bluuebunny/crossref_metadata_2025_split huggingface dataset:
Few‐shot learning with deformable convolution for multiscale lesion detection in mammography
Authors: Li Ce , Zhang Dong , Tian Zhiqiang , Du Shaoyi , Qu Yanyun 
Published: March 2020

PurposeImage‐based breast lesion detection is a powerful clinical diagnosis technology. In recent years, deep learning architectures have achieved considerable success in medical image analysis however, they always require large‐scale samples. In mammography images, breast lesions are inconspicuous, multiscale, and have blurred edges. Moreover, few well‐labeled images exist. Because of these factors, the detection accuracy of conventional deep learning methods is low. Therefore, we attempted to improve the accuracy of mammary lesion detection by introducing transfer learning (TL) into a deep learning framework for the few‐shot learning task and thus provide a method that will further assist physicians in detecting breast lesions.MethodsIn this paper, we propose a method called “few‐shot learning with deformable convolution for multiscale lesion detection in mammography,” named FDMNet. Deformable convolution is introduced for enhancing the network’s ability to detect lesions, and the sensitivity of the multiscale feature space is reinforced by using a feature pyramid method. Furthermore, by introducing location information in the predictor, the sensitivity of the model to lesion location is also enhanced. The proposed method, through the TL technique that is applied mines the potentially common knowledge of features in the source domain and transfers it into the target domain to improve the accuracy of breast lesion detection in the few‐shot learning task.ResultsOn the publicly available datasets for screening mammography CBIS‐DDSM and Mini‐MIAS, the proposed method performs better than five widely used detection methods. On the CBIS‐DDSM dataset, its comprehensive scores, sensitivity, precision, and the mean dice similarity coefficient are 0.911, 0.949, 0.873, and 0.913, respectively, and on the Mini‐MIAS dataset, these values are 0.931, 0.966, 0.882, and 0.941, respectively.ConclusionsTo achieve the few‐shot learning required for medical image analysis, the proposed method uses TL to execute feature knowledge transformation and includes deformable convolution to build a feature pyramid structure, which enhances the learning performance of the network for lesions. The results of comparative numerical experiments show that the proposed method outperforms some state‐of‐the‐art methods.
Joint‐aggregation intumescent flame‐retardant effect of ammonium polyphosphate and charring agent in polypropylene
Authors: Tang Wei , Qian Lijun , Chen Yajun , Qiu Yong , Xu Bo , Li Juan 
Published: March 2020

AbstractIn order to explore the structure mode of intumescent flame retardants (IFRs) with higher efficiency, IFR particles with joint‐aggregation structure (@IFR) were obtained through the treatment of ammonium polyphosphate (APP) and a charring agent (PT‐Cluster) in their aqueous solution. Then, the joint‐aggregation IFR effect was researched using its application in polypropylene. In case of 20 wt% IFR loading, the limiting oxygen index (LOI) value of @IFR/PP was 1.1% higher than that of 15APP/5PT‐Cluster/PP mixture, and a 1.6 mm‐thick @IFR/PP composite passed the UL 94 V‐2 rating test, while 15APP/5PT‐Cluster/PP demonstrated no flame‐retardant rating in UL 94 vertical burning tests. In a cone calorimeter test, @IFR also had a better inhibition effect on heat release. The average heat release rate (av‐HRR) value during 0 to 120 seconds of @IFR/PP was only 41 kW m−2, which was 33.9% lower than that of the 15APP/5PT‐Cluster/PP. Furthermore, the peak heat release rate (pk‐HRR) of @IFR/PP was 20.5% lower than that of 15APP/5PT‐Cluster/PP, and the time to pk‐HRR of @IFR/PP was 710 seconds, while that of 15APP/5PT‐Cluster/PP was 580 seconds. The better inhibition effect on HRR and the delay of time to pk‐HRR were caused by the joint‐aggregated structure of @IFR, which can rapidly react to form stable and efficient char layers. This kind of join‐aggregation IFR effect has great significance in suppressing the spread of fire in reality. In addition, @IFR also increased the mechanical properties of PP composites slightly compared with the APP/PT‐Cluster mixture.
Addressing implicit bias in pediatric hematology‐oncology
Authors: Tsai Jessica W. , Kesselheim Jennifer C. 
Published: March 2020

AbstractAlthough awareness of implicit bias and its influence on providers and patients is increasing, the effects of implicit bias on the field of pediatric hematology‐oncology are less clear. This Special Report reviews the literature on implicit bias in pediatrics and medical oncology and further provides case examples and suggestions on what can be done to address implicit bias. There is a need for further research on how implicit bias impacts the complex care of pediatric hematology‐oncology patients.
Novel electrospun polymer electrolytes incorporated with Keggin‐type hetero polyoxometalate fillers as solvent‐free electrolytes for lithium ion batteries
Authors: Banitaba Seyedeh Nooshin , Semnani Dariush , Heydari‐Soureshjani Elahe , Rezaei Behzad , Ensafi Ali A , Taghipour‐Jahromi Ahmadreza 
Published: March 2020

AbstractIn this study, solvent‐free nanofibrous electrolytes were fabricated through an electrospinning method. Polyethylene oxide (PEO), lithium perchlorate and ethylene carbonate were used as polymer matrix, salt and plasticizer respectively in the electrolyte structures. Keggin‐type hetero polyoxometalate (Cu‐POM@Ru‐rGO, Ni‐POM@Ru‐rGO and Co‐POM@Ru‐rGO (POM, polyoxometalate; rGO, reduced graphene oxide)) nanoparticles were synthesized and inserted into the PEO‐based nanofibrous electrolytes. TEM and SEM analyses were carried out for further evaluation of the synthesized filler structures and the electrospun nanofibre morphologies. The fractions of free ions and crystalline phases of the as‐spun electrolytes were estimated by obtaining Fourier transform infrared and XRD spectra, respectively. The results showed a significant improvement in the ionic conductivity of the nanofibrous electrolytes by increasing filler concentrations. The highest ionic conductivity of 0.28 mS cm−1 was obtained by the introduction of 0.49 wt% Co‐POM@Ru‐rGO into the electrospun electrolyte at ambient temperature. Compared with solution‐cast polymeric electrolytes, the electrospun electrolytes present superior ionic conductivity. Moreover, the cycle stability of the as‐spun electrolytes was clearly improved by the addition of fillers. Furthermore, the mechanical strength was enhanced with the insertion of 0.07 wt% fillers to the electrospun electrolytes. The results implied that the prepared nanofibres are good candidates as solvent‐free electrolytes for lithium ion batteries. © 2020 Society of Chemical Industry
Fluorescence Turn‐On Analysis of Trace Protein Based on Carbon Nanodots and Hybridization Chain Reaction
Authors: Yang Dawei , Zhang Xujia , Kou Xinyue , Shao Xuejun , Miao Peng 
Published: March 2020

AbstractIn this work, an ultrasensitive method for trace protein detection based on fluorescent carbon nanodots and hybridization chain reaction (HCR) is designed. Generally, the synthesized bright carbon nanodots are conjugated with two hairpin‐structured DNA probes, respectively, which act as subsequent HCR fuel strands. Since single‐stranded parts of DNA probes could be easily absorbed on graphene oxide (GO) nanosheets, fluorescence emission of carbon nanodots is effectively quenched via fluorescence resonance energy transfer. However, in the presence of target protein, the aptamer sequence in another hairpin‐structured DNA probe specially interacts with target and the hairpin is opened. A single‐stranded region is thus exposed, which initiates HCR by coupling with the DNA fuel strands on carbon nanodots. The formed HCR product displays a rigid, long double‐stranded structure, which facilitates the release of carbon nanodots from GO surface. As a result, fluorescence of carbon nanodots is recovered and initial concentration of target protein can be estimated. This protein detection method shows a favorable linear response with a low limit of detection (2.3 fg mL−1). Furthermore, it is highly selective and capable of detecting target in biological fluids like serum samples, which demonstrates the promising applications of this method.
Nonempirical (double‐hybrid) density functionals applied to atomic excitation energies: A systematic basis set investigation
Authors: Hernández‐Martínez Laura , Brémond Eric , Pérez‐Jiménez Angel J. , San‐Fabián Emilio , Adamo Carlo , Sancho‐García Juan C. 
Published: March 2020

AbstractWe investigate here the lowest‐energy (spin‐conserving) excitation energies for the set of He‐Ne atoms, with the family of nonempirical PBE, PBE0, PBE0‐1/3, PBE0‐DH, PBE‐CIDH, PBE‐QIDH, and PBE0‐2 functionals, after employing a wide variety of basis sets systematically approaching the basis set limit: def2‐nVP(D), cc‐pVnZ, aug‐cc‐pVnZ, and d‐aug‐cc‐pVnZ. We find that an accuracy (ie, mean unsigned error) of 0.3 to 0.4 eV for time‐dependent density functional theory (DFT) atomic excitation energies can be robustly achieved with modern double‐hybrid methods, which are also stable with respect to the addition of a double set of diffuse functions, contrarily to hybrid versions, in agreement with recent findings employing sophisticated multiconfigurational DFT methods.
Facile Synthesis, Spectral (IR, Mass, UV−Vis, NMR), Linear and Nonlinear Investigation of the Novel Phosphonate Compounds: A Combined Experimental and Simulation Study
Authors: Khalid Muhammad , Ali Akbar , De la Torre Alexander F. , Marrugo Kelly P. , Concepcion Odette , Kamal Ghulam Mustafa , Muhammad Shabbir , Al‐Sehemi Abdullah G. 
Published: March 2020

AbstractHerein, we reported the imino phosphonate compounds: (4‐methoxy‐benzylidene‐amino‐phenyl‐methyl‐phosphonic acid diethyl ester (MBPDE), 4‐hydroxy‐benzylidene‐amino‐phenyl‐methyl‐phosphonic acid diethyl ester (HBPDE) and 4‐hydroxy‐3‐methoxy‐benzylidene‐amino‐phenyl‐methyl‐phosphonic acid diethyl ester (HMBPD) form the chemical reaction of diethyl (α‐amino benzyl)phosphonate hydrochloride and substituted benzaldehyde. These compounds were characterized by various spectroscopic techniques: FT‐IR, Mass, UV–VIS, 1H NMR and 13 C NMR. Additionally, the optimized molecular structures, FT‐IR, natural bond orbitals (NBOs), frontier molecular orbitals (FMOs), non‐linear optical (NLO) properties were calculated by the density functional theory (DFT) using the B3LYP functional with the 6–311+G(d,p) basis set. Moreover, UV–Visible spectrum of MBPDE, HBPDE and HMBPD were predicted in different solvents using the time dependent TD‐DFT [B3LYP/6‐311+G(d,p)] method using Polarizable Continuum Model (PCM). The non‐linear optical (NLO) properties were calculated by M06 functional with the 6–311+G(d,p) basis set. A synergistic relationship is observed between the experimental and theoretical findings. NBO analysis provided insights about the stability and charge delocalization of the entitled molecules. The global reactivity descriptors were achieved through HOMO‐LUMO energies. The efficiency of the entitled molecules concerning charge transfer and participation in diverse chemical reactivities were figured out perceptibly by applying the frontier molecular orbitals (FMOs) analysis. The average polarizability
values: 277.184, 261.332 and 280.254 a.u. of the MBPDE, HBPDE and HMBPD were determined respectively. The total first hyperpolarizability (βtot) values of the MBPDE, HBPDE and HMBPD were also obtained to be 992.900, 781.527 and 1107.526 a.u. respectively. The compound HMBPD comprising of higher magnitude of average polarizability and the total first hyperpolarizability (βtot) values than MBPDE and HBPDE molecules. Moreover, NLO properties of urea molecule were found smaller in comparison to the MBPDE, HBPDE and HMBPD. The medicinal importances of these novel compounds as well as its contribution towards nonlinear optical field are our future targets.
A Facile Formation of Vanadium(0) by the Reduction of Vanadium Pentoxide Pelletized with Magnesium Oxide Enabled by Microwave Irradiation
Authors: Inazu Naomi , Suzuki Eiichi , Fujii Satoshi , Tsubaki Shuntaro , Wada Yuji 
Published: March 2020

AbstractThe reduction of V2O5 to vanadium metal(0), that requires severe conditions in conventional reduction methods, was enabled to be proceeded in a short time of 1 h at 1273 K by the reaction with magnesium vapor with the isolation yield of V(0) in 55.6% by using microwave irradiation of 820 W. A pressurized pelletization of powdery V2O5 well‐mixed with MgO powder at a specific mixing ratio followed by calcination in ambient air at 1173 K was crucial for the reaction since a complex oxide of MgV2O4, presumably as a precursor, was formed in calcination of the V2O5/MgO pellet to be reduced to V(0) by the reaction with magnesium. Calcination of V2O5/MgO pellets with different mixing ratios or different temperatures resulted in the formation of different kinds of complex oxide of vanadium and magnesium such as α‐Mg2V2O7, Mg3(VO4)2, triclinic Mg2V2O7, and MgV2O6. While the yield of V(0) was dependent on the kind of the complex oxide, formation of MgV2O4 was essential as the precursor to the formation of V(0).
Sonogashira Coupling (Cu/Amine‐Free) of ArBr/Cl in Aerobic Condition and N‐Benzylation of Aniline with Benzyl Alcohol Catalyzed by Complexes of Pd(II) with Sulfated/Selenated NHCs
Authors: Dubey Pooja , Singh Ajai K. 
Published: March 2020

AbstractThe moisture and air insensitive, and thermally stable [Pd(L1/L2‐H)Cl][PF6] (1/2) and [Pd(L3/L4‐HI)Cl2] (3/4) catalyze N‐benzylation of aniline (at 100 °C) and Sonogashira coupling of ArBr/Cl (at 80 °C) in the presence of KOH and K2CO3 respectively. The optimum catalyst loading (mol %) is 0.02‐0.1 for the C−C coupling and 0.5 for N‐benzylation. The 1–4 were found reusable. The L1/L2=3‐(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)methyl)‐1‐(2‐(phenyl thio/seleno)ethyl)‐1H‐benzo[d]imidazol‐3‐ium hexafluorophosphate and L3/L4=4‐methyl‐1‐(2‐(phenylthio/seleno)ethyl)‐1H‐1,2,4‐triazol‐4‐ium iodide are precursors of N‐heterocyclic carbenes. Copper‐catalyzed click reaction gave L1/L2. The treatment of triazole with ClCH2CH2Cl, [PhS/Se]−Na+ and MeI successively afforded L3/L4. The sequence of reactions of L1‐L4 with Ag2O and [Pd(CH3CN)2Cl2] (M : L=1 : 1) gave 1–4. The L1‐L4 and 1–4 were characterized by elemental analyses, multi‐nuclei NMR, HR‐MS and single‐crystal structure (3 and 4). The geometry of Pd in 3/4 is nearly square planar. The bond distances (Å) in 3/4 are: Pd−S/Se, 2.3040(7)/2.402(2) and Pd−C, 1.961(3)/1.938(11).
Effect of Flower‐Like and Spherical Nanostructured MoS2 on the Adsorption Properties of Cr(VI) Ions
Authors: Fan Honglei , Wang Shuzhan , Qin Zeyun , Wang Haidong , Zhou Shaofeng , Liu Yaqing 
Published: March 2020

AbstractMoS2 nanostructures with different morphologies were synthesized using a simple in‐situ hydrothermal process by different surfactants like hexadecyl trimethyl ammonium bromide (CTAB) and polyvinyl pyrrolidone (PVP), and the effect of morphologies on the adsorption property for Cr(VI) were investigated. It can be found that flower‐like and spherical MoS2 nanostructures were synthesized and their morphologies largely effected the adsorption performance toward Cr(VI) ions. Flower‐like MoS2 exhibited the surface area of 41.9 m2 g−1 with fairly high adsorption capacity of 66.1 mg g−1 toward Cr(VI), fitting well to pseudo‐second order kinetic model and Langmuir isotherm model. Moreover, this as‐prepared nanostructured MoS2 also presented satisfying reusability for removal of Cr(VI) and were even suitable for the selective removal of Cr(VI) in the presence of NO3−. It may provide a potential route to enhance the adsorption property of MoS2 toward heavy metal ions through adjusting the morphology of the MoS2 sample, which would expand the applications of MoS2 in the field of treatment of the heavy metal wastewater.
Aerobic α‐Sulfonylation of Ketones with Zinc Sulfinates in Aqueous Micellar Media: Highly Selective Access to β‐Keto Sulfones
Authors: Fu Ying , Li Quan‐Zhou , Li Ming‐Peng , Du Zhengyin 
Published: March 2020

AbstractAn efficient, inexpensive and environmentally friendly synthesis of β‐ketosulfones, via NaI‐catalyzed oxidative sulfonylation of ketones with zinc sulfinates, employing ethylene dibromide (EDB) and air as the oxidants, is described. EDB was shown to be a mild organic oxidant to convert NaI into molecular iodine that promote the cross‐coupling reactions of zinc sulfinates with ketones, producing β‐ketosulfones. Mechanistic studies indicated that a radical pathway might be involved in the reaction process. The key feature of the present protocol is the far greater solubility of NaI and sulfinates in micellar arrays present in aqueous solution where the oxidative coupling reactions are taking place.
Recent Advances in Improving Phase Stability of Perovskite Solar Cells
Authors: Qiu Zhiwen , Li Nengxu , Huang Zijian , Chen Qi , Zhou Huanping 
Published: March 2020

AbstractOrganic–inorganic hybrid perovskite solar cells (PSCs) have demonstrated high efficiency and improved stability, which shows promising potential for commercialization. However, among all challenges, the material and device instability of the methylammonium lead iodide (MAPbI3) absorber are regarded as serious obstacles to the future development of devices for long‐term operation. Compared with conventional MAPbI3, formamidinium lead iodide (FAPbI3) and cesium lead iodide (CsPbI3) have attracted more attention due to their superior thermal stability. Due to their undesirable tolerant factor, however, these materials suffer from poor phase stability, which is worthy of careful investigation. This perspective highlights the recent progress on the phase stabilization of FAPbI3 and inorganic CsPbI3 materials with emphasis on the fundamental understanding of the origin of phase instability. In addition, strategies to fabricate corresponding devices toward high‐efficiency and long‐lifetime are discussed. This review sheds light onto the design and synthesis of FAPbI3 and inorganic CsPbI3 perovskite materials. In the end, the potential of FAPbI3 and inorganic CsPbI3 perovskite materials as stable absorbers is discussed, which promotes the development of corresponding solar cells and other optoelectronic devices for practical applications.
Computational DFT study of magnetite/graphene oxide nanoadsorbent: Interfacial chemical behavior and remediation performance of heavy metal hydrates from aqueous system
Authors: El‐Fawal Esraa M. , Saad Lamia , Moustafa Yasser M. 
Published: March 2020

AbstractHerein, magnetite/graphene oxide hybrid (MGO) was facilely synthesized and analyzed by various techniques such as X‐ray diffraction spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, Brunauer, Emmett, and Teller surface area analyzer, and Raman spectroscopy. A computational density functional theory (DFT) has been applied for the first time to determine the removal mechanism of zinc (Zn2+), nickel (Ni2+), and chromium (Cr6+) hydrates onto the prepared MGO. The adsorption binding energy and geometries of the metal hydrates with oxygen functional group (i.e., hydroxyl, epoxide, carboxylic, carbonyl groups, and magnetite on the MGO surface) were estimated. The complexes configurations comprised via sitting the metal ion perpendicular and above the MGO surface. The zinc hydrate portended to bind more strongly than Ni2+ and Cr6+. Zinc hydrate is favorable to coordinate with hydroxyl and carboxylic group than the other functional groups. The pseudo‐second‐order kinetic and Langmuir isotherm models are well convenient for kinetics and isotherm sorption process, respectively. The results determined that the sorption of heavy metals by nanostructure MGO was observed in the following order: zinc > nickel > chromium as revealed by the DFT computations. The maximum adsorption capacity of Zn2+, Ni2+, and Cr6+ was 333, 250, and 200 mg/g, respectively. Thermodynamic constants depicted that the sorption process is naturally instantaneous and exothermic. The calculated predicted results are fitted with the experimental results.Practitioner points

Combination of MGO with DFT calculations in the sorption of Zn, Ni, and Cr hydrates.

MGO applied on the removal of Zn+2, Ni+2, and Cr+6 with high sorption capacity.

DFT calculations revealed that Zn hydrate is more favorably adsorbed than others.

DFT calculations proved that ZnOH is favorable to coordinate with OH and COOH groups.

DFT calculation offers guidance on the mechanism of coordination of heavy metals.
T, Q and periods in SU(3) $$ \mathcal{N} $$ = 2 SYM
Authors: Fioravanti Davide , Poghosyan Hasmik , Poghossian Rubik 
Published: March 2020

Abstract
We consider the third order differential equation derived from the deformed Seiberg-Witten differential for pure $$ \mathcal{N} $$
N
= 2 SYM with gauge group SU(3) in Nekrasov- Shatashvili limit of Ω-background. We show that this is the same differential equation that emerges in the context of Ordinary Differential Equation/Integrable Models (ODE/IM) correspondence for 2d A2 Toda CFT with central charge c = 98. We derive the corresponding QQ and related T Q functional relations and establish the asymptotic behaviour of Q and T functions at small instanton parameter q → 0. Moreover, numerical integration of the Floquet monodromy matrix of the differential equation leads to evaluation of the A-cycles a1,2,3 at any point of the moduli space of vacua parametrized by the vector multiplet scalar VEVs (tr 𝜙2) and (tr 𝜙3) even for large values of q which are well beyond the reach of instanton calculus. The numerical results at small q are in excellent agreement with instanton calculation. We conjecture a very simple relation between Baxter’s T -function and A-cycle periods a1,2,3, which is an extension of Alexei Zamolodchikov’s conjecture about Mathieu equation.
Investigation of nutritional characteristics and free radical scavenging activity of wild apple, pear, rosehip, and barberry from the walnut-fruit forests of Kyrgyzstan
Authors: Smanalieva Jamila , Iskakova Janyl , Oskonbaeva Zhyldyz , Wichern Florian , Darr Dietrich 
Published: March 2020

AbstractThis study is based on 2-year experimental results aimed at evaluating the nutritional value and pomological characteristics of wild fruits and berries from the walnut-fruit forests of southern Kyrgyzstan including apple (Malus sieversii var. kirgizorum), pear (Pyrus korshinskyi Litv.), rosehip (Rosa canina), or barberry (Berberis oblonga). Wild pear, characterised by its high level of alimentary fibres (8.76 g/100 g), offers a promising potential for industrial pectin production. Barberry features higher radical scavenging activity (antioxidant activity) as compared to Iranian and Turkish ecotypes. Among the investigated fruits and berries, barberry and rosehip represent a good source of bioactive phytochemicals due to their high phenolic, anthocyanin, vitamin C and mineral contents. Regular consumption of such wild fruits can contribute between 26 and 100% to the recommended dietary allowance of selected mineral elements (Ca, Zn, Fe, Mn) helping to combat micro-nutrient deficiency in humans.