From Quaternary Carbon to Tertiary C(sp3)-Si and C(sp3)-Ge Bonds: Decyanative Coupling of Malononitriles with Chlorosilanes and Chlorogermanes Enabled by Ni/Ti Dual Catalysis.

Transition-metal-catalyzed C-Si/Ge cross-coupling offers promising avenues for the synthesis of organosilanes/organogermanes, yet it is fraught with long-standing challenges. A Ni/Ti-catalyzed strategy is reported here, allowing the use of disubstituted malononitriles as tertiary C(sp3) coupling partners to couple with chlorosilanes and chlorogermanes, respectively. This method enables the catalytic cleavage of the C(sp3)-CN bond of the quaternary carbon followed by the formation of C(sp3)-Si/C(sp3)-Ge bonds from ubiquitously available starting materials. The efficiency and generality are showcased by a broad scope for both of the coupling partners, therefore holding the potential to synthesize structurally diverse quaternary organosilanes and organogermanes that were difficult to access previously.

Optical development in the murine eye lens of accelerated senescence-prone SAMP8 and senescence-resistant SAMR1 strains.

The eye lens is responsible for focusing objects at various distances onto the retina and its refractive power is determined by its surface curvature as well as its internal gradient refractive index (GRIN). The lens continues to grow with age resulting in changes to the shape and to the GRIN profile. The present study aims to investigate how the ageing process may influence lens optical development. Murine lenses of accelerated senescence-prone strain (SAMP8) aged from 4 to 50 weeks; senescence-resistant strain (SAMR1) aged from 5 to 52 weeks as well as AKR strain (served as control) aged from 6 to 70 weeks were measured using the X-ray interferometer at the SPring-8 synchrotron Japan within three consecutive years from 2020 to 2022. Three dimensional distributions of the lens GRIN were reconstructed using the measured data and the lens shapes were determined using image segmentation in MatLab. Variations in the parameters describing the lens shape and the GRIN profile with age were compared amongst three mouse strains. With advancing age, both the lens anterior and posterior surface flattens and the lens sagittal thickness increase in all three mouse strains (Anterior radius of curvature increase at 0.008 mm/week, 0.007 mm/week and 0.002 mm/week while posterior radius of curvature increase at 0.002 mm/week, 0.007 mm/week and 0.003 mm/week respectively in AKR, SAMP8 and SAMR1 lenses). Compared with the AKR strain, the SAMP8 samples demonstrate a higher rate of increase in the posterior curvature radius (0.007 mm/week) and the thickness (0.015 mm/week), whilst the SAMR1 samples show slower increases in the anterior curvature radius (0.002 mm/week) and its thickness (0.013 mm/week). There are similar age-related trends in GRIN shape in the radial direction (in all three types of murine lenses nr2 and nr6 increase with age while nr4 decrease with age consistently) but not in the axial direction amongst three mouse strains (nz1 of AKR lens decrease while of SAMP8 and SAMR1 increase with age; nz2 of all three models increase with age; nz3 of AKR lens increase while of SAMP8 and SAMR1 decrease with age). The ageing process can influence the speed of lens shape change and affect the GRIN profile mainly in the axial direction, contributing to an accelerated decline rate of the optical power in the senescence-prone strain (3.5 D/week compared to 2.3 D/week in the AKR control model) but a retardatory decrease in the senescence-resistant strain (2.1 D/week compared to the 2.3D/week in the AKR control model).

Endoscopic resection of giant esophageal subepithelial lesions: experience from a large tertiary center.

BACKGROUND AND AIMS: Increased reports on endoscopic resection (ER) of esophageal giant subepithelial lesions (g-SELs) have emerged in recent years. The aim of this study was to evaluate the efficacy, technical difficulty, and safety through our single-center experience. METHODS: Seventy-five patients with g-SELs undergoing endoscopic resection were included in the training set. Clinicopathologic features, procedure-related characteristics, postprocedural outcomes, and follow-up data were analyzed. A predictive nomogram model for procedural difficulty was proposed based on the multivariable logistic regression analysis. Internal and external validations were conducted to verify the model performance. RESULTS: The overall en bloc resection rate was 93.3%. Intraoperative and postoperative adverse events occurred in 7 (9.3%) and 13 (17.3%) patients, respectively. No recurrence or metastasis was observed. Thirty-two (42.7%) patients underwent a difficult procedure. Age (adjusted odds ratio [aOR], .915; P = .004), maximal tumor diameter ≥8 cm (aOR, 9.896; P = .009), irregular shape (aOR, 4.081; P = .053), extraluminal growth pattern (aOR, 5.419; P = .011), and submucosal tunneling endoscopic resection (aOR, .109; P = .042) were found to be statistically or clinically significant factors for predicting endoscopic resection difficulty, based on which a nomogram model was developed. Internal and external validations of the nomogram via receiver-operating characteristic curves and calibration curves achieved favorable results. CONCLUSIONS: Endoscopic resection serves as a promising therapeutic option for esophageal g-SELs. A younger patient age, large tumor size, irregular shape, and extraluminal growth may indicate increased endoscopic resection difficulty, whereas a submucosal tunneling endoscopic resection procedure tends to be of lower difficulty. Our nomogram model performs well for predicting endoscopic resection difficulty for esophageal g-SELs.

Peroral endoscopic myotomy is an effective treatment for achalasia combined with hiatal hernia.

PURPOSE: To explore the feasibility of peroral endoscopic myotomy (POEM) in patients with achalasia and hiatal hernia. MATERIALS AND METHODS: We performed a retrospective review of 2136 patients with achalasia between January 2016 and December 2022. Patients with achalasia and hiatal hernia were assigned into study group, and matched patients with achalasia but no hiatal hernia were assigned into control group. The preoperative baseline information, procedure-related adverse events (AEs) and follow-up data were compared between the two groups. RESULTS: Hiatal hernia was identified in 56/1564 (3.6%) patients with achalasia. All of these patients underwent POEM with success. The preoperative baseline characteristics were similar between the study and control group. The study group presented with a similar rate of mucosal injury (12.5% vs 16.1, P = 0.589), pneumothorax (3.6% vs 1.8%, P = 1.000), pleural effusion (8.9% vs 12.5%, P = 0.541) and major AEs (1.8% vs 1.8%, P = 1.000) compared with the control group. As for the follow-up data, no significant differences were observed in clinical success (96.4% vs 92.9%, P = 0.679; 93.6% vs 94.0%, P = 1.000; 86.5% vs 91.4%, P = 0.711) clinical reflux (25.0% vs 19.6%, P = 0.496; 31.9% vs 26.0%, P = 0.521; 35.1% vs 31.4%, P = 0.739) and proton pump inhibitor usage (17.9% vs 16.1%, P = 0.801; 29.8% vs 24.0%, P = 0.520; 32.4% vs 25.7%, P = 0.531) between the study group and control group at 1-year, 2-year and 3-year follow-ups. CONCLUSIONS: POEM is a safe and effective treatment for achalasia combined with hiatal hernia.

Finite element analysis of zonular forces.

To determine the effect of zonular forces on lens capsule topography, a finite element (FE) analyses of lens capsules with no lens stroma and constant and variable thickness with anterior capsulotomies of 1.5 mm-6.5 mm were evaluated when subjected to equatorial (Ez), anterior (Az) and posterior (Pz) zonular forces. The lens capsule was considered in the unaccommodated state when the total initial zonular force was 0.00075 N or 0.3 N. From the total 0.00075 N zonular force, the Ez force was increased in 0.000125 N steps for a maximum force of 0.03 N and simultaneously the Az plus Pz force was reduced in 0.000125 N steps to zero. In addition, the force of all the zonules was reduced from 0.00075 N and separately from 0.3 N in 0.000125 N steps to zero. Only when Ez force was increased as Az and Pz force was reduced did the capsule topography simulate in vivo observations with the posterior capsule pole bowing posteriorly. The posterior bowing was directly related to Ez force and capsulotomy size. Whether the total force of all the zonules in the unaccommodated state was 0.00075 N or 0.3 N and reduced in steps to zero, the lens capsule topography did not emulate the in vivo observations. The FE analysis demonstrated that Ez tension increases while the Az and Pz tension decreases and that all the zonules do not relax during ciliary muscle contraction.

Endoscopic full-thickness resection, indication, methods and perspectives.

Minimally invasive surgery has emerged as the dominant theme of modern surgery, in which endoscopic surgery plays a key role. The technique of endoscopic surgery has evolved continuously with extensive research, improving the treatment modalities as well as expanding the indications for its use. As an active perforation endoscopic technique, endoscopic full-thickness resection (EFTR) is mainly used in the treatment of submucosal tumors (SMTs) of the gastrointestinal tract. With decades of evolution, EFTR has gradually developed into a mature endoscopic operation. Based on clinical experience and current research, indications, techniques, clinical outcomes and future perspectives for EFTR are discussed in this paper. We performed a bibliometric study on EFTR literature and showed robust data through a brief meta-analysis on the topic.

Coherent DOA Estimation Algorithm with Co-Prime Arrays for Low SNR Signals.

The Direction of Arrival (DOA) estimation of coherent signals in co-prime arrays has become a popular research topic. However, traditional spatial smoothing and subspace algorithms fail to perform well under low signal-to-noise ratio (SNR) and small snapshots. To address this issue, we have introduced an Enhanced Spatial Smoothing (ESS) algorithm that utilizes a space-time correlation matrix for de-noising and decoherence. Finally, an Estimating Signal Parameter via Rotational Invariance Techniques (ESPRIT) algorithm is used for DOA estimation. In comparison to other decoherence methods, when the SNR is -8 dB and the number of snapshots is 150, the mean square error (MSE) of the proposed algorithm approaches the Cramér-Rao bound (CRB), the probability of resolution (PoR) can reach over 88%, and, when the angular resolution is greater than 4°, the estimation accuracy can reach over 90%.

Optical development in the zebrafish eye lens.

The optics of the eye is the key to a functioning visual system. The exact nature of the correlation between ocular optics and eye development is not known because of the paucity of knowledge about the growth of a key optical element, the eye lens. The sophisticated optics of the lens and its gradient of refractive index provide the superior optical quality that the eye needs and which, it is thought, has a major influence on the development of proper visual function. The nature of a gradient refractive index lens, however, renders accurate measurements of its development difficult to make and has been the reason why the influence of lens growth on visual function remains largely unknown. Novel imaging techniques have made it possible to investigate growth of the eye lens in the zebrafish. This study shows measurements using X-ray Talbot interferometry of three-dimensional gradient index profiles in eye lenses of zebrafish from late larval to adult stages. The zebrafish lens shows evidence of a gradient of refractive index from the earliest stages measured and its growth suggests an apparent coincidence between periods of rapid increase in refractive index in the lens nucleus and increased expression of a particular crystallin protein group.

Predictive Value of CT Enterography Index for Postoperative Intra-abdominal Septic Complications in Patients With Crohn's Disease: Implications for Surgical Decision-Making.

BACKGROUND: Postoperative intra-abdominal septic complications in patients with Crohn's disease undergoing intestinal resection and anastomosis are frequent and difficult to manage. OBJECTIVE: This study sought to explore the value of preoperative CT enterography to predict intra-abdominal septic complications. DESIGN: This was a retrospective and prospective observational study. SETTINGS: This study was conducted in a tertiary referral hospital. PATIENTS: Patients with Crohn's disease undergoing primary intestinal resection were enrolled in our study. MAIN OUTCOME MEASURES: The CT enterography severity index was calculated and its ability to predict intra-abdominal septic complications evaluated by multivariate analyses. A prospective study was then performed to assess the reliability of this CT enterography index. RESULTS: The incidence of postoperative intra-abdominal septic complications in patients undergoing a 1-stage procedure was significantly higher than those undergoing a 2-stage procedure (3/103 vs 24/241; 2.9% vs 10.0%; p = 0.026). A multivariate analysis identified 5 CT enterography parameters, including mesenteric fibrofatty proliferation, intra-abdominal abscess or phlegmon, intestinal fistula, peritoneal effusion, and intestinal dilatation with stricture to be independent predictors of intra-abdominal septic complications (p < 0.001). A nomogram model based on these 5 parameters was constructed. A receiver operating characteristic analysis identified a CT enterography nomogram score cutoff of 175 as a predictor of intra-abdominal septic complications with a sensitivity of 83.3% and a specificity of 85.3%. In the prospective study, those patients with a CT enterography nomogram score >175 were assigned to the 2-stage group, which resulted in a similar intra-abdominal septic complication incidence in those undergoing intestinal resection with or without anastomosis (2/82 vs 2/34; p = 0.355). LIMITATIONS: This study was limited by its single-center scope. CONCLUSIONS: Preoperative CT enterography findings may predict postoperative outcomes and help determine surgical approach in Crohn's disease. Patients with worse intra-abdominal findings confirmed by CT enterography may benefit from stoma creation after intestinal resection. See Video Abstract at http://links.lww.com/DCR/B588. EL VALOR PREDICTIVO DEL NDICE ENTEROGRFICO POR TOMOGRAFA COMPUTADA PARA LAS COMPLICACIONES SPTICAS INTRAABDOMINALES POSTOPERATORIAS EN PACIENTES CON ENFERMEDAD DE CROHN IMPLICACIONES PARA LA TOMA DE DECISIONES QUIRRGICAS: ANTECEDENTES:Las complicaciones sépticas intra-abdominales postoperatorias en pacientes con enfermedad de Crohn sometidos a resección intestinal y anastomosis son frecuentes y difíciles de manejar.OBJETIVO:Este estudio buscó explorar el valor del índice enterográfico por tomografía computada en el pré-operatorio y así poder predecir futuras complicaciones sépticas intra-abdominales.DISEÑO:Estudio observacional retro-prospectivo.AJUSTE:Investigación realizada en un hospital de referencia terciaria.PACIENTES:Se incluyeron en nuestro estudio pacientes con enfermedad de Crohn sometidos a una resección intestinal primaria.PRINCIPALES MEDIDAS DE RESULTADO:Se calculó el índice de gravedad de la enterografía por tomografía axial computada y se evaluó su capacidad para predecir las complicaciones sépticas intra-abdominales mediante un análisis multivariado. Luego se realizó un estudio prospectivo para evaluar la confiabilidad del índice enterográfico por tomografía axial computada.RESULTADOS:La incidencia de complicaciones sépticas intra-abdominales postoperatorias en pacientes sometidos a un procedimiento de un solo tiempo fue significativamente mayor que aquellos sometidos a un procedimiento de dos tiempos (3/103 frente a 24/241; 2,9% frente a 10,0%; p = 0,026). El análisis multivariado identificó cinco parámetros enterográficos por tomografía axial computada, incluidos la proliferación fibrograsa mesentérica, el absceso o flegmón intra-abdominal, la fístula entérica, el derrame peritoneal y la dilatación intestinal debido a estenosis como predictores independientes de complicaciones sépticas intra-abdominales (p <0,001). Se construyó un modelo de Nomograma basado en estos cinco parámetros. Un análisis de las características operatorias del receptor identificó una puntuación de cohortes del nomograma de la enterografía por tomografía axial computada de 175 como predictor de complicaciones sépticas intra-abdominales con una sensibilidad del 83,3% y una especificidad del 85,3%. En el estudio prospectivo, los pacientes con puntuación de nomograma enterográfico por tomografía axial computada superior a 175 fueron asignados al grupo en dos tiempos, lo que resultó en una incidencia similar de complicaciones sépticas intra-abdominales en aquellos sometidos a resección intestinal con o sin anastomosis (2/82 vs. 2/34; p = 0,355).LIMITACIONES:Este estudio estuvo limitado por su alcance unicéntrico.CONCLUSIÓN:Los hallazgos enterográficos por tomografía axial computada pré-operatoria pueden predecir ciertos resultados postoperatorios y ayudar a determinar el abordaje quirúrgico en la enfermedad de Crohn. Los pacientes con peores hallazgos intra-abdominales confirmados por enterografía en la tomografía axial computada podrían beneficiarse de la creación de un estoma después de la resección intestinal. Consulte Video Resumen en http://links.lww.com/DCR/B588. (Traducción-Dr Xavier Delgadillo).

Cell compaction is not required for the development of gradient refractive index profiles in the embryonic chick lens.

The development of the eye requires the co-ordinated integration of optical and neural elements to create a system with requisite optics for the given animal. The eye lens has a lamellar structure with gradually varying protein concentrations that increase towards the centre, creating a gradient refractive index or GRIN. This provides enhanced image quality compared to a homogeneous refractive index lens. The development of the GRIN during ocular embryogenesis has not been investigated previously. This study presents measurements using synchrotron X-ray Talbot interferometry and scanning electron microscopy of chick eyes from embryonic day 10: midway through embryonic development to E18: a few days before hatching. The lens GRIN profile is evident from the youngest age measured and increases in magnitude of refractive index at all points as the lens grows. The profile is parabolic along the optic axis and has two distinct regions in the equatorial plane. We postulate that these may be fundamental for the independent central and peripheral processes that contribute to the optimisation of image quality and the development of an eye that is emmetropic. The spatial distributions of the distinct GRIN profile regions match with previous measurements on different fibre cell groups in chick lenses of similar developmental stages. Results suggest that tissue compaction may not be necessary for development of the GRIN in the chick eye lens.

Contributions of shape and stiffness to accommodative loss in the ageing human lens: a finite element model assessment.

Ageing changes to the various components of the accommodative system of the eye lens contribute to the loss of focusing power. The relative contributions of each ageing component, however, are not well defined. This study investigates the contribution of geometric parameters and material properties on accommodation, simulated using models based on human lenses aged 16, 35, and 48 years. Each model was tested using two different sets of material properties and a range of zonular fiber angles and was compared to results from in vivo measurements. The geometries and material parameters of older and younger lens models were interchanged to investigate the role of shape and material on accommodative capacity. Results indicate that geometry has the greater role in accommodation.

Noncoherent Decision Fusion over Fading Hybrid MACs in Wireless Sensor Networks.

In this paper, we consider the problem of decision fusion for noncoherent detection in a wireless sensor network. Novel to the current work is the integration of the hybrid multi-access channel (MAC) in the fusion rule design. We assume that sensors transmit their local binary decisions over a hybrid MAC which is a composite of conventional orthogonal and nonorthogonal MACs. Under Rayleigh fading scenario, we present a likelihood ratio (LR)-based fusion rule, which has been shown to be optimal through theoretical analysis and simulation. However, it requires a large amount of computation, which is not easily implemented in resource-constrained sensor networks. Therefore, three sub-optimal alternatives with low-complexity are proposed, namely the weighed energy detector (WED), the deflection-coefficient-maximization (DCM), and the two-step (TS) rules. We show that when the channel signal-to-noise ratio (SNR) is low, the LR-based fusion rule reduces to the WED rule; at high-channel SNR, it is equivalent to the TS rule; and at moderate-channel SNR, it can be approached closely by the DCM rule. Compared with the conventional orthogonal and nonorthogonal MACs, numerical results show that the hybrid MAC with the proposed fusion rules can improve the detection performance when the channel SNR is medium.

The Effect of Lens Shape, Zonular Insertion and Finite Element Model on Simulated Shape Change of the Eye Lens.

The process of lens shape change in the eye to alter focussing (accommodation) is still not fully understood. Modelling approaches have been used to complement experimental findings in order to determine how constituents in the accommodative process influence the shape change of the lens. An unexplored factor in modelling is the role of the modelling software on the results of simulated shape change. Finite element models were constructed in both Abaqus and Ansys software using biological parameters from measurements of shape and refractive index of two 35-year-old lenses. The effect of zonular insertion on simulated shape change was tested on both 35-year-old lens models and with both types of software. Comparative analysis of shape change, optical power, and stress distributions showed that lens shape and zonular insertion positions affect the results of simulated shape change and that Abaqus and Ansys show differences in their respective models. The effect of the software package used needs to be taken into account when constructing finite element models and deriving conclusions.

In Vivo Biomechanical Measurements of the Cornea.

In early corneal examinations, the relationships between the morphological and biomechanical features of the cornea were unclear. Although consistent links have been demonstrated between the two in certain cases, these are not valid in many diseased states. An accurate assessment of the corneal biomechanical properties is essential for understanding the condition of the cornea. Studies on corneal biomechanics in vivo suggest that clinical problems such as refractive surgery and ectatic corneal disease are closely related to changes in biomechanical parameters. Current techniques are available to assess the mechanical characteristics of the cornea in vivo. Accordingly, various attempts have been expended to obtain the relevant mechanical parameters from different perspectives, using the air-puff method, ultrasound, optical techniques, and finite element analyses. However, a measurement technique that can comprehensively reflect the full mechanical characteristics of the cornea (gold standard) has not yet been developed. We review herein the in vivo measurement techniques used to assess corneal biomechanics, and discuss their advantages and limitations to provide a comprehensive introduction to the current state of technical development to support more accurate clinical decisions.

Arthroscopic Rotator Cuff Repair With Superior Fulcrum Reconstruction Using Autologous Ipsilateral Peroneus Longus Tendon for Irreparable Massive Rotator Cuff Tears.

Rotator cuff tears are still among the serious challenges encountered by sports medicine surgeons. With the development of arthroscopic technology, the treatment options for irreparable massive rotator cuff tears (IMRCTs) have gradually increased, but postoperatively, these options are prone to graft retears, reoperations, infections, revision surgical procedures, and so on. On the basis of studies on the balance of the force couples of the rotator cuff, more scholars believe that when addressing IMRCTs, attention should be paid to the reconstruction of the force couples of the rotator cuff; hence, we developed the superior fulcrum reconstruction technique. This article describes an alternative approach to IMRCT repair with superior fulcrum reconstruction using autologous ipsilateral peroneus longus tendon.

The major influence of anterior and equatorial zonular fibres on the far-to-near accommodation revealed by a 3D pre-stressed model of the anterior eye.

PURPOSE: To explore the synergistic function of the ligaments in eye, the zonular fibres, that mediate change in eye lens shape to allow for focussing over different distances. METHODS: A set of 3D Finite Element models of the anterior eye together with a custom developed pre-stress modelling approach was proposed to simulate vision for distant objects (the unaccommodated state) to vision for near objects (accommodation). One of the five zonular groups was cut off in sequence creating five models with different zonular arrangements, the contribution of each zonular group was analysed by comparing results of each specific zonular-cut model with those from the all-zonules model in terms of lens shape and zonular tensions. RESULTS: In the all-zonular model, the anterior and equatorial zonules carry the highest tensions. In the anterior zonular-cut model, the equatorial zonular tension increases while the posterior zonular tension decreases, resulting in an increase in the change in Central Optical Power (COP). In the equatorial zonular-cut model, both the anterior and posterior zonular tensions increase, causing a decreasing change in COP. The change in COP decreases only slightly in the other models. For vitreous zonular-cut models, little change was seen in either the zonular tension or the change in COP. CONCLUSIONS: The anterior and the equatorial zonular fibres have the major influence on the change in lens optical power, with the anterior zonules having a negative effect and the equatorial zonules contributing a positive effect. The contribution to variations in optical power by the equatorial zonules is much larger than by the posterior zonules.

Design of an Automatically Controlled Multi-Axis Stretching Device for Mechanical Evaluations of the Anterior Eye Segment.

The young eye has an accommodative ability involving lens shape changes to focus over different distances. This function gradually decreases with age, resulting in presbyopia. Greater insights into the mechanical properties of anterior eye structures can improve understanding of the causes of presbyopia. The present study aims to develop a multi-axis stretching device for evaluating the mechanical properties of the intact eye lens. A stretching device integrating the mechanical stretcher, motor, torque sensor and data transmission mechanism was designed and developed by 3D printing. The mechanical stretcher can convert rotation into radial movement, both at constant speeds, according to the spiral of Archimedes. The loading unit equipped with eight jaws can hold the eye sample tightly. The developed device was validated with a spring of known constant and was further tested with anterior porcine eye segments. The validation experiment using the spring resulted in stiffness values close to the theoretical spring constant. Findings from measurements with porcine eye samples indicated that the measured forces are within the ranges reported in the literature. The developed multi-axis stretching device has good repeatability during experiments with similar settings and can be reliably used for mechanical evaluations of the intact eye lens.

Influence of design parameters and capsulorhexis on intraocular lens stabilities: A 3D finite element analysis.

BACKGROUND: Current treatment of cataract widely used in clinics is by removal of the opacified content from the lens capsule which is followed by insertion of an artificial intraocular lens (IOL). The IOL needs to remain stabilized in the capsular bag for the eye to achieve desired optical quality. The present study aims to investigate how different design parameters of the IOL can influence the axial and rotational stabilities of IOLs using Finite Element Analysis. METHODS: Eight designs of IOL with variations in types of optics surface, types of haptics and haptic angulation were constructed using parameters obtained from an online IOL databank (IOLs.eu). Each IOL was subjected to compressional simulations both by two clamps and by a collapsed natural lens capsule with an anterior rhexis. Comparisons were made between the two scenarios on axial displacement, rotation, and distribution of stresses. RESULTS: The clamps compression method set out by ISO does not always produce the same outcome as the in-the-bag analysis. The open-loop IOLs show better axial stability while the closed-loop IOLs show better rotational stability when compressed by two clamps. Simulations of IOL in the capsular bag only demonstrate better rotational stability for closed-loop designs. CONCLUSIONS: The rotational stability of an IOL is largely dependent on its haptic design whilst the axial stability is affected by the appearance of the rhexis to the anterior capsule which has a major influence on designs with a haptic angulation.

Age-Dependent Changes in the Water Content and Optical Power of the In Vivo Mouse Lens Revealed by Multi-Parametric MRI and Optical Modeling.

Purpose: The purpose of this study was to utilize in vivo magnetic resonance imaging (MRI) and optical modeling to investigate how changes in water transport, lens curvature, and gradient refractive index (GRIN) alter the power of the mouse lens as a function of age. Methods: Lenses of male C57BL/6 wild-type mice aged between 3 weeks and 12 months (N = 4 mice per age group) were imaged using a 7T MRI scanner. Measurements of lens shape and the distribution of T2 (water-bound protein ratios) and T1 (free water content) values were extracted from MRI images. T2 values were converted into the refractive index (n) using an age-corrected calibration equation to calculate the GRIN at different ages. GRIN maps and shape parameters were inputted into an optical model to determine ageing effects on lens power and spherical aberration. Results: The mouse lens showed two growth phases. From 3 weeks to 3 months, T2 decreased, GRIN increased, and T1 decreased. This was accompanied by increased lens thickness, volume, and surface radii of curvatures. The refractive power of the lens also increased significantly, and a negative spherical aberration was developed and maintained. Between 6 and 12 months of age, all physiological, geometrical, and optical parameters remained constant, although the lens continued to grow. Conclusions: In the first 3 months, the mouse lens power increased as a result of changes in shape and in the GRIN, the latter driven by the decreased water content of the lens nucleus. Further research into the mechanisms regulating this decrease in mouse lens water could improve our understanding of how lens power changes during emmetropization in the developing human lens.

A single-cell transcriptional landscape of immune cells shows disease-specific changes of T cell and macrophage populations in human achalasia.

Achalasia is a rare motility disorder of the esophagus caused by the gradual degeneration of myenteric neurons. Immune-mediated ganglionitis has been proposed to underlie the loss of myenteric neurons. Here, we measure the immune cell transcriptional profile of paired lower esophageal sphincter (LES) tissue and blood samples in achalasia and controls using single-cell RNA sequencing (scRNA-seq). In achalasia, we identify a pattern of expanded immune cells and a specific transcriptional phenotype, especially in LES tissue. We show C1QC+ macrophages and tissue-resident memory T cells (TRM), especially ZNF683+ CD8+ TRM and XCL1+ CD4+ TRM, are significantly expanded and localized surrounding the myenteric plexus in the LES tissue of achalasia. C1QC+ macrophages are transcriptionally similar to microglia of the central nervous system and have a neurodegenerative dysfunctional phenotype in achalasia. TRM also expresses transcripts of dysregulated immune responses in achalasia. Moreover, inflammation increases with disease progression since immune cells are more activated in type I compared with type II achalasia. Thus, we profile the immune cell transcriptional landscape and identify C1QC+ macrophages and TRM as disease-associated immune cell subsets in achalasia.