bluuebunny/crossref_metadata_2025 huggingface dataset:
Errors in Diagnosis and Margin Determination of Soft-Tissue Sarcomas Initially Treated at Non-Tertiary Centers
Authors: Randall R L , Bruckner J D , Papenhausen M D , Thurman T , Conrad E U
Published: December 2019

Abstract

One hundred four patients with soft-tissue sarcoma referred to our institution who were initially managed at an outside medical center were retrospectively reviewed. The accuracy of histologic diagnosis and adequacy of tumor resection performed at these centers was evaluated. Review of the original pathologic specimens was performed. Thirty-seven percent of the histologic diagnoses were changed, and 82% of cases with excisional or wide resections had positive margins. The Incidence of errors in diagnosis and inadequate tumor resection suggest that biopsy and histologic analysis of sarcomas should be performed by physicians experienced in their management.
Corneal Keratocyte Apoptosis Following Topical Intraoperative Mitomycin C in Rabbits
Authors: Chang Shu-Wen
Published: December 2019

ABSTRACT

PURPOSE: To determine the soaking duration and concentration effect of mitomycin C (MMC) on the corneal keratocyte following single intraoperative application.

METHODS: Two hundred ten pigmented rabbit eyes underwent mechanical epithelium debridement of the central 10-mm cornea followed by soaking of six different solutions: MMClA: 0.01% MMC x 1 minute; MMClB: 0.01% MMC X 2 minutes; MMC2A: 0.02% MMC x 1 minute; MMC2B: 0.02% MMC X 2 minutes; BSSl: balanced salt solution (BSS) x 1 minute; and BSS2: BSS x 2 minutes. Thirty-five eyes were allocated into each group. Changes of the central corneal thickness, corneal clarity score, and keratocyte apoptosis were examined on days 0, 1, 2, 3, 5, 7, and 14.

RESULTS: A significant increase of central corneal thickness and corneal clarity score was noted in all MMC treated groups. The central corneal thickness recovered to its baseline level whereas the corneal clarity score remained increased at 2 weeks. The changes were more significant in MMC2 than in MMCl corneas. However, changes of central corneal thickness and corneal clarity score were more significant in MMClB than in MMClA, whereas no difference was noted between MMC2A and MMC2B. Significantly higher stromal keratocyte loss and keratocyte apoptosis, from superficial to deep corneal stroma, was noted in MMCl and MMC2 groups up to 14 days postoperatively, in a soaking duration and dose-dependent manner.

CONCLUSIONS: Single application of MMC on the corneal surface caused soaking concentration and duration dependent corneal edema and keratocyte apoptosis in this rabbit model. [J Refract Surg. 2005;21:446-453].
Two Cases of Pneumococcal Keratitis Following Myopic LASIK
Authors: Lifshitz Tova , Levy Jaime , Raiskup Frederik , Klemperer Itamar , Frucht-Pery Joseph
Published: December 2019

ABSTRACT

PURPOSE: To report two cases of pneumococcal keratitis after LASIK.

METHODS: Retrospective interventional small case series of two patients who underwent bilateral LASIK for myopia and developed pneumococcal keratitis after surgery. This complication was encountered 2 days after surgery in one eye in both cases. The corneal flap was lifted, and irrigation and cultures from the stromal bed performed. Topical and subconjunctival antibiotics were started.

RESULTS: Culture revealed Streptococcus pneumoniae in both cases. The infiltrates responded well to treatment. One year after the procedure, uncorrected visual acuity is > 20/40 in both cases.

CONCLUSIONS: Pneumococcal keratitis can complicate LASIK. Patients should be informed of this potential complication, as prompt treatment is crucial. [J Refract Surg. 2005;21:498-501.]
Zonal Matrix Iterative Method for Wavefront Reconstruction From Gradient Measurements
Authors: Panagopoulou Sophia I , Neal Daniel P
Published: December 2019

ABSTRACT

PURPOSE: To present an alternate method to Zernike decomposition (modal) of wavefront reconstruction using iterative implicit solution to the finite difference equations (zonal).

METHODS: Different reconstruction methods, modal and zonal, were compared and the advantages of each method were analyzed.

RESULTS: Although the modal or Zernike method allows for quantitative interpretation of some of the aberrations, it is cumbersome for use with fine details and may lead to errors for eyes with keratoconus or other rapidly varying aberration. The zonal method produces a very high-resolution map that can be used for identifying irregular structures.

CONCLUSIONS: The distinction between the two methods is useful to maintain, and the solution methods are generally different. In practice, both methods are useful and, with modern computers, both zonal and lowerorder modal may be calculated rapidly. The difference between the wavefronts derived from the two methods may provide useful insight or interpretation of the information. [J Refract Surg. 2005;21:S563-S569.]
Adaptive Optics Ophthalmoscopy: Results and Applications
Authors: Pallikaris A
Published: December 2019

ABSTRACT

PURPOSE: The living human eye's optical aberrations set a limit to retinal imaging in the clinical setting. Progress in the field of adaptive optics has offered unique solutions to this problem. The purpose of this review is to summarize the most recent advances in adaptive optics ophthalmoscopy.

METHODS: Adaptive optics technology has been combined with flood illumination imaging, confocal scanning laser ophthalmoscopy, and optical coherence tomography for the high resolution imaging of the retina.

RESULTS: The advent of adaptive optics technology has provided the technical platform for the compensation of the eye's aberration and made possible the observation of single cones, small capillaries, nerve fibers, and leukocyte dynamics as well as the ultrastructure of the optic nerve head lamina cribrosa in vivo.

CONCLUSIONS: Detailed imaging of retinal infrastructure provides valuable information for the study of retinal physiology and pathology. [J Refract Surg. 2005;21: S570-S574.]
Optimized Prolate Corneal Ablation: Case Report of the First Treated Eye
Authors: El-Danasoury Alaa , Bains Harkaran S
Published: December 2019

ABSTRACT

PURPOSE: To present the first patient treated with an optimized prolate ablation algorithm (OPA) with the NIDEK Advanced Vision Excimer laser platform (NAVEX; NIDEK, Gamagori, Japan).

METHODS: A patient with moderate myopia and large scotopic pupils received contralateral LASIK treatment, treating one eye with OPA and the other with conventional treatment.

RESULTS: At 3 months postoperatively, corneal topography and wavefront analysis show a prolate result with the OPA treatment and an oblate result with the conventional treatment.

CONCLUSIONS: The creation of prolate cornea over the entire scotopic pupil, the reduction of spherical aberrations, and an ablation architecture that compensate for age-related changes was achieved immediately after LASIK. The OPA treatment may result in better visual quality over the long-term compared to conventional LASIK. [J Refract Surg. 2005;21(Suppl):S598-S602.]
Efficacy and Safety of LASIK in 10,052 Eyes of 5081 Myopic Chinese Patients
Authors: Sun Lanping , Liu Guifen , Ren Yanjun , Li Ji , Hao Junhua , Liu Xia , Zhang Yajuan
Published: December 2019

ABSTRACT

PURPOSE: To analyze the outcomes and incidence of postoperative complications in a large series of patients undergoing LASIK for myopia.

METHODS: All 5081 patients (10,052 eyes) diagnosed with myopia at The Third Hospital of Handan, China, from September 2003 through March 2005 were studied. All study eyes underwent LASIK with 1-month follow-up. Spherical equivalent refraction, best spectacle-corrected visual acuity (BSCVA), and uncorrected visual acuity (UCVA) were measured before and after surgery and intra- and postoperative complications were recorded.

RESULTS: Uncorrected visual acuity at 1-month follow-up of 9555 (95.1%) eyes reached or exceeded the preoperative BSCVA. Hemorrhage of corneal limbus during surgery occurred in 1060 (10.5%) eyes, Sands of Sahara syndrome occurred in 232 (2.3%) eyes, interface infection responsive to treatment occurred in 4 (0.04%) eyes, and epithelial ingrowth occurred in 1 (0.01%) eye.

CONCLUSIONS: LASIK is a safe and effective method for the treatment of myopia. [J Refract Surg. 2005;21(Suppl):S633-S635.]
Clinical Outcomes of CATz Versus OPDCAT
Authors: Pop Mihai , Bains Harkaran S
Published: December 2019

ABSTRACT

PURPOSE: To compare refractive outcomes, wavefront outcomes, and corneal asphericity indices (Q values) for patients treated with wavefront-guided or topography-guided custom ablations using the NIDEK Advanced Vision Excimer Laser System (NAVEX).

METHODS: A total of 196 eyes of 98 patients underwent wavefront-guided or topography-guided LASIK. A contralateral study of 28 eyes of 14 patients who underwent customized aspheric treatment zone (CATz) ablation in one eye and optical path difference customized aspheric treatment (OPDCAT) in the fellow eye comprised one part of the study. The second part of the study was a retrospective review of myopic LASIK using CATz in 84 eyes and LASIK using OPDCAT in 84 eyes. In the CATz-treated eyes, the preoperative mean spherical equivalent refraction was -4.06±1.69 diopters (D). In OPDCAT-treated eyes, the preoperative mean spherical equivalent refraction was -3.67±2.17 D.

RESULTS: In the CATz-treated eyes, 95% of eyes achieved ≥20/20 best spectacle-corrected visual acuity (BSCVA) with 15% gaining lines of BSCVA. In the OPDCAT-treated eyes, 94.5% of eyes achieved ≥20/20 vision with 4.5% gaining lines of BSCVA. The difference in lines gained between CATz and OPDCAT in the retrospective component was statistically significant (P<.005). OPDCAT-treated eyes showed a statistically significant worsening in OPD root-mean-square (OPD-RMS), higher order wavefront error, and corneal asphericity (P<.005) compared to preoperative in the retrospective portion of the study. In the contralateral arm of the study, OPD-RMS value was significantly higher (P<.005) in the OPDCAT eyes than the fellow CATz-treated eyes. OPDCAT-treated eyes show a larger change in the Strehl ratio compared to the CATz-treated eyes (P<.005).

CONCLUSIONS: The refractive outcomes were excellent and showed no clinically significant difference between CATz and OPDCAT treatments. The higher induction of aberrations with the OPDCAT ablations may be due to the fact that these treatments are based on Zernike polynomials to drive the ablation. [J Refract Surg. 2005;21(Suppl):S636-S639.]
The Thin-Flap LASIK Technique
Authors: Dougherty Paul J
Published: December 2019

ABSTRACT

PURPOSE: To determine if LASIK using a 130-µm microkeratome head (thin-flap LASIK) is as visually effective and safe as when using a 160-µm head.

METHODS: A study was performed comparing postoperative day 1 uncorrected visual acuity (UCVA) and flap complications in eyes undergoing myopic LASIK with a 130-µm head versus a 160-µm head using the BD K-3000 microkeratome (BD Ophthalmic Systems, Waltham, Mass).

RESULTS: The mean preoperative myopia in the 155 eyes of 80 patients in the 130-µm head group was -5.00±2.53 diopters (D) compared to -3.78±1.73 D in the 279 eyes of 148 patients in the 160-µm head group. The groups were otherwise similar in terms of age, preoperative cylinder, and best spectacle-corrected visual acuity. The geometric mean postoperative day 1 UCVA was 20/25 in the 130-µm head group compared to 20/26 in the 160-µm head group. The only flap complication in the series was a single partial flap in the 160-µm head group.

CONCLUSIONS: LASIK with a 130-µm head (thin-flap LASIK) is as visually effective and safe as when using a 160-µm head with the BD K-3000 microkeratome. [J Refract Surg. 2005;21(Suppl):S650-S654.]
A Comparison of Higher Order Aberrations Following Implantation of Four Foldable Intraocular Lens Designs
Authors: Martin Robert G , Sanders Donald R
Published: December 2019

ABSTRACT

PURPOSE: To determine the higher order aberrations following implantation of four foldable intraocular lens (IOL) designs.

METHODS: One hundred twenty-two eyes were randomly assigned to undergo implantation with one of four foldable IOL designs ? Collamer (STAAR Surgical, Monrovia, Calif), plate haptic silicone (STAAR Surgical), AcrySof (Alcon, Ft Worth, Tex), or the Sensar (Advanced Medical Optics, Santa Ana, Calif). All enrolled eyes underwent wavefront assessment using the Tracey Visual Function Analyzer (Tracey Technologies, Houston, Tex).

RESULTS: Preoperatively, no significant differences were noted in higher order aberrations between the four lens groups. No significant differences were noted among the plate haptic silicone, Sensar, or AcrySof lenses at 1 week or 1 month postoperatively, or among the Collamer, plate haptic silicone, or Sensar lenses, with regard to total higher order aberrations, although differences were observed in individual aberration terms. At 1 week and 1 month postoperatively, the Collamer IOL had significantly less higher order aberrations than the AcrySof lens (P<.01). Significantly less third and fourth order aberrations, coma, trefoil, spherical aberration, and tetrafoil were observed postoperatively with the Collamer than the AcrySof IOL. There were no parameters where the AcrySof had significantly less optical aberrations than the Collamer.

CONCLUSIONS: The Collamer IOL design is associated with fewer higher order aberrations than the AcrySof lens. [J Refract Surg. 2005;21:716-721.]
Reverse Geometry Contact Lens Fitting After Corneal Refractive Surgery
Authors: Martin Raul , Rodriguez Guadalupe
Published: December 2019

ABSTRACT

PURPOSE: To describe reverse geometry rigid gas permeable (RGP) contact lens fitting in eyes with irregular surface induced by complications after myopic corneal refractive surgery.

METHODS: Reverse geometry RGP contact lenses were fit in nine eyes that underwent myopic corneal refractive surgery and experienced a reduction in best spectacle-corrected visual acuity (BSCVA) Snellen lines postoperatively.

RESULTS: Comparing the BSCVA with contact lenses, 5 (55.6%) eyes improved >2 lines of BSCVA, 2 (22.2%) eyes improved 1 line, and 2 (22.2%) eyes maintained the same BSCVA as the one eye with spectacles (P<.004). No eye lost lines of BSCVA. All patients reported excellent tolerance and subjective visual quality with the contact lenses. The mean time of contact lens wear was 10.44?0.88 hours per day (95% confidence interval, 9.76 to 11.12).

CONCLUSIONS: Reverse geometry RGP contact lens fitting is effective in correcting surgically induced irregular surfaces with improved visual acuity and comfortable wear. These lenses may be the best choice in cases in which surgical retreatment is unfeasible or undesirable. [J Refract Surg. 2005;21:753-756.]
Reactivation of Ocular Toxoplasmosis After LASIK
Authors: Barbara Adel , Shehadeh-Masha'our Raneen , Sartani Gil , Garzozi Hanna J
Published: December 2019

ABSTRACT

PURPOSE: To report a reactivation of ocular toxoplasmosis after LASIK.

METHODS: Case report of a 34-year-old man who underwent bilateral LASIK. The posterior segment examination revealed an old toxoplasmosis scar in the retinal periphery of the right eye.

RESULTS: Uncorrected visual acuity improved postoperatively, and the patient was satisfied. However, 52 days after the procedure, he complained of loss of visual acuity in his right eye. Examination revealed signs of anterior uveitis, vitreitis, and active chorioretinal lesion satellite of the old toxoplasmosis scar. The patient was treated with a multidrug regiment with resolution of the vitreous and lesion activity.

CONCLUSIONS: Toxoplasmosis reactivation may develop after LASIK. [J Refract Surg. 2005;21:759-761.]
The Effects of Automated Registration on Aberration Measurement With the LADARWave Aberrometer
Authors: Steinert Roger F
Published: December 2019

ABSTRACT

PURPOSE: To evaluate the effects of automating the registration process for wavefront measurement using the LADARWave aberrometer. Measures of interest include accuracy, repeatability, and speed of measurement.

METHODS: Five separate registration images were collected for each of eight eyes of four individuals with varying iris color using the LADARWave aberrometer. Technicians manually aligned the images and the autoregistration feature was used to align the same images. Time, accuracy, and repeatability of the alignment were measured using objective techniques. The potential effect on positional error was evaluated using a retrospective reprocessing of LADARWave data from an existing sample dataset.

RESULTS: Auto registration was the fastest method of alignment, from five to seven times faster than manual registration. It was also the most consistent, with the lowest pupil/limbus offset error (45 ???). Technicians averaged 48 to 91??m. The differences in wavefronts used to generate the composite wavefront image for surgery export were 18% lower with auto registrai ion.

CONCLUSIONS: The auto registration feature of the LADARWave aberrometer not only removes inter-technician variability, but reduces the time to perform image alignments and improves the consistency of the alignments. This helps reduce errors related to wavefront position, potentially improving outcomes. [J Refract Surg. 2005;21:S769-S771.]
Technological Improvements With the Alcon LADAR 6000 Excimer Laser Platform
Authors: Krueger Ronald R
Published: December 2019

ABSTRACT

PURPOSE: To outline the technological improvements seen in the new Alcon U\DAR 6000 laser.

METHODS: New LADAR 6000 features can be categorized into three areas: automation, speed, and control.

RESULTS: Automation features include auto-registration, specialized illumination, scleral vessel registration, and automated prompting. Speed features include a faster ablation rate and less intensive maintenance. Control features include auto registration, a better graphic user interface, and an improved workspace.

CONCLUSIONS: The technological improvements of the LADAR 6000 help eliminate the variability of measurement, alignment, and delivery needed to optimize custom laser vision correction outcomes. [J Refract Surg. 2005;21:S775-S780.]
Postoperative Wavefront Analysis and Contrast Sensitivity of a Multifocal Apodized Diffrattive IOL (ReSTOR) and Three Monofocal IOLs
Authors: Rocha Karolinne Maia , Chalita Maria Regina , Souza Carlos Eduardo B , Soriano Eduardo S , Freitas Lincoln L , Muccioli Cristina , Belfort Rubens
Published: December 2019

ABSTRACT

PURPOSE: To compare visual acuity, total and high order wavefront aberrations (coma, spherical aberration, and other terms of high order aberration), and contrast sensitivity in 105 eyes implanted with 4 different types of intraocular lenses (IOLs) (1 multifocal apodized diffractive IOL and 3 monofocal IOLs).

METHODS: A prospective study comparing four types of IOLs (Alcon ReSTOR [50 eyes], Alcon Acrysof MA30AC [20 eyes], Alcon Acrysof SA60AT [20 eyes], and Mediphacos Acqua IOL [15 eyes]) was carried out. All eyes were targeted for emmetropia. Complete ophtha lmological examination, including uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), contrast sensitivity (Pelli- Robson chart), and wavefront analysis, was performed 2 months postoperatively.

RESULTS: All eyes in all groups had BSCVA ≥20/32 postoperatively. Mean total aberration root-meansquare (RMS) values were: 0.72?0.25 µm (ReSTOR), 0.94?0.26 µm (MA30), 0.84?0.23 µm) (SA60), and 2. 04 ?0.77 µm (Acqua). Mean higher order aberration values were: 0.35?0.15 µm (ReSTOR), 0.41 ± 0.12 µm (MA30), 0.43±0.13 µm) (SA60), and 0.85±0.50 µm) (Acqua). The Acqua IOL showed statistically significant more total and higher order aberrations when compared with the other IOLs (P<.05). The ReSTOR IOL showed statistically significant less induction of spherical aberration when compared to the monofocal IOLs (P<.05). Mean contrast sensitivity values were: 1.64 ?0.08 (ReSTOR), 1.72?0.08 (MA30), 1.70?0.07 (SA60), and 1.65?0.11 (Acqua).

CONCLUSIONS: Different types of IOLs resulted in measurably different postoperative higher order aberration patterns. The multifocal apodized diffractive IOL (ReSTOR) induced significantly less spherical aberration compared to the monofocal IOLs. Contrast sensitivity revealed better values with MA30 and SA60 IOLs when compared to ReSTOR. The integration of wavefront technology in evaluating Pseudophakie patients represents a step towards better understanding and analyzing postoperative visual quality. [J Refract Surg. 2005;21: S808-S812.]
A Title Page of Michael Praetorius
Authors: Holman Peter
Published: December 2019

The well-known title page used by Michael Praetorius for several of his publications provides a starting-point for a discussion of the way large-scale music was directed in early seventeenth-century Germany. The practice of depicting composers with rolls of paper is discussed, as is the nature of seventeenth-century time-beating and how it differed from modern conducting.
Michael Praetorius’s Variable Opinions on Performance
Authors: Kite-Powell Jeffery
Published: December 2019

This article presents Praetorius’s wide-ranging opinions on performance practice, including what distinguishes a good composition from an inferior one, how performance forces are to be selected and deployed, and which performance practices are acceptable and which are to be avoided. His stance varies from laudatory and supportive to censorious and disapproving. These and other issues are presented in both English and the original German, and offer suggestions on how to orchestrate a polychoral work today, including reference to recorded media.
Italian Musical Culture and Terminology in the Third Volume of Michael Praetorius’s Syntagma musicum (1619)
Authors: Toffetti Marina
Published: December 2019

From the third volume of Michael Praetorius’s Syntagma musicum one receives the impression that, according to its author, only those who were able to compose, play or sing ‘all’italiana’ (in the Italian manner) were considered culturally up-to-date. This treatise can therefore be seen as a mirror reflecting the way in which Italian music was perceived north of the Alps in the second decade of the seventeenth century. The present article, based on a re-reading of the third volume of Syntagma musicum, shows how in the early decades of the seventeenth century the circulation and the assimilation of Italian musical culture and terminology was far-reaching in the German-speaking countries, contributing to the genesis of a pan-European musical style and terminology.
Praetorius Versus Zarlino: The Question of Modes
Authors: Sukljan Nejc
Published: December 2019

This article deals with the question of modes as it is discussed in Gioseffo Zarlino’s Istitutioni harmoniche and Michael Praetorius’s Syntagma musicum. First, Gioseffo Zarlino’s adoption of Heinrich Glarean’s system of twelve modes is presented, along with the changes he introduced. Gioseffo Zarlino’s system is then compared to that of Michael Praetorius.
Reconstructing Lost Instruments: Praetorius’s Syntagma musicum and the Violin Family c. 1619
Authors: Zeller Matthew
Published: December 2019

Michael Praetorius’s De organographia and Theatrum instrumentorum provide valuable clues that contribute to a new understanding of the violin family c. 1619, many surviving examples of which are reduced in size from their sixteenth- and seventeenth-century dimensions. The record of surviving instruments – especially those of the Amati family – alongside metrologic, documentary and iconographic evidence shows that Michael Praetorius describes a large instrument conforming remarkably well to the original dimensions of the basso da braccio (violoncello), as well as furnishing an excellent scale representation of the violin family as it was at the time of these works’ publication and an accurate tuning scheme.
La sombra omeya. Córdoba y los almohades en la segunda mitad del siglo VI/XII
Authors: Blanco-Guzmán Rafael
Published: December 2019

La arqueología ha revelado recientemente la existencia de una importante revitalización urbana en Córdoba durante el Califato Almohade, apenas tratada hasta ahora por la historiografía, centrada principalmente en su pasado omeya. Por un lado, se ha observado una importante inversión del poder almohade en elementos defensivos y palatinos, acaso por tratarse en estas fechas de un centro fundamental en la conceptualización histórica de al-Andalus y en la lucha contra los reinos cristianos; por otro, se ha documentado un importante crecimiento orgánico y privado extramuros. Todo ello coincidió con su elección como capital andalusí en 557/1162 por ‘Abd al-Mu’min, lo que suponía un hito fundamental para la legitimación de su nuevo califato. Tras su muerte pocos meses después, Abū Ya‘qūb Yūsuf hizo regresar la corte a Sevilla, creando un importante cambio de rumbo en la política almohade que no afectó al resurgir urbano de la antigua sede omeya. En realidad, Córdoba seguiría muy presente en la mentalidad colectiva andalusí durante el gobierno almohade, manteniéndose como referente principal del esplendor pasado y como núcleo esencial de la tradición mālikī.
Mal tiempo en Bagdad: al-Ṭurṭūšī y el “eclipse” de 478/1085-1086
Authors: Wasserstein David J.
Published: December 2019

El artículo analiza un pasaje autobiográfico de la vida de al-Ṭurṭūšī (c. 451/1059-520/1126, o Ŷumādā al-awwal 525/abril de 1131) contenido en el Siyar A‘lām al-Nubalā’ de al-Ḏahabī (673/1274-748/1348). El texto informa sobre una notable serie de fenómenos meteorológicos acaecidos durante la visita de al-Ṭurṭūšī a Bagdad en 478/1085-86. Fierro interpretó la historia como la descripción de un eclipse y como el origen del cambio de al-Ṭurṭūšī hacia el ascetismo, paralela a una historia similar sobre el anterior Muḥammad Iḅn Waḍḍāḥ. Aquí demuestro, basado en registros astronómicos, que no hubo eclipse en aquel tiempo en Bagdad, por lo que en consecuencia, lo que al-Ṭurṭūšī experimentó no pudo haber sido tal. Además, al-Ṭurṭūšī tampoco lo entendió así. No pudo, por lo tanto, haber sido la causa de su vuelta al ascetismo. La descripción apunta más bien a una tormenta de polvo o simún. Por lo tanto, no hay vínculo alguno, literario o de otro orden, entre este punto de la vida de al-Ṭurṭūšī y el de Muḥammad Iḅn Waḍḍāḥ.
Efecto de la precipitación de fases metaestables en las propiedades termofísicas y mecánicas de la aleación EN AW-6082
Authors: Stamenković Uroš , Ivanov Svetlana , Marković Ivana , Balanović Ljubiša , Gorgievski Milan
Published: December 2019

En este trabajo se estudia el efecto de la precipitación de fases metaestables sobre las propiedades termofísicas y mecánicas de la aleación EN AW-6082. Después del tratamiento con solución sólida y el enfriamiento rápido en agua helada, las muestras se sometieron a análisis DSC e investigación térmica con el objetivo de definir temperaturas óptimas para el recocido isocrónico. El recocido isocrónico se realizó a temperaturas que oscilan entre 160-330 °C durante dos tiempos de recocido: 30 y 60 min. La conductividad eléctrica, la dureza, la microdureza y las propiedades estructurales se investigaron durante el tratamiento de envejecimiento isocrónico. Las propiedades mecánicas alcanzaron valores máximos durante el envejecimiento a 230 °C durante 30 min y a 220 °C durante 60 min, respectivamente. La conductividad eléctrica aumentó gra-dualmente con un aumento en la temperatura de envejecimiento debido a la precipitación de la solución sólida. Las investigaciones microestructurales realizadas por SEM-EDS confirmaron la existencia de fases precipitadas y su distribución en todas las muestras investigadas.
Influencia de la deformación previa sobre el endurecimiento por precipitación en una aleación de Cu-Ni-Si
Authors: Donoso Eduardo , Diánez Mª Jesús , Criado José M.
Published: December 2019

Los efectos de la deformación previa sobre los procesos de precipitación en una aleación de Cu-2,8 Ni-1,4 Si (at.%) fueron estudiados utilizando calorimetría diferencial de barrido (DSC), microscopía electrónica de transmisión (TEM) y medidas de microdureza. Las curvas calorimétricas muestran la presencia de una reacción exotérmica atribuido a la formación de precipitados de δ-Ni2Si en la matriz de cobre, lo cual fue confirmado mediante TEM. Además, sse puede observar que la temperatura del máximo del pico de DSC decrece con el aumento de la deformación previa a los tratamientos de envejecimiento. Las energías de activación calculadas para la precipitación de δ-Ni2Si, mediante el método de Kissinger, resultaron similares a aquellas calculadas mediante una función de Arrhenius, a partir del máximo de endurecimiento de la matriz debido al tratamiento de envejecimiento (saturación de la dureza durante el envejecimiento isotérmico). El análisis de las medidas de microdureza en conjunto con las curvas calorimétricas y las micrografías TEM permiten corroborar, por una parte que la formación de la fase δ-Ni2Si, durante los tratamientos de envejecimiento, son los responsables del endurecimiento de la matriz de cobre, y por otra que la deformación previa al tratamiento de envejecimiento inhibe parcialmente la formación de los precipitados.
Expressions picturales de la vanité au xviie siècle
Authors: Heck Michèle-Caroline
Published: December 2019

Les représentations picturales de la Vanité occupent au xviie siècle une place particulière. Elles s’inscrivent dans une double problématique qui tient compte d’une réflexion renouvelée sur la mort, du rapprochement du champ du religieux et du profane, dans le contexte du transfert de signification de la figure humaine à l’objet dans les natures mortes. Simples ou plus complexes, les natures mortes témoignent de la diversité de sens de cette notion. Les enjeux sont d’ordre religieux, moral, mais ils proposent surtout une nouvelle conception de l’homme. Ainsi, la Vanité ne se borne-t-elle pas à la représentation de la mort sous forme d’un crâne, mais s’insinue également dans les représentations des cinq sens ou des livres, et évoque l’attachement aux biens de ce monde.
Green Logistics Practices and Sustainable Business Model
Authors: Karia Noorliza
Published: December 2019

This chapter presents a broad introduction to the knowledge of green logistics in a practical manner; definition and dimensions of green logistics practices; factors of green practices and their roles and impacts. Given the importance of logistics in global economic and increasing concern in environmental sustainability, this chapter looks at the work model in green leadership for fostering competitiveness and sustainability development in the world. It will look at how green attributes can be transformed into the practical lives of today's leaders, and take away the essence, insights, and tools of green leadership, and step up to the next level as a true firm, definitely from a logistics service provider perspective.
To Lend or Not to Lend
Authors: Mach Traci L. , Carter Courtney M. , Slattery Cailin R.
Published: December 2019

The current paper examines loan-level data from Lending Club to look at peer-to-peer borrowing by small businesses. We begin by looking at characteristics of loan applications that were and were not funded and then take a more in-depth look at funded applications. Summary statistics show an increasing number of small business loan applications over time. Beginning in 2010—when consistent measures of loan purpose were recorded for all applications—loan applications for small businesses were on average less likely than loans for other purposes to have been funded. However, logistic regression results that control for the quality of the application show that, holding all else constant, applications for a loan for a small business were almost twice as likely to have been funded as loans for other purposes. Focusing on funded applications, we note that funded business loans were slightly larger on average than loans funded for other purposes but paid similar interest rates. However, relative to small business loans from traditional sources, peer-to-peer small business borrowers paid an interest rate that was about two times higher. Regression results that control for application quality show that peer-to-peer loans for small businesses were charged almost a percentage point interest rate premium over non-business loans. Logistic regression results that look at loan performance indicate that loans for small businesses were much more likely to be delinquent or charged off.
Design Methods for Decision Support Systems
Authors: Khatun Madhury , Miah Shah J.
Published: December 2019

This article reviews methods to the development of a decision support system (DSS) solution for small business owners/managers. The main objective of designing the DSS artefact is to support the strategic decision-making for achieving competitive advantages in the business-to-consumer (B2C) e-commerce environment. Many researchers in the DSS domain utilised various methods to design of information systems (IS) artefact, mostly intended for large businesses. Researchers have paid much attention to the business environment as a knowledge source for DSS design and development for the small business strategic decision support needs. User-centred design (UCD) principles were adopted for DSS development. Prior a novel DSS development, multiple case studies were carried out for understanding the user needs and system requirements. Also, knowledge was sourced from the external business environment via the analysis of small business website features against their overseas competitors. The findings suggested developing a DSS solution for small business needs.
Towards a Hybrid MAS Organizational Model
Authors: Abbas Hosny Ahmed , Shaheen Samir
Published: December 2019

The organizational aspects are currently getting a great attention within the multi-agent systems (MAS) community. The motivation towards this trend is finding a way to handle the increasing complexity and distribution of modern agent-based applications using higher order abstractions such as agent organizations. It is a transition from concerning the micro level (individual agents) to concerning the macro level (the whole system) to handle complexity. A large number of MAS organizational models can be found in MAS literature. Some of them adopt the ACMAS (Agent-Centered MAS) viewpoint and others adopt the OCMAS (Organizational-Centered MAS) viewpoint. Each of the ACMAS and OCMAS viewpoints has its advantages and disadvantages; therefore, combining them into a hybrid model is expected to give us the chance to take benefit of their advantages and avoid their disadvantages. This chapter presents our recent work towards the conceptual design of a hybrid MAS organizational model that combines both of the ACMAS and OCMAS viewpoints.
Adoption of Online Marketing for Service SMEs with Multi-Criteria Decision-Making Approach
Authors: Ocampo Lanndon , Alarde Rosalin Merry Berdin , Kilongkilong Dennis Anthony , Esmero Antonio
Published: December 2019

This chapter attempts to fill in the gap of evaluating the viability of adopting online marketing for small and medium enterprises (SMEs) in service industries. As SMEs are generally characterized by shortage of resources, the use of online marketing strategies is apparently difficult. However, the current landscape of competition among SMEs in a global market economy prompts the necessity of adopting online marketing. With these, the decision-making process of SMEs in this area becomes complex and the decisions must integrate complex and interrelating criteria and constructs in order to provide a more holistic solution. Thus, this work adopts a multi-criteria decision-making (MCDM) method particularly the analytic network process (ANP) in order to evaluate the practicability of using online marketing for service SMEs. It becomes highly relevant as it provides significant insights to decision-makers in SMEs regarding the use of online marketing strategy. The contribution of this chapter lies in the application of MCDM in evaluating viability of online marketing in service SMEs.
Optimizing Virtual Communities in Tourism to Facilitate Development of Small and Medium-Sized Enterprises
Authors: Yordanova Silvena Dencheva
Published: December 2019

The chapter presents the essence of online/virtual travel communities and examines their current significance for SMEs. It presents types and characteristics as well as the most popular virtual travel SME communities and discusses ways of optimizing the development of SMEs by applying a strategy of virtual communities by selected hospitality SMEs. An eight step strategy to implement virtual travel communities by SMEs is elaborated. One of the main findings of the author is that virtual travel communities can be very useful for optimizing the development of SMEs by supporting all the stages in the decision-making process, focusing on pre-planning, making the decision and after the tourist and business visit stage. In order to understand how virtual travel community can optimize the development of SMEs, the author discusses tools for measuring the effectiveness of social media. Both future research directions and a conclusion are outlined.
A Framework for Research on Information Technology Governance in SMEs
Authors: Bergeron François , Croteau Anne-Marie , Uwizeyemungu Sylvestre , Raymond Louis
Published: December 2019

The need to effectively manage IT resources such that they enhance the business value of firms makes IT Governance (ITG) an important issue for both IS researchers and practitioners. The purpose of this paper is to build a conceptual framework for ITG in small and Medium-Sized Enterprises (SMEs). The authors first analyze the main theories applied in ITG research, and confront them with the specificities of SMEs. The authors then highlight the limits of those theories in SMEs context and discuss adaptations needed or alternative theories in such context. The resulting framework is then applied to generate a set of six research propositions on ITG in SMEs.
Impact of Mobile Money Transfer on the Education Sector in Sub-Saharan Africa
Authors: Juma Albert
Published: December 2019

Digitalization of payments related to education has played a significant role in driving the fourth agenda of the Sustainable Development Goals (SDG) aimed at providing free, equitable, and quality primary and secondary education to children by 2030. Since the launch of mobile money transfer (MMT) technologies by Safaricom in Kenya in 2007, many providers have developed a range of services to ensure efficient, transparent, and sustainable means of paying for school and college fees. This has led to enhanced teacher-student interaction times, reduced absenteeism, improved security in handling money, and made it easier for families to save, plan, and educate their children. This chapter reviews key success cases of countries and institutions that have digitalized payments and other education services to empower disadvantaged communities.
Preparation and Characterization of Polypropylene and Unsaturated Polyester Resin Filled with Jute Fiber
Authors: Keya Kamrun N. , Kona Nasrin A. , Hossain Md. Sahadat , Razzak Md. , Islam Md. Naimul , Khan Ruhul A.
Published: December 2019

Jute fabrics reinforced Polypropylene (PP) matrix composite was fabricated by compression molding and Unsaturated Polyester Resin (UPR) matrix composites were also fabricated by hand lay-up technique. The fiber content of the composites was 40% by weight. Mechanical properties between two types of composites were compared. Tensile Strength (TS), Tensile Modulus (TM), Elongation at break (Eb%) , and Impact Strength (IS) of the jute fabrics/PP composites were found to be 47 MPa, 1.2 GPa, 13% and 8 kg/cm, respectively. On the other hand, TS, TM, Eb%, and IS of the jute fabrics/UPR composite were found to be 43 MPa, 1.3 GPa, 10% and 6 kg/cm, respectively. It was found that both composites showed almost similar mechanical properties. After tensile testing, fracture sides of both types of the composites were studied by Scanning Electron Microscope (SEM) and the results revealed poor fiber matrix adhesion for jute fabrics with PP and UPR. The fabricated composites became partly biodegradable because of jute (natural fiber) and mechanical properties of both types of composites showed promising results for commercial applications.
Damping Optimization in Seismic Isolation Systems
Authors: Rutman Yuri L. , Ostrovskaya Nadezhda V.
Published: December 2019

To protect civil buildings, industrial facilities and bridges against earthquakes and explosions, various seismic isolation systems (SIS) are used. SISs always include dissipative elements that dissipate energy transmitted to the protected object (PO) during seismic effect, operation of which is based on the elastic-plastic deformation of special structures — elastic-plastic dampers (PD). The paper proposes a method for selecting the optimum design parameters of elastic-plastic dampers in SISs. The problem is solved upon specifying an ensemble of random seismic effects. A suite of artificial accelerograms obtained by statistical modeling is used as a stream of events supplied to the right side of motion equations. Dispersion of PO absolute accelerations was chosen as an optimization criterion. After linearization of the model, the dimensionless damping coefficient introduced into the dynamic model according to the Voigt–Bock hypothesis was taken as a variable parameter. Relationship between the selected optimization criterion and the theory of seismic risk of V.V. Bolotin has been established. It is shown that optimization of the damping coefficient reduces the seismic risk by 1.5–1.8 times. A method has been developed for transition from the optimum damping coefficient to design parameters of elastic-plastic dampers that implement this coefficient. Analytical dependences have been obtained enabling to set those parameters easily.
Application of Modern Materials in Conditions of Complete Reconstruction of Existing Buildings
Authors: Babajanyan Grigor
Published: December 2019

At the present stage of urban fabric formation, the problem of adapting existing buildings to modern socio-economic conditions and functional needs is very important. In the conditions of constraint of already existing urban development, the issue of reconstruction and renovation of existing buildings becomes particularly relevant. There are frequent examples of new additions and superstructures over the “historical foundation”. In the light of the solution of functional and especially constructive tasks, the choice of building materials becomes extremely important. Examples of reconstructed buildings have been considered, it has been revealed that the most used in the reconstruction of modern materials for today are glass and composite panels. Since the reconstructed buildings are mainly built of stone or brick, the building and composite panels with color and texture features contrast with the old masonry, thereby highlighting and complementing it. The quality and characteristics of the above mentioned materials, the advantages that they have in comparison with traditional stone and concrete, and the great possibilities of obtaining a variety of structures and facade plastics have been analyzed.
Harmonic Maass forms associated to real quadratic fields
Authors: Charollois Pierre , Li Yingkun
Published: December 2019

In this paper, we explicitly construct harmonic Maass forms that map to the holomorphic weight 1 theta series associated by Hecke to odd ray class group characters of real quadratic fields. From this construction, we give precise arithmetic information contained in the Fourier coefficients of the holomorphic part of the harmonic Maass form, establishing the main part of a conjecture of the second author.
Characteristics of Flat-Wall Impinging Spray Flame and Its Heat Transfer under Diesel Engine-Like Condition: Effects of Injection Pressure, Nozzle Hole Diameter and Impingement Distance
Authors: Mahmud Rizal , Kurisu Toru , Akgol Onur , Nishida Keiya , Ogata Yoichi
Published: December 2019

Substantial amount of fuel energy input is lost by heat transfer through combustion chamber walls in the internal combustion engines. Thus, these heat losses account for reduced thermal efficiency, in that spray-wall impingement plays a crucial role in Direct Injection diesel engines. The objective of this study is to investigate the mechanism of the heat transfer from the spray/flame to the impinging wall under small diesel engine-like condition and how the spray characteristics are affected with regards to effect of injection pressure, nozzle hole diameter and impingement distance. The experiment results showed that injection pressure was predominant factor on spray-wall heat transfer.
Control of the Distillation Curve of Biodiesel Fuel by Cross-Metathesis Reaction Based on Fatty-Acid Composition
Authors: Kawasaki Kiyoshi , Yamane Koji , Umeno Ryohei
Published: December 2019

Biodiesel fuel (Fatty acid methyl esters: FAME) have lower volatility than petro-diesel fuel due to the larger molecular size of FAME. Recent studies report that the distillation temperature of biodiesel fuel can be lowered by the cross-metathesis reaction with short-chain olefin using ruthenium catalyst. In this study, the effect of cross-metathesis reaction conditions on the distillation characteristics of reformulated biodiesel fuel is investigated to reveal the reaction conditions for fitting the distillation curve of biodiesel fuels to that of petro-diesel fuel. Furthermore, the reactivity of typical biodiesel fuels such as RME (rapeseed oil), SME (soybean oil), and WME (waste cooking oil) for cross-metathesis reaction were examined to reveal the reaction conditions appropriate for their fatty-acid compositions.
Prediction of Cavitation Erosion Intensity Using Large-Scale Diesel Nozzles
Authors: Kambara Motoya , Aochi Takanobu , Arikawa Fumiaki , Hijima Toshiaki , Serizawa Kazufumi
Published: December 2019

In the field of heavy-duty diesel engines, which require lifetime durability and high fuel efficiency, there is a growing demand for increased injection pressure and increased flow rate inside injection holes. This trend makes it important to prevent cavitation erosion of injector nozzles. This paper aims to clarify the relation between cavitation behavior and erosion damage experimentally by visualizing the flow inside diesel nozzles and to establish a new method for predicting cavitation erosion. To visualize internal flow, authors used the large-scale transparent nozzle whose Reynolds number and Cavitation number were matched with those of the actual real-size nozzle. Direct observation showed that the form of the cavitation changed from string-type cavitation to film-type cavitation with increasing needle lift. In addition, comparison between the locations where cavitation bubbles collapse and the locations where erosion occurs suggested that collapse of the film-type cavitation at high needle lift contributed significantly to the erosion damage. Furthermore, it is found that the location and intensity of erosion can be predicted by calculating the local quantity of film-type cavitation collapse.
A study of Measurement for Oil Film at the Bearing of the Small End of Diesel Engine Connecting Rod
Authors: Suzuki Shotaro , Yamada Shota , Ito Akemi
Published: December 2019

Downsizing and slowing down of engine speed reduce mechanical losses and improve fuel economy. However, they exacerbate lubrication condition. The oil film thickness of the bearing of the small end of the connecting rod, which was one of the sliding surfaces with the severest lubrication condition in a diesel engine, was measured in this study to clarify the lubrication condition. Optical fibers were embedded in the bearing, and oil film was measured by means of the laser induced fluorescence method. It was found that oil film thickness was affected combustion gas pressure and distortion of the piston pin.