bluuebunny/crossref_metadata_2025 huggingface dataset:
Elucidating the reaction pathway for ethene and propene formation in the methanol-to-hydrocarbons reaction over high silica H-Beta
Authors: Zhang Jie , Huang Zhihua , Li Peidong , Zhang Xiaomin , Zhang Xinzhi , Yuan Yangyang , Xu Lei
Published: April 2017

High silica H-Beta exhibits high propene selectivity in methanol conversion due to the participation of an olefins-based cycle and domination of higher methylbenzenes in an aromatics-based cycle.
Effect of methanol in controlling defunctionalization of the propyl side chain of phenolics from catalytic upstream biorefining
Authors: Ferrini Paola , Chesi Claudio , Parkin Nicholas , Rinaldi Roberto
Published: April 2017

In recent years, lignin valorization has gained upward momentum owing to advances in both plant bioengineering and catalytic processing of lignin. In this new horizon, catalysis is now applied to the ‘pulping process’ itself, creating efficient methods for lignocellulose fractionation or deconstruction (here referred to as Catalytic Upstream Biorefining or ‘CUB’). These processes render, together with delignified pulps, lignin streams of low molecular weight (Mw) and low molecular diversity. Recently, we introduced a CUB process based on Early-stage Catalytic Conversion of Lignin (ECCL) through H-transfer reactions catalyzed by RANEY® Ni. This approach renders a lignin stream obtained as a viscous oil, comprising up to 60 wt% monophenolic compounds (Mw < 250 Da). The remaining oil fraction (40 wt%) is mainly composed of lignin oligomers, and as minor products, holocellulose-derived polyols and lignin-derived species of high Mw (0.25–2 kDa). Simultaneously, the process yields a holocellulose pulp with a low content of residual lignin (<5 wt%). Despite the efficiency of aqueous solutions of 2-propanol as a solvent for lignin fragments and an H-donor, there is scant information regarding the CUB process carried out in the presence of primary alcohols, which often inhibit the catalytic activity of RANEY® Ni, as revealed in model compound studies performed at low temperature. Considering the composition of the lignin oils obtained from CUB based on ECCL, the processes commonly render ortho-(di)methoxy-4-propylphenol derivatives with a varied degree of defunctionalization of the propyl side chain. In this contribution, we present the role of the alcohol solvent (methanol or 2-propanol) and Ni catalyst (Ni/C or RANEY® Ni) in control over selectivity of phenolic products. The current results indicate that solvent effects on the catalytic processes could hold the key for improving control over the degree of functionalization of the propyl side-chain in the lignin oil obtained from CUB, offering new avenues for lignin valorization at the extraction step.
Protecting-group-free synthesis of haterumadienone- and puupehenone-type marine natural products
Authors: Wang Hong-Shuang , Li Hui-Jing , Wang Jun-Li , Wu Yan-Chao
Published: April 2017

The atom- and step-economical synthesis of seven puupehenone- and haterumadienone-type marine natural products without the use of protecting groups and transition metals has been achieved from the abundant feedstock chemical sclareolide in only 6 to 9 steps.
A new fluorescent sensor containing glutamic acid for Fe3+ and its resulting complex as a secondary sensor for PPi in purely aqueous solution
Authors: Li Ping , Wang Ying
Published: April 2017

A new fluorescence sensor L with benzimidazo[2,1-α]benz[de]isoquinoline-7-one as the fluorophore and glutamic acid moiety as the receptor was synthesized and characterized.
Electronic to protonic conduction switching in Cu2O nanostructured porous films: the effect of humidity exposure
Authors: Dhonge Baban P. , Ray Suprakas Sinha , Mwakikunga Bonex
Published: April 2017

In this paper, we present the first experimental evidence for electronic to protonic conduction switching in p-type semiconducting nanostructured cuprous oxide (Cu2O) porous films when exposed to humidity.
A comparative study of the mechanical, shape-memory, and degradation properties of poly(lactic acid) nanofiber and cellulose nanocrystal reinforced poly(mannitol sebacate) nanocomposites
Authors: Sonseca Águeda , Menes Olivia , Giménez Enrique
Published: April 2017

Composites based on elastomeric matrices and with enhanced mechanical behaviour at physiological temperatures useful for shape memory biodegradable implantable devices.
Role of hydrophilic groups in acid intercalated graphene oxide as a superionic conductor
Authors: Wakata Kosuke , Islam Md. Saidul , Karim Mohammad Razaul , Hatakeyama Kazuto , Rabin Nurun Nahar , Ohtani Ryo , Nakamura Masaaki , Koinuma Michio , Hayami Shinya
Published: April 2017

The role of hydrophilic groups in acid intercalated GO for proton conduction has been justified. The higher extents of adsorbed water due to the presence of hydrophilic groups are primarily responsible for offering enhanced proton conductivity.
Poly(ethylene terephthalate-co-isophthalate) synthesized via a Sb/Al bimetallic compound catalyst: the effect of the end groups on the properties of polyester
Authors: Zhang Fuchen , Wang Qiuxia , Wang Lipeng , Bai Yongping
Published: April 2017

γ-AlOOH can react with terminal carboxyl of PETI to form a terminal carboxyl aluminum coordination compound.
Preparation of functionalized partially unzipped carbon nanotube/polyimide composite fibers with increased mechanical and thermal properties
Authors: Cheng Yao , Zhang Shiyu , Li Juan , Sun Jun , Wang Jianjun , Qin Chuanxiang , Dai Lixing
Published: April 2017

Functionalized partially unzipped carbon nanotubes (f-PUCNTs) as reinforcements obviously improve mechanical and thermal properties of polyimide (PI)-based composite fibers.
Improvement of the selectivity to aniline in benzene amination over Cu/TS-1 by potassium
Authors: Nan Mi , Luo Yuecheng , Li Guiying , Hu Changwei
Published: April 2017

Two different methods of introducing potassium into Cu/TS-1 were conducted and the catalysts obtained showed a rather different catalytic activity in the ammoxidation of benzene to aniline.
Multi-walled carbon nanotubes induced a controllable TiO2morphology transformation for high-rate and long-life lithium-ion batteries
Authors: Xia Yu , Xiong Wan-Sheng , Jiang Yun , Sun Weiwei , Sang Hong-Qian , He Rong-Xiang , Tai Qidong , Chen Bolei , Liu Yumin , Zhao Xing-Zhong
Published: April 2017

A facile strategy to achieve the controllable morphology transformation of TiO2induced by the introduction of multi-walled carbon nanotubes has been demonstrated.
Dual-targeted peptide-conjugated multifunctional fluorescent probe with AIEgen for efficient nucleus-specific imaging and long-term tracing of cancer cells
Authors: Cheng Yong , Sun Chunli , Ou Xiaowen , Liu Bifeng , Lou Xiaoding , Xia Fan
Published: April 2017

Precisely targeted transportation of a long-term tracing regent to a nucleus with low toxicity is one of the most challenging concerns in revealing cancer cell behaviors.
Structural characterization of framework–gas interactions in the metal–organic framework Co2(dobdc) by in situ single-crystal X-ray diffraction
Authors: Gonzalez Miguel I. , Mason Jarad A. , Bloch Eric D. , Teat Simon J. , Gagnon Kevin J. , Morrison Gregory Y. , Queen Wendy L. , Long Jeffrey R.
Published: April 2017

In situ single-crystal X-ray diffraction experiments enable the direct observation of weak metal–gas interactions in a metal–organic framework.
Molecular heterogeneous catalysts derived from bipyridine-based organosilica nanotubes for C–H bond activation
Authors: Zhang Shengbo , Wang Hua , Li Mei , Han Jinyu , Liu Xiao , Gong Jinlong
Published: April 2017

The present study described bipyridine-based organosilica nanotubes with ∼50 nm length; these nanotubes provide highly active and robust molecular iridium heterogeneous catalysts for C–H oxidation of heterocycles and cycloalkanes as well as C–H borylation of arenes.
Scalable perovskite/CIGS thin-film solar module with power conversion efficiency of 17.8%
Authors: Paetzold U. W. , Jaysankar M. , Gehlhaar R. , Ahlswede E. , Paetel S. , Qiu W. , Bastos J. , Rakocevic L. , Richards B. S. , Aernouts T. , Powalla M. , Poortmans J.
Published: April 2017

All-thin film perovskite/CIGS multijunction solar modules, combining a semi-transparent perovskite top solar module stacked on a CIGS bottom solar module, are a promising route to surpass the efficiency limits of single-junction thin-film solar modules.
In situ nitrogen-doped hollow-TiO2/g-C3N4 composite photocatalysts with efficient charge separation boosting water reduction under visible light
Authors: Shi Xiaowei , Fujitsuka Mamoru , Lou Zaizhu , Zhang Peng , Majima Tetsuro
Published: April 2017

The visible-light-driven water splitting process is highly attractive for alternative energy utilization, while developing efficient, earth-abundant, and environmentally friendly photocatalysts for the hydrogen evolution reaction has remained a major challenge.
A novel reusable superhydrophilic NiO/Ni mesh produced by a facile fabrication method for superior oil/water separation
Authors: Yu Zhenwei , Yun Frank F. , Gong Zhiyuan , Yao Qiang , Dou Shixue , Liu Kesong , Jiang Lei , Wang Xiaolin
Published: April 2017

A low-cost and reusable novel superhydrophilic and underwater superoleophobic NiO/Ni mesh with a micro/nanoscale hierarchical structure exhibits superior oil/water separation in harsh environments.
Systematic evaluation of structure–property relationships in heteroacene – diketopyrrolopyrrole molecular donors for organic solar cells
Authors: Loser Stephen , Lou Sylvia J. , Savoie Brett M. , Bruns Carson J. , Timalsina Amod , Leonardi Matthew J. , Smith Jeremy , Harschneck Tobias , Turrisi Riccardo , Zhou Nanjia , Stern Charlotte L. , Sarjeant Amy A. , Facchetti Antonio , Chang Robert P. H. , Stupp Samuel I. , Ratner Mark A. , Chen Lin X. , Marks Tobin J.
Published: April 2017

Understanding the effects of molecular shape on active layer charge transport in OPVs.
Hollow-ZIF-templated formation of a ZnO@C–N–Co core–shell nanostructure for highly efficient pollutant photodegradation
Authors: Chen Huirong , Shen Kui , Chen Junying , Chen Xiaodong , Li Yingwei
Published: April 2017

A novel ZnO@C–N–Co core–shell nanostructure was successfully prepared by the direct pyrolysis of a hollow Zn/Co–ZIF matrix, which showed a significantly improved performance for the model pollutant photodegradation due to the highly synergistic effects from C–N–Co shell and ZnO core.
A luminescent lanthanide MOF for selectively and ultra-high sensitively detecting Pb2+ ions in aqueous solution
Authors: Ji Guanfeng , Liu Jingjuan , Gao Xuechuan , Sun Wei , Wang JinZeng , Zhao Shenglu , Liu ZhiLiang
Published: April 2017

An amazing millimeter-sized lanthanide metal–organic framework, Tb-MOF, was synthesized. Due to the larger volume, Pb2+ ions can be sensitively and selectively detected by visible fluorescence quenching of Tb-MOF. Additionally, a Tb-MOF crystal film with an ultra-high recognition ability of Pb2+ ions has been fabricated successfully.
Evolution of morphology and open-circuit voltage in alloy-energy transfer coexisting ternary organic solar cells
Authors: Xia Benzheng , Yuan Liu , Zhang Jianqi , Wang Zaiyu , Fang Jin , Zhao Yifan , Deng Dan , Ma Wei , Lu Kun , Wei Zhixiang
Published: April 2017

Alloy-like domain structure and energy transfer coexist in the ternary system, in which the maximum PCE of 11.1% is obtained.
Facile patterning using dry film photo-resists for flexible electronics: Ag nanowire networks and carbon nanotube networks
Authors: An Chee-Hong , Kim Sunho , Lee Hoo-Jeong , Hwang Byungil
Published: April 2017

The Ag nanowire and CNT networks are patterned with a pattern width up to 30 μm by using dry film photo resists (DFRs). The systematic characterization of the electrical and mechanical properties of the patterned Ag nanowire networks revealed pattern width dependent property changes.
Terminal π–π stacking determines three-dimensional molecular packing and isotropic charge transport in an A–π–A electron acceptor for non-fullerene organic solar cells
Authors: Han Guangchao , Guo Yuan , Song Xiaoxian , Wang Yue , Yi Yuanping
Published: April 2017

Three-dimensional molecular packing and isotropic charge transport can be achieved through local π–π stacking between terminal acceptor units for A–π–A electron acceptors toward high-performance non-fullerene organic solar cells.
The association between etanercept serum concentration and psoriasis severity is highly age-dependent
Authors: Detrez Iris , Van Steen Kristel , Segaert Siegfried , Gils Ann
Published: April 2017

The association between etanercept serum concentration and psoriasis disease severity is poorly investigated, and currently etanercept serum concentration monitoring that is aiming to optimize the psoriasis treatment lacks evidence. In this prospective study, we investigated the relation between etanercept exposure and disease severity via measuring etanercept concentrations at five consecutive time points in 56 psoriasis patients. Disease severity assessments included the Psoriasis Area and Severity Index (PASI), body surface area (BSA) and Physician Global Assessment (PGA), and etanercept and anti-etanercept antibody concentrations were determined every 3 months for a period of 1 year. The present study demonstrated that the association between etanercept concentration and psoriasis severity is age-dependent: when patients were stratified into three groups, patients in the youngest age group (–50 years) showed a lower PASI at a higher etanercept concentration (β = –0.26), whereas patients in the oldest age group (+59 years) showed the opposite trend (β =0.22). Similar age effects were observed in the relation of etanercept concentration with BSA (P=0.02) and PGA (P=0.02). The influence of age and length of time in therapy on the etanercept concentration–disease severity relation was unaffected by body mass index (BMI) or any other possible confounder. Incidence of anti-etanercept antibodies was low (2%). The age-dependent relation between etanercept serum concentrations is both unexpected and intriguing and needs further investigation.
Asynchronous operation characteristics and soft‐starting method for the brushless doubly‐fed motor
Authors: Kong Ming , Wang Xuefan , Li Zhenping , Nie Pengcheng
Published: April 2017

The brushless doubly‐fed motor (BDFM) is versatile and can perform under several modes of operation. Other than the commonly used doubly‐fed mode, BDFM can also operate in an asynchronous mode wherein the control winding of the motor is short circuited. The proposed study first analysed the mechanical characteristics of BDFM operation under this mode, whereby it was noted that there exist two induction torque components corresponding to different pole pairs within the motor. The motor, therefore, behaved as a conventional induction machine. Based on the above analysis and by introducing the concept of equivalent resistance of the machine‐side inverter, an asynchronous soft‐starting method for BDFM is proposed herein. By switching one side of the inverter bridge arms to the off state and adjusting the duty cycle on the other side, a controllable equivalent resistance is obtained and inserted into the control winding of BDFM. Consequently, the starting characteristic of BDFM can be improved to achieve soft start‐up of the motor. Finally, experiments were conducted on a 30 kW BDFM prototype, of which, the results verify the accuracy of the torque analysis and improved performance of the proposed soft‐starting method.
Optical scheme of conversion of a positionally encoded decimal digit to frequency encoded Boolean form using Mach–Zehnder interferometer‐based semiconductor optical amplifier
Authors: Saha Subhendu , Biswas Subhendu , Mukhopadhyay Sourangshu
Published: April 2017

The conversion of decimal number to its equivalent binary one and vice‐versa is very important in the field of electronic/optical computing and data processing system. There are so many well established methods for this conversion. In this study, the authors propose a new scheme for optical conversion of a decimal number to its frequency encoded binary equivalent using tree architecture‐based system and frequency‐encoding principle. To implement the above conversion, some optical non‐linear switches, such as Mach–Zehnder interferometer‐based semiconductor optical amplifier (SOA), reflecting SOA based on SOA, have been used to get frequency encoded response.
Metal-Free Oxidative C=C Bond Cleavage of Electron-Deficient Enamines Promoted by tert-Butyl Hydroperoxide
Authors: Adib Mehdi , Pashazadeh Rahim , Gohari Seyed , Shahsavari Fatemeh
Published: April 2017

A novel tert-butyl hydroperoxide (TBHP)-promoted oxidative C=C double-bond cleavage of enamines is described. Heating a solution of an electron-deficient enamine in chlorobenzene at 80 °C in the presence of TBHP for two hours led to cleavage of the C=C bond. This study offers a new strategy to carry out C=O double-bond formation by the use of TBHP.
Direct Introduction of an N,N′-Nonsubstituted Carboxamidine Group by Grignard Addition to Silylated Cyanamide
Authors: Guethner Thomas , Huber Eva , Sans Juergen , Thalhammer Franz
Published: April 2017

A new, widely applicable method to substitute a halogen atom by a nonsubstituted carboxamidine group is presented. Grignard addition to N,N′-bis-trimethylsilylcarbodiimide gives amidinates, which split off the silyl groups during standard aqueous workup. The corresponding amidines are obtained in high yield with high selectivity. Examples for purification procedures are given.
Hybrid Strategy for High-Risk Neonates with Interrupted Aortic Arch: A Can Well Worth Kicking?
Authors: Kapravelou Eva , Anderson David , Morgan Gareth
Published: April 2017

The use of hybrid techniques to avoid neonatal cardiopulmonary bypass in high-risk individuals is well reported in the setting of hypoplastic left heart syndrome. We describe the use of that technique as a bridging procedure in high-risk neonates with an interrupted aortic arch. We report three cases where hybrid branch pulmonary artery banding and ductal stent implantation has been successfully used to defer complete repair, allowing recovery, maturity, and weight gain. This strategy may be considered for patients deemed at high risk for primary neonatal repair.
Model for the alpha and beta shear-mechanical properties of supercooled liquids and its comparison to squalane data
Authors: Hecksher Tina , Olsen Niels Boye , Dyre Jeppe C.
Published: April 2017

This paper presents data for supercooled squalane’s frequency-dependent shear modulus covering frequencies from 10 mHz to 30 kHz and temperatures from 168 K to 190 K; measurements are also reported for the glass phase down to 146 K. The data reveal a strong mechanical beta process. A model is proposed for the shear response of the metastable equilibrium liquid phase of supercooled liquids. The model is an electrical equivalent-circuit characterized by additivity of the dynamic shear compliances of the alpha and beta processes. The nontrivial parts of the alpha and beta processes are each represented by a “Cole-Cole retardation element” defined as a series connection of a capacitor and a constant-phase element, resulting in the Cole-Cole compliance function well-known from dielectrics. The model, which assumes that the high-frequency decay of the alpha shear compliance loss varies with the angular frequency as ω−1/2, has seven parameters. Assuming time-temperature superposition for the alpha and beta processes separately, the number of parameters varying with temperature is reduced to four. The model provides a better fit to the data than an equally parametrized Havriliak-Negami type model. From the temperature dependence of the best-fit model parameters, the following conclusions are drawn: (1) the alpha relaxation time conforms to the shoving model; (2) the beta relaxation loss-peak frequency is almost temperature independent; (3) the alpha compliance magnitude, which in the model equals the inverse of the instantaneous shear modulus, is only weakly temperature dependent; (4) the beta compliance magnitude decreases by a factor of three upon cooling in the temperature range studied. The final part of the paper briefly presents measurements of the dynamic adiabatic bulk modulus covering frequencies from 10 mHz to 10 kHz in the temperature range from 172 K to 200 K. The data are qualitatively similar to the shear modulus data by having a significant beta process. A single-order-parameter framework is suggested to rationalize these similarities.
Fabrication and evaluation of plasmonic light-emitting diodes with thin p-type layer and localized Ag particles embedded by ITO
Authors: Okada N. , Morishita N. , Mori A. , Tsukada T. , Tateishi K. , Okamoto K. , Tadatomo K.
Published: April 2017

Light-emitting diodes (LEDs) have been demonstrated with a thin p-type layer using the plasmonic effect. Optimal LED device operation was found when using a 20-nm-thick p+-GaN layer. Ag of different thicknesses was deposited on the thin p-type layer and annealed to form the localized Ag particles. The localized Ag particles were embedded by indium tin oxide to form a p-type electrode in the LED structure. By optimization of the plasmonic LED, the significant electroluminescence enhancement was observed when the thickness of Ag was 9.5 nm. Both upward and downward electroluminescence intensities were improved, and the external quantum efficiency was approximately double that of LEDs without the localized Ag particles. The time-resolved photoluminescence (PL) decay time for the LED with the localized Ag particles was shorter than that without the localized Ag particles. The faster PL decay time should cause the increase in internal quantum efficiency by adopting the localized Ag particles. To validate the localized surface plasmon resonance coupling effect, the absorption of the LEDs was investigated experimentally and using simulations.
Effect of NaZn/Nai ratio on structural, optical, and electrical properties of Na-doped ZnO thin films
Authors: Shen Hao , Zhao Xiaoru , Duan Libing , Liu Ruidi , Li Hui , Wang Bihan
Published: April 2017

In this paper, Na-doped ZnO (NZO) thin films were prepared via a dip-coating sol-gel method with Na doping content in a range of 0 at. %–3 at. %. X-ray photoelectron spectroscopy analysis showed that the NaZn/Nai ratio (r) increased with Na doping contents from 1 at. %–3 at. %. The effect of the NaZn/Nai ratio on the structural, optical, and electrical properties of NZO thin films was investigated. As the NaZn/Nai ratio increased, the lattice constant exhibited a continuous increase and resulted in the presence of increasing compressive stress in the NZO films. When the NaZn/Nai ratio was less than 1 (r<1), the electron concentration of NZO films increased continuously. However, when r>1, it decreased. The Hall mobility was mainly limited by ionized impurity scattering and displayed a decrease trend with the increasing NaZn/Nai ratio. Due to the Burstein-Moss effect, the optical energy band gaps (Eg) of NZO films got slightly enlarged as compared with that of the undoped ZnO film. Considering the relationship between the Burstein-Moss shift and the carrier concentration, the enlargement of Eg was actually determined by the NaZn/Nai ratio as well as the doping content.
Semi-empirical “leaky-bucket” model of laser-driven x-ray cavities
Authors: Moody J. D. , Landen O. L. , Divol L. , LePape S. , Michel P. , Town R. P. J. , Hall G. , Widmann K. , Moore A.
Published: April 2017

A semi-empirical analytical model is shown to approximately describe the energy balance in a laser-driven x-ray cavity, such as a hohlraum, for general laser pulse-shapes. Agreement between the model and measurements relies on two scalar parameters, one characterizes the efficiency of x-ray generation for a given laser power and the other represents a characteristic power-loss rate. These parameters, once obtained through estimation or optimization for a particular hohlraum design, can be used to predict either the x-ray flux or the coupled laser power time-history in terms of other quantities for similar hohlraum designs. The value of the model is that it can be used as an approximate “first-look” at hohlraum energy balance prior to a more detailed radiation hydrodynamic modeling.
Thermally induced age hardening in tough Ta-Al-N coatings via spinodal decomposition
Authors: Mikula M. , Sangiovanni D. G. , Plašienka D. , Roch T. , Čaplovičová M. , Truchlý M. , Satrapinskyy L. , Bystrický R. , Tonhauzerová D. , Vlčková D. , Kúš P.
Published: April 2017

We combine experiments and ab initio density functional theory calculations to investigate the evolution in structural and mechanical properties of TaAlN coatings as a function of the annealing temperature T. Formation of coherent cubic TaN- and AlN-rich nanometer-size domains, occurring during the initial stage of thermally induced phase separation within cubic NaCl-type (B1) TaAlN solid solutions, yields a monotonic increase in hardness from 29 GPa (as deposited coatings) up to a maximum of 35 GPa (+17%) reached after annealing at 1000 °C. Further thermal treatment at T > 1000 °C leads to the transformation of metastable cubic domains into stable hexagonal TaNx and wurtzite AlN phases, thus resulting in hardness reductions. A comparison of our results with those reported in the literature reveals that TaAlN coatings are at least as hard while considerably less stiff (lower elastic moduli) than TiAlN coatings, thus indicating a substantial increase in toughness achieved upon replacing Ti with Ta in the host lattice. Present findings suggest that cubic TaAlN solid solutions are promising candidates for applications in protective coatings possessing both high-temperature hardness and toughness.
Effect of annealing atmosphere pO2 on leakage current in 80(Bi0.5Na0.5)TiO3-20(Bi0.5K0.5)TiO3 piezoelectric thin films
Authors: Walenza-Slabe J. , Gibbons B. J.
Published: April 2017

Ferroelectric 80(Bi0.5Na0.5)TiO3–20(Bi0.5K0.5)TiO3 thin films were fabricated by chemical solution deposition on Pt/TiO2/SiO2/Si substrates. Films were post-annealed after crystallization at four different oxygen partial pressures (pO2): O2, air, N2, and H2/N2, given by order of decreasing pO2. In general, post-annealing in more oxidizing atmospheres will decrease the concentration of positive charged oxygen vacancies, thus either increasing the number of electron holes or decreasing the number of electrons. In principle, this allows for the determination of the majority electronic carrier type by studying the conductivity of the films. The DC conductivity was measured as a function of electric field, and the results were found to be consistent with n-type conduction. Also, while the leakage current is generally space charge-limited, there are several key features of the current density-electric field characteristics which were affected by the post-anneal pO2. For instance, while remaining space charge is limited, the characteristics show that the trap energy distribution changes with the post-annealing treatment. The H2/N2 post-annealed films showed a reduction in the dielectric constant and ferroelectric polarization relative to the O2 post-annealed films.
Identification of microscopic domain wall motion from temperature dependence of nonlinear dielectric response
Authors: Mokrý Pavel , Sluka Tomáš
Published: April 2017

It is known that the permittivity of ferroelectric polydomain films and single crystals in weak electric fields is strongly enhanced by the reversible movement of pinned domain walls. Two mechanisms of the movement exist: first, the bending of free segments of the domain wall and second the planar movement of the domain wall as a whole. In this work, we theoretically demonstrate that it is possible to determine the dominant mechanism of the reversible domain wall movement by means of a temperature measurement of a nonlinear macroscopic dielectric response. In addition, we demonstrate that using this approach, it is possible to obtain quantitative information on the microscopic distribution of the pinning centers. Thus, we suggest that this concept may serve as a simple and useful characterisation tool in the process of development of high-permittivity materials.
Electro-optical hysteresis and bistability in the ring-cavity tunneling-collector transistor laser
Authors: Feng M. , Holonyak N. , Wu M. K. , Tan F.
Published: April 2017

Bistable devices are fundamental to digital electronics as building blocks of switches, logic gates, and memory in computer systems. We demonstrate here transistor lasers exhibiting both electrical and optical hystereses with sharp square-corner current switching and different voltage thresholds in the collector IC–VCE and optical L–VCE family of characteristics. The electro-optical hysteresis is explained by the different switching paths of electron-hole (e-h) and photon interactions involving cavity coherent and incoherent energy states employing intracavity photon-assisted tunneling at the collector junction and spontaneous/stimulated e-h recombination at the base quantum-well. The electro-optical bistability of the transistor laser possesses a unique property of voltage (field) modulation and the basis for high speed optical logic processors.
Time-resolved image plane off-axis digital holography
Authors: Petrov N. V. , Putilin S. E. , Chipegin A. A.
Published: April 2017

In this work, we demonstrate off-axis image-plane digital holography for measuring ultrafast processes with high temporal resolution. The proposed image-plane holographic configuration in conjunction with numerical post-processing procedures allows us to neglect the walk-off effect in the off-axis arrangement by synthesizing spatial phase distribution with the whole field of view from separate fragments and to increase the spatial resolution by means of a telecentric system with adjustable magnification. We have analyzed temporal resolution taking into account all dispersing elements that increase the duration of the pulses being propagated through the optical setup. The technique was approved with experiment on measuring the dynamics of the refractive index, induced by laser filamentation in air.
Long-term recovery from fire by a population of honey possums (Tarsipes rostratus) in the extreme south-west of Western Australia
Authors: Bradshaw S. D. , Bradshaw F. J.
Published: April 2017

The impact of two fires, six years apart, on the long-term recovery of a population of honey possums (Tarsipes rostratus) in the extreme south-west of Western Australia was documented over a 23-year period. Recovery was relatively rapid after the first fire, with catch rates reaching 78% of precatch levels within six years, but was much slower following the second fire in April 1999. Regression analysis estimates that full recovery to prefire catch rates and densities would take 25.6 years. The spread of Phytophthora cinnamomi (dieback) throughout the study area has severely impacted Banksia ilicifolia trees, which are the honey possums’ primary food source, and the impact has been greater in the burnt than unburnt areas. Analysis of catch-per-unit-effort and density of individual honey possums over the whole 29-year period of the study shows that numbers have not declined in the long-unburnt southern area of the study site, despite the spread of dieback and loss of banksia trees. The data are discussed in relation to the impact of fire on other vertebrate species that have specific habitat requirements. Given predictions of increasing fire frequencies due to climate change and an increased utilisation of prescribed burning to protect human life and property, it is imperative that management of areas harbouring honey possums be protected from too-frequent fire if this iconic species is to persist.
Regulating plant physiology with organic electronics
Authors: Poxson David J. , Karady Michal , Gabrielsson Roger , Alkattan Aziz Y. , Gustavsson Anna , Doyle Siamsa M. , Robert Stéphanie , Ljung Karin , Grebe Markus , Simon Daniel T. , Berggren Magnus
Published: April 2017

Significance

Hormones play a crucial role in the coordination of the physiological processes within and between the cells and tissues of plants. However, due to a lack of capable technologies, direct and dynamic interactions with plants’ hormone-signaling systems remains limited. Here, we demonstrate the use of an organic electronic device—the organic electronic ion pump—to deliver the plant hormone auxin to the living root tissues of
Arabidopsis thaliana
seedlings, inducing differential concentration gradients and modulating plant physiology. Electronically regulated transport of aromatic structures such as auxin in an organic electronic device was achieved by synthesis of a previously unidentified class of dendritic polyelectrolyte. Such bioelectronic technology opens the door for precise, electronically mediated control of a plant’s growth and development.
Structural features and lipid binding domain of tubulin on biomimetic mitochondrial membranes
Authors: Hoogerheide David P. , Noskov Sergei Y. , Jacobs Daniel , Bergdoll Lucie , Silin Vitalii , Worcester David L. , Abramson Jeff , Nanda Hirsh , Rostovtseva Tatiana K. , Bezrukov Sergey M.
Published: April 2017

Significance

Tubulin has emerged as a highly unexpected component of mitochondrial membranes involved in regulation of membrane permeability. This discovery has reawakened interest in the nature of the tubulin–membrane interaction to answer a new question: How does tubulin, a cytosolic protein famous for its role in microtubule structure and dynamics, come to target mitochondrial membranes? Here, using a combination of five biophysical methods, we study peripheral binding of tubulin to biomimetic membranes of different lipid compositions. We conclude that tubulin distinguishes between lamellar and nonlamellar lipids through a highly conserved amphipathic binding motif. Specifically, α-tubulin targets cell and organelle membranes by sensing lipid-packing defects via an amphipathic α-helix, with broad consequences for both normal cellular function and disease.
Activation of NLRP3 inflammasome complex potentiates venous thrombosis in response to hypoxia
Authors: Gupta Neha , Sahu Anita , Prabhakar Amit , Chatterjee Tathagata , Tyagi Tarun , Kumari Babita , Khan Nilofar , Nair Velu , Bajaj Nitin , Sharma Manish , Ashraf Mohammad Zahid
Published: April 2017

Significance

Hypoxia predisposes otherwise healthy individuals to venous thrombosis, but the underlying mechanism has been unclear. Our study revealed a causal role for nucleotide binding domain, leucine-rich-containing family, pyrin domain containing 3 (NLRP3) inflammasome and IL-1β during hypoxia-induced venous thrombosis. We further show a direct association between NLRP3 and hypoxia-inducible factor 1-alpha (HIF-1α) during these conditions. Specific interventions within the hypoxia–HIF-1α–NLRP3–IL-1β axis in the venous milieu significantly reduced venous thrombosis in our animal model. Notably, we also observed modulation of similar pathways in patients diagnosed with altitude-induced venous thrombosis. Our study thus revealed thrombosis at high altitude to be centrally regulated by a complex network of coagulatory and inflammatory processes, critically linked through HIF-1α.
Wear behaviour at 600°C of surface engineered low-alloy steel containing TiC particles
Authors: Md Idriss A. N. , Maleque M. A. , Yaacob I. I. , Nasir R. M. , Mridha S. , Baker T. N.
Published: April 2017

The work aimed to develop surfaces that could resist wear at high temperatures, thus achieving a prolonged component life. Surface modification of a low-alloy steel by incorporating TiC particles has been undertaken by melting the surface using a tungsten inert gas torch. The dry sliding wear behaviour at 600°C of the original and modified surfaces was compared. Microscopic examination of both surfaces showed glazed layers across the wear tracks, with differing amounts of oxide and homogeneity. Extensive wear occurred on the steel surface, which showed deformation of the wear scar tracks and a steadily increased friction coefficient. The TiC addition reduced the wear loss, coinciding with a glazed layer 33% thinner than that on the low-alloy steel sample.
Heat treatment of plasma sprayed alumina-chromia composite coatings
Authors: Dhakar Balmukund , Namdeo Akshay , Chatterjee Satyajit , Sabiruddin Kazi
Published: April 2017

Atmospheric plasma spray technique is used to develop alumina-based coatings by spraying mechanically blended alumina-chromia feedstock with chromia content varying from 1–6 wt-%. The influence of annealing temperature (900–1200°C) on the phases formed in the coatings is also studied. Phases present in the coatings are analysed and quantified using X-ray diffraction and Rietveld refinement, respectively. Microstructures of the coating cross sections are studied under scanning electron microscope. Wear rate of the annealed coatings are evaluated by linear reciprocating wear tests. The adhesion strength of the coatings is also estimated by ASTM C1624 standard. The results indicate that the increase in annealing temperature causes rise in transformation of metastable phases of alumina into stable α-alumina. The minimum annealing temperature required to complete this transformation is estimated for each coating. The lowest specific wear rate is observed at 1150°C temperature and with 4 wt-% chromia content. The significant change in the trend of wear rate observed at the annealing temperature of 1200°C can be attributed to formation of large amount of cracks in the coatings. Adhesion strength of the coating improves with increasing chromia content. However, with increase in annealing temperature the coating adhesion decreases significantly due to the formation of cracks.
Enteropathy-associated T cell lymphoma subtypes are characterized by loss of function of SETD2
Authors: Moffitt Andrea B. , Ondrejka Sarah L. , McKinney Matthew , Rempel Rachel E. , Goodlad John R. , Teh Chun Huat , Leppa Sirpa , Mannisto Susanna , Kovanen Panu E. , Tse Eric , Au-Yeung Rex K.H. , Kwong Yok-Lam , Srivastava Gopesh , Iqbal Javeed , Yu Jiayu , Naresh Kikkeri , Villa Diego , Gascoyne Randy D. , Said Jonathan , Czader Magdalena B. , Chadburn Amy , Richards Kristy L. , Rajagopalan Deepthi , Davis Nicholas S. , Smith Eileen C. , Palus Brooke C. , Tzeng Tiffany J. , Healy Jane A. , Lugar Patricia L. , Datta Jyotishka , Love Cassandra , Levy Shawn , Dunson David B. , Zhuang Yuan , Hsi Eric D. , Dave Sandeep S.
Published: April 2017

Enteropathy-associated T cell lymphoma (EATL) is a lethal, and the most common, neoplastic complication of celiac disease. Here, we defined the genetic landscape of EATL through whole-exome sequencing of 69 EATL tumors. SETD2 was the most frequently silenced gene in EATL (32% of cases). The JAK-STAT pathway was the most frequently mutated pathway, with frequent mutations in STAT5B as well as JAK1, JAK3, STAT3, and SOCS1. We also identified mutations in KRAS, TP53, and TERT. Type I EATL and type II EATL (monomorphic epitheliotropic intestinal T cell lymphoma) had highly overlapping genetic alterations indicating shared mechanisms underlying their pathogenesis. We modeled the effects of SETD2 loss in vivo by developing a T cell–specific knockout mouse. These mice manifested an expansion of γδ T cells, indicating novel roles for SETD2 in T cell development and lymphomagenesis. Our data render the most comprehensive genetic portrait yet of this uncommon but lethal disease and may inform future classification schemes.
Necessitation and Justification in Kant’s Ethics
Authors: Timmons Mark
Published: April 2017

This chapter offers an interpretation of Kant’s claim that hypothetical imperatives are analytic and categorical imperatives are synthetic. This distinction applies comfortably to propositions having subject/predicate form, but imperatives do not have that form. So in what sense can the distinction apply? The key to an answer is Kant’s notion of practical necessitation that is unpacked by reference to full rational agency. The chapter explains how the proposed interpretation of imperatives bears on the question of the justification of Kant’s fundamental moral principle, the categorical imperative that is featured in Section III of his 1785 Groundwork of the Metaphysics of Morals, where it is important to distinguish epistemological questions about the truth, scope, and authority of practical statements.
Motive and Rightness in Kant’s Ethical System
Authors: Timmons Mark
Published: April 2017

Kant distinguishes actions that conform to duty and are thus dutiful from an action’s moral worth. Moral worth, for Kant, depends on whether one’s sole and sufficient motive for a dutiful action is respect for the moral law. Kant’s well-known case of the shopkeeper who gives inexperienced customers correct change from the motive of self-interest, performs a dutiful action, but one lacking in moral worth. This example suggests that one’s motive does not affect the rightness or dutifulness of an action; that an action’s deontic status is independent of one’s motive (the independence thesis, IT). However, some interpreters of Kant argue that the respect for law motive is part of the content of the ethical duties featured in the 1797 Metaphysics of Morals (the motive content thesis, MCT). This chapter argues MCT is false, but that IT is also false because motives such as malice can affect an action’s deontic status.
Love of Honor, Emulation, and the Psychology of the Devilish Vices
Authors: Timmons Mark
Published: April 2017

This chapter looks to the Lectures in Ethics for remarks about the psychology of the “devilish vices” of envy, ingratitude, and Schadenfreude. The question guiding this examination is this: is there a common underlying psychological account of the emergence of these vices? After developing Kant’s conception of the acquisition of the virtues, the focus is on each of the vices in question with the aim of explaining, against the background of virtue acquisition, how each of the devilish vices emerges. Virtue involves proper love of honor and emulation is an innate instinct whose proper role is to stimulate self-improvement by comparing oneself to select others. However, without a proper sense of honor that requires comparing oneself with the moral law, the self-other comparison involved in emulation can lead one to succumb to one of the vices. The conclusion is that there is a similar psychology underlying this cluster of vices.
Local pivotal strategies for sparse matrices
Authors: Duff I. S. , Erisman A. M. , Reid J. K.
Published: April 2017

We consider local strategies for pivot selection, that is, where decisions are made at each stage of the factorization without regard to how they might affect later stages. They include minimum degree for symmetric matrices, Markowitz’ strategy for unsymmetric matrices, minimum fill-in, and simpler strategies. We discuss the inclusion of numerical pivoting. We consider taking advantage of sparsity in the right-hand side and of wanting only part of the solution.
Implementing Gaussian elimination with symbolic factorize
Authors: Duff I. S. , Erisman A. M. , Reid J. K.
Published: April 2017

We discuss implementation techniques for sparse Gaussian elimination, based on analysis of the sparsity pattern without regard to numerical values. This includes a discussion of data structures for pivot selection, the use of cliques, and the use of both dynamic and static data structures. We examine the division of the solution into the distinct phases of reordering, symbolic factorization, numerical factorization, and solution, indicating the high efficiency with which these steps can now be performed.
Other sparsity-oriented issues
Authors: Duff I. S. , Erisman A. M. , Reid J. K.
Published: April 2017

We consider solving a problem that is closely related to one that we have previously solved or whose parts have previously been solved. We study backward error analysis for sparse problems, obtaining entries of the inverse of a sparse matrix, sparsity in nonlinear problems, solution methods based on orthogonal transformations, and hybrid methods that combine iterative and direct methods.
The Effect of Rubric-Guided, Focused, Personalized Coaching Sessions and Video-Recorded Presentations on Teaching Skills Among Fourth-Year Medical Students: A Pilot Study
Authors: Tchekmedyian Vatche , Shields Helen M. , Pelletier Stephen R. , Pazo Valeria C.
Published: April 2017

Problem

As medical students become residents, teaching becomes an expected and integral responsibility. Yet, training-for-teaching opportunities are lacking. In 2014, the authors designed a pilot study using rubric-guided, focused, personalized coaching sessions and video-recorded presentations to improve student teaching skills among fourth-year students at Harvard Medical School.

Approach

In 2014–2015, the authors recruited students from an elective on how to tutor preclinical students for the pilot, which consisted of four phases: a precoaching teaching presentation, a 30- to 45-minute coaching session, a postcoaching teaching presentation, and blinded reviewer ratings. Students’ pre- and postcoaching presentations were video recorded. Using a scoring rubric for 15 teaching skills, students rated their pre- and postcoaching videos. Blinded reviewers also rated the pre- and postcoaching presentations using the same rubric with an additional category to gauge their overall impression.

Outcomes

Fourteen students completed all four phases of the pilot. Students’ ratings demonstrated statistically significant improvement in several teaching skills, including presentation content (P < .001), rate of speech (P = .001), and opening statement and learning objectives (P = .004). Blinded reviewers’ ratings demonstrated statistically significant improvements in several teaching skills, including opening statement and learning objectives (P < .001), overall impression (P = .001), and conclusion and summary of learning objectives (P = .004). Students provided largely positive comments on the interventions.

Next Steps

The authors will work toward addressing limitations in the rubric, using coaching in different teaching settings, addressing the interventions’ generalizability, training coaches, and performing additional evaluations.
Distally Based Sural Artery Peroneus Flap (DBSPF) for Foot and Ankle Reconstruction
Authors: Ebrahiem Ahmed Ali , Manas Raj Kumar , Vinagre Gustavo
Published: April 2017

Background:

Reconstruction of soft-tissue defects in lower third of leg, ankle, and foot has been a challenge and reconstructive surgeons have been trying to innovate different flaps. To solve this issue, we propose a distally based sural artery peroneus flap (DBSPF) in which we include superficial portion of the peroneus brevis muscle and its blood supply with the peroneal artery distally. The aim of this study was to evaluate the functional outcome and its usefulness over conventional distal sural artery flap or other local options available.

Methods:

This is a case series of 20 patients that include a DBSPF that was done for defects around ankle, distal leg, and foot caused by trauma or tumor ablation within the period of June 2013 to March 2015 in Kasralainy Hospital, Cairo. All cases were evaluated according to flap vascularity, distal reach of flap, aesthetic outcome, and donor-site morbidity.

Results:

All flaps survived. One flap developed venous congestion that subsided spontaneously with limb elevation. The flap dimension ranged from 42 cm to 442 cm2, and it reached the midfoot easily. The pivot point was kept as low as 2–6 cm from lateral malleolus according to location of perforators. The ankle stability was maintained, and the desired aesthetic outcome was achieved.

Conclusions:

The DBSPF is an addition to the armamentarium in plastic surgery for defects around ankle, distal leg, and foot. It is an easy and swift procedure as compared with complex microsurgical reconstruction.