bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Discreteness-driven Relaxation of Collisionless Gravitating Systems: Entropy Evolution in External Potentials, N-dependence, and the Role of Chaos
Authors: Silva Leandro Beraldo e , de Siqueira Pedra Walter , Valluri Monica , Sodré Laerte , Bru Jean-Bernard 
Published: January 2019

Abstract
We investigate the old problem of the fast relaxation of collisionless N-body systems that are collapsing or perturbed, emphasizing the importance of (noncollisional) discreteness effects. We integrate orbit ensembles in fixed potentials, estimating the entropy to analyze the time evolution of the distribution function. These estimates capture the correct physical behavior expected from the second law of thermodynamics, without any spurious entropy production. For self-consistent (i.e., stationary) samples, the entropy is conserved, while for non-self-consistent samples, it increases within a few dynamical times, stabilizing at a maximum (even in integrable potentials). Our results make transparent that the main ingredient for this fast collisionless relaxation is the discreteness (finite N) of gravitational systems in any potential. Additionally, in nonintegrable potentials, the presence of chaotic orbits accelerates the entropy production. Contrary to the traditional violent relaxation scenario, our results indicate that a time-dependent potential is not necessary for this relaxation. For the first time, in connection with the Nyquist–Shannon theorem, we derive the typical timescale

for this discreteness-driven relaxation, with slightly weaker N-dependencies for nonintegrable potentials with substantial fractions of chaotic orbits. This timescale is much smaller than the collisional relaxation time even for small-N systems such as open clusters and represents an upper limit for the relaxation time of real N-body collisionless systems. Additionally, our results reinforce the conclusion of Beraldo e Silva et al. that the Vlasov equation does not provide an adequate kinetic description of the fast relaxation of collapsing collisionless N-body systems.
The R-Process Alliance: Spectroscopic Follow-up of Low-metallicity Star Candidates from the Best & Brightest Survey
Authors: Placco Vinicius M. , Santucci Rafael M. , Beers Timothy C. , Chanamé Julio , Sepúlveda María Paz , Coronado Johanna , Rossi Silvia , Lee Young Sun , Starkenburg Else , Youakim Kris , Barrientos Manuel , Ezzeddine Rana , Frebel Anna , Hansen Terese T. , Holmbeck Erika M. , Ji Alexander P. , Rasmussen Kaitlin C. , Roederer Ian U. , Sakari Charli M. , Whitten Devin D. 
Published: January 2019

Abstract
We present results from an observing campaign to identify low-metallicity stars in the Best & Brightest Survey. From medium-resolution (R ∼ 1200–2000) spectroscopy of 857 candidates, we estimate the stellar atmospheric parameters (

,

, and

), as well as carbon and α-element abundances. We find that 69% of the observed stars have

≤ −1.0, 39% have

≤ −2.0, and 2% have

≤ −3.0. There are also 133 carbon-enhanced metal-poor (CEMP) stars in this sample, with 97 CEMP Group I and 36 CEMP Group II stars identified in the A(C) versus [Fe/H] diagram. A subset of the confirmed low-metallicity stars were followed-up with high-resolution spectroscopy, as part of the R-process Alliance, with the goal of identifying new highly and moderately r-process-enhanced stars. Comparison between the stellar atmospheric parameters estimated in this work and from high-resolution spectroscopy exhibit good agreement, confirming our expectation that medium-resolution observing campaigns are an effective way of selecting interesting stars for further, more targeted, efforts.
Extragalactic Imprints in Galactic Dust Maps
Authors: Chiang Yi-Kuan , Ménard Brice 
Published: January 2019

Abstract
Extragalactic astronomy relies on the accurate estimation of source photometry corrected for Milky Way dust extinction. This has motivated the creation of a number of “Galactic” dust maps. We investigate whether these maps are contaminated by extragalactic signals using the clustering-redshift technique, i.e., by measuring a set of angular cross-correlations with spectroscopic objects as a function of redshift. Our tomographic analysis reveals imprints of extragalactic large-scale structure patterns in nine out of 10 Galactic dust maps, including all infrared-based maps as well as “stellar” reddening maps. When such maps are used for extinction corrections, this extragalactic contamination introduces redshift- and scale-dependent biases in photometric estimates at the millimagnitude level. It can affect both object-based analyses, such as the estimation of the Hubble diagram with supernovae, as well as spatial statistics. The bias can be appreciable when measuring angular correlation functions with low amplitudes, such as lensing-induced correlations or angular correlations for sources distributed over a broad redshift range. As expected, we do not detect any extragalactic contamination for the dust map inferred from 21 cm H i observations. Such a map provides an alternative to widely used infrared-based maps but relies on the assumption of a constant dust-to-gas ratio. We note that, using the Wide-field Infrared Survey Explorer 12 μm map sensitive to polycyclic aromatic hydrocarbons (PAHs), an indirect dust tracer, we detect the diffuse extragalactic PAH background up to z ∼ 2. Finally, we provide a procedure to minimize the level of biased magnitude corrections in maps with extragalactic imprints.
Investigation of the basic Haar wavelet-transformations in the problem of decryption of space images on detection of waste disposal fields
Authors: Kazaryan Maretta , Shahramanian Mikhail , Zabunov Svetoslav 
Published: January 2019

In this paper, we study the use of orthogonal transformations, namely, the basic Haar wavelet transforms, for data processing of the Earth remote sensing.
The internal structure of orthogonal Haar transforms is considered. The Haar matrix is divided into blocks of the same type, so that parallelization of the computations is possible. The expediency of replacing the spectral components corresponding to the whole block (or several blocks) of the original matrix with zeros is asserted. Theoretical and experimental studies are carried out to improve the results of image classification (on the example of cluster analysis). The Haar wavelet expansion coefficients are used as indicators when decoding space images for the presence of waste disposal sites.
The aim of this paper is to describe the approach, on the basis of which an optimal method is established on a class of vectors with real components, application of two-dimensional discrete Haar wavelet transformations in the problem of recognition of space images for the presence of waste disposal sites. General methodology of research. The paper uses elements of mathematical analysis, wavelet analysis, the theory of discrete orthogonal transformations, and methods for decoding cosmic images. Scientific novelty. Encoding by means of conversion is an indirect method, especially effective in processing of two-dimensional signals, in particular, space images used for remote sensing of the Earth. We propose the approach that takes into account the structure of the wavelet-Haar matrix, while recognizing waste disposal fields by means of space images. The article comprises the result of the experimental application of wavelet-Haar transformations for decoding of space images. We consider this case, both with and without the technique of taking into account the structure of the wavelet-Haar matrices.
Enhanced Visualization of Capsulorhexis With Indocyanine Green Staining in Pediatric White Cataracts
Authors: Guo Suqin , Caputo Anthony , Wagner Rudolph , DeRespinis Patrick 
Published: January 2019

ABSTRACT
Purpose: To evaluate the enhancement of the visualization of the anterior lens capsule with indocyanine green (ICG) in pediatric dense, mature cataracts.
Patients and Methods: Six children (10 eyes) 4 to 9 years old with complete, white cataracts underwent ICG-enhanced cataract surgery.
Results: All of the eyes showed a complete con tinuous curvilinear capsulorhexis and a well-centered intracapsular implant. No surgical or postoperative complications were encountered.
Conclusion: Staining the anterior capsule with ICG is an excellent way to facilitate performance of an anterior capsulorhexis in pediatric white cataracts.
J Pediatr Ophthalmol Strabismus 2003;40:268-271.
Ocular and Systemic Findings Associated With Optic Disc Colobomas
Authors: Berk A Tülin , Yaman Aylin , Saatçi A Osman 
Published: January 2019

ABSTRACT
Purpose: To determine the ocular and systemic anomalies associated with optic disc colobomas.
Patients and Methods: The records of patients with a diagnosis of isolated optic disc coloboma and chorioretinal coloboma with optic disc involvement were retrospectively reviewed.
Results: Fifteen patients were included in the study. Of the 30 eyes, the optic disc and choroid were involved in 18, an isolated disc coloboma was present in 5, a normal optic disc was present in 4, and the optic disc could not be identified because of extreme microphthalmia in 1. Of the optic discs outside the fundus colobomas, 1 had an abnormal shape and 1 had optic atrophy and hypoplasia. Eight patients had bilateral but asymmetric involvement of the optic nerve with the coloboma. Fourteen eyes of 9 patients were microphthalmia Nine eyes of 6 patients had microcornea. One patient had a nonrhegmatogenous retinal detachment at the time of diagnosis. One eye had a retrobulbar cyst with microphthalmia. Eight (53%) of the patients had sensory strabismus. Two patients had unilateral cortical lens opacities. Associated systemic findings were present in 6 (40%) of the 1 5 patients.
Conclusions: Optic disc colobomas have a wide variety of presentations. Poor visual acuity was observed mostly in eyes with macular involvement and microphthalmia.
J Pediatr Ophthalmol Strabismus 2003;40:272-278.
Nonpenetrating Deep Sclerectomy With the Use of Adjunctive Mitomycin C
Authors: Neudorfer Meira , Sadetzki Siegal , Anisimova Svetlana , Geyer Orna 
Published: January 2019

* BACKGROUND AND OBJECTIVE: To determine whether adjunctive use of mitomycin C (MMC) would increase the success rate of primary nonpenetrating deep sclerectomy with collagen implant.
* PATIENTS AND METHODS: Twenty-six patients (26 eyes) with primary open-angle glaucoma uncontrolled with maximally tolerated medical therapy were randomly assigned to undergo nonpenetrating deep sclerectomy and collagen implant, either with (13 eyes) or without (13 eyes) 0.3 mg/mL of adjunctive MMC for 3 minutes. Intraocular pressure (IOP), number of glaucoma medications, and visual acuity were assessed before and 12 and 24 months after surgery.
* RESULTS: The mean age of the study patients was similar in both groups (MMC = 68.1 ± 8 years, control = 65.8 ± 6.8 years). At the 12- and 24-month follow-up visits, the mean IOP with or without medications was lower in the MMC group than in the control group (15.6 ± 3.5 vs 17.2 ± 3.9 mm Hg at 12 months and 15.8 ± 5.6 vs 17.8 ± 2.8 mm Hg at 24 months, respectively). The IOP with or without medications significandy decreased after surgery in both groups (P < .05). Twelve months after surgery, the IOP decreased by 48% in the MMC group and by 35% in the control group. At the end of follow-up (24 months), the IOP decreased by 48% in the MMC group and by 32% in the control group (P= .01). The mean number of glaucoma medications decreased after surgery, there was no significant difference in complications (hyphema and suprachoroidal hemorrhage), and visual acuity was unchanged throughout the study in both groups.
* CONCLUSION: The use of MMC in nonpenetrating deep sclerectomy with collagen implant is safe and improves surgical results.
[Ophthalmic Surg Lasers Imaging 2004;35:6-12.]
Quantitative Lacrimal Scintigraphy After Dacryocystorhinostomy
Authors: Zilelioglu Güler , Küçük Özlem , Tekeli Oya , Günan Fatih , Aras Gülseren 
Published: January 2019

* BACKGROUND AND OBJECTIVE: To evaluate lacrimal drainage in patients who have undergone successful dacryocystorhinostomy using quantitative dacryoscintigraphy.
* PATIENTS AND METHODS: This study included 72 eyes of 72 patients. There were 26 males and 46 females, with a mean age of 39.6 years (range, 8 to 67 years). The patients were subdivided into three groups. Group 1 consisted of 35 eyes with external dacryocystorhinostomy, group 2 consisted of 1 5 eyes with endoscopic dacryocystorhinostomy, and group 3 consisted of 22 eyes with conjunctival dacryocystorhinostomy with a Jones tube. There was no epiphora in patients and the lacrimal drainage systems were patent by irrigation. The other normal eyes of the patients were evaluated as controls.
* RESULTS: In groups 1 and 2, the mean T,/2 values for the palpebral aperture were lower than those for normal eyes, and this difference was statistically significant (P < .01). In group 3, no significant difference was detected in the mean T17, values for the palpebral aperture.
* CONCLUSIONS: Tear flow was slower in patients who had had external and endoscopic dacryocystorhinostomy, but conjunctival dacryocystorhinostomy did not affect T1/2 values for the palpebral aperture.
[Ophthalmic Surg Lasers Imaging 2004;35:3740.]
Diode Laser Contact Transscleral Cyclophotocoagulation: Getting the Most From the G-Probe
Authors: Noecker Robert J , Kelly Thomas , Patterson Emily , Herrygers Lisa A 
Published: January 2019

* BACKGROUND AND OBJECTIVE: To deter mine the multi-use behavior of the G-probe that is traditionally marketed as a single-use cyclophotocoagulation instrument.
* MATERIALS AND METHODS: A diode laser equipped with a G-probe was used to perform cyclophotocoagulation of the ciliary body in 4 human cadaver eyes and 15 porcine eyes (1,750 mW X 2 seconds). A determination of G-probe effectiveness was made following measurements of G-probe energy output, scanning electron microscopy examination of probe tips, and histologic examination of treated tissue.
* RESULTS: The mean energy output of 12 of the 15 G-probes remained constant at 3.10 J (range, 3.04 to 3.14 J) for 20 treatment cycles of 20 applications each. Scanning electron microscopy demonstrated minimal surface change. Three G-probes suffered a significant drop-off in energy output during the experiment, and scanning electron microscopy showed significant surface change. Histologic examination of human eyes treated with laser revealed disruption of the ciliary body stroma and separation of pigmented and nonpigmented layers of the ciliary epithelium. More pronounced tissue necrosis and disruption was observed in eyes treated with newer G-probes. Milder coagulative damage with cellular vacuolization was observed in G-probes used for higher numbers of treatment cycles.
* CONCLUSION: Every G-probe tested delivered more than 100 consecutive applications of laser energy before any loss of efficiency was noted. This suggests that in the absence of obvious structural damage, a G-probe may be safely used for treatment of at least 5 eyes.
[Ophthalmic Surg Lasers Imaging 2004;35:124-130.]
Outcome of Therapeutic Penetrating Keratoplasty in Infectious Keratitis
Authors: Sukhija Jaspreet , Jain Arun K 
Published: January 2019

* BACKGROUND AND OBJECTIVE: To study the outcome of therapeutic penetrating keratoplasty in eyes with microbial keratitis.
* PATIENTS AND METHODS: A prospective database on 134 therapeutic cornea transplants in 134 patients recorded demographic details on age and gender of the patient, indication for surgery, size of the donor and recipient bed, graft clarity, complications, and residual morbidity. Patients included in this analysis had a minimum follow-up of 1 year. All patients underwent therapeutic penetrating keratoplasty by a similar method that involved a donor button that was oversized by 0.5 mm and 16 bites of interrupted sutures.
* RESULTS: Most of the 134 ulcers needing therapeutic grafts were bacterial (n = 54) or fungal (n = 54). One hundred eighteen eyes had perforation at presentation. One hundred six (90%) of the therapeutic grafts achieved anatomical success. The most common complication of glaucoma occurred in 22% of eyes with presurgical perforated ulcers and 1% of nonperforated ulcers. Persistent epithelial defects were significandy more frequent in grafts of 9 mm or more (P= .05).
* CONCLUSIONS: Our results confirm that therapeutic penetrating keratoplasty for infections is successful in restoring anatomic integrity in most eyes.
[Ophthalmic Surg Lasers Imaging 2005;36:303-309.]
Assessment of the Effects of Morphological Changes Related to Age-Related Macular Degeneration on Optical Coherence Tomography Retinal Thickness Measurements
Authors: Menke Marcel N , Feke Gilbert T 
Published: January 2019

* BACKGROUND AND OBJECTIVE: Age-related macular degeneration (AMD) leads to morphological changes that can interfere with optical coherence tomography retinal thickness measurements. The effects of AMD on two available retinal thickness scan modes were tested.
* PATIENTS AND METHODS: Ninety-four scans, equally divided into Radial Line Scans (RLS) and Fast Macula Scans (FMS), of 42 patients with AMD were reviewed. Patients were graded into 4 categories regarding AMD severity. Each scan mode was evaluated for each AMD category.
* RESULTS: In dry moderate AMD, 2% of the RLS and 5% of the FMS thickness measurements failed. In dry progressed AMD, the RLS mode performed better (26% failure rate) than the FMS mode (42% failure rate). However, in exudative AMD the FMS mode performed better (6% failure rate) than the RLS mode (28% failure rate). The difference between the RLS and FMS performance in dry progressed AMD compared with exudative AMD was significant (P < .0001).
* CONCLUSION: The optical coherence tomography retinal thickness scan modes perform differently, depending on AMD severity. Retinal thickness algorithms with better performance are needed to facilitate measurements in patients with AMD.
[Ophthalmic Surg Lasers Imaging 2005;36:310314.1
Potential Applications of Optical Coherence Tomography in Posterior Segment Trauma
Authors: Rumelt Shimon , Karatas Muge , Ophir Avinoam 
Published: January 2019

* BACKGROUND AND OBJECTIVE: To describe potential clinical applications of optical coherence tomography (OCT) in diagnosis and surgical timing in eyes with posterior segment trauma.* PATIENTS AND METHODS: In a noncomparative study, 7 consecutive patients who had open-globe or closed-globe injury and were found to have posterior abnormality that could also be detected by OCT are described.* RESULTS: All patients had documented OCT abnormalities in the posterior segment. In one patient with a penetrating injury, two metal foreign bodies were located in the posterior segment, one in the vitreous compartment coupled with inflammatory reaction and localized posterior vitreous detachment and the other embedded in the retina. In a second patient with a penetrating injury, OCT revealed the appearance of posterior vitreous detachment 5 days after injury. A closed-globe injury in one patient resulted in anterior optic neuropathy, manifested as disc edema and thickening of the circumpapillary retinal nerve fiber layer. The other patients had received blunt trauma and were found to have either full-thickness macular holes (2 patients), retinal pigment epithelium detachment at the papillomacular bundle site (1 patient), or macular edema (1 patient).* CONCLUSIONS: OCT may serve as an important adjunct imaging device in evaluation of injuries to the posterior segment, qualitatively and quantitatively. It has potential in diagnosing subtle key abnormalities and in follow-up of these injuries.[Ophthalmic Surg Lasers Imaging 2005;36:315-322.]
Bilateral Optic Disc Edema in Patients With Severe Systemic Arterial Hypertension: Clinical Features and Visual Acuity Outcomes
Authors: Scott Ingrid U , Flynn Harry W , Al-Attar Luma , Ganser Gail L , Aragon Antonio V , Lam Byron L 
Published: January 2019

* BACKGROUND AND OBJECTIVE: To report clinical features and visual outcomes in patients with bilateral optic disc edema and severe systemic arterial hypertension.
* PATIENTS AND METHODS: Records were reviewed of patients with bilateral optic disc edema, severe arterial hypertension, and 3 or more months of follow-up evaluated at Bascom Palmer Eye Institute between 1982 and 2003.
* RESULTS: Sixteen patients (median age = 41 years; median follow-up = 31 months) were identified. Median blood pressure on initial eye examination was 220 mm Hg systolic and 126 mm Hg diastolic. Among all study eyes, median visual acuity was 20/55 on presentation. At the last follow-up examination, an acuity of 20/50 or better was achieved in 20 (63%) eyes; 12 (75%) patients achieved a final acuity of 20/50 or better in at least one eye. Posterior segment abnormalities at last follow-up included disc pallor (n = 16), macular star (n = 7), retinal pigment epithelial atrophy (n = 7), epiretinal membrane (n = 5), branch retinal vein occlusion (n = 4), and persistent disc edema (n = 2). Causes of final acuity of less than 20/50 included optic atrophy, epiretinal membrane, serous retinal detachment, macular hole, and branch retinal vein occlusion.
* CONCLUSION: Most patients with bilateral optic disc edema and severe arterial hypertension maintained visual acuity of 20/50 or better in at least one eye.
[Ophthalmic Surg Lasers Imaging 2005,36:374-380.]
Long-Term Results of External Dacryocystorhinostomy
Authors: Warren John F , Seiff Stuart R , Kavanagh Marsha C 
Published: January 2019

* BACKGROUND AND OBJECTIVE: To evaluate the long-term success following external dacryocystorhinostomy, which is used as a standard in comparing endoscopic or laser techniques.
* PATIENTS AND METHODS: A chart review of 128 patients (150 procedures) undergoing external dacryocystorhinostomy within a 14-year period was undertaken. Patient demographics, symptoms, examination findings, surgical and anesthesia information, postoperative course, and complications were recorded. Lack of tearing or evidence of dacryocystitis at the final postoperative visit was considered a successful result.
* RESULTS: External dacryocystorhinostomy was found to be highly successful, with an overall 93% success rate at an average follow-up of 2.7 years. Kaplan-Meier analysis of the data, applied for the first time in this study, predicts a success rate of 90% beyond 4 years. Most important, this demonstrated that most surgical failures were identified in the first 2 years. Postoperative complications were rare and the surgical scar was not a source of patient concern in most cases.
* CONCLUSIONS: This study confirms that external dacryocystorhinostomy is a highly successful longterm solution to nasolacrimal duct obstruction with low morbidity.
[Ophthalmic Surg Lasers Imaging 2005;36:446450.]