bluuebunny/crossref_metadata_2025 huggingface dataset:
El derecho a decidir y el principio democrático
Authors: Tudela Aranda José
Published: July 2018

Decidida la independencia, las fuerzas políticas partidarias de la misma, tenían que encontrar la manera de poder encauzar sus aspiraciones. No teniendo cauce ni en derecho interno ni el derecho internacional, se busco ese cauce en el principio democrático mediante la construcción del llamado derecho a decidir. Un derecho a decidir que suponía, en esencia, reducir el principio democrático a un solo acto electoral, con reglas establecidas unilateralmente. En este artículo se pretende desmentir tanto la oposición entre principio de legalidad y principio democrático como la propia ortodoxia democrática del derecho a decidir. Junto a ello, se argumenta que en ningún caso resulta posible constitucionalizar, normativizar, un derecho de autodeterminación. Más allá de su naturaleza difícilmente compatible con la esencia de cualquier orden constitucional, las dificultades de fijar las condiciones concretas de su ejercicio, lo antojan imposible. No en vano, ningún ordenamiento jurídico del mundo lo reconoce.After having decided the objective of independence, the political parties in favour of this objective had to find a way how to articulate their aspirations. Since there is no legal way within the national or international law, the independence movement based their demands in the democratic principle by building the so-called right to decide. However this right to decide means to limit the democratic principle to a single electoral act, with unilaterally established rules and outside the existing legal framework. In this article we try to disprove both the supposed opposition between the rule of law and the democratic principle, as well as the supposed democratic spirit of the right to decide. Along with this, we will argue that it is impossible to constitutionalise the right of self-determination. The right of self-determination is opposed to the essence of any constitutional order, moreover the difficulties of setting the conditions in order to implement this right, and particularly, the definition of the subject, makes the application impossible.
El proceso independentista de Cataluña y la doctrina jurisprudencial: una visión sistemática
Authors: Bar Cendón Antonio
Published: July 2018

Este trabajo realiza una ordenación y un análisis sistemáticos de las decisiones adoptadas por el Tribunal Constitucional sobre el conjunto de las actuaciones de la Generalitat de Cataluña conducentes a la consecución de la independencia de esta Comunidad Autónoma, a partir del año 2013. Se trata de autos y sentencias que han producido una doctrina constitucional relevante, tanto sobre aspectos directamente afectados por el proceso independentista catalán —la soberanía de la nación española, la primacía de la Constitución, el referéndum—, como con respecto a otras cuestiones tangenciales. La conclusión del Tribunal Constitucional es que ni las mencionadas actuaciones de la Generalitat de Cataluña conducentes a la consecución de la independencia de esta Comunidad Autónoma, ni los instrumentos jurídicos utilizados hasta el presente con ese fin, tienen cabida ni en la Constitución Española de 1978 ni en el vigente Estatuto de Autonomía de Cataluña que de aquélla se deriva.This article realizes a systematic organization and analysis of the decisions taken by the Spanish Constitutional Court concerning the measures adopted by the Generalitat of Catalonia conducive to the attainment of independence by this Autonomous Community since 2013. The decisions analyzed here are final judgements and procedural judicial orders that have established relevant constitutional jurisprudence, as much on substantial issues directly affected by the Catalonian independence process — the sovereignty of the Spanish nation, the primacy of the Constitution, the referendum — as on other peripheral issues. The Constitutional Court concludes that neither the mentioned activities of the Generalitat of Catalonia conducive to the attainment of independence by this Autonomous Community, nor the legal instruments used so far for this purpose may be accepted within the framework of the Spanish Constitution of 1978 and the Statute of Autonomy of Catalonia, which is a constitutional offspring.
Control de armas en el nuevo federalismo americano
Authors: Martínez Sierra José Manuel , Mecinas Montiel Juan Manuel
Published: July 2018

En el presente trabajo se analizan las principales dimensiones constitucionales de la posesión de armas de fuego en los Estados Unidos de América: los derechos y libertades individuales, la seguridad pública, y la distribución de competencias entre la Federación y los Estados. En este análisis acudimos principalmente a la historia constitucional y a la hermenéutica de la doctrina constitucional del Tribunal Supremo americano, especialmente de las sentencias Heller y López. Se puede concluir que dicha jurisprudencia rompe dramáticamente con la progresiva federalización competencial desarrollada sobre la base de la cláusula comercial. A mayor abundamente, consideramos que actualmente no existen razones para un desarrollo constitucional favorable al control de armas.This paper analyses the main constitutional dimensions of gun possession in the United States of America: individual rights and freedoms, public safety and the distribution of powers between the Federation and the States. Our study focuses mainly in constitutional history and constitutional case law interpretation, especially in Heller and Lopez cases. We conclude that this case law breaks dramatically with the progressive federalization of competencies developed because of the commercial clause. Furthermore, we see no means for a constitutional development in favor of gun control.
La ductilidad del derecho a la protección internacional (refugio y protección subsidiaria) ante las crisis humanitarias: un desafío para Europa y para el sistema europeo común de asilo
Authors: García Mahamut Rosario
Published: July 2018

La presión insostenible en los sistemas nacionales de asilo especialmente de Grecia e Italia, generado por la grave crisis humanitaria y la tragedia vivida por cientos de miles de personas muchas de ellas en necesidad manifiesta de protección internacional, no ha conseguido mitigarse a través de los mecanismos de emergencia que la UE ha habilitado para hacerles frente. Esta situación ha evidenciado graves fallas en el sistema de protección internacional y deficiencias estructurales en el paquete normativo del actual SECA. Nuevos principios se han impuesto y la necesidad de reformar el SECA ya forma parte de la agenda europea. Este trabajo aborda un análisis detallado de los mecanismos habilitados por la UE para afrontar la crítica situación así como su impacto en una futura reforma del SECA.The unsustainable pressure concerning the national asylum systems, especially in Greece and Italy, generated by the severe humanitarian crisis and the tragedy undergone by hundreds of thousands of persons, many of them in clear need for international protection, has not managed to be mitigated throughout the emergency mechanisms taken to address them by the EU. This situation arouses serious flaws in the system of international protection and structural deficiencies in the regulatory package of the current CEAS. New principles have been developed, the need to reform the CEAS forms part and parcel of the current EU agenda. This research approaches not only a detailed analysis regarding to the mechanisms implemented by the EU to cope with the critical situation but also the impact on a future CEAS reform.
El régimen constitucional de los partidos políticos en el derecho de la Unión Europea: un equilibrio sui generis
Authors: Rodríguez Ángel
Published: July 2018

El equilibrio en la regulación de los partidos políticos en las democracias contemporáneas se alcanza cuando la atribución a estos de funciones políticas relevantes se compensa con mecanismos de control. La aplicación de este principio a la regulación de los partidos políticos en el derecho de la UE pone de manifiesto una situación de equilibrio sui generis: las funciones de los partidos políticos europeos en las elecciones europeas o en el proceso legislativo del Parlamento Europeo está fuertemente limitada por el protagonismo de los Estados miembros y la política de partidos nacionales; por otro lado, los mecanismos de control establecidos sobre los partidos políticos europeos, incluidos los de democracia militante, deben coexistir con las normas nacionales al respecto, generando los problemas típicos de los escenarios multinivel.Balance in political parties regulation is met in contemporary democracies when the attribution of relevant political functions to political parties is counterweighed with mechanisms of control. The application of this principle to the regulation of political parties under the EU legal order reveals a sui generis balance: the functions of European political parties in European elections or in the legislative process within the European Parliament is significantly limited by the leading role played by member States and national party politics; besides, the mechanisms of control on European political parties, including those of militant democracy, must coexist with national laws governing the same subject, creating the typical problems of multilevel scenarios.
Encuesta: el método comparado en Derecho constitucional
Authors: Aláez Corral Benito , Balaguer Callejón Francisco , Canosa Usera Raul , García Morales María Jesús , García Roca Javier , Pérez Tremps Pablo
Published: July 2018

En esta encuesta un grupo de Catedráticos de Derecho Constitucional contestan un conjunto de preguntas sobre el uso del método comparado en el derecho constitucional español, y sobre la influencia de modelos o referentes extranjeros durante el proceso constituyente, en la actividad legislativa y en la del Tribunal Constitucional, así como también algunas preguntas sobre los estudios de derecho constitucional comparado.In this academic survey a group of Constitutional Law Professors answer some questions about the role of the comparative method in the Spanish constitutional law, and the influence of foreign models in the constitutional process, the legislator and the Constitutional Court, as well as about the present situation of comparative constitutional law studies.
RESEÑA de: Bustos Gisbert, Rafael. "Calidad democrática. Reflexiones constitucionales desde la teoría, la realidad y el deseo". Marcial Pons ; Fundación Manuel Giménez Abad, 2017
Authors: Presno Linera Miguel Ángel
Published: July 2018

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Posturas, escotes, tacón y maquillaje: percepciones de universitarios sobre las niñas sexualizadas en revistas de moda
Authors: Narros González María José , Díaz-Bustamante Ventisca Mónica , Llovet Rodríguez Carmen
Published: July 2018

The image that media communicates of childhood creates stereotypes about them and influences their lifestyles. Specially, girls’ bodies are converted into a show by certain corporate culture that consider girls as consumer objects. In this context, we wonder how Spanish college students perceive girls showed by fashion magazines exhibiting sexualizing attributes. The study also explores the sexualizing power of the attributes perceived. Another aim is to determine if there are different segments of individuals based on the previous perceptions. An online survey was conducted among 449 college students (18-25 years old), conscious about the communication world. The objective was to determine the attributes considered more and less related with a sexualizing power. Results show that participants are highly sensitive to the sexualization of girls in fashion magazines. Contestants can identify attributes with a high sexualizing power in aspects regarding to stylish, make up, postures, corporal exhibition and language portrayed in the images. There are four groups clearly identified according to more and less sexualizing power linked to the attributes perceived. A first group does not assign a sexualizing power to the attributes that adultize girls. Secondly, there are individuals who do not notice any sexualizing power in the attributes studied. A third group perceives the sexualizing power in the attributes related to the corporal exhibition. Finally, a group that observes a high sexualizing power in all the attributes.
Análisis de la influencia de la publicidad en la prelectura de las marcas en niños de 4 a 5 años de la ciudad de Quito
Authors: Sánchez Calderón Hugo , Yánez Balarezo Samuel , Martínez Segovia Mayra
Published: July 2018

The development of the advertising activity also involves children of all ages who in the medium or long term become the future consumers of existing brands. Children of 4 and 5 years, without even learning to read, identify products by pre-reading the logo, symbols or identifying elements of the brand, which allows them to influence the purchase of the same. This is used by companies to position the product at an early age. Using techniques such as observation and interviewing, information is collected in day care centers and schools in the city of Quito, where different brands were shown to children to measure the level of positioning and recall. The study was supported by an interview with professors and experts in communication and advertising. We conclude that children from 4 to 5 years old through pre-reading, identify the brands that they are interested in and that have graphic elements that allow them to remember. It is also concluded that some of the brands have a long-term strategy to position brands in children as future consumers.
Three-dimensional Corporate Social Responsibility Model of a Postal Service Provider
Authors: Unterberger Marija , Vešović Predrag , Mostarac Katarina , Šarac Dragana , Ožegović Spasenija
Published: July 2018

In this paper, the term “corporate social responsibility” (CSR) was first observed based on the existing pyramid, which defines CSR as a set of economic, legal, ethical, and philanthropic activities. Then the dimensioning of the model of corporate responsibility in postal system was performed, where seven categories of the CSR model were defined. Only one category (out of seven) represents a set of all four activities defined by the existing pyramid. Based on this, a new model of CSR in the postal system was developed, that is seen through the development of three dimensions of the postal network: physical (PH), electronic (E), and financial (F). The main objective of the paper is to define a CSR model that will ensure the economic, social, and environmental development of the postal market by synergistic operation of all three dimensions of the postal network. An analysis of the existing state of the postal services market was carried out, and then the level of the future development of the postal network was determined. Through evaluation or systematic and objective assessment of the CSR model based on the determined parameters, measurability of the CSR model is assured. This paper deals with the case of the public postal operator (PPO) in the Republic of Serbia (RS).
La historia global y la globalidad histórica contemporánea
Authors: Fazio Vengoa Hugo , Fazio Vargas Luciana
Published: July 2018

A reflection on the present, its great transformations and epistemic challenges, served as starting point for the authors to consider the prominent place that social analyses confer to the “local-global” axis in the interpretation of contemporary phenomena. The interest by the local-global has brought up new metrics of time and space. It has also has enhanced the tendencies that homogenize and those that strengthen differences, which explains many of the transformations that the present societies experience. Based on this diagnosis, and in order to make the contemporary international/world-wide intelligible, the authors resort to the notion of global history, understood as the synchronization and the linking that registers the dissimilar historical trajectories, which enter in synchronicity, resonance and feedback in the context of globality.
Micro/macro: ¿local/global? El problema de la localidad en una historia espacializada
Authors: Torre Angelo
Published: July 2018

This paper discusses the possible local history boundaries within the paradigm of global history. Based on the questioning to the existing equation between local and global, by means of an analogy between micro and macro levels, the current research attempts to rebuild the methodological implications of the so-called “Spatial turn”. Likewise, it analyzes the contradictions of the metaphorical analysis of space. Particularly, this research will focus on the rejection to the endogenous explanations of global history. This, in turn, contributes to the highlighting of the analytical boundaries of the circulation paradigm on which this is, likewise, based on.
La agencia indígena y el giro hacia lo global
Authors: Wilde Guillermo
Published: July 2018

This article explores the problematic of the indigenous agency in the historical anthropology of Latin America. It aims to articulate it with the debates it raised by the so-called turn towards the global. The first part of the article focuses on the emergence of the indigenous agency and the reflection on the ways of non-Western historical consciousness. The second part deals with the reemergence of the imperial agent and its shift towards studies on Ibero-American borders. The third and final part, identifies some recent attempts to approach the global circulation of people, texts and objects, and the challenge presented to the treatment of indigenous agency. Studies with this approach reframe completely the problem of this agency. They also drive a theoretical reconceptualization of concepts such as culture and society, in continuity with discussions held several decades ago by micro-history and certain versions of socio-cultural anthropology.
NSF-mediated disassembly of on- and off-pathway SNARE complexes and inhibition by complexin
Authors: Choi Ucheor B , Zhao Minglei , White K Ian , Pfuetzner Richard A , Esquivies Luis , Zhou Qiangjun , Brunger Axel T
Published: July 2018

SNARE complex disassembly by the ATPase NSF is essential for neurotransmitter release and other membrane trafficking processes. We developed a single-molecule FRET assay to monitor repeated rounds of NSF-mediated disassembly and reassembly of individual SNARE complexes. For ternary neuronal SNARE complexes, disassembly proceeds in a single step within 100 msec. We observed short- (<0.32 s) and long-lived (≥0.32 s) disassembled states. The long-lived states represent fully disassembled SNARE complex, while the short-lived states correspond to failed disassembly or immediate reassembly. Either high ionic strength or decreased αSNAP concentration reduces the disassembly rate while increasing the frequency of short-lived states. NSF is also capable of disassembling anti-parallel ternary SNARE complexes, implicating it in quality control. Finally, complexin-1 competes with αSNAP binding to the SNARE complex; addition of complexin-1 has an effect similar to that of decreasing the αSNAP concentration, possibly differentially regulating cis and trans SNARE complexes disassembly.
Shining light on spindle positioning
Authors: Serra-Marques Andrea , Dumont Sophie
Published: July 2018

Optogenetic approaches are leading to a better understanding of the forces that determine the plane of cell division.
Stability of important antibodies for kidney disease: pre-analytic methodological considerations
Authors: Han Qiuxia , Li Songyan , Fu Bo , Liu Dongwei , Wu Maoqing , Yang Xiaoli , Cai Guangyan , Liu Zhangsuo , Chen Xiangmei , Zhu Hanyu
Published: July 2018

Background

The importance of circulating antibodies as biomarkers of kidney disease has recently been recognized. However, no study has systematically described the methodology of sample preparation and storage regarding antibodies as biomarkers of kidney disease. It remains unknown whether repetitive freeze-thaw cycles, physical disturbances, storage at different temperatures or for different periods of time, or haemolytic or turbid serum samples affect antibody measurements. The aim of this study was to investigate the stabilities of antibodies associated with kidney disease in serum samples under various relevant clinical and research conditions.

Methods

We stored serum samples in the following different conditions: repetitive freeze-thaw cycles (1, 6 or 12 times), long-term storage (7 or 12 months at −80 °C), physical disturbance (1 or 8 h), and storage at 4 °C (1, 3 or 6 weeks) and room temperature (1 or 7 days). The stabilities of the anti-phospholipase A2 receptor (anti-PLA2R), anti-glomerular basement membrane, anti-myeloperoxidase and anti-proteinase 3 antibodies were evaluated with enzyme-linked immunosorbent assays (ELISA).

Results

We found that repetitive freeze-thaw cycles did not have a significant effect on the stabilities of the abovementioned antibodies in clear serum samples. The ELISA readings of haemolytic and turbid serum samples tended to increase and decrease, respectively. Neither long-term storage at −80 °C nor physical disturbance had a significant effect on anti-PLA2R antibody stability in sealed serum samples. The concentrations of most of these antibodies increased in unsealed serum samples that were stored at 4 °C for more than 6 weeks or at room temperature for more than 7 days.

Discussion

Our findings revealed that the abovementioned circulating antibodies that are used as biomarkers for kidney disease had stable physicochemical properties, structures and immunoreactivities such that they were not influenced by repetitive freeze-thaw cycles, physical disturbances or long-term storage at −80 °C. However, the ELISA readings tended to change for haemolytic, turbid and unsealed serum samples.
A successful dental management in a child with Cornelia de Lange Syndrome:rare case of Cornelia de Lange Syndrome in child
Authors: Fernandez Clarissa Christina Avelar , Oliveira Queila Braga , Romanos Helena Freire , Fornasaria Marta Teresinha , Castro Gloria Fernanda Barbosa de Araújo
Published: July 2018

Background: the Cornelia de Lange Syndrome (CDLs) is a rare and complex syndrome characterized, basically, by psychomotor retardation associated with a number of congenital malformations. Aims: this paper reports the case of an 11-year-old female child diagnosed with Cornelia de Lange Syndrome (CdLS) and her successful dental management. Case report: the patient had severe mental retardation, definite negative behavior and the clinical findings included oral and physical changes. The patient's oral hygiene was deficient with the presence of calculus and gingivitis, besides several active caries lesions in permanent and deciduous dental elements. The treatment consisted in guidance for caregivers about oral hygiene and diet, and the dental procedures were performed under general anesthesia. Currently, the patient is accompanied by monthly follow-ups. Conclusions: the lack of knowledge about oral hygiene and cariogenic diets was identified as a one of the reasons for the oral diseases present. Due to the need to care for the other more serious and complex health problems, the oral diseases had evolved faster than usual and thus were difficult to treat and maintain thereafter. Under such conditions, the dentist plays a key role within a multidisciplinary team. From the guidance and knowledge provided in the dental clinic, there was a significant improvement in the life quality of the child and her family.
Feasibility of optimizing intensity‐modulated radiation therapy plans based on measured mucosal dose adjacent to dental fillings and toxicity outcomes
Authors: Seol Seung Won , Aggarwal Sonya , von Eyben Rie , Wang Ziwei , Chan Cato , Say Carmen , Xing Lei , Hara Wendy , Yang Yong , Le Quynh Thu
Published: July 2018

We prospectively investigated the feasibility of IMRT treatment plan optimization based on dosimeter measurements of lateral tongue mucosal dose adjacent to the dental fillings and evaluated dose‐toxicity relationship and factors affecting oral mucositis (OM) in head and neck cancer patients. Twenty‐nine head and neck cancer patients with metallic dental fillings who were scheduled to undergo fractionated external beam radiation therapy (RT) ± chemotherapy were enrolled. The lateral tongue dose was measured and if the calculated dose for the entire treatment was ≥35 Gy, a re‐plan was generated to reduce the lateral tongue mucosal dose. OM was graded weekly according to Common Terminology Criteria for Adverse Events version 4.0 and the patients completed the Oral Mucositis Weekly Questionnaire‐Head and Neck Cancer. The result showed that it was not feasible to optimize the IMRT plan based on measured tongue dose in most of the patients who needed re‐plan as re‐planning compromised the target coverage in 60% of these patients. The duration of grade (Gr) 2 OM was correlated with measured lateral tongue dose (P = 0.050). Concurrent cetuximab was significantly associated with faster onset of Gr2 OM than concurrent cisplatin (P = 0.006) and with longer duration of OM (P = 0.041) compared to concurrent cisplatin or IMRT‐alone. The pattern of reported pain over time was significantly different for each treatment type (RT and cetuximab, RT and cisplatin and RT‐alone) and depending on the dose level (P = 0.006). In conclusion, optimizing the IMRT plan based on measured lateral tongue dose was not feasible. Measured lateral tongue dose was significantly correlated with longer duration of OM ≥Gr2, and concurrent cetuximab was associated with earlier onset and longer duration of OM ≥Gr2.
A framework for clinical commissioning of 3D‐printed patient support or immobilization devices in photon radiotherapy
Authors: Meyer Tyler , Quirk Sarah , D'Souza Malgorzata , Spencer David , Roumeliotis Michael
Published: July 2018

Purpose

The objective of this work is to outline a framework for dosimetric characterization that will comprehensively detail the clinical commissioning steps for 3D‐printed materials applied as patient support or immobilization devices in photon radiotherapy. The complex nature of 3D‐printed materials with application to patient‐specific configurations requires careful consideration. The framework presented is generalizable to any 3D‐printed object where the infill and shell combinations are unknown.

Methods

A representative cylinder and wedge were used as test objects to characterize devices that may be printed of unknown, patient‐specific dimensions. A case study of a 3D‐printed CSI immobilization board was presented as an example of an object of known, but adaptable dimensions and proprietary material composition. A series of measurements were performed to characterize the material's kV radiologic properties, MV attenuation measurements and calculations, energy spectrum water equivalency, and surface dose measurements. These measurements complement the recommendations of the AAPM's TG176 to characterize the additional complexity of 3D‐printed materials for use in a clinical radiotherapy environment.

Results

The dosimetric characterization of 3D‐printed test objects and a case study device informed the development of a step‐by‐step template that can easily be followed by clinicians to accurately and safely utilize 3D‐printed materials as patient‐specific support or immobilization devices.

Conclusions

A series of steps is outlined to provide a formulaic approach to clinically commission 3D‐printed materials that may possess varying material composition, infill patterns, and patient‐specific dimensions.
Enhancement of megavoltage electronic portal images for markerless tumor tracking
Authors: Cheong Kwang‐Ho , Yoon Jai‐Woong , Park Soah , Hwang Taejin , Kang Sei‐Kwon , Koo Taeryool , Han Tae Jin , Kim Haeyoung , Lee Me Yeon , Kim Kyoung Ju , Bae Hoonsik
Published: July 2018

Purpose

The poor quality of megavoltage (MV) images from electronic portal imaging device (EPID) hinders visual verification of tumor targeting accuracy particularly during markerless tumor tracking. The aim of this study was to investigate the effect of a few representative image processing treatments on visual verification and detection capability of tumors under auto tracking.

Methods

Images of QC‐3 quality phantom, a single patient's setup image, and cine images of two‐lung cancer patients were acquired. Three image processing methods were individually employed to the same original images. For each deblurring, contrast enhancement, and denoising, a total variation deconvolution, contrast‐limited adaptive histogram equalization (CLAHE), and median filter were adopted, respectively. To study the effect of image enhancement on tumor auto‐detection, a tumor tracking algorithm was adopted in which the tumor position was determined as the minimum point of the mean of the sum of squared pixel differences (MSSD) between two images. The detectability and accuracy were compared.

Results

Deblurring of a quality phantom image yielded sharper edges, while the contrast‐enhanced image was more readable with improved structural differentiation. Meanwhile, the denoising operation resulted in noise reduction, however, at the cost of sharpness. Based on comparison of pixel value profiles, contrast enhancement outperformed others in image perception. During the tracking experiment, only contrast enhancement resulted in tumor detection in all images using our tracking algorithm. Deblurring failed to determine the target position in two frames out of a total of 75 images. For original and denoised set, target location was not determined for the same five images. Meanwhile, deblurred image showed increased detection accuracy compared with the original set. The denoised image resulted in decreased accuracy. In the case of contrast‐improved set, the tracking accuracy was nearly maintained as that of the original image.

Conclusions

Considering the effect of each processing on tumor tracking and the visual perception in a limited time, contrast enhancement would be the first consideration to visually verify the tracking accuracy of tumors on MV EPID without sacrificing tumor detectability and detection accuracy.
Atomic Layer Deposited TiO2–IrOx Alloy as a Hole Transport Material for Perovskite Solar Cells
Authors: Tan Wanliang , Hendricks Olivia L. , Meng Andrew C. , Braun Michael R. , McGehee Michael D. , Chidsey Christopher E. D. , McIntyre Paul C.
Published: July 2018

The hole transport layer (HTL) is one of the key components in planar perovskite solar cells. This study reports a new kind of HTL fabricated using atomic layer deposition (ALD). By alloying TiO2 with IrOx, it is demonstrated that TiO2, a well‐known electron‐selective contact and electron transport layer in photovoltaic devices, can behave as an HTL with an appropriately high work function. Perovskite Cs0.17FA0.83Pb(I0.83Br0.17)3 solar cells including this new hole transport material achieve a power conversion efficiency of 15.8% under AM 1.5G simulated solar irradiation compared to a 14.3% efficiency for otherwise‐identical devices incorporating a more standard NiO HTL layer. These results suggest the promise of transition metal oxide alloys synthesized by ALD as hole contact materials for optoelectronic devices, including advanced photovoltaics.
Thermoplasmonic and Photothermal Metamaterials for Solar Energy Applications
Authors: Shin Dongheok , Kang Gumin , Gupta Prince , Behera Saraswati , Lee Hyungsuk , Urbas Augustine M. , Park Wounjhang , Kim Kyoungsik
Published: July 2018

Sunlight is one of the Earth's clean and sustainable natural energy resources, and extensive studies are conducted on the conversion of solar energy into electricity using photovoltaic (PV) devices. However, single‐junction PV devices cannot break the theoretical efficiency limit known as the Shockley–Queisser limit that is caused by the sub‐bandgap transmission and heat dissipation losses in semiconductors. Solar thermal conversion approaches may provide an alternative way to exceed this limit and enable more efficient use of solar light than that in PV devices. Recently, spectrally or thermally engineered metamaterials have attracted considerable attention for solar energy applications because of their excellent physical properties. The recent research progress in the development of these photothermal and thermoplasmonic metamaterials, along with their promising applications in solar thermophotovoltaics, radiative cooling, and solar desalination, is discussed.
Large‐Area 3D‐Printed Chiral Metasurface Composed of Metal Helices
Authors: Golod Sergey V. , Seyfi Valentin A. , Buldygin Anatoly F. , Gayduk Alexey E. , Prinz Victor Ya.
Published: July 2018

An original design for chiral metasurfaces formation is proposed. The hybrid fabrication approach is based on the 3D printing of polymer substrates with a shape‐generating “helical” relief, molding, and subsequent shadow metal deposition. The formed double‐layer grating of multiturn metal helices rotates the polarization plane of sub‐terahertz and microwave radiation through an angle in excess of 40°. Both experimentally and in numerical simulations, it is demonstrated that re‐reflection phenomena occur in the “metal helix–polymer substrate” hybrid structure. Those phenomena permit control of polarization‐plane rotation, ellipticity, and asymmetric transmission. Multiplication of printed structures with 3D helices achieved by using the molding technique enables the formation of large‐area chiral metasurfaces. The advantages of the proposed metasurface include easy fabrication of the system, the possibility of its scalability to other frequency ranges, and the possibility of using systems based on such metasurfaces in highly efficient polarization transformers.
Impact of Tumor Necrosis Factor Inhibitor Versus Nonsteroidal Antiinflammatory Drug Treatment on Radiographic Progression in Early Ankylosing Spondylitis: Its Relationship to Inflammation Control During Treatment
Authors: Park Jun Won , Kim Min Jung , Lee Jeong Seok , Ha You‐Jung , Park Jin Kyun , Kang Eun Ha , Lee Yun Jong , Song Yeong Wook , Lee Eun Young
Published: July 2018

Objective

To investigate the impact of tumor necrosis factor inhibitor (TNFi) treatment and inflammation control on radiographic progression in early ankylosing spondylitis (AS) over 4 years.

Methods

We included a total of 215 patients with early AS (symptom duration <10 years) treated with TNFi (the TNFi group; n = 135) or with nonsteroidal antiinflammatory drugs (NSAIDs) (the control group; n = 80). Two blinded readers assessed radiographic progression using the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). Inflammation control was inferred from C‐reactive protein (CRP) levels time‐averaged between 2 radiologic assessments. Linear mixed modeling was used to estimate mSASSS changes over radiographic intervals as well as the impact of clinical factors on outcomes.

Results

The TNFi group had longer disease duration, a higher baseline CRP level, and a higher Bath Ankylosing Spondylitis Disease Activity Index than did controls. The time‐averaged CRP level over radiographic intervals was lower with TNFi treatment than with NSAID treatment (mean ± SD 0.27 ± 0.30 mg/dl versus 0.61 ± 0.68 mg/dl; P < 0.001). Overall, mean ± SD mSASSS change over the 2‐year interval was 1.30 ± 2.97 units. In the multivariable model adjusted for age, smoking status, baseline CRP level, and the presence of syndesmophytes at baseline, the TNFi group showed less mSASSS change over the 2‐year interval (β = −0.90 [95% confidence interval {95% CI} −1.51, −0.29]). However, when a time‐averaged CRP level was additionally included, it significantly influenced the mSASSS change (β = 1.02 [95% CI 0.32, 1.71]), decreasing the estimated group difference (β = −0.52 [95% CI −1.17, 0.14]). NSAID indices of both groups were not associated with either time‐averaged CRP levels or mSASSS changes.

Conclusion

Effective suppression of inflammation by TNFi treatment decreases radiographic progression in early AS.
Oberflächennahe Geothermiesondenanlagen im Betrieb
Authors: Wagner Isabel M.
Published: July 2018

Kleine oberflächennahe Geothermiesondenanlagen mit einer Heizleistung < 30 kW werden in Deutschland insbesondere bei Wohnimmobilien zahlreich betrieben. Dennoch ist wenig über ihren Betrieb, ihre Zuverlässigkeit und die Zufriedenheit der Eigentümer der geothermischen Sondenanlagen bekannt. Eine in den Städten Wiesbaden, Darmstadt, Düsseldorf und Frankfurt am Main durchgeführte Praxisstudie in Form einer schriftlichen Erhebung bei den Eigentümern gewährt hier Einblick und dokumentiert eine sehr große Zufriedenheit mit dem Betrieb der Anlagen, sehr wenig Ausfälle sowie eine hohe Anzahl an auch zur Kühlung verwendeten Geothermiesondenanlagen. In Abhängigkeit von der vorhandenen Grundwasserströmung im Untergrund erzeugen geothermische Anlagen Temperaturfahnen im Untergrund in Richtung der Grundwasserströmung, die eine thermische Interaktion benachbarter Geothermiesondenanlagen verursachen können. Hier knüpft die Frage nach den erforderlichen Grenzabständen zu Nachbargrundstücken an. Untersucht wird in Anlehnung an die Umfrageergebnisse die Abhängigkeit der Entwicklung der Temperaturfahne insbesondere von der Betriebsweise der geothermischen Anlage. Der Einfluss einer zusätzlichen Kühlung, die gemäß der Praxisstudie vermehrt eingesetzt wird, kann zu einer Reduzierung der Temperaturfahnenausbreitung und damit der thermischen Interaktion führen, sodass die Betriebsweise der Sondenanlage maßgeblichen Einfluss auf die erforderlichen Grenzabstände hat.
Cellulosefaser‐Leichtbeton (CFLC)
Authors: Thiel Thomas , Grieger Christoph , Mechtcherine Viktor
Published: July 2018

Im Mittelpunkt dieses Artikels steht ein zementgebundener Leichtbeton auf der Basis von aus Altpapier herausgelösten Cellulosefasern. Die Herstellung dieses neuartigen Leichtbetons basiert im Wesentlichen auf einer Vermischung von aus Altpapier gewonnenen Cellulosefasern und Zementleim. Durch die Variation des Faseranteils lässt sich ein breites Spektrum an Rohdichtewerten erzielen; bei hohen Fasergehalten können nahezu dämmstofftypische Eigenschaften realisiert werden.

Am Anfang stehen Erläuterungen zur Spezifik dieses Materials und eine Einordnung in den Kontext der üblichen Leicht‐ und Faserbetone. Es folgen weiterhin Betrachtungen zur Problematik des Faseraufschlusses. In diesem Zusammenhang werden Wege aufgezeigt, wie dieser Prozess in betontechnologischer Hinsicht umgesetzt werden kann. Ferner wird der für einen zielgerichteten Mischungsentwurf entwickelte Algorithmus erläutert.

Durch die Faserzugabe wird gegenüber konventionellem Beton eine deutliche Änderung der rheologischen Eigenschaften hervorgerufen. Dies spiegelt sich in einer hierauf abgestimmten Einbau‐ und Verdichtungstechnologie sowie in einer Differenzierung in drei verschiedene CFLC‐Grundtypen wider. Für die Konsistenzprüfung wird ein geeignetes Verfahren vorgestellt. Abschließend wird das Spektrum der mit diesem Material erreichbaren Frisch‐ und Festbetoneigenschaften aufgezeigt.
Electrochemical and Morphological Characterization of Zn−Al−Cu Layered Double Hydroxides as a Negative Electrode in Aqueous Zinc‐Ion Batteries
Authors: Bani Hashemi A. , Kasiri G. , Glenneberg J. , Langer F. , Kun R. , La Mantia F.
Published: July 2018

The front cover artwork is provided by Universität Bremen, Energy Storage and Energy Conversion Research Group and Innovative Sensor and Functional Materials Research Group. The image shows how layered double hydroxides can contribute to the improvement of the performances of the zinc anode in aqueous zinc‐ion batteries for the short‐term storage of renewable energies. Read the full text of the Article at 10.1002/celc.201800291.
Ermittlung des Pfahlgruppeneffekts einer Zweiergruppe offener Stahlrohrpfähle in Sand
Authors: Wisotzki Elmar , Foglia Aligi , Schallert Matthias , Quiroz Tulio
Published: July 2018

Die Offshore‐Windenergie ist eine wesentliche Stütze der Deutschen Energiewende. Offshore‐Konverterplattformen bündeln und transformieren hierbei die erzeugte elektrische Energie und speisen diese in das Übertragungsnetz ein. Diese Plattformtypen werden im Wesentlichen mit Stahlrohrrammpfählen tiefgegründet. Aufgrund der hohen Lasten kommen auch Pfahlgruppen zum Einsatz. Aus der Literatur ist bekannt, dass die Tragfähigkeit von Pfählen innerhalb einer Pfahlgruppe abweichend zur Tragfähigkeit von identischen Einzelpfählen sein kann. Hierbei spielen insbesondere der Abstand der Pfähle untereinander, der Pfahltyp sowie die Anordnung innerhalb der Gruppe eine Rolle. Zur Untersuchung des Tragverhaltens von Zweierpfahlgruppen für eine Offshore‐Plattform wurden daher im Testzentrum Tragstruktur Hannover (TTH) großmaßstäblich Versuche im Maßstab 1:10 ausgeführt. Das Testprogramm umfasste hierbei einerseits zeitversetzte dynamische Pfahlprobebelastungen an Einzelpfählen und andererseits statische Pfahlprobebelastungen an Einzelpfählen und Pfahlgruppen mit dem Ziel, die Pfahlgruppeneffektivität zu bestimmen, aber auch zeitabhängige Tragfähigkeitssteigerungen nachzuweisen.

In diesem Beitrag werden die experimentellen Untersuchungen sowie Ergebnisse vorgestellt und diskutiert. Für die hier getestete Pfahlkonfiguration konnte eine Pfahlgruppeneffektivität für die Grenzzustände der Gebrauchstauglichkeit und der Tragfähigkeit von etwa 1 nachgewiesen werden.
Enhancing the Proficiency of Water Use in Wheat Through Nitrogen Forms, Irrigation Intervals and Soil Conditioners
Authors: Abdou S.M.M. , Azza R. Ahmed , Naresh Kumar S. , Farrag F.R.M.
Published: July 2018

Field experiments were carried out at the Tameia Agricultural Research Station, Fayoum Governorate, Egypt, during the 2013/14 and 2014/15 seasons in order to study the impact of nitrogen fertilization forms, irrigation intervals and some soil conditioners on the yield, yield components and crop water relations of wheat (Giza 168). Two nitrogen forms with three irrigation intervals, i.e. I1: irrigation at 14 days, I2: 21 days and I3: 28 days with soil conditioners at the rate of 11.9 t ha‐1, i.e. C1control (without any addition), C2: compost, C3: rice straw and C4: sawdust with three replications in a split‐split plot design. Results indicate that the highest wheat grain yields in both years were detected from a combination of applying liquid ammonia gas, irrigation at 14‐day intervals and addition of compost. This treatment also gave higher values for yield components, uptake of nitrogen, phosphorus and potassium and their concentration in the grain. Further, it resulted in highest values for the consumptive use of water as well as water productivity. Thus, a combination of applying liquid ammonia gas, irrigation at 14‐day intervals and addition of compost can be adopted in wider areas in Egypt for enhanced wheat grain yield. © 2018 John Wiley & Sons, Ltd.
A new far‐field low‐frequency electromagnetic method for measurement of temporal variations in subsurface electrical conductivity averaged over a transect
Authors: Kiseleva Olga , Brandelik Alexander , Hübner Christof , Kalthoff Norbert , Kohler Martin , Königer Franz , Kottmeier Christoph
Published: July 2018

The new far‐field low‐frequency electromagnetic method used the electromagnetic ground wave from distant radio transmitters at low frequencies to estimate temporal variations of factors affecting subsurface electrical conductivity averaged along the propagation path between either a transmitter and a receiver or two receivers that are in line with a transmitter. Phase and phase difference between two receivers depend on three factors that influence the changes in electrical conductivity: soil moisture, depth to the groundwater table and soil temperature. This dependence was investigated by simulations and evaluated by an experiment. The measurement layout was based on simulating ground wave propagation over a layered subsurface using the surface impedance method and the Sommerfeld ground wave attenuation function. A three‐layer model for the subsurface was used, which includes a soil layer, an unsaturated vadose zone and a saturated groundwater zone. The results of simulations at a frequency of 77.5 kHz showed that the phase of the ground wave is strongly influenced by natural variation of the above‐mentioned three factors; 77.5 kHz is the carrier frequency of the Normal Time Service Germany (DCF77) in Mainflingen/Germany, that was chosen as a source of the low‐frequency radio waves used in the experiment. Over a 2‐year measurement period, the amplitude and phase of the ground wave were recorded with two receivers, one 70 km and the other 110 km away from the transmitter. Additionally, phase difference between the two receivers was calculated. In situ observations of soil moisture, depth to the groundwater table, and soil temperature along the transects under investigation were used to estimate phase and phase difference dependencies. Multiple regression analysis of the measured phase and phase difference revealed a strong dependence on the depth to the groundwater table and on soil temperature, whereas the impact of soil moisture on the phase and phase difference was found to be very low. Conversely, the relations obtained can be used to estimate the variation of the depth to the groundwater table, if the phase at a given frequency and the soil temperature information are available.
Effect of hybrid wollastonite with different nucleation and morphology on the crystallization and mechanical properties of polypropylene
Authors: Ding Qian , Zhang Zishou , Dai Xin , Li Mei , Mai Kancheng
Published: July 2018

In order to prepare polypropylene (PP) composites with balanceable stiffness and toughness, hybrid wollastonite with different nucleation and morphology as fillers were added into PP matrix. Nucleation efficiency (NE), crystallization behavior and melting characteristics, as well as the mechanical properties of hybrid wollastonite‐filled PP composites were systematically investigated using differential scanning calorimetry, wide‐angle X‐ray diffraction, mechanical testing, and scanning electron microscopy, respectively. The results indicated that the NE of wollastonite with β‐nucleation is much higher than that of acicular wollastonite and ultrafine wollastonite with α‐nucleation, and eventually hybrid wollastonite‐filled PP composites mainly form β‐phase PP. Furthermore, there exists cooperative effect between the reinforcement of wollastonite of different morphology and the toughening of β‐phase, which can be effectively controlled through regulating the nucleating ability, morphology, and mass ration of hybrid wollastonite. POLYM. COMPOS., 40:E638–E646, 2019. © 2018 Society of Plastics Engineers