Ultra High Definition Research Articles

Transferability of laparoscopic skills acquired from three-dimensional high-definition and ultra-high definition endovision system to two-dimensional high-definition endovision system: an ex-vivo randomized study.

Three-dimensional high-definition (3D HD) and ultra-high-definition (4K HD) endovision systems are rapidly adopted in academic setting. However, transferability of laparoscopic skills acquired from these systems to two-dimensional high-definition (2D HD) endovision system is not known. Forty stereo-enabled surgical residents were randomized into two groups. They performed three standardized surgical tasks, Task 1(Peg transfer), Task 2(Precision touch on uneven surface) and Task 3(Surgical knotting on rubber tube) for 15 repetitions using either 3D HD or 4K HD. Both groups then performed the same tasks using 2D HD for 5 repetitions. Their performances were evaluated for execution time (speed) and error scores (safety). The residents in 3D HD group performed all three tasks significantly faster than residents in 4K HD group with comparable error scores. The time taken to complete the tasks on 2D HD were comparable between residents trained in 3D HD and 4K HD in two out of three tasks (p = 0.027, P = 0.115, p = 0.368 in task 1, 2 and 3 respectively). However, in two out of three tasks, residents trained on 3D HD committed significantly more errors than residents trained on 4K HD (p < 0.0001, p < 0.001 in task 1 and task 2 respectively). Skill acquired on 4K HD seems transferable to 2D HD environment. Participants trained in 3D HD made more errors while performing the tasks in 2D HD. It may be prudent to offer additional training on 2D HD to residents trained on 3D HD for safer laparoscopic surgical practice.

Cloud media video encoding: review and challenges

AbstractIn recent years, Internet traffic patterns have been changing. Most of the traffic demand by end users is multimedia, in particular, video streaming accounts for over 53%. This demand has led to improved network infrastructures and computing architectures to meet the challenges of delivering these multimedia services while maintaining an adequate quality of experience. Focusing on the preparation and adequacy of multimedia content for broadcasting, Cloud and Edge Computing infrastructures have been and will be crucial to offer high and ultra-high definition multimedia content in live, real-time, or video-on-demand scenarios. For these reasons, this review paper presents a detailed study of research papers related to encoding and transcoding techniques in cloud computing environments. It begins by discussing the evolution of streaming and the importance of the encoding process, with a focus on the latest streaming methods and codecs. Then, it examines the role of cloud systems in multimedia environments and provides details on the cloud infrastructure for media scenarios. After doing a systematic literature review, we have been able to find 49 valid papers that meet the requirements specified in the research questions. Each paper has been analyzed and classified according to several criteria, besides to inspect their relevance. To conclude this review, we have identified and elaborated on several challenges and open research issues associated with the development of video codecs optimized for diverse factors within both cloud and edge architectures. Additionally, we have discussed emerging challenges in designing new cloud/edge architectures aimed at more efficient delivery of media traffic. This involves investigating ways to improve the overall performance, reliability, and resource utilization of architectures that support the transmission of multimedia content over both cloud and edge computing environments ensuring a good quality of experience for the final user.

The effect of thermomechanical treatment on the electrodeposited Invar alloy for FMM

Fine metal masks (FMMs), which are applied to manufacture next-generation organic light-emitting diode (OLED) displays with ultra-high definition (UHD) or higher, must have thicknesses of <10 μm to eliminate shadow zones. To manufacture FMMs with a thickness of 10 μm or less, a bottom-up electroplating process must be applied. The minimum coefficient of thermal expansion (CTE) of the as-deposited electroplated Invar alloy is 4 ppm; subsequent thermal treatment can lead to a CTE of zero. However, sample conditions such as surface wrinkles and edge curls may appear during this thermal treatment process. The effect of varying treatment parameters, including pressure and temperature, on the shape of the electrodeposited Invar alloy is investigated in this study by performing a thermomechanical treatment that can regulate the ultrathin FMM shape. Depending on the Ni composition, the electrodeposited Invar alloy may exist as a singular α-BCC phase or a mixed γ-FCC phase during electrodeposition. During thermomechanical treatment, a phase transformation occurs from the electrodeposited α-BCC phase to the γ”-FCC phase, and wrinkles occur owing to uneven volume change. Additionally, curls are formed owing to CTE variations according to the ratio of phases from the electrodeposition surface to the final surface varies during the plating process. Based on these results, process conditions that facilitate shape control of ultra-thin electroplated FeNi alloys were proposed.

Performance Comparison of VVC, AV1, HEVC, and AVC for High Resolutions

Over the years, there has been growing interest in multimedia services, especially in the video domain, where firms and subscribers require higher resolutions, framerates, and sampling precision. This results in a huge amount of data that needs to be processed, stored, and transmitted. As a result, researchers face the challenge of developing new compression standards that can reduce the amount of data while maintaining the same quality. In this paper, the compression performance of the latest and most commonly used video codecs, namely H.266/VVC, AV1, H265/HEVC, and H.264/AVC was examined. The test set included seven sequences of various content at 8K, Ultra HD (UHD), and Full HD (FHD) resolutions, encoded to bitrates ranging from 1 to 15 Mbps for FHD and UHD resolutions and from 5 to 50 Mbps for 8K resolution. Objective quality metrics, such as peak signal-to-noise ratio (PSNR), the structural similarity index (SSIM), and video multi-method assessment fusion (VMAF) were used to measure codec performance. The results showed that H.266/VVC outperformed all other codecs, namely H.264/AVC, H.265/HEVC, and AV1, in terms of the Bjøntegaard delta (BD) model. The average bitrate savings were approximately 78% for H.266/VVC, 63% for AV1, and 53% for H.265/HEVC relative to H.264/AVC, 59% for H.266/VVC and 22% for AV1 compared to H.264/AVC, and 46% for H.266/VVC relative to AV1 (all for 8K resolution). The results also showed that codec performance varied depending on resolution, with higher resolutions showing greater efficiency for newly developed codecs, such as H.266/VVC and AV1. This confirms the fact that the H.266/VVC and AV1 codecs were primarily developed for videos at high resolutions, such as 8K and/or UHD.

UHD Database Focus on Smart Cities and Smart Transport

“Smart city” refers to a modern solution to organizing a city’s services, using cloud technologies to collect and evaluate large amounts of data, including data from camera systems. Smart city management covers several areas that can be implemented separately, but only their combination can realize the overall desired smart city function. One of the core areas of smart city automation is smart city transport. Transportation is a crucial system in any city, and this is why it needs to be monitored. The primary objective of this publication is to generate top-notch 4K UHD video sequences that are solely dedicated to showcasing smart cities and their transportation systems. The resulting comprehensive database will be made accessible to all professionals in the field, who can utilize it for extensive research purposes. Additionally, all the reference video sequences will be transcoded into various quality settings by altering critical parameters like the resolution, compression standard, and bit rate. The ultimate aim is to determine the best combination of video parameters and their respective settings based on the measured values. This in-depth evaluation will ensure that each video sequence is of the highest quality and provides an unparalleled experience for the service providers offering the service. The video sequences captured will be analyzed for quality assessments in smart cities or smart transport technologies. The database will also include objective and subjective ratings, along with information about the dynamics determined by spatial and temporal information. This will enable a comparison of the subjective evaluation of a selected sample of our respondents with the work of other researchers, who may evaluate it with a different sample of evaluators. The assumption of our future research is to predict the subjective quality based on the type of sequence determined by its dynamicity.

Quality Enhancement with Frame-wise DLCNN using High Efficiency Video Coding in 5G Networks

In the present situation, applications related to multimedia are discovered to be comfortable with the use of video. The number of end consumers who use video continues to rise every day. People are presently searching for videos with better quality among the ones that are currently available there. This results in the launch and dissemination of HD (high definition) videos. Ultra high-definition (UHD) videos are becoming more and more popular as a result of this advancement and need. However, as video communication keeps expanding, there is an upsurge in network traffic because of the limited bandwidth, especially among smart cities. Different advancement codecs have been suggested to deal with the data stream to overcome this hazardous circumstance. However, the fact that modern UHD videos have huge amounts of data makes the available codecs even more complicated. UHD videos can be processed with the latest improvement codec, H.265/High-efficiency video coding (HEVC). Nevertheless, it is impacted by increased power consumption and intricate calculations. Limitations in the codec's functionality confine its use to specific applications, preventing its application in wireless, mobile, or portable settings. Hence, this research concentrates on implementing frame-level quality enhancement through a deep learning network known as FQE-Net. The deep learning convolutional neural network (DLCNN) is specifically crafted to manage films with resolutions up to 16K. Its primary objectives include reducing complexity, minimizing artifacts, enhancing the efficiency of the HEVC codec, and compacting energy consumption. To achieve superior efficiency, it is imperative to replace the DWT transforms within the HEVC codec with a DLCNN model. Additionally, incorporating the Content Block Search Algorithm for Motion Estimation and Compensation, alongside filtering techniques like Sample Adaptive Filter and Deblocking Filter, becomes essential. The simulation results showed that the suggested FQE-Net performed better than the conventional techniques.

Synthetic method of pure-red emissive CsPbI3 under ambient conditions for quantum-dot light-emitting diode application

Perovskite quantum dots (PeQDs) are expected to be used in ultra-high-definition television (UHDTV) due to their excellent optical properties. However, pure-red emissive (λ EL: 620–650 nm) PeQD-based LEDs (PeLEDs) are required for UHDTV with single-halogen PeQDs synthesized under ambient conditions, which is important for practical use. Hence, we established a novel synthetic method to prepare PeQDs under ambient conditions via a different reaction from conventional methods. We successfully prepared PeQDs with pure-red emissivity λ PL: 631 nm and near-unity photoluminescence quantum yield. The PeLEDs with the PeQDs showed pure-red emission of 647 nm.

EMS: Erasure-Coded Multi-Source Streaming for UHD Videos Within Cloud Native 5G Networks

Ultra-High-Definition (UHD) videos have been getting increasing attention. However, existing video streaming solutions fail to deliver them due to the extremely high bandwidth requirement. The emerging cloud native 5G networks have opened up the possibility of enhancing UHD video quality by leveraging in-network video streaming. Unfortunately, the restricted storage and bandwidth of in-network servers could become the main bottleneck. To this end, we present <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math>${\sf EMS}$</tex-math></inline-formula> , a novel UHD video streaming framework, by integrating <underline xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E</u> rasure-coded storage with <underline xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">M</u> ulti-source <underline xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</u> treaming. We respectively introduce a deadline-aware and a latency-sensitive metric to indicate the service quality of video servers and advocate a federated learning paradigm for the adaptive service quality update, including a reinforcement learning based multi-server selection (i.e., user local training) and a global service quality aggregation. To facilitate user local training without sacrificing streaming Quality-of-Experience (QoE), we cast the multi-server selection associated with the restriction on the average number of selected servers per video chunk into two kinds of Multi-Armed Bandit (MAB) models in terms of the proposed service quality metrics. We design lightweight Upper Confidence Bound (UCB) based algorithms with a theoretical performance guarantee. We implement a prototype of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math>${\sf EMS}$</tex-math></inline-formula> , and extensive experiments confirm the superiority of the proposed algorithms.

Elastic Organic Crystals Exhibiting Amplified Spontaneous Emission Waveguides with Standard Red Chromaticity of the Rec.2020 Gamut.

The use of mechanically flexible molecular crystals as optical transuding media is demonstrated for a plethora of applications; however, the spectral peaks of optical outputs located mainly in the range of 400-600nm are insufficient for practical telecommunication and full-color display applications. Herein, two elastically bendable organic crystals are reported that show red emission of the rec.709 gamut under 365nm UV light irradiation yet generate rec.2020 gamut red optical waveguides and amplified spontaneous emissions when irradiated by a 355nm laser. Capitalizing on the extended π-conjugation and donor-acceptor character, as well as mechanical elasticity, these organic crystals exhibit flexible optical waveguides with Commission Internationale de L'Eclairage (CIE) coordinates of (0.70, 0.29), nearly identical to the red chromaticity of the rec.2020 gamut required for ultrahigh-definition (UHD) displays. Notably, one of the elastic crystals functions as a soft resonance cavity, resulting in amplified spontaneous emission waveguides with CIE coordinates of (0.71, 0.29) and the standard red chromaticity of the rec.2020 gamut, both in straight and bent states. This study presents a new avenue for the development of high-purity red-emissive crystalline materials to create all-organic, lightweight, and mechanically compliant optical telecommunication and UHD display devices.

QoE-Based Performance Comparison of AVC, HEVC, and VP9 on Mobile Devices with Additional Influencing Factors

While current video quality assessment research predominantly revolves around resolutions of 4 K and beyond, targeted at ultra high-definition (UHD) displays, effective video quality for mobile video streaming remains primarily within the range of 480 p to 1080 p. In this study, we conducted a comparative analysis of the quality of experience (QoE) for widely implemented video codecs on mobile devices, specifically Advanced Video Coding (AVC), its successor High-Efficiency Video Coding (HEVC), and Google’s VP9. Our choice of 720 p video sequences from a newly developed database, all with identical bitrates, aimed to maintain a manageable subjective assessment duration, capped at 35–40 min. To mimic real-time network conditions, we generated stimuli by streaming original video clips over a controlled emulated setup, subjecting them to eight different packet-loss scenarios. We evaluated the quality and structural similarity of the distorted video clips using objective metrics, including the Video Quality Metric (VQM), Peak Signal-to-Noise Ratio (PSNR), Video Multi-Method Assessment Fusion (VMAF), and Multi-Scale Structural Similarity Index (MS-SSIM). Subsequently, we collected subjective ratings through a custom mobile application developed for Android devices. Our findings revealed that VMAF accurately represented the degradation in video quality compared to other metrics. Moreover, in most cases, HEVC exhibited an advantage over both AVC and VP9 under low packet-loss scenarios. However, it is noteworthy that in our test cases, AVC outperformed HEVC and VP9 in scenarios with high packet loss, based on both subjective and objective assessments. Our observations further indicate that user preferences for the presented content contributed to video quality ratings, emphasizing the importance of additional factors that influence the perceived video quality of end users.

Divide-and-conquer-based RDO-free CU Partitioning for 8K Video Compression

8K (7689×4320) ultra-high definition (UHD) videos are growing popular with the improvement of human visual experience demand. Therefore, the compression of 8K UHD videos has become a top priority in the third-generation audio video coding standard (AVS3). However, as an important part of the coding standard promotion, the real-time hardware implementation for AVS3-based 8K UHD video intra coding is severely hindered, especially in the coding unit (CU) partition stage. To break through the limitation, this article proposes a divide-and-conquer-based rate-distortion-optimization-free (RDO-free) CU partitioning algorithm for efficient hardware implementation. Aimed at the complex CU partition in AVS3, we separately design a lightweight optimization for original partitioning rules to improve division efficiency and a decision tree-based RDO-free CU decision framework to eliminate the latency caused by the waiting for rate-distortion cost calculation in RDO strategy. Afterward, a divide-and-conquer-based hardware-friendly gradient difference calculating approach is devised to accelerate the learning feature extracting speed. To ensure that the proposed algorithm is sufficient to support the real-time CU partition for 8K videos, we also develop a hardware architecture based on FPGA. Experimental results illustrate that the software coding performance of our algorithm is significantly ahead of the efficient implementation uAVS3e for AVS3 and the reference software HM-16.20 for High Efficiency Video Coding (HEVC), even though there is 9.96% loss on BD-Rate Y. Considering its importance for the hardware implementation of AVS3-based 8K real-time encoder, the coding loss is acceptable. Moreover, the hardware simulation results on VU440 FPGA with Vivado 2019 show that our algorithm can support 61.12 frames per second (fps) CU partition for 8K UHD videos with only 0.00%, 0.00%, 1.01%, and 7.78% consumption of BRAM_18K, DSP48E, FF, and LUT, respectively. Additionally, with dual-path parallelism, 122.24 fps also can be implemented with controllable resource utilization, which achieves the state-of-the-art performance.

Enhancing spatial navigation skills in mild cognitive impairment patients: a usability study of a new version of ANTaging software.

Mild Cognitive Impairment (MCI) often presents challenges related to spatial navigation and retention of spatial information. Navigating space involves intricate integration of bodily and environmental cues. Spatial memory is dependent on two distinct frame of reference systems for organizing this information: egocentric and allocentric frames of reference. Virtual Reality (VR) has emerged as a promising technology for enhancing spatial navigation skills and spatial memory by facilitating the manipulation of bodily, environmental, and cognitive cues. This usability study was based on a fully within-subjects design in which seven MCI patients underwent two kinds of VR conditions: participants were required to complete the ANTaging demo both in Oculus Rift S (immersive condition) and in Samsung UHD 4K monitor (semi-immersive condition). Participants were seated and they had to use a foot-motion pad to navigate and explore the environment to collect and relocate some objects in the virtual environment. Post-interaction, users provided feedback on their experiences. Additionally, usability, potential side effects, data analysis feasibility, and user preferences with immersive and semi-immersive technologies were assessed through questionnaires. Results indicated higher usability ratings for the semi-immersive setup, with fewer negative effects reported compared to the immersive counterpart. According to qualitative analyses of the interviews, patients do seem to like both VR apparatuses even though the semi-immersive condition was perceived as the most suitable choice because of the size of the screen. Patients generally found it difficult to remember object locations. Participants expressed the need for more practice with the foot-motion pad, despite an overall positive experience. They generally would like to use this system to improve their memory. Identifying these key aspects was crucial for refining the system before the upcoming clinical trial. This study sheds light on the potential of semi-immersive VR in aiding individuals with MCI, paving the way for enhanced spatial navigation interventions.

Strongly-confined colloidal lead-halide perovskite quantum dots: from synthesis to applications.

Colloidal semiconductor nanocrystals enable the realization and exploitation of quantum phenomena in a controlled manner, and can be scaled up for commercial uses. These materials have become important for a wide range of applications, from ultrahigh definition displays, to solar cells, quantum computing, bioimaging, optical communications, and many more. Over the last decade, lead-halide perovskite nanocrystals have rapidly gained prominence as efficient semiconductors. Although the majority of studies have focused on large nanocrystals in the weak- to intermediate-confinement regime, quantum dots (QDs) in the strongly-confined regime (with sizes smaller than the Bohr diameter, which ranges from 4-12 nm for lead-halide perovskites) offer unique opportunities, including polarized light emission and color-pure, stable luminescence in the region that is unattainable by perovskites with single-halide compositions. In this tutorial review, we bring together the latest insights into this emerging and rapidly growing area, focusing on the synthesis, steady-state optical properties (including exciton fine-structure splitting), and transient kinetics (including hot carrier cooling) of strongly-confined perovskite QDs. We also discuss recent advances in their applications, including single photon emission for quantum technologies, as well as light-emitting diodes. We finish with our perspectives on future challenges and opportunities for strongly-confined QDs, particularly around improving the control over monodispersity and stability, important fundamental questions on the photophysics, and paths forward to improve the performance of perovskite QDs in light-emitting diodes.

PET/CT Reconstruction and Its Impact on [Measures of] Metabolic Tumor Volume

In oncological imaging, the use of metabolic tumor volume (MTV) for further prognostic differentiation and the development of risk adapted strategies appears promising. The aim of this analysis was to evaluate ultra-high definition (UHD) and ordered subset expectation maximization (OSEM) PET/CT reconstructions for their potential impact on different methods of MTV measurement. We analyzed positron emission tomography combined with computed tomography (PET/CT) scans of 40 Hodgkin lymphoma patients before first-line treatment who had undergone fluorodeoxyglucose (FDG) PET/CT. The MTVs were determined taking an SUV of 4.0 (MTV4.0) as a fixed threshold or 41% of the single hottest voxel (MTV41%) as an adaptive threshold for automated lymphoma delineation in both UHD and OSEM reconstructions. We then compared the absolute and relative differences between MTV4.0 and MTV41% in UHD and OSEM reconstructions. The relative distribution of MTV4.0 and MTV41% in relation to the reconstruction method applied was recorded and respective differences were tested for statistical significance using the paired sample t-test. A comparison of MTV4.0 and MTV41% showed smaller relative and absolute differences in MTV between different reconstruction settings for the MTV4.0 method. Conversely, the absolute as well as the relative differences between MTVs obtained from different reconstructions settings were significantly greater when the MTV41% method was applied (p<0001). MTV4.0 brings higher robustness between different reconstruction settings, while with MTV41% the deviation between volumes obtained with different reconstruction settings is greater. For clinical routine and for multicenter settings, the MTV4.0 therefore appears most promising.

A Routing Algorithm Based on Software-Defined Computing First Network

With the continuous development of mobile Internet technology, new services and applications appear, such as AR/VR, Internet of Vehicles, and Ultra HD Video. They not only require higher network bandwidth resources but also need more computing resources to ensure normal operation and user experience. As a new network technology, computing first network promotes the deep integration of distributed computing resources and networks to make efficient use of these resources. This paper proposes a computing power routing algorithm based on software-defined computing first network (SD-CFN) architecture. It comprehensively considers computing resources and available bandwidth resources of network links. Experimental results show that compared with the nearby scheduling strategy, the proposed computing power routing algorithm can better allocate computing resources to services. Moreover, it can improve the utilization rate of computing resources and provide optimal bandwidth resources in the process of service transmission.

#61 : Frugal Exoscope: A Potential Option for Microsurgery and Training Program in Male Infertility in the Context of Emerging Markets

Background and Aims: Conventional microscopes and exoscopes currently play pivotal roles in the microsurgery or training of male infertility. However, they are expensive and unaffordable in low resource settings which limits training or application of advanced methods. The study aimed to introduce a new, low–cost exoscope system and evaluate its frugal innovation. Method: Using animal models, we evaluated a new frugal exoscope system (called DKTA) in experimental microsurgery of vas deferens repair. Five experts in male infertility surgery undertook an anonymous survey to elucidate their experience with DKTA system use. Three crucial criteria (i.e., substantial cost reduction, concentration on core functionalities, optimised performance level) were evaluated to determine whether the DKTA is effective as frugal innovation. The survey used a 5-point Likert scaling of responses to eight statements investigating surgical, ergonomic, and educational aspects. Results: The DKTA system, including an optical microscope and ultrahigh definition camera (4K), was an exoscope placed between 20–40 cm from the surgical field. It was held in position with a camera support arm on casters and connected to a 65-inches smart TV. DKTA system met the three crucial criteria of frugal innovation, including substantial cost reduction, concentration on core functionalities, and optimised performance level. Five male infertility microsurgeons reported positive evaluations of the DKTA system (use modal scores) when performing experimental vasovasostomy. Conclusions: DKTA system, a frugal innovation, has a valuable contribution to the training programme and performance of male infertility microsurgery in low–resource settings. Acknowledgements: We want to send special thanks to the Centre for Training and Scientific Research staff, Tam Anh General Hospital for their logistics support.

Cinephilia, take three?: Availability, reliability, and disenchantment in the streaming era

This article proposes a modified reading of Thomas Elsaesser’s theories of cinephilia, taking into account the new viewing practices established by the rise of online media streaming. Elsaesser characterised early film culture (labelled as ‘take one’) as rooted in celluloid and marked by a longing to view films that were not always easily available. By contrast, his characterisation of the later ‘take two’ era is one in which each new distribution technology (television, VHS, and so on) promises greater abundance and convenience, to the point where this new generation of cinephiles – in response to the widespread success of DVD – were perceived as having to deal with the ‘anachronisms generated by total availability’. Amanda D. Lotz argues that streaming services appear to provide an extension of the ‘take two’ ideal, offering assurances of ‘ availability (on-demand libraries with many choices) and reliability (you don’t have to watch it now or it’s gone)’. I suggest, however, that the underlying impermanence of streaming has prompted fears related to both access and ownership, marking a break from the expectations surrounding the DVD (as well as its successors Blu-ray and 4K Ultra HD). The impact of content migration – fracturing access between a greater number of paid platforms – and particularly content delisting – the outright removal of access to a given text – can place certain works in a form of limbo. This article proposes the dawn of a new generation of cinephilia – a potential take three – marked by a newfound concern of ephemerality, albeit much more potential and localised than the widespread unavailability of the take one era. In essence, then, take three wrestles with the anachronisms of loss in a media landscape that, in many other ways, offers unprecedented levels of access to film and television content.

Is the Brainstem Activation Different Between Healthy Young Male and Female Volunteers at Initiation of Voiding? A High Definition 7-Tesla Magnetic Resonance Imaging Study.

Assessing brainstem function in humans through typical neuroimaging modalities has been challenging. Our objective was to evaluate brain and brainstem activation patterns during initiation of voiding in healthy males and females utilizing a 7 Tesla magnetic resonance imaging (MRI) scanner and a noninvasive brain-bladder functional MRI (fMRI) protocol. Twenty healthy adult volunteers (10 males and 10 females) with no history of urinary symptoms were recruited. Each volunteer underwent a clinic uroflow and postvoid residual assessment and was asked to consume water prior to entering the scanner. Anatomical and diffusion tensor images were obtained first, followed by a blood oxygenation level dependent (BOLD) resting-state fMRI (rs-fMRI) during the empty bladder. Subjects indicated when they felt the urge to void, and a full bladder rs-fMRI was obtained. Once completed, the subjects began 5 voiding cycles, where the first 7.5 seconds of each voiding cycle was identified as "initiation of voiding." BOLD activation maps were generated, and regions of interests with a t-value greater than 2.1 were deemed statistically significant. We present 5 distinct regions within the periaqueductal gray (PAG) and pontine micturition center (PMC) with statistically significant activation associated with an initiation of voiding in both men and women, 3 within the PAG and 2 within the PMC. Several additional areas in the brain also demonstrated activation as well. When comparing males to females, there was an overall lower BOLD activation seen in females throughout all regions, with the exception of the caudate lobe. Our study effectively defines regions within the PAG and PMC involved in initiation of voiding in healthy volunteers. To our knowledge, this is the first study investigating differences between male and female brainstem activation utilizing an ultra-high definition 7T MRI.

Comparative study on deep-learning-based leather surface defect identification

Detecting leather surface defects has become an important subject in industrial inspections and attracted significant attention as a challenging task. Traditional image processing techniques struggle with the detection of leather surface defects with a variety of shapes, sizes, backgrounds, and noise. Deep learning is a promising solution to this problem. This work focuses on the comparative study of 26 classical deep learning models in the field of leather surface defect type recognition. That aims to lay a foundation for the design and development of new schemes for leather defect inspection. Based on tanned leather from an enterprise, eight types of leather surface defects (cavities, pinholes, scratches, rotten surfaces, growth lines, healing wounds, folds, and bacterial wounds) were collected using an ultra-high definition whole leather imaging device. Two challenging datasets with various shapes, sizes, and colours were constructed. Extensive experimental evaluations were conducted. The deep learning model can achieve more than 95% accuracy when the defect imaging is ideal and limited. In case that the shapes, sizes, and colour of the above eight defects keep diverse, Densenet169 performed the best with a recognition accuracy of 72.5%, and ShuffleNet model with the worst performance reached 64.3%. Systematic in-depth experimental evaluation shows that deep learning models are promising in the field of leather surface defect detection, however, challenges remain.

Frontier Molecular Orbital Engineering: Constructing Highly Efficient Narrowband Organic Electroluminescent Materials.

It is of great strategic significance to develop highly efficient narrowband organic electroluminescent materials that can be utilized to manufacture ultra-high-definition (UHD) displays and meet or approach the requirements of Broadcast Television 2020 (B.T.2020) color gamut standards. This motif poses challenges for molecular design and synthesis, especially for developing generality, diversity, scalability, and robustness of molecular structures. The emergence of multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters has ingeniously solved the problems and demonstrated bright application prospects in the field of UHD displays, sparking a research boom. This Minireview summarizes the research endeavors of narrowband organic electroluminescent materials, with emphasis on the tremendous contribution of frontier molecular orbital engineering (FMOE) strategy. It combines the outstanding advantages of MR framework and donor-acceptor (D-A) structure, and can achieve red-shift and narrowband emission simultaneously, which is of great significance in the development of long-wavelength narrowband emitters with emission maxima especially exceeding 500 nm. We hope that this Minireview would provide some inspiration for what could transpire in the future.