Search results for "RADIATION"

Microanalytical methods for in-situ high-resolution analysis of rock varnish at the micrometer to nanometer scale

2015

Abstract A wide range of analytical techniques were used to investigate rock varnish from different locations (Negev, Israel; Knersvlakte, South Africa; Death Valley and Mojave Desert, California): a 200 nm-femtosecond laser ablation-inductively coupled plasma-mass spectrometer (LA-ICP-MS), an electron probe microanalyzer (EPMA), focused ion beam (FIB) slicing, and scanning transmission X-ray microscopy–near edge X-ray absorption fine structure spectroscopy (STXM–NEXAFS). This combination enables comprehensive high-spatial-resolution analysis of rock varnish. Femtosecond LA-ICP-MS and EPMA were used for quantitative determination of element concentrations. In-situ measurements were conducte…

Re-irradiation With Carbon Ion Radiotherapy for Pelvic Rectal Cancer Recurrences in Patients Previously Irradiated to the Pelvis

2020

Background/Aim: Re-irradiation of locally recurrent rectal cancer poses challenges due to the proximity of critical organs, such as the bowel. This study aimed at evaluating the safety and efficacy of re-irradiation with Carbon Ion Radiotherapy (CIRT) in rectal cancer patients with local recurrence. Patients and Methods: Between 2014 and 2018, 14 patients were treated at the National Center of Oncological Hadrontherapy (CNAO Foundation) with CIRT for locally recurrent rectal cancer. Results: All patients concluded the treatment. No G≥3 acute/late reaction nor pelvic infections were observed. The 1-year and 2-year local control rates were, 78% and 52%, respectively, and relapse occurred clos…

Paget's disease of scrotum and penis case report of a re-irradiation and review of the literature.

2020

Extramammary Paget's disease (EMPD) is a rare cutaneous adenocarcinoma generally arising in the anogenital region. Surgery is still considered the treatment of choice for patients with EMPD, while Radiotherapy is a common alternative for inoperable cases and it's necessary in case of lack of surgical radicality. In this article, we described our experience and a review of the literature, with a particular focus on radiation-induced toxicity and on the feasibility of re-irradiation. A 70-year-old patient with EPMD underwent adjuvant radiotherapy in 2015. After 28 months for recurrence another radiant treatment was performed. No G3 (CTCAE v4) toxicity were recorded. In the last follow-up visi…

Analytical control of photocatalytic treatments: degradation of a sulfonated azo dye

2003

The degradation of Methyl Orange (C(14)H(14)N(3)SO(3)Na), chosen as a model sulfonated azo dye, was investigated in aqueous solutions containing suspended polycrystalline TiO(2) particles under irradiation with simulated sunlight. The dye disappearance and the formation of the mineralization end products were monitored; the formation of the main transient intermediates was also examined in detail. Particular attention was devoted to the identification and to the evolution of fragments retaining the chromophoric group. The comparison of data coming from various analytical techniques led to a possible reaction mechanism for the degradation process, giving insight into an aspect of the treatme…

Photooxidative behaviour of polyethylene/polyamide-6 blends

2010

International audience; The photochemical behaviour of several polyethylene/polyamide-6 blends was studied under conditions of artificial accelerated weathering. Particular attention was paid to five different compositions ranging from pure polyethylene to pure polyamide with blends of PE/PA-6 of various compositions: 75/25, 50/50 and 25/75 wt/wt%. Analysis by infrared spectroscopy of the chemical modifications caused by photooxidation showed that exposing the polyethylene/polyamide-6 blends to UV-light irradiation led to the formation of oxidation photoproducts in both polymer phases. In agreement with both the mechanical and spectroscopic analyses, the photooxidation rate of the blends wa…

Residual Stresses and Reactivity of Solids. Determination and Part Plaid in the Reaction Mechanisms

1996

Dichroic atomic vapor laser lock with multi-gigahertz stabilization range

2016

A dichroic atomic vapor laser lock (DAVLL) system exploiting buffer-gas-filled millimeter-scale vapor cells is presented. This system offers similar stability as achievable with conventional DAVLL system using bulk vapor cells, but has several important advantages. In addition to its compactness, it may provide continuous stabilization in a multi-gigahertz range around the optical transition. This range may be controlled either by changing the temperature of the vapor or by application of a buffer gas under an appropriate pressure. In particular, we experimentally demonstrate the ability of the system to lock the laser frequency between two hyperfine components of the $^{85}$Rb ground state…

Topochemical Reduction of La2NiO3F2: The First Ni-Based Ruddlesden–Popper n = 1 T′-Type Structure and the Impact of Reduction on Magnetic Ordering

2020

Within this study, we show that a broad range of reduced phases La2NiO3F2−Δ can be derived from Ruddlesden–Popper-type La2NiO3F2 using a reductive topochemical defluorination method based on reacti...

Heterogeneous Sonogashira Coupling over Nanostructured SiliaCat Pd(0)

2012

Sol–gel entrapped catalyst SiliaCat Pd(0) heterogeneously mediates the Sonogoashira coupling of different aryl halides and phenylacetylene either under thermal conditions or, much more efficiently, under microwave irradiation, affording good conversions of coupled products. Leaching of valued Pd is limited, and the catalyst can be reused.

Mapping and structure of DMXL1, a human homologue of the DmX gene from Drosophila melanogaster coding for a WD repeat protein.

2000

The DmX gene was recently isolated from the X chromosome of Drosophila melanogaster. TBLASTN searches of the dbEST databases revealed sequences with a high level of similarity to DmX in a variety of different species, including insects, nematodes, and mammals showing that DmX is an evolutionarily highly conserved gene. Here we describe the cloning of the cDNA and the chromosomal localization of one of the human homologues of DmX, Dmx-like 1 (DMXL1). The human DMXL1 gene codes for a large mRNA of 11 kb with an open reading frame of 3027 amino acids. The putative protein belongs to the superfamily of WD repeat proteins, which have mostly regulatory functions. The DMXL1 protein contains an exc…