bluuebunny/crossref_metadata_2025 huggingface dataset:
A multi‐band rectifier with modified hybrid junction for RF energy harvesting
Authors: Li Zihong , Zeng Miaowang , Tan Hong‐Zhou
Published: March 2018

This article presents a novel multi‐band rectifier utilizing modified hybrid structure for radio frequency (RF) energy harvesting. The proposed multi‐band rectifier consists of a modified hybrid junction and three rectifying branches. The rectifying branches are placed inside the modified hybrid to reduce the layout size. The proposed multi‐band rectifier is designed for GSM‐1800, UMTS‐2100, and Wi‐Fi bands. Measured peak efficiency of the proposed rectifier reaches 61.7% at 9 dBm input power level. The results show a good overall performance on operation bands, efficiency, output voltage, and layout size. The proposed rectifier can be used for various RF energy harvesting applications, especially in the multi‐source condition.
Temperature‐dependent characteristics of a RTD‐based microwave push‐push oscillator
Authors: Lee Kiwon , Jeong Yongsik
Published: March 2018

In this letter, the temperature dependence of a microwave push–push oscillator based on a resonant tunneling diode (RTD) has been investigated from 30°C to 80°C. An output power characteristic curve of the second‐harmonic RTD oscillator has been shifted to the higher bias voltages as temperature increases. An oscillation frequency shift of ΔfOSC has been obtained to be –9.8 MHz/K which is equivalent to the ΔfOSC of –4.9 MHz/K at the fundamental oscillation frequency of 14.45 GHz. To authors’ knowledge, this is the first report on the temperature dependent characteristics of the second‐harmonic push–push RTD oscillator.
Pseudo‐color enhancement and its segmentation for femtosecond laser spot image
Authors: Wang Fu‐Bin , Wu Chen , Liu Yang , Feng Ding , Tu Paul
Published: March 2018

When using femtosecond laser processing silicon wafer, arises laser spot along with the plasma diffraction. Comparatively studied the spot images of silicon wafer which was in three processing movement states as follows: towards the left, stop, towards the right, found that the three dimensional Gauss mean ablation energy of spot image almost kept the same, this provides experimental support for femtosecond laser feedback processing based on Gauss energy of spot image. Then the following image enhancement strategies are proposed: pseudo color transformation for spot image, color decomposition in RGB space and image superposition of G component, and the quality of the spot image is improved. In addition, adopted the method of Particle Swarm Optimization (PSO) or K‐means respectively, analyzed the segmentation effect for spot image: through traversal compares the gray value of image pixel and fitness function, realized the spot image segmentation with PSO, and the clustering and segmentation for data cluster of image pixel was realized by K‐means. Finally, overcome the shortcomings of PSO and K‐means, the ideal segmentation for spot target image is realized by combining the two methods.
SIW‐based cavity‐backed self‐diplexing antenna with plus‐shaped slot
Authors: Nandi Sourav , Mohan Akhilesh
Published: March 2018

A substrate integrated waveguide (SIW)‐based planar cavity‐backed self‐diplexing antenna, designed for X‐band applications, is presented in this article. The proposed antenna is fed by two orthogonal 50 Ω microstrip lines. Two orthogonal rectangular slots, combination of which makes a plus‐shaped slot, of different lengths are etched on the top of the SIW cavity. Due to the unequal arm lengths of the plus‐shaped slot, the antenna radiates at two distinct frequencies. An isolation of better than 20 dB is achieved between the two ports and hence, the proposed antenna exhibits self‐diplexing characteristics. The antenna offers a gain of 5.7 dBi and 5.94 dBi at 8.55 GHz and 9.77 GHz, respectively.
Low profile CPW fed slotted planar inverted cone ultra‐wide band antenna for WBAN applications
Authors: Nadeem Muhammad , Khan Ali Nawaz , Ali Khan Asim , Azim Tayyab
Published: March 2018

This letter presents the design and analysis of a smart and low profile Ultra‐Wideband Slotted Planar Inverted Cone Antenna. The proposed slotted PICA has low profile (0.4 λ mm2 × 0.4 λ mm2) as compared to other existing designs and its operational bandwidth is from 3 GHz to 18 GHz. The simulated and measured results concur with acceptable return loss of better than 10 dB throughout the operational bandwidth. The radiation pattern of the antenna is omnidirectional and it has maximum Gain of 3.2 dB when placed close to human body, making it compatible for WBAN applications.
Fiber‐based measurement of temporal intensity and phase profiles of an optical telecommunication pulse through self‐phase modulation
Authors: Baudin Killian , Audo Frédéric , Finot Christophe
Published: March 2018

We propose and experimentally validate an all‐fiber based approach to characterize the phase and intensity profiles of optical pulses. Based on three optical spectra affected by different levels of self‐phase modulation, we were able to reconstruct the temporal details of pulses typical of optical telecommunications.
Leaf‐shaped CPW‐fed UWB antenna with triple notch bands for ground penetrating radar applications
Authors: Kundu Surajit , Jana Sanjay Kumar
Published: March 2018

A compact (38.31 mm × 34.52 mm × 0.8 mm) leaf shaped CPW fed ultra‐wideband antenna is proposed. The antenna gives wide impedance bandwidth from 2.58 GHz to 11.62 GHz with sharp triple notch bands (3.28 GHz–3.82 GHz, 5.12 GHz–5.4 GHz, and 5.7 GHz–6 GHz) to eliminate interference from co‐existing IEEE 802.16 WiMAX (3.3 GHz–3.8 GHz), IEEE 802.11y (3.65 GHz–3.69 GHz), IEEE 802.11a WLAN (5.15 GHz–5.35 GHz and 5.725 GHz–5.825 GHz), and IEEE 802.11p DSRC (5.85 GHz–5.925 GHz) bands. The antenna provides minimal gain variation (2–5 dBi), flat group delay response and non‐varying transfer function with high average efficiency of 88% in the pass band. Significant drop in gain and efficiency, nonlinearity in transfer function, and high variation in group delay are observed at notch bands. Antenna VSWR, and efficiency are measured in close proximity of sand, wood, and glass. Satisfactory results ensure its ability to work as Ground penetrating radar antenna.
Simplified fiber Bragg grating‐based temperature measurement system design with enhanced high signal‐to‐noise ratio
Authors: Yucel Muret , Torun M.
Published: March 2018

In this study, a temperature measurement was performed by determining the linear slope in the transmission spectrum of fiber Bragg grating (FBG) and by designing a temperature measurement system with the density fluctuation of a stationary continuous wave (CW) laser light on this line. The measuring range, which may change depending on the transmission spectrum of the FBG, was determined to be 12°C for this study and measurements were performed with 0.06°C accuracy. Gaussian fitting with negligible time loss and high noise immunity increased the signal‐to‐noise ratio (SNR) ratio to 37.5 dB. A simple, cost‐ efficient, high‐speed, and high SNR, ergonomic, compact temperature measurement system was created with the suggested slope technique and by using a very limited number of fiber optic components.
A leaf‐shaped CPW‐fed UWB antenna for GPR applications
Authors: Kundu Surajit , Jana Sanjay Kumar
Published: March 2018

A new co‐planar waveguide fed UWB antenna with transitions in feed line is proposed in this article. A good agreement is found in between simulated and measured results of the proposed design. The antenna provides a bandwidth improvement of more than 120% with min. group delay variation, high efficiency of 88%, and gain variation of 2–5 dBi. The antenna pattern is omnidirectional in H‐plane and monopole like in E‐plane. The proposed antenna is also tested in close proximity of soil to establish its ability for GPR applications.
A 40 GHz on‐chip power combine load for mm‐wave power amplifier
Authors: Lin Jiafu , Zhang Gary , Boon Chirn Chye
Published: March 2018

Millimeter‐wave (Mm‐Wave) communication have been considered as one of the most potential candidate of the 5th generation communication (5G). However, the low breakdown voltage of CMOS challenges RF circuits design in various aspects especially for power amplifier (PA). The maximum available power from an unit transistor is limited by device characteristic thus power combining methods have been extensively investigated. This paper presents an on‐chip power combine load that can provide impedance transformation together with power combining for Mm‐Wave CMOS PA. A two‐way λ/6 power combine load has been implemented at 40 GHz on 0.18 µm CMOS technology, the measured return loss of each port is better than 15 dB and the loss is lower than 1.5 dB while isolation is better than 20 dB with a compact size (0.08 mm2).
Compact 4 element Sierpinski Knopp fractal UWB MIMO antenna with dual band notch
Authors: Rajkumar S. , Selvan Krishnasamy T. , Rao P.H.
Published: March 2018

In this communication, a 4 element ultra‐wide band (UWB) multiple‐input multiple‐output (MIMO) antenna is presented. The total size of the proposed antenna is 40 × 40 mm2. A novel Sierpinski Knopp fractal geometry is used in the antenna radiator design to accomplish miniaturization. The antenna elements are placed orthogonal to each other. The spacing between any pair of elements is 0.11 λ (λ being the free space wavelength at 7.15 GHz). A CSRR shape like slot is etched on the radiating element to achieve dual band notch characteristics at WiMax 3.5 GHz and WLAN 5.4 GHz regions. The proposed antenna operates from 2.6 to 10.6 GHz, exhibiting a reflection coefficient S11 < −10 dB and an isolation better than 20 dB. The MIMO antenna does not require any additional structure to improve isolation. Envelope correlation coefficient (ECC) and capacity loss (CL) are calculated to evaluate the diversity performance of the proposed antenna. The measured values exhibit better match with the simulated results.
Design and analysis of a novel dual trapezoidal slot‐based rectangular microstrip antenna for wide area network using WiMax application
Authors: Raviteja G. Viswanadh
Published: March 2018

In this article, a novel microstrip rectangular patch antenna is designed which involves dual trapezoidal slots. The proposed microstrip patch antenna is used in the S band range of 2–4 GHz, used for various wireless applications. The resonant frequency is calculated theoretically at 3.5 GHz with patch dimensions being 25.4 mm × 19.4 mm in terms of width × length (in mm). Using the theoretical parameters, the proposed patch antenna is designed using HFSS software. The results are also compared to the conventional regular patch antenna. The results show that the proposed patch antenna with dual trapezoidal slot has better return loss and VSWR and can be used for WiMax application services. The observations and findings are tabulated.
Stratified spherical model for microwave imaging of the brain: Analysis and experimental validation of transmitted power
Authors: Bjelogrlic Mina , Volery Maxime , Fuchs Benjamin , Thiran Jean‐Philippe , Mosig Juan R. , Mattes Michael
Published: March 2018

This work presents the analysis of power transmission of a radiating field inside the human head for microwave imaging applications. For this purpose, a spherical layered model composed of dispersive biological tissues is investigated in the range of (0.5–4) GHz and is confronted to experimental verification.
CEST‐MRI studies of cells loaded with lanthanide shift reagents
Authors: Ferrauto Giuseppe , Di Gregorio Enza , Delli Castelli Daniela , Aime Silvio
Published: March 2018

Purpose

Magnetic resonance imaging has been used extensively to track in vivo implanted cells that have been previously labeled with relaxation enhancers. However, this approach is not suitable to track multiple cell populations, as it may lead to confounding results in case the contrast agent is released from the labeled cells. This paper demonstrates how the use of CEST agents can overcome these issues. After encapsulating paramagnetic lanthanide shift reagents, we may shift the absorption frequency of the intracellular water resonance (δIn), thus generating frequency‐encoding CEST responsive cells that can be visualized in the MR image by applying the proper RF irradiation.

Methods

Eu‐HPDO3A, Dy‐HPDO3A, and Tm‐HPDO3A were used as shift reagents for labeling murine breast cancer cells and murine macrophages by hypotonic swelling and pinocytosis. The CEST‐MR images were acquired at 7 T, and the saturation transfer effect was measured. Samples at different dilution of cells were analyzed to quantify the detection threshold. In vitro experiments of cell proliferation were carried out. Finally, murine breast cancer cells were injected subcutaneously in mice, and MR images were acquired to assess the proliferation index in vivo.

Results

It was found that entrapment of the paramagnetic complexes into endosomes (i.e., using the pinocytosis route) leads to an enhanced shift of the intracellular water resonance. δIn appears to be proportional to the effective magnetic moment (μeff) and to the concentration of the loaded lanthanide complex. Moreover, a higher shift is present when the complexes are entrapped in the endosomes. The cell proliferation index was assessed both in vitro and in vivo by evaluating the reduction of δIn value in the days after the cell labeling.

Conclusion

Cells can be visualized by CEST MRI after loading with paramagnetic shift reagent, by exploiting the large ensemble of the properly shifted intracellular water molecules. A better performance is obtained when the complexes are entrapped inside the endosomes. The observed (δIn) value is strongly correlated to the chemical nature of the probe, and to its concentration and cellular localization. Two applications of this method are reported in this paper: (1) for in vivo cell visualization and (2) for the monitoring of the cellular proliferation process, as this method is accompanied by a change in δIn that may be exploited as a longitudinal reporter of the proliferation rate.
Hybrid hyper‐reduced modeling for contact mechanics problems
Authors: Fauque J. , Ramière I. , Ryckelynck D.
Published: March 2018

The model reduction of mechanical problems involving contact remains an important issue in computational solid mechanics. In this article, we propose an extension of the hyper‐reduction method based on a reduced integration domain to frictionless contact problems written by a mixed formulation. As the potential contact zone is naturally reduced through the reduced mesh involved in hyper‐reduced equations, the dual reduced basis is chosen as the restriction of the dual full‐order model basis. We then obtain a hybrid hyper‐reduced model combining empirical modes for primal variables with finite element approximation for dual variables. If necessary, the inf‐sup condition of this hybrid saddle‐point problem can be enforced by extending the hybrid approximation to the primal variables. This leads to a hybrid hyper‐reduced/full‐order model strategy. This way, a better approximation on the potential contact zone is further obtained. A posttreatment dedicated to the reconstruction of the contact forces on the whole domain is introduced. In order to optimize the offline construction of the primal reduced basis, an efficient error indicator is coupled to a greedy sampling algorithm. The proposed hybrid hyper‐reduction strategy is successfully applied to a 1‐dimensional static obstacle problem with a 2‐dimensional parameter space and to a 3‐dimensional contact problem between two linearly elastic bodies. The numerical results show the efficiency of the reduction technique, especially the good approximation of the contact forces compared with other methods.
Manufacturing Nanoparticles with Orthogonally Adjustable Dispersibility in Hydrocarbons, Fluorocarbons, and Water
Authors: Zeininger Lukas , Stiegler Lisa M. S. , Portilla Luis , Halik Marcus , Hirsch Andreas
Published: March 2018

Invited for this month's cover picture is the group of Prof. Dr. Andreas Hirsch from Friedrich Alexander University (Germany). The cover picture shows shell‐by‐shell coated nanoparticle ‘chameleons’—wet‐chemically surface‐modified nanoparticles that can reversibly adjust their dispersibility to entirely orthogonal solvent environments. Read the full text of their Full Paper at 10.1002/open.201800011.
Effects of low contents of A2M3O12 submicronic thermomiotic‐like fillers on thermal expansion and mechanical properties of HDPE‐based composites
Authors: Pontón Patricia I. , Prisco Luciana P. , Marinkovic Bojan A.
Published: March 2018

In this work, pristine Al2W3O12 and Y2W3O12 submicronic fillers, belonging to A2M3O12 family of thermomiotic materials, were incorporated into a high density polyethylene matrix (HDPE) in low contents (from 0.1 to 1.1 vol.%) to study the influence thereof on the coefficient of thermal expansion (CTE) and mechanical properties of the as‐prepared composites. The CTE of HDPE and HDPE/A2M3O12 composites is affected by the first heating cycle, but it remained unchanged after the second heating run. Both Y2W3O12 and Al2W3O12 fillers decrease the CTE of composites. However, Y2W3O12 acts more efficiently than Al2W3O12 to decrease this property and caused a CTE reduction in the range of 20–25% for the temperature interval between 25 and 70°C during the second heating cycle. The filler content does not have a strong influence on CTE for both types of composites, considering the standard deviations. The thermal stability of HDPE is not affected by the addition of fillers. However, the fillers significantly increase the degree of crystallinity, especially in the case of Y2W3O12. For the highest filler content (1.1 vol.%), the Young's modulus of composites increased up to 21 and 32% in the case of Al2W3O12 and Y2W3O12, respectively. POLYM. COMPOS., 39:E1821–E1833, 2018. © 2018 Society of Plastics Engineers
Utilization of drugs with pregnancy exposure registries during pregnancy
Authors: Illoh Onyekachukwu A. , Toh Sengwee , Andrade Susan E. , Hampp Christian , Sahin Leyla , Gelperin Kate , Taylor Lockwood , Bird Steven T.
Published: March 2018

Purpose

To describe the utilization of drugs with pregnancy exposure registries by trimester during pregnancy, in comparison with matched nonpregnant episodes and a pre‐pregnancy period.

Methods

We identified live‐born deliveries from women aged 10 to 54 years and matched the pregnancies 1:1 with nonpregnant episodes from a comparator cohort not delivering live‐born infants, using data from 2001 to 2013 in the Sentinel Distributed Database. We evaluated the utilization of 34 drugs with pregnancy exposure registries, comparing utilization during pregnancy to the matched nonpregnant episodes, and to the 90 days before pregnancy.

Results

We identified 1 895 597 pregnancies ending in live births in 1 598 697 women and 1 895 597 matched nonpregnant episodes in 1 582 581 women. We observed a lower prevalence of use for most drugs during pregnancy compared with the matched nonpregnant episodes, and the 90‐day pre‐pregnancy period. The median (interquartile range) prevalence ratio of use, at any time during pregnancy, for all products was 0.2 (0.1‐0.3) comparing pregnant to nonpregnant episodes. Overall, there was a decrease in drug utilization by trimester; from 2.6% in the 90 days preceding pregnancy to 2.1% in the first trimester, 1.1% in the second trimester, and 0.9% in the third trimester.

Conclusions

Among drugs with pregnancy exposure registries, use was less during pregnancy compared with before pregnancy and to the matched nonpregnant episodes. The lower utilization during pregnancy suggests that women may be avoiding these drugs to minimize potentially harmful exposure during pregnancy. This lower utilization may increase the challenges of further studying the safety of these drugs using pregnancy exposure registries.
Salt concentration dependence of the mechanical properties of LiPF6/poly(propylene glycol) acrylate electrolyte at a graphitic carbon interface: A reactive molecular dynamics study
Authors: Verners Osvalds , Lyulin Alexey V. , Simone Angelo
Published: March 2018

This reactive molecular dynamics study explores the salt concentration dependence of the viscoelastic and mechanical failure properties of a poly(propylene glycol)/LiPF6‐based solid polymer electrolyte (SPE) at a graphitic carbon electrode interface. To account for the finite‐size effect of interface‐confined SPE films, the properties of two distinct film thicknesses are compared with the respective bulk properties. Additionally, the effect of uniaxial compression in the interface‐normal direction on free energy profiles of Li‐ion SPE‐desolvation is studied. © 2018 The Authors. Journal of Polymer Science Part B: Polymer Physics Published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 718–730
Isolation and identification of floral attractants from a nectar plant for the dried bean beetle, Acanthoscelides obtectus (Coleoptera: Chrysomelidae, Bruchinae)
Authors: Vuts József , Woodcock Christine M , Caulfield John C , Powers Stephen J , Pickett John A , Birkett Michael A
Published: March 2018

BACKGROUND

The response of virgin females of the legume pest Acanthoscelides obtectus (Coleoptera: Bruchidae) to headspace extracts of volatiles collected from flowers of a nectar plant, Daucus carota, was investigated using behaviour (four‐arm olfactometry) and coupled gas chromatography–electroantennography (GC‐EAG).

RESULTS

Odours from inflorescences were significantly more attractive to virgin female beetles than clean air. Similarly, a sample of volatile organic compounds (VOCs) collected by air entrainment (dynamic headspace collection) was more attractive to beetles than a solvent control. In coupled GC‐EAG experiments with beetle antennae and the VOC extract, six components showed EAG activity. Using coupled GC–mass spectrometry (GC–MS) and GC peak enhancement with authentic standards, the components were identified as α‐pinene (S:R 16:1), sabinene, myrcene, limonene (S:R 1:3), terpinolene and (S)‐bornyl acetate. Females preferred the synthetic blend of D. carota EAG‐active volatiles to the solvent control in bioassays. When compared directly, odours of D. carota inflorescences elicited stronger positive behaviour than the synthetic blend.

CONCLUSION

This is the first report of behaviourally active volatiles linked to pollen location for A. obtectus, and development of the six‐component blend is being pursued, which could underpin the design of semiochemical‐based field management approaches against this major pest of stored products. © 2018 Society of Chemical Industry
Design, Properties, and TFT Application of Solution‐Processed In‐Ga‐Cd‐O Thin Films
Authors: Song Anran , Javaid Kashif , Liang Yu , Wu Weihua , Yu Jingjing , Liang Lingyan , Zhang Hongliang , Lan Linfeng , Chang Ting‐Chang , Cao Hongtao
Published: March 2018

Concerning the revolutionary future of electronic devices, high‐performance solution‐processable semiconductors have earned increasing academic and industrial research interests. In this paper, we synthesize In‐Ga‐Cd‐O semiconductor thin films via a solution method. Transparent amorphous/nanocrystalline oxide thin films with small surface roughness have been grown by controlling the relative ratio of Cd‐content. The present thin‐film transistor with an optimized Cd‐ratio exhibits a saturation field‐effect mobility up to 10 cm2 V−1 s−1, an on/off current ratio of ≈1.3 × 109, and a threshold voltage shift of ≈2.6 V under −5 V gate bias of 10 000 s, which are superior or comparable to those reported values of solution‐processed conventional In‐Ga‐Zn‐O counterparts. Our results indicate that the proposed In‐Ga‐Cd‐O semiconductor would endow a promising transparent amorphous/nanocrystalline active material for electronic devices.
Maslinic acid induces autophagy by down‐regulating HSPA8 in pancreatic cancer cells
Authors: Tian Ye , Xu Huanli , Farooq Ammad Ahmad , Nie Baozeng , Chen Xiaoliang , Su Shuonan , Yuan Ru , Qiao Gan , Li Cong , Li Xiao , Liu Xiaohui , Lin Xiukun
Published: March 2018

Maslinic acid (MA), a natural pentacyclictriterpene, displays cytotoxic activity on various types of cancer cells. However, its underlying mechanism is unclear. In this study, we assessed the effect of MA on autophagy of human pancreatic cancer cells, and the potential autophagic pathway was presented. MA inhibited the proliferation and induced autophagy of Panc‐28 cells by altering the expressions of autophagy related proteins. SDS‐PAGE analysis revealed that one protein band was significantly down‐regulated in cells treated with MA, and the band was identified as heat shock protein HSPA8 as analyzed using Western blot and MS, MS/MS approaches. HSPA8 knockdown could significantly inhibit cell viability and enhance the cytotoxic effects of MA, whereas HSPA8 overexpression was able to enhance cell viability, diminishing the effects of MA. Western blot analysis indicated that the effect of MA on the expression of autophagy related genes was increased significantly in cells treated with HSPA8 inhibitor VER‐155008, whereas HSPA8 inducer geranylgeranylacetone antagonized the effects of MA. Our study provides evidence that MA is able to induce of autophagy via down‐regulation of HSPA8 in Panc‐28 cells.
Adaptive control charts for skew‐normal distribution
Authors: Chiang Jyun‐You , Tsai Tzong‐Ru , Su Nan‐Cheng
Published: March 2018

The standard Shewhart‐type
chart, named FSS‐
chart, has been widely used to detect the mean shift of process by implementing fixed sample and sampling frequency schemes. The FSS‐
chart could be sensitive to the normality assumption and is inefficient to catch small or moderate shifts in the process mean. To monitor nonnormally distributed variables, Li et al [Commun Stat‐Theory Meth. 2014; 43(23):4908‐4924] extended the study of Tsai [Int J Reliab Qual Saf Eng. 2007; 14(1):49‐63] to provide a new skew‐normal FSS‐
(SN FSS‐
) chart with exact control limits for the SN distribution. To enhance the sensitivity of the SN FSS‐
chart on detecting small or moderate mean shifts in the process, adaptive
charts with variable sampling interval (VSI), variable sample size (VSS), and variable sample size and sampling interval (VSSI) are introduced for the SN distribution in this study. The proposed adaptive control charts include the normality adaptive charts as special cases. Simulation results show that all the proposed SN VSI‐
, SN VSS‐
, and SN VSSI‐
charts outperform the SN FSS‐
chart on detecting small or moderate shifts in the process mean. The impact of model misspecification on using the proposed adaptive charts and the sample size impact for using the FSS‐
chart to monitor the mean of SN data are also discussed. An example about single hue value in polarizer manufacturing process is used to illustrate the applications of the proposed adaptive charts.
Development on a magnetic anchoring robot system based on visual servo control for laparoendoscopic single‐site surgery
Authors: Feng Haibo , Lu Yu , Chen Dong , Ma Tengfei , Fu Yili
Published: March 2018

Background

Surgical robot systems have been used in laparoendoscopic single‐site surgery (LESS) to improve patient outcomes. A magnetic anchoring surgical robot system for LESS can effectively extend the operation space.

Methods

A robot system based on visual servo control for LESS is proposed. It includes a magnetic anchoring robot and a control subsystem, in which an uncalibrated visual servo control method obtains an accurate positioning capability of the robot for LESS.

Results

The results of the simulation and the tissue experiment show that the robot system can successfully accomplish the expected control functionalities for LESS. The average positioning error of the proposed system is 1.622 mm.

Conclusion

The magnetic anchoring robot system is able to implement the autonomous positioning of its end‐effector through the proposed control approach according to experimental results.
Microdissection testicular sperm extraction in five Japanese patients with non‐mosaic Klinefelter's syndrome
Authors: Chihara Makoto , Ogi Kanna , Ishiguro Tatsuya , Yoshida Kunihiko , Godo Chikako , Takakuwa Koichi , Enomoto Takayuki
Published: March 2018

Cases

Microdissection testicular sperm extraction (micro‐TESE) was performed on five Japanese men with non‐mosaic Klinefelter's syndrome (KS) and non‐obstructive azoospermia in the authors' department. Here is reported the operative results and partner's clinical course for two cases where spermatozoa could be acquired. Also encountered was a man with non‐mosaic KS with the partial deletion of azoospermia factor (AZF)b. Because this is rare, it is reported in detail in the context of the previous literature. This case series describes the first experience of micro‐TESE by gynecologists in the current department.

Outcome

The egg collection date was adjusted to the micro‐TESE day by using the modified ultra‐long method. Intracytoplasmic sperm injection (ICSI) was implemented for two men whose spermatozoa were acquired by micro‐TESE, with these progressing to the blastocyst stage. Subsequently, one case conceived after the transfer of fresh embryos and a healthy baby was delivered. However, spermatozoa could not be retrieved from the man with non‐mosaic KS who was harboring the partial deletion of AZFb.

Conclusion

These findings suggest that ovulation induction by using the modified ultra‐long method with micro‐TESE and ICSI on the same day represents an effective treatment option for men with non‐mosaic KS. As there are cases where AZF deletion is recognized among patients with non‐mosaic KS, screening before micro‐TESE is strongly recommended.
Robust exponential stability of uncertain stochastic systems with probabilistic time‐varying delays
Authors: Hu Zhipei , Deng Feiqi , Shi Peng , Luo Shixian , Xing Mali
Published: March 2018

This paper is concerned with the problem of delay‐distribution–dependent robust exponential stability for uncertain stochastic systems with probabilistic time‐varying delays. Firstly, inspired by a class of networked systems with quantization and packet losses, we study the stabilization problem for a class of network‐based uncertain stochastic systems with probabilistic time‐varying delays. Secondly, an equivalent model of the resulting closed‐loop network‐based uncertain stochastic system is constructed. Different from the previous works, the proposed equivalent system model enables the controller design of the network‐based uncertain stochastic systems to enjoy the advantage of probability distribution characteristic of packet losses. Thirdly, by applying the Lyapunov‐Krasovskii functional approach and the stochastic stability theory, delay‐distribution–dependent robust exponential mean‐square stability criteria are derived, and the sufficient conditions for the design of the delay‐distribution–dependent controller are then proposed to guarantee the stability of the resulting system. Finally, a case study is given to show the effectiveness of the results derived. Moreover, the allowable upper bound of consecutive packet losses will be larger in the case that the probability distribution characteristic of packet losses is taken into consideration.
Catalytically Active Bacterial Nanocellulose‐Based Ultrafiltration Membrane
Authors: Xu Ting , Jiang Qisheng , Ghim Deoukchen , Liu Keng‐Ku , Sun Hongcheng , Derami Hamed Gholami , Wang Zheyu , Tadepalli Sirimuvva , Jun Young‐Shin , Zhang Qinghua , Singamaneni Srikanth
Published: March 2018

Large quantities of highly toxic organic dyes in industrial wastewater is a persistent challenge in wastewater treatment processes. Here, for highly efficient wastewater treatment, a novel membrane based on bacterial nanocellulose (BNC) loaded with graphene oxide (GO) and palladium (Pd) nanoparticles is demonstrated. This Pd/GO/BNC membrane is realized through the in situ incorporation of GO flakes into BNC matrix during its growth followed by the in situ formation of palladium nanoparticles. The Pd/GO/BNC membrane exhibits highly efficient methylene orange (MO) degradation during filtration (up to 99.3% over a wide range of MO concentrations, pH, and multiple cycles of reuse). Multiple contaminants (a cocktail of 4‐nitrophenol, methylene blue, and rhodamine 6G) can also be effectively treated by Pd/GO/BNC membrane simultaneously during filtration. Furthermore, the Pd/GO/BNC membrane demonstrates stable flux (33.1 L m−2 h−1) under 58 psi over long duration. The novel and robust membrane demonstrated here is highly scalable and holds a great promise for wastewater treatment.
New 2D Carbon Nitride Organic Materials Synthesis with Huge‐Application Prospects in CN Photocatalyst
Authors: Zhao Gang , Cheng Yanling , Wu Yongzhong , Xu Xijin , Hao Xiaopeng
Published: March 2018

In recent years, 2D materials are attracting increased attention because of their excellent properties. In this paper, new 2D carbon nitride (CN) organic materials are successfully prepared on the basis of the organic synthesis theory, and the thickness is about 1.5 nm. This new 2D CN organic material further strengthens the 2D materials family. Meanwhile, their synthetic mechanism is theoretically speculated. Then CN photocatalysts of several structures are obtained by roasting 2D CN organic materials. Through the photocatalytic hydrogen production experiments, the results exhibit that these kinds of photocatalysts have good photocatalytic effects compared to common g‐C3N4.
In‐syringe vortex‐assisted emulsification microextraction with solidified floating organic drop for the separation of aflatoxins from feed before their determination by HPLC
Authors: Asadi Mohammad
Published: March 2018

A simple and rapid in‐syringe vortex‐assisted emulsification microextraction with solidified floating organic drop was developed for the extraction of aflatoxins (B1 and B2) from feed before their determined by high‐performance liquid chromatography. Several experimental factors affect the microextraction efficiency such as sample pH, vortex time, type of extraction solvent, and sample volume that have been evaluated and optimized. The calibration curves were linear in the range of 50.0–500.0 and 40.0–400.0 ng kg−1 for aflatoxin B1 and aflatoxin B2, respectively. The limits of detection were found to be 16.0 and 12.0 ng kg−1 for aflatoxin B1 and aflatoxin B2, respectively. The inter‐day and intra‐day precisions of the developed method were in the range of 5.3–9.3%. Finally, the developed microextraction method was successfully used in the extraction and quantification of aflatoxins in several feed samples.
Prior Treatment with Anti-High Mobility Group Box-1 Antibody Boosts Human Neural Stem Cell Transplantation-Mediated Functional Recovery After Spinal Cord Injury
Authors: Uezono Naohiro , Zhu Yicheng , Fujimoto Yusuke , Yasui Tetsuro , Matsuda Taito , Nakajo Masahide , Abematsu Masahiko , Setoguchi Takao , Mori Shuji , Takahashi Hideo K. , Komiya Setsuro , Nishibori Masahiro , Nakashima Kinichi
Published: March 2018

Together with residual host neurons, transplanted neural stem cell (NSC)-derived neurons play a critical role in reconstructing disrupted neural circuits after spinal cord injury (SCI). Since a large number of tracts are disrupted and the majority of host neurons die around the lesion site as the damage spreads, minimizing this spreading and preserving the lesion site are important for attaining further improvements in reconstruction. High mobility group box-1 (HMGB1) is a damage-associated molecular pattern protein that triggers sterile inflammation after tissue injury. In the ischemic and injured brain, neutralization of HMGB1 with a specific antibody reportedly stabilizes the blood-brain barrier, suppresses inflammatory cytokine expression, and improves functional recovery. Using a SCI model mouse, we here developed a combinatorial treatment for SCI: administering anti-HMGB1 antibody prior to transplantation of NSCs derived from human induced pluripotent stem cells (hiPSC-NSCs) yielded a dramatic improvement in locomotion recovery after SCI. Even anti-HMGB1 antibody treatment alone alleviated blood-spinal cord barrier disruption and edema formation, and increased the number of neurites from spared axons and the survival of host neurons, resulting in functional recovery. However, this recovery was greatly enhanced by the subsequent hiPSC-NSC transplantation, reaching an extent that has never before been reported. We also found that this improved recovery was directly associated with connections established between surviving host neurons and transplant-derived neurons. Taken together, our results highlight combinatorial treatment with anti-HMGB1 antibody and hiPSC-NSC transplantation as a promising novel therapy for SCI.
Interactions between Biological Cells and Layered Double Hydroxides: Towards Functional Materials
Authors: Forano Claude , Bruna Felipe , Mousty Christine , Prevot Vanessa
Published: March 2018

This review highlights the current research on the interactions between biological cells and Layered Double Hydroxides (LDH). The as‐prepared biohybrid materials appear extremely attractive in diverse fields of application relating to health care, environment and energy production. We describe how thanks to the main features of biological cells and LDH layers, various strategies of assemblies can be carried out for constructing smart biofunctional materials. The interactions between the two components are described with a peculiar attention to the adsorption, biocompatibilization, LDH layer internalization, antifouling and antimicrobial properties. The most significant achievements including authors′ results, involving biological cells and LDH assemblies in waste water treatment, bioremediation and bioenergy generation are specifically addressed.
Using a three‐dimensional thinking graph to support inquiry learning
Authors: Chen Juanjuan , Wang Minhong , Grotzer Tina A. , Dede Chris
Published: March 2018

The use of external representations has a potential to facilitate inquiry learning, especially in hypothesis generation and scientific reasoning, which are typical difficulties encountered by students. This study proposes and investigates the effects of a three‐dimensional thinking graph (3DTG) that allows learners to combine in a single image, problem information, subject knowledge (key concepts and their relationships), and the hypothesizing and reasoning process involved in exploring a problem, to support inquiry learning. Two classes of eleventh grade students (97 in total) were randomly assigned to use either the 3DTG (i.e., experimental condition) or concept map (i.e., control condition) to complete a group‐based inquiry task in an online environment. Data were collected from multiple data sources, including measures of group inquiry task performance, postknowledge scores, postquestionnaires of student perceptions of consensus building, and open‐ended survey. The analysis of group task performance revealed that participants in the experimental condition performed better in the inquiry task than their counterparts specifically in generating hypotheses and reasoning with data, but not in drawing conclusions. The findings show the 3DTG's benefits in facilitating exploring and justifying hypotheses, and also suggest that the 3DTG can share equal value with concept mapping in terms of drawing conclusions and consensus building. In addition, students using the 3DTG achieved higher scores in the postknowledge test, although no difference was found in their perceptions of consensus building. These findings were validated by students' responses to the survey. Implications of this study and future work are also discussed.
Home blood‐pressure monitoring in a hypertensive pregnant population: cost‐minimization study
Authors: Xydopoulos G. , Perry H. , Sheehan E. , Thilaganathan B. , Fordham R. , Khalil A.
Published: March 2018

Objective

Traditional blood‐pressure monitoring in hypertensive pregnant women requires frequent visits to the maternity outpatient services. Home blood‐pressure monitoring (HBPM) could offer a cost‐saving alternative that is acceptable to patients. The aim of this study was to undertake a health economic analysis of HBPM compared with traditional monitoring in hypertensive pregnant women.

Methods

This was a cost‐minimization study of hypertensive pregnant women who had HBPM with or without the adjunct of a smartphone application (App), via a specially designed pathway, and a control group managed according to the local protocol of regular hospital visits for blood‐pressure monitoring. Outcome measures were the number of outpatient visits, inpatient bed stays and investigations performed. Maternal, fetal and neonatal adverse outcomes were also recorded. Health economic analysis was performed using direct cost comparison of the study dataset and process scenario modeling.

Results

The HBPM group included 108 women, of whom 29 recorded their results on the smartphone App and 79 in their notes. The control group comprised 58 patients. There were significantly more women with chronic hypertension in the HBPM group than in the control group (49.1% vs 25.9%, P = 0.004). The HBPM group had significantly longer duration of monitoring (9 weeks vs 5 weeks, P = 0.004) and started monitoring at an earlier gestational age (30.0 weeks vs 33.6 weeks, P = 0.001) compared with the control group. Despite these differences, the mean saving per week for each patient using HBPM compared with traditional monitoring was £200.69, while for each HBPM patient using the smartphone App, the weekly saving was £286.53 compared with the control group. The process modeling method predicted weekly savings of between £98.32 and £245.80 per patient using HBPM compared with traditional monitoring.

Conclusion

HBPM in hypertensive pregnancy appears to be cost saving compared with traditional monitoring, without compromising maternal, fetal or neonatal safety. Larger studies are required to confirm these findings. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Evaluating autonomous acoustic surveying techniques for rails in tidal marshes
Authors: Stiffler Lydia L. , Anderson James T. , Katzner Todd E.
Published: March 2018

There is a growing interest toward the use of autonomous recording units (ARUs) for acoustic surveying of secretive marsh bird populations. However, there is little information on how ARUs compare to human surveyors or how best to use ARU data that can be collected continuously throughout the day. We used ARUs to conduct 2 acoustic surveys for king (Rallus elegans) and clapper rails (R. crepitans) within a tidal marsh complex along the Pamunkey River, Virginia, USA, during May–July 2015. To determine the effectiveness of an ARU in replacing human personnel, we compared results of callback point‐count surveys with concurrent acoustic recordings and calculated estimates of detection probability for both rail species combined. The success of ARUs at detecting rails that human observers recorded decreased with distance (P ≤ 0.001), such that at <25 m, 90.3% of human‐recorded rails also were detected by the ARU, but at >75 m, only 34.0% of human‐detected rails were detected by the ARU. To determine a subsampling scheme for continuous ARU data that allows for effective surveying of presence and call rates of rails, we used ARUs to conduct 15 continuous 48‐hr passive surveys, generating 720 hr of recordings. We established 5 subsampling periods of 5, 10, 15, 30, and 45 min to evaluate ARU‐based presence and vocalization detections of rails compared with each of the full 60‐min sampling of ARU‐based detection of rails. All subsampling periods resulted in different (P ≤ 0.001) detection rates and unstandardized vocalization rates compared with the hourly sampling period. However, standardized vocalization counts from the 30‐min subsampling period were not different from vocalization counts of the full hourly sampling period. When surveying rail species in estuarine environments, species‐, habitat‐, and ARU‐specific limitations to ARU sampling should be considered when making inferences about abundances and distributions from ARU data. © 2018 The Wildlife Society.
Non-conformal holographic Gauss-Bonnet hydrodynamics
Authors: Buchel Alex
Published: March 2018

Abstract

We study hydrodynamics of four-dimensional non-conformal holographic plasma with non-equal central charges c ≠ a at the ultraviolet fixed point. We compute equation of state, the speed of sound waves, transport coefficients (shear and bulk viscosities), and discuss causality. We study the asymptotic character of the hydrodynamic series for the homogeneous and isotropic expansion of the plasma. We perform computations for finite c − a ≠ 0, but to leading nonvanishing order in the conformal symmetry breaking coupling.
Decrease of cocaine, but not heroin, self-administration and relapse by the tyrosine kinase inhibitor masitinib in male Sprague Dawley rats
Authors: Belin-Rauscent A. , Lacoste J. , Hermine O. , Moussy A. , Everitt B. J. , Belin David
Published: March 2018

Rationale

Accumulating evidence shows that cocaine, and also heroin, influence several tyrosine kinases, expressed in neurons and in non-neuronal populations such as microglia, astrocytes and mast-cells. Drug-induced activation of mast cells both triggers inflammatory processes in the brain mediated by the glial cells they activate, and facilitates histamine release which may directly influence the dopamine system. Thus, by triggering the activation and degranulation of mast cells dependent on the tyrosine kinase c-kit and Fyn, the latter being also involved in NMDA-dependent synaptic plasticity, cocaine and heroin may indirectly influence the neural mechanisms that mediate their reinforcing properties. Masitinib, a novel tyrosine kinase inhibitor with high selectivity for c-Kit, Fyn and Lyn, may alter the aberrant consequences of the activation of these tyrosine kinases by cocaine and heroin.

Objective

We investigated in rats the effect of a chronic oral treatment with masitinib (20 mg/kg) on the reinforcing and motivational properties of self-administered cocaine (250 μg/infusion) and heroin (40 μg/infusion).

Methods

Three different cohorts of rats were trained instrumentally to respond for cocaine, heroin or food under continuous reinforcement. In each group, we assessed the influence of chronic daily treatment with masitinib on the maintenance of instrumental responding and intake and the motivation for the reinforcer. Thus, masitinib and vehicle-treated rats were challenged to adapt to high behavioural demand, to respond under a progressive ratio schedule of reinforcement and to reinstate instrumental responding after extinction and/or abstinence.

Results

Masitinib selectively decreased cocaine intake, the motivation for cocaine and the subsequent propensity to respond for cocaine under extinction, while having no effect on instrumental responding for heroin or food.

Conclusion

The present findings suggest masitinib, a drug with proven efficacy in CNS disorders, could represent a novel treatment for cocaine addiction provided its influence on the reinforcing and incentive properties of the drug is confirmed.