bluuebunny/crossref_metadata_2025 huggingface dataset:
Adsorption and Electron‐Transfer Mechanisms of Ferrocene Carboxylates and Sulfonates at Highly Oriented Pyrolytic Graphite
Authors: Kurapati Niraja , Pathirathna Pavithra , Ziegler Christopher J. , Amemiya Shigeru
Published: October 2019

Ferrocene derivatives are considered as representative outer‐sphere redox couples that do not specifically interact with the electrode surface. It, however, is highly challenging to unambiguously prove their outer‐sphere character experimentally. Herein, we employ quantitative cyclic voltammetry to assess whether ferrocene carboxylates and sulfonates mediate only outer‐sphere electron transfer (ET) at highly oriented pyrolytic graphite (HOPG). We find voltammetrically that only reduced forms of ferroceneacetate, ferrocenecarboxylate, and ferrocenesulfonate are specifically adsorbed on the HOPG surface to mediate outer‐sphere ET without inner‐sphere ET, which requires the adsorption of both reduced and oxidized forms of a redox couple. By contrast, no voltammetric feature of adsorption is observed for 1,1′‐ferrocenedicarboxylate and 1,1′‐ferrocenedisulfonate to prevent us from identifying the unique mechanism among outer‐sphere ET, inner‐sphere ET, and both owing to the Laviron‐Amatore paradox.
The application of carbon materials in nonaqueous Na‐O2 batteries
Authors: Lin Xiaoting , Sun Qian , Doyle Davis Kieran , Li Ruying , Sun Xueliang
Published: October 2019

Na‐O2 batteries are advantageous as the candidates of next‐generation electric vehicles due to their ultrahigh theoretical energy density and have attracted enormous attention recently. Tremendous efforts have been devoted to improve the Na‐O2 battery performance by designing advanced electrodes with various carbon‐based materials. Carbon materials used in Na‐O2 batteries not only function as the air electrode to provide active sites and accommodate discharge products but also as Na anode protectors against dendrite growth and chemical/electrochemical corrosion. In this review, we mainly focus on the application of various carbon‐based materials in Na‐O2 batteries and highlight their advances. The scientific understanding on the fundamental design of the material microstructure and chemistry in relation to the battery performance are summarized. Finally, perspectives on enhancing the overall battery performance based on the optimization and rational design of carbon‐based cell components are also briefly anticipated.
Oxidation of Enones for Regioselective [3+2] Cycloaddition through γ‐Enone Radical Intermediates
Authors: Kan Jian , Zhang Min , Zhang Xiaofeng , Lou Xin , Shang Yaping , Xu Biping , Yang Fanyuanhang , Su Weiping
Published: October 2019

Invited for the cover of this issue is the group of Min Zhang and Weiping Su at the Fujian Institute of Research on the Structure of Matter. Read the full text of the article at 10.1002/chem.201903551.
Basics of Expansion Microscopy
Authors: Klimas Aleksandra , Gallagher Brendan , Zhao Yongxin
Published: October 2019

Optical imaging techniques are often used in neuroscience to understand brain function and discern disease pathogenesis. However, the optical diffraction limit precludes conventional optical imaging approaches from resolving nanoscopic structures with feature sizes smaller than 300 nm. Expansion microscopy (ExM) circumvents this limit by physically expanding preserved tissues embedded in a swellable hydrogel. Biomolecules of interest are covalently linked to a polymer matrix, which is then isotropically expanded at least 100‐fold in size in pure water after mechanical homogenization of the tissue‐gel. The sample can then be investigated with nanoscale precision using a conventional diffraction‐limited microscope. The protocol described here is a variant of ExM that uses regents and equipment found in a typical biology laboratory and has been optimized for imaging proteins in expanded brain tissues. © 2019 by John Wiley & Sons, Inc.

Basic Protocol: Expansion microscopy for intact brain tissue
Radiotelemetry reveals effects of upstream biomass and UV exposure on environmental DNA occupancy and detection for a large freshwater turtle
Authors: Kessler Ethan J. , Ash Kurt T. , Barratt Samantha N. , Larson Eric R. , Davis Mark A.
Published: October 2019

Background

Imperfect detection of hard‐to‐sample organisms has motivated the development of novel monitoring techniques. Environmental DNA (eDNA) can provide a sensitive, relatively low‐cost sampling method in aquatic systems, but biotic and abiotic factors can affect its reliability.

Aims

We used a reintroduced population of radio‐tracked alligator snapping turtles (Macrochelys temminckii) to test the efficacy and ecology of eDNA in a lotic system.

Materials & Methods

We collected samples at turtle locations as well as random up‐ and downstream sites. Using a novel eDNA assay, we modeled occupancy and detection of eDNA using turtle biomass and remotely sensed UV exposure and also tested the relationship between these parameters and eDNA concentration.

Results

We found eDNA occupancy was best explained by upstream biomass and detection probability decreased with greater upstream UV exposure. The concentration of eDNA in a sample was not significantly affected by biomass measures, but decreased with higher upstream UV exposure, and the effect was significant.

Discussion

Our results show that UV exposure can affect aquatic eDNA sampling in situ with free‐ranging animals. The use of radiotelemetry allowed for higher control when modeling eDNA persistence and transport in a natural setting relative to laboratory, enclosure, or mesocosm studies.

Conclusion

We propose using wildlife tracking techniques to provide added realism to studies of eDNA dynamics.
LiI/TBHP Mediated Oxidative Cross‐Coupling of P(O)–H Compounds with Phenols and Various Nucleophiles: Direct Access to the Synthesis of Organophosphates
Authors: Anitha Thippani , Ashalu Kashamalla Chinna , Sandeep Mummadi , Mohd Aabid , Wencel‐Delord Joanna , Colobert Francoise , Reddy Kallu Rajender
Published: October 2019

An efficient and mild method for the direct phosphorylation of phenols, alcohols, and amines with P(O)–H has been reported by LiI/TBHP mediated oxidative cross‐coupling reaction. Moreover, this protocol extended to β‐keto esters for the synthesis of enol phosphates using H‐phosphonates. Notably, this developed method applied for the synthesis of organopesticides such as paraoxon, cyanophos, and methyl parathion. The key features of this protocol are mild conditions, short reaction time, good functional group tolerance, and broad substrate scope.
Heuristic approaches for the reliable SDN controller placement problem
Authors: Singh Ashutosh Kumar , Maurya Saurabh , Kumar Naveen , Srivastava Shashank
Published: October 2019

Software‐defined networking (SDN) is one of the most used network architecture that divides the forwarding plane and control plane. The SDN centrally observes and regulates the network through a software control in the control plane, called as controller. Multiple controllers are needed to manage the software‐defined WAN (SD‐WAN) for handling the scalability and reliability issues of the network as one controller is not enough. Deploying numerous controllers efficiently to improve the performance of the network is known as controller placement problem (CPP). This paper proposes a Varna‐based optimization (VBO) for a reliable CPP that minimizes the total average latency of SDN. To the best of our knowledge, the proposed work is a novel approach, which is compared with particle swarm optimization, teacher learning‐based optimization, and Jaya algorithms to solve reliable CPP. The experimental results show that VBO gives better performance than teacher learning‐based optimization (TLBO), PSO, and Jaya algorithms for the popular topologies that are publicly available.
Association between pathological invasion patterns and late lymph node metastases in patients with surgically treated clinical No early oral tongue carcinoma
Authors: Hori Yukiko , Kubota Akira , Yokose Tomoyuki , Furukawa Madoka , Matsushita Takeshi , Oridate Nobuhiko
Published: October 2019

Background

This study evaluated the combination of tumor budding and depth (BD model) and worst pattern of invasion (WPOI) as histopathological prognostic factors in clinical N0 early oral tongue carcinoma.

Methods

Data from 62 patients were retrospectively analyzed. Associations between histopathological factors (differentiation, stage, lymphatic invasion, blood vessel invasion, WPOI, and BD model) and regional control (RC) or disease‐free survival (DFS) were evaluated.

Results

The five‐year RC and DFS rates were 74% and 65%, respectively. Univariate analysis identified blood vessel invasion, lymphatic invasion, WPOI, and BD model, whereas multivariate analysis identified WPOI, and BD model, as predictive factors for RC. Univariate analysis identified lymphatic invasion, WPOI, and BD model, whereas multivariate analysis identified WPOI, as predictive factors for DFS.

Conclusion

The pathological invasion patterns should be considered when determining the follow‐up plan for patients with clinical N0 early oral tongue carcinoma.
Retinoic acid and/or progesterone differentiate mouse induced pluripotent stem cells into male germ cells in vitro
Authors: Mahabadi Javad Amini , Tameh Abolfazl Aazami , Talaei Sayyed Alireza , Karimian Mohammad , Rahiminia Tahereh , Enderami Seyed Ehsan , Gheibi Hayat Seyed Mohammad , Nikzad Hossein
Published: October 2019

Numerous reagents were employed for differentiating induced pluripotent stem cells (iPSCs) into male germ cells; however, the induction procedure was ineffective. The aim of this study was to improve the in vitro differentiation of mice iPSCs (miPSCs) into male germ cells with retinoic acid (RA) and progesterone (P). miPSCs were differentiated to embryoid bodies (EBs) in suspension with RA with or without progesterone for 0, 4, and 7 days. Then, the expression of certain genes at different stages of male germ cell development including Ddx4 (pre meiosis), Stra8 (meiosis), AKAP3 (post meiosis), and Mvh protein was examined in RNA and/or protein levels by real‐time polymerase chain reaction or flow cytometry, respectively. The Stra8 gene expression increased in the RA groups on all days. But, expression of this gene declined in RA + P groups. In addition, an increased expression of Ddx4 gene was observed on day 0 in the P group. Also, a significant upregulation was observed in the expression of AKAP3 gene in the RA + P group on days 0 and 4. However, gene expression decreased in P and RA groups on day 7. The expression of Mvh protein significantly increased in the RA group on day 7. The Mvh expression was also enhanced in the P group on day 4, but it decreased on day 7, while this protein upregulated on day 0 and 7 in the RA + P group. The miPSCs have the capacity for in vitro differentiation into male germ cells by RA and/or progesterone. However, the effects of these inducers depend on the type of combination and an effective time.
Pseudodiagonalization‐based wavefunction optimization with contracted planewave basis functions
Authors: Stuart Duncan W. , Mosey Nicholas J.
Published: October 2019

Electronic structure calculations representing the molecular orbitals (MOs) with contracted planewave basis functions (CPWBFs) have been reported recently. CPWBFs are Fourier‐series representations of atom‐centered basis functions. The mathematical features of CPWBFs permit the construction of matrix–vector products,
FC
o, involving the application of the Fock matrix, F, to the set of occupied MOs,
C
o, without the explicit evaluation of F. This approach offers a theoretical speed‐up of M/n over F‐based methods, where M and n are the number of basis functions and occupied MOs, respectively. The present study reports methodological advances that permit
FC
o‐based optimization of wavefunction formed from CPWBFs. In particular, a technique is reported for optimizing wavefunctions by combining pseudodiagonalization techniques based on an exact representation of
FC
o, approximate information regarding the virtual orbital energies, and direct inversion of the iterative subspace optimization schemes to guide the wavefunction to a converged solution. This method is found to speed‐up wavefunction optimizations by factors of up to ~6 − 8 over F‐based optimization methods while providing identical results. Further, the computational cost of this technique is relatively insensitive to basis set size, thus providing further benefits in calculations using large CPWBF basis sets. The results of density functional theory calculations show that this method permits the use of hybrid exchange‐correlation (XC) functionals with a small increase in effort over analogous calculations using generalized gradient approximation XC functionals. © 2019 Wiley Periodicals, Inc.
Smoothed Spherical Truncation based on Fuzzy Membership Functions: Application to the Molecular Encoding
Authors: García‐Jacas César R. , Marrero‐Ponce Yovani , Brizuela Carlos A. , Suárez‐Lezcano José , Martinez‐Rios Felix
Published: October 2019

A novel spherical truncation method, based on fuzzy membership functions, is introduced to truncate interatomic (or interaminoacid) relations according to smoothing values computed from fuzzy membership degrees. In this method, the molecules are circumscribed into a sphere, so that the geometric centers of the molecules are the centers of the spheres. The fuzzy membership degree of each atom (or aminoacid) is computed from its distance with respect to the geometric center of the molecule, by using a fuzzy membership function. So, the smoothing value to be applied in the truncation of a relation (or interaction) is computed by averaging the fuzzy membership degrees of the atoms (or aminoacids) involved in the relation. This truncation method is rather different from the existing ones, at considering the geometric center for the whole molecule and not only for atom‐groups, as well as for using fuzzy membership functions to compute the smoothing values. A variability study on a set comprised of 20,469 compounds (15,050 drug‐like compounds, 2994 drugs approved, 880 natural products from African sources, and 1545 plant‐derived natural compounds exhibiting anti‐cancerous activity) demonstrated that the truncation method proposed allows to determine molecular encodings with better ability for discriminating among structurally different molecules than the encodings obtained without applying truncation or applying non‐fuzzy truncation functions. Moreover, a principal component analysis revealed that orthogonal chemical information of the molecules is encoded by using the method proposed. Lastly, a modeling study proved that the truncation method improves the modeling ability of existing geometric molecular descriptors, at allowing to develop more robust models than the ones built only using non‐truncated descriptors. In this sense, a comparison and statistical assessment were performed on eight chemical datasets. As a result, the models based on the truncated molecular encodings yielded statistically better results than 12 procedures considered from the literature. It can thus be stated that the proposed truncation method is a relevant strategy for obtaining better molecular encodings, which will be ultimately useful in enhancing the modeling ability of existing encodings both on small‐to‐medium size molecules and biomacromolecules. © 2019 Wiley Periodicals, Inc.
The correlation of long non‐coding RNA intersectin 1‐2 with disease risk, disease severity, inflammation, and prognosis of acute ischemic stroke
Authors: Zhang Yi , Niu Chenglin
Published: October 2019

Background

This study aimed to evaluate the predictive value of long non‐coding RNA intersectin 1‐2 (lnc‐ITSN1‐2) for acute ischemic stroke (AIS) risk, and investigate its correlation with disease severity, inflammation, and recurrence‐free survival (RFS) in AIS patients.

Methods

Three hundred and twenty AIS patients were recruited, and plasma samples were collected within 24 hours after admission. lnc‐ITSN1‐2 expression form plasma was detected by reverse transcription‐quantitative polymerase chain reaction (RT‐qPCR). The National Institute of Health Stroke Scale (NIHSS) score was assessed, and RFS was calculated. Meanwhile, 320 controls were enrolled and plasma samples were collected on the enrollment, and lnc‐ITSN1‐2 expression was detected by RT‐qPCR.

Results

lnc‐ITSN1‐2 expression was increased in AIS patients compared to controls (P < .001), and receiver operating characteristic curve revealed its predictive value for AIS risk (area under the curve: 0.804, 95% confidence interval, 0.763‐0.845). In AIS patients, lnc‐ITSN1‐2 expression was positively correlated with NIHSS score (r = 0.464, P < .001). For inflammation, lnc‐ITSN1‐2 expression was positively correlated with CRP (r = 0.398, P < .001), TNF‐α (r = 0.502, P < .001), IL‐1β (r = 0.313, P < .001), IL‐6 (r = 0.207, P < .001), IL‐8 (r = 0.400, P < .001), IL‐17 (r = 0.272, P < .001), and IL‐22 (r = 0.222, P < .001). In terms of predicted target microRNAs, lnc‐ITSN1‐2 expression was negatively correlated with microRNA (miR)‐107 (r = −0.467, P < .001), miR‐125a (r = −0.494, P < .001), and miR‐146a (r = −0.126, P = .025). For prognosis, high lnc‐ITSN1‐2 expression was correlated with worse RFS in AIS patients.

Conclusion

lnc‐ITSN1‐2 exerts a good predictive value for AIS risk; meanwhile, its increased expression is correlated with enhanced disease severity, elevated inflammation, and worse RFS in AIS patients.
Editorial for “Dual‐Frequency MR Elastography to Differentiate Between Inflammation and Fibrosis of the Liver: Comparison With Histopathology”
Authors: Runge Jurgen Henk
Published: October 2019

Level of Evidence: 5

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2020;51:1594–1595.
Detection of sunn pest‐damaged wheat grains using artificial bee colony optimization‐based artificial intelligence techniques
Authors: Sabanci Kadir
Published: October 2019

BACKGROUND

In this study, artificial intelligence models that identify sunn pest‐damaged wheat grains (SDG) and healthy wheat grains (HWG) are presented. Svevo durum wheat cultivated in Konya province, Turkey is used for the process, with 150 HWG and 150 SDG being used for classification. Thanks to the constructed imaging setup, photos of the 300 wheat grains are obtained. Seventeen visual features of each wheat grain are extracted by image‐processing techniques and evaluated in three different groups of dimension, texture and pattern as visual parameters. Artificial bee colony (ABC) optimization‐based artificial neural network (ANN) and extreme learning machine (ELM) algorithms are implemented to classify the damaged wheat grains.

RESULTS

A correlation‐based feature selection (CFS) technique is also utilized to find the most effective among the 17 features. In the classification process using five selected features, the mean absolute error (MAE) and root mean square error (RMSE) values for ABC‐based ANN are calculated as 0.00174 and 0.00433 respectively. The proposed technique is integrated into graphical user interface (GUI) software to construct an effective detection system for practical use.

CONCLUSION

The results indicate that, thanks to the modified ANN algorithm and implemented CFS algorithm, the detection accuracy of damaged wheat grains is considerably increased. © 2019 Society of Chemical Industry
Traceability of ‘Mozzarella di Bufala Campana’ production chain by means of carbon, nitrogen and oxygen stable isotope ratios
Authors: Altieri Simona , Saiano Katya , Biondi Mariaida , Ricci Paola , Lubritto Carmine
Published: October 2019

BACKGROUND

New techniques are required to guarantee the authenticity of food, especially for PDO (Protected Designation of Origin) trademarks. The genuineness of a product is directly related to the raw material and to the production process used. In this article, the traceability of the Mozzarella di Bufala Campana PDO was investigated, using carbon, nitrogen and oxygen stable isotopes ratios, measured on buffalo feeding, milk and mozzarella, from Caserta and Salerno farms. Furthermore, 37 mozzarella brands were analyzed (carbon, nitrogen and oxygen isotopes) from the different production areas, to characterize their origin.

RESULTS

The results of this work showed no changes in carbon and nitrogen isotopic ratios of milk and mozzarella, indicating no fractionation in the production process. The δ13C of milk was influenced by feeding signal; while, milk δ15N was regulated by fractionation occurring during ruminant metabolism. Mozzarella oxygen isotopic signal depleted with respect to the milk one.

Regarding brand samples, it was found that the geographical differentiation is based more on carbon isotopes than on the nitrogen and oxygen ones.

CONCLUSION

This work gives an important contribution to the knowledge regarding the traceability of such a particular cheese as mozzarella. © 2019 Society of Chemical Industry
Natural occurrence of Alternaria mycotoxins in malting barley grains in the main producing region of Argentina
Authors: Castañares Eliana , Pavicich Maria A , Dinolfo Maria I , Moreyra Federico , Stenglein Sebastián A , Patriarca Andrea
Published: October 2019

BACKGROUND

Barley (Hordeum vulgare L.) is one of the most important cereals worldwide, and its quality is affected by fungal contamination such as species of the genus Alternaria. No information is available about the occurrence of Alternaria mycotoxins in Argentinean barley grains, which is of concern, because they can be transferred into malt and beer. The aim of this study was to analyze the occurrence of alternariol (AOH), alternariol monomethyl ether (AME) and tenuazonic acid (TeA) in malting barley grains from the main producing region of Argentina during the 2014 and 2015 growing seasons.

RESULTS

The most frequent mycotoxin was AOH (64%), which was detected at higher levels (712 μg kg−1) compared with other studies, followed by TeA (37%, 1522 μg kg−1), while AME was present in five samples in the 2015 growing season only, with a mean of 4876 μg kg−1. A similar frequency of mycotoxin occurrence was observed in both years (80.8 vs 85.3%), but more diverse contamination was found in 2015, which was characterized by lower accumulated precipitation. Nevertheless, AOH was more frequently found in 2014 than in 2015 (80.8 and 47.1% respectively). A negative correlation between AOH concentration and temperature was observed. The susceptibility of different barley varieties to mycotoxin accumulation varied with the mycotoxin, geographical location and meteorological conditions.

CONCLUSION

The results obtained in the present work represent a tool for risk assessment of exposition to these mycotoxins and could be used by food safety authorities to determine the need for their regulation. Furthermore, the establishment of a hazard analysis and critical control point (HACCP) system to minimize fungal and mycotoxin contamination in barley from farm to processing could be apply to ensure food safety. © 2019 Society of Chemical Industry
Complex Posttraumatic Stress Disorder Symptom Profiles in Traumatized Refugees
Authors: Liddell Belinda J. , Nickerson Angela , Felmingham Kim L. , Malhi Gin S. , Cheung Jessica , Den Miriam , Askovic Mirjana , Coello Mariano , Aroche Jorge , Bryant Richard A.
Published: October 2019

Although it is well documented that exposure to severe, cumulative trauma and postdisplacement stress increases the risk for posttraumatic stress symptom disorder (PTSD), less is known about the representation and predictors of complex PTSD (CPTSD) symptoms in refugee populations. We examined PTSD and CPTSD symptom profiles (co‐occurring PTSD and disturbances in self‐organization [DSO] symptoms) and their premigration, postmigration, and demographic predictors, using latent class analysis (LCA), in a cohort of 112 refugees resettled in Australia. The LCA identified a four‐factor model as the best fit to the data, comprising classes categorized as: (a) CPTSD, exhibiting high levels of PTSD and DSO symptoms (29.5%); (b) PTSD only (23.5%); (c) high affective dysregulation (AD) symptoms (31.9%); and (d) low PTSD and DSO symptoms (15.1%). Membership in the CPTSD and PTSD classes was specifically associated with cumulative traumatization, CPTSD OR = 1.56, 95% CI [1.15, 2.12], and PTSD OR = 1.64, 95% CI [1.15, 2.34]; and female gender, CPTSD OR = 14.18, 95% CI [1.66, 121.29], and PTSD OR = 16.84, 95% CI [1.78, 159.2], relative to the low‐symptom class. Moreover, CPTSD and AD class membership was significantly predicted by insecure visa status, CPTSD OR = 7.53, 95% CI [1.26, 45.08], and AD OR = 7.19, 95% CI [1.23, 42.05]. These findings are consistent with the ICD‐11 model of CPTSD and highlight the contributions of cumulative trauma to CPTSD and PTSD profiles as well as of contextual stress from visa uncertainty to DSO symptom profiles in refugee cohorts, particularly those characterized by AD.
Taxon‐specific dark survival of diatoms and flagellates affects Arctic phytoplankton composition during the polar night and early spring
Authors: van de Poll Willem H. , Abdullah Edwin , Visser Ronald J. W. , Fischer Philipp , Buma Anita G. J.
Published: October 2019

Effects of prolonged darkness on Arctic phytoplankton composition were investigated with lab experiments and a pigment time series in Kongsfjorden, Spitsbergen (78°55′N). Chlorophyll a (Chl a), pigment composition, particulate organic carbon, cell numbers, and photosynthetic characteristics were studied in Arctic diatoms (Thalassiosira antarctica, Thalassiosira nordenskioeldii) and flagellates (Rhodomonas sp., Micromonas sp.) during 8 weeks of darkness and subsequent recovery in irradiance. Loss of photosynthetic functionality after 2 weeks of darkness was reversible in all species when returned to irradiance. Diatoms were more resistant to prolonged darkness (> 2 weeks) compared to the flagellates, with lower decline rates of Chl a and maximum quantum yield of PSII. T. nordenskioeldii showed rapid growth during recovery throughout 8 weeks of dark incubation, whereas recovery of flagellates diminished within 4 weeks. Ratios of taxonomic marker pigments relative to Chl a of all species showed limited variation during 8 weeks of dark incubation. The experimentally observed enhanced dark survival of diatoms was in agreement with pigment observations during four polar nights (2013–2017) in Kongsfjorden, which showed increased relative diatom abundance during declining biomass (down to 0.02 mg Chl a m−3). Therefore, a period of prolonged darkness gives Arctic diatoms a head start during the early stages of the spring bloom. The taxon‐specific survival traits can influence the geographical distribution of diatoms and flagellates within the polar oceans and their phenology. Furthermore, the persistence of Chl a of nonviable phytoplankton during darkness might influence biomass estimates during the polar night.
Frame properties of operator orbits
Authors: Christensen Ole , Hasannasab Marzieh , Philipp Friedrich
Published: October 2019

We consider sequences in a Hilbert space of the form , with a linear operator T, the index set being either or , a vector , and answer the following two related questions: (a) Which frames for are of this form with an at least closable operator T? and (b) For which bounded operators T and vectors f0 is a frame for ? As a consequence of our results, it turns out that an overcomplete Gabor or wavelet frame can never be written in the form with a bounded operator T. The corresponding problem for remains open. Despite the negative result for Gabor and wavelet frames, the results demonstrate that the class of frames that can be represented in the form with a bounded operator T is significantly larger than what could be expected from the examples known so far.
OSuvm: An interactive online consensus survival tool for uveal melanoma prognosis analysis
Authors: Wang Fengling , Wang Qiang , Li Ning , Ge Linna , Yang Mengsi , An Yang , Zhang Guosen , Dong Huan , Ji Shaoping , Zhu Wan , Guo Xiangqian
Published: October 2019

Uveal melanoma (UM) is a rare, aggressive, but the most frequent primary intraocular malignancy in adults, and up to 50% of patients develop a tendency of liver metastases. Great efforts have been made to develop biomarkers that facilitate diagnosis, prediction of the risk, and response to treatment of UM. However, a biologically informative and highly accurate gold standard system for prognostic evaluation of UM remains to be established. To facilitate assessment of the prognosis of UM patients, we established a user‐friendly Online consensus Survival tool for uveal melanoma, named OSuvm, by which users can easily estimate the prognostic values of genes of interest by the Kaplan‐Meier survival plot with hazard ratio and log‐rank test. OSuvm comprises four independent cohorts including 229 patients with both gene expression profiles and relevant clinical follow‐up information, and it has shown great performance in evaluating the prognostic roles of previously reported biomarkers. Using OSuvm enables researchers and clinicians to rapidly and conveniently explore the prognostic value of genes of interest and develop new potential molecular biomarkers for UM. OSuvm can be accessed at http://bioinfo.henu.edu.cn/UVM/UVMList.jsp.
Space‐time finite element adaptive AMG for multi‐term time fractional advection diffusion equations
Authors: Yue Xiaoqiang , Liu Menghuan , Shu Shi , Bu Weiping , Xu Yehong
Published: October 2019

In this study, we construct a space‐time finite element (FE) scheme and furnish cost‐efficient approximations for one‐dimensional multi‐term time fractional advection diffusion equations on a bounded domain Ω. Firstly, a fully discrete scheme is obtained by the linear FE method in both temporal and spatial directions, and many characterizations on the resulting matrix are established. Secondly, the associated condition number estimation
is derived, where τn and h, respectively, are the current time and space step sizes. Next, we propose a lossless in robustness and adaptive algebraic multigrid (AMG) with
computational cost and
matrix‐free storage, in contrast to classical AMG with
, where M is the number of spatial segments. Meanwhile, uniform convergence analyses on the two‐level V(0,1)‐cycle of classical and adaptive AMGs are provided. Finally, we demonstrate the optimal error order of space‐time FE approximations in the L2(Ω) norm sense, present theoretical confirmations and predictable behaviors of the proposed algorithm in numerical experiments.
A compact triple‐mode bandpass filter with wide‐stopband using half‐mode substrate integrated waveguide cavity loaded with slots
Authors: Liu Baoguang , Lyu Yun‐Peng , Zhu Lei , Cheng Chonghu
Published: October 2019

In this article, a new compact triple‐mode filter with wide stopband is proposed on half‐mode substrate integrated waveguide (HMSIW) with loaded slots. The loaded slots not only make the TE201 mode shift toward the TE101 mode, but also introduce an extra resonant mode to achieve a compact triple‐mode filter. In addition, the wide stopband is realized because the TE202 mode keeps nearly unchanged as the TE201 mode decreases to a much lower frequency by virtue of loaded slots. The working principle and design method are given in this context. All these triple resonant modes can be controlled as required. To verify the design concept, a prototype with only 0.23λg2 area is designed and the upper stopband can be extended to 1.87f0 with rejection level of 25 dB.
A strong formulation for the graph partition problem
Authors: Chopra Sunil , Shim Sangho
Published: October 2019

We develop a polynomial size extended graph formulation of the graph partition problem which dominates the formulation introduced by Chopra and Rao's study, and show that the extended graph formulation is tight on a tree. We introduce exponentially many valid inequalities to the Chopra‐Rao formulation, which we call generalized arc inequalities (GAI), and develop a linear time algorithm to separate the most violated generalized arc inequality. We show that the polynomial size extended graph formulation is equivalent to the Chopra‐Rao formulation augmented by the exponentially many GAI.
Enhancing stratigraphic, structural and dissolution features in GPR images of carbonate karst through data processing
Authors: de Oliveira Josibel Gomes , de Medeiros Walter Eugenio , de Santana Flávio Lemos , Bezerra Francisco Hilário Rego , Cazarin Caroline Lessio
Published: October 2019

Obtaining high‐quality ground penetrating radar (GPR) images in karst is difficult because materials resulting from the weathering of carbonate rocks might be electrically conductive. As a consequence, penetration depth and signal resolution might be greatly reduced due to attenuation. In addition, fractures and faults might cause a significant amount of electromagnetic wave scattering. We present a 2D data processing flow which allows improving the quality of GPR images in carbonate karst. The processing flow is composed of the following steps: obtaining a zero‐offset section by removing the direct wave, low‐frequency noise removal, geometrical spreading and exponential gain compensation, spectral balancing, Kirchhoff migration, bandpass filtering, amplitude‐volume enhancement, and topographic correction. For a 200‐MHz dataset, we present in detail each step of the processing flow, exemplifying how to parameterize every step. Spectral balancing is of key importance because it can approximately replenish the high‐frequency content lost due to propagation effects. In this step, we recommend to shift the centroid frequency as much as possible to high‐frequency values, even exceeding the nominal value of the antenna center frequency, but still looking for a band‐limited spectrum as the goal. Despite the difficulty of migrating GPR data, we show that migration (even assuming a constant velocity) might enhance the lateral continuity of the reflection events and allows identification of discontinuities such as faults and fractures. If imaged in a better way, these structures can have special importance as they are often the boundaries of dissolution features. Obtaining images based on amplitude‐volume enhancement techniques allows to better visualize karst voids and deep‐rooted discontinuities because these features are often associated with low‐amplitude zones, which are highlighted in such images. Due to this processing flow, stratigraphic, structural and dissolution features can be enhanced, allowing the interpreter to establish spatial and genetic associations among these elements to obtain a better understanding of the karst formation process.
Experimental study on filling imbalance of plastic parts with microcylinders
Authors: Xu Bin , Deng Ailin , Xue Song
Published: October 2019

To examine the microscale filling imbalance in the present work, an eight‐cavity injecting mold with microcylindrical‐hole arrays fabricated by micro‐electrical discharge machining milling technology was developed. Polypropylene (PP) was used to carry out single factor filling flow experiments with vacuuming the mold cavities. The filling height difference of micro cylindrical hole at the same position between cavity I and cavity II, which was the index of filling imbalance and the effect of mold temperature and injection rate on the filling imbalance of microholes with diameters of 200 μm and 300 μm was investigated. The results revealed that the maximum height difference reached 101 μm with low process parameters, and the filling imbalance was obvious. With the increase in mold temperature and injection rate, the filling imbalance was weakened. In addition, the impact of the scale effect on filling imbalance was checked. The filling imbalance of micro holes in 200 μm was greater than that in 300 μm using identical process parameters. With the increase in mold temperature and injection rate, the filling height difference of the two kinds of micro holes decreased. POLYM. ENG. SCI., 60:22–31, 2020. © 2019 Society of Plastics Engineers
Low On‐Resistance and Low Trapping Effects in 1200 V Superlattice GaN‐on‐Silicon Heterostructures
Authors: Kabouche Riad , Abid Idriss , Püsche Roland , Derluyn Joff , Degroote Stefan , Germain Marianne , Tajalli Alaleh , Meneghini Matteo , Meneghesso Gaudenzio , Medjdoub Farid
Published: October 2019

Herein, the development of gallium nitride on silicon (GaN‐on‐Si) heterostructures targeting 1200 V power applications is reported. In particular, it is shown that the insertion of superlattices (SLs) into the buffer layers allows pushing the vertical breakdown voltage above 1200 V without generating additional trapping effects as compared with a more standard optimized step‐graded AlGaN‐based epistructure using a similar total buffer thickness. DC characterizations of fabricated transistors by means of back‐gating measurements reflect both the enhancement of the breakdown voltage and the low trapping effects up to 1200 V. These results show that a proper buffer optimization and the insertion of SL pave the way to GaN‐on‐Si lateral power transistors operating at 1200 V with low on‐resistance and low trapping effects.
Temperature‐Dependent Polarized Photoluminescence from c‐plane InGaN/GaN Multiple Quantum Wells Grown on Stripe‐Shaped Cavity‐Engineered Sapphire Substrate
Authors: Kim Jongmyeong , Park Seoung-Hwan , Ahn Doyeol , Yoon Euijoon
Published: October 2019

Temperature‐dependent polarized photoluminescence from anisotropically strained c‐plane InGaN/GaN multiple quantum wells on stripe‐shaped cavity‐engineered sapphire substrate is theoretically and experimentally investigated. Polarization ratios decrease from 0.98 to 0.74, and emission peak shifts increase from 0 to 50.9 meV with increasing temperature from 10 to 300 K, respectively. Theoretical calculations based on k·p perturbation theory reveal that the temperature dependence of polarized optical behaviors is attributed to the modified valence band structures and hole distributions in each subband. Theoretical results are in good agreement with the experimental results over temperature range from 10 to 300 K, providing in‐depth understanding for the strain‐induced valence band modification of III‐nitride semiconductors.
First principle investigation of the thermomechanical properties of type A carbonated apatite
Authors: Ulian Gianfranco , Valdrè Giovanni
Published: October 2019

Calcium apatites with the general chemical formula (Ca, X)10(PO4, Y)6Z2 represent a mineral family of utmost importance in several fields, for example, bone biology, biomaterials, and mineralogy. However, few works have focused on the mechanical properties of these phases, and in particular, no data are available on the thermomechanical and thermodynamic properties of carbonate‐bearing (hydroxyl)apatites. In the present work, the equation of state of type A carbonated apatite (CAp, Ca10(PO4)6CO3, space group P1) was calculated by ab initio quantum mechanical methods within the density functional theory (DFT) framework. Starting from athermal results (at 0 K), the combined effect of temperature and pressure was investigated through the quasiharmonic approximation (QHA). In athermal conditions, the equation of state of the CAp unit cell volume can be described by a third‐order Birch‐Murnaghan formulation, with parameters V0 = 538.14(5) Å3, K0 = 106.2(7) GPa, and K′ = 4.6(4). The QHA well described the temperature and pressure dependence of the thermodynamics and mechanical properties of the mineral. For instance, the bulk modulus at 0 GPa and ambient temperature (300 K) is K
T0 = 102.95 GPa, which is lower than that of stoichiometric apatite by about 6%. The unit cell thermal expansion coefficient between 0 and 600 K was also calculated and reported. The results are in line with the few available experimental data reported in literature on type AB carbonated hydroxylapatite. The reported findings further extend the knowledge of the mechanical and thermal behaviors of this important mineral found in biological environments, results that are useful for biotechnological and other applications of the (C)OHAp phases.
An extended mixed‐effects framework for meta‐analysis
Authors: Sera Francesco , Armstrong Benedict , Blangiardo Marta , Gasparrini Antonio
Published: October 2019

Standard methods for meta‐analysis are limited to pooling tasks in which a single effect size is estimated from a set of independent studies. However, this setting can be too restrictive for modern meta‐analytical applications. In this contribution, we illustrate a general framework for meta‐analysis based on linear mixed‐effects models, where potentially complex patterns of effect sizes are modeled through an extended and flexible structure of fixed and random terms. This definition includes, as special cases, a variety of meta‐analytical models that have been separately proposed in the literature, such as multivariate, network, multilevel, dose‐response, and longitudinal meta‐analysis and meta‐regression. The availability of a unified framework for meta‐analysis, complemented with the implementation in a freely available and fully documented software, will provide researchers with a flexible tool for addressing nonstandard pooling problems.
Nonparametric estimation of the cumulative incidence function under outcome misclassification using external validation data
Authors: Edwards Jessie K. , Bakoyannis Giorgos , Yiannoutsos Constantin T. , Mburu Margaret W. , Cole Stephen R.
Published: October 2019

Misclassification of outcomes or event types is common in health sciences research and can lead to serious bias when estimating the cumulative incidence functions in settings with competing risks. Recent work has shown how to estimate nonparametric cumulative incidence functions in the presence of nondifferential outcome misclassification when the misclassification probabilities are known. Here, we extend this approach to account for misclassification that is differential with respect to important predictors of the outcome using misclassification probabilities estimated from external validation data. Moreover, we propose a bootstrap approach in which the observations from both the main study data and the external validation study are resampled to allow the uncertainty in the misclassification probabilities to propagate through the analysis into the final confidence intervals, ensuring appropriate confidence interval coverage probabilities. The proposed estimator is shown to be uniformly consistent and simulation studies indicate that both the estimator and the standard error estimation approach perform well in finite samples. The methodology is applied to estimate the cumulative incidence of death and disengagement from HIV care in a large cohort of HIV infected individuals in sub‐Saharan Africa, where a significant death underreporting issue leads to outcome misclassification. This analysis uses external validation data from a separate study conducted in the same country.
Highly Efficient Electroreduction of CO2 on Nickel Single‐Atom Catalysts: Atom Trapping and Nitrogen Anchoring
Authors: Mou Kaiwen , Chen Zhipeng , Zhang Xinxin , Jiao Mingyang , Zhang Xiangping , Ge Xin , Zhang Wei , Liu Licheng
Published: October 2019

Construction of single atom catalysts (SACs) with high activity toward electroreduction of CO2 still remains a great challenge. A very simple and truly cost‐effective synthetic strategy is proposed to prepare SACs via a impregnation–pyrolysis method, through one‐step pyrolysis of graphene oxide aerogel. Compared with other traditional methods, this process is fast and free of repeated acid etching, and thus it has great potential for facile operation and large‐scale manufacturing. Both X‐ray absorption fine structure and high‐angle annular dark‐field scanning transmission electron microscopy images confirm the presence of isolated nickel atoms, with a high Ni loading of ≈2.6 wt%. The obtained 3D porous Ni‐ and N‐codoped graphene aerogel exhibits excellent activity toward electroreduction of CO2 to CO, in particular exhibiting a remarkable CO Faradaic efficiency of 90.2%. Density functional theory calculations reveal that free energies for the formation of intermediate *COOH on coordinatively unsaturated NiN sites are significantly lower than that on NiN4 site, suggesting the outstanding activities of CO2 electroreduction originate from coordinatively unsaturated NiN sites in catalysts.
Flexible 3D Porous MXene Foam for High‐Performance Lithium‐Ion Batteries
Authors: Zhao Qian , Zhu Qizhen , Miao Jiawei , Zhang Peng , Wan Pengbo , He Lingzhang , Xu Bin
Published: October 2019

2D transition‐metal carbides and nitrides, named MXenes, are promising materials for energy storage, but suffer from aggregation and restacking of the 2D nanosheets, which limits their electrochemical performance. In order to overcome this problem and realize the full potential of MXene nanosheets, a 3D MXene foam with developed porous structure is established via a simple sulfur‐template method, which is freestanding, flexible, and highly conductive, and can be directly used as the electrode in lithium‐ion batteries. The 3D porous architecture of the MXene foam offers massive active sites to enhance the lithium storage capacity. Moreover, its foam structure facilitates electrolyte infiltration for fast Li+ transfer. As a result, this flexible 3D porous MXene foam exhibits significantly enhanced capacity of 455.5 mAh g−1 at 50 mA g−1, excellent rate performance (101 mAh g−1 at 18 A g−1), and superior ultralong‐term cycle stability (220 mAh g−1 at 1 A g−1 after 3500 cycles). This work not only demonstrates the great superiority of the 3D porous MXene foam but also proposes the sulfur‐template method for controllable constructing of the 3D foam from 2D nanosheets at a relatively low temperature.
Downsizing weight while upsizing efficiency: An experimental approach to develop optimized ultra‐light UHPC hybrid beams
Authors: Gaganelis Georgios , Mark Peter
Published: October 2019

A three‐phase topology optimization is applied to a conventional reinforced concrete (RC) beam loaded in four‐point bending. The aim is to reduce material amounts to a minimum while preserving load bearing capacity and stiffness. The optimization result is converted into two alternative designs, namely a RC truss structure and a hybrid concrete‐steel (HCS) truss structure. The RC truss structure is constructed in conventional reinforced concrete. By contrast, the HCS truss structure is designed using ultra‐high performance fiber‐reinforced concrete (UHPFRC) and S355 structural steel. Experimental studies demonstrate a 53% reduction in weight of the RC truss structure compared to the reference beam, while achieving a similar load bearing capacity and a significantly higher stiffness, albeit by increasing the structure's height. For the HCS truss structure, the weight saving is considerably higher, namely 83%, whereas the load bearing capacity can be increased by 10%. The stiffness remains comparable to that of the RC truss structure by increasing the structure's height likewise, while a more ductile type of failure is achieved.