Six different source chemicals (organosilanes) were successfully used for deposition of self-assembled monolayers (SAMs) onto silicon substrates by a vapor phase process. Five different fluorocarbon coatings and one hydrocarbon coating were deposited. The thermal stability of the coatings was studied in detail with respect to degradation as a function of temperature, and for the fluorocarbon coatings also the degradation rate at 400 • C. For fluorocarbon coatings deposited from FDTS a useful lifetime of approximately 90 min at 400 • C was found allowing the coating to survive high temperature MEMS packaging operations, while fluorocarbon coatings deposited from FOTS, FOMDS, FOTES and FOMMS were less stable. The hydrocarbon coating deposited from OTS degrades already at approximately 200 • C. The thermal stability of the SAM coatings was found to be significantly reduced if aggregations from the deposition process are present on the coatings.
In the oil and gas industry there is a growing demand for riser solutionsdedicated to high partial pressures of CO2. Part of this demand is driven bydeep water high pressure reservoirs with high CO2 content. In addition there isa growing interest in reinjection of CO2. The reinjection can be driven by adesire to reduce CO2 emission as in Carbon Capture and Storage (CCS) projects, but also as a way of Enhanced Oil Recovery (EOR). In all cases it is likelythat CO2 will be present at high pressures and in its supercriticalphase. NKT Flexibles is about to complete a three-year documentation and qualificationprogram with the aim of qualifying a broad range of flexible pipe solutions foruse with supercritical CO2 (SCCO2). An important part of the program has beenmaterial qualification. For polymeric materials, the main challenge is the highsolubility in some polymers of supercritical CO2. This leads to potential highswelling and a risk of mechanical damage (blistering) in explosivedecompression situations. Furthermore, supercritical CO2 has a strongextraction power which may result in rapid loss of plasticizer in plasticizedpolymers. The qualification program included a broad variety of tests qualifying againstpotential failure mechanisms. The testing program is executed on polymers incontact with the bore stream. Results show that cross-linked poly-ethylene(XLPE) inner liner has superior resistance to SCCO2 on all tested parameterscompared to other available liner materials. For steel materials, the main potential risk when exposed to supercritical CO2is corrosion. High CO2 content together with water forms a corrosiveenvironment which could have some impact on the metals used. For flexible pipeapplication, this is primarily relevant for the carcass material and endfitting which is in direct contact with the bore stream. Selection ofappropriate metallic materials will be based on the actual specification of thebore stream. This paper will present the full scope and results of the qualification workcompleted for qualification of flexible dynamic risers for SCCO2. Introduction For the last 35 years, unbonded flexible pipes have been a key component inoffshore oil and gas production. They represent an alternative solution torigid steel pipes where they have the advantages of faster installation timesand better adapting potential for changes in field layout. These advantagesoften make unbonded flexible pipes a more economical solution than rigid steelpipes.
Avulsions dentaires et kystectomies chez les patients présentant un déficit constitutionnel en facteurs de l'hémostase : conduite à tenir SOCIÉTÉ FRANCOPHONE DE MÉDECINE BUCCALE ET DE CHIRURGIE BUCCALE Article pédagogique Remerciements : Le groupe de travail tient à remercier pour leur collaboration à ce travail Mesdames Marie Claude LINCHET (secrétaire médicale, Hôpital Cochin), Geneviève JOLIVET (cadre infirmier, Hôpital Cochin) et Elisabeth TONNEL (manipulatrice en radiologie, Hôpital Cochin).
In the oil and gas industry there is a growing demand for riser solutions dedicated to high partial pressures of CO 2 . The demand is primarily driven by deep water high pressure reservoirs with high CO 2 content. In addition there is a growing interest in reinjection of CO 2 . The reinjection can be driven by a desire to reduce CO 2 emission as in Carbon Capture and Storage (CCS) projects, but also as a method for Enhanced Oil Recovery (EOR). In all cases it is likely that CO 2 will be present at high pressures and in its supercritical phase.NOV Flexibles has in recent years developed dedicated riser solutions for a broad range of flexible pipe applications for use with high pressure dense phase CO 2 also referred to as supercritical CO 2 (SCCO2). An important part of the qualification program has been material qualification. For polymeric materials, the main challenge is the high solubility in some polymers of high pressure CO 2 . This leads to potential high swelling and a risk of mechanical damage (blistering) in explosive decompression situations. Furthermore, high pressure CO 2 has a strong extraction power which may result in rapid loss of plasticizer in plasticized polymers. This paper describes the latest status and achievements in the qualification program including a broad variety of tests qualifying against potential failure mechanisms to CO 2 pressures in the range of 650 to 700 bar. The results show that peroxide cross-linked poly-ethylene (XLPE) in-line cured inner liner with a high degree of cross linking has superior resistance to high pressure CO 2 on all tested parameters compared to other available liner materials. This makes it the preferred liner material for ultra high pressure CO 2 gas risers and flowlines whereas PVDF is the optimum choice for production risers with temperatures above 90 °C and intermediate CO 2 partial pressures.
The aging tissue microenvironment undergoes progressive changes enabling age-related pathologies. Senescent cells increase with age, and the secretome released from senescence cells (SASP) affects neighboring cells, often promoting proliferation, tissue inflammation, angiogenesis, and, depending on tissue type, creating a milieu favoring neoplasia. We showed that local non-pituitary growth hormone (GH) accumulates with age in human colon tissue, is induced in response to DNA damage, and suppresses DNA repair. We now show that GH is a SASP component. To examine SASP-derived GH actions on the tissue microenvironment, we co-cultured intact human 3D intestinal organoids with organoids infected with lentivirus expressing either hGH (lentiGH) or vector (lentiV) for 5 weeks. Using whole-exome sequencing to evaluate somatic mutations and somatic copy number alterations, we found that local paracrine GH emanating from lentiGH organoids increases chromosomal instability in intact organoid cells, inducing somatic mutations including deletions, breakends, duplications, and insertions, as compared to organoids co-cultured with lentiV organoids. Mechanisms for chromosomal instability observed in these organoids likely occur as a consequence of GH-induced suppression of DNA damage repair proteins including pATM, pATR, and pBRCA2, leading to DNA damage accumulation, and, in the long run, favoring cell transformation. KEGG pathway analysis of intact organoids subjected to paracrine GH exposure identified changes in focal adhesion pathways (p=0.0016), consistent with observed increased migration, invasion, and anchorage-independent growth of normal human colon cells (hNCC) exposed to GH. Furthermore, IPA analysis revealed EMT pathway changes (p=0.0018),,also confirmed by showing increased EMT transcription factors Twist2 and Snai1 expression.Although senescence has been defined as irreversible proliferative arrest, recent studies now show that senescence can be reversed. Treating hNCC with etoposide to induce senescence and culturing senescent cells in the presence of GH for 10 days resulted in p53 suppression, enabling cells to re-enter the cell cycle, as evidenced by induced Ki67, a marker of proliferation. These post-senescent cells also acquired the stem cell marker SOX2 and exhibited increased Twist2, consistent with anchorage-independent growth and increased migration as compared to senescence cells not treated with GH. These results identify local paracrine GH as an important determinant of the local tissue microenvironment promoting age-associated changes consistent with a pro-neoplastic milieu. Citation Format: Vera Chesnokova, Svetlana Zonis, Tugce Apaydin, Christian Wang, Robert Barrett, Shlomo Melmed. Mechanisms of growth hormone action in the aging tissue microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 300.
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