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Metasurfaces have enabled a plethora of emerging functions within an ultrathin dimension, paving way towards flat and highly integrated photonic devices. Despite the rapid progress in this area, simultaneous realization of reconfigurability, high efficiency, and full control over the phase and amplitude of scattered light is posing a great challenge. Here, we try to tackle this challenge by introducing the concept of a reprogrammable hologram based on 1-bit coding metasurfaces. The state of each unit cell of the coding metasurface can be switched between ‘1’ and ‘0’ by electrically controlling the loaded diodes. Our proof-of-concept experiments show that multiple desired holographic images can be realized in real time with only a single coding metasurface. The proposed reprogrammable hologram may be a key in enabling future intelligent devices with reconfigurable and programmable functionalities that may lead to advances in a variety of applications such as microscopy, display, security, data storage, and information processing. Realizing metasurfaces with reconfigurability, high efficiency, and control over phase and amplitude is a challenge. Here, Li et al. introduce a reprogrammable hologram based on a 1-bit coding metasurface, where the state of each unit cell of the coding metasurface can be switched electrically.

To help doctors and patients evaluate lumbar intervertebral disc degeneration (IVDD) accurately and efficiently, we propose a segmentation network and a quantitation method for IVDD from T2MRI. A semantic segmentation network (BianqueNet) composed of three innovative modules achieves high-precision segmentation of IVDD-related regions. A quantitative method is used to calculate the signal intensity and geometric features of IVDD. Manual measurements have excellent agreement with automatic calculations, but the latter have better repeatability and efficiency. We investigate the relationship between IVDD parameters and demographic information (age, gender, position and IVDD grade) in a large population. Considering these parameters present strong correlation with IVDD grade, we establish a quantitative criterion for IVDD. This fully automated quantitation system for IVDD may provide more precise information for clinical practice, clinical trials, and mechanism investigation. It also would increase the number of patients that can be monitored. Globally, as a major public health problem, low back pain has been the leading cause of disability worldwide for the past 30 years. Here, the authors propose a segmentation network and a quantitative method lumbar intervertebral disc degeneration assessment.

Aortic aneurysm (AA) and aortic dissection (AD) are major life-threatening diseases around the world. AA is a localized or diffuse dilation of the aorta, while AD is the separation of the layers creating a false lumen within the aortic wall. Fluoroquinolones (FQ) remain one of the most important kind of antibiotics and have a wider clinical use and broad antibacterial spectrum. FQ were also reported to treat infected AA. The most common adverse events (AEs) of FQ are mild and reversible, like headaches, diarrhea and nausea. Due to FQ-related serious AEs, such as tendonitis and tendon rupture, chondrotoxicity, or retinal detachment, QT-prolongation and dysglycemia, the United States Food and Drug Administration (FDA) issued a black box warning for FQ for systemic use in 2016 and updated warnings for FQ several times since then. Of note, in December 2018, FDA issued several “black box warnings” against FQ with the latest safety announcement warning about an increased risk of ruptures in the aorta blood vessel in certain patients. Recently, many studies have indicated an association between FQ and an increase risk of AA and AD. However, the exact mechanism of FQ-induced AA/AD remains unclear. This review aims to highlight the latest research progress of the alarming association between FQ and AA/AD. Moreover, molecular mechanisms of FQ in increasing risk of AA and AD are explored. Hopefully, this review can provide novel insights into FQ-increased the risk of AA/AD and a starting place for stewardship interventions.

Bentonite pellets are recognized as good buffer/backfill materials for sealing technological voids in high-level radioactive waste (HLW) repository. Compared to that of a traditional compacted bentonite block, one of the most important particularities of this material is the initially discrete pellets and the inevitable heterogeneous porosity formed, leading to a distinctive water retention behaviour. In this paper, water retention and mercury intrusion porosimetry (MIP) tests were conducted on pellet mixture (constant volume), single pellet (free swelling) and compacted block (constant volume) of GMZ bentonite, water retention properties and pore structure evolutions of the specimens were comparatively investigated. Results show that the water retention properties of the three specimens are almost similar to each other in the high suction range (> 10 MPa), while the water retention capacity of pellet mixture is lower than those of the compacted block and single pellet in the low suction range (< 10 MPa). Based on the capillary water retention theory (the Young–Laplace equation), a new concept ‘saturated void ratio’ that was positively related to water content and dependent on pore size distribution of the specimen was defined. Then, according to the product of saturated void ratio and water density in saturated void, differences of water retention properties for the three specimens at low suctions were explained. Meanwhile, MIP tests indicate that as suction decreases, the micro- and macrovoid ratios of pellet mixture and compacted block decrease as the mesovoid ratio increases, while all the void ratios of single pellets increase. This could be explained that upon wetting, water is successively adsorbed into the inter-layer, inter-particle and inter-pellet voids, leading to the subdivision of particles and swelling of aggregates and pellets. Under constant volume condition, aggregates and pellets tend to swell and fill into the inter-aggregates or inter-pellets voids. While under free swelling condition, the particles and aggregates in a single pellet tend to swell outward rather than squeezing into the inter-aggregate voids, leading to the expansion of the pores and even formation of cracks. Results including the effects of initial conditions (initial dry density and fabric) and constraint conditions (constant volume or free swelling) on the water retention capacity and pore structure evolution reached in this work are of great importance in designing of engineering barrier systems for the HLW repository.

The photoelectrochemical (PEC) conversion of organic small molecules offers a dual benefit of synthesizing value-added chemicals and concurrently producing hydrogen (H2). Ethylene glycol, with its dual hydroxyl groups, stands out as a versatile organic substrate capable of yielding various C1 and C2 chemicals. In this study, we demonstrate that pH modulation markedly enhances the photocurrent of BiVO4 photoanodes, thus facilitating the efficient oxidation of ethylene glycol while simultaneously generating H2. Our findings reveal that in a pH = 1 ethylene glycol solution, the photocurrent density at 1.23 V vs. RHE can attain an impressive 7.1 mA cm−2, significantly surpassing the outputs in neutral and highly alkaline environments. The increase in photocurrent is attributed to the augmented adsorption of ethylene glycol on BiVO4 under acidic conditions, which in turn elevates the activity of the oxidation reaction, culminating in the maximal production of formic acid. This investigation sheds light on the pivotal role of electrolyte pH in the PEC oxidation process and underscores the potential of the PEC strategy for biomass valorization into value-added products alongside H2 fuel generation.

The fusion of electromagnetic (EM) waves and information theory in wireless and waveguide communication technologies has enjoyed a remarkable revival during the last few years. In particular, unlike traditional transceiver systems, the recently proposed information metasurface system directly links the controllable binary array sources with the scattered EM waves, making the combination of EM and information theories highly desirable and natural. Moreover, a traditional linear channel matrix cannot be directly used for such scattering reconfigurability enabled communication system, making the information characterization of such system a great challenge. In this paper, EM information characteristics of a direct digital modulation (DDM) system enabled by programmable information metasurface, also known as reconfigurable intelligent surface (RIS), are analyzed, in which RIS is used as a modulator of the illuminating field, while the scattered far-field amplitudes are measured and effectively treated as the received quantities. The posterior probability for a specific source coding pattern, conditioned over a given measured scattering fields, is obtained through the Bayesian analysis technique, from which the average mutual information (AMI) is obtained to estimate the RIS observation capability along any particular direction. The averaged receiver mutual information (ARMI) is then introduced to characterize the generated field correlation structures along different observation directions. Based on ARMI, the joint observation capability is also analyzed. Furthermore, the suggested techniques are employed in a noisy environment, and a code selection scheme is put forth to achieve efficient information transmission. The proposed configuration is validated through a simulated experiment. As a comprehensive evaluation of the system's performance, the channel capacity of the system is derived, and a set of relevant influencing factors are identified and analyzed from four different perspectives: 1) the observation direction, 2) the size of RIS, 3) potential joint observations in multiple directions, and 4) the noise level. The proposed method, together with the various related performance measure metrics introduced therein, are expected to provide the research community with guidelines for analyzing and designing the current and future RIS-based communication systems, which can also be extended to other aspects in the growing field of the EM information theory.

Background Although the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ), Numerical Pain Rating Scale (NPRS), Oswestry Disability Index (ODI), Roland Morris Disability Questionnaire (RMDQ), and Short Form 36 Health Survey (SF-36) has shown a preferable psychometric properties in patients with low back pain (LBP), but no study has yet determined these in conservative treatment of patients with lumbar disc herniation (LDH). Thus the current study aimed to compare those scales in LDH patients receiving conservative treatment to select the better option to assess the severity of disease. Methods LDH patients were invited to complete the JOABPEQ, NPRS, ODI, RMDQ, and SF-36 twice. The internal consistency was evaluated by the Cronbach’s α. Test-retest reliability was tested by the intraclass correlation coefficient (ICC). The relationships of these scales were evaluated by the Pearson correlation coefficients ( r ). The responsiveness was operationalised using the receiver operating characteristic (ROC) curve, as well as the comparison of smallest detectable change (SDC), minimum important change (MIC). Results A total of 353 LDH patients were enrolled. Four subscales of the Chinese JOABPEQ were over 0.70, then the ICCs for the test-retest reliability were over 0.75. For functional status, remarked negative correlations could be seen between JOABPEQ Q2-Q4 and ODI, as well as RMDQ ( r  = − 0.634 to − 0.752). For general health status, remarkable positive correlations could also be seen between Q5 Mental health and SF-36 PCS ( r  = 0.724) as well as SF-36 MCS ( r  = 0.736). Besides, the area under of the curves (AUC) of the JOABPEQ ranged from 0.743 to 0.827, indicating acceptale responsiveness, as well as the NPRS, ODI, and RMDQ. Conclusion NPRS, and ODI or RMDQ is recommended in studies related to LDH patients, while if the quality of life also is needed to observe, the NPRS, and JOABPEQ would be more appropriate rather than SF-36.

Background This study aimed to identify and characterize the sedentary behavior (SED) and breaks accumulation patterns of children and adolescents and investigate the associations of these derived patterns with adiposity indicators. Methods A total of 348 children and 562 adolescents from China participated in this study. Accelerometers were used to measure the bouts of SED and breaks. Adiposity indicators included body mass index (BMI) z-score, fat mass percentage (FM%), and fat mass index (FMI). Latent profile analysis was used to identify the SED and breaks accumulation patterns on the basis of 11 compositions of SED bouts and breaks. Mixed-effects multivariable linear regression models were used to analyze the associations of accumulation patterns with adiposity indicators. Results Four accumulation patterns were identified in children: “prolonged sitters” ( N  = 77, 22.1%), “shortened sitters” ( N  = 90, 25.9%), “LPA breakers” ( N  = 69, 19.8%), and “MVPA breakers”( N  = 112, 32.2%). “MVPA breakers” had significantly lower BMI z-score, FM%, and FMI than “prolonged sitters.” No significant differences in adiposity indicators were observed among the other three patterns. In adolescents, “prolonged sitters” ( N  = 250, 44.5%), “moderate sitters” ( N  = 211, 37.5%), and “breakers” ( N  = 101, 18.0%) were identified. “Breakers” had the lowest BMI z-score, FM%, and FMI among the three groups, followed by “moderate sitters” and “prolonged sitters.” Conclusion Different accumulation patterns of SED and breaks were identified for children and adolescents in China. Among them, “MVPA breakers” and “Breakers” are most beneficial to maintain a normal weight status. Health promotion efforts could consider increasing MVPA and decreasing SED time for children and restricting SED to at least 30 min for adolescents to improve their adiposity indicators.