bluuebunny/crossref_metadata_2025 huggingface dataset:
Antagonist Effects of Veratric Acid against UVB-Induced Cell Damages
Authors: Shin Seoung , Jung Eunsun , Kim Seungbeom , Lee Kyung-Eun , Youm Jong-Kyung , Park Deokhoon
Published: May 2013

Ultraviolet (UV) radiation induces DNA damage, oxidative stress, and inflammatory processes in human epidermis, resulting in inflammation, photoaging, and photocarcinogenesis. Adequate protection of skin against the harmful effect of UV irradiation is essential. In recent years naturally occurring herbal compounds such as phenolic acids, flavonoids, and high molecular weight polyphenols have gained considerable attention as beneficial protective agents. The simple phenolic veratric acid (VA, 3,4-dimethoxybenzoic acid) is one of the major benzoic acid derivatives from vegetables and fruits and it also occurs naturally in medicinal mushrooms which have been reported to have anti-inflammatory and anti-oxidant activities. However, it has rarely been applied in skin care. This study, therefore, aimed to explore the possible roles of veratric acid in protection against UVB-induced damage in HaCaT cells. Results showed that veratric acid can attenuate cyclobutane pyrimidine dimers (CPDs) formation, glutathione (GSH) depletion and apoptosis induced by UVB. Furthermore, veratric acid had inhibitory effects on the UVB-induced release of the inflammatory mediators such as IL-6 and prostaglandin-E2. We also confirmed the safety and clinical efficacy of veratric acid on human skin. Overall, results demonstrated significant benefits of veratric acid on the protection of keratinocyte against UVB-induced injuries and suggested its potential use in skin photoprotection.
Synthesis, Characterization and Activity Evaluation of Matrinic Acid Derivatives as Potential Antiproliferative Agents
Authors: Chao Fan , Wang Dong-En , Liu Rui , Tu Qin , Liu Jian-Jun , Wang Jinyi
Published: May 2013

A series of new matrinic acid derivatives 5a–e was synthesized. The chemical structures of the synthesized compounds were confirmed by 1H-NMR, 13C-NMR, and electrospray ionization mass spectroscopy. The anti-tumor activities were also investigated in vitro by evaluating the effect of synthesized compounds on the proliferation of A375, A549, HeLa, and HepG2 cells. Compound 5e was found to be the most potent against A375 and HeLa cells, with IC50 values of 37 and 75.5 μg/mL, respectively. Compounds 5b, 5c, 5g, and 5h also exhibited antiproliferative activities against A549 cells, with IC50 values within the 36.2–47 μg/mL range. For HepG2 cells, 5e and 5i, with IC50 values of 78.9 and 61 μg/mL, respectively, showed higher antiproliferative activity than taxol.
Optimization and Characterization of Chitosan Films for Transdermal Delivery of Ondansetron
Authors: Can Aslı , Erdal Meryem , Güngör Sevgi , Özsoy Yıldız
Published: May 2013

The aim of this study was to develop novel transdermal films of ondansetron HCl with high molecular weight chitosan as matrix polymer and 2-(2-ethoxy-ethoxy) ethanol (Transcutol®) as plasticizer. In this context, firstly the physicochemical properties of gels used to formulate transdermal films were characterized and, physicochemical properties and bioadhesiveness of the transdermal films prepared with chitosan gels were assessed. The impact of three different types of terpenes, namely limonene, nerolidol and eucalyptol on in vitro skin permeation of ondansetron from transdermal films were also examined. ATR-FTIR measurements were performed to investigate the effects of the chitosan film formulations on in vitro conformational order of stratum corneum intercellular lipids after 24 h permeation study. The results showed that the chitosan gels consisting of Transcutol® as plasticizer and terpenes as penetration enhancer may be used to prepare transdermal films of ondansetron due to the good mechanical properties and bioadhesiveness of the transdermal films. Eucalyptol (1%) showed higher permeation enhancer effect than the other terpenes and control. ATR-FTIR data confirmed that finding in which eucalyptol induced a blue shift in the both CH2 asymmetric and symmetric absorbance peak positions indicating increased lipid fluidity of stratum corneum.
Nanostructured Biomaterials and Their Applications
Authors: Parratt Kirsten , Yao Nan
Published: May 2013

Some of the most important advances in the life sciences have come from transitioning to thinking of materials and their properties on the nanoscale rather than the macro or even microscale. Improvements in imaging technology have allowed us to see nanofeatures that directly impact chemical and mechanical properties of natural and man-made materials. Now that these can be imaged and quantified, substantial advances have been made in the fields of biomimetics, tissue engineering, and drug delivery. For the first time, scientists can determine the importance of nanograins and nanoasperities in nacre, direct the nucleation of apatite and the growth of cells on nanostructured scaffolds, and pass drugs tethered to nanoparticles through the blood-brain barrier. This review examines some of the most interesting materials whose nanostructure and hierarchical organization have been shown to correlate directly with favorable properties and their resulting applications.
Encapsulation of Hydrocortisone and Mesalazine in Zein Microparticles
Authors: Lau Esther , Giddings Steven , Mohammed Salmaan , Dubois Paul , Johnson Stuart , Stanley Roger , Halley Peter , Steadman Kathryn
Published: May 2013

Zein was investigated for use as an oral-drug delivery system by loading prednisolone into zein microparticles using coacervation. To investigate the adaptability of this method to other drugs, zein microparticles were loaded with hydrocortisone, which is structurally related to prednisolone; or mesalazine, which is structurally different having a smaller LogP and ionizable functional groups. Investigations into the in vitro digestibility, and the electrophoretic profile of zein, and zein microparticles were conducted to shed further insight on using this protein as a drug delivery system. Hydrocortisone loading into zein microparticles was comparable with that reported for prednisolone, but mesalazine loading was highly variable. Depending on the starting quantities of hydrocortisone and zein, the average amount of microparticles equivalent to 4 mg hydrocortisone, (a clinically used dose), ranged from 60–115 mg, which is realistic and practical for oral dosing. Comparatively, an average of 2.5 g of microparticles was required to deliver 250 mg of mesalazine (a clinically used dose), so alternate encapsulation methods that can produce higher and more precise mesalazine loading are required. In vitro protein digestibility revealed that zein microparticles were more resistant to digestion compared to the zein raw material, and that individual zein peptides are not preferentially coacervated into the microparticles. In combination, these results suggest that there is potential to formulate a delivery system based on zein microparticles made using specific subunits of zein that is more resistant to digestion as starting material, to deliver drugs to the lower gastrointestinal tract.
Combining Spatial Models for Shallow Landslides and Debris-Flows Prediction
Authors: Gomes Roberto , Guimarães Renato , De Carvalho, Júnior Osmar , Fernandes Nelson , Do Amaral Júnior Eurípedes
Published: May 2013

Mass movements in Brazil are common phenomena, especially during strong rainfall events that occur frequently in the summer season. These phenomena cause losses of lives and serious damage to roads, bridges, and properties. Moreover, the illegal occupation by slums on the slopes around the cities intensifies the effect of the mass movement. This study aimed to develop a methodology that combines models of shallow landslides and debris-flows in order to create a map with landslides initiation and debris-flows volume and runout distance. The study area comprised of two catchments in Rio de Janeiro city: Quitite and Papagaio that drained side by side the west flank of the Maciço da Tijuca, with an area of 5 km2. The method included the following steps: (a) location of the susceptible areas to landslides using SHALSTAB model; (b) determination of rheological parameters of debris-flow from the back-analysis technique; and (c) combination of SHALSTAB and FLO-2D models to delineate the areas more susceptible to mass movements. These scenarios were compared with the landslide and debris-flow event of February 1996. Many FLO-2D simulations were exhaustively made to estimate the rheological parameters from the back-analysis technique. Those rheological coefficients of single simulation were back-calculated by adjusting with area and depth of the debris-flow obtained from field data. The initial material volume in the FLO-2D simulations was estimated from SHALSTAB model. The combination of these two mathematical models, SHALSTAB and FLO-2D, was able to predict both landslides and debris-flow events. Such procedures can reduce the casualties and property damage, delineating hazard areas, to estimate hazard intensities for input into risk studies providing information for public policy and planning.
DNA Hairpins as Temperature Switches, Thermometers and Ionic Detectors
Authors: Jonstrup Anette , Fredsøe Jacob , Andersen Anni
Published: May 2013

Temperature is of major importance in most branches of science and technology as well as in everyday life, and with the miniaturization of electronic devices and the increasing ability to make research into small-scale systems, a specific need for very small thermostats and thermometers has been created. Here we describe how DNA molecules can be used as nanoscale sensors to meet these requirements. We illustrate how the hybridization kinetics between bases in DNA molecules combined with conformational changes of the DNA backbone can be exploited in the construction of simple but versatile temperature switches and thermometers, which can be built into electronic systems. DNA based sensors are at the same time applicable as ion detectors to monitor the chemical environment of a specific system.
Design of a Soil Cutting Resistance Sensor for Application in Site-Specific Tillage
Authors: Agüera Juan , Carballido Jacob , Gil Jesús , Gliever Chris , Perez-Ruiz Manuel
Published: May 2013

One objective of precision agriculture is to provide accurate information about soil and crop properties to optimize the management of agricultural inputs to meet site-specific needs. This paper describes the development of a sensor equipped with RTK-GPS technology that continuously and efficiently measures soil cutting resistance at various depths while traversing the field. Laboratory and preliminary field tests verified the accuracy of this prototype soil strength sensor. The data obtained using a hand-operated soil cone penetrometer was used to evaluate this field soil compaction depth profile sensor. To date, this sensor has only been tested in one field under one gravimetric water content condition. This field test revealed that the relationships between the soil strength profile sensor (SSPS) cutting force and soil cone index values are assumed to be quadratic for the various depths considered: 0–10, 10–20 and 20–30 cm (r2 = 0.58, 0.45 and 0.54, respectively). Soil resistance contour maps illustrated its practical value. The developed sensor provides accurate, timely and affordable information on soil properties to optimize resources and improve agricultural economy.
Current Trends in Wireless Mesh Sensor Networks: A Review of Competing Approaches
Authors: Rodenas-Herraiz David , Garcia-Sanchez Antonio-Javier , Garcia-Sanchez Felipe , Garcia-Haro Joan
Published: May 2013

Finding a complete mesh-based solution for low-rate wireless personal area networks (LR-WPANs) is still an open issue. To cope with this concern, different competing approaches have emerged in the Wireless Mesh Sensor Networks (WMSNs) field in the last few years. They are usually supported by the IEEE 802.15.4 standard, the most commonly adopted LR-WPAN recommendation for point-to-point topologies. In this work, we review the most relevant and up-to-date WMSN solutions that extend the IEEE 802.15.4 standard to multi-hop mesh networks. To conduct this review, we start by identifying the most significant WMSN requirements (i.e., interoperability, robustness, scalability, mobility or energy-efficiency) that reveal the benefits and shortcomings of each proposal. Then, we re-examine thoroughly the group of proposals following different design guidelines which are usually considered by end-users and developers. Among all of the approaches reviewed, we highlight the IEEE 802.15.5 standard, a recent recommendation that, in its LR-WPAN version, fully satisfies the greatest number of WMSN requirements. As a result, IEEE 802.15.5 can be an appropriate solution for a wide-range of applications, unlike the majority of the remaining solutions reviewed, which are usually designed to solve particular problems, for instance in the home, building and industrial sectors. In this sense, a description of IEEE 802.15.5 is also included, paying special attention to its efficient energy-saving mechanisms. Finally, possible improvements of this recommendation are pointed out in order to offer hints for future research.
Air-Coupled Piezoelectric Transducers with Active Polypropylene Foam Matching Layers
Authors: Gómez Alvarez-Arenas Tomás
Published: May 2013

This work presents the design, construction and characterization of air-coupled piezoelectric transducers using 1–3 connectivity piezocomposite disks with a stack of matching layers being the outer one an active quarter wavelength layer made of polypropylene foam ferroelectret film. This kind of material has shown a stable piezoelectric response together with a very low acoustic impedance (<0.1 MRayl). These features make them a suitable candidate for the dual use or function proposed here: impedance matching layer and active material for air-coupled transduction. The transducer centre frequency is determined by the l/4 resonance of the polypropylene foam ferroelectret film (0.35 MHz), then, the rest of the transducer components (piezocomposite disk and passive intermediate matching layers) are all tuned to this frequency. The transducer has been tested in several working modes including pulse-echo and pitch-catch as well as wide and narrow band excitation. The performance of the proposed novel transducer is compared with that of a conventional air-coupled transducers operating in a similar frequency range.
La régulation des ondes GSM
Authors: Deblander Caroline , Schiffino Nathalie
Published: May 2013

La Belgique est à la veille de voir se déployer sur son territoire la 4G, c’est-à-dire la quatrième génération de téléphonie portable. Celle-ci est présentée comme la technologie de l’avenir par l’industrie des télécommunications, car elle permettra la transmission de données à très haut débit (« Internet ultra-rapide »). Toutefois, le développement d’un nouveau réseau d’ondes GSM ne va pas sans poser diverses questions en termes d’urbanisme, d’environnement et de santé publique. L’implantation de nouvelles antennes-relais est souvent perçue négativement par la population, en raison de son impact paysager et, surtout, des effets potentiels des ondes électro-magnétiques sur l’organisme humain. Aujourd’hui, la régulation des ondes GSM par les pouvoirs publics est au centre de nombreux débats, en particulier à Bruxelles. Au début de l’année 2013, divers opérateurs ont estimé que les normes imposées par la Région bruxelloise sont trop restrictives pour permettre le déploiement de la 4G à Bruxelles, où la technologie est pourtant susceptible d’être utilisée à grande échelle. Le présent Courrier hebdomadaire dresse l’état des lieux des législations édictées par les trois régions du pays, en réservant une attention particulière à l’ordonnance bruxelloise du 1er mars 2007. Il rappelle aussi comment, au terme d’une action intentée devant la Cour constitutionnelle, la régulation de la téléphonie mobile a été reconnue compétence régionale en 2009.
« Dégage ! »
Authors: Meddeb Hind
Published: May 2013

En Tunisie, l’humour est décidément subversif. Que ce soit chez des activistes comme Azyz Amami, dans la musique du chanteur Bendirman ou les dessins de Nadia Khiari, c’est aussi l’humour qui a fait tomber Ben Ali. Aujourd’hui encore, caricaturistes et satiristes attaquent la volonté de censure, le conservatisme et l’hypocrisie d’Ennahda. En s’en prenant à la nouvelle omniprésence du sacré dans l’espace public, c’est le pluralisme qu’ils veulent défendre.
L'acharnement ironique
Authors: Peeters Benoît
Published: May 2013

La Belgique est un modèle réduit de la systématisation du geste ironique. Sa dissolution en direct lors d’une émission télévisée parodique en 2006 a donné lieu à de nombreuses réflexions sur les dangers de l’ironie. Celle-ci peut en effet être subversive, mais également devenir une sorte de réflexe, qui finit par détruire le discours politique et mener au nihilisme.
Mo Yan : se moquer sans faire de vagues
Authors: Link Perry , Béja Alice
Published: May 2013

L’attribution du prix Nobel de littérature à Mo Yan en 2012 a suscité de nombreuses controverses, souvent plus politiques que littéraires, sur le danger d’accorder un prix si prestigieux à un écrivain reconnu par les autorités chinoises. Car si Mo Yan, dans ses œuvres, manie le grotesque, le sarcasme et l’ironie, le résultat n’est pas une critique en profondeur mais un éclat de rire généralisé qui met sur le même plan victimes et bourreaux. Sans faire trop de vagues.
Hegel, Kierkegaard et l'ironie contemporaine
Authors: Fœssel Michaël
Published: May 2013

L’ironie est avant tout un jeu sur le langage, qui moque sa déconnexion d’avec le réel. L’ironiste, s’il ne propose pas de vision du monde alternative à celle qu’il critique, peut dès lors apparaître, ce que dénonce Hegel, comme en surplomb, occupé uniquement par lui-même. Mais il peut aussi être humble, et se contenter, comme le fit Socrate selon Kierkegaard, de débusquer les trop grandes certitudes à travers l’ignorance et le doute.
La dignité dans le débat sur la fin de vie
Authors: La Marne Paula
Published: May 2013

Les pistes actuellement à l’étude sur la fin de vie placent de nouveau la dignité au premier plan des considérations sur le mourir. Mais que signifie ce terme, selon qu’il est employé par les soins palliatifs, ou par les partisans de la mort volontaire ?
Pour une approche explicative et une pratique raisonnée de l'anglais
Authors: Rapatel Philippe
Published: May 2013

L’apprentissage et la pratique d’une langue se sont longtemps appuyés sur l’application de règles grammaticales qui ne laissaient aucune initiative à l’apprenant. Nous avons tenté de mettre en évidence l’intérêt d’une approche explicative et énonciative qui induirait une réflexion sur les mécanismes internes à l’anglais ainsi qu’au français dans une démarche contrastive.
Croyance, idéologie et apprentissage
Authors: Joncheray Marie-Françoise
Published: May 2013

Fondées sur la théorie de la modifiabilité structurelle cognitive de Feuerstein, de récentes recherches expérimentales semblent confirmer scientifiquement que le parti pris d’une attitude résolument optimiste et confiante favorise les apprentissages.
Renewal and reconstruction: Holy Writ in Ezra-Nehemiah – A missional reading
Authors: Wielenga Bob
Published: May 2013

In this article we investigate the missional potential of the two-volume book of Ezra-Nehemiah. We contend that the written word of God is a transforming power in society through the mediation of the church. This implies that spiritual renewal precedes social reconstruction. We examine this book historically, canonically and exegetically to lay a foundation for a missiological reflection on the results of this excursion in the field of biblical studies. We close with the formulation of some missional conclusions that serve as guidelines for the development of a relevant theology of mission.In hierdie artikel ondersoek ons die missionêre moontlikhede van die tweedelige boek Esra-Nehemia. Ons stel dat die geskrewe woord van God ’n hervormende krag in die samelewing is deur die bemiddeling van die kerk. Dit impliseer dat geestelike vernuwing sosiale rekonstruksie voorafgaan. Ons doen historiese, kanoniese en eksegetiese ondersoek na die boek om ’n grondslag te lê vir ’n missiologiese beskouing van die resultate van hierdie ekskursie in die Bybelwetenskapveld. Ons sluit af met die formulering van missionêre gevolgtrekkings om te dien as wegwysers vir die ontwikkeling van ’n toepaslike sendingsteologie.
A Fast Accurate Boundary Integral Method for Potentials on Closely Packed Cells
Authors: Ying Wenjun , Beale J. Thomas
Published: May 2013

Boundary integral methods are naturally suited for the computation of harmonic functions on a region having inclusions or cells with different material properties. However, accuracy deteriorates when the cell boundaries are close to each other. We present a boundary integral method in two dimensions which is specially designed to maintain second order accuracy even if boundaries are arbitrarily close. The method uses a regularization of the integral kernel which admits analytically determined corrections to maintain accuracy. For boundaries with many components we use the fast multipole method for efficient summation. We compute electric potentials on a domain with cells whose conductivity differs from that of the surrounding medium. We first solve an integral equation for a source term on the cell interfaces and then find values of the potential near the interfaces via integrals. Finally we use a Poisson solver to extend the potential to a regular grid covering the entire region. A number of examples are presented. We demonstrate that increased refinement is not needed to maintain accuracy as interfaces become very close.
Age and Gender Differences in Job Opportunities
Authors: Humpert Stephan
Published: May 2013

There are only a few pieces of literature on age-specific occupational segregation. In this descriptive paper, I focus on occupational opportunities for newly-hired older male and female workers. This study is an enriched replication study of Hutchens (ILRR, 1988), who showed that firms employ older workers, but hire them less often than they hire younger ones. I use a rich dataset for West Germany with information covering almost thirty years, the regional file of the IAB Employment Sample (IABS-R04). By drawing segregation curves and calculating different measures, such as the Dissimilarity Index and the Hutchens Square Root Segregation Index, I find clear evidence that age-related segregation exists. While newly-hired workers in the age groups of 18 to 34 years and 35 to 54 years are quite similarly distributed in terms of the indices, those in the oldest age group, aged 55 years and above, and especially older women, are more segregated. Differences for older male and female workers over time may be explained by changes in labor and retirement policies.
The Fiscal Pressure Endured by Trading Companies
Authors: Cucoşel Constantin
Published: May 2013

In order to carry out the extremely complex and diverse tasks it has to perform, the state needs important financial resources it can obtain either from within the country, from its taxpayers, physical persons or legal entities, or from external sources when internal resources are insufficient. The society cannot exist in the absence of the duties and taxes whose necessity is, on one hand stipulated by the Constitution, and on the other, proved by historical reality. It is only logical for these taxes to be imposed to the taxpayers. Fiscal pressure is a concept closely related to the notion of taxation and is often used to describe its level.   Keywords: taxes, fees, taxation, fiscal pressure, tax evasion
Identification of the Problems Faced by Exceptional Children at Primary level in Khyber Pakhtunkhwa (Pakistan)
Authors: Suleman Qaiser , Hussain Ishtiaq , Nisa Zaib-Un-
Published: May 2013

The purpose of the study was to identify the problems faced by exceptional children at primary level in Khyber Pakhtunkhwa. All the government institutions for persons with disabilities in Khyber Pakhtunkhwa constituted the population of the study. The study was delimited to physically handicapped students only. The study was further delimited to seven government institutions for persons with disabilities. From each institute, five teachers and ten students were randomly selected. The study was descriptive in nature therefore a single questionnaire was developed as research instrument for the collection of data. Data was collected through personal visits. After collection of the data, it was organized, tabulated, analyzed and interpreted. Percentage and chi square were applied for the statistical treatment of the data. After statistical analysis of the data, the researchers concluded that curriculum was not designed to meet the needs of special children. Special children were not being taught according to Individualized Educational Programme (I.E.P). Basic educational facilities were not available. Mobility aids were not present in the institutions. Therefore it is strongly recommended that special children should be taught through individualized educational programmes to strengthen their educational attainment. Curriculum should be designed according to the needs of the special children. Mobility aids i.e., crutches, wheelchairs, artificial limbs etc should be provided to each special education institution on priority basis. KEYWORDS: Identification, Problems, Exceptional Children, Primary Level
Extracorporeal Membrane Oxygenation Cannula Malposition in the Azygos Vein in an Infant
Authors: Balmaks Reinis , Sufficool Kari E. , White Frances V. , Byrge Melissa M. , Kolovos Nikoleta S.
Published: May 2013

Introduction

Misplacement of extracorporeal membrane oxygenation (ECMO) venous cannula in the azygos vein has previously been described only in newborns.

Case

For the first time, we report an aberrant ECMO cannula placement in the azygos vein in a child outside neonatal period. History of chronic lung disease and ligation of persistent ductus arteriosus leading to elevated right ventricular pressure was the potential risk factor.

Conclusions

This rare complication should be considered whenever the patient has inadequate venous return on ECMO and it can be easily ruled out with a lateral chest radiograph.
Intravesical Chemotherapy
Authors: Curotto Antonio Gerardo
Published: May 2013

Bladder cancer care continues to represent a significant financial burden on the population and on the healthcare system. The incidence of bladder cancer has increased over the last two decades. Therapeutic advances have occurred in bladder cancer care, but at an increased cost to payers, providers, and patients. Intravesical treatment of non-muscle invasive tumors represents one of the main costs. For this reason therapeutic schedules need to be rationalized. In this perspective, we present some critical remarks on: the use of gemcitabine in clinical practice; the real impact of the perioperative chemotherapy, emphasizing the cost and effectiveness in high-risk patients, and finally the optimization of intravesical treatments.

There is a need for the scientific community to focus on their resources and convey efforts not in the treatment of low-risk cancers (present in significant numbers in various studies), which the Anglo-Saxons call “nuisance tumor” since they can be treated easily and effectively at low cost, but definitely to engage in the study of the treatment of cancer at high risk of recurrence and progression, and it is on this field that the cost (economic, management, subjective) / benefit ratio must be assessed.
African Politics and Moral Vision
Authors: Hoekema David A.
Published: May 2013

Political life without common ideals or a compelling vision of the future loses its vitality and descends into a predatory struggle—a danger all too often evident in postcolonial Africa. Yet in the era of liberation, a distinctly African political and philosophical ideal emerged, a hybrid philosophy of nationhood that drew on three distinct sources: Western ideals of democracy and the rule of law, a socialist vision of mutual aid and responsibility, and the vitality of African communitarian traditions. It was also a deeply religious vision, in ways seldom acknowledged even by its adherents. After review of recent developments in Ghana, Kenya, and South Africa, it is suggested that a distinctively African political and economic order may still be available as a guiding vision for African nations.
Erotic Perfectionism in Jewish Rationalist Philosophy
Authors: Strawser Michael
Published: May 2013

It is a view commonly held that within the Jewish rationalist tradition epitomized by Baruch Spinoza the snares of erotic love are something that a rational person would actively seek to avoid. But is love a thing for fools? Is this truly the view of Spinoza and the rationalist tradition in medieval Jewish philosophy that he inherited, or can we find a way to conceive of erotic love that accords with the life of reason? In this article I will attempt to answer these questions within the context of an analysis of Isaac Bashevis Singer's “The Spinoza of Market Street” and by considering the erotic perfectionist ethic as it is expressed primarily in Saadia Gaon's Book of Beliefs and Opinions and Spinoza's Ethics. I will show that the significant points of convergence and divergence between these two thinkers serve to illuminate our thinking about erotic perfectionism. Both Saadia and Spinoza are careful, systematic Jewish thinkers developing ethical theories in which reason plays a pronounced role in cultivating a virtuous life. Consequently, like other ethicists for whom the virtues are key, both Saadia and Spinoza are intent on expressing the ideal human conduct of the moral exemplar. In just what way does erotic love fit into the ideal human life?
Algunos desafíos a enfrentar en la modelación hidrológica
Authors: Ávalos Lingán Roberto Fredy
Published: May 2013

El diseño y la operación de obras hidráulicas requieren, por lo general, información de caudales de un periodo largo. En nuestro país las series largas no son comunes, más aun si el sitio de interés no coincide con la red nacional de mediciones. El hidrólogo se ve con la necesidad de modelar el proceso hidrológico para poder responder a los requerimientos. El objetivo de la presente investigación es descubrir y poner a la luz algunos inconvenientes que pueden ocurrir y complicar la modelación hidrológica, situación que es común en nuestro país. La primera parte de la investigación consiste en el análisis del comportamiento de la relación lámina de lluvia de la cuenca con los caudales por diferentes pasos de tiempo (de 1 día a 30 días), donde las magnitudes de las láminas y de los caudales fueron determinados mediante el procedimiento de la media móvil. La otra parte de la investigación es la aplicación de modelos hidrológicos conceptuales para observar el efecto de dicha relación en el resultado de la modelación. Se concluye que para las cuencas investigadas la relación lámina de lluvia–caudal observado tiende a aumentar conforme aumenta el paso de tiempo. Para el caso de 1 día el éxito de los resultados de la modelación está relacionado con el comportamiento de la relación lluvia–caudal. DOI: http://dx.doi.org/10.5377/rct.v0i10.1065 Revista Ciencia y Tecnología, No. 10, junio 2012 pp 100-116
Producción de bioetanol a partir del mucilago de café (Coffea arabica. L). CURC. UNAH. Comayagua. Honduras. 2011
Authors: Gonzales Hamsy Maradiaga , Banegas Carlos Luis , Funes Caballero Mario Renan , Osorio Rivera Melsar Enoc , Henríquez Flores Nelson Daniel , Eloy Néstor , Mejía Nicolás
Published: May 2013

La obtención de bioetanol a partir del mucilago de café, el cual es un producto de desecho que es arrojado a corrientes de agua, sin tratamiento alguno, ya que el productor no cuenta con alternativas de uso, causando graves problemas de contaminación. El estudio detalla acerca del aprovechamiento de mucilago generado durante el proceso de beneficiado del fruto, siendo los lugares de estudio La Libertad, en el Departamento de Comayagua y Marcala, en el Departamento de La Paz. Los dos métodos de fermentación utilizado son: en el método controlado se inocularon tres muestras, cada una con diferentes grados brix de 2000 mililitros de mucilago+2%Peso/Peso, 2000 mililitros de mucilago+4%Peso/Peso y 2000 mililitros de mucilago+6%Peso/Peso de Saccharomyces cerevisae y el método no controlado sin inoculación de levadura, en el cual se utilizaron tres muestras de 2000 mililitros con diferentes grados Brix. Para cada uno de los métodos se destilaron 800 mililitros haciendo dos repeticiones de cada una de las muestras. Los análisis realizados demuestran que existen factores que influyen para obtener rendimientos satisfactorios: la altura, concentración de azúcar, beneficiado del café y métodos de inoculación, entre otros. Con esto también se pretende sensibilizar a instituciones involucradas en la extensión rural y a los productores de café, en la implementación del bioetanol como fuente de energía alterna, como combustible de automóviles y otros usos de beneficio humano, y al mismo tiempo dar respuesta al problema ambiental que representan las aguas mieles de café (mucilago) en las distintas zonas de nuestro país. DOI: http://dx.doi.org/10.5377/rct.v0i10.1068 Revista Ciencia y Tecnología, No. 10, junio 2012 pp 150-164
Estímulos a la investigación científica de la UNAH: Un mecanismo de promoción y desarrollo de la actividad investigativa
Authors: Barahona Miguel
Published: May 2013

DOI: http://dx.doi.org/10.5377/rct.v0i11.1070 Revista Ciencia y Tecnología, No. 11, diciembre 2012 pp 13-16
Incubadoras en ambientes virtuales basadas en gestión de proyectos: Potenciando incubadoras de ciencia y emprendimiento, un aporte desde la academia
Authors: Aguilar Romero Marvin Josué , Rodríguez García José Luis
Published: May 2013

Para poder transmitir la cultura de la investigación y el emprendedurismo es necesario hacer partícipe a las personas interesadas en el desarrollo de iniciativas de emprendimiento y de proyectos de investigación científica, el modelo presentado a continuación plantea el uso de una incubadora virtual que, basándose en la gestión de proyectos, promete a los estudiantes obtener las competencias deseadas en emprendimiento y en investigación así como aumentar la producción científica de los países cuyas instituciones de educación superior hagan uso de las mismas. Las salidas científicas alimentan a los proyectos de emprendimiento así como las diversas actividades de un emprendimiento alimentan a los proyectos de investigación para asegurar la calidad del producto final, así ambas incubadoras se complementan para duplicar la cantidad de salidas obtenidas y el enfoque modular brindado por la gestión de proyectos permite la integración multidisciplinaria en cada una de las tres fases del proceso de incubación: pre-incubación, incubación y postincubación. DOI: http://dx.doi.org/10.5377/rct.v0i11.1071 Revista Ciencia y Tecnología, No. 11, diciembre 2012 pp 19-28
Proyecto de investigación con primer grado “Pedagogía de la ternura”
Authors: Pineda Flores Alma Ondina
Published: May 2013

En busca de respuestas y haciendo investigación nos encontramos que nuestra realidad educativa está inmersa en múltiples problemas dentro y fuera de las aulas de clase (lecturas de sociología UPN-2,000), donde todos y todas los que intervienen en el proceso de enseñanza-aprendizaje tenemos un compromiso para mejorar la calidad de la educación, como docente sé que puedo contribuir con un granito de arena ayudando y comprometiéndome con cada uno de mis alumnos y para ello hago lo siguiente: 1. Hacer un diagnóstico, 2. Elaborar un plan de intervención Basado en la “Pedagogía de la Ternura” tomando en primer momento este concepto de Restrepo 2000. El cual hace referencia a: · La diferencia entre el ser humano y la máquina, todos sabemos que las máquinas realizan operaciones admirables, con mucha mayor exactitud que las que pueden realizar un niño o un ser humano. Si yo tuviera que describir de manera general lo que acontece en el mundo contemporáneo diría que tenemos un excelente desarrollo tecnológico pero un impresionante analfabetismo afectivo. Tomando en cuenta lo anterior y además otros temas afines como: · La gramática de la ternuraTeorías del desarrollo psicológico y el aprendizaje social de: a) Erick Erickson b) Jean Piaget c) Albert Bandura d) Lev Semyonovich Vygotsky · Teorías de la inteligencia emocional de: a) Myriam Pulg b) Lawrence E. Shapiro c) Doris Martin y Karin Boeck DOI: http://dx.doi.org/10.5377/rct.v0i11.1073 Revista Ciencia y Tecnología, No. 11, diciembre 2012 pp 45-60
Detección de cambios en la cobertura de la tierra de un sector del occidente de Honduras Período 1991 - 2006
Authors: Pineda de Carías María Cristina , Ochoa Vilma Lorena , Enríque Corrales Rafael
Published: May 2013

Disponer de un conjunto de imágenes clasificadas por cobertura de la tierra de varios años, habiendo utilizado la misma metodología científica para todas ellas, hace que los datos y los cambios detectados en cuanto a incrementos o decrementos de cualquiera de las clases sean homogéneos, comparables y por tanto más confiables. El objetivo de este trabajo fue detectar, a partir del estudio de cuatro imágenes satelitales LandSat de diferentes fechas, los principales cambios en la cobertura de la tierra de un sector del occidente de Honduras, en un periodo de quince años que abarcó, siete y medio años antes y después del Huracán Mitch. La metodología empleada incluyó, desde la selección de las imágenes de fechas y características apropiadas; el pre procesamiento para realizar correcciones geométricas y radiométricas; la delimitación del área de estudio y acopio de información relevante de la zona; la obtención de una leyenda basada en el Sistema de Clasificación de Cobertura de la Tierra de la FAO-UNEP; la realización de clasificación supervisada de las cuatro imágenes; la verificación de resultados mediante el uso de radiometría de campo y de técnicas estadísticas; terminando con el análisis multitemporal para la detección de cambios. Como principales resultados: se comparó la reflectancia calculada a partir de las imágenes LandSat con la reflectancia medida con un radiómetro de campo; se elaboró cartografía de la clasificación supervisada de los años de 1991, 1995, 2003 y 2006; y se cuantificaron los cambios en la cobertura de la tierra, antes y después de Mitch. Conclusión importante fue, el marcado avance de la frontera agrícola a expensas de la disminución de la cobertura de bosques del sector, acompañado por otro lado de la recuperación del bosque, especialmente de pino, a partir de coberturas de matorrales, pastos y suelo desnudo. DOI: http://dx.doi.org/10.5377/rct.v0i11.1075 Revista Ciencia y Tecnología, No. 11, diciembre 2012 pp 78-109
Multi-Robot Coordination in Complex Environment with Task and Communication Constraints
Authors: Liu Yabo , Yang Jianhua , Zheng Yao , Wu Zhaohui , Yao Min
Published: May 2013

Abstract The tasks would fail to be assigned to any robots in the task allocation phase as a consequence of the inherent communication constraints in multi-robot systems (MRS). This negative effect becomes even more serious in tasks with temporal constraints. We therefore propose the constraint-based approach (CoBA), a market-based task allocation approach to enable multi-robot coordination in domains with temporal constraints between subtasks of a complex task and network constraints between robots. We handle network constraints by having each robot maintain a dynamic acquaintance network of robots that it knows about, and allowing a robot to submit a bid on behalf of another robot during a task auction (“indirect bidding”). In order to model the complex task, we introduce the AND/OR task tree with temporal constraints. An auction-clearing routine, which supports the AND/OR task tree with temporal constraints and direct/indirect task auction, is proposed to enable effective multi-robot task allocation in spite of various constraints. The solution was validated in both simulation and physical environments by a series of experiments in disaster response domains. Specifically, we study the system performance by separately varying the number of robots, the expected rate of task issuance, the communication reliability factor, the compositions of MRS, as well as the acquaintance relationship parameter, in simulation experiments. The results suggest that our solution outperforms others, that is, robots were able to complete the tasks more promptly and effectively.
The Inverted Pendulum Benchmark in Nonlinear Control Theory: A Survey
Authors: Boubaker Olfa
Published: May 2013

Abstract For at least fifty years, the inverted pendulum has been the most popular benchmark, among others, in nonlinear control theory. The fundamental focus of this work is to enhance the wealth of this robotic benchmark and provide an overall picture of historical and current trend developments in nonlinear control theory, based on its simple structure and its rich nonlinear model. In this review, we will try to explain the high popularity of such a robotic benchmark, which is frequently used to realize experimental models, validate the efficiency of emerging control techniques and verify their implementation. We also attempt to provide details on how many standard techniques in control theory fail when tested on such a benchmark. More than 100 references in the open literature, dating back to 1960, are compiled to provide a survey of emerging ideas and challenging problems in nonlinear control theory accomplished and verified using this robotic system. Possible future trends that we can envision based on the review of this area are also presented.
Design and Assessment of a Machine Vision System for Automatic Vehicle Wheel Alignment
Authors: Furferi Rocco , Governi Lapo , Volpe Yary , Carfagni Monica
Published: May 2013

Abstract Wheel alignment, consisting of properly checking the wheel characteristic angles against vehicle manufacturers' specifications, is a crucial task in the automotive field since it prevents irregular tyre wear and affects vehicle handling and safety. In recent years, systems based on Machine Vision have been widely studied in order to automatically detect wheels' characteristic angles. In order to overcome the limitations of existing methodologies, due to measurement equipment being mounted onto the wheels, the present work deals with design and assessment of a 3D machine vision-based system for the contactless reconstruction of vehicle wheel geometry, with particular reference to characteristic planes. Such planes, properly referred to as a global coordinate system, are used for determining wheel angles. The effectiveness of the proposed method was tested against a set of measurements carried out using a commercial 3D scanner; the absolute average error in measuring toe and camber angles with the machine vision system resulted in full compatibility with the expected accuracy of wheel alignment systems.
Efficient Data Reduction Techniques for Remote Applications of a Wireless Visual Sensor Network
Authors: Khursheed Khursheed , Imran Muhammad , Ahmad Naeem , O'Nils Mattias
Published: May 2013

Abstract A Wireless Visual Sensor Network (WVSN) is formed by deploying many Visual Sensor Nodes (VSNs) in the field. After acquiring an image of the area of interest, the VSN performs local processing on it and transmits the result using an embedded wireless transceiver. Wireless data transmission consumes a great deal of energy, where energy consumption is mainly dependent on the amount of information being transmitted. The image captured by the VSN contains a huge amount of data. For certain applications, segmentation can be performed on the captured images. The amount of information in the segmented images can be reduced by applying efficient bi-level image compression methods. In this way, the communication energy consumption of each of the VSNs can be reduced. However, the data reduction capability of bi-level image compression standards is fixed and is limited by the used compression algorithm. For applications attributing few changes in adjacent frames, change coding can be applied for further data reduction. Detecting and compressing only the Regions of Interest (ROIs) in the change frame is another possibility for further data reduction. In a communication system, where both the sender and the receiver know the employed compression standard, there is a possibility for further data reduction by not including the header information in the compressed bit stream of the sender. This paper summarizes different information reduction techniques such as image coding, change coding and ROI coding. The main contribution is the investigation of the combined effect of all these coding methods and their application to a few representative real life applications. This paper is intended to be a resource for researchers interested in techniques for information reduction in energy constrained embedded applications.
Conceptual Framework for Knowledge-Based Decision Migration in Multi-Component Robots
Authors: Rai Laxmisha , Hong Jiman
Published: May 2013

Abstract This paper presents a conceptual framework for dynamically migrating the decisions of multi-component robots within different physical subcomponents. At the higher layer, a decision-making distributed migration system embeds the rules written in a knowledge-based system (KBS). The rules are written and decisions are made at one component, which can be migrated by the underlying distributed system. This eventually results in intelligent migration of the decisions and robot survival, irrespective of a particular physical component failure. Moreover, a robot does not need an exclusive control system for each component. The implementation is a two-step process. Initially, component-specific facts are identified and mapped to suit to respective components and to write rules and explore different gestures and behaviour of the robot. The second step is the embedding of these rules within the distributed or agent-based system and allowing the decisions to float around the system. The Jess (Java Expert System Shell) expert system is used as the knowledge-based tool and different gestures are generated to realize the proposed method.
An Optimized Field Coverage Planning Approach for Navigation of Agricultural Robots in Fields Involving Obstacle Areas
Authors: Hameed Ibrahim A. , Bochtis Dionysis , Sørensen Claus A.
Published: May 2013

Abstract Technological advances combined with the demand of cost efficiency and environmental considerations has led farmers to review their practices towards the adoption of new managerial approaches, including enhanced automation. The application of field robots is one of the most promising advances among automation technologies. Since the primary goal of an agricultural vehicle is the complete coverage of the cropped area within a field, an essential prerequisite is the capability of the mobile unit to cover the whole field area autonomously. In this paper, the main objective is to develop an approach for coverage planning for agricultural operations involving the presence of obstacle areas within the field area. The developed approach involves a series of stages including the generation of field-work tracks in the field polygon, the clustering of the tracks into blocks taking into account the in-field obstacle areas, the headland paths generation for the field and each obstacle area, the implementation of a genetic algorithm to optimize the sequence that the field robot vehicle will follow to visit the blocks and an algorithmic generation of the task sequences derived from the farmer practices. This approach has proven that it is possible to capture the practices of farmers and embed these practices in an algorithmic description providing a complete field area coverage plan in a form prepared for execution by the navigation system of a field robot.