bluuebunny/crossref_metadata_2025 huggingface dataset:
Permeation of hydrocarbons through organosilane crosslinked LDPE
Authors: Berger Katrin , Keimel Christian , Helfer Eric , Haar Bernd , Eder Alexander , Mattausch Hannelore , Riess Gisbert
Published: June 2017

The importance of polymeric transportation systems has been steadily increasing over the years. It is a useful material in numerous applications, such as packaging, oil and gas pipes, and household items. One particular aspect of polyethylene (PE) is the permeability of small molecules, such as low‐molecular‐weight hydrocarbons. In the present study, PE sheets were crosslinked by grafting and subsequent hydrolysis of organosilanes during a reactive extrusion process. The formation of a network structure was characterized by sol/gel analysis and by rheological measurements. It is shown that as a result of crosslinking the permeation of linear alkanes through the PE is reduced. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45374.
A novel porous nanocomposite of aminated silica MCM‐41 and nylon‐6: Isotherm, kinetic, and thermodynamic studies on adsorption of Cu(II) and Cd(II)
Authors: Mohammadnezhad Gholamhossein , Soltani Roozbeh , Abad Saeed , Dinari Mohammad
Published: June 2017

Porous amine‐modified MCM‐41/Nylon‐6 nanocomposite (NH2‐MCM‐41/NY6 NC) was synthesized by a facile solution casting protocol, which was used as an effective adsorbent for the removal of Cu(II) and Cd(II) from aqueous media. The physicochemical properties of NH2‐MCM‐41/NY6 NC were studied by scanning and transmission electron microscopies, thermogravimetric analysis, etc. The influence of pH, adsorbent dose, contact time and initial concentration on adsorption performance were investigated in detail. Kinetic and isotherm parameters were evaluated and the data fitted well to the pseudo‐second order and Freundlich isotherm model, respectively. The maximum adsorption capacities of Cu(II) and Cd(II) were about 35.84 and 27.5 mg·g−1, respectively. The Kd of NH2‐MCM‐41/NY6 NC for Cu(II) (>
) and Cd(II) (>
) ions uptake in aqueous solution, showed very good values. Thermodynamic parameters suggest that the adsorption is a spontaneous process with an endothermic nature. According to the results obtained, we conclude that this novel porous NH2‐MCM‐41/NY6 NC could be used for the removal of heavy metal ions from an aqueous solution. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45383.
Synthesis of 5‐Acyl‐2‐Amino‐3‐Cyanothiophenes: Chemistry and Fluorescent Properties
Authors: Lugovik Kseniya I. , Eltyshev Alexander K. , Benassi Enrico , Belskaya Nataliya P.
Published: June 2017

Independent of the substrate structure and reaction conditions, 3‐amino‐2‐cyanothioacrylamides, which contain two active electrophilic centers, were shown to interact with various active halo methylene compounds under mild conditions to afford 5‐acyl‐2‐amino‐3‐cyanothiophenes as the only products. A series of new polyfunctional thiophene derivatives with a rare combination of functionalities were synthesized, and their photophysical properties were experimentally and computationally investigated. The calculated electronic characteristics of the ground and excited states were compared to the experimental results, which provided a good understanding of the relationship between the optoelectronic properties and the molecular structures. After absorption of light quanta, the systems populate an intramolecular charge‐transfer (ICT) Franck–Condon state, and emission occurs from a twisted ICT minimum.
Shape analysis of the cervical spinous process
Authors: Greiner Thomas M.
Published: June 2017

Most textbooks describe the bifid spinous process as a shape associated with the typical cervical vertebra. Somewhere later they may acknowledge that cervical vertebrae are not always bifid, and that its appearance may be asymmetric. A high incidence of bifid cervical spinous processes may be a human characteristic, but because of known racial/geographic variation it may not be a very good one. Rarely can one find a satisfactory explanation of the functional or developmental basis for this shape variation. This article explores the distinctive shape of the cervical spinous process. Analysis is based upon the spinous processes of the third through seventh cervical vertebrae from fifty individuals. Shape differences were evaluated using the techniques of geometric morphometrics. Statistical comparisons were based upon 1000 permutations of a MANOVA based analysis. Significant shape differences were identified among the cervical vertebrae. However, post hoc analysis failed to identify significant differences between the C3 and C4 and between the C4 and C5 spinous process shapes. Primary shape differences were due to the depth of the bifid separation and the length of the process. Vertebrae with shorter spinous processes tended to display a more pronounced bifid condition. Combined observations from this and several other investigations suggest that a combination of variation in the spinalis cervicis muscle and behavioral patterns associated with cervical load may provide the best explanation for the shape variation in the cervical spinous process. Clin. Anat. 30:894–900, 2017. © 2017 Wiley Periodicals, Inc.
Src family kinase phosphorylation of the motor domain of the human kinesin‐5, Eg5
Authors: Bickel Kathleen G. , Mann Barbara J. , Waitzman Joshua S. , Poor Taylor A. , Rice Sarah E. , Wadsworth Patricia
Published: June 2017

Spindle formation in mammalian cells requires precise spatial and temporal regulation of the kinesin‐5, Eg5, which generates outward force to establish spindle bipolarity. Our results demonstrate that Eg5 is phosphorylated in cultured cells by Src family kinases (SFKs) at three sites in the motor head: Y125, Y211, and Y231. Mutation of these sites diminishes motor activity in vitro, and replacement of endogenous Eg5 with phosphomimetic Y211 in LLC‐Pk1 cells results in monopolar spindles, consistent with loss of Eg5 activity. Cells treated with SFK inhibitors show defects in spindle formation, similar to those in cells expressing the nonphosphorylatable Y211 mutant, and distinct from inhibition of other mitotic kinases. We propose that this phosphoregulatory mechanism tunes Eg5 enzymatic activity for optimal spindle morphology.
Reproductive cycles in tropical intertidal gastropods are timed around tidal amplitude cycles
Authors: Collin Rachel , Kerr Kecia , Contolini Gina , Ochoa Isis
Published: June 2017

Reproduction in iteroparous marine organisms is often timed with abiotic cycles and may follow lunar, tidal amplitude, or daily cycles. Among intertidal marine invertebrates, decapods are well known to time larval release to coincide with large amplitude nighttime tides, which minimizes the risk of predation. Such bimonthly cycles have been reported for few other intertidal invertebrates. We documented the reproduction of 6 gastropod species from Panama to determine whether they demonstrate reproductive cycles, whether these cycles follow a 2‐week cycle, and whether cycles are timed so that larval release occurs during large amplitude tides. Two of the species (Crepidula cf. marginalis and Nerita scabricosta) showed nonuniform reproduction, but without clear peaks in timing relative to tidal or lunar cycles. The other 4 species show clear peaks in reproduction occurring every 2 weeks. In 3 of these species (Cerithideopsis carlifornica var. valida, Littoraria variegata, and Natica chemnitzi), hatching occurred within 4 days of the maximum amplitude tides. Siphonaria palmata exhibit strong cycles, but reproduction occurred during the neap tides. Strong differences in the intensity of reproduction of Cerithideopsis carlifornica, and in particular, Littoraria variegata, between the larger and smaller spring tides of a lunar month indicate that these species time reproduction with the tidal amplitude cycle rather than the lunar cycle. For those species that reproduce during both the wet and dry seasons, we found that reproductive timing did not differ between seasons despite strong differences in temperature and precipitation. Overall, we found that most (4/6) species have strong reproductive cycles synchronized with the tidal amplitude cycle and that seasonal differences in abiotic factors do not alter these cycles.
tert‐Butoxy‐Radical‐Promoted α‐Arylation of Alkylamines with Aryl Halides
Authors: Ueno Ryota , Ikeda Yuko , Shirakawa Eiji
Published: June 2017

In the presence of a tert‐butoxy radical precursor, the reaction of alkylamines with aryl halides was found to give α‐arylated alkylamines through homolytic aromatic substitution of the halogen atoms.
Hepatic stimulator substance resists hepatic ischemia/reperfusion injury by regulating Drp1 translocation and activation
Authors: Zhang Chao , Huang Jing , An Wei
Published: June 2017

Ischemia/reperfusion injury, induced by abnormal mitochondrial fission–related apoptosis, is a major concern in liver transplantation settings. Our previous studies have demonstrated that hepatic stimulator substance (HSS) is an antiapoptotic effector and could protect liver from ischemia/reperfusion injury. However, the underlying mechanism remains unclear. In the present study, we report that in vitro and in vivo HSS could regulate mitochondrial fission and hepatocyte apoptosis during liver ischemia/reperfusion injury by orchestrating the translocation and activation of dynamin‐related protein 1 (Drp1). Using a mouse model of ischemia/reperfusion‐induced liver injury, we found that HSS‐haploinsufficient (HSS+/−) mice displayed exacerbated liver damage based on their increased serum aminotransferase levels, cell structural destruction, and apoptosis levels compared to wild‐type (HSS+/+) littermates. Disruption of HSS markedly increased cyclin‐dependent kinase 1 (CDK1) and Bax expression, accompanied by elevated phosphorylated Drp1 and release of cytochrome c. In parallel in vitro studies, we found that HSS could inhibit the expression of CDK1 and that HSS inhibits hepatocyte apoptosis through its suppression of CDK1/cyclin B–mediated phosphorylation at Ser‐616 of Drp1, thereby decreasing Drp1 accumulation in mitochondria and Drp1‐mediated activation of the mitochondrial fission program. On the contrary, knockdown of HSS increased CDK1 as well as Drp1 phosphorylation and aggravated hepatocellular apoptosis. Mechanistic investigation showed that HSS was able to reduce the stability and translation of CDK1 mRNA by modulating the expression of several microRNAs (miRs), including miR‐410‐3p, miR‐490‐3p, and miR‐582‐5p. Conclusion: Our data reveal a novel mechanism for HSS in regulating the mitochondrial fission machinery and further suggest that modulation of HSS may provide a therapeutic approach for combating liver damage. (Hepatology 2017;66:1989–2001)
Prospero‐related homeobox 1 drives angiogenesis of hepatocellular carcinoma through selectively activating interleukin‐8 expression
Authors: Liu Yanfeng , Zhang Yonglong , Wang Shenghao , Dong Qiong‐Zhu , Shen Zhongliang , Wang Wei , Tao Shuai , Gu Chenjian , Liu Jing , Xie Youhua , Qin Lun‐Xiu
Published: June 2017

Angiogenesis has been proven to play an important role in the progression of hepatocellular carcinoma (HCC). However, the molecular mechanism underlying HCC angiogenesis is not well understood. In this study, Prospero‐related homeobox 1 (PROX1) was identified as a novel proangiogenic factor in HCC cell lines and tissues. A strong positive correlation was found between the levels of PROX1 and microvessel density in HCC tissues. Knockdown of PROX1 expression in HCC cells significantly inhibited the in vitro capillary tube formation by human vascular endothelial cells and in vivo angiogenesis of HCC, while overexpression of PROX1 in HCC cells induced the opposite effects. PROX1 and nuclear factor κB p65 expression levels were positively correlated in both HCC tissues and cell lines. PROX1 enhances the nuclear accumulation of p65 and stabilizes p65 by recruiting ubiquitin‐specific protease 7 to prevent p65 ubiquitination. Consequently, PROX1 activated nuclear factor κB signaling and selectively promoted expression of the proangiogenic interleukin‐8 (IL‐8) by epigenetically stimulating the IL‐8 promoter. Finally, progression of high PROX1 expression HCC in tumor xenograft mice could be effectively contained by an anti‐IL‐8 monoclonal antibody. Conclusions: We have identified PROX1 as a crucial promoter of HCC angiogenesis; our study provides an insight into PROX1's function in HCC progression and the potential therapeutic application of anti‐IL‐8 antibody in high PROX1 expression HCC patients. (Hepatology 2017;66:1894–1909)
Does breast MRI background parenchymal enhancement indicate metabolic activity? Qualitative and 3D quantitative computer imaging analysis
Authors: Mema Eralda , Mango Victoria L. , Guo Xiaotao , Karcich Jenika , Yeh Randy , Wynn Ralph T. , Zhao Binsheng , Ha Richard S.
Published: June 2017

Purpose

To investigate whether the degree of breast magnetic resonance imaging (MRI) background parenchymal enhancement (BPE) is associated with the amount of breast metabolic activity measured by breast parenchymal uptake (BPU) of 18F‐FDG on positron emission tomography / computed tomography (PET/CT).

Materials and Methods

An Institutional Review Board (IRB)‐approved retrospective study was performed. Of 327 patients who underwent preoperative breast MRI from 1/1/12 to 12/31/15, 73 patients had 18F‐FDG PET/CT evaluation performed within 1 week of breast MRI and no suspicious findings in the contralateral breast. MRI was performed on a 1.5T or 3.0T system. The imaging sequence included a triplane localizing sequence followed by sagittal fat‐suppressed T2‐weighted sequence, and a bilateral sagittal T1‐weighted fat‐suppressed fast spoiled gradient‐echo sequence, which was performed before and three times after a rapid bolus injection (gadobenate dimeglumine, Multihance; Bracco Imaging; 0.1 mmol/kg) delivered through an IV catheter. The unaffected contralateral breast in these 73 patients underwent BPE and BPU assessments. For PET/CT BPU calculation, a 3D region of interest (ROI) was drawn around the glandular breast tissue and the maximum standardized uptake value (SUVmax) was determined. Qualitative MRI BPE assessments were performed on a 4‐point scale, in accordance with BI‐RADS categories. Additional 3D quantitative MRI BPE analysis was performed using a previously published in‐house technique. Spearman's correlation test and linear regression analysis was performed (SPSS, v. 24).

Result

The median time interval between breast MRI and 18F‐FDG PET/CT evaluation was 3 days (range, 0–6 days). BPU SUVmax mean value was 1.6 (SD, 0.53). Minimum and maximum BPU SUVmax values were 0.71 and 4.0. The BPU SUVmax values significantly correlated with both the qualitative and quantitative measurements of BPE, respectively (r(71) = 0.59, P < 0.001 and r(71) = 0.54, P < 0.001). Qualitatively assessed high BPE group (BI‐RADS 3/4) had significantly higher BPU SUVmax of 1.9 (SD = 0.44) compared to low BPE group (BI‐RADS 1/2) with an average BPU SUVmax of 1.17 (SD = 0.32) (P < 0.001). On linear regression analysis, BPU SUVmax significantly predicted qualitative and quantitative measurements of BPE (β = 1.29, t(71) = 3.88, P < 0.001 and β = 19.52, t(71) = 3.88, P < 0.001).

Conclusion

There is a significant association between breast BPU and BPE, measured both qualitatively and quantitatively. Increased breast cancer risk in patients with high MRI BPE could be due to elevated basal metabolic activity of the normal breast tissue, which may provide a susceptible environment for tumor growth.

Level of Evidence: 3

Technical Efficacy: Stage 3

J. Magn. Reson. Imaging 2018;47:753–759.
Focal Liver Lesions: Real‐time 3‐Dimensional Contrast‐Enhanced Ultrasonography Compared With 2‐Dimensional Contrast‐Enhanced Ultrasonography and Magnetic Resonance Imaging
Authors: Lee Jung‐chieh , Yan Kun , Lee San‐kan , Yang Wei , Chen Min‐hua
Published: June 2017

Objectives

This study sought to evaluate the application of real‐time 3‐dimensional (3D) contrast‐enhanced ultrasonography (US) to diagnose focal liver lesions and to compare these results with those from 2‐dimensional (2D) contrast‐enhanced US and contrast‐enhanced magnetic resonance imaging (MRI).

Methods

Patients with focal liver lesions were examined by 2D contrast‐enhanced US, 3D contrast‐enhanced US, and contrast‐enhanced MRI for lesion characterization, and biopsies and comprehensive clinical diagnoses served as reference standards. The sensitivity, specificity, area under the receiver operating characteristic curve, and intermodality agreement were assessed. The number of contrast agent injections and lesions observed per injection were calculated for 3D and 2D contrast‐enhanced US. The number and display quality of the feeding arteries observed with 3D and 2D contrast‐enhanced US were assessed.

Results

A total of 117 patients with 151 focal liver lesions were enrolled, including 67 cases of hepatocellular carcinoma, 51 cases of liver metastasis, and 33 cases of benign liver lesions. No significant differences were found among the modalities. The sensitivity values for 3D contrast‐enhanced US, 2D contrast‐enhanced US, and contrast‐enhanced MRI were 96%, 95%, and 93%, respectively; the specificity values were 87%, 84%, and 89%; and the area under the receiver operating characteristic curve values were 0.92, 0.90, and 0.92. The intermodality agreement was excellent (κ > 0.77). Fewer contrast agent injections were needed, and more lesions and feeding arteries were more clearly displayed on 3D than 2D contrast‐enhanced US (P < .001).

Conclusions

Real‐time 3D contrast‐enhanced US is useful for diagnosing focal liver lesions and for observing feeding arteries with fewer contrast agent injections.
A Contrast‐Enhanced Ultrasonographic Study About the Impact of Long‐term Exercise Training on Mammary Tumor Vascularization
Authors: Faustino‐Rocha Ana I. , Gama Adelina , Oliveira Paula A. , Vanderperren Katrien , Saunders Jimmy H. , Pires Maria J. , Ferreira Rita , Ginja Mário
Published: June 2017

Objectives

This study aimed to evaluate the impact of long‐term exercise training on the vascularization of rat mammary tumors.

Methods

Female rats were divided into 4 groups: N‐methyl‐N‐nitrosourea (MNU) treated sedentary, MNU treated exercised, control sedentary, and control exercised. Tumor development was induced in the MNU groups by MNU administration. Exercised groups were trained for 35 weeks. Tumor vascularization was evaluated by pulsed Doppler and contrast‐enhanced ultrasonography.

Results

The pulsatility and resistive indices were slightly higher in the MNU sedentary group (P > .05). Mammary tumors mainly had centripetal and heterogeneous enhancement of the contrast, clear margins, and the presence of penetrating vessels. The MNU exercised group had a lower arrival time and time to peak and higher peak intensity, wash‐in, and wash‐out (P > .05). The area under the curve was similar between groups (P > .05).

Conclusions

The contrast‐enhanced ultrasonographic study did not detect differences in mammary tumor vascularization between MNU sedentary and MNU exercised groups previously detected by power Doppler imaging, B‐flow imaging, and immunohistochemistry.
Annual survival and seasonal hunting mortality of midcontinent snow geese
Authors: Calvert Anna M. , Alisauskas Ray T. , White Gary C.
Published: June 2017

Annual banding programs have allowed the estimation of key demographic parameters for many populations of harvested wildlife, yet they often provide little insight into vital rate variation among seasonally occupied habitats or among regions with differing hunting regulations. For lesser snow geese (Chen caerulescens caerulescens) in the midcontinent of North America, rapid growth in abundance and the consequent implementation of special conservation measures present a scenario where seasonal mortality estimates would be highly valuable. We evaluated variation in hunting mortality of adult and young geese among 3 seasons (autumn, winter, and spring) based on annual banding data from breeding colonies north and south of 60°N latitude, and seasonal hunting recoveries from the United States and Canada. Using band‐recovery models and data covering 1999 through 2015, we first estimated annual survival for geese of both age classes and breeding locations, and then subsequently used seasonal hunting recoveries to derive estimates of seasonal hunting mortality and annual non‐hunting mortality. Simulation models validated the accuracy of this approach. Hunting mortality in winter generally exceeded that during spring and autumn, but our estimates suggested that hunting mortality represented a small fraction of annual mortality for adult and young birds. Consistent with recent studies, our estimates pointed to a greater harvest effect for the smaller subarctic population breeding near southern Hudson Bay, Canada, than for the large arctic population breeding farther north. Although mean kill rates were higher for young than adult geese, natural mortality for young was high and temporally variable, implying that some hunting mortality experienced by young geese during their first year could be compensated by natural causes of death. Natural (non‐hunting) mortality and annual survival showed greater temporal variation than seasonal kill rates in adults and young geese, highlighting the importance of non‐harvest factors (e.g., climate, habitat, population density) to the dynamics of these populations. These novel estimates of seasonal kill rates and non‐hunting mortality contribute further support to the notion that internal dynamics of the lesser snow goose midcontinent population, including natural mortality and recruitment, currently influence population trajectory more than ongoing interventions through harvest management. © 2017 The Wildlife Society.
New upper bound on m‐time‐relaxed k‐broadcast graphs
Authors: Averbuch Amir , Peeri Irete , Roditty Yehuda
Published: June 2017

Broadcasting is a process in which an individual has an item of information which needs to be transmitted to all of the members in a network (which is viewed as a connected graph). k‐broadcasting is a variant of broadcasting in which each processor can transmit the message to up to k of its neighbors. Another variant of broadcasting is the concept of m‐time‐relaxed broadcasting, where we allow m additional time units, enabling one to decrease the number of edges in the communication network. The combination of m‐time‐relaxed and k‐broadcasting is studied in this article. The results shown here are an improvement on the upper bound obtained by Harutyunyan and Liestman, Discrete Math 262 (2003), 149–157, by constructing a connected graph, which admits m‐time‐relaxed k‐broadcasting for all n, and has fewer edges than the graph presented in Harutyunyan and Liestman, Discrete Math 262 (2003), 149–157. © 2017 Wiley Periodicals, Inc. NETWORKS, Vol. 70(2), 72–78 2017
Energy efficiency of data center operating practices: Server clustering, powering on/off, and bang–bang control
Authors: Cho Yongkyu , Ko Young Myoung
Published: June 2017

Data centers today account for up to 3% of all global electricity consumption and produce 200 million metric tons of . Hence, improving energy efficiency is an important operational concern. This article examines common operating practices such as server clustering, powering on/off, and bang–bang control in terms of energy efficiency. Extending the mixed integer programming (MIP) formulation in a previous research study, we introduce new constraints reflecting the operating practices adopted for operational convenience. We develop an algorithmic strategy for constructing energy efficient clusters of servers using two upper bounds on the cluster size. Numerical experiments show that server clustering and bang–bang control do not diminish energy efficiency, and that powering on/off by itself is insufficient. Our results produce a conclusion that differs from the published literature on data center design and operations. © 2017 Wiley Periodicals, Inc. NETWORKS, Vol. 71(2), 107–119 2018
Targeted Calorie Message Promotes Healthy Beverage Consumption Better than Charity Incentive
Authors: Policastro Peggy , Palm Taylor , Schwartz Janet , Chapman Gretchen
Published: June 2017

Objective

Sugar‐sweetened beverage (SSB) consumption is cited as a major contributor to the U.S. obesity epidemic. The objective of this paper was to leverage insights from behavioral economics to examine whether nudges would entice college students to save meal calories by choosing water over SSBs.

Methods

Three message‐based nudge interventions, with washout periods between, were used during the 7‐week study. Calorie savings (self‐interest), charity (prosocial), or charity‐plus‐calorie message posters were displayed in a college‐based food franchise. Multilevel logistic regressions compared the proportions of students choosing water during three experimental conditions. This study assessed whether the frequency of dining establishment visits over the study period moderated effects of the experimental conditions on beverage choices. Multiple data points from the same customer were treated as repeated measures.

Results

A total of 2,393 unique students purchased 6,730 meals. Posters displaying calorie information increased water choice relative to washout periods, while the poster without calorie information (charity only) had no effect. Controlling for fixed effects produced the same results. The calorie message poster influenced less frequent diners more than frequent diners.

Conclusions

Food‐service operations can nudge college students to substitute water for SSBs with a simple calorie‐based message to save hundreds of calories per meal.
BIAN‐Fe(η6‐C6H6): Synthesis, characterization, and l‐lactide polymerization
Authors: Brown Lauren A. , Wekesa Francis S. , Unruh Daniel K. , Findlater Michael , Long Brian K.
Published: June 2017

The α‐diimine‐ligated Fe‐complex, BIAN‐Fe(C6H6), was synthesized and evaluated for the polymerization of l‐lactide. Characterization of BIAN‐Fe(C6H6) reveals that it is redox non‐innocent and suggests that it is an Fe(I) species bearing a radical‐anionic ligand. We will demonstrate that BIAN‐Fe(C6H6) is active for the ring‐opening polymerization of l‐lactide, and that polymer is produced with, or without, the use of an added external initiator. Interestingly, very high molecular weight polymers are produced in the absence of external initiator whereas polymer molecular weights that agree with theoretical calculations are produced in the presence of external initiator. To the best of our knowledge, BIAN‐Fe(C6H6) is the first Fe‐based α‐diimine catalyst reported to be active for the polymerization of l‐lactide. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2824–2830
Genomic and non-genomic effects of androgens in the cardiovascular system: clinical implications
Authors: Lucas-Herald Angela K. , Alves-Lopes Rheure , Montezano Augusto C. , Ahmed S. Faisal , Touyz Rhian M.
Published: June 2017

The principle steroidal androgens are testosterone and its metabolite 5α-dihydrotestosterone (DHT), which is converted from testosterone by the enzyme 5α-reductase. Through the classic pathway with androgens crossing the plasma membrane and binding to the androgen receptor (AR) or via mechanisms independent of the ligand-dependent transactivation function of nuclear receptors, testosterone induces genomic and non-genomic effects respectively. AR is widely distributed in several tissues, including vascular endothelial and smooth muscle cells. Androgens are essential for many developmental and physiological processes, especially in male reproductive tissues. It is now clear that androgens have multiple actions besides sex differentiation and sexual maturation and that many physiological systems are influenced by androgens, including regulation of cardiovascular function [nitric oxide (NO) release, Ca2+ mobilization, vascular apoptosis, hypertrophy, calcification, senescence and reactive oxygen species (ROS) generation]. This review focuses on evidence indicating that interplay between genomic and non-genomic actions of testosterone may influence cardiovascular function.
Nintedanib, a triple tyrosine kinase inhibitor, attenuates renal fibrosis in chronic kidney disease
Authors: Liu Feng , Wang Li , Qi Hualin , Wang Jun , Wang Yi , Jiang Wei , Xu Liuqing , Liu Na , Zhuang Shougang
Published: June 2017

Nintedanib (BIBF1120) is a triple kinase inhibitor of platelet-derived growth factor receptor (PDGFR), fibroblast growth factor receptors (FGFR), vascular endothelial growth factor receptor (VEGFR), and Src family kinase, which has recently been approved by FDA to treat idiopathic pulmonary fibrosis. Whether it affects renal fibrosis remains unknown. Here, we demonstrated that administration of nintedanib immediately or 3 days after unilateral ureteral obstruction (UUO) injury and with folic acid (FA) injection attenuated renal fibrosis and inhibited activation of renal interstitial fibroblasts. Delayed administration of nintedanib also partially reversed established renal fibrosis. Treatment with nintedanib blocked UUO-induced phosphorylation of PDGFRβ, FGFR1, FGFR2, VEGFR2, and several Src family kinases including Src, Lck, Lyn as well as activation of signal transducer and activator of transcription-3 (STAT3), nuclear factor-κB (NF-κB), and Smad-3 in the kidney. Furthermore, nintedanib inhibited UUO-elicited renal proinflammatory cytokine expression and macrophage infiltration. These data indicate that nintedanib is a potent anti-fibrotic agent in the kidney and may hold therapeutic potential as a treatment of chronic fibrotic kidney disease.
miR-223 represents a biomarker in acute and chronic liver injury
Authors: Schueller Florian , Roy Sanchari , Loosen Sven Heiko , Alder Jan , Koppe Christiane , Schneider Anne Theres , Wandrer Franziska , Bantel Heike , Vucur Mihael , Mi Qing-Sheng , Trautwein Christian , Luedde Tom , Roderburg Christoph
Published: June 2017

Background: Dysregulation of miRNAs has been described in tissue and serum from patients with acute and chronic liver diseases. However, only little information on the role of miR-223 in the pathophysiology of acute liver failure (ALF) and liver cirrhosis is available.

Methods: We analysed cell and tissue specific expression levels as well as serum concentrations of miR-223 in mouse models of acute (hepatic ischaemia and reperfusion, single CCl4 injection) and chronic (repetitive CCl4 injection, bile duct ligation (BDL)) liver diseases. Results were validated in patients and correlated with clinical data. The specific hepatic role of miR-223 was analysed by using miR-223−/− mice in these models.

Results: miR-223 expression was significantly dysregulated in livers from mice after induction of acute liver injury and liver fibrosis as well as in liver samples from patients with ALF or liver cirrhosis. In acute and chronic models, hepatic miR-223 up-regulation was restricted to hepatocytes and correlated with degree of liver injury and hepatic cell death. Moreover, elevated miR-223 expression was reflected by significantly higher serum levels of miR-223 during acute liver injury. However, functional in vitro and in vivo experiments revealed no differences in the degree of liver cell death and liver fibrosis as miR-223−/− mice behaved identical with wild-type (wt) mice in all tested models.

Conclusion: miR-223 represents a promising diagnostic marker in a panel of serum markers of liver injury. Together with previously published data, our results highlight that the role of miR-223 in the pathophysiology of the liver is complex and needs further analysis.
Expression ofmiR-23ainduces telomere shortening and is associated with poor clinical outcomes in patients with coronary artery disease
Authors: Satoh Mamoru , Nasu Takahito , Takahashi Yuji , Osaki Takuya , Hitomi Sho , Morino Yoshihiro , Nakamura Motoyuki
Published: June 2017

Telomeric repeat binding factor (TRF) 2 (TRF2) plays an important role in telomere maintenance. miR-23a may directly inhibit TRF2 expression, thereby, inducing telomere shortening and cellular senescence. The present study aimed to determine whether miR-23a and TRF2 are expressed in patients with coronary artery disease (CAD), and whether pitavastatin might affect these levels. The present study included 104 patients with CAD and 50 controls. Patients with CAD were randomly divided into two subgroups (a moderate lipid lowering therapy (LLT) group and an aggressive LLT group). Peripheral blood mononuclear cells (PBMCs) were taken from patients with CAD and from controls at baseline and after 12 months. Levels of miR-23a were higher in the CAD group than in the controls. Levels of TRF2 protein were lower in the CAD group than in the controls. Our randomized clinical study showed that aggressive LLT decreased miR-23a and increased TRF2 levels, whereas moderate LLT generated no change in these levels. Our transfected cell model showed that miR-23a controlled TRF2 expression. After a mean follow-up of 339 days, cardiovascular events were associated with high miR-23a, low TRF2 or low relative telomere length. Multivariate analysis showed that levels of miR-23a (RR: 4.9, 95% CI: 1.9–14.3) were a strong predictor of cardiovascular events after adjustment for baseline characteristics. In conclusion, elevated levels of miR-23a play an important role in coronary atherosclerosis via down-regulated TRF2, and may provide important prognostic information in patients with CAD. Additionally, aggressive LLT may prevent telomere erosion via down-regulated miR-23a.
Eigenvalue ratio based blind spectrum sensing algorithm for multiband cognitive radios with relatively small samples
Authors: Yang Xi , Lei Kejun , Hu Li , Cao Xiuying , Huang Xiaoyu
Published: June 2017

The multiband detection problem in relatively small sample scenarios where the number of subbands is comparable to the number of samples in magnitude is described. Combined with the sequential hypothesis testing, an eigenvalue ratio based method is proposed for the multiband spectrum sensing (MSS). As the distribution of the new statistic when only noise is present can be precisely obtained by using the random matrix theory, the proposed method is able to reliably set the theoretical threshold, and outperforms the traditional MSS methods based on information theoretic criteria and principal component analysis, especially in the cases with small samples. Meanwhile, the proposed method belongs to a blind detection scheme and can be used in cases without prior knowledge of the primary signal, the channel and the noise. Simulation results show the superiority of the proposed method.
Reply to: Comments on ‘State feedback control design of continuous‐time switched affine systems’
Authors: Deaecto Grace S. , Santos Guilherme C.
Published: June 2017

The authors present some aspects that worth to be taken into account in a comparative study on performance derived from min‐type and max‐type switching functions for continuous‐time switched affine systems. In this direction, this note puts in evidence the comparisons made by Deaecto and Santos in 2015 about the results of Trofino et al. in 2012 whose illustrative example was enhanced by Scharlau et al. in 2017 by optimising some free parameters. With the optimisation, the guaranteed costs became smaller than the ones of Deaecto and Santos in 2015 for the case where the switching function depends only on the state variable. It is shown that this situation can occur and it is in complete accordance with the theoretical results reported by Deaecto and Santos in 2015.
Direct flux and current vector control for induction motor drives using model predictive control theory
Authors: Odhano Shafiq , Bojoi Radu , Formentini Andrea , Zanchetta Pericle , Tenconi Alberto
Published: June 2017

The study presents the direct flux and current vector control of an induction motor (IM) drive, which is a relatively newer and promising control strategy, through the use of model predictive control (MPC) techniques. The results highlight that the fast flux control nature of direct flux control strategy is further enhanced by MPC. Predictive control is applied in two of its variants, namely the finite control set and modulated MPC, and the advantages and limitations of the two are underlined. This work also highlights, through experimental results, the importance of prioritising the flux part of the cost function which is particularly significant in the case of an IM drive. The performance of the MPC‐based approach is compared with the proportional–integral controller, which also prioritises the flux control loop, under various operating regions of the drive such as in the flux‐weakening regime. Simulations show the performance expected with different control strategies which is then verified through experiments.
Thermo‐electromagnetic analysis of radial HTS magnetic bearings using a semi‐analytical method
Authors: Naseh Mojtaba , Heydari Hossein
Published: June 2017

Nowadays, after passing more than three decades from discovery of high‐temperature superconductors, they are widely used in different fields including power industry. High‐temperature superconducting (HTS) bearing is an electromagnetic machine that provides frictionless operation and intrinsic stability without requiring control equipment. Before entering to the fabrication stage, an accurate simulating model can satisfactorily reveal many of practical considerations. This work is based on the results of their previous study, delving into time steps of multi‐physical simulations juxtaposing electromagnetic and thermal characteristics of an HTS bearing. This is attainable by using multi‐physics analysis of radial HTS bearings based on a semi‐analytical method called variational iteration method (VIM). This is accomplished by coupling of the Maxwell equations and thermal equilibrium. The electrical behaviour of the superconductor is described by means of a B–T‐dependent modified E–J power‐law relation. To verify VIM results, the multi‐physics equations are also numerically solved using finite‐element method. In this research, two case studies are examined; failure of the cryogenic system and incorporating new materials in the stator part of the bearing in order to improve the cooling efficiency.
Modelling, diagnosis, and tolerant control of phase‐to‐phase fault in switched reluctance machine
Authors: Han Guoqiang , Chen Hao , Shi Xianqiang
Published: June 2017

Winding insulation degradation may lead to phase‐to‐phase fault in switched reluctance machines (SRMs). First, the fault modes are described considering the connected sequence of the coils and the fault behaviours are analysed in details. Second, the equivalent circuit of three‐phase windings is represented and the faulty SRM is modelled based on the derived electromechanical equations. Third, the locations of three current sensors are optimised to calculate the incoming line current and outgoing line current of each phase without utilisation of any extra hardware. The phase‐to‐phase fault can be detected and located by monitoring the residuals between the two line currents during motor operation. Forth, to improve the post‐fault operation performance of the motor, a triple closed‐loop control scheme aiming at suppressing the short‐circuit current is conducted by modifying the switching states of power transistors. Finally, simulations and comparative experiments on a three‐phase 12/8 structure SRM validate the effectiveness of the proposed methods.
Multi‐agent transactive energy management system considering high levels of renewable energy source and electric vehicles
Authors: Astero Poria , Choi Bong Jun , Liang Hao
Published: June 2017

The future smart grids (SGs) consist of considerable amount of renewable energy sources (RESs), electrical vehicles (EVs), and energy storage systems (ESSs). The uncertainties associated with EVs and uncontrollable nature of RESs have magnified voltage stability challenges and the importance of an effective energy management system (EMS) in SGs as a practical solution. This study presents a multi‐agent transactive energy management system (TEMS) to control demand and supply in the presence of high levels of RESs and EVs, and maximises profit of each participant in addition to satisfying voltage regulation constraints. For this purpose, a real‐time pricing is considered based on Cournot oligopoly competition model for demand and merit order effect for production to compensate RESs’ fluctuations in real time by an indirect control method. Simulations are conducted in the modified IEEE 37‐bus test system with 1141 customers, 670 EVs, two solar plants, four wind turbines, and one ESS. The results show that the proposed multi‐agent TEMS can indirectly control EVs, elastic loads, and ESSs to balance the RESs oscillation, minimise customers cost, and regulate voltage in a real‐time manner.
Fast reliability evaluation method for composite power system based on the improved EDA and double cross linked list
Authors: Liu Wenxia , Cheng Rui , Xu Yahui , Liu Zongqi
Published: June 2017

To improve the computational efficiency of Monte Carlo simulation in composite power systems reliability evaluation, this study presents a method based on the improved estimation of distribution algorithm (EDA) and double cross linked list. Compared to traditional techniques, this method is comprehensively improved in the stage of both sampling and state evaluation. In the sampling stage, the population‐based incremental learning algorithm is presented, where the probability vector is updated based on the distribution characteristics of excellent samples in population of previous generations. Meanwhile, setting a limit to the probabilities of elements in normal state and mutation strategy are introduced, which improves the excellent characteristics of the population. In the state evaluation stage, the state search and match process is speed up by utilising the intelligent storage technology based on the double across linked list. It avoids calling the optimal power flow for the same state repeatedly. Finally, the proposed method is tested in IEEE RTS 79. As the result shows, compared with other methods ever used in reliability evaluation, this method is not only more efficient in computation but also more accurate. Thus, the proposed method is proved to be reliable and effective.
Synthesis of sparse concentric ring arrays based on Bessel function
Authors: Zhao Xiaowen , Zhang Yunhua , Yang Qingshan
Published: June 2017

In this study, a novel strategy is proposed for synthesis of sparse concentric ring arrays composed of uniformly excited elements. The synthesis problem herein is aimed at determining the sparse ring radii and the corresponding number of elements equally spaced on each ring simultaneously in order to produce circularly symmetric patterns. By using the proposed method, the above synthesis problem can be simply transformed to a single‐type‐variable optimisation problem since the relationship between the sparse ring radius and the element number is derived according to the properties of Bessel function. The proposed method is very efficient and flexible for synthesising direct radiating arrays and/or the scanned ones. Numerical experiments are conducted to validate the effectiveness of the proposed method. Compared with other methods, the proposed method can obtain circularly symmetric patterns using fewer elements. On this basis, the comparison of sparse array and thinning array is given through numerical experiment. Meanwhile, a scanned sparse array of 908 elements is synthesised in a circular aperture of 25λ diameter with invariant peak sidelobe level of −28.9 dB, which can steer the beam from 0° to 30° in elevation and from 0° to 360° in azimuth.
Compact size cognitive radio with non‐ and uni‐planar parasitic coupled section for UWB and WLAN/WiMax application
Authors: Karamzadeh Saied , Rafiei Vahid , Saygin Hasan
Published: June 2017

Due to the requirements of increased bandwidth and data transfer rate in wireless communication, cognitive radio (CR) has been proposed as a solution to the spectrum scarcity problem. Regarding the many advantages that ultra‐wideband (UWB) antennas offer, they could be used in CR systems. Simultaneously, by designing a band reject filter for avoiding interference with other applications, like wireless local area network (WLAN) and Worldwide Interoperability for Microwave Access (WiMAX), safety communication can be provided. In this work, two novel CRs (so that secondary ports are as non‐planar and uni‐planar parasitic antennas shapes) are presented. Each antenna consists of two ports at the opposite sides; one of them plays as UWB port (first work: 3.1–10.6 GHz and second work: 2.98–11.83 GHz) with filtered WLAN/WiMAX (first work: 4.9–5.8 GHz and second work: 4.9–6.08 GHz) and the other one supports filtered frequency bandwidth (first work: 4.8–6.2 GHz and second work: 5.1–6 GHz). Size reduction occurred in this work with both structures having the same size of 25 × 25 × 0.8 mm3. The designed antennas were measured and results of antennas have agreed well with the simulation analysis.
Switchable dual/triple‐band circularly polarised slot antenna by using artificial transmission line
Authors: Ghaffarian Mohammad Saeid , Moradi Gholamreza , Mousavi Pedram
Published: June 2017

A single‐feed dual and triple‐band reconfigurable planar single layer circularly polarised (CP) slot antenna is presented. This novel low‐cost slot antenna composed of L‐shaped feeding stub with modified open split‐ring resonator (MOSRR) and complementary split‐ring resonator (CSRR). Multi‐frequency operation with CP radiation characteristics is achieved by using artificial exciting stub with combining MOSRRs along microstrip feeding line and defecting CSRRs on it. By inserting two PIN diodes inside the MOSRRs, several wireless frequency bands over 2.4–5.5 GHz with capability of switching are obtained. The simulated and measured results show that the proposed antenna can switch between two states including one dual‐band mode (3–3.45/4.5–5.2 GHz) and one triple‐band mode (2.3–2.43/3.3–3.43/5.2–5.42 GHz) that covers most of the commercial wireless communication systems, such as WLAN (IEEE 802.11), LTE and WiMAX. Different characteristics of each state such as impedance and 3 dB axial ratio bandwidths, radiation patterns and gains of the proposed antenna will be presented.
VHF/UHF broadband four‐way power combiner/divider using 0° hybrid and impedance transformer based on transmission lines
Authors: Lee Hwiseob , Lim Wonseob , Bae Jongseok , Lee Wooseok , Kang Hyunuk , Lee Kang‐Yoon , Hwang Keum Cheol , Yang Youngoo
Published: June 2017

This study presents a broadband four‐way power combiner/divider for very high frequency (VHF) to ultra‐high frequency (UHF) bands using hybrids and impedance transformers based on transmission lines. The hybrids were used as in‐phase power combiners or dividers, and 1 : 4 impedance transformers were adopted to transform the impedance so that all input and output ports had a 50 Ω impedance. Each component was analysed using equivalent circuits. The overall size of the implemented four‐way power combiner/divider module was . Based on the measured S‐parameters, an ultra‐broad bandwidth from 8.0 to 600 MHz was achieved with an insertion loss <1.0 dB, reflection coefficients below −10.0 dB, isolation among the ports less than −15.0 dB, and magnitude and phase imbalances less than ±0.1 dB and , respectively.