bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on the effect of sample shapes on the thermal shock behavior of ZrB2‐SiC‐Graphite sharp leading edge
Authors: Wang Anzhe , Liao Hailong , Zhang Tao , Jiang Minqi , Guo Fuxiao , Wang Yongzheng 
Published: February 2020

AbstractReliable evaluation of the thermal shock behavior of sharp leading edges (SLEs) was hampered by a lack of available experimental method in past decades. Herein, a novel water spraying method was utilized to investigate the shape effect of ZrB2‐SiC‐Graphite SLEs during thermal shock. Experimental results indicated that the critical failure temperature of ZrB2‐SiC‐Graphite SLEs was most sensitive to the wedge angle, which could lead to a dramatic attenuation by about 35% from 12° to 9°, and was relatively little affected by the tip radius of curvature and the thickness. Simulation results further revealed that the decay of critical failure temperature was mainly due to the significant stress concentration caused by the reduction of wedge angle. Scanning electron microscopy observation proved that cracks tend to bypass graphite flakes due to their weak interfacial bonding, while branching always occurred when encountering hard phases or inclusions.
Controlled Covalent Functionalization of 2 H‐MoS2 with Molecular or Polymeric Adlayers
Authors: Quirós‐Ovies Ramiro , Vázquez Sulleiro Manuel , Vera‐Hidalgo Mariano , Prieto Javier , Gómez I. Jénnifer , Sebastián Víctor , Santamaría Jesús , Pérez Emilio M. 
Published: February 2020

AbstractMost air‐stable 2D materials are relatively inert, which makes their chemical modification difficult. In particular, in the case of MoS2, the semiconducting 2 H‐MoS2 is much less reactive than its metallic counterpart, 1T‐MoS2. As a consequence, there are hardly any reliable methods for the covalent modification of 2 H‐MoS2. An ideal method for the chemical functionalization of such materials should be both mild, not requiring the introduction of a large number of defects, and versatile, allowing for the decoration with as many different functional groups as possible. Herein, a comprehensive study on the covalent functionalization of 2 H‐MoS2 with maleimides is presented. The use of a base (Et3N) leads to the in situ formation of a succinimide polymer layer, covalently connected to MoS2. In contrast, in the absence of base, functionalization stops at the molecular level. Moreover, the functionalization protocol is mild (occurs at room temperature), fast (nearly complete in 1 h), and very flexible (11 different solvents and 10 different maleimides tested). In practical terms, the procedures described here allow for the chemist to manipulate 2 H‐MoS2 in a very flexible way, decorating it with polymers or molecules, and with a wide range of functional groups for subsequent modification. Conceptually, the spurious formation of an organic polymer might be general to other methods of functionalization of 2D materials, where a large excess of molecular reagents is typically used.
Dual Inhibition of Pyruvate Dehydrogenase Complex and Respiratory Chain Complex Induces Apoptosis by a Mitochondria‐Targeted Fluorescent Organic Arsenical in vitro and in vivo
Authors: Liu Yu‐Jiao , Fan Xiao‐Yang , Zhang Dong‐Dong , Xia Yin‐Zheng , Hu Yan‐Jun , Jiang Feng‐Lei , Zhou Fu‐Ling , Liu Yi 
Published: February 2020

AbstractBased on the potential therapeutic value in targeting mitochondria and the fluorophore tracing ability, a fluorescent mitochondria‐targeted organic arsenical PDT‐PAO‐F16 was fabricated, which not only visualized the cellular distribution, but also exerted anti‐cancer activity in vitro and in vivo via targeting pyruvate dehydrogenase complex (PDHC) and respiratory chain complexes in mitochondria. In details, PDT‐PAO‐F16 mainly accumulated into mitochondria within hours and suppressed the activity of PDHC resulting in the inhibition of ATP synthesis and thermogenesis disorder. Moreover, the suppression of respiratory chain complex I and IV accelerated the mitochondrial dysfunction leading to caspase family‐dependent apoptosis. In vivo, the acute promyelocytic leukemia was greatly alleviated in the PDT‐PAO‐F16 treated group in APL mice model. Our results demonstrated the organic arsenical precursor with fluorescence imaging and target‐anticancer efficacy is a promising anticancer drug.
Sharp Extinction Rates for Fast Diffusion Equations on Generic Bounded Domains
Authors: Bonforte Matteo , Figalli Alessio 
Published: February 2020

We investigate the homogeneous Dirichlet problem for the fast diffusion equation ut = Δum, posed in a smooth bounded domain Ω ⊂ ℝN, in the exponent range ms = (N − 2)+/(N + 2) < m < 1. It is known that bounded positive solutions extinguish in a finite time T > 0, and also that they approach a separate variable solution u(t, x) ∼ (T − t)1/(1 − m)S(x) as t → T−, where S belongs to the set of solutions to a suitable elliptic problem and depends on the initial datum u0. It has been shown recently that v(x, t) = u(t, x) (T − t)−1/(1 − m) tends to S(x) as t → T−, uniformly in the relative error norm. Starting from this result, we investigate the fine asymptotic behavior and prove sharp rates of convergence for the relative error. The proof is based on an entropy method relying on an (improved) weighted Poincaré inequality, which we show to be true on generic bounded domains. Another essential aspect of the method is the new concept of “almost‐orthogonality,” which can be thought of as a nonlinear analogue of the classical orthogonality condition needed to obtain improved Poincaré inequalities and sharp convergence rates for linear flows. © 2019 Wiley Periodicals, Inc.
Computation of Electromagnetic Properties of Molecular Ensembles
Authors: Fernandez‐Corbaton Ivan , Beutel Dominik , Rockstuhl Carsten , Pausch Ansgar , Klopper Wim 
Published: February 2020

AbstractWe outline a methodology for efficiently computing the electromagnetic response of molecular ensembles. The methodology is based on the link that we establish between quantum‐chemical simulations and the transfer matrix (T‐matrix) approach, a common tool in physics and engineering. We exemplify and analyze the accuracy of the methodology by using the time‐dependent Hartree‐Fock theory simulation data of a single chiral molecule to compute the T‐matrix of a cross‐like arrangement of four copies of the molecule, and then computing the circular dichroism of the cross. The results are in very good agreement with full quantum‐mechanical calculations on the cross. Importantly, the choice of computing circular dichroism is arbitrary: Any kind of electromagnetic response of an object can be computed from its T‐matrix. We also show, by means of another example, how the methodology can be used to predict experimental measurements on a molecular material of macroscopic dimensions. This is possible because, once the T‐matrices of the individual components of an ensemble are known, the electromagnetic response of the ensemble can be efficiently computed. This holds for arbitrary arrangements of a large number of molecules, as well as for periodic or aperiodic molecular arrays. We identify areas of research for further improving the accuracy of the method, as well as new fundamental and technological research avenues based on the use of the T‐matrices of molecules and molecular ensembles for quantifying their degrees of symmetry breaking. We provide T‐matrix‐based formulas for computing traditional chiro‐optical properties like (oriented) circular dichroism, and also for quantifying electromagnetic duality and electromagnetic chirality. The formulas are valid for light‐matter interactions of arbitrarily‐high multipolar orders.
Photoinduced Release of DNA‐Binding Ligands from the [4+4] Dimers of Benzo[b]quinolizinium and Anthracene Derivatives
Authors: Berdnikova Daria V. , Heider Josef , Ihmels Heiko , Sewald Norbert , Pithan Phil M. 
Published: February 2020

AbstractIt is demonstrated with four representative examples that the dimers of benzo[b]quinolizinium, dibenzo[b,g]quinolizinium and anthracene derivatives may be used as a source to release the DNA‐binding monomers upon irradiation in the presence of DNA, as determined by monitoring the reaction with absorption and CD spectroscopy. Specifically, the dimers of the benzo[b]quinolizinium turned out to be suitable for this purpose as the ligand is formed rapidly in the presence of DNA and subsequently intercalates into the nucleic acid. In combination with the promising biological properties and bioanalytical value of benzo[b]quinolizinium derivatives, this approach may be used as a general method to generate these functional dyes with spatio‐temporal control.
Formation of solitary structures and envelope solitons in electron acoustic wave in inner magnetosphere plasma with suprathermal ions
Authors: Sarkar Jit , Chandra Swarniv , Goswami Jyotirmoy , Ghosh Basudev 
Published: February 2020

AbstractThe propagation of electron acoustic solitary waves is investigated in magnetized two‐temperature electron plasma with supra‐thermal ion. By using the reductive perturbation technique, the Korteweg de‐Vries (KdV) equation is derived. Later solving this equation, a solitary wave solution has been derived. These are mainly in astrophysical plasmas where changes of local charge density, temperature, and energy of particles produce considerable effects on the plasma system. The effects of supra‐thermality, density, and Mach number on solitary structures are studied in detail. The results show that the supra‐thermal index (κ) and ion to electron temperature ratio (σ) alters the regime where solitary waves may exist. While studying the solitary profile for different parametric variation some interesting conclusion can be drawn; it is shown that the solitary profile becomes flatter. This can be due to the thermal energy associated with the hot electrons. However, with the increase in ion density with respect to the cold electrons' density, the solitary waves become steeper and sharper. This is due to the comparatively heavier mass of ions. The density of cold electron also increases the solitary structures in a similar manner. The higher the density of cold electrons, sharper will be the profile. The above findings will be helpful in understanding many astrophysical phenomena and data obtained by space missions. For a further study, we keep the investigation of the formation of other kinds of stationary structures like shocks, double layers, etc.
Experimental study of low‐concentration gas explosion in large‐scale pipeline
Authors: Li Lei , Zhang Zhigang , Liu Peng , Wang Kequan , Zhang Jun , Li Xuelong 
Published: February 2020

AbstractLow‐concentration gas is one of the most realistic and reliable supplementary or alternative energy sources of conventional natural gas, which has a wide range of applications. However, this gas is flammable and explosive during pipeline transportation and easily causes an explosion. In order to achieve safe transmission, the explosion characteristics and propagation law of low‐concentration gas are systematically studied through a large‐scale pipeline experimental system. We found that the peak pressure of low‐concentration gas explosion in pipeline has a quadratic function relationship with the propagation distance. Moreover, the peak pressure of gas explosion initially decreases from the explosion source, and then a turning point appears after a certain distance of propagation, which is followed by a sharp increase of peak pressure of gas explosion. The explosion pressure becomes maximum at the outlets of a pipeline. The arrival time of explosion flame is logarithmically relevant to propagation distance, while the speed of flame propagation gradually increases along with the increase of propagation distance. The flame propagation is faster at the exit point. In addition, the diameter of pipeline has also an important influence on the explosion propagation process of low‐concentration gas. So, the larger the diameter, the higher the explosion pressure. The explosion pressure of DN700 pipeline is obviously higher than that of DN500, and the explosion pressure rises faster; the speed of flame propagation of gas explosion in DN700 pipeline is also higher than that in DN500 pipeline. This study provides a theoretical reference for the prevention and control of explosion accidents in low‐concentration gas pipelines.
Enhanced performance analysis of a hybrid spectrum sliced‐wavelength division multiplexing‐mode division multiplexing‐orthogonal frequency division multiplexing based radio‐over‐free space optics
Authors: Grover Amit , Sheetal Anu , Dhasarathan Vigneswaran 
Published: February 2020

AbstractIn this work, we report the use of self‐phase modulation in a high nonlinearity fiber for super continuum frequency generation which is spectrum‐sliced using a demultiplexer. Four channels (193‐193.225 THz) are sliced with 75 GHz channel spacing. Each wavelength channel transports two distinct sub‐channels with 20 Gbit/s‐40 GHz data rate over different Laguerre Gaussian spatial modes (LG02 and LG03) using the proposed hybrid spectrum sliced‐wavelength division multiplexing‐mode division multiplexing based orthogonal frequency division multiplexing‐radio‐over‐free space optics link. The performance of the proposed link is investigated using numerical simulations. 160 Gbit/s‐320 GHz data is transmitted at 20 km for clear conditions with reliable performance. We have also analyzed the link performance under different level of fog weather. Further to maximize the link reach, we have proposed an enhanced detection at the receiver terminal. The results of numerical investigation of the link show an improvement of 40 dB in signal‐to‐noise ratio and received power under different weather conditions using the proposed detection technique.
Constructal design of longitudinally finned tubes cooled by forced convection
Authors: Yehia Abbas Noor , Waheed Mustafa Ahmed , Kheir Aldeen Abbas Asker Mohammed 
Published: February 2020

AbstractThe constructal design method is used in the present study to find the configuration of longitudinally finned tubes cooled by forced convection. The finned tubes are arranged in parallel inside a fixed two‐dimensional domain. Two degrees of freedom inside the domain are considered for the design. The first degree of freedom is the tube‐to‐tube spacing, and the second is the length of the longitudinal fin. For both these degrees of freedom, a three‐fin position inside the domain is considered. The fin is placed in the front, back, and front and back of the tube in the first, second, and third positions, respectively. Maximization of the heat flow density (heat transfer/volume) from the finned tubes to the cold cross flow is the objective function of the present study. For the three fin positions, the constant pressure difference between the upstream and the downstream drives the cross flow. The dimensionless continuity, momentum, and energy equations for two dimensional, steady, and incompressible flows are solved by discretizing it according to the finite volume method. The thermal condition of the fins and the tubes is constant surface temperature. The dimensionless pressure drop known as Bejan number is varied in the range of 103 ≤ Be ≤ 105. The fin length is changed from Lf = 0 (unfinned tube) to Lf = 0.2, 0.4, and 0.4. The tubes are cooled by air (Prandtl number = 0.71). The results illustrated that for the considered Bejan numbers and fin positions, the spacing between the unfinned and the finned tubes can be adjusted to optimal spacing such that the heat flow from the tubes to the coolant is maximum.
Non‐coenzyme role of vitamin B1 in RANKL‐induced osteoclastogenesis and ovariectomy induced osteoporosis
Authors: Ma Qinyu , Liang Mengmeng , Wang Yaxi , Ding Ning , Wu Yutong , Duan Lianli , Yu Tao , Lu Yanzhu , Xu Jianzhong , Kang Fei , Dou Ce 
Published: February 2020

AbstractVitamins B are co‐enzymes participating in energy metabolic pathways. While some vitamins B are known affecting bone homeostasis, the effects of vitamin B1 (thiamine) on bone health remains unclear. In our study, we used cell counting kit‐8, tartrate‐resistant acid phosphatase stain, actin cytoskeleton stain, and pit formation assay to evaluate the effect of thiamine on osteoclast differentiation, formation, and function, respectively. Then we used dichloro‐dihydro‐fluorescein diacetate assay to investigate reactive oxygen species (ROS) generation and removal. Osteoporosis model by ovariectomy was established for animal experiments. We found that thiamine had inhibitory effect on osteoclast differentiation. And its inhibitory role on osteoclast differentiation is in a dose‐dependent way. Mechanistically, ThDP suppresses intracellular ROS accumulation and unfolded protein response signaling during osteoclastogenesis via inhibiting Rac‐Nox1/2/4 and intracellular inositol‐requiring protein‐1α/X‐box‐binding protein pathways, respectively. Osteoporotic mice treated with thiamine rich dietary showed better bone strength relative to thiamine deficient dietary. Our study explored the non‐coenzyme inhibitory functions of B1 vitamin in receptor activator of nuclear factor κB ligand induced osteoclastogenesis and uncovered the significance of B1 vitamin in bone health.
Interaction between miRNAs and signaling cascades of Wnt pathway in chronic lymphocytic leukemia
Authors: Bhattacharya Manojit , Sharma Ashish Ranjan , Sharma Garima , Patra Bidhan Chandra , Lee Sang‐Soo , Chakraborty Chiranjib 
Published: February 2020

AbstractChronic lymphocytic leukemia (CLL), a severe problem all over the world and represents around 25% of all total leukemia cases, is generating the need for novel targets against CLL. Wnt signaling cascade regulates cell proliferation, differentiation, and cell death processes. Thus, any alteration of the Wnt signaling pathway protein cascade might develop into various types of cancers, either by upregulation or downregulation of the Wnt signaling pathway protein components. In addition, it is reported that activation of the Wnt signaling pathway is associated with the transcriptional activation of microRNAs (miRNAs) by binding to its promoter region, suggesting feedback regulation. Considering the protein regulatory functions of various miRNAs, they can be approached therapeutically as modulatory targets for protein components of the Wnt signaling pathway. In this article, we have discussed the potential role of miRNAs in the regulation of Wnt signaling pathway proteins related to the pathogenesis of CLL via crosstalk between miRNAs and Wnt signaling pathway proteins. This might provide a clear insight into the Wnt protein regulatory function of various miRNAs and provide a better understanding of developing advanced and promising therapeutic approaches against CLL.
Comparison of the serum level of interleukin‐4 in patients with brucellosis and healthy controls
Authors: Eini Peyman , Majzoobi Mohammad Mahdi , Ghasemi Basir Hamid Reza , Moosavi Zahra , Moradi Abbas 
Published: February 2020

AbstractIntroductionEvaluation of cytokines such as interleukin‐4 (IL‐4) can be an important tool in examining immune responses to brucellosis. Also, determining the response rate to treatment is necessary for controlling and eradicating of disease. The review of previous studies reveals contradictory results that require further research in this regard. The aim of this study was to compare the serum level of IL‐4 in patients with brucellosis and healthy controls.Material and MethodsIn this descriptive‐analytical study for comparison of two groups, a total of 165 participants, including 83 patients with brucellosis and 82 non‐infected people, were evaluated after matching of sex and age in Hamadan (northwest of Iran) in 2017 and the serum level of IL‐4 was compared by ELISA method. The collected data were analyzed by SPSS software version 21 at 95% significant level.ResultsMean of age in the case and control groups were 50.25 ± 16.01 and 43.26 ± 15.6 years, respectively. The serum levels of IL‐4 in the case and control groups were 1.42 ± 0.51 pg/mL and 1.31 ± 1.02 pg/mL, respectively. Based on the non‐parametric Mann‐Whitney test, the IL‐4 level was significantly higher in the case group, compared with the control (P < .001), but no statistically significant relationship was found between serum levels of IL‐4 with age, sex, and serologic titers of Wright and 2ME.ConclusionIn patients with brucellosis, the level of IL‐4 increases independently of the duration and severity of the disease, which indicates the role of this cytokine of immune system in this infectious disease.
Isometric subgraphs for Steiner distance
Authors: Weißauer Daniel 
Published: February 2020

AbstractLet G be a connected graph and a length‐function on the edges of G. The Steiner distance sdG(A) of A ⊆ V(G) within G is the minimum length of a connected subgraph of G containing A, where the length of a subgraph is the sum of the lengths of its edges. It is clear that every subgraph H ⊆ G, endowed with the induced length‐function ℓ∣E(H), satisfies sdH(A) ≥ sdG(A) for every A ⊆ V(H). Given an integer k ≥ 2, we call H ⊆ G k‐isometric in G if equality is attained for every A ⊆ V(H) with ∣A∣ ≤ k. A subgraph is fully isometric if it is k‐isometric for every . It is easy to construct examples of graphs H ⊆ G such that H is k‐isometric, but not (k + 1)‐isometric, so this defines a strict hierarchy of properties. We are interested in situations in which this hierarchy collapses in the sense that if H ⊆ G is k‐isometric, then H is already fully isometric in G. Our first result of this kind asserts that if T is a tree and T ⊆ G is 2‐isometric with respect to some length‐function ℓ, then it is fully isometric. This fails for graphs containing a cycle. We then prove that if C is a cycle and C ⊆ G is 6‐isometric, then C is fully isometric. We present an example showing that the number 6 is indeed optimal. We then develop a structural approach toward a more general theory and present several open questions concerning the big picture underlying this phenomenon.
Trabecular bone score, a new bone quality index, is associated with severe periodontitis
Authors: Niramitchainon Chutinun , Mongkornkarn Sanutm , Sritara Chanika , Lertpimonchai Attawood , Udomsak Artit 
Published: February 2020

AbstractBackgroundThe association between systemic bone loss and periodontitis remains unresolved; and the trabecular bone score (TBS) is a new index for assessing decreased bone quality. Therefore, this cross‐sectional study investigated the association between TBS and severe periodontitis.MethodsEight hundred and five Thai participants, aged 30 to 82 years, underwent bone quality assessment. Their mean TBS was calculated from dual‐energy X‐ray absorptiometry images at the L1 to L4 lumbar spine using TBS software. Each participant was classified as normal, partially degraded, or degraded TBS. Full‐mouth periodontal examinations determined plaque score, probing depth, clinical attachment level (CAL), and the number of remaining teeth. The participants were classified as non‐severe or severe periodontitis. Differences in periodontal parameters between the TBS groups were analyzed using one‐way ANOVA. The association between TBS and severe periodontitis was assessed with multivariate binary logistic regression. For severe periodontitis, the additive interaction between TBS and oral hygiene status was also analyzed.ResultsThe mean CAL was 0.9‐mm higher in the degraded TBS group compared with the normal TBS group. Degraded TBS was associated with severe periodontitis with an adjusted odds ratio (OR) of 2.10 (95% confidence interval [CI] = 1.03 to 4.26). The combination of degraded TBS and plaque score ≥80% increased the adjusted OR to 5.71 (95% CI = 1.15 to 28.43).ConclusionsDegraded TBS is associated with severe periodontitis and has a synergistic effect with poor oral hygiene, suggesting monitoring decreased bone quality and good oral hygiene for promoting the periodontal‐systemic health of these individuals.