bluuebunny/crossref_metadata_2025 huggingface dataset:
A penalized regression approach for DNA copy number study using the sequencing data
Authors: Lee Jaeeun , Chen Jie
Published: May 2019

Modeling the high-throughput next generation sequencing (NGS) data, resulting from experiments with the goal of profiling tumor and control samples for the study of DNA copy number variants (CNVs), remains to be a challenge in various ways. In this application work, we provide an efficient method for detecting multiple CNVs using NGS reads ratio data. This method is based on a multiple statistical change-points model with the penalized regression approach, 1d fused LASSO, that is designed for ordered data in a one-dimensional structure. In addition, since the path algorithm traces the solution as a function of a tuning parameter, the number and locations of potential CNV region boundaries can be estimated simultaneously in an efficient way. For tuning parameter selection, we then propose a new modified Bayesian information criterion, called JMIC, and compare the proposed JMIC with three different Bayes information criteria used in the literature. Simulation results have shown the better performance of JMIC for tuning parameter selection, in comparison with the other three criterion. We applied our approach to the sequencing data of reads ratio between the breast tumor cell lines HCC1954 and its matched normal cell line BL 1954 and the results are in-line with those discovered in the literature.
Das strategische Langfrist-Problem der NATO
Authors: Kamp Karl-Heinz
Published: May 2019

Siebzig Jahre nach ihrer Gründung ist die NATO in guter Verfassung und gilt mit Recht als die erfolgreichste Sicherheitsorganisation in der neueren Geschichte. Mittel- und langfristig sieht sie sich allerdings einer existenziellen Herausforderung ausgesetzt, da es immer schwerer werden wird, ihre Relevanz für die Vereinigten Staaten als Bündnisvormacht zu bewahren. Dieses Problem ergibt sich weniger aus der bündnisfeindlichen Politik Donald Trumps, sondern folgt aus der sich abzeichnenden geostrategischen Re-Orientierung der USA weg von Russland und hin zu China. In einer möglichen bipolaren Welt mit China und USA als Konkurrenten wird auch die NATO sich geographisch stärker in den asiatisch-pazifischen Raum orientieren müssen, wenn sie nicht dramatisch an Bedeutung verlieren will.
The development of person agreement and the cliticization of personal pronouns in Batsbi
Authors: Kojima Yasuhiro
Published: May 2019

Most Nakh-Daghestanian languages have gender (or noun class) agreement in the verb, but do not have person agreement. This is the case with Chechen and Ingush, which are genetically the closest to Batsbi. Batsbi, by contrast, has developed person agreement with the subject in the verb along with gender agreement. This is assumed to be due to the strong influence of Georgian, which has long been the second language of Batsbi speakers. In Georgian, the verb shows person agreement with the subject as well as with the direct or indirect object. Present-day Batsbi, presumably inspired by the polypersonal agreement of Georgian, further develops the cliticization of non-subject personal pronouns. To put it simply, it seems as though Batsbi attempts to express what a Georgian verb may encode in a single, finite form by means of a verb and a personal pronoun that is cliticized to it.
Measurement uncertainty in laboratory medicine: the bridge between medical and industrial metrology
Authors: Coskun Abdurrahman , Berçik İnal Berrin , Serdar Muhittin
Published: May 2019

Uncertainty is an inseparable part of all types of measurements, that is, in metrology a measurement without uncertainty is not possible. Calculation of uncertainty increases the awareness of the certainty of measurement results. Reporting measurement uncertainty is mandatory in almost all industrial sectors but not in laboratory medicine. Test results without analytical uncertainty increases the diagnostic uncertainty, causing errors that could seriously affect patients health. To improve diagnostic certainty, we should calculate and upon request report measurement uncertainty to laboratory users (ISO 15189). In this mini-review, we summarized the theoretical perspective of uncertainty concept, its relation to Six Sigma and finally compared it with Total Error Method.
Synthesis and crystal structure of a series of stoichiometric (n)-ITB molybdenum-bronze oxides containing trivalent arsenic
Authors: Goudjil Meriem , Gutiérrez-Puebla Enrique , Bonazzi Paola , Lunedei Eugenio , Mezaoui Djillali , Bindi Luca
Published: May 2019

A series of six new single crystals of fully stoichiometric As3+-bearing Mo-oxides and partially W-substituted Mo-oxides with formula As
m
O(Mo1−

x
W
x
O3)
p
(m = 1, 2; p = 5, 7, 9, 10 and 11 and 0 ≤ x ≤ 0.6) was successfully grown using vapor-phase transport in vacuo. The crystal structures were determined using single-crystal X-ray diffraction data. All these compounds exhibit acentric orthorhombic symmetry with Z = 2, and belong to the so-called (n)-ITB (intergrowth tungsten bronzes) family, with n = 2, 3, 4 and 5. The six (n)-ITB phases have the following formulae: (2)-AsMo5O16 (Pm 2a), (2)-As2Mo10O31 (Pma 2), (3)-AsMo7O22 (Pmn 21), (3)-As(Mo5.53W1.47)O22 (Pmn 21), (4)-As(Mo4.33W4.67)O28 (Pm 2a) and (5)-As(W6.63Mo4.37)O34 (Pmn 21). Their structures consist of vertex-sharing MO6 octahedral units (with M either Mo or Mo/W) connected so as to form three-dimensional frameworks. Such frameworks consist of perovskite tungsten bronzes (PTB) type slabs, from 2- to 5-octahedra wide, intergrown with single hexagonal tungsten bronzes (HTB) type slabs, stacked up to form pseudo-hexagonal tunnels along the a-axis. As3+ and additional oxygen atoms are located in off-center positions inside the tunnels, forming As–O bonds with peculiar arrangements. In particular, we obtained the first examples of structures where, besides the usual AsO3E distorted pyramidal geometry, As3+ adopts AsO4E coordination with a seesaw configuration.
Insight into the Structural, Electronic, Elastic, Mechanical, and Thermodynamic Properties of XReO3 (X = Rb, Cs, Tl) Perovskite Oxides: A DFT Study
Authors: Zhao Song , Wei Zhongbin , Dar Sajad Ahmad
Published: May 2019

In the present work, perovskite oxides XReO3 (X = Rb, Cs, Tl) have been reported using density functional theory (DFT) for structural, electronic, mechanical, elastic, and thermodynamic properties. Structural optimization has been carried out using local density approximation (LDA) and generalized gradient approximation (GGA) in the scheme of Perdew, Burke, and Ernzerhof. Electronic properties have been calculated using GGA, and all the three materials were found to have metallic nature. From the elastic constants, all the three compounds were found mechanically stable in cubic structure. Poisson’s ratio (ν), Cauchy’s pressure (C
12–C
44) and Pugh ratio (B/G) present the ductile nature of RbReO3 and TlReO3, whereas CsReO3 was found to establish a brittle nature. These compounds were found to have an elastically anisotropic nature. The calculated melting temperatures were found to be 2851 ± 300, 2814 ± 300, and 2924 ± 300 K, respectively, for XReO3 (X = Rb, Cs, Tl). Using quasi-harmonic Debye approximation, we have calculated the pressure- and temperature-dependent variation in cell volume, bulk modulus, Debye temperature, and specific heat capacity.
Konflikt als Movens – Chancen für Schule, Religion und Demokratie
Authors: Engelmann Sebastian
Published: May 2019

In times of antidemocratic resentment and rising societal diversity, harmony and unity become questionable as the normative foundation for modern approaches to education. This article makes plausible the assertion that educational thought needs to change one of its basic theoretical assump- tions: the overall perception of conflicts. In a first step, the article introduces the concept of the “School Republic”, summarizing the ideas of Hermann Lietz and then its advancements by Minna Specht. In a second step, the article ties this specific pedagogical arrangement to recent political theory and one well-known concept of human rights education. Finally, the article discusses the scope of the approach which is sketched out here and identifies links to recent discussions in democraticcy education.
Religionsunterricht als Beitrag zur Bildung in der Demokratie
Authors: Grümme Bernhard
Published: May 2019

In responding to critical phenomenona such as populism and fake news, democracy depends on democratic education, especially in times of post-democracy (Colin Crouch). In this context, religious education is necessary as well. It represents a political dimension with a defined option for the outcast, the suffering, the “Other”. The aim of the following observations is to justify, disclose, and establish this dimension. By reflecting on different concepts of political education in their theological as well as, religious-educational contours, the specific critical-constructive value of religious development and education on behalf of and conducive to an even more democratising society will be outlined and emphasized.
“Best of both worlds”: A students-as-partners near-peer moderation program improves student engagement in a course Facebook group
Authors: Jay Mohammad , Lim Michelle , Hossain Khalid , White Tara , Naqvi Syed Reza , Chien Kevin , Haffie Tom
Published: May 2019

Social media platforms like Facebook are designed to facilitate online communication and networking, primarily around content posted by users. As such, these technologies are being considered as potential enhancements to traditional learning environments. However, various barriers to effective use may arise. Our research investigated the effectiveness of a students-as-partners near-peer moderation project, arising from collaboration between instructors and senior students, as a vehicle for enhancing student interaction in a Facebook group associated with a large introductory science course. The quantity and quality of sample posts and comments from Facebook groups from three successive academic years were evaluated using a rubric that considered characteristics such as civility, content accuracy, critical thinking and psychological support. Two of these groups were moderated by near-peer students while the third group was not moderated.  We found improved course discussion associated with moderated groups in addition to benefits to moderators and the faculty partner. This suggests that near-peer moderation programs working in collaboration with faculty may increase student engagement in social media platforms.
“More than just a student”: How co-creation of the curriculum fosters third spaces in ways of working, identity, and impact
Authors: Lubicz-Nawrocka Tanya Michelle
Published: May 2019

The Third Space (Bhabha, 2004) represents non-traditional roles, processes, relationships, and spaces in which individuals work and have impact. This article presents qualitative research into 13 different curriculum co-creation initiatives at five Scottish universities and analyses the forms of Third Space that emerge.The findings highlight that curriculum co-creation can foster Third Spaces that include: new ways of working in learning and teaching, student development in a space between traditional student and teacher roles and identities, and impact in civic engagement within and beyond the university. The respect and reciprocity that characterise curriculum co-creation can greatly benefit students’ personal and professional development as individuals. In addition, I suggest that the Third Space of civic engagement can advance the Third Mission of universities (beyond impact in the first two missions of teaching and research) when students and teachers work in partnership to have a positive effect on the wider society.
Third space partnerships with students: Becoming educational together
Authors: Burns Tom , Sinfield Sandra Frances , Abegglen Sandra
Published: May 2019

This case study discusses how we harnessed a University Teaching Fellowship to open a collective third space partnership with “non-traditional” students to enable them to draw on their experiences of transition into higher education and to produce resources designed to help other students find their place, voice, and power at university. We discuss first the “in-between” opportunities of learning development as a “third space profession” that enables us to work in creative partnership with students. We further set the scene by exploring the third space potential of learning development per se and then examine the successful development and administration of a learning development module, Becomingan Educationist, at a medium-sized university in the United Kingdom.We conclude by arguing for third space partnerships not just alongside the curriculum, but in and through the curriculum as well.
Adaptive Process Control for Uniform Laser Hardening of Complex Geometries Using Iterative Numerical Simulation
Authors: Barath V. R. , Tak Manish , Padmanaban R. , Padmanabham G.
Published: May 2019

Laser surface hardening, when applied to complex geometries, poses a challenge in the terms of obtaining uniform hardness throughout the hardened area because of variable heat sink effects. In this work, an iterative numerical approach was used to estimate the required modulation in laser power to achieve a uniform surface temperature throughout the process zone. Firstly, a transient thermal model for the laser–material interaction was developed using the finite element method for a rectangular spot of 8 × 5 mm. The temperature-dependent material properties were used to bring in nonlinear effects in the analysis so as to predict the hardened zone dimensions more precisely. The numerical model was validated by carrying out laser hardening experiments using a 6-kW diode laser. The validated numerical model was used with an iterative technique aided by conditional looping to achieve a uniform surface temperature during the laser hardening of the complex geometry with a variable heat sink. The developed iterative approach can be effectively used on any geometry with a variable heat sink to obtain a constant surface temperature throughout the process zone.
Authentic Dishes, Staged Identities: Thailand's Cooking Schools for Tourists
Authors: Mills Mary Beth
Published: May 2019

In Thailand today local cooking-school classes are a popular attraction on many tourist itineraries. Moreover, these experiences almost always prompt rave reviews from international visitors: “It was so much fun!” But why are cooking school classes fun? And what does this pleasure tell us about the cultural logics of authenticity in Thai culinary tourism and, more generally, about the commodification of food and identity in the contemporary global economy? Drawing on ethnographic observation in two of Thailand's primary tourist destinations, Bangkok and Chiang Mai, this article explores how cooking schools' claims to cultural authenticity intertwine with participants' experiences of playful entertainment. The ways in which cooking schools mobilize these dynamics illuminate the complex production and consumption of hierarchies of value within the global experience economy. On the one hand, Thailand's insertion within transnational circuits of touristic mobility and cosmopolitan desire has made the creative strategies of recreational cooking schools possible as well as potentially lucrative. On the other hand, the encounters schools stage between Thai and tourist participants remain framed by appetites for exotic cultural difference that ultimately reflect and reproduce global hierarchies of power and privilege.
Blood, Sweat, and Tweezers: The Morality of Food Photography
Authors: Macey Dan
Published: May 2019

A commercial food stylist comes to terms with the morality and ethics of having animals slaughtered for the sake of photographing them. The issue is addressed in the context of broader food waste issues surrounding the business of photographing food for commercial advertising purposes.
Effect of low-dose tungsten on human thyroid stem/precursor cells and their progeny
Authors: Gianì Fiorenza , Pandini Giuseppe , Scalisi Nunzio Massimo , Vigneri Paolo , Fazzari Carmine , Malandrino Pasqualino , Russo Marco , Masucci Romilda , Belfiore Antonino , Pellegriti Gwabriella , Vigneri Riccardo
Published: May 2019

Thyroid cancer incidence is increased in volcanic areas where environment pollution biocontaminates residents. Tungsten (W) is the most increased heavy metal in drinking water of Mount Etna volcanic area where it exceeds the normal range in the urine of 27% inhabitants. The possible connection between increased tungsten and thyroid cancer has never been studied. We investigated in vitro the effect tungsten on both human thyrocytes in primary culture, thyrospheres (aggregates of stem/precursor thyroid cells) and thyrocytes differentiated from tungsten-exposed thyrospheres. Chronic exposure to low-dose (nanomolar range, as in the urines of volcanic area residents) soluble tungsten had major biological effects on thyroid stem/precursor cells, promoting growth with a biphasic (hormetic) dose-response and reducing apoptosis. No such effects were observed in mature thyrocytes. In addition, tungsten-exposed thyrospheres had abnormal expression of genes commonly altered also in thyroid cancer and increased activation of the DNA-repair proteins H2AX and 53BP1. Moreover, exposure to tungsten decreased thyrosphere differentiation, as indicated by the reduced expression of thyroid-specific genes in derived thyrocytes that also showed preneoplastic changes such as increased anchorage-independent growth, clonogenic growth and migration capacity. The mechanism of action of tungsten on thyroid stem/precursor cells is unclear but involves membrane G-proteins and activation of the ERK signaling pathway. These data indicate that chronic exposure to slightly increased tungsten, harmless for mature thyrocytes, importantly affects the biology of stem/precursor thyroid cells and of their progeny, inducing characteristics of preneoplastic transformation.
Minimization of Dose Load in Algorithms of X-Ray Computed Tomography
Authors: Bulavin L. A. , Zabashta Yu. F. , Motolyha O. V.
Published: May 2019

An algorithm has been developed for the reconstruction of an X-ray image obtained at the minimum dose load on the researched object and provided a given image accuracy. This algorithm combines approaches typical of the inverse projection and regularization methods. The image is formed by overlaying filtered projections, and the filtering parameters are determined from the minimum condition for the difference between the discrepancy and the experimental error.
Effects of Brownian Motions on Electrical Conductivity and Optical Transparency of Two-Dimensional Films Filled by Needle-Like Particles
Authors: Mazur L. O. , Bulavin L. A. , Vygornitskii N. V. , Lebovka N. I.
Published: May 2019

The effects of Brownian motions on the electrical conductivity and optical transparency of two-dimensional films filled with needle-like particles (needles) have been investigated, using the Monte-Carlo method. The initial state of the system was produced with the use of the random-sequential adsorption process. In the subsequent evolution (aging) of the system, the translation and rotation diffusion motions are taken into account. The intersections between needles are forbidden. The interaction potential between needles is short-range (i.e., it is nonzero at distances less than Rc) and is dependent on the angle between needles ф(∝ cos2 ф). The aging results in the formation of island, net-like, and hole-like (with significant cavities) structures depending on parameters of the interaction potential. The relations between the electrical conductivity and the optical transparency during the aging are discussed.
Degradasi Zat Warna Orange-F3R dan Violet-3B secara Sonolisis Frekuensi Rendah dengan Penambahan Katalis C-N-Codoped TiO2
Authors: Putri Reza Audina , Safni Safni , Wellia Diana Vanda , Septiani Upita , Jamarun Novesar
Published: May 2019

Zat warna orange-F3R dan violet-3B merupakan zat warna organik sintetis turunan vat yang bersifat non-biodegradable. Degradasi kedua zat warna ini telah dilakukan secara sonolisis dengan penambahan katalis semikonduktor TiO2 anatase yang didoping karbon dan nitrogen. Proses sonolisis menggunakan iradiasi ultrasonik dengan frekuensi 35 kHz. Massa katalis optimum yang diperoleh untuk sonolisis zat warna orange-F3R adalah 9 mg dan 6 mg untuk violet-3B. Persen degradasi meningkat secara signifikan dengan penambahan katalis yaitu dari 8.3% menjadi 36.2% untuk sonolisis zat warna orange-F3R selama iradiasi 180 menit. Sedangkan, dengan waktu iradiasi yang sama persen degradasi dari zat warna violet meningkat dari 5.8% menjadi 34.2% setelah penambahan katalis. Kata kunci: C-N-codoped TiO2, sonolisis, ultrasonik, vat  Orange-F3R and violet-3B are non-biodegradable synthetic organic dyes. The degradation of these two dyestuffs has been done by sonolysis process with the addition of semiconductor TiO2 anatase catalyst which is doped by carbon and nitrogen atoms. The sonolysis process used ultrasonic irradiation with a frequency of 35 kHz. The optimum catalyst mass obtained for the orange-F3R dye sonolysis was 9 mg and 6 mg for violet-3B. The percentage of degradation increased significantly with the addition of the catalyst; it was from 8.3% to 36.2% for the orange-F3R dye during irradiation for 180 min. Meanwhile, by the same irradiation time, the degradation percentage of violet dye increased from 5.8% to 34.2% after the addition of the catalyst. Keywords: C-N-codoped TiO2, sonolysis, ultrasonic, vat-dye.
SiO2 Entrapment of Animal Cells for Hybrid
Bioartificial Organs
Authors: Carturan Giovanni , Dal Monte Renzo , Muraca Maurizio
Published: May 2019

Si-alkoxides in gas phase are reactive towards the surface of animal cells,
depositing a homogeneous layer of porous silica. This encapsulation method
preserves cell viability and does not alter the hindrance of the biological
load.

In the prospective use for the design of a hybrid bioartificial liver,
hepatocytes in a collagen matrix can be entrapped by the siliceous deposit
which provides definite mechanical stability to the collagen matrix and
molecular cutoff vs. high molecular weight proteins, including
immunoglobulins. The functionality of the encapsulated cell load is
maintained for the expressions of typical liver and pancreas metabolic
activities.
Polymer Crystallization Studied in Confined Dimensions using
Nanocomposites from Polymers and Layered Minerals
Authors: Kuchta Frank-Dieter , Lemstra Piet J. , Keller Andrew , Batenburg Lawrence F. , Fischer Hartmut R.
Published: May 2019

Polymer-layered silicate nanocomposites from polyamide-11 (PA-11) were
prepared and the morphology and properties have been investigated in order
to link the fundamental research field of polymer crystallization with the
technical important field of composite materials. Semi-crystalline polymers
are known to crystallize in different phases (e. g. monoclinic, hexagonal)
forming chain-folded lamellar crystals. Depending on experimental conditions
(e. g. temperature, pressure) the crystal size (lamellar thickness) affects
the stability of these phases. The incorporation of layered silicates acting
as hard walls into semi-crystalline polymers opens new possibilities to: i)
study polymer crystallization in confined dimensions, and ii) provide
materials from commodity or engineering polymers with enhanced properties.
The effect of an external confinement introduced by highly anisotropic
silicate layers of organically modified clay minerals on crystal growth and
nanocomposite properties has been studied. The composites are prepared by in
situ polycondensation of polyamides and/or blending via melt extrusion. The
nanocomposites exhibit a homogeneous distribution of individual silicate
layers at low clay contents. The lamellar thickening growth is reduced in
polyamide crystallization due to the external constrained of the silicate
layers in the host polymer. Furthermore these nanocomposites show a slightly
enhanced thermal stability, tensile modulus and an increased elastic
behavior over a broader temperature range. No distinct glass transition has
been observed at highest clay contents.
Microstructure and Physical Properties of Clay-Polymer
Composites
Authors: Blanton T.N. , Majumdar D. , Melpolder S.M.
Published: May 2019

Clay-polymer nanoparticulate composite materials are evaluated by the X-ray
diffraction technique. The basal plane spacing provided information about
the degree of intercalation and exfoliation of the 2: 1 layered clay
structure. Both intercalation and exfoliation are controlled by the identity
of the polymer and the clay:polymer ratio.
Stiffness Improvements and Molecular Mobility in Epoxy-Clay
Nanocomposites
Authors: Kornmann X. , Berglund L. A. , Lindberg H.
Published: May 2019

Conventional composites filled with clay as well as intercalated
nanocomposites, and exfoliated nanocomposites based on a glassy epoxy matrix
have been synthesised. Flexural moduli of these materials were measured in
three-point bending at various clay contents. For a given clay content,
stiffness improvements depended not only on the dispersion of the clay on
the microscale, but also on the exfoliation of the clay layers at the
nanolevel. Dynamic mechanical measurements indicated a decrease of intensity
in the glass transition peak with the extent of exfoliation of the clay and
the clay content, suggesting a restriction of the molecular mobility of the
polymer in the vicinity of the clay layers. A shift in Tg of 20°C towards
lower temperature for the epoxy resin cured at 160°C was possibly caused by
thermal degradation of compatibilizing agents at high temperature.
Inorganic-Organic Hybrid Polymers from Surface-Modified
Oxometallate Clusters
Authors: Schubert Ulrich , Trimmel Gregor , Moraru Bogdan , Tesch Walter , Fratzl Peter , Gross Silvia , Kickelbick Guido , Hüsing Nicola
Published: May 2019

Inorganic-organic hybrid polymers were prepared by radical polymerization of
methacrylic acid or methyl methacrylate with the (meth) acrylate-substituted
oxozirconium and oxotitanium clusters
Zr6(OH)4O4(OMc)12(OMc =
methacrylate), Zr4O2(OMc)12,
Ti6O4(OEt)8(OMc)8 and
Ti4O2(OPri)6(OAcr)6(OAcr
= acrylate). A few mol% of cluster is sufficient for an efficient
cross-linking of the polymer chains. Small-angle X-ray scattering data
indicate that the cluster size is retained in the polymers and that the
microstructure of the cluster cross-linked samples can be described by a
dispersion of identical spherical or disk-shaped clusters in the polymer.
The obtained hybrid polymers exhibit a higher thermal stability because
depolymerization reactions are inhibited. Contrary to undoped poly (methyl
methacrylate), the cluster cross-linked polymers are insoluble but swell in
organic solvents. The solvent uptake upon swelling decreases with an
increasing amount of polymerized cluster.
Hybrid silica / polymer nanoparticles through emulsion
polymerization
Authors: Bourgeat-Lami Elodie , Luna-Xavier Jose-Luiz , Guyot Alain
Published: May 2019

Polymer encapsulation of inorganic silica nanoparticles was performed
through emulsion polymerization of styrene and methyl methacrylate monomers.
Two different approaches are described. In a first one, the hydrophilic
silica was modified by reacting the coupling agent, 3-trimethoxysilyl propyl
methacrylate, which was involved further in propagation reactions. In a
second approach, we used the 2–2'- azobis (2-amidinopropane) dihydrochloride
cationic initiator to promote interactions of the positively charged growing
polymer with the negatively charged silica surface. We demonstrate, using
transmission electron microscopy, that the silica beads are successfully
encapsulated by the two techniques giving silica/polymer nanoparticles with
different morphologies. The influence of some parameters, such as the nature
of the surfactant and the monomer concentration, on the efficiency of the
encapsulation reaction and the morphology of the encapsulated products are
reported.
Dendritic and Multipodal Liquid-Crystalline Materials based on
Silsesquioxane and Siloxane Cores
Authors: Mehl Georg H. , Elsäβer Ralf , Shepperson Keith J. , Thornton Adam , Goodby John W.
Published: May 2019

In recent years great advances have been made in the synthesis of
organic-inorganic hybrid materials, whether they are oligomeric, multipodal,
polymeric or dendritic in structure. Of particular interest are
liquid-crystalline systems, as the control of the soft self-assembly
behaviour of these systems allows for the addressing of the macroscopic
properties of these materials.

The investigations of silsesquioxane and siloxane cores decorated with
suitable organic groups of linear and branched structures leading to
liquid-crystalline phase behaviour is presented. The structural and chemical
features which govern the phase behaviour will be discussed. Important
features are the size, geometry, structure and flexibility of the inorganic
core, the flexibility, branching and length of the spacer linking inorganic
cores and the organic groups, which promote liquid-crystalline phase
behaviour. The effects of a variety of mesogenic structures on the
liquid-crystalline phase behaviour and stability range will be
discussed.
Structural Evolution of Silsesquioxane-based Organic/Inorganic
Nanocomposite Networks
Authors: Soles Christopher L. , Lin Eric K. , Wu Wen-li , Zhang Chunxin , Laine Richard M.
Published: May 2019

The basic tetrahedra of silica are readily assembled into eight cornered
cages known as cubic silsesquioxanes ([RSiO1.5]8).
Silsesquioxane cubes represent one of the smallest possible units of ceramic
silica. The corners of these nanometer-sized ceramic cubes are readily
functionalized with reactive groups and incorporated into organic polymers.
In this work, we characterize the structures that result from varying the
length of the flexible organic segments used to connect the cubes in a
series of hybrid network materials. For very short organic segments, steric
hindrances inhibit high degrees of network conversion and the resulting
network is very inhomogeneous. As the length of the flexible organic segment
increases, the added degrees of freedom allow a more ‘ordered’ glassy
material to evolve. If the length of the organic segment becomes very long
in comparison to the size of the cube, a disordered polymer-like network is
obtained.
Time-resolved in-situ X-ray diffraction study of the formation
of 3D-hexagonal mesoporous silica films
Authors: Grosso D. , Albouy P.A. , Amenitsch H. , Balkenende A.R. , Babonneau F.
Published: May 2019

Highly oriented 3D-hexagonal silica thin films have been produced on silicon
substrates by dip-coating technique, using cetyltrimethylammonium (CTAB)
bromide as structuring agent. For the first time, time-resolved in situ
X-ray diffraction experiments have been used to investigate the formation of
such mesostructured films. Interestingly, the data shows that an
intermediate mesophase appears just after film deposition (t<500 ms),
characterized by one diffraction peak centered at a d spacing of 65 Å. Then
after 20 s, another mesophase appears with a shorter d spacing (44 Å), which
corresponds to the 3D-hexagonal structure found for the final dried
film.
Size Control of Block Polymer Templated Mesoporous Silicate
Materials
Authors: Yamada Takeo , Asai Keisuke , Ishigure Kenkichi , Endo Akira , Zhou Hao S. , Honma Itaru
Published: May 2019

Mesoporous materials have attracted considerable interest because of
applications in molecular sieve, catalyst, and adsorbent. It will be useful
for new functional device if functional molecules can be incorporated into
the pore of mesoporous material. However, it is necessary to synthesize new
mesoporous materials with controlled large pore size. Recently, new class of
mesoporous materials has been prepared using triblock copolymer as a
template. In this paper, we reported that hexagonal and cubic structure
silicate mesoporous materials can be synthesized through triblock copolymer
templating, and their size was controlled by synthesis condition at
condensation.
The Synthesis of Hybrid Materials by the Blending of Polyhedral
Oligosilsesquioxanes into Organic Polymers
Authors: Blansky Rusty L. , Phillips Shawn H. , Chaffee Kevin , Lichtenhan Joseph , Lee Andre , Ping Geng Hei
Published: May 2019

The study of organic/inorganic hybrid materials has become an increasingly
widespread research focus. The advantage derived from such materials is the
combining of two very different compounds which may result in something that
bridges the performance gap between the two systems. We have previously
reported such hybrid systems prepared by incorporating polyhedral
oligosilsesquioxanes (POSS™) into traditional organic polymers by the
copolymerization of POSS™ monomers and organic monomers. This presentation
will discuss a more convenient method of incorporating POSS™ into a polymer:
the blending of POSS™ into organic polymers. The research discussion will
focus on the development of the POSS™ macromers used in our studies as well
as the POSS™ polymer blends synthesized. One important property enhancement
observed is the increase in surface hardness for a POSS™/poly styrene
sample.
Hybrid composite materials containing magnetic iron oxide
nanoparticles
Authors: Chanéac Corinne , Tronc Elisabeth , Jolivet Jean-Pierre
Published: May 2019

Hybrid magnetic composites made up of calibrated maghemite nanoparticles
well dispersed in an epoxide resin were obtained by polymerization of the
resin inside stable organosols of maghemite. The sol stability was ensured
by ligand adsorption onto the particle surface. Studies of phenylphosphonic
acid adsorption are presented. They show a strong interaction between PPA
ions and hydroxyl groups of particle surface and through bridging
≡Fe2O2POΦ species. Infrared and Mössbauer
spectroscopies as well as quasi- elastic light scattering and transmission
electron microscopy were used to characterize the materials.
Solventless Sol-Gel Chemistry Through Ring-Opening
Polymerization of Bridged Disilaoxacyclopentanes
Authors: Rahimian Kamyar , Loy Douglas A.
Published: May 2019

Ring-opening polymerization (ROP) of disilaoxacyclopentanes has proven to be
an excellent approach to sol-gel type hybrid orgainc-inorganic materials
[1]. These materials have shown promise as precursors for encapsulation and
microelectronics applications (Figure 1). The polymers are highly
crosslinked and are structurally similar to traditional sol-gels, but unlike
typical sol-gels they are prepared by an organic base or Bronsted acid
(formic or triflic acid), without the use of solvents and water, they have
low VOC's and show little shrinkage during processing.
Synthesis of Mesoporous Titanium Phosphate
Authors: Barbé C.J. , Mitchell D.R.G. , Drabarek E. , Bartlett J.R , Woolfrey J.L. , Luca V.
Published: May 2019

Mesoporous titanium phosphates were synthesised using three different
approaches, involving reactions of titanium isopropoxide with long-chain
alkyl phosphates, and subsequent aging at 80°C for several days. The
resulting powders were characterised using XRD, TEM and N2
sorption.

The first approach involved the classical MCM methodology, where the
modified titanium precursor was added to an alkylphosphate micellar
solution. The resulting solids possess an organised, lamellar mesostructure.
However, removal of the surfactant, either by heating or leaching in strong
basic solution, leads to the collapse of the lamellar mesostructure.

In the second route, titanium alkoxide was pre-reacted with the long-chain
alkyl phosphate, then hydrolysed with a large excess of water prior to
ageing. Although the structure of the as-precipitated samples could be
easily tailored by changing the processing parameters such as the alkyl
phosphate chain length or phosphate/titanium ratio, surfactant removal by
heating invariably led to the production of microporous samples.

The third approach involved the hydrolysis of the acetylacetone-modified
titanium isopropoxide with excess water. The alkyl phosphate was then
introduced into the resulting suspension. Subsequent ageing under acidic
conditions destabilised the particles, leading to aggregation and subsequent
gelation. In contrast to the previous approaches, the pyrolysed solid
contained a significant proportion of mesopores, a high porosity (40%) and a
surface area exceeding 300 m2.g-1.
Chemical Design of Nanostructured Luminescent
Materials
Authors: Gacoin Thierry , Huignard Arnaud , Counio Guillaume , Boilot Jean-Pierre
Published: May 2019

During the last 50 years, there has been a considerable amount of work for
the elaboration of efficient luminescent materials, most of them dealing
with the search for new chemical compositions. Only a very few studies have
concerned the study of the influence of the microstructure of the materials
on their properties of emission, especially when the grain sizes of the
materials are in the nanometer range. On another side, important advances
have been performed in colloid chemistry in the last years, especially in
the case of II-VI chalcogenides, as a consequence on the intense activity
around the physics of quantum confinement in semiconductors.

The basic idea of this work is to show that the techniques developed in the
case of II-VI nanoparticles could find interesting applications for the
elaboration of nanostructured luminescent materials. This is first
illustrated in the case of pure CdS nanoparticles, whose properties are
deeply affected by their surface state and their chemical environment.
Incorporation of manganese in solid solution in the CdS particles
drastically changes the emission process, which now essentially depends on
the manganese content inside each particle. Finally, the extension of the
synthesis process to rare earth doped oxide particles is presented, and the
luminescence efficiency is discussed as a function of the size, the
structure, and the chemical environment of the particles.
PHÂN TÍCH CÁC CHỈ SỐ NƯỚC TỪ ẢNH VỆ TINH LANDSAT 8 OLI ĐỂ CHIẾT TÁCH ĐƯỜNG BỜ BIỂN KHU VỰC TÂY NAM VIỆT NAM
Authors: Tuan Tran Anh , Nam Le Dinh , Nguyet Nguyen Thi Anh , Hong Pham Viet , Ngan Nguyen Thi Ai , Phuong Vu Le
Published: May 2019

The paper presents results of analysis of water indices using remote sensing data to extract an instantaneous shoreline at the time of image acquisition on the southwest coast of Vietnam. The water indices as NDWI (Normalized Difference Water Index), MNDWI (Modified Normalized Difference Water Index), and AWEI (Automated Water Extraction Index) were calculated from Landsat 8 OLI imagery. Then, an extracted distribution histogram of water indices’ values in the study area was used to separate the land from the sea. The position having abnormal frequency of pixels on the histogram is the threshold value to determine the boundary of land and water, and it is considered the shoreline. The study showed the threshold values of NDWI, MNDWI and AWEI which were defined at 0.12, 0.17 and 0.18 respectively. The precision of shoreline extraction from each respective water index was verified by field survey data using Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) methods. The verified results showed that MAE and MSE of the shorelines extracted from all three water indices were lower than an allowed limit of 30 m (equivalent to spatial resolution of the Landsat 8 image). However, the shoreline extracted from AWEI had the highest accuracy and it was considered the most appropriate shoreline at the acquisition time of image.
TIDAL ASYMMETRY IN MANGROVE FOREST - CASE STUDY IN SOUTHERN VIETNAM
Authors: Dung Tran Xuan , Phuoc Vo Luong Hong
Published: May 2019

The study aims to analyse the tidal asymmetry in mangrove forest by using the numerical modelling and the measured data in two mangrove forest areas: Can Gio (Ho Chi Minh city) and Cu Lao Dung (Soc Trang province). The results of 2D model in the mangrove forest show that there is the asymmetry in current velocity: Two velocity peaks exist at flood tide and two at ebb tide. The current velocity is the sum of the tidal flows from the channel and from the tidal exchange between the creek and the swamp. The calculated velocity depends strongly on drag force, which is due to the mangrove vegetation. Furthermore, the results from analysing the measured data in February 2012 in Can Gio, Ho Chi Minh city and in Sept–October 2014 in Cu Lao Dung (Soc Trang) also prove the existence of the tidal asymmetry: The current velocity in the mangrove at flood tide is more dominant than velocity at ebb tide. The water level also has the asymmetry, changes in the tidal cycles but does not get so dominant as the velocity does.
XÁC ĐỊNH HỆ SỐ TÍCH TỤ HÓA CHẤT BẢO VỆ THỰC VẬT CƠ CLO (OCPs) TRONG MỘT SỐ LOÀI NHUYỄN THỂ HAI MẢNH VỎ Ở KHU VỰC CỬA SÔNG SOÀI RẠP - TpHCM
Authors: Tong Nguyen Xuan , Huong Tran Thi Thu , Huong Mai , Thuy Duong Thi
Published: May 2019

Deposited sediments contain organochlorine pesticide chemicals which can pollute surface water as well as aquatic ecosystems. In this study, the accumulation of organochlorine pesticide chemicals in the bivalve mollusk group including Pacific oyster (Crassostrea gigas, Thunberg, 1793), green mussel (Perna viridis), blood scallop (Anadara granosa) ), white clam (Meretrix lyrata) and pearl oyster (Pinctada maxima) at Soai Rap estuary, Ho Chi Minh city was selected as subject of this research because of their high bioaccumulation capacity; their sedentary life, organic residue filter feeding habit and the ability to clean the lagoon environment. The pesticide chemicals were analyzed on GC-ECD system. Result of this research shows the different levels of accumulation in meat tissues of 5 species but they are lower than the allowable value of MARD 193:2004 - The bivalve mollusk harvest zone - Conditions to ensure food hygiene and safety. The results of calculating the Bio-Accumulation Factor (BAF) and Biota Sediment Accumulation Factor (BSAF) of the five species have shown that the bioaccumulation of organochlorine pesticides (OCPs) of bivalve mollusks in the area is natural tendency. BAF and BSAF of Crassostrea gigas were 56.672 and 0.429, Perna viridis were 66.730 and 0.608, Anadara granosa were 123.884 and 1.974, Meretrix lyrata were 52.060 and 0.489, Pinctada maxima were 115.176 and 1.076, respectively.
ANTIMICROBIAL, CYTOTOXIC AND HEMOLYTIC ACTIVITIES OF MARINE ALGAE-ASSOCIATED FUNGAL ISOLATES IN VIETNAM
Authors: Chi Hoang Kim , Ha Tran Thi Hong , Cuong Le Huu , Hang Tran Thi Nhu , Tuan Nguyen Dinh , Nhung Le Thi Hong , Huong Le Mai
Published: May 2019

In the context of sources for natural products discovery are going scarcer, exploiting biotechnologically potential compounds from marine microbial symbionts is considered a relatively new trend. In our study a total of fifteen fungal strains were isolated from marine algal samples belonging to species Kappaphycus cottonii, K. striatus, Gracilaria eucheumatoides and Betaphycus gelatinus collected in Nha Trang in 2017. The in vitro biological activities, including antimicrobial, cytotoxic and hemolytic activities of ethyl acetate extracts of the fungal strains were determined. From fifteen fungal extracts, six displayed antimicrobial activity against at least one test strain. At 20 μg.ml-1, four fungal extracts were found to express cytotoxic activity on two human cancer cell lines hepatocellular carcinoma (Hep-G2) and breast adenocarcinoma (MCF-7), with G. eucheumatoides being the source of the highest number of producer strains. Hemolytic activity was observed in rabbit erythrocytes under almost all fungal extracts’ effect. No apparent relationship was observed between the biological activities of fungal isolates. The biological assessments uncovered several fungal candidates, such as Bge-1.1, Kco-2.1 and Geu-1.1 with relatively potent antimicrobial and cytotoxic activities while expressing less hemolytic effect at concentrations from 20 μg.ml-1 to 200 μg.ml-1. The results evidenced the potential of exploiting natural products from associated marine microorganisms, especially those for the purpose of pharmaceutical applications.
DNA BARCODING APPLICATION OF MITOCHONDRIAL COI GENE TO IDENTIFY SOME FISH SPECIES OF FAMILY GOBIIDAE IN VIETNAM
Authors: Binh Phung Thi Xuan , Da Le Nhu , Quynh Le Thi Phuong , Ha Hoang Thi Thu , Thuy Duong Thi , Hanh Le Thi My
Published: May 2019

The Red river system is a typical example of Southeast Asian rivers that is strongly impacted by human and climatic conditions, especially in the recent period. In this paper, we aim to investigate the longitudinal variation of the water quality of the Red river, in the section from Hanoi city to the Ba Lat estuary. The sampling campaigns were conducted in the dry seasons in 2017 and 2018. The monitoring results showed that the average concentrations of nutrients (NO2-, NO3-, NH4+, PO43-) were still lower than the allowed values of the Vietnamese standard limits for surface water quality (QCVN 08:2015/BTNMT, column A1) whereas the average concentrations of Cl- and TSS exceeded the allowed values of the QCVN 08:2015/BTNMT, column A1 4.6 and 2.3 times, respectively. NO3- and dissolved silica (DSi) concentrations showed a significant variation from the Hanoi site to the Ba Lat site (6.62 mg/l to 1.19 mg/l for NO3- and 5.21 mg/l to 2.14 mg/l for DSi) whereas SO42-, NO2- and Cl- increased markedly in this longitudinal section, especially from the point SH6 where the salinity started to increase. Based on the three different methods for classification of trophic levels and on the different variables observed during the dry seasons in 2017–2018, the nutrient concentrations of the Red river water tended to slightly increase from the site Hanoi (SH1) to the site SH5 at Nam Dinh, indicating the increase of nutrient external input along the river whereas it tended to decrease from the site SH6 (at mesotrophic/eutrophic level) to the last observed site SH9 (at oligotrophic/mesotrophic level) at the sea due to the dilution of seawater. Seawater in dry season could affect directly the river downstream about 35 km far from the sea. The results may be a guide for planning of water use including agricultural irrigation in the Red river estuary.
Video-Assisted Self-Assessment of Basic Life Support skills in Medical Students
Authors: Ramakrishnan Ramya , Trichur Venkatakrishnan Ramakrishnan , Vijayan Parthasarathy , Cattamanchi Srihari
Published: May 2019

This article was migrated. The article was not marked as recommended. AimThis study seeks to evaluate the utility of video-assisted self-assessment in the attainment of basic life support (BLS) skills in medical students.MethodsOn procuring approval from the Institutional Ethics committee, third-year medical students were enrolled in the study. A large group interactive session on BLS skills was conducted followed by a demonstration of BLS skills on a manikin by the instructor. The students' performance was recorded using an Apple iPad. Self-assessment was done by the students twice using a standard checklist - before and after watching the video recordings of their performance. The disparity in the self-assessment scores before and after watching their video was analyzed, which was compared with that of the instructors' feedback, using students 't' test and Mann Whitney test. Feedback about this assessment methodology was obtained using a questionnaire.ResultsForty-one 3rd year medical students participated. A significant difference (<0.05) in the students pre and post video assessment scores was observed. All students agreed that watching the video recording of their skill performance helped them identify the errors better.ConclusionsIn conclusion, video-assisted assessment is an effective and a feasible method to improve self-assessment accuracy regarding clinical skills.