The environmental effects of microplastics and microplastic derived dissolved organic matter in aquatic environments: A review.

Currently, microplastics (MPs) have ubiquitously distributed in different aquatic environments. Due to the unique physicochemical properties, MPs exhibit a variety of environmental effects with the coexisted contaminants. MPs can not only alter the migration of contaminants via vector effect, but also affect the transformation process and fate of contaminants via environmental persistent free radicals (EPFRs). The aging processes may enhance the interaction between MPs and co-existed contaminants. Thus, it is of great significance to review the aging mechanism of MPs and the influence of coexisted substances, the formation mechanism of EPFRs, environmental effects of MPs and relevant mechanism. Moreover, microplastic-derived dissolved organic matter (MP-DOM) may also influence the elemental biogeochemical cycles and the relevant environmental processes. However, the environmental implications of MP-DOM are rarely outlined. Finally, the knowledge gaps on environmental effects of MPs were proposed.

FCOS-LSC: A Novel Model for Green Fruit Detection in a Complex Orchard Environment.

To better address the difficulties in designing green fruit recognition techniques in machine vision systems, a new fruit detection model is proposed. This model is an optimization of the FCOS (full convolution one-stage object detection) algorithm, incorporating LSC (level scales, spaces, channels) attention blocks in the network structure, and named FCOS-LSC. The method achieves efficient recognition and localization of green fruit images affected by overlapping occlusions, lighting conditions, and capture angles. Specifically, the improved feature extraction network ResNet50 with added deformable convolution is used to fully extract green fruit feature information. The feature pyramid network (FPN) is employed to fully fuse low-level detail information and high-level semantic information in a cross-connected and top-down connected way. Next, the attention mechanisms are added to each of the 3 dimensions of scale, space (including the height and width of the feature map), and channel of the generated multiscale feature map to improve the feature perception capability of the network. Finally, the classification and regression subnetworks of the model are applied to predict the fruit category and bounding box. In the classification branch, a new positive and negative sample selection strategy is applied to better distinguish supervised signals by designing weights in the loss function to achieve more accurate fruit detection. The proposed FCOS-LSC model has 38.65M parameters, 38.72G floating point operations, and mean average precision of 63.0% and 75.2% for detecting green apples and green persimmons, respectively. In summary, FCOS-LSC outperforms the state-of-the-art models in terms of precision and complexity to meet the accurate and efficient requirements of green fruit recognition using intelligent agricultural equipment. Correspondingly, FCOS-LSC can be used to improve the robustness and generalization of the green fruit detection models.

[Clinicopathological Analysis of Children's Systemic EBV-Positive T-Cell Lymphoma].

OBJECTIVE: To explore the clinical and pathologic features as well as prognosis of systemic EBV-positive T-cell lymphoma in children. METHODS: The clinical data including clinical manifestation, pathologic changes and treatment in 16 patients with children's systemic EBV-positive T-cell lymphoma were analyzed retrospectively, and follow-up of patients were carried out. RESULTS: The 16 cases included 12 males and 4  females with median age of 3.3 years old. It was demonstrated that the clinical and pathological features of the children's systemic EBV-positive T-cell lymphoma were as followed fever, hepatosplenomegaly, cytopenia, lymphadenopathy, and hemophagocytosis in bone marrow or organ. Histologically, the structures of lymph node was normal, partially or completely destoryed. The paracortical zone was expanded with prominent infiltration of small to medium-sized atypical lymphocytes. The major immunophenotypic characteristics were as follows: (1) Almost all biopsies exhibited prominent T cell proliferation. (2) CD3 was expressed in 16 patients (100%, 16/16), CD4 in 5 patients (31.3%, 5/16)，CD5 in 13 patients (81.3%, 13/16)，CD7 was expressed in 11 patients (68.8%, 11/16)，CD8 in 15 patients (93.8%, 15/16)，CD4 and CD8 were expressed in 5 patients (31.3%, 5/16)，CD4 and CD8 double-negative in patients (6.3%, 1/16)，16 patients were CD56 negative (100%, 16/16). (3) TCR gene cloning rearrangement in 16 patients (93.8%, 15/16). (4) EBV-EBER was expressed in 16 patients (100%, 16/16). 11 out of 16 cases died, 1 cese failed to be followed up, 1 case relapsed，and 3 cases survived, reseptively. The media survival time was 4 months. CONCLUSION: Systemic EBV-positive T-cell lymphoma predominantly occurred in childhood and early teen-age, and lacks specific clinic features, usually combined with hemophagocytic syndrome. The confirmed diagnosis requires comprehensive analysis of clinical manifestation, pathomorphology, immunohistochemical detection, EBV-EBER insite hybridization, and TCR gene test. The overall prognosis of the disease is poor and the fatality rate is high.

[The changes of circulating follicular regulatory T cells and follicular T helper cells in children immune thrombocytopenia].

OBJECTIVE: To investigate the changes and roles of follicular regulatory T cells (Tfr) and follicular T helper cells (Tfh) in the pathogenesis of children immune thrombocytopenia (ITP). METHODS: 32 untreated ITP patients, as well as 20 healthy controls were enrolled in this study. The proportion of circulating Tfr and Tfh cells were determined by flow cytometry; real-time PCR was performed to detect the expression of transcription factors and regulatory factors of Bcl-6, c-Maf, Blimp-1 and PD-1 mRNA; ELISA was used to detect plasma concentration of IL-2, IL-6, IL-10 and IL-21. RESULTS: (1)The proportion of Tfh cells were significantly higher (P<0.05), while the Tfr cells and the ratio of tfr/Tfh cells in ITP patients were significantly lower than that in health controls (P<0.05); (2)Correlation analysis showed that the Tfr cells and the ratio of Tfr/Tfh were positively correlated with the platelet counts and negatively with the levels of PA-IgG, while the proportion of Tfh cells was positively correlated with the levels of PA-IgG and negatively with the platelet counts in peripheral blood; (3)Transcription levels of Bcl-6 and c-Maf mRNA in CD4(+) T lymphocytes cells were significantly elevated, the Blimp-1 mRNA in CD4(+) cells and PD-1 mRNA levels of Treg were lower in ITP patients in comparison with healthy controls; (4)The higher Plasma concentration of IL-21, and lower concentration of IL-2 were found in ITP patients. CONCLUSION: (1)The lower proportion of Tfr cells and higher proportion of Tfh cells, as well as the abnormal ratio of Tfr/Tfh might account for the decreased platelet counts to be further involved in the immunological pathogenesis of children ITP; (2)The changes of plasma cytokines IL-2, IL-21 in microenvironment and the over-expression of Bcl-6 mRNA, c-Maf mRNA and the lower-expression of Blimp-1 mRNA in CD4(+) T cells, and over-expression of PD-1 mRNA in Treg cells might be account for the abnormal ratios of Tfr/Tfh cells in ITP patients.