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The highly elastic behavior of fullerenelike carbon nitride thin films on single crystal Si (001) substrates has been studied by nanoindentation. The films exhibit a microstructure of frequently bent and intersecting graphene sheets. Transmission electron microscopy of indented areas revealed no tendency to plastic deformation in the highly elastic and compliant film. Also, a unique deformation pattern in the Si substrate is observed, where a {111} facetted inverted pyramid of untransformed Si remained intact under the indenter with a retained CNx/Si(001) interface. Analytical approaches using the effective indenter method, supported by finite element methods, are employed to understand the nonlinear but fully elastic behavior of the coatings as well as to describe the critical parameters for the deformation and phase transformation of the Si substrate. [ABSTRACT FROM AUTHOR]

Plasma probe measurements and energy selective mass spectrometry were used to characterize the composition and energetic conditions of the ion flux of a direct current, N[sub 2]/Ar, unbalanced magnetron sputtering plasma in front of a graphite target, depending on the total pressure and gas composition. It is shown that the flux of ionized film-forming species consist predominantly of C[sub x]N[sub y] (x,y<=2) species. The total number of C-containing ions strongly depends on the N[sub 2] fraction in the discharge and can be increased by almost one order of magnitude scaling with the availability of N[sub 2] as the discharge gas. This finding suggests that besides C and N atoms and ions, other species, like preformed C[sub x]N[sub y] particles, play an important role during growth of fullerene-like (FL) carbon nitride (CN[sub x]) thin films. It is proposed that such clusters have a direct effect as growth templates or nucleation sites on the evolution of curved and cross-linked FL structures. The carbon target was identified as the main source of preformed C-containing species, following from the pressure dependence of the ion energy distributions of the most abundant C[sub x]N[sub y] (x,y<=2) ions. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Fullerene-like (FL) carbon nitride (CN[sub x]) films were deposited on Si (100) substrates by dc reactive, unbalanced, magnetron sputtering in a N[sub 2]/Ar mixture from a high-purity pyrolythic graphite cathode in a dual-magnetron system with coupled magnetic fields. The N[sub 2] fraction in the discharge gas (0%-100%) and substrate bias (-25 V; -40 V) was varied, while the total pressure (0.4 Pa) and substrate temperature (450 °C) was kept constant. The coupled configuration of the magnetrons resulted in a reduced ion flux density, leading to a much lower average energy per incorporated particle, due to a less focused plasma as compared to a single magnetron. This enabled the evolution of a pronounced FL microstructure. The nitrogen concentration in the films saturated rapidly at 14-18 at. %, as determined by elastic recoil analysis, with a minor dependence on the discharge conditions. No correlations were detected between the photoelectron N1 s core level spectra and the different microstructures, as observed by high-resolution electron microscopy. A variety of distinct FL structures were obtained, ranging from structures with elongated and aligned nitrogen-containing graphitic sheets to disordered structures, however, not exclusively linked to the total N concentration in the films. The microstructure evolution has rather to be seen as in equilibrium between the two competing processes of adsorption and desorption of nitrogen-containing species at the substrate. This balance is shifted by the energy and number of arriving species as well as by the substrate temperature. The most exceptional structure, for lower N[sub 2] fractions, consists of well-aligned, multi-layered circular features (nano-onions) with an inner diameter of approximately 0.7 nm and successive shells at a distance of ∼0.35 nm up to a diameter of 5 nm. It is shown that the intrinsic stress formation is closely linked with the evolution and accommodation of the heavily bent... [ABSTRACT FROM AUTHOR]

Retinal dystrophies constitute a group of clinically and genetically heterogeneous diseases that cause visual impairment. As treatments are not readily available, readout assays performed in patient-derived cells can aid in the development and comparative analysis of therapeutic approaches. We describe a new method with which the localization of the retinitis pigmentosa GTPase regulator (RPGR) protein along the cilium can be used as a measure for treatment efficacy. In a patient-derived fibroblast cell line, we found that the RPGR protein is mislocalized along the ciliary axoneme. The patient carried a point mutation that leads to skipping of RPGR exon 10. We confirmed that this skipping is causative for the impaired localization of RPGR using a U7 small nuclear RNA (U7snRNA)-based antisense approach in control cells. Treatment of the patient-derived fibroblasts with therapeutic U1snRNA significantly corrected the proteins' mislocalization. In this proof of principle study, we show that detecting the RPGR protein along the cilium provides a reliable and quantifiable readout assay to evaluate the efficacy of therapies intended to correct or silence RPGR gene mutations. This method opens the possibility to compare different therapeutic agents, and thus facilitate the identification of treatment options for the clinically and molecularly complex RPGR-associated diseases. [ABSTRACT FROM AUTHOR]

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V-alloyed AlCrN hard coatings were deposited by reactive arc evaporation in an industrial-sized deposition system and subsequently annealed in ambient air at temperatures ranging from 550 to 700 °C in order to study the formation mechanisms of the desired lubricious oxides. The oxidized samples were investigated by means of secondary ion mass spectrometry depth profiling, x-ray diffraction, Raman spectroscopy, and analytical transmission electron microscopy. Vanadium diffusion in the oxidized part of the coating leads to the formation of a V-rich top layer containing AlVO4 and the desired lubricious oxide V2O5 followed by a V-depleted inner oxide layer consisting of a mixed or nanocrystalline (Al,Cr,V)2O3 on top of the intact AlCrVN coating. [ABSTRACT FROM AUTHOR]

A new method for chemical analyses of nitride-based hard coatings is presented. Raman band shifts in the spectra of Al x Cr1− x N coatings, deposited by physical vapour deposition from Al x Cr1− x targets with x T,Al = 0, 0.25, 0.50, 0.70 and 0.85, are calibrated using compositional data of the coatings derived by elastic recoil detection analysis (ERDA) and electron probe micro-analysis (EPMA). Inserting the composition-dependent Raman shift of a combinatorial acoustic-optic lattice mode into an empirically derived equation allows the determination of Al/Cr ratios of the coating with an accuracy of about ±2%. Spot, line and area analyses of coated cemented carbide and cold work steel samples by using a computer-controlled, motorized x, y-stage are demonstrated and the most important errors influencing precision and accuracy are discussed. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

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Stress development during growth of CN x films by unbalanced magnetron sputtering has been investigated with an in-situ laser deflection technique. The stress is initially tensile, then it becomes compressive, reaching a maximum of as much as 7 GPa. These are anomalously high stress levels compared with pure carbon, considering the low ion energies (28 eV) and ion-to-neutral arrival rate ratio (<1) employed. This phenomenon is explained by the formation of a fullerene-like microstructure and nitrogen substitution at the growth surface . An accompanying increased reactivity of carbon atoms promotes sp 3 bonding or other cross-linking of curved basal planes with resulting film densification. [ABSTRACT FROM AUTHOR]

The present paper presents the results of in depth process characterisation and microstructural investigation of fullerene-like carbon nitride (FL - CN[sub x]) coatings combined with deformation analysis, such as indentation testing, in order to assess its performance. Unbalanced reactive magnetron sputtering of graphite in a nitrogen containing atmosphere is essential for the growth of FL - CN[sub x] structures due to C[sub x]N[sub y] molecules, which are preformed in the process and may act as precursors or growth templates. The deposition process is best described as a hybrid of plasma vapour deposition and chemical vapour deposition. The fullerene-like (FL) structure leads to extraordinary mechanical properties which are assessed by nanoindentation. It exhibits a low work of indentation (usually a property associated with superhard materials) and also a low to moderate resistance to penetration. Therefore, deformation energy is predominantly stored elastically and released after unload giving it a tough and resilient character. In addition, the relatively low modulus leads to a spreading of the contact stresses over a larger volume and consequently to low stress gradients at the substrate/film interface. This hinders substrate/film delamination under load and therefore results in a high load bearing capability, while the coating asperities behave elastically with no tendency to brittle fracture in tribological contact. This characteristic combined with the low coefficient of friction reveals a coating which may be suitable for many tribological applications. [ABSTRACT FROM AUTHOR]

The influence of hydrogen content and ambient humidity on the electrical properties of carbon nitride (CNx) films deposited by reactive magnetron sputtering from a graphite target in Ar discharges mixed with N2 and H2 at a substrate temperature of 350°C have been investigated. Carbon films deposited in pure Ar exhibit a dark resistivity at room temperature of ∼4 × 10−2 Ωcm, while the resistivity is one order of magnitude lower for CN0.25 films deposited in pure N2, due to their denser morphology. The increasing H2 fraction in the discharge gas leads to an increased resistivity for all gas mixtures. This is most pronounced for the nitrogen-free films deposited in an Ar/H2 mixture, where the resistivity increases by over four orders of magnitude. This can be related to a decreased electron mobility as H inhibits the formation of double bonds. After exposure to air, the resistivity increases with time through two different diffusion regimes. The measured electrical properties of the films are related to the apparent film microstructure, bonding nature, and ambient humidity. [ABSTRACT FROM AUTHOR]

Thin fullerene-like CNx coatings deposited on hard substrates (e.g. SiC) show very shallow residual impressions when investigated by nanoindentation at displacements less than the coating thickness. The low work of indentation (i.e. the small area enclosed by the loading and unloading curves) of these materials implies a large amount of recovery of indent depth which is often associated with materials of high hardness. However, analysis of the unloading curves by the Oliver-Pharr method generates hardness values which are usually less than that of silicon. Detailed analysis of the loading curve shows three distinct regimes of behaviour corresponding to behaviour controlled by surface roughness, elastic deformation and plasticity. Measurements of Young's modulus from the elastic part of the loading curve, from the Oliver-Pharr method and from elastic wave measurements are all consistently low. This implies that the material behaves like a very hard rubber which undergoes considerable elastic recovery on unloading but does not have a very high resistance to penetration on loading. The very high H/E values for fullerene-like CNx confirms this view. [ABSTRACT FROM AUTHOR]

Thin fullerene-like CN[sub x] coatings deposited on hard substrates (e.g. SiC) show very shallow residual impressions when investigated by nanoindentation at displacements less than the coating thickness. The low work of indentation (i.e. the small area enclosed by the loading and unloading curves) of these materials implies a large amount of recovery of indent depth which is often associated with materials of high hardness. However, analysis of the unloading curves by the Oliver-Pharr method generates hardness values which are usually less than that of silicon. Detailed analysis of the loading curve shows three distinct regimes of behaviour corresponding to behaviour controlled by surface roughness, elastic deformation and plasticity. Measurements of Young's modulus from the elastic part of the loading curve, from the Oliver-Pharr method and from elastic wave measurements are all consistently low. This implies that the material behaves like a very hard rubber which undergoes considerable elastic recovery on unloading but does not have a very high resistance to penetration on loading. The very high H/E values for fullerene-like CN[sub x] confirms this view. [ABSTRACT FROM AUTHOR]

In a preceding study, we had reviewed and evaluated the anatomy sites available on the Internet. The evolution of the available sites, the disappearance of certain sites and the appearance of new sites led us to update this list. In addition, the German-speaking sites were included in the study, which previously included only the Anglophone and French-speaking sites. Forty-eight sites were indexed and their addresses are available on the site of the Laboratory of Anatomy of the Faculty of Medicine Lyon-Nord (). Compared to the scores allotted in 1998, we noted in 1999 a significant increase (p = 0.03) in the total score (12.13 ± 2.98 vs. 11,23 ± 2,28/20), which shows that the quality of the anatomic sites available on the Internet has improved. [ABSTRACT FROM AUTHOR]

Copyright of Anatomia Clinica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anatomia Clinica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Examines the effects of one session of instructions on the frequency of chronic nightmares and on self-rated distress. Method; Results; Conclusions.

The Internet undoubtedly has an important part to play in medical teaching, generally speaking, and particularly in anatomy. We therefore undertook to survey, list, explore and study the various sites written in French or English devoted to anatomy on the Internet in order to evaluate them. Sites were identified from their URL address, by search engine or by hypertext links found in already listed sites. Useless and non-relevant sites were excluded. Fifty-two sites were selected and evaluated as to their navigability, illustrations, text and general presentation. Addresses of theses sites are available on a web page (; section liens, section Galerie Virtuelle). This directory could be a very useful working tool for the use of teachers and students. It will be regularly updated. [ABSTRACT FROM AUTHOR]

Copyright of Surgical & Radiologic Anatomy is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The gastrocolic v. or Henle’s gastrocolic trunk was described in 1868 [9]. We suggest defining this vein as the confluence of the right gastroepiploic and right upper colic vv. We report two original cases of avulsion of the gastrocolic v. occurring during a blunt abdominal trauma. The aim of this paper is a description, based on the literature, of the anatomy of the gastrocolic v. in order to precise the lesional mechanism. The gastrocolic v. is present in 70% of individuals. It is short (less than 25 mm) but of major calibre (3 to 10 mm). The gastrocolic v. is situated close beneath the root of the transverse mesocolon, and travels along the anterior surface of the head of the pancreas. Anatomic variations are detailed and a meta-analysis of interpretable studies was made. Both the supra- and infra-mesocolic surgical approaches are described. The radiologic and surgical importance of the gastrocolic v. is discussed. The lesional mechanism in both our cases of injury of the gastrocolic v. is explained. [ABSTRACT FROM AUTHOR]

Fullerene-like CN[sub x] (xapprox. 0.12) thin solid films were deposited by reactive magnetron sputtering of graphite in a nitrogen and argon discharge on cleaved NaCl and Si(001) substrates at 450 °C. As-deposited films consist of 5 nm diam CN[sub x] nano-onions with shell sizes corresponding to Goldberg polyhedra determined by high-resolution transmission electron microscopy. Electron energy loss spectroscopy revealed that N incorporation is higher in the core of the onions than at the perimeter. N incorporation promotes pentagon formation and provides reactive sites for interlinks between shells of the onions. A model is proposed for the formation of CN[sub x] nano-onions by continuous surface nucleation and growth of hemispherical shells. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The NPAC visible human viewer (NPAC VHV), graphical interface written in JAVA, freely accessible by the Web, allows the display of anatomic cross-sections of the Visible Human Project developed by the National Library of Medicine. In April 1997, the Medical Media Library of Lyons undertook the construction of a French-language mirror site of the NPAC VHV. The aim of this work is to evaluate first year utilisation of this site. From May 1st, 1997 to April 30th, 1998, the mirror site was consulted 34,752 times. In 45.14% of cases, the request came from France, in 4.42% of cases from Belgium, in 3.98% from Canada and in 2.12% from Switzerland. Other connections came either from a country responsible for fewer than 1% of connections or from unidentified computers. Data analysis showed a peak of connections between 15:00 and 17:00, and an increased number of connections from September to March 1998. The NPAC VHV is housed in 5 sites in the world. It is a software very simple to use. As the figures have no legends, it is more appropriate for group teaching than for self-teaching. [ABSTRACT FROM AUTHOR]

Our recent experience stimulated a review of selective rhizotomies for the alleviation of localized pain. Three patients with postoperative neuralgia in the inguinal region and two with neoplastic root compression were treated. Results were good and long-lasting in two cases, moderate in two and poor in one case. The relief appeared to be better, the more clearly the pain was localized. In lesions distal to the spinal root it is necessary to undertake selective paravertebral root blocks with local anaesthetics. Experimental data are discussed that help in an understanding of pain recurrence after rhizotomy. [ABSTRACT FROM AUTHOR]

Nanocomposite Cr-B-N coatings were deposited from CrB0.2 compound targets by reactive arc evaporation using an Ar/N2 discharge at 500 °C and -20 V substrate bias. Elastic recoil detection (ERDA), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and selected-area electron diffraction (SAED) were used to study the effect of the N2 partial pressure on composition and microstructure of the coatings. Cross-sectional scanning electron microscopy (SEM) showed that the coating morphology changes from a glassy to a columnar structure with increasing N2 partial pressure, which coincides with the transition from an amorphous to a crystalline growth mode. The saturation of N content in the coating confirms the formation of a thermodynamically stable CrN-BN dual-phase structure at higher N2 fractions, exhibiting a maximum in hardness of approximately 29 GPa. [ABSTRACT FROM AUTHOR]