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The paper presents a geometric calibration method based on the sparse ground control points (GCPs), aiming to the linear push-broom optical satellite. This method can achieve the optimal estimate of internal and external parameters with two overlapped image pair along the charge-coupled device (CCD), and sparse GCPs in the image region, further get rid of the dependence on the expensive calibration site data. With the calibrated parameters, the line of sight (LOS) of all CCD detectors can be recovered. This paper firstly establishes the rigorous imaging model of linear push-broom optical satellite based on its imaging mechanism. And then the calibration model is constructed by improving the internal sensor model with a viewing-angle model after an analysis on systematic errors existing in the imaging model is performed. A step-wise solution is applied aiming to the optimal estimate of external and internal parameters. At last, we conduct a set of experiments on the ZY-3 NAD camera and verify the accuracy and effectiveness of the presented method by comparison.

Precious metal nanoclusters have unique electronic structure and fluorescent properties, and can be used as fluorescent probes in a wide range of applications such as biomarkers and ion detection. This paper reviews the preparation methods of thiol-protected silver clusters, including bottom-up and top-down methods, focusing on optimizing the reduction process of the reaction, selecting excellent thiol ligands, changing the pH values of the system, and strictly controlling. The research status of the preparation of thiol-protected silver clusters was introduced in terms of etching time and reaction temperature during the reaction, and ideas and suggestions for further research were provided. At the same time, based on the excellent fluorescence properties of thiol-protected silver clusters, the research progress in the detection of small molecules such as Cu2+, Hg2+, I- and cysteine was introduced. Finally, it was pointed out that the fluorescence quantum yield and safety of metal nanoclusters are improved, and the reaction mechanism of metal nanoclusters with heavy metal ions and biomacromolecules is studied in depth, and the synthesis methods of high purity and diversity alloy clusters or transition metal nanoclusters are explored. The preparation of fluorescent sensing materials for the realization of highly efficient thiol-protected silver clusters is a hot trend in future research.

The layered double hydroxides become research hot spot of oxygen evolution catalyzer for its easy preparation, feasible moderation of interlayer object,low cost and good stability but due to its low transmission speed of its electric charge,higher overpotential, so the modification is needed before mass application. The constructional character of the layered twinned material was firstly introduced, the catalytic mechanism of its oxygen evolution reaction was briefly described, then different kinds of optimization modification strategies to enhance its catalytic activity were introduced. The optimization modification strategies include:combination with conductive substrate, synthesis ultrathin nanometer plate, graphene compounding process, hybrid modification. The application of the stratified dihydride oxygen evolution catalyst in electrolysis of water to hydrogen and the advantages and disadvantages of different modification methods were put forward. The better-efficient oxygen evolution catalyst can be achieved through different kinds of modification. In the end, the difficulties in this kind of catalyzer were pointed out, including low recycle rate, catalyst stability, current density not meeting the requirements of industrialization and massive production.

Introduction: This study examines the interplay between online and offline social relationships by focusing on an understudied social group: older Chinese Internet users. Method: Thirty-three semi-structured open-ended interviews were conducted with members of a senior-oriented Chinese Internet community in 2004. Analysis: Interview data were recorded, transcribed, translated and coded following the principles of grounded theory. Results: Participants have been using the Internet to overcome geographical barriers and to integrate the virtual world into everyday life. Initial interactions in the online community promote the need for individuals to meet in the physical world with those who have similar interests and backgrounds. Interactions in the physical world in turn help weak tie relationships to develop into stronger ties. Conclusions: The online and offline worlds are mutually constructed and interacting through multiple communication channels is more likely to generate stronger relationships than interacting through a single channel.

Summary: In this paper, we study the task offloading optimization problem in satellite edge computing environments to reduce the whole communication latency and energy consumption so as to enhance the offloading success rate. A three‐tier machine learning framework consisting of collaborative edge devices, edge data centers, and cloud data centers has been proposed to ensure an efficient task execution. To accomplish this goal, we also propose a Q‐learning‐based reinforcement learning offloading strategy in which both the time‐sensitive constraints and data requirements of the computation‐intensive tasks are taken into account. It enables various types of tasks to select the most suitable satellite nodes for the computing deployment. Simulation results show that our algorithm outperforms other baseline algorithms in terms of latency, energy consumption, and successful execution efficiency. [ABSTRACT FROM AUTHOR]

The rapid development of medical imaging diagnostic technology makes high-definition CT image sequence(CIS)s more and more important for clinical diagnosis as well as medical research. Given a retrieval CIS, it can effectively assist physicians' diagnosis to retrieve similar CISs from the large-scale CIS database. The state-of-the-art content-based medical image similarity retrieval often adopts single CI as a retrieval one rather than CIS, and the retrieval accuracy is usually not satisfactory. To address this issue, we take lung CIS as an example and propose a progressive Content-based Similarity Retrieval method for the lung CISs (CSRS) based on a Weakly Supervised Learning & Evaluation Network(WSLEN) model. Three enabling techniques (i.e., the WSLEN model, KCI-based similarity measure of CISs, and the distance-based indexing scheme) are proposed to facilitate the CSRS processing of the large lung CISs. Extensive experiments show that the WSLEN-based CSRS method is superior to the two competitors such as the CNNSH [2] and the DSH [12] in terms of the retrieval accuracy; and the DIndex-support CSRS method is superior to that of the sequential scan by a large margin according to the retrieval efficiency. [ABSTRACT FROM AUTHOR]

In this paper, a composite pressure-sensitive mechanism combining diaphragm bending and volume compression was developed for resonant pressure microsensors to achieve high-pressure measurements with excellent accuracy. The composite mechanism was explained, and the sensor structure was designed based on theoretical analysis and finite element simulation. An all-silicon resonant high-pressure microsensor with multiple miniaturized cavities and dual resonators was developed, where dual resonators positioned in two resonant cavities with suitably different widths are used to perform opposite characteristics in pressure and the same characteristics at different temperatures, which can improve pressure sensitivities and realize temperature self-compensation by differential frequency output. The microsensor was fabricated by microfabrication, and the experimental results showed that the sensor had an accuracy of ±0.015% full scale (FS) in a pressure range of 0.1~100 MPa and a temperature range of −10~50 °C. The pressure sensitivity of the differential frequency was 261.10 Hz/MPa (~2523 ppm/MPa) at a temperature of 20 °C, and the temperature sensitivities of the dual resonators were −1.54 Hz/°C (~−14.5 ppm/°C) and −1.57 Hz/°C (~−15.6 ppm/°C) at a pressure of 2 MPa. The differential output had an outstanding stability within ±0.02 Hz under constant temperature and pressure. Thus, this research provides a convenient solution for high-pressure measurements because of its advantages, namely, large range, excellent accuracy and stability. [ABSTRACT FROM AUTHOR]

To ameliorate the thermal performance of micro combustor and expand its potential applications, a combustor with partially Pt-loaded porous media is constructed. Experiments of H 2 /CH 4 blending combustion in the combustors with different materials for catalyst Pt supported porous media are carried out, and effects of flow rate and fuels blended ratio and porous media setting are also involved. The results show that the nickel-based porous media for supported catalyst Pt achieves stable flame and efficient thermal performance. The homogeneous reactions are inhibited by the global catalytic combustion in the porous media, which reduces the flame temperature in the combustion chamber. The partially inserted catalytic porous media can balance the inhibition of heterogeneous reactions on homogeneous reactions, altering the anchoring of flame and promoting heat-recirculation in the combustion chamber to enhance the combustion stability of H 2 /CH 4 /Air. A sub-high temperature region is formed in the combustor downstream, which boosts the radiation performance of the combustor. The #CPC combustor achieves the maximum radiation power and efficiency of 63.7 W and 56.7 %, which represents a 10.3 % increase in radiation efficiency compared to non-catalytic combustion. • A combustor with partially Pt-loaded porous media is proposed for H 2 /CH 4 fueled combustion. • Effects of Pt supported with varied porous materials on the combustion are obtained. • The partially inserted catalytic porous media contributes to flame stability and energy conversion. • Radiation efficiency can be 10.3 % improved for the burner with partially Pt-loaded porous media. [ABSTRACT FROM AUTHOR]

Aims: There has been a lack of research examining the relationship between red cell distribution width (RDW) and the prognosis of cardiac arrest (CA) patients. The prognostic value of the changes in RDW during intensive care unit (ICU) hospitalization for CA patients has not been investigated. This study aims to investigate the correlation between RDW measures at ICU admission and RDW changes during ICU hospitalization and the prognosis of CA patients and then develop a nomogram that predicts the risk of mortality of these patients. Methods and results: A retrospective cohort study is used to collect clinical characteristics of CA patients (>18 years) that are on their first admission to ICU with RDW data measured from the Medical Information Mart for Intensive Care IV Version 2.0 database. Patients are randomly divided into a development cohort (75%) and a validation cohort (25%). The primary outcome is 30 and 360 day all‐cause mortality. ΔRDW is defined as the RDW on ICU discharge minus RDW on ICU admission. A multivariate Cox regression model is applied to test whether the RDW represents an independent risk factor that affects the all‐cause mortality of these patients. Meanwhile, the dose–response relationship between the RDW and the mortality is described by restricted cubic spine (RCS). A prediction model is constructed using a nomogram, which is then assessed using receiver operating characteristic curves, calibration curves, and decision curve analysis (DCA). A total of 1278 adult CA patients are included in this study. We found that non‐survivors have a higher level of RDW and ΔRDW compared with survivors, and the mortality rate is higher in the high RDW group than in the normal RDW group. The Kaplan–Meier survival curve indicates that patients in the normal RDW group had a higher cumulative survival rate at 30 and 360 days than those in the high RDW group (log‐rank test, χ2 = 36.710, χ2 = 54.960, both P values <0.05). The multivariate Cox regression analysis shows that elevated RDW at ICU admission (>15.50%) is an independent predictor of 30 [hazard ratio = 1.451, 95% confidence interval (CI) = 1.181–1.782, P < 0.001] and 360 day (hazard ratio = 1.393, 95% CI = 1.160–1.671, P < 0.001) all‐cause mortality among CA patients, and an increase in RDW during ICU hospitalization (ΔRDW ≥ 0.4%) can serve as an independent predictor of mortality among these patients. A non‐linear relationship between the RDW measured at ICU admission and the increased risk of mortality rate of these patients is shown by the RCS. This study established and validated a nomogram based on six variables, anion gap, first‐day Sequential Organ Failure Assessment score, cerebrovascular disease, malignant tumour, norepinephrine use, and RDW, to predict mortality risk in CA patients. The consistency indices of 30 and 360 day mortality of CA patients in the validation cohort are 0.721 and 0.725, respectively. The nomogram proved to be well calibrated in the validation cohort. DCA curves indicated that the nomogram provided a higher net benefit over a wide, reasonable range of threshold probabilities for predicting mortality in CA patients and could be adapted for clinical decision‐making. Conclusions: Elevated RDW levels on ICU admission and rising RDW during ICU hospitalization are powerful predictors of all‐cause mortality for CA patients at 30 and 360 days, and they can be used as potential clinical biomarkers to predict the bad prognosis of these patients. The newly developed nomogram, which includes RDW, demonstrates high efficacy in predicting the mortality of CA patients. [ABSTRACT FROM AUTHOR]

We aim to share our experience of the removal of cranio-orbital lesions (COLs) and propose a novel classification to guide the tailored approach selection. We retrospectively reviewed 45 consecutive patients with COLs who underwent surgery performed by the same neurosurgeon between November 2010 and November 2022. The surgical approach was selected according to the anatomical region classification of the COLs. For lesions limited to space A (lateral superior orbital fissure, SOF), the pterion or extended pterion approach (PA or EPA) was used. For lesions limited to space B (extraconal compartment medial SOF, and cavernous sinus CS) and C (intraconal compartment, medial SOF, and CS), the pretemporal transcavernous approach (PTCA) was used. For lesions limited to space D (intraconal compartment and optic canals), the subfrontal approach (SA) was used. For lesions extending into the infratemporal fossa (ITF), the cranio-orbito-zygomatic approach (COZA) was used. For lesions involving pterygopalatine fossa (PPF), the endoscopic transnasal approach (ETNA) was used. We analyzed the clinical manifestations, imaging data, surgical approaches, surgical outcomes, neurological outcomes, and follow-up data. Gross total resection was performed in 35 patients (35/45, 77.8%). SA, PA, EPA, PTCA, COZA, and ETNA were performed in 9, 9, 10, 10, 6, and 1 case(s), respectively. Progression of the residual tumor was observed in 6 cases (1 adenoid cystic carcinoma and 5 meningiomas). Surgical approach selection plays a vital role in patient prognosis. This novel classification based on the involvement of anatomic space could help surgeons select an appropriate approach to remove the COLs. [ABSTRACT FROM AUTHOR]

Background: In many areas of China, over 30% of tuberculosis cases occur among the elderly. We aimed to investigate the spatial distribution and environmental factors that predicted the occurence of tuberculosis in this group. Methods: Data were collected on notified pulmonary tuberculosis (PTB) cases aged ≥ 65 years in Zhejiang Province from 2010 to 2021. We performed spatial autocorrelation and spatial-temporal scan statistics to determine the clusters of epidemics. Spatial Durbin Model (SDM) analysis was used to identify significant environmental factors and their spatial spillover effects. Results: 77,405 cases of PTB among the elderly were notified, showing a decreasing trend in the notification rate. Spatial-temporal analysis showed clustering of epidemics in the western area of Zhejiang Province. The results of the SDM indicated that a one-unit increase in PM2.5 led to a 0.396% increase in the local notification rate. The annual mean temperature and precipitation had direct effects and spatial spillover effects on the rate, while complexity of the shape of the greenspace (SHAPE_AM) and SO2 had negative spatial spillover effects. Conclusion: Targeted interventions among the elderly in Western Zhejiang may be more efficient than broad, province-wide interventions. Low annual mean temperature and high annual mean precipitation in local and neighboring areas tend to have higher PTB onset among the elderly. [ABSTRACT FROM AUTHOR]

Tread wear rates of the right and left wheels of a wheelset are not the same because of the complexity of the track condition, which causes the wheel diameter difference (WDD). The WDD can influence vehicle dynamic performances and shorten the service life of the wheelset. To diagnose and recognize the condition of the WDD in time, a data-driven method based on multi-sensor information fusion is proposed. Different statistical features are extracted from the time and frequency domains of the axle-box acceleration signals. The features can be fused by integrating stacked autoencoder and multiple kernel learning. The comparative experimental analysis shows that compared with other commonly used intelligent methods, the proposed method can achieve higher diagnostic accuracy and give better performance with small training sample sizes. The statistical features sensitive to the WDD are also analyzed for industrial application. [ABSTRACT FROM AUTHOR]

In recent years, the COVID-19 pandemic and other global crises have significantly affected the lives of older adults, impacting their healthcare, social connections, and daily routines. While the increasing digitization and automation of services offer benefits such as remote healthcare access and reduced isolation, these technologies also pose challenges in terms of unfamiliarity, learning curves, and privacy and security concerns. Addressing these issues requires a collaborative approach across various fields, including health informatics, gerontology, social psychology, human–computer interaction, and cybersecurity and privacy. Understanding the cognitive, emotional, and sociocultural factors influencing older adults' use of technologies is crucial for creating inclusive and accessible digital tools. This multidisciplinary effort, as highlighted in the special issue of Work, Aging and Retirement, aims to enhance our understanding of aging and technology in today's world, empowering older adults to remain connected and maintain their well-being. [ABSTRACT FROM AUTHOR]