bluuebunny/crossref_metadata_2025_split huggingface dataset:
realidad virtual y el Diseño Universal de Aprendizaje
Authors: Romero-Esquinas María Helena , Hidalgo-Ariza María Dolores , Muñoz-González Juan Manuel , Ariza-Carrasco Cristian 
Published: June 2024

This paper is based on an educational experience carried out in a faculty of education in Andalusia, in which, through some class dynamics, students worked with virtual reality and, specifically, with Pil Books as a digital tool. The methodology used in this research is quantitative and the instrument used is a questionnaire, developed ad hoc, with the aim of knowing what perception future teachers have of the use of Pil Books as well as its potential at the curricular level and for the development of skills and executive functions. This paper presents a descriptive analysis of the dimensions and items that make up the questionnaire, different analyses of variance (ANOVA), and multiple linear regressions to find out if any of the variables in this study predicts another. The results show that students make a positive assessment of the digital tool and that it has positive implications at the curricular level and in the development of students’ attention and decision-making abilities. In addition, we conclude that the students' perception of the tool is predicted by the applications it has for the class curriculum and by the way in which it allows the development of the students' executive functions and skills.
Este trabajo está basado en una experiencia educativa realizada en una facultad de educación de Andalucía, en la que, a través de una dinámica, los y las estudiantes trabajaron con realidad virtual y, en concreto, con Pil Books como herramienta digital. La metodología utilizada en esta investigación es de corte cuantitativo y el instrumento que se utiliza es un cuestionario, elaborado ad hoc, con el objetivo de conocer la percepción que tienen los futuros docentes acerca del uso de Pil Books así como sus potencialidades a nivel curricular y desarrollo de habilidades y funciones ejecutiva a través de esta herramienta. A lo largo de este trabajo se exponen un análisis descriptivo de las dimensiones y de los ítems que conforman el cuestionario; distintos análisis de varianza (ANOVA); así como regresiones lineales múltiples para conocer si alguna variable del estudio es predictora de otra. Los resultados muestran que el estudiantado hace una valoración positiva de la herramienta digital y que, tiene implicaciones positivas a nivel curricular y en el desarrollo de la atención y en la capacidad de toma de decisiones. Además, se concluye que la percepción del estudiantado sobre la herramienta es predicha por las aplicaciones que tiene a nivel curricular y por la forma en que permite desarrollar las funciones ejecutivas y habilidades de los y las estudiantes.
Mujeres de Caño Indio Tibú - sustitución de cultivos de uso ilícito y seguridad alimentaria.
Authors: Alba Maldonado José Manuel , Santiago Velásquez Javier Alonso , Jácome Garzón Edidvanidt 
Published: June 2024

Este artículo tiene como objetivo reconocer el papel de la mujer de Caño Indio Tibú en torno a la seguridad alimentaria en el marco del proceso de sustitución de cultivos de uso ilícito en el año 2017, utilizando como método el estudio de caso, entrevistas directas estructuradas y observación participante. En este sentido las familias de Caño Indio Tibú, viven una crisis alimentaria, debido a dos factores: uno, el incumplimiento por parte del Estado y dos, a la inexistencia de cultivos de pan coger en sus fincas. Así mismo, las mujeres de la vereda Caño Indio consideraron a partir de sus experiencias y de las actuales condiciones, que para llevar a cabo un proceso de sustitución de cultivos de uso ilícito en Colombia, es necesario garantizar en primera instancia procesos autónomos de seguridad alimentaria de las familias que acceden a estos proyectos de sustitución.
Palladium‐Catalyzed Allylic Alkylation of Doubly Deprotonated Carboxylic Acids
Authors: Braun Manfred , Meletis Panos , Visse Robin 
Published: December 2011

AbstractDoubly deprotonated carboxylic acids undergo smooth palladium‐catalyzed carbon alkylations with the allylic substrates methyl allyl carbonate and (E)‐methyl (pent‐3‐en‐2‐yl) carbonate to give γ,δ‐unsaturated carboxylic acids. A diastereoselective and enantioselective protocol leads to (2S,3R)‐hexenoic acid in 87% ee.
User‐Friendly [(Diglyme)NiBr2]‐Catalyzed Direct Alkylations of Heteroarenes with Unactivated Alkyl Halides through CH Bond Cleavages
Authors: Ackermann Lutz , Punji Benudhar , Song Weifeng 
Published: December 2011

AbstractA nitrogen and phosphorus ligand‐free catalytic system derived from inexpensive [(diglyme)NiBr2] allowed for efficient direct CH bond alkylations of heteroarenes with unactivated β‐hydrogen‐containing alkyl halides under basic reaction conditions.
Controlled Synthesis and Energy Applications of One‐Dimensional Conducting Polymer Nanostructures: An Overview
Authors: Yin Zhigang , Zheng Qingdong 
Published: December 2011

AbstractThe past decade has witnessed increasing attention in the synthesis, properties, and applications of one‐dimensional (1D) conducting polymer nanostructures. This overview first summarizes the synthetic strategies for various 1D nanostructures of conjugated polypyrrole (PPy), polyaniline (PANI), polythiophene (PTh), poly(p‐phenylenevinylene) (PPV) and derivatives thereof. By using template‐directed or template‐free methods, nanoscale rods, wires/fibers, belts/ribbons, tubes, arrays, or composites have been successfully synthesized. With their unique structures and advantageous characteristics (e.g., high conductivity, high carrier mobility, good electrochemical activity, large specific surface area, short and direct path for charge/ion transportation, good mechanical properties), 1D conducting polymer nanostructures are demonstrated to be very useful for energy applications. Next, their applications in solar cells, fuel cells, rechargeable lithium batteries, and electrochemical supercapacitors are highlighted, with a strong emphasis on recent literature examples. Finally, this review ends with a summary and some perspectives on the challenges and opportunities in this emerging area of research.
Active involvement of alarmins S100A8 and S100A9 in the regulation of synovial activation and joint destruction during mouse and human osteoarthritis
Authors: van Lent Peter L. E. M. , Blom Arjen B. , Schelbergen Rik F. P. , Slöetjes Annet , Lafeber Floris P. J. G. , Lems Willem F. , Cats Hans , Vogl Thomas , Roth Johannes , van den Berg Wim B. 
Published: December 2011

AbstractObjectiveTo investigate whether alarmins S100A8 and S100A9 are involved in mediating cartilage destruction during murine and human osteoarthritis (OA).MethodsTwo different murine models of OA that differed in terms of synovial activation were compared. Cartilage destruction was measured histologically. Synovial biopsy and serum samples from OA patients were derived from the Cohort Hip and Cohort Knee (CHECK) patients with symptomatic early OA. Expression of mediators in the synovium was measured by reverse transcription–polymerase chain reaction analysis and immunolocalization.ResultsIn collagenase‐induced OA, which showed marked synovial activation, interleukin‐1β was expressed at significant levels only during the early stages of disease, whereas S100A8 and S100A9 expression remained high for a prolonged period of time (up to day 21 after induction). In S100A9‐knockout mice, we found a major impact of S100A8 and S100A9 on synovial activation (62% inhibition) and OA cartilage destruction (45–73% inhibition) as compared to wild‐type controls. In contrast, in the surgically induced destabilized medial meniscus model, in which synovial involvement is scant, we found no role of S100A8 and S100A9 in the focal OA cartilage destruction. Examination of arthroscopic synovial biopsy samples from patients in the early symptomatic OA CHECK cohort revealed substantial levels of S100A8 and S100A9 messenger RNA and protein, which correlated significantly with synovial lining thickness, cellularity in the subintima, and joint destruction. Levels of S100A8/A9 serum protein were significantly enhanced (19%) at baseline in patients who had pronounced progression of joint destruction after 2 years.ConclusionOur data suggest that the S100A8 and S100A9 proteins are crucially involved in synovial activation and cartilage destruction during OA and that high levels may predict joint destruction in humans with OA.
Metal uptake by microalgae: Underlying mechanisms and practical applications
Authors: Monteiro Cristina M. , Castro Paula M. L. , Malcata F. Xavier 
Published: December 2011

AbstractMetal contamination of a few aquatic, atmospheric, and soil ecosystems has increased ever since the industrial revolution, owing to discharge of such elements via the effluents of some industrial facilities. Their presence to excessive levels in the environment will eventually lead to serious health problems in higher animals owing to accumulation throughout the food web. Current physicochemical methods available for recovery of metal pollutants (e.g., chemical precipitation, oxidation/reduction, or physical ion exchange) are either expensive or inefficient when they are present at very low concentrations. Consequently, removal of toxic metals by microorganisms has emerged as a potentially more economical alternative. Microalgae (in terms of both living and nonliving biomass) are an example of microorganisms suitable to recover metals and able to attain noteworthy percent removals. Their relatively high metal‐binding capacities arise from the intrinsic composition of their cell walls, which contain negatively charged functional groups. Consequently, microalgal cells are particularly efficient in uptake of those contaminants when at low levels. Self‐defense mechanisms developed by microalgal cells to survive in metal‐containing media and environmental factors that affect their removal (e.g., pH, temperature, and biomass concentration) are reviewed here in a comprehensive way and further discussed in attempts to rationalize this form of remediation vis‐a‐vis with conventional nonbiological alternatives. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Chemical Constituents of the Fermented Broth of the Ascomycete Theissenia cinerea 89091602
Authors: Liang Wen‐Li , Hsiao Che‐Jen , Ju Yu‐Ming , Lee Liang‐Hsin , Lee Tzong‐Huei 
Published: December 2011

AbstractOne new betaenone, theissenoic acid (1), together with three new acetogenins, theissenolactones A–C (2–4, resp.), were isolated from the fermented broth of Theissenia cinerea 89091602 isolated in Taiwan. The structures of 1–4 were elucidated by spectroscopic methods. Biological tests revealed that 3 and 4 exhibited moderate growth‐inhibitory activities against A549 lung cancer cell line with GI50 values of 14.9 and 47.9 μM, respectively.
Thiophene‐Containing Pechmann Dyes and Related Compounds: Synthesis, and Experimental and DFT Characterisation
Authors: Kantchev Eric Assen B. , Norsten Tyler B. , Tan Marilyn L. Y. , Ng Joey J. Y. , Sullivan Michael B. 
Published: December 2011

AbstractAttaching 2‐thienyl residues to the Pechmann dye core chromophore (5,5‐exo‐dilactone situated around a CC double bond) results in a novel magenta‐coloured compound (UV/Vis spectroscopy λmax=570 nm in CHCl3), which can be rearranged to a yellow 6,6‐endo‐dilactone (λmax=462 nm in CHCl3). Single and double amidation results in pronounced redshift in the 5,5‐exo series (violet, λmax=570 nm and blue, λmax=606 nm in CHCl3, respectively) but pronounced blueshift in the 6,6‐endo series (yellow, λmax=424 nm and pale yellow bordering on colourless, λmax=395 nm in CHCl3, respectively). Incorporation of a 3‐alkyl substituent on the thiophene ring allows for sharp increase of solubility in organic solvents concomitant with fine‐tuning of the colour: a redshift in 5,5‐exo‐dilactones but a blueshift in 5,5‐exo‐dilactams. DFT computations demonstrate that both lactone classes are planar regardless of the presence of a 3‐alkyl group. The lactam derivatives are non‐planar: the thiophene‐core chromophore dihedral angles increase on going from 5,5‐exo to 6,6‐endo and from thiophene to 3‐alkyl thiophene. Depending on the core heteroatom (O vs. N‐alkyl), ring junction (5,5‐exo vs. 6,6‐endo) and 3‐thiophene substituent (H vs. alkyl), two, three, four or six conformers are possible. All of these conformers were characterised by DFT and were found to be very close in energy at both IEFPCM/B3LYP/DGDZVP and SMD/M06/DGDZVP levels of theory. Within each conformer set, the HOMO and LUMO energies were within 0.05 eV and the predicted λmax values (TD‐DFT) within 10 nm, and this implies low sensitivity of the optical and electronic properties to conformation. Cyclic voltammetry measurements of selected compounds demonstrated good matching to the HOMO and LUMO energies from IEFPCM/B3LYP/DGDZVP computations. M06‐2X was the best DFT functional for TD‐DFT, giving predicted λmax values within about 20 nm.
Photochemically Initiated Oxidative Carbon–Carbon Bond‐Cleavage Reactivity in Chlorodiketonate NiII Complexes
Authors: Allpress Caleb J. , Arif Atta M. , Houghton Dylan T. , Berreau Lisa M. 
Published: December 2011

AbstractThree mononuclear NiII complexes containing a 2‐chloro‐1,3‐diketonate ligand and supported by the 6‐Ph2TPA chelate, as well as analogues that lack the 2‐chloro substituent on the β‐diketonate ligand, have been prepared and characterized. Upon irradiation at 350 nm under aerobic conditions, complexes containing the 2‐chloro‐substituted ligands undergo reactions to generate products resulting from oxidative cleavage, α‐cleavage, and radical‐derived reactions involving the 2‐chloro‐1,3‐diketonate ligand. Mechanistic studies suggest that the oxidative cleavage reactivity, which leads to the production of carboxylic acids, is a result of the formation of superoxide, which occurs through reaction of reduced nickel complexes with O2. The presence of the 2‐chloro substituent was found to be a prerequisite for oxidative carbon–carbon bond‐cleavage reactivity, as complexes lacking this functional group did not undergo these reactions following prolonged irradiation. The approach toward investigating the oxidative reactivity of metal β‐diketonate species outlined herein has yielded results of relevance to the proposed mechanistic pathways of metalloenzyme‐catalyzed β‐diketonate oxidative cleavage reactions.
Stakeholders' Influences on Corporate Green Innovation Strategy: A Case Study of Manufacturing Firms in China
Authors: Guoyou Qi , Saixing Zeng , Chiming Tam , Haitao Yin , Hailiang Zou 
Published: December 2011

ABSTRACTFacing the challenge of environmental degradation in China, a growing number of firms have begun to integrate environmental management systems into their business strategies and develop green innovation strategies. Based on the stakeholder theory, this paper attempts to explore the influences of stakeholders on the implementation of green process and green product innovation. Empirical results show that foreign customers play a significant role in driving companies to adopt strategy of green process and green product innovation. For foreign‐invested enterprises, the effect is limited to the adoption of green process innovation. It further reveals that community stakeholders and regulatory stakeholders have no significant effect on the corporate green process and green product innovation. Copyright © 2011 John Wiley & Sons, Ltd and ERP Environment.
Surrogate decision making for patients with end‐stage dementia
Authors: Jox Ralf J. , Denke Eva , Hamann Johannes , Mendel Rosmarie , Förstl Hans , Borasio Gian Domenico 
Published: December 2011

ObjectiveWe aim to explore how health surrogates of patients with dementia proceed in decision making, which considerations are decisive, and whether family surrogates and professional guardians decide differently.MethodsWe conducted an experimental vignette study using think aloud protocol analysis. Thirty‐two family surrogates and professional guardians were asked to decide on two hypothetical case vignettes, concerning a feeding tube placement and a cardiac pacemaker implantation in patients with end‐stage dementia. They had to verbalize their thoughts while deciding. Verbalizations were audio‐recorded, transcribed, and analyzed according to content analysis. By experimentally changing variables in the vignettes, the impact of these variables on the outcome of decision making was calculated.ResultsAlthough only 25% and 31% of the relatives gave their consent to the feeding tube and pacemaker placement, respectively, 56% and 81% of the professional guardians consented to these life‐sustaining measures. Relatives decided intuitively, referred to their own preferences, and focused on the patient's age, state of wellbeing, and suffering. Professional guardians showed a deliberative approach, relied on medical and legal authorities, and emphasized patient autonomy. Situational variables such as the patient's current behavior and the views of health care professionals and family members had higher impacts on decisions than the patient's prior statements or life attitudes.ConclusionsBoth the process and outcome of surrogate decision making depend heavily on whether the surrogate is a relative or not. These findings have implications for the physician–surrogate relationship and legal frameworks regarding surrogacy. Copyright © 2011 John Wiley & Sons, Ltd.
Neural correlates of creative writing: An fMRI Study
Authors: Shah Carolin , Erhard Katharina , Ortheil Hanns‐Josef , Kaza Evangelia , Kessler Christof , Lotze Martin 
Published: December 2011

AbstractCerebral activations involved in actual writing of a new story and the associated correlates with creative performance are still unexplored. To investigate the different aspects of the creative writing process, we used functional magnetic resonance imaging while 28 healthy participants performed a new paradigm related to creative writing: “brainstorming” (planning a story) and “creative writing” (writing a new and creative continuation of a given literary text), as well as an additional control paradigm of “reading” and “copying.” Individual verbal creativity was assessed with a verbal creativity test and creative performance with a qualitative rating of the creative products. “brainstorming” engaged cognitive, linguistic, and creative brain functions mainly represented in a parieto‐frontal‐temporal network, as well as writing preparation, and visual and imaginative processing. “creative writing” activated motor and visual brain areas for handwriting and additionally, cognitive and linguistic areas. Episodic memory retrieval, free‐associative and spontaneous cognition, and semantic integration were observed in a right lateralized activation pattern in bilateral hippocampi, bilateral temporal poles (BA 38), and bilateral posterior cingulate cortex in a “creative writing” minus “copying” comparison. A correlation analysis of “creative writing” minus “copying” with the creativity index revealed activation in the left inferior frontal gyrus (BA 45) and the left temporal pole (BA 38). Thus, verbal creativity during “creative writing” is associated with verbal and semantic memory as well as semantic integration. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.
Cellular properties of principal neurons in the rat entorhinal cortex. I. The lateral entorhinal cortex
Authors: Canto Cathrin B. , Witter Menno P. 
Published: December 2011

AbstractThe lateral entorhinal cortex (LEC) provides a major cortical input to the hippocampal formation, equaling that of the medial entorhinal cortex (MEC). To understand the functional contributions made by LEC, basic knowledge of individual neurons, in the context of the intrinsic network, is needed. The aim of this study is to compare physiological and morphological properties of principal neurons in different LEC layers in postnatal rats. Using in vitro whole cell current‐clamp recordings from up to four post hoc morphologically identified neurons simultaneously, we established that principal neurons show layer specific physiological and morphological properties, similar to those reported previously in adults. Principal neurons in L(ayer) I, LII, and LIII have the majority of their dendrites and axonal collaterals alone in superficial layers. LV contains mainly pyramidal neurons with dendrites and axons extending throughout all layers. A minority of LV and all principal neurons in LVI are neurons with dendrites confined to deep layers and axons in superficial and deep layers. Physiologically, input resistances and time constants of LII neurons are lower and shorter, respectively, than those observed in LV neurons. Fifty‐four percent of LII neurons have sag potentials, resonance properties, and rebounds at the offset of hyperpolarizing current injection, whereas LIII and LVI neurons do not have any of these. LV neurons show prominent spike‐frequency adaptation and a decrease in spike amplitudes in response to strong depolarization. Despite the well‐developed interlaminar communication in LEC, the laminar differences in the biophysical and morphological properties of neurons suggest that their in vivo firing patterns and functions differ, similar to what is known for neurons in different MEC layers. © 2011 Wiley Periodicals, Inc.
Significant deterioration in nanomechanical quality occurs through incomplete extrafibrillar mineralization in rachitic bone: Evidence from in-situ synchrotron X-ray scattering and backscattered electron imaging
Authors: Karunaratne Angelo , Esapa Christopher R , Hiller Jennifer , Boyde Alan , Head Rosie , Bassett JH Duncan , Terrill Nicholas J , Williams Graham R , Brown Matthew A , Croucher Peter I , Brown Steve DM , Cox Roger D , Barber Asa H , Thakker Rajesh V , Gupta Himadri S 
Published: December 2011

Abstract
Bone diseases such as rickets and osteoporosis cause significant reduction in bone quantity and quality, which leads to mechanical abnormalities. However, the precise ultrastructural mechanism by which altered bone quality affects mechanical properties is not clearly understood. Here we demonstrate the functional link between altered bone quality (reduced mineralization) and abnormal fibrillar-level mechanics using a novel, real-time synchrotron X-ray nanomechanical imaging method to study a mouse model with rickets due to reduced extrafibrillar mineralization. A previously unreported N-ethyl-N-nitrosourea (ENU) mouse model for hypophosphatemic rickets (Hpr), as a result of missense Trp314Arg mutation of the phosphate regulating gene with homologies to endopeptidase on the X chromosome (Phex) and with features consistent with X-linked hypophosphatemic rickets (XLHR) in man, was investigated using in situ synchrotron small angle X-ray scattering to measure real-time changes in axial periodicity of the nanoscale mineralized fibrils in bone during tensile loading. These determine nanomechanical parameters including fibril elastic modulus and maximum fibril strain. Mineral content was estimated using backscattered electron imaging. A significant reduction of effective fibril modulus and enhancement of maximum fibril strain was found in Hpr mice. Effective fibril modulus and maximum fibril strain in the elastic region increased consistently with age in Hpr and wild-type mice. However, the mean mineral content was ∼21% lower in Hpr mice and was more heterogeneous in its distribution. Our results are consistent with a nanostructural mechanism in which incompletely mineralized fibrils show greater extensibility and lower stiffness, leading to macroscopic outcomes such as greater bone flexibility. Our study demonstrates the value of in situ X-ray nanomechanical imaging in linking the alterations in bone nanostructure to nanoscale mechanical deterioration in a metabolic bone disease. © 2012 American Society for Bone and Mineral Research.