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Prunella vulgaris L. is a perennial herb plant of the Lamiaceae family, and its dried spicas have been widely used as medicine, health-promoting food or tea around the world. P. vulgaris is distributed all over the world, such as Europe, Asia, northwestern Africa and North America, as well as the Huaihe River Basin and the middle and lower Yangtze River Basin in China. In February 2022, a serious disease like gray mold occurred in planting fields of P. vulgaris in Wuhan, Hubei (N30°27′07″, E114°15′49″), causing approximately 20% of plants were diseased in the field. Early symptoms were characterized by small, round gray-brown lesions on the leaves of P. vulgaris. Later, a large number of stems and leaves are wilted or necrotic, associated with wet rot and waterlogged spots and covered with light gray or grayish white flocculent mildew layer. To determine the causal agent of disease, 10 plants with the typical symptoms were collected from fields. The stems and leaves of diseased plants were cut into pieces (2 to 3 mm×5 mm), disinfected with 75% ethanol for 3 minutes, rinsed 3 times with sterile water. Each lesion sample was isolated and purified using separate PDA petri dishes at 25°C, and ultimately all samples yielded morphologically consistent pure strain colonies. From the 10 isolates obtained, XKC-1 was chosen as a representative isolate for further study. XKC-1 colonies showed gray aerial mycelia, which were fast-growing and grew over the whole plate (9 cm) after 4 days. In addition, some black and hard sclerotia (1.88±0.94 mm, n=50) with round or irregular shape developed on the colonies after approximately 10 days of incubation at 25°C (Fig. 2A, B). XKC-1 showed branched conidiophores with enlarged apical cells and numerous conidia (Fig. 2C). Unicellular conidia were colorless or gray, ellipsoid or ovoid, smooth and 7.91-12.38 μm × 10.08-13.82 μm (n=30) in size (Fig. 2D). Based on morphological characteristics, the isolate was initially identified as Botrytis sp. (Ellis 1971). To further identify the species, the genomic DNA of XKC-1 was extracted, and the ITS, LSU and G3PDH genes were amplified with the primers ITS1/ITS4, LROR/LR5 (Zhou et al. 2022) and G3PDH-F/G3PDH-R (Jin et al. 2022), respectively. The results indicated that the ITS (ON090404), LSU (ON090417), and G3PDH (ON169893) sequences were 99.80%, 100% and 99.46% identical to the sequences of Botrytis cinerea Pers. strain (MK370693.1, MN148533.1, MN630267.1), respectively. A phylogenetic tree constructed based on a concatenated sequence (ITS, LSU, G3PDH) using the neighbor-joining method in MEGA7 (Tamura et al. 2013) revealed that XKC-1 grouped with concatenated sequences from three representative B. cinerea isolates in GenBank. Based on the morphological characteristics and molecular identification, the strain XKC-1 was identified as Botrytis cinerea. For pathogenicity tests on detached leaves, 5 mm PDA cakes prepared from XKC-1 were placed on the leaves obtained from healthy P. vulgaris after wounding with a needle (n=10), while PDA medium without mycelia were used as control (25 ± 2°C) (Li et al.2020). Mycelia began to germinate and infect plant tissues at 1 dpi. A large part of the leaves showed water soaked spots covered with mycelia on the surface at 4 dpi. For whole plant inoculations, stem bases of five P. vulgaris seedlings were pierced with sterile needle, and then inoculated with three XKC-1 mycelium PDA cakes. Five plants were inoculated with three PDA cakes without mycelia as a control. After 2-4 days, lesions appeared on the leaves and covered with a gray-white mycelial layer, similar to those observed in the field. However, controls remained symptom free. The pathogen was reisolated from the diseased tissues, the colonies, microscopic characteristics and molecular identification were consistent with those of XKC-1. To our knowledge, this is a first report of B. cinerea causing gray mold on P. vulgaris in Hubei, China. This report would provide resources and reference for controlling of the increased incidence and economic losses of gray mold on P. vulgaris.

B cells can be polarized to express various cytokines. The roles of IFNγ and IL-10, expressed respectively by B effector 1 (Be1) and Bregs, have been established in pathogen clearance, tumor growth, autoimmunity and allograft rejection. However, the

Wide-angle and broadband antireflection (AR) coating is of the essence in modern optical systems in many fields, which has a great influence on the stray light and imaging quality. A simple and convenient manufacturing method is proposed to address this issue based on a composite coating combining the nano-tapered Al2O3•xH2O (AH) structure and high-low index thin film stack. The optical properties of nano-tapered AH structure at various thickness are first studied and modeled in optics by several homogeneous sub-layers with the graded equivalent index. The designed composite AR coatings are manufactured by vacuum deposition and wet etching subsequently in the hot deionized water. Compared to the common dielectric multilayer antireflection stack, the composite coating presents excellent AR performance. The measured average reflectance values of the double-side coated BK7 glass are as low as 0.40%, 0.41%, 0.56% and 3.13% in 400-1100nm band at angles of incidence (AOI) of 6°, 20°, 40°, and 60°, respectively, while the measured average transmittance at normal incidence increases up to 99.3%. Finally, the process reproductivity, environmental reliability test including long term storage, high temperature annealing and 85°C-85% relative humidity storage of the composite coatings are evaluated. The proposed AR scheme provides a low-cost, efficient, wide-angle and broadband AR coating for kinds of large-curvature components and complex surfaces in fields of consumer electronics, automotive, security, etc.

We present a high-dispersive multilayer mirror for pulse stretching in a femtosecond fiber laser amplification system. The designed mirror contains 54 layers with a total physical thickness of 7.3 μm, which can provide a positive group delay dispersion (GDD) of 600 fs2 and a high reflectance over 99.9% from 1010 to 1070 nm. The samples were prepared by dual ion beam sputtering. The measured transmittance matches well with the theoretical result. The GDD characteristics of samples were tested by home-made white light interferometer. The measured GDD is higher than the design results, an average GDD of +722 fs2 from 1010 nm to 1070 nm. The mirrors were employed in a Yb-doped large-mode-area photonic crystal fiber amplification system. An input pulse compressed by the gratings with autocorrelation function of 83 fs is obtained with a stretched FWHM of 1.29 ps after 28 bounces between the dispersive mirrors. The results show that the multilayer dispersive mirror could be an effective and promising technique for pulse stretching in femtosecond amplification systems.

International audience; WUSCHEL-related homeobox (WOX) genes are key regulators of meristem activity and plant development, the chromatin mechanism of which to reprogram gene expression remains unclear. Histone H3K27me3 is a chromatin mark of developmentally repressed genes. How the repressive mark is removed from specific genes during plant development is largely unknown. Here, we show that WOX11 interacts with the H3K27me3 demethylase JMJ705 to activate gene expression during shoot development in rice. Genetic analysis indicates that WOX11 and JMJ705 cooperatively control shoot growth and commonly regulate the expression of a set of genes involved in meristem identity, chloroplast biogenesis, and energy metabolism in the shoot apex. Loss of WOX11 led to increased H3K27me3 and overexpression of JMJ705 decreased the methylation levels at a subset of common targets. JMJ705 is associated with most of the WOX11-binding sites found in the tested common targets in vivo, regardless of presence or absence of the JMJ705-binding motif. Furthermore, wox11 mutation reduced JMJ705-binding to many targets genome-wide. The results suggest that recruitment of JMJ705 to specific developmental pathway genes is promoted by DNA-binding transcription factors and that WOX11 functions to stimulate shoot growth through epigenetic reprogramming of genes involved in meristem development and energy-generating pathways.

Applications on wearable personal imaging devices, or Smart-glasses as they are called, can largely benefit from accurate and energy-efficient recognition of objects that are within the user's view. Existing solutions such as optical or computer vision approaches are too energy intensive, while low-power active radio tags suffer from imprecise orientation estimates. To address this challenge, this paper presents the design, implementation, and evaluation of a radio-optical hybrid system where a radio-optical transmitter, or tag , whose radio-optical beacons are used for accurate relative orientation tracking of tagged objects by a wearable radio-optical receiver. A low-power radio link that conveys identity is used to reduce the battery drain by synchronizing the radio-optical transmitter and receiver so that extremely short optical (infrared) pulses are sufficient for orientation (angle and distance) estimation. Through extensive experiments with our prototype we show that our system can achieve orientation estimates with 1-to-2 degree accuracy and within 40 cm ranging error, with a maximum range of 9 m in typical indoor use cases. With a tag and receiver battery power consumption of 81 $\mu$ W and 90 mW, respectively, our radio-optical tags and receiver are at least 1.5 $\times$ energy efficient than prior works in this space.

A non-polarizing beam splitter and a light color-mixing challenge were the topics of the design contest held in conjunction with the 2019 Optical Interference Coatings topical meeting of the Optical Society of America. A total of 10 designers from China, France, Germany, Japan, and the United States submitted over 70 designs for problems A and B. The design problems and the submitted solutions are described and evaluated.

Cameras are ubiquitous and increasingly being used not just for capturing images but also for communicating information. For example, the pervasive QR codes can be viewed as communicating a short code to camera-equipped sensors. Such communications could be particularly attractive in pervasive camera based applications, where such camera communications can reuse the existing camera hardware and also leverage from the large pixel array structure for high data-rate communication. While several prototypes have been constructed, the fundamental capacity limits of the screen-camera communication channel in all but the simplest scenarios remains unknown. The visual medium differs from RF in that the information capacity of this channel largely depends on the perspective distortions while multipath becomes negligible. In this paper, we create a model of this communication system to allow predicting the capacity based on receiver perspective (distance and angle to the transmitter). We calibrate and validate this model through lab experiments wherein information is transmitted from a screen and received with a tablet camera. Our capacity estimates indicate that tens of Mbps is possible using a smartphone camera even when the short code on the screen images onto only 15% of the camera frame. Our estimates also indicate that there is room for at least 2.5 i? improvement in throughput of existing screen-camera communication prototypes.

A dispersive mirror and a coating uniformity challenge were the topics of the design contest held in conjunction with the 2016 Optical Interference Coatings topical meeting of The Optical Society (OSA). A total of 18 designers from China, France, Germany, Japan, and the United States submitted 38 total designs for problems A and B. Michael Trubetskov submitted the winning designs for all four design challenges. The design problems and the submitted solutions are described and evaluated.

Object recognition on wearable devices using computer vision is too energy intensive and challenging when objects are similar looking, while low-power active radio frequency identification (RFID) systems suffer from imprecise orientation (angle and distance) estimates. To address this challenge, this paper presents a novel radio-optical based recognition system where a radio-optical transmitter, or tag, that emits a beacon whose infra-red (IR) signal strength is used for accurate relative orientation tracking of tagged objects at a wearable radio-optical receiver. A low-power radio link that conveys identity is used to reduce the battery drain by synchronizing the radio- optical transmitter and receiver so that extremely short optical pulses are sufficient for precise orientation estimation. Through extensive experiments with our prototype we show that our system can achieve orientation estimates with 1-2 degree accuracy and within 40cm ranging error, with a maximum range of 9m in typical indoor use cases. With a tag battery power consumption of 86µW, the radio-optical tags show potential to achieve about half a decade lifetimes.

We present a novel method for communicating between a camera and display by embedding and recovering hidden and dynamic information within a displayed image. A handheld camera pointed at the display can receive not only the display image, but also the underlying message. These active scenes are fundamentally different from traditional passive scenes like QR codes because image formation is based on display emittance, not surface reflectance. Detecting and decoding the message requires careful photometric modeling for computational message recovery. Unlike standard watermarking and steganography methods that lie outside the domain of computer vision, our message recovery algorithm uses illumination to optically communicate hidden messages in real world scenes. The key innovation of our approach is an algorithm that performs simultaneous radiometric calibration and message recovery in one convex optimization problem. By modeling the photometry of the system using a camera-display transfer function (CDTF), we derive a physics-based kernel function for support vector machine classification. We demonstrate that our method of optimal online radiometric calibration (OORC) leads to an efficient and robust algorithm for computational messaging between nine commercial cameras and displays., Comment: 10 pages, Submitted to CVPR 2015

The ubiquity of cameras in today's world has played a key role in the growth of sensing technology and mobile computing. However, on the other hand, it has also raised serious concerns about privacy of people who are photographed, intentionally or unintentionally. The popularity of publishing pictures in social networks adds to the concern that the photographed user has the least control over his/her picture. In this paper, we present the design, implementation and evaluation of "invisible light beacons" where privacy preferences of photographed users are communicated to photographing cameras. Particularly, we explore a design where the beacon transmitters are worn by users on their eye-wear and transmit a privacy code through ON-OFF patterns of light beams from IR LEDs. The beacons are received and decoded by a camera and mapped to different privacy preferences corresponding to that code. Based on the experimental evaluation of thousands of data points using our prototype implementation we show that the detection accuracy of a known privacy code is greater than 98%, and error rate of communicating a random stream of bits over an indoor IR-camera channel is within 7% at packet level and of the order of 10-3 at bit level.

Ubiquitous light emitting devices and low-cost commercial digital cameras facilitate optical wireless communication system such as visual MIMO where handheld cameras communicate with electronic displays. While intensity-based optical communications are more prevalent in camera-display messaging, we present a novel method that uses modulated light phase for messaging and time-of-flight (ToF) cameras for receivers. With intensity-based methods, light signals can be degraded by reflections and ambient illumination. By comparison, communication using ToF cameras is more robust against challenging lighting conditions. Additionally, the concept of phase messaging can be combined with intensity messaging for a significant data rate advantage. In this work, we design and construct a phase messaging array (PMA), which is the first of its kind, to communicate to a ToF depth camera by manipulating the phase of the depth camera's infrared light signal. The array enables message variation spatially using a plane of infrared light emitting diodes and temporally by varying the induced phase shift. In this manner, the phase messaging array acts as the transmitter by electronically controlling the light signal phase. The ToF camera acts as the receiver by observing and recording a time-varying depth. We show a complete implementation of a 3×3 prototype array with custom hardware and demonstrating average bit accuracy as high as 97.8%. The prototype data rate with this approach is 1 Kbps that can be extended to approximately 10 Mbps., National Science Foundation (U.S.) (grant CNS-106546#)

Cameras are ubiquitous and increasingly being used not just for capturing images but also for communicating information. For example, the pervasive QR codes can be viewed as communicating a short code to camera-equipped sensors and recent research has explored using screen-to-camera communications for larger data transfers. Such communications could be particularly attractive in pervasive camera based applications, where such camera communications can reuse the existing camera hardware and also leverage from the large pixel array structure for high data-rate communication. While several prototypes have been constructed, the fundamental capacity limits of this novel communication channel in all but the simplest scenarios remains unknown. The visual medium differs from RF in that the information capacity of this channel largely depends on the perspective distortions while multipath becomes negligible. In this paper, we create a model of this communication system to allow predicting the capacity based on receiver perspective (distance and angle to the transmitter). We calibrate and validate this model through lab experiments wherein information is transmitted from a screen and received with a tablet camera. Our capacity estimates indicate that tens of Mbps is possible using a smartphone camera even when the short code on the screen images onto only 15% of the camera frame. Our estimates also indicate that there is room for at least 2.5x improvement in throughput of existing screen - camera communication prototypes.

Modern society has ubiquitous electronic displays including billboards, signage and kiosks. The concurrent prevalence of handheld cameras creates a novel opportunity to use cameras and displays as communication channels. The electronic display in this channel serves a twofold purpose: to display an image to humans while simultaneously transmitting hidden bits for decoding by a camera. Unlike standard digital watermarking, the message recovery in camera-display systems requires physics-based modeling of image formation in order to optically communicate hidden messages in real world scenes. By modeling the photometry of the system using a camera-display transfer function (CDTF), we show that this function depends on camera pose and varies spatially over the display.We devise a radiometric calibration to handle the nonlinearities of both the display and the camera, and we use this method for recovering video messages hidden within display images. Results are for 9 different display-camera systems for messages with 4500 bits. Message accuracy improves significantly with calibration and we achieve accuracy near 99% in our experiments, independent of the type of camera or display used.

Augmented Reality (AR) applications benefit from accurate detection of the objects that are within a person's view. Typically, it is not only desirable to identify what is currently within view, but also to navigate the users view to the item of interest - for example, finding a misplaced object. In this paper we demonstrate a low-power hybrid radio-optical beaconing system, where objects of interest are tagged with battery-powered RFID-like tags equipped with infrared light emitting diodes (LED) that emit periodic infrared beacons. These beacons are used for accurately estimating the angle and distance from the object to the receiver so as to locate it. The beacons are synchronized using the radio link that is also used to convey the object's unique ID.

Transparent conductive indium tin oxide thin films with thickness around 200 nm were deposited on glass substrates by pulsed laser deposition technology. The microstructure and the electrical and optical properties of the ITO films deposited under different oxygen pressures and substrate temperatures were systematically investigated. Distinct different x-ray diffraction patterns revealed that the crystallinity of ITO films was highly influenced by deposition conditions. The highest carrier concentration of the ITO films was obtained as 1.34 × 10(21) cm(-3) with the lowest corresponding resistivity of 2.41 × 10(-4) Ω cm. Spectroscopic ellipsometry was applied to retrieve the dielectric permittivity of the ITO films to estimate their potential as plasmonic materials in the near-infrared region. The crossover wavelength (the wavelength where the real part of the permittivity changes from positive to negative) of the ITO films exhibited high dependence on the deposition conditions and was optimized to as low as 1270 nm. Compared with noble metals (silver or gold etc), the lower imaginary part of the permittivity (

The inherent limitations in RF spectrum availability and susceptibility to interference make it difficult to meet the reliability required for automotive safety applications. To address this challenge, this work explores an alternative communication system called Visual MIMO that uses light emitting arrays as transmitters and cameras as receivers. Visual MIMO applied to vehicular communication proposes to reuse existing LED rear and headlights as transmitters and existing cameras (e.g. those used for parking assistance, rear-view cameras) as receivers. In this work we show a proof of concept based demonstration of the Visual MIMO system consisting of an LED transmitter array and a high-speed camera.

We propose a rate adaptation scheme for visual MIMO camera-based communications, wherein parallel data transmissions from light emitting arrays are received by multiple receive elements of a CCD/CMOS camera image sensor. Unlike RF MIMO, multipath fading is negligible in the visual MIMO channel. Instead, the channel is largely dependent on receiver perspective (distance and angle) and visibility issues (partial line-of-sight availability and occlusions). This allows for slower adaptation but requires the adaptation algorithm to choose among a more complex set of modes. In this paper, we define a set of operating modes for visual MIMO transmitters and propose a rate adaptation scheme to switch between these modes. Our Visual MIMO Rate Adaptation (VMRA) is a packet based rate adaptation protocol that bases its rate selection decisions on the packet error rate feedback. Using trace-based simulation results for a vehicle-to-vehicle communication scenario, we illustrate how our VMRA algorithms can adapt over distance as well as visibility variations in an optical link and achieve a higher average throughput.

Cameras have become commonplace in phones, laptops, music-players and handheld games. Similarly, light emitting displays are prevalent in the form of electronic billboards, televisions, computer monitors, and hand-held devices. The prevalence of cameras and displays in our society creates a novel opportunity to build camera-based optical wireless communication systems based on a concept called visual MIMO. We extend the common term MIMO from the field of communications (“multiple-input multiple-output”) that is typically used to describe multiple antenna, multiple transmitter radio frequency communications channel. In the visual MIMO communications paradigm, the transmitters are light-emitting devices such as electronic displays and cameras are the receivers. In this paper we discuss and address several challenges in creating a visual MIMO channel. These challenges include: (1) electronic display detection, (2) embedding the transmission signal in the display video, and (3) system characterization for electronic display appearance.