Real-time and continuous monitoring of nucleic acid biomarkers with wearable devices holds potential for personal health management, especially in the context of pandemic surveillance or intensive ...care unit disease. However, achieving high sensitivity and long-term stability remains challenging. Here, we report a tetrahedral nanostructure-based Natronobacterium gregoryi Argonaute (NgAgo) for long-term stable monitoring of ultratrace unamplified nucleic acids (cell-free DNAs and RNAs) in vivo for sepsis on wearable device. This integrated wireless wearable consists of a flexible circuit board, a microneedle biosensor, and a stretchable epidermis patch with enrichment capability. We comprehensively investigate the recognition mechanism of nucleic acids by NgAgo/guide DNA and signal transformation within the Debye distance. In vivo experiments demonstrate the suitability for real-time monitoring of cell-free DNA and RNA with a sensitivity of 0.3 fM up to 14 days. These results provide a strategy for highly sensitive molecular recognition in vivo and for on-body detection of nucleic acid.
Collagen plays an important role in the formation of extracellular matrix (ECM) and development/migration of cells and tissues. Here we report the preparation of collagen and collagen hydrogel from ...the skin of tilapia and an evaluation of their potential as a wound dressing for the treatment of refractory wounds. The acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were extracted and characterized using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), differential scanning calorimetry (DSC), circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR) analysis. Both ASC and PSC belong to type I collagen and have a complete triple helix structure, but PSC shows lower molecular weight and thermal stability, and has the inherent low antigenicity. Therefore, PSC was selected to prepare biomedical hydrogels using its self-aggregating properties. Rheological characterization showed that the mechanical strength of the hydrogels increased as the PSC content increased. Scanning electron microscope (SEM) analysis indicated that hydrogels could form a regular network structure at a suitable PSC content. Cytotoxicity experiments confirmed that hydrogels with different PSC content showed no significant toxicity to fibroblasts. Skin repair experiments and pathological analysis showed that the collagen hydrogels wound dressing could significantly accelerate the healing of deep second-degree burn wounds and the generation of new skin appendages, which can be used for treatment of various refractory wounds.
In this paper, we consider a two-channel multiple-input multiple-output passive detection problem, in which there is a surveillance array and a reference array. The reference array is known to carry ...a linear combination of broadband noise and a subspace signal of known dimension, but unknown basis. The question is whether the surveillance channel carries a linear combination of broadband noise and a subspace signal of the same dimension, but unknown basis, which is correlated with the subspace signal in the reference channel. We consider a second-order detection problem where these subspace signals are structured by an unknown, but common, p-dimensional random vector of symbols transmitted from sources of opportunity, and then received through unknown M × p matrices at each of the M-element arrays. The noises in each channel have spatial correlation models ranging from arbitrarily correlated to independent with identical variances. We provide a unified framework to derive the generalized likelihood ratio test for these different noise models. In the most general case of arbitrary noise covariance matrices, the test statistic is a monotone function of canonical correlations between the reference and surveillance channels.
Abstract The global spread of COVID-19 has profoundly affected health and economies, highlighting the need for precise epidemic trend predictions for effective interventions. In this study, we used ...infectious disease models to simulate and predict the trajectory of COVID-19. An SEIR (susceptible, exposed, infected, removed) model was established using Wuhan data to reflect the pandemic. We then trained a genetic algorithm-based SEIR (GA-SEIR) model using data from a specific U.S. region and focused on individual susceptibility and infection dynamics. By integrating socio-psychological factors, we achieved a significant enhancement to the GA-SEIR model, leading to the development of an optimized version. This refined GA-SEIR model significantly improved our ability to simulate the spread and control of the epidemic and to effectively track trends. Remarkably, it successfully predicted the resurgence of COVID-19 in mainland China in April 2023, demonstrating its robustness and reliability. The refined GA-SEIR model provides crucial insights for public health authorities, enabling them to design and implement proactive strategies for outbreak containment and mitigation. Its substantial contributions to epidemic modelling and public health planning are invaluable, particularly in managing and controlling respiratory infectious diseases such as COVID-19.
The demand forecasting plays a crucial role in the predictive physical and virtualized network management in cellular networks, which can effectively reduce both the capital and operational ...expenditures by fully exploiting the network infrastructure. In this paper, we study the per-cell demand forecasting in cellular networks. The success of demand forecasting relies on the effective modeling of both the spatial and temporal aspects of the per-cell demand time series. However, the main challenge of the spatial relevancy modeling in the per-cell demand forecasting is the irregular spatial distribution of cells in a network, where applying grid-based models (e.g., convolutional neural networks) would lead to degradation of spatial granularity. In this paper, we propose to model the spatial relevancy among cells by a dependency graph based on spatial distances among cells without the loss of spatial granularity. Such spatial distance-based graph modeling is confirmed by the spatiotemporal analysis via semivariogram, which suggests that the relevancy between any two cells declines as their spatial distance increases. Hence, the graph convolutional networks and long short-term memory (LSTM) from deep learning are employed to model the spatial and temporal aspects, respectively. In addition, the deep graph-sequence model, graph convolutional LSTM, is further employed to simultaneously characterize both the spatial and temporal aspects of mobile demand forecasting. Experiments demonstrate that our proposed graph-sequence demand forecasting model could achieve a superior forecasting performance compared with the other two proposed models as well as the traditional auto regression integrated moving average time series model.
Fluorinated carbon (CF
), a thriving member of the carbonaceous derivative, possesses various excellent properties of chemically stable, tunable bandgap, good thermal conductivity and stability, and ...super-hydrophobic due to its unique structures and polar C-F bonding. Herein, we present a brief review of the recent development of fluorinated carbon materials in terms of structures, properties and preparation techniques. Meanwhile, the applications in energy conversions and storage devices, biomedicines, gas sensors, electronic devices, and microwave absorption devices are also presented. The fluorinated carbon contains various types of C-F bonds including ionic, semi-ionic and covalent C-F, C-F
, C-F
bonds with tunable F/C ratios. The controllable designing of C-F bonding and F/C ratios play a key role to optimize the properties of fluorinated carbon materials. Until now, the potential issues and future opportunities of fluorinated carbon are proposed. The present review will provide a direction for tuning C-F bonding and F/C ratios, developing a safe and efficient fluorination method and popularizing the applications of fluorinated carbon materials.
Fracture-initiation pressure (FIP) is closely related to lost circulation and hydraulic fracturing. However, conventional prediction models often treat formation rock as an isotropic medium, ignoring ...the anisotropy of rock materials, particularly, the anisotropy of tensile strength. Therefore, a universal FIP model was proposed for inclined well in transversely isotropic formations, and the combined effects of both anisotropic elasticity and tensile strength were taken into account. The proposed model was verified by indoor experiments, and the predicted FIPs of isotropic and anisotropic models were compared. Finally, the influencing factors of FIP were investigated. The results indicated that compared with the experimental results, the present model is more consistent than traditional models, and the deviation factor is concentrated between 0.8 and 1.4. Compared with the traditional isotropic model, the maximum differences of the elastic anisotropic model, strength anisotropic model, and the present model are 0.059 g/cm3, 0.262 g/cm3, 0.258 g/cm3, respectively. The dip direction has almost no effect on the FIP at a low dip angle, while it has a significant effect at a high dip angle. The FIP is the minimum when the dip direction is parallel to the azimuth of wellbore, while it is the maximum when the dip direction is perpendicular to the azimuth of wellbore. With the increase of anisotropy index, the influence of elastic anisotropy and strength anisotropy is enhanced, and the maximum difference is 0.31 g/cm3 and 0.33 g/cm3 respectively; while the Poisson's ratio only has a small effect, and the maximum difference is only 0.256 g/cm3. The spatial distribution parameter (Ω0) directly affects the variation trend of tensile strength, too high a Ω0 may overestimate the FIP, while too low a Ω0 may underestimate the FIP. The present model and analysis results can provide theoretical guidance for lost circulation prevention and hydraulic fracturing optimization.
Medical security support for rehabilitation therapy in China is different from that in other countries. We investigated whether the discharge plan to continue rehabilitation therapy in tertiary ...hospitals for patients after traumatic spinal cord injury (TSCI) was influenced by payment sources or other conditions. This was a cross-sectional, observational study. Information was collected on the general condition, caregiver, types of payment sources for continued rehabilitation, American Spinal Injury Association Impairment Scale (AIS) scores, and discharge plans. In total, 135 patients with TSCI (107 male, mean age 41.00 ± 13.73 years, mean spinal cord injury duration 238.43 ± 345.54 days) were enrolled. Medical insurance (43%) and out-of-pocket payments (27.4%) were the primary payment sources. Although most patients were beyond the acute phase, 40% continued rehabilitation therapy at other tertiary hospitals. The caregiver, payment sources, injury level, AIS level, and complete urinary tract infection (UTI) were different due to discharge plans (
> .05). Patients seemingly consider a higher AIS level and co-UTI as the requirement for tertiary hospital therapy. In non-medical insurance payment source patients, the discharge plan also differed due to the AIS level and co-UTI (
> .05). However, in medical insurance patients, the discharge plan differed only in terms of TSCI duration (
> .05). The restricted duration of medical coverage restricted the continuation of rehabilitation therapy and influenced the discharge plan of most patients with TSCI.
Abstract The moiré potential serves as a periodic quantum confinement for optically generated excitons, creating spatially ordered zero-dimensional quantum systems. However, a broad emission spectrum ...resulting from inhomogeneity among moiré potentials hinders the investigation of their intrinsic properties. In this study, we demonstrated a method for the optical observation of quantum coherence and interference of a single moiré exciton in a twisted semiconducting heterobilayer beyond the diffraction limit of light. We observed a single and sharp photoluminescence peak from a single moiré exciton following nanofabrication. Our findings revealed the extended duration of quantum coherence in a single moiré exciton, persisting beyond 10 ps, and an accelerated decoherence process with increasing temperature and excitation power density. Moreover, quantum interference experiments revealed the coupling between moiré excitons in different moiré potential minima. The observed quantum coherence and interference of moiré exciton will facilitate potential applications of moiré quantum systems in quantum technologies.
Brazilian disc (BD) testing is a typical method for measuring the indirect tensile strength of rock materials. Both experimental and theoretical studies involving BD testing of anisotropic rocks ...typically focus on the influence of the 2D bedding effect, where a specimen is parallel to the bedding planes, whereas the influence of the 3D bedding effect combining both the orientation and loading angle has rarely been investigated. Therefore, in this study, BD tests considering the 3D bedding effect were conducted on layered Longmaxi shale, and 3D BD models of layered shale were established using 3D globally embedded cohesive elements with zero thickness. The numerical results were compared to testing results. The 3D BD numerical model was then applied to simulate Asan gneiss and Silurian silty slate to verify the applicability. Finally, the influence of the 3D bedding effect on both the apparent tensile strength (ATS) and failure modes was analyzed. We also considered the influence of the spacing of bedding planes and bedding strength. The results indicated that the numerical results for both the ATS and failure modes were in good agreement with the test results with a maximum error of 17.8% for the ATS. The applicability of the developed 3D BD numerical model to different layered rocks was confirmed by the numerical results for both Asan gneiss and Silurian silty slate. Strong dependencies of the ATS and failure modes on both the orientation (α) and loading (β) angles were observed in the layered Longmaxi shale. The normalized ATS for various orientation and loading angles achieved high values of 3.15 and 2.90, respectively, indicating that the influence of the orientation angle is slightly stronger than that of the loading angle. The Longmaxi shale exhibited a distinct tensile failure mode at α = 0° @ β = 0–15°, α = 0° @ β = 75–90°, and α = 90°, but a more complicated mixed mode of both tensile and shear failure was observed under other conditions. The contribution of shear failure increased significantly at 0° <α < 90° compared to α = 0°. The spacing of the bedding planes had a limited influence on the ATS and failure modes, but the bedding strength had a significant influence. There may be a linear relationship between bedding strength and the spatial distribution parameter of the critical plane approach criterion.
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