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Cryogenic cave carbonates (CCCs) are a type of speleothem, typically dated with 230Th/U disequilibrium methods, that provide evidence of palaeo-permafrost conditions. In the field, CCCs occur as distinct patches of millimetre- to centimetre-sized loose crystals and crystal aggregates on the floors of cave chambers, so they lack a framework that would allow ages to be validated by stratigraphic order. Correction factors for the initial 230Th (230Th0) are often based on the bulk-earth-derived initial 230Th/232Th activity ratio ((230Th/232Th)0), which is a well-established approach when 230Th0 is moderately low. For samples with elevated levels of 230Th0, however, accuracy can be improved by constraining (230Th/232Th)0 independently. Here, we combine detailed morphological observations from three CCC patches found in Water Icicle Close Cavern in the Peak District (UK) with 230Th/U analyses. We find that individual CCC crystals show a range of morphologies that arise from non-crystallographic branching in response to the chemical evolution of the freezing solution. Results of 230Th/U dating indicate that samples with a large surface area relative to the sample volume are systematically more affected by contamination with 230Th0. By fitting isochrons to these results, we test whether the CCCs in a patch formed during the same freezing event, and demonstrate that (230Th/232Th)0 can deviate substantially from the bulk-earth-derived value and can also vary between the different CCC patches. Where CCCs display elevated 230Th0, isochrons are a useful tool to constrain (230Th/232Th)0 and obtain ages with improved accuracy. Detritus absorbed to the crystal surface is shown to be the most likely source of 230Th0. Our results suggest that some previously published CCC ages may merit re-assessment, and we provide suggestions on how to approach future dating efforts.

As an important equipment of power system, the insulator's normal operation is the basis to ensure the safe operation of the power system. The insulator positioning and identification technology based on machine vision can quickly and accurately complete the inspection of insulators on site and effectively save the cost of operation and maintenance. This paper proposes an insulator inspection method based on region‐convolutional neural networks (RCNNs). First, the dataset of the insulator image is preprocessed by means of data expansion. Then, the feature extraction of the insulator image is realised by using the zeiler fergus (ZF) network. The k‐means clustering method is used to optimise the selection of anchor points. Meanwhile, the non‐maximum suppression post‐processing algorithm is improved, and a non‐linear penalty factor is introduced to adapt to multi‐scale and overlapping occlusion insulator inspection. Experimental results show that the improved faster RCNNs insulator inspection method can accurately obtain the coordinate frame and the corresponding probability value of the insulator object and improve the average precision by 10.43%, achieving the accurate inspection of the insulator object.

Infantile hemangioma (IH) is one of the most common soft-tissue neoplasms of infancy. Although clinical diagnosis for IH is well-established, the haematological parameters associated with IH are not well explored. In this short study, we observed significantly higher eosinophil (EO) numbers in IH patient blood compared to healthy controls. This contributed to the observed higher EO % in the peripheral blood of IH patients and was irrespective of age. This new haematological finding could carry a potential diagnostic/prognostic relevance for IH.

miRNAs are involved in breast cancer initiation and progression. In this study, we investigated the role of miR-1193, a newly found and poorly studied miRNA, in the proliferation and invasion of human breast cancer cells. Our results showed that compared with the adjacent tissues and MCF-10A human normal breast cells, miR-1193 was sharply reduced in breast cancer tissues and five breast cancer cell lines, including MDA-MB-231, MDA-MB-468, MDA-MB-435, SKBR3, and MCF-7. The oligo miR-1193 mimic or anta-miR-1193 was then transfected into MDA-MB-231 and MCF-7 breast cancer cell lines. Our results showed that the miR-1193 mimic robustly increased the miR-1193 level and decreased the proliferation and invasion in MDA-MB-231 and MCF-7 cells. In contrast, anta-miR-1193 had an opposite effect on miR-1193 expression, cell proliferation, and cell invasion. Moreover, bioinformatic and luciferase reporter gene assays confirmed that miR-1193 targeted the mRNA 3′-UTR region of insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2), an identified proto-oncogene. miR-1193 suppressed the protein level of IGF2BP2 and the activation of the ERK and PI3K/Akt signaling pathways. Moreover, suppression could be rescued by the transfection of pcDNA-IGF2BP2. In conclusion, miR-1193 suppressed proliferation and invasion of human breast cancer cells via translational suppression of IGF2BP2.

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