bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative volatile compounds and primary metabolites profiling of pitaya fruit peel after ozone treatment
Authors: Wu Qixian , Zhang Zhengke , Zhu Hong , Li Taotao , Zhu Xiangrong , Gao Huijun , Yun Ze , Jiang Yueming
Published: November 2018

BACKGROUND

Ozone treatment can effectively inhibit fruit decay in many fruits during postharvest storage. However, little information is available for pitaya fruit.

RESULTS

Ozone treatment significantly reduced the decay rate and induced the enzyme activities of peroxidase and polyphenol oxidase, and also reduced the levels of reactive oxygen species. In total, 103 metabolites were detected and changed the content after ozone treatment, including 54 primary metabolites and 49 aromatic compounds. After significance and importance analysis, 37 metabolites were important. Some metabolites were induced by peel senescence to respond to senescence stress, including d‐fructose, d‐glucose, mannose, inositol, galactonic acid, ethanedioic acid and stearic acid. Some metabolic products of peel senescence were reduced by ozone treatment, including d‐arabinose, glucaric acid, galacturonic acid, 1‐hexanol, 4‐ethylcyclohexanol, β‐linalool, palmitoleic acid and 2‐hydroxy‐cyclopentadecanone. Some metabolites induced by ozone treatment might play a vital role in delaying the senescence and decay, including malic acid, succinic acid, pentenoic acid, eicosanoic acid, 2‐hexenal, hexanal, 2‐heptenal, 4‐heptenal, 2‐octenal and nitro m‐xylene.

CONCLUSION

Ozone treatment significantly reduced decay and prolonged shelf‐life without reducing fruit quality. In total, 37 metabolites might play an important role in ozone delayed fruit decay. © 2018 Society of Chemical Industry
Valuing nonmarket benefits of participatory sport events using willingness to travel: Payment card versus random selection with mitigation of hypothetical bias
Authors: Whitehead John C. , Wicker Pamela
Published: November 2018

This study estimates the monetary value of nonmarket benefits to participants of a cycling event using a willingness to travel question. It compares different question formats and types of data. Using 3 years of data (2014–2016) from a postrace survey (n = 976), the results show that the random selection format produces 2.1 (stated preference data) and 2.5 times (revealed preference data) higher monetary values than the payment card. The magnitude of hypothetical bias, that is, the extent to which respondents overestimate their return visitation, is 21%. Hence, monetary values are highly sensitive to question formats and types of data.
A Real‐time Color Doppler Marker for Echocardiographic Guidance of an Acoustically Active Extracorporeal Membrane Oxygenation Cannula
Authors: Belohlavek Marek , Katayama Minako , Vaitkus Veronica V. , Kumar Viksit , Fatemi Mostafa , Grabham Jason , Sandweiss Bryan
Published: November 2018

B‐mode ultrasound imaging guidance of cannulas can be compromised by noise, artifacts, and echogenicity that is not distinctive from that of surrounding anatomy. We have modified a venovenous extracorporeal membrane oxygenation cannula by embedding piezoelectric crystals into each of its 3 blood flow ports. Each vibrating crystal acoustically interacts with a Doppler imaging signal and produces an instantaneous color marker. The aim of this study was to compare identification of the extracorporeal membrane oxygenation cannula ports by B‐mode imaging versus the color Doppler marker. Unlike B‐mode imaging, the color Doppler marker identified the corresponding port even in highly challenging closed‐chest scans in anesthetized pigs. The method could improve guidance accuracy of cannulas by ultrasound scans.
Photo‐Induced Hydrogel Formation Based on g‐C3N4 Nanosheets with Self‐Cross‐Linked 3D Framework for UV Protection Application
Authors: Ye Boyong , Yao Chengkai , Yan Mengdie , Zhang Huanhuan , Xi Fengna , Liu Jiyang , Li Benxia , Dong Xiaoping
Published: November 2018

Composite hydrogels of graphitic carbon nitride nanosheets (CNNS) and polyacrylamide (PAM) with superior UV absorption and visible transparence capabilities are reported. CNNS is employed not only as a photocatalytic initiator to trigger the polymerization of acrylamide, but also as a cross‐linker to 3D connected PAM chains via hydrogen bonds. The obtained CNNS/PAM hydrogels are highly moldable for preparing various forms, and have good mechanical properties, self‐healing ability, and photo‐stability. Furthermore, the composite hydrogels have a wide spectral range for UV absorption compared to conventional UV protective materials. Besides the complete screening of UVB (280–315 nm) in sun radiation, the CNNS/PAM hydrogel film can also filter >95% UVA radiation (315–400 nm) by regulating the coating thickness, meanwhile retaining a high visible transmittance. Therefore, the CNNS/PAM hydrogels have potential applications for shielding UV radiation. Additionally, this strategy provides a common and facile route to fabricate functional composite hydrogels via photo‐induced polymerization.
Oligo‐Urea with No Alkylene Unit Self‐Assembles into Rod‐Like Objects in Water
Authors: Han Shuaiyuan , Nicol Erwan , Niepceron Frédérick , Colombani Olivier , Pensec Sandrine , Bouteiller Laurent
Published: November 2018

Long and rigid objects formed by self‐assembly in water are useful as templates or for their rheological or biological properties. They are usually obtained by combining hydrogen bonding and strong hydrophobic interactions brought by an alkyl or alkylene chain. A simple access to well‐defined rod‐like assemblies in water is reported based on a penta‐urea sticker directly connected to poly(ethylene oxide) side chains. These assemblies are characterized by an average length of several hundreds of nanometers and a monodisperse radius (4.5 nm) resulting from a reduced lateral aggregation of the stickers.
Quaternization of a Polystyrene‐block‐poly(4‐vinylpyridine) Isoporous Membrane: An Approach to Tune the Pore Size and the Charge Density
Authors: Zhang Zhenzhen , Rahman Md. Mushfequr , Abetz Clarissa , Bajer Barbara , Wang Jiali , Abetz Volker
Published: November 2018

Isoporous integral asymmetric membranes derived from the self‐assembly of block copolymers combined with the non‐solvent‐induced phase separation (SNIPS) have gained great attention. To extend their utility, good control over pore size and surface functionality in a facile manner is highly desirable. Here, an approach is proposed to achieve this by quaternization of the poly(4‐vinylpyridine) moiety of a polystyrene‐block‐poly(4‐vinylpyridine) SNIPS membrane using alkyl iodides via a scalable gas‐solid heterogeneous reaction. By changing the size of the alkyl groups of the quaternization agent and the degree of quaternization, the effective pore size of the membrane is tailored in a wide range from the ultrafiltration to the nanofiltration regime. A quaternization of approximately half of the 4VP repeating units of the membranes with methyl iodide, ethyl iodide, or 1‐propyl iodide leads to a retention of methylene blue from a 10 mg L−1 aqueous solution of 96%, 87%, and 83%, respectively.
Asset pricing for an affine jump‐diffusion model using an FD method of lines on nonuniform meshes
Authors: Soleymani Fazlollah , Akgül Ali
Published: November 2018

We present a novel numerical scheme for the valuation of options under a well‐known jump‐diffusion model. European option pricing for such a case satisfies a 1 + 2 partial integro‐differential equation (PIDE) including a double integral term, which is nonlocal. The proposed approach relies on nonuniform meshes with a focus on the discontinuous and degenerate areas of the model and applying quadratically convergent finite difference (FD) discretizations via the method of lines (MOL). A condition for observing the time stability of the fully discretized problem is given. Also, we report results of numerical experiments.
A note on the matrix Sturm‐Liouville operators with principal functions
Authors: Yokus Nihal , Coskun Nimet
Published: November 2018

In this study, we take under investigation principal functions corresponding to the eigenvalues and the spectral singularities of the Operator L generated in
by the differential expression
and the boundary condition (A0 + A1λ + A2λ2)y′(0,λ) − (B0 + B1λ + B2λ2)y(0,λ) = 0, where Q is a matrix‐valued function and Ai,Bi,i = 0,1,2 are non‐selfadjoint matrices also A2,B2 are invertible.
Circularly polarized 2 × 2 microstrip antenna array for application as a reflectarray feed
Authors: Farias Roger L. , Peixeiro Custódio , Heckler Marcos V. T.
Published: November 2018

This article describes a circularly polarized 2 × 2 microstrip antenna array with corporate feeding to be used at K‐Band (18.7‐19.2 GHz) as a reflectarray feed. A design approach is proposed for the improvement of axial ratio and impedance bandwidths of circularly polarized microstrip antenna arrays with sequential rotation. A parametric analysis is also proposed to evaluate accurately the array phase center position. An array prototype has been designed, fabricated, and tested. The good agreement obtained between simulation and experimental results provides validation of the design approach and proof of the proposed concept.
Technical Note: EPID's response to 6 MV photons in a strong, parallel magnetic field
Authors: Rathee Satyapal , Fallone B. Gino , Steciw Stephen
Published: November 2018

Purpose

Electronic portal imaging devices (EPIDs) are potentially useful for dosimetric verification in integrated MRI‐linac systems. This work presents the reproducibility, linearity, image lag, and radiation field profiles in a conventional EPID, with and without a 0.5 T parallel magnetic field present in a 6 MV photon beam.

Methods

An aS500 EPID was modified to function in strong magnetic fields. All measurements were made using the linac‐MR installed at the Cross Cancer Institute. The EPID remained stationary on the couch between the measurements made with and without magnetic field. We measured short‐term reproducibility of dark and flood fields, signal linearity from 1 to 500 MU irradiations, and image lag post 100 MU irradiation. An ion chamber was used to measure any linac output variations to correct the EPID signal due to these variations for the duration of experiment. X‐axis and Y‐axis radiation field profiles were obtained from the EPID image resulting from a 10 × 10 cm2 radiation field delivery.

Results

The average pixel value (±standard deviation) of flood field with and without magnetic fields were 57,876 ± 379 and 57,703 ± 366, respectively, and the corresponding average dark field pixel values were −32.05 ± 0.85 and −32.19 ± 0.97. The maximum difference in image linearity data with and without magnetic field is 0.2% which is well within the measurement uncertainty of 0.65%. Similarly, the image lag curves, with and without the magnetic field, were nearly identical. The first measured point, with mean lag signal of 1.44% without and 1.41% with magnetic field, shows that the largest difference is well below the uncertainty in the EPID signal measurement. The radiation field profiles obtained with and without magnetic fields were nearly identical; 91.3% of the X‐axis and 95.2% of the Y‐axis profile points pass a gamma criterion of 1% and 1 mm.

Conclusions

A conventional EPID imager with a 0.1 cm copper plate responds to 6 MV photons similarly irrespective of the strong magnetic field being off or on in the parallel orientation to the radiation beam. Thus, the EPID is a potentially useful tool for pretreatment dosimetric verification in linac‐MR systems using parallel magnetic field.
CT automated exposure control using a generalized detectability index
Authors: Khobragade P. , Rupcich Franco , Fan Jiahua , Crotty Dominic J. , Kulkarni Naveen M. , O'Connor Stacy D. , Foley W. Dennis , Schmidt Taly Gilat
Published: November 2018

Purpose

Identifying an appropriate tube current setting can be challenging when using iterative reconstruction due to the varying relationship between spatial resolution, contrast, noise, and dose across different algorithms. This study developed and investigated the application of a generalized detectability index () to determine the noise parameter to input to existing automated exposure control (AEC) systems to provide consistent image quality (IQ) across different reconstruction approaches.

Methods

This study proposes a task‐based automated exposure control (AEC) method using a generalized detectability index (). The proposed method leverages existing AEC methods that are based on a prescribed noise level. The generalized metric is calculated using lookup tables of task‐based modulation transfer function (MTF) and noise power spectrum (NPS). To generate the lookup tables, the American College of Radiology CT accreditation phantom was scanned on a multidetector CT scanner (Revolution CT, GE Healthcare) at 120 kV and tube current varied manually from 20 to 240 mAs. Images were reconstructed using a reference reconstruction algorithm and four levels of an in‐house iterative reconstruction algorithm with different regularization strengths (IR1–IR4). The task‐based MTF and NPS were estimated from the measured images to create lookup tables of scaling factors that convert between and noise standard deviation. The performance of the proposed ‐AEC method in providing a desired IQ level over a range of iterative reconstruction algorithms was evaluated using the American College of Radiology (ACR) phantom with elliptical shell and using a human reader evaluation on anthropomorphic phantom images.

Results

The study of the ACR phantom with elliptical shell demonstrated reasonable agreement between the predicted by the lookup table and measured in the images, with a mean absolute error of 15% across all dose levels and maximum error of 45% at the lowest dose level with the elliptical shell. For the anthropomorphic phantom study, the mean reader scores for images resulting from the ‐AEC method were 3.3 (reference image), 3.5 (IR1), 3.6 (IR2), 3.5 (IR3), and 2.2 (IR4). When using the ‐AEC method, the observers’ IQ scores for the reference reconstruction were statistical equivalent to the scores for IR1, IR2, and IR3 iterative reconstructions (P > 0.35). The ‐AEC method achieved this equivalent IQ at lower dose for the IR scans compared to the reference scans.

Conclusions

A novel AEC method, based on a generalized detectability index, was investigated. The proposed method can be used with some existing AEC systems to derive the tube current profile for iterative reconstruction algorithms. The results provide preliminary evidence that the proposed ‐AEC can produce similar IQ across different iterative reconstruction approaches at different dose levels.
A sparse representation‐based radiomics for outcome prediction of higher grade gliomas
Authors: Wu Guoqing , Shi Zhifeng , Chen Yinsheng , Wang Yuanyuan , Yu Jinhua , Lv Xiaofei , Chen Liang , Ju Xue , Chen Zhongping
Published: November 2018

Purpose

Accurately predicting outcome (i.e., overall survival (OS) time) for higher grade glioma (HGG) has great clinical value and would provide optimized guidelines for treatment planning. Radiomics focuses on revealing underlying pathophysiological information in biomedical images for disease analysis and demonstrates promising prognostic clinical performance. In this paper, we propose a novel sparse representation‐based radiomics framework to predict if HGG patients would have long or short OS time.

Methods

First, taking advantages of the scale invariant feature transform (SIFT) feature in image characterizing, we developed a sparse representation‐based method to convert a local SIFT descriptor into a global tumor feature. Next, because preserving sample structure is beneficial for feature selection, we proposed a locality preserving projection and sparse representation‐combined feature selection method to select more discriminative features for tumor classification. Finally, we employed a multifeature collaborative sparse representation classification to combine the information of multimodal images to classify OS time.

Results

Three experiments were performed on the two datasets provided by different institutions. Specifically, the proposed model was trained and independently tested on dataset 1 (135 subjects), on dataset 2 (86 subjects), and on the combination of dataset 1 and dataset 2, respectively. Experimental results demonstrated that the proposed method achieved encouraging prediction performance, exhibiting a testing accuracy of 93.33% on dataset 1 (one modality), 92.31% on dataset 2 (two modalities), and 87.93% on the combined dataset (one modality).

Conclusions

The sparse representation theory provides reasonable solutions to feature extraction, feature selection, and classification for radiomics. This study provides a promising tool to enhance the prediction performance of HGG patient's outcome.
Accelerated, first‐pass cardiac perfusion pulse sequence with radial k‐space sampling, compressed sensing, and k‐space weighted image contrast reconstruction tailored for visual analysis and quantification of myocardial blood flow
Authors: Naresh Nivedita K. , Haji‐Valizadeh Hassan , Aouad Pascale J. , Barrett Matthew J. , Chow Kelvin , Ragin Ann B. , Collins Jeremy D. , Carr James C. , Lee Daniel C. , Kim Daniel
Published: November 2018

Purpose

To develop an accelerated cardiac perfusion pulse sequence and test whether it is capable of increasing spatial coverage, generating high‐quality images, and enabling quantification of myocardial blood flow (MBF).

Methods

We implemented an accelerated first‐pass cardiac perfusion pulse sequence by combining radial k‐space sampling, compressed sensing (CS), and k‐space weighted image contrast (KWIC) filtering. The proposed and clinical standard pulse sequences were evaluated in a randomized order in 13 patients at rest. For visual analysis, 3 readers graded the conspicuity of wall enhancement, artifact, and noise level on a 5‐point Likert scale (overall score index = sum of 3 individual scores). Resting MBF was calculated using a Fermi function model with and without KWIC filtering. Mean visual scores and MBF values were compared between sequences using appropriate statistical tests.

Results

The proposed pulse sequence produced greater spatial coverage (6–8 slices) with higher spatial resolution (1.6 × 1.6 × 8 mm3) and shorter readout duration (78 ms) compared to clinical standard (3–4 slices, 3 × 3 × 8 mm3, 128 ms, respectively). The overall image score index between accelerated (11.1 ± 1.3) and clinical standard (11.2 ± 1.3) was not significantly different (P = 0.64). Mean resting MBF values with KWIC filtering (0.9–1.2 mL/g/min across different slices) were significantly lower (P < 0.0001) than those without KWIC filtering (3.1–4.3 mL/g/min) and agreed better with values reported in literature.

Conclusion

An accelerated, first‐pass cardiac perfusion pulse sequence with radial k‐space sampling, CS, and KWIC filtering is capable of increasing spatial coverage, generating high‐quality images, and enabling quantification of MBF.
Retrospective artifact elimination in MEGA‐PRESS using a correlation approach
Authors: Tapper Sofie , Tisell Anders , Helms Gunther , Lundberg Peter
Published: November 2018

Purpose

To develop a method for retrospective artifact elimination of MRS data. This retrospective method was based on an approach that combines jackknife analyses with the correlation of spectral windows, and therefore termed “JKC.”

Methods

Twelve healthy volunteers performed 3 separate measurement protocols using a 3T MR system. One protocol consisted of 2 cerebellar MEGA‐PRESS measurements: 1 reference and 1 measurement including head movements. One‐third of the artifact‐influenced datasets were treated as training data for the implementation the JKC method, and the rest were used for validation.

Results

The implemented JKC method correctly characterized most of the validation data. Additionally, after elimination of the detected artifacts, the resulting concentrations were much closer to those computed for the reference datasets. Moreover, when the JKC method was applied to the reference data, the estimated concentrations were not affected, compared with standard averaging.

Conclusion

The implemented JKC method can be applied without any extra cost to MRS data, regardless of whether the dataset has been contaminated by artifacts. Furthermore, the results indicate that the JKC method could be used as a quality control of a dataset, or as an indication of whether a shift in voxel placement has occurred during the measurement.
Robust retrospective frequency and phase correction for single‐voxel MR spectroscopy
Authors: Wilson Martin
Published: November 2018

Purpose

Subject motion and static field (B0) drift are known to reduce the quality of single voxel MR spectroscopy data due to incoherent averaging. Retrospective correction has previously been shown to improve data quality by adjusting the phase and frequency offset of each average to match a reference spectrum. In this work, a new method (RATS) is developed to be tolerant to large frequency shifts (>7 Hz) and baseline instability resulting from inconsistent water suppression.

Methods

In contrast to previous approaches, the variable‐projection method and baseline fitting is incorporated into the correction procedure to improve robustness to fluctuating baseline signals and optimization instability. RATS is compared to an alternative method, based on time‐domain spectral registration (TDSR), using simulated data to model frequency, phase, and baseline instability. In addition, a J‐difference edited glutathione in‐vivo dataset is processed using both approaches and compared.

Results

RATS offers improved accuracy and stability for large frequency shifts and unstable baselines. Reduced subtraction artifacts are demonstrated for glutathione edited MRS when using RATS, compared with uncorrected or TDSR corrected spectra.

Conclusions

The RATS algorithm has been shown to provide accurate retrospective correction of SVS MRS data in the presence of large frequency shifts and baseline instability. The method is rapid, generic and therefore readily incorporated into MRS processing pipelines to improve lineshape, SNR, and aid quality assessment.
Quantifying the Net Benefits of Suppression: Truncated Size Structure and Consumption of Native Salmonids by Invasive Northern Pike in an Alaska Lake
Authors: Courtney Michael B. , Schoen Erik R. , Wizik Andy , Westley Peter A. H.
Published: November 2018

Predation by nonnative Northern Pike Esox lucius is implicated in the decline of native salmonid Oncorhynchus spp. populations in south-central Alaska. In response to the ongoing invasion of Northern Pike, eradication and suppression programs are under way in several severely impacted watersheds throughout the region. As previous research indicates that owing to the particular composition of their diet small Northern Pike may have disproportionate impacts on juvenile Pacific salmon Oncorhynchus spp. (hereafter, “salmon”) populations, there is a potentially important trade-off between overall predator reduction and truncation of the size structure of the population. We examined this trade-off using bioenergetics models and field data collected during a 5-year Northern Pike suppression program in Shell Lake, a heavily impacted Sockeye Salmon O. nerka nursery lake in the Susitna River drainage of south-central Alaska. Our results confirm that Northern Pike of all sizes consumed salmon and that on average salmon made up a smaller proportion of the diets of large Northern Pike. However, large Northern Pike consumed more salmon biomass per capita than smaller Northern Pike, according to the bioenergetics model incorporating size-dependent metabolic needs. Compared with the period prior to initiation of suppression efforts in 2013, Northern Pike consumed 68% less salmon in 2014, 87% less in 2015, and 88% less in 2016. Despite the fact that the catches are now dominated by smaller and younger Northern Pike, the suppression program has been highly effective at reducing the consumption of salmon in Shell Lake, with stark reductions in the catch of all size- and age-classes. Importantly, the reduction in the abundance of the oldest (age 5) Northern Pike to near zero was an key element in this reduction in predator consumption. Therefore, we conclude that suppression strategies targeting a broad range of size-classes of Northern Pike are more likely to be effective at reducing the consumption of salmon than strategies targeting only smaller size-classes.
Highly efficient optical aggregation network with network functions virtualization
Authors: Miyamura Takashi , Misawa Akira , Kani Jun‐ichi
Published: November 2018

Network functions virtualization enables network edge functions to be relocated from dedicated hardware to distributed pools of commodity servers. Metro aggregation networks provide transport between access gateway nodes and such servers accommodating virtual network functions (VNFs). Networks need to be designed to increase the efficiency of network resource usage and reducing network cost as well as energy consumption. However, independently placing VNFs on a server from a physical network design degrades the efficiency of resource usage and causes an increase in network cost. We can avoid such problems by adequately placing each VNF in consideration of the location of access gateway nodes and a network topology. We thus propose a method for designing an optical aggregation network with VNF placement. We successfully formulate the design method as mixed‐integer linear programming and demonstrate its effectiveness through intensive mathematical experiments. The experiments showed that the proposed method reduced network cost by up to about 18% while performing almost optimally in terms of server load dispersion.
The Rising Cost of Diabetes: Can DiRECT Tip the Scales?
Authors: Venker Brett T. , Dunn Julia P. , Stephenson Kevin
Published: November 2018

The cost of treating diabetes mellitus has risen sharply in recent years because of an increasing number of patients with type 2 diabetes and obesity and a rapidly expanding repertoire of expensive nongeneric medications. Despite the call for a new treatment paradigm by the American Diabetes Association to mitigate this cost, recent Medicare Part D expenditure data show that this call remains unanswered. The Diabetes Remission Clinical Trial, published in The Lancet, adds support to a different path, demonstrating success with intensive lifestyle intervention followed by structured support for long‐term weight loss maintenance. Nearly half of patients enrolled were able to achieve remission of their diabetes with hemoglobin A1c < 6.5% and an improvement of their quality of life. Although only from one trial, and of limited duration, these results should provide optimism for providers and patients alike and support future work toward an evidence base for non–medication‐based management of diabetes.
Mechanical properties of gamma‐irradiated styrene‐butadiene rubber/acid‐treated vermiculite clay/maleic anhydride nanocomposites
Authors: El‐Nemr Khaled F. , Ali Magdy A.M. , Saleh Saleh N. , El‐Naggar Abdel Wahab M.
Published: November 2018

Nanoparticle vermiculite (VMT) clay was prepared by treatment with hydrochloric acid. Styrene‐butadiene rubber (SBR) nanocomposites were prepared by mixing different contents (2.5, 5, 7.5, and 10 phr) of untreated (VMT) and acid‐treated (DVMT) vermiculite clay, respectively. In addition, different contents (3, 7, and 10 phr) of maleic anhydride (MA) as compatibilizer were mixed via direct melt compounding in internal mixer. The effect of gamma irradiation, VMT clay, and MA contents on the mechanical properties was studied. The acid‐treated VMT clay was characterized by x‐ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FT‐IR) spectroscopy. Meanwhile, the SBR/VMT composites, SBR/DVMT, and SBR/DVMT/MA nanocomposites were characterized via crosslinking density and tensile mechanical testing and FT‐IR spectroscopic analysis. The results indicated that good yield of nanoparticle vermiculite was achieved when the acid treatment was carried out for 120 h. In addition, the results showed that the presence of DVMT clay improved the chemical bonding in the SBR nanocomposites and hence their mechanical properties. The highest improvement was obtained when the contents of DVMT clay, MA, and irradiation dose were 10 phr, 3 phr, and 100 kGy, respectively. POLYM. ENG. SCI., 59:355–364, 2019. © 2018 Society of Plastics Engineers
Does Cooperation in the Laboratory Reflect the Operation of A Broad Trait?
Authors: McAuliffe William H.B. , Forster Daniel E. , Pedersen Eric J. , McCullough Michael E.
Published: November 2018

The Dictator Game, a face valid measure of altruism, and the Trust Game, a face valid measure of trust and trustworthiness, are among the most widely used behavioural measures in human cooperation research. Researchers have observed considerable covariation among these and other economic games, leading them to assert that there exists a general human propensity to cooperate that varies in strength across individuals and manifests itself across a variety of social settings. To formalize this hypothesis, we created an S–1 bifactor model using 276 participants’ Dictator Game and Trust Game decisions. The general factor had significant, moderate associations with self–reported and peer–reported altruism, trust, and trustworthiness. Thus, the positive covariation among economic games is not reducible to the games’ shared situational features. Two hundred participants returned for a second session. The general factor based on Dictator Game and Trust Game decisions from this session did not significantly predict self–reported and peer–reported cooperation, suggesting that experience with economic games causes them to measure different traits from those that are reflected in self–assessments and peer–assessments of cooperativeness. © 2018 European Association of Personality Psychology
iSEE: Interface structure, evolution, and energy‐based machine learning predictor of binding affinity changes upon mutations
Authors: Geng Cunliang , Vangone Anna , Folkers Gert E. , Xue Li C. , Bonvin Alexandre M. J. J.
Published: November 2018

Quantitative evaluation of binding affinity changes upon mutations is crucial for protein engineering and drug design. Machine learning‐based methods are gaining increasing momentum in this field. Due to the limited number of experimental data, using a small number of sensitive predictive features is vital to the generalization and robustness of such machine learning methods. Here we introduce a fast and reliable predictor of binding affinity changes upon single point mutation, based on a random forest approach. Our method, iSEE, uses a limited number of interface Structure, Evolution, and Energy‐based features for the prediction. iSEE achieves, using only 31 features, a high prediction performance with a Pearson correlation coefficient (PCC) of 0.80 and a root mean square error of 1.41 kcal/mol on a diverse training dataset consisting of 1102 mutations in 57 protein‐protein complexes. It competes with existing state‐of‐the‐art methods on two blind test datasets. Predictions for a new dataset of 487 mutations in 56 protein complexes from the recently published SKEMPI 2.0 database reveals that none of the current methods perform well (PCC < 0.42), although their combination does improve the predictions. Feature analysis for iSEE underlines the significance of evolutionary conservations for quantitative prediction of mutation effects. As an application example, we perform a full mutation scanning of the interface residues in the MDM2–p53 complex.
On the Optimization of Magneto‐Volume Coupling for Practical Applied Field Magnetic Refrigeration
Authors: Davarpanah Amin , Belo Joao H. , Amaral Vitor. S. , Amaral Joao S.
Published: November 2018

Materials with strong magneto‐volume coupling can present a coupled first‐order magnetic and structural transition and a giant magnetocaloric effect. The trade‐off of the resulting increased entropy change is hysteresis, and incomplete transition when the applied field is <2 T, implying that the full cooling capacity of the refrigerant is not harnessed. In this work, the behavior of the magnetic entropy change as a function of temperature is simulated, considering the Bean–Rodbell model, for various spin systems with Curie temperatures close to room temperature. Increasing magneto‐volume coupling parameter (η) results in higher entropy change peak value (ΔSMmax), together with a narrowing of entropy change function ΔSM(T), limiting the working temperature range. Accordingly, cooling capacity behaves non‐monotonously, reaching a peak value at ηMAX, which departs from the tri‐critical point as H increases up to 2 T. By tuning η, the cooling capacity can be considerably larger than the uncoupled system (up to 15–40% for low applied fields). Such tuning can be accomplished experimentally through proper chemical substitution. A universal behavior of cooling capacity as a function of ηMAX underlines that the performance of magnetic refrigerant is optimized, by tuning magneto‐volume coupling within the second order range, rather than the tri‐critical region.
Concise Review: Lessons Learned from Islet Transplant Clinical Trials in Developing Stem Cell Therapies for Type 1 Diabetes
Authors: Welsch Carole A. , Rust William L. , Csete Marie
Published: November 2018

We examined data and patterns in clinical islet transplant studies registered on ClinicalTrials.gov (CTgov) for treatment of type 1 diabetes (T1D), with a goal of extracting insights to apply in the design of a pluripotent stem cell-derived islet therapy. Clinical islet transplantation, as a cell therapy (rather than solid organ transplant) is a unique precedent for stem cell-based islet therapies. Registration activity shows that the field is not growing significantly, and newer registrations suggest that the reasons for stagnation include need for a more optimal site of infusion/transplantation, and especially a need for better immune protective strategies to advance a more effective and durable therapy for T1D. Stem Cells Translational Medicine  2019;8:209&214
P3HT/Phthalocyanine Nanocomposites as Efficient Hole‐Transporting Materials for Perovskite Solar Cells
Authors: Hu Qikun , Rezaee Ehsan , Dong Qingshun , Shan Haiquan , Chen Qian , Wang Liduo , Liu Bingchen , Pan Jia‐Hong , Xu Zong‐Xiang
Published: November 2018

New efficient hole‐transport material (HTM) composites based on low‐cost easy‐preparation non‐peripheral octamethyl‐substituted copper (II) phthalocyanine (N‐CuMe2Pc) nanowire and poly(3‐hexylthiophene) (P3HT) are developed for CH3NH3PbI3 (MAPbI3)‐based perovskite solar cells (PSCs). Compared with pristine P3HT, the prepared nanocomposite HTMs provided thin films with better qualities and reduced trap densities, and exhibited higher hole mobilities and well‐matched energy levels with the perovskite layer. Depending on the ratio of the two components, the power conversion efficiency (PCE) reached up to 16.61%, which is higher than the efficiency of the standard device based on doped spiro‐OMeTAD (16.13%). Moreover, the long‐term stability of the PSCs is also improving greatly. The best performing devices based on P1C1 HTM retained 90% of their initial efficiencies after 800 h of storage with a relative humidity of 75%. These results indicate N‐CuMe2Pc nanowire/P3HT nanocomposites can be an effective HTM to realize superior performance in PSCs.
Optical Analysis for Semitransparent Organic Solar Cells
Authors: Xia Ruoxi , Gu Honggang , Liu Shiyuan , Zhang Kai , Yip Hin‐Lap , Cao Yong
Published: November 2018

Semitransparent organic solar cells (STOSCs) show great potential for application as power generating windows for buildings. The power conversion efficiency (PCE) and the average visible transmittance (AVT) are both important parameters with which to evaluate the overall performance of STOSCs. However, it is very challenging to simultaneously improve these two performance parameters because they are intrinsically contradictory to each other. In this work, the optical and photovoltaic properties of STOSCs are investigated based on two model samples including PTB7‐Th:PC61BM and PTB7‐Th:PC71BM by systematically tuning their device structures. By combining optical modeling and experimental results, a full optical analysis is provided for the STOSCs with details on photon harvesting, optical losses, transmission properties, energy distribution spectrum, electric field intensity distribution, and photon absorption rate distribution within the devices. Defined as the sum of the external quantum efficiency and the transmittance, the term “quantum utilization efficiency” is used as a subjective parameter to describe the light energy use in the semitransparent devices, which provides an alternative angle for analyzing STOSCs.
Effects of Blast Furnace Main Trough Geometry on the Slag‐Metal Separation Based on Numerical Simulation
Authors: Kou Mingyin , Yao Shun , Wu Shengli , Zhou Heng , Xu Jian
Published: November 2018

The complete separation of hot metal from slag is expected in the main trough of a blast furnace. However, in practice slag may take some hot metals away when it goes through the slag port. Therefore, it is important to optimize the slag‐metal separation in order to decrease the metal loss associated with the slag. The present work establishes a three dimensional unsteady model of the main trough of a blast furnace in Panzhihua Steel. The model is then applied to investigate the effects of the width, depth, and bottom slope on the flow behavior and slag‐metal separation. The results show that the high velocity regions and the velocity difference between the hot metal and slag are the main cause of hot metal drawn into the slag. The change of main trough geometry has a major impact on the flow behavior and slag‐metal separation. The slag‐metal separation is improved a lot by decreasing the bottom slope of the main trough or increasing its width. Therefore, it is strongly recommended that the main trough have a horizontal bottom or that its width be increased in order to obtain a better slag‐metal separation.
Zum Biegedrillknicken von Verbundträgern
Authors: Hanswille Gerhard , Lindner Joachim , Münich Dieter
Published: November 2018

Faksimile aus „Der Stahlbau 67 (1998), H. 7, S. 525–535”
Why the social cost of carbon will always be disputed
Authors: Pezzey John C. V.
Published: November 2018

Any social cost of carbon (SCC) calculated from an integrated assessment model of global climate‐economy interactions will always be disputed. This is because a key model input–namely the valuation of centennial climate damage–is highly unknowable for fundamental reasons discussed here. Problems with damage valuation are highlighted by the implicit implausibility to climate scientists of a leading model's (centennial) damage function, and by strong criticisms of damage functions by many climate economists. The claim that statistical analyses of past weather impacts on local economies, combined with structural modeling of sectoral impacts, can significantly improve centennial damage valuation rests on untestable, far‐out‐of‐sample extrapolation. Testing centennial climate (natural) science projections is generally harder than testing predictions in astronomy, geology and other earth sciences, because of Earth's uniqueness, and the unprecedented degree of likely climate change; but stable underlying laws make climate modeling based on past observations meaningful. By contrast, the added complexity of human behavior means there are no quantitatively stable laws for modeling the value of centennial climate damage. I suggest that any carbon prices used to inform climate policies, be they carbon prices used as policy instruments, or complementary, non‐carbon‐price policies, should instead be based on marginal abatement costs, found by modeling low‐cost pathways to socially agreed, physical climate targets. A pathway approach to estimating carbon prices poses challenges to many economists, and is no panacea, but it avoids any illusion of optimality, and facilitates detailed analysis of sectoral policies.

This article is categorized under:

Climate Economics > Aggregation Techniques for Impacts and Mitigation Costs

Assessing Impacts of Climate Change > Evaluating Future Impacts of Climate Change
Shared neural and cognitive mechanisms in action and language: The multiscale information transfer framework
Authors: Blumenthal‐Dramé Alice , Malaia Evie
Published: November 2018

This review compares how humans process action and language sequences produced by other humans. On the one hand, we identify commonalities between action and language processing in terms of cognitive mechanisms (e.g., perceptual segmentation, predictive processing, integration across multiple temporal scales), neural resources (e.g., the left inferior frontal cortex), and processing algorithms (e.g., comprehension based on changes in signal entropy). On the other hand, drawing on sign language with its particularly strong motor component, we also highlight what differentiates (both oral and signed) linguistic communication from nonlinguistic action sequences. We propose the multiscale information transfer framework (MSIT) as a way of integrating these insights and highlight directions into which future empirical research inspired by the MSIT framework might fruitfully evolve.

This article is categorized under:

Psychology > Language

Linguistics > Language in Mind and Brain

Psychology > Motor Skill and Performance

Psychology > Prediction
Rembrandt's Old Woman Praying, 1629/30: A look below the surface using X‐ray fluorescence mapping
Authors: Uhlir Katharina , Gironda Michele , Bombelli Luca , Eder Michael , Aresi Nicola , Groschner Gabriele , Griesser Martina
Published: November 2018

Rembrandt's painting Old Woman Praying, 1629/30, is the most valuable and exceptional work of art of the Residenzgalerie Salzburg (RGS). It is painted on a gilded copper plate with dimensions of only approximately 15 × 12 cm. The painting probably belongs to a series of three small‐scale tronies, all executed on gilded copper plates. This particular picture preparation, which represents a special feature in Rembrandt's work, is quite unusual in the history of art.

Previous investigations on the comparable paintings The Laughing Man, 1629/30, in the Mauritshuis, The Hague and the Self Portrait, 1630, in the National Museum, Stockholm showed that the gilding of the copper plate was applied over a lead white ground.

To characterize the painting in the RGS, X‐ray fluorescence (XRF) mapping was performed in a collaboration between the Research Office Residenzgalerie, Land Salzburg, the XGLab S.R.L, Milan, and the Conservation Science Department of the Kunsthistorische Museum Vienna (KHM). The results indicate a different structure for this painting than that used for The Laughing Man and the Self Portrait. The gilding was applied directly onto the copper plate, but with three areas with the gilding missing. It seems likely that in these sections, the gold was purposely removed to provide a different darker effect.

XRF mapping yielded valuable insights into the structure of the painting and its technique as well as the principal pigments used for its composition.
On a Generalization of Local Independence in Item Response Theory Based on Knowledge Space Theory
Authors: Noventa Stefano , Spoto Andrea , Heller Jürgen , Kelava Augustin
Published: November 2018

Knowledge space theory (KST) structures are introduced within item response theory (IRT) as a possible way to model local dependence between items. The aim of this paper is threefold: firstly, to generalize the usual characterization of local independence without introducing new parameters; secondly, to merge the information provided by the IRT and KST perspectives; and thirdly, to contribute to the literature that bridges continuous and discrete theories of assessment. In detail, connections are established between the KST simple learning model (SLM) and the IRT General Graded Response Model, and between the KST Basic Local Independence Model and IRT models in general. As a consequence, local independence is generalized to account for the existence of prerequisite relations between the items, IRT models become a subset of KST models, IRT likelihood functions can be generalized to broader families, and the issues of local dependence and dimensionality are partially disentangled. Models are discussed for both dichotomous and polytomous items and conclusions are drawn on their interpretation. Considerations on possible consequences in terms of model identifiability and estimation procedures are also provided.
Decision tree supports the interpretation of CSF biomarkers in Alzheimer's disease
Authors: Babapour Mofrad Rosha , Schoonenboom Niki S.M. , Tijms Betty M. , Scheltens Philip , Visser Pieter Jelle , van der Flier Wiesje M. , Teunissen Charlotte E.
Published: November 2018

Introduction

We developed and validated a clinically applicable decision tree for the use of cerebrospinal fluid biomarkers in the diagnosis of Alzheimer's disease (AD).

Methods

Subjects with probable AD (n = 1004) and controls (n = 442) were included. A decision tree was modeled using Classification And Regression Tree analysis in a training cohort (AD n = 221; controls n = 221) and validated in an independent cohort (AD n = 783; controls n = 221). Diagnostic performance was compared to previously defined cutoffs (amyloid β 1‐42 < 813 pg/ml; tau>375 pg/ml).

Results

Two cerebrospinal fluid AD biomarker profiles were revealed: the “classical” AD biomarker profile (amyloid β 1‐42: 647‐803 pg/ml; tau >374 pg/ml) and an “atypical” AD biomarker profile with strongly decreased amyloid β 1‐42 (<647 pg/ml) and normal tau concentrations (<374 pg/ml). Compared to previous cutoffs, the decision tree performed better on diagnostic accuracy (86% [84‐88] vs 80% [78‐83]).

Discussion

Two cerebrospinal fluid AD biomarker profiles were identified and incorporated in a readily applicable decision tree, which improved diagnostic accuracy.
A Postmodernization of Customary International Law for the First World?
Authors: d'Aspremont Jean
Published: November 2018

In his recent piece in the American Journal of International Law, B.S. Chimni depicts a doctrine of customary international law that has allowed the First World to impose its domination and promote its version of global capitalist justice. From Chimni's perspective, all the gimmicks and sophisticated dichotomies invented by international lawyers to refine international customary law serve a hegemonic socialization process whereby the center imposes its neoliberal ideals on an admiring periphery. But this diagnosis is certainly not the end of the story. In fact, Chimni's dismal image of the world and the role of custom therein is meant to foreground a more central project—i.e., the reinvention of customary international law around “the progressive ideas, beliefs, and practices of the global civil society” and geared towards the promotion of the “common good.” My view is that Chimni's postmodernization of the doctrine of international customary law does not necessarily remedy the charges he levels against custom, let alone redefine the center and the periphery. As much as I share his diagnosis about custom's complicity in hegemonic socialization and the promotion of a global capitalist ethos, I contend that Chimni's postmodernization is at best unavailing and, at worse, rehabilitative of the First World's centrality in norm-setting. Instead of striving to reinvent the doctrine of custom, we must invest in strategies that draw on the malleability and fluidity of the current doctrine and facilitate the types of argumentation that “decenter” the First World, thereby directly empowering international lawyers elsewhere.