Advanced experimental applications for x-ray transmission gratings Spectroscopy using a novel grating fabrication method

A novel fabrication method for soft x-ray transmission grating and other optical elements is presented. The method uses Focused-Ion-Beam (FIB) technology to fabricate high-quality free standing grating bars on Transmission Electron Microscopy grids (TEM-grid). High quality transmission gratings are obtained with superb accuracy and versatility. Using these gratings and back-illuminated CCD camera, absolutely calibrated x-ray spectra can be acquired for soft x-ray source diagnostics in the 100-3000 eV spectral range. Double grating combinations of identical or different parameters are easily fabricated, allowing advanced one-shot application of transmission grating spectroscopy. These applications include spectroscopy with different spectral resolutions, bandwidths, dynamic ranges, and may serve for identification of high-order contribution, and spectral calibrations of various x-ray optical elements

Measurement of L-shell emission from mid-Z targets under non-LTE conditions using Transmission Grating Spectrometer and DANTE power diagnostics

Producción CientíficaIn this work, we present the measurement of L-band emission from buried Sc/V targets in experiments performed at the OMEGA laser facility. The goal of these experiments was to study non-local thermodynamic equilibrium plasmas and benchmark atomic physics codes. The L-band emission was measured simultaneously by the time resolved DANTE power diagnostic and the recently fielded time integrated Soreq-Transmission Grating Spectrometer (TGS) diagnostic. The TGS measurement was used to support the spectral reconstruction process needed for the unfolding of the DANTE data. The Soreq-TGS diagnostic allows for broadband spectral measurement in the 120 eV–2000 eV spectral band, covering L- and M-shell emission of mid- and high-Z elements, with spectral resolution λ/Δλ = 8–30 and accuracy better than 25%. The Soreq-TGS diagnostic is compatible with ten-inch-manipulator platforms and can be used for a wide variety of high energy density physics, laboratory astrophysics, and inertial confinement fusion experiments

Tumour expression of leptin is associated with chemotherapy resistance and therapy-independent prognosis in gastro-oesophageal adenocarcinomas

Background: Cytotoxic chemotherapy remains the main systemic therapy for gastro-oesophageal adenocarcinoma, but resistance to chemotherapy is common, resulting in ineffective and often toxic treatment for patients. Predictive biomarkers for chemotherapy response would increase the probability of successful therapy, but none are currently recommended for clinical use. We used global gene expression profiling of tumour biopsies to identify novel predictive biomarkers for cytotoxic chemotherapy. Methods: Tumour biopsies from patients (n=14) with TNM stage IB–IV gastro-oesophageal adenocarcinomas receiving platinum-based combination chemotherapy were used as a discovery cohort and profiled with Affymetrix ST1.0 Exon Genechips. An independent cohort of patients (n=154) treated with surgery with or without neoadjuvant platinum combination chemotherapy and gastric adenocarcinoma cell lines (n=22) were used for qualification of gene expression profiling results by immunohistochemistry. A cisplatin-resistant gastric cancer cell line, AGS Cis5, and the oesophageal adenocarcinoma cell line, OE33, were used for in vitro validation investigations. Results: We identified 520 genes with differential expression (Mann–Whitney U, P<0.020) between radiological responding and nonresponding patients. Gene enrichment analysis (DAVID v6.7) was used on this list of 520 genes to identify pathways associated with response and identified the adipocytokine signalling pathway, with higher leptin mRNA associated with lack of radiological response (P=0.011). Similarly, in the independent cohort (n=154), higher leptin protein expression by immunohistochemistry in the tumour cells was associated with lack of histopathological response (P=0.007). Higher leptin protein expression by immunohistochemistry was also associated with improved survival in the absence of neoadjuvant chemotherapy, and patients with low leptin protein-expressing tumours had improved survival when treated by neoadjuvant chemotherapy (P for interaction=0.038). In the gastric adenocarcinoma cell lines, higher leptin protein expression was associated with resistance to cisplatin (P=0.008), but not to oxaliplatin (P=0.988) or 5fluorouracil (P=0.636). The leptin receptor antagonist SHLA increased the sensitivity of AGS Cis5 and OE33 cell lines to cisplatin. Conclusions: In gastro-oesophageal adenocarcinomas, tumour leptin expression is associated with chemoresistance but a better therapy-independent prognosis. Tumour leptin expression determined by immunohistochemistry has potential utility as a predictive marker of resistance to cytotoxic chemotherapy, and a prognostic marker independent of therapy in gastro-oesophageal adenocarcinoma. Leptin antagonists have been developed for clinical use and leptin and its associated pathways may also provide much needed novel therapeutic targets for gastro-oesophageal adenocarcinoma

Geological characteristics and latest progress in exploration and development of Russian shale oil

© 2019, OIL & GAS GEOLOGY Editorial Board. All right reserved. Russia is rich in unconventional shale oil resources, covering almost all sedimentary basins ranging from Cambrian to Neogene in age. The major areas of prospecting potential in Russia are the Bazhenov Formation of the Western Siberian platform and the Domanik formations in the Eastern European platform. Bazhenov Formation is the Upper Jurassic-Lower Cretaceous in age. Its main lithology is siliceous shale, with a thickness of 30 m and TOC of 7% on average. Its TOC is generally above 4%, mainly falling on kerogens TypeⅠ-Ⅱ domain, with the maturity ranging from 0.5% to 1.1%. While Domanik formations, also called "Domanik facies" or "Domanik deposits" from the Paleozoic Upper Devonian (Russian stage-D3 fr2) to Lower Carboniferous (Tournaisian-C1t) in age, in the Volga-Urals and Timan-Pecher oil and gas provinces, are dark siliceous-clayey-bituminous limestones falling on kerogens TypeⅠ-Ⅱ domain, with an overall thickness of 100-600 m, TOC of 0.5-24%, and maturity ranging from 0.5% to 1.5% in the north-central part of Volga-Ural Basin. However, their gas production is mainly concentrated on the southern part of Caspian sea. Despite of the unfavorable impact due to the low international oil prices, the exploration and development of shale oil resources in Russia have never been stopped: 146 vertical wells in the Bazhenov Formation were tested in 2016, with an average daily production rate of 10.8 t during the active days; meanwhile 36 horizontal wells were tested with an average daily production rate of 7.5 t during the active days. The Bazhenov technology center, set up by Gazprom in 2018, has cut down the time of hydraulic fracturing to 50%, and unit production cost to 40% in the development of Bazhenov oil. Moreover, the deve-lopment of shale oil resources in Russia can enjoy preferential policies like zero tax rate for mineral exploitations. Together with its existing favorable conditions, including abundant geological data for most oil fields, relatively short distances among these oil fields, and perfect infrastructures, the expectation is very positive for the future commercial development of shale oil in Russia

Geological characteristics and latest progress in exploration and development of Russian shale oil

© 2019, OIL & GAS GEOLOGY Editorial Board. All right reserved. Russia is rich in unconventional shale oil resources, covering almost all sedimentary basins ranging from Cambrian to Neogene in age. The major areas of prospecting potential in Russia are the Bazhenov Formation of the Western Siberian platform and the Domanik formations in the Eastern European platform. Bazhenov Formation is the Upper Jurassic-Lower Cretaceous in age. Its main lithology is siliceous shale, with a thickness of 30 m and TOC of 7% on average. Its TOC is generally above 4%, mainly falling on kerogens TypeⅠ-Ⅱ domain, with the maturity ranging from 0.5% to 1.1%. While Domanik formations, also called "Domanik facies" or "Domanik deposits" from the Paleozoic Upper Devonian (Russian stage-D3 fr2) to Lower Carboniferous (Tournaisian-C1t) in age, in the Volga-Urals and Timan-Pecher oil and gas provinces, are dark siliceous-clayey-bituminous limestones falling on kerogens TypeⅠ-Ⅱ domain, with an overall thickness of 100-600 m, TOC of 0.5-24%, and maturity ranging from 0.5% to 1.5% in the north-central part of Volga-Ural Basin. However, their gas production is mainly concentrated on the southern part of Caspian sea. Despite of the unfavorable impact due to the low international oil prices, the exploration and development of shale oil resources in Russia have never been stopped: 146 vertical wells in the Bazhenov Formation were tested in 2016, with an average daily production rate of 10.8 t during the active days; meanwhile 36 horizontal wells were tested with an average daily production rate of 7.5 t during the active days. The Bazhenov technology center, set up by Gazprom in 2018, has cut down the time of hydraulic fracturing to 50%, and unit production cost to 40% in the development of Bazhenov oil. Moreover, the deve-lopment of shale oil resources in Russia can enjoy preferential policies like zero tax rate for mineral exploitations. Together with its existing favorable conditions, including abundant geological data for most oil fields, relatively short distances among these oil fields, and perfect infrastructures, the expectation is very positive for the future commercial development of shale oil in Russia

Differentiating multi-MeV, multi-ion spectra with CR-39 solid-state nuclear track detectors.

The development of high intensity petawatt lasers has created new possibilities for ion acceleration and nuclear fusion using solid targets. In such laser-matter interaction, multiple ion species are accelerated with broad spectra up to hundreds of MeV. To measure ion yields and for species identification, CR-39 solid-state nuclear track detectors are frequently used. However, these detectors are limited in their applicability for multi-ion spectra differentiation as standard image recognition algorithms can lead to a misinterpretation of data, there is no unique relation between track diameter and particle energy, and there are overlapping pit diameter relationships for multiple particle species. In this report, we address these issues by first developing an algorithm to overcome user bias during image processing. Second, we use calibration of the detector response for protons, carbon and helium ions (alpha particles) from 0.1 to above 10&nbsp;MeV and measurements of statistical energy loss fluctuations in a forward-fitting procedure utilizing multiple, differently filtered CR-39, altogether enabling high-sensitivity, multi-species particle spectroscopy. To validate this capability, we show that inferred CR-39 spectra match Thomson parabola ion spectrometer data from the same experiment. Filtered CR-39 spectrometers were used to detect, within a background of ~ 2 × 1011&nbsp;sr-1&nbsp;J-1 protons and carbons, (1.3 ± 0.7) × 108&nbsp;sr-1&nbsp;J-1 alpha particles from laser-driven proton-boron fusion reactions