Distantly-Supervised Named Entity Recognition with Adaptive Teacher Learning and Fine-grained Student Ensemble

Distantly-Supervised Named Entity Recognition (DS-NER) effectively alleviates the data scarcity problem in NER by automatically generating training samples. Unfortunately, the distant supervision may induce noisy labels, thus undermining the robustness of the learned models and restricting the practical application. To relieve this problem, recent works adopt self-training teacher-student frameworks to gradually refine the training labels and improve the generalization ability of NER models. However, we argue that the performance of the current self-training frameworks for DS-NER is severely underestimated by their plain designs, including both inadequate student learning and coarse-grained teacher updating. Therefore, in this paper, we make the first attempt to alleviate these issues by proposing: (1) adaptive teacher learning comprised of joint training of two teacher-student networks and considering both consistent and inconsistent predictions between two teachers, thus promoting comprehensive student learning. (2) fine-grained student ensemble that updates each fragment of the teacher model with a temporal moving average of the corresponding fragment of the student, which enhances consistent predictions on each model fragment against noise. To verify the effectiveness of our proposed method, we conduct experiments on four DS-NER datasets. The experimental results demonstrate that our method significantly surpasses previous SOTA methods.Comment: Accepted at AAAI 202

Multiple genetic analyses to investigate the polymorphisms of Chinese Mongolian population with an efficient short tandem repeat panel

Aim To determine allele frequencies and forensic statistics of 22 autosomal short tandem repeat loci in Chinese Mongolian population. Methods Blood specimens were collected from 134 unrelated healthy Mongolian individuals, and 22 short tandem repeat loci were co-amplified and genotyped. Allele frequencies and forensic parameters were calculated, and population genetic differences were analyzed among Mongolian population and other eight Chinese populations: Northern Han, Guangdong Han, Chengdu Han, Xinjiang Hui, Xinjiang Uygur, Hainan Li, Qinghai Tibetan, and Hainan Han. Results All the loci were in the Hardy-Weinberg equilibrium, and after Bonferroni correction there was no linkage disequilibrium between them. The allele frequencies of these 22 loci were between 0.0037 and 0.3657. This panel had high discriminating power and genetic polymorphism in the Mongolian population, with combined power of discrimination of 0.999999999999999999999999998399 and combined probability of exclusion of 0.9999999999566925. Structure analysis showed no evidence that these nine Chinese populations had different component distribution. However, genetic distance analysis showed significant differences among them (P < 0.05). Conclusion The combined application of these 22 loci could be useful for forensic purposes in the Mongolian population. Mongolian population had smaller genetic distances from the populations in northern China (Northern Han, Xinjiang Uygur, and Xinjiang Hui) than from the populations in Hainan province (Hainan Han and Hainan Li populations)

Degradation and mechanism of 2,4-dichlorophenoxyacetic acid (2,4-D) by thermally activated persulfate oxidation

The chlorinated phenoxy herbicide of 2,4-dichlorophenoxyacetic acid (2,4-D) was oxidized by thermally activated persulfate (TAP). This herbicide was studied for different persulfate dosages (0.97–7.29 g L−1), for varying initial pH levels (3–12) and temperatures (25–70 °C). Compared with Fe2+/PS, TAP could achieve a higher total organic carbon (TOC) removal under wider pH ranges of 3–12. Increasing the mole ratio of PS to 2,4-D favored for the decay of 2,4-D and the best performance was achieved at the ratio of 50. The 2,4-D degradation rate constant highly depended on the initial pH and temperature, in accordance with the Arrhenius model, with an apparent activation energy of 135.24 kJ mol−1. The study of scavenging radicals and the EPR confirmed the presence of both SO4− and OH. However, SO4− was the predominant oxidation radical for 2,4-D decay. The presence of both Cl− and CO32− inhibited the degradation of 2,4-D, whereas the effect of NO3− could be negligible. Verified by GC/MS, HPLC and ion chromatography, a possible degradation mechanism was propose

Characteristics of convective storm activity during the warm season over Anhui Province based on radar mosaic climatology and the possible causes

In order to understand the radar climatology characteristics of convective activity over Anhui Province, the climatological distribution and influencing factors of convective activity during the warm season (May-September) were investigated using Doppler radar mosaic data from five Next Generation Weather Radars and ERA5 reanalysis data between 2015 and 2020. Results indicate that: (1) There are obvious inter-monthly variations and spatial differences of convective activity during the warm season. The convective activity peaks during the Meiyu period, with the highest frequency in June and July, followed by May and August, and the lowest in September. The region with the highest convective in July and July is mainly distributed in the southwest-northeast direction. (2) It is found that the diurnal variation of convective number is bimodally distributed in summer (June-August), with the main peak in the afternoon and a subpeak in the early morning. In June, the peak convective activity mainly occurs in the early morning, which is related to the strengthening of low-level southwest airflow from night to early morning, and thus enhancing the moisture flux convergence in Anhui. In July, the peak convective activity appears in the afternoon, with a subpeak in the early morning. Note that the main peak is stronger and the duration is longer, which is related to the enhancement of convective available potential energy in Anhui in July. The second peak in early morning is also caused by the strengthening of the low-level southwest airflow, which is similar to that in June, but the intensity is weaker. Convective activity in August exhibits a single peak in the afternoon with the most significant diurnal variation, which shows a typical afternoon thermal convection type

Clinical Efficacy and Safety Comparison of Rivaroxaban and Dabigatran for Nonvalvular Atrial Fibrillation Patients Undergoing Percutaneous Left Atrial Appendage Closure Operation

Objective: Due to the clinical complexity of warfarin, novel oral anticoagulation (NOAC) has been a feasible and safe alternative anticoagulant approach during left atrial appendage closure (LAAC). This study was designed to compare the efficacy and safety of rivaroxaban and dabigatran for nonvalvular atrial fibrillation patients undergoing percutaneous LAAC.Methods: One single and prospective cohort study was performed among patients who received anticoagulation with dabigatran or rivaroxaban. All patients were medicated with a 3-month course of NOAC to facilitate device endothelialization, followed by dual antiplatelet therapy until 6 months, then lifelong aspirin after discharge. Repeated transesophageal echocardiography was scheduled to evaluate thrombosis formation on occluders and thrombus dissolution ability.Results: A total of 262 consecutive patients were initially enrolled. A final number of 250 patients were analyzed; two patients were excluded due to procedure failure and 10 patients had a loss of follow-up; 97 were from the dabigatran group and 153 from the rivaroxaban group. Three patients (1.9%) in the rivaroxaban group and eight (8.2%) in the dabigatran group were experiencing device-related thrombosis (DRT) events during follow-ups. Cumulative Kaplan–Meier estimates showed that the incidence of DRT was lower under rivaroxaban medication during the 6-month follow-ups (p = 0.038*, OR = 3.843, 95%CI: 0.991–14.836). The transesophageal echocardiography (TEE) results showed that the average length and width of DRT in the rivaroxaban group was significantly lower compared with that in the dabigatran group (2.16 vs. 1.60 mm, p = 0.017*, and 1.71 vs. 1.30 mm, p = 0.003*, respectively). The thrombosis dissolved after the switch from dabigatran or rivaroxaban to warfarin within the target range, represented by the average length and width of thrombus with the cooperation of secondary TEE for the dabigatran and rivaroxaban groups (0.64 vs. 0.40 mm, p = 0.206, and 0.43 vs. 0.27 mm, p = 0.082, respectively). No significant difference was found between the two groups with respect to the levels of coagulation parameters, cardiac function, and bleeding events.Conclusion: Compared to dabigatran, post-procedural rivaroxaban anticoagulation might be advantageous in preventing DRT complications expected after LAAC, without increasing the risk of hemorrhage

A Novel W-Band Dual-Polarized Cassegrain Antenna for Cloud Radar

Abstract-A W-band dual-polarized Cassegrain antenna for cloud radar is proposed. The aperture diameter of the main reflector of the antenna is 50 cm. By using a modified Magic-T structure in the feed horn, the antenna is dual-polarized with high port isolation. The measured results show that the port isolation is 44.7 dB. The gains are 47.3 dB and 49.5 dB for the two ports at 94 GHz, respectively, and the efficiency of the antenna is better than 87%

Population Genetic Diversity and Clustering Analysis for Chinese Dongxiang Group With 30 Autosomal InDel Loci Simultaneously Analyzed

In comparison with the most preferred genetic marker utilized in forensic science (STR), insertion/deletion analysis possesses further benefits, like absence of stutter peak, low mutation rate, and enabling mixed stain analysis. At present, a total of 169 unrelated healthy Dongxiang individuals dwelling in Dongxiang Autonomous county of Gansu province were recruited in our study to appraise the forensic usefulness of the panel including 30 autosomal diallelic genetic markers. The insertion allele frequencies were in the range of 0.1598 at HLD 111 to 0.8550 at HLD 118. The cumulative match of probability and the combined probability of exclusion were estimated based on independence of pairwise loci, with the values of 3.96 × 10-11 and 0.9886, respectively, which showed tremendous potential of this panel to be qualified for forensic personal identification in Chinese Dongxiang group. And it could also be used as a complementary tool for forensic parentage testing when combined with standard STR genetic markers. Furthermore, calculation of the DA distance and Fst values of pairwise populations, phylogenetic reconstruction, multidimensional scaling analysis, structure clustering analysis were also conducted to probe the genetic relationships between Dongxiang group and the other 30 reference populations. Results demonstrated that Dongxiang ethnic group might be genetically closer related with most Chinese populations involved in our study, especially Tibet groups, Xibe group, and several Han populations