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Katarzyna Piórkowska, Kacper Żukowski, Katarzyna Ropka-Molik, Mirosław Tyra, Artur Gurgul
Pork is the most popular meat in the world. Unfortunately, the selection pressure focused on high meat content led to a reduction in pork quality. The present study used RNA-seq technology to identify metabolic process genes related to pork quality traits and fat deposition. Differentially expressed genes (DEGs) were identified between pigs of Pulawska and Polish Landrace breeds for two the most important muscles (semimembranosus and longissimus dorsi). A total of 71 significant DEGs were reported: 15 for longissimus dorsi and 56 for semimembranosus muscles...
January 2018: Genetics and Molecular Biology
Grigoriy Zurakhov, Ling Tong, Alessandro Ramalli, Piero Tortoli, Jan D'hooge, Zvi Friedman, Dan Adam
Increased frame rate is of high importance to cardiac diagnostic imaging as it enables examination of fast events during the cardiac cycle and improved quantitative analysis, such as speckle tracking. Multiline transmission (MLT) is one of the methods proposed for this purpose. In contrast to the single-line transmission (SLT), where one focused beam is sent in each direction, MLT beams are simultaneously transmitted and focused in several ( ) directions improving the frame rate accordingly. The simultaneous transmission is known to cause crosstalk artifacts due to the interference between the main lobes and the sidelobes of the transmitted and received beams...
April 2018: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Jeongmin Kim, Yuan Wang, Xiang Zhang
In light focusing through a dielectric interface, Wiersma et al. [J. Opt. Soc. Am. A14, 1482 (1997)JOAOD60740-323210.1364/JOSAA.14.001482] claim that the Debye-Wolf diffraction theory and the m-theory predict axial focal fields with "little difference." We found a possible mistake of using an inaccurate apodization factor in the m-theory integral. Here we correct the apodization factor, which then leads to better agreement on axial intensity distributions between the two theories than reported.
April 1, 2018: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Juan José Mompó, Sonia Martín-López, Miguel González-Herráez, Alayn Loayssa
We demonstrate a technique to reduce the sidelobes in optical pulse compression reflectometry for distributed acoustic sensing. The technique is based on using a Gaussian probe pulse with linear frequency modulation. This is shown to improve the sidelobe suppression by 13 dB compared to the use of square pulses without any significant penalty in terms of spatial resolution. In addition, a 2.25 dB enhancement in signal-to-noise ratio is calculated compared to the use of receiver-side windowing. The method is tested by measuring 700 Hz vibrations with a 140  nε amplitude at the end of a 50 km fiber sensing link with 34 cm spatial resolution, giving a record 147,058 spatially resolved points...
April 1, 2018: Optics Letters
Sigal Kfir, Raghavendra Basavaraja, Noa Wigoda, Shifra Ben-Dor, Irit Orr, Rina Meidan
To unveil novel global changes associated with corpus luteum (CL) maturation, we analyzed transcriptome data for the bovine CL on days 4 and 11, representing the developing vs. mature gland. Our analyses revealed 681 differentially expressed genes (363 and 318 on day 4 and 11, respectively), with ≥2 fold change and FDR of <5%. Different gene ontology (GO) categories were represented prominently in transcriptome data at these stages (e.g. days 4: cell cycle, chromosome, DNA metabolic process and replication and on day 11: immune response; lipid metabolic process and complement activation)...
2018: PloS One
Emilio Pedrotti, Francesco Carones, Francesco Aiello, Rodolfo Mastropasqua, Enrico Bruni, Erika Bonacci, Pietro Talli, Carlo Nucci, Cesare Mariotti, Giorgio Marchini
PURPOSE: To compare the visual acuity, refractive outcomes, and quality of vision in patients with bilateral implantation of 4 intraocular lenses (IOLs). SETTINGS: Department of Neurosciences, Biomedicine and Movement Sciences, Eye Clinic, University of Verona, Verona, and Carones Ophthalmology Center, Milano, Italy. DESIGN: Prospective case series. METHODS: The study included patients who had bilateral cataract surgery with the implantation of 1 of 4 IOLs as follows: Tecnis 1-piece monofocal (monofocal IOL), Tecnis Symfony extended range of vision (extended-range-of-vision IOL), Restor +2...
February 2018: Journal of Cataract and Refractive Surgery
Cheryl Suwen Law, Siew Yee Lim, Abel Santos
This study presents a nanofabrication approach that enables the production of nanoporous anodic alumina distributed Bragg reflectors (NAA-DBRs) with finely engineered light filtering features across the spectral regions. The photonic stopband (PSB) of these NAA-based photonic crystal (PC) structures is precisely tuned by an apodization strategy applied during stepwise pulse anodization with the aim of engineering the effective medium of NAA-DBRs in depth. We systematically assess the effect of different fabrication parameters such as apodization function (i...
March 15, 2018: Scientific Reports
Minah Han, Byeongjoon Kim, Jongduk Baek
We investigate the detectability of breast cone beam computed tomography images using human and model observers and the variations of exponent, β, of the inverse power-law spectrum for various reconstruction filters and interpolation methods in the Feldkamp-Davis-Kress (FDK) reconstruction. Using computer simulation, a breast volume with a 50% volume glandular fraction and a 2mm diameter lesion are generated and projection data are acquired. In the FDK reconstruction, projection data are apodized using one of three reconstruction filters; Hanning, Shepp-Logan, or Ram-Lak, and back-projection is performed with and without Fourier interpolation...
2018: PloS One
Craig K Abbey, Frank W Samuelson, Rongping Zeng, John M Boone, Miguel P Eckstein, Kyle Myers
PURPOSE: This study investigates forced-localization of targets in simulated images with statistical properties similar to trans-axial sections of x-ray computed tomography (CT) volumes. A total of 24 imaging conditions are considered, comprising 2 target sizes, 3 levels of background variability, and 4 levels of frequency apodization. The goal of the study is to better understand how human observers perform forced-localization tasks in images with CT-like statistical properties. METHODS: The transfer properties of CT systems are modeled by a shift-invariant transfer function in addition to apodization filters that modulate high spatial frequencies...
March 12, 2018: Medical Physics
Min Liu, Zhou Li, Lu Liu
Sidelobe reduction is a very primary task for synthetic aperture radar (SAR) images. Various methods have been proposed for broadside SAR, which can suppress the sidelobes effectively while maintaining high image resolution at the same time. Alternatively, squint SAR, especially highly squint SAR, has emerged as an important tool that provides more mobility and flexibility and has become a focus of recent research studies. One of the research challenges for squint SAR is how to resolve the severe range-azimuth coupling of echo signals...
March 5, 2018: Sensors
Sebastian Romero-García, Alvaro Moscoso-Mártir, Juliana Müller, Bin Shen, Florian Merget, Jeremy Witzens
We present wideband and large free spectral range optical filters with steep passband edges for the selection of adjacent WDM communication channels that can be reliably fabricated with mainstream silicon photonics technology. The devices are based on three cascaded stages of coupled resonator optical waveguides loaded on a common bus waveguide. These stages differ in the number of resonators but are implemented with exactly identical unit cells, comprised of a matched racetrack resonator layout and a uniform spacing between cells...
February 19, 2018: Optics Express
Marcin Kieliszczyk, Bartosz Janaszek, Anna Tyszka-Zawadzka, Paweł Szczepański
In this paper we present the possibility of shaping the reflectivity characteristics of tunable hyperbolic metamaterials (THMMs). Using the example of voltage-sensitive graphene-based structures, we demonstrate the existence of spectral and spatial functionalities of edge and narrowband filters, controlled dynamically over a 3-5 μm spectral range, that are important for both civilian and military applications. We also demonstrate that the adoption of apodization techniques in the THMM design leads to a reduction in the sidelobe's parasitic effect in edge filters, as well as providing the means to reshape the overall reflectivity characteristics, which not only unveiled the tunable angle aperture functionality but also significantly increased the potential for tailoring optical properties of THMM nanostructures in general...
February 10, 2018: Applied Optics
Jia-Sheng Ye, Li-Juan Xie, Xin-Ke Wang, Sheng-Fei Feng, Wen-Feng Sun, Yan Zhang
We present a new feasible way to flatten the axial intensity oscillations for diffraction of a finite-sized Bessel beam, through designing a cardioid-like hole. The boundary formula of the cardioid-like hole is given analytically. Numerical results by the complete Rayleigh-Sommerfeld method reveal that the Bessel beam propagates stably in a considerably long axial range, after passing through the cardioid-like hole. Compared with the gradually absorbing apodization technique in previous papers, in this paper a hard truncation of the incident Bessel beam is employed at the cardioid-like hole edges...
January 22, 2018: Optics Express
Moshe Zadka, You-Chia Chang, Aseema Mohanty, Christopher T Phare, Samantha P Roberts, Michal Lipson
Current silicon photonics phased arrays based on waveguide gratings enable beam steering with no moving parts. However, they suffer from a trade-off between beam divergence and field of view. Here, we show a platform based on silicon-nitride/silicon that achieves simultaneously minimal beam divergence and maximum field of view while maintaining performance that is robust to fabrication variations. In addition, in order to maximize the emission from the entire length of the grating, we design the grating's strength by varying its duty cycle (apodization) to emit uniformly...
February 5, 2018: Optics Express
Zhaolou Cao, Chunjie Zhai, Shanshan Xu, Yunyun Chen
Bessel beams have been increasingly used for their advantages of non-diffraction and long focal depth. In this paper, we studied the propagation of on-axis and off-axis Bessel beams in a gradient-index medium. By expressing a Bessel beam in integral form, the analytical expression of an on-axis, decentered, and tilted Bessel beam through a paraxial optical system is derived with the ABCD matrix method and Collins diffraction integral formula. Main lobe size and trajectory of the zeroth- and second-order Bessel beam are obtained, demonstrating that the Bessel beam is focused by the gradient-index medium and its main lobe trajectory is exactly the same as the corresponding geometrical ray for both the decentered and tilted Bessel beam...
February 1, 2018: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Wei Zhang, Yang Wu, Hai-Jiao Dong, Jun-Jie Yin, Hui Zhang, Hao-An Wu, Li-Na Song, Yu Chong, Zhuo-Xuan Li, Ning Gu, Yu Zhang
Herein we reported Prussian blue nanoparticles (PBNPs) possess ascorbic acid oxidase (AAO)- and ascorbic acid peroxidase (APOD)-like activities, which suppressed the formation of harmful H2 O2 and finally inhibited the anti-cancer efficiency of ascorbic acid (AA). This newly revealed correlation between iron and AA could provide new insight for the studies of nanozymes and free radical biology.
March 1, 2018: Colloids and Surfaces. B, Biointerfaces
Nazmi A Mohammed, Hatem O El Serafy
This work targets a remarkable quasi-distributed temperature sensor based on an apodized fiber Bragg grating. To achieve this, the mathematical formula for a proposed apodization function is carried out and tested. Then, an optimization parametric process required to achieve the remarkable accuracy that is based on coupled mode theory (CMT) is done. A detailed investigation for the side lobe analysis, which is a primary judgment factor, especially in quasi-distributed configuration, is investigated. A comparison between elite selection of apodization profiles (extracted from related literatures) and the proposed modified-Nuttal profile is carried out covering reflectivity peak, full width half maximum (FWHM), and side lobe analysis...
January 10, 2018: Applied Optics
Tao Liu, Lingjie Wang, Jizhen Zhang, Qiang Fu, Xin Zhang
In this paper, we investigate the relationship between open-ring zones of the Fresnel zone plate and the pinhole rings of photon sieves (PSs). Numerical simulations show that the normalized diffraction fields near the focal point of an individual pinhole ring and the circular open-ring zone are the same. It is confirmed that the maximum diffraction efficiency of an open-ring zone is higher than that of the traditional pinhole ring. Meanwhile, pinhole rings have more flexibility for apodization filtering. Based on these key findings, we propose the design theory of an apodized diffractive optical element comprised of open-ring zones and pinholes...
January 1, 2018: Applied Optics
Nadia García-Mateo, Raquel Pascua-Maestro, Alberto Pérez-Castellanos, Concepción Lillo, Diego Sanchez, Maria D Ganfornina
To compact the extracellular sides of myelin, an important transition must take place: from membrane sliding, while building the wraps, to membrane adhesion and water exclusion. Removal of the negatively charged glycocalyx becomes the limiting factor in such transition. What is required to initiate this membrane-zipping process? Knocking-out the Lipocalin Apolipoprotein D (ApoD), essential for lysosomal functional integrity in glial cells, results in a specific defect in myelin extracellular leaflet compaction in peripheral and central nervous system, which results in reduced conduction velocity and suboptimal behavioral outputs: motor learning is compromised...
March 2018: Glia
Yulong Wang, Lijuan Xie, Jiasheng Ye, Wenfeng Sun, Xinke Wang, Shengfei Feng, Peng Han, Qiang Kan, Yan Zhang
We demonstrated a simple heart-shaped hole to tailor the axial intensity of a collimated laser beam. This hole is transformed from a soft-boundary one, which avoids the difficulty in fabricating the soft-boundary mask designed by the apodization method, as well as the interference problem caused by the pixel structure of the spatial light modulator. When a collimated light passes through this hole, its axial intensity oscillates less than 11% within a certain distance, while the fluctuation after the circular aperture is up to 200%...
December 1, 2017: Optics Letters
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