Unified Multimodal Model with Unlikelihood Training for Visual Dialog

The task of visual dialog requires a multimodal chatbot to answer sequential questions from humans about image content. Prior work performs the standard likelihood training for answer generation on the positive instances (involving correct answers). However, the likelihood objective often leads to frequent and dull outputs and fails to exploit the useful knowledge from negative instances (involving incorrect answers). In this paper, we propose a Unified Multimodal Model with UnLikelihood Training, named UniMM-UL, to tackle this problem. First, to improve visual dialog understanding and generation by multi-task learning, our model extends ViLBERT from only supporting answer discrimination to holding both answer discrimination and answer generation seamlessly by different attention masks. Specifically, in order to make the original discriminative model compatible with answer generation, we design novel generative attention masks to implement the autoregressive Masked Language Modeling (autoregressive MLM) task. And to attenuate the adverse effects of the likelihood objective, we exploit unlikelihood training on negative instances to make the model less likely to generate incorrect answers. Then, to utilize dense annotations, we adopt different fine-tuning methods for both generating and discriminating answers, rather than just for discriminating answers as in the prior work. Finally, on the VisDial dataset, our model achieves the best generative results (69.23 NDCG score). And our model also yields comparable discriminative results with the state-of-the-art in both single-model and ensemble settings (75.92 and 76.17 NDCG scores).Comment: Accepted by the 30th ACM International Conference on Multimedia (ACM MM 2022

One-step hydrothermal synthesis of fluorescence carbon quantum dots with high product yield and quantum yield

A one-step hydrothermal synthesis of nitrogen and silicon co-doped fluorescence carbon quantum dots (N,Si-CQDs), from citric acid monohydrate and silane coupling agent KH-792 with a high product yield (PY) of 52.56% and high quantum yield (QY) of 97.32%, was developed. This greatly improves both the PY and QY of CQDs and provides a new approach for a large-scale production of high-quality CQDs. Furthermore, N,Si-CQDs were employed as phosphors without dispersants to fabricate white light-emitting diodes (WLEDs) with the color coordinates at (0.29, 0.32). It is suggested that N,Si-CQDs have great potential as promising fluorescent materials to be applied in WLEDs.Peer reviewe

Pleural effusion adenosine deaminase: a candidate biomarker to discriminate between Gram-negative and Gram-positive bacterial infections of the pleural space

OBJECTIVES: Delay in the treatment of pleural infection may contribute to its high mortality. In this retrospective study, we aimed to evaluate the diagnostic accuracy of pleural adenosine deaminase in discrimination between Gram-negative and Gram-positive bacterial infections of the pleural space prior to selecting antibiotics. METHODS: A total of 76 patients were enrolled and grouped into subgroups according to Gram staining: 1) patients with Gram-negative bacterial infections, aged 53.2±18.6 years old, of whom 44.7% had empyemas and 2) patients with Gram-positive bacterial infections, aged 53.5±21.5 years old, of whom 63.1% had empyemas. The pleural effusion was sampled by thoracocentesis and then sent for adenosine deaminase testing, biochemical testing and microbiological culture. The Mann-Whitney U test was used to examine the differences in adenosine deaminase levels between the groups. Correlations between adenosine deaminase and specified variables were also quantified using Spearman’s correlation coefficient. Moreover, receiver operator characteristic analysis was performed to evaluate the diagnostic accuracy of pleural effusion adenosine deaminase. RESULTS: Mean pleural adenosine deaminase levels differed significantly between Gram-negative and Gram-positive bacterial infections of the pleural space (191.8±32.1 U/L vs 81.0±16.9 U/L,

Epileptic seizures in patients with glioma: A single centrebased study in China

Purpose: To elucidate the outcomes of treatment and epidemiology of epilepsy  related to glioma in a single center in Chinese patients.Methods: Prescription medicines usage and clinical data were collected from  medical records of 119 patients with gliomas between August 2009 and September 2015. Fisher’s exact and Chi square tests were used for analysis of seizure incidence differences as per WHO Grades, histology, location as well as tumour number, age and sex.Results: Preoperative seizures were noted in 33.8 % of glioma patients. After surgery, all the patients were given antiepileptic drugs (AEDs) prophylactically. Ten patients (8.4 %) developed seizures in the initial postoperative week, and 73 (61.3 %) patients at the last follow-up period. Overall, seizure incidence was 74.2 % in WHO Grade II, 68.4 % in Grade III, and 56.6 % in Grade IV glioma patients. Good seizure control and tolerance was demonstrated by levetiracetam.  Phenytoin/carbamazepine were poorly tolerated due to adverse events. AED  discontinuation was done in 54 patients and 14 patients developed seizures within 6 months and again needed AED.Conclusion: Effective prophylaxis of seizure and acceptable adverse event profile are to be considered significantly in AEDs selection. Lower cognitive impairment risk and renal excretion associated with newer AEDs make them better than older  therapeutic agents for epilepsy control in brain tumour patients.Keywords: Brain tumour, Epilepsy, Glioma, Seizures, Levetiracetam, Phenytoin, Carbamazepine,Epidemiolog

In Vitro

Chitosan/collagen composite nanofibrous scaffold has been greatly concerned in recent years for its favorable physicochemical properties which mimic the native extracellular matrix (ECM) both morphologically and chemically. In a previous study, we had successfully fabricated nanofibrous chitosan/collagen composite by electrospinning. In the present study, we further investigate the biocompatibility of such chitosan/collagen composite nanofiber to be used as scaffolds in vascular tissue engineering. The porcine iliac artery endothelial cells (PIECs) were employed for morphogenesis, attachment, proliferation, and phenotypic studies. Four characteristic EC markers, including two types of cell adhesion molecules, one proliferation molecule (PCNA), and one function molecule (p53), were studied by semiquantitative RT-PCR. Results showed that the chitosan/collagen composite nanofibrous scaffold could enhance the attachment, spreading, and proliferation of PIECs and preserve the EC phenotype. Our work provides profound proofs for the applicable potency of scaffolds made from chitosan/collagen composite nanofiber to be used in vascular tissue engineering

An improved Kriging surrogate model method with high robustness for electrical machine optimization

This article presents a highly robust optimization method for electrical machines, taking the uncertain tolerances of machine manufacturing into account. Different from the traditional multi-objective optimization methods based on Kriging surrogate model, two genetic algorithm (GA) models with disparate sampling principles are used here to release heavy computational burden and to improve prediction accuracy. One is adding the final optimization result of GA as the samples into the initial surrogate model, while the other one is adding the samples from the optimization process for the initial surrogate model. A 12-slot 14-pole interior permanent magnet synchronous machine (IPMSM) is used for the case study, and two GA models are compared. Furthermore, the proposed robust optimization method is compared with a deterministic optimization method to demonstrate its superiority, and its effectiveness is verified by prototype tests.</p

Natural anti-phytopathogenic fungi compound phenol, 2, 4-bis (1, 1-dimethylethyl) from Pseudomonas fluorescens TL-1

A strain was isolated from tobacco phylloplane and preliminarily identified as Pseudomonas fluorescens TL-1, which had the visible inhibition against ten plant pathogenic fungi, viz., Curvularia lunata, Bipolaris maydis, Valsa mali, Rhizoctonia solani, Colletotrichum gloeosporioides, Sclerotinia sclerotiorum, Botrytis cinerea, Alternaria alternate, Fusarium oxysporum and Verticillium dahlia in dual culture experiments. The ethyl acetate extract of nutrient broth seeded with Pseudomonas fluorescens TL-1 suspension was separated into fifty-nine fractions by the Sephadex LH-20 column and the antifungal activity of each fraction was tested with paper disc diffusion method against Curvularia lunata. The results showed that fraction 1 to 3 had the strongest inhibitory effects on Curvularia lunata. Furthermore, GC/MS analysis of the constituents of fraction 1 to 59 confirmed that phenol, 2, 4-bis (1, 1-dimethylethyl) was the active compound for the antifungal activity from Pseudomonas fluorescens TL-1

Influence of High Voltage Electrostatic Field (HVEF) on Vigour of Aged Rice (Oryza sativa L.) Seeds

The vigour restoration of aged rice seeds is of great significance in agriculture. This paper studied the biological effects of high voltage electrostatic field (HVEF) on aged rice seeds, including dry seeds and wet seeds soaked in sterile deionized water for 24 hours. The results showed that HVEF slightly affected the vigour of the aged dry rice seeds while the seed vigour and seedling growth of the aged wet rice seeds were significantly improved. The germination rate and germination potentiality also showed moderate improvement after exposure to HVEF with electric intensity less than t 450 kV&acirc;&euro;&cent;m-1. Compared to control, the vigour index of aged wet rice seeds was increased 31.96%. No significant effects of HVEF on dry aged rice seeds were found