Publications by authors named "Dai-jun Zhang"

Single-cell RNA sequencing (scRNA-Seq) technology has emerged as a powerful tool to investigate cellular heterogeneity within tissues, organs, and organisms. One fundamental question pertaining to single-cell gene expression data analysis revolves around the identification of cell types, which constitutes a critical step within the data processing workflow. However, existing methods for cell type identification through learning low-dimensional latent embeddings often overlook the intercellular structural relationships.

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Introduction: Pancreatic ductal adenocarcinoma (PDAC) is the most prevalent malignancy of the pancreas, and the incidence of this disease is approximately equivalent to the mortality rate. Immunotherapy has made a remarkable breakthrough in numerous cancers, while its efficacy in PDAC remains limited due to the immunosuppressive microenvironment. Immunotherapy efficacy is highly correlated with the abundance of immune cells, particularly cytotoxic T cells.

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With the development of research on the complex aetiology of many diseases, computational drug repositioning methodology has proven to be a shortcut to costly and inefficient traditional methods. Therefore, developing more promising computational methods is indispensable for finding new candidate diseases to treat with existing drugs. In this paper, a model integrating a new variant of message passing neural network and a novel-gated fusion mechanism called GLGMPNN is proposed for drug-disease association prediction.

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Single-cell RNA sequencing (scRNA-seq) technology is famous for providing a microscopic view to help capture cellular heterogeneity. This characteristic has advanced the field of genomics by enabling the delicate differentiation of cell types. However, the properties of single-cell datasets, such as high dropout events, noise, and high dimensionality, are still a research challenge in the single-cell field.

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To evaluate the effect of anaerobic ammonium oxidation (ANAMMOX) on benzene degradation under denitrification, a sequencing batch reactor (SBR) under denitrification synergized with ANAMMOX (SBR-DenAna) for benzene degradation was established by inoculating anaerobic ammonium-oxidizing bacteria (AnAOB) into a SBR under denitrification reactor (SBR-Den) for benzene degradation. The average rate of benzene degradation and the maximum first-order kinetic constant in SBR-DenAna were 2.34- and 1.

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A sequencing batch reactor (SBR) was conducted to perform nitrification process. The influence of long-term trace hydrazine (NH) addition (about 3 mg·L) on ammonium oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in nitrifying sludge was investigated. The result indicated that and were related to AOB, and Nitrobacter was related to NOB in nitrifying sludge with NH addition, respectively.

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Polyhydroxyalkanoate (PHA) is one of the most promising biopolymers with the advantages of biodegradable biocompatible and renewable. A glycerol-fed PHA-producing mixed culture was enriched in a feast-famine regime. The substrate versatility and PHA production capacity of the mixed culture were studied using acetate,propionate,butyric, glucose and lactate as substrate, respectively.

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Background: The ras genes play an important role in the development and progression of human tumours. Neutralizing Ras proteins in the cytoplasm could be an effective approach to blocking ras signalling. In this study, we prepared anti-p21Ras single chain fragment variable antibody (scFv) and investigated its immunoreactivity with human tumours.

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Activated sludge process is an important approach for industrial Polyhydroxyalkanoate ( PHA ) production. Off-line measurement with a time lag and complex analysis, is a common method for PHA, but is not suitable for the process control of PHA production. Based on a model for simultaneous storage and growth-soluble microbial products (SSAG-SMP), it is assumed that there is the linear relationship between the PHA synthesized and OUR or HPR, respectively.

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Floc size distribution (FSD) and fractal dimension are the important parameters for activated sludge. FSD of aerobic activated sludge during flocculation process was measured by a laser particle size analyzer, and the influence of velocity gradient, VSS/ SS, EPS content and Zeta potential on FSD was investigated. The results showed that the floc volume-average size was negatively correlated to velocity gradient (R > 0.

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The long-term addition of N2H4 to completely autotrophic nitrogen removal over nitrite (CANON) sequencing batch reactors (SBRs) recovered and enhanced their autotrophic nitrogen removal capacity while simultaneously reducing their production of NO3(-). The total nitrogen (TN) removal rate and TN removal efficiency of the process increased from 0.202±0.

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A set of automatically titrimetric system to monitor the hydrogen ion variation during biological wastewater treatment process in a batch bioreactor was developed, which consists of a batch bioreactor, data auto-acquisition and preservation unit, and titrant autodosing unit. The accuracy of measurement for the system was evaluated by measuring the stoichiometric ratio of hydrogen ion production amount to ammonium consumption amount of ammonium oxidation in an activated sludge system. The ratios measured in a 1L bioreactor with NH4+ -N concentrations of 1.

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Respirometry was made using wastewater and activated sludge from a WWTP of Chongqing through self-developed hybrid respirometer. And complete oxygen uptake rate (OUR) curves containing OUR of biodegradation process of RBCOD and SBCOD and endogenous process were obtained. A new method based on respirometry was proposed to characterize RBCOD and SBCOD in wastewater simultaneously, in which hydrolysis model was selected to analyze OUR curves of SBCOD according to the two-phases nature of exogenous OUR and trend-test method for endogens OUR.

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An expanded granular sludge bed (EGSB) reactor inoculated simultaneously with aerobic ammonium oxidation sludge and anaerobic ammonium oxidation sludge were start-up to enrich completely autotrophic nitrogen removal granular sludge. Total nitrogen (TN) removal rate reached 0.101 kg x (m3 x d)(-1).

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The effect of trace NO2 and kinetic characteristics for anaerobic ammonium oxidation of granular sludge was investigated by batch experiment. The sludge anammox rates could be described by the Haldane model. The kinetic parameters were determined, where the maximum anammox rate was 6.

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The anaerobic ammonium oxidation (ANAMMOX) activity of the sludge was about 9.84 x 10(-4) mg x (mg x h)(-1) by measuring the simultaneous consumption of ammonium and nitrite under anoxic conditions in the batch tests. The consumption of NO2(-) -N and NH4+ -N was 1.

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The kinetics of the NO2-dependent ammonia oxidation was developed for ammonia oxidizer mixed culture when there was no molecular oxygen in the batch tests. The kinetics parameters were determined, where the half saturate coefficient of NO2 was 0.821 micromol x L(-1), inhibition coefficient of NO2 concentration was 1.

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