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  1. Curcumin is a derivative of the turmeric spice, which is a yellow-pigmented root crop with a resilient sheath and bright orange flesh. It is originally known to be utilized in Asian dishes but, has been discovered to have antioxidant, anti-inflammatory, antiviral, antibacterial and anticancer characteristics. Different researchers have established great possibilities of curcumin's ability to prohibit the growth of cancer cells especially, because of its potentiality to differentiate between normal and cancerous cells. Research questions include understanding the effects of curcumin on the MCF-7 breast cancer cells with regards to the biomolecules of the cells. The results indicated that after attachment of cells for 48 hours, the concentration of curcumin at 15 µM showed more than 90% inhibition of cells within 24 hours. The analysis was carried out on the viability of the cells, western blotting and reverse transcriptase-polymerase chain reaction. Western blot analysis of signaling proteins from curcumin-treated cells showed that the expression level of phosphorylated protein p44/42 in the MAP kinase pathway was significantly decreased and the apoptotic marker cleaved caspase 3 was increased as compared to the curcumin-untreated control cells. Moreover, RT-PCR analysis of the reference genes in the apoptotic pathway (p53, caspase 9, BCL-2 and Bax) demonstrated the upregulation of p53, Bax and caspase 9 genes. The results assembled from this present study suggested that curcumin inhibited the growth and induced caspase-mediated apoptosis of MCF-7 cells via the MAPK signaling pathway. Therefore, breast cancer treatment with curcumin seems to be a promising remedial path in near future. 
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  2. Nanoparticles have been widely used as remedies for disorders for a long time. They are 10-9 m specks of substances that can be found both naturally and synthesized in the laboratory with metal and nonmetal materials. In this study, gold nanoparticles (AuNPs) were synthesized using the citrate reduction method, and the 35 nm size of the nanoparticles was determined using a UV-Vis Spectrophotometer at 525 nm wavelength. The synthesized nanoparticles were further studied on MCF-7 breast cancer cells to understand how various genes are expressed in the induction of apoptosis in signal transduction pathways. The results obtained from the anticancer activity of the gold nanoparticles showed approximately 90% inhibition of cell growth after 72 hours of treatment. Western blot analysis demonstrated the downregulation of p44/42 MAPK (ERK1/2) protein due to gold nanoparticle treatment. Moreover, reverse transcription-polymerase chain reaction (RT-PCR) analysis of apoptotic genes revealed the upregulation of the p53 tumor suppressor gene, Bax, and caspase-9. The results assembled from this study further indicates that p44/42 MAPK, p53, caspase 9 and Bax play a major role in the mechanism of apoptosis in the MCF-7 breast cancer cells. 
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  3. Abstract

    We formulate an expression for the turbulent kinetic energy dissipation rate,ϵ, associated with shear‐generated turbulence in terms of quantities in the ocean or atmosphere that, depending on the situation, may be measurable or resolved in models. The expression depends on the turbulent vertical length scale,v, the inverse time scaleN, and the Richardson numberRi = N2/S2, whereSis the vertical shear, withvscaled in a way consistent with theories and observations of stratified turbulence. Unlike previous studies, the focus is not so much on the functional form ofRi, but the vertical variation of the length scalev. Using data from two ∼7‐day time series in the western equatorial Pacific, the scaling is compared with the observedϵ. The scaling works well with the estimatedϵcapturing the differences in amplitude and vertical distribution of the observedϵbetween the two times series. Much of those differences are attributable to changes in the vertical distribution of the length scalev, and in particular the associated turbulent velocity scale,ut. We relateutto a measure of the fine‐scale variations in velocity,. Our study highlights the need to consider the length scale and its estimation in environmental flows. The implications for the vertical variation of the associated turbulent diffusivity are discussed.

     
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  4. Abstract

    Aging, often considered a result of random cellular damage, can be accurately estimated using DNA methylation profiles, the foundation of pan-tissue epigenetic clocks. Here, we demonstrate the development of universal pan-mammalian clocks, using 11,754 methylation arrays from our Mammalian Methylation Consortium, which encompass 59 tissue types across 185 mammalian species. These predictive models estimate mammalian tissue age with high accuracy (r > 0.96). Age deviations correlate with human mortality risk, mouse somatotropic axis mutations and caloric restriction. We identified specific cytosines with methylation levels that change with age across numerous species. These sites, highly enriched in polycomb repressive complex 2-binding locations, are near genes implicated in mammalian development, cancer, obesity and longevity. Our findings offer new evidence suggesting that aging is evolutionarily conserved and intertwined with developmental processes across all mammals.

     
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    Free, publicly-accessible full text available September 1, 2024
  5. null (Ed.)
    Continental rifting is fundamental for the formation of ocean basins, and active rift zones are dynamic regions of high geohazard potential. However, much of what we know from the fault to plate scale is poorly constrained and is not resolved at any level of spatial or temporal detail over a complete rift system. For International Ocean Discovery Program Expedition 381, we propose drilling within the active Corinth rift, Greece, where deformation rates are high, the synrift succession is preserved and accessible, and a dense, seismic database provides high-resolution imaging, with limited chronology, of the fault network and of seismic stratigraphy for the recent rift history. In Corinth, we can therefore achieve an unprecedented precision of timing and spatial complexity of rift-fault system development and rift-controlled drainage system evolution in the first 1–2 My of rift history. We propose to determine at a high temporal and spatial resolution how faults evolve, how strain is distributed, and how the landscape responds within the first few million years in a nonvolcanic continental rift, as modulated by Quaternary changes in sea level and climate. High horizontal spatial resolution (1–3 km) is provided by a dense grid of seismic profiles offshore that have been recently fully integrated and are complemented by extensive outcrops onshore. High temporal resolution (~20–50 ky) will be provided by seismic stratigraphy tied to new core and log data from three carefully located boreholes to sample the recent synrift sequence. Two primary themes are addressed by the proposed drilling integrated with the seismic database and onshore data. First, we will examine fault and rift evolutionary history (including fault growth, strain localization, and rift propagation) and deformation rates. The spatial scales and relative timing can already be determined within the seismic data offshore, and dating of drill core will provide the absolute timing offshore, the temporal correlation to the onshore data, and the ability to quantify strain rates. Second, we will study the response of drainage evolution and sediment supply to rift and fault evolution. Core data will define lithologies, depositional systems and paleoenvironment (including catchment paleoclimate), basin paleobathymetry, and relative sea level. Integrated with seismic data, onshore stratigraphy, and catchment data, we will investigate the relative roles and feedbacks between tectonics, climate, and eustasy in sediment flux and basin evolution. A multidisciplinary approach to core sampling integrated with log and seismic data will generate a Quaternary chronology for the synrift stratigraphy down to orbital timescale resolutions and will resolve the paleoenvironmental history of the basin in order to address our objectives. 
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  6. A model devised by Thorpe & Li ( J. Fluid Mech. , vol. 758, 2014, pp. 94–120) that predicts the conditions in which stationary turbulent hydraulic jumps can occur in the flow of a continuously stratified layer over a horizontal rigid bottom is applied to, and its results compared with, observations made at several locations in the ocean. The model identifies two positions in the Samoan Passage at which hydraulic jumps should occur and where changes in the structure of the flow are indeed observed. The model predicts the amplitude of changes and the observed mode 2 form of the transitions. The predicted dissipation of turbulent kinetic energy is also consistent with observations. One location provides a particularly well-defined example of a persistent hydraulic jump. It takes the form of a 390 m thick and 3.7 km long mixing layer with frequent density inversions separated from the seabed by some 200 m of relatively rapidly moving dense water, thus revealing the previously unknown structure of an internal hydraulic jump in the deep ocean. Predictions in the Red Sea Outflow in the Gulf of Aden are relatively uncertain. Available data, and the model predictions, do not provide strong support for the existence of hydraulic jumps. In the Mediterranean Outflow, however, both model and data indicate the presence of a hydraulic jump. 
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