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1.
Little is known about levels of awareness and perceptions of skin cancer among Africans living in Africa. This study assessed skin cancer awareness among 1271 deeply pigmented South Africans. Participants (n = 642 males vs n = 629 females) were aware of skin cancer (79%) with more females than males being aware of skin cancer (P = 0.02). Majority of all participants had never checked their skin for signs or symptoms of skin cancer (90%). Palms of hands and soles of feet were the least recognized anatomic sites for skin cancer development, despite these sites being the common sites for acral lentiginous melanoma in individuals with deeply pigmented skin. Results suggest a need for targeted skin cancer awareness among population groups with dark skin on identification, screening, and early detection, professional training for healthcare personnel and content on skin cancer in deeply pigmented skin in medical curricula.  相似文献   
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A three photon resonance arising due to coherent population trapped (CPT) states in multi-level systems, is experimentally shown to be a powerful spectral marker to detect interacting CPT states. In systems showing N type or double Λ type level configurations, these absorption resonances can be used to identify spectral positions of maximal interactions between competing CPT ground states. The contrast of the absorption resonance serves to identify even partially destructive interactions between the CPT states, eliminating the need for strong resonant changes of ground state coherence for identification. We demonstrate this effect in a room temperature, gaseous collection of 87Rb. atoms. Three laser fields interact with a double Λ configuration in the Zeeman degenerate levels of the ground state 5S1/2S_{1/2}, F = 1 and those of the excited states 5P3/2P_{3/2}, F = 0,1, around the D2 line. The three-photon resonance is studied in the counter-propagating third field when the other two co-propagating fields satisfy the two-photon resonance condition necessary for creation of CPT states. We envisage that this absorption feature in the third field, can become a veritable tool to quantify degradation of CPT induced effects in engineered quantum states using multi-level systems.  相似文献   
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Drug discovery continues to be one of the greatest contemporary challenges and rational application of modelling approaches is the first important step to obtain lead compounds, which can be optimised further. Virtual high throughput screening (VHTS) is one of the efficient approaches to obtain lead structures for a given target. Strategic application of different screening filters like pharmacophore mapping, shape-based, ligand-based, molecular similarity etc., in combination with other drug design protocols provide invaluable insights in lead identification and optimization. Screening of large databases using these computational methods provides potential lead compounds, thus triggering a meaningful interplay between computations and experiments. In this review, we present a critical account on the relevance of molecular modelling approaches in general, lead optimization and virtual screening methods in particular for new lead identification. The importance of developing reliable scoring functions for non-bonded interactions has been highlighted, as it is an extremely important measure for the reliability of scoring function. The lead optimization and new lead design has also been illustrated with examples. The importance of employing a combination of general and target specific screening protocols has also been highlighted.  相似文献   
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Let A be a nonempty finite subset of an additive abelian group G and let r and h be positive integers. The generalized h-fold sumset of A, denoted by \(h^{(r)}A\), is the set of all sums of h elements of A, where each element appears in a sum at most r times. The direct problem for \(h^{(r)}A\) is to find a lower bound for \(|h^{(r)}A|\) in terms of |A|. The inverse problem for \(h^{(r)}A\) is to determine the structure of the finite set A for which \(|h^{(r)}A|\) is minimal with respect to some fixed value of |A|. If \(G = \mathbb {Z}\), the direct and inverse problems are well studied. In case of \(G = \mathbb {Z}/p\mathbb {Z}\), p a prime, the direct problem has been studied very recently by Monopoli (J. Number Theory, 157 (2015) 271–279). In this paper, we express the generalized sumset \(h^{(r)}A\) in terms of the regular and restricted sumsets. As an application of this result, we give a new proof of the theorem of Monopoli and as the second application, we present new proofs of direct and inverse theorems for the case \(G = \mathbb {Z}\).  相似文献   
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This research deals with the inhibition activity of glutathione in 0.5 M HCl on the corrosion behavior of 6061Al-SiC(p) composite. Glutathione is an eco-friendly water-soluble inhibitor. Polarization results reveal the cathodic inhibitor behavior of glutathione (Gt). The inhibition performance of Gt increases by increasing its concentration and lowering the medium temperature. The decrease in the corrosion current density and increase in inhibition efficiency on increasing Gt concentration reveal the attenuation of composite corrosion. Experimental results indicate the mixed adsorption with predominantly physisorption of Gt molecules adsorption on the composite surface following Langmuir adsorption isotherm. The impedance measurements indicate the rise in polarization resistance with an increase in Gt concentration, showing the control of composite corrosion. The surface analysis of the corroded and inhibited composite samples using a scanning electron microscope and atomic force microscope supports Gt molecules’ adsorption. The quantum chemical calculations confirm the conclusions of the experimental studies.

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Background  

β-carotene 15,15'-monooxygenase (BCMO1) catalyzes the crucial first step in vitamin A biosynthesis in animals. We wished to explore the possibility that a carbocation intermediate is formed during the cleavage reaction of BCMO1, as is seen for many isoprenoid biosynthesis enzymes, and to determine which residues in the substrate binding cleft are necessary for catalytic and substrate binding activity. To test this hypothesis, we replaced substrate cleft aromatic and acidic residues by site-directed mutagenesis. Enzymatic activity was measured in vitro using His-tag purified proteins and in vivo in a β-carotene-accumulating E. coli system.  相似文献   
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In the Adriatic lagoons of northern Italy, manila clam (Ruditapes philippinarum) farming provides important socio-economic returns and local clams should be registered with the Protected Designations of Origin scheme. Therefore, there is a need for the development of rapid, cost-effective tests to guarantee the origin of the product and to prevent potential fraud. In this work, an elemental analysis (EA) coupled with isotope ratio mass spectrometry (IRMS) was employed to identify the isotopic fingerprints of clams directly collected onsite in three Adriatic lagoons and bought at a local supermarket, where they exhibited certification. In particular, a multivariate analysis of C/N, δ13C and δ15N in manila clam tissues as well as δ13C in shells and Δ13C (calculated as δ13Cshell–δ13Ctissues) seems a promising approach for tracking the geographical origin of manila clams at the regional scale.  相似文献   
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Iridin is a natural flavonoid found in Belamcanda chinensis documented for its broad spectrum of biological activities like antioxidant, antitumor, and antiproliferative effects. In the present study, we have investigated the antitumor potential of iridin in AGS gastric cancer cells. Iridin treatment decreases AGS cell growth and promotes G2/M phase cell cycle arrest by attenuating the expression of Cdc25C, CDK1, and Cyclin B1 proteins. Iridin-treatment also triggered apoptotic cell death in AGS cells, which was verified by cleaved Caspase-3 (Cl- Caspase-3) and poly ADP-ribose polymerase (PARP) protein expression. Further apoptotic cell death was confirmed by increased apoptotic cell death fraction shown in allophycocyanin (APC)/Annexin V and propidium iodide staining. Iridin also increased the expression of extrinsic apoptotic pathway proteins like Fas, FasL, and cleaved Caspase-8 in AGS cells. On the contrary, iridin-treated AGS cells did not show variations in proteins related to an intrinsic apoptotic pathway such as Bax and Bcl-xL. Besides, Iridin showed inhibition of PI3K/AKT signaling pathways by downregulation of (p-PI3K, p-AKT) proteins in AGS cells. In conclusion, these data suggest that iridin has anticancer potential by inhibiting PI3K/AKT pathway. It could be a basis for further drug design in gastric cancer treatment.  相似文献   
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