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Objective To examine the role of driving time to cancer care facilities on days to cancer treatment initiation and cause-specific survival for cervical cancer patients. Methods A retrospective cohort analysis of patients diagnosed with invasive cervical cancer during 2001–2016, using South Carolina Central Cancer Registry data linked to vital records. Kaplan-Meier survival curves and Cox proportional hazards models were used to examine the association of driving times to both a patient's nearest and actual cancer treatment initiation facility with cause-specific survival and time to treatment initiation. Results Of 2518 eligible patients, median cause-specific survival was 49 months (interquartile, 17–116) and time to cancer treatment initiation was 21 days (interquartile, 0–40). Compared to patients living within 15 min of the nearest cancer provider, those living more than 30 min away were less likely to receive initial treatment at teaching hospitals, Joint Commission accredited facilities, and/or Commission on Cancer accredited facilities. After controlling for patient, clinical, and provider characteristics, no significant associations existed between driving times to the nearest cancer provider and survival/time to treatment. When examining driving times to treatment initiation (rather than simply nearest) provider, patients who traveled farther than 30 min to their actual providers had delayed initiation of cancer treatment (hazard ratio, 0.81; 95% confidence interval, 0.73–0.90), including surgery (0.82; 95% CI, 0.72–0.92) and radiotherapy (0.82, 95% CI, 0.72–0.94). Traveling farther than 30 min to the first treating provider was not associated with worse cause-specific survival. Conclusions For cervical cancer patients, driving time to chosen treatment providers, but not to the nearest cancer care provider, was associated with prolonged time to treatment initiation. Neither was associated with survival.

Diabetic retinopathy (DR) as a retinal neovascularization‐related disease is one of the leading causes of irreversible blindness in patients. The goal of this study is to determine the role of a G‐protein‐coupled chemoattractant receptor (GPCR) FPR2 (mouse Fpr2) in the progression of DR, in order to identify novel therapeutic targets. We report that Fpr2 was markedly upregulated in mouse diabetic retinas, especially in retinal vascular endothelial cells, in associated with increased number of activated microglia and Müller glial cells. In contrast, in the retina of diabetic Fpr2 −/− mice, the activation of vascular endothelial cells and glia was attenuated with reduced production of proinflammatory cytokines. Fpr2 deficiency also prevented the formation of acellular capillary during diabetic progression. Furthermore, in oxygen‐induced retinopathy (OIR) mice, the absence of Fpr2 was associated with diminished neovasculature formation and pathological vaso‐obliteration region in the retina. These results highlight the importance of Fpr2 in exacerbating the progression of neuroglial degeneration and angiogenesis in DR and its potential as a therapeutic target.

Due to the lack of color, the strong speckle noise, and the complex background clutter, target detection in synthetic aperture radar (SAR) images is a challengeable task. A novel saliency and background prior (SBP)-based residential area detection method for SAR images is proposed in this letter. It has three major advantages compared with other methods: 1) in saliency analysis, it deeply exploits the image feature and conceives a new texture representation using the amplitude of partitioning Fourier transform (pFT), which compensates for the lack of color and spectrum information in SAR; 2) it employs the superpixel-level background prior and monitors the average intensity level (AIL) of each superpixel for generating accurate outlines of residential areas; and 3) two regional feature-based indices are presented to select the background clutter, and the results serve as a modification to saliency analysis. Experiments using ALOS PALSAR images show that the proposed method has great priority in both quality and quantity over competing methods by extracting integrated residential areas with clear boundaries.

Background: In Alzheimer’s disease (AD), activation of astrocyte participates in the development of neurodegenerative diseases through neuroinflammation and disturbs glia-neuron interaction. Cancerous Inhibitor of PP2A (CIP2A) is an endogenous PP2A inhibitor. CIP2A upregulation specifically in astrocytes causes reactive astrogliosis, synaptic degeneration and cognitive deficits. However, the underlying mechanism of CIP2A upregulation remains unclear. Methods: In 3xTg-AD mice, we determined ChK1 was activated and related to DNA damage upregulating CIP2A by WB. We transfected EGFP-ChK1 plasmid into HEK293-T cell to determine ChK1 induces CIP2A upregulation and PP2A inhibition. We incubated Aβ and infected GFAP-ChK1-LV into primary astrocytes to confirm the signaling pathway in astrocytes and astrogliosis in AD. GFAP-ChK1-AAV was injected into C57/BL6 mice to induce specific expression of target protein in astrocytes. ChK1 inhibitor (SB) was performed to reverse the ChK1 activity. Outcomes were assessed using molecular (immunofluorescent staining, Western Blot and Golgi staining) measures to estimate symptomatic pathology and behavioral (NORT, OLT, MWM and FCT) measures to assess cognitive function. For most experiments, subjects were randomly assigned to experimental groups, and data were collected under blinded experimental conditions.Results: We demonstrated that DNA damage related Checkpoint kinase 1 (ChK1) was activated in 3xTg-AD mice. ChK1-mediated CIP2A overexpression drove inhibition of PP2A and activated STAT3, then led to reactive astrogliosis and neurodegeneration in vitro. Infection of mouse brain with GFAP-ChK1-AAV induced AD-like cognitive deficits and exacerbated AD pathologies in vivo. In conclusion, we showed that ChK1 activation induced reactive astrogliosis, degeneration of neurons and deterioration of AD through CIP2A-PP2A-STAT3 pathway, and inhibiting ChK1 might be a potential therapeutic approach for AD treatment.Conclusions: These results suggest that ChK1 is upregulated in 3xTg-AD mice, ChK1-mediated CIP2A overexpression drives inhibition of PP2A and activates STAT3, then leads to reactive astrogliosis, neurodegeneration and AD-like cognitive deficits in vitro and in vivo.

In an electroencephalogram- (EEG-) based brain–computer interface (BCI), a subject can directly communicate with an electronic device using his EEG signals in a safe and convenient way. However, the sensitivity to noise/artifact and the non-stationarity of EEG signals result in high inter-subject/session variability. Therefore, each subject usually spends long and tedious calibration time in building a subject-specific classifier. To solve this problem, we review existing signal processing approaches, including transfer learning (TL), semi-supervised learning (SSL), and a combination of TL and SSL. Cross-subject TL can transfer amounts of labeled samples from different source subjects for the target subject. Moreover, Cross-session/task/device TL can reduce the calibration time of the subject for the target session, task, or device by importing the labeled samples from the source sessions, tasks, or devices. SSL simultaneously utilizes the labeled and unlabeled samples from the target subject. The combination of TL and SSL can take advantage of each other. For each kind of signal processing approaches, we introduce their concepts and representative methods. The experimental results show that TL, SSL, and their combination can obtain good classification performance by effectively utilizing the samples available. In the end, we draw a conclusion and point to research directions in the future.

Topical isotretinoin is commonly used to treat acne. However, topical isotretinoin has side effects and can hardly permeate through the stratum corneum, the most important skin barrier. Therefore, this study aimed to demonstrate the efficacy of nanoparticles as stable carriers with great curative effects, low side effects, and strong transdermal ability.In a rabbit model of hyperkeratinization, STCM-ATRA-NPs showed significant therapeutic efficacy. By contrast, negative therapeutic efficacy was observed in a golden hamster model of hyper sebum production. Scanning electron microscopy and Fourier transform infrared spectral analyses showed that nanoparticles could penetrate the stratum corneum. Western blotting demonstrated that the nanoparticles could enhance the transdermal efficacy of isotretinoin by reducing the effect of keratin and tight junction proteins. Further, nanoparticles enhanced endocytosis, thereby promoting drug penetration and absorption into the skin.STCM-ATRA-NPs were demonstrated to control isotretinoin release, reducing its side effects, and efficiently permeating through the skin by reducing the effect of keratin and tight junction proteins and enhancing endocytosis.

A novel saliency-driven oil tank detection method based on multidimensional feature vector clustering (MFVC) is proposed in this letter for synthetic aperture radar (SAR) images. There are three major contributions: 1) a specially designed MFVC method, which is suitable for SAR images without true colors, is employed to detect oil tanks roughly by saliency analysis. Five important complementary features, including intensity, texture, structure, and 2-D coordinates, form a 5-D vector, and then an unsupervised strategy is employed for clustering the 5-D feature vectors to acquire the saliency map; 2) For accurate location, the shape limit coefficient is added to the original active contour model to extract contours of top surfaces; and 3) according to the relations of top, bottom, and the brightest arch, bottoms of oil tanks are computed precisely. Experiments are conducted in two aspects: evaluation for saliency analysis, and for bottom location. Results show that the MFVC method outperforms competing methods in maintaining complete oil tanks and accurate boundaries, and removing the background clutter as much as possible.

This paper presents an open-source simulation platform developed for implementation of both homogeneous and heterogeneous robotic swarm scenarios. BeeGround is a fully modular simulation software that allows for a variety of experimental setups with different robotic platforms and population sizes. Users are able to define environmental conditions, e.g. size, various properties like temperature and humidity, and obstacles arrangements. The swarm controller, the individual's behaviour, is defined with a separate programming script. In this paper, we simulated honeybees aggregation mechanism as a case study to investigate the feasibility of the developed simulation platform. The results demonstrated that the developed platform is a reliable simulation software for implementing multi-agent and swarm robotics scenarios with very large population sizes, e.g. 1000 robots.

Swarm robotics is mainly inspired by the collective behaviour of social animals in nature. Among different behaviours such as foraging and flocking performed by social animals; aggregation behaviour is often considered as the most basic and fundamental one. Aggregation behaviour has been studied in different domains for over a decade. In most of these studies, the settings are over-simplified that are quite far from reality. In this paper, we investigate cue-based aggregation behaviour using BEECLUST in a complex environment having two cues –one being the local optimum and the other being the global optimum– with an obstacle between the two cues. The robotic validation of the BEECLUST strategy in a complex environment is the main motivation of this paper. We measured the aggregation size on both cues with and without the obstacle varying the number of robots. The simulations were performed on a custom open-source simulation platform, Bee-Ground, using MONA robots. The results showed that the aggregation behaviour with BEECLUST strategy was able to overcome a certain degree of environmental complexities revealing the robustness of the method. We also verified these results using our stock-flow model.

Human-Object Interaction (HOI) detection lies at the core of action understanding. Besides 2D information such as human/object appearance and locations, 3D pose is also usually utilized in HOI learning since its view-independence. However, rough 3D body joints just carry sparse body information and are not sufficient to understand complex interactions. Thus, we need detailed 3D body shape to go further. Meanwhile, the interacted object in 3D is also not fully studied in HOI learning. In light of these, we propose a detailed 2D-3D joint representation learning method. First, we utilize the single-view human body capture method to obtain detailed 3D body, face and hand shapes. Next, we estimate the 3D object location and size with reference to the 2D human-object spatial configuration and object category priors. Finally, a joint learning framework and cross-modal consistency tasks are proposed to learn the joint HOI representation. To better evaluate the 2D ambiguity processing capacity of models, we propose a new benchmark named Ambiguous-HOI consisting of hard ambiguous images. Extensive experiments in large-scale HOI benchmark and Ambiguous-HOI show impressive effectiveness of our method. Code and data are available at https://github.com/DirtyHarryLYL/DJ-RN., Accepted to CVPR 2020, supplementary materials included, code available:https://github.com/DirtyHarryLYL/DJ-RN

Existing image-based activity understanding methods mainly adopt direct mapping, i.e. from image to activity concepts, which may encounter performance bottleneck since the huge gap. In light of this, we propose a new path: infer human part states first and then reason out the activities based on part-level semantics. Human Body Part States (PaSta) are fine-grained action semantic tokens, e.g. , which can compose the activities and help us step toward human activity knowledge engine. To fully utilize the power of PaSta, we build a large-scale knowledge base PaStaNet, which contains 7M+ PaSta annotations. And two corresponding models are proposed: first, we design a model named Activity2Vec to extract PaSta features, which aim to be general representations for various activities. Second, we use a PaSta-based Reasoning method to infer activities. Promoted by PaStaNet, our method achieves significant improvements, e.g. 6.4 and 13.9 mAP on full and one-shot sets of HICO in supervised learning, and 3.2 and 4.2 mAP on V-COCO and images-based AVA in transfer learning. Code and data are available at http://hake-mvig.cn/., Comment: Accepted to CVPR 2020, supplementary materials included, code available: http://hake-mvig.cn/

Images degraded by haze usually have low contrast and fide colours, and thus have bad effects on applications such as object tracking, face recognition, and intelligent surveillance. So the purpose of dehazing is to recover the image contrast without colour distortion. The dark channel prior (DCP) is widely used in the field of haze removal because of its simplicity and effectiveness. However, when faced with bright white objects, DCP overestimates the haze from its true value and thus causes colour distortion. In this study, the authors propose a dehazing model combining saliency detection with DCP to obtain recovered images with little colour distortion. There are three main contributions. First, they introduce a novel saliency detection method, focusing on superpixel intensity contrast, to extract bright white objects in the hazy image. Those objects are not used to estimate the atmospheric light and transmission in the dark channel image. Second, a self-adaptive upper bound is set for the scene radiance to prevent some regions being too bright. Third, they propose a quantitative indicator, colour variance distance, to evaluate the colour restoration. Experimental results show that their proposed model generates less colour distortion and has better comprehensive performance than competing models.

The bowtie antenna is a topic of growing interest in recent years. In this paper, we design, fabricate, and characterize a modified gold bowtie antenna integrated on a transparent silica substrate. The bowtie antenna is designed with broad RF bandwidth to cover the X-band in the electromagnetic spectrum. We numerically investigate the antenna characteristics, specifically its resonant frequency and enhancement factor. Our designed bowtie antenna provides a strong broadband electric field enhancement in its feed gap. Taking advantage of the low-k silica substrate, high enhancement factor can be achieved without the unwanted reflection and scattering from the backside silicon handle which is the issue of using an SOI substrate. We simulate the dependence of resonance frequency on bowtie geometry, and verify the simulation results through experimental investigation, by fabricating different sets of bowtie antennas on silica substrates and then measuring their resonance frequencies. In addition, the far-field radiation pattern of the bowtie antenna is measured, and it shows dipole-like characteristics with large beam width. Such a broadband antenna will be useful for a myriad of applications, ranging from photonic electromagnetic wave sensing to wireless communications., Comment: arXiv admin note: substantial text overlap with arXiv:1503.01907

The deformation microstructures of a Mg–Gd–Y–Zr alloy under ballistic impact at a velocity of 400 m·s−1 were characterized using optical microscopy (OM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) techniques. Due to the high strain rate in the test, twinning and double twinning were prevalent in the deformation microstructure; high energy { 10 1 ¯ 3 } compression twins and twin–twin intersections were also readily observed. Adiabatic shear bands, the precursor of cracks, propagated along grain boundaries and through twin-rich zones. Four different lattice rotation conditions were observed in the deformation microstructure. Low angle boundaries generated by dislocations glide and dislocation arrays were partially responsible for the nonuniform orientations of the deformed grains. Some high angle boundaries formed through twinning followed by lattice rotation. Lattice rotation was also observed in unusual tension twins with misorientation angles lower than 86°. Finally, the sectioned region and matrix rotated with small angles during the twin–twin intersection process. These unique twin behaviors and lattice rotations can be attributed to accommodation of severe plastic strain and maintaining compatibility between neighboring microstructures. These deformation behaviors are beneficial for materials to improve the ballistic performance.

Droop control strategy enables the microgrid switch between grid-connected and islanded mode flexibly, and easily realizes the “plug and play” function of distributed generation and loads, which has recently aroused great concerns. However, small disturbances may occur during the changing process and eventually yield transient oscillation, thus the focus of microgrid control is how to switch smoothly within different operation modes. In order to improve the dynamic characteristics of an inverter-based microgrid, this paper derived a precise small-signal state-space model of the whole microgrid including droop controller, network, and loads. The key control parameters of the inverter and their optimum ranges, which greatly influence the damping frequency of oscillatory components in the transient response, can be obtained through eigenvalue analysis. In addition, genetic algorithm is introduced to search for optimal settings of the key parameters during time-domain simulation in MATLAB/Simulink. Simulation results verified the effectiveness of the proposed small-signal dynamic model and optimization algorithm, and enhanced the dynamic performance of the microgrid, which can be the reference for parameter design of droop control in low voltage microgrids.

A silica/electro-optic (EO) polymer phase modulator is proposed for microwave radiation receiver with the use of a bowtie antenna. Waveguide design optimization is presented for a waveguide with an EO polymer core and silica/sol-gel cladding. Electrode effects on the insertion loss and poling efficiency are also analyzed and conditions for low-loss and high poling efficiency established. The bowtie antenna is simulated and shows a broadband response with a maximum at 5 GHz and a 3 dB-bandwidth of approximately 12 GHz. A fiber splicing technique is presented that reduces coupling loss between SMF-28 and the waveguide. Experimental results for a fabricated device with microwave-response between 10–14 GHz are shown with carrier to first sideband intensity difference of up to –36 dB.

We present the design, fabrication and characterization of a compact and highly sensitive integrated photonic electromagnetic field sensor based on a silicon-organic hybrid modulator driven by a bowtie antenna. Slow-light effects in the electro-optic (EO) polymer refilled silicon slot photonic crystal waveguide (PCW), together with broadband electric field enhancement provided by the bowtie antenna, are utilized to enhance the interaction of microwaves and optical waves, enabling an ultra large effective in-device EO coefficient over 1000 pm/V and thus a high sensitivity. The EO polymer refilled slot PCW is designed for low-dispersion slow-light propagation, high poling efficiency, and high optical mode confinement inside the slot. The bowtie antenna acts not only as a receiving antenna, but also as poling electrodes during the fabrication process. A bowtie antenna integrated on doped silicon slot PCW is demonstrated to have a broad operational bandwidth, with a maximum resonance at the frequency of 10 GHz. The strongly enhanced broadband electric field is used to directly modulate the phase of the optical waves propagating through the slot PCW embedded inside the feed gap of the bowtie antenna. The phase modulation is then converted to intensity modulation using an external reference arm to form a Mach-Zehnder interferometer in our experimental setup. The sensing of electromagnetic field at 8.4 GHz is experimentally demonstrated, with a minimum detectable electromagnetic power density of $8.4\, {\rm mW\!/\!m}^{2}$ , corresponding to a minimum detectable electric field of 2.5 V/m.

In this paper, we outline China's imported inflation via global commodity prices. We show that the prices of China's imported commodities are strongly related to global commodity prices. Meanwhile, the final goods prices from upstream industries are strongly influenced by global commodity prices. However, this effect is partially offset by the production process—that is, the final goods prices in downstream industries are generally less affected by global prices. This indicates that China's commodity market has a close link with global commodity markets. Therefore, high global commodity prices generally squeeze profits in China's downstream industries; upstream industries generally benefit from high global commodity prices.

Accurate region of interest (ROI) extraction is a hotspot of remote sensing image analysis. In this paper, we propose a novel ROI extraction method based on multi-scale hybrid visual saliency analysis (MHVSA) that can be divided into two sub-models: the frequency feature analysis (FFA) model and the multi-scale region aggregation (MRA) model. In the FFA sub-model, we utilize the human visual sensitivity and the Fourier transform to produce the local saliency map. In the MRA sub-model, saliency maps of various scales are generated by aggregating regions. A tree-structure graphical model is suggested to fuse saliency maps into one global saliency map. We obtain two binary masks by segmenting the local and global saliency maps and perform the logical AND operation on the two masks to acquire the final mask. Experimental results reveal that the MHVSA model provides more accurate extraction results.

We propose a reflection type metal-insulator-metal (MIM) metasurface composed of hybrid nano-antennas for comprehensive spatial engineering of the properties of optical fields. The capability of such structure is illustrated in the design of a device that can be used to produce a radially polarized vectorial beam for optical needle field generation. This device consists of uniformly segmented sectors of high efficiency MIM metasurface. With each of the segment sector functioning as a local quarter-wave-plate (QWP), the device is designed to convert circularly polarized incidence into local linear polarization to create an overall radial polarization with corresponding binary phases and extremely high dynamic range amplitude modulation. The capability of such devices enables the generation of nearly arbitrarily complex optical fields that may find broad applications that transcend disciplinary boundaries.

Haze removal has become an attractive topic in recent years and several dehazing methods are proposed. Dark channel prior (DCP) is one of the most effective dehazing approaches. However, when dealing with images containing large white objects, DCP often mistakes white objects for opaque haze. It will cause the airlight to be overestimated and the transmission to be underestimated, and thus the dehazing results have serious color distortion. In view of the above problem, saliency detection is introduced into haze removal to obtain better restored images in this paper. We first propose a method for reliable airlight estimation. Then, a saliency prior is presented for hazy images, which can distinguish white objects from dense haze by saliency detection. On the basis of saliency prior, both accurate airlight and a correct transmission map can be obtained from images containing large white objects, and finally these images can be restored successfully. The experimental results illustrate that our proposed method has great superiority in color recovery compared with other state-of-art methods when dealing with images containing large white objects.

We propose a reflection type metal-insulator-metal (MIM) metasurface composed of hybrid optical antennas for comprehensive spatial engineering the properties of optical fields. Its capability is illustrated with an example to create a radially polarized vectorial beam for optical needle field generation. Functioning as local quarter-wave-plates (QWP), the MIM metasurface is designed to convert circularly polarized incident into local linear polarization to create an overall radial polarization with corresponding binary phases and desired normalized amplitude modulation ranged from 0.07 to 1. To obtain enough degrees of freedom, the optical-antenna layer comprises periodic arrangements of double metallic nano-bars with perpendicular placement and single nano-bars respectively for different amplitude modulation requirements. Both of the antennas enable to introduce π/2 retardation while reaching the desired modulation range both for phase and amplitude. Through adjusting the antennas’ geometry and array carefully, we shift the gap-surface plasmon resonances facilitated by optical antennas to realize the manipulation of vectorial properties. Designed at 1064 nm wavelength, the particularly generated vectorial light output can be further tightly focused by a high numerical aperture objective to obtain longitudinally polarized flat-top focal field. The so-called optical needle field is a promising candidate for novel applications that transcend disciplinary boundaries. The proposed metasurface establishes a new class of compact optical components based on nano-scale structures, leading to compound functions for vectorial light generation.

In this work, we design, fabricate and characterize a compact, broadband and highly sensitive integrated photonic electromagnetic field sensor based on a silicon-organic hybrid modulator driven by a bowtie antenna. The large electro-optic (EO) coefficient of organic polymer, the slow-light effects in the silicon slot photonic crystal waveguide (PCW), and the broadband field enhancement provided by the bowtie antenna, are all combined to enhance the interaction of microwaves and optical waves, enabling a high EO modulation efficiency and thus a high sensitivity. The modulator is experimentally demonstrated with a record-high effective in-device EO modulation efficiency of r33=1230pm/V. Modulation response up to 40GHz is measured, with a 3-dB bandwidth of 11GHz. The slot PCW has an interaction length of 300um, and the bowtie antenna has an area smaller than 1cm2. The bowtie antenna in the device is experimentally demonstrated to have a broadband characteristics with a central resonance frequency of 10GHz, as well as a large beam width which enables the detection of electromagnetic waves from a large range of incident angles. The sensor is experimentally demonstrated with a minimum detectable electromagnetic power density of 8.4mW/m2 at 8.4GHz, corresponding to a minimum detectable electric field of 2.5V/m and an ultra-high sensitivity of 0.000027V/m Hz^-1/2 ever demonstrated. To the best of our knowledge, this is the first silicon-organic hybrid device and also the first PCW device used for the photonic detection of electromagnetic waves. Finally, we propose some future work, including a Teraherz wave sensor based on antenna-coupled electro-optic polymer filled plasmonic slot waveguide, as well as a fully packaged and tailgated device., Comment: 20 pages, 16 figures

The bowtie antenna is a topic of growing interest in recent years. In this paper, we design, fabricate, and characterize a modified gold bowtie antenna integrated on a transparent glass substrate. We numerically investigate the antenna characteristics, specifically its resonant frequency and enhancement factor. We simulate the dependence of resonance frequency on bowtie geometry, and verify the simulation results through experimental investigation, by fabricating different sets of bowtie antennas on glass substrates utilizing CMOS compatible processes and measuring their resonance frequencies. Our designed bowtie antenna provides a strong broadband electric field enhancement in its feed gap. The far-field radiation pattern of the bowtie antenna is measured, and it shows dipole-like characteristics with large beam width. Such a broadband antenna will be useful for a myriad of applications, ranging from wireless communications to electromagnetic wave detection., 8 pages, 7 figures, SPIE Photonics West Conference

We demonstrate an integrated photonic electromagnetic field sensor based on an electro-optic polymer infiltrated slot photonic crystal waveguide modulator. The minimum detectable electric field is measured to be 2.5V/m at 8.4GHz.

Relay selection has been regarded as an effective method to improve the performance of cooperative communication system. However, frequent operation of relay selection can bring enormous control message overhead and thereby decrease the performance of cooperative communication. To reduce the relay selection frequency, in this paper, we propose a relay selection scheme to choose the best relay with considering successive packets transmission. In this scheme, according to the length of data packet, data transmission rate and the estimated channel state information (CSI), the best relay is selected to maximize the number of successive packets transmission under the condition that the given symbol-error-rate (SER) is kept. Finally, numerical results show that the proposed relay selection scheme can support the operation of successive packets transmission in cooperative wireless networks and that the maximum number of successive packets transmission is affected by the different network parameters, i.e., data transmission rate, packet length and Doppler frequency at one relay node.

Objective : To expand on a preliminary study comparing the chemotactic potential of peritoneal fluid (PF) from women with and without endometriosis and to characterize this activity via immunosuppressants and a protease. Design : Case control study. Setting : University center. Patient(s) : Fifty-nine women with endometriosis and 44 without, undergoing laparoscopy. Intervention(s) : Collection of PF, endometriotic, ovarian, and endometrial biopsies at laparoscopy. Main Outcome Measure(s) : Chemotactic activity of PF was tested via an in vitro assay alone and in the presence of immunosuppressants cyclosporin A (CSA), FK506, rapamycin, and type XVII-b(S-V8) protease and in media incubated with endometriotic, ovarian, or endometrial biopsy specimens. Result(s) : The PF from women with endometriosis had significantly greater chemotactic activity (cells per well, mean ± SD) than without endometriosis (142 ± 39 versus 48 ± 17). Cyclosporin A significantly inhibited the chemotactic activity of the endometriotic PF; FK506 and rapamycin did not. Incubation of media with endometriotic tissue, but not ovarian or endometrial, for ≥ 7 hours displayed chemotactic activity. Protease type XVII-b(S-V8) added to endometriotic PF inhibited this chemotactic activity. Conclusion(s) : Peritoneal fluid from patients with endometriosis contains a protein chemotactic factor attracting inflammatory cells into the peritoneal cavity, possibly secreted by endometriotic implants. This chemotactic factor may be a member of the immunophilin family because of its inhibition profile.

We present a novel design of a subwavelength modified bow-tie antenna that is capable of generating strong broadband field enhancement in its extended feed gap. This modified bow-tie antenna is comprised of a conventional bow-tie antenna with capacitive extended bars attached to the apex points of the bow-tie. The feed gap between the two capacitive bars is separated with a deep subwavelength width for the generation of enhanced local electrical field. Three-dimensional finite element method model is utilized to systematically explore the properties of this antenna design. Through adjusting the bow-tie geometry and the substrate properties, the antenna structure is optimized with a central resonant frequency at 100 GHz. Highly enhanced electrical field is created between the extended bar under radio frequency (RF) illumination. With the optimized design, numer ical simulations show that a uniform field enhancement of more than 200 through the entire feed gap with a bandw idth of 40 GHz can be achiev ed. The strongly enhanced RF field within the gap can be applied to directly modulate guided optical wave propagating in a waveguide embedded in the substrate underneath the feed gap. This work builds up a bridge between devices in the RF and optical frequency regimes that may find many potential applications in RF photonic devices and systems. Keywords: Modified bow-tie antenna, broadband strong field enhancement, RF photonic applications

We present the design of a compact and highly sensitive electric field sensor based on a bowtie antenna-coupled slot photonic crystal waveguide (PCW). An electro-optic (EO) polymer with a large EO coefficient, r33=100pm/V, is used to refill the PCW slot and air holes. Bowtie-shaped electrodes are used as both poling electrodes and as receiving antenna. The slow-light effect in the PCW is used to increase the effective in-device r33>1000pm/V. The slot PCW is designed for low-dispersion slow light propagation, maximum poling efficiency as well as optical mode confinement inside the EO polymer. The antenna is designed for operation at 10GHz., 7 pages, 5 figures, conference. "Electric field sensor based on electro-optic polymer refilled silicon slot photonic crystal waveguide coupled with bowtie antenna," Proc. SPIE 8624, 862418 (2013)

A vectorial optical field generator (VOF-Gen) based on two reflective phase-only liquid crystal spatial light modulators enables the creation of an arbitrary optical complex field. In this work, the capabilities of the VOF-Gen in terms of manipulating the spatial distributions of phase, amplitude, and polarization are experimentally demonstrated by generating a radially polarized optical field consisted of five annular rings, the focusing properties of which are also numerically studied with vectorial diffraction theory. By carefully adjusting the relative amplitude and phase between the adjacent rings, an optical needle field with purely longitudinal polarization can be produced in the focal region of a high numerical aperture lens. The versatile method presented in this work can be easily extended to the generation of a vectorial optical field with any desired complex distributions.

Discrete digital image can achieve exact histogram specification through the strict ordering algorithm in [1]. However, some edge information will be weakened. In this paper, a nonlinear filter algorithm in wavelet domain is proposed, which can solve the problem significantly. Firstly, the proposed approach utilizes wavelet transform to decompose the image and extract the wavelet coefficients. Secondly, exact histogram specification is implemented to low frequency coefficients, and a nonlinear filter algorithm is applied to enhance high frequency wavelet coefficients of different directions. Finally, the image fulfilled with exact histogram specification and enhancement of edge information is obtained through the inverse wavelet transform. Experimental results show that this method is effective for exact histogram specification and enhancing edge information simultaneously.

A transmission-type metasurface composed of carefully designed rectangular slot antennas for the generation of vectorial optical fields is proposed and demonstrated. Acting as local linear polarizers, these slot antennas enable the spatial modulation of optical fields in amplitude, phase, and polarization for the cross-polarized component of the scattered field. As an illustration, a metasurface capable of forming a radially polarized scattered field with specific vectorial beam patterns with appropriate excitation at normal incidence is designed, fabricated, and tested. The radially polarized scattered field is designed to be further tightly focused by a high numerical aperture objective lens in order to obtain a uniform longitudinally polarized optical needle field along the propagation direction. Characterization experiments demonstrate that its overall extinction ratio satisfies the amplitude modulation requirement, and a corresponding π phase modulation is realized as proposed.

We demonstrate an integrated photonic electric field sensor based on an electro-optic polymer refilled silicon slot photonic-crystal waveguide modulator driven by a bowtie-antenna. The minimum detectable electric field is measured to be 2.5V/m at 8.4GHz.