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Gamma-ray bursts (GRBs) are the most intense explosions in the Universe. GRBs with extended emission (GRBs EE) constitute a small subclass of GRBs. GRBs EE are divided into EE-I GRBs and EE-II GRBs, according to the Amati empirical relationship rather than duration. We test here if these two types of GRB have different origins based on their luminosity function (and formation rate). Therefore, we use Lynden-Bell's c − method to investigate the luminosity function and formation rate of GRBs with EE without any assumption. We calculate the formation rate of two types of GRBs. For EE-I GRBs, the fitting function can be written as ρ(z) ∝ (1 + z)−0.34 ± 0.04 for z < 2.39 and ρ(z) ∝ (1 + z)−2.34 ± 0.24 for z > 2.39. The formation rate of EE-II can describe as ρ(z) ∝ (1 + z)−1.05 ± 1.10 for z < 0.43 and ρ(z) ∝ (1 + z)−8.44 ± 1.10 for z > 0.43. The local formation rate is |$\rho (0) = 0.03\, {\rm Gpc}^{-3} \, {\rm yr}^{-1}$| for some EE-I GRBs and |$\rho (0) = 0.32 \, {\rm Gpc}^{-3} \, {\rm yr}^{-1}$| for EE-II GRBs. Based on these results, we provide new evidence that the origins of EE-I GRBs are different from EE-II GRBs from the perspective of event rate. The EE-I GRB could be produced from the death of the massive star, but EE-II GRB may come from other processes that are unrelated to the star formation rate. Our findings indicate that the GRBs with EE could have multiple production channels. [ABSTRACT FROM AUTHOR]

This article discusses a case of 5,10-Methylenetetrahydrofolate reductase (MTHFR) deficiency, a rare autosomal recessive disorder, presenting as adult-onset spastic paraplegia. MTHFR deficiency is characterized by low plasma methionine levels, hyperhomocysteinemia, and homocysteinuria. The clinical symptoms of MTHFR deficiency can vary widely, from severe neurodevelopmental delays to gait disorders. The case study highlights the clinical heterogeneity of MTHFR deficiency and emphasizes the need for clinicians to be aware of this rare disease. The patient in the case study was treated with multivitamins, folate, and methylcobalamin, resulting in significant improvement in symptoms and biochemical abnormalities. The article concludes by stating that this case expands the understanding of MTHFR mutations and provides a basis for genetic diagnosis and counseling. [Extracted from the article]

To develop a nomogram to predict lymphovascular invasion (LVI) in gastric cancer by integrating multiphase computed tomography (CT) radiomics and clinical risk factors. One hundred and seventy-two gastric cancer patients (121 training and 51 validation) with preoperative contrast-enhanced CT images and clinicopathological data were collected retrospectively. The clinical risk factors were selected by univariate and multivariate regression analysis. Radiomic features were extracted and selected from the arterial phase (AP), venous phase (VP), and delayed phase (DP) CT images of each patient. Clinical risk factors, radiomic features, and integration of both were used to develop the clinical model, radiomic models, and nomogram, respectively. Radiomic features from AP (n= 6), VP (n= 6), DP (n= 7) CT images and three selected clinical risk factors were used for model development. The nomogram showed better performance than the AP, VP, DP, and clinical models in the training and validation datasets, providing areas under the curves (AUCs) of 0.890 (95% CI: 0.820–0.940) and 0.885 (95% CI:0.765–0.957), respectively. All models indicated good calibration, and decision curve analysis proved that the net benefit of the nomogram was superior to that of the clinical and radiomic models throughout the vast majority of the threshold probabilities. The nomogram integrating multiphase CT radiomics and clinical risk factors showed favourable performance in predicting LVI of gastric cancer, which may benefit clinical practice. • Tumor location, cT category and cN category were independent risk factors of LVI. • Five models: clinical model, AP model, VP model, DP model and nomogram. • The nomogram based on clinical risk factors and radiomics features performed well. [ABSTRACT FROM AUTHOR]

In this paper, we first propose online and offline channel incentive models (CIM) with consideration of the consumers’ rational choices to solve and simulate the channel incentive problem (CIP) for supplier. We investigate whether the increase in demand along with channel incentive activities is enough to compensate for the decrease in the supplier's marginal revenue and retailers could benefit from the increase in market demand when retail channel information reference factor satisfies a certain threshold value. Our results show that decision preference of channel members is influenced by the reference factor and marginal revenue. Furthermore, the numerical achievements indicate that there is a unique optimal channel incentive coefficient related to the rational choices in benchmark channel incentive model (BCIM) for omnichannel. Both suppliers and retailers would benefit from the increased orders. Channel efficiency is improved from 72 % to 79 %. And the supplier profit function is a concave function of supplier's input in the offline channel incentive in the offline CIM. [ABSTRACT FROM AUTHOR]

In this paper, a theoretical analysis reveals that system radiation transmission nonuniformity and system radiation conversion nonuniformity have different forms. A colour imaging system response nonuniformity model is then proposed according to the two kind of nonuniformity of three channels. The model includes two models, one for brightness and one for chromaticity. The brightness model is built according to the nonuniformity of single channel. The chromaticity model is built as an error ellipse in the chromaticity diagram. The error ellipse can be also used as a representation parameter of the radiation conversion nonuniformity. The proposed models were verified using three commercial digital cameras. The experimental results show that the proposed nonuniformity model is correct. Moreover, the proposed representation parameter is an effective way to evaluate and characterize the nonuniformity of a colour imaging system. This research has value as a reference for the correction and evaluation of response nonuniformity in colour imaging systems. [ABSTRACT FROM AUTHOR]

The nonlinear response affects the effect of imaging system response non-uniformity correction (NUC) methods. Most of the methods are effective in a certain range of responses. In this paper, a new NUC method is proposed based on the mechanism of imaging system response non-uniformities production. Optical system-related non-uniformity is described as radiation transmission non-uniformity (RTNU) and detector-related non-uniformity is described as radiation conversion non-uniformity (RCNU). The RTNU is removed by inverse operation and RCNU is removed by regularization optimization. We verify the proposed method with respect to visual effect evaluation of actual scene images and three performance metrics evaluation of statistical F ratio, F-norm roughness and chromatic aberration ellipse. The experimental results verify the effect of our method. The proposed method is effective for NUC in a larger range of responses. [ABSTRACT FROM AUTHOR]

We demonstrate optical cycling and laser cooling of a cryogenic buffer-gas beam of calcium monohydride (CaH) molecules. We measure vibrational branching ratios for laser cooling transitions for both excited electronic states A and B. Furthermore, we measure that repeated photon scattering via the A ← X transition is achievable at a rate of ∼ 1.6 Ă— 1 0 6 photons sâˆ'1 and demonstrate interaction-time limited scattering of ∼ 200 photons by repumping the largest vibrational decay channel. We also demonstrate a sub-Doppler cooling technique, namely the magnetically assisted Sisyphus effect, and use it to cool the transverse temperature of a molecular beam of CaH. Using a standing wave of light, we lower the transverse temperature from 12.2(1.2) mK to 5.7(1.1) mK. We compare these results to a model that uses optical Bloch equations and Monte Carlo simulations of the molecular beam trajectories. This work establishes a clear pathway for creating a magneto-optical trap (MOT) of CaH molecules. Such a MOT could serve as a starting point for production of ultracold hydrogen gas via dissociation of a trapped CaH cloud. [ABSTRACT FROM AUTHOR]

In this paper, a progressive damage analysis of two-dimensional C/SiC composites and superalloy mechanically fastened joint with countersunk bolt is implemented to simulate the uniaxial tensile loading process by using a user-defined subroutine UMAT embedded into the general package Abaqus. On basis of the developed damage model, a parametric study is carried out to illustrate the effects of countersunk parameters on tensile performance for the hybrid bolted joint. It is found that there are negligible changes in the stiffness of the bolted joint, as the countersunk height varies from 1.5 to 2.5 mm for the considered bolt-head diameter cases. However, the failure load of the ceramic matrix composite and superalloy hybrid joint exhibits significant changes under different combinations of countersunk parameters. Increasing the countersunk height of the bolt intensifies the initial stress concentration and results in the redistribution of stress around the hole-edge area of the composite material plate. For the bolt-head diameter and countersunk height equal to 9.4 and 1.5 mm, respectively, the joint structure ensures the maximum load-bearing capacity for the studied joint with a countersunk bolt. [ABSTRACT FROM AUTHOR]

A novel calibration method for a multi-line structured laser light vision sensor using a planar target is presented. The method can be summarized as first, the camera model is changed by projecting the point from the two-dimensional (2-D) image plane to the world coordinate system, wherein the intrinsic parameters of the camera are calibrated accurately in advance. Next, by means of a planar target with a cruciform pattern, multiple sets of three-dimensional (3-D) feature points are solved in the camera coordinate system. Last, a new method is proposed for solving the structured light planes in which a uniform objective function is determined and the priori position relation of the structured light planes is considered as a constraint. In this way the prior geometric relation of the planes can be accurately transplanted into the camera coordinate system. Experimental data demonstrate that the proposed method exhibits better accuracy and repeatability. [ABSTRACT FROM AUTHOR]

Global ocean mean salinity S is a key indicator of the Earth's hydrological cycle and the exchanges of freshwater between land and ocean, but its determination remains a challenge. Aside from traditional methods based on gridded salinity fields derived from in situ measurements, we explore estimates of S based on liquid freshwater changes derived from space gravimetry data corrected for sea ice effects. For the 2005-2019 period analyzed, the different S series show little consistency in seasonal, interannual, and long-term variability. In situ estimates show sensitivity to choice of product and unrealistic variations. A suspiciously large rise in S since ~2015 is enough to measurably affect halosteric sea level estimates and can explain recent discrepancies in the global mean sea level budget. Gravimetrybased S estimates are more realistic, inherently consistent with estimated freshwater contributions to global mean sea level, and provide a way to calibrate the in situ estimates. [ABSTRACT FROM AUTHOR]

This study is based on continuum damage mechanics and constructs an improved macro–micro-two-scale model to predict the fatigue life of engineering metallic materials subjected to variable amplitude loading. To account quantitatively for the fatigue damage retarding effect of higher load on lower ones in a loading sequence, the cyclic plastic response curve of microscopic weak inclusion is independently designed. Meanwhile, an improved two-scale fatigue damage model in rate form is proposed by introducing a new exponent function acted on the equivalent plastic strain term in the model for taking account of fatigue mean stress effect under variable amplitude loading. The parameters of the two-scale fatigue damage model are identified through an inverse approach based on fatigue test results under constant amplitude loading. The predictive accuracy of the proposed model is validated by fatigue test data of Al 2024-T3 standard coupon and plate with a hole under different variable amplitude loading. [ABSTRACT FROM AUTHOR]

Microalgae such as dinoflagellate and diatom are the major food source of bivalve species, and sufficient food intake contributes to the immunity and the growth of bivalves. In the present study, a monoamine oxidase gene (named as CgMAO), which is the rate-limiting enzyme of norepinephrine (NE) biosynthesis, was cloned from C. gigas. After the oysters were fed with a diet rich in diatom for 21 and 40 d, the NE contents in oyster serum, as well as the mRNA expression of CgMAO in oyster haemocytes, increased significantly compared with control group. Besides, the mRNA expression of cytokines CgTNF-1 and CgIL17-5 in haemocytes and the activities of immune-related enzymes (SOD and LYZ) in oyster serum also increased significantly after diatom feeding. These results collectively suggested that sufficient microalgae intake might significantly enhance the antibacterial capacity in oyster by prompting the biosynthesis of NE and triggering the subsequent antibacterial processes modulated by NE. [ABSTRACT FROM AUTHOR]

Miscanthus sinensis Anderss. is a good candidate for C4 bioenergy crop development for marginal lands. As one of the characteristics of marginal lands, salinization is a major limitation to agricultural production. The present work aimed to investigate the possible factors involved in the tolerance of M. sinensis C4 photosynthesis to salinity stress.Seedlings of two accessions (salt‐tolerant 'JM0119' and salt‐sensitive 'JM0099') were subjected to 0 mm NaCl (control) or 250 mm NaCl (salt stress treatment) for 2 weeks. The chlorophyll content, parameters of photosynthesis and chlorophyll a fluorescence, activity of C4 enzymes and expression of C4 genes were measured.The results showed that photosynthesis rate, transpiration rate, chlorophyll content, PSII operating efficiency, coefficient of photochemical quenching, activity of phosphoenolpyruvate carboxylase (PEPC) and pyruvate, orthophosphate dikinase (PPDK) and gene expression of PEPC and PPDK under salinity were higher after long‐term salinity exposure in 'JM0119' than in 'JM0099', while activity of NADP‐malate dehydrogenase (NADP‐MDH) and NADP‐malic enzyme (NADP‐ME), together with expression of NADP‐MDH and NADP‐ME, were much higher in 'JM0099' than in 'JM0119'.In conclusion, the increased photosynthetic capacity under long‐term salt stress in the salt‐tolerant relative to the salt‐sensitive M. sinensis accession was mainly associated with non‐stomatal factors, such as reduced chlorophyll loss, higher PSII operating efficiency, enhanced activity of PEPC and PPDK and relatively lower activity of NADP‐ME. [ABSTRACT FROM AUTHOR]

Characteristics of facial skin problems and microbiome variation during wearing masks for fighting against COVID-19 Facial skin problems were defined as suffering from itching, stress injury, allergic dermatitis, fungal skin disease and skin maceration while wearing masks against COVID-19. Those with sensitive skin had the highest incidence due to the extreme sensitivity to external stimuli.5 Those with dry skin had a slightly higher incidence of facial skin problems than those with oily skin. [Extracted from the article]

The degree of steam overlay and descriptions of the migration rules for vapor front are considered one of the greatest challenges to research the seepage laws of steam assisted gravity drainage. In order to surmount these challenges, the theory of percolation mechanics are introduced, combined with the well group structure of steam assisted gravity drainage, we do workings such as establishing the mathematical model of pressure field, applying the steam overlap theory and simplifying the steam overlap coefficient, adopting the technology of database and mapping to display the trends of vapor front intuitively. At last, combined with production factor and reservoir thickness, we analyze the sweep volume of steam and the influence rules of the vapor front migration. Understanding the achievements will provide scientific basis to the improvement of steam's sweep volume in symmetry elements, displaying the working degree of reservoirs intuitively as well as the efficient development of steam assisted gravity drainage. [ABSTRACT FROM AUTHOR]

Haematoxylin and eosin, original magnification (c) × 15, (inset) × 2.5. gl To our knowledge, this is the first case of KD concomitant with AD successfully treated with JAK inhibitors. (c) The histological features of KD were a nodular lymphocytic infiltrate with germinal centres involving the dermis, and reactive germinal centres surrounded by lymphocytes and eosinophils. GLO:DF2/01oct21:ced14671-fig-0001.jpg PHOTO (COLOR): 1 (a,b) Representative photographs of the patient with concomitant atopic dermatitis (AD) and Kimura disease (KD), showing improvement of (a) AD and (b) KD from Month 0 to 3. [Extracted from the article]

To better understand the arc plasma axial motion under an axial magnetic field, a high-speed charge-coupled device camera was used to observe the arc plasma images in a magnetically rotating arc plasma generator. Experimental results indicate that the arc plasma moves towards the cathode bottom as the magnetic field strength increases, while a higher arc current facilitates the cathode arc root to move to the cathode terminus. A two-dimensional coupled model was used to analyze the arc plasma axial motion under different magnetic field strengths. The numerical simulation shows that the arc plasma is axially compressed and curves towards the cathode bottom. It is proposed that the arc plasma structure is derived from the strong backflow from the anode outlet, which is induced by the low-pressure region near the cathode. Moreover, the coupled model predicts the movement of the cathode arc root in agreement with the experimental results. It is inferred that the movement of the cathode arc root is relevant to the energy flux, which is transported from the arc column plasma to the cathode surface. [ABSTRACT FROM AUTHOR]

Background and purpose: This study was to investigate the prevalence and cardiovascular risk factors (CRFs) of asymptomatic intracranial atherosclerotic stenosis (aICAS) amongst middle‐aged and older adults living in rural communities in China. Methods: This population‐based study included 2019 subjects (aged ≥40 years, 52.3% women) who were free of stroke and living in rural communities in China. From October 2017 to May 2018, data on demographics, CRFs and health conditions were collected through face‐to‐face interviews, physical examination and laboratory tests. Asymptomatic ICAS was detected through a two‐phase procedure: a screening phase with transcranial Doppler ultrasound, followed by a diagnostic phase with magnetic resonance angiography examination. Multivariable logistic regression models were used to analyse CRFs associated with aICAS. Results: Of the 2019 participants, aICAS was detected in 153 persons. The overall prevalence of aICAS was 7.6%, and the prevalence of moderate‐to‐severe aICAS was 5.0%. The multi‐adjusted odds ratio (95% confidence interval) of aICAS associated with CRFs was 2.40 (1.56–3.69) for hypertension, 1.91 (1.32–2.76) for high hypersensitive C‐reactive protein, 1.68 (1.14–2.49) for diabetes and 1.61 (1.08–2.41) for overweight or obesity. When these four CRFs were aggregated, compared with participants without any of these factors, the multi‐adjusted odds ratios (95% confidence interval) of aICAS for persons concurrently having one, two and three or more of these factors were 1.14 (0.52–2.48), 2.91 (1.42–5.99) and 5.51 (2.64–11.50), respectively (P for linear trend <0.001). Conclusions: Asymptomatic ICAS is common amongst rural‐dwelling middle‐aged and older Chinese people. Hypertension, diabetes, overweight or obesity and high hypersensitive C‐reactive protein, especially when coexisting, are strongly associated with aICAS. [ABSTRACT FROM AUTHOR]

Since the discovery of C60 fullerene, considerable efforts have been devoted to find other elements with similar hollow cage structures. However, search for hollow metallic cages with a diameter similar to that of C60 fullerene has been elusive. We describe a procedure for the rational design of metallic cages by suitably choosing their size, composition, and charge state. A 22 karat nanogolden cage with a diameter of about 8.5 Å and consisting of 12 Al and 20 Au atoms is found to be metastable, which can be stabilized by embedding a Mn4 cluster. In contrast to bulk Mn, which is antiferromagnetic, and isolated Mn4 cluster, which is ferromagnetic with a giant magnetic moment of 20μB, the Mn4@Al12Au20 endohedral complex exhibits magnetic bistability with 0μB and 14μB configurations being energetically nearly degenerate. These results, based on density functional theory, open the door to design a novel class of endohedral complexes with possible applications. [ABSTRACT FROM AUTHOR]

A first-principles calculation based on gradient corrected density functional theory reveals unusual properties of a Cu atom interacting with F. Up to six F atoms are bound to a single Cu atom with electron affinities steadily rising as successive F atoms are attached, reaching a peak value of 7.2 eV in CuF5. The large energy gaps between the highest occupied and lowest unoccupied molecular orbitals, both in neutral and anionic form, provide further evidence of their stability. These unusual properties brought about by involvement of inner shell 3d-electrons not only allow CuFn to belong to the class of superhalogens but also show that its valence can exceed the nominal value of 1 and 2. [ABSTRACT FROM AUTHOR]

The deep level luminescence of crack-free Al0.25Ga0.75N layers grown on a GaN template with a high-temperature grown AlN interlayer has been studied using spatially resolved cathodoluminescence (CL) spectroscopy. The CL spectra of Al0.25Ga0.75N grown on a thin AlN interlayer present a deep level aquamarine luminescence (DLAL) band at about 2.6 eV and a deep level violet luminescence (DLVL) band at about 3.17 eV. Cross-section line scan CL measurements on a cleaved sample edge clearly reveal different distributions of DLAL-related and DLVL-related defects in AlGaN along the growth direction. The DLAL band of AlGaN is attributed to evolve from the yellow luminescence band of GaN, and therefore has an analogous origin of a radiative transition between a shallow donor and a deep acceptor. The DLVL band is correlated with defects distributed near the GaN/AlN/AlGaN interfaces. Additionally, the lateral distribution of the intensity of the DLAL band shows a domainlike feature which is accompanied by a lateral phase separation of Al composition. Such a distribution of deep level defects is probably caused by the strain field within the domains. [ABSTRACT FROM AUTHOR]

Using gradient-corrected density functional theory and supercell technique, we have calculated total energies, electronic structure, and magnetic properties of Cr-doped ZnTe in both bulk and thin-film configurations. Calculations with full geometry optimization for a Zn1-xCrxTe supercell were carried out for different Cr concentrations (x=0.095, 0.143, and 0.19) and by varying the sites Cr atoms occupy. We show that the ferromagnetic phase of Zn1-xCrxTe in both bulk and thin film is energetically the most preferable state irrespective of the concentration and/or site occupation of the Cr atom. The strong hybridization between Cr 3d and Te 5p states is found to be responsible for the ferromagnetic coupling, in agreement with recent experiments. [ABSTRACT FROM AUTHOR]

Contrary to the conventional understanding that atomic clusters usually differ in properties and structure from the bulk constituents of which they are comprised, we show that even a dimer of tungsten oxide (WO3)2 possesses bulklike features and the geometry of a small cluster containing only 4 tungsten and 12 oxygen atoms bears the hallmarks of crystalline tungsten oxide, WO3. This observation, based on a synergistic approach involving mass distributions under quasisteady state conditions, photoelectron spectroscopy, and first principles molecular orbital theory, not only illustrates the existence of a class of strongly covalent or ionic materials whose embryonic forms are tiny clusters but also lends the possibility that a fundamental understanding of complex processes such as catalytic reactions on surfaces may be achieved on an atomic scale with clusters as model systems. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Using density functional theory with generalized gradient approximation for exchange and correlation, we show that otherwise antiferromagnetically coupled chromium atoms in very small chromium clusters couple ferromagnetically when doped with a nitrogen atom, thus leading to giant magnetic moments. For example, the magnetic moment of Cr[sub 2]N is found to be 9μ[sub B] while that of Cr[sub 2] is 0μ[sub B]. Strong bonding between Cr and N atoms brings about this magnetic transition. The Cr atoms nearest neighbor to N couple ferromagnetically with each other and antiferromagnetically with nitrogen. The significance of these results in understanding the ferromagnetic order in Cr-doped GaN is discussed. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A 39-year-old woman presented with sudden onset bilateral ptosis and binocular diplopia for 3 days. To avoid diagnostic delay, clinicians should include midbrain infarction into differential diagnosis when facing patients with sudden onset bilateral ptosis or impaired adduction. [Extracted from the article]

In this paper, a new finite element method, termed the generalized modal element method (GMEM), is proposed. In GMEM, the element stiffness is derived by decomposing element deformation patterns into individual element generalized modes, where different methods are used to construct the generalized modes. Specifically, three different modal construction methods, including analytical method, assumed displacement method and traditional finite element technique, are proposed for developing the element generalized modes. The concept of modal local coordinate systems is also proposed to ensure the element frame invariance when using polynomial displacement functions, which successfully enables one to use the analytical solutions derived from governing differential equations to develop high accuracy element formulations. An asymmetric hexahedral solid element and a symmetric hexahedral solid element are subsequently derived by using GMEM. The displacement functions of the elemental 24 generalized modes are expressed in terms of Cartesian coordinates so that the element behavior is independent of mesh distortions. Furthermore, the first 21 generalized modes are derived from analytical method making the element capable of avoiding common locking phenomena. Several benchmark problems are performed to demonstrate the accuracy and performance of the new element formulations in linear static and frequency analysis. [ABSTRACT FROM AUTHOR]

In this paper, two eight-node asymmetric solid-shell elements are firstly presented to illustrate the use of traditional finite element technique in GMEM for constructing new finite element formulations. In these two elements, the analytical method is utilized to derive the displacement functions of the basic in-plane modes, which makes the resulted elements free of mesh distortions for these modes. For out-of-plane modes, the Mindlin plate elements CQUAD4 and QTS4 are integrated to calculate the corresponding modal displacement vectors and modal force vectors of solid-shell elements. As a result, the displacement functions of the plate-bending element range up to three orders of magnitude. On the other hand, since the asymmetric elements cannot be applied to frequency analysis, two symmetric solid-shell elements are proposed by using a modal transformation method, in which the in-plane modes are derived from the previous proposed symmetric solid element S-MEM8S and the out-of-plane modes are constructed by plate elements CQUAD4 and QTS4, respectively. Various benchmarks including linear static and frequency analysis are presented to demonstrate the accuracy and efficiency of the presented elements. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Hydrophobicity is due to maximize hydrogen bonding of water. • As two identical solutes are dissolved into ambient water, Rc is 3.25 Å. • In the association of solutes, it is divided into H1w and H2s processes. Abstract The dependence of hydrophobic interactions as a function of solute size has been investigated as an extension to our recent study detailing the physical origin of hydrophobic interactions. By determining the hydration free energy of two identical hydrophobic solutes dissolved in water, the critical radius (Rc) was calculated to be 3.25 Å, at ambient conditions. With reference to Rc, an initial process and a hydrophobic solvation process have been shown to govern the behavior of the dissolved solutes. These processes can be demonstrated by molecular dynamic simulations on C 60 -C 60 fullerenes in water, and CH 4 dimers in water. In the case of the former, by decreasing the distance between the C 60 fullerene molecules, the hydrophobic interactions switch between H1w- and H2s-type hydrophobic processes. Additionally, maximizing hydrogen bonding was found to be the driving force that influenced the behavior of the hydrophobic solutes. [ABSTRACT FROM AUTHOR]

Aim: To analyse subsolid nodules (SSNs) detected during low-dose (LD) computed tomography (CT) screening and investigated whether CT texture analysis parameters can predict the malignancy and growth trends of GGNs.Materials and Methods: In this retrospective study, 89 SSNs were detected in 86 LDCT screening participants, including 42 pure ground-glass nodules (GGNs) and 47 part-solid GGNs. In these participants, 28 SSNs were diagnosed as lung cancer at histopathology, and 61 SSNs from participants who underwent at least two LDCT imaging studies. All nodules were divided into three groups: cancer group, growth group, and non-growth group. The nodule size, volume, attenuation, volume doubling time (VDT), and texture parameters (mean value, uniformity, entropy and energy) were assessed, respectively.Results: The entropy of the cancer group was significantly higher than that of the growth and non-growth groups (pure GGNs: p=0.009, 0.001; part-solid GGNs: p=0.012, 0.004). The energy of the cancer group was significantly lower than that of the other groups (pure GGNs: p=0.043, 0.021; part-solid GGNs: p=0.001, 0.002). A good positive correlation was found between uniformity and VDT (p=0.022).Conclusion: Different CT texture parameters show good predictive value for SSNs detected at LDCT screening: the entropy and energy differences between malignant pulmonary nodules and others could be a helpful quantitative index to predict the malignancy of SSNs. Uniformity could be used to predict the growth probability of pure GGNs at baseline to pay more attention to these nodules. Moreover, the follow-up and treatment plan could be more targeted. [ABSTRACT FROM AUTHOR]

A fiber-reaction zone-matrix three-phase model is developed to evaluate the interfacial fracture toughness of titanium alloys reinforced by SiC monofilaments. Based on fracture mechanics, theoretical equations of GIIc are presented, and the effects of several key factors such as crack length and the interface reaction zone thickness on the critical applied stress necessary for crack growth and interfacial fracture toughness are discussed. Finally, the interfacial fracture toughness of typical composites including Sigma1240/Ti-6Al-4V, SCS-6/Ti-6Al-4V, SCS-6/Timetal 834, SCS-6/Timetal 21s, SCS-6/Ti-24Al-11Nb and SCS-6/Ti-15V-3Cr are predicted by the model. The results show that the model can reliably predict the interfacial fracture toughness of the titanium matrix composites. [ABSTRACT FROM AUTHOR]

The vibrational and electronic structures of p-phenylenediamine radical cation have been studied using time-resolved resonance Raman spectroscopy and molecular orbital calculations. The Raman spectra in aqueous solution show striking variations in intensity profile when excitation is varied from 340 to 480 nm. Excitation in resonance with the 460–480 nm absorption shows enhancement of only totally symmetric vibrations. Most prominent are the δNH2 scissor mode at 1658 cm-1 and the Wilson modes ν8a (CC stretch) at 1644 cm-1, ν7a (CN stretch) at 1423 cm-1, and ν9a (CH bend) at 1184 cm-1. Also observed are ν1 (ring breathe) at 840 cm-1 and ν6a (CCC bend) at 467 cm-1. With excitation in the 340–410 nm region the ν1 band becomes relatively stronger and an additional band at 1524 cm-1 appears. This latter band, which dominates the spectrum at 360 nm, is assigned to the nontotally symmetric vibration ν8b (CC stretch) having b3g symmetry that gains intensity through vibronic coupling. Raman spectra of ring- and amine-deuterated radicals allow distinction of overtone and combination bands enhanced by Fermi resonance from fundamentals due to δNH2 and ν8a (CC stretch) modes in the 1600–1700 cm-1 region. The theoretical calculations show reasonable agreement with the observed vibrational frequencies and lead to detailed information on the bond structure and normal modes of the radical. The calculated CN bond lengths of 1.33 Å are intermediate between lengths typical of single and double bonds in aromatic amines. The calculations also allow interpretation of the experimental absorption spectrum. The broad medium intensity absorption peaked at 460 nm with a shoulder at 480 nm is assigned to a 2B3u ←2B2g transition, the very weak 360 nm absorption to 2Au ← 2B2g and the very strong ∼325 nm absorption to a higher 2B3u ← 2B2g.Calculations with the simple relation Ik∝... [ABSTRACT FROM AUTHOR]

Studies the effects of nitrogen on oxygen precipitation in silicon. Background to the study; Experimental procedure; Results and discussion.

Presents the results of photoluminescence, ellipsometric, micro-Raman, and Hall measurements of thick In[subx]Ga[sub1-x]As epilayers grown by metal organic vapor phase epitaxy on slightly misoriented GaAs substrates. Background to the study; Experimental procedures; Results and discussions.

Discusses a study on the correlation between substitutional carbon concentration and interstitial oxygen concentration in silicon. Experimental procedures; Oxygen precipitation in the presence of carbon; Interaction of carbon and oxygen.

New experimental rate coefficients are reported for the H2(D2)+CN→H(D)CN+H(D) reactions over the temperature range 209 to 740 K for H2 and 250 to 740 K for D2. Previous reduced dimensionality reaction probabilities for the reaction with H2, and new ones for the reaction with D2 are used to obtain analogous rate coefficients. In addition, reaction probabilities and rate coefficients for vibrationally excited reactants H2(v=1), D2(v=1), or CN(v=1) are presented. Comparisons of the calculated rate coefficients are made with the new and previous experiments, especially those of Sims and Smith [Chem. Phys. Lett. 149, 565 (1988)]. [ABSTRACT FROM AUTHOR]

Background: Although numerous multicentre studies have estimated the association between ozone exposure and mortality, there are currently no nationally representative multicentre studies of the ozone-mortality relationship in China.Objective: To investigate the effect on total (nonaccidental) and cause-specific mortality of short-term exposure to ambient ozone, and examine different exposure metrics.Methods: The effects of short-term exposure to ozone were analysed using various metrics (daily 1-h maximum, daily 8-h maximum and daily average) on total (nonaccidental) and cause-specific (circulatory and respiratory) mortality from 2013 to 2015 in 34 counties in 10 cities across China. We used distributed lag nonlinear models for estimating county-specific relative risk of mortality and combined the county-specific relative rates by conducting a random-effects meta-analysis.Results: In all-year analyses, a 10 μg m-3 increase in daily average, daily 1-h maximum and daily 8-h maximum ozone at lag02 corresponded to an increase of 0.6% (95% CI: 0.33, 0.88), 0.26% (95% CI: 0.12, 0.39) and 0.37% (95% CI: 0.2, 0.55) in total (nonaccidental) mortality, 0.66% (95% CI: 0.28, 1.04), 0.31% (95% CI: 0.11, 0.51) and 0.39% (95% CI: 0.16, 0.62) in circulatory mortality, and 0.57% (95% CI: -0.09, 1.23), 0.11% (95% CI: -0.22, 0.44) and 0.22% (95% CI: -0.28, 0.72) in respiratory mortality, respectively. These estimates had a different seasonal pattern by cause of death. In general, the seasonal patterns were consistent with the times of year when ozone concentrations are highest.Conclusions: Our findings suggest that in China, the acute effects of ozone are more closely related to daily average exposure than any other metric. [ABSTRACT FROM AUTHOR]

Reed contains a naturally-occurring gene resource base to resist cadmium stress. Transcriptome profiling is conducive to cloning the cadmium-tolerance genes in reed. Reed roots under cadmium stress were sampled, and the Illumina HiSeq™ 2500 transcriptome sequencing was performed. A total of 286,439 unigenes were obtained after de novo assembly. There were 22,304 up-regulating differentially expressed unigenes and 15,711 down-regulation. Two-level clustering formed an accurate heatmap to compare between expression fold-change classes and between treatment classes. The gene ontology terms were mainly enriched into biological regulation, metabolic process, response to stimulus, cell component, catalytic activity, proton-transporting two-sector ATPase and binding. Noticeably, the catalytic activity was mainly forwarded to oxidoreductase activity and antioxidant activity. There were obviously-enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, phenylpropanoid biosynthesis, phenylalanine metabolism, ribosome and photosynthesis. Beta-glucosidase EC: 3.2.1.21 was up-regulation in the phenylpropanoid biosynthesis pathway. Up-regulation of phenylpyruvate tautomerase EC: 5.3.2.1 catalyzes the production of 2-hydroxy-3-phenylpropanoate in the phenylalanine metabolism pathway. In the photosynthesis pathway, there was up-regulation of petN, petH, photosystems I/II, LHCA4 and LHCB3. The protein-protein interaction network showed that beta-glucosidase EC: 3.2.1.21 interacted with c129889_g1 and c115092_g3; up-regulation of photosystems II c111052 interacted with c93463_g1 and c121697_g3. Two up-regulating enzymes EC: 3.2.1.21 and EC: 5.3.2.1 may be the candidates to improve cadmium tolerance in reed. The photosynthesis with light-harvesting and electron transport plays important roles in reed cadmium tolerance. The interacting proteins c129889_g1, c115092_g3, c93463_g1 and c121697_g3 are putative to involve in cadmium tolerance. The current study is promising to provide the profile data for cloning these reed genes. [ABSTRACT FROM AUTHOR]

We investigated enhancement of articular cartilage regeneration using a combination of human adipose derived stem cells (hADSCs) and TGF-β3 microspheres (MS) in vivo. Poly-lactic-co-glycolic acid (PLGA)MS were prepared using a solid/oil/water emulsion solvent evaporation-extraction method. The morphology of the MS was evaluated by scanning electron microscopy (SEM). The release characteristic of the TGF-β3 MS was evaluated. A New Zealand rabbit model for experimental osteoarthritis (OA) was established using the anterior medial meniscus excision method. Thirty OA rabbits were divided randomly into three groups according to different treatments of the right knee joints on day 7 after surgery: hADSCs/MS group received injection of both hADSCs and TGF-β3 MS; hADSCs group was injected with hADSCs; control group was injected with normal saline. Gross observation, histological staining and RT-PCR for collagen II and aggrecan) were used to assess the severity of OA and for evaluating the effect of combined use of hADSCs and TGF-β3 MS on articular cartilage regeneration in vivo. The MS were spherical with a smooth surface and the average diameter was 28 ± 2.3 µm. The encapsulation efficiency test showed that 73.8 ± 2.9% of TGF-β3 were encapsulated in the MS. The release of TGF- β3 lasted for at least 30 days. At both 6 and 12 weeks after injection, three groups exhibited different degrees of OA. Histological analysis showed that the hADSCs/MS group exhibited less OA than the hADSCs group, and the control group exhibited the most severe OA. Real-time RT-PCR showed that the gene expression of both collagen II and aggrecan were significantly up-regulated in the hADSCs/MS group. At 12 weeks after injection, the hADSCs/MS group also exhibited less OA than the other two groups. Combined use of hADSCs and TGF-β3 MS promoted articular cartilage regeneration in rabbit OA models. [ABSTRACT FROM AUTHOR]

An outbreak of hydropericardium syndrome has been ongoing in East China since 2015. To decipher the disease etiology, 26 full-length sequences of the adenovirus hexon gene were cloned and sequenced. Phylogenetic trees and sequence alignments revealed that all 26 strains belonged to subgroup C serotype 4 and shared some consistent molecular characteristics that showed only 9 mutations without amino acid (AA) deletions. Eight sites were located in L1 and one in L2. To determine whether the complete hexon gene was under positive selection pressure, site-by-site analysis was performed to identify specific codons that underwent evolutionary selection. Analysis identified 7 positively selected codons in L1 (AA 164, 168, 195, and 243) and L2 (AA 379, 402, and 408). The other 2 sites (AA 140 and 680) were located in P1 and P2, respectively. The results reveal that hexon loops L1 and L2 are hypervariable regions. Moreover, elucidation of viral distribution indicated that the liver is a major target organ, and FAdV-4 is a pantropic virus. In summary, FAdV-4 has been identified as an epidemic strain, and viral evolution is ongoing; thus, continuous surveillance of this virus will contribute to the control of future epidemics. [ABSTRACT FROM AUTHOR]

Summary: One hundred and five fowl adenovirus (FAdV) strains were isolated in China from 2015 to 2016 from poultry with inclusion body hepatitis (IBH) and hydropericardium syndrome (HPS). Polymerase chain reactions determined that 68 were FAdV species C, five were FAdV species D, two were FAdV species E, and 30 contained two or more different FAdV strains. A phylogenetic analysis showed that the isolated FAdV strains clustered into three major groups: FAdV‐C, FAdV‐D and FAdV‐E. Based on a hexon gene sequencing analysis, these viruses were genetically related to FAdV‐4, FAdV‐7, FAdV‐8b and FAdV‐11, of which FAdV‐4 was dominant (93% of the strains). An epidemiological analysis showed that FAdVs had been circulating in broilers, domestic chickens, and layers, and co‐infections with other immunosuppressive pathogens, such as chicken infectious anaemia virus, Marek's disease virus and reticuloendotheliosis virus, were identified. To control FAdVs, strict biosecurity protection measures are necessary, and a continued surveillance of FAdVs is needed to increase our understanding of the epidemiology of the viruses that are associated with IBH and HPS. [ABSTRACT FROM AUTHOR]

Despite the efficiency of deep brain stimulation (DBS) in the treatment of Parkinson’s disease (PD), the respective systems need to be further optimized. The lack of accurate PD-related quantitative biomarkers limits the improvement of adaptive DBS (aDBS) systems. Now, most DBS devices are open-loop sets with fixed stimulation parameters, which prevents them from coping with movement fluctuations and rapid changes of the symptoms. At the same time, ample evidence has shown that abnormal oscillations in the composition of local field potential (LFP) signals recorded in PD patients can reflect, to a certain extent, the crucial symptoms of the desease. Therefore, acquisition of LFP signals, extraction of abnormal oscillations, and acquisition of indicative biomarkers is the core technical issue with respective to the aDBS systems. Here, we review the current feature extraction methods in PD, summarize results of the latest research, analyze the difficulties of extracting the quantitative biomarkers, and discuss the developmental trend of feature extraction for aDBS. [ABSTRACT FROM AUTHOR]

In order to validate the evaluated nuclear data for 238 U, leakage neutron spectra from pure 238 U slab samples of different thicknesses bombarded with 14.8 MeV D-T neutrons were measured at 60 ° (for 10 cm × 10 cm × 2 cm, 10 cm × 10 cm × 5 cm, 10 cm × 10 cm × 11 cm samples) and 120 ° (for 10 cm × 10 cm × 5 cm, 10 cm × 10 cm × 11 cm samples) respectively. The measurement was performed at China Institute of Atomic Energy using time-of-flight method. Monte Carlo simulations were carried out by MCNP-4C code combined with various evaluated nuclear data libraries, namely, ENDF/B-VII.1, JENDL-4.0, CENDL-3.1, JEFF-3.2 and TENDL-2015. The experimental results were compared with the corresponding calculated ones, and the calculation-to-experiment ratio (C/E) which indicates the agreement between them was obtained. The results show that the JENDL4.0 fitted the experimental data best. [ABSTRACT FROM AUTHOR]

• A field measurement of two typical UHV transmission towers is implemented by performing a structural health monitoring (SHM) system. • The fast Bayesian FFT method is applied for the dynamic analysis of the UHV transmission towers. • The reconstructed signals are used to validate the accuracy approximation of the Bayesian approach. • The results can be a reference for wind resistance design of the UHV transmission towers. The ultra-high-voltage (UHV) transmission tower is currently the most advanced transmission tower in the world. The UHV transmission line is mainly composed of tangent towers and tension towers with different structural forms. This is interesting from a dynamic point of view, since the two typical structures may behave differently in terms of dynamic characteristics. In this study, a comparative study on operational modal analysis (OMA) of these two typical UHV transmission towers under ambient test is carried out by a fast Bayesian FFT method. Prior to the test, the selected frequency bands of modeling are determined by the sensitivity analysis. A structural health monitoring (SHM) system is installed on the towers during the maintenance period to monitor the acceleration response. The dynamic properties of the towers are obtained by the recently developed fast Bayesian FFT method and compared, the accuracy approximation of the Bayesian approach is verified by frequency domain information reconstruction. Furthermore, the damping ratio results as well as other voltage levels are compared with different nations codes. It is found that the stiffness of the tension tower is relatively higher than that of the tangent tower. The first-mode damping ratio results of tower in all directions exceeds 2.59% and the vertical cross-arm direction of tension tower reaches 4.54%. The research results can provide a reference for the wind resistance design for UHV transmission tower, and can be used in model updating in the future works. [ABSTRACT FROM AUTHOR]

We introduce an extended SEIR infectious disease model with data assimilation for the study of the spread of COVID-19. In this framework, undetected asymptomatic and pre-symptomatic cases are taken into account, and the impact of their uncertain proportion is fully investigated. The standard SEIR model does not consider these populations, while their role in the propagation of the disease is acknowledged. An ensemble Kalman filter is implemented to assimilate reliable observations of three compartments in the model. The system tracks the evolution of the effective reproduction number and estimates the unobservable subpopulations. The analysis is carried out for three main prefectures of Japan and for the entire country of Japan. For these four communities, our estimated effective reproduction numbers are more stable than the corresponding ones estimated by a different method (Toyokeizai). We also perform sensitivity tests for different values of some uncertain medical parameters, like the relative infectivity of symptomatic/asymptomatic cases. The regional analysis results suggest the decreasing efficiency of the states of emergency. [ABSTRACT FROM AUTHOR]

Aim To examine the association of cutaneous nevi with Type 2 diabetes risk. Methods We prospectivly examined the associations between nevus count and risk of Type 2 diabetes among 26 240 men (1988-2010) from the Health Professionals Follow-up Study and 67 050 women (1986-2010) from the Nurses' Health Study. Information on the numbers of cutaneous nevi on arms at baseline and incident cases of Type 2 diabetes was collected using validated questionnaires. Results During 1 879 287 person-years of follow-up, we documented 9040 incident cases of Type 2 diabetes. After adjustment for age, BMI and other diabetes risk factors, greater number of nevi was associated with higher risk of Type 2 diabetes. Multivariable-adjusted hazard ratios for <1, 1-5, 6-14 and ≥15 nevi were 1.00 (reference), 1.02 (95% CI 0.93, 1.13), 1.08 (95% CI 0.88, 1.34) and 1.57 (95% CI 1.15, 2.15), respectively, for men ( P for linear trend = 0.01), and 1.00 (reference), 1.07 (95% CI 1.02, 1.13), 0.98 (95% CI 0.87, 1.10), and 1.25 (1.01, 1.54), respectively, for women ( P for linear trend = 0.05). This positive association remained consistent across subgroups stratified by age, BMI, multivitamin use, smoking status, alcohol, physical activity, history of hypercholesterolaemia, family history of diabetes, history of hypertension and menopausal status (in women). Conclusions Cutaneous nevus count may represent a novel marker for development of Type 2 diabetes, suggesting a possible unique melanocytic nevus-related mechanism in the pathogenesis of Type 2 diabetes. Further studies are warranted to confirm the findings and to investigate the underlying mechanisms. [ABSTRACT FROM AUTHOR]

We study the nonlinear dynamics behaviours of a rigid rotor supported by magnetic bearings. In particular, we consider the effect of rotor unbalanced mass and geometric coupling. Existing works in literature have mostly focused on a single value of parameter or a smaller range of the nonlinearities introduced by rotor imbalance and geometric coupling. This is partly due to the use of a linear PD controller which limits the system performance. In this paper, we use a nonlinear PD controller by adopting a time varying stiffness term. The control gains are chosen according to the stability chart for a Mathieu's equation. Consequently, we observe a delay in the onset of bifurcation indicating an improved rotor performance. [ABSTRACT FROM AUTHOR]

In the cold rolling process, the expansion and coalescence of micro-defects can make steel sheet quality descend and create edge crack in the steel sheet. And the edge crack can cause the strip rupture completely. In this research, the cohesive zone model (CZM) was used to analyse the initiation and propagation of edge crack in the cold rolling process with the non-reversing two-high mill. A bi-linear traction-separation law was utilized which is primarily given by the CZM parameters including the cohesive stress, T, and the cohesive energy, Γ. Compared with other popular models such as the Gurson-Tvergaard-Needleman (GTN) model, the CZM presents certain advantages because it requires a smaller number of parameters to be defined. Comparison results of the experiments and simulation illustrated that the CZM can provide accurate prediction for the propagation of edge crack in the cold rolling process. Parametric analysis was carried out and showed that the extent of the crack propagation increases with the increasing of the reduction ratio. [ABSTRACT FROM AUTHOR]

Expression quantitative trait loci (eQTL) analyses were applied in order to identify genetic factors that are relevant to the expression of a β-isoform Rubisco activase gene in maize, namely ZmRCAβ, in this study. During two years, a maize recombinant inbred line population was measured for ZmRCAβ expression levels at the grain filling stage. Based on a genetic map containing 916 molecular markers, we detected five eQTLs, namely qRCA2.1 on chromosome 2, and qRCA4.1, qRCA4.2, qRCA4.3, and qRCA4.4 on chromosome 4. These eQTLs explained the phenotypic variation ranging from 6.14% to 7.50% with the logarithm of the odd values ranging from 3.11 to 4.96. Based on the position of the eQTLs and ZmRCAβ on the chromosome, qRCA4.2 was inferred as a cis-eQTL and the remaining as a trans-eQTL, suggesting that a combination of both cis- and trans-acting elements might control ZmRCAβ expression. qRCA4.2, qRCA4.3, and qRCA4.4 were repeatedly detected during two years. [ABSTRACT FROM AUTHOR]