year, compared with 4% and 3% reductions in the orthokeratology lenses group, respectively. Linear mixed-effects model analysis indicated that the annual axial length change rate in the repeated low-level red-light therapy group was 0.10 mm (95% confidence interval [CI], 0.07 to 0.14), compared with 0.25 mm in the orthokeratology lenses group (95% CI, 0.24 to 0.27), with an average difference of 0.15 mm (95% CI, -0.17 to -0.12, p<0.001). Repeated low-level red-light therapy demonstrated slightly superior efficacy in controlling myopia progression in children compared with orthokeratology lenses.

Comfort advantages demonstrated with a novel soft contact lens: A randomized clinical trial

PurposeTo compare comfort outcomes between a novel daily disposable contact lens – designed to maximize comfort – and an established control. The hypothesis was that the test lens would be superior to the control for four key comfort questionnaire items: end-of-day comfort, all-day comfort, visual comfort while driving at night, and reduction of ocular fatigue from digital device use. MethodsThis randomized, controlled, subject-masked, parallel-arm study enrolled young (18–39 years), healthy, myopic, contact lens wearers with an up-to-date prescription at 19 investigational sites in the United States. Subjects wore either the test (ACUVUE® OASYS MAX 1-Day, senofilcon A) or control (Dailies Total1®, delefilcon A) lens for 2 weeks of bilateral, daily disposable wear before completing comfort questionnaire items, each of which had 5 or 6 response options. For each item, the odds ratio for positive (top-two-box) responses was estimated from a binomial generalized linear mixed model. A gatekeeping approach combined with the truncated Hochberg procedure was used for multiplicity adjustment. ResultsOf 344 enrolled subjects, 342 subjects were randomized and dispensed lenses, with 171 subjects per lens group. Among the 342 subjects, 68.4% were female, 83.6% were White, and the average age was 29.7 (±5.53) years. The test lens was statistically superior to the control for all four comfort questions: odds ratios (test vs. control) were 2.01 (95% CI: 1.25, 3.22) for end-of-day comfort, 2.17 (alpha-adjusted CI: 1.30, 3.64) for all-day comfort, 2.00 (alpha-adjusted CI: 1.18, 3.41) for reducing ocular fatigue from digital device use, and 1.77 (95% CI: 1.04, 3.02) for comfortable vision while driving at night. ConclusionThe test lens demonstrated statistically superior physical and visual comfort, as measured by the four comfort endpoints, compared to the control. The test lens had significantly greater odds of favorable responses for all comfort items compared to the control.

Foveal neural adaptation to optically induced contrast reduction.

Contrast processing is suggested to interact with eye growth and myopia development. A novel contrast-reducing myopia control lens design decreases image contrast and was shown to slow myopia progression. Limited insights exist regarding neural visual processing following adaptation to image contrast reduction. This study investigated foveal neural contrast sensitivity in 29 young adults following a 30-minute adaptation to scattering using a Bangerter occlusion foil 0.8, +0.5-diopter defocus, and a clear lens control condition. Neural contrast sensitivity at its peak sensitivity of 6 cycles per degree was assessed before and after adaptation to the lens conditions, employing a unique interferometric system. Pre-adaptation measurements were averaged from six replicates and post-adaptation measurements by the first and last three of six replicates. The change in neural contrast sensitivity was largest for scattering across the first and last three post-adaptation measurements (+0.05±0.01logCS and +0.04±0.01logCS, respectively) compared with control and defocus (all +0.03±0.01logCS). For scattering, the observed increase of neural contrast sensitivity within the first three measurements differed significantly from the pre-adaptation baseline (p = 0.04) and was significantly higher compared with the control condition (p = 0.04). The sensitivity increases in the control and defocus conditions were not significant (all p > 0.05). As the adaptation effect diminished, no significant differences were found from baseline or between the conditions in the last three measurements (all p > 0.05). When post-adaptation neural contrast sensitivities were clustered into 25-second sequences, a significant effect was observed between the conditions, with only a significant relevant effect between control and scattering at 25 seconds (p = 0.04) and no further significant effects (all p > 0.05). The alteration in neural contrast sensitivity at peak sensitivity was most pronounced following adaptation to the scattering condition compared with defocus and control, suggesting that induced scattering might be considered for myopia control.

A protocol for a single center, randomized, controlled trial assessing the effects of spectacles or orthokeratology on dry eye parameters in children and adolescents

BackgroundThe prevalence of myopia among adolescents is increasing precipitously in China, and the popularity of orthokeratology (OK) lenses as an effective treatment for controlling myopia progression is rising. This protocol assessed and compared the clinical dry eye parameters in children and adolescents with myopia treated with spectacles or OK lenses. Methods and analysisThis single-masked randomized control trial will include 300 participants (aged 8–17 years) with myopia treated with OK lens (study group) or spectacles (control group). We will record the ocular surface disease index, visual analog scale score, noninvasive tear breakup time, tear meniscus height, meibomian gland score, ocular redness score, visual acuity, tear Matrix Metalloproteinase-9 concentration, tear Lymphotoxin alpha levels at baseline, and after 1-, 3-, 6-, and 12-month. DiscussionThis study will be a standardized, scientific, clinical trial designed to evaluate the dry eye parameters in children and adolescents with myopia treated with OK lenses for myopia control. Ethics and disseminationThis study has been approved by the Ethics Committee of He Eye Specialist Hospital [ethics approval number: IRB(2023)K024.01]. Before participating in the trial, written informed consent will be obtained from all patient's parents or guardians. The findings of this study will be showcased at both local and international conferences and will also be submitted for publication in reputable peer-reviewed journals. Trial registration numberClinicaltrials.gov: NCT06023108 {2a, 2b}

Refractive power profiles of commercially available soft multifocal contact lenses for myopia control.

Lens power profiles can provide valuable insights on the imposed optical defocus and visual experience of contact lens wearers, especially in the context of myopia control. This study measured the refractive power profiles of multifocal soft contact lenses (MFCLs) currently used or that have the potential for use in myopia control using high spatial resolution aberrometry. The instrument's repeatability for determining MFCLs power profiles was also assessed. The power profiles of 10 MFCLs of various designs (centre-distance, centre-near and extended depth of focus) were measured using the Lambda-X NIMOEVO, a phase shifting Schlieren-based device. Power profiles were graphically expressed as measured power at each chord position and the maximum add power was calculated. The repeatability of the NIMOEVO was expressed as the within-subject standard deviation at each chord position for a subset of five MFCLs. The measured distance powers differed from nominal powers for more than half of the MFCLs with a definable distance zone. There were variations in the chord position of the distance and near correction zones, rate of power transitions and calculated maximum add between the MFCLs which did not depend on lens design. For half of the MFCLs, the power profile shape was inconsistent between different nominal back vertex powers of the same design. The repeatability of the NIMOEVO was dependent on the lens design, with designs featuring faster rates of power change exhibiting worse repeatability. Significant differences in MFCL power profiles were found which were not adequately represented in labelling. This is likely due to the small number of parameters used to define lens power characteristics. Eye health care practitioners should be aware of potential differences in power profiles between different MFCLs, which will impact the retinal defocus introduced during lens wear and the wearer's visual experience.

Subjective impressions with myopia control contact lenses versus single vision lenses: A systematic review and meta-analysis

PurposeTo gain insight into patients’ visual experiences and satisfaction when using different forms of myopia control lenses. MethodsPubMed, Cochrane Library, Embase, Scopus and Web of Science databases were searched for articles assessing subjective visual quality with myopia control lenses compared with single-vision lenses (SVLs) up to July 10, 2023. Eight-hundred-and-three articles were retrieved, reviewed and any questionnaire items on subjective impressions of lens wear were meta-analysed. Subgroup analyses were based on the magnitude of defocus (add power) of multifocal soft contact lenses (MFSCLs) and age groups. A random-effects model was employed for meta-analysis, and I2 statistic used to assess the statistical heterogeneity. ResultsNineteen articles fit the criteria, but only six articles involving MFSCLs had relevant data. MFSCLs were associated with lower subjective ratings of vision at different distances compared to SVLs (p < 0.001), but the differences were less than one unit. MFSCLs also yielded lower ratings when moving or walking and/or climbing stairs at −0.38 (−0.69 to −0.07, p = 0.02; I2 = 85 %, p < 0.001) and for subjective comfort (difference of −0.23, −0.41 to −0.05, p = 0.01; I2 = 63 %, p < 0.001). Subjective ratings for playing sports were not different between groups. Experience with MFSCLs was rated lower by young adults compared to children for all variables. In both children and young adults, ratings were lower with higher add compared to lower add MFSCLs. ConclusionAlthough subjective ratings for vision and comfort were lower with MFSCLs compared to SVLs, the difference was mostly less than one unit. Importantly, young adults rated their visual experience lower compared to children.

Choosing between bad and worse: investigating choice in moral dilemmas through the lens of control.

People's preferences for the utilitarian outcome in sacrificial moral dilemmas, where a larger group of individuals are saved at the cost of a few, have been argued to be influenced by various factors. Taking expected utility (EU) theory into consideration, we investigate whether the expected effectiveness of actions elucidate certain inconsistencies in moral judgments. Additionally, we also explore whether participants' role in the dilemma as the executor or a superior who merely makes a decision, which is carried out by a subordinate, influences judgments-a factor generally overlooked by classical EU models. We test these hypotheses using a modified moral dilemma paradigm with a choice between two actions, one highly successful and the other more likely to fail. Both actions are either expected to result in a favorable outcome of saving five individuals by sacrificing one or an unfavorable outcome of sacrificing five to save one. When the efficient action is anticipated to lead to a favorable outcome, in line with EU models, people almost invariably choose the efficient action. However, in conditions where the EUs associated with efficient and inefficient actions are close to each other, people's choice for favored outcome is above chance when they act as agents themselves. We discuss the implications of our results for existing theories of moral judgments.

Rege Ribaldum: Participatory Punishment in the Pursuit of Urban Justice in Late Medieval Southern France

Abstract Utilizing the lens of popular control to assess criminal sentences highlights the significance of effective public agency in the later Middle Ages, instead of political oppression, especially in the urban realm. The people who inhabited cities played a participatory role in setting the parameters involved in the spectacles of judicial chastisement by accepting or rejecting what unfolded before them. And this became a way in which neighbors surveilled and corrected both the residents who lived in their midst, and the agents of authority expected to orchestrate restitution through performative executions. This article unpacks jurisdictional disputes from the city of Toulouse, in order to analyze the notion of accountability among the inhabitants and of citizens over judicial officers, especially in crimes involving contested sexuality. In 1332, for example, a customary punishment known as a rege ribaldum (where authorities forced a criminal to run the streets of the town) spiraled out of control at the hands of one of the spectators, resulting in a gruesome disfigurement. Rather than dismiss this event as senseless mob violence, concepts of popular control shed light on the cooperative element of the officers and their people as it informed the distribution of punishment, rooted in principles that were sometimes congruent, and sometimes not.

Spectral transmission of commercially available high-energy visible light-filtering spectacle lenses.

High-energy visible (HEV) light-filtering spectacle lenses are being widely promoted despite limited evidence to support their use. The spectral transmission properties of commercially available lenses varied, particularly in the HEV light region, and they do not perform in the same way for transmission of ultraviolet (UV)-A and HEV light. Although HEV light is important for several visual and nonvisual functions, there are concerns over the potential adverse effects of increased HEV light exposure. High-energy visible light-filtering spectacle lenses are being widely marketed to promote ocular health and improve sleep by reducing exposure to HEV light. This study reports on the spectral transmission characteristics of commercially available HEV light-filtering spectacle lenses based on the recommendations of the Spectral Bands Task Force technical report. The spectral transmission of light through nine afocal plastic lenses, including eight commercially available HEV light-filtering lenses and one clear uncoated control lens, was evaluated using a Cary 5000 UV-Vis-NIR spectrophotometer (Agilent Technologies, Johannesburg, South Africa) for wavelengths 250 to 780 nm. The percentage transmission values are reported for UV radiation and visible light, with emphasis for HEV light (380 to 500 nm) and the three subbands therein. All lenses blocked UV-C and UV-B radiation (250 to 315 nm). For UV-A radiation (315 to 380 nm), six lenses showed optimal 100% absorption, whereas three lenses allowed ≤12%. The transmission values for the HEV light-filtering lenses ranged from 55 to 90% and 75 to 95% for HEV light of wavelengths 400 to 455 nm and 455 to 500 nm, respectively. In contrast, the control lens showed 92 (400 to 455 nm) and 93% (455 to 500 nm) transmission. The HEV light-filtering spectacle lenses varied in their transmission properties and do not necessarily perform in the same way for transmission of UV-A and HEV light. Optometric personnel should consider these transmission properties, particularly for HEV light, when making recommendations to patients about HEV light-filtering spectacle lenses.

The efficacy and safety of combination therapy of repeated low-level red light and defocus-incorporated multiple segments spectacle lenses for myopia control in children: the study protocol for a 12-month, randomized, parallel-controlled, and single-center clinical trial

BackgroundMyopia is increasing in prevalence worldwide. Combination therapy showed a better effect on myopia control than monotherapy. Repeated low-level red light therapy (RLRL) therapy and defocus-incorporated multiple segment (DIMS) spectacle lenses have been reported to retard myopia progression significantly. However, whether these two therapies are better than one is still unknown. The present study aims to report the study protocol of a trial designed to evaluate the efficacy and safety of combination therapy of RLRL and DIMS versus DIMS alone for reducing the progression of myopia among Chinese school-aged children.MethodsThis study is a 12-month, randomized, parallel-controlled, single-center clinical trial. We will recruit children aged 8–12 years with spherical equivalence (SE) between − 0.50 D and − 6.00 D under cycloplegia in both eyes. We will recruit 66 participants with an allocation ratio of 1:1 from our hospital. Participants in the intervention group will be treated with an RLRL therapy device twice a day from Monday to Friday at home, 3 min per session, with a minimum interval of 4 h, under the supervision of their parents/guardians. They will wear DIMS spectacles for myopia correction during the day. Participants in the control group will not receive the RLRL therapy and will only wear DIMS spectacles to correct myopia. Participants from both groups will attend the hospital every 6 months.The primary outcome is the change in axial length at 12 months. Secondary outcomes include changes in refraction under cycloplegia, optical coherence tomography (OCT), multifocal electroretinogram (mfERG), color vision, and participants’ self-reporting of adverse events at 12 months.DiscussionThis study will report the efficacy and safety outcome of the combination therapy of RLRL and DIMS versus DIMS for school-aged children with myopia in detail.Trial registrationChiCTR2300075398. Registered 4 September 2023. https://www.chictr.org.cn/bin/project/edit?pid=200751.

Effect of compound treatments on mouse lens viscoelasticity

Previous studies have shown that pharmaceutical agents such as lipoic acid have the ability to soften the lens, presenting a promising avenue for treating presbyopia. One obstacle encountered in the preclinical stage of such agents is the need for precise measurements of lens elasticity in experimental models. This study aimed to evaluate the effects of 25-hydroxycholesterol, lipoic acid, and obeticholic acid on the viscoelastic properties of mouse lenses using a custom-built elastometer system. Data were acquired on lenses from C57BL/6J female mice from two age groups: young (age: 8–10 weeks) and old (age: 32–43 weeks). OD lenses were used as the control and OS lenses were treated. Control lenses were immersed in Dulbecco's Modified Eagle Medium (DMEM) and treatment lenses were immersed in a compound solution containing 25-hydroxycholesterol (5 young and 5 old), lipoic acid at 2.35 mM (5 young and 5 old), lipoic acid at 0.66 mM (5 old), or obeticholic acid (5 old) at 37 °C for 18 h. After treatment, the mouse lenses were placed in a DMEM-filled chamber within a custom-built elastometer system that recorded the load and lens shape as the lens was compressed by 600 μm at a speed of 50 μm/s. The load was continuously recorded during compression and during stress-relaxation. The compression phase was fit with a linear function to quantify lens stiffness. The stress-relaxation phase was fit with a 3-term exponential relaxation model providing relaxation time constants (t1, t2, t3), and equilibrium load. The lens stiffness, time constants and equilibrium load were compared for the control and treated groups. Results revealed an increase in stiffness with age for the control group (young: 1.16 ± 0.11 g/mm, old: 1.29 ± 0.14 g/mm) and relaxation time constants decreased with age (young: t1 = 221.9 ± 29.0 s, t2 = 24.7 ± 3.8 s, t3 = 3.12 ± 0.87 s, old: t1 = 183.0 ± 22.0 s, t2 = 20.6 ± 2.6 s and t3 = 2.24 ± 0.43 s). Among the compounds tested, only 25-hydroxycholesterol produced statistically significant changes in the lens stiffness, relaxation time constants, and equilibrium load. In conclusion, older mouse lenses are stiffer and less viscous than young mouse lenses. Notably, no significant change in lens stiffness was observed following treatment with lipoic acid, contrary to previous findings.

Correction to “Universal Approximation Power of Deep Residual Neural Networks Through the Lens of Control”

Correction to “Universal Approximation Power of Deep Residual Neural Networks Through the Lens of Control”

Impact of defocus incorporated multiple segments (DIMS) spectacle lenses for myopia control on quality of life of the children: a qualitative study

ObjectiveTo assess the impact of DIMS (defocus incorporated multiple segments) spectacle lenses on the quality of life of children using it.MethodsSeparate in-depth interviews were conducted with children using DIMS as...

Dynamics of diseases spreading on networks in the forms of reaction-diffusion systems

In the face of persistent threats posed by infectious diseases, despite remarkable medical advancements, understanding and efficiently controlling their spatial spread through mathematical modeling remain imperative. Networked reaction-diffusion systems offer a promising avenue to effectively delineate population discrete distribution and individual movement heterogeneity. However, the dynamics of spatial diseases within these systems and the formulation of optimal control strategies are currently undergoing vigorous development. In this letter, we illustrate the dynamics of spatial disease spread in networked reaction-diffusion systems through the lens of optimal control, considering various network complexities from pairwise networks to higher-order networks. It then emphasizes their applicability in designing effective spatial disease control strategies across diverse network complexities. Finally, we discuss the existing challenges.

Novel Lenslet-ARray-Integrated Spectacle Lenses for Myopia Control: A 1-Year Randomized, Double-Masked, Controlled Trial

PurposeTo investigate the myopia control efficacy of novel Lenslet-ARray-Integrated (LARI) spectacle lenses with positive (PLARI) and negative (NLARI) power lenslets worn for one year in myopic children. DesignRandomized, double-masked, controlled clinical trial. ParticipantsA total of 240 children, aged 6 to 12 years, with spherical equivalent refraction (SER) between -4.00 and -1.00 diopter (D), astigmatism of 1.50 D or less, and anisometropia of 1.00 D or less. MethodsParticipants were assigned randomly in a 1:1:1 ratio to PLARI, NLARI, and a control (single-vision (SV)) groups. Cycloplegic autorefraction and axial length were measured at baseline and 6-month intervals after lens wear. Main Outcome MeasuresChanges in SER, axial elongation (AE), and differences between groups. ResultsAfter 1-year, SER changes and AE in the PLARI and NLARI groups were significantly less than those in the SV group (SER: -0.30 ± 0.48 D, -0.21 ± 0.35 D, -0.66 ± 0.40 D; AE: 0.19 ± 0.20 mm, 0.17 ± 0.14 mm, 0.34 ± 0.18 mm, respectively) (all P < 0.001). There were no significant differences in SER changes and AE between PLARI and NLARI groups (P = 0.54 and P = 1.00, respectively). Younger age was associated with more rapid SER increase and larger AE in the SV (r = 0.40, P < 0.001 and r = -0.59, P < 0.001, respectively) and PLARI (r= 0.46, P < 0.001 and r = -0.52, P < 0.001, respectively) groups, but not in the NLARI group (r = -0.002, P = 0.98 and r = -0.08, P = 0.48, respectively). ConclusionsCompared with the SV group, both PLARI and NARI groups showed significantly slower myopia progression in terms of SER and axial elongation. Faster myopia progression, in terms of both SER and AE, was associated with younger age in the SV and PLARI groups, but not in the NLARI group.

Language Policy Dynamics in Early Childhood Education through Basil Bernstein’s Lens

This paper examined the implementation of local language policy in privately owned early childhood centers through Bernstein’s lens theory. It focuses on the benefits and implications of using local languages as media of instruction in early grades drawing on Basil Bernstein’s framing and control lens. This study is qualitative in nature and it used descriptive research design to examine the implementation of local language policy in privately owned early childhood centers through Bernstein’s lens theory. Simple random sampling technique was used to select ten (10) privately owned centers and ten (10) teachers that formed the sample. Ten (10) center managers were purposely selected bringing the total number of participants to twenty (20). The study used participant and non-participant observation and interviews to collect data and a total of 10 lessons were observed with a focus on the language of the instruction used. The results of the study show that there are major divides that linger among the classes in society which are visible in geographical locations of schools and have a great influence on the language of instruction. The results further show that local languages are not taught in private schools due to limitations in language command and skill set required to adequately teach. The study recommends that the pre service training programs should equip early childhood education teachers with adequate skills in local language teaching. Further, there is need for wider consultation with all stakeholders if issues of medium of instruction are to be a consensus at pre-grade.

Impact of Peripheral Refractive Errors in Mobility Performance.

The purpose of this study was to investigate the functional effects of peripheral refractive errors on mobility performance through a stair negotiation task. Twenty-one young, normal sighted subjects navigated through an obstacle with steps, wearing spectacles that altered only their peripheral refraction. Lenses were used to induce positive defocus (+2 diopters [D] and +4 D), negative defocus (-2 D and -4 D), or astigmatism (+1.75 D and -3.75 D, axis 45 degrees) in the periphery. Feet trajectories were analyzed, and several gait assessment parameters were obtained. Statistical tests were conducted to determine significant performance differences between the lenses. Peripheral refraction in each subject was measured using a scanning Hartmann-Shack wavefront sensor to assess the impact of intrinsic peripheral refraction on the experiment. Statistically significant differences in performance appeared when peripheral errors were superimposed. Crossing time with respect to plano lenses increased by 6.2%, 7.6%, 19.2%, and 29.6% for the -2 D, +2 D, -4 D, and +4D lenses, respectively (P<0.05 in the last 3 cases). Subjects exhibited slower walking speeds, increased step count, and adopted precautionary measures. High-power positive defocus lenses had the biggest impact on performance, and differences were observed in distance to steps between induced positive and negative defocus. In this laboratory-based study without an adaptation period, peripheral refractive errors affected stair negotiation, causing cautious behavior in subjects. Performance differences among types of peripheral defocus may result from magnification effects and intrinsic peripheral refraction. These results highlight the importance of understanding the effects of induced peripheral errors by myopia control and intraocular lenses.

Developmental Heterogeneity of Rhabdomyosarcoma.

Rhabdomyosarcoma (RMS) is a pediatric embryonal solid tumor and the most common pediatric soft tissue sarcoma. The histology and transcriptome of RMS resemble skeletal muscle progenitor cells that have failed to terminally differentiate. Thus, RMS is typically thought to arise from corrupted skeletal muscle progenitor cells during development. However, RMS can occur in body regions devoid of skeletal muscle, suggesting the potential for nonmyogenic cells of origin. Here, we discuss the interplay between RMS driver mutations and cell(s) of origin with an emphasis on driving location specificity. Additionally, we discuss the mechanisms governing RMS transformation events and tumor heterogeneity through the lens of transcriptional networks and epigenetic control. Finally, we reimagine Waddington's developmental landscape to include a plane of transformation connecting distinct lineage landscapes to more accurately reflect the phenomena observed in pediatric cancers.