bluuebunny/crossref_metadata_2025 huggingface dataset:
Impaired hippocampal-cortical coupling but preserved local synchrony during sleep in APP/PS1 mice modeling Alzheimer’s disease
Authors: Zhurakovskaya E. , Ishchenko I. , Gureviciene I. , Aliev R. , Gröhn O. , Tanila H.
Published: March 2019

Sleep, in addition to its brain restorative processes, plays an important role in memory transfer from its temporary store in the hippocampus to the more permanent storage in the neocortex. Alzheimer’s disease (AD) affects memory and sleep. The aim of this study was to explore disturbances in global and local synchrony patterns between brain regions in the APP/PS1 mouse model of the AD during natural sleep. We used 8 male APPswe/PS1dE9 mice and 6 wild-type littermates, aged 5–6 months, with multiple electrode bundles implanted into cortical regions, thalamus and hippocampus. We measured video-EEG in freely moving animals and analyzed synchrony during NREM vs REM sleep. Global synchrony between medial frontal cortex and hippocampus measured with magnitude-squared coherence was slightly decreased in delta range during NREM stage of sleep in APP/PS1 mice. In contrast, local hippocampal synchrony measured with cross-frequency coupling remained intact. Ripple structure or frequency did not differ between the genotypes. However, the coupling of the spindle-band power peak in the medial prefrontal cortex to hippocampal ripples was significantly decreased compared to wild-type animals. The delicate timing of hippocampal ripples, frontal delta, and corticothalamic spindle oscillations may be the first sign of impaired memory in amyloid plaque-forming transgenic mice.
Near-infrared tunable metalens based on phase change material Ge2Sb2Te5
Authors: Bai Wei , Yang Ping , Huang Jie , Chen Dingbo , Zhang Jingjing , Zhang Zhaojian , Yang Junbo , Xu Bing
Published: March 2019

Metasurfaces draw everyone’s attention because they can precisely control the phase, amplitude and polarization of emergent light to achieve light field control in recent years. As one of the most practicable devices among the many applications of metasurface, metalens can extremely reduce the size as well as complexity of optical systems and realizes the higher optical quality compared with conventional lens. So it will be very potential to use metalens in integration systems to reaching higher integration and efficiency. In addition, dynamic control is always desirable in optical systems. In this work, we firstly design a near-infrared tunable metalens treating phase change materials as the meta-atoms which makes the tunable metalens become more compact. At designed wavelength of 1.55 μm, the focusing efficiency of our amorphous metalens is more than 16 times of the efficiency when it works at crystalline state, and its focal length can stay almost unchanged when the GST state is switched. The broadband performance of the metalens is also confirmed. This work may bring some good opportunities for the revolution of the next generation tunable integrated optics.
Transcriptomic analysis of the prothoracic gland from two lepidopteran insects, domesticated silkmoth Bombyx mori and wild silkmoth Antheraea pernyi
Authors: Bian Hai-Xu , Chen Dong-Bin , Zheng Xi-Xi , Ma Hong-Fang , Li Yu-Ping , Li Qun , Xia Run-Xi , Wang Huan , Jiang Yi-Ren , Liu Yan-Qun , Qin Li
Published: March 2019

The prothoracic gland (PG) is an important endocrine organ of synthesis and secretion of ecdysteroids that play critical roles in insects. Here, we used a comparative transcriptomic approach to characterize some common features of PGs from two lepidopteran speciesBombyx moriandAntheraea pernyi. Functional and pathway annotations revealed an overall similarity in gene profile between the two PG transcriptomes. As expected, almost all steroid hormone biosynthesis genes and the prothoracicitropic hormone receptor gene (Torso) were well represented in the two PGs. Impressively, two ecdysone receptor genes, eleven juvenile hormone related genes, more than 10 chemosensory protein genes, and a set of genes involved in circadian clock were also presented in the two PGs. Quantitative real time -PCR (qRT-PCR) validated the expression of 8 juvenile hormone and 12 clock related genes inB. moriPG, and revealed a different expression pattern during development in whole fifth larval instar. This contribution to insect PG transcriptome data will extend our understanding of the function and regulation of this important organ.
Quantitative relationships between SMAD dynamics and target gene activation kinetics in single live cells
Authors: Tidin Onur , Friman Elias T. , Naef Felix , Suter David M.
Published: March 2019

The transduction of extracellular signals through signaling pathways that culminate in a transcriptional response is central to many biological processes. However, quantitative relationships between activities of signaling pathway components and transcriptional output of target genes remain poorly explored. Here we developed a dual bioluminescence imaging strategy allowing simultaneous monitoring of nuclear translocation of the SMAD4 and SMAD2 transcriptional activators upon TGF-β stimulation, and the transcriptional response of the endogenous connective tissue growth factor (ctgf) gene. Using cell lines allowing to vary exogenous SMAD4/2 expression levels, we performed quantitative measurements of the temporal profiles of SMAD4/2 translocation and ctgf transcription kinetics in hundreds of individual cells at high temporal resolution. We found that while nuclear translocation efficiency had little impact on initial ctgf transcriptional activation, high total cellular SMAD4 but not SMAD2 levels increased the probability of cells to exhibit a sustained ctgf transcriptional response. The approach we present here allows time-resolved single cell quantification of transcription factor dynamics and transcriptional responses and thereby sheds light on the quantitative relationship between SMADs and target gene responses.
High Incidence of a Novel Rickettsia Genotype in Parasitic Haemaphysalis longicornis from China-North Korea Border
Authors: Xu Heling , Zhang Qi , Guan Hao , Zhong Yuening , Jiang Fenghua , Chen Zeliang , Han Xiaohu
Published: March 2019

Ticks are notorious vectors for various pathogens that cause infections in animals and humans worldwide. Rickettsia spp., a zoonotic tick-borne pathogen that could be used as a weapon agent, is widely spread in China. In the present study, ticks were collected for species identification and Rickettsia screening. PCR amplification targeting the tick 18s rRNA gene was first conducted for species validation, and then, amplification was conducted for the Rickettsia housekeeping gene for the infection rate and phylogenetic analysis. The collected ticks were identified as Haemaphysalis longicornis, 7.36% of which were Rickettsia-positive. The phylogenetic analysis showed that the Rickettsia in the parasitic ticks belonged to a novel genotype, whose closest genetic relationship was with Rickettsia heilongjiangenesis. The samples were collected in Dandong, a city on the border between China and North Korea. Considering the geographical and biological situations of the sampling sites, more extensive surveillance and risk evaluation of the tick species and tick-borne diseases are required.
Robust mouse tracking in complex environments using neural networks
Authors: Geuther Brian Q. , Deats Sean P. , Fox Kai J. , Murray Steve A. , Braun Robert E. , White Jacqueline K. , Chesler Elissa J. , Lutz Cathleen M. , Kumar Vivek
Published: March 2019

The ability to track animals accurately is critical for behavioral experiments. For video-based assays, this is often accomplished by manipulating environmental conditions to increase contrast between the animal and the background in order to achieve proper foreground/background detection (segmentation). Modifying environmental conditions for experimental scalability opposes ethological relevance. The biobehavioral research community needs methods to monitor behaviors over long periods of time, under dynamic environmental conditions, and in animals that are genetically and behaviorally heterogeneous. To address this need, we applied a state-of-the-art neural network-based tracker for single mice. We compare three different neural network architectures across visually diverse mice and different environmental conditions. We find that an encoder-decoder segmentation neural network achieves high accuracy and speed with minimal training data. Furthermore, we provide a labeling interface, labeled training data, tuned hyperparameters, and a pretrained network for the behavior and neuroscience communities.
Allosteric effects in cyclophilin mutants may be explained by changes in nano-microsecond time scale motions
Authors: Wapeesittipan Pattama , Mey Antonia S. J. S. , Walkinshaw Malcolm D. , Michel Julien
Published: March 2019

This work investigates the connection between stochastic protein dynamics and function for the enzyme cyclophilin A (CypA) in wild-type form, and three variants that feature several mutations distal from the active site. Previous biophysical studies have suggested that conformational exchange between a ‘major’ active and a ‘minor’ inactive state on millisecond timescales plays a key role in catalysis for CypA. Here this hypothesis is addressed by a variety of molecular dynamics simulation techniques. Strikingly we show that exchange between major and minor active site conformations occurs at a rate that is 5 to 6 orders of magnitude faster than previously proposed. The minor active site conformation is found to be catalytically impaired, and decreased catalytic activity of the mutants is caused by changes in Phe113 motions on a ns-μs timescale. Therefore millisecond timescale motions may not be necessary to explain allosteric effects in cyclophilins.
Defect engineering in earth-abundant electrocatalysts for CO2 and N2 reduction
Authors: Wang Qichen , Lei Yongpeng , Wang Dingsheng , Li Yadong
Published: March 2019

The electrocatalytic CO2 reduction reaction (CRR) and N2 reduction reaction (NRR), which convert inert small molecules into high-value products under mild conditions, have received much research attention.
Novel one step preparation of a 3D alginate based MOF hydrogel for water treatment
Authors: Zhuang Yuan , Kong Yan , Wang Xuechun , Shi Baoyou
Published: March 2019

We propose a novel one-step method for the preparation of a novel 3D alginate based MOF hydrogel and use it for tetracycline removal.
Photocuring of 4-arm coumarin-functionalised monomers to form highly photoreversible crosslinked epoxy coatings
Authors: Hughes T. , Simon G. P. , Saito K.
Published: March 2019

Highly photoreversible photocurable crosslinked epoxy coatings that can heal substantial surface damage were formed by the synthesis of unique monomers.
Adverse effects of post-heat treatment on the interfacial bonding strength of direct laser deposition Inconel 625/1045 composites
Authors: Zhou Chen , Jin Ding , Zhang Qiaoxin , Yu Jingui
Published: March 2019

Adverse effects of post-heat treatment on interfacial bonding strength of DLD composites probed by fractography and metallographic analysis.
Room-temperature synthesized SnO2 electron transport layers for efficient perovskite solar cells
Authors: Shi Shengwei , Li Jing , Bu Tongle , Yang Shili , Xiao Junyan , Peng Yong , Li Wei , Zhong Jie , Ku Zhiliang , Cheng Yi-Bing , Huang Fuzhi
Published: March 2019

Room-temperature processed SnO2 as electron transport layer materials for efficient flexible perovskite solar cells.
Manganese ion pre-intercalated hydrated vanadium oxide as a high-performance cathode for magnesium ion batteries
Authors: Deng Xuanwei , Xu Yanan , An Qinyou , Xiong Fangyu , Tan Shuangshuang , Wu Liming , Mai Liqiang
Published: March 2019

The development of rechargeable magnesium ion batteries (MIBs) has received increasing attention due to its low cost, high theoretical volumetric capacities, environmental friendliness and good safety.
Development of a selective reaction-based turn-on fluorosensor and biomarker for hypochlorite ions in aqueous media
Authors: Ahmmed Ejaj , Lohar Somenath , Ghatak Sumanta , Hira Sumit Kumar , Manna Partha Pratim , Chattopadhyay Pabitra
Published: March 2019

A new structurally characterised non-fluorescent non-cytotoxic probe (LH) selectively senses trace level hypochlorite ions in aqueous medium at pH 7.4 by turn-on ICT based fluorescence through thioacetyl cleavage applicable in bioimaging.
Multifunctional two dimensional Bi2Se3 nanodiscs for combined antibacterial and anti-inflammatory therapy for bacterial infections
Authors: Ouyang Jiang , Wen Mei , Chen Wansong , Tan Yanni , Liu Zhenjun , Xu Qunfang , Zeng Ke , Deng Liu , Liu You-Nian
Published: March 2019

A multifunctional platform based on two-dimensional Bi2Se3 nanodiscs for combined antibacterial and anti-inflammatory therapy is developed.
Photoswitchable polymerization catalysis: state of the art, challenges, and perspectives
Authors: Ihrig Svante P. , Eisenreich Fabian , Hecht Stefan
Published: March 2019

Adjusting the length, composition, and microstructure of a polymer during the process of its formation in principle allows achieving the desired properties, thereby enabling custom-design of the thus generated polymer for its targeted function.
Development of biomineralization-inspired hybrids based on β-chitin and zinc hydroxide carbonate and their conversion into zinc oxide thin films
Authors: Kuo David , Kajiyama Satoshi , Kato Takashi
Published: March 2019

Hybrid thin films based on an environmentally friendly biopolymer, β-chitin and zinc hydroxide carbonate were developed through a biomineralization-inspired approach.
A generalized van der Waals model for light gas adsorption prediction in IRMOFs
Authors: Kong Lingli , Adidharma Hertanto
Published: March 2019

A generalized van der Waals model for predicting the adsorption isotherms in IRMOFs by defining different attractive regions.
The structural, phonon and optical properties of [CH3NH3]M0.5CrxAl0.5−x(HCOO)3 (M = Na, K; x = 0, 0.025, 0.5) metal–organic framework perovskites for luminescence thermometry
Authors: Ptak Maciej , Dziuk Błażej , Stefańska Dagmara , Hermanowicz Krzysztof
Published: March 2019

We report the structural, phonon and optical properties of perovskite-type heterometallic formates templated by methylammonium cations.
The chemical composition of a cold-pressed milk thistle seed flour extract, and its potential health beneficial properties
Authors: Choe Uyory , Li Yanfang , Gao Boyan , Yu Lu , Wang Thomas T. Y. , Sun Jianghao , Chen Pei , Yu Liangli (Lucy)
Published: March 2019

The chemical composition of a milk thistle seed flour extract and its potential health-promoting properties.
Methyl-triflate-mediated dearylmethylation of N-(arylmethyl)carboxamides via the retro-Mannich reaction induced by electrophilic dearomatization/rearomatization in an aqueous medium at room temperature
Authors: Peng Hui , Ma Jinhui , Luo Wenkun , Zhang Guangwen , Yin Biaolin
Published: March 2019

Dearylmethylation of N-(arylmethyl)carboxamides was achieved under metal-free conditions in an aqueous medium induced by electrophilic dearomatization/rearomatization.
Repairing the N-vacancy in an InN monolayer using NO molecules: a first-principles study
Authors: Cui Hao , Chen Dachang , Yan Chao , Zhang Ying , Zhang Xiaoxing
Published: March 2019

The synthesis of a perfect InN monolayer is important to achieve desirable properties for the further investigation and application of InN monolayers.
Understanding the good and poor cell targeting activity of gold nanostructures functionalized with molecular units for the epidermal growth factor receptor
Authors: Mazzuca Claudia , Di Napoli Benedetta , Biscaglia Francesca , Ripani Giorgio , Rajendran Senthilkumar , Braga Andrea , Benna Clara , Mocellin Simone , Gobbo Marina , Meneghetti Moreno , Palleschi Antonio
Published: March 2019

The key role of polyethylene glycol is demonstrated.
A novel strategy to boost the oxygen evolution reaction activity of NiFe-LDHs with in situ synthesized 3D porous reduced graphene oxide matrix as both the substrate and electronic carrier
Authors: Gu Yanfang , Wang Yuanqiang , An Wei , Men Yong , Rui Yichuan , Fan Xinyi , Li Bin
Published: March 2019

NiFe-LDHs anchored on a 3D rGO matrix achieved a small overpotential and a relatively stable operating potential.
A highly selective and light-up red emissive fluorescent probe for imaging of penicillin G amidase inBacillus cereus
Authors: Wang Jianguo , Chen Qingqing , Wu Jie , Zhu Wenping , Wu Yongquan , Fan Xiaolin , Zhang Guanxin , Li Yibao , Jiang Guoyu
Published: March 2019

A highly selective and red-emissive fluorescent probe (HCyNB) for penicillin G amidase (PGA) has been prepared and used for imaging of endogenousPGAin penicillinase-producingBacillus subtilis.
Natural cholinesterase inhibitors from marine organisms
Authors: Moodie Lindon W. K. , Sepčić Kristina , Turk Tom , Frangež Robert , Svenson Johan
Published: March 2019

This review provides a critical and comprehensive survey of marine cholinesterase inhibitors.
Tracking sodium migration in TiS2usingin situTEM
Authors: Han Bo , Chen Shulin , Zou Jian , Shao Ruiwen , Dou Zhipeng , Yang Chen , Ma Xiumei , Lu Jing , Liu Kaihui , Yu Dapeng , Wang Liping , Wang Haicheng , Gao Peng
Published: March 2019

Usingin situTEM, the structural evolution and migration dynamics are revealed during sodium migration in TiS2.
Assisting anti-PD-1 antibody treatment with a liposomal system capable of recruiting immune cells
Authors: Zhou Boyang , Jiang Qiongchao , Xiao Xiaoyun , Xu Xiaolin , Xu Yanni , Kong Yao , Zhang Wenyue , Zeng Yunting , Liu Xiaodi , Luo Baoming
Published: March 2019

Less than 30% of patients exhibit durable therapeutic responses to anti-PD-1 antibodies. A liposomal system was synthesized to assist anti-PD-1 treatment.
Online fabrication of ultralight, three-dimensional, and structurally stable ultrafine fibre assemblies with a double-porous feature
Authors: Chen Xin , Xu Yang , Zhang Wenxin , Xu Kangli , Ke Qinfei , Jin Xiangyu , Huang Chen
Published: March 2019

Three-dimensional, ultralight fibre assemblies are constructed via a double-porous structure containing both macropores and nanopores.
Scandium-catalyzed electrophilic alkene difunctionalization: regioselective synthesis of thiosulfone derivatives
Authors: Huang Shuai , Li Haoyu , Xie Tian , Wei Fang , Tung Chen-Ho , Xu Zhenghu
Published: March 2019

A scandium(iii)-catalyzed electrophilic alkene difunctionalization reaction with the synergistic formation of two C–S bonds has been developed. This reaction features a broad substrate scope, simple procedures, 100% atom economy, and a reversed regioselectivity compared to previously studied alkene sulfonylation methods.
Synergistic use of NMR computation and quantitative interproton distance analysis in the structural determination of neokadcoccitane A, a rearranged triterpenoid featuring an aromatic ring D from Kadsura coccinea
Authors: Xu Hou-Chao , Hu Kun , Shi Xiao-Huo , Tang Jian-Wei , Li Xiao-Nian , Sun Han-Dong , Puno Pema-Tenzin
Published: March 2019

A novel lanostane triterpenoid possessing an aromatic ring D, along with two novel norlanostane triterpenoids, were isolated from Kadsura coccinea.
Silver-mediated synthesis of novel 3-CF3/CN/phosphonate-substituted pyrazoles as pyrrolomycin analogues from 3-formylchromones and diazo compounds
Authors: Peng Xiaofeng , Zhang Xiaofei , Li Shunyao , Lu Yunfu , Lan Lefu , Yang Chunhao
Published: March 2019

Herein, a simple and regioselective synthesis of (2-hydroxyphenyl)(3-(trifluoromethyl/cyano/phosphonate)-1H-pyrazol-5-yl)methanones as pyrrolomycin analogues was reported.
New chemical mechanism explaining the breakdown of protective oxides on high temperature steels in biomass combustion and gasification plants
Authors: Blomberg Tom , Tripathi Tripurari , Karppinen Maarit
Published: March 2019

New chemical mechanism explaining the breakdown of protective Cr2O3on high temperature steels under KCl containing deposits in biomass combustion.
Poly(norepinephrine)-coated FeOOH nanoparticles as carriers of artemisinin for cancer photothermal-chemical combination therapy
Authors: He Zi , Su Huiling , Shen Yuqing , Shi Wei , Liu Xin , Liu Yang , Zhang Fuhui , Zhang Yansheng , Sun Yanan , Ge Dongtao
Published: March 2019

Tumor-specific FeOOH@PNE-Art nanoparticles were fabricated that showed high efficacy of photothermal-chemical combination therapy and low toxicity to normal tissue.
Step-freeze-drying method for carbon aerogels: a study of the effects on microstructure and mechanical property
Authors: Hu Lei , He Rujie , Lu Zhang , Zhang Keqiang , Bai Xuejian
Published: March 2019

In this paper, a novel step-freeze-drying method was used to prepare carbon aerogels.
Enzyme immobilized millimeter-sized polyHIPE beads with easy separability and recyclability
Authors: Wang Mengjie , Wang Meng , Zhu Yun , Zhang Shengmiao , Chen Jianding
Published: March 2019

Enzyme immobilized reusable millimeter-sized beads were prepared through covalently immobilizing Candida antarctica lipase B onto emulsion-templated porous beads.
Development of an automated kinetic profiling system with online HPLC for reaction optimization
Authors: Christensen Melodie , Adedeji Folarin , Grosser Shane , Zawatzky Kerstin , Ji Yining , Liu Jinchu , Jurica Jon A. , Naber John R. , Hein Jason E.
Published: March 2019

Application of an automated profiling system with online HPLC uncovers an induction period in a cross-coupling and facilitates catalyst optimization.
Flow and clogging of particles in shaking random obstacles
Authors: Ai Bao-quan , Meng Fan-hua , He Yu-ling , Zhang Xiao-miao
Published: March 2019

Transport of three types of particles (passive particles, active particles, and polar particles) is investigated in a random obstacle array in the presence of a dc drift force.
Macroporous three-dimensional MXene architectures for highly efficient solar steam generation
Authors: Zhao Xing , Zha Xiang-Jun , Pu Jun-Hong , Bai Lu , Bao Rui-Ying , Liu Zheng-Ying , Yang Ming-Bo , Yang Wei
Published: March 2019

3D MXene architectures combining the high light absorption ability of MXenes and porous melamine foam exhibit efficient solar steam generation.
Adapting to extreme environments: can coral reefs adapt to climate change?
Authors: Crabbe M. James C.
Published: March 2019

Reef-building corals throughout the world have an annual value of tens of billions of dollars, yet they are being degraded at an increasing rate by many anthropogenic and environmental factors. Despite this, some reefs show resilience to such extreme environmental changes. This review shows how techniques in computational modelling, genetics, and transcriptomics are being used to unravel the complexity of coral reef ecosystems, to try and understand if they can adapt to new and extreme environments. Considering the ambitious climate targets of the Paris Agreement to limit global warming to 2°C, with aspirations of even 1.5°C, questions arise on how to achieve this. Geoengineering may be necessary if other avenues fail, although global governance issues need to play a key role. Development of large and effective coral refugia and marine protected areas is necessary if we are not to lose this vital resource for us all.
Device for the assessment of occupational exposure to time‐varying magnetic field due to movement in magnetic resonance environments
Authors: Hartwig V. , Ferrante Vero L.F. , Virgili G. , Landini L. , Giovannetti G.
Published: March 2019

Also according to the recent Directive by the European Parliament and the Council of the European Union, there is a need for a simple but reliable device to measure exposure to the magnetic field (MF) of magnetic resonance (MR) workers, especially given the continuing development of scanner using a higher static MF. Here the authors describe a novel device for assessing personal exposure to the MF. The time recording system can measure the static MF value at which the operator is exposed to and the field gradients due to his/her movements in the MR environment. The device does not require any cable for data management and transmission and it is able to record the instantaneous and cumulative exposition dose. The device can be used in all MR environments, for clinical or industrial applications.
Modelling and optimisation algorithm for length‐matching escape routing of differential pairs
Authors: Li Tai‐Hung , Chen Jwu‐E , Chen Tai‐Chen , Jimmy Liu Chien‐Nan
Published: March 2019

To improve the performance and signal integrity for printed circuit board designs, considering differential pairs in the escape routing is an important issue. Previous works use two‐stage approaches, meeting points determining followed by differential pairs connecting, to generate a routing solution. However, existing approaches may produce either non‐length‐matching solutions or longer length‐matching solutions. In this Letter, the authors propose an escape routing model with one‐stage optimisation to simultaneously determine median points and route length‐matching paths for all differential pairs. Experimental results show that their approach can significantly reduce maximum and average differential‐pair skews with 100% length‐matching results.
Design and direct field current control scheme of a synchronous generator with PM exciter based on the reference frequency
Authors: Lee Dong‐Hee
Published: March 2019

This study presents the design and control scheme of a self‐excited 10 kW–380 V synchronous generator using a permanent magnet (PM) exciter. The PM exciter generates field current according to the engine speed to maintain the output voltage of the proposed generator so that constant voltage can be produced regardless of the speed. For the direct control the field winding current, a current controller is designed and embedded on the shaft. In the proposed generator, the reference current is determined by an external voltage controller and it is transferred to the rotating embedded current controller using an infrared (IR) transmitter and receiver aligned to the shaft. In order to improve control performance, the reference field current is controlled by the actual frequency of the generator based on the reference frequency. Therefore, when the engine speed is fluctuating due to engine governor dynamics, the frequency‐based field current can maintain the output voltage constant because of the compensation term for speed variations. In the compared experimental results between the conventional generator with winding type exciter and the proposed generator system, both dynamic performance and operating efficiency of the proposed system are improved.
Miniaturised antenna at a sub‐GHZ band for industrial remote controllers
Authors: Yilmaz Vadi Su , Bilgin Gulsima , Aydin Elif , Kara Ali
Published: March 2019

This study presents the design and the fabrication of a miniaturised sub‐GHz antenna for remote control applications. Miniaturisation techniques were examined to identify the most appropriate topology for sub‐GHz band requirements. First, the design parameters of the antenna were determined, and then, a commercial electromagnetic simulation tool was used for the design and optimisation phases. Then, measurements of the fabricated antenna were undertaken. Parametric studies with several iterations were performed to achieve the best possible results. Second, the effects of the box in which the antenna could be placed were examined as most of such antennas are enclosed by plastic boxes. For this purpose, material properties of a typical industrial box available in the market were studied initially, and the most appropriate material of the box was used in simulations. Finally, a polyamide box with appropriate size was fabricated, and the designed antenna was placed inside the box and the measurements were conducted. The measurement results show that the designed antenna provides resonance at the targeted license‐free band with adequate size for industrial remote controllers.
On end‐fire super directivity of arrays of two elementary dipoles and isotropic radiators
Authors: Hazdra Pavel , Kracek Jan , Lonsky Tomas
Published: March 2019

The concept of source currents of a radiating source can be employed to express its directivity in some particular cases analytically. For an antenna array, this concept can be extended to the concept of a generalised directivity based on self‐ and mutual radiation intensities, self‐ and mutual radiated powers and excitation currents of array elements. These approaches were applied to examples of the array of two elementary dipoles and the array of two isotropic radiators. Particularly, the evaluation of the directivity of the end‐fire arrays, which are of special attention due to superdirective properties, was treated. Novel closed‐form expressions for the directivity of these arrays with out‐of‐phase excitation were derived. It was observed that the end‐fire directivity can be further enhanced by optimising the excitation currents of the arrays. Their optimal phase difference and corresponding increased directivity were also found analytically. The results were validated by a full‐wave simulator.
Exponential Capillary Pressure Functions in Sedimentary Rocks
Authors: Afrough Armin , Bahari Moghaddam Mehdi , Romero-Zerón Laura , Balcom Bruce J.
Published: March 2019

The Brooks-Corey power-law capillary pressure model is commonly imposed on core analysis data without verifying the validity of its underlying assumptions. The Brooks-Corey model, originally developed to model the pressure head during the drainage of soil, is only valid at low wetting phase saturations. However, such models are often applied in petroleum production simulations and may lead to erroneous recovery factors when the saturation range of interest is far from the end points. We demonstrate that exponential models work much better for capillary pressure compared to the Brooks-Corey model over a wide saturation range. Mercury injection porosimetry, petrographic image analysis, and magnetic resonance studies suggest that the pore and throat size distribution in many rocks are log-normally distributed. This fact was previously employed to calculate the capillary pressure function as a function of saturation for pore size distributions described by atruncated log-normal distribution. Employing a Taylor series expansion, we simplify the random fractal capillary pressure model of Hunt toPc= exp(a−bS), whereSis the wetting phase saturation, andaandbcharacteristic of the porous medium. An extensive dataset of seventeen centrifuge capillary pressure measurements were used in this research to demonstrate the merit of the new method. For both sandstones and carbonates, the logarithm of capillary pressure showed a linear relationship with saturation as observed by magnetic resonance imaging centrifuge capillary pressure measurements over a wide saturation range. This work demonstrates that: (a) in semi-log plots of capillary pressure as a function of saturation, capillary pressurewill vary linearly over a wide saturation range, (b) such a plot as described in (a) will show the uni-or bimodal pore size distribution of the rock, (c) the exponential capillary pressure function simpliﬁes analytical modelsthat use the capillary pressure function, for example oil recovery models for fractured reservoirs.
The nonconforming Virtual Element Method for eigenvalue problems
Authors: Gardini Francesca , Manzini Gianmarco , Vacca Giuseppe
Published: March 2019

We analyse the nonconforming Virtual Element Method (VEM) for the approximation of elliptic eigenvalue problems. The nonconforming VEM allows to treat in the same formulation the two- and three-dimensional case. We present two possible formulations of the discrete problem, derived respectively by the nonstabilized and stabilized approximation of theL2-inner product, and we study the convergence properties of the corresponding discrete eigenvalue problem. The proposed schemes provide a correct approximation of the spectrum, in particular we prove optimal-order error estimates for the eigenfunctions and the usual double order of convergence of the eigenvalues. Finally we show a large set of numerical tests supporting the theoretical results, including a comparison with the conforming Virtual Element choice.
Digitale Medizin in der Onkologie: Clinical Decision Support, Real World Data und Patient Involvement
Authors: Wagner Sebastian , Serve Hubert
Published: March 2019

Was ist neu?

Stand der Dinge In der Onkologie kam es zuletzt zu einem rasanten Wissenszuwachs. Neue Entwicklungen in Diagnostik und Therapie von Tumorerkrankungen haben die Grundlagen für individualisierte Therapiekonzepte geschaffen. Aktuell werden innovative Onkologie-spezifische IT-Lösungen entwickelt mit dem Ziel, die Heilungschancen für Patienten mit Tumorerkrankungen langfristig zu verbessern.

Clinical Decision Support Die Komplexität onkologischer Therapieentscheidungen hat durch Einführung neuer Biomarker und zielgerichteter Therapeutika stark zugenommen. Erste „intelligente“ Systeme, die aktiv Therapieoptionen auf Basis von vorhandenen Daten vorschlagen, sind verfügbar, aber noch nicht weit verbreitet und unzureichend klinisch validiert.

Real-World Data und Real-World Evidence Durch die zunehmende Verbreitung von elektronischen Gesundheitsakten wird eine strukturierte Sammlung und Auswertung von Daten aus der onkologischen Routineversorgung möglich. Real World Data werden eingesetzt, um die Sicherheit und Nebenwirkungen von onkologischen Medikamenten zu überwachen und können helfen, onkologische Therapieleitlinien zu entwickeln.

Patient Involvement und Patient Reported Outcomes Die frühe Meldung von Symptomen und Nebenwirkungen (Patient Reported Outcomes) verspricht eine verbesserte Behandlung und eine gesteigerte Therapieadhärenz. Patient Reported Outcomes können auch im Rahmen von klinischen Studien und zur Qualitätssicherung eingesetzt werden. Erste Studien zeigen, dass eine IT-gestützte Erfassung von Patient Reported Outcomes Symptome und Überleben von Patienten mit Tumorerkrankungen positiv beeinflussen kann.
Intramurales Hämatom der Aorta: eine diagnostische Herausforderung
Authors: Haring Bernhard , Kickuth Ralph , Fluck Friederika
Published: March 2019

Anamnese und klinischer Befund Eine 75-jährige Patientin wurde wegen akuter Übelkeit, Völlegefühl, Erbrechen ohne Blutbeimengung und unspezifischer abdomineller Schmerzsymptomatik nächtlich aufgenommen. In der Anamnese fand sich neben einem Vorhofflimmern, weswegen sie vollantikoaguliert war, ein Z. n. Schrittmacheranlage sowie eine diastolische Herzinsuffizienz.

Untersuchungen und Diagnose Im Röntgenbild des Thorax fiel eine die Kalkspange des Aortenbogens umgebende Transparenzminderung auf. Eine CT-Angiografie erbrachte den Nachweis eines intramuralen Hämatoms (IMH) der Aorta vom Abgang der A. subclavia links bis nach abdominell zum Abgang der A. mesenterica inferior mit fokalen Ulzerationen.

Therapie und Verlauf Da sich das IMH auf die Aorta descendens beschränkte, wurde zunächst ein konservatives Vorgehen mit blutdrucksenkenden Maßnahmen gewählt. Die Beschwerdesymptomatik der Patientin verbesserte sich trotz medikamentöser Therapie nicht. Aufgrund des komplizierten Verlaufs wurde nach interdisziplinärer Fallbesprechung eine transfemorale endovaskuläre Reparatur der Aorta mittels Stentgraft-Prothese durchgeführt. Postinterventionell erholte sich die Patientin gut von dem Eingriff, war beschwerdefrei und konnte entlassen werden.

Folgerung Entscheidend für das Management eines IMH ist eine zeitnahe Diagnose und die korrekte Klassifizierung der Ausdehnung (Typ Stanford A oder Stanford B). Während für ein IMH Typ Stanford A die Indikation zur chirurgischen Versorgung gegeben ist, ist bei Typ Stanford B eine interdisziplinäre Falldiskussion sinnvoll. Bei Vorliegen eines unkomplizierten IMH ist ein konservatives Prozedere mit adäquater Einstellung einer arteriellen Hypertonie empfohlen. Bei komplizierten Verläufen sollte die endovaskuläre Therapie (Thoracic Endovascular Repair/TEVAR) als Versorgungsmöglichkeit erwogen werden.
Update on Imaging of Knee Arthroplasties: Normal Findings and Hardware Complications
Authors: Mar Winnie , Tan Isaiah , Song Albert , Omar Imran , Taljanovic Mihra , Stacy Gregory
Published: March 2019

Total knee arthroplasty (TKA) is the most common joint replacement performed. This article reviews the normal appearance of TKA including the most common types of arthroplasties as well as complications. Common complications at the present time are infection, aseptic loosening, and instability. Rarer complications such as polyethylene wear, periprosthetic fracture, and soft tissue pathology are also discussed. Although the mainstay of imaging is radiographs, newer techniques in TKA imaging such as computed tomography and magnetic resonance imaging are also reviewed.
Current and Future Treatments in Alzheimer's Disease
Authors: Atri Alireza
Published: March 2019

The foundation of current Alzheimer's disease (AD) treatment involves pharmacological and nonpharmacological management and care planning predicated on patient-centered psychoeducation, shared goal-setting, and decision-making forged by a strong triadic relationship between clinician and the patient-caregiver dyad. Food and Drug Administration (FDA) approved AD medications, cholinesterase-inhibitors (ChEIs), and the N-methyl-d-aspartate (NMDA) antagonist memantine, when utilized as part of a comprehensive care plan, while generally considered symptomatic medications, can provide modest “disease course-modifying” effects by enhancing cognition, and reducing loss of independence. When combined, pharmacologic and nonpharmacologic treatments can meaningfully mitigate symptoms and reduce clinical progression and care burden. AD pharmacotherapy first involves identification and elimination of potentially harmful medications and supplements. First line treatment for neuropsychiatric symptoms and problem behaviors is nonpharmacological and involves psychoeducation, trigger identification, and implementation, iterative evaluation, and adjustment of behavioral and environmental interventions. Intensive research efforts are underway to develop more accurate and practical AD diagnostic biomarkers and clinical tools and better therapeutics. Ongoing research studies for primary and secondary prevention of AD and clinical trials evaluating symptomatic and disease-modifying treatments in symptomatic AD are directed at diverse therapeutic targets including neurochemicals, amyloid and tau pathological processes, mitochondria, inflammatory pathways, neuroglia, and multimodal lifestyle interventions.
IR Residency Training: Is It Appropriate for the Private Practice IR?
Authors: Marx M.
Published: March 2019

Interventional radiology (IR) training programs have undergone many changes in the recent past. These changes largely revolve around making programs more “clinical” in nature by requiring each program to have a formal consult service, outpatient clinics, and admitting privileges. Instituting these changes has been challenging, but the programs are up and running. As a testament to the success of these changes, IR has now become one of the very most competitive residencies to enter. This article provides insights into the process of change within the IR training paradigm, and describes the personal experience of one of the architects of the new training programs.
Motions of water and solutes—Slaving versus plasticization phenomena
Authors: Combarro Palacios Izaskun , Olsson Christoffer , Kamma-Lorger Christina S. , Swenson Jan , Cerveny Silvina
Published: March 2019

It is well-accepted that hydration water is crucial for the structure, dynamics, and function of proteins. However, the exact role of water for the motions and functions of proteins is still debated. Experiments have shown that protein and water dynamics are strongly coupled but with water motions occurring on a considerably faster time scale (the so-called slaving behavior). On the other hand, water also reduces the conformational entropy of proteins and thereby acts as a plasticizer of them. In this work, we analyze the dynamics (using broadband dielectric spectroscopy) of some specific non-biological water solutions in a broad concentration range to elucidate the role of water in the dynamics of the solutes. Our results demonstrate that at low water concentrations (less than 5 wt. %), the plasticization phenomenon prevails for all the materials analyzed. However, at higher water concentrations, two different scenarios can be observed: the slaving phenomenon or plasticization, depending on the solute analyzed. These results generalize the slaving phenomenon to some, but not all, non-biological solutions and allow us to analyze the key factors for observing the slaving behavior in protein solutions as well as to reshaping the slaving concept.
Modeling optical coupling of plasmons and inhomogeneously broadened emitters
Authors: Purcell Thomas A. R. , Sukharev Maxim , Seideman Tamar
Published: March 2019

Optically coupling quantum emitters to nanoparticles provides the foundation for many plasmonic applications. Including quantum mechanical effects within the calculations can be crucial for designing new devices, but classical approximations are sometimes sufficient. Comprehending how the classical and quantum mechanical descriptions of quantum emitters alter their calculated optical response will lead to a better understanding of how to design devices. Here, we describe how the semiclassical Maxwell-Liouville method can be used to calculate the optical response from inhomogeneously broadened states. After describing the Maxwell-Liouville algorithm, we use the method to study the photon echoes from quantum dots and compare the results against analytical models. We then modify the quantum dot’s state distribution to match a PbS 850 nm quantum dot’s absorption spectra to see how the complete quasi-band structure affects their coupling to gold nanoislands. Finally, we compare the results with previously published work to demonstrate where the complete quantum dot description is necessary.
Investigation of etching optimization in capacitively coupled SF6–O2 plasma
Authors: Alshaltami Khaled Ali , Daniels Stephen
Published: March 2019

The selective etching process is widely used for achieving the desired etch rate in semiconductor fabrication. Parameters such as input power, operating pressure, gas mixture, chamber geometry, and amplitude of the radio-frequency voltage govern the etch rate and etch quality in plasma. In this work, we experimentally investigated the optimum plasma etching conditions required to achieve an anisotropic etch profile and analyzed how the optimum etching can be carried out using an appropriate operating pressure and oxygen concentration. Optical emission spectroscopy was used to measure the concentrations of oxygen and fluorine, and Langmuir probe was used to measure the electron density in the plasma. The oxygen concentration was varied from zero to 100 vol. % for pressures in the range of 20–600 mTorr. The optimum etch conditions are used to study the ion energy distribution given by Kawamura et al., Plasma Sources Sci. Technol. 8, R45 (1999). The results suggest that in addition to O2% and pressure, the DC bias is another crucial parameter for achieving the optimum etch conditions.
Improving collective variables: The case of crystallization
Authors: Zhang Yue-Yu , Niu Haiyang , Piccini GiovanniMaria , Mendels Dan , Parrinello Michele
Published: March 2019

Several enhanced sampling methods, such as umbrella sampling or metadynamics, rely on the identification of an appropriate set of collective variables. Recently two methods have been proposed to alleviate the task of determining efficient collective variables. One is based on linear discriminant analysis; the other is based on a variational approach to conformational dynamics and uses time-lagged independent component analysis. In this paper, we compare the performance of these two approaches in the study of the homogeneous crystallization of two simple metals. We focus on Na and Al and search for the most efficient collective variables that can be expressed as a linear combination of X-ray diffraction peak intensities. We find that the performances of the two methods are very similar. Wherever the different metastable states are well-separated, the method based on linear discriminant analysis, based on its harmonic version, is to be preferred because simpler to implement and less computationally demanding. The variational approach, however, has the potential to discover the existence of different metastable states.
A general study of actinyl hydration by molecular dynamics simulations using
ab initio
force fields
Authors: Pérez-Conesa Sergio , Torrico Francisco , Martínez José M. , Pappalardo Rafael R. , Marcos Enrique Sánchez
Published: March 2019

A set of new ab initio force fields for aqueous [AnO2]2+/+ (An = Np(vi,v), Pu(vi), Am(vi)) has been developed using the Hydrated Ion (HI) model methodology previously used for [UO2]2+. Except for the non-electrostatic contribution of the HI-bulk water interaction, the interaction potentials are individually parameterized. Translational diffusion coefficients, hydration enthalpies, and vibrational normal mode frequencies were calculated from the MD simulations. Physico-chemical properties satisfactorily agree with experiments validating the robustness of the force field strategy. The solvation dynamics and structure for all hexavalent actinoids are extremely similar and resemble our previous analysis of the uranyl cation. This supports the idea of using the uranyl cation as a reference for the study of other minor actinyls. The comparison between the NpO22+ and NpO2+ hydration only provides significant differences in first and second shell distances and second-shell mean residence times. We propose a single general view of the [AnO2]2+/+ hydration structure: aqueous actinyls are amphiphilic anisotropic solutes which are equatorially conventional spherically symmetric cations capped at the poles by clathrate-like water structures.
Fluid dynamics of the slip boundary condition for isothermal rimming flow with moderate inertial effects
Authors: Nicholson J. M. P. , Power H. , Tammisola O. , Hibberd S. , Kay E. D.
Published: March 2019

Motivated by evaluating coating oil films within bearing chambers in an aero-engine application, an analysis is presented for the fluid dynamics relevant in their dual capacity as both the coolant and lubricant in highly sheared flows that may approach microscale thickness. An extended model is developed for isothermal rimming flow driven by substantial surface shear within a stationary cylinder. In particular, a partial slip condition replaces the no-slip condition at the wall whilst retaining inertial effects relevant to an intrinsic high speed operation. A depth-averaged formulation is presented that includes appropriate inertial effects at leading-order within a thin film approximation that encompasses a more general model of assessing the impact of surface slip. Non-dimensional mass and momentum equations are integrated across the film depth yielding a one dimensional problem with the a priori assumption of local velocity profiles. The film flow solutions for rimming flow with wall slip are modeled to a higher order than classical lubrication theory. We investigate the impact of wall slip on the transition from pooling to uniform films. Numerical solutions of film profiles are provided for the progressively increased Reynolds number, within a moderate inertia regime, offering evaluation into the effect of film slippage on the dynamics of rimming flow. We find that slip allows non-unique solution regions and existence of multiple possible steady state solutions evaluated in transforming from smooth to pooling film solutions. Additionally, boundary slip is shown to enhance the development of recirculation regions within the film which are detrimental to bearing chamber flows.