61 research outputs found

    Role of the extracellular matrix proteins in the resistance of SP6.5 uveal melanoma cells toward cisplatin

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    Uveal melanoma is the most frequent primary intraocular tumor in the adult population. This malignancy has a high mortality rate and responds poorly to existing chemotherapy. Recently, the tumor environment has been found to exert a profound influence on drug response through cell interaction with components from the extracellular matrix (ECM). In the present study, we investigated whether individual components from the ECM may affect cell survival and/or cell death induced by the cytotoxic agent cisplatin on the SP6.5 uveal melanoma cell line. Tumor cells were shown by immunofluorescence analyses to be surrounded by the ECM proteins fibronectin (FN), type IV collagen (CIV) and laminin (LM), both at the primary and metastatic sites. Binding of SP6.5 cells to FN, LM and CIV is primarily dictated by the expression of membrane bound integrins from the beta1 family as revealed by cell adhesion assays conducted on ECM-coated culture plates. Analysis of cell death by flow cytometry demonstrated that culturing SP6.5 cells in the presence of FN, CIV and LM, substantially reduced the percentage of cells undergoing apoptosis after cisplatin treatment when compared with those seeded on a non-permissive matrix. These results suggest that adhesion of the SP6.5 uveal melanoma cells to the ECM proteins FN, CIV and LM might therefore confer resistance to the chemotherapeutic agent cisplatin. The cellular resistance induced by the ECM proteins toward cisplatin could explain in part the local recurrence of metastasis derived from uveal melanoma often observed clinically after chemotherapy

    Colloquium: Light scattering by particle and hole arrays

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    This colloquium analyzes the interaction of light with two-dimensional periodic arrays of particles and holes. The enhanced optical transmission observed in the latter and the presence of surface modes in patterned metal surfaces are thoroughly discussed. A review of the most significant discoveries in this area is presented first. A simple tutorial model is then formulated to capture the essential physics involved in these phenomena, while allowing analytical derivations that provide deeper insight. Comparison with more elaborated calculations is offered as well. Finally, hole arrays in plasmon-supporting metals are compared to perforated perfect conductors, thus assessing the role of plasmons in these types of structures through analytical considerations.Comment: 19 figure

    ĐœĐ”Ń‚ĐŸĐŽĐŸĐ»ĐŸĐłĐžŃ ŃĐžĐœŃ‚Đ”Đ·Đ° архОтДĐșтуры ĐżŃ€ĐŸĐłŃ€Đ°ĐŒĐŒĐœĐŸ-Ń‚Đ”Ń…ĐœĐžŃ‡Đ”ŃĐșĐŸĐłĐŸ ĐșĐŸĐŒĐżĐ»Đ”Đșса Đ°ĐČŃ‚ĐŸĐŒĐ°Ń‚ĐžĐ·ĐžŃ€ĐŸĐČĐ°ĐœĐœĐŸĐč ŃĐžŃŃ‚Đ”ĐŒŃ‹ ĐŒĐŸĐœĐžŃ‚ĐŸŃ€ĐžĐœĐłĐ° ĐŸĐ±ŃŃ‚Đ°ĐœĐŸĐČĐșĐž

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    ĐŸŃ€Đ”ĐŽĐ»ĐŸĐ¶Đ”Đœ ĐżĐŸĐŽŃ…ĐŸĐŽ Đș ĐżŃ€ĐŸĐ”ĐșŃ‚ĐžŃ€ĐŸĐČĐ°ĐœĐžŃŽ архОтДĐșтуры ĐżŃ€ĐŸĐłŃ€Đ°ĐŒĐŒĐœĐŸ-Ń‚Đ”Ń…ĐœĐžŃ‡Đ”ŃĐșĐŸĐłĐŸ ĐșĐŸĐŒĐżĐ»Đ”Đșса Đ°ĐČŃ‚ĐŸĐŒĐ°Ń‚ĐžĐ·ĐžŃ€ĐŸĐČĐ°ĐœĐœĐŸĐč ŃĐžŃŃ‚Đ”ĐŒŃ‹ ĐŒĐŸĐœĐžŃ‚ĐŸŃ€ĐžĐœĐłĐ° ĐŸĐ±ŃŃ‚Đ°ĐœĐŸĐČĐșĐž ĐČ Ń€Đ”Đ°Đ»ŃŒĐœĐŸĐŒ ĐČŃ€Đ”ĐŒĐ”ĐœĐž, ĐŸŃĐœĐŸĐČĐ°ĐœĐœŃ‹Đč ĐœĐ° ĐșлассОфОĐșацоо Ń€Đ”ŃˆĐ°Đ”ĐŒŃ‹Ń… Ń„ŃƒĐœĐșŃ†ĐžĐŸĐœĐ°Đ»ŃŒĐœŃ‹Ń… заЎач ĐœĐ° ĐŸŃĐœĐŸĐČĐ” ĐŒĐ”Ń‚ĐŸĐŽĐŸĐČ ĐșĐ»Đ°ŃŃ‚Đ”Ń€ĐœĐŸĐłĐŸ Đ°ĐœĐ°Đ»ĐžĐ·Đ° Đž ĐČŃ‹Đ±Ń€Đ°ĐœĐœĐŸĐłĐŸ ĐŒĐœĐŸĐ¶Đ”ŃŃ‚ĐČĐ° ĐżŃ€ĐžĐ·ĐœĐ°ĐșĐŸĐČ ĐżĐŸĐŽĐŸĐ±ĐžŃ. Đ Đ°Đ·Ń€Đ°Đ±ĐŸŃ‚Đ°ĐœĐœŃ‹Đč ĐżĐŸĐŽŃ…ĐŸĐŽ ĐżĐŸĐ·ĐČĐŸĐ»ŃĐ”Ń‚ Оз ĐŒĐœĐŸĐ¶Đ”ŃŃ‚ĐČĐ° Ń„ŃƒĐœĐșцоĐč ŃĐžŃŃ‚Đ”ĐŒŃ‹ ĐČŃ‹ĐŽĐ”Đ»ĐžŃ‚ŃŒ ĐżĐŸĐŽĐŸĐ±ĐœŃ‹Đ” (ĐżĐŸ ĐŸĐżŃ€Đ”ĐŽĐ”Đ»Đ”ĐœĐœŃ‹ĐŒ ĐżŃ€ĐžĐ·ĐœĐ°ĐșĐ°ĐŒ) Đž ĐŸĐ±ŃŠĐ”ĐŽĐžĐœĐžŃ‚ŃŒ ох ĐČ Đ°Ń€Ń…ĐžŃ‚Đ”ĐșŃ‚ŃƒŃ€ĐœŃ‹Đ” ĐșĐŸĐŒĐżĐŸĐœĐ”ĐœŃ‚Ń‹ (ŃƒĐœĐžŃ„ĐžŃ†ĐžŃ€ĐŸĐČĐ°ĐœĐœŃ‹Đ” Ń„ŃƒĐœĐșŃ†ĐžĐŸĐœĐ°Đ»ŃŒĐœŃ‹Đ” ĐŒĐŸĐŽŃƒĐ»Đž).Đ—Đ°ĐżŃ€ĐŸĐżĐŸĐœĐŸĐČĐ°ĐœĐŸ піЮхіЮ ĐŽĐŸ ĐżŃ€ĐŸĐ”ĐșтуĐČĐ°ĐœĐœŃ архітДĐșтуро Ń†Đ”ĐœŃ‚Ń€Ńƒ ĐŸĐ±Ń€ĐŸĐ±ĐșĐž Ń–ĐœŃ„ĐŸŃ€ĐŒĐ°Ń†Ń–Ń— Đ°ĐČŃ‚ĐŸĐŒĐ°Ń‚ĐžĐ·ĐŸĐČĐ°ĐœĐŸŃ— ŃĐžŃŃ‚Đ”ĐŒĐž ĐŒĐŸĐœŃ–Ń‚ĐŸŃ€ĐžĐœĐłŃƒ ŃĐ”Ń€Đ”ĐŽĐŸĐČоща ĐČ Ń€Đ”Đ°Đ»ŃŒĐœĐŸĐŒŃƒ часі, Ń‰ĐŸ Đ·Đ°ŃĐœĐŸĐČĐ°ĐœĐžĐč ĐœĐ° ĐșласОфіĐșації Ń„ŃƒĐœĐșŃ†Ń–ĐŸĐœĐ°Đ»ŃŒĐœĐžŃ… заЎач ĐœĐ° піЮстаĐČі ĐŒĐ”Ń‚ĐŸĐŽŃ–ĐČ ĐșĐ»Đ°ŃŃ‚Đ”Ń€ĐœĐŸĐłĐŸ Đ°ĐœĐ°Đ»Ń–Đ·Ńƒ і ĐŸĐ±Ń€Đ°ĐœĐŸŃ— ĐŒĐœĐŸĐ¶ĐžĐœĐž ĐŸĐ·ĐœĐ°Đș ŃŃ…ĐŸĐ¶ĐŸŃŃ‚Ń–. Đ ĐŸĐ·Ń€ĐŸĐ±Đ»Đ”ĐœĐžĐč піЮхіЮ ĐŽĐŸĐ·ĐČĐŸĐ»ŃŃ” ĐČОбратО Ń–Đ· ĐŒĐœĐŸĐ¶ĐžĐœĐž Ń„ŃƒĐœĐșціĐč ŃĐžŃŃ‚Đ”ĐŒĐž ŃŃ…ĐŸĐ¶Ń– (Đ·Đ° пДĐČĐœĐžĐŒĐž ĐŸĐ·ĐœĐ°ĐșĐ°ĐŒĐž) і ĐżĐŸŃ”ĐŽĐœĐ°Ń‚Đž їх ĐČ Đ°Ń€Ń…Ń–Ń‚Đ”ĐșŃ‚ŃƒŃ€ĐœŃ– ĐșĐŸĐŒĐżĐŸĐœĐ”ĐœŃ‚Đž (ŃƒĐœŃ–Ń„Ń–ĐșĐŸĐČĐ°ĐœŃ– Ń„ŃƒĐœĐșŃ†Ń–ĐŸĐœĐ°Đ»ŃŒĐœŃ– ĐŒĐŸĐŽŃƒĐ»Ń–).The approach to designing architecture of the information processing complex of the automated real time conditions monitoring system based on classification of functional tasks on the basis of methods of cluster analysis and the chosen set of similarity attributes is offered. The developed approach allows to allocate from a set of functions the systems similar (on certain attributes) and to unite them in architectural components (unified functional modules)

    Multi-messenger observations of a binary neutron star merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

    Search for High-energy Neutrinos from Binary Neutron Star Merger GW170817 with ANTARES, IceCube, and the Pierre Auger Observatory

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    Multi-messenger Observations of a Binary Neutron Star Merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ∌ 1.7 {{s}} with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of {40}-8+8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 {M}ÈŻ . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ∌ 40 {{Mpc}}) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∌10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ∌ 9 and ∌ 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.</p

    Does anyone pay attention to age-of-marriage laws?

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    Child and early marriage is associated with bad outcomes for women and girls. Though many countries have raised the legal age of marriage, the incidence early mar- riage remains stubbornly high. We develop a simple model of marriage behaviour to explain how effective laws create discontinuities or ‘jumps’ in the number of women getting married at the legal cut-off. We formally test for these discontinuities in real-world data using multiple rounds of the Demographic and Health Surveys (DHS) covering over 60 countries by applying distributional tests derived from the regression- discontinuity literature. Most countries are not actually enforcing the laws in their books, and enforcement is not getting better over time. A key contribution is there- fore a simple, tractable way to monitor legal efficacy using observational data that may help to create the feedback loop between national polices and the outcome that matters for women and girls. Separately, we demonstrate that various measures of age-of-marriage discontinuities are systematically related to with existing, popular measures of rule-of-law and government effectiveness. We conclude by arguing that using laws to enforce adult marriage will not be effective in many settings

    Corneal microprojections in coleoid cephalopods

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    The cornea is the first optical element in the path of light entering the eye, playing a role in image formation and protection. Corneas of vertebrate simple camera-type eyes possess microprojections on the outer surface in the form of microridges, microvilli, and microplicae. Corneas of invertebrates, which have simple or compound eyes, or both, may be featureless or may possess microprojections in the form of nipples. It was previously unknown whether cephalopods (invertebrates with camera-type eyes like vertebrates) possess corneal microprojections and, if so, of what form. Using scanning electron microscopy, we examined corneas of a range of cephalopods and discovered nipple-like microprojections in all species. In some species, nipples were like those described on arthropod compound eyes, with a regular hexagonal arrangement and sizes ranging from 75 to 103 nm in diameter. In others, nipples were nodule shaped and irregularly distributed. Although terrestrial invertebrate nipples create an antireflective surface that may play a role in camouflage, no such optical function can be assigned to cephalopod nipples due to refractive index similarities of corneas and water. Their function may be to increase surface-area-to-volume ratio of corneal epithelial cells to increase nutrient, gas, and metabolite exchange, and/or stabilize the corneal mucous layer, as proposed for corneal microprojections of vertebrates
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