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Background Long non-coding RNAs (lncRNAs) are essential indicators for hepatocellular carcinoma. LncRNAs can exert the same functions as their antisense mRNAs. ILF3 is an oncogene in hepatocellular carcinoma. ILF3 divergent transcript (ILF3-AS1) is the antisense RNA of ILF3, and has been reported as an oncogene in various cancers. Aims To explore the role of lncRNA ILF3-AS1 in malignant phenotypes of hepatocellular carcinoma cells. Methods and results RT-qPCR analysis revealed that ILF3-AS1 was significantly upregulated in hepatocellular carcinoma cells. The hepatocellular carcinoma cell viability was suppressed by silenced ILF3-AS1. Transwell and wound healing assays showed that ILF3-AS1 downregulation inhibited cell invasion and migration. The levels of proteins associated with epithelial-mesenchymal transition (EMT) process and the Notch pathway were detected by western blot analysis. Luciferase reporter, RNA pull down and RIP assays were used to investigate the relationship between ILF3-AS1 and downstream target genes. ILF3-AS1 competed with meis homeobox 2 (MEIS2) for miR-628–5p in hepatocellular carcinoma cells. ILF3-AS1 elevated the levels of key proteins on the Notch pathway. Rescue assays demonstrated that MEIS2 reversed the antitumor effects of silenced ILF3-AS1 on hepatocellular carcinoma. In vivo assays demonstrated that ILF3-AS1 silencing inhibited the hepatocellular carcinoma tumor growth. Conclusions ILF3-AS1 promoted hepatocellular carcinoma progression via the Notch pathway and miR-628–5p/MEIS2 axis.

Kidney tumors are the second most frequent urology tumors. They are of many types, mostly existing as malignant tumors. In order to improve the accuracy of segmentation and classification of kidney...

An accurate and computationally efficient SLAM algorithm is vital for autonomous vehicles. Most modern SLAM systems use feature detection approaches to limit computational requirements. Feature detection through a 3D point cloud can be a computationally challenging task. In this paper, we propose a feature-based SLAM algorithm using 2D image projections of the 3D laser point cloud. We use a camera parameters matrix to rasterize the 3D point cloud to an image. Then ORB feature detector is applied to these images. The proposed method gives repeatable and stable features in a variety of environments. Based on such features, we can estimate the 6dof pose of the robot. For loop detection, we employ a 2-step approach, i.e., nearest key-frame detection and loop candidate verification by matching features extracted from rasterized LIDAR images. We evaluate the proposed system with implementation on the KITTI dataset. Through experimental results, we show that the algorithm presented in this paper can substantially reduce the computational cost of feature detection from the point cloud and the whole SLAM system while giving accurate results.

Most real-time autonomous robot applications require a robot to traverse through a dynamic space for a long time. In some cases, a robot needs to work in the same environment. Such applications give rise to the problem of a life-long SLAM system. Life-long SLAM presents two main challenges i.e. the tracking should not fail in a dynamic environment and the need for a robust and efficient mapping strategy. The system should update maps with new information; while also keeping track of older observations. But, mapping for a long time can require higher computational requirements. In this paper, we propose a solution to the problem of life-long SLAM. We represent the global map as a set of rasterized images of local maps along with a map management system responsible for updating local maps and keeping track of older values. We also present an efficient approach of using the bag of visual words method for loop closure detection and relocalization. We evaluate the performance of our system on the KITTI dataset and an indoor dataset. Our loop closure system reported recall and precision of above 90 percent. The computational cost of our system is much lower as compared to state-of-the-art methods. Our method reports lower computational requirements even for long-term operation.

Background The outbreak of COVID-19 has led to increased workload and infection risks among medical staff. This situation may influence current medical and health-related students’ decision on the choices of their future careers. Hence, this study investigated the impact of COVID-19 on their future career intentions. Methods This is a cross-sectional observational study that included medical and health-related students from three universities between October 2020 and January 2021. The study questionnaire was divided into two main sections: Section 1, which comprised students’ basic information. And section 2 focused mainly on the impact of COVID-19 pandemic on students’ professional intentions. The chi-squared χ2 test was used to compare the responses before and after the pandemic outbreak among Chinese and non-Chinese students. Results In overall, 1253 students completed the questionnaires. The responses showed that the number of students who preferred clinical medicine, public health, pharmacy and oral medicine increased significantly after the pandemic outbreak. In contrast, the number of students who chose nursing and medical technology decreased significantly. The change mainly occurred in Chinese students, predominantly females. Half of students (50.35%) were more willing to engage in medical and health work after completing their current program. Also, 36.39% of students felt that knowledge was too limited in the pandemic’s face and would like to continue studying after graduation to gain more knowledge. Due to the pandemic, 34.18% of students would like a future workplace near their hometown, and 19.63% preferred to work in urban areas. Conclusion The COVID-19 outbreak impacted current medical and health-related students’ career planning on their future workplaces and employment time choices. Additionally, the pandemic influenced the intention of Chinese students in choosing their future careers. This study provided the basis for the policymaking, specialty setting of colleges and supplied the medical health department’s talent reserve information.

Free-range chickens might mediate the spread of Cryptosporidium oocysts to humans and other animals. Few studies have evaluated the prevalence of Cryptosporidium species in domestic free-range poultry in China. Here, we characterized the prevalence and distribution of species and genotypes of Cryptosporidium in domestic free-range chickens, ducks, and geese in Anhui Province, China. A total of 1910 fresh fecal samples from three poultry species were examined from 18 free-range poultry farms by nested PCR and analysis of the Cryptosporidium SSU rRNA gene. The overall prevalence of Cryptosporidium species was 2.9% (55/1910), with infection rates of 1.3% (11/829) in chickens, 7.3% (36/487) in ducks, and 1.4% (8/594) in geese. C. baileyi (0.6%), C. meleagridis (0.2%), C. galli (0.2%), and C. xiaoi-like genotype (0.2%) were identified in chickens, and only C. baileyi was identified in ducks and geese, with infection rates of 7.4% and 1.3%, respectively. C. baileyi was the most prevalent species. Sequencing of the GP60 gene revealed that the C. meleagridis isolates belonged to the IIIbA26G1R1b subtype. This is the first study to document C. galli and C. xiaoi-like genotype in domestic free-range chickens in China. These findings expand the range of avian hosts known for Cryptosporidium and highlight the need for additional studies to characterize the diversity of Cryptosporidium in avian species.

This paper presents a novel robotic navigation system integrating a visual simultaneous localization and mapping (V-SLAM) based global planner with a deep reinforcement learning (DRL) based local p...

The Genome Warehouse (GWH) is a public repository housing genome assembly data for a wide range of species and delivering a series of web services for genome data submission, storage, release, and sharing. As one of the core resources in the National Genomics Data Center (NGDC), part of the China National Center for Bioinformation (CNCB, https://ngdc.cncb.ac.cn), GWH accepts both full genome and partial genome (chloroplast, mitochondrion, and plasmid) sequences with different assembly levels, as well as an update of existing genome assemblies. For each assembly, GWH collects detailed genome-related metadata of biological project, biological sample, and genome assembly, in addition to genome sequence and annotation. To archive high-quality genome sequences and annotations, GWH is equipped with a uniform and standardized procedure for quality control. Besides basic browse and search functionalities, all released genome sequences and annotations can be visualized with JBrowse. By May 21, 2021, GWH has received 19,124 direct submissions covering a diversity of 1108 species and has released 8772 of them. Collectively, GWH serves as an important resource for genome-scale data management and provides free and publicly accessible data to support research activities throughout the world. GWH is publicly accessible at https://ngdc.cncb.ac.cn/gwh.

Purpose Innovation has been acknowledged as the key for modern industries. However, the construction industry is criticised for being poor in innovation performance compared to other industry sectors. Large construction firms are the main contributor to technological innovation in the construction industry, but the driving process of their technological innovation has not yet been fully investigated in previous studies. The purpose of this paper is to provide quantitative analysis of the technological innovation driving process of large construction firms. Design/methodology/approach An extended crépon, duguet and mairesse (CDM) model has been developed to analyse the key influencing factors for technological innovation in construction firms. The sample data are selected from the world’s largest construction market, China, and include 129 listed construction firms. Findings The results show significant positive correlation between R&D investment and innovation output and also between innovation output and performance. The effect of influencing factors on the R&D investment, innovation output and performance are also revealed by the empirical study. The underlying reasons are discussed and suggestions are given for the construction industry to improve the technological innovation capacity of construction firms. Originality/value This research contributes to the literature of construction innovation and benefits practitioners by providing a quantitative approach to demonstrate the driving process of innovation in construction firms.

This paper presents a method for the optimisation of wheel–rail profiles, and this is based on the relationships between the equivalent conicity, RRD curve and rail profile slope. This method can b...

BACKGROUND: The aim of the present study was to assess the feasibility of applying low-dose contrast media (CM), and to explore the optimal virtual monoenergetic images (VMIs) in run-off computed tomography (CT) angiography (CTA) on dual-layer spectral detector CT (SDCT). METHODS: Forty patients were randomly assigned into a control group using routine volume CM (group A) and an experimental group using half-volume CM (group B). In groups A and B, 120 kVp polychromatic conventional images were generated via hybrid iterative reconstruction algorithm defined as A1 and B1, respectively. Additionally, in group B, VMIs (range, 40–120 keV) were reconstructed via a spectral reconstruction algorithm defined as B2–B10. Vascular attenuation, noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and radiation dose were evaluated. Subjective evaluation was performed using a 5-point scale. RESULTS: The patient demographics and radiation dose demonstrated no significant difference between groups A and B [dose length product (DLP): 1,823.45±512.68 vs. 2,014.40±453.25 mGy·cm, P=0.229; volume CT dose index: 14.92±3.40 vs. 16.26±2.85 mGy, P=0.208; the effective dose (ED): 10.82±3.02 vs. 11.88±2.67 mSv, P=0.229]. The mean vascular attenuation was higher in group B2 (40 keV) and was lower in group B3 (50 keV) in comparison with that in group A1 (487.07±154.21 vs. 414.35±71.66 HU, 329.90±100.25 vs. 414.35±71.66 HU, P>0.05). Compared with group A1, the mean noise was similar in group B2 (40 keV) and was lower in group B1 and groups B3–B10 (50–120 keV) (14.81±5.67 vs. 17.29±4.70 HU, P>0.05; 6.75±1.23–11.26±3.24 vs. 17.29±4.70 HU, P0.05). Scores of subjective image quality (IQ) in group B2 (40 keV) and B3 (50 keV) were similar to those in group A1 {5 [4.25, 5] vs. 5 [4, 5], 5 [5, 5] vs. 5 [4, 5], P>0.05}, and showed a declining trend in group B4 (60 keV) {4 [4, 5] vs. 5 [4, 5], P>0.05}. CONCLUSIONS: It is feasible to perform run-off CTA using low-dose CM with VMI on SDCT. The VMIs at 40–50 keV were the optimal choice and did not compromise IQ.

Pyrrolizidine alkaloids (PAs) are a type of natural phytotoxin that contaminate food and feed and become an environmental health risk to humans and livestock. PAs exert toxicity that requires metabolic activation by cytochrome P450 (CYP) 3A, and case reports showed that fetuses are quite susceptible to PAs toxicity. The aim of this study was to explore the characteristics of developmental toxicity and fetal hepatotoxicity induced by retrorsine (RTS, a typcial toxic PA) and the underlying mechanism. Pregnant Wistar rats were intragastrically administered with 20 mg/(kg·day) RTS from gestation day (GD) 9 to 20. Results showed that prenatal RTS exposure lowered fetal bodyweights, reduced hepatocyte numbers, and potentiated hepatic apoptosis in fetuses, particularly females. Simutaneously, RTS increased CYP3A expression and pregnane X receptor (PXR) activation in female fetal liver. We further confirmed that RTS was a PXR agonist in LO2 and HepG2 cell lines. Furthermore, agonism or antagonism of androgen receptor (AR) either induced or blocked RTS-mediated PXR activation, respectively. As a PXR agonist, RTS toxicity was exacerbated in female fetus due to the increased CYP3A induction and self-metabolism, while the inhibitory effect of AR on PXR activation reduced the susceptibility of male fetus to RTS. Our findings indicated that PXR may be a potential therapeutic target for PA toxicity.

Presented in this paper is a novel method for the mapping and semantic modeling of an underground parking lot using 3D point clouds collected by a low-cost Backpack Laser Scanning (BLS) or LiDAR system. Our method consists of two parts: a Simultaneous Localization and Mapping (SLAM) algorithm based on Sparse Point Clouds (SPC) and a semantic modeling algorithm based on a modified PointNet model. The main contributions of this paper are as follows: (1) a probability frontend framework for the alignment of point clouds using the local point cloud surface variance as the weight of registration, which modifies registration failure caused by the lack of features in sparse point clouds, (2) a robust submap-based strategy for loop closure detection and back-end optimization under sparse point clouds, and (3) a modified PointNet model for classifying the point clouds of underground parking lots into four categories: ceiling, floor, wall, others. Experimental results show that our SPC-SLAM algorithm achieves centimeter-level accuracy (0.09% trajectory error rate) after closed loop processing in a Global Navigation Satellite System (GNSS)-denied underground parking lot, and precision of 84.8% in semantic segmentation.

Low cost and high performance are the pursuing goals of the light-emitting diode (LED) packaging. The phosphor layer configuration of LEDs significantly influences optical performances. In this study, thermalcapillary flow was introduced in the phosphor coating by the blue laser local irradiation. It has been demonstrated to successfully manipulate the phosphor particle distributions. In the phosphor dispensing coating, a centripetally concentrated particle distribution was realized and resulted in high angular color uniformity (ACU) and low-cost manufacture. Its angular correlated color temperature (CCT) deviation was reduced by more than 65%, compared to the traditional phosphor dispensing coating. Besides, the phosphor amount is saved by about 12%. The mechanism of ACU enhancement is analyzed. The realized phosphor particle distribution can inspire further development of the optimized phosphor layer configuration.

Gastric cancer (GC) is a common digestive malignancy with a high-ranking morbidity and mortality. Therefore, it is urgent to identify novel indicators and develop new strategies for clinical diagnosis and treatment of GC. As a type of noncoding RNA, circular RNAs (circRNAs) have received increased attention in GC during recent years. To more comprehensively understand current research progress on circRNAs in GC, in this review, we introduce basic knowledge of circRNAs, summarize abnormally expressed circRNAs and discuss their functions and regulatory molecular mechanisms in GC. Then, we review potential applications of circRNAs for GC diagnosis, prognosis and treatment. Finally, we conclude by highlighting major advancements of circRNAs in GC research, and we discuss existing challenges and possible future research directions of GC-associated circRNAs.

Inorganic metal halide perovskite quantum dots (QDs) have emerged as a new class of solution-processable semiconductor materials for next-generation displays. However, such QDs commonly suffer from surface defects, resulting in low photoluminescence quantum yields (PLQYs) and inefficient charge carrier transport in perovskite QD based light-emitting diodes (perovskite QD-based LEDs). Herein, we propose an effective strategy of introducing gallium (Ga) cations to passivate surface defects in the CsPbBr3 QDs for the fabrication of bright perovskite QD-based LEDs. Partial Ga cations in the CsPbBr3 QD surfaces are beneficial for their surface defect passivation and their crystalline quality. Correspondingly, the radiative recombination and carrier mobility are greatly enhanced compared with the pristine ones. The PLQY of CsPbBr3 QDs passivated with 40% Ga cations is increased from 60.2% to 86.7%. The corresponding perovskite QD-based LEDs exhibit a maximum brightness of 11 777 cd m−2, more than two times higher than that of the pristine QD-derived device. The corresponding operational stability is also greatly enhanced relative to the pristine-derived device. The proposed Ga cation passivation strategy paves the way toward the fabrication of highly efficient perovskite QD-based LEDs for applications such as perovskite QD-based LED displays and light conversion based micro-LED displays.

Introduction The Kleihauer-Betke (KB) test is the diagnostic standard for the quantification of fetomaternal hemorrhage (FMH). Manual analysis of KB slides suffers from inter-observer and inter-laboratory variability and low efficiency. Flow cytometry provides accurate quantification of FMH with high efficiency but is not available in all hospitals or at all times. We have developed an automated KB counting system that uses machine learning to identify and distinguish fetal and maternal red blood cells (RBCs). In this study, we aimed to evaluate and compare the accuracy, precision, and efficiency of the automated KB counting system with manual KB counting and flow cytometry. Methods The ratio of fetal RBCs of the same blood sample was quantified by manual KB counting, automated KB counting, and flow cytometry, respectively. Forty patients were enrolled in this comparison study. Results Comparing the automated KB counting system with flow cytometry, the mean bias in measuring the ratio of fetal RBCs was 0.0048%, with limits of agreement ranging from -0.22% to 0.23%. Using flow cytometry results as a benchmark, results of automated KB counting were more accurate than those from manual counting, with a lower mean bias and narrower limits of agreement. The precision of automated KB counting was higher than that of manual KB counting (intraclass correlation coefficient 0.996 vs 0.79). The efficiency of automated KB counting was 200 times that of manual counting by the certified technologists. Conclusion Automated KB counting provides accurate and precise FMH quantification results with high efficiency.

Acquisition of a lipid-laden phenotype by immune cells has been defined in infectious diseases and atherosclerosis but remains largely uncharacterized in cancer. Here, in breast cancer models, we found that neutrophils are induced to accumulate neutral lipids upon interaction with resident mesenchymal cells in the premetastatic lung. Lung mesenchymal cells elicit this process through repressing the adipose triglyceride lipase (ATGL) activity in neutrophils in prostaglandin E2-dependent and -independent manners. In vivo, neutrophil-specific deletion of genes encoding ATGL or ATGL inhibitory factors altered neutrophil lipid profiles and breast tumor lung metastasis in mice. Mechanistically, lipids stored in lung neutrophils are transported to metastatic tumor cells through a macropinocytosis-lysosome pathway, endowing tumor cells with augmented survival and proliferative capacities. Pharmacological inhibition of macropinocytosis significantly reduced metastatic colonization by breast tumor cells in vivo. Collectively, our work reveals that neutrophils serve as an energy reservoir to fuel breast cancer lung metastasis.

We investigate the effects of the signal walk-in timing measurements and the methods to compensate for the error when leading-edge discriminator (LED) triggering was used. Three pairs of crystals (LaBr3 cubes, lutetium-yttrium oxyorthosilicate (LYSO) cubes, and LYSO rectangular prisms) were tested for coincidence timing resolution (CTR) to evaluate four compensation methods: 1) Linear 1-D; 2) Logarithm 1-D; 3) Polynomial 2-D; and 4) artificial neural network (ANN) 2-D. The experimental results show that: 1) the signal walk causes a logarithmic relationship between energy and measured time; 2) the signal walk dramatically affects the timing measurement at a wide energy window. The measured FWHM CTR decreased by 86.2%, from 670 ps to 92.7 ps, when the lower cut of the energy window was used; and 3) the Logarithm 1-D compensation can improve the timing performance. The FWHM CTRs decreased by 69.9% (from 326.8 ps to 101.3 ps) with an energy window of [300 keV–550 keV] and by 12.5% (from 97.2 ps to 85.1 ps) with an energy window of [410 keV–550 keV] for LaBr3 cube crystals. The results show that the Logarithm 1-D, Polynomial 2-D, and ANN 2-D compensations work well, achieving at least a 10% improvement in timing performance.

The effects of the white-light X-ray and 170-keV proton beam irradiation on the electrical and optical characteristics of the InGaN/GaN multiple quantum wells (MQWs) light-emitting diodes (LEDs) are analyzed and compared. Different from the negative effects of the proton irradiation, the X-ray irradiation shows positive effects on the LEDs’ performance. In detail, after the 100 Mrad(Si) X-ray irradiation, the p-n junction resistance decreases from the original 2.51 to $2.08~\Omega $ , the light output power increases from 170 to 203 mW (at a forward voltage of 3.2 V), and the maximal external quantum efficiency (EQE) increases from 56.7% to 61.8%. Based on the ABC model fittings, both the Shockley–Read–Hall recombination rate and the radiative recombination rate in the MQWs are improved by the X-ray irradiation. The Hall effect measurements reveal the chemical bond breaking of the Mg-H complex in the p-type GaN. Therefore, the improvement of the LED by the X-ray irradiation should be caused by the chemical bond variations of the defect-related complex in the MQWs and the Mg-H complex in the p-type GaN.

Influences of 170-keV protons beam irradiation on the static and dynamic properties of blue light InGaN/GaN multiple quantum wells (MQWs) microlight-emitting diodes (Micro-LEDs) were investigated. It was interesting to find out that, although threshold voltage and light output power of Micro-LEDs deteriorated after proton irradiation, a 3-dB bandwidth was greatly improved. In quantitative terms, at the forward current density of 1 kA/cm2, 3-dB bandwidth increased from original 7.34 to 119.74 MHz when Micro-LED exposed to proton beam with the fluence of $5\times 10^{14}$ p/cm2. Based on the frequency response data analysis, differential carrier lifetimes of Micro-LEDs, including Shockley–Read–Hall (SRH) lifetime and differential radiation recombination lifetime, were compared. The results pointed out that both SRH and recombination lifetimes became shorter after proton irradiation, indicating that competition between the nonradiative and radiative recombination processes was enhanced by proton beam. To reveal the origination of the 3-dB bandwidth improvement, photoluminescence (PL) and time-resolved PL (TRPL) spectrums of Micro-LEDs were measured. MQWs’ PL spectrum with a peak wavelength of 450 nm was observed and its intensity decreased as proton fluence increasing. Meanwhile, a PL peak at 550 nm, which was well known as defect-related PL spectrum, was enhanced by proton irradiation, especially at a proton fluence of $5\times 10^{13}$ and $5\times 10^{14}$ p/cm2, proving the increase of defects in epitaxial thin films as proton fluence increasing. In the TRPL experimental study, the nonradiative recombination lifetime decreased with proton fluence, which was consistent with the results analyzed by frequency response. Overall, the improvement of 3-dB bandwidth could be mainly attributed to the decrease of carrier lifetime in MQWs, which were caused by the generation of defects due to the atom displacement effect of proton irradiation.

With the aggravating trend of aging population in modern societies, Mobile Healthcare Social Network (MHSN) is an attracting platform for improving the life quality of elderly patients and offering mutual supports. In a sustainable MHSN system, one essential issue is to protect sensitive healthcare information while providing information-sharing for patients with multiple symptoms. To achieve multi-symptom matching and cross-domain communications for patients in MHSNs, we propose a new Secret Handshake scheme with Multi-Symptom intersection ( MSSH ), which is derived from a linear-complexity Authorized Private Set Intersection (APSI) based on Schnorr signature. In MSSH , two anonymous patients, who have registered with independent healthcare centers, are able to successfully execute an affiliation-hiding mutual anonymous authentication only if their target authentication policies are satisfied. The authentication policy demands that the designated healthcare center should be matched and the cardinality of their symptoms intersection is not less than a threshold value. Meanwhile, the symptoms outside of the set intersection remain confidential. The formal analysis proves MSSH is secure under the Random Oracle Model (ROM). The experimental results demonstrate that MSSH is efficient and feasible in MHSNs.

Background To compare the effects of perioperative dexmedetomidine with placebo (or other sedation) on the rate of postoperative delirium in adult patients who underwent non-cardiac surgeries. Methods A meta-analysis was performed on randomized, controlled trials. MEDLINE, the Cochrane Central Register of Controlled Trials, and Embase (to March 20, 2019) were searched for literature retrieval. The standardized primary outcome was postoperative delirium. We pooled risk ratios using a random-effects model. Results From 10 trials with 2,286 total participants, we recorded 363 postoperative delirium events during the follow-up periods. Compared with the control group, patients in the dexmedetomidine group had a postoperative delirium relative risk of 0.53 [95% confidence interval (CI), 0.37-0.76]. When the dexmedetomidine infusion rate was higher than 0.2 μg/kg/h, the relative risk of postoperative delirium reduced significantly by 34%, compared with other sedation methods (relative risk =0.66; 95% CI, 0.47-0.94; P=0.02), with no heterogeneity (I²=31%, P=0.18). While it reduced by 62% when the dexmedetomidine infusion rate was lower than 0.2 μg/kg/h (relative risk =0.38; 95% CI, 0.27-0.54). Conclusions Compared to the placebo (or other sedation methods), perioperative dexmedetomidine sedation resulted in lower rates of postoperative delirium in adult patients who underwent non-cardiac surgery.

With the increasingly close coupling between the cyber network and the physical power grid in Cyber Physical Power System (CPPS), the failure of cyber network has become an important cause of blackout. Equipment failure or abnormal operation state will be appeared without alarm in complex cyber network, which brings hidden failures not been diagnosed and dealt with in time. The invisibility and harmfulness of hidden failures pose a significant threat to the safe, reliable, and stable operation of CPPS. The dual hidden cascading failure model for CPPS is proposed to reveal the failure characteristics of CPPS accurately, considering not only the hidden faults in the power grid, but also the hidden failures in the cyber network. With the different coupled relationships between power systems and cyber networks, the cyber network topology with corresponding failure threshold is obtained according to the simulation of the model with different hidden failure rates of cyber network nodes. When the hidden failure rate is lower than the failure threshold, the scale-free topology cyber network coupled mode is adopted between power grids and cyber networks, otherwise the small-world topology cyber network coupled mode is adopted, which can effectively reduce the risk of power system blackouts. The method proposed in this paper is tested by using IEEE-118 power system and its cyber network. The results show that the method is effective.

Background: The COVID-19 pandemic presented severe challenges to emergency practice of acute coronary syndrome (ACS). However, poor evidence was shown on ACS in a non-hot-spot region. We sought to clarify the influence of the first-wave COVID-19 pandemic on emergency ACS from a non-epicenter region.Methods: This retrospective multicenter study was conducted in emergency ACS patients during the pandemic (from 2020-01-23 to 2020-03-29) and the ones during the same period in 2019. Clinical characteristics, timeline parameters and treatment strategies were compared between different groups. Association of the pandemic with non-invasive therapy was further assessed.Results: Compared with 2019, ACS had a drop in admission (267 cases vs. 475 cases) and invasive therapy (140 cases vs. 318 cases). Also, process delays were detected including the period from symptom onset to first medical contact (S-to-FMC, 5h vs. 2.5h), the period from FMC to electrocardiogram (ECG) completed (8min vs. 4min) and the period from FMC to dual antiplatelet therapy (FMC-to-DAPT, 25min vs. 19min). Primary percutaneous coronary intervention (PPCI) decreased by 54.9% in STEMI and early invasive therapy decreased by 59.2% in NSTE-ACS. The proportion of invasive therapy in NSTE-ACS decreased more than in STEMI (16.9% vs. 10.1%) with longer process delay. The pandemic was associated with increased non-PPCI in STEMI (OR=1.707, 95%CI 1.082-2.692, P=0.021) and elevated medication in NSTE-ACS (OR=2.029, 95%CI 1.268-3.247, P=0.003), respectively. Conclusion: Even in a non-epicenter region, the first-wave COVID-19 pandemic caused a significant reduction of invasive therapy and evident process delays in emergency ACS.

Clinical demographics have demonstrated that postmenopausal women are predisposed to chronic stress-induced cardiomyopathy (CSC) and this has been associated with the decrease of estrogen. Meanwhile, recent studies have implicated unsolved myocardial proinflammatory responses, which are characterized by enormous CD86+ macrophage infiltrations as an underlying disease mechanism expediting the pathological remodeling of the heart during chronic stress. However, we had previously demonstrated that estrogen confers cardioprotection via the modulation of cardiomyocytes β2-adrenoceptors (β2AR)-Gs/Gi pathways during stress to lessen the incidence of stress-induced cardiovascular diseases in premenopausal women. Intriguingly, macrophages express β2AR profoundly as well; as such, we sought to elucidate the possibilities of estrogen modulating β2AR-Gs/Gi pathway to confer cardioprotection during stress via immunomodulation. To do this, ovariectomy (OVX) and sham operations (Sham) were performed on female Sprague-Dawley (SD) rats. Two weeks after OVX, the rats were injected with 40 μg/kg/day of estradiol (E2). Next, on day 36 after OVX, chronic stress was induced by a daily subcutaneous injection of 5 mg/kg/day of isoproterenol (ISO). The effect of E2 on relevant clinical cardiac function indexes (LVSP, LVEDP, + dp/dt and −dp/dt), myocardial architecture (cardiomyocyte diameter and fibrosis), β2AR alterations, and macrophage (CD86+ and CD206+) infiltrations were assessed. In vitro, peritoneal macrophages (PMΦ) were isolated from wild-type and β2AR-knockout female mice. The PMΦ were treated with ISO, E2, and β2AR blocker ICI 118,551 for 24 h, and flow cytometric evaluations were done to assess their phenotypic expression. E2 deficiency permitted the induction of CSC, which was characterized by cardiac dysfunctions, maladaptive myocardial hypertrophy, unresolved proinflammatory responses, and fibrosis. Nonetheless, E2 presence/supplementation during stress averted all the aforementioned adverse effects of chronic stress while preventing excessive depletion of β2AR. Also, we demonstrated that E2 facilitates timely resolution of myocardial proinflammation to permit reparative functions by enhancing the polarization of CD86+ to CD206+ macrophages. However, this adaptive immunomodulation is hampered when β2AR is inhibited. Taken together, the outcomes of this study show that E2 confers cardioprotection to prevent CSC via adaptive immunomodulation of macrophage phenotypes, and β2AR-mediated signaling is crucial for the polarizations of CD86+ to CD206+ macrophages.

Frequency microcombs, alternative to mode-locked laser and fiber combs, enable miniature rulers of light for applications including precision metrology, molecular fingerprinting and exoplanet discoveries. To enable frequency ruling functions, microcombs must be stabilized by locking their carrier-envelope offset frequency. So far, the microcomb stabilization remains compounded by the elaborate optics external to the chip, thus evading its scaling benefit. To address this challenge, here we demonstrate a nanophotonic chip solution based on aluminum nitride thin films, which simultaneously offer optical Kerr nonlinearity for generating octave soliton combs and quadratic nonlinearity for enabling heterodyne detection of the offset frequency. The agile dispersion control of crystalline aluminum nitride photonics permits high-fidelity generation of solitons with features including 1.5-octave spectral span, dual dispersive waves, and sub-terahertz repetition rates down to 220 gigahertz. These attractive characteristics, aided by on-chip phase-matched aluminum nitride waveguides, allow the full determination of the offset frequency. Our proof-of-principle demonstration represents an important milestone towards fully integrated self-locked microcombs for portable optical atomic clocks and frequency synthesizers., Though octave soliton microcombs are attractive for on-chip metrology and optical clocks, limitations in existing materials lead to increased chip integration complexity. Here, the authors report access to octave soliton microcombs and self-referencing using aluminium nitride nanophotonic chips.

Realizing the rapid detection of ship targets is of great significance both in commercial shipping activities and in modern warfare. Compared with visible light remote sensing images, synthetic aperture radar (SAR) has good resolution characteristics for metal targets, making ship targets more clearly visible in high-resolution SAR images. However, there are often obvious coherent bright spots and sea clutter noise in high-resolution SAR images used for ship detection, which seriously affects the detection accuracy. This paper proposed a detection method that uses fast non-local means (FNLM) filter and deep learning methods. Using high-resolution SAR images as the data source, FNLM and deep learning methods are used to realize the detection of ships quickly and accurately. First, the FNLM filter was used to preprocess highresolution SAR images to reduce overall image noise while enhancing target definition and feature details; Then, the Faster R-CNN algorithm was used to conduct model training on large-scale SAR data sets, to extract detection features, to improve the convergence accuracy of the network, and to achieve automatic and rapid detection of ships on the sea. Experimental results showed that this method had good robust characteristics and target detection accuracy, and the average accuracy of ship target detection reaches more than 90%. In the case of severe sea clutter interference, it still had a better detection effect.

This paper proposes a new fuzzy-logic-inspired multi-contrast-agent strategy (MCAS) for optimal tumor classification. The proposed strategy accounts for the competitive and symbiotic relationships among multiple contrast agents through a sequential logic circuit analysis. Furthermore, the strategy enables an intuitive yet systematic way to analyze the tumor classification vagueness and ambiguous uncertainties and optimize the utilization of multiple agents through a fuzzy comprehensive evaluation. A numerical example is used to demonstrate how the classification performance in terms of decision-making fuzziness is significantly improved with an optimal “cocktail recipe” methodology using the proposed MCAS.

Lateral line of fish is an extraordinary mechanosensory organ, which plays a vital role in navigation, object detections, and energy-efficient swimming. The paper presents an artificial lateral line sensor (ALLS) for flow detection by using piezoelectric nanofiber based sensing cantilevers and implemented electronics. Interdigital electrodes were adopted to enable the P(VDF-TrFE)/BTO nanofiber membrane to operate in the thickness (d33) mode. SU-8 pillars, mimicking the cupula of fish lateral line, were fabricated by photolithography. Pre-amplifiers were implemented in the ALLS to reduce the complexity of external testing equipment. The ALLS achieved a velocity detection limit of 1.56 mm/s, which was greatly reduced compared to that of ALLS without preamplifiers.

Background Stent under-expansion is a main cause of acute coronary syndrome (ACS), which can lead to serious clinical outcomes. The rotational atherectomy of underexpanded coronary stents (academically called stent ablation, SA) by intravascular ultrasound (IVUS) may provide more visual reference in the intervention. We aim to analyze the procedural and long-term outcomes of the optimized strategy of SA in patients with ACS and to provide real-world data on this technique. Methods A total of 11 patients with ACS who underwent SA between April 2017 and January 2019 were analyzed. Clinical follow-ups were obtained either by telephone call or by scheduled visit. Clinical end-points included periprocedural and postprocedural myocardial infarction, stent thrombosis, target lesion revascularization, and major adverse cardiac events. Results The mean age of patients was 69.6±6.5 years, and five (45.5%) patients were males. All cases presented with unstable angina and were admitted with ACS. All patients required at least two burrs during the intervention and the size of the burr was selected based on the data of minimum lumen diameter (MLD), and the first and the second burr/stent MLD ratios were 0.93 (0.88-0.99) and 1.09 (1.02-1.14), respectively. Nine patients were treated with drug-eluting stents and two were treated with drug-coated balloons. There were no complications including no flow, perforation, or burr entrapment during the intervention. No in-hospital deaths or major adverse cardiac events were documented during the follow-up period. In our study, less contrast agent and a lower dose of radiation were used during the intervention. Conclusions SA guided by IVUS can reduce the risk of complications, assess the results of surgery, inform the selection of stent size, and decrease the required dose of radiation and contrast.

IDEA is a classic symmetric encryption algorithm proposed in 1991 and widely used in many applications. However, there is little research into white-box IDEA. In traditional white-box implementations of existing block ciphers, S-boxes are always converted into encoded lookup tables. However, the algebraic operations of IDEA without S-boxes, make the implementation not straight forward and challenging. We propose a white-box implementation of IDEA by applying a splitting symmetric encryption method, and verify its security against algebraic analysis and BGE-like attacks. Our white-box implementation requires an average of about 2800 ms to encrypt a 64-bit plaintext, about 60 times more than the original algorithm would take, which is acceptable for practical applications. Its storage requirements are only about 10 MB. To our knowledge, this is the first public white-box IDEA solution, and its design by splitting can be applied to similar algebraic encryption structures.

Background: The role of bronchial brushing Xpert MTB/RIF (hereafter referred to as Xpert) in patients with pulmonary tuberculosis (PTB) remains unclear. Therefore, a retrospective study was conducted aiming to evaluate the diagnostic efficiency of bronchial brushing Xpert in patients with PTB. Methods: Between July 2018 and August 2019, suspected PTB patients who were admitted to our hospital and had bronchial brushing and matched sputum collection for acid-fast bacilli (AFB) smear, mycobacterial culture, and Xpert were included for further analysis. Subsequently, PTB was defined based on mycobacterial culture, and if an alternative diagnosis was established, ‘non-tuberculosis (TB)’ was considered. Comparison of bronchial brushing and matched sputum examination was performed between groups. Then, the differences in the sensitivities between bronchial brushing and sputum Xpert were examined using the chi-square test. Results: A total of 111 patients were included and divided into TB and non-TB groups (52 versus 59 patients). The sensitivities of Xpert against culture were calculated as follows: sputum, 44.2% (23/52); bronchial brushing, 59.6% (31/52); sputum and bronchial brushing, 69.2% (36/52). The specificities of all Xpert assays were the same (100.0%, 59/59). A significant difference was found in the comparison of the sensitivities of Xpert using sputum, bronchial brushing and both, and the sensitivity of Xpert on both sputum and bronchial brushing was higher than that on sputum alone ( p Conclusion: Bronchial brushing Xpert improves the diagnostic efficiency of sputum Xpert in the detection of PTB.

Previously, serum miR-188-5p is differentially expressed in breast cancer, but the diagnostic potential of circulating miR-188-5p as well as its regulatory mechanism in breast cancer remain uncertain. Herein, serum miR-188-5p was detected by real-time polymerase chain reaction in patients with breast cancer, breast fibroadenoma, and healthy subjects. Circulating miR-188-5p was abnormally elevated in patients with breast cancer as compared with these other two groups, and was reduced in patients with breast cancer following surgical treatment. Increased serum miR-188-5p corresponded to lymph node metastasis status and TNM stages of breast cancer. A receiver operating characteristic curve analysis of the ability to circulate miR-188-5p to distinguish between patients with breast cancer and either noncancerous patients or patients with breast fibroadenoma yielded corresponding areas under the curve of 0.894 and 8.814. miR-188-5p was downregulated in the highly malignant cancer line MDA-MB-231 relative to the less malignant MCF-7 cells. In vitro, functional analyses conducted via transfecting cells with mimics and inhibitors revealed miR-188-5p to suppress breast cancer cell proliferation and migration, which was mediated by its downstream target IL6ST. Comparison of intracellular and exosomal miR-188-5p levels indicated that miR-188-5p was selectively sorted into exosomes derived from MDA-MB-231 cells rather than those from MCF-7 cells. However, exosomal miR-188-5p levels in the serum of patients with breast cancer were reduced compared to healthy controls and did not differ relative to patients with breast fibroadenoma. In summary, miR-188-5p acts in a tumor-suppressive manner in breast cancer progression and may serve as a noninvasive early diagnostic biomarker and therapeutic target in breast cancer.

Although the construction industry is an important economic pillar for a nation, and contributes greatly to the improvement of the citizens’ standards of living; it is criticized for intensive pollution and resource consumption during the operational process of construction projects. The stricter regulations of the government and the raising awareness of public on environmental protection bring more challenge and conflict to government funded construction projects for cleaner production. This research intends to investigate the conflicts the construction projects experienced in the changing social and political environment, and how the project teams resolve these conflicts. Through multiple case studies on six government funded projects, there are 17 types of conflict identified, linking to six groups of external stakeholders of the government funded projects. The causes and solutions of the conflicts are discussed with the help of site observation, document review and interview survey. Strategies and suggestions are provided for conflict management of government funded projects. The findings will benefit researchers and practitioners involved in construction industry by providing better perception and management of conflicts, therefore to promote cleaner production.

The high incidence aerodynamics of a lightweight jet trainer aircraft model has been investigated using a novel five degree-of-freedom (DoF) dynamic manoeuvre rig, recently updated with improved actuation and data acquisition systems, in the 7' x 5' closed-section low-speed wind tunnel at the University of Bristol. The major focus was to identify the nonlinear and unsteady aerodynamic characteristics specific to the stall region and which affect free-to-move aircraft model behaviour. First, the unstable equilibrium states in the limit cycle regions were stabilized, and so observed, over a wide range of angles of attack using a simple elevator feedback control law based on pitch angle and pitch-rate sensor measurements.Tests with two degrees-of-freedom, namely the aircraft model and rig arm pitch angles, revealed the existence of static hysteresis in the normal force acting on the aircraft model in the stall region. Unlocking the aircraft model in roll and yaw accompanied by feedback stabilization of the lateral-directional modes of motion demonstrated onset of asymmetric aerodynamic rolling and yawing moments in this four degree-of-freedom configuration. This observation implicitly indicates a link between the static hysteresis in the normal aerodynamic force with an onset of aerodynamic asymmetry. The experimental results show the efficiency of the updated multi-degree-of-freedom actively controlled manoeuvre rig in providing insight into complicated aerodynamic effects within the stall region.

This paper presents a direct visual odometry method with adaptive stereo coupling factor and relocalization. The adaptive stereo coupling factor is calculated by considering the number of co-visibility frames, which makes stereo direct odometry more robust. The map is built up with keyframes, connecting relationship of keyframes, poses of keyframes and descriptors. The map will be saved automatically when the proposed system shuts down, and will be loaded automatically when the proposed system starts up. Our proposed system always builds a new map until a loop closure is found between new map and loaded map. When loop closure in a loaded map is found, the proposed system will locate camera in the loaded map. Moreover, our proposed system detects loop closure with feature-based bag-of-words (BoW) method on a low resolution level, which makes the loop closure detection achieve realtime. Evaluation results on the KITTI dataset show that, with the aid of the adaptive stereo coupling factor, the stereo visual odometry becomes more accurate and robust. And evaluation results in real world show that the proposed system can successfully detect loop closure and relocate in realtime.

Background The COVID-19 pandemic posed a huge challenge to the education systems worldwide, forcing many countries to provisionally close educational institutions and deliver courses fully online. The aim of this study was to explore the quality of the online education in China for international medical and nursing students from low- and middle-income countries (LMICs) as well as the factors that influenced their satisfaction with online education during the COVID-19 pandemic. Methods Questionnaires were developed and administered to 316 international medical and nursing students and 120 teachers at a university in China. The Chi-square test was used to detect the influence of participants’ personal characteristics on their satisfaction with online education. The Kruskal–Wallis rank-sum test was employed to identify the negative and positive factors influencing the online education satisfaction. A binary logistic regression model was performed for multiple-factor analysis to determine the association of the different categories of influential factors—crisis-, learner-, instructor-, and course-related categories, with the online education satisfaction. Results Overall, 230 students (response rate 72.8%) and 95 teachers (response rate 79.2%) completed the survey. It was found that 36.5% of students and 61.1% of teachers were satisfied with the online education. Teachers’ professional title, students’ year of study, continent of origin and location of current residence significantly influenced the online education satisfaction. The most influential barrier for students was the severity of the COVID-19 situation and for teachers it was the sense of distance. The most influential facilitating factor for students was a well-accomplished course assignment and for teachers it was the successful administration of the online courses. Conclusions Several key factors have been identified that affected the attitudes of international health science students from LMICs and their teachers towards online education in China during the COVID-19 pandemic. To improve the online education outcome, medical schools are advised to promote the facilitating factors and cope with the barriers, by providing support for students and teaching faculties to deal with the anxiety caused by the pandemic, caring for the state of mind of in-China students away from home, maintaining the engagement of out-China students studying from afar and enhancing collaborations with overseas institutions to create practice opportunities at students’ local places.

Semantic mapping based on information of objects has become a crucial component for the surrounding comprehension and the more robust navigation. In this paper, we propose a system for simultaneous localization and mapping (SLAM) that combines multiple objects tracking and factor graph optimization with semantically meaningful landmarks to achieve accurate monocular semantic mapping. Firstly, the process of object recognition uses a vanishing point sampling-based approach to efficiently infer the class and position of object landmarks from 2D bounding box object detection. Secondly, The semantic frontend utilizes local matching-based data association to track raw cuboid proposals. It can provide semantic constraints to reduce cuboid scale drift and improve its position estimation. Finally, we present a multi-view factor graph optimization which can use motion modal of the camera to optimize stable cuboids. The semantic mapping experiments on our own built virtual scene show better accuracy and robustness over existing approaches. We evaluate the effectiveness of our approach on public KITTI datasets and a real scene.

The myodural bridge (MDB) connects the suboccipital musculature to the spinal dura mater (SDM) as it passed through the posterior atlanto-occipital and the atlanto-axial interspaces. Although the actual function of the MDB is not understood at this time, it has recently been proposed that head movement may assist in powering the movement of cerebrospinal fluid (CSF) via muscular tension transmitted to the SDM via the MDB. But there is little information about it. The present study utilized dogs as the experimental model to explore the MDB’s effects on the CSF pressure (CSFP) during stimulated contractions of the suboccipital muscles as well as during manipulated movements of the atlanto-occiptal and atlanto-axial joints. The morphology of MDB was investigated by gross anatomic dissection and by histological observation utilizing both light microscopy and scanning electron microscopy. Additionally biomechanical tensile strength tests were conducted. Functionally, the CSFP was analyzed during passive head movements and electrical stimulation of the suboccipital muscles, respectively. The MDB was observed passing through both the dorsal atlanto-occipital and the atlanto-axial interspaces of the canine and consisted of collagenous fibers. The tensile strength of the collagenous fibers passing through the dorsal atlanto-occipital and atlanto-axial interspaces were 0.16 ± 0.04 MPa and 0.82 ± 0.57 MPa, respectively. Passive head movement, including lateral flexion, rotation, as well as flexion–extension, all significantly increased CSFP. Furthermore, the CSFP was significantly raised from 12.41 ± 4.58 to 13.45 ± 5.16 mmHg when the obliques capitis inferior (OCI) muscles of the examined specimens were electrically stimulated. This stimulatory effect was completely eliminated by severing the myodural bridge attachments to the OCI muscle. Head movements appeared to be an important factor affecting CSF pressure, with the MDB of the suboccipital muscles playing a key role this process. The present study provides direct evidence to support the hypothesis that the MDB may be a previously unappreciated significant power source (pump) for CSF circulation.

This paper studies the feasibility of detecting the pneumonia due to the COVID-19 with microwave medical imaging. One challenge while formulating such a problem is to identify the disease in lungs whose dielectric permittivity is dynamically fluctuating with the respiration. In this paper, we utilize this feature by assuming that the permittivity of the disease has minor variation at microwave frequencies during the respiration, and thus the dielectric variance of the pixels at the diseased site over a number of consecutive images significantly differs from those of the other tissues in the thorax. Based on this assumption, we propose two approaches that make use of the a priori information (API) on the position of the heart and the symmetry of the thorax, respectively, to identify a diseased lung. Finally, these two approaches are numerically validated on a thorax phantom, and their performance is compared.

BackgroundGastric cancer (GC) is the fifth most common cancer worldwide. Previous studies have suggested that the tumor microenvironment (TME) plays an important role in the development and prognosis of GC. In this study, we aimed to identify genes in tumor-infiltrating immune cells (TICs) that influence the progression and prognosis of GC. MethodsWe used the ESTIMATE algorithm to calculate the scores of the stromal and immune components of the TME in 407 GC samples collected from The Cancer Genome Atlas (TCGA) database.The differentially expressed genes (DEGs) were intersected by a protein-protein interaction (PPI) network and analyzed by univariate Cox regression.Further analysis showed the correlation between MCEMP1 and the clinicopathological characteristics of GC patients (clinical stage, distant metastasis) and survival.Then we used Gene set enrichment analysis (GSEA) and CIBERSORT analysis to examine the relationship between MCEMP1 and the TME.ResultsThe analysis revealed that the expression of MCEMP1 was positively correlated with the clinicopathological characteristics of GC patients (clinical stage, distant metastasis) and negatively correlated with survival. Gene set enrichment analysis (GSEA) indicated that gene sets in the MCEMP1 high expression group were concentrated mainly in immune-related pathways. CIBERSORT analysis of the proportion of TICs revealed that neutrophils and M2 macrophages were positively correlated with MCEMP1 expression, suggesting that MCEMP1 is responsible for preservation of the immune-dominant status of the TME. ConclusionHigh MCEMP1 expression might be a biomarker of a poor prognosis in GC patients and provide a clue regarding the different statuses of the TME, offering additional insight into therapy for GC.

Surgical intervention use is common in the management of childhood pleural tuberculosis (TB), however, its associated risk factors remain unclear. Between January 2006 and December 2019, consecutive children patients (≤ 15 years old) who had a diagnosis of pleural TB were included for the analysis. Surgical intervention was defined as debridement (such as breaking loculations), decortication, and thoracic surgery (such as lobectomy or segmental resection). Patients undergoing surgery were included as surgical group, without surgery were classified as non-surgical group, surgical risk factors were then estimated. Univariate and multivariate logistic regression analysis were performed to evaluate the risk factors for surgical interventions. A total of 154 children diagnosed as pleural TB (definite, 123 cases; possible, 31 cases) were included in our study. Of them, 29 patients (18.8%) were classified as surgical group and 125 patients (81.2%) were classified as non-surgical group. Surgical treatments were analyzed in 29 (18.8%) patients, including debridement (n = 4), decortication (n = 21), and thoracic surgery (n = 4). Further multivariate analysis revealed that empyema (age- and sex-adjusted OR = 27.3, 95% CI 8.6, 87.1; P P

Background The concentration levels of major and trace elements are significantly correlated with human health. However, studies profiling major and trace elements among female using methamphetamine are rare. This study aims to investigate the major and trace elements changes and discover elemental biomarkers in plasma of female methamphetamine (METH) addicts in six months’ compulsory treatment. Methods A total of 60 female METH addicts selected from drug rehabilitation center were randomly divided into three equal groups: (1) Detoxification for one month; (2) Detoxification for three months; (3) Detoxification for six months. Twenty healthy women, without drug abuse history were selected as control group. Four major elements including Na, Mg, K, Ca and twelve trace elements including V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, Sn, Pb were determined using inductively coupled plasma mass spectrometry (ICP-MS). The results were analyzed using One-way Analysis of Variance (ANOVA) and Student-Newman-Keuls (SNK test). Elemental biomarkers were discovered based on orthogonal partial least squares discriminant analysis (OPLS-DA). Results The four groups used in the study were divided into four significant sections according to scatter plots. The total elemental concentrations of three METH withdrawal groups were increased compared to the control group. Over six months, element contents of the withdrawal groups gradually equaled element contents of the control group in compulsory treatment. The variable importance in the projection values (VIP > 1) of OPLS-DA model and SNK test (p Conclusion Major and trace elements demonstrated significant differences between control group and three METH withdrawal groups. Fe, Cu, Cr and Se are potential elemental biomarkers among METH-abused female groups. Metabolic disorders of major and trace elements exist in the female methamphetamine addicts.

We demonstrate an efficient optical parametric oscillator at the telecom band using a triple-resonant, periodically poled lithium niobate microring resonator, which, to the best of our knowledge, delivers the lowest threshold power (∼30 µW) for on-chip OPOs so far.

Materials with strong second-order ( χ ( 2 ) ) optical nonlinearity, especially lithium niobate, play a critical role in building optical parametric oscillators (OPOs). However, chip-scale integration of low-loss χ ( 2 ) materials remains challenging and limits the threshold power of on-chip χ ( 2 ) OPO. Here we report an on-chip lithium niobate optical parametric oscillator at the telecom wavelengths using a quasi-phase-matched, high-quality microring resonator, whose threshold power ( ∼ 30 µ W ) is 400 times lower than that in previous χ ( 2 ) integrated photonics platforms. An on-chip power conversion efficiency of 11% is obtained from pump to signal and idler fields at a pump power of 93 µW. The OPO wavelength tuning is achieved by varying the pump frequency and chip temperature. With the lowest power threshold among all on-chip OPOs demonstrated so far, as well as advantages including high conversion efficiency, flexibility in quasi-phase-matching, and device scalability, the thin-film lithium niobate OPO opens new opportunities for chip-based tunable classical and quantum light sources and provides a potential platform for realizing photonic neural networks.

OBJECTIVE The aims of this study were to evaluate image quality of virtual monoenergetic images (VMIs) compared with conventional images (CIs) from spectral detector CT (SDCT) and to explore the optimal energy level in run-off computed tomography angiography (CTA). METHODS The data sets of 35 patients who received run-off CTA on the SDCT were collected in this retrospective study. Conventional images were generated via iterative reconstruction algorithm and VMI series from 40 to 120 keV were generated via spectral reconstruction algorithm. The objective indices including vascular attenuation, noise, signal-to-noise ratio, and contrast-to-noise ratio were compared. Two readers performed subjective evaluation using a 5-point scale. RESULTS The attenuation showed higher values compared with CIs at 40 to 60 keV (P < 0.001). The noise was similar in 60- to 80-keV VMIs and significantly decreased in 90- to 120-keV VMIs (P < 0.001) in comparison with CIs. The signal-to-noise ratio and contrast-to-noise ratio were improved in 40- to 60-keV VMIs compared with CIs (P < 0.05). The score of subjective assessment was higher than that of CIs in 50- to 70-keV VMIs (P < 0.001). CONCLUSIONS Virtual monoenergetic images can provide improved image quality compared with CIs from SDCT in run-off CTA, and VMIs at 60 keV may be the best choice in evaluating lower extremity arteries.