bluuebunny/crossref_metadata_2025 huggingface dataset:
High Incidence of Lysogeny in the Oxygen Minimum Zones of the Arabian Sea (Southwest Coast of India)
Authors: Parvathi Ammini , Jasna Vijayan , Aparna Sreekumar , Pradeep Ram Angia Sriram , Aswathy Vijaya Krishna , Balachandran Kizhakkeppat K. , Muraleedharan Kallungal Ravunnikutty , Mathew Dayana , Sime-Ngando Telesphore
Published: October 2018

Though microbial processes in the oxygen minimum zones (OMZs) of the Arabian Sea (AS) are well documented, prokaryote-virus interactions are less known. The present study was carried out to determine the potential physico-chemical factors influencing viral abundances and their life strategies (lytic and lysogenic) along the vertical gradient in the OMZ of the AS (southwest coast of India). Water samples were collected during the southwest monsoon (SWM) season in two consecutive years (2015 and 2016) from different depths, namely, the surface layer, secondary chlorophyll a maxima (~30–40 m), oxycline (~70–80 m), and hypoxic/suboxic layers (~200–350 m). The high viral abundances observed in oxygenated surface waters (mean ± SD = 6.1 ± 3.4 × 106 viral-like particles (VLPs) mL−1), drastically decreased with depth in the oxycline region (1.2 ± 0.5 × 106 VLPs mL−1) and hypoxic/suboxic waters (0.3 ± 0.3 × 106 VLPs mL−1). Virus to prokaryote ratio fluctuated in the mixed layer (~10) and declined significantly (p < 0.001) to 1 in the hypoxic layer. Viral production (VP) and frequency of virus infected cells (FIC) were maximum in the surface and minimum in the oxycline layer, whereas the viral lysis was undetectable in the suboxic/hypoxic layer. The detection of a high percentage of lysogeny in suboxic (48%) and oxycline zones (9–24%), accompanied by undetectable rates of lytic viral infection support the hypothesis that lysogeny may represent the major survival strategy for viruses in unproductive or harsh nutrient/host conditions in deoxygenated waters.
Colloid Transport in a Single Fracture–Matrix System: Gravity Effects, Influence of Colloid Size and Density
Authors: Bagalkot Nikhil , Kumar G. Suresh
Published: October 2018

A numerical model was developed to investigate the influence of gravitational force on the transport of colloids in a single horizontal fracture–matrix system. Along with major transport phenomena, prominence was given to study the mass flux at the fracture–matrix interface, and colloid penetration within the rock matrix. Results suggest that the gravitational force significantly alters and controls the velocity of colloids in the fracture. Further, it was shown that the colloid density and size play a vital part in determining the extent that gravity may influence the transport of colloids in both fracture and rock matrix. The mass flux transfer across the fracture–matrix interface is predominantly dependent on the colloidal size. As large as 80% reduction in penetration of colloids in the rock matrix was observed when the size of the colloid was increased from 50–600 nm. Similarly, the farther the density of colloid from that of the fluid in the fracture (water), then the higher the mitigation of colloids in the fracture and the rock matrix. Finally, a non-dimensional parameter “Rock Saturation Factor” has been presented in the present study, which can offer a straightforward approach for evaluating the extent of penetration of colloids within the rock matrix.
The Identification of Factors Affecting the Use of Pressurized Irrigation Systems by Farmers in Iran
Authors: Momvandi Abdullah , Omidi Najafabadi Maryam , Hosseini Jamal F. , Lashgarara Farhad
Published: October 2018

Climate change and water scarcity are the most important challenges of the agricultural sector, and pressurized irrigation systems (PISs) are one of the most significant ways to improve agricultural water productivity. The main purpose of this research was to identify the factors affecting the use of PISs by farmers. The statistical research population was a total of 2396 Iranian model farmers. The Cochran formula was used to determine the number of statistical samples. Accordingly, this comprised 331 people. The methodology of the study was mixed method research. The structural equation modeling technique, Mann–Whitney U, and Kruskal–Wallis tests were used to test the hypotheses. The results showed that the personal characteristics, tendency, attitude, self-efficacy, subjective norms, governmental support, environmental tensions, and technological features were the most important factors which influenced the farmers. It was found that all of these variables had a positive and significant relationship with the using of PISs by farmers, and they were able to predict 52% of the behavioral changes (R2) of the farmers. Among these variables, the attitude, with a path coefficient (β) of 0.48, had the highest impact on the using of PISs by the farmers.
Soil Water Depletion in Planted Alfalfa Pastures in an Alpine Pastoral Area
Authors: Sun Lei , Huang Ze , Cui Zeng , Lu Rong , Zhang Rui-Qi , Liu Yu , López-Vicente Manuel , Ahirwal Jitendra , Wei Xue-Hong , Wu Gao-Lin
Published: October 2018

Alfalfa (Medicago sativa) has strong stress resistance, high nutritional value, good palatability for cattle, high yield and a drought tolerance mechanism, but long-term planting leads to soil desiccation. This research was carried out to examine the soil water conditions of alfalfa pastures with different planted ages, and determine the optimum time for alfalfa rotation in a plateau area of a sub-alpine monsoon climate. Soil water depletion, soil compaction and vegetation characteristics of alfalfa pastures of different ages (i.e., two, four and seven years) were assayed and compared with those of a cornfield which served as the control crop. Three 20 × 20 m plots and five random quadrats per plot were established at each field. Soil water contents at 0–400 cm depth and plant biomass were compared among different vegetation types, soil transects and planting years. The results showed that at the 250–400 cm depth, the soil water storage of the four- and seven-year-old alfalfa pastures was much lower than in the two-year-old alfalfa pasture and in the cornfield. Moreover, the degree of soil water storage deficit of the four- and seven-year-old alfalfa pastures was much higher than in the other fields. Soil compaction of alfalfa pastures increased with increasing planting age and reached a peak value in the seven-year-old alfalfa pasture. The highest above-ground biomass was observed in the four-year-old alpine alfalfa pasture. Thus, the best cultivation period for alfalfa pastures was four years from the perspective of higher yield and lower soil water consumption in pastoral sub-alpine areas. This study provided a basis for sustainable alfalfa pasture cultivation, timely harvest, rotation and water management measures to be implemented in alpine grazing lands.
Comparative biological effects of spherical noble metal nanoparticles (Rh, Pd, Ag, Pt, Au) with 4–8 nm diameter
Authors: Rostek Alexander , Breisch Marina , Pappert Kevin , Loza Kateryna , Heggen Marc , Köller Manfred , Sengstock Christina , Epple Matthias
Published: October 2018

For a comparative cytotoxicity study, nanoparticles of the noble metals Rh, Pd, Ag, Pt, and Au (spherical, average diameter 4 to 8 nm) were prepared by reduction in water and colloidally stabilized with poly(N-vinyl pyrrolidone) (PVP). Thus, their shape, size, and surface functionalization were all the same. Size and morphology of the nanoparticles were determined by dynamic light scattering (DLS), analytical disc centrifugation (differential centrifugal sedimentation, DCS), and high-resolution transmission electron microscopy (HRTEM). Cell-biological experiments were performed to determine the effect of particle exposure on the viability of human mesenchymal stem cells (hMSCs). Except for silver, no adverse effect of any of the metal nanoparticles was observed for concentrations up to 50 ppm (50 mg L−1) incubated for 24 h, indicating that noble metal nanoparticles (rhodium, palladium, platinum, gold) that do not release ions are not cytotoxic under these conditions.
Unprecedented nucleophile-promoted 1,7-S or Se shift reactions under Pummerer reaction conditions of 4-alkenyl-3-sulfinylmethylpyrroles
Authors: Go Takashi , Morimatsu Akane , Wasada Hiroaki , Tanabe Genzoh , Muraoka Osamu , Sawada Yoshiharu , Yoshimatsu Mitsuhiro
Published: October 2018

A unique 1,7-S- and Se-shift reaction under Pummerer reaction conditions of 4-alkenyl-3-sulfinyl- and seleninylpyrroles was described. The usual Pummerer reaction of 4-(alkenylaminomethyl)-3-phenylsulfinylpyrroles and a successive reaction with tetrabutylammonium hydroxide (TBAH) yielded either pyrrolo[3,2-c]azepines or N-pyrrol-3-ylmethyl-N-(4-hydroxy-3-sulfanylpropyl)-p-toluenesulfonamides (diols). Seleno-Pummerer reactions of 3-selanylmethylpyrroles also proceeded via in situ generation of selenoxides, followed by a treatment with TBAH.
THE ANALYSIS OF ELEMENTS GEOMETRY POSITION IN THE IRANIAN GARDEN STRUCTURE
Authors: Mohammadi Hanieh , Valibeig Nima
Published: October 2018

Iranian garden has been known as a specific architecture in the whole world. Among all its special features, the geometrical structure of Iranian garden has always attracted the attention of architects and researchers. Nowadays, despite numerous studies on the Iranian gardens, the lack of geometrical studies and the extension of some old concepts have led to recognize the Iranian gardens based on a unique pattern in terms of geometry. This pattern has been known as an archetype and typifies the Iranian Garden Geometry as a quarter pattern. That it could not be a true hypothesis, because the impact of garden components on its structure has been neglected. Investigating geometric position of garden elements and their relationship with the general form of garden would provide more accurate theoretical basis for Iranian garden design. In addition, this approach could help experts to retrieve the ruined part of historical gardens. So far, extensive garden studies have been carried out more on the symbolic concepts, components introduction and typology according to times and locations. This article is the first attempt to study each common element’s geometry to realize how the spatial structures could be effective in the garden formation. This paper aims to recognize the architectural geometric logic of gardens based on library studies and field recordings.
TOWARDS ECO-NEIGHBORHOODS, SOLUTIONS FOR SUSTAINABLE DEVELOPMENT, CONSTRUCTION AND ENERGY SAVING TECHNOLOGIES
Authors: Omar Osama
Published: October 2018

Global interest in the concept of sustainability has prompted the swift and extensive developments of green technologies, products, competitions, organizations, and resources. As evidenced by international environmental agreements and conferences held that aim to resolve global warming such as the 2009 UN Climate Change Conference in Copenhagen, the world is becoming focused on sustainable policies and practices (Tibi, Ghaddar, & Ghali, 2012). This research will address the urban problems in present in Arab countries including environmental pollution and the evident social problems like disintegration and isolation by studying the three zones of Mar Mikhael, Arab el-Maslakh, and Nour Hajin which are known to be economically unequal. The methodology of this research is based on the analytical study of the three interdependent components of sustainable development and design which are society/people, the environment, and economics applying on each case study. This paper will identify solutions relative to environmental, technological, energy saving, as well as sustainable and green buildings in urban design. Some of the remaining solutions target solving environmental pollution and social problems. Others target to improve the quality of the economic level of the neighborhood. The result of this research will a number of recommendations on several levels (Governmental level, Local NGOs). Another type of results will be as architectural design solution for environmental issue and urban problems based on data collection of case study at several items by team of students attending in local competition of urban design.
It’s Complicated: A Big Data Approach to Exploring Planetesimal Evolution in the Presence of Jovian Planets
Authors: Grazier Kevin R. , Castillo-Rogez Julie C. , Horner Jonathan
Published: October 2018

Previous studies have suggested that the scattered disk is populated by planetesimals that once orbited in the reservoirs between the Jovian planets. Other studies have concluded that the source region for the Centaurs and Jupiter family comets (JFCs) is the scattered disk. Still other studies have suggested dynamical links between Centaurs and JFCs. The overarching goal of this study is to build upon our previous work and, using data mining techniques derived from big data applications, explore a database of close planet/planetesimal approaches in order to both examine these claims and demonstrate how complicated the trajectories of planetesimals wending between the Jovian planets can be—as they are subjected to impulsive alterations by close planetary encounters and resonant effects. Our results show that Centaurs, JFCs, and scattered disk objects are not dynamically distinct populations, and the paths planetesimals take over their lifetimes can be extremely complex. An understanding of this complexity offers solutions to other outstanding questions about the current solar system architecture.
A New Perspective on the Large-scale Tidal Effect on the Galaxy Luminosity and Morphology
Authors: Lee Jounghun
Published: October 2018

We study the mean tidal coherence of galaxy environments as a function of intrinsic luminosity determined by the absolute r-band magnitude. The tidal coherence of a galaxy environment is estimated as the cosine of the angle between two minor eigenvectors of the tidal field smoothed at the scales of 2 and 30 h
−1 Mpc, respectively, centered on each of the local galaxies from the Sloan Digital Sky Data Release 10. Creating four luminosity-selected samples of the Sloan galaxies, we control them to have identical density distributions in order to nullify the dominant effect of the local density. The samples containing more luminous wall and field galaxies were found to yield lower mean values of the tidal coherence, which is a trend that turns out to be robust against the variation of the smoothing scales. At a fixed morphology, the same trend is found for the late-type spiral and lenticular galaxies in both of the field and wall environments. The early-type spiral field galaxies show no significant dependence on the tidal coherence, while both of the least and most luminous elliptical wall galaxies are found to dwell in the regions with highest tidal coherence.
No Low-frequency Emission from Extremely Bright Fast Radio Bursts
Authors: Sokolowski M. , Bhat N. D. R. , Macquart J.-P. , Shannon R. M. , Bannister K. W. , Ekers R. D. , Scott D. R. , Beardsley A. P. , Crosse B. , Emrich D. , Franzen T. M. O. , Gaensler B. M. , Horsley L. , Johnston-Hollitt M. , Kaplan D. L. , Kenney D. , Morales M. F. , Pallot D. , Sleap G. , Steele K. , Tingay S. J. , Trott C. M. , Walker M. , Wayth R. B. , Williams A. , Wu C.
Published: October 2018

We present the results of a coordinated campaign conducted with the Murchison Widefield Array (MWA) to shadow fast radio bursts (FRBs) detected by the Australian Square Kilometre Array Pathfinder (ASKAP) at 1.4 GHz, which resulted in simultaneous MWA observations of seven ASKAP FRBs. We de-dispersed the 24 × 1.28 MHz MWA images across the 170–200 MHz band taken at 0.5 s time resolution at the known dispersion measures (DMs) and arrival times of the bursts and searched both within the ASKAP error regions (typically ∼10′ × 10′), and beyond (4° × 4°). We identified no candidates exceeding a 5σ threshold at these DMs in the dynamic spectra. These limits are inconsistent with the mean fluence scaling of α = −1.8 ± 0.3 (

, where ν is the observing frequency) that is reported for ASKAP events, most notably for the three high-fluence (

Jy ms) FRBs 171020, 180110, and 180324. Our limits show that pulse broadening alone cannot explain our non-detections, and that there must be a spectral turnover at frequencies above 200 MHz. We discuss and constrain parameters of three remaining plausible spectral break mechanisms: free–free absorption, intrinsic spectral turnover of the radiative processes, and magnification of signals at ASKAP frequencies by caustics or scintillation. If free–free absorption were the cause of the spectral turnover, we constrain the thickness of the absorbing medium in terms of the electron temperature, T, to <0.03 (T/104 K)−1.35 pc for FRB 171020.
A Search for the Host Galaxy of FRB 171020
Authors: Mahony Elizabeth K. , Ekers Ron D. , Macquart Jean-Pierre , Sadler Elaine M. , Bannister Keith W. , Bhandari Shivani , Flynn Chris , Koribalski Bärbel S. , Prochaska J. Xavier , Ryder Stuart D. , Shannon Ryan M. , Tejos Nicolas , Whiting Matthew T. , Wong O. I.
Published: October 2018

We report on a search for the host galaxy of FRB 171020, the fast radio burst (FRB) with the smallest recorded dispersion measure (DM; DM = 114 pc cm−3) of our ongoing ASKAP survey. The low DM confines the burst location within a sufficiently small volume to rigorously constrain the identity of the host galaxy. We identify 16 candidate galaxies in the search volume and single out ESO 601–G036, an Sc galaxy at redshift z = 0.00867, as the most likely host galaxy. Ultraviolet and optical imaging and spectroscopy reveal that this galaxy has a star formation rate of approximately 0.1 M
⊙ yr−1 and oxygen abundance 12 + log(O/H) = 8.3 ± 0.2, properties that are remarkably consistent with the galaxy hosting the repeating FRB 121102. However, in contrast to FRB 121102, follow-up radio observations of ESO 601–G036 show no compact radio emission above a 5σ limit of L
2.1GHz = 3.6 × 1019 W Hz−1. Using radio continuum observations of the field, combined with archival optical imaging data, we find no analog to the persistent radio source associated with FRB 121102 within the localization region of FRB 171020 out to z = 0.06. These results suggest that FRBs are not necessarily associated with a luminous and compact radio continuum source.
A synopsis of Estonian myriapod fauna (Myriapoda: Chilopoda, Diplopoda, Symphyla and Pauropoda)
Authors: Sammet Kaarel , Ivask Mari , Kurina Olavi
Published: October 2018

The data on Estonian Myriapoda are scattered in various publications and there has been no overview of the fauna up to the present. A critical summary of the previous information on Estonian Myriapoda is given, supplemented by new records and distribution maps. Altogether, 5784 specimens from 276 collecting sites were studied. To the hitherto recorded 14 centipede species are addedLithobiusmelanops,L.microps,Geophiluscarpophagus,G.flavus,StrigamiatranssilvanicaandStenotaenialinearis, a probably introduced species. Of the 27 published Estonian millipede species, the data on two species proved erroneous, and two new species were recorded (CraspedosomaraulinsiiandCylindroiulusbritannicus). Two previously recorded millipede species –BrachyiuluspusillusandMastigophorophyllonsaxonicum– were not found in the recent samples, the latter may have become more rare or extinct. Pauropoda and Symphyla lack previous reliable records. Combined with published data, the number of myriapod species known from Estonia is now set at 52. Some changes in species distribution and frequencies were detected comparing the published data with new records. Some data about habitat preferences of the more common species are also given. The majority of species have a western Palaearctic distribution, while six species are at the northern limit of their ranges.
The first record of the anopsobiid genus Shikokuobius Shinohara, 1982 in continental Asia, with the description of a new species from the Altais, southwestern Siberia, Russia (Chilopoda, Lithobiomorpha, Anopsobiidae)
Authors: Farzalieva Gyulli Sh. , Nefediev Pavel S.
Published: October 2018

A new lithobiomorph species, Shikokuobiusaltaicussp. n., is described from the Altai Mountains in southwestern Siberia, Russia. This is the first record of the genus Shikokuobius Shinohara, 1982 in continental Asia, all previous reports being from Japan. The distribution of Shikokuobius is mapped.
The ‘danmu’ phenomenon and media participation: Intercultural understanding and language learning through ‘The Ministry of Time’
Authors: Zhang Leticia-Tian , Cassany Daniel
Published: October 2018

While research on Western multimedia platforms, such as YouTube, is prolific and interdisciplinary, Asian portals remain unknown. We explore this field by analyzing the juvenile and intercultural uses of a popular visualization system in Japan and China, known as “danmaku” or “danmu”. This technology inserts dynamic and contextualized comments on a photogram, with several typographical possibilities. Based on a corpus of 1,590 comments on “The Ministry of Time,” collected from a fandom platform with millions of users, we analyzed the topics that arouse the most interest among Chinese fans. We combine content analysis, which incorporates coding and counting techniques of the categories with the most interventions (n>16), with multimodal discourse analysis (TV series, Asian platform and user comments). Results show that the viewers are most interested in the film genre (time travel), the characters, the plot, certain sociocultural contents, and the Spanish language. Their discussions address issues of interculturality, some topics that are taboo in China and the fandom culture in Asia. Our study illustrates the potential of participation, communication, and learning in Asian social media, and constitutes an interesting and innovative contribution to the field of media and digital literacy, with various suggestions to promote intercultural competence with the use of popular culture.

Mientras la investigación sobre las plataformas multimedia occidentales, como YouTube, es prolífica e interdisciplinaria, los portales asiáticos siguen siendo desconocidos. El presente trabajo explora este campo analizando los usos juveniles e interculturales de un sistema de visualización popular en Japón y China, conocido como «danmaku» o «danmu». Esta tecnología inserta comentarios dinámicos y contextualizados sobre un fotograma, con varias posibilidades tipográficas. Partiendo de un corpus de 1.590 comentarios sobre «El Ministerio del Tiempo», recogidos de una plataforma de «fandom» con millones de seguidores, este artículo analiza los temas que despiertan más interés entre los fans chinos. El análisis de contenido, que incorpora técnicas de «coding and counting» de las categorías con más intervenciones (n>16), se combina con un análisis del discurso multimodal (serie de TV, plataforma asiática y comentarios de usuarios). Los resultados muestran que los espectadores se interesan por el género cinematográfico (viaje del tiempo), los personajes, la trama, determinados contenidos socioculturales y la lengua española. Sus discusiones abordan cuestiones de interculturalidad, algunas cuestiones que son tabú en China y la cultura «fandom» en Asia. El estudio ilustra las potencialidades de participación, comunicación y aprendizaje en las redes sociales asiáticas, y supone una aportación interesante e innovadora al campo de la alfabetización mediática y digital, con varias sugerencias para fomentar la competencia intercultural con el uso de la cultura popular.
Young people learning from digital media outside of school: The informal meets the formal
Authors: Pereira Sara , Fillol Joana , Moura Pedro
Published: October 2018

The dissonance between what teenagers learn in classrooms and their everyday lives is not a recent phenomenon, but it is increasingly relevant as school systems are unable to follow the evolution of media and society beyond traditional concerns regarding the protection of young people. An overly scholarly view of learning continues to prevail in our society, which seems to marginalize the knowledge that young people develop with and through media and digital platforms. Based on questionnaires, workshops, and interviews conducted with Portuguese teenagers, aged 12 to 16 years old (N=78), attending an urban and a rural school in the North of the country, this paper aims to understand how these teens are learning to use the media, what motivates them, and if their media practices contribute to the acquisition of skills and competencies useful to their lives inside and outside school. The research main results confirm the existence of a gap between formal and informal education. Informal education is mainly motivated by their needs and peer influence. Colleagues and family, alongside the Internet and self-discovery, appear as important sources of knowledge. Another important conclusion is that informal learning strategies contribute to the development of skills and competencies that are useful from a school viewpoint.

La disonancia entre lo que aprenden los jóvenes en clase y en su vida cotidiana no es un fenómeno reciente, pero es cada vez más relevante, ya que la escuela no es capaz, evidentemente, de acompañar la evolución. En nuestra sociedad, sigue prevaleciendo una visión demasiado escolarizada del aprendizaje, que parece marginalizar los conocimientos que los jóvenes desarrollan con y a través de los medios y de las plataformas digitales. Basado en cuestionarios, entrevistas y talleres realizados con jóvenes portugueses entre los 12 y los 16 años (N=78), de una escuela urbana y otra rural del norte del país, este artículo pretende comprender cómo están estos jóvenes aprendiendo a usar los medios, lo que les motiva y si lo que hacen con ellos contribuye a la adquisición de capacidades y competencias útiles para sus vidas dentro y fuera de la escuela. Los principales resultados de la investigación confirman la existencia de un foso entre la educación formal e informal. La educación informal es sobretodo motivada por sus necesidades y por la influencia de sus pares. Los compañeros y la familia, junto con Internet y con lo que descubren por ellos mismos, aparecen como importantes fuentes de conocimiento. También se concluyó que las estrategias informales de aprendizaje contribuyen al desarrollo de capacidades y competencias útiles desde un punto de vista escolar.
Conflicts in the professional roles of journalists in Spain: Ideals and practice
Authors: Roses-Campos Sergio , Humanes-Humanes María-Luisa
Published: October 2018

Based on a survey of 122 journalists from four Spanish newspapers carried out from 2015 to 2016, this paper analyses to what extent these professionals perceive a disconnection –a gap– between their role conception and their perceived role enactment, that is between their professional ideals and their journalistic practice, and which are the most “conflicting” roles in a Polarized Pluralist media system. According to the perceptions of the professionals surveyed, journalists in Spain hold a role conflict when they work in a newspaper. The findings show significant differences between the role conception and the perceived role enactment in six of the seven professional roles. The biggest divergences are located in the watchdog, civic and disseminator roles. The conflict between the professional ideals and their implementation in the news is always resolved in favor of the media organizations. Our results are consistent and support the previous studies that have defined the Polarized Pluralist media system as a media ecosystem where journalists accumulate little power compared to the media organizations, which are in financial debt and dependent on political and economic powers. Results are discussed according to the literature review as well as the context in which the study was developed.

A partir de una encuesta realizada entre 2015 y 2016 a 122 periodistas de cuatro diarios españoles, el artículo estudia en qué medida estos profesionales perciben una desconexión –una brecha– entre sus ideales y su puesta en práctica, y cuáles son los roles más «conflictivos» en el contexto de un sistema de medios de pluralismo polarizado. Los resultados indican, a tenor de la percepción de los profesionales encuestados, que los periodistas presentan un conflicto de roles ya que se hallaron diferencias significativas entre la concepción de seis de los siete roles profesionales y la percepción de la puesta en práctica de dichas funciones. Las mayores divergencias se localizan en los roles vigilante, cívico y diseminador. Los conflictos de roles se resolvieron en todos los casos a favor de los intereses de quienes detentan el poder y en contra de los ideales de los periodistas. Estos resultados son congruentes y apoyan los hallazgos de publicaciones previas que retratan al sistema de medios de pluralismo polarizado como un ecosistema mediático donde los profesionales del periodismo, como colectivo, acumulan poco poder frente al ostentado por las organizaciones de medios, endeudadas por una excesiva «financierización» y dependientes del poder político y económico. Los resultados se discuten de acuerdo con la literatura existente, así como con el contexto en que se realizó la investigación.
Google or Gutenberg Generation: Chilean university students’ reading habits and reading purposes
Authors: Parodi Giovanni , Moreno-de-León Tomás , Julio Cristóbal , Burdiles Gina
Published: October 2018

It has always been in the public interest to know the reading habits of readers of various ages and levels of schooling, as well as their opinions with regard to the consumption of reading materials. Lately, researchers have given increased attention to digital texts. Although progress on these topics has been made as reported in published research, there is yet incomplete information regarding readers’ habits and opinions at university and professional levels. This study describes the self-reported habits of university students belonging to two disciplinary domains (Human Sciences and Economic and Business Sciences) regarding reading on paper or on digital media for three purposes: academic, entertainment, and information seeking. The results reveal that the readers’ preferences vary according to the three purposes. These readers reported using different media but had a clear preference for paper; they also reported distinguishing between cognitive processes (memory, comprehension, and learning), with the discipline to which they belonged having no radical effect on their preferences. All of this leads us to conclude that currently there exists a generation in transition, a ‘Gutenberg-Google’ generation, which still recognizes the relevance of paper, in particular for academic purposes.

Conocer los hábitos de lectura de sujetos de diversas edades y niveles de escolarización, así como su opinión respecto del consumo de materiales de lectura, ha estado siempre en el interés público. En los últimos tiempos, mayor énfasis se ha puesto en los textos digitales. Si bien se ha avanzado en la investigación en estas áreas, aun es parcial la información a nivel universitario y profesional. En este estudio se describen los hábitos declarados por estudiantes universitarios de dos áreas disciplinares (ciencias humanas y ciencias económicas y administrativas) respecto de lectura en formato papel y en digital en virtud de tres propósitos: académico, entretenimiento y búsqueda de información. Para ello, se diseñó y aplicó una encuesta a una muestra de 894 estudiantes en dos universidades chilenas y en cinco carreras. Los resultados revelan que los lectores muestran variación en sus preferencias de lectura según los tres propósitos. En otras palabras, estos lectores declaran emplear soportes diferentes, pero con una clara tendencia a preferir mayoritariamente el sustrato papel, y distinguir procesos cognitivos diversos (memoria, comprensión y aprendizaje), sin que el área disciplinar de procedencia incida de modo radical en sus preferencias. Todo ello, en general, nos lleva a concluir que en la actualidad existe una generación en transición «Gutenberg-Google», la cual aún reconoce y otorga alta relevancia al soporte papel, en particular frente a propósitos académicos.
Profits and purpose: Organizational tensions in social enterprises
Authors: Vazquez-Maguirre Mario , Portales Luis
Published: October 2018

Purpose: This paper aims to explore the way in which three indigenous social enterprises from Guatemala, Mexico and Peru, solve the paradox of simultaneously producing social and economic value, which creates organizational tensions.Design/methodology/approach: This research follows a qualitative method based on a case study research strategy. Three different data collection techniques are applied: Analysis of internal reports, direct observation, and semi-structured interviews with relevant stakeholder, mainly employees and managers.Findings: Indigenous social enterprises deal with organizational tensions by adopting different organizational structures and privileging one dimension over the other (social or economic) in decision making Social implications. Indigenous social enterprises generate quality of life and reduce historical exclusion patterns by strengthening local economy dynamics through social innovation.Originality/value: Social innovations, appreciated in different organizational structures, contribute to alleviate the tension that arises from managing entities with double purpose. Also, this research provides evidence of how marginalized groups can overcome exclusion and poverty conditions by creating indigenous social enterprises.
Lateral Rectus–Medial Rectus Union: A New Surgical Technique for Treatment of Complete Third Nerve Palsy
Authors: Bagheri Abbas , Feizi Mohadeseh , Sahebghalam Ramin , Yazdani Shahin
Published: October 2018

Purpose:

To describe a new surgical technique for the treatment of complete third nerve palsy.

Methods:

This study included patients with chronic complete third nerve palsy. The lateral rectus muscle was split, followed by disinsertion of the superior and inferior halves, which were passed between the sclera and superior and inferior rectus muscles, respectively. Then the medial rectus muscle was sutured as posteriorly as possible from its insertion and cut. Next, the distal stump of the medial rectus muscle was split into two halves and united with the superior and inferior halves of the lateral rectus muscle. Finally, the proximal portion of the medial rectus muscle was sutured back to its original insertion. In cases with hypotropia and a functional superior oblique muscle, superior oblique tenectomy was also performed. Success was defined as postoperative horizontal deviation of 10 prism diopters (PD) or less and vertical deviation of 5 PD or less.

Results:

Ten patients with a mean age of 32.4 ± 18.4 years had surgery using this technique; 2 of them had a history of strabismus surgery. Mean exotropia was 84 ± 14.9 PD, which reduced to 6.5 ± 8.2 PD. Mean vertical deviation was 16.5 ± 10 PD, which reduced to 2.5 ± 3.5 PD. Mean follow-up was 13.2 ± 7.9 months, and the success rate was 70% and 90% for horizontal and vertical deviations, respectively.

Conclusions:

The lateral rectus–medial rectus union technique is an effective and long-lasting procedure to overcome large-angle exotropia associated with complete third nerve palsy. This method can also be employed as a reoperation procedure.

[

J Pediatr Ophthalmol Strabismus
. 2019;56(1):10–18.]
Comparison of Optic Canal Diameter in Children With Malignant Infantile Osteopetrosis and Normal Children and the Effects of Hematopoietic Stem Cell Transplantation on the Optic Canal Diameter
Authors: Cao Wenhong , Wei Wenbin , Yu Gang , Wu Qian , Qin Maoquan
Published: October 2018

Purpose:

To investigate the difference in the optic canal diameter between children with autosomal recessive malignant infantile osteopetrosis and normal children, and to assess the influence of hematopoietic stem cell transplantation on the optic canal diameter.

Methods:

Twenty pediatric patients with malignant infantile osteopetrosis and 22 normal control children were included in this study. Eleven patients with malignant infantile osteopetrosis underwent hematopoietic stem cell transplantation. The measurements included optical canal diameter and flash visual evoked potential. Comparisons of these measurements between patients with malignant infantile osteopetrosis and normal controls as well as before and after hematopoietic stem cell transplantation were performed. The correlation between age and optic canal diameter was analyzed using Pearson correlation analysis.

Results:

The mean optic canal diameter before hematopoietic stem cell transplantation was 1.65 ± 0.54 mm in patients with malignant infantile osteopetrosis and 3.38 ± 0.60 mm in the control group (
P
< .001). The mean optic canal diameter after hematopoietic stem cell transplantation was 2.72 ± 0.66 mm, which was significantly different from the pre-transplantation measurement (
P
< .001). The P2 latency for the flash visual evoked potential after hematopoietic stem cell transplantation (152.3 ± 36.4 ms) was significantly less than that before transplantation (165.5 ± 27.7 ms;
P
= .051). Pearson correlation analysis revealed a significant correlation between age and optic canal diameter (
r
= 0.722,
P
< .001).

Conclusions:

The optic canal was narrower in pediatric patients with malignant infantile osteopetrosis than in age-matched normal controls. This condition can be relieved through hematopoietic stem cell transplantation and the impaired conductibility of the optic nerve can be improved in some cases.

[
J Pediatr Ophthalmol Strabismus.
2019;56(1):35–42.]
Efficacy of Office-Based Nasolacrimal Duct Probing
Authors: Bach Austin , Vanner Elizabeth Ann , Warman Roberto
Published: October 2018

Purpose:

To analyze the efficacy of nasolacrimal duct probing conducted in the office for nasolacrimal duct obstruction.

Methods:

A retrospective chart review was conducted of 1,294 patients. Of those, 1,227 patients who underwent office-based nasolacrimal probings of the nasolacrimal duct at a single tertiary care center were included.

Results:

A total of 82 (6.7%) patients needed reprobing. Of the 82 patients who underwent a second procedure, 35 (43%) underwent a second in-office probing with a success rate of 77%. The 8 (22%) patients who failed the second in-office probing underwent probing and Crawford stent placement in the operating room and their symptoms resolved. For the 47 (57%) patients who failed the primary in-office probing and underwent operating room probing and stent placement, only 1 (2%) needed a second operating room probing and stent placement. Logistic regression analyses indicated an increased likelihood of needing a secondary procedure with increased age at the time of the first probing.

Conclusions:

This large, retrospective analysis of office-based probings demonstrated a success rate of 93.3% with increased likelihood of not needing a second procedure with probing at a younger age. This study demonstrates an excellent success rate for in-office probings for patients both younger and older than 12 months. This not only shows a high rate of efficacy, but is also highly cost efficient when compared to primary probing in the operating room.

[
J Pediatr Ophthalmol Strabismus
. 2019;56(1):50–54.]
Surgical Outcome of Single Inferior Oblique Myectomy in Small and Large Hypertropia of Unilateral Superior Oblique Palsy
Authors: Akbari Mohammad Reza , Sadrkhanlou Samira , Mirmohammadsadeghi Arash
Published: October 2018

Purpose:

To determine the efficacy of isolated inferior oblique myectomy on hypertropia in primary position, side gazes, and tilts, and its effect on comitancy and abnormal head posture in unilateral superior oblique palsy.

Methods:

Thirty-nine patients with unilateral superior oblique palsy who had inferior oblique overaction underwent inferior oblique myectomy. The hypertropia was measured in primary position, side gazes, and tilts preoperatively and postoperatively. Abnormal head posture was also assessed. Success was defined as primary position hypertropia of 5 prism diopters (PD) or less.

Results:

The mean distance hypertropia was 15.7 ± 7.7 PD (range: 3 to 30 PD) preoperatively and 1.5 ± 3.3 PD (range: 0 to 16 PD) postoperatively (
P
< .001). The mean reduction of distance hypertropia postoperatively was 14.2 ± 7.8 PD (range: 3 to 30 PD). The contralateral gaze hypertropia decreased from 21.7 ± 9.0 PD (range: 5 to 45 PD) preoperatively to 3.6 ± 5.1 PD postoperatively (range: 0 to 20 PD) and ipsilateral head tilt hypertropia decreased from 21.9 ± 8.4 PD (range: 8 to 40 PD) preoperatively to 5.0 ± 5.9 PD (range: 0 to 24 PD) postoperatively (
P
< .000 for both). Incomitance (contralateralipsilateral gaze hypertropia) decreased from 15.0 ± 7.4 PD (range: 3 to 35 PD) preoperatively to 2.8 ± 4.1 PD (range: 0 to 16 PD) postoperatively (
P
< .001). The success rate between the two groups of patients who had hypertropia of 15 PD or less and greater than 15 PD in primary position was not statistically different (94.7% vs 85%). Two patients underwent a second operation for residual hypertropia. There was no overcorrection. Thirty-two patients had abnormal head posture, which resolved postoperatively in 29 cases.

Conclusions:

Isolated inferior oblique myectomy is an effective procedure in resolving hypertropia up to 30 PD due to unilateral superior oblique palsy, with a minimal risk of overcorrection and low risk of undercorrection. It decreases incomitancy, is a self-titrating procedure, and resolves abnormal head posture efficiently.

[
J Pediatr Ophthalmol Strabismus
. 2019;56(1):23–27.]
Analysis of Macular Vessel Density and Foveal Avascular Zone Using Spectral-Domain Optical Coherence Tomography Angiography in Children With Amblyopia
Authors: Demirayak Bengi , Vural Asli , Onur Ismail Umut , Kaya Fatma Selin , Yigit Fadime Ulviye
Published: October 2018

Purpose:

To quantify the foveal avascular zone and the whole, parafoveal, and foveal vessel density of superficial and deep capillary plexus in amblyopic eyes and age-matched controls and to compare the measurements.

Methods:

This cross-sectional study involved 49 eyes from 17 patients with amblyopia and 21 healthy children (aged 6 to 16 years). Optical coherence tomography angiography was performed for all participants and superficial capillary plexus, deep capillary plexus, and foveal avascular zone were evaluated. Data from amblyopic eyes, fellow eyes with unilateral amblyopia, and control eyes were compared using the Mann–Whitney
U
test.

Results:

The mean patient age was 8.6 ± 2.5 years in the amblyopia group and 9.6 ± 2.9 years in the control group. The mean foveal avascular zone measurements were 0.251 ± 0.1 mm
2
in the amblyopia group and 0.291 ± 0.1 mm
2
in the control group. The whole, foveal, and parafoveal vessel densities of superficial capillary plexus were 48.8% ± 3.7%, 23.8% ± 8.8%, and 50.9% ± 4.6% in the amblyopia group and 48.4% ± 2.5%, 19.3% ± 5.4%, and 51.3% ± 2.7% in the control group. The whole, foveal, and parafoveal vessel densities of deep capillary plexus were 51.8% ± 4.3%, 37.6% ± 5.8%, and 54.8% ± 4.2% in the amblyopia group and 54.4% ± 3.2%, 34.9% ± 7.4%, and 56.8% ± 3.2% in the control group. No statistically significant difference was detected in all measurements.

Conclusions:

Assessment of the foveal avascular zone and vessel density of superficial capillary plexus and deep capillary plexus with optical coherence tomography angiography revealed no difference between amblyopic eyes, controls, and fellow eyes of patients with unilateral amblyopia.

[
J Pediatr Ophthalmol Strabismus
. 2019;56(1):55–59.]
Quantitative Descriptors of Corneal Shape Derived from Computer-assisted Analysis of Photokeratographs
Authors: Dingeldein Steven A , Klyce Stephen D , Wilson Steven E
Published: October 2018

ABSTRACT: The goal of this retrospective study was to derive clinically useful quantitative measures of corneal shape from computer-assisted analyses of photokeratoscope photographs. Algorithms were developed to determine a new index of corneal symmetry, the Surface Asymmetry Index (SAI). The SAI correlated well with best spectacle-corrected visual acuity and may be useful clinically for predicting the level of spectacle-corrected visual acuity that could be expected based on the corneal surface topography in the otherwise normal eye of an individual patient. Algorithms were also developed to determine the centrally-weighted average corneal power and the power and location of the steepest and flattest corneal meridians. The average surface power and the power of the steepest meridian determined from the photokeratographs correlated well with values obtained using the keratometer in the retrospective series (correlation coefficient = 0.98 for the average surface power and 0.97 for the power of the steepest meridian). [Refractive and Corneal Surgery 1989; 6:372-378.]
Descemet's Stripping With Endothelial Keratoplasty in 50 Eyes: A Refractive Neutral Corneal Transplant
Authors: Price Francis W , Price Marianne O
Published: October 2018

ABSTRACT

PURPOSE: To evaluate early visual and refractive outcomes following treatment of corneal endothelial dysfunction with a corneal transplantation technique, Descemet's stripping with endothelial keratoplasty (DSEK).

METHODS: Visual and refractive outcomes of the first 50 consecutive cases of DSEK performed by a single surgeon between December 2003 and July 2004 were analyzed retrospectively. The DSEK technique consisted of stripping Descemet's membrane and endothelium from a recipient cornea and transplanting the posterior stroma and endothelium of a donor cornea through a 5-mm incision.

RESULTS: Results are reported for 50 eyes in 47 patients (30 women and 17 men). Mean patient age at surgery was 70±12 years (range: 34 to 89 years). Five eyes were treated for corneal edema or bullous keratopathy and 45 for Fuchs' endothelial dystrophy. Seven eyes were phakic and 43 were Pseudophakic. Six months after surgery, mean manifest cylinder was 1.5±0.94 diopters (D), unchanged from preoperative cylinder of 1.5±1.0 D. Mean manifest spherical equivalent refraction was 0.15 ±1.5 D at 6-month follow-up compared with -0.36±1.4 D preoperatively (P=.10) At 3- and 6-month follow-up, significant improvement was noted in mean best spectacle-corrected visual acuity compared with the preoperative mean of 20/100 (P=.007). At 6-month follow-up, 31 (62%) eyes refracted to ≥20/40 and 38 (76%) eyes saw ≥20/50.

CONCLUSIONS: Compared to standard penetrating keratoplasty, DSEK causes minimal refractive change and provides rapid visual recovery for patients with endothelial dysfunction. This technique maintains the structural integrity of the cornea by preserving the recipient's epithelium, Bowman's layer, and entire stromal thickness. [J Refract Surg. 2005;21:339-345.]
Primera cita en Sudamérica de tres especies alóctonas de áfidos (Hemiptera, Aphididae) recogidos en la Argentina
Authors: Ortego J. , Mier Durante M. P. , Nieto Nafría J. M.
Published: October 2018

Se citan por primera vez en Sudamérica tres especies de áfidos (Hemiptera, Aphididae) a partir de colectas realizadas en las provincias argentinas de Mendoza, Río Negro y San Luis: Uroleucon taraxaci (Kaltenbach, 1843) relacionada con la adventicia Taraxacum officinale, y Siphonatrophia cupressi Swain, 1918 y Liosomaphis berberidis (Kaltenbach, 1843) que pueden afectar a plantas de jardinería. Se aportan datos morfológicos que las caracterizan y otros sobre su biología y distribución, que facilitarán el seguimiento de su posible dispersión en América del Sur.