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With the prevalent use of LiDAR sensors in autonomous driving, 3D point cloud object tracking has received increasing attention. In a point cloud sequence, 3D object tracking aims to predict the location and orientation of an object in consecutive frames. Motivated by the success of transformers, we propose Point Tracking TRansformer (PTTR), which efficiently predicts high-quality 3D tracking results in a coarse-to-fine manner with the help of transformer operations. PTTR consists of three novel designs. 1) Instead of random sampling, we design Relation-Aware Sampling to preserve relevant points to the given template during subsampling. 2) We propose a Point Relation Transformer for effective feature aggregation and feature matching between the template and search region. 3) Based on the coarse tracking results, we employ a novel Prediction Refinement Module to obtain the final refined prediction through local feature pooling. In addition, motivated by the favorable properties of the Bird’s-Eye View (BEV) of point clouds in capturing object motion, we further design a more advanced framework named PTTR++, which incorporates both the point-wise view and BEV representation to exploit their complementary effect in generating high-quality tracking results. PTTR++ substantially boosts the tracking performance on top of PTTR with low computational overhead. Extensive experiments over multiple datasets show that our proposed approaches achieve superior 3D tracking accuracy and efficiency.

As induction motor is one of the most preponderant driving equipment in modern industrial systems, timely detection and maintenance of motor failures can efficaciously circumvent economic losses and catastrophic accidents. Though vast majority of machinery fault diagnosis approaches are based on vibration analysis, there may be circumstances that it is impossible to install vibratory sensors in some sophisticated equipment or harsh environments. In view of this, a fault diagnosis method for induction motor based on multiscale acoustic entropy feature selection and hierarchical adaptive neuro-fuzzy inference system (HANFIS) with localized recurrent input is presented in this article. First, multiscale entropy features, which can reflect the health state of the running motor, are extracted from the collected acoustic signals. Subsequently, to avoid the dimensionality disaster problem and remove irrelevant features, the Relief-F algorithm is used for feature selection. Next, based on the fuzzy formalisms, a newly designed HANFIS is utilized for motor fault identification, where the localized recurrent input mechanism allows for injecting important features again into the model to prevent it from forgetting significant discriminative information, to further promote the overall diagnostic accuracy. Finally, experiments on two acoustic datasets of induction motor and comparisons with existing approaches sufficiently verify the effectiveness and superiority of the proposed method.

Device to device (D2D) is becoming one of the critic technologies of green smart cities. The uplink power allocation is investigated, when D2D users reuse subchannels of cellular users. The overall goal lies in minimization of energy consumption under guarantee of required data transmission rate, which belongs to a nondeterministic polynomial (NP) hard optimization problem. After analysis, we find that the constraint has implicit monotonicity, so we introduce a new vector to transform it into a monotonic optimization problem. Then, the equivalence of the problem before and after transformation is proved. To search global optimal energy conservation solution, we design a novel power allocation algorithm based on principle of reverse polyblock approximation and prove its convergence. It is demonstrated that our proposal is able to reduce power consumption in comparison to the most advanced alternatives. The proposed algorithm can be used as a benchmark to evaluate other algorithms.

Bisphenol A (BPA) is a ubiquitous man-made endocrine disrupting compound (EDC). Developmental exposure to BPA changes behavioral and reproductive phenotypes, and these effects can last for generations. We exposed embryos to BPA, producing two lineages: controls and BPA exposed. In the third filial generation (F3), brain tissues containing the preoptic area, the bed nucleus of the stria terminalis, and the anterior hypothalamus were collected. RNA sequencing (RNA-seq) and subsequent data analyses revealed 50 differentially regulated genes in the brains of F3 juveniles from BPA vs control lineages. BPA exposure can lead to loss of imprinting, and one of the two imprinted genes in our data set, maternally expressed gene 3 (Meg3), has been associated with EDCs and neurobehavioral phenotypes. We used quantitative polymerase chain reaction to examine the two imprinted genes in our data set, Meg3 and microRNA-containing gene Mirg (residing in the same loci). Confirming the RNA-seq, Meg3 messenger RNA was higher in F3 brains from the BPA lineage than in control brains. This was true in brains from mice produced with two different BPA paradigms. Next, we used pyrosequencing to probe differentially methylated regions of Meg3. We found transgenerational effects of BPA on imprinted genes in brain. Given these results, and data on Meg3 methylation in humans, we suggest this gene may be a biomarker indicative of early life environmental perturbation.

Phthalates are used in consumer products and are known endocrine-disrupting chemicals. However, limited information is available on the effects of phthalate mixtures on female reproduction. Previously, we developed a phthalate mixture made of 35% diethyl phthalate, 21% di(2-ethylhexyl) phthalate, 15% dibutyl phthalate, 15% di-isononyl phthalate, 8% di-isobutyl phthalate, and 5% benzylbutyl phthalate that mimics human exposure. We tested the effects of prenatal exposure to this mixture on reproductive outcomes in first-filial-generation (F1) female mice and found that it impaired reproductive outcomes. However, the impact of this exposure on second-filial-generation (F2) and third-filial-generation (F3) females was unknown. Thus, we hypothesized that prenatal exposure to the phthalate mixture induces multigenerational and transgenerational effects on female reproduction. Pregnant CD-1 dams were orally dosed with vehicle (tocopherol-stripped corn oil) or a phthalate mixture (20 and 200 µg/kg/d, 200 and 500 mg/kg/d) daily from gestational day 10 to birth. Adult F1 females born to these dams were used to generate the F2 generation and adult F2 females born to F1 females were used to generate the F3 generation. F2 and F3 females were subjected to tissue collections and fertility tests. Prenatal phthalate mixture exposure increased uterine weight, anogenital distance, and body weight; induced cystic ovaries; and caused fertility complications in the F2 generation. It also increased uterine weight, decreased anogenital distance, and caused fertility complications in the F3 generation. These data suggest that prenatal exposure to the phthalate mixture induces multigenerational and transgenerational effects on female reproduction.

Large-depth and multiscale gradient microstructure in dual-phase Al0.6CoCrFeNi high entropy alloy (HEA) were fabricated by explosion hardening (EH) technique. The gradient microstructure evolution was investigated in detail. The microhardness distribution and tensile properties near EH affected surface were also determined. The formation and strengthening mechanisms of gradient microstructure after EH treatment were subsequently analyzed. Experimental results showed that the multiscale gradient microstructure in terms of grain size, phase morphology, dislocation structure, texture was induced in dual-phase (BCC+FCC) HEA by EH technique. The closer to EH affected surface, the finer grain size, higher dislocation density and stronger texture intensity. The deformation and break of spinodal decomposition and formation of new grain boundaries by dislocation structure contributed to grain refinement and transition of equiaxed grains to dendritic grains from lower area to EH affected surface. After EH treatment, the microhardness generally increased with a maximum increase of ∼67% within 5 mm from EH affected surface, the tensile yield stress increased from 320 MPa to maximum of 700 MPa. The strengthening mechanism is different at various depth positions: near EH affected surface, the main strengthening mechanism is high-density dislocations, stacking faults and grain refinement; in areas relatively far from EH affected surface, only dislocation structure contributed to the strengthening of mechanical properties.

A series of oxides with high rare earth contents, RE3TeBO9(RE = La, Pr, Nd, Sm-Dy), were synthesized, and they all crystallize in the noncentrosymmetric space group P63resembling that of a previously reported Bi3TeBO9(J. Am. Chem. Soc.2016, 138, 14190–14193), which showed a very strong second harmonic generation (SHG) signal believed to come from all three structural units [BO3], [TeO6], and [BiO6]. Surprisingly, compared with the isostructural compound Bi3TeBO9, both theoretical calculations and powder SHG tests show that RE3TeBO9has an abnormally small SHG effect (0.2 × KDP). Based on the group theory analysis, the possible reasons are attributed to the misalignments and lack of distortions of the [BO3], [TeO6], and [REO8] groups in the unit cell. The 21symmetric operation (a subset operation of the 63-screw axis) of the [TeO6], [BO3], and [REO8] groups leads to complete cancellation of their contributions to the xydirections, while the absence of lone pair electrons in RE3+and Te6+results in small distortion in the caxis, hence small contributions to the SHG coefficients dijkinvolving the zaxis. Diffuse reflectance spectra of RE3TeBO9(RE = La, Pr, Nd, Sm-Dy) show typical absorption of different RE3+, and the similarity of their infrared spectra is due to the same crystal structure and same structural units of the [TeO6] and [BO3] groups. The strong fluorescence intensities of Eu3TeBO9and Tb3TeBO9show the characteristic emissions of Eu3+and Tb3+, which may serve as luminescence materials with proper doping.

It is imperative to design and fabricate a high-performance free-standing electrode to meet the demand for flexible energy-storage devices with the development of wearable and portable electronics. CuS is an impressive candidate as an ideal pseudo-capacitance material due to its high theoretical capacity, easy preparation and wide source of raw materials. However, the low conductivity of CuS limits its application. Herein, polyaniline (PANI) was coated on CuS @ functional carbon cloth (fCC) to address the inherent defects of CuS using a facile polymerization procedure. Nano-scale PANI arrays with excellent conductivity grown on super-hydrophilic fCC provide a superior electroactive surface and facilitate electron transfer and electrolyte diffusion, which enhance the electrochemical performance of free-standing electrode. The as-prepared PANI/CuS@fCC electrode exhibits outstanding areal capacitance of 2167.2 mF cm−2at 0.5 mA cm−2, impressive capacitance retention rate (89.2 %) after 5000 cycles at 5 mA cm−2, and satisfactory mechanical properties and flexibility. The assembled symmetrical supercapacitor also exhibits significant rate capacity with a specific capacitance of 816.4 mF cm−2, a high energy density of 0.268 mW h cm−2at 0.5 mW cm−2and stable cycle performance with a capacitance retention rate exceeding 98 %. This study provides an effective strategy to fabricate advanced and flexible supercapacitor electrode.

Background: Transplantation of mesenchymal stem cells (MSCs) alters the ventricular electrophysiologic properties after myocardial infarction (MI) in rats. However, it is unclear whether MSCs transplantation enhances the secretion of nerve growth factor (NGF) and affects cardiac sympathetic remodeling. Methods: MI was induced in 35 male Sprague-Dawley rats. Two weeks later, the animals were randomized to MSCs or phosphate buffer solution (PBS) injections into the infarcted myocardium. Six weeks thereafter, the expressions of NGF, growth associated protein 43 (GAP43) and tyrosine hydroxylase (TH) were measured and the density of GAP43 and TH positive nerves was calculated in the borderzone. NGF levels were detected in different culture conditions with neonatal rat ventricular myocytes (NRVMs, 2×105/well) and MSCs (2×105/well). Results: Compared with PBS, mRNA expression and protein levels of NGF, GAP43 and TH increased in the border zone after MSCs injection. Immunohistochemistry showed more GAP43- and TH-positive nerves in the MSCs than in the PBS group. Compared to monocultured MSCs, mono-cultured NRVMs secreted more NGF in vitro. Conclusions: The expression of NGF increased after MSCs transplantation, which may affect sympathetic remodeling and the electrophysiological properties after MI. Paracrine factors secreted by MSC-CM may be involved in this process.

The loss of superhydrophobicity due to mechanochemical damage is critical for superhydrophobic surfaces, and rapid self-healing is significant in maintaining surface durability. Herein, a novel, fast, self-healing superhydrophobic sponge capable of all-weather heating was polymerized in an eco-friendly aqueous system and dip-coated using fluorine-free and non-toxic reagents. Benefiting from the photothermal and Joule-heating performance of polyaniline (PANI) and multiwalled carbon nanotubes (MWCNTs), all-weather heating could be achieved. The equilibrium surface temperature (EST) of the as-prepared sponge could rapidly reach 105°C under irradiation of 1.0 kW/m2 for 20 s, and the EST exceeded 120°C with supplementary 18 V treatment. Impressively, after O2plasma etching for 1 min or after being immersed in hydrogen peroxide (H2O2) solution for 24 h, the water contact angle (WCA) of self-healing superhydrophobic polyurethane (PU) sponge (SHSPS) can be restored to 155°C under simulated sunlight for 2 min because of the rapid migration of low surface energy polydimethylsiloxane (PDMS) chains, which is the fastest recovery achieved to the best of our knowledge. In addition, the modified sponge exhibited a significant antifouling capability for particulate contaminants and organic pollutants, extending service life. Our preliminary results demonstrated that the modified sponge prepared in the current work is fully qualified in multiple applications, including oil-water separation, viscous oil treatment, seawater evaporation and desalination, de-icing, and anti-icing.

Endocrine-disrupting chemicals (EDCs) are found abundantly in the environment, resulting in daily human exposure. This is of concern because many EDCs are known to target the female reproductive system and, more specifically, the ovary. In the female, the ovary is the key organ responsible for reproductive and endocrine functions. Exposure to EDCs is known to cause many reproductive health problems such as infertility, premature ovarian failure, and abnormal sex steroid hormone levels. Some EDCs and their effects on adult ovarian function have been studied extensively over the years, whereas the effects of others remain unclear. This review covers what is currently known about the effects of selected EDCs (bisphenol A, methoxychlor, 2,3,7,8-tetrachlorodibenzo-p-dioxin, phthalates, and genistein) on the adult ovary and the mechanisms by which they act upon the ovary, focusing primarily on their effects on folliculogenesis and steroidogenesis. Furthermore, this review discusses future directions needed to better understand the effects of EDCs, including the need to examine the effects of multiple and more consistent doses and to study different mechanisms of action.