bluuebunny/crossref_metadata_2025 huggingface dataset:
Introduction to Plasma Based Propulsion System: Hall Thrusters
Authors: Singh Sukhmander , Kumar Sanjeev , Kumar Meena Shravan , Kumar Saini Sujit
Published: April 2021

Technically, there are two types of propulsion systems namely chemical and electric depending on the sources of the fuel. Electrostatic thrusters are used for launching small satellites in low earth orbit which are capable to provide thrust for long time intervals. These thrusters consume less fuel compared to chemical propulsion systems. Therefore for the cost reduction interests, space scientists are interested to develop thrusters based on electric propulsion technology. This chapter is intended to serve as a general overview of the technology of electric propulsion (EP) and its applications. Plasma based electric propulsion technology used for space missions with regard to the spacecraft station keeping, rephrasing and orbit topping applications. Typical thrusters have a lifespan of 10,000 h and produce thrust of 0.1–1 N. These devices have E→×B→ configurations which is used to confine electrons, increasing the electron residence time and allowing more ionization in the channel. Almost 2500 satellites have been launched into orbit till 2020. For example, the ESA SMART-1 mission (Small Mission for Advanced Research in Technology) used a Hall thruster to escape Earth orbit and reach the moon with a small satellite that weighed 367 kg. These satellites carrying small Hall thrusters for orbital corrections in space as thrust is needed to compensate for various ambient forces including atmospheric drag and radiation pressure. The chapter outlines the electric propulsion thruster systems and technologies and their shortcomings. Moreover, the current status of potential research to improve the electric propulsion systems for small satellite has been discussed.
Surgical Treatment of Wounds Using Stem Cells in Epidermolysis Bullosa (EB)
Authors: Nita Magdalena , Pliszczyński Jacek , Eljaszewicz Andrzej , Moniuszko Marcin , Ołdak Tomasz , Woźniak Katarzyna , Majewski Sławomir , Kowalewski Cezary , Kamiński Artur , Śladowski Dariusz , Zimek Zbigniew , Kosieradzki Maciej , Fiedor Piotr
Published: April 2021

Epidermolysis bullosa (EB) is a group of hereditary skin diseases, or genodermatoses, characterized by the formation of severe, chronic blisters with painful and life-threatening complications. Despite the previous and ongoing progress in the field, there are still no effective causative treatments for EB. The treatment is limited to relieving symptoms, which—depending on disease severity—may involve skin (blisters, poorly healing wounds caused by the slightest mechanical stimuli, contractures, scarring, pseudosyndactyly) and internal organ abnormalities (esophageal, pyloric, or duodenal atresia; renal failure; and hematopoietic abnormalities). The last decade saw a series of important discoveries that paved the way for new treatment methods, including gene therapy, bone marrow transplantation, cell therapy (allogenic fibroblasts, mesenchymal stem cells [MSCs], and clinical use of induced pluripotent stem cells. Tissue engineering experts are attempting to develop skin-like structures that can facilitate the process of healing to promote skin reconstruction in injuries that are currently incurable. However, this is incredibly challenging, due to the complex structure and the many functions of the skin. Below, we characterize EB and present its potential treatment methods. Despite the cure for EB being still out of reach, recent data from animal models and initial clinical trials in humans have raised patients’, clinicians’, and researchers’ expectations. Consequently, modifying the course of the disease and improving the quality of life have become possible. Moreover, the conclusions drawn based on EB treatment may considerably improve the treatment of other genetic diseases.
The Structure of Leukocyte Sialic Acid-Containing Membrane Glycoconjugates is a Differential Indicator of the Development of Diabetic Complications
Authors: Brodyak Iryna , Sybirna Natalia
Published: April 2021

Glycans, as potential prognostic biomarkers, deserve attention in clinical glycomics for diseases diagnosis. The variety of glycan chains, attached to proteins and lipids, makes it possible to form unique glycoconjugates with a wide range of cellular functions. Under leukocyte-endothelial interaction, not only the availability of glycoconjugates with sialic acids at the terminal position of glycans are informative, but also the type of glycosidic bond by which sialic acids links to subterminal carbohydrates in structure of glycans. The process of sialylation of leukocyte glycoconjugates undergoes considerable changes in type 1 diabetes mellitus. At early stage of disease without diabetic complications, the pathology is accompanied by the increase of α2,6-linked sialic acids. The quantity of sialic acid-containing glycoconjugates on leukocytes surface increases in condition of disease duration up to five years. However, the quantity of sialic acids linked by α2,6-glycosidic bonds decreases in patients with the disease duration over ten years. Therefore, sialoglycans as marker molecules determine the leukocyte function in patients with type 1 diabetes mellitus, depending on the disease duration. Changes in the glycans structure of membrane glycoconjugates of leukocytes allow understanding the mechanism of diabetic complications development.
Safe Adaptive Trajectory Tracking Control of Robot for Human-Robot Interaction Using Barrier Function Transformation
Authors: Salehi Iman , Rotithor Ghananeel , Dani Ashwin
Published: April 2021

In this chapter, safety methods in human-robot (HR) interaction/collaboration are presented. Ensuring the safety of humans, objects, or even the robot itself in the robot’s operating environment is one of the crucial aspects of collaborative robotics. Since there are limited ways of controlling the behavior of humans, e.g., by placing physical barriers, shaping the behavior of the robot is a feasible option. The chapter discusses current methods of placing barriers for human safety in an industrial setting and novel methods of placing virtual barriers by designing robot controllers using barrier transformation. The concepts of barrier functions (BFs), control barrier functions (CBFs), and barrier transformations are reviewed. The barrier transformation concept is used to design an adaptive trajectory tracking controller for the robot such that the robot does not cross the virtual barriers. The designed controller is tested in simulations. Future directions of safety technology in human-robot collaboration are presented.
Psychosocial Aspects of Glaucoma
Authors: Dayal Ashutosh
Published: April 2021

Glaucoma, not only leads to irreversible visual impairment, but also has a negative impact on Quality of Life of the patients. Visual disability, lifelong medical and surgical treatments and even the mere knowledge of having an irreversible potentially blinding condition tend to cause severe psychological stress in patients, leading to negative emotions such as anxiety or depression. The goal of glaucoma treatment should not be limited to preserving the vision, but also address the psychological aspects and preservation of patient wellbeing. Patient counselling, right from at the time of diagnosis, periodic psychological assessment and creating awareness in the society as a whole should be implemented as a part of holistic approach to glaucoma. Utilisation of Patient- reported quality of life tools would help clinicians in more closely understanding the problems and would, in turn, aid in providing comprehensive customised treatment option for each patient.
New Perspective of Nano Fibers: Synthesis and Applications
Authors: Sista Deepthi
Published: April 2021

Nano fibers are most attractive materials in the scientific world due to their enormous applications in various fields. Their applications start with generation of energy, solution to environmental problems and continues with medical field and many more. Nano materials got much importance from their peculiar electrical, optical, mechanical and thermal properties. Fibrous materials are obtained from several sources and by different mechanisms these materials are converted into nano materials. As of bulk fibers include specific properties compared to other materials, the generation of nano fibers enhance all the properties. The synthesis of nano fibers from natural and synthetic polymers, metals, semiconductors, composite materials, carbon based materials lead to new perspective in science and engineering fields. Most pronouncing techniques that include conventional and modern methods are available to fabricate nano fibers from these materials. Of them some are being used from a long time and some are emerging techniques to generate flexible substrates. Electrospinning, template based synthesis, polymerization, self-assembly, sonochemical synthesis are the conventional methods for the production of nano fibers. New technologies include electro hydrodynamic writing, plasma induced synthesis, centrifugal jet spinning, CO2 laser supersonic marks a trend in development of nano fibrous materials. This chapter give details about fabrication materials and provides synthetic routes to generate them along with applications. Also this chapter focuses on the challenges in development of nano fiber technology in commercial perspective.
A silvicultura do eucalipto na Região Geográfica Intermediária de Araguaína: implicações socioespaciais sob a ótica do meio técnico-científico-informacional
Authors: Guedes Luciano Da Silva , Trindade Júnior Saint-Clair Cordeiro da
Published: April 2021

O presente artigo tem como objetivo abordar a expansão e as implicações socioespaciais do eucalipto na Região Geográfica Intermediária de Araguaína (RGIA), tomando como base teórica o pensamento de Milton Santos quanto ao meio técnico-científico-informacional e ao uso do território. Foram realizadas incursões a campo nos municípios que vêm se consolidando na produção dessa atividade econômica na região, considerados depoimentos de sujeitos ligados às empresas e de segmentos sociais locais, registros fotográficos, levantamentos de dados secundários e elaboração de mapas, que, em conjunto, permitiram verificar a expansão e a transformação da atividade na região em referência.  Os resultados apontaram um crescimento aproximado de 300% das áreas de eucalipto entre os anos de 2010 a 2020, implicando mudanças na estrutura fundiária regional, impactos em comunidades tradicionais locais, tecnificação e racionalização da paisagem, o que permite concluir que o meio técnico-científico-informacional se expressa em uma materialidade dialética global/local, em graus de manifestação de verticalidades e horizontalidades no uso do território na área pesquisada.
Políticas de governança ambiental urbana na arena eleitoral: o caso do Rio de Janeiro nas eleições municipais de 2016
Authors: Barros Antonio Teixeira de
Published: April 2021

O artigo analisa como os 11 candidatos à eleição para a prefeitura do Rio de Janeiro em 2016 incorporaram temas ambientais em seus programas de governo, especialmente propostas de governança ambiental urbana.  O levantamento foi realizado no período de setembro a outubro de 2016, durante a campanha eleitoral. A metodologia consiste na análise dos referidos programas. De forma complementar, foram realizadas entrevistas com integrantes das equipes que gerenciaram a campanha eleitoral dos candidatos, a fim de colher subsídios para incrementar a análise qualitativa. As principais conclusões indicam que, dos 11 candidatos, oito apresentaram propostas de governança ambiental para a cidade do Rio de Janeiro. Os programas mais elaborados são de Alessandro Molon, Jandira Feghali e Marcelo Freixo. Isso se deve a três fatores: engajamento pessoal desses candidatos na construção das propostas ambientais, envolvimento com os movimentos e entidades ecológicas e a colaboração de especialistas em políticas públicas e governança ambiental.
Entraves no mercado da pesca artesanal: entre a dependência e a desconfiança
Authors: Campos Mauro Macedo , Almeida Lohana Chagas de , Timóteo Geraldo Márcio
Published: April 2021

Este artigo analisa os mercados acessados pelos pescadores artesanais das comunidades pesqueiras de Campos dos Goytacazes, região Norte do estado do Rio de Janeiro. As informações para a elaboração deste estudo foram coletadas em reuniões com os pescadores, em grupos focais e por meio de questionários aplicados de forma censitária. O levantamento dos mercados efetivos e potenciais buscou identificar as possibilidades de escoamento de pescado no município e os entraves burocráticos que limitam a constituição de novos mercados. Os resultados evidenciaram um número elevado de vendedores (os pescadores artesanais) em contraponto ao reduzido número de compradores (os atravessadores) de uma produção altamente perecível, que domina o mercado da pesca artesanal no município. A produção tem origem dispersa, em um contexto de baixa organização social e falta de confiança entre os pescadores, o que dificulta ações conjuntas em busca de novos canais de comercialização da pesca artesanal.
The Significance of Hylomorphism
Authors: De Groot Jean ,   Philosophy Documentation Center
Published: April 2021

Hylomorphism is a word for Aristotle’s belief that matter and form constitute a unity in natural things. Engaging with the work of Rémi Brague on the cosmos, I propose hylomorphism as central to the contemporary philosophy of nature that Brague seeks. Between the pre-philosophical standpoint and philosophy, there is an intermediate cognitive stage of making initial distinctions that ground philosophical truths. Philosophy of nature is the home of many of these initial distinctions. A key theme introduced in Physics 2.2 is the thinking of things in the way they are capable of existing. Analyses of Physics 2.2. and De Anima 2.3 exhibit the recognition of being as something different from the sheer existing of things. Aristotle points out mistakes in thinking about form and elucidates ontological dependencies. There are implications for the understanding of human disability.
“In As Many Ways As Something Is Predicated . . . in That Many Ways Is Something Signified to Be”
Authors: Polsky Elliot ,   Philosophy Documentation Center
Published: April 2021

Thomistic commentators agree that Thomas Aquinas at least nominally allows for “to be” (esse) to signify not only an act contrasted with essence in creatures, but also the essence itself of those creatures. Nevertheless, it is almost unheard of for any author to interpret Thomas’s use of the word “esse” as referring to essence. Against this tendency, this paper argues that Thomas’s In V Metaphysics argument that every predication signifies esse provides an important instance of Thomas using “esse” to signify essence. This reading of In V Metaphysics, which this paper defends against Gyula Klima’s alternative interpretation, suggests significant reinterpretations of Thomas’s technical terms “esse substantiale” and “esse in rerum natura” as well as Thomas’s use of “is,” both as a copula and as a principal predicate.
Diplomacia cultural socialista en la Argentina y el problema de la identidad nacional desde una perspectiva estatal. Repercusiones de la propaganda de los países socialistas en las políticas represivas locales de los años 50 (1953-1961)
Authors: Galván Maria Valéria
Published: April 2021

El presente artículo indaga en el impacto de la propaganda comunista en las políticas represivas ar-gentinas, implementadas a mediados del siglo XX. En el marco general de la diplomacia cultural de los países socialistas europeos respecto de Argentina, se analiza específicamente un tipo de propa-ganda orientada a un público reducido, formado por las comunidades de inmigrantes eslavos, con el objetivo de lograr su re-desplazamiento a territorio soviético u ocupado por regímenes comunistas en Europa del Este. Estas campañas de repatriación implementadas entre 1953 y 1961 despertaron en los sucesivos gobiernos locales preocupaciones en torno al estatus legal y a la identidad nacional de los repatriados. En respuesta a ello, el Estado argentino reforzó sus mecanismos de control y repre-sión, esbozando en estas medidas un primer concepto de “enemigo interno”.
Reakcija presadka proti gostitelju po transfuziji krvi in kako jo preprečimo
Authors: Barbarić Kovačić Aleksandra , Stanišić Slavica , Zver Samo
Published: April 2021

S transfuzijo povezana reakcija presadka proti gostitelju (angl. Transfusion associated graft versus host disease, TA-GvHD) je redek, vendar resen in življenje ogrožajoč zaplet po transfuziji krvnih pripravkov. Posledica, kolikor do nje pride, je bolnikova smrt v več kot 90 % primerov. Po transfuziji krvi se osebi z imunsko pomanjkljivostjo limfociti T iz darovalčeve krvi odzovejo na celične in tkivne antigene prejemnika krvi. Zato darovalčevi limfociti T aktivirajo in uničijo tarčne celice v tkivih prejemnika. Vzrok, da se imunske celice prejemnika ne odzovejo tako, da bi onemogočile darovalčeve limfocite T, je pomanjkljivost imunskega odziva pri prejemniku in le izjemoma vprašanje skladnosti HLA med prejemnikom in darovalcem.

Obsevanje krvnih pripravkov z ionizirajočimi žarki je najbolj učinkovita metoda za preprečevanje TA-GvHD. Patogensko inaktiviranje s psoralenom in UVA-žarki je enakovredno obsevanju, vendar se zaenkrat uporablja samo za trombocitne pripravke. Zato je pomembno, da lečeči zdravnik prepozna bolnike, pri katerih lahko nastane TA-GvHD in za njih naroča zgolj obsevane krvne pripravke. Obsevamo eritrocite, granulocite ter trombocite, kadar niso patogensko inaktivirani. Sveže zmrznjene plazme, krioprecipitata, zdravil iz krvi, kot so albumin, imunoglobulini, faktorji strjevanja krvi ... ter eritrocitov po odmrzovanju ne obsevamo, ker je vsebnost limfocitov T zanemarljiva. Priporočen osrednji obsevalni odmerek je znotraj 25–50 Gy.
EL ÁNGEL DEL NOMBRE-EL NOMBRE DEL ÁNGEL. A MODO DE PRESENTACIÓN
Authors: López Anguita Gracia
Published: April 2021

Nota editorial. Presentación del número.
LOS ROSTROS DE LOS ÁNGELES COMO ROSAS ROJAS/Rūzbehān
Authors: Crespo Ana
Published: April 2021

Resumen:El Ángel, desde su función mediadora con lo divino, se relaciona en particular con la percepción interna del color, con los bellos develamientos cromáticos del corazón (qalb). Las luces de la Inteligencia se revelan al iniciado como puntos de color rojo cornalina, antes de ello experimenta un reverdecimiento interior que indica la vida del corazón.El Ángel encarna las facultades espirituales del Hombre Perfecto, simbolizado en la figura de un Árbol y cuatro pájaros y asociados con colores. Planteamos la relación simbólica entre el Ángel y la cualidad del color, y su transcendencia para acceder al incoloro de la Luz divina. En particular abordaremos el vínculo con los colores rojo, verde y blanco.Los textos sufíes muestran una dimensión del universo angélico, referido a una cualidad interna, lúcida y visionaria de la conciencia y su relación con el color. El Ángel representa la cualidad transformadora y creadora del corazón, y es simbolizada por la rosa roja. La influencia de la literatura sufí en mi obra se refleja también en la dimensión angélica, cuya investigación planteé en diversos proyectos plásticos, desde el 92 a la actualidad y que ahora recojo una muestra en este artículo.Destacamos el episodio de la Anunciación del Ángel a María, según la descripción de Rūmī, en el que hay valiosas claves en torno a la función del artista.
Abstract:
Due to its role as a mediator with the Divine, the Angel has a special relationship with the internal perception of color, with the beautiful chromatic unveilings of the heart. The lights of Intelligence reveal themselves to the initiate as points of carnelian red, and is preceded by an inner effusion of green, which is a sign that the heart is reawakening to life.The Angel embodies the spiritual faculties of the Perfect Man, symbolized by the figure of a Tree and four birds associated with colors. We propose to establish the existence of a symbolic relationship between the Angel and the quality of color, and with its transcendence in order to attain the Divine Light, which is colorless. We will specifically address the link between red, green, and white.In Sufi texts, we find a dimension of the angelic universe referring to a lucid and visionary inner consciousness and its relationship to color. The influence of Sufi literature on my work is also reflected in the angelic dimension, which I investigated and incorporated into several plastic projects, from 1992 to the present, examples of which are found in this article.We pay particular attention to Rūmī’s account of the Annunciation of the Angel to Mary, which provides several clues that illuminate the function of the artist. This article is a summary of a longer text that will be presented shortly.
Low composite functional movement screen score associated with decline of gait stability in young adults
Authors: Lee Myeounggon , Youm Changhong , Noh Byungjoo , Park Hwayoung
Published: April 2021

Background

The functional movement screen (FMS)TM is a screening tool used to evaluate fundamental motor function. A score of 14 for the composite total FMS score (TFMS) is generally used as the cut-off point (≤14/21). In addition, gait analysis is used to evaluate fundamental motor function in humans. Thus, evaluating the fundamental motor function using the FMSTM test and gait analysis at various speeds can provide further understanding of any decline in gait stability. In this study, we aimed to investigate the association between gait ability and fundamental movement patterns in young adults according to the cut-off point.

Methods

A total of 439 participants (male: 203, female: 236) successfully completed the FMS test and a 1 min treadmill test; the participants were classified into two groups: low TFMS (≤14) and high TFMS (>14).

Results

The low TFMS group exhibited slower and shortened walking patterns and worsen gait variability than the high TFMS group. The coefficient of variance (CV) for the double support phase at a faster speed (male) and the stride length at a slower speed (female) were classifiers between the two groups. In addition, the low TFMS group demonstrated insufficient gait adaptation at the preferred and faster speeds based on the CV of the double support phase and gait asymmetry. Lower TFMS is associated with a decline in gait ability. Therefore, participants with a lower TFMS and poor gait ability may require intervention programs to prevent risk of future injury and to enhance motor function.
Universidad transdisciplinaria en el marco de la sociedad del conocimiento. Tensiones discursivas en la Universidad de Chile
Authors:   Observatorio de Innovación, Facultad de Economía y Negocios, Universidad de Chile, Henríquez Aravena Andree , Billi Marco ,   Núcleo de Estudios Sistémicos Transdisciplinarios, Facultad de Ciencias Sociales, Universidad de Chile, Faúndez Valentina ,   Núcleo de Estudios Sistémicos Transdisciplinarios, Facultad de Ciencias Sociales, Universidad de Chile, Labraña Julio ,   Núcleo de Estudios Sistémicos Transdisciplinarios, Facultad de Ciencias Sociales, Universidad de Chile, Neira Espinoza C. Ignacio ,   Núcleo de Estudios Sistémicos Transdisciplinarios, Facultad de Ciencias Sociales, Universidad de Chile, Urquiza Anahí ,   Núcleo de Estudios Sistémicos Transdisciplinarios, Facultad de Ciencias Sociales, Universidad de Chile
Published: April 2021

En el marco de las transformaciones sociales contemporáneas, y del nuevo rol adoptado por las universidades, la transdisciplina ha ido ganando un reconocimiento creciente como aproximación para comprender fenómenos que no pueden ser abordados por el modelo tradicional de especialización disciplinar, como el cambio climático, la desigualdad o, recientemente, las pandemias. Sin embargo, existe escaso estudio de experiencias específicas que ayuden a entender qué implica, qué finalidad tiene y cómo puede lograrse una mayor focalización transdisciplinaria en las universidades. Para reducir esta brecha, este artículo analiza los resultados de un diálogo participativo realizado al interior de la Universidad de Chile, examinando distintas narrativas respecto de la emergencia, oportunidades y obstáculos de la transdisciplina; los que, a su vez, dicen relación con las dinámicas históricas, organizacionales y culturales propias de la trayectoria adoptada por esta institución, y la educación superior en general, en el país: i) el compromiso social, inscrito en la tradición y misión académica de la universidad pública; ii) una promesa de novedad, innovación y transformación del quehacer científico y académico, asociada al modelo emergente de universidad emprendedora; y iii) la creciente demanda avanzada para una reforma profunda del sistema de educación superior en el país.
Directoras y directores escolares frente a la Ley de Inclusión Escolar en Chile: entre compromiso, conformismo y resistencia
Authors:   Facultad de Educación Universidad Alberto Hurtado (Chile), Rojas Fabris María Teresa , Salas Natalia , Rodríguez José Ignacio
Published: April 2021

El artículo comunica los resultados de una investigación realizada en Chile sobre las disposiciones de directoras y directores frente a la Ley de Inclusión Escolar, regulación que promueve la desegregación escolar y que comenzó en 2016. Considerando el enfoque del liderazgo inclusivo y de justicia social, el estudio se construyó a partir de una encuesta en línea a 157 directoras/es de cuatro ciudades. Dado su carácter exploratorio, se siguió un diseño cuantitativo no experimental con un alcance descriptivo. Los resultados muestran que las y los directores comparten los principios de esta política, pero prevén que tendrán problemas por la falta de capacitación de las y los profesores y por las tensiones que supone implementar políticas de inclusión en un sistema escolar que mide la calidad a partir de pruebas estandarizadas. Se propone que las y los directores manifiestan compromiso con los principios de la política, pero a la vez un conformismo y resistencia con sus implicancias más específicas, pues no aprecian que esta modifique las lógicas de funcionamiento de sus escuelas.
Efecto de la deposición de N y P atmosférico en la microfauna edáfica de sistemas de alta montaña de la red de Parques Nacionales
Authors: Sánchez Moreno Sara , Iglesias Miguel , Usero Francisco , Kindler Christian , Armas Cristina
Published: April 2021

Los impulsores de Cambio Global con mayor impacto en los ecosistemas de alta montaña son los cambios climático y de uso del suelo y la deposición de nitrógeno (N). En España, un factor adicional es la deposición de fósforo (P) proveniente del polvo sahariano. La deposición atmosférica de N y P puede tener un gran impacto en el ciclado de nutrientes y en la biota edáfica. Durante tres años hemos simulado deposición atmosférica de N y P en cuatro ecosistemas alpinos de la red de Parques Nacionales siguiendo un gradiente latitudinal de aridez y analizado sus efectos sobre las comunidades de nematodos, hongos y bacterias. La microbiota redujo su presencia con la aridez, pero solo los hongos respondieron a la deposición de N. La abundancia de nematodos también disminuyó con la aridez, y, mientras que la deposición de N aumentó su biomasa debido al incremento de la abundancia de nematodos bacterívoros, el P incrementó la contribución porcentual de bacterívoros y fungívoros simplificando las redes tróficas edáficas. Los nematodos fungívoros fueron más sensibles que los bacterívoros a los desbalances estequiométricos y, en general, las comunidades de sistemas áridos se caracterizaron por una prevalencia del canal bacterívoro de descomposición de la materia orgánica y una menor importancia de la herbivoría subterránea. El incremento de la aridez, la deposición de N atmosférico y potencial aumento de la deposición de P sahariano podrían tener efectos a largo plazo en la composición y funciones ecosistémicas de las redes tróficas edáficas de alta montaña.
Cambio climático y variación de los ciclos vitales con la altitud
Authors: Obeso José Ramón , Laiolo Paola
Published: April 2021

El cambio climático es un factor clave de pérdida de diversidad, está modificando el área de distribución de las especies y sus interacciones, y también los rasgos de sus ciclos vitales. En este trabajo se sintetiza la información disponible sobre las modificaciones de los ciclos vitales conocidas o previstas considerando los efectos de los gradientes de altitud en los sistemas montañosos. Se enmarca en la hipótesis del continuo rápido-lento y considera como variables clave la edad de la primera reproducción, la inversión en reproducción y la duración del ciclo. Se ha documentado, con carácter general, que especies de diferentes grupos taxonómicos tienen ciclos vitales más rápidos a menor altitud (mayores temperaturas). Contrariamente, en las zonas de mayor altitud el tiempo hasta la maduración se alarga, la inversión en la reproducción es proporcionalmente menor y la esperanza de vida y longevidad aumentan. Se documentan en esta revisión algunos ejemplos en los que los ciclos vitales varían con la altitud y estas variaciones se deben, con frecuencia, a adaptaciones locales. Además, se presenta un caso de estudio en el que las especies de aves que conforman una comunidad tienden a converger a lo largo de un gradiente de altitud hacia ciclos vitales más lentos a mayor altitud. Tanto en el caso intraespecífico, como en el interespecífico, es previsible que el cambio climático esté modificando las características de los ciclos vitales acelerándolos de acuerdo con la actual situación a menores altitudes.
ClimaNevada: Base de datos climática del Observatorio de Cambio Global de Sierra Nevada
Authors: Pérez-Luque Antonio Jesus , Peinó-Calero Eric , Rodríguez-Brito Alicia , Esteban-Parra Maria Jesús , Merino-Ceballos Manuel , Guerrero-Alonso Pablo David , Moreno-Llorca Ricardo , Ros-Candeira Andrea , Zamora Regino
Published: April 2021

Disponer de una buena caracterización climática es un aspecto clave para el seguimiento de los efectos del cambio global sobre todo en ambientes de montaña. Sin embargo, los datos climáticos de muchas de las zonas de montaña proceden de fuentes muy heterogéneas y muy dispersas, lo que hace que el acceso y la descarga de esos datos sean tareas que se tornan a menudo arduas y tediosas. En este trabajo presentamos ClimaNevada, una base de datos robusta sobre información climática en Sierra Nevada, que armoniza, documenta e integra datos climáticos procedentes de estaciones meteorológicas y de sensores. Hemos desarrollado una plataforma que aglutina toda la información y permite la descarga de datos de una forma sencilla y siguiendo la filosofía Open Access. Asimismo, presentamos un caso de estudio en el que se generan series de datos homogéneos a partir de ClimaNevada, para la evaluación de tendencias temporales de la precipitación en Sierra Nevada.
Áreas marginales en ecosistemas alpinos: definición y valor evolutivo en un contexto de cambio climático
Authors: Morente Javier , Lara Romero Carlos , García Fernandez Alfredo , Rubio Teso María Luisa , Prieto-Benítez Samuel , Iriondo José María
Published: April 2021

En el contexto de cambio climático en el que nos encontramos, cada vez más poblaciones se ven sometidas a presiones selectivas extremas definitorias de una marginalidad ambiental. Determinar el valor evolutivo y el potencial adaptativo de las poblaciones marginales sigue siendo un reto de enorme importancia actualmente y tiene implicaciones directas sobre la conservación de la biodiversidad. Para afrontar este reto conviene considerar de manera integradora los principales factores que influyen en los procesos de adaptación evolutiva (diversidad genética, presiones selectivas y flujo genético). En este trabajo presentamos una hoja de ruta que parte de la definición del concepto de marginalidad ambiental a la integración de experimentos de campo y laboratorio, incluyendo la utilización de modelos de nicho ecológico, estudios genéticos y genómicos, experimentos de jardín común in situ y ex situ, simulaciones de flujo genético y siembras recíprocas, con el fin de determinar el potencial evolutivo que reside en poblaciones que habitan áreas ambientalmente marginales y, por tanto, también su valor de conservación. Para ello utilizamos como caso de estudio la investigación llevada a cabo con Silene ciliata en las poblaciones del Sistema Central. Nuestros estudios indican que algunas de las poblaciones que habitan en áreas marginales mantienen niveles considerables de diversidad genética y presentan claras evidencias de adaptación local. En consecuencia, estos resultados destacan el relevante valor de conservación que pueden tener las poblaciones marginales, especialmente en un contexto de cambio climático.
Calentamiento global y sus efectos en plantas de alta-montaña en Chile central: una revisión
Authors: Cavieres Lohengrin , Valencia Graciela , Hernández Fuentes Carolina
Published: April 2021

Los ecosistemas de alta montaña se caracterizan por condiciones climáticas rigurosas como bajas temperaturas, fuertes vientos y sustratos inestables. Por ello se les considera centinelas del cambio climático global. Muchos estudios se han desarrollado en diversas montañas del hemisferio norte donde, producto del cambio climático global, se han observado cambios en la distribución altitudinal de las especies, aumentos en la riqueza de especies, y una serie de efectos en distintos estados del ciclo de vida de las plantas (germinación, crecimiento, reproducción, etc.). Sin embargo, hay pocos estudios sobre el efecto en el reclutamiento de plántulas y la tasa de fotosíntesis de individuos. En esta revisión recopilamos los resultados que se han obtenido en estudios sobre el impacto del calentamiento sobre estos procesos en plantas de la zona de alta montaña de los Andes de Chile central. A diferencia de otras montañas, al estar ubicada en una zona con clima tipo mediterráneo, los veranos son secos lo que genera que las elevaciones bajas son cálidas y secas, y las altitudes mayores son frías y húmedas. Esto hace que a baja altitud los efectos del calentamiento sean por lo general perjudiciales sobre la supervivencia de plántulas y el proceso de fotosíntesis, ya que mayores temperaturas exacerban la sequía que caracteriza estas altitudes. En cambio, en altitudes mayores el aumento de la temperatura tiene efectos positivos sobre dichos procesos, aunque las respuestas son muy especie-especificas.
The Impact of Foreign Aid on Economic Growth in Palestine: An Empirical Evidence
Authors: Badwan Nemer , Atta Mohammed
Published: April 2021

This study examines the Impact of Foreign Aid on Economic Growth in Palestine by considering time series data of the last twenty years from (2000-2019). Foreign Aid's Impact on the Palestinian Economy explored with the Gross Domestic Product (GDP) as the dependent variable against few selected independent variables such as Foreign Aid, Remittance, Investment, Labour Force and Lagged (GDP). This study used the Partial Adjustment Model to analyze the Impact of Foreign Aid on Economic Growth in Palestine and also applied the (Chow Test) to examine whether there was a Structural Breakthrough in the Palestinian Economy. The results indicate that Foreign Aid has a positive relationship with (GDP). However, the relationship is not significant since the higher volume of Foreign Aid used in Humanitarian and Social Welfare rather than Production Activities in the real sectors. (Chow Test) shows that the relationship between Foreign Aid (GDP) has not witnessed a Structural Breakthrough in the Palestinian Economy over the past twenty years. In light of these empirical results, we suggest that Government Policy-Makers and Decision-Makers allocate this Foreign Aid to Productive Sectors and Human Capital formation (HC) activities with a special focus on capital expenditures to achieve a high rate of the country's Economic Growth and Development and to meet the periodic plan and Long-Term Development goals.
Alcohol Related Facial Injuries
Authors: Arthur Nwashindi , Dim E. M.
Published: April 2021

Aim: Consumption of alcohol plays a key role in traumatic injuries The capacity of alcohol to distort human cognitive ability and reasoning makes it an important factor in the causation of motor vehicle and interpersonal violence-related injuries The aim of this study was to investigate the role of alcohol in severe facial injuries in settings of motor vehicular crashes and interpersonal violence.

Study Design: A prospective study of 118 patients who suffered alcohol-related facial injuries.

Place and Duration of Study: The study was conducted at the University of Uyo teaching hospital Uyo, Nigeria over a 5-year period, from January 2007 to January 2021.

Methodology: The variables analyzed included socio demographics, nature of injury and sites of injuries. Alcohol Use Disturbance Identification Test (AUDIT test) was used to identify risks and damages of alcohol use and dependence. Data analysis was done using SPSS version 21.0. Multivariate analysis was carried out using binary logistic regression analysis, P = 0.05 was considered to be statistically significant.

Results: A total of 118 patients suffered alcohol-related facial injuries in the period of the study. There were 97 males and 21 females, giving a male to female ratio of 4:1 The mean age  of the patients’ population was  43 .The commonest age range involved in alcohol-related facial injuries was 29-38 years. Road traffic injuries were the commonest cause of facial injuries.  Medium risk alcohol consumption and male gender were identified as risk factors for  moderate and severe injuries  as well as for avulsive injuries.

Conclusion: Alcohol-related injuries often turn out severe, and the identifiable risk factors include male gender, high-risk alcohol consumption and road traffic crashes.
On the Irrationality and Transcendence of Rational Powers of e
Authors: Ghosh Sourangshu
Published: April 2021

A number that can’t be expressed as the ratio of two integers is called an irrational number. Euler and Lambert were the first mathematicians to prove the irrationality and transcendence of e. Since then there have been many other proofs of irrationality and transcendence of e and generalizations of that proof to rational powers of e. In this article we review various proofs of irrationality and transcendence of rational powers of e founded by mathematicians over the time.
Investigation of the Adsorption Potentials of an Organic Adsorbent for Phenol Removal from Aqueous Solution
Authors: Muko-Okoro C.E. , Obiora-Okafo I.A. , Ndive J.N.
Published: April 2021

Phenol is a prevalent pollutant found in many industrial wastewaters, and it is paid singular attention because of its special features including high toxicity, carcinogenic properties, and vital cumulative ability that affects the health of humans and the environment. The current study investigated the removal of phenol from synthetic aqueous solutions using prepared Moringaoleifera seed shell as an adsorbent. The efficiency of phenol removal by Moringaoleifera seed shell was evaluated in a batch system, and different parameters such as initial concentration of phenol (100, 200, 300, 400 and 500 mg/L), contact time (10, 20, 30, 40, 50 and 60 min), and adsorbent dosage (0.2, 0.4, 0.6, 0.8, and 1.0 g) were studied. The results showed that the highest percentage of phenol removal by the ash occurred at 0.8 g dosage, contact time of 40 min, and initial concentration of 500 mg/L giving 87.2% phenol removal. The adsorption process was modeled with Langmuir and Freundlich isotherms and adsorption kinetics (pseudo-first order and pseudo-second order) at controlled temperatures. The results showed that the experimental data fitted the Langmuir (R2 = 0.8338) much better than the Freundlich model (R2 = 0.7314). For the analysis of the adsorption kinetics, the results showed that the experimental data fitted the pseudo-second order kinetics (R2 = 0.999) much better than the pseudo-first order kinetics (R2 = 0.5042). In general, the results of this study revealed that Moringaoleifera seed shell has suitable potential for use in removing phenol from aqueous solution on operation and practical scales due to its availability and organic nature.
A Comprehensive Review and Perspective of Herbal Medicines in the Treatment of COVID-19
Authors: Moin Afrasim , Meenakshi S. , Rizvi Syed Mohd Danish , Nandini Nanhi , Hussain Talib , Hussain Arshad , Meghana G. S. , Manohar M. , Sathishbabu P. , Gowda D. V.
Published: April 2021

Background: An emergent COVID-19 outbreak originated in Wuhan City, in December 2019. The COVID-19 contamination has swiftly unfold from Wuhan to maximum different provinces and different 24 countries. WHO declared a public health emergency of global concern over this worldwide COVID-19 outbreak on 30th January 2020. Manifold research has been intensely initiated for immunization and drug development for COVID-19 till date no specific vaccine or approved drugs are accessible for COVID-19. Alternatively, therapy consists of supportive care and non-specific anti-viral, anti-malarial, and antibiotics are being testedas drugs for COVID-19. Though, novel approaches could play a crucial role to combat mortality rate and patient recovery in the treatment of COVID-19.

Objective: To reveal the epidemiology, pathophysiology, and comparison of promising synthetic and natural drug targets to avert and cure of COVID-19.

Method: This article sets a brief understanding of the viral characteristics, its life cycle, infection to humans, and the pathophysiology of the disease. It also throws light on the currently used synthetic medicines. we have reviewed the effect of natural products to prevent or treat COVID-19 infection. Their mechanisms of action have been elaborately discussed. literature research was undertaken using PubMed, Google Scholar, Scopus, and WHO website. The different herbal products (extracts) and their moieties which are promising as anti-SARS-CoV-2 by direct inhibition of the virus replication or entry has also been discussed.

Results and Conclusion: In conclusion we have highlighted that natural therapeutics either alone or in combinationcould be used as alternative medicines to treat/prevent COVID-19 infection. Moreover, their structures may offer clues for the development of anti-SARS-CoV-2 drugs.The integration of nanocarriers for effectively delivering the conventional as well as the herbal drugs becomes a key point for their efficacy and safety.
Impact of the Emerging COVID-19 Pandemic on the Consumption of Multivitamins (C, D and Zinc) by the Saudi Arabian Population
Authors: Bakhshwin Duaa Mohamed , Bakhshwin Abdulaziz
Published: April 2021

Background: On March 11, 2020, the World Health Organization (WHO) announced the Coronavirus outbreak officially as a pandemic. This pandemic has led to new measurements to prevent viral spread. The measures included decreasing the person’s mobility outside homes with subsequent changes in the lifestyles, particularly in physical activity and eating habits. It has been noticed that consumption of some vitamins may help in preventing or reducing the symptoms of viral infection. Those vitamins include vitamin C, D and zinc. There is a common observation that the general public believes that the use of vitamins, especially vitamins C, D and zinc, reduces the chance of acquiring COVID-19.

Objectives: The aim of this study was to determine the impact of COVID-19 pandemic on taking vitamins supplements by the Saudi general population in order to explore their believes regarding the protective value of these vitamins against COVID-19 infection.

Subjects and Methods: This cross-sectional study was conducted using a self-administrated questionnaire that was designed, uploaded to the Google form and distributed online to the general Saudi population through the social media (Whatsapp, Twitter) as well as through email between August and December 2020. Statistical Packaged of Social Sciences program (SPSS) for Windows (version 17.0., Chicago: SPSS Inc) was used to analyze the data. A significant difference was considered when the p value is < 0.05. Student t-test and Chi-square (χ2) test were used to compare the studied variables as appropriate.

Results: A total of 1043 participants were included in this study (64.9% females, 35.1% males). The mean age for them was 35.3±14.78 years. Only 9.3% (97 participants) were diagnosed to have COVID-19. About 28% of the participants were in contact with COVID-19 cases. Among participants diagnosed to have COVID-19 infection, (13% versus 29%) were taking vitamin C and (2% versus 15%) were taking zinc supplements daily during the 6 months before and after the pandemic, respectively, while (20% versus 25%) were taking vitamin D supplements weekly during the 6 months before and after the pandemic, respectively. Among participants who were in contact with COVID-19 cases, (8% versus 20%) and (3% versus 11%) were taking vitamin C and zinc supplements daily during the 6 months before and after the pandemic, respectively, while (14% versus 16%) were taking vitamin D supplements weekly during the 6 months before and after the pandemic

Conclusion: The interest of taking multivitamin by Saudi population, such as vitamins C and D, zinc increased during and after the pandemic compared to that before it. There is no scientific evidence based on previous studies confirmed the role of dietary supplementation and multivitamins in preventing COVID-19 infection, therefore, effective education on the rationale use of vitamins during COVID-19 pandemic should be emphasized at local and/or national levels.
Facile Green Synthesis of Iron Oxide Nanoparticles Using Phoenix dactylifera L. Seed Extract and Their Antibacterial Applications
Authors: Majid Abdul , Naz Farah , Jamro Hatim Ali , Ansari Bilal , Abbasi Sanaullah , Lal Sham , Ujjan Safdar Ali
Published: April 2021

Aim: The synthesis methods of iron oxide nanoparticles (IONPs) have got great attention in recent years, due to their variety in physicochemical properties and applications. This study aimed for the green synthesis of the IONPs using an aqueous extract of P. dactylifera L. seeds for its antibacterial applications.

Methodology: IONPs were prepared in an aqueous seed extract of P. dactylifera L. The physicochemical characterisations were performed with transmission electron microscopy (TEM) to study the shape of obtained nanoparticle, energy-dispersive spectroscopy (EDS) for elemental confirmation of iron and oxygen, dynamic light scattering (DLS) for particles size measurement, vibrating sample magnetometer (VSM) for saturation magnetisation, Infrared spectroscopy (FTIR) for chemical confirmation of function groups and X-ray diffraction (XRD) for crystalline nature. The polyphenols contents were also determined; we suggest that the presence of phenolic compounds is the key element involved in the formation and the stabilisation of IONPs. Antibacterial activity was determined using disc diffusion assay and minimum inhibitory concentration (MIC) of the IONPs were determined by broth dilution assay.

Results: The biosynthesised IONPs showed crystalline magnetite spherical morphologies with average diameter 30 nm. Discs with all the concentrations of IONPs tested in this study (10 - 100 ug.mL-1) showed antibacterial activity against bacterial strains tested (Staphylococcus epidermidis, Klebsiella pneumoniae and Pseudomonas aeruginosa). MIC values were found to be 30 ug.mL-1, 50 ug.mL-1 and 60 ug.mL-1 for S. epidermidis, K. pneumoniae and P. aeruginosa respectively.

Conclusion: The biosynthesis of IONPs has provided, reliable, safe, simple and eco-friendly method. Hence, this study has focused on biological method of synthesis of IONPs. The IONPs synthesized in this study can be used as the therapeutic agents against bacteria.