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Interest in autonomous driving (AD) and intelligent vehicles (IVs) is growing at a rapid pace due to the convenience, safety, and economic benefits. Although a number of surveys have reviewed research achievements in this field, they are still limited in specific tasks and lack systematic summaries and research directions in the future. Our work is divided into three independent articles and the first part is a survey of surveys (SoS) for total technologies of AD and IVs that involves the history, summarizes the milestones, and provides the perspectives, ethics, and future research directions. This is the second part (Part 1 for this technical survey) to review the development of control, computing system design, communication, high-definition map (HD map), testing, and human behaviors in IVs. In addition, the third part (Part 2 for this technical survey) is to review the perception and planning sections. The objective of this article is to involve all the sections of AD, summarize the latest technical milestones, and guide abecedarians to quickly understand the development of AD and IVs. Combining the SoS and Part 2, we anticipate that this work will bring novel and diverse insights to researchers and abecedarians, and serve as a bridge between past and future.

The flow around a square cylinder with a synthetic jet positioned at the rear surface is numerically investigated with the unsteady Reynolds-averaged Navier-Stokes (URANS) method. Instead of the typical sinusoidal wave, a bi-frequency signal is adopted to generate the synthetic jet. The bi-frequency signal consists of a basic sinusoidal wave and a high-frequency wave. Cases with various amplitudes of the high-frequency component are simulated. It is found that synthetic jets actuated by bi-frequency signals can realize better drag reduction with lower energy consumption when appropriate parameter sets are applied. A new quantity, i.e., the actuation efficiency Ae, is used to evaluate the controlling efficiency. The actuation efficiency Ae reaches its maximum of 0.266 8 when the amplitude of the superposed high-frequency signal is 7.5% of the basic signal. The vortex structures and frequency characteristics are subsequently analyzed to investigate the mechanism of the optimization of the bi-frequency signal. When the synthetic jet is actuated by a single-frequency signal with a characteristic velocity of 0.112 m/s, the wake is asymmetrical. The alternative deflection of vortex pairs and the peak at half of the excitation frequency in the power spectral density (PSD) function are detected. In the bi-frequency cases with the same characteristic velocity, the wake gradually turns to be symmetrical with the increase in the amplitude of the high-frequency component. Meanwhile, the deflection of the vortex pairs and the peak at half of the excitation frequency gradually disappear as well.

Lupus nephritis (LN) is an autoimmune glomerulonephritis secondary to systemic lupus erythematosus. Commonly, immunosuppressive agents are required for treating LN. However, frequent use of conventional immunosuppressants may produce a variety of side effects. Hence, seeking alternative drugs for treating LN is very important. This report aims to figure out the immunoregulatory efficacy of celastrol (CLT) in LN.A spontaneous in vivo model of LN was established in FasL-deficient B6/gld mice. ELISA was used for analyzing serum creatinine (Scr) and anti-dsDNA levels in mice. IHC staining, immunofluorescence and hematoxylin-eosin and PAS staining were applied to determine renal immunopathology and histology. Cytokine gene levels were assessed using RT qPCR. CD4+Foxp3+ Treg frequency in murine kidneys, lymph nodes and spleens was determined using flow cytometry analysis.CLT treatment alleviated renal dysfunction and renal injury in LN-prone B6/gld mice. Moreover, CLT reduced CD3+ T cell infiltration and inhibited proinflammatory cytokine expression in renal tissues of B6/gld mice. Importantly, CLT enhanced CD4+FoxP3+ Treg frequency in kidneys, lymph nodes and spleens of B6/gld mice.CLT exerts therapeutic effects on murine LN by improving renal function and immunopathology and inducing CD4+FoxP3+ Tregs.

Most existing trackers use bounding boxes for object tracking. However, the background contained in the bounding box inevitably decreases the accuracy of the target model, which affects the performance of the tracker and is particularly pronounced for non-rigid objects. To address the above issue, this paper proposes a novel hybrid level set model, which can robustly address the issue of topology changing, occlusions and abrupt motion in non-rigid object tracking by accurately tracking the object contour. In particular, an appearance model is first obtained by repeatedly training and relabeling the initial labeled frame using competing one-class SVMs. Then, by integrating the trained appearance model, an edge detector and image spatial information into the level set model, a new hybrid level set model is presented, which accurately locates the object contour and feeds back to the competing one-class SVMs to update the appearance model of the next frame. In addition, a motion model is defined to predict the accurate location of the object when occlusion and abrupt motion occur in the next frame. Finally, the experimental results on state-of-the-art benchmarks demonstrate the feasibility and effectiveness of the proposed model and the superiority of the proposed method over existing trackers in terms of accuracy and robustness.

Synthetic jets have received extensive attention due to their superior mixing property. However, its mechanisms have not been investigated from the perspective of the turbulent/non-turbulent interface (TNTI). To shed new light on this issue, the entrainment and TNTI properties of a synthetic jet are experimentally investigated and compared with a continuous jet at $Re_j = 3150$ . The fuzzy clustering method is applied to select an appropriate vorticity threshold to detect the TNTI. Statistically, it is revealed that the entrainment coefficients of the two jets significantly differ in the near field, while they become almost identical in the far field. Instead of the vortex ring, the ‘breakdown of the vortex ring’ enhances the entrainment in the present synthetic jet. Instantaneously, the TNTI more violently fluctuates in the near field of the synthetic jet, which leads to a larger fluctuation in the TNTI radial position, a higher fractal dimension and enhanced local entrainment. Moreover, the transition of the probability density function of the TNTI orientation from the unimodal distribution in the near field to the bimodal distribution in the far field is found in both jets. The multi-scale analysis reveals a new mechanism for the bimodal distribution caused by the TNTI-thickness-scale structures.

Piezoelectric macro-fibre composite (MFC) actuators are employed onto the flexible leeward surface of an airfoil for active control. Time-resolved aerodynamic forces, membrane deformations and flow fields are synchronously measured at low Reynolds number (Re = 6 × 104). Mean aerodynamics show that the actively controlled airfoil can achieve lift-enhancement and drag-reduction simultaneously in the angle of attack range of 10° ≤ α ≤ 14°, where the rigid airfoil encounters stall. The maximum increments of lift and lift-to-drag ratio are 27.1 % and 126 % at the reduced actuation frequency of ${f^ + } = 3.52$ . The unsteady coupling features are further analysed at α = 12°, where the maximum lift-enhancement occurs. It is newly discovered that the membrane vibrations and flow fields are locked into half of the actuation frequency when ${f^ + } > 3$ . The shift of the dominant vibration mode from bending to inclining is the reason for the novel ‘half-frequency lock-in’ phenomenon. To the fluid–structure interaction, there are three characteristic frequencies for the actively controlled airfoil: $S{t_1} = 0.5{f^ + }$ , $S{t_2} = {f^ + }$ , and $S{t_3} = 1.5{f^ + }$ . Here, St1 and its harmonics (St2, St3) are coupled with the natural frequencies of the leading-edge shear layer, resulting in the generation of multi-scale flow structures and suppression of flow separation. The lift presents comparable dominant frequencies between St1 and St3, which means the instantaneous lift is determined by the flow structures of St1 and St3. The local membrane bulge and dent affect the instantaneous swirl strength of flow structures near the maximum vibration amplitude location, which is the main reason for the variation of instantaneous lift.

Long-term potentiation (LTP) is a key cellular mechanism for learning and memory, and recent studies in the hippocampus found that LTP was impaired in aged animals. Previous studies of cortical LTP have focused primarily on the homosynaptic plasticity in adult mice, while fewer studies have looked at heterosynaptic plasticity - such as synaptic tagging in aged mice. In the present study, we investigated synaptic tagging in the anterior cingulate cortex (ACC) of adult and middle-aged mice by using the 64-channel multielectrode dish (MED64) recording system. We found that synaptic tagging was impaired in the ACC of middle-aged male mice as compared to adult mice. Both the network L-LTP and the recruitment of inactive responses were reduced in the ACC of middle-aged male mice. Similar results were found in female middle-aged mice, indicating that there is no gender difference. Furthermore, bath application of brain-derived neurotrophic factor (BDNF) or systemic treatment with newly developed TrkB receptor agonists R13, was shown to rescue both synaptic tagging, and L-LTP, in middle-aged mice. To determine the distribution of synaptic LTP within the ACC, a new visualization method was developed to map the spatiotemporal variation of LTP in the ACC. Our results provide strong evidence that cortical potentiation and synaptic tagging show an age-dependent reduction, and point to the TrkB receptor as a potential drug target for the treatment of memory decline.

Thiacloprid is a new chlorinated nicotinoid insecticide against stinging-oral pests, such as aphids. It is less toxic to bees but more toxic to earthworms. In this study, a pH- and amylase-responsive MOF (ZIF-8) was constructed for site-specific delivery of thiacloprid to control pea aphids and more safety for earthworms. Thiacloprid from α-cyclodextrin@Thiacloprid@ZIF-8 (α-CD@T@ZIF-8) could be released quickly in pea aphids, which was ascribed to disintegration of ZIF-8 at low pH values in pea aphid intestines and degradation of α-CD under the action of α-amylase. The release results showed a significant pH dependence of α-CD@T@ZIF-8, with an approximately 65 % release amount at pH = 7 and a 95 % release amount at pH = 5 for 7 d. The results of the pot experiment and biosafety showed that for α-CD@T@ZIF-8, 88 % pea aphids could be killed compared with 32 % aphids for commercially available formulation on the 7th day after application. Meanwhile the LC

Background The anti-cancer activities of tripterine in human cells offer promising therapeutic solutions to patients living with cancer. However, the effects of tripterine on breast cancer (BC) have not been closely examined. This study was to investigate the underlying biological pathway through which tripterine and miR-184 influence BC progression. Methods Two human BC cell lines (MCF-7 and BT-474) were cultured in this study. Different concentrations of tripterine (0, 5, 10 and 15 μM) were dissolved in dimethyl sulfoxide (DMSO) and then added to the cells. The expression of miR-184 was measured using qRT-PCR. The inhibitory impact of tripterine and miR-184 on BC development was assessed by CCK-8, BrdU, transwell, and wound healing assays. Western blot assay was also performed to analyze Bax and Bcl-2 protein expression of BC cells. Results Findings indicated that tripterine suppressed BC cells' viability, proliferation, migration, invasion capacity and Bcl-2 protein expression, but it induced BC cells’ Bax protein expression. It was also found miR-184 expression was high in the BC cell lines treated with tripterine and that miR-184 overexpression reduced the viability, proliferation, and invasion abilities of BC cells under tripterine treatment. Interference with miR-184 neutralized the effects of tripterine on BC cell viability, proliferation and invasion. Conclusion This research suggested that by interacting with miR-184, tripterine could restrain the progression of BC. This knowledge could be instrumental in developing highly effective treatment solutions for BC.

Background Fibroblasts are important structural cells in synovium and play key roles in maintaining the synovial homeostasis. By single-cell RNA sequencing (scRNA-seq), subpopulation of synovium-resident cells has been reported to protect intra-articular structures from chronic inflammation and promote tissue repair. However, a significant number of researchers have concentrated on the role of fibroblasts in the progress of rheumatoid arthritis (RA) while few reports had described the contribution of distinct fibroblast subsets in the RA remission. It is helpful to understand the role of fibroblast subpopulations in the RA process to provide predictive biomarkers and address RA remission mechanisms. Here, we found HBEGF+ fibroblasts that contributed to RA remission by integrating scRNA-seq datasets and bulk RNA sequencing (bulk RNA-seq) datasets. Method Three single-cell RNA datasets of cells harvested from RA patients were processed and integrated by Seurat and Harmony R packages. After identifying cell types by classic marker genes, the integrated dataset was used to run CellChat for analysis of cell-cell communication. Specially, EGF signaling pathway was found and HBEGF+ fibroblasts were identified based on HBEGF expression. Differential expressed genes of HBEGF+ were shown in heatmap and volcano plot and used to run gene ontology (GO) enrichment analysis. Next, bulk RNA-seq datasets of synovium under different conditions (health, osteoarthritis (OA), rheumatoid arthritis, before and after classical treatment) were compared to show expression change of HBEGF and gene markers that are mainly expressed by HBEGF+ fibroblasts such as CLIC5, PDGFD, BDH2, and ENPP1. Finally, two single-cell RNA sequencing datasets of synovial cells from mice were integrated to identify Hbegf+ fibroblasts and calculate the population of Hbegf+ fibroblasts under different joint conditions (health, K/BxN serum transfer arthritis (STA), and remission of STA). Result After integrating three single-cell RNA sequencing datasets, we identified 11 clusters of synovial cells, such as fibroblasts, mural cells, endothelial cells, CD4+ T cells, CD8+ T cells, natural killer cells, synovium macrophage, peripheral blood macrophages, plasma cells, B cells, and STMN1+ cells. We found fibroblasts had an extensive communication network with other clusters and interacted with synovial macrophages through EGF signaling pathway via analysis of cell-cell communication between synovial cells. HBEGF, ligand to EGF signaling pathway, was highly expressed by a subset of fibroblasts and macrophages, and EGFR, receptor to EGF signaling pathway, was highly expressed by fibroblasts and meniscus cells. Moreover, HBEGF was downregulated under RA state and it had an increase after classical treatment. We then defined fibroblasts with high expression of HBEGF as HBEGF+ fibroblasts. In addition, we also found that HBEGF+ fibroblasts highly expressed CRTAC1, ITGB8, SCARA5, THBS4, and ITGBL1, genes relative to encoding extracellular matrix proteins and engaged in positive regulation of cell migration and motility, cellular component movement, and cell growth by GO enrichment analysis. We eventually identified HBEGF+ fibroblasts specially expressed CLIC5, PDGFD, BDH2, and ENPP1, which positively correlated with the expression of HBEGF. Moreover, the expression of CLIC5, PDGFD, BDH2, and ENPP1 was downregulated under RA state and elevated by classical therapy. On the contrary, the HBEGF+ macrophages specially expressed SLAMF8, GK, L1RN, and JAK2, which negatively correlated with the expression of HBEGF. The expression was upregulated in SLAMF8, GK, L1RN, and JAK2 under the RA state, whereas it was decreased after classical treatment. In mice, the number of Hbegf+ fibroblasts was reduced in the RA synovium but increased in the RA remitting synovium. Conclusions HBEGF+ fibroblasts play a role in the remission of rheumatoid arthritis, and HBEGF has potential to become a novel biomarker for prediction of RA progress.

The data demonstrated that a transgenic murine model of primary biliary cholangitis (PBC), expressing dominant negative TGF-β receptor Ⅱ (dnTGFβRⅡ) under the CD4 promoter, showed similarity to PBC patients that is female-dominant. Female dnTGFβRII mice developed more severe lymphocytic infiltration in the liver and had higher levels of inflammatory cytokines, including IFN-γ and TNF-α, than the male mice. Interestingly, elimination of testosterone through gonadectomy in male dnTGFβRII mice did not influence disease severity, supporting that testosterone is an unessential factor in sustaining liver immune homeostasis. Meanwhile, it was observed that treating dnTGFβRII mice with oral antibiotics markedly reduced the differences in the levels of lymphocytic infiltration and cytokines between males and females, suggesting that the commensal gut microbiome plays a role in determining the observed sexual differences in dnTGFβRII mice. Furthermore, the diversity of gut microbiota composition and their metabolic functions in the male and female groups through metagenomic sequencing analysis were identified. The results revealed a testosterone-independent and commensal gut microbiota-mediated female bias in PBC.

Since the beginning of the COVID-19 pandemic outbreak, medical texts on the pandemic have enjoyed wide popularity, and one of the key issues has always been the accuracy and dependability of the information they contain. The use of evidentiality, a linguistic system which functions to indicate the source and credibility of information, is thus worth exploring in COVID-19 texts. Adopting a synthesized framework within the overall model of systemic functional linguistics, this paper sets out to investigate the lexicogrammar and semantics of evidentiality on the basis of data collected in the form of both specialized and popular texts on COVID-19. Evidentiality in these texts is explored along four dimensions: (i) evidential taxonomy, where specialized texts favor reporting, while popular texts favor belief and inferring; (ii) information source, where specialized texts highlight the voices of authorship, original research, and patients, whereas popular texts highlight the voices of scientists, institutions, countries, and laypeople; (iii) modalization, where specialized texts typically indicate a higher degree of modal responsibility than their popular counterparts; and (iv) engagement, where specialized texts favor dialogic expansion and popular texts favor contraction. It is hoped that these findings will shed light on linguistic variation according to different contextual configurations, as well as clarifying rhetorical conventions in discourse communities of science.

The mild, efficient, and straightforward synthesis of pharmaceutically and biologically active N3-substituted and N1,N3-disubstituted quinazoline-2,4-(1H,3H)-diones from simple and readily available substrates has been a huge challenge. Described here is a Pd(II)-catalyzed [4 + 1 + 1] modular synthesis of diverse quinazoline-2,4-(1H,3H)-diones through one-pot cascade reactions of cyclocondensation of o-(alkyl)aminobenzoic acids with CO, amidation of the intermediate isatoic anhydrides with amines, and unprecedented carbonylation of the resulting o-aminobenzamides with CO under 1 atm and 60 °C conditions. The chemoselective and versatile multicomponent reaction allows for the diversities of the products including N3-substituted and N1,N3-disubstituted products, and even makes the substituents on N1,N3 the same or different from each other, which cannot be achieved by most traditional synthetic strategies.

Most of the existing Multi-Object Tracking (MOT) approaches follow the Tracking-by-Detection and Data Association paradigm, in which objects are firstly detected and then associated in the tracking process. In recent years, deep neural network has been utilized to obtain more discriminative appearance features for cross-frame association, and noticeable performance improvement has been reported. On the other hand, the Tracking-by-Detection framework is yet not completely end-to-end, which leads to huge computation and limited performance especially in the inference (tracking) process. To address this problem, we present an effective end-to-end deep learning framework which can directly take image-sequence/video as input and output the located and tracked objects of learned types. Specifically, a novel global response network is learned to project multiple objects in the image-sequence/video into a continuous response map, and the trajectory of each tracked object can then be easily picked out. The overall process is similar to how a detector inputs an image and outputs the bounding boxes of each detected object. Experimental results based on the MOT16 and MOT17 benchmarks show that our proposed on-line tracker achieves state-of-the-art performance on several tracking metrics.

Physical representation of coherent motions in wall-bounded turbulence satisfying Townsend's attached-eddy hypothesis (AEH) is still an open question to be debated. Here, we apply proper orthogonal decomposition (POD) to instantaneous snapshots of $u$ component velocity fields in the streamwise–wall-normal plane of three turbulent boundary layers, which cover a frictional Reynolds number ( $Re$ ) of $Re_\tau \approx 1000{\sim} 4000$ and were either measured by large-field-of-view planar particle image velocimetry or calculated by direct numerical simulation. The $u$ component POD modes characterized by streamwise recurring large-scale motions are decomposed into wall-attached and wall-detached parts depending on the wall-attachment condition. The former, i.e. wall-attached POD eddies, are believed to be the prime statistical representations of attached eddies. The reason lies in three aspects. Firstly, wall-attached POD eddies are geometrically self-similar and statistically independent. Secondly, the wall-normal variation of the variance of reduced-order streamwise velocity components $\tilde {u}_{AE}$ , which is only contributed by wall-attached POD eddies, presents logarithmic decay in the inertial flow region. Thirdly, analysis on the scaling behaviour of the high-even-order moment, moment generating function, as well as longitudinal two-point structure function, all indicate a quasi-Gaussian behaviour of $\tilde {u}_{AE}$ . None of these AEH-predicted behaviours are evident when the contribution of superstructure-like POD eddies are considered. Furthermore, wall-detached POD eddies are found to also present quasi-Gaussian behaviour. They might be treated as passive fragments of wall-attached ones.

This case report describes a 63-year-old male, who was admitted to the hospital due to “the ulceration in his left lower limb for more than 1 month and the pain exacerbation for 2 weeks”. The patient was diagnosed with “cerebral infarction, coronary heart disease and type 2 diabetes” nine years ago and subsequently treated with coronary artery bypass graft surgery. This time, he was admitted with an ulcer in the size of 4*45cm on the inner side of his left lower limb, with the wound covered by a dark scab, and the skin was red and swollen around the part where the pus percolated. According to the occlusion in the initiating terminal of his left superficial femoral artery, and the extensive stenosis and occlusion in popliteal and infrapopliteal arteries, this patient was diagnosed with arteriosclerosis obliterans of lower limbs, as shown by the Digital Subtraction Angiography (DSA). Therefore, on the basis of supportive medical treatment and local debridement, he underwent two endovascular operations to open the “straight bloodstream” towards the affected part. Then, the 4-month sequential treatment of split-thickness skin and tissue-engineered skin grafts combined with Negative Pressure Wound Therapy (NPWT) was performed for wound repair. Finally, the wound healed completely, recovering the patient’s ability to walk with a walking aid. This was the first time that the sequential treatment, including Percutaneous Transluminal Angioplasty (PTA), autologous skin and tissue-engineered skin grafts, and negative pressure suction, was successfully used to cure a refractory ulcer in the donor site after the patient with critical limb ischemia received the coronary artery bypass graft surgery.

This case report is concerned with a female patient aged 62, who was admitted to the hospital due to the “ulceration on her left foot for more than one month and the pain exacerbation for one week”. Three years ago, this patient underwent regular hemodialysis for treating the “renal failure in the stage of uremia”. This time, she was admitted with plantar and heel ulcers on her left foot, which had caused damage to the lower leg. The digital subtraction angiography (DSA) showed extensive stenosis and occlusion in the left superficial femoral artery, left peroneal artery and left posterior tibial artery, based on which this patient was diagnosed with type 2 diabetic foot ulcers (DFU, TEXAS 4D). After her admission to the hospital, the multidisciplinary team (MDT) concluded from discussion that the flap transposition and transfemoral amputation were not applicable to this case. Therefore, the “straight bloodstream” was opened by endovascular operation towards the affected part on the basis of medical supportive treatment + local debridement. Then, the wound was sequentially repaired by split-thickness skin and tissue-engineered skin grafts combined with negative pressure treatment. Four months later, the wound completely healed, and the patient was able to walk with walking aid. It was the first case in which the ischemic diabetic plantar and heel ulcers were successfully cured by the sequential treatment involving percutaneous transluminal angioplasty (PTA), autologous skin and tissue-engineered skin grafts, and negative pressure suction.

Studies on the high-lift mechanisms of butterfly gliding flights shed light on the design of the micro air vehicles. The flow field around a simplified Danaus plexippus model is investigated using the hydrogen bubble visualization and the Particle Image Velocimetry (PIV) techniques. There are three near-wall topological patterns with different Angles of Attack (AoAs): the separation bubble, the Leading-Edge Vortex (LEV) and the high AoAs flow. For the separation bubble pattern, two saddles and two foci form in the middle of the model. The features of the LEV pattern are the leading-edge separation lines. The topological characteristics of the separation lines are changed by the interaction between the LEV and the Wing-Tip Vortex (WTV). For the high AoAs flow pattern, four unstable foci are found at the forewing and the hindwing respectively. The angle between the trajectory of the WTV and the model increases with increasing AoA even though the slope of the WTV angle versus AoA curve declines at the moderate AoAs.

Purpose Hepatocellular carcinoma (HCC) is the most common primary liver tumor and the third greatest cause of cancer-related death worldwide. Programmed cell death 4 (PDCD4) was reported as a potential tumor-suppressor in hepatocarcinogenesis. However, relatively little is known about mechanisms that regulate PDCD4 expression in HCC. The aim of the present study is to investigate the expression of PDCD4 and miR-182 in human HCC cell lines and clinical HCC specimens and determine whether PDCD4 is a direct target of miR-182 in HCC cell lines. Materials The expression of miR-182 and PDCD4 in human HCC cell lines and HCC tissues were examined using qRT-PCR and Western blot method. Transwell and wound healing assays were carried out to explore the influence of miR-182 on hepatoma cells migration. A luciferase reporter assay was conducted to confirm target association. Results In our research, we found that PDCD4 was downregulated, whereas miR-182 was upregulated in liver cancer cell lines and HCC tissues. Transwell and wound healing assays illustrated that miR-182 contributed to migration activities of liver cancer cell lines. Loss or increase of miR-182 can lead to a negative expression of PDCD4 protein level. The luciferase reporter assay showed that PDCD4 is a direct target of miR-182. Conclusion All these findings suggest that miR-182 may act as an oncogenic role in liver cancer cells by directly and negatively regulating expression of PDCD4.

Mineral dust suspended in the atmosphere has significant effects on radiative balance and climate change. The Chinese Loess Plateau (CLP) is generally considered one of the main sources of Asian dust aerosol. After being lifted by wind, dust particles with various size distributions can be transported over different distances. In this study, an original loess sample was collected from Luochuan, which is centrally located on the CLP, and two samples with different size distributions were obtained afterwards. “Pristine loess” was used to represent dust that only affects source regions, part of pristine loess was milled to finer “milled loess” that can be transported over long distances. Light scattering matrices for these two samples were measured at 532 nm wavelength from 5 to 175∘ angles. Particle size distribution, refractive index, chemical component, and microscopic appearance were also characterized for auxiliary analyses. Experimental results showed that there are obvious discrepancies in angular behaviors of matrix elements for pristine loess and milled loess, and these discrepancies are different from those for other kinds of dust with distinct size distributions. Given that the effective radii of these two loess samples differ by more than 20 times, it is reasonable to conclude that the difference in size distributions plays a major role in leading to different matrices, while differences in refractive index and microstructure have relatively small contributions. Qualitative analyses of numerical simulation results of irregular particles also validate this conclusion. Gaussian spheres may be promising morphological models for simulating the scattering matrix of loess but need further quantitative verification. Finally, synthetic scattering matrices for both pristine loess and milled loess were constructed over 0–180∘, and the previous average scattering matrix for loess dust was updated. This study presents measurement results of Chinese loess dust and an updated average scattering matrix for loess, which are useful for validating existing models, developing more advanced models for optical simulations of loess dust, and helping to improve retrieval accuracy of dust aerosol properties over both source and downwind areas.

Welding thermal cycles with different peak temperatures were reproduced by a Gleeble testing machine to simulate the heat-affected zone of a Ni-17Mo-7Cr superalloy-welded joint. The effects of the thermal cycle times and peak temperatures on the microstructure and tensile properties of the thermal simulation specimens were systematically studied. The results show that no eutectic carbides are observed below 1300 °C, even when the number of thermal cycles is increased to 5. However, the eutectic reaction occurs above 1300 °C and causes a significant change in the carbide morphology because it transforms from a granular to lamellar structure. Moreover, the carbide composition transforms from (Ni, Cr)3Mo3C for the primary carbides to Ni3(Mo, Cr)3C for the lamellar carbides after the eutectic reaction. Tensile tests show that the thermal cycle has a minor effect on the tensile properties, except when the specimen underwent 5 thermal cycles with a peak temperature of 1340 °C. This is mainly due to the severe liquation reaction caused by elevated temperatures from the welding heat source, which induces cracking along the grain boundaries and results in a degradation of the tensile properties.

Previous studies have shown that vortex rings impinging onto porous walls will pass through the wall more easily as the vortex ring strength, wall porosity, and pore size increase and the wall thic...

Disruption of tissue homeostasis often results in many diseases. Balanced control of stem cell proliferation and differentiation underlines tissue homeostasis. However, how endogenous factors influence the proliferation and differentiation of intestinal stem cells (ISCs) under physiological conditions remains not fully understood. Here, we find that the endoplasmic reticulum membrane protein complex (EMC) negatively regulates ISC proliferation in adultDrosophilamidgut. Compromising EMC function in progenitors leads to excessive ISC proliferation and intestinal homeostasis disruption. Mechanistically, the EMC complex associates with and stabilizes Hippo (Hpo), the key component of the Hpo signaling pathway. In the absence of the EMC complex, Yki (Yorkie) is activated to promote ISC proliferation. Furthermore, the role of the EMC complex in stem cell proliferation control is evolutionarily conserved. Thus, our study uncovers the molecular mechanism of the EMC complex in controlling stem cell proliferation. Our results provide new insight into the underlying mechanisms of how stem cell proliferation is properly controlled under physiological conditions.

Primary biliary cirrhosis (PBC) is an organ-specific autoimmune disease that eventually develops into cirrhosis and even liver cancer. In recent years, the incidence rate has been increasing, and the early diagnosis and treatment of PBC are crucial. In the early diagnosis method of PBC, anti-mitochondrial antibodies (AMAs) are an important diagnostic basis, especially the M2 subtype (AMA-M2) with almost 100% specificity. We selected the BCOADC-E2 protein, a mitochondrial autoantigen that reacts specifically with AMA-M2 antibodies, and carried out DNA recombination and protein mutation experiments by cloning in vitro the homologous target gene sequence BCKD that expresses the antigenic epitope of BCOADC-E2 protein, to provide experience for later exploring the effect of mutations of amino acids around the lysine in the active center of BCOADC-E2 protein on its specific binding to AMA-M2, and to lay the foundation for determining the key amino acids of BCOADC-E2 for the diagnosis and treatment of PBC. In addition, we apply this scientific research content to graduate course teaching. Experimental technology of microbial molecular ecology is a course with the cross-integration of multidisciplinary knowledge and experimental skills offered at our college since 2018. This article derives from the part of this course on the construction of recombinant plasmids. The students first constructed the recombinant plasmid pGEX-BCKD using the vector plasmid pGEX-4T1 and the target gene fragment BCKD provided by the laboratory and used this as a template to construct the pGEX-BCKD-E4A point mutation plasmid by the overlap extension PCR (SOE PCR) technique to achieve the effect of mutating the fifth amino acid glutamate in front of lysine, the active centre of the BCOADC-E2 lipid acyl binding domain, to alanine for subsequent studies. Through the research experiment, combining theoretical knowledge and experimental operation, we aim to deepen the student’s understanding of DNA recombination technology, let them feel the practical application prospect of experimental technology, stimulate students’ interest in professional knowledge learning, and cultivate students’ scientific thinking and innovation consciousness. We examined the quality of the teaching through the process and summative evaluation of the students. In this study, the students successfully completed the construction of pGEX-BCKD-E4A point mutant plasmid, and the average test score increased from 40.4% before teaching to 91.1%. The teaching effect was remarkable. This kind of research experimental teaching mode has good application prospects, and other education and teachers can refer to and reference it.

Synthetic jets generated by four typical and two novel exciting signals are simulated in the present study. Vortex structures and velocity characteristics are analyzed in detail to evaluate the effectiveness of the exciting signal. The synthetic jets excited with the four typical signals, i.e., the triangle signal, sinusoidal signal, trapezoid signal, and square signal, are simulated in the first place. It is found that stronger synthetic jets and higher entrainment can be realized by signals with higher peak velocity. Among the typical signals, the most satisfactory performance is observed in the case of the triangle signal. Two novel signals, i.e., the bi-frequency signal and the signal with varying duty cycle k, are subsequently simulated. The numerical result shows that, even with the same peak velocity, the two novel signals have better performance than the triangle signal. The optimal result is achieved in the case of the varying k signal. The signal momentum msignal is used to fundamentally explain the mechanism behind the different performances of the synthetic jets generated with different signals with the same characteristic velocity. The parameter, i.e., characteristic momentum Msignal, is subsequently utilized to represent the performances of the different signals. The synthetic jets generated with the signals of higher characteristic momentum are found to manifest better performance under the condition of the same frequency and characteristic velocity.