Deep point-based scene labeling with depth mapping and geometric patch feature encoding

This paper presents a deep CNN approach for point-based semantic scene labeling. This is challenging because 3D point clouds do not have a canonical domain and can have complex geometry and substantial variation of sampling densities. We propose a novel framework where the convolution operator is defined on depth maps around sampled points, which captures characteristics of local surface regions. We introduce Depth Mapping (DM) and Reverse Depth Mapping (RDM) operators to transform between the point domain and the depth map domain. Our depth map based convolution is computationally efficient, robust to scene scales and sampling densities, and can capture rich surface characteristics. We further propose to augment each point with feature encoding of the local geometric patches resulted from multi-method through patch pooling network (PPN). The patch features provide complementary information and are fed into our classification network to achieve semantic segmentation

Semantic labeling and instance segmentation of 3D point clouds using patch context analysis and multiscale processing

We present a novel algorithm for semantic segmentation and labeling of 3D point clouds of indoor scenes, where objects in point clouds can have significant variations and complex configurations. Effective segmentation methods decomposing point clouds into semantically meaningful pieces are highly desirable for object recognition, scene understanding, scene modeling, etc. However, existing segmentation methods based on low-level geometry tend to either under-segment or over-segment point clouds. Our method takes a fundamentally different approach, where semantic segmentation is achieved along with labeling. To cope with substantial shape variation for objects in the same category, we first segment point clouds into surface patches and use unsupervised clustering to group patches in the training set into clusters, providing an intermediate representation for effectively learning patch relationships. During testing, we propose a novel patch segmentation and classification framework with multiscale processing, where the local segmentation level is automatically determined by exploiting the learned cluster based contextual information. Our method thus produces robust patch segmentation and semantic labeling results, avoiding parameter sensitivity. We further learn object-cluster relationships from the training set, and produce semantically meaningful object level segmentation.Our method outperforms state-of-the-art methods on several representative point cloud datasets, including S3DIS, SceneNN, Cornell RGB-D and ETH

Reliability assessment of freight wagon passing through railway turnouts using adaptive Kriging surrogate model

Railway turnout (RT) is a crucial component of railway infrastructure that consists of several components. Assessing the derailment probability of freight wagons passing through the turnout is crucial for quantifying failure risks and optimizing the performance of the freight wagon-turnout system (FWTS). However, existing assessment methods often require extensive model evaluations and impose substantial computational costs. To address this issue, an efficient reliability analysis method is established for assessing the derailment risk at RTs. Firstly, a dynamic model is developed to capture the wheel-rail dynamic interaction and the numerical model is validated by field tests. Secondly, to reduce the computational cost in the reliability analysis, an efficient adaptive Kriging method based on an error stopping criteria and a learning function is adopted to estimate the failure probabilities under multiple failure modes of wheel derailments. Based on the efficient learning function and convergence criterion, accurate failure probability results can be obtained with a small number of multibody and finite element coupled dynamic simulations. Furthermore, the prediction accuracy of the proposed method in capturing random characteristics for FWTS is evaluated. Finally, the influence of the evolution of rail wear on the failure probability is further discussed

Enhanced heat transport in thermal convection with suspensions of rod-like expandable particles

Thermal convection of fluid is a more efficient way than diffusion to carry heat from hot sources to cold places. Here, we experimentally study the Rayleigh–Bénard convection of aqueous glycerol solution in a cubic cell with suspensions of rod-like particles made of polydimethylsiloxane. The particles are inertial due to their large thermal expansion coefficient and finite sizes. The thermal expansion coefficient of the particles is three times larger than that of the background fluid. This contrast makes the suspended particles lighter than the local fluid in hot regions and heavier in cold regions. The heat transport is enhanced at relatively large Rayleigh number ( Ra ) but reduced at small Ra . We demonstrate that the increase of Nusselt number arises from the particle–boundary layer interactions: the particles act as ‘active’ mixers of the flow and temperature fields across the boundary layers

Disseminated Tuberculosis Associated Hemophagocytic Lymphohistiocytosis in a Pregnant Woman With Evans syndrome: A Case Report and Literature Review

BackgroundTuberculosis (TB) is a leading cause of morbidity and mortality in underdeveloped and developing countries. Disseminated TB may induce uncommon and potentially fatal secondary hemophagocytic lymphohistiocytosis (HLH). Timely treatment with anti-tuberculosis therapy (ATT) and downmodulation of the immune response is critical. However, corticosteroid treatment for TB-associated HLH remains controversial. Herein, we report a successful case of disseminated TB-associated HLH in a pregnant woman with Evans syndrome accompanied by a literature review.Case PresentationA 26-year-old pregnant woman with Evans syndrome was transferred to the Third Affiliated Hospital of Sun Yat-Sen University because of severe pneumonia. She presented with cough, fever, and aggravated dyspnea. Nested polymerase chain reaction for Mycobacterium tuberculosis (M. tuberculosis) complex in sputum was positive. Sputum smear sample for acid-fast bacilli was also positive. Metagenome next-generation sequencing (mNGS) of the bronchoalveolar lavage fluid identified 926 DNA sequence reads and 195 RNA sequence reads corresponding to M. tuberculosis complex, respectively. mNGS of blood identified 48 DNA sequence reads corresponding to M. tuberculosis. There was no sequence read corresponding to other potential pathogens. She was initially administered standard ATT together with a low dose of methylprednisolone (40 mg/day). However, her condition deteriorated rapidly with high fever, acute respiratory distress syndrome, pancytopenia, and hyperferritinemia. Bone marrow smears showed hemophagocytosis. And caseating tuberculous granulomas were found in the placenta. A diagnosis of disseminated TB-associated HLH was made. Along with the continuation of four drug ATT regimen, therapy with a higher dose of methylprednisolone (160 mg/day) combined with immunoglobulin and plasma exchange was managed. The patient’s condition improved, and she was discharged on day 19. Her condition was good at follow-up with the continuation of the ATT.ConclusionsClinicians encountering patients with suspected TB accompanied by unexplainable inflammation not responding to ATT should consider complications with HLH. Timely administration of ATT combined with corticosteroids may result in a favorable outcome

A two-step lineage reprogramming strategy to generate functionally competent human hepatocytes from fibroblasts

Terminally differentiated cells can be generated by lineage reprogramming, which is, however, hindered by incomplete conversion with residual initial cell identity and partial functionality. Here, we demonstrate a new reprogramming strategy by mimicking the natural regeneration route, which permits generating expandable hepatic progenitor cells and functionally competent human hepatocytes. Fibroblasts were first induced into human hepatic progenitor-like cells (hHPLCs), which could robustly expand in vitro and efficiently engraft in vivo. Moreover, hHPLCs could be efficiently induced into mature human hepatocytes (hiHeps) in vitro, whose molecular identity highly resembles primary human hepatocytes (PHHs). Most importantly, hiHeps could be generated in large quantity and were functionally competent to replace PHHs for drug-metabolism estimation, toxicity prediction and hepatitis B virus infection modeling. Our results highlight the advantages of the progenitor stage for successful lineage reprogramming. This strategy is promising for generating other mature human cell types by lineage reprogramming.</p

Qiliqiangxin Rescues Mouse Cardiac Function by Regulating AGTR1/TRPV1-Mediated Autophagy in STZ-Induced Diabetes Mellitus

Background/Aims: To explore the potential role of qiliqiangxin (QLQX) A traditional Chinese medicine and the involvement of angiotensin II receptor type 1 (AGTR1) and transient receptor potential vanilloid 1 (TRPV1) in diabetic mouse cardiac function. Methods: Intragastric QLQX was administered for 5 weeks after streptozotocin (STZ) treatment. Additionally, Intraperitoneal injections of angiotensin II (Ang II) or intragastric losartan (Los) were administered to assess the activities of AGTR1 and TRPV1. Two-dimensional echocardiography and tissue histopathology were used to assess cardiac function Western blot was used to detect the autophagic biomarkers Such as light chain 3 P62 and lysosomal-associated membrane protein 2 And transmission electron microscopy was used to count the number of autophagosomes. Results: Decreased expression of TRPV1 and autophagic hallmarks and reduced numbers of autophagolysosomes as well as increased expression of angiotensin converting enzyme 1 and AGTR1 were observed in diabetic hearts. Blocking AGTR1 with Los mimicked the QLQX-mediated improvements in cardiac function Alleviated myocardial fibrosis and enabled autophagy Whereas Ang II abolished the beneficial effects of QLQX in wild type diabetic mice but not in TRPV1-/- diabetic mice. Conclusions: QLQX may improve diabetic cardiac function by regulating AGTR1/ TRPV1-mediated autophagy in STZ-induced diabetic mice

Prepregnancy adherence to plant-based diet indices and exploratory dietary patterns in relation to fecundability

Background Modest associations have been reported between specific food groups or nutrients and fecundability [measured by time to pregnancy (TTP)]. Examining overall diets provides a more holistic approach towards understanding their associations with fecundability. It is not known whether plant-based diets indices or exploratory dietary patterns are associated with fecundability. Objectives We examine the associations between adherence to 1) plant-based diet indices; and 2) exploratory dietary patterns and fecundability among women planning pregnancy. Methods Data were analyzed from the Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO) study. Prepregnancy diet was assessed using a semi-quantitative FFQ from which the overall, healthful, and unhealthful plant-based diet indices (oPDI, hPDI, and uPDI, respectively) were calculated. Exploratory dietary patterns were derived using factor analysis based on 44 predefined food groups. Participants were categorized into quintiles based on their dietary pattern scores. TTP (expressed in menstrual cycles) was ascertained within a year from the prepregnancy dietary assessment. Discrete-time proportional hazard models, adjusted for confounders, were used to estimate fecundability ratios (FRs) and 95% CIs, with FR > 1 indicating a shorter TTP. Results Among 805 women, 383 pregnancies were confirmed by ultrasound scans. Compared with women in the lowest quintile, those in the highest quintile of the uPDI had reduced fecundability (FR of Q5 compared with Q1, 0.65; 95% CI, 0.46-0.91; P trend, 0.009). Conversely, greater adherence to the hPDI was associated with increased fecundability (1.46; 95% CI, 1.02-2.07; P trend, 0.036). The oPDI was not associated with fecundability. Among the 3 exploratory dietary patterns, only greater adherence to the Fast Food and Sweetened Beverages (FFSB) pattern was associated with reduced fecundability (0.61; 95% CI, 0.40-0.91; P trend, 0.018). Conclusions Greater adherence to the uPDI or the FFSB dietary pattern was associated with reduced fecundability among Asian women. Greater adherence to the hPDI may be beneficial for fecundability, though this requires confirmation by future studies.Peer reviewe