bluuebunny/crossref_metadata_2025 huggingface dataset:
ESTUDIO DE LA OFERTA DE PRECIOS HOTELEROS ANTICIPADA A TRAVÉS DE UN IMPORTANTE CANAL DE DISTRIBUCIÓN ONLINE
Authors: Sánchez-Lozano Gloria , Nobre Pereira Luis , Chávez-Miranda Esther
Published: January 2021

Este trabajo se centra en el estudio de la oferta de precios a través de canales online (Booking.com) en un destino turístico. Los hoteles se han seleccionado mediante muestreo aleatorio simple estratificado con afijación proporcional. Se trabaja con un conjunto de datos de grandes dimensiones (big data, con un total de 1.353.751 registros). Se considera una antelación de estancia de aproximadamente un año, lo que supone una gran novedad respecto a estudios previos. En el trabajo se presentan los valores de precios considerando los datos habitualmente publicados por los hoteles en estos canales, lo que permite ofrecer una panorámica de la operativa relativa a la oferta de precios a través de la distribución online a nivel de destino turístico.

This work focuses on the study of prices offered through an online distribution channel (Booking.com) on a concrete tourism destination. Hotels were selected by a stratified simple random sampling method with proportional allocation. Research is done over an extensive dataset (1,353,751 of records, big data). The advance booking period considered covers approximately a whole year, and this represents a great novelty with respect to previous studies. Average prices are calculated from the values ordinarily published by hotels on this type of channels, which allows providing the outline of the operational management of prices implemented on the destination, through the online distribution and from the supply perspective.
LA MUJER EMPRENDEDORA EN EL TURISMO RURAL: PECULIARIDADES DEL CASO COSTARRICENSE A TRAVÉS DE LA REVISIÓN BIBLIOGRÁFICA
Authors: Gutiérrez Cruz Merlyn , Such Devesa María Jesús , Gabaldón Quiñones Patricia
Published: January 2021

Este artículo analiza el fenómeno de la mujer emprendedora en el turismo rural en Costa Rica, enmarcándola en el contexto latinoamericano y en el de las emprendedoras rurales. A partir de una revisión sistemática de la literatura, se define el perfil de las empresarias, sus motivaciones y las barreras que enfrentan. Los resultados ponen de manifiesto las importantes similitudes entre las emprendedoras turísticas rurales costarricenses con el resto de las emprendedoras en Latinoamérica y del mundo. Este estudio contribuye al conocimiento de las emprendedoras dentro del marco del turismo rural, esencial para el desarrollo económico del país.

This article analyzes the phenomenon of entrepreneurial women in rural tourism in Costa Rica, framed within the Latin-American and rural entrepreneurship context. Using a systematic literature review, the profile of business-women gets defined through their motivations to start their businesses and the barriers they face. The results show the important similarities between Costa Rican rural tourism entrepreneurs and other female entrepreneurs in Latin America and the world. This study contributes to the knowledge of these entrepreneurs within the framework of rural tourism, essential for the economic development of developing countries.
EL TURISMO MARINERO COMO OPCIÓN DE DESARROLLO LOCAL SOSTENIBLE A PARTIR DEL EMPODERAMIENTO FEMENINO
Authors: Caamaño-Franco Iria , Andrade Suárez María , Pérez-García Antonia
Published: January 2021

El turismo marinero se ha convertido en un referente turístico con más de dos décadas de expansión a nivel internacional y en continuo crecimiento. En este contexto, el presente trabajo tiene como objetivo estudiar el turismo marinero como opción de desarrollo local sostenible a través del empoderamiento femenino. El estudio se ha basado en entrevistas semiestructuradas a mujeres que lideran proyectos de turismo marinero en Galicia y en un análisis de contenido de las noticias sobre el tratamiento que la prensa les otorga. Los resultados evidencian que la mayor parte de los proyectos tienen un carácter innovador, diversificado, participativo y responsable. Se constata que, a pesar del evidente avance, es necesario promover más la iniciativa empresarial femenina en el ámbito del turismo marinero, además de fomentar su presencia y proyección social a través de los medios. 

Marine tourism has become a tourist reference with more than two decades of international expansion and continuous growth. In this context, the present work aims to study marine tourism as an option for sustainable local development through female empowerment. The study has been based on semi-structured interviews with women who lead marine tourism projects in Galicia and on a content analysis of the news on the treatment that the press gives them. The results show that most of the projects are innovative, diversified, participatory and responsible. It is found that, despite the evident progress, it is necessary to further promote female entrepreneurship in the field of marine tourism, in addition to promoting their presence and social projection through the media.
EVOLUCIÓN Y ANÁLISIS BIBLIOMÉTRICO DE LA REVISTA CUADERNOS DE TURISMO (1998-2019)
Authors: Corral-Marfil José-Antonio , Espejo Marín Cayetano
Published: January 2021

Los objetivos son analizar los artículos publicados en Cuadernos de Turismo y valorar la evolución de la revista. Se estudian los hitos históricos, la distribución de frecuencias de los artículos y las autorías, el origen geográfico e institucional de las autorías, las temáticas y los territorios investigados, el impacto científico, el origen de las citas recibidas y el destino de las citas emitidas. A pesar de la concentración de autorías de España, la revista ha ganado influencia en Iberoamérica. Las temáticas están globalmente en sintonía con la investigación turística internacional. Entre las causas del creciente impacto de la revista, se encuentra la adaptación a los notables cambios que se han producido durante las dos últimas décadas en el entorno de las publicaciones académicas.

The objectives are to analyse the articles published in Cuadernos de Turismo and to assess the journal's evolution. The historical milestones, the frequency distribution of articles and authorships, the geographical and institutional origin of authorships, the subjects and territories researched, the scientific impact, and the main cited and citing publications are studied. Despite the concentration of authorships from Spain, the journal has progressively gained influence in Latin America. The subjects are globally consistent with the international tourism research. Among the causes of the journal’s growing impact, there is the adaption to the remarkable changes that have occurred in the environment of the academic publishing during the last two decades.
Moral, isolation, diakoni, tilblivelse og fortvivlelse – i vidt forskellige teologiske sammenhænge
Authors: Nielsen Jesper Tang
Published: January 2021

Årets årgang af Dansk Teologisk Tidsskrift består af to dobbeltnumre. Med dette bind foreligger det første. Det er i sagens natur mere omfattende end normalt. Næste dobbeltnummer følger inden for overskuelig tid. Ud over den utraditionelle nummering følger Dansk Teologiske Tidsskrift sin traditionelle redaktionelle stil. Vi bringer fem artikler, der dækker alle teologiens discipliner og behandler såvel nye teologiske spørgsmål som gamle spørgsmål på en ny måde.

Første artikel af Jan Dietrich omhandler moralsk realisme i Det Gamle Testamente eller den Hebraiske Bibel, som man rettelig bør sige, når man ikke ønsker at anvende det kristne perspektiv på denne skriftsamling. Dietrich tager udgangspunkt hos Platon og stiller spørgsmålet, om det gode er godt i sig selv; eller det er godt, fordi Gud siger, at det er godt? Hvordan forholder Gud sig til det i den første del af Bibelen?Efter eksegesen kommer kirkehistorien. Mette Birkedal Bruun præsenterer sin store disputats om Armand-Jean Rancé og hans reform af cistercienserklosteret La Trappe. Rancés asketiske program indebar en isolation fra samfundet, men samtidig foregik en ret intens udveksling med den omgivende verden. Det dynamiske forhold mellem tilbagetrækning og engagement er temaet for hendes undersøgelse.I den næste artikel præsenteres diakonien som et nyt fagområde inden for dansk teologi. Med anledning i kandidatuddannelsen i diakonived Aarhus Universitet præsenterer Jakob Egeris Thorsen det faglige felt både nationalt og internationalt.De to sidste bidrag omhandler på forskellig vis Søren Kierkegaard. Det første af Anne Louise Nielsen afdækker en teologi hos Kierkegaard. Det er et gammelt spørgsmål, om Kierkegaard overhovedet kan siges at have fremlagt en teologi. Artiklen argumenterer for, at der faktisk foreligger en teologi i Filosofiske Smuler, som kan karakteriseres som en tilblivelsens teologi. Den sætter forfatteren i relation til nyere teologiske positioner.Den sidste artikel læser Lykke-Per på baggrund af Søren Kierkegaards Sygdommen til Døden. Dermed afdækkes, at Henrik Pontoppidanhar været langt mere influeret af Søren Kierkegaards tanker, end man ellers har været opmærksom på. Romanens hovedperson, Per Sidenius, er visse steder fortvivlet på en måde, som bedst forstås gennem Kierkegaards definitioner.Til dette nummer er der god grund til at ønske god læselyst.
Den samskabende kirke?
Authors: Viftrup Lars Buch
Published: January 2021

Co-production has become an important notion within public governance, particularly in municipalities. The Danish Folk Church has a long history of working together with the municipalities and is an institution with many civil resources. Through an empirical study involving the municipality, the church and citizens of Aarhus, this article discusses the implications of co-production for the church and its theology. St. Augustine’s concepts of the “City of God”, Luther’s concept of the “priesthood of all believers” and “vocation” and Luhmann’s concept of faith as dealing with “paradox” offer an analytical frame for understanding how the church co-produces the city. The “priesthood of all believers” underlines the “bottom up” character of the congregation and thereby its civil character, while the “City of God” as an ambivalent and paradoxical term for salvation holds together the tensions involved in co-production.
Perceptions des pratiques en matière d’audition de suspects
Authors: Noc1 Mathilde , Ginet Magali
Published: January 2021

Le principal objectif de cette étude était d’évaluer les perceptions d’agents des
douanes françaises en matière d’audition de suspects. Étant donné le peu de formation
théorique existant en France, il était attendu que ces agents déclarent utiliser des
méthodes considérées comme néfastes, dans la littérature scientifique, pour le déroulement
et l’efficacité de la conduite d’auditions. Soixante-quatorze agents des douanes ont répondu
à un questionnaire les invitant à évaluer l’usage, dans leur pratique, de méthodes
d’audition de suspects, certaines étant considérées comme bénéfiques et d’autres, néfastes.
Conformément à nos attentes, les résultats ont indiqué que les agents des douanes
déclaraient utiliser certaines méthodes bénéfiques pour le déroulement de l’audition, mais
aussi néfastes, telles que l’usage privilégié d’un questionnement fermé, la maximisation, la
pression, etc. Les niveaux d’expérience et de présomption de culpabilité avaient également
un impact sur les méthodes utilisées. L’analyse du questionnement a permis de montrer que
les questions dirigées étaient largement utilisées. Des préconisations en termes de
formation professionnelle sont formulées.
¡Más chutes no! La heroína, entre arma de la democracia y vehículo heroico.
Authors: Orihuela Antonio
Published: January 2021

La contracultura española floreció en el paréntesis de permisividad que el proceso transicional, desde las opresivas estructuras franquistas a la democracia, dejó  expedito a los experimentos sociales y culturales. A partir de 1978, el Estado reaccionará a toda esta floración sociocultural de signo autónomo, fomentando un clima de truculencia, sensacionalismo, miedo, paranoia, delincuencia, estigmatización de la pobreza y drogas que, orquestado desde los media, sorprendentemente, fueron también asumidos como rasgos identitarios por los mismos  grupos marginalizados.
'El sofista negro. Muhammad Ali, orador y púgil', de Marco Mazzeo
Authors: Jossa Emanuela
Published: January 2021

Reseña de Mazzeo, Marco (2020). El sofista negro. Muhammad Ali, orador y púgil, Barcelona, Tercero Incluido Italian Radical Thought, Muhammad Ali, Marco Mazzeo
Reajustes de la violencia en una novela, su adaptación al cine y un remake: 'El secreto de sus ojos'
Authors: Malpartida Tirado Rafael
Published: January 2021

En este trabajo se propone atender a un aspecto poco transitado en los estudios sobre transtextualidad: el tránsito de un texto literario a uno fílmico (El secreto de sus ojos) y la relación que establecen con un remake (El secreto de una obsesión), adoptando una tipología que contempla las categorías de la readaptación, el remake simple y la adaptación compuesta o mixta. Se incide para ello en la representación de la violencia, de acuerdo con la distinción postulada por Steven Pinker (que sigue a Thomas Hobbes) sobre las causas del conflicto humano, y se considera, por una parte, la construcción de los personajes, y por otra, la forma en que se muestran las imágenes. De este modo, se analizan los necesarios reajustes que se llevan a cabo en dos contextos muy distintos: la etapa previa a la Dictadura Militar Argentina de 1976 (término en el que se mueven de forma variable la novela de Sacheri de 2005 y la película de Campanella de 2009) y la hipervigilancia antiterrorista tras los atentados del 11-S (en la versión de Billy Ray de 2015).
'La Desaparición de los Rituales. Una topología del presente', de Byul-Chung Han
Authors: Gonzalez Jorge
Published: January 2021

Reseña de 'La Desaparición de los Rituales. Una topología del presente', de Byul-Chung Han
'La memoria de los otros. Relatos y resignificaciones de la transición española en la novela actual', de Violeta Ros Ferrer'
Authors: Mira Alepuz Eva
Published: January 2021

Reseña de 'La memoria de los otros. Relatos y resignificaciones de la transición española en la novela actual', de Violeta Ros Ferrer'
Resistir a les palpentes / Resistir a tientas
Authors: García del Río Antonio
Published: January 2021

Libro de poemas de Antonio García del Río.
Traducción al castellano de Martina Pérez, Núria Lorente y Pau Pertegaz.
Maquetación de Nuria Bartual.
Cuaderno de voces para Tony
Authors: Colectiva Autoría
Published: January 2021

Cuaderno de voces. Reúne textos de amigxs, familiares y colegas de Tony García del Río.
Arrangement of projection angles in Mojette-transform based tomography
Authors: Wu Shen-Jiang , Liu Rong-Ming , Wang Jia , Li Dang-Juan , Cheng Jun-Xia ,   School of Optoelectronic Engineering, Xi’an Technological University, Xi’an 710021, China
Published: January 2021

Computed tomography (CT) is an effective tool for three-dimensional (3D) imaging by using optical detectors to capture the two-dimensional (2D) projections of tested parameters from multiple views and realizing 3D reconstruction through various algorithms. However, for practical applications, typically only a few detectors can be applied due to their high expense and the limited optical access of the test environment. The realization of high precision reconstruction with a few projections is of great significance for promoting the development and application of CT technology. The spatial arrangement of the detectors determines the amount of useful information collected by the system, which greatly affects the quality of CT reconstruction. Therefore, in this work we study the optimization method of projection arrangement based on the 3D Mojette transform theory.

Mojette transform is a special discrete form of Radon transform, which can realize projection sampling with minimum redundancy and accurate tomographic reconstruction from less projection angles. It provides a new way to realize the CT technology with fewer projections. However, the existing researches mainly focus on the reconstruction theories of 2D Mojette transform, which is used for realizing the 2D slice tomography. In order to realize the real 3D tomographic reconstruction, in this work we establish a mathematical model of 3D Mojette transform, and study its accurate reconstruction condition. The results show that the 3D Mojette transform is a combination of twice 2D Mojette transform in two directions. The accurate reconstruction condition of 3D Mojette transform is that the sum of the absolute values of projection vectors’ components in x, y, and z directions is greater than the number of discrete grids in each direction. The correctness of the mathematical model and the accurate reconstruction condition are verified by numerical simulations.

Considering the limitation of the pixels in the practical detectors, the method to determine the optimal arrangement of projection angles is proposed. The results indicate that the optimal arrangement is that all detectors are located in the same horizontal plane around the tested object, where the projection model is reduced to 2D Mojette transform. In this case, the minimum projection angles and pixels are required and the projection angles can be positioned in a smaller spatial range. If the condition cannot be satisfied in practice, projection vectors with smaller |pi| and |qi| should be chosen. This research provides the theoretical basis for establishing the actual CT system.
Behavioral role of PACAP signaling reflects its selective distribution in glutamatergic and GABAergic neuronal subpopulations
Authors: Zhang Limei , Hernandez Vito S , Gerfen Charles R , Jiang Sunny Z , Zavala Lilian , Barrio Rafael A , Eiden Lee E
Published: January 2021

The neuropeptide PACAP, acting as a co-transmitter, increases neuronal excitability, which may enhance anxiety and arousal associated with threat conveyed by multiple sensory modalities. The distribution of neurons expressing PACAP and its receptor, PAC1, throughout the mouse nervous system was determined, in register with expression of glutamatergic and GABAergic neuronal markers, to develop a coherent chemoanatomical picture of PACAP role in brain motor responses to sensory input. A circuit role for PACAP was tested by observing Fos activation of brain neurons after olfactory threat cue in wild-type and PACAP knockout mice. Neuronal activation and behavioral response, were blunted in PACAP knock-out mice, accompanied by sharply downregulated vesicular transporter expression in both GABAergic and glutamatergic neurons expressing PACAP and its receptor. This report signals a new perspective on the role of neuropeptide signaling in supporting excitatory and inhibitory neurotransmission in the nervous system within functionally coherent polysynaptic circuits.
Phenotypic and molecular evolution across 10,000 generations in laboratory budding yeast populations
Authors: Johnson Milo S , Gopalakrishnan Shreyas , Goyal Juhee , Dillingham Megan E , Bakerlee Christopher W , Humphrey Parris T , Jagdish Tanush , Jerison Elizabeth R , Kosheleva Katya , Lawrence Katherine R , Min Jiseon , Moulana Alief , Phillips Angela M , Piper Julia C , Purkanti Ramya , Rego-Costa Artur , McDonald Michael J , Nguyen Ba Alex N , Desai Michael M
Published: January 2021

Laboratory experimental evolution provides a window into the details of the evolutionary process. To investigate the consequences of long-term adaptation, we evolved 205 Saccharomyces cerevisiae populations (124 haploid and 81 diploid) for ~10,000 generations in three environments. We measured the dynamics of fitness changes over time, finding repeatable patterns of declining adaptability. Sequencing revealed that this phenotypic adaptation is coupled with a steady accumulation of mutations, widespread genetic parallelism, and historical contingency. In contrast to long-term evolution in E. coli, we do not observe long-term coexistence or populations with highly elevated mutation rates. We find that evolution in diploid populations involves both fixation of heterozygous mutations and frequent loss-of-heterozygosity events. Together, these results help distinguish aspects of evolutionary dynamics that are likely to be general features of adaptation across many systems from those that are specific to individual organisms and environmental conditions.
Genome-wide identification, evolution, expression, and alternative splicing profiles of peroxiredoxin genes in cotton
Authors: Feng Yulong , Wei Renhui , Liu Aiying , Fan Senmiao , Che JinCan , Zhang Zhen , Tian Baoming , Yuan Youlu , Shi Gongyao , Shang Haihong
Published: January 2021

Peroxiredoxin (PRX) is a ubiquitous thioredoxin-dependent peroxidase that can eliminate excessive free radicals produced by stress and protect cells from oxidative damage. PRXs are also involved in reactive oxygen species (ROS)- and redox-dependent signaling by performing redox interactions with other proteins and modify their redox status. At present, PRX family identification, evolution and regulation research has been conducted in some plants; however, systematic research about this family is lacking in cotton. In this study, a total of 44 PRXs were identified in the cotton genome. Phylogenetic and conserved active site analyses showed that the PRXs were divided into six subfamilies according to the conserved site (PxxxTxxC…S…W/F) and conserved cysteinyl residues positions. Segmental duplication and polyploid events were the main methods for PRX family expansion, and the PRXs of diploid G. arboreum were the donors of PRXs in the D subgenomes of allotetraploid G. hirsutum and G. barbadense during the evolution of the PRX family. qRT-PCR analysis confirmed that cis-acting elements play important roles in regulating the expression of PRXs. Alternative splicing events occurred in GhPRX14-D that can increased the complexity of transcripts in G. hirsutum. Subcellular localization showed that most PRX members were located in chloroplasts, the cytoplasmic membrane and the nucleus. Our results provide systematic support for a better understanding of PRXs in cotton and a starting point for further studies of the specific functions of PRXs in cotton.
Hazardous Gas Analysis during Fire Investigation
Authors: Han Dong-Hun , Choi Sin-Woong , Lee So Yun
Published: January 2021

Various types of hazardous substances are generated at fire scenes. Firefighters usually use the self-contained breathing apparatus (SCBA) during firefighting; however, SCBA is very inconvenient to use in other works (e.g., fire investigation and fire scene commands). Therefore, firefighters can be exposed to numerous chemicals. In this study, concentrations of hazardous gases were measured by utilizing gas analyzers with seven sensors during fire investigations. Six fire investigators measured the concentrations of hazardous gases directly as they worked. This included capturing the maximum concentrations of SO2 at seven places, HCHO at 29 places, NO2 at one place, HCN at 13 places, and CO at two places where the concentration exceeded the short-term exposure limit (STEL). When reconstruction experiments were performed, the maximum allowable concentrations for most hazardous chemicals fell below the STEL approximately 90 min after the fire occurrence. Therefore, we determined that fire investigators should wear proper respiratory protective equipment when working.
Development of the Attachable Skin for Enhancing the Thermal Resistance of Robots
Authors: Pak Yejin , Jeong Sanghun , Jung Hoeryong , Kim Hyeong-Geun , Jang Handdeut , Kim Yeongjin
Published: January 2021

Intense heat from fire can result in significant damage to firefighting robots. To avoid this damage, numerous studies have been conducted on the thermal insulation of firefighting robots using electrical motors and sensors that can not withstand high temperatures. In this paper, we present an attachable skin for enhancing the thermal resistance of firefighting robots using polydimethylsiloxane (PDMS), where a wet chemical extinguishing agent is injected into the holes on PDMS. The pilot experiment was conducted to verify the thermal insulation performance of a wet chemical extinguishing agent compared to water. Several experiments were also carried out with different diameters, depths, shapes, and degrees of PDMS holes to determine optimum hole dimensions. The results demonstrated that the thermal resistance of PDMS skin is related to the capacity of the wet chemical extinguishing agent. In addition, the performance of the PDMS skin can be verified by its variation according to the ignition time.
Quantitative Analysis of Valve Contribution to the Failure Probability of Carbon Dioxide Suppression System
Authors: Yim Hyun-Tae , Kim Joo-Sung
Published: January 2021

Carbon dioxide suppression systems are used in nuclear power plants to extinguish oil fires and ensure integrity of critical equipment. In this study, the contributions of the valves in the carbon dioxide suppression system to the failure probability of suppression were quantitatively analyzed, and the failure probability of the fire suppression system applied to the fire Probabilistic Safety Assessment (PSA) was evaluated for appropriateness. Then, a reliability evaluation model was developed in the form of a fault tree, and the reliability data were analyzed for the major component. The failure probability of the carbon dioxide suppression system with early air-release equipment was assessed as 6.22 × 10-3/demand, which is 2.67 times that of the system without such equipment. The results were attributed to the addition of the diverted line isolation valves and quick exhaust valve to release residual air into the atmosphere before supplying carbon dioxide to the fire area. It was also confirmed that the failure probability of the carbon dioxide suppression system with the early air-release equipment was 15.6% that of the suppression provided by the fire PSA and that the failure probability of suppression by the fire PSA was conservative. There are no reported guidelines in literature for analyzing the reliabilities of carbon dioxide fire suppression systems, and the fire PSA currently use the failure probability of suppression recommended by the NSAC-179L.
Development of Standards for Production of an Exit Sign Lighting to Minimize Human Reaction Time - Part I: The Minimum Effective Dimensions
Authors: Oh Ryun-Seok , Choi Jun-Ho
Published: January 2021

Based on National Fire Safety Codes 303 in Korea, the size of an exit sign lighting to be installed is determined according to space use. Accordingly, a small exit sign lighting can be installed in a large area, which causes problems in the visual recognition of the exit sign lighting by occupants and increases the time required for evacuation. Therefore, in this study, human reaction time measurement experimental tests were conducted in a virtual reality environment to analyze the minimum effective dimension of an exit sign lighting. It was found that the minimum effective dimension of emergency exit sign lighting should be set to a length of 255 mm or more on one side of a 1:1 square display surface.
A Study on Alternative Foam Agents for Model Approval Test of Foam Extinguishing System
Authors: Jung Jae-Han , Park Seung-Geun , Lim Woo-Sub , Oh Jae-Sung
Published: January 2021

In this study, the performance of foam agents and test foam is compared and analyzed through experiments. The line proportioner method is used to release the foam agents at a mixing ratio of 1% and 3%. The inlet/outlet circumference of the proportioner is 40 A, and foam regulators are used at 1% and 3%, respectively. The basic variables such as flow rate, pressure, and measurement time are maintained at 200 LPM, 350 kPa, and 60 s, and the change in the mixing ratio is analyzed in the order of water, alcohol foam, and test foam. The experimental data processing method is carried out in accordance with the regulations of Korea Fire Institute (KFI). In the case of the test foam 1% mixing experiment, the performance is certified because the average emission mixing ratio is 1.19%, which is within the range of 1~1.3%. In the case of the test foam 3% mixing experiment, the average emission mixing ratio is 3.05%, which is within the range of 3~3.9%.
Genetic Divergence in Sorghum [Sorghum bicolor (L.) Moench] Genotypes under Contrasting Moisture Environments
Authors: Kebede Firezer Girma
Published: January 2021

Sorghum is one of the most important cereal crops in Ethiopia which is grown most dominantly in the low land area where drought predominates. In this area farmer’s preference to improved sorghum variety is dependent on earliness and drought tolerance traits. The objective of the study was to evaluate the genetic diversity of early maturing sorghum genotypes for drought tolerance by using principal component and cluster analysis. Twenty three early maturing sorghum genotypes were phenotyped under post-flowering moisture stressed and non-stressed environment using RCBD design in adjacent experiment. The analysis of variance revealed significant variation among genotypes for most of the traits for both moisture environments. Post-flowering drought reduce the value for all of the traits except flag leaf area and average grain yield was reduced by 21%. Five genetically divergent clusters which showed significant inter cluster distance were observed in both environments. Genotypes in cluster one showed best performance for grain yield and yield components under non-stress environment. Under stressed environment, genotypes under C1, and C2 revealed best performance for drought tolerance and yield traits, respectively. Therefore, the performance of genotypes under these clusters and different clustering pattern observed depicts the divergence of genotypes for drought response which creates opportunity for further improvement through selection and hybridization. Principal component analysis revealed five and seven PC captured 80% and 87% of total variation observed under stressed and non-stressed environment, respectively.
Pre-Service Teachers Achievement and Mastery Levels in Solid Geometry at E. P. College of Education, Bimbilla-Ghana
Authors: Salifu Anas Seidu
Published: January 2021

The purpose of the study was to determine Pre-Service Teachers (PSTs) achievement levels and self-evaluation of their level of mastery in Solid Geometry. The study used descriptive research design with purely quantitative approach to collect data related to Evangelical Presbyterian (E.P.) College of Education, Bimbilla-Ghana Pre-Service Teachers’. The population was one hundred and ninety-two (192) level 200 PSTs Pre-Service Teachers either majoring in mathematics, ICT or science. The sample used for the study was 140. Convenient, purposive and simple random sampling techniques were adopted. The instruments used were two comprising of achievement test and closed ended questionnaire. The overall results from the achievement test indicate that the PSTs were at good mastery level in solid geometry. Also, the self –evaluation questionnaire mastery levels for geometric properties, drawing of solid nets, finding surface areas were high and finding volume of solids were also very high. Finally, finding on composite solids area and volume was at moderate level. It was recommended that College Mathematics Tutors should encourage PSTs to always draw nets of solid shapes and also use solid nets to form solid shapes.
Some Geometry of Affine Immersion of General Co-dimension
Authors: Longwap Silas , Nahum Homti E. , Bitrus Gukat G.
Published: January 2021

After a careful study of some works of servaral authors on affine immersion of co-dimension one [1], co-dimension two [2], co-dimension three [3] and co-dimension four [4], we extend some of thier fundamental equations to affine immersion of genaral co-dimension p. Furthermore, we extend some theorem of Frank Dillen at el in [5] to affine immersion of general co-dimension and obtain the divisibility of the cubic forms by the second fundamental forms.
Coding triplets in the tRNA acceptor‐TΨC arm and their role in present and past tRNA recognition
Authors: Agmon Ilana , Fayerverker Itay , Mor Tal
Published: January 2021

The mechanism and evolution of the recognition scheme between key components of the translation system, that is, tRNAs, synthetases, and elongation factors, are fundamental issues in understanding the translation of genetic information into proteins. Statistical analysis of bacterial tRNA sequences reveals that for six amino acids, a string of 10 nucleotides preceding the tRNA 3' end carries cognate coding triplets to nearly full extent. The triplets conserved in positions 63–67 are implicated in the recognition by the elongation factor EF‐Tu, and those conserved in positions 68–72, in the identification of cognate tRNAs, and their derived minihelices by class IIa synthetases. These coding triplets are suggested to have primordial origin, being engaged in aminoacylation of prebiotic tRNAs and in the establishment of the canonical codon set.
Lightweight, Superelastic, and Hydrophobic Polyimide Nanofiber /MXene Composite Aerogel for Wearable Piezoresistive Sensor and Oil/Water Separation Applications
Authors: Liu Hu , Chen Xiaoyu , Zheng Yanjun , Zhang Dianbo , Zhao Ye , Wang Chunfeng , Pan Caofeng , Liu Chuntai , Shen Changyu
Published: January 2021

Inspired by the ultralight and structurally robust spider webs, flexible nanofibril‐assembled aerogels with intriguing attributes have been designed for achieving promising performances in various applications. Here, conductive polyimide nanofiber (PINF)/MXene composite aerogel with typical “layer‐strut” bracing hierarchical nanofibrous cellular structure has been developed via the freeze‐drying and thermal imidization process. Benefiting from the porous architecture and robust bonding between PINF and MXene, the PINF/MXene composite aerogel exhibits an ultralow density (9.98 mg cm−3), intriguing temperature tolerance from ‐50 to 250 °C, superior compressibility and recoverability (up to 90% strain), and excellent fatigue resistance over 1000 cycles. The composite aerogel can be used as a piezoresistive sensor, with an outstanding sensing capacity up to 90% strain (corresponding 85.21 kPa), ultralow detection limit of 0.5% strain (corresponding 0.01 kPa), robust fatigue resistance over 1000 cycles, excellent piezoresistive stability and reproductivity in extremely harsh environments. Furthermore, the composite aerogel also exhibits superior oil/water separation properties such as high adsorption capacity (55.85 to 135.29 g g−1) and stable recyclability due to its hydrophobicity and robust hierarchical porous structure. It is expected that the designed PINF/MXene composite aerogel can supply a new multifunctional platform for human bodily motion/physical signals detection and high‐efficient oil/water separation.
Next‐Generation Vaccines: Nanoparticle‐Mediated DNA and mRNA Delivery
Authors: Ho William , Gao Mingzhu , Li Fengqiao , Li Zhongyu , Zhang Xue‐Qing , Xu Xiaoyang
Published: January 2021

Nucleic acid vaccines are a method of immunization aiming to elicit immune responses akin to live attenuated vaccines. In this method, DNA or messenger RNA (mRNA) sequences are delivered to the body to generate proteins, which mimic disease antigens to stimulate the immune response. Advantages of nucleic acid vaccines include stimulation of both cell‐mediated and humoral immunity, ease of design, rapid adaptability to changing pathogen strains, and customizable multiantigen vaccines. To combat the SARS‐CoV‐2 pandemic, and many other diseases, nucleic acid vaccines appear to be a promising method. However, aid is needed in delivering the fragile DNA/mRNA payload. Many delivery strategies have been developed to elicit effective immune stimulation, yet no nucleic acid vaccine has been FDA‐approved for human use. Nanoparticles (NPs) are one of the top candidates to mediate successful DNA/mRNA vaccine delivery due to their unique properties, including unlimited possibilities for formulations, protective capacity, simultaneous loading, and delivery potential of multiple DNA/mRNA vaccines. This review will summarize the many varieties of novel NP formulations for DNA and mRNA vaccine delivery as well as give the reader a brief synopsis of NP vaccine clinical trials. Finally, the future perspectives and challenges for NP‐mediated nucleic acid vaccines will be explored.
A Programmable DNA‐Silicification‐Based Nanocavity for Single‐Molecule Plasmonic Sensing
Authors: Liang Le , Zheng Peng , Zhang Chi , Barman Ishan
Published: January 2021

Plasmonic nanocavities are highly desirable for optical sensing because of their singular ability to confine light into deep subwavelength volumes. Yet, it remains profoundly challenging to fabricate structurally resilient nanocavities with high fidelity, and to obtain direct, noninvasive visualization of the plasmonic hotspots within such constructs. Herein, highly precise and robust nanocavities, entitled DNA‐silicified template for Raman optical beacon (DNA‐STROBE), are engineered by using silicified DNA scaffolds for spatial organization of discrete plasmonic nanoparticles. In addition to substantially enhancing structural stability and chemical inertness, DNA silicification significantly improves nanogap control, resulting simultaneously in large and controlled local electromagnetic field enhancement. The ultrasmall mode volume of the DNA‐STROBE constructs promotes single‐molecule occupancy enabling surface‐enhanced Raman spectroscopy (SERS) observations of single‐molecule activity even at elevated background concentration, significantly relaxing the restrictive pico‐ to nanomolar molecular concentration condition typically required for such investigations. Additionally, leveraging super‐resolution SERS measurements allows noninvasive and diffraction‐unlimited spatial profiling of otherwise unresolvable plasmonic hotspots. The highly programmable and reproducible nature of the DNA‐STROBE, coupled with its quantitative label‐free molecular readouts, provides a versatile platform with applications across the spectrum of nanophotonics and biomedical sciences.
High‐Resolution Agent‐Based Modeling of COVID‐19 Spreading in a Small Town
Authors: Truszkowska Agnieszka , Behring Brandon , Hasanyan Jalil , Zino Lorenzo , Butail Sachit , Caroppo Emanuele , Jiang Zhong‐Ping , Rizzo Alessandro , Porfiri Maurizio
Published: January 2021

Amid the ongoing COVID‐19 pandemic, public health authorities and the general population are striving to achieve a balance between safety and normalcy. Ever changing conditions call for the development of theory and simulation tools to finely describe multiple strata of society while supporting the evaluation of “what‐if” scenarios. Particularly important is to assess the effectiveness of potential testing approaches and vaccination strategies. Here, an agent‐based modeling platform is proposed to simulate the spreading of COVID‐19 in small towns and cities, with a single‐individual resolution. The platform is validated on real data from New Rochelle, NY—one of the first outbreaks registered in the United States. Supported by expert knowledge and informed by reported data, the model incorporates detailed elements of the spreading within a statistically realistic population. Along with pertinent functionality such as testing, treatment, and vaccination options, the model accounts for the burden of other illnesses with symptoms similar to COVID‐19. Unique to the model is the possibility to explore different testing approaches—in hospitals or drive‐through facilities—and vaccination strategies that could prioritize vulnerable groups. Decision‐making by public authorities could benefit from the model, for its fine‐grain resolution, open‐source nature, and wide range of features.
A Commercial Benchmark: Light‐Soaking Free, Fully Scalable, Large‐Area Organic Solar Cells for Low‐Light Applications
Authors: Luke Joel , Corrêa Luiza , Rodrigues Jair , Martins Juliana , Daboczi Matyas , Bagnis Diego , Kim Ji‐Seon
Published: January 2021

Low‐light applications provide an exciting market opportunity for organic solar cells (OSCs). However, so far, studies have only considered OSCs of limited commercial viability. Herein, the applicability of a fully‐scalable, flexible, inverted non‐fullerene acceptor (NFA) containing OSC is demonstrated by showing its superior performance to silicon under low‐light, achieving 40 µW cm−2 maximum power output at 1300 lx illumination. The effect of parasitic resistance and dark current on low‐light performance are identified. Furthermore, an atmosphere sensitive light‐soaking (LS) effect, critical for low‐light performance and resulting in undesirable S‐shaped current‐voltage characteristics, is analyzed. By employing different interlayers and photoactive layers (PALs) the origin of this LS effect is identified as poor electron extraction at the electron transport layer (ETL)/PAL interface when the common ETL ZnO is used. Two strategies are implemented to overcome the LS effect: replacement of ZnO with SnO2 nanoparticles to reduce ETL sub‐gap electron trap states or tuning the NFA energy levels to optimize interfacial energetics. Finally, the commercial viability of these LS‐free devices is demonstrated by fabricating fully printed large‐area modules (21.6 cm2) achieving a maximum power output of 17.2 µW cm−2, providing the most relevant example of the currently obtainable performance in commercial low‐light OSCs.
Conservation tillage is compatible with manure injection in corn silage systems
Authors: Battaglia Martin L. , Ketterings Quirine M. , Godwin Gregory , Czymmek Karl J.
Published: January 2021

Adoption of conservation tillage practices has increased over the past 30 yr in the United States. Research is needed to evaluate if reduced tillage practices are compatible with manure injection on dairy farms. Two corn (Zea mays L.) silage studies were conducted in New York to evaluate the impact of zone tillage depth and tillage intensity on early plant growth and soil nitrate‐N, corn silage productivity and quality, and nutrient uptake at harvest. Treatments included three zone tillage depths (0, 18, and 36 cm; with aerator seedbed preparation) for Study 1 (2012–2013) and three tillage intensities (no tillage, reduced tillage [aerator seedbed preparation without zone tillage], and intensified reduced tillage [aerator seedbed preparation plus zone tillage at 18‐cm depth]) for Study 2 (2014–2016). Manure was injected in the spring, and all fields had a manure and zone tillage history. Zone tillage depth did not affect early plant growth, soil nitrate‐N content at V5‐V6, corn silage yield, quality, corn stalk nitrate test (CSNT)‐N, or nutrient removal with harvest. The CSNT‐N levels exceeded 2,000 mg NO3–N kg–1, confirming sufficient N for each treatment. Study 2 showed no impact of tillage intensity on corn growth, yield, or nutritive value, and CSNT‐N levels always exceeded 2,000 mg NO3–N kg–1. These findings show that, on fields with a history of manure addition and reduced tillage, manure injection followed by planting without further seedbed preparation or zone tillage can maintain yields and quality and can conserve N while reducing soil disturbance and tillage‐associated fuel, equipment, and labor costs.
A Desaturase‐Like Enzyme Catalyzes Oxazole Formation in Pseudomonas Indolyloxazole Alkaloids
Authors: Brachmann Alexander O. , Probst Silke I. , Rüthi Joel , Dudko Darya , Bode Helge B. , Piel Jörn
Published: January 2021

Indolyloxazole alkaloids occur in diverse micro‐ and macroorganisms and exhibit a wide range of pharmacological activities. Despite their ubiquitous occurrence and simple structures, the biosynthetic pathway remained unknown. Here, we used transposon mutagenesis in the labradorin producer Pseudomonas entomophila to identify a cryptic biosynthetic locus encoding an N‐acyltransferase and a non‐heme diiron desaturase‐like enzyme. Heterologous expression in E. coli demonstrates that both enzymes are sufficient to produce indolyloxazoles. Probing their function in stable‐isotope feeding experiments, we provide evidence for an unusual desaturase mechanism that generates the oxazole by decarboxylative cyclization.
Imaging and Analysis of Isomeric Unsaturated Lipids through Online Photochemical Derivatization of Carbon–Carbon Double Bonds**
Authors: Unsihuay Daisy , Su Pei , Hu Hang , Qiu Jiamin , Kuang Shihuan , Li Yingju , Sun Xiaofei , Dey Sudhansu K. , Laskin Julia
Published: January 2021

Unraveling the complexity of the lipidome requires the development of novel approaches for the structural characterization of lipid species with isomer‐level discrimination. Herein, we introduce an online photochemical approach for lipid isomer identification through selective derivatization of double bonds by reaction with singlet oxygen. Lipid hydroperoxide products are generated promptly after laser irradiation. Fragmentation of these species in a mass spectrometer produces diagnostic fragments revealing the C=C locations in the unreacted lipids. This approach uses an inexpensive light source and photosensitizer making it easy to incorporate into any lipidomics workflow. We demonstrate the utility of this approach for the shotgun profiling of C=C locations in different lipid classes present in tissue extracts using electrospray ionization (ESI) and ambient imaging of lipid species differing only by the location of C=C bonds using nanospray desorption electrospray ionization (nano‐DESI).
Interrupted Pyridine Hydrogenation: Asymmetric Synthesis of δ‐Lactams
Authors: Wagener Tobias , Lückemeier Lukas , Daniliuc Constantin G. , Glorius Frank
Published: January 2021

Metal‐catalyzed hydrogenation is an effective method to transform readily available arenes into saturated motifs, however, current hydrogenation strategies are limited to the formation of C−H and N−H bonds. The stepwise addition of hydrogen yields reactive unsaturated intermediates that are rapidly reduced. In contrast, the interruption of complete hydrogenation by further functionalization of unsaturated intermediates offers great potential for increasing chemical complexity in a single reaction step. Overcoming the tenet of full reduction in arene hydrogenation has been seldom demonstrated. In this work we report the synthesis of sought‐after, enantioenriched δ‐lactams from oxazolidinone‐substituted pyridines and water by an interrupted hydrogenation mechanism.
Benzo‐Fused Perylene Oligomers with up to 13 Linearly Annulated Rings
Authors: Yang Xuan , Rominger Frank , Mastalerz Michael
Published: January 2021

The longer acenes with more than six linearly fused six‐membered rings are still fascinating chemists and physicists because of their unique photophysical properties and their high potential for organic electronics applications. Unfortunately, with increasing size (seven and more rings) these compounds rapidly lose chemical stability. Besides kinetic and chemical stabilization approaches introducing either bulky or electron‐withdrawing groups or both, such systems also have been stabilized by peri‐annulation. Although strictly spoken, these peri‐annulated compounds are no longer real acenes, they have fascinating properties as well. Herein, we describe the first synthesis of a new series of peri‐annulated acenes with up to 13 linearly fused rings, which is unprecedented till date. Furthermore, this new series contains perylene units connected through benzene rings along their [b,k]edges, responsible for unique absorption and emission properties.