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The resampling-free update (RFU) framework avoids discarding the higher-order moment information of the state probability distribution in Gaussian approximation filters. Still, it suffers from the problem of numerical instability and estimation optimality being corrupted caused by non-closed mapping without Gaussian reconstruction. This study proposes a novel robust RFU framework-based cubature Kalman filter. The maximum correntropy criterion is adopted as the optimization cost to exploit the non-Gaussian moments caused by non-closed mapping in RFU. An RFU update is reconstructed based on the square root of a posterior error matrix to improve the numerical stability. In addition, the periodic resampling operation is implemented to mitigate the non-Gaussianity while keeping higher-order moments. The illustrative example demonstrates that the proposed method can improve the estimation robustness and consistency of the RFU framework compared to other state-of-the-art RFU-based filters. • An RFU update is designed based on the square root of a posterior error matrix. • MCC is adopted as optimization criterion to exploit non-Gaussian moments of RFU. • The theoretical performance of the RFU filters is analyzed. [ABSTRACT FROM AUTHOR]

The dislocations are the deep level defects with a negative impact on the multi-crystalline silicon (mc-Si) solar cells. Though potential mechanisms of dislocation formation on the silicon ingot have been studied, few investigations consider the effect of LED hydrogenation on dislocation clusters. In this study, we have explored the influence of hydrogenation on the dislocation clusters of large-area (244.34 ± 0.05 cm2) mc-Si solar cells using the high-intensity infrared LED source. However, applying normal cooling measure to hydrogenation will trigger the instability of the hydrogenation improvement effect due to residual thermal stress, so we proposed an appropriate rapid cooling measure (RCM) followed by hydrogenation and achieved optimized results. The results indicated that electrical properties, minority carrier lifetime, current density, power density and external quantum efficiency were enhanced through LED hydrogenation and RCM, and the degradation of mc-Si solar cells also was significantly suppressed. To estimate the content of dislocations after LED hydrogenation and RCM, we applied the X-ray diffraction techniques to calculate the dislocation density using the full-width at half maximum of the rocking curve at (111), (220), (311), (400) and (331) reflections. The dislocation density of mc-Si PERC solar cells was decreased by 0.12 × 108 cm−2 (±0.02 × 108 cm−2) after LED hydrogenation and RCM. Meanwhile, photoluminescence images also illustrated that LED hydrogenation passivated dislocation clusters as well as impurities and defects gathered by dislocations. Therefore, LED hydrogenation of dislocation clusters is an effective measure to improve the performance of dislocation-containing mc-Si solar cells. [ABSTRACT FROM AUTHOR]

Although the monocrystalline silicon (mono-Si)-passivated emitter and rear contact (PERC) solar cells have achieved incredible efficiency, they still can be further improved by hydrogenation. So the hydrogenation was performed to investigate the improvement of large area (>240 cm2) mono-Si PERC solar cells and estimate the significance of previous light-induced degradation (pre-LID) under a high-intensity infrared (HI-IR) LEDs source platform. Then, the results indicated that the parameters, such as open-circuit voltage (Uoc) and short-circuit current density (Jsc) and fill factor (FF), could be better improved after LED hydrogenation with the execution of the pre-LID. The efficiency of mono-Si PERC solar cells with pre-LID increased by ~0.190 ± 0.005%abs. for 2 min, which was higher than that without pre-LID (0.115 ± 0.005%abs.). Moreover, the results showed that the efficiency of large area mono-Si PERC solar cells with light-induced degradation (LID) treatment after LED hydrogenation only existed a slight degradation of about −0.253 ± 0.005%rel.. Compared with mono-Si PERC solar cells without pre-LID, the efficiency improvement and LID mitigation of mono-Si solar cells with pre-LID was faster and more significant by LED hydrogenation, so that the LED hydrogenation time significantly can shorten from 6 to 2 min. Additionally, the possible presence of a boron-oxygen (BO) model was estimated, and this BO model is susceptible to be activated by the injection of external energy, resulting in more BO defects in the process of pre-LID, so that subsequent hydrogenation rate becomes faster. [ABSTRACT FROM AUTHOR]

The efficiency improvements of large area (244.34 cm2) crystalline silicon solar cells have been receiving significant attention, especially in high-efficiency multi-crystalline silicon (mc-Si) Passivated Emitter and Rear Contact (PERC) cells. The large area boron-doped mc-Si PERC cells were treated with hydrogenation for a different duration based on high-intensity infrared (HI-IR) LEDs of 940 nm. Compared to the boron-doped monocrystalline silicon (mono-Si) PERC cells, different trends of efficiency improvement were displayed after various hydrogenation duration. The results showed that the amplitude of the efficiency improvement was enhanced to the maximum around 8 min but then slowly decreased with the increasing hydrogenation duration. Moreover, we found that the iron-boron (Fe-B) pairs may occupy the dominant role in hindering the improvement of efficiency and the light-induced degradation (LID) after hydrogenation. The trend of efficiency improvement depended on the density of interstitial iron ions (Fe i +) and the formation and dissociation of Fe-B pairs. Therefore, a longer duration of hydrogenation was required for mc-Si PERC cells than for mono-Si PERC cells to enhance the efficiency and suppress the degradation. Additionally, the duration of hydrogenation was significantly shortened to 1 min when the pre-LID was applied, then the appropriate extension of the hydrogenation duration was more conducive to the efficiency improvement of mc-Si PERC cells. • The mc-Si PERC cells required a longer duration for hydrogenation. • The efficiency of mc-Si PERC cells appeared a loss, then gained steadily increase. • The reason for longtime hydrogenation of mc-Si PERC cells was due to Fe-B pairs. • The pre-LID was proposed to improve the efficiency loss and hydrogenation effect. [ABSTRACT FROM AUTHOR]

The texture evolution, crystal orientation-dependent deformation mechanism and mechanical properties of the Mg-5.5Gd-4.4Y-1.1Zn-0.5Zr (wt%) alloy sheet with bimodal grain structure during hot rolling were investigated in this study. The pre-rolled sheet possesses the texture with c-axis randomly distributed in rolling-transverse plane. During the hot rolling deformation, the initial texture is gradually changed to an uncommon texture with c-axis continuously distributed between transverse direction (TD) and normal direction (ND) of the rolled sheet. The formation of the texture is related to the orientation-dependent deformation mechanism of coarse grains. For the coarse grains with c-axis close to rolling direction (RD), {10-12} twinning was identified to be the dominated deformation mechanism. With the activation of twinning, the c-axis of the matrix is reoriented towards ND. For the coarse grains with c-axis near TD, prism slip and kink deformation were figured out as the dominated deformation modes. In early stage of the hot rolling deformation, the c-axis of the grains remains in TD with the activation of prism slip. Afterwards, kink deformation activates and the c-axis of the grains is rotated away from TD towards ND with different degrees. In addition, the mechanical properties of rolled sheets were examined and the results demonstrate that yield strength and tensile strength are gradually improved by rolling deformation. Nevertheless, the improvement of yield strength in RD is much greater than that in TD and a serious yield strength anisotropy is shown in the rolled sheet. The strong yield strength anisotropy derives from the variation of texture strengthening in the RD and TD due to the formation the texture with c-axis continuously distributed between TD and ND. [ABSTRACT FROM AUTHOR]

To address the interference of outliers on the estimation of state and measurement noise covariance matrix, an adaptive maximum correntropy cubature Kalman filter with variational Bayesian approximation over a sliding window is proposed. The multiple kernel size is adjusted for different noise within a reasonable range based on the squared Mahalanobis distance of innovation, which overcomes the excessive convergence problem in the adjustment process. The correntropy matrix is established using the adaptive multiple kernel size to achieve measurement-specific outliers processing. Then the measurement noise covariance matrix is updated as inverse Wishart distribution exploiting the posterior smoothing-based variational Bayesian approximations with correntropy matrix, suppressing the disturbance of measurement outliers to the modification of the measurement noise covariance matrix. Finally, the target tracking simulation and cooperative positioning experiment demonstrate that the proposed method can effectively achieve the robust state estimation with accurate modification of MNCM in the presence of outliers. • Kernel sizes are adaptive without excessive convergence problems. • Outliers' measurement-specific is realized by correntropy with kernel sizes. • MNCM is modified under outliers by VB combining correntropy matrix. [ABSTRACT FROM AUTHOR]

Genetic polymorphisms in mTOR gene may be associated with cancer risk and clinical outcomes of cancer patients by affecting mTOR gene expression or its activation. However, inconsistent results have been reported. The aim of this study is to systematically evaluate the association between mTOR polymorphisms (rs2295080, rs2536 and rs11121704) and cancer risk as well as clinical outcome by a meta-analysis. We identified 10 eligible studies and extracted data by two investigators. Based on dominant and recessive models, odds ratio (ORs) and 95% confidence intervals (CIs) were calculated by using Stata, version 11 to evaluate the association strength. Our meta-analysis results showed that the wild genotype TT of rs2295080 polymorphism was associated with increased cancer risk under dominant model (OR = 1.24, 95%CI: 1.12–1.36, p<0.0005) in Chinese but not with clinical outcome parameters, while the TT genotype of rs11121704 was associated with poor clinical outcome parameters (OR = 1.53, 95%CI: 1.01–2.32, p = 0.044), such as death, metastasis and resistance to chemotherapy. However, rs2536 may not influence cancer susceptibility. In conclusion, this meta-analysis indicated the common polymorphisms in mTOR gene might be genetic risk factors for the carcinogenesis and clinical outcomes of cancer patients. However, further investigation on large population and different ethnicities are warranted. [ABSTRACT FROM AUTHOR]

• A new unsupervised fusion network by integrating a Fusion Sub-Net is proposed. • A novel loss function is performed to address fusion problems. • The trained network on polarization data works well on other fusion tasks. Polarization image fusion aims to integrate intensity and degree of linear polarization images into one with more details, which is beneficial to improve the ability of targets detection under complex background. The fusion strategies in conventional methods are designed in a hand-crafted way and not robust to different fusion tasks. In this paper, we propose a novel and deep network to address the polarization image fusion issue with self-learned strategy. The network consists of Encoder, Fusion, and Decoder layers. Feature maps extracted by Encoder are fused, then fed into Decoder to generate fused images. Besides, a novel loss function is adopted to train the network in an unsupervised way, without ground truth of fused images. To verify the advantage, the network trained on polarization images is also used to infrared and visible images fusion, and multi-focus image fusion. Experimental results showed that our method outperforms several state-of-the-art methods in terms of visual quality and quantitative measurement. The proposed fused method can be applied in the military and civilian fields such as camouflage and hidden targets detection, medical diagnosis, and environmental monitoring. [ABSTRACT FROM AUTHOR]

Light injection and cooling conditions can induce some differences in the temperature-raising time of multi-crystalline silicon (mc-Si) solar cells. Through real-time tracking and monitoring of sample surface temperature, the temperature-raising steps for achieving the optimum efficiency improvement and degradation mitigation were optimized and modified. Then the corresponding hydrogenation treatments under a high-intensity infrared LEDs source were carried out based on improved steps. The results indicated that the optimal temperature-raising time should be manipulated at around 60 s and then followed by a 2-min hydrogenation treatment. Furthermore, the temperature-raising process should keep the temperature rising continuously without interruption or temperature drop. However, excessive thermal treatment time damaged the formation of defect precursors and extended the hydrogenation time. Moreover, the Fourier Transform Infrared spectrum curves illustrated that the peak intensity of the Si–H bonds treated at the 60-s temperature-raising time was more significant than that of other temperature-raising time treatments. • Manipulated temperature-raising steps bring more efficient hydrogenation. • 60-s temperature-raising time and 2-min hydrogenation was optimum. • Excessive temperature-raising time damaged the formation of defect precursors. • 60-s temperature-raising time promoted the best peak intensity of Si–H bond. [ABSTRACT FROM AUTHOR]

Tunnel Oxide Passivated Contact (TOPCon) solar cells have received widespread attention in recent years, especially in improving conversion efficiency. This paper investigated the impact of hydrogenation technology using photon-injection (HPI) and electron-injection (HEI) processes on TOPCon solar cells, highlighting the higher improvement effect and broader application scope of HPI compared to HEI. In TOPCon cells, several methods are available to prepare the tunneling oxide layer, such as plasma oxidation (PO) and indirect thermal oxidation (TO). The research results indicated that significant improvement differences could be observed when utilizing the HEI treatment for TOPCon solar cells prepared by PO and TO methods, with values of 0.133% abs. and −0.039% abs. , respectively. Meanwhile, HPI treatment induced a more significant efficiency improvement for these two types of cells, and the increase in efficiency is 0.247% abs. and 0.244% abs. , respectively. The experimental results demonstrated that the passivation effect for TOPCon solar cells prepared by PO and TO methods remained almost the same under the HPI treatment, and the improvement effect is less dependent on the tunnel oxidation technique used. Thus, the different passivation effects between HPI and HEI were further investigated, and the reason for the difference was attributed to the charge states and concentrations of hydrogen and non-equilibrium carriers during the hydrogenation. The results provided an improved scheme for enhancing the efficiency of TOPCon solar cells, shedding light on the role of HPI and HEI in the passivation process. This work brings further insights to TOPCon solar cells. • Optimum parameters of HPI and HEI are established for TOPCon solar cells. • HPI significantly improves PCE of TOPCon solar cells and is more universal than HEI. • TO or PO method significantly affects the HEI effectiveness of TOPCon solar cells. • The hydrogenation effect depends on the charge states and concentrations of hydrogen. [ABSTRACT FROM AUTHOR]

Perovskite Solar Cells (PSCs) have drawn tremendous attentions from scientific community due to their advantages of high efficiency and low-cost. However, the mechanism of photoelectron generation is unclear because the light field distribution is difficult to be quantitively characterized by conventional methods. The Optical Transfer Matrix Method (OTMM) has been applied in organic devices based on p-n structures. We have applied different materials as back electrode to examine the light propagation inside of planar p-i-n solar cells with regular structure (Glass/ITO/SnO x /CH 3 NH 3 PbI 3 /Spiro-OMeTAD/Back electrode). The simulations were performed by using OTMM to carry out the optical field modeling of simulated solar cells in visible-near infrared (NIR) range. Among the simulation models, it has been found that perovskite solar cells based on sliver electrode has highest light intensity oscillation and faster charge generation rate. But sliver electrode has lower stability because the iodine can diffuse to the interface and form AgI with the assist of NIR-induced thermal effect. By contrast, the independent graphene electrode has disadvantages of interlayer conductivity and transparency. Based on the simulation result, we recommend that the graphene can be applied as a buffer layer between perovskite and sliver electrode instead of being an independent electrode. • The coherent/incoherent light propagation were both taken account into the OTMM analysis of solar cells. • The light filed intensity of near-infrared light was oscillated at the interface of perovskite/HTL which can decrease the thermal stability for PSCs. • The charge extraction was obviously lower because the light can transmit from the graphene electrode rather than reflected back to perovskite active layer • The graphene can be applied as a buffer layer between perovskite and sliver electrode instead of being an independent electrode which can promote both efficiency and stability. [ABSTRACT FROM AUTHOR]

Background: Coronavirus disease 2019 (COVID-19) share similar symptoms with influenza A (IA), but it is more worthwhile to understand the disparities of the two infections regarding their clinical characteristics on admission.Methods: A total of 71 age-matched pediatric IA and COVID-19 patient pairs were formed and their clinical data on admission were compared.Results: Fever, cough, nasal congestion and nausea/vomiting were the most common symptoms on admission for both infections but occurred less often in COVID-19. The IA patients were more likely to have lower-than-normal levels of lymphocyte count and percentage and to have higher-than-normal levels of activated partial thromboplastin time, prothrombin time, serum C-reactive protein, and serum procalcitonin, while the COVID-19 patients had higher odds of having lower-than-normal levels of neutrophil count and percentage.Conclusions: This study suggests that influenza A is more symptomatic than COVID-19 for children and might be an overall more severe infection at the time of admission. [ABSTRACT FROM AUTHOR]

The research on the hydrogen passivation process for silicon solar cells has been developed for a long time. Recently, researchers have investigated the use of lasers as light sources. It has been found that hydrogen passivation technology can improve the minority carrier lifetime and passivate some impurities and defects in silicon solar cells. In this paper, a hydrogenation platform for silicon solar cells based on high intensity infrared LEDs of 940 nm was built. After a number of comparative experiments, electrical characteristics, photo-luminescence images, and light beam induced current were applied before and after hydrogenation to distinguish the passivation effect. It was found that the effect of hydrogen passivation on monocrystalline boron-doped passivated emitter and rear contact (PERC) solar cells by using infrared LEDs as the light source was satisfactory under the condition of suitable light intensity and temperature. It has a remarkable effect on improving the electrical characteristics and increasing the efficiency of monocrystalline boron-doped PERC solar cells based on high intensity infrared LEDs of 940 nm. [ABSTRACT FROM AUTHOR]

Anisotropy photoresponse can be effectively achieved based on gradient organic heterojunction. However, the gradient heterojunction has yet been studied due to the complicated process and great random error inside. Especially in the field of transient optics, the light on/off in femto/picosecond range is vitally important for high-speed optical systems, such as application in fiber communications. In this paper, the wedge-structured organic heterojunction was fabricated based on molecular beam epitaxy. The devices were combined with both wedge-structured heterojunction and half-wave plate. When the probe light was tuned to 2.0 eV, a narrow passband was instantly observed once the pump and probe light were perpendicular to each other. The photoresponse can be achieved within 0.84 ps which can tune the optical signals on and off in transient optics. The results have demonstrated an exciting application in photo sensing. [ABSTRACT FROM AUTHOR]

Introduction: Heterogeneous MRI manifestations restrict the efficiency and consistency of neuroradiologists in diagnosing hypoxic-ischemic encephalopathy (HIE) due to complex injury patterns. This study aimed to develop and validate an intelligent HIE identification model (termed as DLCRN, deep learning clinical-radiomics nomogram) based on conventional structural MRI and clinical characteristics. Methods: In this retrospective case-control study, full-term neonates with HIE and healthy controls were collected in two different medical centers from January 2015 to December 2020. Multivariable logistic regression analysis was implemented to establish the DLCRN model based on conventional MRI sequences and clinical characteristics. Discrimination, calibration, and clinical applicability were used to evaluate the model in the training and validation cohorts. Grad-class activation map algorithm was implemented to visualize the DLCRN. Results: 186 HIE patients and 219 healthy controls were assigned to the training, internal validation, and independent validation cohorts. Birthweight was incorporated with deep radiomics signatures to create the final DLCRN model. The DLCRN model achieved better discriminatory power than simple radiomics models, with an area under the curve (AUC) of 0.868, 0.813, and 0.798 in the training, internal validation, and independent validation cohorts, respectively. The DLCRN model was well calibrated and has clinical potential. Visualization of the DLCRN highlighted the lesion areas that conformed to radiological identification. Conclusion: Visualized DLCRN may be a useful tool in the objective and quantitative identification of HIE. Scientific application of the optimized DLCRN model may save time for screening early mild HIE, improve the consistency of HIE diagnosis, and guide timely clinical management. [ABSTRACT FROM AUTHOR]

Abstract In this work, deformation behavior of an extruded Mg-Zn-Gd-Y-Zr alloy sheet, including mechanical anisotropy and tension-compression asymmetry, were investigated by conducting tension and compression experiments along different directions. Coupling with the strong texture, the role of long-period stacking ordered (LPSO) phases in the deformation behavior was analyzed based on the microscopic plastic deformation theory. The results showed that LPSO phases with different morphologies played different roles in deformation behavior of the strong textured Mg-Zn-Gd-Y-Zr alloy sheet: (i) the irregular-shaped LPSO phases distributed along extrusion direction (ED) brought anisotropic fiber reinforcement and exacerbated the mechanical anisotropy; (ii) the needle-like LPSO phases filled in the grain interior hindered the propagation of twinning boundaries and decreased the tension-compression asymmetry. The results may provide valuable references for the manufacturing of large size Mg/LPSO alloys with low mechanical anisotropy and tension-compression asymmetry, hence making them better to meet the growing need of engineering application. [ABSTRACT FROM AUTHOR]

A large size Mg-1.2Zn-3.4Y-4.7Gd-0.5Zr (wt%) alloy sheet was manufactured by semi-continuous casting, homogenization and hot extrusion, in which the microstructures were systematically examined. The results showed that: (i) During homogenization, the generation of 14H LPSO phase was mainly achieved by two phase transition processes of “Mg 5 (Gd,Y,Zn) phase → 14H LPSO phase” and “18R LPSO phase → 14H LPSO phase”. (ii) During extrusion, the evolution of LPSO phases with various morphologies was driven by severe deformation and dynamic recrystallization (DRX). Under severe deformation, the 14H LPSO phases in homogenized alloy were broken down to fragments with various sizes. Under the influence of DRX, the deformation defects of small LPSO fragments were fully eliminated and formed the “sandwich-like” LPSO phase. While the deformation defects of coarse LPSO fragments were less eliminated and formed the “irregular-shaped” LPSO phase. Meanwhile, due to the decreased solubility of Zn, Y and Gd in the extruded alloy matrix, the solution elements of Zn, Y and Gd were impelled to precipitate at the scattering arranged stacking faults (SFs) and formed the “needle-like” LPSO phase. It is found that the gliding of Shockley partial dislocation(s) on basal plane was structurally needed during the precipitation of needle-like LPSO phase. [ABSTRACT FROM AUTHOR]

In order to further improve the photovoltaic conversion efficiency of tunnel oxide passivated contact (TOPCon) solar cells, the hydrogenation with electron injection (HEI) technique on TOPCon solar cells with different processes for preparing tunneling SiOx layers was investigated. The experimental results showed that the conversion efficiency enhancement of TOPCon solar cells with a tunneling SiOx layer prepared by a N2O plasma oxidation method (PO method) was lower than that of the cells prepared by an indirect thermal oxidation method (TO method) under the same HEI treatment conditions. Further studies proved that the improvement effect after HEI treatment was closely related to the denseness of the tunneling SiOx layer: HEI treatment for TOPCon solar cells with a low dense tunneling SiOx layer (TO method) requires higher temperature, higher current, and longer time to achieve a better improvement, while the HEI parameters of cells with a high dense tunneling oxide layer (PO method) need to be readjusted. By optimizing the HEI parameters for cells prepared by the PO method, the power conversion efficiency (PCE) of the cells was finally improved by 0.098%abs. The PCE was improved from the original negative growth to a level close to that of the TOPCon cells prepared by the TO method. This result provided an improved process flow to further increase the efficiency of TOPCon solar cells. [ABSTRACT FROM AUTHOR]

Objective: To compare the performance of the EAONO/JOS, STAMCO, and ChOLE Cholesteatoma Staging Systems in prognostic evaluation of children acquired middle ear cholesteatoma after primary surgery and identify the other factors that could predict cholesteatoma recidivism. And the correlation between the staging and the recidivism of cholesteatoma after grouping according to operation was evaluated. Methods: A total of 123 ears of 118 patients that underwent surgery for primary cholesteatoma from November 2008 to May 2020 were included in this retrospective study, and then classified and staged according to the EAONO/JOS, STAMCO, and ChOLE cholesteatoma staging system, respectively. Each indicator involved in the system above was analyzed separately to evaluate its prognostic value for cholesteatoma recidivism. Results: The type of surgical procedure performed (P = 0.020) was shown to be associated with cholesteatoma recidivism. Cholesteatoma location the supratubal recess (S1) (P = 0.026, HR = 3.614, 95% CI 1.137, 7.945), and the sinus tympani (S2) (P = 0.004, HR = 4.208, 95% CI 1.574, 11.250) were shown to be significantly associated with disease recidivism. When focusing on the CWU operation group, ossicular chain status in STAMCO stage (P = 0.043) and in the ChOLE stage (P = 0.018) were significantly associated with cholesteatoma recidivism. The results had shown no association between the three stages and cholesteatoma recidivism in the CWD and endoscopic surgery groups. Conclusions: Based on our study, the EAONO/JOS, STAMCO, and ChOLE Classifications have limited value in predicting cholesteatoma recidivism, in acquired middle ear cholesteatoma in children. Adding the pathological status of the ossicular chain may be useful for predicting the recidivism of cholesteatoma. Additional validation studies are entailed to definitively assess the clinical utility of these classifications. [ABSTRACT FROM AUTHOR]

In this study, it was found that infrared-assisted annealing (IAA) was a novel and rapid method for growing of high-qualitied MAPbI3 films. Compared to traditional thermal annealing, this new strategy combined high-intensity infrared photon flux into annealing process, which achieved the high-qualitied MAPbI3 film with large crystalline grains and less surface defects. The reaction between MAI and PbI2 was characterized by confocal laser scanning and X-ray diffraction, which showed the addition of the infrared photons accelerated the reaction of the crystal, and the growth process of perovskite films with the increase of photon number is revealed. The simulation results revealed that infrared photons reduced the critical-free energy of crystallization of MAI and PbI2, leading to the rapid growth of grains. Fabricated perovskite devices based on MAPbI3 film obtained by this strategy produced optimized power conversion efficiency over 17% under only 5 min of IAA treatment, which increased by 2.6% compared to the thermal annealing. The efficiency improvement mainly attributed to better crystallinity, larger crystal grains under the IAA treatment, which had provided a new strategy for the future industrial production of perovskites. [ABSTRACT FROM AUTHOR]

The rate of early misdiagnosis in patients with nodular fasciitis of the ear is high. To provide a basis for clinical diagnosis and treatment, we aimed to summarise the clinical manifestations, imaging results, pathological findings, treatment strategies, and postoperative follow-up results for three cases of paediatric nodular fasciitis (two girls, one boy) treated in the Department of Otorhinolaryngology, Head and Neck Surgery, at Beijing Children's Hospital of Capital Medical University from 2018 to 2020. The average age at diagnosis was 24 months. Lesions occurred in the left ear in two cases and right ear in one case. All patients had a history of biopsy before surgery. Rapid growth was observed following biopsy in two patients, and anti-inflammatory treatment was ineffective in all three cases. Fluorescence in situ hybridisation analysis of ubiquitin-specific peptidase 6 (USP6) was performed in two of the three cases, with positive results. The lesions exhibited hypo-intensity or iso-intensity on T1-weighted magnetic resonance imaging (MRI) and heterogeneous hyper-intensity on T2-weighted MRI. "Fascial tail" signs were observed on imaging in all cases. Surgical resection was performed in all cases. Intact ear appearance was observed at follow-up, and there were no cases of recurrence. Conclusion: Combining clinical features with imaging findings may improve the accuracy of preoperative diagnosis in patients with nodular fasciitis. In addition to pathological findings, genetic testing for USP6 may aid in diagnosis. The final diagnosis should be based on comprehensive assessment. Complete surgical resection can prevent recurrence. What is Known: • Paediatric NF around the ear is rare and is easily misdiagnosed as other inflammatory masses that have a higher incidence in children. • Most previous reports of NF were case reports. What is New: • Combining clinical and imaging findings with genetic testing for USP6 rearrangement may improve the accuracy of preoperative diagnosis in patients with NF. Nonetheless, the final diagnosis should be based on comprehensive assessment. • The present paper is significant in that it represents the only report of three cases of ear NF in children with a complete medical history and prognosis. [ABSTRACT FROM AUTHOR]

Background Children and older adults with coronavirus disease 2019 (COVID-19) display a distinct spectrum of disease severity yet the risk factors aren't well understood. We sought to examine the expression pattern of angiotensin-converting enzyme 2 (ACE2), the cell-entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the role of lung progenitor cells in children and older patients. Methods We retrospectively analyzed clinical features in a cohort of 299 patients with COVID-19. The expression and distribution of ACE2 and lung progenitor cells were systematically examined using a combination of public single-cell RNA-seq data sets, lung biopsies, and ex vivo infection of lung tissues with SARS-CoV-2 pseudovirus in children and older adults. We also followed up patients who had recovered from COVID-19. Results Compared with children, older patients (>50 years.) were more likely to develop into serious pneumonia with reduced lymphocytes and aberrant inflammatory response (P =.001). The expression level of ACE2 and lung progenitor cell markers were generally decreased in older patients. Notably, ACE2 positive cells were mainly distributed in the alveolar region, including SFTPC positive cells, but rarely in airway regions in the older adults (P <.01). The follow-up of discharged patients revealed a prolonged recovery from pneumonia in the older (P <.025). Conclusions Compared to children, ACE2 positive cells are generally decreased in older adults and mainly presented in the lower pulmonary tract. The lung progenitor cells are also decreased. These risk factors may impact disease severity and recovery from pneumonia caused by SARS-Cov-2 infection in older patients. [ABSTRACT FROM AUTHOR]

Summary: A predetermined relationship between open circuit voltage (OCV) and state of charge (SoC) is the premise of model‐based SoC estimation algorithms. Commonly used OCV tests to obtain the offline OCV‐SoC curves include the low current OCV test and the incremental OCV test. In this paper, in addition to comparing the low current OCV test with the incremental OCV test which applies 0.5 C current‐rate, the incremental OCV tests which apply 0.2, 0.3, and 1 C current‐rates are compared as well. Moreover, from the perspective of test accuracy and test duration, the optimal relaxation time for incremental OCV test is investigated. The recursive least squares method with a forgetting factor (FFRLS) is used to identify the parameters of the battery model, and the adaptive extended Kalman filter (AEKF) is employed to estimate SoC. The results indicate that the SoC estimator which applies the OCV‐SoC curve obtained from the 0.5 C incremental OCV test performs better than other estimators at 25°C and 45°C. But at 0°C, the SoC estimator which applies the OCV‐SoC curve obtained from the 0.2 C incremental OCV test has the best estimation performance. In addition, 3 h relaxation time is the optimal choice at 25°C and 45°C, while 4 h relaxation time is recommended at 0°C. [ABSTRACT FROM AUTHOR]

P-type multi-crystal (mc-Si) solar cells are facing relative weaker competitiveness compared to mono-crystal silicon solar cells due to the efficiency improvement bottleneck. To further enhance the efficiency of p-type mc-Si solar cells, we have systematically investigated the technology of hydrogenation with electron injection (HEI) on p-type mc-Si solar cells with different power conversion efficiency (PCE) grades. Experimental results manifested that the efficiency promotion of cells with higher efficiency (HE) was lower compared to that of lower efficiency (LE) cells under the same HEI processing condition, whether for conventional or passivated emitter and rear cells. Further investigations were carried out to prove that the effectiveness of HEI treatment was closely related to the concentration of both available hydrogen and defect in the bulk of solar cells. This highlighted that the lower concentration of available hydrogen was more helpful for HE cells to improve the electrical performances, which was contrary to LE cells due to the different distribution of defects in the bulk. Besides, programing analysis was implemented to optimize the HEI treatment scheme of HE cells, and the PCE was finally improved by 0.63%rel. ± 0.05%. This result provided an improved technological process to further improve the efficiency gains in the production process, where a classification method was introduced according to the efficiency distribution before HEI treatment. The proposed method can distribute solar cells into appropriate grades to avoid wasting resources in mass production. [ABSTRACT FROM AUTHOR]

Background: Chest computed tomography (CT) findings in children with coronavirus disease 2019 (COVID-19) have been rarely reported in a comprehensive and systematic manner. Objective: We investigated the chest CT findings in children with COVID-19, and explored the differences in these findings between symptomatic patients and asymptomatic patients. Materials and methods: Demographic findings, clinical characteristics, duration of hospital stay and viral shedding, and chest CT findings in 201 children infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) were retrospectively analyzed from January 15 to March 20, 2020, and divided into two groups: symptomatic group (n=136) and asymptomatic group (n=65). Chi-square test and Student's t-test were used for statistical analysis. Results: Symptomatic patients were mainly young children ≤3 years old (54/63, 86%),while asymptomatic patients were mainly children ≥ 6 years old (51/111, 46%). Fever (41%) and cough (41%) were the most common symptoms. Overall, 119/201 (59%) patients had chest CT findings, and symptomatic patients accounted for 82% (98/119). The CT findings presented as bilateral multiple lesions (60/119, 50.4%), ground-glass opacities (83/119, 70%) and/or consolidation (44/119, 37%) with a peripheral and subpleural distribution (62/83, 75%). Fifteen of 87 (7.2%) patients with lung lesions showed complete lesion absorption, and 42/87 (48%) improved within a mean of 9.1 (standard deviation [SD] 3.2) days. The mean duration of viral shedding was 8.7 (SD 4.9) days. Pleural effusion was very rare. No lymphadenopathy was found in either group. Conclusion: Symptoms associated with pulmonary involvement were most common in infants and young children. The lung lesions of most patients were absorbed and improved in about 9 days. [ABSTRACT FROM AUTHOR]

Background: Acute kidney injury (AKI) is a common complication of critically ill adult patients with COVID-19. However, currently, no studies investigate kidney impairment in children with COVID-19. We investigated incidence and treatment of AKI in pediatric patients with COVID-19 in Wuhan Children's Hospital during the early stages of the COVID-19 pandemic and discuss possible mechanisms of AKI related to SARS-CoV-2 infection. Methods: By extracting data from electronic medical records, we conducted a retrospective observational study of kidney involvement in confirmed pediatric COVID-19 cases in Wuhan Children's Hospital during the coronavirus outbreak, from January 24 to March 20, 2020. Clinical presentations, clinical courses, laboratory findings, and medical interventions are described below. Results: Among 238 confirmed COVID-19 cases, only three were critically ill and needed intensive care unit (ICU) admission. All three developed AKI, but AKI was not detected in any non-critically ill patients outside the ICU. Two of the three patients with AKI had prodromal gastrointestinal symptoms. Significantly elevated interleukin-6 (IL-6) levels and complement activation were observed in these patients with AKI. The three patients with AKI were treated with plasma exchange (PE) and continuous kidney replacement therapy (CKRT), resulting in one complete recovery, one partial recovery, and one mortality due to critical illness. Conclusions: Critically ill children with COVID-19 may develop AKI, especially following prodromal gastrointestinal symptoms. An inflammatory storm and complement-mediated injury may underlie AKI development in children with COVID-19. Our study supports implantation of PE and CKRT in management of critically ill patients with AKI. [ABSTRACT FROM AUTHOR]

Background: The new emerging coronavirus disease 2019 (COVID-19) overall shares similar symptoms with other common respiratory viral infections. We aimed in this study to compare COVID-19 and human adenovirus (HAdV) infections in pediatric patients regarding the frequencies of major clinical symptoms and the potential disparities in laboratory and imaging parameters. Methods: Following a case–control-like design, we built 72 age-matched pediatric COVID-19 and HAdV patient pairs. Their early symptoms and laboratory and imaging characteristics were then retrieved and compared. Results: Fever and cough were the most common symptoms for both infections but were seen more often in HAdV than in COVID-19 patients (92% vs. 66% and 60% vs. 18%, respectively). Compared with COVID-19 patients, children with HAdV infection had statistically significantly higher values of neutrophil count, neutrophil percentage, activated partial thromboplastin time, prothrombin time, lactate dehydrogenase, C-reactive protein, procalcitonin but lower values of lymphocyte percentage, total bilirubin, potassium and sodium. Thoracic computed tomography also revealed more anomalies in HAdV patients than in COVID-19 patients (95% vs. 67%). Conclusions: COVID-19 is an overall less symptomatic and less severe infection at admission compared to HAdV respiratory infection in pediatric population. [ABSTRACT FROM AUTHOR]

In this study, the extruded Mg-6.9Gd-3.2Y-1.5Zn-0.5Zr (wt%) alloy was annealed at 693 K for 1–120 h, evolution of the long-period stacking ordered (LPSO) phases under elevated temperature and their effect on the recrystallization behavior were investigated. Initial microstructure of the extruded alloy consists of coarse deformed grains containing thin plate-shaped 14H-LPSO phase and fine recrystallized grains containing lamellar metastable phase. During annealing, deformed grains are gradually consumed by growing recrystallized grains, accompanied by dissolution of the LPSO phase in the former. Meanwhile, lamellar metastable phase within recrystallized grains transforms into thin plate-shaped 14H-LPSO phase, and simultaneously grows along the basal plane and thickens along the c -axis direction. Migration of recrystallized grain boundary is hindered by the LPSO phase in deformed grains. The hindrance is more significant along the c -axis of LPSO phase due to the remaining Mg matrix between LPSO phase and recrystallized grain boundary. While parallel to the basal plane of LPSO phase, the LPSO phase directly contacts recrystallized grain boundary, and the hindrance is weakened. Besides, the LPSO phase formed in recrystallized grains can also restrict the migration of grain boundary. • Evolution of LPSO phase during annealing was studied considering recrystallization. • LPSO phases in deformed and recrystallized grains hinder grain boundary migration. • Interface structure between LPSO and recrystallized grain affects degree of hindrance. [ABSTRACT FROM AUTHOR]

In this study, multi-directional forging (MDF) experiments were conducted to a homogenized Mg-2.36Y-0.98Zn (at%) alloy containing long period stacking ordered (LPSO) phase. Microstructure evolution of the MDFed alloys with different forging passes were systematically investigated, corresponding microhardness development was also concerned. The results revealed that grain refinement, texture weakening and DRX development during MDF were closely relevant to fragmentation of LPSO phase. It was also found that development of average microhardness and mechanical heterogeneity of the MDFed alloys can be attributed to the competition and balance of work hardening, grain refinement and DRX softening. Furthermore, LPSO-related deformation and dynamic recrystallization (DRX) behaviors such as (i) kink-aided DRX (KDRX, this concept was firstly nominated in this study); (ii) particle stimulated nucleation mechanism (PSN) and (iii) pinning effect on DRX nucleus were thoroughly discussed, which should help to understand the unique microstructure evolution of LPSO-containing Mg alloys, and thus offer certain enlightenment for manufacturing LPSO-strengthened Mg alloys with excellent mechanical property. [ABSTRACT FROM AUTHOR]

Phase unwrapping is a very important step in fringe projection 3D imaging. In this paper, we propose a new neural network for accurate phase unwrapping to address the special needs in fringe projection 3D imaging. Instead of labeling the wrapped phase with integers directly, a two-step training process with the same network configuration is proposed. In the first step, the network (network I) is trained to label only four key features in the wrapped phase. In the second step, another network with same configuration (network II) is trained to label the wrapped phase segments. The advantages are that the dimension of the wrapped phase can be much larger from that of the training data, and the phase with serious Gaussian noise can be correctly unwrapped. We demonstrate the performance and key features of the neural network trained with the simulation data for the experimental data. [ABSTRACT FROM AUTHOR]

A Mg–Zn–Y alloy containing long period stacking ordered (LPSO) phases was compressed at temperatures ranging from 623 K to 773 K and strain rates ranging from 0.001 s−1 to 1 s−1. The role of LPSO phase in dynamic recrystallization (DRX) was emphatically studied. The results revealed that: (i) the area filled with kinked LPSO phase is found as potential site favors the initiation of DRX at lower temperatures. (ii) Fragmentation of LPSO phase at initial grain boundaries significantly improves the DRX process via particle stimulated nucleation (PSN) mechanism. (iii) Boundary migration of DRX grains is frequently pinned by LPSO phase at elevated temperature. Understanding the role of LPSO phase in DRX may shed light on manufacturing of Mg–Zn–RE alloys with excellent mechanical property and good corrosion resistance. • Kinked areas were found as potential sites that favorable for initiating DRX. • Fragmentation of LPSO phase improved DRX at initial grain boundary. • Boundary migration of DRX grains were pinned by LPSO phase. [ABSTRACT FROM AUTHOR]

Two interaction modes between kinking and { 10 1 ‾ 2 } twinning in a Mg–Zn-Gd alloy containing long period stacking ordered (LPSO) phase are thoroughly investigated: (i) when kinking forms prior to twinning, twins concomitantly nuclear at kink boundaries (KBs) and twinning propagation is frequently restricted by two adjacent KBs. By contrast, (ii) when twinning forms prior to kinking, kink deformation locally breaks the twins' theoretical misorientation to their adjacent matrixes, during which basal slip plays a vital role in accommodating the asynchronous deformation between kinking and twinning. [ABSTRACT FROM AUTHOR]

• Machine learning approach for PD investigation. • Multi-frequency based machine learning in PD. • Frequency specificities of ALFF maps in PD. The application of resting state functional MRI (RS-fMRI) in Parkinson's disease (PD) was widely performed using standard statistical tests, however, the machine learning (ML) approach has not yet been investigated in PD using RS-fMRI. In current study, we utilized the mean regional amplitude values as the features in patients with PD (n = 72) and in healthy controls (HC, n = 89). The t -test and linear support vector machine were employed to select the features and make prediction, respectively. Three frequency bins (Slow-5: 0.0107–0.0286 Hz; Slow-4: 0.0286–0.0821 Hz; conventional: 0.01–0.08 Hz) were analyzed. Our results showed that the Slow-4 may provide important information than Slow-5 in PD, and it had almost identical classification performance compared with the Combined (Slow-5 and Slow-4) and conventional frequency bands. Similar with previous neuroimaging studies in PD, the discriminative regions were mainly included the disrupted motor system, aberrant visual cortex, dysfunction of paralimbic/limbic and basal ganglia networks. The lateral parietal lobe, such as right inferior parietal lobe (IPL) and supramarginal gyrus (SMG), was detected as the discriminative features exclusively in Slow-4. Our findings, at the first time, indicated that the ML approach is a promising choice for detecting abnormal regions in PD, and a multi-frequency scheme would provide us more specific information. [ABSTRACT FROM AUTHOR]

Background: Compared to adults, there are relatively few studies on COVID-19 infection in children, and even less focusing on the unique features of COVID-19 in children in terms of laboratory findings, locations of computerized tomography (CT) lesions, and the role of CT in evaluating clinical recovery. The objective of this study is to report the results from patients at Wuhan Children's Hospital, located within the initial center of the outbreak.Methods: Clinical, imaging, and laboratory data of 76 children were collected retrospectively and analyzed with the Fisher exact test and Cox regression statistical methods.Results: Among 50 children with a positive COVID-19 real-time reverse-transcriptase polymerase chain reaction (PCR), five had negative PCR results initially but showed positive results in subsequent tests. Eight (16%) patients had lymphopenia, seven (14%) with thrombocytopenia, four (8%) with lymphocytosis, two (4%) with thrombocytosis, ten (20%) with elevated C-reactive protein, four (8%) with hemoglobin above, and six (12%) with below standard reference values. Seven (14%) of the 50 had no radiologic evidence of disease on chest CT. For the 43 patients who had abnormal CT findings, in addition to previously reported patterns of ground-glass opacity (67%), local patchy shadowing (37%), local bilateral patchy shadowing (21%), and lesion location of lower lobes (65%), other CT features include that an overwhelming number of pediatric patients had lesions in the subpleural area (95%) and 22 of the 28 lower lobe lesions were in the posterior segment (78%). Lesions in most of the 15 patients (67%) who received chest CT at discharge were not completely absorbed, and 26% of these pediatric patients had CT lesions that were either unchanged or worse.Conclusions: There were a few differences between COVID-19 children and COVID-19 adults in terms of laboratory findings and CT characteristics. CT is a powerful tool to detect and characterize COVID-19 pneumonia but has little utility in evaluating clinical recovery for children. These results oppose current COVID-19 hospital discharge criteria in China, as one requirement is that pulmonary imaging must show significant lesion absorption prior to discharge. These differences between pediatric and adult cases of COVID-19 may necessitate pediatric-specific discharge criteria. [ABSTRACT FROM AUTHOR]

The effect of grain size on micro-void evolution and further macroscopic fracture in an austenite steel 316LN was studied through a series of experiments together with the full-field crystal plasticity finite element method (CPFEM) simulations. To probe the grain size effect on void behaviors, macroscopic tensile tests and microscopic fractography characterizations were conducted for samples with different grain sizes. A hierarchy modeling approach based on CPFEM was adopted to quantify the gran size effect accordingly. Authentic boundary conditions were enforced on the high-resolved representative volume elements (RVEs) with realistic grain structures and voids. The simulation results demonstrate that the deformation heterogeneity and the scatter of void growth increase with grain size. Via the quantitative analysis of the void dimension, an extended void growth model involving the effect of grain size was proposed on the basis of the Rice and Tracey model. The extended model adopts the Gaussian distribution to describe the non-uniform void growth induced by the grain-scale deformation heterogeneity and manifests the increase of void size deviation with grain size. The variation of void growth with grain size further leads to a transition of fracture modes. For the fine grain sample, coalescence of densely distributed voids dominates the fracture initiation, and the total void volume fraction thus plays a key role; For the coarse grain sample, however, the growth and coalescence of individual large void are critical for fracture occurrence. With the grain size affected void behavior, the ductility of the material is also shown to be grain size dependent. This study thus advances the comprehensive understanding of the micro-mechanics of ductile fracture and the relationship between microstructure and the macroscopic fracture behavior. • Identify the grain size effect on void behavior via experiments and full-field CP modeling. • Deformation and void size distribution become more uneven as grain size is increased. • An extended void growth model involving the effect of grain size was proposed. • Explain different ductile fracture mechanisms related to grain size. • Identify the relationship between ductility and grain size. [ABSTRACT FROM AUTHOR]

The hot deformation and dynamic recrystallization (DRX) behaviors of the homogenized Mg-5.6Gd-0.8Zn (wt.%) alloy with high density lamellar long period stacking ordered (LPSO) phases were investigated. The hot compression tests were conducted at temperatures (T) ranging from 350 °C to 500 °C and strain rates (ε ˙) ranging from 0.001 s to 1 to 1 s-1, by which the hot deformation behavior was characterized by true stress-strain curve and the constitutive equation was calculated. Except for the deformation conditions of T = 350 °C and ε ˙ = 0.1–1 s-1, the true stress-strain curves show DRX characteristics. The LPSO phases had inserted great influences on the deformation and DRX mechanisms of the alloy: (i) when deformed at T = 350–450 °C, the LPSO phases had good thermal stability while both twinning and kinking played an important role under various strain rates. The degree of DRX was low and DRXed grains were small. (ii) When deformed at T = 500 °C, the LPSO phases were almost melted into the matrix and slip played a dominant role while the degree of DRX was high and its grains were significantly grown. • Homogenized Mg-5.6Gd-0.8Zn (wt.%) alloy contains high density lamellar LPSO phase. • Twinning and kinking play important roles during hot deformation. • Large angle kink band boundary induces DRX. • LPSO phases hinder the occurrence of DRX. [ABSTRACT FROM AUTHOR]

Adiabatic shear deformation behaviors in cold-rolled copper under different impact loading directions were systemically investigated in this paper. Split Hopkinson Pressure Bar (SHPB) system was used for the dynamic test. The microstructure and microtexture of the received shear localization regions were investigated by optical microscopy (OM), electron backscatter diffraction (EBSD) technique and microhardness tests. Three hat-shaped specimens were cut from cold-rolled copper sheet with the direction with an angle of 0° (RD sample), 45° (RD-45° sample) and 90° (TD sample) from the rolling direction within the rolling plane. The stress-strain curves indicate that the mechanical properties of the cold-rolled copper sheet show regularity in the work hardening dominated stage and that the shear stress of TD sample is the highest in that of the those three. OM results show that the morphology of adiabatic shear band in three samples shows differences that their deformation processes fall into two categories, pure relative shearing in RD sample and relative shearing with rotation in RD-45° and TD sample. EBSD results reveal that ultrafine grains with high-angle-boundaries are found within the adiabatic shear bands in three samples. The microhardness measurements show that the microhardness of shear region in three samples are significant higher than that of other regions. However, the size of grains within the shear band in RD sample are much larger than that in the other two samples. Microtexture analysis reveals that the grain orientations inside the shear band in three samples show similar characteristics that the <110> direction tends to parallel to the local shear direction and the {111} and {100} planes tend to parallel to the local shear plane. The calculated results show that rotational dynamic recrystallization can take place in the shear band. [ABSTRACT FROM AUTHOR]

We note that intussusception was likely associated with severe acute respiratory syndrome coronavirus-2 infection in 2 infants in Wuhan and London. The intussusception was reduced by enemas in Wuhan; the outcome was fatal. The intussusception was not reduced by enemas in London and required surgery; the outcome was favorable. [ABSTRACT FROM AUTHOR]

We report the clinical history, laboratory findings, and imaging features of coronavirus disease 2019 (COVID-19) in a neonate whose mother was also a patient. The newborn was the youngest patient with COVID-19 in the world at the time he was diagnosed. This case has brought more attention and understanding to the epidemic and mode of transmission of the disease. [ABSTRACT FROM AUTHOR]

We aimed to analyze the microstructure changes of knee cartilage in Juvenile idiopathic arthritis (JIA) patients with active synovitis using quantitative magnetic resonance imaging (MRI) T2 mapping technique. This study included 23 JIA patients, who underwent bilateral knee joints by using a MR imaging protocol with the addition of a coronal T2 mapping. The femorotibial joint cartilage of participants was divided into eight subregions. Twenty-four (52.17%) of 46 joints (non-synovitis group), and twenty-two (47.83%) joint cases (active-synovitis group) were respectively calculated the T2 mean values for each subregion. Student's T test or Mann–Whitney U test was used to determine the statistical differences of each subregion in the non-synovitis and active-synovitis groups, which is also applied to define the distribution differences of cartilage subregion in femoral and tibial. The T2 mean values of the superficial and deep zone of cartilage for active synovitis group were respectively higher than those for non-synovitis group (P < 0.05), except for the deep zone of cartilage in lateral tibial plateau (LTP) (P > 0.05). The mean T2 values of the deep zone in femoral cartilage for active synovitis group were significantly higher than that of tibial (P < 0.05). The finding of an increased average T2 values in active synovitis for JIA patients, especially in the deep cartilage of femoral condyle, which suggests that T2 values may reflect cartilage microstructure differences that occur in JIA. T2 mapping as an objective and quantitative method may allow for early detection of cartilage changes. [ABSTRACT FROM AUTHOR]

The mechanical behavior and microstructure characteristics of Ti-5Mo-5V-8Cr-3Al alloy were investigated with hat-shaped samples compressed under quasi-static and dynamic loading. Compared with the quasi-static loading, a higher shear stress peak and a shear instability stage were observed during the dynamic shear response. The results showed that an adiabatic shear band consisting of ultrafine equiaxed grains was only developed in the dynamic specimen, while a wider shear region was formed in the quasi-static specimen. The microhardness measurements revealed that shear region in the quasi-static specimen and adiabatic shear band in the dynamic specimen exhibited higher hardness than that of adjacent regions due to the strain hardening and grain refining, respectively. A stable orientation, in which the crystallographic {110} planes and <111> directions were respectively parallel to the shear plane and shear direction, developed in both specimens. And the microtexture of the adiabatic shear band was more well-defined than that of the shear region in the quasi-static specimen. Rotational dynamic recrystallization mechanism was suggested to explain the formation of ultrafine equiaxed grains within the adiabatic shear band by thermodynamic and kinetic calculations. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of Mg 97 Y 2 Zn 1 alloys during rolling at 450 °C and 500 °C have been investigated in this work. The microstructure of pre-rolled alloy mainly consisted of the α-Mg matrix, block 18R LPSO phase distributed at the grain boundary, and lamellar 14H LPSO phase distributed in grain interior. After rolling, the 18R LPSO phase and 14H LPSO phase were kinks obviously at both temperatures of alloys. The alloy rolled at 500 °C produced serious DRX, and the occurrence of DRX is related to the 14H LPSO phase: (i) the interface between 14H LPSO phase and α-Mg matrix could act as a nuclear site of DRX grain and further refine grain by discontinuous DRX mechanism. (ii) The kink boundary of 14H LPSO phase evolved into a grain boundary through the continuous DRX mechanism and promotes the generation of DRX. Tensile testing indicated that the alloy rolled at 450 °C possessed the higher yield strength, and the alloy rolled at 500 °C had the higher ultimate tensile strength. The dominant deformation mechanism of the 450 °C rolled alloy was a prismatic slip and prismatic kink, and the formation of a strong rolling basal texture resulted in the improvement of yield strength. For the alloy rolled at 500 °C, the formation of rolling texture is mainly related to twinning. In addition, the severe DRX degree with refined DRX grains contributed to the improvement of ultimate strength and ductility for the alloy rolled at 500 °C. [ABSTRACT FROM AUTHOR]

Microstructure and mechanical properties of the Mg-6.75%Zn-0.57%Zr-0.4%Y-0.18%Gd sheets processed by unidirectional and cross rolling were investigated. Compared with the unidirectional rolling (UR) sheet, cross rolling (CR) sheet exhibits finer grain size, weaker basal texture, higher recrystallized volume fraction and higher strength. Meanwhile, the UR sheet shows strong mechanical anisotropy, while the approximate mechanical isotropy is successfully achieved in the CR sheet. Cross rolling effectively reduced the anisotropy of mechanical properties. The finer grains in the CR sheet are responsible to its higher yield strength. The anisotropy of yield strength results from the basal slip, while the activation of prismatic slip reduced this anisotropy. The recrystallized components in the CR sheet weaken basal texture, thereby reducing anisotropy. [ABSTRACT FROM AUTHOR]

There is evidence to show that downregulation of miR-1 expression is closely related to cancer progression, including in nasopharyngeal carcinoma ( NPC). However, the molecular mechanisms underlying miR-1 downregulation in NPC remain largely unknown, especially its association with Epstein-Barr virus ( EBV). In this study we found that restoration of miR-1 dramatically inhibited cell invasion in vitro, together with tumour growth and metastasis in vivo. Importantly, we found that LMP1, an Epstein-Barr virus ( EBV)-associated protein, suppressed miR-1 expression. Furthermore, we identified K-ras as a novel direct target of miR-1. Our results demonstrated for the first time that miR-1 was suppressed by LMP1 and its tumour-suppressive effects were mediated chiefly by repressing K-ras expression. We propose that miR-1 could serve as an independent biomarker to identify patients with different clinical characteristics. [ABSTRACT FROM AUTHOR]

Precipitate strengthening against {10 1 ¯ 2} twinning was examined and compared with basal and prismatic slip in a strongly textured Mg 9Al extrusion plate. The plate was aged for various periods of time and mechanically tested in three orientations. The estimated critical resolved shear stresses (CRSS) for {10 1 ¯ 2} twinning was increased by 54 MPa, significantly larger than the 18 MPa for basal and the 21 MPa for prismatic slip. Of the two types of precipitate responsible for the larger increment of CRSS for twinning, the discontinuous precipitate was suggested to have a stronger suppressing effect on the twin nucleation and propagation than the continuous precipitate. • Discontinuous precipitate is dominant type of precipitate in this study. • Precipitate strengthening against {10 1 ¯ 2} twinning is much higher than that against slip. • Twinning appears far less in matrix occupied by discontinuous precipitate. • Continuous precipitate is suggested to increase the stress for twin growth. • Discontinuous precipitate is suggested to suppress twin nucleation and propagation. [ABSTRACT FROM AUTHOR]

Purpose: To characterise the pattern of change of diffusional kurtosis imaging (DKI) parameters (including kurtosis and diffusion parameters) in both white matter and gray matter in normal brain development with a large sample of subjects from term-born neonates to 14-years old children.Methods: Two hundred and eighteen normal children (136 male, 82 female) underwent conventional magnetic resonance imaging and DKI. Regions of interest (ROIs) were placed in 7 white matter areas and 4 gray matter areas. Then the DKI-derived parameters were automatically calculated, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (Da), radial diffusivity (Dr), mean kurtosis (MK), axial kurtosis (Ka) and radial kurtosis (Kr). The correlation between the DKI parameters and ages were analyzed using nonlinear fit, and the rate of parameter change was computed compared to the baseline value of the neonates.Results: For all ROIs in the white matter and gray matter, the FA, MK, Kr, Ka values increased with age, while the MD and Dr values decreased with age. The correlations were good to excellent, which changed rapidly within the first 2 years and relatively slowly after 2 years. The Da values in peripheral white matters and some gray matter structures (caudate nucleus and putamen) decreased with age. The amplitude of kurtosis parameters variation was greater than that of the diffusion parameters in both white matter and gray matter.Conclusions: The DKI parameters correlated well with age, and kurtosis parameters showed a potential advantage in detecting the normal brain development of children. [ABSTRACT FROM AUTHOR]

Purpose: On MR imaging, peritumoral T2 hyperintensity surrounding glioblastoma is known to contain tumor cell infiltrates, thus contributing to poor prognosis. This study aimed to determine the incremental prognostic value of radiomics on peritumoral T2 hyperintensity in pretreatment glioblastoma.Methods: One hundred fourteen pathologically confirmed glioblastoma patients were retrospectively selected from March 2008 to May 2018 (our institution, n = 61; the Cancer Imaging Archive, n = 53). All patients were randomly divided into either training (n = 80) or test set (n = 34). Manually segmented peritumoral T2 hyperintensity yielded 106 radiomic features per patient. A random forest variable selection was used to select the most relevant radiomic features. Four Cox proportional hazards models were fitted with clinical features, clinical features with tumor/peritumoral volumes, radiomics, and all of them combined. Kaplan-Meier survival curves of the models were plotted with log-rank tests. All models were validated on a test set using prediction error curves over survival times.Results: A random forest variable selection yielded five relevant features among the 106 radiomic features (two shape, two gray-level and one first order features). These radiomic features increased survival prediction accuracy when they were added onto clinical and tumor/peritumoral volumetric features (combined model, P = 0.011). On test set, the combined model showed lower mean survival prediction error rate (0.14) than clinical (0.191) or radiomic (0.178) model.Conclusions: The clinical model with radiomic features demonstrated improved survival predictive performance than the model without radiomic features, thus suggesting incremental prognostic value of peritumoral radiomics as MR imaging biomarker in pretreatment glioblastoma. [ABSTRACT FROM AUTHOR]