bluuebunny/crossref_metadata_2025 huggingface dataset:
Multipoint high-fidelity CFD-based aerodynamic shape optimization of a 10 MW wind turbine
Authors: Madsen Mads H. Aa. , Zahle Frederik , Sørensen Niels N. , Martins Joaquim R. R. A.
Published: October 2018

Abstract. The wind energy industry relies heavily on CFD to analyze new turbine designs. To utilize CFD further upstream the design process where lower fidelity methods such as BEM are more common, requires the development of new tools. Tools that utilize numerical optimization are particularly valuable because they reduce the reliance on design by trial and error. We present the first comprehensive 3D CFD adjoint-based shape optimization of a modern 10&thisp;MW offshore wind turbine. The optimization problem is aligned with a case study from IEA Wind Task 37, making it possible to compare our findings with the BEM results from this case study, allowing us to determine the value of design optimization based on high-fidelity models. The comparison shows, that the overall design trends suggested by the two models do agree, and that it is particularly valuable to consult the high-fidelity model in areas such as root and tip where BEM is inaccurate. In addition, we compare two different CFD solvers to quantify the effect of modeling compressibility and to estimate the accuracy of the chosen grid resolution and order of convergence of the solver. Meshes up to 14 · 106 cells are used in the optimization whereby flow details are resolved. The present work shows that it is now possible to successfully optimize modern wind turbines aerodynamically under normal operating conditions using RANS models. The key benefit of a 3D RANS approach is that it is possible to optimize the blade planform and cross-sectional shape simultaneously, thus tailoring the shape to the actual 3D flow over the rotor, which is particularly important near the root and tip of the blade. This work does not address evaluation of extreme loads used for structural sizing, where BEM-based methods have proven very accurate, and therefore will likely remain the method of choice.
Arendt, Foucault: crítica de la filosofía política y arqueología de la acción
Authors: Carmona Hurtado Jordi
Published: October 2018

La hipótesis de este ensayo es que la fundación de la filosofía política, disciplina que Arendt definió como el intento de una huida completa de la política, puede entenderse como uno de los momentos decisivos de la conformación progresiva de lo que Foucault llamó la historia de la voluntad de saber occidental. A partir de esa suposición, examinamos en una lectura cruzada el análisis arendtiano del paso de la acción al gobierno en Platón y la lectura foucaultiana de la exclusión del sofisma en Aristóteles. Mostramos finalmente en qué la arqueología del mundo de la acción anterior a la filosofía política que Arendt propone, en torno a cierta figura ambigua de Sócrates, se diferencia de la teoría estratégica del discurso que Foucault encuentra en la sofística, y nos interrogamos por las implicaciones políticas de esta diferencia, especialmente en lo que apunta a repensar hoy las relaciones entre el pensamiento y la acción.
El trabajo vivo: la entelequia del capital
Authors: García Palacios Moisés
Published: October 2018

El trabajo vivo no es una categoría económica, sino que forma parte de la actividad práctica humana que surge del fundamento mismo de la vida. Sin embargo, en el sistema de producción capitalista el trabajo vivo es convertido en la determinación esencial del capital en su proceso de valorización. Así, mientras lo activo y lo subjetivo queda transformado en una objetividad muerta para los propios productores, el capital llega a su plena perfección con ello: el plusvalor. Partiendo de un análisis ontológico de la actividad laboral encontramos que el trabajo vivo es la categoría simple sobre la que se articula el resto de categorías económicas. La perspectiva filosófica ha de permitirnos analizar, mostrar y especificar las íntimas relaciones que se establecen entre el capital y el trabajo, así como las metamorfosis y transformaciones que ha de sufrir el trabajo vivo para convertirse en entelequia del capital, es decir, el tránsito de lo vivo a lo muerto.
Consumer sensory evaluation of honey across age cohorts in Slovakia
Authors: Šedí­k Peter , Kňazovická Vladimí­ra , Horská Elena , Kačániová Miroslava
Published: October 2018

The growing popularity of honey among consumers has caused many frauds and cases when honey of high quality is adulterated by cheap imported honey of very low quality. The aim of this research paper was to study consumer perception of honey quality based on sensory attributes such as taste, aroma, colour and consistency. The primary research comprised the sensory blind test conducted as a part of questionnaire survey at selected shopping mall and at university. Research sample reached 400 respondents living in the Nitra region between 18 and 70 years. Respondents tested sensory attributes of two samples. Sample A represented Slovak honey from a local beekeeper and sample B was honey purchased from selected supermarket with country of origin „blend of EU and non - EU honeys" and represented imported honey. Besides descriptive statistics, the following statistical tests were applied: Fisher's Exact Test, Chi-Square Test of Independence, Cramer´V coefficient and Mann-Whitney U test. Results showed significant differences in perception of honey quality across age cohorts. Respondents older than 40 years (Generation X and Babyboomers) evaluated better the local honey from a beekeeper (sample A) than younger generations (Generation Y and Generation Z). Imported honey from selected supermarket (sample B) obtained the best evaluation in case of colour in both age cohorts while sample A obtained it in terms of aroma. The majority of respondents in both age cohorts mostly decided their preference according to taste, however there exist some differences. While Generation X and Baby boomers took into consideration also aroma, the generations Y and Z considered consistency. More interesting observation appealed in case of aroma where more than 90% of respondents, who decided according to aroma, preferred sample A - local Slovak honey. According to physico-chemical analysis, both samples fulfilled standard of EU legislation, however better parameters were reached in sample A. All in all, better perception of honey quality through sensory attributes in older age cohorts could be caused by the deeper experience in honey consumption as well as due to the fact that younger cohorts consume more semiproducts and industrial food products characterised by intensive, sweet taste which could confuse their assessments.
La pluralité culturelle dans le nouveau constitutionalisme en Amérique Latine
Authors: Campos Deo
Published: October 2018

Résumé:

L'histoire constitutionnelle de l'Amérique latine est marquée par divers mouvements idéologiques. Ces mouvements ont laissé des traces indélébiles sur les textes constitutionnels des pays de la région. Au même temps, dans une large mesure, le constitutionnalisme d'Amérique latine se caractérise par une histoire conservatrice en matière de diversité culturelle, indéniable caractéristique de la région. Cependent, au cours des dernières décennies, il y a eu l'émergence d'un nouveau concept du constitutionnalisme. Ce concept est engagé à la grande diversité ethnique et culturelle de la région. Ce travail vise à raconter le phénomène de la nouvelle constitutionnalisme d'Amérique latine et son conséquent engagement à la diversité culturelle.

Mots-clés: Amérique Latine. Droit constitutionnel. Histoire constitutionnelle. Nouveau constitutionnalisme latino-américain. Pluralité culturelle. Théorie de la constitution.
Retos de la investigación como asignación académica en la UNAH
Authors: Contreras Mario Aristides
Published: October 2018

La investigación científica como una tarea académica, anteriormente llamada Carga Académica, ha sido evaluada y gobernada por la Dirección de Investigación Científica de la Universidad (DICU) desde 2012. Se debe aclarar que la DICU no otorga la tarea, solo evalúa metodológicamente y las normas sobre Asimismo, las propuestas dan seguimiento a las investigaciones aprobadas hasta las cuales están terminadas para controlar su calidad. En este sentido, es el Jefe del Departamento Académico al que pertenece el profesor, quien asigna la investigación como parte de sus responsabilidades académicas.
Pensando uma possível proposta filosófica a partir da filmografia de Denis Villeneuve
Authors: Reina Alessandro , Vieira Jr. Luiz Alberto
Published: October 2018

O presente artigo tem como objetivo investigar a proposta cinematográfica do diretor canadense em ascensão Denis Villeneuve, problematizando a sua abordagem fílmica e possível convergência filosófica no trabalho com temas de profundidade reflexiva em seus projetos mais recentes como Incendies (CAN-2010), Prisoners (CAN-2013), Enemy (CAN-2013), Arrival (CAN-2016) e Blade Runner 2049 (EUA-2017), sendo capazes de incursionar o espectador à experiência do filosofar a partir da construção do filme como uma forma de pensamento.
Existence, Uniqueness and C −Differentiability of Solutions in a Non-linear Model of Cancerous Tumor
Authors: Pascal Gershom Gossan D. , Gozo Yoro , Balé Bailly
Published: October 2018

In this paper, we prove the existence and uniqueness of the weak solution of a system of nonlinear equations involved in the mathematical modeling of cancer tumor growth with a non homogeneous divergence condition. We also present  a new concept of generalized differentiation of non linear operators : C-differentiability. Through this notion, we also prove the uniqueness and the C-differentiability of the solution when the system is perturbed by a certain number of parameters. Two results have been established. In the first one, differentiability is according to Fréchet. The proof is given uses the theorem of reciprocal functions in Banach spaces. First of all, we give the proof of strict differentiability of a direct mapping, according to Fréchet. In the second result, differentiability is understood in a weaker sense than that of Fréchet. For the proof we use Hadamard's theorem of small perturbations of Banach isomorphism of spaces as well as the notion of strict differentiability.
Lerend evalueren: navigeren tussen verantwoorden en leren
Authors: Folkert Rob , Verwoerd Lisa , Verwest Femke
Published: October 2018

Lerend evalueren: navigeren tussen verantwoorden en leren

Een lerende evaluatie combineert leren en verantwoorden. Deze methode past bij complexe beleidsopgaven, waar meerdere actoren en overheden bij betrokken zijn die een behoefte hebben om te leren van elkaars ervaringen. In de evaluatie van het Natuurpact is deze methode op nationale schaal voor het gedecentraliseerde natuurbeleid toegepast. Uit deze casus blijkt dat een succesvolle toepassing vraagt om een voortdurende en zorgvuldige aansluiting van het onderzoek op de beleidspraktijk. Dit is nodig voor het betrekken van en interactie met stakeholders, het combineren van leren en verantwoorden, de wetenschappelijke onafhankelijkheid, het bestuurlijk mandaat en de beheersbaarheid van het onderzoek.
De aard en aanpak van georganiseerde cybercrime
Authors: Odinot Geralda , de Poot Christianne , Verhoeven Maite
Published: October 2018

The effect of the internet on the structure of organized cybercrime. Findings from an international empirical study

Worldwide, the digitalization of society is proceeding rapidly and this brings new forms of crime. The threats arising from different types of cybercrime are real and constantly evolving, as the internet with its anonymity and borderless reach, provides new opportunities for criminal activities. This article describes some results from an international empirical study aimed to gather more insight on the link between cybercrime and organized crime as well as on the question whether cybercrime is organized. It shows how cybercriminals cooperate with each other and what this organization structure looks like.
Criminele geldstromen en ICT: over innovatieve werkwijzen, oude zekerheden en nieuwe flessenhalzen
Authors: Kruisbergen Edwin , Leukfeldt Rutger , Kleemans Edward , Roks Robby
Published: October 2018

Criminal money flows and IT. On innovative modi operandi, old certainties, and new bottlenecks

In this article we analyze how organized crime offenders use IT to handle their money flows. How and to what extent do offenders use IT-facilitated possibilities, such as bitcoin, to launder their money? The empirical data consist of thirty large-scale police investigations. These thirty cases are part of the Organized Crime Monitor, an ongoing research project into the nature of organized crime in the Netherlands. One of the most striking findings is the fact that cash is still king – even for online drug dealers who get paid in digital currencies.
Uit de schaduw
Authors: Verburgh Thijmen , Smits Eefje , van Wegberg Rolf
Published: October 2018

Out of the shadow. Opportunities for researchers in studying dark markets

In this article the authors present the lessons learned from previous research efforts into dark markets. First the important features of dark markets are discussed, i.e. anonymity and trust, as well as the question how data on dark markets can be collected. Next, the authors illustrate how this data can be used to study the phenomenon of dark markets itself as well as the impact of police interventions on dark markets.
Facebookvrienden worden met de verdachte
Authors: Oerlemans Jan-Jaap
Published: October 2018

Befriending a criminal suspect on Facebook. Undercover powers on the Internet

This article investigates which online undercover investigative methods are applied in practice and how they fit in the Dutch legal framework. In particular, the three special investigative powers of a pseudo purchase, systematic information gathering and infiltration are examined. Investigative powers cannot be applied unilaterally (across state borders). When law enforcement officials cannot reasonably determine the location of the suspect, the online unilateral application of undercover investigative powers is allowed. However, there is still a risk that diplomatic tensions arise with the involved state. States should agree in treaties under which circumstances cross-border online undercover operations are allowed.
Nieuwe online opsporingsbevoegdheden en het recht op privacy
Authors: Custers Bart
Published: October 2018

New investigative powers and the right to privacy. An analysis of the Dutch Cybercrime III Act

In 2018 the Dutch parliament accepted new cybercrime legislation (the Cybercrime III Act) that creates several new online criminal offences and gives law enforcement agencies new investigative powers on the Internet. This article describes the background of Dutch cybercrime legislation and the contents of the Cybercrime III Act. The newly introduced cybercrimes are discussed as well as the new investigative competences. Particularly the legitimacy and the necessity of the investigative power of the police to hack computer systems of suspects may significantly interfere with the right to privacy.
Teorie principála a agenta a její využití při popisu vztahu volič–zástupce
Authors: Pospíšilová Jaroslava
Published: October 2018

This review article is focused on the rising framework of principal-agent analysis in political science. It aims to map the most influential studies and answer the question of whether this concept is adequate to describe the quality of the relationship between voters and their representatives. It is obvious that using the principal-agent framework leads to oversimplification. The economic theory of democracy is not a new model; nevertheless, using the game theoretic approach requires several adjustments. The adaptation of the main premises of the concept to the political reality should open new research questions with respect to the voter–elected officials relationship. Most principal–agent studies in empirical political science are focused on all links in the delegation chain but the first one. In my opinion, the link between voters and their representatives in a democracy is the fundamental one. Describing it using the tools of principal-agent theory could help scholars better understand current changes in the structure of political parties and voter behaviour.
Ship Hydrodynamics in Confined Waterways
Authors: Yuan Zhi-Ming
Published: October 2018

The hydrodynamic performance of a vessel is highly dependent on its maneuvering waterways. The existence of the banks and bottom, as well as the presence of the other vessels, could have a significant influence on a ship's hydrodynamic behavior. In confined waterways, many researchers suspect the applicability of the classical potential flow method because of its nonviscous and irrotational assumption. The main objective of the present article is to improve and develop the boundary value problem (BVP) of a potential flow method and validate its feasibility in predicting the hydrodynamic behavior of ships advancing in confined waterways. The methodology used in the present study is a 3D boundary element method based on a Rankine-type Green function. The numerical simulations are performed by using the in-house developed multibody hydrodynamic interaction program MHydro. The waves and forces (or moments) are calculated when ships are maneuvering in shallow and narrow channels, when ships are entering locks, or when two ships are encountering or passing each other. These calculations are compared with the benchmark test data published in MASHCON, and the published computational fluid dynamics results. It has been found that the free-surface elevation, lateral force, and roll moment can be well predicted in ship-bank and ship-bottom problems. However, the potential flow solver fails to predict the sign of the yaw moment because of the cross-flow effect. When a ship is entering a lock, the return-flow effect has to be considered. By adding a proper return-flow velocity to the BVP, the modified potential flow solver could predict the resistance and lateral forces very well. However, it fails to predict the yaw moment because of the flow separation at the lock entrance. The potential flow method is very reliable in predicting the ship-ship problem. The resistance and lateral force, as well as the yaw moment, can be predicted well by using the potential flow method.
Humanités numériques ou computationnelles
Authors: Meunier Jean-Guy
Published: October 2018

S’inscrivant dans l’univers des technologies informatiques, les humanités dites
numériques se présentent comme un nouveau programme de recherche. Le vrai défi de ce
programme de recherche ne sera cependant pas dans le traitement numérique qu’il veut
appliquer aux objets et opérations des humanités mais dans la modélisation
computationnelle qu’il doit leur appliquer. Malheureusement l’utilisation du concept
de numérique masque la grand complexité de cette tâche de modélisation qui, elle,
devra marier des fonctions computationnelles avec des fonctions interprétatives.
La Patagonie sans barrages
Authors: Sandoval Hernán , Gac Pierre-Raphaël , Belmar Javiera
Published: October 2018

Depuis la fondation de Patagonia sin Represas (Patagonie sans barrages) en 2007,
association créée par Hernán Sandoval, Président de l’ONG Chile Ambiente, ancien Ambassadeur
en France et actuel Doyen de l’Universidad de las Américas à Santiago, afin de s'opposer à
la dévastation de la Patagonie par les multinationales de l'électricité, une véritable
conscience écologiste s'est développée au Chili. Grâce aussi à l'appui international -dont
celui de Sens Public- les Chiliens ont réussi à arrêter le projet HydroAysén qui prévoyait
la construction d'immenses barrages destinés à piller l'un des réservoirs d'eau douce le
plus important de la planète. Le nouveau gouvernement de Michelle Bachelet, récemment élue
en battant pour la deuxième fois les néo-pinochétistes de l'ex-président Piñera, affirme que
le projet HydroAysén n'est pas viable en l'état. La lutte des écologistes continue car,
comme Hernán Sandoval le souligne dans notre entretien, « le capital est prêt à patienter
pendant des années pour arriver à ses fins... ».
La Patagonia sin represas
Authors: Sandoval Hernán , Gac Pierre-Raphaël , Belmar Javiera
Published: October 2018

Tras la fundación de Patagonia sin Represas en 2007, asociación creada por Hernán
Sandoval (ex embajador en Francia, Presidente de la ONG Chile Ambiente y decano de la
Universidad de las Américas) para oponerse a la devastación de la Patagonia chilena por las
multinacionales de la electricidad, una verdadera conciencia ecológica se ha desarrollado en
Chile. Gracias también al apoyo internacional, en el cual ha participado Sens Public, los
chilenos han conseguido detener el proyecto HydroAysén, que implicaba la construcción de
inmensas represas destinadas a rapiñar una de las reservas de agua dulce más importantes del
planeta. El nuevo gobierno de Michelle Bachelet, quien acaba de derrotar por segunda vez a
los neo-pinochetistas del ahora ex-presidente Piñera, afirma que el proyecto no es
realizable en su estado actual ni viable políticamente. Sin embargo la lucha de los
ecologistas continúa pues, como Hernán Sandoval previene, « el capital está preparado para
esperar durante años para imponerse… ».
Creolization of politics, Politics of Creolization: thinking of an “unthought” in the work of Edouard Glissant
Authors: Dorismond Edelyn , Lingeswaran Amudha
Published: October 2018

Cet article cherche à montrer en quoi la créolisation laisse pendante la question de l’organisation politique d’une société créole ou du monde créole à venir. C’est dire qu’il y a là quelque chose d’heuristique que suscite la pensée de Glissant. Nous ne ferons qu’esquisser les problèmes d’ordre politique que fait naître la créolisation. Nous ne nous préoccuperons pas de répondre aux questions qui seront formulées. L’intérêt de ce travail est dans le fait unique de souligner l’impasse politique à laquelle nous conduit la pensée glissantienne de la créolisation au regard de certains concepts de la politique qui, quoiqu’on dise, ne cesse d’être opérationnelle : ceux de l’Etat, de l’Etat-Nation, de la Terre ou de la Patrie, ceux de la Culture et de l’identité. Quant à cette dernière, on dit qu’elle ne se commande pas ; c’est dire aussi que sa vie est dure, sa durée est vitale.
Attribution of non-ClinicalTrials.gov registries among WHO International Clinical Trials Registry Platform-registered trials from 2014 to 2018: A protocol for a meta-epidemiological study
Authors: Banno Masahiro , Tsujimoto Yasushi , Kataoka Yuki
Published: October 2018

Background. The attribution of non-ClinicalTrials.gov registries among registered trials of the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) had increased until 2013. However, the attribution after 2013 is unknown. Moreover, no study has investigated the usage of non-ClinicalTrials.gov registries after 2015 or compared the characteristics of trials under non-ClinicalTrials.gov and ClinicalTrials.gov registries. Methods. This will be a meta-epidemiological study. It will include all trials registered on the ICTRP from January 1, 2014, to December 31, 2018. First, we will describe the total attribution of non-ClinicalTrials.gov registries among the ICTRP-registered trials for each year and each registry worldwide. Second, we will compare the recruitment status, target sample size, study type, study design, countries, prospective registration, funding, and study phase of the trials on ClinicalTrials.gov and other registries from 2014 to 2018. Third, we will report on the distribution of primary registries of trials from the top five countries in order of the quantity of registered trials on the ICTRP. Ethics & Dissemination. Ethics approval is not required for this study. This protocol has been registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR). The findings will be published in a peer-reviewed journal and may be presented at conferences. Trial Registration Number. UMIN000034401
Nephrology/hypertension/fluid and electrolyte disorders
Authors: Slick Gary L.
Published: October 2018

The following annotated bibliography has been developed for the purpose of providing to primary care physicians a handy source of review articles and major studies in the the field of nephrology, hypertension, and fluid and electrolyte disorders. Almost all of the articles are review articles of clinical topics that would be of interest to the practicing physician. JAOA will be publishing additional annotated bibliographies in various fields of internal medicine over the next several months. The second in this series will appear in a forthcoming issue of THE JOURNAL.
Research secures the future of osteopathic medicine: Part 2: Readdressing the function and structure of colleges of osteopathic medicine
Authors: Papa Frank J.
Published: October 2018

Many problems exist within the contemporary medical education process in general and the osteopathic medical profession in particular. Part 2 of this series suggests that the single greatest impediment to solving these problems is an institutional infrastructure that is not congruent with the institution's functions, as defined in its mission statement. (This mission statement generally entails two primary goals: education and research.) Two major divisions within the core's infrastructure are suggested: medical education and medical research. By restructuring their infrastructure, colleges of osteopathic medicine can more effectively address and support their primary functions of education and research.
Acute mastocytosis: A potential dermatologic emergency
Authors: Kamajian George , Felix Jose
Published: October 2018

A comatose patient arrived at the emergency room with apnea and in shock after a grand mal seizure. A maculopapular rash, not initially observed, led to a diagnosis of cutaneous mastocytosis. Degranulation of the mast cells with massive histamine release had resulted in cardiovascular collapse. The authors follow a detailed report of this case history with a discussion of the diagnosis and treatment of the acute systemic stage of this potentially life-threatening illness.
Effect of thermal oxidation temperatures on the phase evolution and photocatalytic property of tungsten-doped TiO2 thin film
Authors: Yeh Ming-Yuan , Lee Ping-Yuan , Shang Jie-Ting , Lee Ying-Chieh
Published: October 2018

Tungsten-doped titanium dioxide (W-TiO2) thin films were successfully prepared on glass substrates by sputtering thermally oxidized W-doped titanium films in air. Tungsten-doped titanium films were deposited using a DC and RF magnetron cosputtering system. The effects of annealing treatment and W content on the W-TiO2 film microstructure were investigated. The crystalline structures, morphological features, and photocatalytic activity of the annealed W-TiO2 films were systematically studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and ultraviolet spectrophotometry. The results indicated that annealing at 550 °C clearly induced the formation of an anatase and rutile phase mixture in the 5.5 at. % W-TiO2 films, which directly affected photocatalytic activity. The W-TiO2 films showed good photocatalytic activity under UV-light irradiation, with a higher rate of methylene blue dye degradation than in the case of undoped TiO2.
Size-dependent functional response ofXenopus laevisfeeding on mosquito larvae
Authors: Thorp Corey J. , Alexander Mhairi E. , Vonesh James R. , Measey John
Published: October 2018

Predators can play an important role in regulating prey abundance and diversity, determining food web structure and function, and contributing to important ecosystem services, including the regulation of agricultural pests and disease vectors. Thus, the ability to predict predator impact on prey is an important goal in ecology. Often, predators of the same species are assumed to be functionally equivalent, despite considerable individual variation in predator traits known to be important for shaping predator–prey interactions, like body size. This assumption may greatly oversimplify our understanding of within-species functional diversity and undermine our ability to predict predator effects on prey. Here, we examine the degree to which predator–prey interactions are functionally homogenous across a natural range of predator body sizes. Specifically, we quantify the size-dependence of the functional response of African clawed frogs (Xenopus laevis) preying on mosquito larvae (Culex pipiens). Three size classes of predators, small (15–30 mm snout-vent length), medium (50–60 mm) and large (105–120 mm), were presented with five densities of prey to determine functional response type and to estimate search efficiency and handling time parameters generated from the models. The results of mesocosm experiments showed that type of functional response ofX. laevischanged with size: small predators exhibited a Type II response, while medium and large predators exhibited Type III responses. Functional response data showed an inversely proportional relationship between predator attack rate and predator size. Small and medium predators had highest and lowest handling time, respectively. The change in functional response with the size of predator suggests that predators with overlapping cohorts may have a dynamic impact on prey populations. Therefore, predicting the functional response of a single size-matched predator in an experiment may misrepresent the predator’s potential impact on a prey population.
Mechanical Characterization of hiPSC‐Derived Cardiac Tissues for Quality Control
Authors: Park Seungman , Lui Cecillia , Jung Wei‐Hung , Maity Debonil , Ong Chin Siang , Bush Joshua , Maruthamuthu Venkat , Hibino Narutoshi , Chen Yun
Published: October 2018

Heart disease is one of the leading death causes in developed countries. To facilitate heart rehabilitation, engineered cardiac implantation has emerged as a promising alternative to organ transplantation. Currently there is no quantitative standard to ensure the safety and functionality of the engineered cardiac tissues intended for clinical uses. In anticipation of the clinical application of the engineered cardiac tissues to heart disease patients, a suite of methods is assembled to evaluate the mechanical characteristics critical to cardiac functions, including contractility, viscoelasticity, and dynamic stress distribution. As a proof of concept, 3D bioprinted cardiac tissues derived from human induced pluripotent stem cells are tested. First, the engineered cardiac tissues labeled with particles are recorded and tracked to determine spatially and temporally variable contraction forces. Viscoelastic properties are measured using magnetic tweezers. The results are used to compute 3D force and stress distribution over the engineered tissue by finite element method. In summary, a framework is developed to assess clinical‐grade engineered cardiac tissues and determine the appropriate value ranges suitable for implantation. The results relating contractility, intrinsic mechanical properties, and stress distribution in the engineered tissue, can also inform better design for future fabrication of engineered tissues.
Microstructure and Properties of Porous SiC Ceramics Modified by CVI‐SiC Nanowires
Authors: Nan Beiya , Liu Yongsheng , You Qiangwei , Wan Jiajia , Shen Zhijian , Li Hongxia , Yuan Bo , Cheng Laifei , Wang Gang
Published: October 2018

Sintered porous SiC ceramics are modified with SiC nanowires prepared via chemical vapor infiltration (CVI). SiC nanowires are successfully grown within sintered porous SiC ceramics following vapor–liquid–solid growth. The diameter of the SiC nanowires is in the range of 200 nm–1 μm, and first decreases with increasing input gas ratio (α = 50, 60, 70, and 80) and increases thereafter. The diameter of the nanowires decreases from the surface to the interior areas of the porous SiC ceramics. SiC nanowires effectively improve the mechanical properties of the porous SiC ceramics, and sample Ni‐50 has the highest flexural strength of 33.91 MPa and fracture toughness of 0.79 MPa · m1/2, which increases by 90.4% and 49.1% compared to an unmodified sample, respectively. Additionally, the presence of SiC nanowires leads to porous SiC ceramics with altered porosity and microstructure, and higher thermal conductivity. The porous SiC ceramics modified by CVI SiC nanowires satisfy the requirements of gas filtration applications and the pressure drop increases with decreasing apparent porosity. The porous SiC ceramics modified with CVI SiC nanowire has higher permeability than those resulting from the introduction of CVI‐SiC matrix or CVD‐SiC coating into porous SiC ceramics.
Low Resistance–Integrated All‐Solid‐State Battery Achieved by Li7La3Zr2O12 Nanowire Upgrading Polyethylene Oxide (PEO) Composite Electrolyte and PEO Cathode Binder
Authors: Wan Zipei , Lei Danni , Yang Wei , Liu Cheng , Shi Kai , Hao Xiaoge , Shen Lu , Lv Wei , Li Baohua , Yang Quan‐Hong , Kang Feiyu , He Yan‐Bing
Published: October 2018

All‐solid‐state lithium metal battery is the most promising next‐generation energy storage device. However, the low ionic conductivity of solid electrolytes and high interfacial impedance with electrode are the main factors to limit the development of all‐solid‐state batteries. In this work, a low resistance–integrated all‐solid‐state battery is designed with excellent electrochemical performance that applies the polyethylene oxide (PEO) with lithium bis(trifluoromethylsulphonyl)imide as both binder of cathode and matrix of composite electrolyte embedded with Li7La3Zr2O12 (LLZO) nanowires (PLLN). The PEO in cathode and PLLN are fused at high temperature to form an integrated all‐solid‐state battery structure, which effectively strengthens the interface compatibility and stability between cathode and PLLN to guarantee high efficient ion transportation during long cycling. The LLZO nanowires uniformly distributed in PLLN can increase the ionic conductivity and mechanical strength of composite electrolyte efficiently, which induces the uniform deposition of lithium metal, thereby suppressing the lithium dendrite growth. The Li symmetric cells using PLLN can stably cycle for 1000 h without short circuit at 60 °C. The integrated LiFePO4/PLLN/Li batteries show excellent cycling stability at both 60 and 45 °C. The study proposed a novel and robust battery structure with outstanding electrochemical properties.
Isolation of Silk Mesostructures for Electronic and Environmental Applications
Authors: Zheng Ke , Zhong Jiajia , Qi Zeming , Ling Shengjie , Kaplan David L.
Published: October 2018

A ubiquitous feature of natural silk fibers is the presence of well‐organized mesostructures, including microfibrils, nanofibrils, and nanoparticles. These mesoscale building blocks are typically well organized into sophisticated arrangements and contribute robust mechanical performance and functions as part of natural silk fibers. However, it remains a major challenge to directly isolate these mesostructures for engineering applications. Here, an environmentally friendly and scalable “partial dissolution and physical dispersion” strategy is developed to exfoliate silk fibers into different mesostructures, including microfibrils, nanofibrils, nanorods, and nanoparticles. On the basis of the advantages of these mesosilks in tunable sizes, sharp size distributions, high modulus, excellent redispersibility, as well as versatile processability, the applications of these mesosilks in electronic and environmental fields are further explored, including water treatment, recycling organic solvent, paper sensors, and nanofertilizers. These explorations open a new avenue for silk fiber applications while also providing a pathway to help address critical issues in electronic and environmental fields.
PEGylation Regulates Self‐Assembled Small‐Molecule Dye–Based Probes from Single Molecule to Nanoparticle Size for Multifunctional NIR‐II Bioimaging
Authors: Ding Feng , Li Chonglu , Xu Yuling , Li Jiaxin , Li Haibing , Yang Guangfu , Sun Yao
Published: October 2018

To date, small‐molecule dye–based probes have been at the forefront of research in biomedical imaging, especially in the second near‐infrared (NIR‐II) window (1.0–1.7 µm). However, how to precisely regulate the synthesized size of NIR‐II organic dye–based probes remains challenging. Moreover, systematic studies on whether the size of NIR‐II probes affects optical/pharmacokinetic properties are still rare. Here, an ingenious PEGylation strategy is developed to regulate the self‐assembly size of organic dye–based (CH1055 scaffold) NIR‐II probes (SCH1–SCH4) from nanoparticles to the single molecule, and the relationship between their size and chemical/physical properties is thoroughly investigated. Based on their own merits, nanoprobe SCH1 (≈170 nm), with outstanding fluorescent brightness (quantum yield ≈0.14%), performs accurate tracing of the lymphatic system as well as identification of vessel networks in mice brains with excellent signal‐to‐background ratio images. Meanwhile, rapidly excreted SCH4, showing fast and high passive liver tumor uptake and promising tumor/normal tissue ratios (>7), is capable of facilitating precise image‐guided tumor surgery, and also demonstrates the first example of the assessment of liver fibrosis in the NIR‐II window.
Spray‐On Reduced Graphene Oxide‐Poly(vinyl alcohol) Supercapacitors for Flexible Energy and Power
Authors: De Souvik , Purcell Caroline , Murley Joshua , Flouda Paraskevi , Shah Smit , Green Micah , Lutkenhaus Jodie
Published: October 2018

Flexible and mechanically robust energy storage devices, such as capacitors, are future enablers of the next generation of structural energy and power, flexible electronics, and biometrics. These concepts require that the capacitor be seamlessly integrated into the device in a scalable process, while still maintaining mechanical and electrochemical properties. The challenge is that ease‐of‐processing, mechanical, and electrochemical properties are not mutually exclusive. Spraying allows for fast manufacture, but producing an ink amenable to spraying is challenging because of aggregation of the electroactive materials in the dispersion, resulting in poor performance. Here, sprayable, flexible supercapacitor electrodes are demonstrated containing reduced graphene oxide (rGO), poly(vinyl alcohol) (PVA), and carbon black achieved via high‐throughput air‐brushing process from aqueous media. The spray processing, mechanical properties, and electrochemical performance of various compositions of rGO, PVA, and carbon black are explored. rGO sheets provide capacitive energy storage, PVA facilitates air‐brushing, and carbon black bridges rGO sheets to form electronic pathways. Due to the good combination of mechanical and electrochemical properties, a flexible supercapacitor shows steady capacitance retention after several bending cycles. This spray‐on three‐component composite electrode balances electrochemical and mechanical properties, which is otherwise difficult to realize for compact brick and mortar structures, especially from airbrushing.
Highly Conductive Polydimethylsiloxane/Carbon Nanofiber Composites for Flexible Sensor Applications
Authors: Chowdhury Shoieb A. , Saha Mrinal C. , Patterson Steven , Robison Thomas , Liu Yingtao
Published: October 2018

A polydimethylsiloxane (PDMS)/carbon nanofiber (CNF) nanocomposite with piezoresistive sensing function is presented. Excellent electrical conductivity is achieved by dispersing the CNFs into PDMS. A facile, low cost, and scalable fabrication procedure allows the sensors to be made in different shapes. The piezoresistive sensors show repeatable response up to 30% tensile strain. In addition, the characterization of sensing mechanism using an in situ mechanical testing system within a scanning electron microscope reveals the reorganization of CNF network by varying fiber alignment and interfiber distance in the nanocomposites under tensile load. To validate the wearable sensing capability, nanocomposite straps are employed to monitor the finger motions under various bending speed and holding time. Two different shapes of compressive sensors, including cylinder and truncated cone, are tested in compression strain as low as 3%, with gauge factors of 18.3 and 6.3, respectively. In addition, the sensing capability is independent of the applied strain rates and is highly repeatable in 1000 cycles under compression. Finally, the developed nanocomposites are made into sensor arrays for pressure sensing ranging from 35 to 690 kPa. The versatility and ease of fabrication of the reported nanocomposites can bridge the current challenge between performance and applicability of flexible sensors.
Engineering Precision Medicine
Authors: Sun Wujin , Lee Junmin , Zhang Shiming , Benyshek Cole , Dokmeci Mehmet R. , Khademhosseini Ali
Published: October 2018

Advances in genomic sequencing and bioinformatics have led to the prospect of precision medicine where therapeutics can be advised by the genetic background of individuals. For example, mapping cancer genomics has revealed numerous genes that affect the therapeutic outcome of a drug. Through materials and cell engineering, many opportunities exist for engineers to contribute to precision medicine, such as engineering biosensors for diagnosis and health status monitoring, developing smart formulations for the controlled release of drugs, programming immune cells for targeted cancer therapy, differentiating pluripotent stem cells into desired lineages, fabricating bioscaffolds that support cell growth, or constructing “organs‐on‐chips” that can screen the effects of drugs. Collective engineering efforts will help transform precision medicine into a more personalized and effective healthcare approach. As continuous progress is made in engineering techniques, more tools will be available to fully realize precision medicine's potential.
An in vivo study of the pharmacological activities of a methanolic acetate fraction of Pistia stratiotes L.: An ethno‐medicinal plant used in Bangladesh
Authors: Hussain Md. Saddam , Ibrahim Md. , Hasan Md. Murad , Aziz Mohammad Tarek , Suchi Suzia Akter , Uddin Md. Giash
Published: October 2018

Background

The present study covered an assessment of methanolic acetate fractions of Pistia stratiotes, commonly known as water lettuce, for analgesic, anti‐inflammatory, and CNS depressant activities.

Methods

The methanol acetate fractions were extracted from Pistia stratiotes and administered to the experimental animals as 200 and 400 mg/kg doses to determine the effect on acetic acid‐induced writhing and formalin‐induced licking and biting, for the assessment of analgesic activity. The anti‐inflammatory assay was done using the carrageenan‐induced hind paw edema method, while assessment of CNS depressant activity was done using the open field and hole cross tests. The effects were compared to standard reference drugs.

Results

At both doses (200 and 400 mg/kg body weight), the methanolic acetate extract of P. stratiotes showed significant analgesic action (P < 0.05) against acetic acid‐induced writhing. The extract was also found to give significant protection against licking and biting at both doses. The methanolic acetate extract of P. stratiotes showed a significant (P < 0.05) anti‐inflammatory effect from 0 minutes up to 3 hours in the carrageenan‐induced paw edema test. In the CNS depressant assay, the methanolic acetate extract showed significant (P < 0.05) depressant activity at both doses from 30 to 120 minutes in both the hole cross and open field tests.

Conclusion

Thus we can conclude that P. stratiotes extracts have significant analgesic, anti‐inflammatory, and CNS depressant activity, compared to standard compounds, in an animal model.
Palladium‐Catalyzed Decarbonylative Borylation of Carboxylic Acids: Tuning Reaction Selectivity by Computation
Authors: Liu Chengwei , Ji Chong‐Lei , Hong Xin , Szostak Michal
Published: October 2018

Decarbonylative borylation of carboxylic acids is reported. Carbon electrophiles are generated directly after reagent‐enabled decarbonylation of the in situ accessible sterically‐hindered acyl derivative of a carboxylic acid under catalyst controlled conditions. The scope and the potential impact of this method are demonstrated in the selective borylation of a variety of aromatics (>50 examples). This strategy was used in the late‐stage derivatization of pharmaceuticals and natural products. Computations reveal the mechanistic details of the unprecedented C−O bond activation of carboxylic acids. By circumventing the challenging decarboxylation, this strategy provides a general synthetic platform to access arylpalladium species for a wide array of bond formations from abundant carboxylic acids. The study shows a powerful combination of experiment and computation to predict decarbonylation selectivity.
Covalent Organic Frameworks with Chirality Enriched by Biomolecules for Efficient Chiral Separation
Authors: Zhang Sainan , Zheng Yunlong , An Hongde , Aguila Briana , Yang Cheng‐Xiong , Dong Yueyue , Xie Wei , Cheng Peng , Zhang Zhenjie , Chen Yao , Ma Shengqian
Published: October 2018

The separation of racemic compounds is important in many fields, such as pharmacology and biology. Taking advantage of the intrinsically strong chiral environment and specific interactions featured by biomolecules, here we contribute a general strategy is developed to enrich chirality into covalent organic frameworks (COFs) by covalently immobilizing a series of biomolecules (amino acids, peptides, enzymes) into achiral COFs. Inheriting the strong chirality and specific interactions from the immobilized biomolecules, the afforded biomolecules⊂COFs serve as versatile and highly efficient chiral stationary phases towards various racemates in both normal and reverse phase of high‐performance liquid chromatography (HPLC). The different interactions between enzyme secondary structure and racemates were revealed by surface‐enhanced Raman scattering studies, accounting for the observed chiral separation capacity of enzymes⊂COFs.
Facile fabrication of BUC‐21/g‐C3N4 composites and their enhanced photocatalytic Cr(VI) reduction performances under simulated sunlight
Authors: Yi Xiao‐Hong , Wang Fu‐Xue , Du Xue‐Dong , Wang Peng , Wang Chong‐Chen
Published: October 2018

A series of BUC‐21/g‐C3N4 composites were facilely fabricated from two‐dimensional metal–organic framework BUC‐21 and two‐dimensional metal‐free polymer semiconductor graphitic carbon nitride (g‐C3N4) through ball‐milling, and characterized via powder X‐ray diffraction, Fourier transform infrared spectrometry, thermogravimetric analysis, transmission electron microscopy, and UV–visible diffuse reflectance, X‐ray photoelectron and photoluminescence emission spectrometry. The photocatalytic activities of B100G100 (weight ratio of BUC‐21 to g‐C3N4 being 1:1) towards Cr(VI) reduction were investigated upon the irradiation of simulated sunlight and real sunlight, in which the influences of various organic compounds (tartaric acid, citric acid and oxalic acid) as hole scavengers, pH values (2, 3, 4, 5, 6, 7 and 8) and foreign ions (ions in tap water and real surface water) were also investigated. The results revealed that B100G100 exhibited more outstanding photocatalytic Cr(VI) reduction than individual BUC‐21 and g‐C3N4, resulting from enhanced separation of photogenerated electrons and holes, which were confirmed via both photoluminescence emission and electrochemical determination. The B100G100 composite exhibited good reusability and stability after several experimental runs. Also, the corresponding mechanism of photocatalytic reaction was proposed.