bluuebunny/crossref_metadata_2025 huggingface dataset:
Estado actual de la enseñanza del Análisis Musical en instituciones de
educación superior, y el uso de un lenguaje académico asociado, en Chile.
Authors:   , Púa Reyes Claudio Hernan
Published: November 2024

La presente tesis tiene por objetivo el evaluar el estado actual del
lenguaje académico en el Análisis Musical, impartido en instituciones de
educación superior en Chile. El análisis musical en la actualidad representa un
campo de estudio muy amplio, activo y estrechamente vinculado con la teoría
musical. Éste se establece como una disciplina que promueve la generación de un
espacio epistemológico de pensamiento y crítica, reforzado con múltiples
investigaciones, libros y artículos, en las que se desarrollan diversas
corrientes de análisis, y en el que la bajada de información involucra aspectos
pedagógicos, especialmente el uso de lenguaje académico para la transmisión y
divulgación de conocimientos. Esta descripción alude principalmente al mundo
académico anglófono; por el contrario, en la realidad chilena, inserta en el
contexto hispanohablante, el análisis musical está implementado curricularmente
en distintas carreras, pero con evidentes diferencias en cuanto al uso de
bibliografías, recursos pedagógicos y metodologías para el trabajo de aula. Para
el cumplimiento del objetivo general, he considerado necesario exponer una
revisión disciplinar del análisis musical, sus características históricas y
principales corrientes de pensamiento, para luego relacionarlas con el uso del
lenguaje académico y las características que éste adquiere en el trabajo
pedagógico a nivel de aula universitaria. A continuación, se expone una
caracterización de las carreras musicales en la educación superior en Chile,
principalmente los tipos de carreras y menciones impartidas, El diálogo entre
los datos obtenidos y los fundamentos del análisis musical como disciplina
teórica permitió singularizar las mallas curriculares y la cobertura del
análisis musical en cada carrera. Esta base posibilitó el desarrollo de una
metodología de investigación, que constó de 2 partes: la revisión de una muestra
de programas académicos de cursos de análisis musical, considerando objetivos y
metodologías, y el desarrollo de una encuesta aplicada a una muestra de
académicos que imparten este curso, en el que se les expone a problemas de
análisis de partituras donde se constate el dominio de lenguaje académico, y se
les plantean una serie de preguntas con el fin de indagar en torno a sus mejores
prácticas pedagógicas. Los resultados de la investigación informan que los
programas de Análisis Musical aluden a conocimientos ontológicos que invaden el
espacio epistemológico esperable para este curso. La encuesta académica refrenda
lo observado en los programas, al constatarse la práctica de un estilo de
lenguaje mayormente descriptivo, versus un uso minoritario del lenguaje que
derive hacia lo explicativo, deseable para la práctica del análisis. Esto lleva
a concluir que el uso del lenguaje académico en el Análisis Musical en Chile
tiene un bajo nivel de actualización, tendiente al estancamiento.
Propuesta de criterios determinantes para una fluida navegación de usuarios
por el sistema de salud en Chile
Authors:   , Riveros Torres Sara
Published: November 2024

La alfabetización en salud de navegación afecta la vida de las personas, por
ejemplo, en el acceso a los servicios de prevención o el costo de las
atenciones, asociándose a resultados cómo el riesgo de hospitalización, entre
otros. El presente estudio pretende identificar desde la perspectiva de los
usuarios, un conjunto de criterios para su fluida navegación por el sistema y
servicios de salud al momento de implementar políticas de salud en Chile.
Métodos: Se realizó un estudio cualitativo descriptivo con análisis temático
bajo el enfoque de Braun y Clarke. Se seleccionaron 10 pacientes del seguro
público FONASA mediante un muestreo no aleatorio por propósito. Los datos se
recolectaron mediante entrevistas semiestructuradas. Resultados: Del análisis de
datos se establecieron 4 dimensiones de las cuales se desglosaron 16 criterios
que se deben cumplir para mejorar la navegación de los usuarios por el sistema
de salud chileno, ya que se identificaron una baja comprensión de su
funcionamiento y sus mecanismos de acceso, un bajo conocimiento de sus derechos
como usuario, decisiones de salud mediada por la red de apoyo, la experiencia
previa que tenga en el sistema y/o la relación con el personal de salud y el
trato. Conclusiones: Para abordar las brechas identificadas es necesario que los
tomadores de decisiones apliquen criterios enfocados en mejorar la fluidez de
los usuarios por el sistema.
Views of ESP Learners on Code-Switching in Business English Classrooms
Authors: Su Chengchieh
Published: November 2024

This study investigates the perceptions of Business English students at Zhaoqing University in China regarding code-switching in English for Specific Purposes (ESP) classrooms. The study employed a survey and thematic analysis, targeting 33 Business English majors to explore their views on the prevalence, functions, and impacts of code-switching on comprehension, teacher-student relationships, and classroom atmosphere. Results indicate that students generally perceive code-switching as beneficial for improving comprehension, fostering teacher-student relationships, and enhancing the classroom atmosphere. Key functions of code-switching identified include translation, topic switching, and checking comprehension. While students appreciate the role of code-switching in clarifying complex concepts, there is a concern that excessive use of the native language may impede language development. The study recommends the judicious use of code-switching to balance support for comprehension with practice in the target language. Future research should address the study’s limitations, including its small sample size and lack of teacher behavior analysis, for a deeper understanding of code-switching in ESP settings.
Impact of Plant Bioregulators on Growth, Yield, Quality and Economic Feasibility of Guava (Psidium guajava L.) in Central Region of Punjab, India
Authors: Sharma Sonia , Sharma Rohit , Chandra Nikesh , Singh Amritpal , Tanvi  , Singh Jaskirat , Singh Arsdeep
Published: November 2024

Guava holds significant importance in India due to its high nutritional value, affordability, and ability to grow in diverse climatic conditions. It plays a vital role in the economy and is a major source of vitamins, especially vitamin C, for millions. A study conducted from 2022 to 2024 at the Department of Agriculture, Agriculture Research Farm, Mata Gujri College, Fatehgarh Sahib, Punjab, evaluated the effects of various plant growth regulators on guava. The experiment involved ten treatments; each replicated three times using a randomized block design. The treatments included: PBR1 (NAA 50 ppm), PBR2 (NAA 75 ppm), PBR3 (NAA 100 ppm), PBR4 (GA3 50 ppm), PBR5 (GA3 100 ppm), PBR6 (GA3 150 ppm), PBR7 (Triacontanol 25 ppm), PBR8 (Triacontanol 50 ppm), PBR9 (Triacontanol 75 ppm), and PBR10 (Control). Among the treatments, PBR3 (NAA 100 ppm) produced the best results in terms of fruit volume (85.72 cm3), minimum firmness (8.05), specific gravity (1.02%), ascorbic acid content (252.85mg/100g), total sugar content (10.73%) and TSS (10.86 0Brix) and minimum found in PBR10 (control). The highest net return of Rs. 454,237 and the best benefit-cost (B:C) ratio were also recorded for PBR3 (NAA 100 ppm). Based on these findings, the use of plant growth regulators, particularly NAA 100 ppm, is recommended to enhance both the yield and quality of guava fruits.
Avaliação dos Aspectos Relacionados à Memória e a Dor Músculo Esqueléticas em Sequelas Neurológicas Pós-Covid
Authors: C.  Silva Aline , R. A. Oliveira Mariana , S. G. Oliveira Camilly , M. R. Battisti Victor , M. Freitas Priscila
Published: November 2024

The Covid-19 pandemic, caused by SARS-CoV-2, deeply impacts global health, aff ecting both the physical and mental well-being of those infected. Besides respiratory symptoms, the infection can lead to persistent neurological and musculoskeletal manifestations. The invasion of the central nervous system by the virus, through various means, triggers infl ammations that impair cognition and memory. Patients report sequelae such as “brain fog,” memory impairment, and fatigue, even after the acute phase. Myalgia, fatigue, and back pain are common in terms of musculoskeletal aspects, suggesting a direct invasion of the virus into muscles, along with infl ammatory cytokines and treatment eff ects. Post-Covid-19 syndrome persists for more than 12 weeks, while long Covid-19 syndrome is characterized by fatigue, memory problems, and shortness of breath for over 6 weeks. Several factors cause such neurological and musculoskeletal problems, so it is extremely important for health professionals to research the range of factors that can contribute to pain and post-Covid-19 cognitive changes, knowing their infl uences on the individual’s life and the people with whom they relate. Given that chronic pain causes suff ering in several areas of life, in this work, we will carry out a narrative review on important aspects related to memory and musculoskeletal pain related to post-Covid neurological sequelae.Keywords: Long Covid, central nervous system, musculoskeletal pain, memory, SARS-CoV-2
Structural insights into interactions between viral suppressor of RNA silencing protein p19 mutants and small RNAs
Authors: Foss Dana V. , Schirle Nicole T. , MacRae Ian J. , Pezacki John Paul
Published: April 2019

Viral suppressors of RNA silencing (VSRSs) are a diverse group of viral proteins that have evolved to disrupt eukaryotic RNA silencing pathways, thereby contributing to viral pathogenicity. The p19 protein is a VSRS that selectively binds to short interfering RNAs (siRNAs) over microRNAs (miRNAs). Mutational analysis has identified single amino acid substitutions that reverse this selectivity through new high‐affinity interactions with human miR‐122. Herein, we report crystal structures of complexed p19‐T111S (2.6 Å), p19‐T111H (2.3 Å) and wild‐type p19 protein (2.2 Å) from the Carnation Italian ringspot virus with small interfering RNA (siRNA) ligands. Structural comparisons reveal that these mutations do not lead to major changes in p19 architecture, but instead promote subtle rearrangement of residues and solvent molecules along the p19 midline. These observations suggest p19 uses many small interactions to distinguish siRNAs from miRNAs and perturbing these interactions can create p19 variants with novel RNA‐recognition properties.

Database

Model data are deposited in the PDB database under the accession numbers 6BJG, 6BJH and 6BJV.
Method for the determination of carbon monoxide in workplace air using a Fourier‐transform infrared spectrometer (FTIR spectrometer) [Air Monitoring Methods, 2019]
Authors: Gluschko A. , Befurt R. , Brock T.H. , Hebisch R. , Hartwig A. ,   MAK Commission
Published: April 2019

This analytical method is a validated measurement procedure for the determination of carbon monoxide in workplace air. The sampling is performed stationary. In the measurement procedure the concentration of carbon monoxide is measured continuously and recorded directly. The sample flow rate is set to max 2.0 L/min. The detector records an interferogram, from which the absorption spectrum is obtained by means of an internal Fourier transform calculation. The signal patterns in the IR spectrum are compared, and the concentrations of carbon monoxide in workplace air are determined. This method is suitable for measurement at the workplace over longer time periods as well as for short‐term measurement. It is also possible to read the current CO concentration at any time. The limit of quantification is 0.29 ppm and the limit of detection is 0.09 ppm for a measurement period of one minute. For a measurement period of 20 seconds a limit of quantification of 0.41 ppm and a limit of detection of 0.12 ppm were obtained.

Joint Publication of the Analytical Subcommittee of the Chemistry Board of Experts of the Expert Committee Raw Materials and Chemical Industry of the German Social Accident Insurance and the working group “Air Analyses” of the Permanent Senate Commission of the Deutsche Forschungsgemeinschaft for the Investigation of Health Hazards of Chemical Compounds in the Work Area.
Magnesium oxide, insoluble (Sintermagnesite) (respirable fraction) [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: April 2019

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has reevaluated magnesium oxide. Magnesium oxide, sintermagnesite [
1309‐48‐4
], is a biopersistent granular dust. Therefore, the respirable fraction of magnesium oxide dust has been classified in Carcinogen Category 4 and a MAK value of 0.3 mg/m
3
× material density was established for the respirable fraction in analogy to the other biopersistent granular dusts. Additionally for this fraction the Peak Limitation Category II with an excursion factor of 8 was established. Since magnesium oxide is not systemically distributed and accumulates only locally in the lungs, no developmental effects due to this dust are expected to occur at the MAK value of 0.3 mg/m
3
× material density (respirable, R‐fraction). Magnesium oxide has accordingly been classified in Pregnancy Risk Group C. Magnesium oxide is not designated with either “Sa” or “Sh” or “H”.
1,1,1‐Trichlorethan [MAK Value Documentation in German language, 2019]
Authors: Hartwig A. ,   MAK Commission
Published: April 2019

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the workplace (MAK value) and the Pregnancy Risk Group of 1,1,1‐trichloroethane [
71‐55‐6
].

Critical are pre‐narcotic effects observed in male volunteers exposed at rest to 350 ml/m
3
. The MAK value has now been lowered to 100 ml/m
3
taking into account the increased respiratory volume at the workplace because the blood:air partition coefficient of 1,1,1‐trichlorethane is > 5 (see List of MAK and BAT Values, Section I b and I c). As a systemic effect is critical, Peak Limitation Category II is retained. To avoid short‐term pre‐narcotic effects, the excursion factor of 1 is also retained.

The differences between the MAK value and the NOAECs for developmental toxicity in rats, rabbits and mice are sufficient even taking into account the increased respiratory volume at the workplace. Therefore, damage to the embryo or foetus is unlikely when the MAK value is not exceeded and 1,1,1‐trichloroethane remains assigned to Pregnancy Risk Group C.

1,1,1‐Trichloroethane is neither carcinogenic in rats or mice nor a germ cell mutagen. The designation with “H” (for substances that can be absorbed via the skin in toxicologically relevant amounts) is retained. There are no data on the sensitizing potential in humans. 1,1,1‐Trichloroethane is not a skin sensitizer in guinea pigs.
α‐Aluminiumoxid (α‐Al2O3),Korund (alveolengängige Fraktion) [MAK Value Documentation in German language, 2019]
Authors: Hartwig A. ,   MAK Commission
Published: April 2019

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated α‐aluminium oxide [1344‐28‐1]. α‐Aluminium oxide is a biopersistent granular dust. There are no inhalation studies from which a NOAEC could be derived. Therefore, the respirable fraction of α‐aluminium oxide dust is classified in Carcinogen Category 4 and a maximum concentration at the workplace (MAK value) of 0.3 mg/m3× material density is established for the respirable fraction by analogy with the other biopersistent granular dusts (GBS). As workers are generally exposed to several aluminium species at the workplace, it is recommended that the biological tolerance value (BAT value) for aluminium is also observed. The classification in Carcinogen Category 4 is based on data that showed increased tumour incidences in rats exposed to biopersistent granular dusts in the high dose range. These tumours are regarded as a consequence of the inflammatory mechanism of action, for which a threshold can be defined. Direct genotoxic effects appear to be of subordinate relevance for the carcinogenicity of biopersistent granular dusts. By analogy with biopersistent granular dusts, Peak Limitation Category II is established for α‐aluminium oxide with an excursion factor of 8. Since α‐aluminium oxide is not systemically distributed and accumulates only locally in the lungs, damage to the embryo or foetus is unlikely when the MAK value or the BAT value is not exceeded. α‐Aluminium oxide is classified accordingly in Pregnancy Risk Group C. α‐Aluminium oxide is not expected to be a sensitizer and is not taken up via the skin in toxicologically relevant amounts.
Nanometer Resolved Real Time Visualization of Acidification and Material Breakdown in Confinement
Authors: Merola Claudia , Cheng Hsiu‐Wei , Dworschak Dominik , Ku Ching‐Shun , Chiang Ching‐Yu , Renner Frank Uwe , Valtiner Markus
Published: April 2019

Localized surface reactions in confinement are inherently difficult to visualize in real‐time. Herein multiple‐beam‐interferometry (MBI) is extended as a real‐time monitoring tool for corrosion of nanometer confined bulk metallic surfaces. The capabilities of MBI are demonstrated, and the initial crevice corrosion mechanism on confined nickel and a Ni75Cr16Fe9 model material is compared. The initiation of crevice corrosion is visualized in real time during linear sweep polarization in a 1 × 10−3 m NaCl solution. Pre‐ and post‐experiment analysis is performed to complementarily characterize the degraded area with atomic force microscopy (AFM), optical microscopy, nano‐Laue diffraction (nano‐LD), scanning electron microscopy (SEM)/electron backscatter diffraction (EBSD), and X‐ray photoelectron spectroscopy (XPS). Overall, Ni75Cr16Fe9 displays a better corrosion resistance; however, MBI imaging reveals 200 nm deep severe localized corrosion of the alloy in the crevice opening. Chromium rich passive films formed on the alloy contribute to accelerated corrosion of the confined alloy by a strongly acidifying dissolution of the passive film in the crevice opening. Nano‐LD further reveals preferential crystallographic defect and corrosion migration planes during corrosion. MBI provides nanometer accurate characterization of topologies and degradation in confined spaces. The technique enables the understanding of the initial crevice corrosion mechanism and testing modeling approaches and machine‐learning algorithms.
The Role of Ordering on the Thermoelectric Properties of Blends of Regioregular and Regiorandom Poly(3‐hexylthiophene)
Authors: Lim Eunhee , Glaudell Anne M. , Miller Rachel , Chabinyc Michael L.
Published: April 2019

The thermoelectric properties of semiconducting polymers are influenced by both the carrier concentration and the morphology that sets the pathways for charge transport. A combination of optical, morphological, and electrical characterization is used to assess the effect of the role of disorder on the thermoelectric properties of thin films of poly(3‐hexylthiophene) (P3HT) doped with 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane (F4TCNQ). Controlled morphologies are formed by casting blends of regioregular (RR‐P3HT) and regiorandom (RRa‐P3HT) and then subsequently doped with F4TCNQ from the vapor phase. Optical spectroscopy and X‐ray scattering show that vapor phase doping induces order in the disordered regions of thin films and increases the long‐range connectivity of the film. The thermoelectric properties are assessed as a function of composition and it is shown that while the Seebeck coefficient is affected by structural ordering, the electrical conductivity and power factor are more strongly correlated with the long‐range connectivity of ordered domains.
Asymmetric Direct Remote Michael Addition Reactions of Allyl Furfurals via Dearomative Trienamine and Tetraenamine Catalysis
Authors: Xu Chang‐Jiang , Li Hong‐Wei , He Xiao‐Long , Du Wei , Chen Ying‐Chun
Published: April 2019

2‐Allyl‐3‐furfural could generate dearomative trienamine species in the presence of a chiral secondary amine, and underwent an asymmetric remote ϵ‐regioselective Michael addition reaction with isatin‐derived α,α‐dicyanoalkenes. Meanwhile, the more challenging dearomative tetraenamine intermediate from 5‐allyl‐2‐furfural could be similarly utilized in very remote η‐regioselective Michael additions. In general, good yields with moderate to high enantioselectivity were obtained by employing a concerted activation strategy of bifunctional secondary amine/thiourea catalysts.
Organometallic titanocene complex as highly efficient bifunctional catalyst for intramolecular Mannich reaction
Authors: Wang Yunyun , Jian Yajun , Wu Ya , Sun Huaming , Zhang Guofang , Zhang Weiqiang , Gao Ziwei
Published: April 2019

Bifunctional catalysts bearing two catalytic sites, Lewis acidic organometallic titanocene and Brønsted acidic COOH, have been assembled in situ from Cp2TiCl2 with carboxylic acid ligands, showing high catalytic activity over an intramolecular Mannich reaction towards synthesis of 2‐aryl‐2,3‐dihydroquinolin‐4(1H)‐ones. The determination of the bifunctional catalyst Cp2Ti(C8H4NO6)2 was elucidated by single X‐ray HR‐MS and investigation of catalytic behavior. In particular, masking the Brønsted acidic COOH catalytic site with dormant COOMe lowered the reaction yield greatly, indicating that two catalytic sites work together to maintain high catalytic efficiency.
Improved oxidative biostability of porous shape memory polymers by substituting triethanolamine for glycerol
Authors: Weems Andrew C. , Wacker Kevin T. , Maitland Duncan J.
Published: April 2019

While many aromatic polyurethane systems suffer from poor hydrolytic stability, more recently proposed aliphatic systems are oxidatively labile. The use of the renewable monomer glycerol as a more oxidatively resistant moiety for inclusion in shape memory polymers (SMPs) is demonstrated here. Glycerol‐containing SMPs and the amino alcohol control compositions are compared, with accelerated degradation testing displaying increased stability (time to complete mass loss) as a result of the inclusion of glycerol without sacrificing the shape memory, thermal transitions, or the ultralow density achieved with the control compositions. Gravimetric analysis in accelerated oxidative solution indicates that the control will undergo complete mass loss by approximately 18 days, while lower concentrations of glycerol will degrade fully by 30 days and higher concentrations will possess approximately 40% mass at the same time. In real‐time degradation analysis, high concentrations of glycerol SMPs have 96% mass remaining at 8 months with 88% gel fraction remaining that that time, compared to less than 50% mass for the control samples with 5% gelation. Mechanically, low glycerol‐containing SMPs were not robust enough for testing at three months, while high glycerol concentrations displayed increased elastic moduli (133% of virgin materials) and 18% decreased strain to failure. The role of the secondary alcohol, as well as isocyanates, is presented as being a crucial component in controlling degradation; a free secondary alcohol can more rapidly undergo oxidation or dehydration to ultimately yield carboxylic acids, aldehydes, carbon dioxide, and alkenes. Understanding these pathways will improve the utility of medical devices through more precise control of property loss and patient risk management through reduced degradation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47857.
Manipulating drug release from tridimensional porous substrates coated by initiated chemical vapor deposition
Authors: Ghasemi‐Mobarakeh Laleh , Werzer Oliver , Keimel Roman , Kolahreez Davood , Hadley Peter , Coclite Anna Maria
Published: April 2019

In the recent years, modern wound dressings have attracted much interest to accelerate wound healing processes with the topical delivery of drugs directly on wounds having a significant effect on wound rehabilitation. The objective of this study was to develop a model dressing that would not only provide wound protection from the environment but might also provide the possibility to keep it moist and deliver a drug for potential speeding the healing process. Poly(ethylene terephthalate), cotton fabrics, and polycaprolactone (PCL) nanofibers were used as different tridimensional porous substrates, loaded with a model drug, clotrimazole. The results show that the chemical structure and surface area to volume ratio of the pristine substrates affect the drug release profile. Coating of such substrates by hydrogels poly(2‐hydroxyethyl methacrylate) (p‐HEMA) and poly(methacrylic acid) (p‐MAA) was successfully achieved by initiated chemical vapor deposition. This method was chosen because it is gentle and solventless and most important it can coat free areas within the three‐dimensional structures. Scanning electron microscopy results revealed that p‐HEMA and p‐MAA conformally coated the fibers of the substrates. Moreover, drug release experiments showed that p‐HEMA and p‐MAA coatings provide barriers preventing sudden drug release. In conclusion, our results indicated the possibility of fabricating dressings containing a drug with tunable drug release profile depending on several parameters even though a strong porous structure exists. © 2019 The Authors. Journal of Applied Polymer Science published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47858.
Beyond Average Information: How Q‐Methodology Enhances Course Evaluations in Anatomy
Authors: Brewer‐Deluce Danielle , Sharma Bhanu , Akhtar‐Danesh Noori , Jackson Thomas , Wainman Bruce C.
Published: April 2019

Course evaluations can be used for curriculum improvement and have the potential to better the student learning experience. However, because most are based on Likert scales and open‐ended feedback, understanding diversity in student opinion and uncovering optimal options for course change and improvement are often difficult. Alternatively, Q‐methodology can be used to investigate patterns of thought within a group and may offer greater potential for course reform. This manuscript offers a tutorial‐based explanation of the three components of Q‐methodology studies (1) survey instrument development, (2) data collection, and (3) analysis and interpretation, then demonstrates, via case study, the use of Q‐methodology to evaluate a fourth‐year undergraduate pathoanatomy course. The goal of this article is to enable the reader to broadly apply Q‐methodology in other courses to gain insight and feedback beyond that offered by traditional Likert scale methods. As demonstrated through the pathoanatomy case study, Q‐methodology highlights groups (denoted by factors) of like‐minded students that share opinions, preferences, and values. Overall, Q‐methodology analyses support course instructors in identifying areas of course strength and improvement in an evidence‐based way. This alternative to traditional Likert scales represents a promising solution to ongoing course evaluation limitations.
Insight into the rheological behaviors of a polyanionic collagen fabricated with poly(γ‐glutamic acid)‐NHS ester
Authors: Ding Cuicui , Yang Junhui , Lan Fei , Zheng Zhigong , Dai Libo , Zhang Min
Published: April 2019

The rheological behaviors of a polyanionic collagen, fabricated using poly(γ‐glutamic acid)‐N‐hydroxysuccinimide (γ‐PGA‐NHS) as a novel modifier, were investigated in this study. It was found that both of the native and modified collagen solutions were pseudoplastic fluids, as shown from the steady‐shear tests. While the storage modulus and loss modulus of collagen increased with increasing the amount of γ‐PGA‐NHS, or with increasing the degree of esterification of γ‐PGA‐NHS; meanwhile, the dynamic denaturation temperature determined by dynamic temperature sweep was also increased, indicating an improved thermal stability of collagen solution modified by γ‐PGA‐NHS. The creep–recovery measurements showed that the resistance to deformation was enhanced for modified collagen, probably due to the cross‐linking occurred between the ε‐amino groups of collagen molecules and α‐COOH groups of γ‐PGA‐NHS, as well as the electrostatic interaction and hydrogen‐bond interactions between the two molecules. Furthermore, the aggregation of collagen fibers was promoted due to these interactions between collagen and γ‐PGA‐NHS as observed by atomic force morphology. In addition, the modified collagen exhibited good cytocompatibility as demonstrated by cell growth culturing. The obtained information was expected to give valuable clues to the design and fabrication of controlled stable collagen‐based products for applications in various biomedical fields.
Synthesis, Molecular Properties Prediction and Antimicrobial Activity of Imidazolyl Schiff Bases, Triazoles and Azetidinones
Authors: Rekha Tamatam , Nagarjuna Ummadi , Padmaja Adivireddy , Padmavathi Venkatapuram
Published: April 2019

Benzylidenehydrazinyl imidazoles (3) are prepared from 2‐hydrazinyl imidazoles (2) on treatment with hydrazine. The imine functionality in 3 is utilized to develop 5′‐aryl‐N‐(4‐aryl‐1H‐imidazol‐2‐yl)‐1H‐1,2,3‐triazol‐1‐amines (5) by 1,3‐dipolar cycloaddition of diazomethane followed by aromatization with I2 in DMSO. Compounds 3 are also explored to prepare 4′‐aryl‐1‐(4‐aryl‐1H‐imidazol‐2‐ylamino)‐3‐chloroazetidin‐2‐ones (6) on treatment with chloroacetyl chloride. The Molinspiration calculations predicted that 3, 5 and 6 have molecular hydrophobicity, conformational flexibility, good intestinal absorption and bioactivity scores. The chloro, bromo and nitro substituted imidazolyl azetidinones (6c, 6d, 6f) and nitro substituted imidazolyl triazole (5f) exhibited excellent antibacterial activity on B. subtilis, whereas chloro and nitro substituted imidazolyl triazoles (5c, 5f) showed prominent antifungal activity on A. niger.
VitaFlow™ transcatheter valve system in the treatment of severe aortic stenosis: One‐year results of a multicenter study
Authors: Zhou Daxin , Pan Wenzhi , Wang Jianan , Wu Yongjian , Chen Mao , Modine Thomas , Mylotte Darren , Piazza Niccolo , Ge Junbo
Published: April 2019

Objective

This study reports the 1‐year clinical outcomes of the VitaFlow™ transcatheter aortic valve system in the treatment of severe aortic stenosis.

Background

The VitaFlow™ system (MicroPort®, Shanghai, China) was developed as a novel transcatheter aortic valve replacement system to mitigate or circumvent some of the challenges associated with heavily calcified valves and bicuspid valves.

Methods

From September 2014 to November 2017, a prospective, multicenter, single arm study was conducted in 11 centers in China. The primary end point was all cause mortality at 12 months.

Results

One hundred and ten symptomatic aortic stenosis patients (60 men, 50 women; mean age 77.73 ± 4.78 years) at prohibitive or high risk for surgery were enrolled. Mean society of thoracic surgeons score was 8.84 ± 5.58%. All‐cause mortality was 2.7% at 1‐year. Major stroke, major vascular complication, coronary artery obstruction, new pacemaker implantation occurred in 2.7, 2.7, 1.8, and 19.1% at 1‐year follow‐up, respectively. No patients had moderate or severe paravalvular leak at 1‐year. At 1 year follow‐up, 97% of patients had New York heart association ≤II. Patients with bicuspid valves had similar outcomes as those patients with tricuspid aortic valve stenosis.

Conclusions

The 12‐month clinical results support the safety and efficacy of VitaFlow™ in the treatment of patients with severe aortic stenosis, including patients with bicuspid aortic valve.
Coronary lithotripsy for failed rotational atherectomy, cutting balloon, scoring balloon, and ultra‐high‐pressure non‐compliant balloon
Authors: Venuti Giuseppe , D'Agosta Guido , Tamburino Corrado , La Manna Alessio
Published: April 2019

Calcified and undilatable stenosis still represents a challenge in percutaneous coronary interventions (PCI), due to the higher risk of suboptimal result with consequent worse clinical outcomes. Unfortunately, the dedicated technologies and devices, such as specialized balloon and atherectomy systems, do not always provide adequate plaque modification and optimal vessel preparation allowing optimal stent delivery. The intravascular lithotripsy (IVL) is a technology derived from urology that has been tested in peripheral and coronary calcified plaques, with promising preliminary results. We present a case of a patient undergoing planned PCI of the right coronary artery targeting an undilatable lesion, already resistant to both specialized balloons and rotational atherectomy. Using the IVL system, we were able to break the calcium, guarantying optimal stent expansion with good final result.
Conservatively managed saddle pulmonary embolism
Authors: Kristensen Anna Meta Dyrvig , Rosberg Victoria , Juel Jacob , Pareek Manan
Published: April 2019

Massive, submassive, and nonmassive pulmonary embolism relate to the hemodynamic state, while saddle pulmonary embolus is a purely radiologic term. Patients with saddle embolus often present with hemodynamic compromise. However, treatment depends on the clinical presentation, and stable patients with a saddle pulmonary embolus can respond well to conventional anticoagulation.
Switchable C−H Alkylation of Aromatic Acids with Maleimides in Water: Carboxyl as a Diverse Directing Group
Authors: Pu Fan , Liu Zhong‐Wen , Zhang Lin‐Yan , Fan Juan , Shi Xian‐Ying
Published: April 2019

A ruthenium‐catalyzed protocol to access conjugate addition or decarboxylative conjugate addition of aromatic acids with maleimides has been developed. The reaction shows interesting chemoselectivity with different substituted benzoic acids. The reaction pathway of C−H alkylation is controlled by the intrinsic property of aromatic acids but not reaction conditions. Under almost the same reaction conditions, carboxyl can act as either a classical directing group or a traceless directing group, thereby generating two kinds of products, i. e., 2‐alkyl substituted benzoic acids and alkyl substituted benzenes. These two reactions proceeded under mild and redox‐neutral conditions in neat water under the atmosphere of air, and could be easily scaled up to grams. The decarboxylative conjugate addition, where carboxyl acts as a traceless directing group, can be realized without the addition of any ligand, silver or copper salt.
Enzyme Immobilization in MOF‐derived Porous NiO with Hierarchical Structure: An Efficient and Stable Enzymatic Reactor
Authors: Gao Xia , Ding Yu , Sheng Yude , Hu Mancheng , Zhai Quanguo , Li Shuni , Jiang Yucheng , Chen Yu
Published: April 2019

MOF‐derived porous NiO with hierarchical structure (MHNiO) was prepared based on thermolysis of Ni metal organic framework (Ni‐MOF), which was used as carrier for the immobilization of horseradish peroxidase (HRP) and cytochrome C (Cyt c). The pore size of MHNiO was tuned as 11.8 nm to match the size of free enzyme so as to depress the aggregation of the enzymes in the pore. Meanwhile, the hierarchical structure allowed the substrates concentrated in the vicinity of the enzymes. The obtained enzymatic reactors exhibited better thermal stability, storage stability and reusability. For example, over 83 % of its original activity after 1 h incubation at 70 °C could be remained compared to 18.1 % or 38.4 % remained activity of free HRP and Cyt c, respectively; After 12 cycles of use, over 53 % of original catalytic activity of both the enzymatic reactor could be maintain. The enzymatic kinetic data (Km, Vmax, kcat) and thermodynamic data (Ka, ΔH, ΔS and ΔG) indicated that the improved catalytic performance was attributed to the affinity, selectivity and binding of enzyme to substrate. The two enzymatic reactors could be applied in the fast degradation of 2,4‐dichlorophenol and rifaximin in artificial wastewater, a complete degradation of 2 mg ⋅ mL−1 of 2,4‐dichlorophenol or 20 μg ⋅ mL−1 of rifaximin was achieved in only 20 min.
Electrochemical Ceramic Membrane Reactors in Future Energy and Chemical Process Engineering
Authors: Heddrich Marc P. , Gupta Sanchit , Santhanam Srikanth
Published: April 2019

Electrochemical ceramic membrane reactors (ECMRs) with their unique ability to efficiently couple electrical, chemical, and thermal energy sectors can be a large part of the transition toward renewable energies and defossilized economies. ECMRs utilize ceramic conductors to extract or distribute oxide ions or protons – directly controlled by an external electric current. This article gives an overview of ECMR properties along with the functionalities and advantages. For many reactions, e.g., the direct synthesis of ammonia, ECMRs are not available at the preferred temperature range of 300 – 550 °C. To evidence the possibility of such reactors, functional materials are reviewed. A simple thermodynamic methodology is proposed to determine the suitability of reactions for particular combinations of coupled energy sectors.
Consistency and reproducibility of next‐generation sequencing in cytopathology: A second worldwide ring trial study on improved cytological molecular reference specimens
Authors: Pisapia Pasquale , Malapelle Umberto , Roma Gianluca , Saddar Sonika , Zheng Qi , Pepe Francesco , Bruzzese Dario , Vigliar Elena , Bellevicine Claudio , Luthra Rajyalakshmi , Nikiforov Yuri E. , Mayo‐de‐Las‐Casas Clara , Molina‐Vila Miguel Angel , Rosell Rafael , Bihl Michel , Savic Spasenija , Bubendorf Lukas , de Biase Dario , Tallini Giovanni , Hwang David H. , Sholl Lynette M. , Vander Borght Sara , Weynand Birgit , Stieber Daniel , Vielh Philippe , Rappa Alessandra , Barberis Massimo , Fassan Matteo , Rugge Massimo , De Andrea Carlos E. , Lozano Maria D. , Lupi Cristiana , Fontanini Gabriella , Schmitt Fernando , Dumur Catherine I. , Bisig Bettina , Bongiovanni Massimo , Merkelbach‐Bruse Sabine , Büttner Reinhard , Nikiforova Marina N. , Roy‐Chowdhuri Sinchita , Troncone Giancarlo ,   the Molecular Cytopathology Meeting Group
Published: April 2019

Background

Artificial genomic reference standards in a cytocentrifuge/cytospin format with well‐annotated genomic data are useful for validating next‐generation sequencing (NGS) on routine cytopreparations. Here, reference standards were optimized to be stained by different laboratories before DNA extraction and to contain a lower number of cells (2 × 105). This was done to better reflect the clinical challenge of working with insufficient cytological material.

Methods

A total of 17 worldwide laboratories analyzed customized reference standard slides (slides A‐D). Each laboratory applied its standard workflow. The sample slides were engineered to harbor epidermal growth factor receptor (EGFR) c.2235_2249del15 p.E746_A750delELREA, EGFR c.2369C>T p.T790M, Kirsten rat sarcoma viral oncogene homolog (KRAS) c.38G>A p.G13D, and B‐Raf proto‐oncogene, serine/threonine kinase (BRAF) c.1798_1799GT>AA p.V600K mutations at various allele frequencies (AFs).

Results

EGFR and KRAS mutation detection showed excellent interlaboratory reproducibility, especially on slides A and B (10% and 5% AFs). On slide C (1% AF), either the EGFR mutation or the KRAS mutation was undetected by 10 of the 17 laboratories (58.82%). A reassessment of the raw data in a second‐look analysis highlighted the mutations (n = 10) that had been missed in the first‐look analysis. BRAF c.1798_1799GT>AA p.V600K showed a lower concordance rate for mutation detection and AF quantification.

Conclusions

The data show that the detection of low‐abundance mutations is still clinically challenging and may require a visual inspection of sequencing reads to detect. Genomic reference standards in a cytocentrifuge/cytospin format are a valid tool for regular quality assessment of laboratories performing molecular studies on cytology with low‐AF mutations.
Investigating color appearance in optical see‐through augmented reality
Authors: Hassani Nargess , Murdoch Michael J.
Published: April 2019

Color appearance for real objects has been studied over decades and it has been well modeled. However, in augmented reality (AR) environments, virtual content is added to a real background and a mixed appearance is perceived. In this research, we studied color appearance in AR and investigated the applicability of the CAM16 color appearance model, one of the most comprehensive current color appearance models, in an AR environment. Using a benchtop optical mixing apparatus as an AR simulator, objective measurements of mixed colors in AR were performed. Then a psychophysical color matching experiment was performed with combinations of mixed foreground and background colors. The results showed that CAM16 is not accurate in predicting the color appearance in AR environment; therefore, it was modified with the addition of chromatic simultaneous contrast, resulting in an improved fit to the AR experiment data. A second psychophysical color matching experiment was performed on a single display to compare the color perception in AR with color perception in real world from a single display.
Use of Serine/Threonine Ligation for the Total Chemical Synthesis of HMGA1a Protein with Site‐Specific Lysine Acetylations
Authors: Liu Heng , Liu Han , Li Xuechen
Published: April 2019

High‐mobility‐group (HMG) proteins are a class of abundant non‐histone nuclear proteins, among which HMGA1a is well‐known for its association with transcription regulation as well as tumor formation and disease development. To study the functions of post‐translational modifications, homogeneous HMGA1a protein with site‐specific lysine acetylations (64/66/70/73) has been chemically synthesized. The full‐length HMGA1a protein was assembled through two Ser/Thr ligations of three peptide fragments at Gly37‐Thr37 and Thr75‐Thr76 sites, respectively. Further in vitro studies with chemically synthesized proteins suggested that these acetylations did not significantly affect the CK2‐catalyzed phosphorylation on the HMGA1a acidic tail.
Tandem Systems for Two‐Photon Uncaging of Bioactive Molecules
Authors: Klausen Maxime , Dubois Victor , Verlhac Jean‐Baptiste , Blanchard‐Desce Mireille
Published: April 2019

Photodeprotection of biological ligands with the combination of photolabile protecting groups (PPGs) and two‐photon (2P) excitation techniques offers the possibility to control physiological phenomena with utmost spatial and temporal precision. Yet, designing PPGs with sufficient 2P photosensitivity still remains challenging. Direct enhancement of the 2P absorption properties usually relies on modifications of the PPG structure, which sometimes results in unpredictable and counterproductive effects on the uncaging quantum yield. In that respect, combining known PPGs with a suitable two‐photon light‐harvesting antenna within a modular architecture offers a promising alternative. In this Minireview, we highlight this versatile strategy, with a discussion of different tandem 2P uncagers, relying on photoinduced electron transfer (PET), triplet‐ energy transfer (TT‐ET), or Förster resonance energy transfer (FRET) sensitization to enhance the 2P sensitivity of PPGs.
Unravelling the Aptamer‐Analyte Interaction Dynamics through Fluorescence Quenching in Graphene Quantum Dots (GQDs) Based Homogeneous Assays
Authors: Ang Wei Li , Bonanni Alessandra
Published: April 2019

Graphene quantum dots (GQDs) are used here as a biosensing platform for the recognition of the major food contaminant ochratoxin A (OTA), with a fluorescently labelled DNA aptamer (FAM OTA aptamer) functioning as the biorecognition element. The detection principle lies in the formation of noncovalent interactions between the FAM OTA aptamer and the GQD surface, and the consequent fluorescence quenching. The further change in the fluorescence signal, induced by the formation of the FAM OTA Aptamer/OTA conjugate during the detection step, could then be correlated to the presence and concentration of the target analyte. Upon tuning the concentration of GQDs, a switch in the biorecognition mechanism occurred. Specifically, while a lower GQD concentration (0.060 mg/mL) resulted in a restoration of the fluorescence intensity upon incubation with OTA, a higher GQD concentration (0.150 mg/mL) provided a further quenching of the final fluorescence intensity. Upon further calibration study, it was discovered that the latter mechanism provided a better option in terms of linearity of response, detection limit and selectivity.
Tuning the Luminescent Properties of Ruthenium(II) Amino‐1,10‐Phenanthroline Complexes by Varying the Position of the Amino Group on the Heterocycle
Authors: Abel Anton S. , Zenkov Ilya S. , Averin Alexei D. , Cheprakov Andrey V. , Bessmertnykh‐Lemeune Alla G. , Orlinson Boris S. , Beletskaya Irina P.
Published: April 2019

Eight 1,10‐phenanthrolines bearing one or two 2‐(1‐adamantyloxy)ethylamino substituents attached to different positions of the heterocyclic core were prepared according to SNAr or palladium‐catalyzed amination reactions. Their reaction with cis‐Ru(bpy)2Cl2 (bpy=2,2’‐bipyridine) was investigated and Ru(bpy)2(L)(PF6)2 (phen=1,10‐phenanthroline) (L=amino‐substituted 1,10‐phenanthroline) complexes were obtained in good yields. The electronic structure and emissive properties of these complexes are strongly dependent on the position of the amino substituent in the heterocycle. Emission bands of the complexes bearing 2‐ and 4‐substituted 1,10‐phenanthroline ligands are red‐shifted (up to 56 nm) and less intense compared to that of the parent [Ru(phen)(bpy)2](PF6)2. In contrast, the introduction of the substituent in 3‐ or 5‐position of 1,10‐phenanthroline ring induces only small decrease of luminescence and the brightness of the complex with the 3‐substituted ligand is comparable to that of the parent complex.
Strategic responses of stigmatized Chinese manufacturing firms to formal and informal environmental regulative pressures through enhanced corporate social responsibility effort
Authors: Xu Jia , Wei Jiuchang , (Allan) Chen Haipeng
Published: April 2019

Linking two forms of regulative pressures to different motivations for firms' strategic choices, we propose that stigmatized firms' effort to enhance their corporate social responsibility (CSR) reflects legitimacy considerations when faced with formal regulative pressures, but efficiency considerations when faced with informal regulative pressures. We provide empirical support for our theory by investigating publicly listed Chinese manufacturing firms' environmental CSR performance after they are stigmatized for environmental pollution. Our data strongly support our predictions. Stigmatized firms show a lower CSR effort when formal regulative pressure is low and they can easily shun responsibility for polluting the environment, whereas they show a higher CSR effort when informal regulative pressure is high and they cannot easily shun responsibility for the pollution. These findings highlight the unique insight that can be gained by studying stigmatized firms' reactions to different types of regulative pressures as a function of responsibility dilution in an emerging economy.