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Online mutual aid (MA) is a novel form of ex‐post risk sharing empowered by InsurTech to provide critical illness coverage without involving an insurer. In this paper, we first provide a rigorous examination of the underpinning theory and analyze MA model's cost‐effectiveness. In addition, we theoretically investigate the condition for MA's actuarial fairness among all participants. Our numerical illustration also shows that current MA plans lack the consideration of actuarial fairness as they differentiate members only by gender and age group of large bandwidths. Last, our empirical analysis confirms the existence of adverse selection due to the lack of actuarial fairness. [ABSTRACT FROM AUTHOR]

Background: Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is a standardized semi‐quantitative method for early ischemic changes in acute ischemic stroke. Purpose: However, ASPECTS is still affected by expert experience and inconsistent results between readers in clinical. This study aims to propose an automatic ASPECTS scoring model based on diffusion‐weighted imaging (DWI) mode to help clinicians make accurate treatment plans. Methods: Eighty‐two patients with stroke were included in the study. First, we designed a new deep learning network for segmenting ASPECTS scoring brain regions. The network is improved based on U‐net, which integrates multiple modules. Second, we proposed using hybrid classifiers to classify brain regions. For brain regions with larger areas, we used brain grayscale comparison algorithm to train machine learning classifiers, while using hybrid feature training for brain regions with smaller areas. Results: The average DICE coefficient of the segmented hindbrain area can reach 0.864. With the proposed hybrid classifier, our method performs significantly on both region‐level ASPECTS and dichotomous ASPECTS. The sensitivity and accuracy on the test set are 95.51% and 93.43%, respectively. For dichotomous ASPECTS, the intraclass correlation coefficient (ICC) between our automated ASPECTS score and the expert reading was 0.87. Conclusions: This study proposed an automated model for ASPECTS scoring of patients with acute ischemic stroke based on DWI images. Experimental results show that the method of segmentation first and then classification is feasible. Our method has the potential to assist physicians in the Alberta Stroke Program with early CT scoring and clinical stroke diagnosis. [ABSTRACT FROM AUTHOR]

In this study, we report the modulation of the emission color and optical temperature‐sensing properties of Er3+ in Ba5Zn4Y8O21 crystals. Er3+ single‐doped Ba5Zn4Y8O21 phosphors showed green emission under 980 nm excitation. When codoping with Yb3+ ions, the red emission component from the Er3+ ions increased significantly, and the sample emission turned orange. Yb3+–Er3+ codoped Ba5Zn4Y8O21 samples exhibited bright red emission with a maximum IR/IG value of 89.30 when excited with a longer wavelength, 1550 nm. A broad range of emission colors could be modulated by adjusting the dopant concentration. The possible modulation mechanisms and upconversion processes were analyzed based on the luminescence decay curves and power‐dependent emission intensities. Furthermore, the optical temperature‐sensing properties of Ba5Zn4Y8O21:Er3+ and Ba5Zn4Y8O21:Er3+, Yb3+ phosphors with thermal coupled energy levels (TCELs) and nonthermal coupled energy levels (N‐TCELs) of Er3+ ions were investigated using fluorescence intensity ratio technique. Based on the TCELs (2H11/2/4S3/2), the Er3+ single‐doped and Yb3+–Er3+ codoped Ba5Zn4Y8O21 phosphors present the similar optical thermometry behaviors under 980 and 1550 nm excitation. The highest absolute (Sa) and relative sensitivity (Sr) are 3.95 × 10−3 K−1 at 573 K and 1.31% K−1 at 303 K, respectively. Based on N‐TCELs (4F9/2/2H11/2), the temperature‐sensing performance depends on the Yb3+ dopant and excitation wavelength. The highest values for Sa and Sr reached 5.46 K−1 at 303 K and 1.38% K−1 at 573 K for the Ba5Zn4Y8O21:Er3+, Yb3+ phosphor under 1550 nm excitation, respectively. In addition, the present phosphor exhibited high stability and repeatability over a wide temperature range. These results indicate that the multicolor modulation upconversion Ba5Zn4Y8O21‐based phosphor can be considered a potential reusable optical thermometer for noncontact temperature detection. [ABSTRACT FROM AUTHOR]

Background: Breast MRI has been recommended as supplemental screening tool to mammography and breast ultrasound of breast cancer by international guidelines, but its long examination time and use of contrast material remains concerning. Purpose: To develop an unenhanced radiomics model with using non‐gadolinium based sequences for detecting breast cancer based on T2‐weighted (T2W) and diffusion‐weighted (DW) MRI. Study Type: Retrospective analysis followed by retrospective and prospective cohorts study. Population: 1760 patients: Of these, 1293 for model construction (n = 775 for training and 518 for validation). The remaining patients for model testing in internal retrospective (n = 167), internal prospective (n = 188), and external retrospective (n = 112) cohorts. Field Strength/Sequence: 3.0T MR scanners from two institution. T2WI, DWI, and first contrast‐enhanced T1‐weighted sequence. Assessment: AUCs in distinguishing breast cancer were compared between combined model with gadolinium agent sequence and unenhanced model. Subsequently, the AUCs in testing cohorts of unenhanced model was compared with two radiologists' diagnosis for this research. Finally, patient subgroup analysis in testing cohorts was performed based on clinical subgroups and different types of malignancies. Statistical Tests: Mann–Whitney U test, Kruskal‐Wallis H test, chi‐square test, weighted kappa test, and DeLong's test. Results: The unenhanced radiomics model performed best under Gaussian process (GP) classifiers (AUC: training, 0.893; validation, 0.848) compared to support vector machine (SVM) and logistic, showing favorable prediction in testing cohorts (AUCs, 0.818–0.840). The AUCs for the unenhanced radiomics model were not statistically different in five cohorts from those of the combined radiomics model (P, 0.317–0.816), as well as the two radiologists (P, 0.181–0.918). The unenhanced radiomics model was least successful in identifying ductal carcinoma in situ, whereas did not show statistical significance in other subgroups. Data Conclusion: An unenhanced radiomics model based on T2WI and DWI has comparable diagnostic accuracy to the combined model using the gadolinium agent. Level of Evidence: 4 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Methane as the main component in natural gas is a promising chemical raw material for synthesizing value‐added chemicals, but its harsh chemical conversion process often causes severe energy and environment concerns. Photocatalysis provides an attractive path to active and convert methane into various products under mild conditions with clean and sustainable solar energy, although many challenges remain at present. In this review, recent advances in photocatalytic methane conversion are systematically summarized. As the basis of methane conversion, the activation of methane is first elucidated from the structural basis and activation path of methane molecules. The study is committed to categorizing and elucidating the research progress and the laws of the intricate methane conversion reactions according to the target products, including photocatalytic methane partial oxidation, reforming, coupling, combustion, and functionalization. Advanced photocatalytic reactor designs are also designed to enrich the options and reliability of photocatalytic methane conversion performance evaluation. The challenges and prospects of photocatalytic methane conversion are also discussed, which in turn offers guidelines for methane‐conversion‐related photocatalyst exploration, reaction mechanism investigation, and advanced photoreactor design. [ABSTRACT FROM AUTHOR]

This study investigates the deformation characteristics of SiO2–MnO–(CaO–Al2O3)‐type inclusions in silicon manganese deoxidized steel from continuous casting to rolling. The results reveal that the inclusions contain 60–80% SiO2, 10–35% MnO, and a combined CaO and Al2O3 content of <20%. SiO2 precipitates inside the inclusions during the continuous casting and rolling processes, which results in the formation of pure SiO2/SiO2–MnO–(CaO–Al2O3) dual‐phase inclusions in the remaining components owing to the increase in the MnO content to 15–40%. According to the experimental results of melting rate measurement and thermodynamic calculation using FactSage8.1, the SiO2–MnO–(CaO–Al2O3) phase has a high proportion of liquid components at 1100–1360 °C and exhibits good deformation properties during the breaking down and rolling processes. When the total content of CaO, Al2O3, and MgO in the SiO2–CaO–Al2O3–MgO–MnO inclusions reaches 30–50%, SiO2 precipitation is inhibited during the continuous casting to rolling process. Through the addition of metal manganese and carbon powder during the pre‐deoxidation process, followed by alloying with ferrosilicon and metal manganese, and then the addition of acidic synthetic slag for slag formation, the proportion of SiO2/SiO2–MnO–(CaO–Al2O3) dual‐phase inclusions in the casting billet is increased from 12% to >60%. [ABSTRACT FROM AUTHOR]

A novel compact microstrip second‐order lossy bandpass filter (BPF) based on an improved simplified composite right‐/left‐handed zeroth‐order resonator (ISZOR) is presented in this paper. The microstrip ISZOR (MISZOR) features miniature topology and ample adjustable physical parameters accompanied by its easily controllable zeroth‐order base mode and first harmonic. Its layout can be quickly generated by applying the implicit space mapping technique. By virtue of the lossy coupling matrix synthesis method, the finite unloaded quality factor of the MISZOR can be taken into account in advance to foretell the insertion loss level. A new definition of the external quality factor as well as its full‐wave extraction method is introduced, enabling the targetted second‐order lossy BPF to be directly implemented as in the classical lossless design, despite the existence of the parallel resistor loaded nonresonant node at each terminal. A succinct inductive coupled microstrip corner is conceived to achieve the relatively strong terminal coupling strength. The exemplified lossy BPF centers at 3.1 GHz with a fractional bandwidth of 5%, which is automatically optimized with the Nelder–Mead simplex algorithm. A prototype measurement is carried out, and good agreement is achieved with simulation, testifying the proposed design concept. [ABSTRACT FROM AUTHOR]

Previous studies have mainly focused on examining families' struggles during the adaptive process of adversity, while the strength of family and how it arises were neglected. This study aims to explore the relationships between individual and family resilience among parents and children in families during COVID‐19. Guided by the longitudinal actor–partner interdependence model, one parent and a child in 136 Chinese families completed assessments of pandemic media exposure and individual resilience in mid‐February 2020 and family resilience in early March. Results showed that the child's individual resilience was positively associated with their own and their parents' family resilience, while parents' resilience was only positively associated with their own. The evidence indicated that a child's individual resilience was critical for all core family members' perceived family resilience and provided implications for family intervention programs. [ABSTRACT FROM AUTHOR]

Polyamines are small aliphatic polycations present in all living organisms. In plants, the most abundant polyamines are putrescine (Put), spermidine (Spd) and spermine (Spm). Polyamine levels change in response to different pathogens, including Pseudomonas syringae pv. tomato DC3000 (Pst DC3000). However, the regulation of polyamine metabolism and their specific contributions to defence are not fully understood. Here we report that stimulation of Put biosynthesis by Pst DC3000 is dependent on coronatine (COR) perception and jasmonic acid (JA) signalling, independently of salicylic acid (SA). Conversely, lack of Spm in spermine synthase (spms) mutant stimulated galactolipids and JA biosynthesis, and JA signalling under basal conditions and during Pst DC3000 infection, whereas compromised SA‐pathway activation and defence outputs through SA–JA antagonism. The dampening of SA responses correlated with COR and Pst DC3000‐inducible deregulation of ANAC019 expression and its key SA‐metabolism gene targets. Spm deficiency also led to enhanced disease resistance to the necrotrophic fungal pathogen Botrytis cinerea and stimulated endoplasmic reticulum (ER) stress signalling in response to Pst DC3000. Overall, our findings provide evidence for the integration of polyamine metabolism in JA‐ and SA‐mediated defence responses, as well as the participation of Spm in buffering ER stress during defence. Summary statement: Spermine deficiency stimulates the biosynthesis of galactolipids and jasmonic acid, while it dampens the biosynthesis of salicylic acid, thereby conditioning defence outputs. [ABSTRACT FROM AUTHOR]

This paper combines new palaeomagnetic studies, palaeontological dating, and sedimentary analyses to propose a modified stratigraphic classification scheme in the northwestern Songliao Basin, which is of great significance for stratigraphic correlation, sedimentation analysis, basinal subsidence, and oil and gas exploration. New palaeontological and palaeomagnetic evidence redefined a group of semi‐consolidated lacustrine strata, buried beneath the Quaternary Yaluhe Formation on the Western Slope of the Songliao Basin, as Late Cretaceous, not the Middle Pleistocene. The chronostratigraphic framework re‐evaluates its stratigraphic age as late Coniacian to early Campanian (Late Cretaceous), between 83 and 85 Ma. Sedimentation research from 17 boreholes on the Western Slope of the Songliao Basin displays that the semi‐consolidated strata successively experienced lacustrine and delta facies deposits. Comparison of this new stratigraphy with the Late Cretaceous sequences on the adjacent Central Depression of the Songliao Basin reveals significant variations in lithology and palynological assemblages. Three new palynological assemblages are also reported from the Late Cretaceous sequences of the Songliao Basin. [ABSTRACT FROM AUTHOR]

Aqueous Mg ion batteries (AMIBs) show great potential in energy storage for their advantages of high capacity, abundant resource, and environmental friendliness. However, the development of AMIBs is limited due to the scarcity of suitable anode materials. In this study, a new polymer anode material (PNTAQ) with flower‐like nanosheet structure is synthesized for aqueous Mg‐Na hybrid‐ion battery (AMNHIB). PNTAQ possess carbonyl functional groups which can be oxidized and reduced reversibly in aqueous solution containing alkaline metal ions. PNTAQ displays a discharge specific capacity of 245 mAh g−1 at 50 mA g−1 in 1 M MgCl2 + 0.5 M NaCl electrolyte, which is much higher than that in single 1 M MgCl2 or 0.5 M NaCl electrolyte. Even cycling at 1000 mA g−1 for 1000 times, the capacity retention can still maintain at 87.2%. A full Mg‐Na hybrid‐ion cell is assembled by employing β‐MnO2 as cathode and PNTAQ as anode material, it exhibits a specific capacity of 91.6 mAh g−1 at 100 mA g−1. The polymer electrode material well maintains its framework structure during the discharge/charge cycling process of the hybrid‐ion battery. [ABSTRACT FROM AUTHOR]

Methane conversion to higher hydrocarbons requires harsh reaction conditions due to high energy barriers associated with C−H bond activation. Herein, we report a systematic investigation of photocatalytic oxidative coupling of methane (OCM) over transition‐metal‐loaded ZnO photocatalysts. A 1 wt % Au/ZnO delivered a remarkable C2‐C4 hydrocarbon production rate of 683 μmol g−1 h−1 (83 % C2‐C4 selectivity) under light irradiation with excellent photostability over two days. The metal type and its interaction with ZnO strongly influence the selectivity toward C−C coupling products. Photogenerated Zn+‐O− sites enable CH4 activation to methyl intermediates (*CH3) migrating onto adjacent metal nanoparticles. The nature of the *CH3‐metal interaction controls the OCM products. In the case of Au, strong d‐σ orbital hybridization reduces metal‐C−H bond angles and steric hindrance, thereby enabling efficient methyl coupling. Findings indicate the d‐σ center may be a suitable descriptor for predicting product selectivity during OCM over metal/ZnO photocatalysts. [ABSTRACT FROM AUTHOR]

In this paper, the Earth's sporadic‐E (Es) layer vertical motion is investigated by using an image processing technique for automatic scaling ionograms from Mohe (122.37°E, 53.50°N, dip angle 71°), Beijing (116.25°E, 40.25°N, dip angle 59°), Wuhan (114.61°E, 30.53°N, dip angle 46°) and Fuke (109.13°E, 19.52°N, dip angle 27°). Es traces descend with different periodicities, indicating tidal modulation to Es layers. Comparing winds from a combination of the Ionospheric Connection Explorer/Michelson Interferometer for Global High‐Resolution Thermospheric Imaging and meteor radar measurements with Es layers, we find that Es traces at high altitudes (above 110 km) rapidly move down in accordance with the descent of the wind shear nulls, which indicates the important role of the tides in the formation and descent of the Es layer at high altitude. The lower‐lying Es layers, however, do not descend with the wind shear null, but stay at the bottom of the E region (∼100 km) for a long time, which cannot be explained by tidal wind shear theory. In addition, the time duration of the Es layers staying at low latitudes increases with the decreasing latitude. Simulation results demonstrate that the low altitude tailing Es layer is dominated by the dramatically enhanced collision frequency at the lower height of the mesosphere and the lower thermosphere region. Plain Language Summary: Sporadic‐E (Es) layers are stochastic ionospheric plasma irregularities at ionospheric E region, which can significantly affect the propagation of radio waves in the ionosphere, hence are of particular interest for modern electronic systems such as HF/VHF communication systems, skywave over‐the‐horizon radars, and shortwave electronic reconnaissance/localization systems. The intensity and occurrence of Es layers exhibits complex variations in space and time, depending on the nature of atmospheric, solar and geomagnetic activities. Because of the highly complex behavior of the Es layer, the prediction of its occurrence has been one of the most difficult issues in space weather forecast. In this study, the image processing technique is used to investigate the vertical motion of the Es layer at different latitudes. Observational results demonstrate that the Es formation and movement at high altitudes are controlled by tides with different periods. However, at low altitudes, Es layers descend at a slow speed and stay at low altitudes for a long time. Observation and simulation results show that the formation of Es layers at higher altitude (above 110 km) is ascribed to the traditional wind shear theory, while the lower‐lying Es traces lasting for a long time is controlled by the dramatically enhanced collision frequency. Key Points: Michelson Interferometer for Global High‐Resolution Thermospheric Imaging/Ionospheric Connection Explorer and meteor radar measurements are combined to study the relationship between sporadic‐E (Es) layer and wind shearThe time duration of the Es layer staying at lower altitudes increases with decreasing latitudeSimulation driven by winds from the Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension model reproduces the tailing Es layer at the bottom of the E region [ABSTRACT FROM AUTHOR]

The activation of water molecules in thermal catalysis typically requires high temperatures, representing an obstacle to catalyst development for the low‐temperature water‐gas shift reaction (WGSR). Plasmonic photocatalysis allows activation of water at low temperatures through the generation of light‐induced hot electrons. Herein, we report a layered double hydroxide‐derived copper catalyst (LD‐Cu) with outstanding performance for the low‐temperature photo‐driven WGSR. LD‐Cu offered a lower activation energy for WGSR to H2 under UV/Vis irradiation (1.4 W cm−2) compared to under dark conditions. Detailed experimental studies revealed that highly dispersed Cu nanoparticles created an abundance of hot electrons during light absorption, which promoted *H2O dissociation and *H combination via a carboxyl pathway, leading to the efficient production of H2. Results demonstrate the benefits of exploiting plasmonic phenomena in the development of photo‐driven low‐temperature WGSR catalysts. [ABSTRACT FROM AUTHOR]

Methanol steam reforming (MSR) is viewed as an important technology in the growth of a future hydrogen economy, with methanol serving as an easily transportable and storable liquid hydrogen carrier. However, the thermocatalytic MSR reaction is energy intensive as it requires high temperatures. Herein, a novel L‐Cu catalyst is successfully fabricated for photo‐driven MSR through reduction of CuAl layered double hydroxide (CuAl‐LDH) nanosheets. L‐Cu offers outstanding activity for the photothermal conversion of methanol and water to hydrogen (160.5 µmol gcat−1 s−1) under ultraviolet‐visible irradiation, with this rate being much higher than that achieved for L‐Cu at the same temperature in the dark. Characterization studies using X‐ray diffraction, X‐ray photoelectron spectroscopy, X‐ray absorption spectroscopy, and high‐resolution transmission electron microscopy determine that L‐Cu catalyst comprise Cu nanoparticles on an amorphous alumina support. Computational calculations reveale that Cu localized surface plasmon resonance effects promote the activation of H2O, thereby underpinning the remarkable hydrogen production rates achieved during photo‐driven MSR. This study introduces a novel photothermal strategy for hydrogen generation from methanol, demonstrating the enormous potential of photothermal catalysis in the chemical and energy sectors. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the potential application of computer‐aided analysis in the quantitative assessment of changes in skeletal muscle injury in the rabbit contusion model. Forty healthy rabbits were randomly divided into control (n = 5) and contusion (n = 35) groups. Rabbits in the contusion group were used to construct a muscle contusion model induced by a hammer hitting the right gastrocnemius, while the muscles of rabbits in the control group were non‐injured. Two‐dimensional ultrasound (2D US) and contrast‐enhanced ultrasonography (CEUS) were performed on the rabbits that had received skeletal muscle contusion injury at 1 h, and 1, 3, 7, 14, 21 and 28 days after injury. Afterwards, a multiscale blob feature (MBF) method was used to extract the textural features from the 2D US, and the muscle injuries were quantitatively evaluated. The eight textural parameters of skeletal muscle analysed by MBF at 1 h, and 1, 3 and 7 days post‐injury were found to be significantly higher in the contusion group than in the control group (p <.05). On Day 14, the textural parameters (e.g., greyscale mean [Mean], greyscale standard deviation [SDev], number of blobs, average size of blobs, homogeneity of distribution, periodicity of distribution [POD] and irregularity) were also evidently higher in the contusion group than in the control group (p <.05). On Day 28, Mean, SDev and POD in the contusion group were markedly higher (p <.05). After that, the microcirculation in the injured areas increased from Day 7 to Day 21 after injury, but decreased on Day 28 after injury. Thus the quantitative assessment of changes in skeletal muscle injury (SMI) using computer‐aided analysis allowed us to describe the geometric features of injured muscle fibres and the microperfusion changes estimated by the modified semi‐quantitative scoring system. This provides a scientific basis for the development of a novel approach for the evaluation of SMI and rehabilitation process. [ABSTRACT FROM AUTHOR]

Background: Endometrial carcinoma (EC) is one of the most common gynecological malignancies with an increasing incidence, and an accurate preoperative diagnosis of deep myometrial invasion (DMI) is crucial for personalized treatment. Objective: To determine the predictive value of a magnetic resonance imaging (MRI)‐based radiomics nomogram for the presence of DMI in the International Federation of Gynecology and Obstetrics (FIGO) stage I EC. Methods: We retrospectively collected 163 patients with pathologically confirmed stage I EC from two centers and divided all samples into a training group (Center 1) and a validation group (Center 2). Clinical and routine imaging indicators were analyzed by logistical regression to construct a conventional diagnostic model (M1). Radiomics features extracted from the axial T2‐weighted and axial contrast‐enhanced T1‐weighted (CE‐T1W) images were treated with the intraclass correlation coefficient, Mann–Whitney U test, least absolute shrinkage and selection operator, and logistic regression analysis with Akaike information criterion to build a combined radiomics signature (M2). A nomogram (M3) was constructed by M1 and M2. Calibration and decision curves were drawn to evaluate the nomogram in the training and validation cohorts. The diagnostic performance of each indicator and model was evaluated by the area under the receiver operating characteristic curve (AUC). Result: The four most significant radiomics features were finally selected from the CE‐T1W MRI. For the diagnosis of DMI, the AUCT/AUCV of M1 was 0.798/0.738, the AUCT/AUCV of M2 was 0.880/0.852, and the AUCT/AUCV of M3 was 0.936/0.871 in the training and validation groups, respectively. The calibration curves showed that M3 was in good agreement with the ideal values. The decision curve analysis suggested potential clinical application values of the nomogram. Conclusion: A nomogram based on MRI radiomics and clinical imaging indicators can improve the diagnosis of DMI in patients with FIGO stage I EC. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction reaction (CO2RR) is an attractive process to convert CO2 into valuable chemicals. But this reaction is often restricted by the poor mass transfer of CO2 in the liquid phase. Here, we have developed a triphase photocatalytic CO2RR system by supporting Ag‐decorated TiO2 nanoparticles at a gas–water boundary with hydrophobic–hydrophilic abrupt interfacial wettability. Such a triphase system allows the rapid delivery of gas‐phase CO2 to the surface of photocatalysts while maintaining an efficient water supply and uncovered active sites. Ag‐TiO2 supported at the gas–water boundary showed a CO2 reduction rate of 305.7 μmol g−1 h−1, without hole scavengers, approximately 8 times higher than the nanoparticles dispersed in the liquid phase. Even using diluted CO2 (10 %) as the reactant, the CO2RR activity was superior to most reported Ag‐TiO2 based photocatalysts using pure CO2. The findings provide a general strategy to promote the interfacial CO2 mass transfer to improve photoactivity and selectivity. [ABSTRACT FROM AUTHOR]

A longitudinal chain and a latitudinal chain of ionosondes, located at Yakutsk (129.60°E, 62.00°N), Mohe (122.37°E, 53.50°N), Beijing (116.25°E, 40.25°N), Wuhan (114.61°E, 30.53°N), Sanya (109.42°E, 18.34°N), I‐Cheon (127.54°E, 37.14°N), San Vito (17.80°E, 40.60°N), Roquest (0.50°E, 40.80°N), Millstone Hill (71.50°W, 42.60°N), and Alpena (83.56°W, 45.07°N) ionosondes, are utilized to statistically investigate the sporadic E layer (Es) occurrence rate and variation. The Es occurrence rates at all stations show a similar dependence on local time and season. However, the seasonal dependence of Es occurrence is more distinct at middle latitudes than that at low latitudes along the 120°E longitude. Results at different stations along ∼40°N latitude show much lower Es occurrence at the American sector than that at European and East Asian sectors, which is most likely because the horizontal geomagnetic field in north America is smaller than in other regions. The statistical results demonstrate that the seasonal variations of Es occurrence and strength are related to the annual variation of meteor counts. Simulation results show that the summer maximum of the ion vertical drift velocity driven by the variations of neutral densities and winds could also contribute to the seasonal variations of Es occurrence and intensity. The seasonal variations of the quasi‐6‐day and quasi‐16‐day oscillations in Es are also investigated. The seasonal variations of periodic disturbances of the Es differ between each station. Planetary waves in the MLT region cannot fully explain the seasonal variations of the periodic disturbance of Es. Solar and geomagnetic activities can also result in periodic variations of the Es. Plain Language Summary: Sporadic E layer is an ionized cloud composed of metallic ions. Meteor flux and atmospheric waves, such as planetary waves and tides, play an important role in the formation of Es. In this work, we investigate the latitudinal and longitudinal distribution of Es occurrence and variations based on ionosonde data of 10 stations around the world. The Es occurrence rates at all stations show a similar dependence on season, which are mostly related to the variation of meteor input. In addition, simulation results show that the summer maximum of the ion vertical drift velocity driven by the variations of neutral densities and winds could also contribute to the seasonal variation of Es occurrence and intensity. The seasonal variations of quasi‐6‐day and quasi‐16‐day oscillation in sporadic E layer are also studied. The results demonstrate that the seasonal variations of periodic disturbances in Es differ between each station and enhanced quasi periodic oscillation can be observed in all seasons. Besides, in addition to the PWs in the MLT region, geomagnetic and solar activities can also lead to the periodic disturbance in Es layers. Key Points: The occurrence rate of Es in north America is lower than that at 120{degree sign}E sector due to horizontal geomagnetic field differenceEffects of meteor counts, neutral density, and winds contribute to the seasonal dependence of Es layer occurrenceSolar and geomagnetic activities can also contribute to the periodic oscillations in the Es layer variations [ABSTRACT FROM AUTHOR]

In this paper, we examine the mechanism of middle‐ and low‐latitude sporadic‐E (Es) layer formation. Observations of ionosondes and meteor radars at stations of different latitudes show that Es layer also formed at low‐altitude nonwindshear points, which is distinct from prototypical windshear theory. The theoretical modeling results show that metallic ions can effectively accumulate by the combined effect of the zonal and meridional winds in the mesosphere and the lower thermosphere region. Numerical simulation results also demonstrate that metallic ions can accumulate without wind shear at lower height (90–105 km) as a consequence of the MLT winds leading to the ion drifting downward. We suggest that the turbopause at 90–105 km plays an important role in forming low‐altitude Es layer in the middle‐ and low‐latitude regions. Plain Language Summary: Sporadic‐E layer is an enhanced ionization patch, which can reflect radio wave signals, and plays a significant role in the telecommunication and navigation system. The occurrence of Es layer is inconsecutive and influenced by many factors, such as wind, electric field, and meteor input, which makes the prediction of Es layer very difficult. In this study, we try to investigate the process of the formation of Es layer from electrodynamic theory of ionosphere. Our simulation results demonstrate that the wind shear, a classical theory for the Es layer formation at midlatitude, is not the only mechanism leading to the generation of Es layer, and turbopause at 90–105 km height can provide the concentration location for metallic ions. Key Points: Windshear Theory of sporadic‐E (Es) formation is reexaminedMeteor radar and ionosonde observations show that Es can form at nonwindshear pointsSimulation results show that Es formation can be affected by the turbopause [ABSTRACT FROM AUTHOR]

The deep neural network has made the most advanced breakthrough in almost all 2D image tasks, so we consider the application of deep learning in 3D images. Point cloud data, as the most basic and important form of representation of 3D images, can accurately and intuitively show the real world. The authors propose a new network based on feature fusion to improve the point cloud classification and segmentation tasks. Our network mainly consists of three parts: global feature extractor, local feature extractor and adaptive feature fusion module. A multi‐scale transformation network is devised to guarantee the invariance of the transformation of the global feature, and a residual block is introduced to alleviate the problem of gradient disappearance to enhance the global feature extractor. Based on the edge convolution and multi‐layer perceptron, a local feature extractor is constructed. Finally, an adaptive feature‐fusion module is proposed to complete the fusion of global features and local features. Extensive experiments on point cloud classification and segmentation tasks are carried out to verify the effectiveness of the proposed method. The classification accuracy of the ModelNet40 is 93.6%, which is 4.4% higher than that of the PointNet. Similarly, the segmentation accuracy on the ShapeNet is 85.6%, which is higher than other methods. [ABSTRACT FROM AUTHOR]

Cardiac foreign bodies, especially those with sharp tips, may lead to unpredictable complications, such as penetrating cardiac injuries. Yet there have not been many reports of penetrating cardiac injuries caused by a needle that migrates from the neck to the heart. We herein present a review of such a case, focusing on the dynamic monitoring by perioperative echocardiography. The needle was represented on the monitor as a linear artifact that had penetrated through the ventricular wall and caused increasing pericardial effusion. Fortunately, the needle was successfully removed before it completely entered the right ventricular cavity. In this case, perioperative echocardiography played a significant role in clinical emergency decision making. [ABSTRACT FROM AUTHOR]

An imidazole functionalized metal–organic framework (MOF), [Cu(HL)(H2O)]·(H2O)·(DMA) (HBU‐166, H3L = 4,4′,4″‐(1H‐imidazole‐2,4,5‐triyl)tribenzoic acid, DMA = N,N‐dimethylacetamide) was synthesized and characterized by single‐crystal X‐ray diffraction. HBU‐166 was observed as a two‐dimensional MOF and showed good stability in water, an acidic solution (pH = 4), and an alkaline solution (pH = 9). HBU‐166 exhibited ligand‐based luminescence with a blue shift, which could be attributed to the coordination effect. Moreover, HBU‐166 could be applied to detect nitroaromatic compounds (NACs) and metal ions in water with preferable selectivity and sensitivity. In particular, HBU‐166 could be used as a promising luminescent sensor for picric acid (PA) with enhancement of emission intensity. The mechanism for PA detection likely involved electron transfer and weak interaction between ligand and electron‐deficient of NACs at the beginning to increase the emission intensity. Additionally, HBU‐166 exhibited excellent selectivity in the sensing of 4‐nitrophenol and Fe3+ through fluorescence quenching. [ABSTRACT FROM AUTHOR]

Carbon‐supported NiII single‐atom catalysts with a tetradentate Ni‐N2O2 coordination formed by a Schiff base ligand‐mediated pyrolysis strategy are presented. A NiII complex of the Schiff base ligand (R,R)‐(−)‐N,N′‐bis(3,5‐di‐tert‐butylsalicylidene)‐1,2‐cyclohexanediamine was adsorbed onto a carbon black support, followed by pyrolysis of the modified carbon material at 300 °C in Ar. The Ni‐N2O2/C catalyst showed excellent performance for the electrocatalytic reduction of O2 to H2O2 through a two‐electron transfer process in alkaline conditions, with a H2O2 selectivity of 96 %. At a current density of 70 mA cm−2, a H2O2 production rate of 5.9 mol gcat.−1 h−1 was achieved using a three‐phase flow cell, with good catalyst stability maintained over 8 h of testing. The Ni‐N2O2/C catalyst could electrocatalytically reduce O2 in air to H2O2 at a high current density, still affording a high H2O2 selectivity (>90 %). A precise Ni‐N2O2 coordination was key to the performance. [ABSTRACT FROM AUTHOR]

A novel digital signal processing (DSP) scheme for special‐shaped circular (7,1) modulated signals based on quasi blind carrier phase estimation (QBCPE) is proposed. The results show that applying 0.33‰ overhead QBCPE provides similar performance as 3% training sequence data‐aided equalization of least mean square (LMS) algorithm. [ABSTRACT FROM AUTHOR]

Abstract: Visible light communication (VLC) is an emerging optical wireless communication, which combines lighting and communication simultaneously. In indoor VLC systems, the brightness of LEDs should be dimmed to a certain level to support the illumination function. In this article, we propose a novel dimming control scheme based on Reversed Unipolar Return‐to‐Zero (RURZ) coding and circular (7, 1) modulation. The dimming level is determined by the duty cycle ratio (DCR) of the RURZ codes. Contrary to traditional RZ coding, with the decrease of DCR, the component of high‐level signal in RURZ codes increases and could constantly keep LEDs on. Therefore, when the DCR is smaller, the time that the LED is on keeps longer and the illumination efficiency is higher. A special shaped 8‐QAM modulation scheme called circular (7, 1) is employed to obtain a wider dimming range and higher communication quality for its superiority in operation range and bit error ratio (BER) performance. Furthermore, pulse shaping technology is utilized to suppress the wide spectrum extended by RURZ coding and increase the spectral efficiency (SE) and the data rate. Theoretical analysis and experimental investigation demonstrate that the RURZ coded and circular (7, 1) modulated VLC system could achieve a wide dimming range with high illumination efficiency and high communication speed. An illumination efficiency improvement of 0.63 is successfully achieved at 30% DCR with a data rate of 1.35 GB/s over 1 m free space transmission. [ABSTRACT FROM AUTHOR]

Today, we are observing a transition of science paradigms from the computational science to data-intensive science. With the exponential increase of input and intermediate data, more applications are developed using the MapReduce programming model, which is regarded as an appropriate programming model for analysing large data sets. A MapReduce framework runs its applications on a cluster, where the computing capacity allocated to the applications is limited and may not fill their runtime resource demand. In this case, the Map/Reduce tasks have to wait in a queues, and the applications suffer from a poor performance. This work develops an autonomic resource manager within the Hadoop MapReduce framework. The manager is capable of getting aware of the overloading or under-loading situations with the resources allocated to its user community. For the former, it takes an action of requesting more resources from, for example, the batch system of a High Performance Computing (HPC) cluster or Computing Clouds and integrates the additional resources, in case of acquisition, into the Hadoop MapReduce runtime. For the latter, the manager gives the free resources back to its source. We extended the existing Hadoop MapReduce resource manager to implement the proposed strategy and validated the concept on an HPC cluster with standard benchmark applications. Experimental results show a significant performance gain, for example, an up to 45% improvement in execution time for running multiple applications. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]