bluuebunny/crossref_metadata_2025 huggingface dataset:
Uma abordagem etnomatemática para o Currículo Trivium
Authors: Rosa Milton , Raimundi Marcos Paulo Vieira
Published: February 2019

Um dos principais objetivos da Educação Matemática é buscar o desenvolvimento de um processo educacional que possibilite a aquisição e a utilização, pelos alunos, de instrumentos comunicativos, analíticos e materiais essenciais para o pleno exercício dos direitos e deveres intrínsecos à cidadania. Este artigo teórico visa ressaltar que esses instrumentos estão relacionados com a proposição do Currículo Trivium para a Matemática, no qual são considerados três componentes: a) a literacia, que está relacionada com a funcionalidade dos indivíduos na sociedade; b) a materacia, que está relacionada com o entendimento de situações inovadoras desenvolvidas por indivíduos criativos; e c) a tecnoracia, que está relacionada com a utilização astuta dos materiais disponíveis em contextos culturais diversos.Palavras-chave: Currículo Trivium. Etnomatemática. Literacia. Materacia. Tecnoracia.An ethnomathematical approach to the Trivium CurriculumOne of the main objectives of Mathematics Education is to seek the development of an educational process that enables students to acquire and use communicative, analytical, and material instruments which are essential for the exercise of rights and duties intrinsic to citizenship. This theoretical article aims to emphasize that these instruments are related to the proposition of the Trivium Curriculum for Mathematics, in which three components are considered: a) literacy, which is related to the functionality of individuals in society; b) matheracy, which is related to the understanding of innovative situations developed by creative individuals; and c) technoracy, which is related to the astute use of materials available in diverse cultural contexts.Keywords: Trivium Curriculum. Ethnomathematics. Literacy. Matheracy. Technoracy.Un abordaje etnomatemática para el Currículo TriviumUno de los principales objetivos de la Educación Matemática es buscar el desarrollo de un proceso educativo que haga posible la adquisición y la utilización por los alumnos de instrumentos comunicativos, analíticos y materiales esenciales para el pleno ejercicio de los derechos y deberes intrínsecos a la ciudadanía. Este artículo teórico apunta a resaltar que estos instrumentos están relacionados con la proposición del Currículo Trivium para las Matemáticas, en el cual se consideran tres componentes: a) la literacía, que está relacionada con la funcionalidad de los individuos en la sociedad; b) la materacía, que está relacionada con el entendimiento de situaciones innovadoras desarrolladas por individuos creativos; y c) la tecnoracía, que está relacionada con la utilización hábil de los materiales disponibles en contextos culturales diversos.Palabras clave: Currículo Trivium. Etnomatemáticas. Literacía. Materacía. Tecnoracía
Raciocínio visuoespacial: uma comparação entre a construção de um tambor de mão nativo americano e a geometria cirúrgica
Authors: Shockey Tod , Mitchell John Bear
Published: February 2019

Este artigo centra-se na construção de um tambor de mão por um fabricante de tambor nativo americano e na construção de uma anastomose por um cirurgião cardiovascular torácico. Nenhuma das atividades ocorrerram com instruções ou ilustrações escritas. Cada construção ocorreu através da sua capacidade de mover imagens e procedimentos mentais na ponta dos dedos com a utilização do raciocínio visuoespacial (Owens, 2015). Para o fabricante do tambor, o aprendizado ocorreu por meio da orientação, da observação e da prática. Cada um deles, o fabricante do tambor e o cirurgião, desenvolveu ricas habilidades de raciocínio espacial baseadas em relacionamentos. Para o fabricante de tambor, os relacionamentos têm a ver com a geometria do tambor e os seus componentes, assim como as relações de geometria cirúrgica existem na sala de operação. Para a resistência do tambor, as tensões são sentidas com a ponta dos dedos, a mesma experiência do cirurgião. Paralelos são destacados entre essas atividades aparentemente não relacionadas com a discussão de possíveis implicações para a Educação Matemática.
A participação de professores na elaboração de tarefas matemáticas em um trabalho colaborativo
Authors: Costa Wedeson Oliveira , Oliveira Andreia Maria Pereira de
Published: February 2019

Neste artigo, apresentamos um trabalho desenvolvido com o objetivo de identificar e analisar como professores participam da elaboração de tarefas matemáticas no projeto Observatório da Educação Matemática (OEM-Bahia). A pesquisa foi de natureza qualitativa e os dados foram coletados por meio da observação de reuniões e da realização de entrevistas com professores responsáveis pela implementação das tarefas. Os resultados apontam que os professores participam da elaboração de tarefas atendendo aos objetivos comuns do grupo e compartilhando modos de elaborar questões investigativas ou exploratórias. Essas formas de participar têm relação com o empreendimento conjunto estabelecido pelo grupo para a elaboração das tarefas e com o repertório compartilhado entre os membros do grupo, que possibilitou indícios de mudanças nas práticas em que os professores participam.
“No Man Hath Dared to Write This Thing as Yet”: Tradition and the Individual Talent of Ezra Pound
Authors: ŞENLEN GÜVENÇ Sıla
Published: February 2019

Yazarın konumu ve rolünü belirlerken bir yaratıcıdan tutun da geçmiş geleneğin bir parçası ve ürünü olarak değerlendiren, yazar ile metin arasındaki ilişkiyi tanımlayan nice kuram mevcuttur. Şiire birçok yenilik getiren ve katkıda bulunan modernist şair Ezra Pound'un, hem İngiliz hem de Amerikan şiirine büyük etkisi olmuştur. T. S. Eliot “Tradition and the Individual Talent” (“Gelenek ve Bireysel Yetenek”) başlıklı çalışması ile geçmiş geleneğe ve şairlere büyük önem atfetmesine karşın, kaleme aldığı 'yeni' çalışmalarıyla kendi bireysel otoritesini de ortaya koymaktadır. Pound, şiiri hakettiği mevkiye getirmeyi hedeflese de, bunu, kendini üstün bir konuma getirerek ve okuyucuya erişiyemeyecekleri yüksek standartlar oluşturarak, halk ile kendisi arasında bir 'entelektüel fark' yaratmaktadır. Bu çalışmanın amacı, Pound'un şiiri hak ettiği noktaya yükseltme arzusunun halkı göz ardı edip kısıtlı bir entelektüel kesime hitap etmesini ve dolayısıyla 'elitist' bir konum oluşturma çabasını ortaya koymaktır.
İtalyan Misyonerler Ulusal Yardım Derneği'nin Osmanlı Coğrafyasındaki İnşa Faaliyetleri Üzerine Bazı Düşünceler
Authors: İŞLER Didem
Published: February 2019

İtalyan Misyonerler Ulusal Yardım Derneği A.N.M.I. (Associazione Nazionale per Soccorrere i Missionari Italiani), 19-20.yüzyıllarda, Osmanlı coğrafyasında eğitim ve sağlık kuruluşları başta olmak üzere yardım kurumu niteliği taşıyan çok sayıda yapı inşa ettirmiştir. Osmanlı İmparatorluğu'nun çözülme sürecine denk gelen bu yapı faaliyetleri, kuşkusuz rastlantısal değildir. Bu bağlamda Osmanlı coğrafyasında ve tüm Orta Doğu'da faaliyet göstererek kent fiziğini dönüştürücü nitelikte etkiler bırakan bu unsur, siyaset, sosyoloji ve iktisat tarihi araştırmalarının yanı sıra mimarlık tarihi çalışmalarına da konu teşkil edecek boyutta bir yoğunluğa ve öneme sahiptir.
The Human–Animal Relation in Rousseau's Discourse on Inequality
Authors: Inston Kevin
Published: February 2019

The Discourse on Inequality disputes the human–animal hierarchy in its denunciation of social inequality as unnatural. Stripping away social artifice, it reveals a deep physical continuity between man and animals. As embodied creatures, they share mortality and vulnerability. Human animality does not, however, negate human difference. Man differs from animals through perfectibility: the freedom to change. That difference comes from the lack of any specifically human property, thereby challenging rather than confirming anthropocentric hierarchies. Any properties seen to distinguish man from animals are in fact improper, contingent and artificial. Human impropriety renders man always dependent on external relations for his development. Compassion, vital for a Rousseauian approach to animal ethics, allows man to experience this relationality, transporting him towards others as he identifies with their suffering as recalling the finitude and vulnerability shared by all creatures. For Rousseau, human difference, it is argued, enables rather than blocks identification with animality.
Deadly Mirrors: Animal Death in Tommaso Landolfi and Stefano D'Arrigo
Authors: Benvegnù Damiano
Published: February 2019

From Hegel to Heidegger and Agamben, modern Western philosophy has been haunted by how to think the connections between death, humanness and animality. This article explores how these connections have been represented by Italian writers Tommaso Landolfi (1908–79) and Stefano D'Arrigo (1919–92). Specifically, it investigates how the death of a nonhuman animal is portrayed in two works: ‘Mani’, a short story by Landolfi collected in his first book Il dialogo dei massimi sistemi (Dialogue on the Greater Harmonies) (1937), and D'Arrigo's massive novel Horcynus Orca (Horcynus Orca) (1975). Both ‘Mani’ and Horcynus Orca display how the fictional representation of the death of a nonhuman animal challenges any philosophical positions of human superiority and establishes instead animality as the unheimlich mirror of the human condition. In fact, in both stories, the animal — a mouse and a killer whale, respectively — do die and their deaths represent a mise en abyme that both arrests the human narrative and sparks a moment of acute ontological recognition.
Application of Duration Measure in Quantifying the Sensitivity of Project Returns to Changes in Discount Rates
Authors: Yousefi Vahidreza , Yakhchali Siamak Haji , Tamošaitienė Jolanta
Published: February 2019

In this research, the concept of Duration with a new application in project management has been defined. The Duration of each project provides the project manager with a combined measure containing concepts of return, cost and time of the project. Further in this article, the changes in project return, based on different assumptions such as discount rate, have been examined. To examine the effect of the changes in these factors, the Monte Carlo simulation has been used. The relationship between these factors is nonlinear which reflects the great importance of investment on appropriate risk management systems. The data from a set of construction projects have been used in order to verify the results of this study. Similar relationships can be expected to exist in other industries as well.
Manufacturing Process of High Performance–Low Cost Composite Structures for Light Sport Aircrafts
Authors: Torres Mauricio , Piedra Saúl , Ledesma Saúl , A. Escalante-Velázquez Carlos , Angelucci Giovanni
Published: February 2019

This work describes the technological and scientific efforts on designing, manufacturing and testing validation for high performance-low cost composite structures for Light Sport Aircrafts (LSA). A Mexican initiative to conceive, manufacture and assembly a Light Sport Aircraft has been developed by using Computational Fluid Dynamics (CFD), Finite Element Analysis (FEA) and Liquid Composite Manufacturing (LCM). These consolidated techniques are used to characterize novel approaches to manufacturing and assembly carbon-fiber based structural components. As large structures are manufactured via Vacuum Assisted Resin Infusion (VARI), impregnation strategies are studied to minimize inner flaws and also to improve the manufacturing time and surface quality of each component. The first case of study, to validate this methodology, involves non-structural components such as the cowling. Control surfaces (ailerons, rudder, elevator and flaps) have been manufactured, each of them having common issues but also unique challenges. As an example, a second case of study, the aileron main beam is analyzed. Furthermore, test portfolio will be developed with the goal to perform 1-to-1 scale mechanical tests for validation in compliance with ASTM standards.
Effect of Water Supply on Spectral Traits and Their Relationship with the Productivity of Sweet Corns
Authors: Nemeskéri Eszter , Molnár Krisztina , Rácz Csaba , Dobos Attila Csaba , Helyes Lajos
Published: February 2019

Three super-sweet corn hybrids (Zea mays L. convar. saccharata) with different ripening characteristics were grown in three water supplies (regularly irrigated, deficit-irrigated, and unirrigated) to examine the spectral reflectance at leaf and canopy levels, leaf area index (LAI) during the stage of development and their relationship with the yield and nutritional quality. Under unirrigated conditions, the plant’s height, diameter, and weight of ears per plants, as well as total carotenoid content of kernels, decreased, SPAD values of leaves, normalized vegetation differential index (NDVI) and LAI were low. The difference in SPAD and LAI was higher between the hybrids during the silking than the tasseling period under water deficiency. Under unirrigated dry conditions, no correlation was found between SPAD, NDVI, and yield. Using deficit irrigation, SPAD measured during tasseling correlated closely with the individual husked ear and the final yields as well as the sugar and carotene contents of kernels. Under this condition, NDVI did not correlate with the yield, but LAI was correlated with the yield and its carotene content. Under deficit irrigated conditions, the 46 to 49 range of SPAD measured during tasseling predicted 23.5 to 26.7 t ha−1 depending on the hybrid, but this range predicted a yield lower by 6.4 to 10.1% during silking.
Extracts from Microalga Chlorella sorokiniana Exert an Anti-Proliferative Effect and Modulate Cytokines in Sheep Peripheral Blood Mononuclear Cells
Authors: Ciliberti Maria , Albenzio Marzia , Francavilla Matteo , Neglia Gianluca , Esposito Luigi , Caroprese Mariangela
Published: February 2019

The objective of this experiment was to study the effects of the unsaponified fraction (UP), the acetylated unsaponified fraction (AUP), and the total lipid fraction (TL) extracted and purified from Chlorella sorokiniana (CS) on the proliferation and cytokine profile of sheep peripheral blood mononuclear cells (PBMCs). Cells were cultured with 0.4 mg/mL and 0.8 mg/mL concentrations of each extract (UP, AUP, and TL fractions) and activated with 5 μg/mL concanavalin A (ConA) and 1 μg/mL lipopolysaccharide (LPS) at 37 °C for 24 h. PBMCs cultured with ConA and LPS represented the stimulated cells (SC), and PBMCs without ConA and LPS represented the unstimulated cells (USC). Cell-free supernatants were collected to determine IL-10, IL-1β, and IL-6 secretions; on cells, measurement of proliferation was performed. All the extracts tested significantly decreased the cell proliferation; in particular, the UP fraction at 0.4 mg/mL showed the lowest proliferative response. Furthermore, at 0.8 mg/mL, the UP fraction enhanced IL-10 secretion. On the contrary, the TL fraction at 0.4 mg/mL induced an increase in IL-10, IL-6, and, to a lesser extent, IL-1β secretions by cells. The AUP fraction did not change cytokine secretion. The results demonstrated that CS extracts could be useful ingredients in animal feed in order to minimize the use of antibiotics by modulating cell proliferation and cytokine response.
The Efficiency of Xylanase in Broiler Chickens Fed with Increasing Dietary Levels of Rye
Authors: Arczewska-Wlosek Anna , Swiatkiewicz Sylwester , Bederska-Lojewska Dorota , Orczewska-Dudek Sylwia , Szczurek Witold , Boros Danuta , Fras Anna , Tomaszewska Ewa , Dobrowolski Piotr , Muszynski Siemowit , Kwiecien Małgorzata , Schwarz Tomasz
Published: February 2019

In this paper, we present a study on the evaluation of the effect of xylanase addition to a diet with an increasing content of modern hybrid rye (Brasetto variety) on the performance indices and viscosity of small intestine content in broiler chickens. A total of 560 1-day-old male Ross 308 chickens were randomly assigned to 1 of 10 treatments, each comprising 7 replicate cages, with 8 male birds per cage. A 5 × 2 factorial arrangement was employed, with five dietary levels of ground rye (0%, 5%, 10%, 15%, and 20%). All the diets were either unsupplemented or supplemented with xylanase (200 mg/kg of feed; with minimum xylanase activity 1000 FXU/g). In the starter rearing period (1–21 days of age), the inclusion of rye (without xylanase supplementation) to the diet, even at the lowest dietary level (5%), negatively affected body weight gain (p < 0.05); there was no effect on feed intake and feed conversion ratio. In older chickens (the grower-finisher rearing period; 22–42 days of age), none of the dietary levels of rye (5–20%) affected growth performance indices. Similarly, no significant effect of increasing dietary level of rye was found for the entire rearing period (1–42 days of age). Diet supplementation with xylanase improved body weight gain and feed conversion ratio in chickens from 1 to 21 days of age. No positive effect of enzyme was found in older birds. No significant effects of the experimental factors used were noticed on the results of slaughter analysis, i.e., the carcass yield, breast meat yield, abdominal fat, and relative weight of the liver and gizzard. A high dietary concentration of rye (20%) increased the viscosity of small intestine content (p < 0.05); however, diet supplementation with xylanase significantly alleviated this effect. The findings of this experiment indicated that modern hybrid rye grain may be used at a 20% dietary level in broiler diets during the second feeding phase, i.e., from 22 to 42 days of age, without any detrimental influence on growth performance indices, while enzyme (xylanase) positively affected body weight gain and feed conversion ratio in younger chicks (1–21 days of age).
Influence of Fuel Injection, Turbocharging and EGR Systems Control on Combustion Parameters in an Automotive Diesel Engine
Authors: Zamboni Giorgio
Published: February 2019

Indicated pressure diagrams were measured during experimental campaigns on the control of fuel injection, turbocharging and hybrid exhaust gas recirculation systems in an automotive downsized diesel engine. Three-part load operating conditions were selected for four test sets, where strategies aimed at the reduction of NOX emissions and fuel consumption, limiting penalties in soot emissions and combustion noise were applied to the selected systems. Processing of in-cylinder pressure signal, its first derivative and curves of the rate of heat release allowed us to evaluate seven parameters related to the combustion centre and duration, maximum values of pressure, heat release and its first derivative, heat released in the premixed phase and a combustion noise indicator. Relationships between these quantities and engine operating, energy and environmental parameters were then obtained by referring to the four test sets. In the paper, the most significant links are presented and discussed, aiming at a better understanding of the influence of control variables on the combustion process and the effects on engine behaviour. The proposed methodology proved to be a consistent tool for this analysis, useful for supporting the application of alternative fuels or advanced combustion modes.
Fabrication of Multiscale-Structure Wafer-Level Microlens Array Mold
Authors: Xie Shuping , Wan Xinjun , Wei Xiaoxiao
Published: February 2019

The design and manufacture of cost-effective miniaturized optics at wafer level, usingadvanced semiconductor-like techniques, enables the production of reduced form-factor cameramodules for optical devices. However, suppressing the Fresnel reflection of wafer-level microlensesis a major challenge. Moth-eye nanostructures not only satisfy the antireflection requirementof microlens arrays, but also overcome the problem of coating fracture. This novel fabricationprocess, based on a precision wafer-level microlens array mold, is designed to meet the demandfor small form factors, high resolution, and cost effectiveness. In this study, three different kinds ofaluminum material, namely 6061-T6 aluminum alloy, high-purity polycrystalline aluminum, and purenanocrystalline aluminum were used to fabricate microlens array molds with uniform nanostructures.Of these three materials, the pure nanocrystalline aluminum microlens array mold exhibited auniform nanostructure and met the optical requirements. This study lays a solid foundation for theindustrial acceptation of novel and functional multiscale-structure wafer-level microlens arrays andprovides a practical method for the low-cost manufacture of large, high-quality wafer-level molds.
The Correlation between Users’ Cognitive Characteristics and Visualization Literacy
Authors: Lee Sukwon , Kwon Bum Chul , Yang Jiming , Lee Byung Cheol , Kim Sung-Hee
Published: February 2019

One of the ultimate goals of studies on visualization literacy is to improve users’ visualization literacy through education and training. Even though users’ cognitive characteristics may significantly affect learning and responding processes in general, studies have addressed the relationships between users’ cognitive characteristics and visualization literacy. As a first step toward discovering the relationships, we conducted an empirical study to investigate the correlation between cognitive characteristics and visualization literacy. Our first study focuses on testing the correlation between visualization and three cognitive characteristics: numeracy, need for cognition, and visualizer-verbalizer style. In this study, we measured 178 participants’ visualization literacy and the level of the three cognitive characteristics using the Visualization Literacy Assessment Test (VLAT), the Decision Research Numeracy Test (DRNT), the Need for Cognition Scale (NCS), and the Verbalizer-Visualizer Questionnaire (VVQ) through a crowdsourcing experiment. Our test results confirmed that a correlation exists between visualization literacy and both numeracy and need for cognition. Based on our test results, we discuss the implications for education to enhance visualization literacy and future studies to investigate on related user characteristics.
Heavy Metal Ion Detection Platforms Based on a Glutathione Probe: A Mini Review
Authors: Zhang Jian , Sun Xuan , Wu Jayne
Published: February 2019

Globally, heavy metal ion (HMI) contamination is on the rise, posing an ever-increasing risk to ecological and human health. In recent years, great research effort has been devoted to the sensitive detection and quantitative analysis of HMIs. Low cost, sensitive, selective, and rapid methods for HMI detection are of growing demand, and HMI biosensors have great potential in meeting this need due to their timeliness, cost-effectiveness and convenience in operation. Glutathione is known for its strong ability to bind with toxic heavy metal ions, in addition to its water solubility, stable activity and ready availability. As a result, glutathione is becoming a molecular probe of choice in the preparation of sensors for sensitive, affordable, and accessible HMI detection. This review summarizes the results from various glutathione-based HMI detection strategies reported in recent years, which are categorized according to their signal transduction methods. Their operation and implementation, along with figures of merit such as limit of detection, selectivity, and response time, are discussed and compared. Based on the review, both individual HMI detection and simultaneous detection of multiple HMIs can be realized under specific reaction conditions, showing the great potential of glutathione-based detection to realize various types of practical HMI detection.
A Theoretical Model for the Triple Phase Boundary of Solid Oxide Fuel Cell Electrospun Electrodes
Authors: Kong Wei , Zhang Mengtong , Han Zhen , Zhang Qiang
Published: February 2019

Electrospinning is a new state-of-the-art technology for the preparation of electrodes for solid oxide fuel cells (SOFC). Electrodes fabricated by this method have been proven to have an experimentally superior performance compared with traditional electrodes. However, the lack of a theoretic model for electrospun electrodes limits the understanding of their benefits and the optimization of their design. Based on the microstructure of electrospun electrodes and the percolation threshold, a theoretical model of electrospun electrodes is proposed in this study. Electrospun electrodes are compared to fibers with surfaces that were coated with impregnated particles. This model captures the key geometric parameters and their interrelationship, which are required to derive explicit expressions of the key electrode parameters. Furthermore, the length of the triple phase boundary (TPB) of the electrospun electrode is calculated based on this model. Finally, the effects of particle radius, fiber radius, and impregnation loading are studied. The theory model of the electrospun electrode TPB proposed in this study contributes to the optimization design of SOFC electrospun electrode.
Cryptanalysis of Permutation–Diffusion-Based Lightweight Chaotic Image Encryption Scheme Using CPA
Authors: Li Ming , Zhou Kanglei , Ren Hua , Fan Haiju
Published: February 2019

In order to meet the requirement of secure image communication in a resource-constrained network environment, a novel lightweight chaotic image encryption scheme based on permutation and diffusion has been proposed. It was claimed that this scheme can resist differential attacks, statistical attacks, etc. However, the original encryption scheme is found to be vulnerable and insecure to chosen-plaintext attack (CPA). In this paper, the original encryption scheme is analyzed comprehensively and attacked successfully. Only by choosing a full zero image as the chosen-plaintext of the diffusion phase, the encrypted image can be restored into permutation-only phase, and by applying the other chosen images as the chosen-plaintexts of the permutation phase, the map matrix which is equivalent to the secret key of the permutation phase can be further revealed. Experiments and analysis verify the feasibility of our proposed attack strategy.
Fabrication of Self-Healable Magnetic Nanocomposites via Diels−Alder Click Chemistry
Authors: Lee Yi-Huan , Zhuang Yan-Nian , Wang Hsin-Ta , Wei Ming-Feng , Ko Wen-Chi , Chang Wei-Jen , Way Tun-Fun , Rwei Syang-Peng
Published: February 2019

In this study, we report a novel approach to fabricate an organic/inorganic magnetic hybrid system capable of self-healing, wherein a polycaprolactone-poly(furfuryl glycidyl ether) copolymer (PCLF) serving as the structure template was first synthesized, followed by the incorporation of iron oxide nanoparticles-decorated multiwalled carbon nanotubes (IONPs-MWCNTs) and 1,1′-(methylenedi-4,1-phenylene)bismaleimide (BMI) into the polymer matrix to form a covalently crosslinked hybrid network via a Diels−Alder (DA) reaction. For this system, the reactive combination of diene and dienophile from furan/maleimide, MWCNT/furan, and MWCNT/maleimide could facilely induce multiple DA reactions that imparted a versatile route to efficiently introduce IONPs-MWCNTs into the organic polymer hosts, resulting in a uniform distribution of IONPs-MWCNTs that led to a hybrid system with superparamagnetic properties. Beside the magnetic behavior, such material synergistically exhibited a superior ability for healing scratch defects via a retro-DA reaction. Therefore, this crosslinked PCLF/BMI/IONPs-MWCNTs hybrid system which exhibits multifunctional properties including superparamagnetic behavior and self-repairability can serve as an intelligent material for developing advanced electromagnetic applications.
Charge-Exchange Emission from Hydrogen-Like Carbon Ions Colliding with Water Molecules
Authors: Bodewits Dennis , Hoekstra Ronnie
Published: February 2019

Absolute Extreme Ultraviolet emission cross-sections have been measured for collisions between C 5 + and H 2O in the range of 0.113 to 3.75 keV/amu (170–979 km/s). These results are used to derive velocity-dependent triplet-to-singlet ratios and emission cross-sections of the Cv K-series following single-electron capture. Comparison with existing measurements of integral charge-changing cross-sections indicates that auto-ionizing multi-electron capture is a significant reactions channel. This reaction may indirectly populate the n = 2 states and thus add strength to the K α emission of Cv ions thereby co-determining the hardness ratio of K-series emission of Cv.
Hydrothermal Carbonization of Brewery’s Spent Grains for the Production of Solid Biofuels
Authors: Jackowski Mateusz , Semba Damian , Trusek Anna , Wnukowski Mateusz , Niedzwiecki Lukasz , Baranowski Marcin , Krochmalny Krystian , Pawlak-Kruczek Halina
Published: February 2019

To make a beer there are four essential ingredients needed: water, malt, hops, and yeast. After brewing process, the main wastes are spent grains. These are often used as additions to fodders in animal husbandry. This study presents preliminary results of an investigation aiming to determine the feasibility of an alternative use of spent grains as a potential source of solid fuel. This source of energy could make breweries partly sustainable in terms of their energy supply. Such an approach may be feasible especially in large scale industrial breweries. This preliminary study presents encouraging results, showing improvements in terms of the fuel properties of the spent grain after its valorization through hydrothermal carbonization. Moreover, qualitative GC-MS analysis also indicates potential feasibility of the liquid byproduct of the hydrothermal carbonization of spent grain for biogas production. Results of proximate, ultimate, and DTG analyses show that hydrothermal carbonization of spent grain could improve its fuel properties and make it an especially suitable feedstock for fast pyrolysis and gasification. Improvement of HHV is also an improvement in terms of combustion.
Listeria monocytogenes in Milk: Occurrence and Recent Advances in Methods for Inactivation
Authors: Lee Sarah Hwa In , Cappato Leandro Pereira , Guimarães Jonas Toledo , Balthazar Celso Fasura , Rocha Ramon Silva , Franco Larissa Tuanny , da Cruz Adriano Gomes , Corassin Carlos Humberto , de Oliveira Carlos Augusto Fernandes
Published: February 2019

Milk is one of the most important food items consumed by humans worldwide. In addition to its nutritional importance, milk is an excellent culture medium for microorganisms, which may include pathogens such as Listeria monocytogenes (L. monocytogenes). Traditional processing of milk for direct consumption is based on thermal treatments that efficiently eliminate pathogens, including pasteurization or sterilization. However, the occurrence of L. monocytogenes in milk as a consequence of failures in the pasteurization process or postpasteurization contamination is still a matter of concern. In recent years, consumer demand for minimally processed milk has increased due to the perception of better sensory and nutritional qualities of the products. This review deals with the occurrence of L. monocytogenes in milk in the last 10 years, including regulatory aspects, and recent advances in technologies for the inactivation of this pathogen in milk. The results from studies on nonthermal technologies, such as high hydrostatic pressure, pulsed electric fields, ultrasounds, and ultraviolet irradiation, are discussed, considering their potential application in milk processing plants.
Quality Acceptability, Nutritional Composition and Antioxidant Properties of Carrot-Cucumber Juice
Authors: Aderinola Taiwo Ayodele , Abaire Kemi Elizabeth
Published: February 2019

Fresh vegetables (carrot and cucumber) were juiced using a juice extractor. The extracted juice was then divided into five varying proportions: A (100% carrot juice), B (80% carrot, 20% cucumber), C (70% carrot, 30% cucumber), D (50% carrot, 50% cucumber) and E (100% cucumber). The juice blends were then analyzed for proximate, mineral and vitamin compositions. The phytochemical and the antioxidant properties were also determined. The proximate composition result revealed very high moisture (82.03–83.85%), relatively low carbohydrate (5.23–10.57%) and very low crude protein (1.75–4.14%) contents. For the micronutrients, potassium (14.70–32.10 mg/100 mL) and vitamin C (14.48–24.48 mg/100 mL) were more predominant when compared to the other micronutrients that were determined. The pH was mildly acidic (5.90–6.21) and the Brix value ranged between 3.51 and 7%. The antioxidant result indicated that better bioactivity could be obtained from the blends than the individual juices. While there were no statistically significant differences in the sensory properties of the juices, the 100% carrot juice was rated higher in all the attributes evaluated. Therefore, it was concluded that a blend of carrot and cucumber at a 50:50 ratio offered comparable nutritional and better antioxidative quality when compared to other blends.
Extracellular Vesicles from the Protozoa Acanthamoeba castellanii: Their Role in Pathogenesis, Environmental Adaptation and Potential Applications
Authors: Gonçalves Diego de Souza , Ferreira Marina da Silva , Guimarães Allan J.
Published: February 2019

Extracellular vesicles (EVs) are membranous compartments of distinct cellular origin and biogenesis, displaying different sizes and include exosomes, microvesicles, and apoptotic bodies. The EVs have been described in almost every living organism, from simple unicellular to higher evolutionary scale multicellular organisms, such as mammals. Several functions have been attributed to these structures, including roles in energy acquisition, cell-to-cell communication, gene expression modulation and pathogenesis. In this review, we described several aspects of the recently characterized EVs of the protozoa Acanthamoeba castellanii, a free-living amoeba (FLA) of emerging epidemiological importance, and compare their features to other parasites’ EVs. These A. castellanii EVs are comprised of small microvesicles and exosomes and carry a wide range of molecules involved in many biological processes like cell signaling, carbohydrate metabolism and proteolytic activity, such as kinases, glucanases, and proteases, respectively. Several biomedical applications of these EVs have been proposed lately, including their use in vaccination, biofuel production, and the pharmaceutical industry, such as platforms for drug delivery.
Novel Tubular Carbon Membranes Prepared from Natural Rattans
Authors: He Xuezhong
Published: February 2019

The novel tubular carbon membranes produced from natural materials are, for the first time, reported. The novelty of this idea is to use natural rattans as precursors for making carbon membranes to address the challenges of cellulose polymers. The rattan precursors were carbonized to present evenly distributed channels inside the tubular carbon membranes. Each channel has an inner diameter of 2 × 10−4 m with a dense-selective inner layer and a porous outer layer. Future work on selection of suitable rattans, proper pre-treatment, carbon structure tailoring can be conducted to open a new research field of carbon membranes/materials.
Targeting Glioblastoma Stem Cells with 2-Deoxy-D-Glucose (2-DG) Potentiates Radiation-Induced Unfolded Protein Response (UPR)
Authors: Shah Sumedh S. , Rodriguez Gregor A. , Musick Alexis , Walters Winston M. , de Cordoba Nicolas , Barbarite Eric , Marlow Megan M. , Marples Brian , Prince Jeffrey S. , Komotar Ricardo J. , Vanni Steven , Graham Regina M.
Published: February 2019

Glioblastoma (GBM) is the most common and aggressive primary brain tumor in adults, and despite optimized treatment options, median survival remains dismal. Contemporary evidence suggests disease recurrence results from expansion of a robustly radioresistant subset of GBM progenitor cells, termed GBM stem cells (GSCs). In this study, we utilized transmission electron microscopy to uncover ultrastructural effects on patient-derived GSC lines exposed to supratherapeutic radiotherapy levels. Elevated autophagosome formation and increased endoplasmic reticulum (ER) internal diameter, a surrogate for ER stress and activation of unfolded protein response (UPR), was uncovered. These observations were confirmed via protein expression through Western blot. Upon interrogating genomic data from an open-access GBM patient database, overexpression of UPR-related chaperone protein genes was inversely correlated with patient survival. This indicated controlled UPR may play a role in promoting radioresistance. To determine if potentiating UPR further can induce apoptosis, we exposed GSCs to radiation with an ER stress-inducing drug, 2-deoxy-D-glucose (2-DG), and found dose-dependent decreases in viability and increased apoptotic marker expression. Taken together, our results indicate GSC radioresistance is, in part, achieved by overexpression and overactivation of ER stress-related pathways, and this effect can be overcome via potentiation of UPR, leading to loss of GSC viability.
Development of TiO2-Carbon Composite Acid Catalyst for Dehydration of Fructose to 5-Hydroxymethylfurfural
Authors: Songo Morongwa Martha , Moutloali Richard , Ray Suprakas Sinha
Published: February 2019

A TiO2-Carbon (TiO2C) composite was prepared using the microwave-assisted method and sulfonated using fuming sulfuric acid to produce a TiO2C solid acid catalyst. The prepared solid acid catalyst was characterised using scanning electron microscopy, Brunauer-Emmett-Teller analysis, Fourier transform infrared spectroscopy, and X-ray diffraction. Crystallinity analysis confirmed that TiO2C has an anatase structure, while analysis of its morphology showed a combination of spheres and particles with a diameter of 50 nm. The TiO2C solid acid catalyst was tested for use in the catalytic dehydration of fructose to 5-hydroxymethylfurfural (5-HMF). The effect of reaction time, reaction temperature, catalyst dosage, and solvent were investigated against the 5-HMF yield. The 5-HMF yield was found to be 90% under optimum conditions. The solid acid catalyst is very stable and can be reused for four catalytic cycles. Hence, the material has great potential for use in industrial applications and can be used for the direct conversion of fructose to 5-HMF because of its high activity and high reusability.
Incorporating Hierarchy into Conventional Zeolites for Catalytic Biomass Conversions: A Review
Authors: Khan Wasim , Jia Xicheng , Wu Zhijie , Choi Jungkyu , Yip Alex
Published: February 2019

Zeolites are promising catalysts that are widely used in petrochemical, oil, and gas industries due to their unique characteristics, such as ordered microporous networks, good hydrothermal stability, large surface area, tunable acidity, and shape-selectivity. Nevertheless, the sole presence of microporous channels in zeolites inevitably restricts the diffusion of bulky reactants and products into and out of the microporous networks, leading to retarded reaction rates or catalyst deactivation. This problem can be overcome by developing hierarchical zeolites which involve mesoporous and macroporous networks. The meso- and macro-porosities can enhance the mass transport of molecules and simultaneously maintain the intrinsic shape selectivity of zeolite microporosity. Hierarchical zeolites are mainly developed through post-synthesis and pre-synthesis or in situ modification of zeolites. In this review, we evaluated both pre-synthesis and post-synthesis modification strategies with more focus on post-synthesis modification strategies. The role of various synthesis strategies on the intrinsic properties of hierarchical zeolites is discussed. The catalytic performance of hierarchical zeolites in important biomass reactions, such as catalytic pyrolysis of biomass feedstock and upgradation of bio-oil, has been summarized. The utilization of hierarchical zeolites tends to give a higher aromatic yield than conventional zeolites with microporosity solely.
Enantioselective Catalytic Transformations of Barbituric Acid Derivatives
Authors: Segovia Claire , Lebrêne Arthur , Levacher Vincent , Oudeyer Sylvain , Brière Jean-François
Published: February 2019

Since the beginning of the 20th century, numerous research efforts made elegant use of barbituric acid derivatives as building blocks for the elaboration of more complex and useful molecules in the field of pharmaceutical chemistry and material sciences. However, the construction of chiral scaffolds by the catalytic enantioselective transformation of barbituric acid and derivatives has only emerged recently. The specific properties of these rather planar scaffolds, which also encompass either a high Brønsted acidity concerning the native barbituric acid or the marked electrophilic character of alkylidene barbituric acids, required specific developments to achieve efficient asymmetric processes. This review covers the enantioselective catalytic reactions developed for barbituric acid platforms using an organocatalytic and metal-based enantioselective sequences. These achievements currently allow several unique addition and annulation reactions towards the construction of high valued chiral heterocycles from barbituric acid derivatives along with innovative enantioselective developments.
New and Advanced Porous Carbon Materials in Fine Chemical Synthesis. Emerging Precursors of Porous Carbons
Authors: Pérez-Mayoral Elena , Matos Inês , Bernardo Maria , Fonseca Isabel
Published: February 2019

The efficiency of porous carbons in fine chemical synthesis, among other application fields, has been demonstrated since both the porous structure and chemical surface provide the appropriated chemical environment favoring a great variety of relevant chemical transformations. In recent years, metal organic frameworks (MOFs) and covalent organic frameworks (COFs) have emerged as interesting opportunities in the preparation of porous carbons with improved physico-chemical properties. Direct calcination of MOFs or COFs, in the presence or not of others carbon or heteroatom sources, could be considered an easy and practical approach for the synthesis of highly dispersed heteroatom-doped porous carbons but also new porous carbons in which single atoms of metallic species are present, showing a great development of the porosity; both characteristics of supreme importance for catalytic applications. The goal of this review is to provide an overview of the traditional methodologies for the synthesis of new porous carbon structures together with emerging ones that use MOFs or COFs as carbon precursors. As mentioned below, the catalytic application in fine chemical synthesis of these kinds of materials is at present barely explored, but probably will expand in the near future.
Revisiting Telomere Shortening in Cancer
Authors: Okamoto Keiji , Seimiya Hiroyuki
Published: February 2019

Telomeres, the protective structures of chromosome ends are gradually shortened by each cell division, eventually leading to senescence or apoptosis. Cancer cells maintain the telomere length for unlimited growth by telomerase reactivation or a recombination-based mechanism. Recent genome-wide analyses have unveiled genetic and epigenetic alterations of the telomere maintenance machinery in cancer. While telomerase inhibition reveals that longer telomeres are more advantageous for cell survival, cancer cells often have paradoxically shorter telomeres compared with those found in the normal tissues. In this review, we summarize the latest knowledge about telomere length alterations in cancer and revisit its rationality. Finally, we discuss the potential utility of telomere length as a prognostic biomarker.
Pancreatic Stellate Cells Serve as a Brake Mechanism on Pancreatic Acinar Cell Calcium Signaling Modulated by Methionine Sulfoxide Reductase Expression
Authors: Liu Jin Shuai , Cui Zong Jie
Published: February 2019

Although methionine sulfoxide reductase (Msr) is known to modulate the activity of multiple functional proteins, the roles of Msr in pancreatic stellate cell physiology have not been reported. In the present work we investigated expression and function of Msr in freshly isolated and cultured rat pancreatic stellate cells. Msr expression was determined by RT-PCR, Western blot and immunocytochemistry. Msr over-expression was achieved by transfection with adenovirus vectors. Pancreatic stellate cells were co-cultured with pancreatic acinar cells AR4-2J in monolayer culture. Pancreatic stellate and acinar cell function was monitored by Fura-2 calcium imaging. Rat pancreatic stellate cells were found to express MsrA, B1, B2, their expressions diminished in culture. Over-expressions of MsrA, B1 or B2 were found to enhance ATP-stimulated calcium increase but decreased reactive oxygen species generation and lipopolysaccharide-elicited IL-1 production. Pancreatic stellate cell-co-culture with AR4-2J blunted cholecystokinin- and acetylcholine-stimulated calcium increases in AR4-2J, depending on acinar/stellate cell ratio, this inhibition was reversed by MsrA, B1 over-expression in stellate cells or by Met supplementation in the co-culture medium. These data suggest that Msr play important roles in pancreatic stellate cell function and the stellate cells may serve as a brake mechanism on pancreatic acinar cell calcium signaling modulated by stellate cell Msr expression.
CRISPR/Cas9-Mediated Hitchhike Expression of Functional shRNAs at the Porcine miR-17-92 Cluster
Authors: Lu Chao , Pang Daxin , Li Mengjing , Yuan Hongming , Yu Tingting , Huang Peixuan , Li Jianing , Chen Xue , Jiao Huping , Xie Zicong , Ouyang Hongsheng
Published: February 2019

Successful RNAi applications depend on strategies allowing stable and persistent expression of minimal gene silencing triggers without perturbing endogenous gene expression. In this study, we proposed an endogenous microRNA (miRNA) cluster as a novel integration site for small hairpin RNAs (shRNAs). We successfully integrated exogenous shRNAs at the porcine miRNA-17-92 (pmiR-17-92) cluster via a CRISPR/Cas9-mediated knock-in strategy. The anti-EGFP or anti-CSFV shRNAs could be stably and effectively expressed at the control of the endogenous promoter of the pmiR-17-92 cluster. Importantly, we confirmed that hitchhike expression of anti- classical swine fever (CSFV) shRNA had no effect on cell growth, blastocyst development and endogenous pmiR-17-92 expression in selected transgene (TG) porcine fetal fibroblasts (PFFs) clones. Moreover, these TG PFFs could inhibit the replication of CSFV by half and could be further used for generation of transgenic pigs. Taken together, these results show that our RNA interference (RNAi) expression strategy benefits numerous applications, from miRNA, genome and transgenic research, to gene therapy.