bluuebunny/crossref_metadata_2025 huggingface dataset:
Interactive teaching materials based on scientific approach: triangles and quadrilaterals
Authors: Pujiastuti Heni
Published: January 2018

One of the Indonesian government’s efforts to improve the quality of education is by changing the curriculum. Currently the Curriculum 2013 is being implemented in schools. Implementation of Curriculum 2013 is require teaching materials in accordance with the characteristics of the students, utilizing computer technology facilities, and contains the components of the scientific approach. Therefore, it is necessary to develop teaching materials in accordance with the Curriculum 2013. In this research we developed the Interactive Teaching Materials based on Scientific Approach (ITMSA). The research method is research and development (R&D) which consist of ten steps. The product design validation performed by multimedia, mathematics, and mathematics education expert involving lecturers and mathematics teacher. Utility testing of product conducted on junior high school students in Serang City, Banten Province, Indonesia. Based on research known that the ITMSA obtained a total score 85,30% from mathematics expert, 87,80% from mathematics education expert, 83,60% from multimedia expert, and 89,40% from students. In addition, students mathematical concept understanding who learn by using ITMSA better than student who learn without ITMSA. From these results concluded that the ITMSA is considered feasible and can be used in mathematics teaching in schools.
Teaching Practice in Distance Education Context
Authors: Fatmasari Rhini , Suripto
Published: January 2018

Teaching practice is an activity designed to enable students in mastering teaching skills. This activity is very important to improve the ability of prospective teachers, because theoretical knowledge has not been able to equip the teaching practice. The practice of teaching at schools provides a real experience for students in the real class, because theoretical knowledge through the process of learning in the classroom can not equip the teaching practice.

Faculty of Teacher Training and Education of Indonesia Open University (UT) with distance learning system has designed Teaching Practice through Praktek Kemampuan Mengajar (PKM) course with 3 credit score. PKM is implemented in the schools where they teach and are guided by two supervisors. The PKM exam is conducted at the designated centre schools at each UT Regional Office .

This study is aimed to evaluate the activities of PKM students of Economic Education Studies Program FKIP UT in UT Regional Office. The study was conducted at 12 UT Regional Office samples involving respondents consisting of UT students and UT Regional Office staff.

The results showed the level of independence of students doing PKM was quite high (72%). This level of independence needs to be supported by a 43% improvement in preparation and administrative services at UT Regional Office. In the implementation of teaching practice in schools, in average 53.14% Supervisor 1 and 63.86% Supervisor 2 always provide direction in accordance with UT standards. While 62.5% of Headmaster Sentra has role in accordance with its function.
The implementation of student team achievement division and picture series on improving the speaking skill of the 3rd grade students of cipta dharma elementary school in academic year 2016/2017
Authors: Handayani Nengah Dwi , Gana Kumara Dewa Gd. Ag.
Published: January 2018

The aim of this research was to find out whether or not the Speaking Skill of the 3rdgrade students of Cipta Dharma Elementary School could be improved through Student Team Achievement Division (STAD) and Picture Series in Academic Year 2016/2017. This Research used a Classroom Action Research with the total 36 students taken as subject. The result was, in Pre Cycle 52.78% (19 students); in Cycle 1 69.44% (25 students); and in Cycle 2 88.89% (32 students) reached the minimum completeness learning mastery. Based on the result, it could be concluded that the subject’s Speaking Skill could be improved the implementation of STAD and Picture Series.
The Skill in Designing Explorative Learning Tools Of Mathematics Pre-Service Teachers Through Explorative Learning Based On Metacognitive Scaffolding
Authors: Nindiasari Hepsi , ViviYandari IndhiraAsih , Khaerunnisa Etika , Pamungkas Aan Subhan
Published: January 2018

This study is back grounded by the fact that according to the result of TIMSS survey, Indonesian students’ achievement in mathematics is still low. This study aims to see mathematics pre-service teachers’ skill in developing learning tools after given explorative learning based on scaffolding metacognitive. The method of study use experimental quasi which is given to one group or class. The population of this study are mathematics pre-service teachers in University of Sultan AgengTirtayasa, Banten Province. The subject of sample taken is one class which is given initial treatment with explorative learning, then students performance in designing learning tools is assessed. Next, they are given explorative learning based on scaffolding metacognitive, and then their performance in designing learning tools is assessed. The instrument used is performance portfolio which is supported by a rubric to assess skill in designing explorative learning tools. The result shows that students in designing learning tools in the form of scenario based on Worksheet and in designing Worksheet after receiving explorative learning based on scaffolding metacognitive (very good category, mean score are 94.20 and 91.27) are better than before (explorative activity without scaffolding metacognitive) with very good category with the mean score are 85.27 and 86.11).
Literation Movement From Tanah Ombak’s Community
Authors: Putra EkaVidya
Published: January 2018

Nowadays, Character education becomes the attention of many parties. The key to character education is the availability of a positive character environment. Because character building is not enough just to provide knowledge about which is good attitude and what is bad as taught in school. This misunderstanding of school is the cause of character education and failure. Intended for character building requires a character environment that provides good examples to its members. The problem is that there are many character environments that do not support the building of good characters. Bad character environments can be seen in slum area. Slums, identical to poverty, low levels of education, many criminal acts, promiscuity and other negative behaviors. By using a new institutional approach . Data collection is done by qualitative method, through observation, interview and literature study. The success of the Tanah Ombak Community manipulates the institutional environment can not be separated from two things. First, there are actor who become key figures. Second, there in collectively shared values that drives ideas. How the environment is manipulated can be seen from the three aspects, regulative, normative and cognitive. Regulatively, many emergence of positive rules for character development. Normatively, bad old habits are replaced by positive new habits for character building. Finally, cognitively new knowledge emerges for the new characters building.
Character Education Based On Local Wisdom For the Prisoners
Authors: Muh Sukemi Buchory , Purwaningsih Okti , Handoko Sigit
Published: January 2018

This research aims at revealing the existence of character education based on the local wisdom for the prisoners. The subject of this research is the prisoner inhabitant in Wirogunan Prison and Narcotics pakem in Sleman Yogyakarta. The data were gained by interviewing, documenting and demonstrating. The data were analyzed qualitative and quantitative descriptively. The results of this research are: (1) The training of Tembang Maca Pat and Javanese MC are equivalently adapted, (2) The character values being shaped: believe in God, responsibility, respect, fairness, confidence, faithfulness, discipline, careness, spirituality, manners, intelligence, emotion control, character building, the increase of social participants; (3) The competence on Tembang Maca Pat and MC of Javanese can be used as professional earning in society and also can be used as educational model for the prisoners.
Application Of Treatment Trait Interaction To Improve Learning Of Chemistry
Authors: Aswirna Prima
Published: January 2018

This research leave from the fact that performance study of Majors student of Tadris Natural Sciences Concentration Physics (IPA-FISIKA) State Islamic University Imam Bonjol. The aims of this research were: (1) Searching ability correlation between content of capability in Chemistry and religiosity. (2) Differentiating study performance by using model of Trait Treatment Interaction (TTI) between class with capable student group early is high (learner fastern) and class with student group ably early lowering (slower learner) by using method study of autodidact (learning self) and learn habit (teaching regular) added with tutorial. This research use method of quasy experiment. Technique data collecting through test and observation, Total of population counted 101 people. But, only 66 students as a sample. The research conclude : (1) The self-learning was suitable to teach for students with high capability of knowledge (faster lesrner). (2) The regular teaching + tutorial was suitable to teach for students with lower capability of knowledge (slower learner). (3) There were correlation between religiosity and capability of content (chemistry of knowledge). (4) Trait treatment interaction can be improve the capability of academic performance of students Chemistry Science.
The Complexity integrated-Instruments components media of IPA at Elementary School
Authors: Angreni Siska , Sari Rona Taula
Published: January 2018

This research aims at describing the complexity of Integrated Instrument Components media (CII) in learning of science at Elementary schools in District Siulak Mukai and at Elementary schools in District Siulak. The research applied a descriptive method which included survey forms. Instruments used were observation sheets. The result of the research showed Integrated Instrument Components media (CII) natural science that complexity at primary school district Siulak was more complex compared with that at primary school district Siulak Mukai. is better than from primary school district Mukai
Construction of Functionalized (Dihydro)thieno[2,3-c]chromene Derivatives via a Domino Michael Addition/Intramolecular
Cyclization Reaction
Authors: Xie Jian-Wu , Yu Li-Si-Han , Dong Jian-Lian , Gao Zhi-Jian , Wang Jing
Published: January 2018

A one-pot synthesis of substituted (dihydro)thieno[2,3-c]chromene derivatives was developed through a Lewis base catalyzed domino Michael addition/intramolecular cyclization reaction between 3-nitro-2H-chromenes and thioamides. The desired (dihydro)thieno[2,3-c]chromene derivatives were prepared with a large substrate scope (22 examples) and excellent diastereoselectivity in moderate to excellent yields.
Efficient Synthesis of 1-Thiomansonones with Anti-MRSA Activity
Authors: Shin Dongyun , Park Seong-Hyuk , Park Sooyoung , Lee Chang-Yong , Suh Young-Ger
Published: January 2018

In this study, we developed an efficient and general synthetic strategy for thiaphenalene, a sulfur-containing polyaromatic hetero­cycle, and applied for the synthesis of 1-thio derivatives of mansonone I and F, natural 1-oxaphenalenic orthoquinones. The pivotal steps for the construction of thiophenalene skeleton include formation of arylsulfide by Newman–Kwart rearrangement of thiocarbamate or palladium-­catalyzed cross-coupling, and pericyclic ring closure. Three bioisosterically modified orthoquinones were synthesized and were evaluated for anti-MRSA activity.
Anaphylaxis Following Human Prothrombin Complex Concentrate in a Child with Lupus Anticoagulant Hypoprothrombinemia Syndrome: A Cautionary Tale
Authors: Mediwake Heshani , Robertson Jeremy , Beggs Joanne , Mason Jane
Published: January 2018

A previously healthy 3-year-old girl presented with a short history of mucocutaneous bleeding and a spontaneous left knee hemarthrosis following a nonspecific viral gastroenteritis. Initial investigations for a bleeding disorder revealed a normal platelet count; however, coagulation studies revealed a prothrombin time (PT) of 25 seconds and an activated partial thromboplastin time (APTT) of 66 seconds (both prolonged). The APTT did not correct on mixing with normal plasma, and further testing confirmed the presence of a strong lupus anticoagulant (LA). One-stage assays of factor VIII, VII, and X were normal, but factor II was markedly reduced. Based on this distinct clinicopathological picture, a diagnosis of lupus anticoagulant hypoprothrombinemia syndrome (LAHS) was made. Due to the presence of a hemarthrosis, the patient was treated with clotting factor concentrate. Human prothrombin complex concentrate (PROTHROMBINEX-VF) was used as a source of factor II replacement; however, during the infusion the patient developed anaphylaxis necessitating resuscitation. The patient was observed without further factor replacement, and the bleeding symptoms resolved over several days. Within 3 weeks her PT and factor II had normalized but the APTT remained prolonged. After 6 months the coagulation profile had completely normalized and the LA was negative. It is unusual to require replacement of factor II in paediatric LAHS because bleeding is typically minor and self-limited. Anaphylaxis to clotting factor concentrates has not been previously reported in the context of LAHS, but is well described in patients with congenital factor IX deficiency (hemophilia B). Whilst the potential mechanism for anaphylaxis in our patient is unknown, it is recommended that human prothrombin complex concentrates should be used cautiously in paediatric LAHS.
The Variation of Disulfides in the Progression of Type 2 Diabetes Mellitus
Authors: Ergin Merve , Aydin Cevdet , Yurt Emine Feyza , Cakir Bekir , Erel Ozcan
Published: January 2018

Aim The purpose of this study was to examine thiol-disulfide balance in patients with type 2 diabetes mellitus.

Methods This study included 32 subjects with known type 2 diabetes mellitus without complications, 30 patients with type 2 diabetes mellitus with complications, 28 newly diagnosed patients with type 2 diabetes mellitus, and 45 healthy individuals. Thiol-disulfide profile tests were quantified in all groups.

Results Compared to the control group, patients in each of the diabetic groups had significantly lower native and total thiol levels, higher disulfide levels, and higher disulfide/native thiol and disulfide/total thiol ratios (p<0.05 for all). Disulfide levels were significantly lower in the newly diagnosed group than in other diabetic groups (p<0.05). There were significant associations between glycemic parameters and thiol-disulfide tests (p<0.05).

Conclusions A disequilibrium between thiol-disulfide pairs occurs in patients with type 2 diabetes mellitus, and a gradual increase to disulfide levels may contribute to the disease’s severity. Deteriorated thiol-disulfide homeostasis may be relevant to the pathophysiology of type 2 diabetes mellitus.
Evaluation of beam divergence of a negative hydrogen ion beam using Doppler shift spectroscopy diagnostics
Authors: Deka A. J. , Bharathi P. , Pandya K. , Bandyopadhyay M. , Bhuyan M. , Yadav R. K. , Tyagi H. , Gahlaut A. , Chakraborty A.
Published: January 2018

The Doppler Shift Spectroscopy (DSS) diagnostic is in the conceptual stage to estimate beam divergence, stripping losses, and beam uniformity of the 100 keV hydrogen Diagnostics Neutral Beam of International Thermonuclear Experimental Reactor. This DSS diagnostic is used to measure the above-mentioned parameters with an error of less than 10%. To aid the design calculations and to establish a methodology for estimation of the beam divergence, DSS measurements were carried out on the existing prototype ion source RF Operated Beam Source in India for Negative ion Research. Emissions of the fast-excited neutrals that are generated from the extracted negative ions were collected in the target tank, and the line broadening of these emissions were used for estimating beam divergence. The observed broadening is a convolution of broadenings due to beam divergence, collection optics, voltage ripple, beam focusing, and instrumental broadening. Hence, for estimating the beam divergence from the observed line broadening, a systematic line profile analysis was performed. To minimize the error in the divergence measurements, a study on error propagation in the beam divergence measurements was carried out and the error was estimated. The measurements of beam divergence were done at a constant RF power of 50 kW and a source pressure of 0.6 Pa by varying the extraction voltage from 4 kV to10 kV and the acceleration voltage from 10 kV to 15 kV. These measurements were then compared with the calorimetric divergence, and the results seemed to agree within 10%. A minimum beam divergence of ∼3° was obtained when the source was operated at an extraction voltage of ∼5 kV and at a ∼10 kV acceleration voltage, i.e., at a total applied voltage of 15 kV. This is in agreement with the values reported in experiments carried out on similar sources elsewhere.
Response of a core coherent density oscillation on electron cyclotron resonance heating in Heliotron J plasma
Authors: Kobayashi T. , Kobayashi S. , Lu X. X. , Kenmochi N. , Ida K. , Ohshima S. , Yamamoto S. , Kado S. , Kokubu D. , Nagasaki K. , Okada H. , Minami T. , Otani Y. , Mizuuchi T.
Published: January 2018

We report properties of a coherent density oscillation observed in the core region and its response to electron cyclotron resonance heating (ECH) in Heliotron J plasma. The measurement was performed using a multi-channel beam emission spectroscopy system. The density oscillation is observed in a radial region between the core and the half radius. The poloidal mode number is found to be 1 (or 2). By modulating the ECH power with 100 Hz, repetition of formation and deformation of a strong electron temperature gradient, which is likely ascribed to be an electron internal transport barrier, is realized. Amplitude and rotation frequency of the coherent density oscillation sitting at the strong electron temperature gradient location are modulated by the ECH, while the poloidal mode structure remains almost unchanged. The change in the rotation velocity in the laboratory frame is derived. Assuming that the change of the rotation velocity is given by the background E × B velocity, a possible time evolution of the radial electric field was deduced.
Capillary evaporation of the ionic liquid [EMIM][BF4] in nanoscale solvophobic confinement
Authors: Shrivastav Gourav , Remsing Richard C. , Kashyap Hemant K.
Published: January 2018

Solvent density fluctuations play a crucial role in liquid-vapor transitions in solvophobic confinement and can also be important for understanding solvation of polar and apolar solutes. In the case of ionic liquids (ILs), density fluctuations can be used to understand important processes in the context of nanoscale aggregation and colloidal self-assemblies. In this article, we explore the nature of density fluctuations associated with capillary evaporation of the IL 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]) in the confined region of model solvophobic nanoscale sheets by using molecular dynamics simulations combined with non-Boltzmann sampling techniques. We demonstrate that density fluctuations of the confined IL play an important role in capillary evaporation, suggesting analogies to dewetting transitions involving water. Significant changes in the interfacial structure of the IL are also detailed and suggested to underlie a non-classical (non-parabolic) dependence of the free energy barrier to evaporation on the degree of confinement.
High-field magnetoelasticity of Tm2Co17 and comparison with Er2Co17
Authors: Andreev A. V. , Zvyagin A. A. , Skourski Y. , Yasin S. , Zherlitsyn S.
Published: January 2018

Acoustic properties (ultrasound velocity and attenuation) and magnetostriction were measured in pulsed fields up to 60 T applied along the c axis of Tm2Co17 single crystal. Similar to Er2Co17, the transition in Tm2Co17 is accompanied by clear anomalies in the sound velocity. The observed 0.3% jump of the sound velocity at the transition is negative in Tm2Co17, whereas it is positive in Er2Co17. The magnetostriction at the transition also differs very much from that in Er2Co17. In Tm2Co17, the transition is accompanied by a smooth minimum of 0.15 × 10−4 in longitudinal magnetostriction whereas in Er2Co17 by a very sharp expansion of much larger magnitude (1.2 × 10−4). In the transverse mode, the effect in Tm2Co17 looks as very broad minimum of low amplitude (<0.1 × 10−4) whereas in Er2Co17 as very sharp and large shrinkage (2.6 × 10−4). Thus, both the magnetoacoustics and magnetostriction are rather different in Tm2Co17 and Er2Co17. This supports different nature of the field-induced transitions in these compounds.
Hysteresis of magnetization reversal loops in films with perpendicular anisotropy in an inclined magnetic field
Authors: Ryabchenko S. M. , Kalita V. M.
Published: January 2018

Numerical calculations of magnetization reversal loops of nanogranular films having perpendicular anisotropy in an inclined magnetic field at finite temperature, for film “quality parameters” both less than, and greater than, one. The calculations are performed with consideration of the film's demagnetizing field in the two-level approximation for the energy of the granule. It is found that the hysteresis of the transition fields between states with uniformly directed and non-uniformly directed magnetic moments for all granules narrows with increasing temperature and field deviation angle from the normal to the film. As the field deviation increases this hysteresis vanishes, and there is a transition from the uniformly magnetized state of the granules to the equilibrium non-homogeneous state without hysteresis. In the case of large field deflection angles, at finite temperature the magnetization consists of three regions. At the center of the magnetization curve there is a hysteresis region in which the magnetic moments of the particles have different directions. As the absolute value of the field increases, it transitions to a region of equilibrium nonhysteretic magnetization with different directions of the particles' magnetic moments. And then, this hysteresis-free region transitions to a state having uniformly directed magnetic moments for all particles.
Optical characteristics of the nanoparticle coupled to a quantum molecular aggregate
Authors: Ropakova I. Yu. , Zvyagin A. A.
Published: January 2018

Optical characteristics of a single nanoparticle, coupled to the one-dimensional quantum molecular aggregate is studied. Depending on the values of the coupling of the particle and its own frequency, with respect to the own frequency of the aggregated molecules, and the strength of the aggregation, the dynamical relative permittivity of the nanoparticle manifests the contribution from the exciton band, or/and the ones from the local level(s) caused by the particle. The refractive index and the extinction coefficient of the nanoparticle is also calculated.
Magnetic and acoustic properties of CoCr2S4
Authors: Felea V. , Cong P. T. , Prodan L. , Gritsenko Y. , Wosnitza J. , Zherlitsyn S. , Tsurkan V.
Published: January 2018

We report results of magnetic and ultrasound studies of the sulfide spinel CoCr2S4, for which the multiferroicity has recently been suggested. Clear anomalies in the magnetic and acoustic properties have been observed at TN = 222 K and in applied magnetic fields evidencing the important role of magnetoelastic interactions in this material. In contrast, no anomalies have been detected at TC = 28 K, where a spontaneous electric polarization and isostructural distortions have been reported. We have extracted the H–T phase diagram of CoCr2S4 from our experiments for magnetic fields applied along the ⟨111⟩ direction. We discuss our observations in relation to our earlier results obtained for the oxide multiferroic spinel CoCr2O4.
Validity of t–J approximation for extended Hubbard model with strong repulsion
Authors: Cheranovskii V. O. , Klein D. J. , Ezerskaya E. V. , Tokarev V. V.
Published: January 2018

It is shown that for finite cyclic systems described by two band Hubbard Hamiltonian with strong electron repulsion the reduction to effective t–J model may give incorrect description of the ground state symmetry due to neglect of the correlated hopping terms.
Magnetic properties of the spin-1 chain compound NiCl3C6H5CH2CH2NH3
Authors: Lipps F. , Arkenbout A. H. , Polyakov A. , Günther M. , Salikhov T. , Vavilova E. , Klauss H.-H. , Büchner B. , Palstra T. M. , Kataev V.
Published: January 2018

We report experimental results of the static magnetization, ESR and NMR spectroscopic measurements of the Ni-hybrid compound NiCl3C6H5CH2CH2NH3. In this material NiCl3 octahedra are structurally arranged in chains along the crystallographic a axis. According to the static susceptibility and ESR data Ni2+ spins S = 1 are isotropic and are coupled antiferromagnetically (AFM) along the chain with the exchange constant J = 25.5 K. These are important prerequisites for the realization of the so-called Haldane spin-1 chain with the spin-singlet ground state and a quantum spin gap. However, experimental results evidence AFM order at TN ≈ 10 K presumably due to small interchain couplings. Interestingly, frequency-, magnetic field-, and temperature-dependent ESR measurements, as well as the NMR data, reveal signatures which could presumably indicate an inhomogeneous ground state of co-existent mesoscopically spatially separated AFM ordered and spin-singlet state regions similar to the situation observed before in some spin-diluted Haldane magnets.
(H,Ti)-diagram of magnetic transformations induced by a pulsed magnetic field in antiferromagnetic LiCoPO4
Authors: Khrustalyov V. M. , Savytsky V. N. , Kharchenko M. F.
Published: January 2018

A study of the differential magnetic susceptibility and electric polarization of an antiferromagnetic LiCoPO4 crystal in a pulsed magnetic field with an intensity of up to 290 kOe, directed along the antiferromagnetism vector of the spin-ordering main mode (Hǁb), at initial sample temperatures between 1.6 and 20.8 K. An adiabatic (H, Ti)-diagram of magnetic phase transitions is constructed. In addition to the three transitions that were discovered earlier at helium temperatures, higher temperatures revealed singularities that indicate the existence of a first-order phase transition line in the high-field phase II, which ends at a critical point. The coordinates of the critical point at which the lines of the phase transitions bordering the region of existence of high-field phase III converge with the line of the phase transitions from phase II to the saturated paramagnetic phase, are also determined.
Adsorption of hairy particles with mobile ligands: Molecular dynamics and density functional study
Authors: Borówko M. , Sokołowski S. , Staszewski T. , Pizio O.
Published: January 2018

We study models of hairy nanoparticles in contact with a hard wall. Each particle is built of a spherical core with a number of ligands attached to it and each ligand is composed of several spherical, tangentially jointed segments. The number of segments is the same for all ligands. Particular models differ by the numbers of ligands and of segments per ligand, but the total number of segments is constant. Moreover, our model assumes that the ligands are tethered to the core in such a manner that they can “slide” over the core surface. Using molecular dynamics simulations we investigate the differences in the structure of a system close to the wall. In order to characterize the distribution of the ligands around the core, we have calculated the end-to-end distances of the ligands and the lengths and orientation of the mass dipoles. Additionally, we also employed a density functional approach to obtain the density profiles. We have found that if the number of ligands is not too high, the proposed version of the theory is capable to predict the structure of the system with a reasonable accuracy.
Droplet spreading and capillary imbibition in a porous medium: A coupled IB-VOF method based numerical study
Authors: Das Saurish , Patel H. V. , Milacic E. , Deen N. G. , Kuipers J. A. M.
Published: January 2018

We investigate the dynamics of a liquid droplet in contact with a surface of a porous structure by means of the pore-scale level, fully resolved numerical simulations. The geometrical details of the solid porous matrix are resolved by a sharp interface immersed boundary method on a Cartesian computational grid, whereas the motion of the gas-liquid interface is tracked by a mass conservative volume of fluid method. The numerical simulations are performed considering a model porous structure that is approximated by a 3D cubical scaffold with cylindrical struts. The effect of the porosity and the equilibrium contact angle (between the gas-liquid interface and the solid struts) on the spreading behavior, liquid imbibition, and apparent contact angle (between the gas-liquid interface and the porous base) are studied. We also perform several simulations for droplet spreading on a flat surface as a reference case. Gas-liquid systems of the Laplace number, La = 45 and La = 144 × 103 are considered neglecting the effect of gravity. We report the time exponent (n) and pre-factor (C) of the power law describing the evolution of the spreading diameter (S = Ctn) for different equilibrium contact angles and porosity. Our simulations reveal that the apparent or macroscopic contact angle varies linearly with the equilibrium contact angle and increases with porosity. Not necessarily for all the wetting porous structures, a continuous capillary drainage occurs, and we find that the rate of the capillary drainage very much depends on the fluid inertia. At La = 144 × 103, numerically we capture the capillary wave induced pinch-off and daughter droplet ejection. We observe that on the porous structure the pinch-off is weak compared to that on a flat plate.
Structural analysis of zwitterionic liquids vs. homologous ionic liquids
Authors: Wu Boning , Kuroda Kosuke , Takahashi Kenji , Castner Edward W.
Published: January 2018

Zwitterionic liquids (Zw-ILs) have been developed that are homologous to monovalent ionic liquids (ILs) and show great promise for controlled dissolution of cellulosic biomass. Using both high energy X-ray scattering and atomistic molecular simulations, this article compares the bulk liquid structural properties for novel Zw-ILs with their homologous ILs. It is shown that the significant localization of the charges on Zw-ILs leads to charge ordering similar to that observed for conventional ionic liquids with monovalent anions and cations. A low-intensity first sharp diffraction peak in the liquid structure factor S(q) is observed for both the Zw-IL and the IL. This is unexpected since both the Zw-IL and IL have a 2-(2-methoxyethoxy)ethyl (diether) functional group on the cationic imidazolium ring and ether functional groups are known to suppress this peak. Detailed analyses show that this intermediate range order in the liquid structure arises for slightly different reasons in the Zw-IL vs. the IL. For the Zw-IL, the ether tails in the liquid are shown to aggregate into nanoscale domains.
Double layer of platinum electrodes: Non-monotonic surface charging phenomena and negative double layer capacitance
Authors: Huang Jun , Zhou Tao , Zhang Jianbo , Eikerling Michael
Published: January 2018

In this study, a refined double layer model of platinum electrodes accounting for chemisorbed oxygen species, oriented interfacial water molecules, and ion size effects in solution is presented. It results in a non-monotonic surface charging relation and a peculiar capacitance vs. potential curve with a maximum and possibly negative values in the potential regime of oxide-formation.
A simplified model for direct experimental determination of energy transfer quantum efficiency as a function of donor-acceptor interaction distance
Authors: Silva A. G. , Malachias A. , Cury L. A.
Published: January 2018

The exciton energy transfer in organic bilayer structures, consisting of donor and acceptor layers with volumetric and random dipole distribution, was investigated as a function of their separation distance. This complex system was analyzed using a simplified quantum efficiency model based on the integrating sphere method that enabled us to determine the dominant interaction mechanism, whose geometry for energy transfer considerably differs from a point-to-point dipole interaction. In addition, the proposed model can also be applied to retrieve the average interaction distance between donor and acceptor chromophores for systems with well known geometries.
Carrier diffusion as a measure of carrier/exciton transfer rate in InAs/InGaAsP/InP hybrid quantum dot–quantum well structures emitting at telecom spectral range
Authors: Rudno-Rudziński W. , Biegańska D. , Misiewicz J. , Lelarge F. , Rousseau B. , Sęk G.
Published: January 2018

We investigate the diffusion of photo-generated carriers (excitons) in hybrid two dimensional–zero dimensional tunnel injection structures, based on strongly elongated InAs quantum dots (called quantum dashes, QDashes) of various heights, designed for emission at around 1.5 μm, separated by a 3.5 nm wide barrier from an 8 nm wide In0.64Ga0.36As0.78P0.22 quantum well (QW). By measuring the spectrally filtered real space images of the photoluminescence patterns with high resolution, we probe the spatial extent of the emission from QDashes. Deconvolution with the exciting light spot shape allows us to extract the carrier/exciton diffusion lengths. For the non-resonant excitation case, the diffusion length depends strongly on excitation power, pointing at carrier interactions and phonons as its main driving mechanisms. For the case of excitation resonant with absorption in the adjacent QW, the diffusion length does not depend on excitation power for low excitation levels since the generated carriers do not have sufficient excess kinetic energy. It is also found that the diffusion length depends on the quantum-mechanical coupling strength between QW and QDashes, controlled by changing the dash size. It influences the energy difference between the QDash ground state of the system and the quantum well levels, which affects the tunneling rates. When that QW–QDash level separation decreases, the probability of capturing excitons generated in the QW by QDashes increases, which is reflected by the decreased diffusion length from approx. 5 down to 3 μm.
Perspective: Quantum Hamiltonians for optical interactions
Authors: Andrews David L. , Jones Garth A. , Salam A. , Woolley R. Guy
Published: January 2018

The multipolar Hamiltonian of quantum electrodynamics is extensively employed in chemical and optical physics to treat rigorously the interaction of electromagnetic fields with matter. It is also widely used to evaluate intermolecular interactions. The multipolar version of the Hamiltonian is commonly obtained by carrying out a unitary transformation of the Coulomb gauge Hamiltonian that goes by the name of Power-Zienau-Woolley (PZW). Not only does the formulation provide excellent agreement with experiment, and versatility in its predictive ability, but also superior physical insight. Recently, the foundations and validity of the PZW Hamiltonian have been questioned, raising a concern over issues of gauge transformation and invariance, and whether observable quantities obtained from unitarily equivalent Hamiltonians are identical. Here, an in-depth analysis of theoretical foundations clarifies the issues and enables misconceptions to be identified. Claims of non-physicality are refuted: the PZW transformation and ensuing Hamiltonian are shown to rest on solid physical principles and secure theoretical ground.
Spectral broadening and pulse compression of a 400 μJ, 20 W Yb:KGW laser using a multi-plate medium
Authors: Beetar John E. , Gholam-Mirzaei Shima , Chini Michael
Published: January 2018

We investigate the potential of a multi-plate medium consisting of thin fused silica plates to generate few-cycle pulses from a moderately high energy (400 μJ) and average power (20 W) Yb:KGW laser centered at 1025 nm. By optimizing the thicknesses and positions of the plates, we mitigate the losses associated with spatial and spectral distortions that can accompany self-focusing in bulk solids. Pulses with an initial duration of ∼280 fs were compressed using chirped mirrors, after spectral broadening in a multi-plate medium consisting of 6 mm of fused silica in total, by a factor of >5 to 50 fs. Further spectral broadening in a second stage also consisting of 6 mm of fused silica in total enabled compression to 18 fs with 40 μJ pulse energy, with the energy efficiency limited primarily by the geometry of the chirped mirror compressors.
Communication: Evaluating non-empirical double hybrid functionals for spin-state energetics in transition-metal complexes
Authors: Wilbraham Liam , Adamo Carlo , Ciofini Ilaria
Published: January 2018

The computationally assisted, accelerated design of inorganic functional materials often relies on the ability of a given electronic structure method to return the correct electronic ground state of the material in question. Outlining difficulties with current density functionals and wave function-based approaches, we highlight why double hybrid density functionals represent promising candidates for this purpose. In turn, we show that PBE0-DH (and PBE-QIDH) offers a significant improvement over its hybrid parent functional PBE0 [as well as B3LYP* and coupled cluster singles and doubles with perturbative triples (CCSD(T))] when computing spin-state splitting energies, using high-level diffusion Monte Carlo calculations as a reference. We refer to the opposing influence of Hartree-Fock (HF) exchange and MP2, which permits higher levels of HF exchange and a concomitant reduction in electronic density error, as the reason for the improved performance of double-hybrid functionals relative to hybrid functionals. Additionally, using 16 transition metal (Fe and Co) complexes, we show that low-spin states are stabilised by increasing contributions from MP2 within the double hybrid formulation. Furthermore, this stabilisation effect is more prominent for high field strength ligands than low field strength ligands.
High efficiency and broadband acoustic diodes
Authors: Fu Congyi , Wang Bohan , Zhao Tianfei , Chen C. Q.
Published: January 2018

Energy transmission efficiency and working bandwidth are the two major factors limiting the application of current acoustic diodes (ADs). This letter presents a design of high efficiency and broadband acoustic diodes composed of a nonlinear frequency converter and a linear wave filter. The converter consists of two masses connected by a bilinear spring with asymmetric tension and compression stiffness. The wave filter is a linear mass-spring lattice (sonic crystal). Both numerical simulation and experiment show that the energy transmission efficiency of the acoustic diode can be improved by as much as two orders of magnitude, reaching about 61%. Moreover, the primary working band width of the AD is about two times of the cut-off frequency of the sonic crystal filter. The cut-off frequency dependent working band of the AD implies that the developed AD can be scaled up or down from macro-scale to micro- and nano-scale.
Asymmetric adjustment of retail energy prices in Europe: Analysis of structural change and exchange rate dynamics
Authors: Ogbuabor Jonathan E. , Orji Anthony , Anthony-Orji Onyinye I.
Published: January 2018

This paper investigates the roles of structural changes and exchange rates in the relationship between retail energy prices and crude oil costs. Using a dummy variable approach, this paper argues that once the structural change in this relationship is taken into consideration, the empirical results of studies that found evidence in support of asymmetric behavior, which is largely obscured at pump where prices include both tax and duty, no longer hold. Adopting a nonlinear Auto Regressive Distributive Lag (ARDL) framework, this paper also shows that studies that failed to account for the exchange rate as part of the marginal cost of importing oil for countries with a high oil import dependency ratio may be misleading. Specifically, the results indicate that once the exchange rate effect is taken into consideration, the possibility of rent-seeking behavior in the gasoline markets of Italy and Spain disappears, while the rockets and feathers effect in the ex-tax gasoline, diesel, domestic heating oil, and industrial fuel oil markets of France, Germany, Italy, and Spain vanishes. Finally, employing instrumental variables and generalized method of moment estimators, this paper further finds that the results are robust and free from endogeneity issues.
Reductions of topologically massive gravity I: Hamiltonian analysis of second order degenerate Lagrangians
Authors: Çağatay Uçgun Filiz , Esen Oğul , Gümral Hasan
Published: January 2018

We present Skinner-Rusk and Hamiltonian formalisms of second order degenerate Clément and Sarıoğlu-Tekin Lagrangians. The Dirac-Bergmann constraint algorithm is employed to obtain Hamiltonian realizations of Lagrangian theories. The Gotay-Nester-Hinds algorithm is used to investigate Skinner-Rusk formalisms of these systems.
Cost-effective landscape revegetation and restoration of a grazing property on the Northern Tablelands of New South Wales: 65 years of change and adaptation at ‘Eastlake'
Authors: Williams Gordon Terrell
Published: January 2018

This paper describes the restoration of woody vegetation on my family’s grazing property, ‘Eastlake’ (1202 ha) on the Northern Tablelands of New South Wales. We commenced revegetating ‘Eastlake’ in 1981 to reverse the loss of native tree cover due to New England dieback and improve shelter for livestock and pastures to increase farm profitability. We treated the revegetation program as a long-term business investment and, apart from a 5-year period of overseas employment, have allocated annual funding in the farm business plan ever since. Our decision was based on the benefits of shelter to livestock and pasture production. Once we began revegetation, aesthetics, amenity and the positive impact on the capital value of the farm became important motivations. More recently, increasing the farm’s biodiversity and resilience, and conserving native flora and fauna, have also motivated us. Our strategy is to link upland areas of remnant timber with ridgeline corridors of planted vegetation to maximise shelter, minimise pasture production losses and provide dispersal corridors for fauna and wildlife habitat. Initially, we planted introduced species of tree and shrub, but now we revegetate mainly with native species, as well as fencing off remnant timber to encourage natural regeneration and direct seeding understorey species (mainly acacias) in degraded remnants and elsewhere. Our target is to increase the area of fenced-off and planted timber cover from 8% to 10% over the next few years, which will take the proportion of total effective timber cover from ~8% in 1980 to 18% of the property. The key lessons are to: (1) plan, prepare, plant the right tree or shrub in the right place for the right purpose, and post-planting care (the ‘4 Ps’); (2) integrate revegetation into the whole-farm business plan; (3) finance the work slowly over time with the aid of a spatial farm plan; and (4) adapt to changing circumstances, values and understanding. Research is required to help farmers understand the role of on-farm biodiversity in contributing to the health of the farm business, owner–managers and their families and the farm environment, as well as to regional economies, communities, landscapes and society more generally.
RNA force field with accuracy comparable to state-of-the-art protein force fields
Authors: Tan Dazhi , Piana Stefano , Dirks Robert M. , Shaw David E.
Published: January 2018

Significance

The complex and often highly dynamic 3D structures of RNA molecules are central to their diverse cellular functions. Molecular dynamics (MD) simulations have played a major role in characterizing the structure and dynamics of proteins, but the physical models (“force fields”) used for simulating nucleic acids are substantially less accurate overall than those used in protein simulations, creating a major challenge for MD studies of RNA. Here, we report an RNA force field capable of describing the structural and thermodynamic properties of RNA molecules with accuracy comparable to state-of-the-art protein force fields. This force field should facilitate the use of MD simulation as a tool for the study of biologically significant RNA molecules and protein–RNA complexes.
K63 ubiquitylation triggers proteasomal degradation by seeding branched ubiquitin chains
Authors: Ohtake Fumiaki , Tsuchiya Hikaru , Saeki Yasushi , Tanaka Keiji
Published: January 2018

Significance

Posttranslational modification of proteins by ubiquitylation regulates numerous biological processes. Polyubiquitin chain linkages are critical determinants that direct substrates to distinct pathways, a concept referred to as the ubiquitin code. Lysine-63 (K63)-linked polyubiquitin chains are the second most abundant linkage type in cells, and are known to regulate proteasome-independent pathways such as signal transduction and endocytosis. We report that K63-linked polyubiquitylation of the proapoptotic regulator TXNIP by the ubiquitin ligase ITCH triggers proteasome-mediated protein degradation. K63 ubiquitin chains facilitate subsequent assembly of K48/K63 branched ubiquitin chains through recruitment of ubiquitin ligases assembling K48 chains, thereby directing substrates to the proteasome. These results reveal an unappreciated ubiquitin-dependent pathway leading to the proteasome.
In vivo wireless photonic photodynamic therapy
Authors: Bansal Akshaya , Yang Fengyuan , Xi Tian , Zhang Yong , Ho John S.
Published: January 2018

Significance

The low penetration of light through tissue currently limits the therapeutic depth of photodynamic therapy (PDT) to less than a centimeter, even at near-infrared wavelengths. We report a wireless photonic approach to PDT in which miniaturized implantable devices deliver controlled doses of light by wireless powering through thick tissue. We demonstrate targeted cancer therapy with this approach by activating light-sensitive drugs deep in the body and suppressing tumor activity in vivo in animal models. The versatility in light delivery enabled by this approach extends the spatial and temporal precision of PDT to regions deep within the body.
High integrin α
V
β
6
affinity reached by hybrid domain deletion slows ligand-binding on-rate
Authors: Dong Xianchi , Zhao Bo , Lin Fu-Yang , Lu Chafen , Rogers Bruce N. , Springer Timothy A.
Published: January 2018

Significance

Integrins are complex multidomain adhesion molecules. We study how their affinity and binding kinetics for extracellular ligands are regulated, which is essential to enable integrins to communicate with the cytoskeleton. We show that the hybrid domain, which interfaces with the βI domain, strongly regulates affinity for ligand, which binds to a distal face of the βI domain. At high integrin affinity, the ligand binding on-rate goes down. We propose that integrins bind ligand in their low-affinity state, which has a wider ligand-binding pocket, and then convert to their high-affinity state, which has a tighter pocket.