139 research outputs found
Dehydration drives damage in the freezing of brittle hydrogels
It is widely known that freezing breaks soft, wet materials. However, the
mechanism underlying this damage is still not clear. To understand this
process, we freeze model, brittle hydrogel samples, while observing the growth
of ice-filled cracks that break these apart. We show that damage is not caused
by the expansion of water upon freezing, or the growth of ice-filled cavities
in the hydrogel. Instead, local ice growth dehydrates the surrounding hydrogel,
leading to drying-induced fracture. This dehydration is driven by the process
of cryosuction, whereby undercooled ice sucks nearby water towards itself,
feeding its growth. Our results highlight the strong analogy between freezing
damage and desiccation cracking, which we anticipate being useful for
developing an understanding of both topics. Our results should also give useful
insights into a wide range of freezing processes, including cryopreservation,
food science and frost heave
Inhibition of the m6A reader IGF2BP2 as a strategy against T-cell acute lymphoblastic leukemia
T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignant leukemia with extremely limited treatment for relapsed patients. N6‐methyladenosine (m6A) reader insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) participates in the initiation and growth of cancers by communicating with various targets. Here, we found IGF2BP2 was highly expressed in T-ALL. Gain and loss of IGF2BP2 demonstrated IGF2BP2 was essential for T-ALL cell proliferation in vitro and loss of IGF2BP2 prolonged animal survival in a human T-ALL xenograft model. Mechanistically, IGF2BP2 directly bound to T-ALL oncogene NOTCH1 via an m6A dependent manner. Furthermore, we identified a small-molecule IGF2BP2 inhibitor JX5 and treatment of T-ALL with JX5 showed similar functions as knockdown of IGF2BP2. These findings not only shed light on the role of IGF2BP2 in T-ALL, but also provide an alternative γ‑Secretase inhibitors (GSI) therapy to treat T-ALL.Inhibition of the m6A reader IGF2BP2 as a strategy against T-cell acute lymphoblastic leukemiapublishedVersio
Correlation of lifestyle behaviors during pregnancy with postpartum depression status of puerpera in the rural areas of South China
BackgroundPostpartum depression (PPD) is among the most common postpartum complications. Its prevalence is associated with strong regional variability. Women in rural areas of China have a high risk of PPD. The aim of this study was to investigate the PPD status of women in rural South China and explore the effects of modifiable lifestyle behaviors during pregnancy on their PPD status, thereby providing a scientific basis for the prevention and intervention of PPD in rural China.MethodsA cohort study was conducted on 261 women from four maternal health institutions situated in rural areas of Guangdong Province and the Guangxi Zhuang Autonomous Region from October 2021 to December 2022. The questionnaires were administered to these women to obtain data about sociodemographic characteristics, health literacy, physical activity during pregnancy, and sleep and dietary status during pregnancy, as well as depression status on the 42nd day after delivery. The lifestyle behaviors during pregnancy and the PPD status of the study population were analyzed. Multiple linear regression models were used to determine the correlation between lifestyle behaviors and PPD status. Path analysis was performed to explore the interaction between various lifestyle behaviors.ResultsA total of 14.6% of women had a PPD status. Women who continued to work during pregnancy had an Edinburgh Postpartum Depression Scale (EPDS) score of 1.386 points higher than that of women who did not (В = 1.386, β = 0.141, p = 0.029). For every 1-point increase in the infant feeding-related knowledge score and pregnancy diet diversity score, the EPDS score decreased by 0.188 and 0.484 points, respectively, and for every 1-point increase in the Pittsburgh sleep quality index score, the EPDS score increased by 0.288 points. Age was related to infant feeding-related knowledge (indirect path coefficient = 0.023). During pregnancy, sedentary time was correlated with sleep quality (indirect path coefficient = 0.031) and employment status (indirect path coefficient = 0.043).ConclusionEmployment status, infant feeding-related knowledge, sleep quality, and diet diversity during pregnancy directly influenced the PPD status, while age and sedentary time during pregnancy indirectly influenced the PPD status. Promoting healthy lifestyle behaviors, including reducing sedentary time, improving sleep quality, and increasing dietary diversity, may be effective in reducing PPD occurrence
Ultra-broadband Light Absorption by a Sawtooth Anisotropic Metamaterial Slab
We present an ultra broadband thin-film infrared absorber made of saw-toothed
anisotropic metamaterial. Absorbtivity of higher than 95% at normal incidence
is supported in a wide range of frequencies, where the full absorption width at
half maximum is about 86%. Such property is retained well at a very wide range
of incident angles too. Light of shorter wavelengths are harvested at upper
parts of the sawteeth of smaller widths, while light of longer wavelengths are
trapped at lower parts of larger tooth widths. This phenomenon is explained by
the slowlight modes in anisotropic metamaterial waveguide. Our study can be
applied in the field of designing photovoltaic devices and thermal emitters.Comment: 12 pages, 4 picture
Preparation and characterization of a novel composite microporous polymer electrolyte for Li-ion batteries
A novel composite microporous polymer electrolyte composed of poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) and mesoporous SBA-15 was prepared. The composite solid polymer electrolyte (CSPE) exhibits ionic conductivity as high as 0.30 mS-(cm-1) with a composition of SBA-15 : PVdF-HFP=3 : 8 at room temperature. Infrared transmission spectroscopic results suggested that the mechanism of micropore formation is similar to that of the phase inversion. X-ray diffraction (XRD) results demonstrated that the addition of SBA-15 inhibits the crystallization of PVdF-HFP, while the SBA-15 preserves well its ordered mesoporous structure during the course of preparation. The Li/CSPE/MCF of half-cell was assembled, and it showed a good electrochemical and cyclability performance during charge-discharge cycles
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