bluuebunny/crossref_metadata_2025 huggingface dataset:
Laboratory Measurements of X-Ray Emission from Highly Charged Argon Ions
Authors: Bulbul Esra , Foster Adam , Brown Gregory V. , Bautz Mark W. , Beiersdorfer Peter , Hell Natalie , Kilbourne Caroline , Kraft Ralph , Kelley Richard , Leutenegger Maurice A. , Miller Eric D. , Porter F. Scott , Smith Randall K.
Published: December 2018

Uncertainties in atomic models will introduce noticeable additional systematics in calculating the flux of weak dielectronic recombination (DR) satellite lines, affecting the detection and flux measurements of other weak spectral lines. One important example is the Ar xvii Heβ DR, which is expected to be present in emission from the hot intracluster medium of galaxy clusters and could impact measurements of the flux of the 3.5 keV line that has been suggested as a secondary emission from a dark matter interaction. We perform a set of experiments using the Lawrence Livermore National Laboratory’s electron beam ion trap (EBIT-I) and the X-ray Spectrometer quantum calorimeter (XRS/EBIT) to test the Ar xvii Heβ DR origin of the 3.5 keV line. We measured the X-ray emission following resonant DR onto helium-like and lithium-like Argon using EBIT-I’s Maxwellian simulator mode at a simulated electron temperature of T

e
 = 1.74 keV. The measured flux of the Ar xvii Heβ DR lined is too weak to account for the flux in the 3.5 keV line, assuming reasonable plasma parameters. We, therefore, rule out Ar xvii Heβ DR as a significant contributor to the 3.5 keV line. A comprehensive comparison between the atomic theory and the EBIT experiment results is also provided.
SCORCH. II. Radiation-hydrodynamic Simulations of Reionization with Varying Radiation Escape Fractions
Authors: Doussot Aristide , Trac Hy , Cen Renyue
Published: December 2018

In the Simulations and Constructions of the Reionization of Cosmic Hydrogen project, we present new radiation-hydrodynamic simulations with updated high-redshift galaxy populations and varying radiation escape fractions. The simulations are designed to have fixed Thomson optical depth τ ≈ 0.06, consistent with recent Planck observations, and similar midpoints of reionization 7.5 ≲ z ≲ 8.0, but with different ionization histories. The galaxy luminosity functions and ionizing photon production rates in our model are in good agreement with recent HST observations. Adopting a power-law form for the radiation escape fraction

, we simulate the cases for a
8 = 0, 1, and 2 and find a
8 ≲ 2 in order to end reionization in the range of 5.5 ≲ z ≲ 6.5 to be consistent with Lyα forest observations. At fixed τ and as the power-law slope a
8 increases, the reionization process starts earlier but ends later with a longer duration Δz and the decreased redshift asymmetry Az. We find a range of durations 3.9 ≲ Δz ≲ 4.6 that is currently in tension with the upper limit Δz < 2.8 inferred from a recent joint analysis of Planck and South Pole Telescope observations.
Impacts of EUV Wavefronts on Coronal Structures in Homologous Coronal Mass Ejections
Authors: Liu Rui , Wang Yuming , Lee Jeongwoo , Shen Chenglong
Published: December 2018

Large-scale propagating fronts are frequently observed during solar eruptions, yet whether or not they are waves is an open question, partly because the propagation is modulated by coronal structures, whose magnetic fields we still cannot measure. However, when a front impacts coronal structures, an opportunity arises for us to look into the magnetic properties of both interacting parties in the low-β corona. Here we studied large-scale EUV fronts accompanying three coronal mass ejections (CMEs), each originating from a kinking rope-like structure in the NOAA active region (AR) 12371. These eruptions were homologous and the surrounding coronal structures remained stationary. Hence we treated the events as one observed from three different viewing angles, and found that the primary front directly associated with the CME consistently transmits through (1) a polar coronal hole, (2) the ends of a crescent-shaped equatorial coronal hole, leaving a stationary front outlining its AR-facing boundary, and (3) two quiescent filaments, producing slow and diffuse secondary fronts. The primary front also propagates along an arcade of coronal loops and slows down due to foreshortening at the far side, where local plasma heating is indicated by an enhancement in 211 Å (Fe xiv) but a dimming in 193 Å (Fe xii) and 171 Å (Fe ix). The strength of coronal magnetic field is therefore estimated to be ∼2 G in the polar coronal hole and ∼4 G in the coronal arcade neighboring the AR. These observations substantiate the wave nature of the primary front and shed new light on slow fronts.
Wavefront-guided LASIK for Myopia Using the LADAR CustomCornea and the VISX CustomVue
Authors: Awwad Shady T , Bowman R Wayne , Cavanagh H Dwight , McCulley James P
Published: December 2018

ABSTRACT

PURPOSE: To evaluate the objective and subjective visual outcomes and refractive results of wavefrontguided LASIK with LADAR CustomCornea and VISX CustomVue.

METHODS: This prospective randomized single-institution multisurgeon study comprised 100 eyes of 58 patients (50 eyes on each laser platform). Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and manifest refraction were measured postoperatively at 1 day, 1 week, 1 month, and 3 months. Contrast sensitivity, higher order aberrations measurement, and a subjective vision questionnaire were performed preoperatively and at 3 months.

RESULTS: Preoperatively, the CustomCornea group had a mean manifest sphere of -3.58±1.61 diopters (D) (range: -0.50 to -7.25 D), cylinder of +0.64±0.45 D (range: 0 to +1.75 D), and manifest refractive spherical equivalent (MRSE) of -3.26±1.56 D. The CustomVue group had a manifest sphere of -4.00±1.69 D (range: -1.50 to -7.50 D), cylinder of +0.60±0.52 D (range: 0 to +2.00 D), and MRSE of -3.70±1.64 D. At 3 months, 94% of CustomCornea eyes and 84% of CustomVue eyes had UCVA ≥20/20 (P= .20). Twentyfour percent of CustomVue eyes and 22% of CustomCornea eyes gained 1 line of BSCVA. In both groups, 96% of eyes were within 0.50 D of emmetropia. Mean CustomCornea glare contrast sensitivity improved (P= .04) whereas more eyes improved than worsened in both groups. Spherical aberration and total higher order aberrations increased, and trefoil decreased in both groups. A decrease in coma was noted in 70% of CustomCornea eyes.

CONCLUSIONS: Wavefront-guided LASIK with both platforms is safe, effective, and delivers excellent visual results. CustomCornea improves contrast sensitivity under glare conditions. [J Refract Surg. 2007;23:26-38.]
Optical Analysis of PresbyLASIK Treatment By a Light Propagation Algorithm
Authors: Ortiz Dolores , Alió Jorge L , Illueca Carlos , Mas David , Sala Esperanza , Pérez Jorge , Espinosa J
Published: December 2018

ABSTRACT

PURPOSE: To evaluate the changes in the optical quality of corneas of hyperopic patients operated using central multifocal presbyLASIK treatment through the study of light patterns around the retinal plane.

METHODS: This study included eight hyperopic eyes that underwent central presbyLASIK surgery with Presby-one software using an H. Eye Tech Technovision excimer laser platform. Mean patient age was 57 years. Mean preoperative spherical equivalent refraction was 1.28±0.87 diopters (D). Mean distance decimal visual acuity with correction was 1.02±0.13 and without correction was 0.37±0.15. The optical quality was characterized by the Strehl ratio, the spot size on the retina, and objective decimal visual acuity calculated based on measured corneal topography using Fresnel propagation algorithm based on a realistic eye model.

RESULTS: The postoperative spherical equivalent refraction was -0.55±0.48 D. The distance decimal visual acuity with correction was 0.94 and without correction was 0.70. The pseudoaccommodation range was 1.60±0.40 D. A good Pearson correlation coefficient was obtained (r
p 2
=0.86) for the linear fit between the real and calculated decimal visual acuity for the eight eyes. The Strehl ratio value on the retinal plane increased after the surgery by a mean factor of 4.7.

CONCLUSIONS: With a complete characterization of the eye and a complete propagation algorithm (that takes into account all refractive surfaces in the eye at the same time), it is possible to evaluate the optical quality in eyes of patients who have undergone central presbyLASIK treatment. [J Refract Surg. 2007;23:39-44.]
Phototherapeutic Keratectomy for Epithelial Irregular Astigmatism: An Emphasis on Map-Dot-Fingerprint Degeneration
Authors: Zalentein Waldir Neira , Holopainen Juha M , Tervo Timo M T
Published: December 2018

ABSTRACT

PURPOSE: To study the changes in irregular astigmatism in patients with recurrent corneal erosion syndrome due to map-dot-fingerprint degeneration and to demonstrate that both symptomatic and asymptomatic map-dot-fingerprint degeneration/recurrent corneal erosion syndrome may be related to irregular astigmatism, which can effectively be corrected by phototherapeutic keratectomy (PTK) or standard spherical photorefractive keratectomy (PRK).

METHODS: Eleven eyes with irregular astigmatism related to map-dot-fingerprint degeneration/recurrent corneal erosion syndrome with and without changes at the slit-lamp microscope were treated with PTK or spherical PRK, which was performed with a VISX S2 or S4 excimer laser. All eyes underwent videokeratography performed pre- and postoperatively using either the Tomey TMS-2N Topographic Modeling System or EyeSys Technologies Corneal Analysis System 2000.

RESULTS: Mean pre- and postoperative best spectacle-corrected visual acuity (BSCVA) was -0.18±0.14 logMAR and 0.04±0.04 logMAR, respectively. This improvement in BSCVA was statistically significant. The mean gain in Snellen lines was 2.4±2.1. Preoperative corneal videokeratography showed irregular astigmatism with an elevation pattern that was corrected in all eyes despite the fact that no astigmatic photorefractive correction was performed.

CONCLUSIONS: Following PTK, eyes with irregular astigmatism related to map-dot-fingerprint degeneration showed significant improvement in BSCVA and correction of irregular astigmatism as revealed by videokeratography. This study shows that irregular astigmatism can be exclusively of epithelial origin and in some eyes abnormal corneal epithelium may create optical aberrations. This possibility should be taken into account when, for example, wavefront-guided stromal photoablation procedures are being planned. [J Refract Surg. 2007;23:50-57.]
Femtosecond Laser Keratome Creation of Partial Thickness Donor Corneal Buttons for Lamellar Keratoplasty
Authors: Sarayba Melvin A , Maguen Ezra , Salz James , Rabinowitz Yaron , lgnacio Teresa S
Published: December 2018

ABSTRACT

PURPOSE: To evaluate the thickness and diameter accuracy of the IntraLase femtosecond laser in harvesting corneal discs for lamellar keratoplasty. The stromal bed quality of resected corneas was evaluated by scanning electron microscopy.

METHODS: Two IntraLase units were used to create corneal discs at 225-, 300-, 400-, and 500-µm thickness settings and 7-, 8-, 8.5-, and 9-mm diameter settings (n=28). Achieved thickness was measured using a digital caliper and achieved diameter was measured using imaging software. Samples were preserved and processed for scanning electron microscopy to observe stromal bed quality.

RESULTS: On both units, the mean deviation from attempted thickness was -9.5±8.6 µm (range: +6 to -28 µm). All of the obtained corneal discs were circular (horizontal versus vertical diameters, P>.05). The raster pattern produced a smoother stromal bed compared to the spiral pattern.

CONCLUSIONS: The IntraLase femtosecond laser keratome provides depth and diameter accuracy even at increased depth settings. Stromal bed was smooth with the raster pattern and can further be smoothed by excimer phototherapeutic keratectomy treatment. Femtosecond laser lamellar keratoplasty is a promising procedure and clinical data are needed to determine effectiveness. [J Refract Surg. 2007;23:58-65.]
Sectorial and Annular Quantitative Area Pachymetry With the Orbscan II
Authors: Arce Carlos G , Martiz Jaime , Aizamora Juan B , Schor Paulo , Campos Mauro S Q
Published: December 2018

ABSTRACT

PURPOSE: To present a new application of quantitative area pachymetry of the cornea.

METHODS: Sectorial quantitative area pachymetry of small corneal zones located at the center and surrounding areas is possible by means of the statistical analysis device and tools menu of Orbscan II (Bausch & Lomb).

RESULTS: Average pachymetry of 1 central zone and 12 small zones around the center may be shown in the pachymetry map by simply formatting the system. Average pachymetry, standard deviation, rate of thickness variation (slope), and volume of analyzed annular corneal zone can also be automatically shown in a data window. The examination results can be printed and kept on record.

CONCLUSIONS: The method is simple and descriptive. This type of preoperative evaluation may guide the manual or laser preparation of channels for intracorneal segments and the corneal trephination for lamellar or penetrating keratoplasty. [J Refract Surg. 2007;23:89-92.]
Biomechanical Modeling of Corneal Ectasia
Authors: Dupps William J
Published: December 2018

This article has been amended to include a factual correction. An error was identified subsequent to its original printing (J Refract Surg. 2005;21:186-190), which was acknowledged in an erratum printed in the January 2007 issue of the Journal (J Refract Surg. 2007;23:9). The print article and its erratum remain the version of record.
Postoperative Pain Following Epi-LASIK, LASEK, and PRK for Myopia
Authors: O'Doherty Maeve , Kirwan Caitriona , O'Keeffe Michael , O'Doherty John
Published: December 2018

ABSTRACT

PURPOSE: To compare mechanical epithelial separation using the epi-LASIK technique with alcohol assisted separation (LASEK).

METHODS: Patients deemed suitable for surface ablation were randomized to receive epi-LASIK in one eye and LASEK in the other eye. If epi-LASIK failed, the procedure was converted to photorefractive keratectomy (PRK), forming the third comparison group. The outcome measures were postoperative pain, vision, refraction, and haze. Patients were followed for 3 months.

RESULTS: Fifty-seven patients (95 eyes) were included in this study (38 epi-LASIK, 19 PRK, and 38 LASEK eyes). There was a 33% rate of conversion from intended epi-LASIK to PRK. Epi-LASIK patients were found to have significantly less pain in the first few hours after surgery but at 4 hours all patients had the same levels of pain, which improved to minimal or no pain at 24 hours. No significant difference was noted among groups for vision, refractive error, and haze; however, epi-LASIK patients had the best day 1 visual acuity.

CONCLUSIONS: Epi-LASIK offers comparable visual and refractive results to other surface ablation techniques with lower levels of postoperative pain only for the first 2 hours. However, there was a high rate of flap failure and conversion to PRK. [J Refract Surg. 2007;23:133-138.]
Potentially Accommodating 1CU Intraocular Lens: 1-year Results in 553 Eyes and Literature Review
Authors: Uthoff Detlef , Gulati Amit , Hepper Daniel , Holland Detlef
Published: December 2018

ABSTRACT

PURPOSE: To investigate the advantages, clinical outcomes, and safety after implantation of the ICU (HumanOptics AG) optic shift intraocular lens (IOL) in comparison with a conventional monofocal IOL.

METHODS: In a prospective non-randomized study, 553 eyes implanted with the ICU IOL were examined. In a control group, a monofocal posterior chamber IOL (MCTE, Dr Schmidt) was implanted in 219 eyes. Follow-up was performed at 1, 6, and 12 months postoperatively. The clinical effect for near visual acuity was evaluated by subjective measurements using an accommodometer, defocusing curve, and Nieden charts.

RESULTS: No significant differences were noted in distance best spectacle-corrected visual acuity (BSCVA) between groups. Average near visual acuity with distance BSCVA for the ICU was 0.41 and 0.35 for the control group. The difference in the accommodation response between both groups measured with the accommodometer was 11 cm (P<.01). The refraction tolerance for the ICU was 0.25 D whereas the MCTE revealed no refraction tolerance (P<.01). Decentration and tilting of the ICU resulted in explantation of three IOLs.

CONCLUSIONS: The 1CU indicates a minor statistical advantage of half a reading step towards monofocal IOLs measured with subjective methods in near point, defocusing curve, and near visual acuity with distance BSCVA. This could be due to Pseudophakie accommodation by the optic shift mechanism or a result of additional Pseudophakic pseudoaccommodation. The accommodative effect of the ICU differed from patient to patient and was not predictable. [J Refract Surg. 2007;23:159-171.]
Topographic Centration of Ablation After LASIK for Myopia Using the CustomVue VISX S4 Excimer Laser
Authors: Ou Judy I , Manche Edward E
Published: December 2018

ABSTRACT

PURPOSE: To determine the ablation centration, efficacy, predictability, and safety of CustomVue LASIK using the VISX S4 excimer laser for the treatment of myopia and myopic astigmatism.

METHODS: A retrospective review of 20 myopic eyes of 12 patients treated with LASIK CustomVue VISX S4 was conducted. Corneal topography was used to determine ablation centration. Primary outcome variables including manifest refraction, best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), and complications were evaluated at 3 months postoperatively.

RESULTS: Mean decentration (from ablation zone to entrance pupil) was 0.23±0.08 mm at 3 months postoperatively. No eyes were decentered >0.5 mm. Preoperatively, the mean spherical equivalent refraction was -4.81+1.39 diopters (D) (range: -6.75 to -2.25 D). At 3 months postoperatively, mean spherical equivalent refraction was -0.63±0.25 D (range: -2.00 to 0.25 D). Nineteen (95%) of 20 eyes had UCVA of 20/40 and 16 (80%) of 20 eyes had UCVA of 20/20 at 3 months postoperatively. Fourteen (70%) eyes were within ±0.50 D and 18 (90%) eyes were within ±1.00 D of emmetropia. No eye lost >1 line of BSCVA.

CONCLUSIONS: Wavefront-guided LASIK using the CustomVue VISX S4 for myopic eyes results in minimal decentration ablation and effective, predictable, and safe visual outcomes. [J Refract Surg. 2007;23:193-197.]
Higher Order Aberrations and Relative Risk of Symptoms After LASIK
Authors: Sharma Munish , Wachler Brian S Boxer , Chan Colin C K
Published: December 2018

ABSTRACT

PURPOSE: To understand what level of higher order aberrations increases the relative risk of visual symptoms in patients after myopic LASIK.

METHODS: This study was a retrospective comparative analysis of 103 eyes of 62 patients divided in two groups, matched for age, gender, pupil size, and spherical equivalent refraction. The symptomatic group comprised 36 eyes of 24 patients after conventional LASIK with different laser systems evaluated in our referral clinic and the asymptomatic control group consisted of 67 eyes of 38 patients following LADARVision CustomCornea wavefront LASIK. Comparative analysis was performed for uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), contrast sensitivity, refractive cylinder, and higher order aberrations. Wavefront analysis was performed with the LADARWave aberrometer at 6.5-mm analysis for all eyes.

RESULTS: Blurring of vision was the most common symptom (41.6%) followed by double image (19.4%), halo (16.7%), and fluctuation in vision (13.9%) in symptomatic patients. A statistically significant difference was noted in UCVA (P=. 001), BSCVA (P=OOl), contrast sensitivity (P<.001), and manifest cylinder (P=OOl) in the two groups. The percentage difference between the symptomatic and control group mean root-mean-square (RMS) values ranged from 157% to 206% or 1.57 to 2.06 times greater.

CONCLUSIONS: Patients with visual symptoms after LASIK have significantly lower visual acuity and contrast sensitivity and higher mean RMS values for higher order aberrations than patients without symptoms. Rootmean-square values of greater than two times the normal after-LASIK population for any given laser platform may increase the relative risk of symptoms. [J Refract Surg. 2007;23:252-256.]
Astigmatism and the Impact of Relaxing Incisions After Penetrating Keratoplasty
Authors: Claesson Margareta , Armitage W John
Published: December 2018

ABSTRACT

PURPOSE: To determine the impact of relaxing incisions for correcting postoperative astigmatism following penetrating keratoplasty.

METHODS: Data were collected through the Swedish Corneal Transplant Register. Of the 1161 grafts with complete 2-year follow-up, 131 underwent relaxing incisions. Stepwise multiple regression was used to determine the factors that influenced the extent of astigmatism in diopters (D) (square root transformed). The change in astigmatism brought about by relaxing incisions was evaluated both by subtraction (ie, ignoring angle) and vector analysis.

RESULTS: The overall mean astigmatism was 4.56 D (95% confidence interval [Cl]: 4.40-4.73, n=1161). The final regression model explained only a small proportion of the overall variability of the data (<5%). There was a slight increase in postoperative astigmatism with recipient age (P=. 025), and two of the seven participating clinics achieved lower levels of astigmatism (P=OOl and P=. 036, respectively). In patients who underwent relaxing incisions, astigmatism was reduced from 8.40 D (95% Cl: 8.0-9.0, n=131) to 3.80 D (95% Cl: 3.54.3). The mean difference by subtraction was 4.50 D (95% Cl: 4.0-5.0, P<.001, paired t test). Vector analysis showed the overall reduction of astigmatism due to surgery to be 7.90 D (95% Cl: 7.2-8.7). Compared with grafts with no refractive surgery, a trend was noted that suggested corrected visual acuity was improved following relaxing incisions.

CONCLUSIONS: Relaxing incisions were found to be a safe and effective method for reducing postoperative astigmatism and may improve visual acuity. [J Refract Surg. 2007;23:284-289.]
A Comparative Confocal Microscopy Analysis After LASIK With the IntraLase Femtosecond Laser vs Hansatome Microkeratome
Authors: Ramírez Manuel , Hernández-Quintela Everardo , Naranjo-Tackman Ramón
Published: December 2018

ABSTRACT

PURPOSE: To evaluate and compare confocal microscopy findings between a femtosecond laser and a mechanical microkeratome.

METHODS: Eighteen eyes of nine patients underwent LASIK. Corneal flaps were created with the femtosecond laser in the right eyes and a mechanical microkeratome in the left eyes. The corneal flap interface was analyzed in all eyes with a confocal microscope at 1 week and 1 month postoperatively.

RESULTS: All eyes showed small reflective particles at the corneal flap interface. The mean number of reflective particles was not statistically significantly different at 1 week (P= .078) and 1 month (P=. 28) using a femtosecond laser and a mechanical microkeratome.

CONCLUSIONS: Confocal microscopy findings at the corneal flap interface showed a similar number of particles using both systems. [J Refract Surg. 2007;23:305-307.]
A Cluster of Nocardia Keratitis After LASIK
Authors: Garg Prashant , Sharma Savitri , Vemuganti Geeta K , Ramamurthy Balasubramanya
Published: December 2018

ABSTRACT

PURPOSE: To report a cluster of Nocardia asteroides keratitis cases after LASIK.

METHODS: Retrospective review of the history and examination of three patients (four eyes) operated on the same day at a single center who developed postoperative keratitis. All patients underwent lifting of the superficial flap for microbiologic evaluation of the corneal scrapings. The operating surgeon was contacted to identify the possible source of contamination.

RESULTS: Two patients underwent simultaneous bilateral LASIK; however, only one developed postoperative keratitis in both eyes. One patient had unilateral surgery and developed keratitis in the operated eye. Microscopic examination of smears from all eyes revealed thin, branching, acid-fast, filamentous bacteria that were identified as Nocardia asteroides after culture. The infiltrates resolved with topical administration of amikacin sulphate (2.5%) and topical and oral trimethoprim-sulfamethoxazole. Final visual acuity ranged between 20/25 and 20/80. The operating surgeon had used the same blade and microkeratome in all patients.

CONCLUSIONS: Nocardia, a relatively unusual organism, can cause an epidemic of infection after LASIK. [J Refract Surg. 2007;23:309-312.]
Ultrasound Biomicroscopy for Determining Visian Implantable Contact Lens Length in Phakic IOL Implantation
Authors: Choi Ki Hwan , Chung Song Ee , Chung Tae Young , Chung Eui Sang
Published: December 2018

ABSTRACT

PURPOSE: To assess the efficacy of the ultrasound biomicroscopic (UBM) method in estimating the sulcus-to-sulcus horizontal diameter for Visian Implantable Contact Lens (ICL, model V4) length determination to obtain optimal ICL vault.

METHODS: The results of postoperative ICL vaults in 30 eyes of 18 patients were retrospectively analyzed. In 17 eyes, ICL length was determined using the conventional method, and in 13 eyes, ICL length was determined using the UBM method. The UBM method was carried out by measuring the sulcus to limbus distance on each side by 50 MHz UBM and adding the white-to-white diameter by caliper or Orbscan. The ICL vaults were measured using the UBM method at 1 and 6 months postoperatively and the results were compared between the two groups. Ideal ICL vault was defined as vault between 250 and 750 µm. The relation between the ICL vault, footplate location, and ICL power was also investigated.

RESULTS: In the UBM method group, ICL vault was within the ideal range in all 13 (100%) eyes at 1 and 6 months postoperatively, whereas in the conventional method group, 10 (58.8%) eyes showed ideal vault at 1 month postoperatively (P=.01) and 9 (52.9%) eyes showed ideal vault at 6 months postoperatively (P<.01). The ideal ICL footplate location was achieved in the ciliary sulcus in 11 (84.6%) eyes of the UBM method group and 10 (64.7%) eyes of the conventional method group. However, the differences between the two groups were not statistically significant. The ICL vault was not significantly affected by the ICL power.

CONCLUSIONS: Implantable Contact Lens length determined by the UBM method achieved significantly more ideal ICL vault than that of the conventional white-to-white method. The UBM method is superior to the conventional method in terms of predicting the sulcus-to-sulcus horizontal diameter for ICL length determination. [J Refract Surg. 2007;23:362-367.]
Calculating Intraocular Lens Geometry by Real Ray Tracing
Authors: Einighammer Jens , Oltrup Theo , Bende Thomas , Jean Benedikt
Published: December 2018

ABSTRACT

PURPOSE: An implementation of real ray tracing based on Snell's law is tested by predicting the refraction of pseudophakic eyes and calculating the geometry of intraocular lenses (IOLs).

METHODS: The refraction of 30 pseudophakic eyes was predicted with the measured corneal topography, axial length, and the known IOL geometry and compared to the manifest refraction. Intraocular lens calculation was performed for 30 normal eyes and 12 eyes that had previous refractive surgery for myopia correction and compared to state-of-the-art IOL calculation formulae.

RESULTS: Mean difference between predicted and manifest refraction for a 2.5-mm pupil were sphere 0.11±0.43 diopters (D), cylinder -0.18±0.52 D, and axis 5.13°±30.19°. Pearson's correlation coefficient was sphere r=0.92, P<.01; cylinder r=0.79, P<.01; and axis r=0.91, P<.01. Intraocular lens calculation for the normal group showed that the mean absolute error regarding refractive outcome is largest for SRK II (0.49 D); all other formulae including ray tracing result in similar values ranging from 0.36 to 0.40 D. Intraocular lens calculation for the refractive group showed that depending on pupil size (3.5 to 2.5 mm), ray tracing delivers values 0.95 to 1.90 D higher compared to the average of Holladay 1, SRK/T, Haigis, and Hoffer Q formulae.

CONCLUSIONS: It has been shown that ray tracing can compete with state-of-the-art IOL calculation formulae for normal eyes. For eyes with previous refractive surgery, IOL powers obtained by ray tracing are significantly higher than those from the other formulae. Thus, a hyperopic shift may be avoided using ray tracing even without clinical history. [J Refract Surg. 2007;23:393-404.]
Pressure Phosphene Tonometry Versus Goldmann Applanation Tonometry for Measuring Intraocular Pressure Before and After LASIK
Authors: Shemesh Gabi , Man Oran , Michaeli Adi , Varssano David , Lazar Moshe
Published: December 2018

ABSTRACT

PURPOSE: To compare pressure Phosphene tonometry with Goldmann applanation tonometry for measuring intraocular pressure (IOP) before and after LASIK.

METHODS: Forty-three (18 men and 25 women) consecutive healthy patients underwent complete pre- and postoperative LASIK ophthalmologic assessments including manifest and cycloplegic refraction, keratometry, and central corneal thickness. Three repetitive sets of pressure phosphene tonometry and Goldmann applanation tonometry measurements were performed the day before and 3 months following uneventful LASIK.

RESULTS: Mean preoperative spherical equivalent refraction was -4.70±2.50 diopters (D) (range: -1.50 to -12.90 D) and mean preoperative keratometry was 43.95±1.08 D. After LASIK, spherical equivalent refraction was +0.23±0.11 D and mean keratometry was 39.46±2.28 D. Preoperative pressure Phosphene tonometry (12.16±1.58 mmHg) and Goldmann applanation tonometry (12.01±1.55 mmHg) IOP measurements were similar. Postoperative IOP was 10.30±1.16 mmHg with Goldmann applanation tonometry and 12.20±1.62 mmHg with pressure phosphene tonometry. The postoperative IOP difference between Goldmann applanation tonometry and pressure phosphene tonometry was 0.15±1.12 mmHg (P=.41). The mean change in pachymetry after LASIK was 68.73±73 µm. The change in Goldmann applanation between preoperative and postoperative LASIK values was 1.71±1.43 mmHg (P<.0001), a change that was strongly correlated with changes in corneal thickness (R=0.75, P<.0001) and keratometry (R=0.72, P<.0001). No such correlations were found with pressure phosphene tonometry.

CONCLUSIONS: Goldmann applanation tonometrymeasured IOP decrease after LASIK is strongly correlated with a decrease in central corneal thickness and changes in keratometry, whereas pressure phosphene tonometry-measured IOP is independent of corneal thickness. Pressure phosphene tonometry appears to be a more reliable method for recording tonometry in these patients. [J Refract Surg. 2007;23:405-409.]
Technological Advances for Ocean Surface Measurements by the Consortium for Advanced Research on Transport of Hydrocarbons in the Environment (CARTHE)
Authors: Özgökmen Tamay M. , Boufadel Michel , Carlson Dan F. , Cousin Charles , Guigand Cedric , Haus Brian K. , Horstmann Jochen , Lund Bjoern , Molemaker Jeroen , Novelli Guillaume
Published: December 2018

AbstractFormed in the aftermath of the Deepwater Horizon event, the largest accidental marine oil spill, the Consortium for Advanced Research on Transport of Hydrocarbons in the Environment (CARTHE) focused on understanding the physical processes controlling the transport
of material from a deep blowout all the way to the coast. Even though CARTHE was initially a modeling-oriented team, it progressively became more focused on observations in order to collect the data needed for model evaluation. A number of new technological advances needed to be made to collect
the necessary data. This article reviews most of these, with special focus on surface sampling, where much of the oil is located during oil spills, as well as the measurement of near-field droplet size distribution.
HIV Interferes with the Dendritic Cell–T Cell Axis of Macrophage Activation by Shifting Mycobacterium tuberculosis–Specific CD4 T Cells into a Dysfunctional Phenotype
Authors: Singh Susmita K. , Larsson Marie , Schön Thomas , Stendahl Olle , Blomgran Robert
Published: December 2018

HIV coinfection is the greatest risk factor for transition of latent Mycobacterium tuberculosis infection into active tuberculosis (TB). Epidemiological data reveal both the reduction and the impairment of M. tuberculosis–specific CD4 T cells, although the cellular link and actual mechanisms resulting in immune impairment/suppression need further characterization. M. tuberculosis–specific CD4 T cells play a central role in development of protective immunity against TB, in which they participate in the activation of macrophages through the dendritic cell (DC)–T cell axis. Using an in vitro priming system for generating Ag-specific T cells, we explored if HIV–M. tuberculosis–infected (coinfected) human DCs can dysregulate the M. tuberculosis–specific CD4 T cell phenotype and functionality and subsequently mediate the failure to control M. tuberculosis infection in macrophages. After coculture with coinfected DCs, M. tuberculosis Ag-specific CD4 T cells lost their ability to enhance control of M. tuberculosis infection in infected macrophages. Coinfection of DCs reduced proliferation of M. tuberculosis Ag-specific CD4 T cells without affecting their viability, led to increased expression of coinhibitory factors CTLA-4, PD-1, and Blimp-1, and decreased expression of costimulatory molecules CD40L, CD28, and ICOS on the T cells. Expression of the regulatory T cell markers FOXP3 and CD25, together with the immunosuppressive cytokines TGF-β and IL-10, was also significantly increased by coinfection compared with M. tuberculosis single infection. Our data suggest a pattern in which HIV, through its effect on DCs, impairs the ability of M. tuberculosis-specific CD4 T cells to maintain a latent TB within human macrophages, which could play an early role in the subsequent development of TB.
Leishmania donovani Exploits Macrophage Heme Oxygenase-1 To Neutralize Oxidative Burst and TLR Signaling–Dependent Host Defense
Authors: Saha Shriya , Basu Moumita , Guin Subham , Gupta Purnima , Mitterstiller Anna-Maria , Weiss Guenter , Jana Kuladip , Ukil Anindita
Published: December 2018

Suppression of host oxidative burst is essential for survival of the intracellular parasite Leishmania donovani. Screening of macrophage antioxidant enzymes during infection revealed marked upregulation of the heme-degrading enzyme, heme oxygenase-1 (HO-1). Moreover, HO-1–silenced RAW macrophages depicted increased superoxide production and decreased parasite survival. HO-1 induction decreased cellular heme content, thereby inhibiting the heme-dependent maturation of gp91phox, a catalytic component of major reactive oxygen species–producing enzyme NAD(P)H oxidase. Decreased gp91phox expression resulted in reduced stability of p22phox, another component of the catalytic center of NAD(P)H oxidase. Replenishing infected cells with exogenous heme reversed these effects and restored NAD(P)H oxidase activity. Persistent HO-1 expression at late hour of infection prompted us to investigate its effect on other host defense parameters, and inhibition study revealed a reciprocal relationship of HO-1 with host proinflammatory responses. Among all the HO-1–mediated heme degradation products (CO, Fe, and biliverdin), only CO documented potent anti-inflammatory effects. Quenching of CO during infection increased the production of disease-resolving cytokines IL-12 and TNF-α. Coimmunoprecipitation experiments revealed that CO inhibited the interaction of TLR4 with MyD88 and TIR domain–containing adapter-inducing IFN-β, thereby dampening the activation of NF-κB and IFN regulatory factor 3–mediated production of proinflammatory cytokines. Administration of HO-1 inhibitor tin protoporphyrin IX dichloride in infected BALB/c mice led to a decrease in liver and spleen parasite burden along with increased production of IL-12 and TNF-α. These results suggest that HO-1 on one hand inhibits reactive oxygen species generation and on the other hand downregulates host favorable cytokine responses, thereby facilitating intramacrophage parasite survival.
Editorial
Authors: Tapia Ladino Marcela
Published: December 2018

Editorial
A Teaching Method Based on Virtual Worlds and Mastery Learning
Authors: Nunes Felipe Becker , Krassmann Aliane Loureiro , Tarouco Liane Margarida Rockenbach , De Lima José Valdeni
Published: December 2018

The evolution of virtual worlds in education has provided the creation of new pedagogical alternatives. In the present study, we explore this potential, integrating the Bloom’s Mastery Learning theory, designing a teaching method based on periodical assessments, and supplementary, support offered through the use of an OpenSim virtual world. An experiment was carried out during half of the school year of 2017, involving 74 sixth grade students in a Science class, divided in control and experimental groups. The results demonstrated better performance of the group using the virtual world in comparison to the group using the Moodle learning platform, in which, the post-test presented a slightly higher median for Group 2 (84.50) compared to Group 1 (83.00). As for the student’s impressions, it was in general of acceptance and positive impressions about the experience.
Marginalized Urban Indigenous Youth and the Virtual World of Second Life: Understanding the Past and Building a Hopeful Future
Authors: Cloutier Joe
Published: December 2018

A small independent high school in the Canadian West is using the affordances of the virtual world of Second Life to explore and reconstruct the colonial past of their students: marginalized urban Indigenous youth. The affordances of the virtual world make it possible to reconstruct the past, deconstruct the present and create a possible hope-filled future. This process is underpinned by pedagogies of engagement and emancipation on three virtual islands (sims) in the virtual world. The past was reconstructed and can be deconstructed on the Negan Tapeh sim. Negan Tapeh is a Cree phrase meaning “look to the future.” When the activities and quests associated with exploring and understanding the events of the past and their impact on the present are complete, participants are transported to the virtual present on the Boyle Street sim.Boyle Street is an inner-city area in Edmonton, Alberta, where most of the youth live or gravitate to. In Canada and the United States, inner city areas have historically been synonymous with depressed and run-down parts of the city where petty crime, violence and substance abuse are woven into the fabric of daily life. On Boyle Street, the youth are tasked with completing assignments (quests or hunts) distributed by teachers (scripted agents) in the sim’s Boyle Street High School. When the three quests are completed, participants receive their key to the future. The future unfolds on the third sim Urban Hope.This paper underlines the importance of the virtual world in educational projects with marginalized youth.
The Game of Inventing: Ludic Heuristics, Ontological Play, and Pleasurable Research
Authors: Euteneuer Jacob Steven
Published: December 2018

Everyone plays games, but very few of us have experience in creating games. Children are taught simple folk-games like Tag and The Floor is Lava but rarely graduate on into creating their own unique experiences through invented games. This proposal positions games as a culturally relevant medium that often suffers from players inability to understand the motivations and purpose behind a game’s creation. Drawing on examples from diverse fields such as visual design, leisure studies, human-computer interaction, and multimodal composition, this chapter examines the potential for the development of “ludic heuristics” which allow composers and rhetors to both create and analyze games and play through the process of inventing their own games. This heuristic breaks down games into three components: their materials, limits, and goals. An ontological understanding of the objects, affordances, and motivations for playing a game can then be used to analyze existing games with the ultimate goal of having students create their own serious or persuasive games. As scholars such as Rebekah Schultz Colby (2017) have noted, there is a push to use digital and board games in the classroom, though there is very little established in terms of actual implementation, best practice, and pedagogical foundation for the inclusion of games. This chapter analyzes the possibilities for developing new invention practices for creating games that go beyond cloning and imitation. While the field of rhetoric has a long history of using innovative methods applied to grammar (Christensen, 1963), reappropriation and remix (Palmeri, 2012), and style (Lanham, 2006), there is little research on the application of heuristics to develop play both as an end and as a means in composing multimodal texts. This chapter argues that a framework of materials, limits, and goals lead to the development of a ludic heuristic which can then be used to produce games which model systems, produce arguments, and express beliefs.
Biological image analysis using deep learning-based methods: Literature review
Authors: Wang Hongkai , Shang Shang , Long Ling , Hu Ruxue , Wu Yi , Chen Na , Zhang Shaoxiang , Cong Fengyu , Lin Sijie
Published: December 2018

Automatic processing large amount of microscopic images is important for medical and biological studies. Deep learning has demonstrated better performance than traditional machine learning methods for processing massive quantities of images; therefore, it has attracted increasing attention from the research and industry fields. This paper summarizes the latest progress of deep learning methods in biological microscopic image processing, including image classification, object detection, and image segmentation. Compared to the traditional machine learning methods, deep neural networks achieved better accuracy without tedious feature selection procedure. Obstacles of the biological image analysis with deep learning methods include limited training set and imperfect image quality. Viable solutions to these obstacles are discussed at the end of the paper. With this survey, we hope to provide a reference for the researchers conducting biological microscopic image processing.
Investigation on the status of radiation therapy for nasopharyngeal cancer in Chongqing city
Authors: Zhu Ying , Wang Ge , Li Guanghui , Li Jianjun , Jin Fu , Zhang Tao , Liu Xuefen , Sun Jianguo
Published: December 2018

Objective:

The objective of the study is to investigate the regional capacity and implementation of radiotherapy for nasopharyngeal carcinoma (NPC) in Chongqing city.

Materials and Methods:

The questionnaires, self-designed electronic forms in a uniform format, were distributed to 37 radiotherapy institutions, which covered all the medical units equipped with radiotherapy equipment in this city.

Results:

Of the 37 radiotherapy units in Chongqing, 27 could deliver radiotherapy for NPC, but the remaining 10 institutions could not due to equipment limitations. From January to December 2017, a total of 2904 patients with NPC were treated with radiotherapy. Patients from the five teaching hospitals in the main districts of the city accounted for 86% of the participants. There were four representative types of radiotherapy plan based on radiation technology among these units. Of the 37 units, 18 used intensity-modulated radiotherapy, 6 adopted three-dimensional conformal radiotherapy, 2 chose volumetric modulated arc therapy, and 1 delivered two-dimensional traditional radiotherapy; only 10 units applied magnetic resonance imaging (MRI)-computed tomography registration and fusion for gross tumor volume delineation in NPC treatment, and only 3 units routinely acquired nasopharyngeal and neck MRI scans to evaluate tumor shrinkage during treatment.

Conclusion:

Obvious distinctions exist between various units in Chongqing city in radiotherapeutic strategy, radiotherapy plan, frequency of image-guided radiation therapy, and mid-treatment evaluation for NPC radiotherapy. We need to learn and apply NPC guideline and consensus to improve NPC radiotherapy in Chongqing and to construct a rule with regional characteristics.
A new approach to decay estimates – Application to a nonlinear and degenerate parabolic PDE
Authors: Porzio Maria Michaela
Published: December 2018

In this paper we describe a new method to derive different type of decay estimates for solutions of evolution equations which allow to describe the asymptotic behavior of the solutions both in presence or absence of „immediate" regularizing properties. Moreover, we give various examples of applications some of which new and dealing with a class of nonlinear problems with degenerate coercivity.
On mutually permutable products of finite groups
Authors: Ballester-Bolinches Adolfo , Li Yangming , Pedraza-Aguilera Mari Carmen , Su Ning
Published: December 2018

The main purpose of this paper is to study mutually permutable products

G = AB

in which the subgroups of prime order

p

and cyclic of order

4

(if

p = 2

) of the largest normal subgroup of

G

contained in

A\cap B

are well situated in

G

. Our results confirm once again the important role of the intersection of the factors in the structural study of mutually permutable products.
Nodal solutions for nonlinear nonhomogeneous Robin problems
Authors: Papageorgiou Nikolaos S. , Rădulescu Vicenţiu D. , Repovš Dušan D.
Published: December 2018

We consider a nonlinear Robin problem driven by a nonhomogeneous differential operator plus an indefinite potential. The reaction term is a Carathéodory function satisfying certain conditions only near zero. Using suitable truncation, comparison and cut-off techniques, we show that the problem has a sequence of nodal solutions converging to zero in the

C^1(\overline{\Omega})

-norm.
El informe de sostenibilidad del Trabajo de Fin de Grado del área de las ingenierías
Authors: Climent J. , Cabré J. , Sánchez F. , Martín C. , Vidal E. , López D.
Published: December 2018

La elaboración del informe de sostenibilidad de un proyecto de ingeniería es ya una práctica habitual en todas las empresas importantes del sector TIC. Los ingenieros que formamos ahora en las universidades deberán, sin duda, incluir informes de sostenibilidad en sus proyectos cuando ejerzan profesionalmente. La enseñanza necesaria para elaborar un buen informe de sostenibilidad de un Trabajo de Fin de Grado ya no es una opción, es una necesidad si queremos formar ingenieros de calidad. Desgraciadamente, no todos los profesores han tenido la experiencia necesaria para poder orientar a los estudiantes en la elaboración de un informe de sostenibilidad de un proyecto. Esto provoca que, a menudo, los estudiantes se encuentren perdidos al elaborar dicho informe, y acaben realizándolo sin hacer ninguna reflexión profunda sobre la sostenibilidad de su proyecto. Con el fin de orientar al estudiante en la valoración de la sostenibilidad de su Trabajo de Fin de Grado, en la Facultat de Informática de Barcelona, se ha diseñado una guía para la elaboración del informe de sostenibilidad de un Trabajo de Fin de Grado. En este artículo se presenta con detalle esta herramienta. La guía para elaborar el informe de sostenibilidad no sólo es de utilidad para los estudiantes, sino que también es una referencia para los directores y miembros de tribunal de los Trabajos de Fin de Grado.