24 research outputs found
Boosting microscopic object detection via feature activation map guided poisson blending
Microscopic examination of visible components based on micrographs is the gold standard for testing in biomedical research and clinical diagnosis. The application of object detection technology in bioimages not only improves the efficiency of the analyst but also provides decision support to ensure the objectivity and consistency of diagnosis. However, the lack of large annotated datasets is a significant impediment in rapidly deploying object detection models for microscopic formed elements detection. Standard augmentation methods used in object detection are not appropriate because they are prone to destroy the original micro-morphological information to produce counterintuitive micrographs, which is not conducive to build the trust of analysts in the intelligent system. Here, we propose a feature activation map-guided boosting mechanism dedicated to microscopic object detection to improve data efficiency. Our results show that the boosting mechanism provides solid gains in the object detection model deployed for microscopic formed elements detection. After image augmentation, the mean Average Precision (mAP) of baseline and strong baseline of the Chinese herbal medicine micrograph dataset are increased by 16.3% and 5.8% respectively. Similarly, on the urine sediment dataset, the boosting mechanism resulted in an improvement of 8.0% and 2.6% in mAP of the baseline and strong baseline maps respectively. Moreover, the method shows strong generalizability and can be easily integrated into any main-stream object detection model. The performance enhancement is interpretable, making it more suitable for microscopic biomedical applications
Carbon benefits of wolfberry plantation on secondary saline land in Jingtai oasis, Gansu:A case study on application of the CBP model
The largest global source of anthropogenic CO2 emissions comes from the burning of fossil fuel and approximately 30% of total net emissions come from land use and land use change. Forestation and reforestation are regarded worldwide as effective options of sequestering carbon to mitigate climate change with relatively low costs compared with industrial greenhouse gas (GHG) emission reduction efforts. Cash trees with a steady augmentation in size are recognized as a multiple-beneficial solution to climate change in China. The reporting of C changes and GHG emissions for sustainable land management (SLM) practices such as afforestation is required for a variety of reasons, such as devising land management options and making policy. The Carbon Benefit Project (CBP) Simple Assessment Tool was employed to estimate changes in soil organic carbon (SOC) stocks and GHG emissions for wolfberry (Lycium barbarum L.) planting on secondary salinized land over a 10 year period (2004–2014) in the Jingtai oasis in Gansu with salinized barren land as baseline scenario. Results show that wolfberry plantation, an intensively managed ecosystem, served as a carbon sink with a large potential for climate change mitigation, a restorative practice for saline land and income stream generator for farmers in soil salinized regions in Gansu province. However, an increase in wolfberry production, driven by economic demands, would bring environmental pressures associated with the use of N fertilizer and irrigation. With an understanding of all of the components of an ecosystem and their interconnections using the Drivers-Pressures-State-Impact-Response (DPSIR) framework there comes a need for strategies to respond to them such as capacity building, judicious irrigation and institutional strengthening. Cost benefit analysis (CBA) suggests that wolfberry cultivation was economically profitable and socially beneficial and thus well-accepted locally in the context of carbon sequestration. This study has important implications for Gansu as it helps to understand the role cash trees can play in carbon emission reductions. Such information is necessary in devising management options for sustainable land management (SLM)
Local Resistance in Early Medieval Chinese Historiography and the Problem of Religious Overinterpretation
Official Chinese historiography is a treasure trove of information on local resistance to the centralised empire in early medieval China (third to sixth century). Sinologists specialised in the study of Chinese religions commonly reconstruct the religious history of the era by interpreting some of these data. In the process, however, the primary purpose of the historiography of local resistance is often overlooked, and historical interpretation easily becomes ‘overinterpretation’—that is, ‘fabricating false intensity’ and ‘seeing intensity everywhere’, as French historian Paul Veyne proposed to define the term. Focusing on a cluster of historical anecdotes collected in the standard histories of the four centuries under consideration, this study discusses the supposedly ‘religious’ nature of some of the data they contain
Atomically dispersed Ni-N-C catalyst derived from NiZn layered double hydroxides for efficient electrochemical CO2 reduction
Atomically dispersed catalytic metal sites anchored on N-doped carbon support catalysts (M-N-C) show great prospects for CO2 electroreduction. Here, single-layer NiZn layered double hydroxides (NiZn-LDHs) was used as a sacrificial assistant to fabricate single-Ni atom anchored on ultrathin porous carbon catalyst. NiZn-LDHs were exfoliated to single-layer by polyhydroxy compounds which took as the carbon resource in Ni-N-C, and single layer NiZn LDHs taking as the Ni resource could avoid the agglomeration of Ni atoms during calcining. The CO Faradaic efficiency (FECO) of the synthesized Ni-N-C catalyst exceeded 90% at −0.6 to −1.0 V and a FECO of 95.2% with a current density of 24 mA cm−2 at −0.9 V. This work not only provides a new method for preparing M-N-C catalysts, but also offers an effective and controllable strategy for large-scale production of high-performance single-atom catalysts.</p
A 3D rGO-supported NiFe2O4 heterostructure from sacrificial polymer-assisted exfoliation of NiFe-LDH for efficient oxygen evolution reaction
NiFe2O4 takes an attractive potential candidate for oxygen evolution reaction (OER) catalysts, however, its usual preparation based on high-temperature calcination limits exposure of catalytically active sites. Herein, we report a new and efficient strategy for preparing NiFe2O4 supported by three-dimensional graphene network (NFO/3DGN) electrocatalysts. Specifically, NiFe layered double hydroxide (NiFe LDH) was exfoliated to single layer by polylactic acid (PLA), single layer NiFe LDH was released when PLA was hydrolyzed, and PLA hydrolysate etched single layer NiFe LDH to NiFe2O4; Meanwhile, the lamellar graphene oxide was reduced to 3DGN, so that NiFe2O4 was loaded on 3DGN, which means the agglomeration of NiFe2O4 could be prevented and efficient electron transmission channels for NiFe2O4 could be provided due to 3DGN. The as-prepared NFO/3DGN-10 exhibited an excellent electrocatalytic activity and stability for OER in an alkaline solution (with a low overpotential of 272 ± 25 mV at 10 mA cm−2 with a Tafel slope of 64 mV dec−1). Based on theoretical calculations, the reaction energy barrier of NiFe2O4 on the speed determination step reduced significantly owing to 3DGN. These results indicate that this facile fabrication method is a promising route for developing high-performance catalysts based on mixed metal spinel oxides supported by 3DGN
Novel function of biguanides in inhibition of phospholipase D1 expression via a translational mechanism in cancer cells
Mechanically Strong, Thermally Healable, and Recyclable Epoxy Vitrimers Enabled by ZnAl-Layer Double Hydroxides
To meet the demand of sustainable development, epoxy vitrimers based on the dynamic transesterification reaction (DTER) have received considerable attention recently due to their reprocessability and repairability. However, they suffer from low mechanical strength and rely heavily on external catalysts to ensure their curing and repair. Herein, we report a facile design of a novel ZnAl-LDH-catalyzed epoxy vitrimer nanocomposite via introducing ZnAl-layered double metal hydroxide (ZnAl-LDH) nanosheets. Our results show that ZnAl-LDH can be well dispersed in the epoxy vitrimer. Notably, ZnAl-LDH has multifunctionality, which can simultaneously catalyze the curing reaction and enhance the mechanical strength and repairable efficiency of the resultant vitrimer. For instance, the peak curing temperature of epoxy vitrimer with 2 wt % ZnAl-LDH is 8 °C lower than that of an epoxy vitrimer under the same loading between Zn2+ of Zn(OAc)2, demonstrating a strong catalytic action. The tensile strength and Young’s modulus of ZnAl-LDH/epoxy resin (ER) increase from 18 and 156 MPa to 42 and 307 MPa, respectively, due to the reinforcing effect of ZnAl-LDH and the increased cross-linking density. The repairable efficiency of ZnAl-LDH/ER can reach 95% after repair at 200 °C for 1 h, which is mainly due to the abundant catalytic sites and large contact areas of the ZnAl-LDH lamella. Hence, this work offers an innovative and scalable strategy for creating epoxy vitrimers combining exceptional mechanical strength and high repairable efficiency, which holds great promise for many practical applications in the industry