bluuebunny/crossref_metadata_2025 huggingface dataset:
On an alternative, implicit renormalization procedure for the Casimir energy
Authors: Dubikovsky A. I. , Silaev P. K.
Published: July 2018

We propose a procedure for the renormalization of Casimir energy that is based on the implicit versions of standard steps of renormalization procedure — regularization, subtraction and removing the regularization. The proposed procedure is based on the calculation of a set of convergent sums, which are related to the original divergent sum for the non-renormalized Casimir energy. Then, we construct a linear equation system that connects this set of convergent sums with the renormalized Casimir energy, which is a solution to this system of equations. This procedure slightly reduces the indeterminacy that arises in the standard procedure when we choose the particular regularization and the explicit form of the counterterm. The proposed procedure can be applied not only to systems with the explicit transcendental equation for the spectrum but also to systems with the spectrum that can be obtained only numerically. However, to perform the proposed procedure, we need a parameter of the system that satisfies two conditions: (i) we can obtain explicit analytical expressions (as a function of our parameter) for coefficients for all divergent and unphysical terms in divergent sum for Casimir energy; (ii) infinite value of this parameter should be the “natural” renormalization point, i.e. Casimir energy must tend to zero when parameter tends to infinity.
Transmittance properties of a quasi-periodic one-dimensional photonic crystals that incorporate nanocomposite material
Authors: Aly Arafa H. , Malek Christina , Elsayed Hussein A.
Published: July 2018

In this paper, we investigate theoretically the transmission properties of one-dimensional quasi-periodic photonic crystals that containing nanocomposite material in the IR wavelength regions. Our structure is particularly designed using the Fibonacci role. Here, the nanocomposite material is composed of nanoparticles of Ag that are randomly immersed in a host dielectric material of SiO2. Numerical results are mainly investigated based on the well-known characteristic matrix method. The numerical results show the appearance of many photonic bandgaps due to the multiple periodicities of our structure. Furthermore, the effects of the parameters of the nanocomposite such as the volume fraction, the refractive index of the dielectric material and the size of the nanoparticles have distinct effects on the transmittance characteristics of our structure. Wherefore, the proposed structure could be considered the cornerstone for many applications such as multichannel filters and optical switches.
Stochastic resonance in a time-delayed tumor cell growth system driven by additive and multiplicative noises
Authors: Zhang Gang , Shi Jiabei , Zhang Tianqi
Published: July 2018

In this paper, the stochastic resonance (SR) phenomenon in a time-delayed tumor cell growth system subjected to a multiplicative periodic signal, the multiplicative and additive noise is investigated. By applying the small time-delay method and two-state theory, the expressions of the mean first-passage time (MFPT) and signal-to-noise ratio (SNR) are obtained, then, the impacts of time delay, noise intensities and system parameters on the MFPT and SNR are discussed. Simulation results show that the multiplicative and additive noise always weaken the SR effect; while time delay plays a key role in motivating the SR phenomenon when noise intensities take a small value, it will restrain SR phenomenon when noise intensities take a large value; the cycle radiation amplitude always plays a positive role in stimulating the SR phenomenon, while, system parameters play different roles in motivating or suppressing SR under the different conditions of noise intensities.
The Impact of Macroeconomic Factors on Environmental Loss Ratio: Evidence from Taiwanese Insurance Data
Authors: Lai Li-Hua , Chen Ching-Hao , Chang Tung-Cheng
Published: July 2018

Environmental insurance (EI) protections help resolve the firm-industry economic loss problem. However, the loss ratio of EI is positively affected by itself from one period ahead. The positive and negative effects of macroeconomic factor on the loss ratio of EIs are not necessarily consistent, but they are dependent on the effect of the year’s environmental condition. The economic variables affecting the loss ratio of EI are quite inconsistent, so insurance prices and liability reserves should be modified every year. While the investigations are the special properties of our input data of Taiwan, the prescription of this paper could provide cross-references with other countries.
TAKING OR AVOIDING RISK THROUGH SECRET INNOVATION ACTIVITIES — THE RELATIONSHIPS AMONG EMPLOYEES’ RISK PROPENSITY, BOOTLEGGING, AND MANAGEMENT SUPPORT
Authors: GLOBOCNIK DIETFRIED
Published: July 2018

This study aims to contribute to the research on bootlegging by investigating (i) whether employees’ risk propensity explains why some secretly organise innovation, whereas others do not, and (ii) how direct management support for compliant innovative behaviour affects this relationship. Answers to these questions are relevant because managers experience bootlegging in their organisations but do neither know from which employees they can expect creative deviance nor how to regulate it. Drawing on risk behaviour theory, risk propensity is supposed to foster bootlegging behaviour, and different forms of management support moderate this relationship by changing the salience of opportunities and the threats inherent in “going underground”. The empirical results provide ample support for the direct impact of risk propensity. This effect becomes weaker when managers provide more support in the form of resources and feedback, whereas encouragement to innovate strengthens the relationship.
Superfast Preparation of SWNT Sponge by Flame Burning Method and Its Adsorptive, Elastic and Electrochemical Properties
Authors: Lu Liang , Tong Hao , Jin Fengqiao , Yue Shihong , Meng Qing , Zhang Xiaogang
Published: July 2018

A compressible single-walled carbon nanotube (SWNT) sponge was developed by a superfast flame burning method in less than 20[Formula: see text]s by moving polyurethane (PU) sponge template coated with SWNTs through an ethanol flame. By adjusting the geometries of the templates, the arbitrary shapes of the SWNT sponges composed of a unique network structure could be prepared as required. The SWNT sponges possessing good hydrophobicity and outstanding organic solvent adsorption capacity could adsorb various organic solvents and oils with high adsorption rate and good adsorption–volatilization and adsorption–combustion recycling performance. The SWNT sponges present good elasticity and compression stability even after a compressive strain of 80% and the 1000th loading/unloading cycle due to the stable skeleton structures. The SWNT sponges as flexible electrodes could also achieve high-specific capacitance of 126.8[Formula: see text]F[Formula: see text]g[Formula: see text] at 1[Formula: see text]A[Formula: see text]g[Formula: see text] and 95% capacitance retention after 10 000 charge/discharge cycles. Owing to the availability of the flame, easy decomposition of the PU sponge and flame resistance of SWNTs, this facile flame burning method was demonstrated to be a practical approach to prepare the SWNT sponges on a large scale with controllable shape and density, moderate organic liquid adsorption capability, good elasticity and decent electromechanical properties.
Analysis and Design of an Effective Light Interference Methane Sensor Based on Three-Dimensional Optical Path Model
Authors: Long Teng , Li En , Yang Lei , Fan Junfeng , Liang Zize
Published: July 2018

As an important environmental monitoring equipment, the existing methane sensors or the traditional interferometer-based methane detectors have some drawbacks, such as low accuracy, large size, and complex calibration operations. Moreover, the optical path model and analysis method for the light interference methane sensor are not practical. In this paper, an effective light interference methane sensor is proposed based on a three-dimensional optical path model with point light source. Based on this model, the interference optical system is studied to illustrate the cause of the interference fringes. Furthermore, the influencing factors of the light intensity distribution are analyzed and an adjustment method for the interference fringes is proposed, which helps to simplify the assembling and calibrating operations. In order to improve the measurement accuracy, a temperature drift compensation method which includes a mapping table, a steady-state compensator, and a dynamic compensator is proposed. The mapping table is established between the output voltages of photoelectric detector, and the methane concentration, the steady-state compensator, and the dynamic compensator are proposed to eliminate the temperature drift. Finally, an experimental device for the light interference methane sensor is constructed to validate the interference fringe adjustment method and the temperature drift compensation method.
Modified PCI Multipliers for Time‐Dependent Deformation of PSC Bridges
Authors: Lee Joo-Ha , Lim Kwang-Mo , Park Chan-Gi
Published: July 2018

Nowadays prestressed concrete (PSC) bridges have become very common, but there are still many difficulties in predicting their long‐term behavior. In order to predict the long‐term behavior of PSC bridges, it is possible to use very complex formulas developed by various researchers or numerical analysis through computer, but many engineers are having difficulty in using such methods. Moreover, the accuracy of the prediction result is not satisfactory compared to the effort. On the contrary, the PCI Bridge Design Manual proposes a method that can easily predict the long‐term behavior using multipliers. However, this method does not take into account various construction schedules and has some assumptions that are inadequate for the current situation in various girder sections and topping thicknesses. Therefore, in this study, new long‐time factors were developed by modifying the multipliers of the PCI Bridge Design Manual by a rational manner. This allows prediction of long‐term behavior of bridges taking into account various construction schedules and the characteristics of modern girder sections. The prediction results of the long‐term camber and deflection of PSC bridges using the proposed multipliers were compared with those using the basic PCI Bridge Design Manual, the improved PCI Bridge Design Manual, KR C‐08090 (same as ACI 318‐14), and numerical analysis. As a result, the newly proposed method makes possible to predict the long‐term behavior at any time after casting, and the accuracy of the prediction is also improved.
The Effect of NSAID Pretreatment on Aqueous Humor Prostaglandin E2 Concentration in Eyes Undergoing Femtosecond Laser-Assisted Capsulotomy
Authors: Diakonis Vasilios F. , Anagnostopoulos Apostolos G. , Moutsiopoulou Angeliki , Yesilirmak Nilufer , Cabot Florence , Waren Daniel P. , O’Brien Terrence P. , Yoo Sonia H. , Weinstock Robert J. , Donaldson Kendall E.
Published: July 2018

Purpose. To assess aqueous humor concentration of prostaglandin E2 (PGE2) after capsulotomy creation using a femtosecond laser (FLAC) in patients pretreated with short-term topical ketorolac versus patients without pretreatment. Methods. This prospective study comprised consecutive patients scheduled to undergo cataract surgery using a femtosecond laser platform to perform only capsulotomies. An identical protocol for preoperative mydriasis was used for all the eyes included in the study, while aqueous humor was extracted from the anterior chamber of all patients immediately after the initial side port incision. ELISA was performed to quantify aqueous humor PGE2. The patients were divided into 2 groups; in group 1, the patients received short-term topical ketorolac preoperatively, while the patients in group 2 did not receive NSAID pretreatment. Results. Twenty eyes of 20 patients were included in the study (10 eyes in each group). Mean concentration of aqueous humor PGE2 after FLAC was 392.16 ± 162.00 pg/ml and 622.63 ± 331.84 pg/ml for groups 1 and 2, respectively. A statistically significant difference in aqueous humor PGE2 concentration between the two groups (p<0.05) was demonstrated, with the eyes that received ketorolac pretreatment demonstrating a lower concentration of PGE2. Conclusion. Short-term topical use of ketorolac prior to FLAC seems to prevent excessive release of PGE2 in the anterior chamber of the eyes that received NSAID pretreatment when compared to the eyes that did not receive NSAIDs preoperatively.
New Chemical Grouting Materials and Rapid Construction Technology for Inclined Shaft Penetrating Drift‐Sand Layer in Coal Mine
Authors: Gao Xicai , Wang Xinyu , Liu Xiangdong
Published: July 2018

Drift‐sand layer is a common weak stratum in mine construction. The construction of the shaft passing over the drift‐sand layer is very difficult. Traditional construction method faces many problems such as long construction period, high construction cost, poor working environment, and uncontrollability of the support effect. In view of the loose and fragile rock mass with great deformation of sinking and driving engineering penetrating drift‐sand layers in coal mine, the reaction mechanism and shortcomings of conventional chemical grouting materials were analyzed. New‐type polymer grouting materials were prepared with catalysts and vinyl epoxy resin, which was made from epoxy resin. A comprehensive chemical grouting construction technology was proposed, which comprises initiative closing, concentrated bypass flow, water plugging priority, and secondary sand curing for the inclined shaft passing over the drift‐sand layer. Results show that new‐type polymer sand‐cured materials have lower viscosity, better grout ability, and fire resistance, and the solidified material has stronger bonding strength and better deformation resistance compared with traditional chemical grouting materials. The engineering application effect is very prominent in controlling water burst and leakage at the drift‐sand layer; thus the on‐site comprehensive construction progress and safety are guaranteed.
A SHPB Experimental Study on Dynamic Mechanical Property of High‐Damping Rubber
Authors: Li Xiudi , Mao Huaiyuan , Xu Ke , Miao Chaoyang
Published: July 2018

A split Hopkinson pressure bar (SHPB) experiment was done to examine the feasibility and explosion resistance of high‐damping rubber materials developed for use in the area of antiexplosion applications. Through the experiment, the dynamic mechanical properties of the high‐damping rubber were determined. The existence of dynamic compressive stress‐strain curves at various strain rates of the high‐damping rubber have been confirmed from the SHPB experiment. The variation law of the dynamic compression performance with the strain rate is studied, and the energy absorption characteristics of high‐damping rubber materials are analyzed. To study the microstructural changes of the high‐damping rubber before and after impact, a scanning electron microscopy (SEM) test was done. The results indicated that the stress‐strain curve and dynamic modulus of high‐damping rubber has an obvious strain rate effect, and the strength and energy absorption ability of high‐damping rubber material increases with an increase in the strain rate; the ideal energy absorption efficiency of high‐damping rubber can reach 0.8 at a high strain rate and the ideal energy absorption efficiency is more than 0.5 in a wide deformation range; when compared with aluminum foam, the energy absorption effect for high‐damping rubber is more apparent. In the event of a compressed deformation or the creation of holes, there may be a change in the main internal mechanism of the high buffering and energy absorption capacity of the high‐damping rubber.
Modelling and Assertion-Based Verification of Run-Time Reconfigurable Designs Using Functional Programming Abstractions
Authors: Uchevler Bahram N. , Svarstad Kjetil
Published: July 2018

With the increasing design and production costs and long time-to-market for Application Specific Integrated Circuits (ASICs), implementing digital circuits on reconfigurable hardware is becoming a more common practice. A reconfigurable hardware combines the flexibility of the software domain with the high performance of the hardware domain and provides a flexible life cycle management for the product with a lower cost. A complete design and assertion-based verification flow for Run-Time Reconfigurable (RTR) designs using functional programming abstractions of Haskell are proposed in this article, in which partially reconfigurable hardware is used as the implementation platform. The proposed flow includes modelling of RTR designs in high levels of abstraction by using higher-order functions and polymorphism in Haskell, as well as their implementation on partially reconfigurable Field Programmable Gate Arrays (FPGAs). Assertion-based verification (ABV) is used as the verification approach which is integrated in the early stages of the design flow. Assertions can be used to verify specifications of designs in different verification methods such as simulation-based and formal verification. A partitioning algorithm is proposed for clustering the assertion-checker circuits to implement the verification circuits in a limited reconfigurable area in the target FPGA. The proposed flow is evaluated by using example designs on a Zynq FPGA as the hardware/software implementation platform.
DOA Estimation for a Mixture of Uncorrelated and Coherent Sources Based on Hierarchical Sparse Bayesian Inference with a Gauss-Exp-Chi2 Prior
Authors: Zhao Pinjiao , Si Weijian , Hu Guobing , Wang Liwei
Published: July 2018

Direction of arrival (DOA) estimation algorithms based on sparse Bayesian inference (SBI) can effectively estimate coherent sources without recurring to extra decorrelation techniques, and their estimation performance is highly dependent on the selection of sparse prior. Specifically, the specified sparse prior is expected to concentrate its mass on the zero and distribute with heavy tails; otherwise, these algorithms may suffer from performance degradation. In this paper, we introduce a new sparse-encouraging prior, referred to as “Gauss-Exp-Chi2” prior, and develop an efficient DOA estimation algorithm for a mixture of uncorrelated and coherent sources under a hierarchical SBI framework. The Gauss-Exp-Chi2 prior distribution exhibits a sharp peak at the origin and heavy tails, and this property makes it an appropriate prior to encourage sparse solutions. A three-layer hierarchical sparse Bayesian model is established. Then, by exploiting variational Bayesian approximation, the model parameters are estimated by alternately updating until Kullback-Leibler (KL) divergence between the true posterior and the variational approximation becomes zero. By constructing the source power spectra with the estimated model parameters, the number and locations of the highest peaks are extracted to obtain source number and DOA estimates. In addition, some implementation details for algorithm optimization are discussed and the Cramér-Rao bound (CRB) of DOA estimation is derived. Simulation results demonstrate the effectiveness and favorable performance of the proposed algorithm as compared with the state-of-the-art sparse Bayesian algorithms.
Deformation Forecasting of Surrounding Rock Mass Based on Correlation between Frequency and Fracture Scale of Microseismicity
Authors: Xiao Peiwei , Qian Bo , Jiang Peng , Xu Nuwen , Li Biao
Published: July 2018

The macroscopic deformation and failure of engineering rock mass may occur as a result of evolution and breakdown of its internal microfracture. Therefore, the macroscopic state of rock mass can be obtained from fracture scale of microfracture in real time. To assess instability and predict macroscopic deformation and failure of engineering rock mass, a time‐frequency analysis technique based on S transform was proposed to investigate microseismic waveform and reveal the correlation between macroscopic deformation failure and microseismic frequency characteristics of engineering rock mass in combination with fracture scale. To minimize the influence of external factors on parameters calculated, a significant amount of microseismic data from three large‐scale hydropower projects in southwestern China was collected as the statistical sample. The analysis of correlation between fracture scale and frequency characteristics of microseismic events was carried out based on the statistical sample. Combining with microseismic data and multipoint extensometers in the underground powerhouse of the Houziyan hydropower station, engineering verification was conducted. The result shows that the high‐frequency components decrease and microseismic signals display low‐frequency characteristic as the fracture scale increases; the microseismic high‐frequency components decreased at first and then increased during the deformation process of surrounding rock mass, and the frequency of microseismic events shifts from high band to a lower one before deformation.
Polyarylene Ether Nitrile-Based High-k Composites for Dielectric Applications
Authors: You Yong , Zhan Chenhao , Tu Ling , Wang Yajie , Hu Weibin , Wei Renbo , Liu Xiaobo
Published: July 2018

Flexible polymer-based composites exhibiting high dielectric constant as well as low dielectric loss have been intensively investigated for their potential utilization in electronics and electricity industry and energy storage. Resulting from the polar -CN on the side chain, polyarylene ether nitrile (PEN) shows relatively high dielectric constant which has been extensively investigated as one of the hot spots as dielectric materials. However, the dielectric constant of PEN is still much lower than the ceramic dielectrics such as BaTiO3, TiO2, and Al2O3. In this review, recent and in-progress advancements in the designing and preparing strategies to obtain high-k PEN-based nanocomposites are summarized. According to the types of the added fillers, the effects of organic fillers, dielectric ceramic fillers, and conductive fillers on electric properties of PEN-based composites are investigated. In addition, other factors including the structures and sizes of the additive, the compatibility between the additive agent and the PEN, and the interface which affects the dielectric properties of the obtained composite materials are investigated. Finally, challenges facing in the design of more effective strategies for the high-k PEN-based dielectric materials are discussed.
A Simplified Nonlinear Method for a Laterally Loaded Pile in Sloping Ground
Authors: Yin Pingbao , He Wei , Yang Zhaohui Joey
Published: July 2018

A simplified nonlinear method was proposed to evaluate lateral behavior of a pile located in or nearby a slope, based on the traditional p‐y method. This method was validated with field test results of a steel pipe pile in clay and model tests of piles in sand slopes. The comparison indicated that the calculated horizontal displacement and bending moment of piles agree well with experimental results. Then, parametric studies were performed, and it shows that horizontal displacement, rotation, bending moment, and shear force increase along with increasing slope angles; the depth of maximum moment locates at about 1.6 D below ground surface for horizontal ground, while this value turns to be about 3.6 D and 5.6 D for sloping ground of 30° and 60°, respectively. The study clearly shows that slope angle has a significant effect on the deflection and lateral capacity of piles.
Temporal Trends and Spatial Patterns of Temperature and Its Extremes over the Beijing-Tianjin Sand Source Region (1960–2014), China
Authors: Wei Wei , Wang Baitian , Zhang Kebin , Shi Zhongjie , Ge Genbatu , Yang Xiaohui
Published: July 2018

In order to examine temperature changes and extremes in the Beijing-Tianjin Sand Source Region (BTSSR), ten extreme temperature indices were selected, categorized, and calculated spanning the period 1960–2014, and the spatiotemporal variability and trends of temperature and extremes on multitimescales in the BTSSR were investigated using the Mann-Kendall (M-K) test, Sen’s slope estimator, and linear regression. Results show that mean temperatures have increased and extreme temperature events have become more frequent. Annual temperature has recorded a significant increasing trend over the BTSSR, in which 51 stations exhibited significant increasing trends (p<0.05); winter temperature recorded the most significant increasing trend in the northwest subregion. All extreme temperature indices showed warming trends at most stations; a higher warming slope in extreme temperature mainly occurred along the northeast border and northwest border and in the central-southern mountain area. As extreme low temperature events decrease, vegetation damage due to freezing temperatures will reduce and low cold-tolerant plants may expand their distribution range northward to revegetate barren areas in the BTSSR. However, in water-limited areas of the BTSSR, increasing temperatures in the growing season may exacerbate stress associated with plants relying on precipitation due to higher temperatures combining with decreasing precipitation.
Incidence and Health Related Quality of Life of Opioid-Induced Constipation in Chronic Noncancer Pain Patients: A Prospective Multicentre Cohort Study
Authors: Veiga Dalila R. , Mendonça Liliane , Sampaio Rute , Lopes José C. , Azevedo Luís F.
Published: July 2018

Background. High rates of opioid use for chronic noncancer pain (CNCP) have been reported worldwide, despite its association with adverse events, inappropriate use, and limited analgesic effect. Opioid-induced constipation (OIC) is the most prevalent and disabling adverse effect associated with opioid therapy. Our aim was to assess the incidence, health related quality of life (HRQOL), and disability in OIC patients. Methods. A prospective cohort study was performed, with 6 months of follow-up, of adult CNCP patients consecutively admitted in 4 multidisciplinary pain clinics (MPC). Demographic and clinical data have been collected. Brief Pain Inventory (BPI) and Short version of Treatment Outcomes in Pain Survey (S-TOPS) were used to measure functional outcomes and HRQOL. OIC was assessed using Bowel Function Index (BFI). Results. 694 patients were recruited. OIC prevalence at baseline was 25.8%. At 6 months, OIC incidence was 24.8%. Female gender (OR = 1.65, p=0.039), opioid therapy (OR 1.65, p=0.026), and interference pain score on BPI (OR 1.10, p=0.009) were identified as OIC independent predictors. OIC patients presented higher disability and pain interference and severity scores. OIC patients reported less satisfaction with outcome (p=0.038). Discussion. Constipation is a common adverse event among opioid users with major functional and quality of life impairment. These findings emphasise the need of OIC adequate assessment and management.
The Factors Affecting Survival in Geriatric Hemodialysis Patients
Authors: Tuğcu Murat , Kasapoğlu Umut , Şahin Gülizar , Apaydın Süheyla
Published: July 2018

Introduction. The number of geriatric patients is increasing in hemodialysis population over the years and mortality is higher in this group of patients. This study evaluated the factors affecting geriatric hemodialysis patient survival. Materials and Methods. This retrospective cohort study enrolled patients discharged from our nephrology clinic from 2009 to 2014. Data collected included demographics, Eastern Cooperative Oncology Group-Performance Status, vascular access type, and metabolic parameters. Comorbidity was quantified using the modified Liu comorbidity index. The outcome measure was mortality. Results. The study enrolled 99 elderly dialysis patients (42.4% women (n = 42); mean age 75 ± 7 years). The mean follow-up duration was 19.7 ± 11 months. The mortality rate over the four years was 47.5% (n = 46). The modified Liu comorbidity index score, patient age, and Eastern Cooperative Oncology Group-Performance Status were significantly related to mortality in univariate and multivariate analyses. Conclusion. The present study revealed that comorbidities and low performance status at the onset of dialysis had shortened the survival time in the geriatric hemodialysis patient group.
Alteration in the Cytokine Secretion of Bone Marrow Stromal Cells from Patients with Chronic Myelomonocytic Leukemia Contribute to Impaired Hematopoietic Supportive Activity
Authors: Shi Hui , Wang Yingshao , Li Rong , Xing Wen , Yang Feng-Chun , Bai Jie , Zhou Yuan
Published: July 2018

Bone marrow stromal cells (BMSCs) represent an important cellular component of the bone marrow microenvironment, which play an important role in supporting and regulating the proliferation and differentiation of hematopoietic stem/progenitor cells (HSPCs). We have previously reported that the ability of BMSCs derived from CMML patients (CMML-BMSCs) in supporting the expansion of cord blood (CB) CD34+cells was significantly reduced compared to BMSCs derived from healthy donors (HD-BMSCs). In addition, CMML-BMSCs led to a skewed differentiation of CB CD34+cells favoring myeloid lineage compared with HD-BMSCs. To assess whether the altered cytokine secretion was one of the mechanisms to mediate the impaired hematopoietic supportive activity of CMML-BMSCs, a transwell coculture followed by cytokine array was performed. We showed that noncontacted coculture with CMML-BMSCs preferentially promoted the differentiation of CB CD34+cells toward myeloid lineage. The expression levels of multiple cytokines (IL-6, IL-8, and GRO-β) were markedly reduced in CMML-BMSCs compared with HD-BMSCs. By supplementing IL-6, IL-8, or GRO-β, the hematopoietic supportive activity of CMML-BMSCs was partially restored. These results suggested that BMSCs may contribute to the pathogenesis of CMML by altering their cytokine secretion, which will shed light on the further investigation to develop novel therapeutic strategies for CMML patients.
A Spectrum Sensing Method Based on Empirical Mode Decomposition and K‐Means Clustering Algorithm
Authors: Wang Yonghua , Zhang Yongwei , Wan Pin , Zhang Shunchao , Yang Jian
Published: July 2018

To solve the problems of poor performance of traditional spectrum sensing method under low signal‐to‐noise ratio, a new spectrum sensing method based on Empirical Mode Decomposition algorithm and K‐means clustering algorithm is proposed. Firstly, the Empirical Mode Decomposition algorithm and the wavelet threshold algorithm are used to remove the noise components in the spectrum sensing signal, and K‐means clustering algorithm is used to determine whether the primary user exists. The method can remove the redundant components such as noise in the nonstationary or nonlinear sampling signal in the real environment and does not need to know the prior information such as signal, channel, and noise, so it can well handle the complicated sensing signal in real environment. This method can reduce the impact of noise on the spectrum sensing system and thus can improve the sensing performance of the system. In the experimental part, the difference between maximum and minimum eigenvalues and the difference between the maximum eigenvalue and the average energy in the random matrix are selected as signal features. Experiments also show that the proposed method is better than the traditional spectrum sensing methods.
Quantitative Determination of Chlormequat Chloride Residue in Wheat Using Surface-Enhanced Raman Spectroscopy
Authors: Weng Shizhuang , Qiu Mengqing , Dong Ronglu , Wang Fang , Zhao Jinling , Huang Linsheng , Zhang Dongyan
Published: July 2018

A simple and sensitive method for detection of chlormequat chloride residue in wheat was developed using surface-enhanced Raman spectroscopy (SERS) coupled with chemometric methods on a portable Raman spectrometer. Pretreatment of wheat samples was performed using a two-step extraction procedure. Effective and uniform active substrate (gold nanorods) was prepared and mixed with the sample extraction solution for SERS measurement. The limit of detection for chlormequat chloride in wheat extracting solutions and wheat samples was 0.25 mg/L and 0.25 μg/g, which was far below the maximum residual value in wheat of China. Then, support vector regression (SVR) and kernel principal component analysis (KPCA), multiple linear regression, and partial least squares regression were employed to develop the regression models for quantitative analysis of chlormequat chloride residue with spectra around the characteristic peaks at 666, 713, and 853 cm−1. As for the residue in wheat, the predicted recovery of established optimal model was in the range of 94.7% to 104.6%, and the standard deviation was about 0.007 mg/L to 0.066 mg/L. The results demonstrated that SERS, SVR, and KPCA can provide the accurate and quantitative determination for chlormequat chloride residue in wheat.
Role of White Blood Cells in Blood- and Bone Marrow-Based Autologous Therapies
Authors: King William , Toler Krista , Woodell-May Jennifer
Published: July 2018

There has been significant debate over the role of white blood cells (WBCs) in autologous therapies, with several groups suggesting that WBCs are purely inflammatory. Misconceptions in the practice of biologic orthopedics result in the simplified principle that platelets deliver growth factors, WBCs cause inflammation, and the singular value of bone marrow is the stem cells. The aim of this review is to address these common misconceptions which will enable better development of future orthopedic medical devices. WBC behavior is adaptive in nature and, depending on their environment, WBCs can hinder or induce healing. Successful tissue repair occurs when platelets arrive at a wound site, degranulate, and release growth factors and cytokines which, in turn, recruit WBCs to the damaged tissue. Therefore, a key role of even pure platelet-rich plasma is to recruit WBCs to a wound. Bone marrow contains a complex mixture of vascular cells, white blood cells present at much greater concentrations than in blood, and a small number of progenitor cells and stem cells. The negative results observed for WBC-containing autologous therapies in vitro have not translated to human clinical studies. With an enhanced understanding of the complex WBC biology, the next generation of biologics will be more specific, likely resulting in improved effectiveness.
Daytime Sleepiness in Patients Diagnosed with Sarcoidosis Compared with the General Population
Authors: Hinz Andreas , Geue Kristina , Zenger Markus , Wirtz Hubert , Bosse-Henck Andrea
Published: July 2018

Background. The aim of this study was to analyze daytime sleepiness in a sample of patients diagnosed with sarcoidosis. Methods. A sample of 1197 German sarcoidosis patients was examined with the Epworth Sleepiness Scale (ESS), the Fatigue Assessment Scale, the Hospital Anxiety and Depression Scale, the Pittsburgh Sleep Quality Index, and the Short-Form Health Survey (SF-8). The patients’ ESS mean scores were compared with those obtained from a large general population sample. Results. Exactly 50% of the patients reached the criterion (ESS > 10) for excessive daytime sleepiness, compared with only 22.1% in the general population. The effect size for the mean score difference between both samples was d=0.62. The number of affected organs and the number of concomitant diseases proved to be significant independent predictors of daytime sleepiness. Sleepiness was associated with fatigue (r=0.45), anxiety (r=0.23), depression (r=0.28), sleep problems (r=0.23), and detriments in physical (r=−0.29) and mental (r=−0.28) quality of life. Conclusions. The issue of excessive daytime sleepiness should be considered in the management of sarcoidosis.
Bending Moment Characteristics of Hard Roof before First Breaking of Roof Beam Considering Coal Seam Hardening
Authors: Gu Shitan , Jiang Bangyou , Pan Yue , Liu Zheng
Published: July 2018

The mechanical properties of a coal seam affect the distribution of support pressure. Considering the strain hardening effect of coal seam, the support pressure relationship of three zones—softened, hardened, and elastic—of a coal seam with regard to a hard roof is proposed, and methods to determine an approximate expression for the support pressure of hardened zone of coal seam, the range of hardened zone, and the corresponding peak values of support pressure are provided. The deflection equations of a hard roof under three different support pressure relationships of coal seam before the first breaking were theoretically derived, and all the relevant integration constants were determined. Numerical examples of two cases are provided for calculating the bending moment of a hard roof and the support pressure of a coal seam. The analysis shows that as the working face advances, the maximum support pressure increases, the residual strength of coal seam at coal wall decreases, the overall deflection of roof gradually increases, the maximum bending moment of roof in the front of coal wall increases, and the advanced distance of roof bending moment peak gradually increases. As the depth of softened zone of coal seam increases, the similar conclusion is obtained, and the advanced distance of the roof bending moment peak increases at a relatively fast speed. Because the bending moment peak of hard roof is located near the support pressure peak in the softened zone of coal seam, the depth of softened zone of coal seam significantly affects the advanced distance of the bending moment peak of a roof. The actual advanced fracture distances of hard roof are distributed in a relatively broad range. The results indicate that there is a “large and long” type advanced fracture distance occurring in the actual stope. With the same overlying load and stope parameter conditions, the maximum support pressures of support roof in softened, hardened, and elastic zones considering a hardened coal seam are smaller than those in softened and elastic zones without hardening. However, the plumpness in front of the peak of the former support pressure curve is superior to that of the latter, and both the bending moment peak value and the advanced distance of bending moment peak of the former are higher than those of the latter.
Investigation of MicroRNA in Mitochondrial Apoptotic Pathway in Systemic Lupus Erythematosus
Authors: Su Yu-Jih , Tsai Nai-Wen , Kung Chia-Te , Wang Hung-Chen , Lin Wei-Che , Huang Chih-Cheng , Chang Ya-Ting , Su Chih-Min , Chiang Yi-Fang , Cheng Ben-Chung , Lin Yu-Jun , Lu Cheng-Hsien
Published: July 2018

Background. Accumulating evidence indicates that microRNAs play a pivotal role in the pathogenesis of systemic lupus erythematosus (SLE). This study tested the hypothesis that microRNA is associated with the mitochondrial apoptotic pathway in patients with SLE. Methods. Thirteen patients were in the clinical comparison study and microRNA study and overall 19 patients in the study of intracellular protein. Levels of microRNAs were determined by miRNeasy kit in 13 patients with SLE and 29 volunteer normal controls. Intracellular levels of caspase-9, caspase-10, MAVS, MDA5, and pIRF7 in mononuclear cells from 19 patiens and the SLE disease activity index (SLEDAI) were determined in all SLE patients. Correlation analyses were performed among microRNAs, intracellular adaptor proteins, and caspase levels and mean SLEDAI. Results. The ΔCT, defined by test reading difference between the target and the internal control microRNA (miR-451a), of miR-21-5p, miR-150-5p, and miR221-3p were significantly higher in plasma from SLE patients than in normal controls. miR-150-5pΔCT was positively correlated with both CRP and SLEDAI value. miR-150-5pΔCT was negatively associated with MAVS 70 kD. Caspase-10 protein levels were negatively associated with plasma miR-22-3pΔCT and miR-21-5pΔCT levels. Conclusions. Our study confirmed the hypothesis that these microRNAs were associated with the mitochondrial apoptotic pathway in SLE. miR-150-5pΔCT was positively associated with SLE disease activity and it was negatively correlated with MAVS 70 kD, which may facilitate viral survival and further enhance inflammation. On the other hand, miR-22-3pΔCT and miR-21-5pΔCT, were negatively correlated with caspase-10 levels, which may repress extrinsic apoptosis and increase cell survival.
Do the Th17 Cells Play a Role in the Pathogenesis of Leptospirosis?
Authors: Bandara Kanchana , Gunasekara Chinthika , Weerasekera Manjula , Marasinghe Chamil , Ranasinghe Nilantha , Fernando Neluka
Published: July 2018

Objectives. The aim of this study was to determine the level of five different pro- and anti-inflammatory cytokines to study the inflammatory response of leptospirosis. Materials and methods. The serum cytokine levels of IL-10, IL-17A, IL-21, IL-23, and TNF-α were investigated in 57 patients with leptospirosis and 12 healthy controls using a commercially available ELISA kit (Mabtech, Sweden). Statistical analysis was done using Graphpad Prism. Results. Elevation of serum IL-10 and IL-17A levels and significant elevation of serum IL-21 (p=0.002), IL-23 (p=0.002), and TNF-α (p=0.039) were observed among leptospirosis patients compared to the healthy control group. The two major complications observed among these patients were renal failure and liver involvement. Renal failure was significantly associated with elevation of IL-21 and IL-23, while patients with liver involvement had a significant elevation of IL-21, IL-23, and TNF-α. Conclusion. Elevation of IL-17A together with the significant elevation of IL-21 and IL-23 suggests a possible involvement of Th17 cells in the immunopathogenesis of leptospirosis.
Is Chronic Exposure to Low-Dose Organochlorine Pesticides a New Risk Factor of T-cell Immunosenescence?
Authors: Ryu Dong-Hee , Yu Hee Tae , Kim Se-A , Lee Yu-Mi , Hong Seon-Hui , Yoon Young-Ran , Kim Dae-Jung , Kim Hyeon-Chang , Moon Hyo-Bang , Shin Eui-Cheol , Lee Duk-Hee
Published: July 2018

Background: T-cell immunosenescence, a hallmark of an aging immune system, is potentially linked to the risk of developing cancer and other aging-related diseases. Chronic infection by cytomegalovirus (CMV) has been widely studied as a risk factor for T-cell immunosenescence, but the role of persistent chemicals has never been examined. As a typical example of persistent chemicals, we evaluated whether organochlorine pesticides (OCPs) are related to T-cell immunosenescence in the general population.

Methods: Serum concentrations of β-hexachlorocyclohexane, p,p′-DDT, p,p′-DDE, and trans-nonachlor were measured in 95 Korean adults ages 30 to 64 years. T-cell immunosenescence was assessed by the frequencies of CD8+CD57+, CD8+CD28−, CD4+CD57+, and CD4+CD28− T lymphocytes in 20 mL of fresh peripheral blood.

Results: The senescence of CD8+ T lymphocytes was the most consistently associated with OCPs. For quartiles of measurements of OCPs, adjusted mean percentages of CD8+CD57+ and CD8+CD28− T lymphocytes in the CD8+ T lymphocyte population were 23.9, 27.6, 31.0, and 38.7 (Ptrend < 0.01) and 25.6, 27.3, 28.0, and 35.5 (Ptrend = 0.02), respectively. When we compared the strength of the associations among OCPs, CMV IgG titer, and age, OCPs showed the strongest association with markers of immunosenescence. Importantly, the association between OCPs and immunosenescence markers was more prominent among participants without known risk factors, such as a young age or low CMV immunoglobulin G titer.

Conclusions: Chronic exposure to low-dose OCPs may be a new risk factor for T-cell immunosenescence.

Impact: T-cell immunosenescence may be one possible mechanism linking low-dose OCPs and many chronic diseases. Cancer Epidemiol Biomarkers Prev; 27(10); 1159–67. ©2018 AACR.
Detection and Genotyping of HPV DNA in a Group of Unvaccinated Young Women from Colombia: Baseline Measures Prior to Future Monitoring Program
Authors: Puerto Devi , Reyes Viviana , Lozano Cristina , Buitrago Lina , Garcia Diego , Murillo Raúl H. , Muñoz Nubia , Hernandez Gustavo A. , Sanchez Laura , Wiesner Carolina , Combita Alba L.
Published: July 2018

In 2012, Colombia launched human papillomavirus (HPV) vaccination program for girls ages 9 to 12, and in 2013, the target age was expanded to 9 to 17 years. Monitoring the changes of HPV infection prevalence among young women has been proposed as an endpoint for early assessment of HPV vaccination programs. However, the data on HPV prevalence in young ages are very limited. The purpose of this study was to determine the prevalence of HPV infection and the distribution of genotypes in a group of nonvaccinated women ages 18 to 25 years old in three Colombian cities as baseline for the monitoring of the HPV national vaccination program. A total of 1,782 sexually active women were included. Cervical smear samples were collected to perform the Pap smear and HPV DNA detection using a Linear Array HPV assay. Of the 1,782 specimens analyzed, 60.3% were positive for any HPV type; 42.2% were positive for high-risk HPV (HR-HVP) types, and 44.4% for low-risk HPV (LR-HPV) types. Multiple and single infections were identified in 37.1% and 23.2% of samples, respectively. HR-HPV types -16, -52, and -51 were the most predominant with proportions of 11.3%, 7.92%, and 7.9%, correspondingly. The prevalence for HR-HPV 16/18 was 14.4%. HR-HPV prevalence in women with abnormal cytology (75.16%) was higher than in women with normal cytology (38.6%). In conclusion, a high prevalence of HR-HPV was observed among younger women. This HPV type-specific prevalence baseline may be used to monitor postvaccination longitudinal changes and to determine its impact on HPV-related disease incidence in Colombia population. Cancer Prev Res; 11(9); 581–92. ©2018 AACR.
High Growth Rate of Pancreatic Ductal Adenocarcinoma in CDKN2A-p16-Leiden Mutation Carriers
Authors: Ibrahim Isaura S. , Wasser Martin N. , Wu Yinghui , Inderson Akin , de Vos tot Nederveen Cappel Wouter H. , Morreau Hans , Hes Frederik J. , Veenendaal Roeland A. , Putter Hein , Feshtali Shirin , van Mil Anneke M. , Gruis Nelleke A. , Tollenaar Rob A. , Bergman Wilma , Bonsing Bert A. , Vasen Hans F.A.
Published: July 2018

CDKN2A-p16-Leiden mutation carriers have a 20% to 25% risk of developing pancreatic ductal adenocarcinoma (PDAC). Better understanding of the natural course of PDAC might allow the surveillance protocol to be improved. The aims of the study were to evaluate the role of cystic precursor lesions in the development of PDAC and to assess the growth rate. In 2000, a surveillance program was initiated, consisting of annual MRI in carriers of a CDKN2A-p16-Leiden mutation. The study cohort included 204 (42% male) patients. Cystic precursor lesions were found in 52 (25%) of 204 mutation carriers. Five (9.7%) of 52 mutation carriers with cystic lesions and 8 (7.0%) of 114 mutation carriers without cystic lesions developed PDAC (P = 0.56). Three of 6 patients with a cystic lesion of ≥10 mm developed PDAC. The median size of all incident PDAC detected between 9 and 12 months since the previous normal MRI was 15 mm, suggesting an annual growth rate of about 15 mm/year. In conclusion, our findings show that patients with and without a cystic lesions have a similar risk of PDAC. However, cystic precursor lesions between 10 and 20 mm increase the risk of PDAC substantially. In view of the large size of the screen-detected tumors, a shorter interval of screening might be recommended for all patients. Cancer Prev Res; 11(9); 551–6. ©2018 AACR.