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1.
Public Underst Sci ; : 9636625241229415, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38383327

ABSTRACT

A recent wave of studies has diversified science communication by emphasizing gender, race, and disability. In this article, we focus on the understudied lens of religion. Based on an analysis of ultra-Orthodox (Haredi) science journalism and its readership, we identify four main strategies for tailoring science, which we call the four "R"s-removing, reclaiming, remodeling, and rubricating science. By analyzing how science communication is produced by and for a particular religious group, we reveal the diverse ways a religious-sensitive science communication is shaped by community gatekeepers, while also exploring the ethical and epistemological tensions this tailoring entails.

2.
J Cataract Refract Surg ; 46(12): 1588-1595, 2020 12.
Article in English | MEDLINE | ID: mdl-32818347

ABSTRACT

PURPOSE: To determine the ability to differentiate between normal eyes and clinically unaffected eyes of patients with highly asymmetric keratoconus (AKC) using a Scheimpflug/Placido device. SETTING: Tel Aviv Sourasky Medical Center and Enaim Medical Center, Israel. DESIGN: Retrospective case-control. METHODS: Imaging from a combined Scheimpflug/Placido device (Sirius, C.S.O.) was obtained from 26 clinically unaffected eyes of patients with frank keratoconus in the fellow eye, and 166 eyes from 166 patients with bilaterally normal corneal examinations that underwent uneventful corneal refractive surgery with at least 1 year of follow-up. Receiver operating characteristic curves were produced to calculate the area under the curve, sensitivity, and specificity of 60 metrics, and finally a logistic regression modeling was used to determine optimal variables to differentiate populations. RESULTS: The most predictive individual metric able to differentiate between 26 eyes in the case group to 166 eye in the control group was the posterior wall inferior-superior (I-S) ratio, with an receiver operating characteristics (ROC) of 0.862. A combination model of 4 metrics (posterior wall I-S ratio in the central 3 mm, thinnest pachymetry coordinate on the x horizontal axis, posterior asymmetry and asphericity index, corneal volume) yielded an ROC of 0.936, with a sensitivity/specificity pair of 92.3%/87%. Variables related to elevation were not found significant. CONCLUSIONS: Using a combination of metrics from a combined Scheimpflug/Placido device, a practical model for discrimination between clinically normal eyes of patients with highly AKC and normal eyes was constructed. Variables related to pachymetry and posterior cornea asymmetry were the most impactful.


Subject(s)
Keratoconus , Cornea , Corneal Pachymetry , Corneal Topography , Humans , Keratoconus/diagnosis , ROC Curve , Retrospective Studies
3.
J Refract Surg ; 35(11): 721-728, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31710374

ABSTRACT

PURPOSE: To determine the relative impact of contact lens- assisted corneal cross-linking (CACXL) and standard protocol CXL (CXL) on regional corneal stiffness using Brillouin microscopy. METHODS: CXL and CACXL were performed on 30 intact fresh porcine eyes (15 per group). Depth profile of stiffness variation and averaged elastic modulus of anterior, middle, and posterior stroma were determined by Brillouin maps. Corneas were cut into strips to conduct mechanical stress-strain tests after Brillouin microscopy to evaluate stiffness difference between CXL and CACXL. Each eye served as its own control. RESULTS: CXL had a greater impact on corneal stiffness, with a maximum increase of 5.74% compared to 3.99% for CACXL (P < .001). CXL increased longitudinal modulus by 7.8% in the anterior, 1.7% in the middle, and -0.7% in the posterior regions compared to CACXL, which increased longitudinal modulus by 5.5% in the anterior (P < .001), 1.2% in the middle (P = .15), and -0.4% in the posterior regions (P = .60). Mechanical stress-strain tests showed that at 10% strain averaged Young's modulus was 5 MPa for CXL and 2.97 MPa for CACXL (P < .001). CONCLUSIONS: Both CACXL and standard protocol CXL induced significant corneal stiffening primarily concentrated in the anterior cornea. CACXL leads to less stiffening compared with CXL. An attenuated but continuous stiffening effect can be observed through the whole cornea for both CACXL and CXL, although CACXL has a smaller stiffness gradient. [J Refract Surg. 2019;35(11):721-728.].


Subject(s)
Collagen/pharmacology , Contact Lenses , Cornea/physiopathology , Corneal Diseases/drug therapy , Cross-Linking Reagents/pharmacology , Photochemotherapy/methods , Riboflavin/pharmacology , Animals , Cornea/diagnostic imaging , Corneal Diseases/pathology , Corneal Diseases/physiopathology , Disease Models, Animal , Elasticity , Microscopy/methods , Photosensitizing Agents/pharmacology , Swine
4.
J Cataract Refract Surg ; 45(7): 985-991, 2019 07.
Article in English | MEDLINE | ID: mdl-31029477

ABSTRACT

PURPOSE: To compare the difference and agreement of corneal higher-order aberrations (HOAs) in keratoconic eyes using Scheimpflug and dual Scheimpflug-Placido imaging systems. SETTING: Emory University, Atlanta, Georgia, and the University of Southern California, Los Angeles, California, USA. DESIGN: Retrospective between-devices reliability and agreement study. METHODS: Patients diagnosed with keratoconus were evaluated sequentially by Scheimpflug and dual Scheimpflug-Placido devices. Differences, correlations, and agreement between values for total root mean square (RMS), trefoil, coma, and spherical aberration were analyzed, and Bland-Altman plots were generated. RESULTS: Fifty eyes from 50 patients (31 men, 19 women) were evaluated. Trefoil at 30 degrees, spherical aberration, and total RMS were significantly different between groups (P < .05), whereas trefoil at 0 degrees and total coma values were not statistically different. There was a weak positive correlation between devices for trefoil at 0 degrees (r = 0.228), and a moderate positive correlation for trefoil at 30 degrees (r = 0.473), horizontal coma (r = 0.430), and for total corneal RMS (r = 0.637). Vertical coma (r = 0.816) and spherical aberration (r = 0.874) showed a strong positive correlation. The 95% limits of agreement (LoA) for absolute values were 1.963 µm for trefoil at 30 degrees, 2.449 µm for trefoil at 0 degrees, 3.530 µm for horizontal coma, 2.145 µm for vertical coma, 1.242 µm for spherical aberration, and 10.527 µm for RMS. CONCLUSION: Significant differences were found between measurements of corneal HOAs generated by Scheimpflug and dual Scheimpflug-Placido devices in patients with keratoconus, with generally limited correlations and wide LoA. HOAs measurements from these devices should not be considered equivalent.


Subject(s)
Cornea/pathology , Corneal Topography/methods , Corneal Wavefront Aberration/diagnosis , Keratoconus/diagnosis , Refraction, Ocular/physiology , Adult , Corneal Wavefront Aberration/physiopathology , Female , Humans , Keratoconus/physiopathology , Male , Reproducibility of Results , Retrospective Studies
5.
J Cataract Refract Surg ; 45(4): 490-494, 2019 04.
Article in English | MEDLINE | ID: mdl-30713018

ABSTRACT

PURPOSE: To compare higher order aberrations (HOAs) in normal eyes between a Scheimpflug imaging system (Pentacam HR) and dual Scheimpflug-Placido imaging system (Galilei G4). SETTING: Emory University, Atlanta, Georgia, and the University of Southern California, Los Angeles, USA. DESIGN: Retrospective case series. METHODS: Eyes screened for refractive surgery were evaluated sequentially using a Scheimpflug device and a dual Scheimpflug-Placido device. Differences, correlations, and agreement between values for total root mean square (RMS), trefoil, coma, and spherical aberration were analyzed, and Bland-Altman plots were generated. RESULTS: One hundred five eyes of 105 patients (44 men, 61 women) were evaluated. Total RMS, coma, and trefoil were significantly different between groups (all P < .001), while spherical aberration values were not. There was moderate correlation between devices for trefoil (r = 0.475 to 0.652), coma (r = 0.574 to 0.651), and spherical aberration (r = 0.483) and a strong correlation for total cornea RMS (r = 0.817). There was no directional bias between groups. The 95% limits of agreement for absolute values was 0.039 µm for trefoil at 30 degrees, 0.405 µm for trefoil at 0 degree, 0.553 µm for horizontal coma, 0.545 µm for vertical coma, 0.318 µm for spherical aberration, and 0.617 µm for RMS. CONCLUSIONS: A Scheimpflug imaging device and dual Scheimpflug-Placido imaging device generated statistically different values for total cornea HOAs; however, the correlation between devices was moderate to strong and there was reasonable agreement in all measures for normal eyes. Based on these findings, the devices appear functionally equivalent for clinical use, although caution is warranted for outcomes-based research protocols that report HOAs.


Subject(s)
Corneal Wavefront Aberration/diagnosis , Diagnostic Imaging/methods , Diagnostic Techniques, Ophthalmological/instrumentation , Adult , Female , Healthy Volunteers , Humans , Keratomileusis, Laser In Situ/methods , Lasers, Excimer/therapeutic use , Male , Middle Aged , Photography/instrumentation , Refraction, Ocular/physiology , Retrospective Studies , Visual Acuity/physiology , Young Adult
6.
Am J Ophthalmol ; 201: 46-53, 2019 05.
Article in English | MEDLINE | ID: mdl-30721688

ABSTRACT

PURPOSE: To identify the best metrics or combination of metrics that provide the highest predictive power between normal eyes and the clinically unaffected eye of patients with highly asymmetric keratoconus using data from a Dual Scheimpflug/Placido device. DESIGN: Retrospective case-control study. METHODS: Combined Dual Scheimpflug/Placido imaging was obtained from the Galilei G4 device (Ziemer Ophthalmic Systems AG, Port, Switzerland) in 31 clinically unaffected eyes with highly asymmetric keratoconus and 178 eyes from 178 patients with bilaterally normal corneal examinations that underwent uneventful LASIK with at least 1 year follow-up. Receiver operating characteristic (ROC) curves were generated to determine area under the curve (AUC), sensitivity, and specificity for 87 metrics, and logistic regression modeling was used to determine optimal variable combinations. RESULTS: No individual metric achieved an AUC greater than 0.79. A combined model consisting of 9 metrics yielded an AUC of 0.96, with 90.3% sensitivity and 92.6% specificity. Among those 9 metrics included, 5 related to corneal pachymetry: Opposite Sector Index and Anterior Height BFS Z from the anterior surface, Asphericity and Asymmetry Index, Posterior Height BFS Z, and Posterior Height BFS X from the posterior surface. The strongest variable in the model was the thinnest point location on the horizontal (x) axis. CONCLUSION: While individual metrics performed poorly, using a combination of metrics from the combined Dual Scheimpflug/Placido device provided a useful model for differentiating normal corneas from the clinically normal eyes of patients with highly asymmetric keratoconus. Pachymetry values were the most impactful metrics.


Subject(s)
Cornea/diagnostic imaging , Corneal Topography/methods , Keratoconus/diagnosis , Photography/instrumentation , Tomography/instrumentation , Adolescent , Adult , Aged , Area Under Curve , Case-Control Studies , Female , Humans , Keratoconus/surgery , Keratomileusis, Laser In Situ/methods , Lasers, Excimer/therapeutic use , Male , Middle Aged , ROC Curve , Retrospective Studies , Young Adult
7.
J Refract Surg ; 34(10): 664-670, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-30296327

ABSTRACT

PURPOSE: To compare posterior corneal features and their discriminating power for differentiating normal corneas from subclinical keratoconus using the Placido dual-Scheimpflug analyzer. METHODS: Patients were retrospectively included in the study. The preoperative normal right eyes of 79 patients imaged with a Placido dual-Scheimpflug system and with a stable postoperative LASIK follow-up of a minimum of 36 months were included in the normal group and were compared to 39 contralateral topographically normal eyes with clinically evident keratoconus in the fellow eye. The posterior surface variables measured were categorized according to the feature of the corneal shape they were characterizing (curvature, elevation, asymmetry, and eccentricity) and compared between the two groups using the Student's two-sample t test. The discriminating ability of the posterior surface variables was compared by receiver operator characteristics curves. RESULTS: Variables that related to asymmetry and elevation of the posterior surface were statistically significantly different between groups (P < .05), whereas eccentricity and curvature-related parameters were not. Receiver operator characteristics curves analysis showed that the maximum posterior elevation over the best-fit toric and aspheric surface reference shape had the highest discriminating ability for distinguishing normal corneas from subclinical keratoconus, with an area under the curve of 0.877, followed by the asphericity asymmetry index, with an area under the curve of 0.871, and posterior inferior-superior value, with an area under the curve of 0.851. CONCLUSIONS: Posterior cornea measured with a dual-Scheimpflug analyzer provides useful parameters for differentiating normal corneas from subclinical keratoconus. Of the posterior surface parameters, asymmetry and elevation seem to be the most sensitive shape modifications for differentiating both populations. [J Refract Surg. 2018;34(10):664-670.].


Subject(s)
Cornea/anatomy & histology , Cornea/pathology , Diagnostic Techniques, Ophthalmological , Keratoconus/diagnosis , Adult , Corneal Pachymetry , Corneal Topography , Dilatation, Pathologic/diagnosis , Dilatation, Pathologic/surgery , Female , Humans , Keratoconus/surgery , Keratomileusis, Laser In Situ , Lasers, Excimer/therapeutic use , Male , ROC Curve , Retrospective Studies , Sensitivity and Specificity , Young Adult
8.
Curr Opin Ophthalmol ; 29(4): 306-312, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29708926

ABSTRACT

PURPOSE OF REVIEW: To review current concepts regarding the mechanisms of postoperative pain after photorefractive keratectomy (PRK) and review available treatment options. RECENT FINDINGS: Many clinical studies have established the safety and efficacy of different topical and systematic therapeutic agents and techniques for the treatment of postoperative pain after PRK, especially topical nonsteroidal anti inflammatory agents and oral nonsteroidal and narcotic medications. New therapeutic agents and techniques are continuously studied, introducing new agents and comparing teh efficacy of different regimens. Postoperative pain severity varies widely between patients, and no single strategy has been proven best for acute pain management. SUMMARY: To date, the literature supports the use of topical agents such as nonsteroidal anti-inflammatory medications (NSAIDs) and diluted topical anesthetics in combination with oral agents such as opiates and NSAIDs for acute pain management. The use of local agents and techniques is preferred due to their less significant side effect profile. The use of systemic opiate agents is reserved for breakthrough pain.


Subject(s)
Eye Pain/drug therapy , Pain Management/methods , Pain, Postoperative/drug therapy , Photorefractive Keratectomy/adverse effects , Analgesics, Opioid/administration & dosage , Anesthetics, Local/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Eye Pain/etiology , Humans , Myopia/surgery , Pain, Postoperative/etiology
9.
Gynecol Endocrinol ; 20(4): 185-7, 2005 Apr.
Article in English | MEDLINE | ID: mdl-16019359

ABSTRACT

OBJECTIVE: To determine the levels of serum P-selectin in patients undergoing controlled ovarian hyperstimulation (COH) cycles with urinary (uGn) versus recombinant gonadotropins (rGn) and their possible correlation with COH variables. METHODS: This study was carried out in a large university-based infertility and in vitro fertilization unit. A total of 14 consecutive patients underwent our routine COH protocol for unexplained infertility with either uGn or rGn. Blood was drawn three times during the COH cycle: on day 2 or 3 of the menstrual cycle and before gonadotropin treatment (day-0); on the day of or prior to human chorionic gonadotropin (hCG) administration (day-hCG); and on the day of ovulation (day-OVU). Levels of sex steroids and serum P-selectin were compared among the three time points between the uGn and rGn subgroups. P-selectin was measured with a commercial quantitative sandwich immunoassay technique. RESULTS: In both Gn subgroups, there was a non-significant increase in P-selectin level between day-hCG and day-0. In the rGN subgroup, no significant difference was observed in P-selectin levels between day-OVU and day-hCG. In the uGn subgroup, P-selectin levels were significantly lower in day-OVU as compared to day-hCG (p < 0.04) and day-0 (p < 0.04). No differences were noted between the uGn and rGn subgroups in patient age, number of gonadotropin ampules used or estradiol and progesterone levels during the COH cycle or P-selectin on day-0 or day-hCG. However, on day-OVU, P-selectin levels were significantly lower in the uGn than the rGn subroups (p < 0.01). CONCLUSION: The increase in serum P-selectin level during COH until the peak of estradiol level was significantly attenuated after hCG administration in patients pretreated with uGn, but not rGN. It would therefore be prudent in patients at risk of developing thromboembolism undergoing COH to use uGN rather than rGN in order to attenuate platelet activation.


Subject(s)
Chorionic Gonadotropin/pharmacology , Ovulation Induction/methods , P-Selectin/blood , Adult , Estradiol/blood , Female , Humans , Longitudinal Studies , Progesterone/blood , Prospective Studies , Recombinant Proteins/pharmacology , Statistics, Nonparametric
10.
J Org Chem ; 61(23): 8277-8284, 1996 Nov 15.
Article in English | MEDLINE | ID: mdl-11667816

ABSTRACT

A conformational search procedure (HUNTER), in combination with the MM3(92) program, was used for the exploration of the conformational hypersurface of alkyl-substituted cyclohexanes and for the calculation of their chair/twist-boat (TB) energy gap. The systems studied were conformationally unconstrained polyalkylcyclohexanes (alkyl = methyl, ethyl, isopropyl, and tert-butyl) possessing either geminal and/or vicinal arrangements of the alkyl groups, but differing in the number of alkyl substituents and in their relative disposition (i.e., cis or trans). The calculations indicate that in 1,1,3,3,5,5-hexaisopropylcyclohexane the TB is the lowest energy form. Modification of the cis,trans relationship of vicinal alkyl groups changes the chair/TB energy gap, and in the minimum energy conformation of cis,trans,trans-1,2,3,4-tetraisopropylcyclohexane (23c) and cis,syn,cis-1,2,4,5-tetraisopropylcyclohexane (31c) the cyclohexyl ring adopts a TB conformation. The tetrasubstituted systems cis,syn,cis-1,2-diisopropyl-3,4-dimethylcyclohexane (46), cis,syn,cis-1,4-diisopropyl-2,5-dimethyl-cyclohexane (47), and cis,trans,trans-1,2-diisopropyl-3,4-dimethylcyclohexane (41) are the least crowded monocyclic unconstrained cyclohexanes found in which the TB conformation is of lower energy than the chair form. The present study indicates that two methyls and two isopropyl substituents are sufficient for stabilizing the TB form of a cyclohexyl ring relative to the chair form.

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