TransNet: Transparent Object Manipulation Through Category-Level Pose Estimation

Transparent objects present multiple distinct challenges to visual perception systems. First, their lack of distinguishing visual features makes transparent objects harder to detect and localize than opaque objects. Even humans find certain transparent surfaces with little specular reflection or refraction, like glass doors, difficult to perceive. A second challenge is that depth sensors typically used for opaque object perception cannot obtain accurate depth measurements on transparent surfaces due to their unique reflective properties. Stemming from these challenges, we observe that transparent object instances within the same category, such as cups, look more similar to each other than to ordinary opaque objects of that same category. Given this observation, the present paper explores the possibility of category-level transparent object pose estimation rather than instance-level pose estimation. We propose \textit{\textbf{TransNet}}, a two-stage pipeline that estimates category-level transparent object pose using localized depth completion and surface normal estimation. TransNet is evaluated in terms of pose estimation accuracy on a large-scale transparent object dataset and compared to a state-of-the-art category-level pose estimation approach. Results from this comparison demonstrate that TransNet achieves improved pose estimation accuracy on transparent objects. Moreover, we use TransNet to build an autonomous transparent object manipulation system for robotic pick-and-place and pouring tasks

Terahertz Probing Irreversible Phase Transitions Related to Polar Clusters in Bi0.5Na0.5TiO3-based Ferroelectric

Electric-field-induced phase transitions in Bi0.5Na0.5TiO3 (BNT)-based relaxor ferroelectrics are essential to the controlling of their electrical properties and consequently in revolutionizing their dielectric and piezoelectric applications. However, the fundamental understanding of these transitions is a long-standing challenge due to their complex crystal structures. Given the structural inhomogeneity at the nanoscale or sub-nanoscale in these materials, dielectric response characterization based on terahertz (THz) electromagnetic-probe beam-fields, is intrinsically coordinated to lattice dynamics during DC-biased poling cycles. The complex permittivity reveals the field-induced phase transitions to be irreversible. This profoundly counters the claim of reversibility, the conventional support for which, is based upon the peak that is manifest in each of four quadrants of the current-field curves. The mechanism of this irreversibility is solely attributed to polar clusters in the transformed lattices. These represent an extrinsic factor which is quiescent in the THz spectral domain

Study on the work of new food additive safety evaluation in China

Objective Summarize and analyze the common issues on new food additive applications, and make suggestions on both processes of submission and evaluation of applications for new food additives, and facilitate scientific, reasonable and standardized evaluation. Methods Use the "health administrative authorization management system" to obtain the statistics of new food additives applied in the year of 2010-2019, analyze the common problems, and put forward suggestions from technical aspects for new food additives. Results By analyzing final decisions of 769 new food additives applied in 2010-2019, common problems in both reception and safety evaluation stage were pointed out. On this basis, suggestions were put forward to further improve dossier requirements and safety data requirements from the management perspective. Conclusion The existing new food additive regulations and requirements can basically meet the needs of the safety evaluation. It is suggested to further refine the application requirements, formulate the application guidelines, and reinforce the safety evaluation requirements of new food additives

Research and analysis on feedback from national food safety special follow-up evaluation

Objective To obtain the comprehensive evaluation from stakeholders by carrying out special follow-up evaluation on national food safety standards, so as to provide reference for further improvement of China's national food safety standards system. Methods Questionnaire was designed, and the opinions of stakeholders were collected through National Food Safety Standards Follow-up Evaluation and Feedback Platform. Excel 2013 was used to sort out the original data and make descriptive statistical analysis. Results The analysis of 5 467 questionnaires showed that more than 90% of the respondents thought that the food classification in the current national food safety general standards was clear and the limits were scientific and reasonable. The food products could be covered by the corresponding food safety standards and code of practice standards. The comprehensive score of food safety product standards was 4.37 (out of 5), and the comprehensive score of code of practice standards was 4.42 (out of 5). Conclusion China’s current food safety standards system framework is basically perfect, and the convergence between standards is smooth. The coverage rate of general standards, product standards and code of practice standards for all kinds of food products exceeds 90%, and the system setting is reasonable and perfect. It is suggested to further improve the national food safety standard system, make full use of the result of food safety standard follow-up evaluation, and continue to actively explore follow-up evaluation method to be brought in line with international practice

Thirty-six months recurrence after acute ischemic stroke among patients with comorbid type 2 diabetes: A nested case-control study

Background: Stroke patients have to face a high risk of recurrence, especially for those with comorbid T2DM, which usually lead to much more serious neurologic damage and an increased likelihood of death. This study aimed to explore determinants of stroke relapse among patients with comorbid T2DM. Materials and methods: We conducted this case-control study nested a prospective cohort of ischemic stroke (IS) with comorbid T2DM. During 36-month follow-up, the second stroke occurred in 84 diabetic IS patients who were allocated into the case group, while 613 patients without recurrence were the controls. We collected the demographic data, behaviors and habits, therapies, and family history at baseline, and measured the variables during follow-up. LASSO and Logistic regression analyses were carried out to develop a prediction model of stroke recurrence. The receiver operator characteristic (ROC) curve was employed to evaluate the performance of the prediction model. Results: Compared to participants without recurrence, the higher levels of pulse rate (78.29 ± 12.79 vs. 74.88 ± 10.93) and hypertension (72.6 vs. 61.2 %) were recorded at baseline. Moreover, a lower level of physical activity (77.4 vs. 90.4 %), as well as a higher proportion of hypoglycemic therapy (36.9 vs. 23.3 %) was also observed during 36-month follow-up. Multivariate logistic regression revealed that higher pulse rate at admission (OR = 1.027, 95 % CI = 1.005 – 1.049), lacking physical activity (OR = 2.838, 9 5 % CI = 1.418 – 5.620) and not receiving hypoglycemic therapy (OR = 1.697, 95 % CI = 1.013 – 2.843) during follow-up increased the risk of stroke recurrence. We developed a prediction model using baseline pulse rate, hypoglycemic therapy, and physical activity, which produced an area under ROC curve (AUC) of 0.689. Conclusion: Physical activity and hypoglycemic therapy play a protective role for IS patients with comorbid diabetes. In addition to targeted therapeutics, the improvement of daily-life habit contributes to slowing the progress of the IS

Perovskite Srx(Bi1-xNa0.97-xLi0.03)0.5TiO3 ceramics with polar nano regions for high power energy storage

Dielectric capacitors are very attractive for high power energy storage. However, the low energy density of these capacitors, which is mainly limited by the dielectric materials, is still the bottleneck for their applications. In this work, lead-free single-phase perovskite Srx(Bi1-xNa0.97-xLi0.03)0.5TiO3 (x=0.30 and 0.38) bulk ceramics, prepared using solid-state reaction method, were carefully studied for the dielectric capacitor application. Polar nano regions (PNRs) were created in this material using co-substitution at A-site to enable relaxor behaviour with low remnant polarization (Pr) and high maximum polarization (Pmax). Moreover, Pmax was further increased due to reversible electric field induced phase transitions. Comprehensive structural and electrical studies were performed to confirm the PNRs and the reversible phase transitions. And finally a high energy density (1.70 J/cm3) with an excellent efficiency (87.2%) was achieved using the contribution of PNRs and field-induced transitions in this material, making it among the best performing lead-free dielectric ceramic bulk material for high energy storage

Crystal structure and electrical properties of textured Ba2Bi4Ti5O18 ceramics

Highly textured Ba2Bi4Ti5O18 ceramic was prepared by spark plasma sintering (SPS). X-ray diffraction of the ceramics revealed the coexistence of a major ferroelectric phase (Space group, SG: B2cb) and a minor paraelectric phase (SG: I4/mmm) at room temperature. A diffused phase transition was observed at around 240 °C. The evolution of the switching current peaks in the electric current vs. electric field (I-E) loops with increasing temperature was interpreted by the structural changes and temperature dependent polarisation reversal processes. The slim polarisation vs. electric field (P-E) loops, the extra switching current peaks in the I-E loops and the non-zero piezoelectric d33 coefficient indicate that Ba2Bi4Ti5O18 is a relaxor ferroelectric material. The recoverable energy density (0.41 ± 0.01 J/cm3) of Ba2Bi4Ti5O18 ceramics in the perpendicular direction to the SPS pressing direction is close to that of Pb(Mg1/3Nb2/3)O3-based ceramics. The obtained results suggest Ba2Bi4Ti5O18 ceramics might be promising for energy storage applications

Multiscale Understanding of Electric Polarization in Poly(vinylidene fluoride)-Based Ferroelectric Polymers

Poly(vinylidene fluoride) (PVDF) and PVDF-based copolymers with trifluoroethylene (PVDF-TrFE) have attracted considerable academic and industrial interest due to their ferroelectric properties, which are only presented in very few polymers. However, the underlying fundamentals of molecular ordering and induced polarizations are complex and not fully understood. Herein, PVDF, PVDF-TrFE and their blends, prepared using melt extrusion and hot pressing, have been selected to obtain controlled case studies with well-defined chain ordering and microstructures. Impedance analysis and terahertz time-domain spectroscopy are exploited to investigate electric polarization in PVDF-based polymers at different length scales. The extruded ferroelectric films show in-plane chain orientation and higher domain wall density compared to hot pressed films with randomly-distributed polymer chains, which favors the polarization at low frequencies (Hz to MHz), as concluded from the higher dielectric constants and more prominent high electric field polarization switching features. However, the domain walls cannot respond at high frequencies, which leads to lower dielectric constants in the extruded films at THz frequencies

Optimal Regimens and Cutoff Evaluation of Tildipirosin Against Pasteurella multocida

Pasteurella multocida (PM) can invade the upper respiratory tract of the body and cause death and high morbidity. Tildipirosin, a new 16-membered-ring macrolide antimicrobial, has been recommended for the treatment of respiratory diseases. The objective of this research was to improve the dose regimes of tildipirosin to PM for reducing the macrolides resistance development with the pharmacokinetic/pharmacodynamic (PK/PD) modeling approach and to establish an alternate cutoff for tildipirosin against PM. A single dose (4 mg/kg body weight) of tildipirosin was administered via intramuscular (i.m.) and intravenous (i.v.) injection to the pigs. The minimum inhibitory concentration (MIC) values of clinical isolates (112) were measured in the range of 0.0625–32 μg/ml, and the MIC50 and MIC90 values were 0.5 and 2 μg/ml, respectively. The MIC of the selected PM04 was 2 and 0.5 μg/ml in the tryptic soy broth (TSB) and serum, respectively. The main pharmacokinetic (PK) parameters including the area under the curve at 24 h (AUC24 h), AUC, terminal half-life (T1/2), the time to peak concentration (Tmax), peak concentration (Cmax), relative total systemic clearance (CLb), and the last mean residence time (MRTlast) were calculated to be 7.10, 7.94 μg∗h/ml, 24.02, NA h, NA μg/ml, 0.46 L/h∗kg, 8.06 h and 3.94, 6.79 μg∗h/ml, 44.04, 0.25 h, 0.98 μg/ml, 0.43 L/h∗kg, 22.85 h after i.v. and i.m. induction, respectively. Moreover, the bioavailability of i.m. route was 85.5%, and the unbinding of tildipirosin to serum protein was 78%. The parameters AUC24 h/MIC in serum for bacteriostatic, bactericidal, and elimination activities were calculated as 18.91, 29.13, and 34.03 h based on the inhibitory sigmoid Emax modeling. According to the Monte Carlo simulation, the optimum doses for bacteriostatic, bactericidal, and elimination activities were 6.10, 9.41, and 10.96 mg/kg for 50% target and 7.86, 12.17, and 14.57 mg/kg for 90% target, respectively. The epidemiological cutoff value (ECV) was calculated to be 4 μg/ml which could cover 95% wild-type clinical isolates distribution. The PK-PD cutoff (COPD) was analyzed to be 0.25 μg/ml in vitro for tildipirosin against PM based on the Monte Carlo simulation. Compared with these two cutoff values, the finial susceptible breakpoint was defined as 4 μg/ml. The data presented now provides the optimal regimens (12.17 mg/kg) and susceptible breakpoint (4 μg/ml) for clinical use, but these predicted data should be validated in the clinical practice