bluuebunny/crossref_metadata_2025 huggingface dataset:
Solar energy harvesting with ultra-broadband metamaterial absorber
Authors: Bagmanci Mehmet , Karaaslan Muharrem , Unal Emin , Akgol Oguzhan , Bakır Mehmet , Sabah Cumali
Published: March 2019

In this study, a novel metamaterial absorber (MA) is designed and numerically demonstrated for solar energy harvesting. The structure is composed of three layers with different thicknesses. The interactions of three layers bring about the plasmonic resonances. Although the main operation frequency of the structure is chosen between 430 and 770 THz, which is the visible light regime, the proposed structure is also investigated in the ultra-violet (UV) region. One can see from the results that the proposed structure carries nearly perfect absorption capacity that is more than 91% at the whole visible light spectrum. The proposed structure even has the absorption capacity of 99% between 556 and 657 THz. In addition, the designed MA is also investigated in terms of its polarization and angle independency. Results show that the proposed structure is independent from the polarization and incident angles. Lastly, the designed structure can be considered to be used in solar energy applications as a harvester since it has an ultra-broadband absorption characteristic in visible light regime.
Fixed-time cluster synchronization in directed community networks with diverse coupling and different-order nodes
Authors: Zhou Feilong , Zhao Yi , Cai Shuiming
Published: March 2019

In this paper, fixed-time cluster synchronization of directed community networks (DCNs) with diverse coupling and different-order nodes is explored. For the DCN model, the inherent dynamics and state dimensions of the nodes in different communities can be nonidentical, and moreover, the interactive nodes can differ in their types of connections in different communities and the connections between any pair of different communities can be nonidentical as well. Two types of control strategies, state feedback control and adaptive feedback control, are adopted to force such DCNs to realize cluster synchronization in fixed-time. By utilizing reduction to absurdity, some sufficient conditions ensuring the fixed-time cluster synchronization are derived for the proposed two control schemes. Moreover, it is revealed theoretically that our estimated settling time is more precise and less conservative than that presented in the previous researches. Finally, the validity of the obtained fixed-time cluster synchronization criteria is verified via numerical simulations.
Nanowire-type plasmonic waveguides as strong and tunable optical tweezers
Authors: Yang Shu , Zhao Kang
Published: March 2019

A series of nanowire-type plasmonic waveguides are proposed. The mode properties of these waveguides and their dependences on various geometry parameters are studied. It is shown that they can generate deep subwavelength confinement and long-range propagation simultaneously. Moreover, the optical forces exerted on dielectric nanoparticles by these waveguides are calculated. It is found that the optical trapping forces are very strong, and that their distribution can be effectively regulated by certain geometry parameters. Using these features, strong and tunable near-field optical tweezers can be designed.
A Multiband, Spectrally-Efficient Impulse Radio Transmitter Design with Low-Complexity CMOS Pulse Generator for IEEE 802.15.4a Application
Authors: Saoudi Hanen , Ghariani Hamadi , Lahiani Mongi
Published: March 2019

A novel multiband impulse radio ultra-wideband (MB-IR-UWB) transmitter with an energy-efficient and low-complexity pulse generator design technique compliant with the IEEE 802.15.4a standard is investigated in this paper. This transmitter is made up of a new differential narrow triangular pulse generator, a new multiband voltage-controlled oscillator (VCO), an active mixer and a variable-gain power amplifier (PA). It operates at 14 UWB bands and generates an output signal with the duration of 3[Formula: see text]ns, more than 500[Formula: see text]MHz of channel bandwidth and more than 20[Formula: see text]dB of sidelobe suppression, while achieving an average energy efficiency of 51.36 pJ/pulse from 1.4-V supply. Improving spectral flexibility and worldwide compliance is the major contribution brought by this paper to make this circuit as a multifunction wireless device well suited for low-cost, low-power multiband applications.
To see the invisible: Image of the event horizon within the black hole shadow
Authors: Dokuchaev Vyacheslav
Published: March 2019

How the supermassive black hole SgrA* in the Milky Way Center looks like for a distant observer? It depends on the black hole highlighting by the surrounding hot matter. The black hole shadow (the photon capture cross-section) would be viewed if there is a stationary luminous background. The black hole event horizon is invisible directly (per se). Nevertheless, a more compact (with respect to black hole shadow) projection of the black hole event horizon on the celestial sphere may be reconstructed by detecting the highly redshifted photons emitted by the nonstationary luminous matter plunging into the black hole and approaching the event horizon. It is appropriate to call this reconstructed projection of the event horizon on the celestial sphere for a distant observer as the “lensed event horizon image”, or simply the “event horizon image”. This event horizon image is placed on the celestial sphere within the position of black hole shadow. Amazingly, the event horizon image is a gravitationally lensed projection on the celestial sphere of the whole surface of the event horizon globe. As a result, the black holes may be viewed at once from both the front and back sides. The lensed event horizon image may be considered as a genuine silhouette of the black hole. For example, a dark northern hemisphere of the event horizon image is the simplest model for a black hole silhouette in the presence of a thin accretion disk.
INFLUENCE OF ARGON GAS AND COPPER THICKNESS ON THE OPTOELECTRONICAL AND STRUCTURAL PROPERTIES OF AlZnO/Cu/AlZnO THIN FILM
Authors: MOSHABAKI AREZOO , KADIVAR ERFAN , FIROOZIFAR ALIREZA
Published: March 2019

AlZnO/Cu/AlZnO multilayer films were deposited on glass substrate by RF magnetron sputtering of AlZnO target and DC magnetron sputtering of copper target at room temperature. Subsequently, some of the samples have been annealed for 20[Formula: see text]min in vacuum or air at 350∘C for 20[Formula: see text]min. The optical, surface morphology, crystal structure, and electrical characteristics have been examined by spectrophotometry, atomic force microscope, field emission scanning electron microscopy, X-ray diffraction, and four-point probe as a function of argon gas flux, and copper thickness. It is found that the crystallinity of AlZnO and Cu layers improve by increasing the thickness of copper film. We have found that the maximum value of figure of merit is related to the copper thickness of 8[Formula: see text]nm. Finally, the AlZnO/Cu/AlZnO thin films have been processed with alumina polishing solution by ultrasonic method. The optimum process parameters have been obtained to provide a very smooth surface.
A study of enhanced power graphs of finite groups
Authors: Zahirović Samir , Bošnjak Ivica , Madarász Rozália
Published: March 2019

The enhanced power graph [Formula: see text] of a group [Formula: see text] is the graph with vertex set [Formula: see text] such that two vertices [Formula: see text] and [Formula: see text] are adjacent if they are contained in the same cyclic subgroup. We prove that finite groups with isomorphic enhanced power graphs have isomorphic directed power graphs. We show that any isomorphism between undirected power graph of finite groups is an isomorphism between enhanced power graphs of these groups, and we find all finite groups [Formula: see text] for which [Formula: see text] is abelian, all finite groups [Formula: see text] with [Formula: see text] being prime power, and all finite groups [Formula: see text] with [Formula: see text] being square-free. Also, we describe enhanced power graphs of finite abelian groups. Finally, we give a characterization of finite nilpotent groups whose enhanced power graphs are perfect, and we present a sufficient condition for a finite group to have weakly perfect enhanced power graph.
Distance spectral radius of unicyclic graphs with fixed maximum degree
Authors: Huang Hezan , Zhou Bo
Published: March 2019

The distance spectral radius of a connected graph is the largest eigenvalue of its distance matrix. For integers [Formula: see text] and [Formula: see text] with [Formula: see text], we prove that among the connected graphs on [Formula: see text] vertices of given maximum degree [Formula: see text] with at least one cycle, the graph [Formula: see text] uniquely maximizes the distance spectral radius, where [Formula: see text] is the graph obtained from the disjoint star on [Formula: see text] vertices and path on [Formula: see text] vertices by adding two edges, one connecting the star center with a path end, and the other being a chord of the star.
Fat points, partial intersections and Hamming distance
Authors: Cooper Susan M. , Guardo Elena
Published: March 2019

We use two main techniques, namely, residuation and separators of points, to show that the Hilbert function of a certain fat point set supported on a grid complete intersection is the same as the Hilbert function of a reduced set of points called a partial intersection. As an application, we answer a question of Tohǎneanu and Van Tuyl which relates the minimum Hamming distance of a special linear code and the minimum socle degree of the associated fat point set.
Biwarped product submanifolds of complex space forms
Authors: Khan Meraj Ali , Khan Kamran
Published: March 2019

The class of biwarped product manifolds is a generalized class of product manifolds and a special case of multiply warped product manifolds. In this paper, biwarped product submanifolds of the type [Formula: see text] embedded in the complex space forms are studied. Some characterizing inequalities for the existence of such type of submanifolds are derived. Moreover, we also estimate the squared norm of the second fundamental form in terms of the warping function and the slant function. This inequality generalizes the result obtained by Chen in [B. Y. Chen, Geometry of warped product CR-submanifolds in Kaehler manifolds I, Monatsh. Math. 133 (2001) 177–195]. By the application of derived inequality, we compute the Dirichlet energies of the warping functions involved. A nontrivial example of these warped product submanifolds is provided.
A short note on tetracyclic graphs with extremal values of Randić index
Authors: Elumalai Suresh , Mansour Toufik
Published: March 2019

Let [Formula: see text] be a simple graph. The Randić index of [Formula: see text] is defined as the sum of [Formula: see text] over all edges [Formula: see text] of [Formula: see text], where [Formula: see text] denotes the vertex degree of [Formula: see text] in [Formula: see text]. Dehghan-Zadeh, Ashrafi and Habibi gave Tetracyclic graphs with extremal values of Randić index. We first point out that Theorem 1 is not completely correct and the number of nonisomorphic tetracyclic graphs on seven vertices given in Fig. 4 is incomplete and incorrect and in this short note, we present the correct version of it.
Almost Bézout rings and almost GCD-rings
Authors: El Khalfi Abdelhaq , Mahdou Najib
Published: March 2019

In this paper, we study the possible transfer of the property of being an [Formula: see text]-ring to trivial ring extensions and amalgamated algebras along an ideal. Also, we extend the notion of an almost GCD-domain to the context of arbitrary rings, and we study the possible transfer of this notion to trivial ring extensions and amalgamated algebras along an ideal. Our aim is to provide examples of new classes of commutative rings satisfying the above-mentioned properties.
Rethinking Incremental and Parallel Pointer Analysis
Authors: Liu Bozhen , Huang Jeff , Rauchwerger Lawrence
Published: March 2019

Pointer analysis is at the heart of most interprocedural program analyses. However, scaling pointer analysis to large programs is extremely challenging. In this article, we study incremental pointer analysis and present a new algorithm for computing the points-to information incrementally (i.e., upon code insertion, deletion, and modification). Underpinned by new observations of incremental pointer analysis, our algorithm significantly advances the state of the art in that it avoids redundant computations and the expensive graph reachability analysis, and preserves precision as the corresponding whole program exhaustive analysis. Moreover, it is parallel within each iteration of fixed-point computation. We have implemented our algorithm, IPA, for Java based on the WALA framework and evaluated its performance extensively on real-world large, complex applications. Experimental results show that IPA achieves more than 200X speedups over existing incremental algorithms, two to five orders of magnitude faster than whole program pointer analysis, and also improves the performance of an incremental data race detector by orders of magnitude. Our IPA implementation is open source and has been adopted by WALA.
Consensus Learning Control for Leader-Following Nonlinear Multiagent Systems with Control Delay
Authors: Deng Xiongfeng , Sun Xiuxia , Liu Shuguang
Published: March 2019

In this paper, the consensus tracking problem of leader-following nonlinear control time-delay multiagent systems with directed communication topology is addressed. An improved high-order iterative learning control scheme with time-delay is proposed, where the local information between agents is considered. The uniformly global Lipschitz condition is applied to deal with the nonlinear dynamics. Then, a sufficient condition is driven, which guarantees that all the following agents track the trajectory of leader. Also, the convergence of proposed control protocol is analyzed by the norm theory. Finally, two cases are provided to illustrate the validity of theoretical results.
Soft Tissue Sarcomas of the Thoracic Wall: More Prone to Higher Mortality, and Local Recurrence—A Single Institution Long-Term Follow-up Study
Authors: Soerensen Tine Rytter , Raedkjaer Mathias , Jørgensen Peter Holmberg , Hoejsgaard Anette , Safwat Akmal , Baad-Hansen Thomas
Published: March 2019

Objectives. This study aims to assess the impact of surgical margin and malignancy grade on overall survival (OS) and local recurrence free rate (LRFR) for soft tissue sarcomas (STS) of the thoracic wall. Methods. This retrospective cohort study identified 88 patients, diagnosed and treated surgically for a nonmetastatic STS located in the thoracic wall between 1995 and 2013, using the population based and validated Aarhus Sarcoma Registry and Danish Sarcoma Registry. The Kaplan-Meier method was used to estimate OS and LRFR. Multivariate Cox analyses were used to determine prognostic factors for OS and LRFR. Results. The 5-year OS was 55% (95% confidence interval (CI): 0.44-0.65) and 5-year LRFR was 77% (95% CI: 0.67-0.85). High malignancy grade and intralesional/marginal resection were identified as negative predictors for OS. High grade was the only prognostic factor associated with a lower LRFR. Conclusions. In this large, single institution, study tumor grade was the key predictor for OS and LRFR. Surgical margin only statistically significantly influenced mortality, not local recurrence.
Cryotherapy Reduced Postoperative Pain in Gynecologic Surgery: A Randomized Controlled Trial
Authors: Chumkam Apisada , Pongrojpaw Densak , Chanthasenanont Athita , Pattaraarchachai Junya , Bhamarapravatana Kornkarn , Suwannarurk Komsun
Published: March 2019

Objective. To examine the effectiveness of cryotherapy for reducing postoperative pain in patients who underwent exploratory laparotomy for gynecologic surgery. Materials and Methods. Patients who had indication for an exploratory laparotomy gynecologic procedure were selected by attending physicians to undergo abdominal surgery via low transverse skin incision. The participants were randomized into study and control groups with simple random sampling methods. Cold packs were applied at two hours after operation for 6 hours. The visual analog scale (VAS) score was recorded at two, 6, and 12 hours after operation. Result. One hundred cases were recruited and then divided into study and control groups equally. The mean age of both groups was 43 years. There was no difference in demographics data of both groups. Half of the participants in both groups underwent hysterectomies. At two hours after surgery, both groups had similar VAS scores. The study group had a lower VAS score at 6 and 12 hours after surgery than the control group with statistical difference. Morphine consumption within 24 hours after surgery in both the study and control groups was 2.8±3.4 and 3.0±4.4 mg, respectively, with no statistical difference. However the registration time of the first morphine requirement in the study group was statistically more prolonged than that of the control group. The lengths of hospital stay in both groups were similar. There was no complication reported in this study. Conclusion. Cryotherapy can reduce postoperative pain. In this presented study the patients who underwent gynecologic surgery had improved pain relief and prolonged time for the first dose of the analgesic drug.
SFDE: Shuffled Frog-Leaping Differential Evolution and Its Application on Cognitive Radio Throughput
Authors: Wang Hongbo , Zhen Xiaoxiao , Tu Xuyan
Published: March 2019

Differential Evolution (abbreviation for DE) is showing many advantages in solving optimization problems, such as fast convergence, strong robustness, and so on. However, when DE faces a complex target space, the diversity of its population will degenerate in a small scope; even sometimes it is premature to fall into the local minimum. All things contend in beauty in the world; a Shuffled Frog Leaping Algorithm (abbreviation for SFLA) has a strong global ability; unfortunately, its convergence speed is also slow. In order to overcome the shortcoming, this article suggests a Shuffled Frog-leaping Differential Evolution (abbreviation for SFDE) algorithm in a cognitive radio network, which combines Differential Evolution with Shuffled Frog Leaping Algorithm. This proposed method hikes its local searching for a certain number of subgroups, and their individuals join together and share their mutual information among different subgroups, which improves the population diversity and achieves the purpose of fast global search during the whole Differential Evolution. The SFDE is examined by 20 well-known numerical benchmark functions, and those obtained results are compared with four other related algorithms. The experimental simulation in solving the problem of effective throughput optimization for cognitive users shows that the proposed SFDE is effective.
The Agreement Rate between Radiographic Interpretation and Histopathologic Diagnosis of Jaw Lesions
Authors: Almazrooa Soulafa , Binmadi Nada O. , Khalifa Hanadi M. , Jadu Fatima M. , Jan Ahmed M. , Meisha Dalia E.
Published: March 2019

Background. To determine the agreement rate between histopathologic diagnosis and radiographic interpretation of jaw lesions.Methods. Cases with jaw pathologies that have diagnostically adequate histopathologic samples and radiographic examinations were reviewed retrospectively. Two board-certified oral and maxillofacial pathologists (OMFP) independently determined the histopathologic diagnosis, while two board-certified oral and maxillofacial radiologists (OMFR) determined the radiographic interpretations independently. Then the histopathologic diagnosis and the radiographic interpretation were compared for agreement.Results. A total of 104 cases (53% females) were included with a mean age of 31 years. The agreement rate between histopathologic diagnosis and radiographic interpretation was 49%. OMFP required OMFR consultations to reach a diagnosis in 16% of cases. The most commonly encountered lesions were by far odontogenic cysts of inflammatory origin and the agreement for this disease category was 49.1%. However, agreement rates were highest for the disease category of tumors (62.5%).Conclusion. The agreement rate between OMFP and OMFR was higher for tumors than cysts. Agreement rates between OMFP and OMFR improved with efficient consultation between the two disciplines.
Comparative Assessment on Selected Physicochemical Parameters and Antioxidant and Antimicrobial Activities of Honey Samples from Selected Districts of the Amhara and Tigray Regions, Ethiopia
Authors: Lewoyehu Mekuanint , Amare Meareg
Published: March 2019

The composition and properties of natural honeys differ with plant species on which the bees forage and the climatic conditions of the production areas. In Ethiopia, Amhara and Tigray are neighboring regions consisting of different agricultural activities and blossoms from different types of vegetations which may influence the natural composition and hence the properties of honey. So, the aim of the current study was to assess the quality of honey from selected districts of the two regions. In the study, 18 composited honey samples were collected from six selected districts and analyzed for selected physicochemical parameters and antioxidant and antimicrobial activities. The analyses of physicochemical parameters were carried out following standard procedures of IHC and QSAE. The antioxidant activity was determined by analyzing the RSA using DPPH while the antibacterial activities were determined by the agar well diffusion method. The moisture, ash content, electrical conductivity, pH, free acidity, reducing sugar, and sucrose content of the honey samples were found to be in the range 16.34 ± 0.26 to 19.83 ± 0.43 %, 0.08 ± 0.00 to 0.45 ± 0.03 %, 0.19 ± 0.00 to 0.89 ± 0.03 mS/cm, 3.79 ± 0.04 to 4.20 ± 0.01, 19.56 ± 1.13 to 38.11 ± 1.54 meq/kg, 62.10 ± 0.48 to 66.37 ± 0.20 %, and 1.35 ± 0.08 to 5.96 ± 0.10 %, respectively. The total phenolic content ranged from 1165.60 ± 23.45 to 1854.83 ± 10.47 mg/kg with antioxidant activity of 21.64 ± 0.26 to 36.12 ± 0.52 AEAC/100 g. The total phenolic contents showed strong correlation with RSA. Furthermore, all honey samples showed an antibacterial activity varying from 23.23 ± 0.12 to 28.84 ± 0.24 mm.
Flexural Strengthening and Rehabilitation of Reinforced Concrete Beam Using BFRP Composites: Finite Element Approach
Authors: Kadhim Asaad M. H. , Numan Hesham A. , Özakça Mustafa
Published: March 2019

Basalt fiber‐reinforced polymer (BFRP) is adopted widely in recent years in many countries to rehabilitate or strengthen structural elements such as reinforced concrete (RC) beams because it is cheap and it has stellar mechanical performance. By activating the finite element (FE) simulation, the present research submits an extensive study on the strengthening and rehabilitation of damaged full‐scale RC beams due to corrosions in the main reinforcement caused by BFRP sheets. Different parameters were taken into consideration such as corrosion grade, BFRP wrapping schemes, and the number of layers. The flexural performance of the models that build up as the control model and the damaged and the repaired methodologies by BFRP that are adopted and tested by others under the effects of four‐point static loadings were also underwent examination. The full interaction at BFRP‐concrete interface and the full bonding between sheets presupposed were investigated for all models. The numerical analysis findings were compared with the experimental measurements and found to be in good agreement. The current numerical analysis proved that the ultimate load rised by 14.8% in spite of 20% corrosion in the flexural steel rebar under eight layers of BFRP composite and bottom wrapping mode. In addition, under all strategies of wrapping schemes, the findings also indicated that the deflection ductility index noticeably reduced for RC beams with BFRP composites compared to the control beam. Finally, all the results of midspan deflection, crack patterns, and strain response of the composite system were analysed and discussed briefly.
A Predictive Model of Mining Collapse Extent and Its Application
Authors: Nan Jia , Liu Cheng , Liu Yi
Published: March 2019

To reveal the mechanical behavior mechanism of collapse and to control risks effectively, the instability extent of the collapse area was established through theoretical mechanics and numerical methods, taking one metal mine as a case study; on this basis, a routine reinforcement program was determined, and the effect of the program was evaluated. The results show the following. (1) Analytical formulas of the critical slip angle and the collapse height of the ore body were derived by the mechanics method, and the rock mechanics parameters were obtained by field coring and physical and mechanical experiments. The slipping line angle increases along with uniform force Q and is inversely proportional to the bending stiffness. Meanwhile, the calculation formula for the maximum subsidence of ore body was deduced. (2) Numerical results can be used to determine the basic form of the collapse area, and a “U‐shaped” collapse area formed when a plastic area passed completely through, resulting in the overall destruction. (3) The grouting reinforcement program includes “determining the instability region ⟶ roadway temporary support ⟶ improve the water environment and surrounding rock bearing capacity ⟶ mining planning” which were determined on the basis of prediction. (4) The hierarchical structure of the rock body and filling were improved combined with the Delphi method, and the grouting effect evaluation model was constructed and verified using the improved FD‐AHP method; the evaluation value indicating that the grouting reinforcement improved the bearing capacity of ore body and filling body in collapse area. The research results provide systematic reference and technical support for the analysis of stope collapse mechanism, prediction of hidden trouble, and the subsequent mining.
Roads and Intersections Extraction from High-Resolution Remote Sensing Imagery Based on Tensor Voting under Big Data Environment
Authors: Sun Ke , Zhang Junping , Zhang Yingying
Published: March 2019

Currently, big data is a new and hot object of research. In particular, the development of the Internet of things (IoT) results in a sharp increase in data. Enormous amounts of networking sensors are constantly collecting and transmitting data for storage and processing in the cloud including remote sensing data, environmental data, geographical data, etc. Road information extraction from remote sensing data is mainly researched in this paper. Roads are typical man-made objects. Extracting roads from remote sensing imagery has great significance in various applications such as GIS data updating, urban planning, navigation, and military. In this paper a multistage and multifeature method to extract roads and detect road intersections from high-resolution remotely sensed imagery based on tensor voting is presented. Firstly, the input remote sensing image is segmented into two groups including road candidate regions and nonroad regions using template matching; then we can obtain preliminary road map. Secondly, nonroad regions are removed by geometric characteristics of road (large area and long strip). Thirdly, tensor voting is used to overcome the broken roads and discontinuities caused by the different disturbing factors and then delete the nonroad areas that are mixed into the road areas due to mis-segmentation, improving the completeness of extracted roads. And then, all the road intersections are extracted by using tensor voting. The experiments are conducted on different remote sensing images to test the effectiveness of our method. The experimental results show that our method can get more complete and accurate extracted results than the state-of-the-art methods.
A Response Characteristics Study of Widespread Power Grid Icing to El Nino
Authors: Di Yuelun , Lu Jiazheng , Xu Xunjian , Feng Tao , Li Li
Published: March 2019

Under the circumstances of global climate change, the El Nino event affects power grid icing by influencing the winter climate characteristics. The response characteristics of the massive power grid icing to El Nino should be of concern. Based on analysis and comparison, this study found that the overall level of response of Hunan power grid icing to El Nino was weak in 2015 winter. Areas with severe power grid icing of Hunan at 2015 El Nino period are mainly distributed at the midwest and southeastern mountainous and surrounding areas, but the maximum ice thickness extremum area range is shrinking. The maximum ice thickness at the El Nino winter enhancing (weakening) follows the trend of El Nino increasing (decreasing). Overall, the maximum ice thickness response characteristics of Hunan power grid at the El Nino period can be divided into four types. This analysis of power grid icing characteristics during El Nino period summarizes the response characteristics of icing and can guide the research of power grid icing and ant‐icing countermeasures.
A Parabolic Failure Criterion for Transversely Isotropic Rock: Modification and Verification
Authors: Wang Ding-Jian , Tang Huiming , Shen Peiwu , Cai Yi
Published: March 2019

It is of great significance to develop a failure criterion that can describe the orientation‐dependent behavior of transversely isotropic rocks. This paper presents a simplified parabolic model that is successful in predicting the strengths of rocks under different confining pressures and bedding angles. The model is a modified version of the normal parabolic criterion for intact rocks. The two orientation‐dependent parameters (σcβ and kβ) in the model show trigonometric relationships with the bedding angle, and they can be readily determined through uniaxial and triaxial compression tests. The shape of the failure envelope is determined by kβ, and σcβ only affects the level of rock strength. With application to 446 experimental data, the predicting results by the parabolic criterion are highly consistent with the experimental data, and the predictive capacity of the proposed criterion is better than those of the McLamore‐Gray and Tien‐Kuo criteria. Besides, the prediction errors for the high confining pressure condition and the bedding‐sliding failure mode are smaller than those for the low confining pressure and the non‐bedding‐sliding failure. Moreover, the prediction error almost remains steady with the decrease of data set, indicating that the proposed criterion is of high precision even if the experimental data are limited.
Alternative Methods of Vaccine Delivery: An Overview of Edible and Intradermal Vaccines
Authors: Criscuolo E. , Caputo V. , Diotti R. A. , Sautto G. A. , Kirchenbaum G. A. , Clementi N.
Published: March 2019

Vaccines are recognized worldwide as one of the most important tools for combating infectious diseases. Despite the tremendous value conferred by currently available vaccines toward public health, the implementation of additional vaccine platforms is also of key importance. In fact, currently available vaccines possess shortcomings, such as inefficient triggering of a cell-mediated immune response and the lack of protective mucosal immunity. In this regard, recent work has been focused on vaccine delivery systems, as an alternative to injectable vaccines, to increase antigen stability and improve overall immunogenicity. In particular, novel strategies based on edible or intradermal vaccine formulations have been demonstrated to trigger both a systemic and mucosal immune response. These novel vaccination delivery systems offer several advantages over the injectable preparations including self-administration, reduced cost, stability, and elimination of a cold chain. In this review, the latest findings and accomplishments regarding edible and intradermal vaccines are described in the context of the system used for immunogen expression, their molecular features and capacity to induce a protective systemic and mucosal response.
Exploration of Mechanical Behaviors of Argillaceous Siltstone through Photoelastic Model Test and DEM Modelling
Authors: Li Weike , Han Jianqiang , Cui Jie , Luo Weili , Zheng Guangzao
Published: March 2019

This paper aims at investigating mechanical behaviors of argillaceous siltstone through a photoelastic model test and DEM modelling. Both bonded and unbonded conditions were considered. The photoelastic model was fabricated in a controllable environment, and its scaled factor was 1 : 200 in length and 11.9 : 1 in Young’s modulus. The polariscope was designed to have an area‐based LCD source and an automatic digital camera. A calibration test was carried out to obtain the relationship between the contact force and the average intensity gradient squared. A 2D DEM simulation is carried out for a 100 mm × 200 mm rectangular container filled with particles of 6 mm and 10 mm, in which the bonding effect is realized by adjusting the shear contact stiffness. The results show that both the photoelastic model and DEM modelling are able to capture the evolution of force chain network, effective contact number and stress concentration factor, and rheological behaviors when it is subjected to an increasing uniaxial load. The bonding effect plays an important role in the mechanical performance of argillaceous siltstone.
Impact of the Application of Domestic Wastewater by Subsurface Drip Irrigation on the Soil Solution in Sugarcane Cultivation
Authors: Nazário Aline Azevedo , Zution Gonçalves Ivo , Augusto Agnellos Barbosa Eduardo , Nazário Silva dos Santos Leonardo , Rodrigues Cavalcante Feitosa Daniel , Matsura Edson Eiji
Published: March 2019

The agricultural use of domestic sewage is a viable alternative for recycling nutrients; however, there is concern regarding the impact of its use due to the concentration of chemical elements present in this type of effluent. The use of principal component analysis determines the existence or lack of anomalous samples and the relations between measured variables and their relative contribution among samples that help in monitoring the impact of the use of effluents on soil chemical components. Thus, the objective of this work was to identify nutrient ions present in the soil solution during the first ratoon sugarcane irrigated with treated domestic sewage applied by subsurface drip irrigation. The experiment was conducted under a randomized block design with 5 treatments and 5 replicates. The treatments were distributed according to the type of water applied in the irrigation system (water surface reservoir and treated domestic sewage), the installation depth of the drip tapes (0.2 or 0.4 m depth), and the treatment without irrigation. By means of soil solution, it was possible to identify an increase in the concentration of salts in the treatments irrigated with treated domestic sewage, which however did not affect the soil quality in the short term. The principal component analysis selected the variables Ca2+, Mg2+, NO3−, K+, and EC as soil solution indicators to monitor areas irrigated with treated domestic sewage.
Design of Fixed Points in Boolean Networks Using Feedback Vertex Sets and Model Reduction
Authors: Kobayashi Koichi
Published: March 2019

Fixed points in Boolean networks (BNs) represent cell types or states of cells and are important to decide characteristics of cells. As the control problem on fixed points, it is important to consider the problem of changing fixed points by using external stimuli (i.e., control inputs). In this paper, we propose two methods for designing fixed points. First, a design method using model reduction is proposed. Using the reduced model, the problem of placing fixed points can be rewritten as an integer linear programming problem. Next, we consider the design problem using only the graph structure of a given BN and derive some results. In both methods, a feedback vertex set of a directed graph plays an important role. Finally, a biological example is presented.
Release Behavior of Folic Acid Grafted Hollow Hydroxyapatite as Drug Carrier
Authors: Liu Qing , Guo Wenjing , Yang Mei , Wang Kejie , Liu Weijun , Wu Fanhong
Published: March 2019

Based on the formation of carbodiimide compounds between carboxyl and primary amines, hollow microspheres arising from the folic acid (folate-FA) grafted onto the surface of the modified hydroxyapatite were successfully prepared. The hollow morphology and composition of the FA-grafted hydroxyapatite microspheres were confirmed by scanning electron microscopy (SEM) and other characterizations. Brunauer-Emmett-Teller (BET) assay revealed the specific surface area and average pore size of the microspheres were 34.58m2/g and 17.80 nm, respectively. As a drug carrier, the kinetic investigation of doxorubicin (DOX) loaded shows that the adsorbed behavior of drug on the adsorbent is more suitable to be described with pseudo-first-order model. Furthermore, the release rate can reach 83% at pH 5.7, which is greater than the release of 39% at pH 7.4, indicating an excellent performance of controlled drug release for response pH. The release mechanism of DOX coincides with Fickian diffusion as a result of Korsmeyer-Peppas model analysis and the release phenomena can be well explained by Fickian diffusion second law.
Epigenetic Regulation of the PTEN–AKT–RAC1 Axis by G9a Is Critical for Tumor Growth in Alveolar Rhabdomyosarcoma
Authors: Bhat Akshay V. , Palanichamy Kala Monica , Rao Vinay Kumar , Pignata Luca , Lim Huey Jin , Suriyamurthy Sudha , Chang Kenneth T. , Lee Victor K. , Guccione Ernesto , Taneja Reshma
Published: March 2019

Alveolar rhabdomyosarcoma (ARMS) is an aggressive pediatric cancer with poor prognosis. As transient and stable modifications to chromatin have emerged as critical mechanisms in oncogenic signaling, efforts to target epigenetic modifiers as a therapeutic strategy have accelerated in recent years. To identify chromatin modifiers that sustain tumor growth, we performed an epigenetic screen and found that inhibition of lysine methyltransferase G9a significantly affected the viability of ARMS cell lines. Targeting expression or activity of G9a reduced cellular proliferation and motility in vitro and tumor growth in vivo. Transcriptome and chromatin immunoprecipitation–sequencing analysis provided mechanistic evidence that the tumor-suppressor PTEN was a direct target gene of G9a. G9a repressed PTEN expression in a methyltransferase activity–dependent manner, resulting in increased AKT and RAC1 activity. Re-expression of constitutively active RAC1 in G9a-deficient tumor cells restored oncogenic phenotypes, demonstrating its critical functions downstream of G9a. Collectively, our study provides evidence for a G9a-dependent epigenetic program that regulates tumor growth and suggests targeting G9a as a therapeutic strategy in ARMS.

Significance:

These findings demonstrate that RAC1 is an effector of G9a oncogenic functions and highlight the potential of G9a inhibitors in the treatment of ARMS.
Recruiting for an Online Survey through Social Media: Testing Variations in Messaging, Compensation, and Platform
Authors: Selvan P , Kearney M , Massey PM , Leader AE
Published: March 2019

To test three recruitment strategies for parents on social media (Facebook and Twitter) to complete a brief survey about the human papillomavirus (HPV) vaccine. Methods: We created three campaigns with ads on Facebook and promoted tweets on Twitter that invited parents of children ages 9–15 to complete a brief survey about the HPV vaccine. Iterative, yet varied, campaigns were conducted to determine the ideal social media platform, compensation amount, and messaging. Ads depicted vaccine-eligible children (11–12 years of age) of various ethnicities. Ad messaging was adapted from social media toolkits at the CDC and the HPV Roundtable. Parents who clicked on our ad were first screened for eligibility. Those who were eligible then completed a 20-item survey via Qualtrics that included questions about HPV, the vaccine, and social media use. Survey compensation was either $5 or $10. At the end of the survey, we provided information about HPV and the vaccine. The campaign was available in English and Spanish. Results: The first campaign was launched on both Facebook and Twitter and offered $5 compensation. The Facebook component yielded 18,527 impressions; two adults were confirmed eligible by the screener and both completed the survey (100% screener to completion rate). Cost per survey was $349.45. The Twitter component received 143,661 impressions and yielded 18 completed surveys, with a screener to completion rate of 26% and a cost of $42.99 per survey. For the second campaign, we dropped Facebook and focused solely on Twitter, offering $10 compensation. We received 50,475 impressions that yielded 55 completed surveys (screener to completion rate = 71%) costing $4.78 each. The final campaign tested simpler messaging on Twitter with $10 compensation, and received 8,897 impressions, 38 survey completions (screener to completion rate = 88%), and cost $1.19 per survey. Conclusions: While Facebook is widely used among Americans, our findings may suggest that Twitter is more engaging and cost-effective. Recent Facebook policy changes may explain the differences seen in cost and survey completion. Understanding the reach and effectiveness of the different platforms will help ensure the success of an intervention using social media.
Are Skeletal Muscle Mass and Density Associated with Fatigue In Early-Stage Colorectal Cancer Patients?
Authors: Winkels RM , van Baar H , Beijer S , Kampman E
Published: March 2019

Both low skeletal muscle mass and low radiographic muscle density are associated with higher complication rates after surgery for colorectal cancer and with worse survival rates although data are not fully consistent. Whether skeletal muscle mass and density are also associated with patient-reported outcomes, such as fatigue, is less well studied. We hypothesized that low skeletal muscle mass and density may be associated with fatigue in early stage colorectal cancer (CRC) patients. Methods: Within a prospective cohort of 594 early-stage (stage I-III) CRC patients, we collected information on fatigue using the EORTC QLQ-C30 questionnaire 6 months after diagnosis; fatigue was defined as a score of >39 based on literature. Skeletal muscle mass and -density were assessed using pre-operative Computed Tomography (CT) images. Low muscle mass and -density were identified using previously determined cut- off values. Cox regression models were used to calculate prevalence ratios (PRs). All PRs were adjusted for age, sex, stage of disease. Results: The average age of the study population was 65.7 ± 9.0; 37% were women and 67% of the patients had a tumor located in the colon. Low muscle mass was present in 26% of the patients and low muscle density in 25%; 26% of patients had fatigue. Low muscle mass was not associated with prevalence of fatigue (PR for low versus normal muscle mass 0.83 (95%CI 0.56–1.24). Low muscle density was associated with higher prevalence of fatigue: PR for low versus normal muscle density 1.94 (95% CI 1.34–2.81). Conclusion: Among colorectal cancer patients, low skeletal muscle density at diagnosis - indicative for fat infiltration in the muscle- was associated with a higher prevalence of fatigue six months after diagnosis. Future studies should assess how lifestyle interventions can help to prevent or decrease fatigue, and should further clarify whether there is a causal link between fat infiltration in the muscle and fatigue.
Neddylation Inactivation Facilitates FOXO3a Nuclear Export to Suppress Estrogen Receptor Transcription and Improve Fulvestrant Sensitivity
Authors: Jia Xiaoqing , Li Chunjie , Li Lihui , Liu Xiaoli , Zhou Lisha , Zhang Wenjuan , Ni Shuaishuai , Lu Yun , Chen Li , Jeong Lak Shin , Yu Jinha , Zhang Yingjian , Zhang Jianping , He Simin , Hu Xin , Sun Hefen , Yu Keda , Liu Guangyu , Zhao Hu , Zhang Yanmei , Jia Lijun , Shao Zhi-Ming
Published: March 2019

Purpose:

How the neddylation pathway functions in breast tumor and regulation of estrogen receptor (ER) expression is rarely reported. The purpose of this study was to identify the role of neddylation in breast cancer and ER expression, and further explore the underlying mechanisms.

Experimental Design:

Expression patterns of nedd8-activating enzyme (NAE) and nedd8, two key proteins in the neddylation pathway, were examined in human breast specimens. ER-α expression was investigated using animal 18F-FES-PET/CT and immunoblotting upon NAE inhibitor MLN4924 treatment. Chromatin immunoprecipitation assay, luciferase reporter promoter assay, and the CRISPR-Cas9 system were used to elucidate the mechanism of ER-α regulation by MLN4924. The ER-positive breast cancer mouse model was used to determine the synergetic effect of MLN4924 and fulvestrant on tumor growth. All statistical tests were two-sided.

Results:

Both NAE1 and nedd8 expressions were higher in the ER-positive subgroup. Higher expressions of NAE1 and nedd8 indicated poorer prognosis. Importantly, ER-α expression was significantly downregulated upon MLN4924 treatment in vitro and in vivo. Mechanistically, MLN4924 treatment delayed serum and glucocorticoid-induced protein kinase (SGK) degradation and induced Forkhead box O3a (FOXO3a) nuclear export as well as decreased binding to the ESR1 promoter. Importantly, MLN4924 single or synergized with fulvestrant significantly suppressed the growth of ER-positive breast cancer in vitro and in vivo.

Conclusions:

Our proof-of-principle study determines the activation of neddylation in breast tumor tissues for the first time and reveals a new ER-α regulatory mechanism, as well as further explores an effective approach to improve fulvestrant sensitivity through a neddylation inactivation combination.
The Immune Subtypes and Landscape of Squamous Cell Carcinoma
Authors: Li Bailiang , Cui Yi , Nambiar Dhanya K. , Sunwoo John B. , Li Ruijiang
Published: March 2019

Purpose:

To identify immune subtypes and investigate the immune landscape of squamous cell carcinomas (SCC), which share common etiology and histologic features.

Experimental Design:

Based on the immune gene expression profiles of 1,368 patients with SCC in the Cancer Genome Atlas (TCGA), we used consensus clustering to identify robust clusters of patients and assessed their reproducibility in an independent pan-SCC cohort of 938 patients. We further applied graph structure learning-based dimensionality reduction to the immune profiles to visualize the distribution of individual patients.

Results:

We identified and independently validated six reproducible immune subtypes associated with distinct molecular characteristics and clinical outcomes. An immune-cold subtype had the least amount of lymphocyte infiltration and a high level of aneuploidy, and these patients had the worst prognosis. By contrast, an immune-hot subtype demonstrated the highest infiltration of CD8+ T cells, activated NK cells, and elevated IFNγ response. Accordingly, these patients had the best prognosis. A third subtype was dominated by M2-polarized macrophages with potent immune-suppressive factors such as TGFβ signaling and reactive stroma, and these patients had relatively inferior prognosis. Other subtypes showed more diverse immunologic features with intermediate prognoses. Finally, our analysis revealed a complex immune landscape consisting of both discrete clusters and continuous spectrum.

Conclusions:

This study provides a conceptual framework to understand the tumor immune microenvironment of SCCs. Future work is needed to evaluate its relevance in the design of combination treatment strategies and guiding optimal selection of patients for immunotherapy.