Incomplete Layer Research Articles

Influence of a magnesium‐fluoride coating of magnesium‐based implants (MgCa0.8) on degradation in a rabbit model

MgCa0.8 cylinders (2.5 x 25 mm(2)) were coated with a magnesium-fluoride layer and implanted in the marrow cavities of both tibiae of 10 New Zealand White rabbits. The implantation duration was 3 and 6 months. The implants were clinically well tolerated. Micro-computed tomography revealed a new bone formation at the edges of the implants as well as an endosteal and periosteal remodeling. Using EDX-analysis, a calcium and phosphorus rich degradation layer could be found on the implant surface. It was covered by an incomplete layer containing fluoride. The analysis by weight before implantation and after 3 and 6 months, respectively, showed a slight decrease in volume in comparison to uncoated implants. When compared with uncoated implants, the mechanical properties of the coated implants exhibited a reduction in strength after 3 months. After 6 months, the strength of the coated implants was higher than that of uncoated cylinders.

A case of double Gantzer's muscle and its possible role in nerve entrapment

Department of Anatomy and Biology, Osaka Medical College, Takatsuki, Osaka, JapanAnomalous variants are essential for teaching bothanatomists and surgeons. Muscle anomalies of theupper extremity are recognized causes of periph-eral nerve disorder (Jones et al., 1997; Pai et al.,2008). Gantzer’s muscle (GM) or accessory head offlexor pollicis longus (FPL) has been implicated inKiloh-Nevin (i.e., ‘‘anterior interosseous’’ nerve)syndrome (Rask, 1979; Oh et al., 2000; Mahakka-nukrauh et al., 2004; Pai et al., 2008). Moreover,both GM and fibrous arch of flexor digitorum sub-limes (FDS) are considered as possible anatomicalfactors for median nerve (MN) entrapment neurop-athy (Lee and LaStayo, 2004; Bilecenoglu et al.,2005). Two GMs (Fig. 1) were detected in the rightforearm of an old Japanese male cadaver duringpractical anatomy course for undergraduate medi-cal students at Osaka medical college. Thesemuscles were present at two different anatomicalplanes. One of them, the deep GM (DGM), waslarger, voluminous in shape, and originated fromthe medial epicondyle of humerus and inserted intothe ulnar side of FPL muscle at the junctionbetween proximal and middle thirds of forearm.The second one or superficial GM (SGM) wassmaller and fusiform in shape and arose from theundersurface of humeroulnar head of FDS muscleand terminated distally into the FPL close and lat-eral to insertion of DGM. The MN passed superficialto the deep head of pronator teres (PT) musclewhere it gave the anterior interosseous nerve(AIN) just distal to the lower border of the crossedmuscle. The AIN arose from the lateral side of MNand both nerves coursed distally between twomyo-fibro-tendinous layers; the fibrous arch of FDSand SGM superficially and the DGM deeply. It hasbeen reported that the arcuate ligament of Fearnand Goodfellow is the fibrous tissue that blends to-gether from the PT and FDS muscles and can catchboth the AIN and MN in some patients sufferingMN compressive neuropathy (Rask, 1979). In ourcase, the origin of AIN from the radial side of MNwas reported by Ashworth et al. (1997). The AINdescended radial to the DGM, gave branches toboth SGM and FPL, sank deep to the tendon ofSGM and then passed deep to FPL where it reap-peared again medial to the latter muscle on theinterossous membrane. The manner of proximaland distal attachments, the shape as well as theinnervation of GMs, have been reported by others(Oh et al., 2000; Mahakkanukrauh et al., 2004;Pai et al., 2008). It seems that both MN and AINwere caught in intermuscular tunnel roofed by theSGM and FDS and floored by the DGM. The pres-ence of both DGM and SGM in addition to fibrousarch of FDS may be involved in MN and AIN com-pressive neuropathy. Moreover, the presence oftwo GMs may result in restricted movement of FPLand subsequent pain in lower forearm as reportedby others (Ryu and Watson, 1987; Pai et al.,2008). On the other hand, the GMs may be impor-tant in local transfers for restoring function in mul-tiple nerve palsies (Pai et al., 2008). The accessoryheads of the flexor muscles have been described inprimates and other mammals (pigs, foxes, andmarmots) as a muscle belly that connects themedial epicondyle origin of the FDS with the moreor less differentiated deep flexors muscle. Theflexor muscles of the forearm that develop fromthe flexor mass divide into two layers, superficialand deep. The FDS, FPL, and flexor digitorum pro-fundus originate from the deep layer. The existenceof accessory muscles connecting the flexor musclescould be explained by the incomplete cleavage ofthe deep layer of the flexor mass during develop-ment (Jones et al., 1997). This is the first report inthe literature regarding the presence of two GMsarising from different proximal attachments at two

Pinning potential in thick PrBa 2Cu 3O x/YBa 2Cu 3O 7−δ quasi-multilayers

Using Pulsed Laser Deposition we have fabricated thick quasi-multilayers composed of incomplete layers of PrBa 2Cu 3O x (PrBCO) nano-dots and layers of YBa 2Cu 3O 7− δ (YBCO). The number of such sequences was between 2 and 6, with the thickness of individual YBCO layers between 565 and 885 nm, and total thickness between 1.13 and 5.31 μm. For the thinner quasi-multilayer, DC magnetization studies showed an increase in the critical current density J c at all fields in comparison with a pure YBCO reference sample, while the thicker samples showed an increased J c only in high fields. We have also investigated the frequency dependence of J c from AC susceptibility studies and found that the pinning potential is well described by a logarithmic dependence on current density. Pinning potentials in PrBCO/YBCO quasi-multilayers also proved to be higher than in the reference sample at high fields. From angle-dependent transport measurements we have found indications of strong pinning centres induced by the (PrBCO) nano-dots, both isotropic and c-axis correlated.

Growth and Optical Properties of Gold Nanoshells Prior to the Formation of a Continuous Metallic Layer

The growth and optical properties of incomplete gold layers on silica particles (229 nm) are studied using visible/near-infrared spectroscopy and transmission electron microscopy. The gold particles that eventually coalesce to form a continuous gold layer are found to have droplet-like shapes. The optical properties of these systems are different from those of complete gold nanoshells. Using the discrete dipole approximation, it is found that the plasmon modes of such systems should exhibit two bands: one from 500-600 nm ("high energy") and the other from 600-800 nm ("low energy"). The calculations show that, for increasing coating density of the droplet-like particles, the lower energy band (i) becomes stronger relative to the higher energy band and (ii) is red-shifted. Both of these trends are found in the spectra of the prepared particles. Furthermore, the observed plasmon bands fall within the limits established by the model.

Changes in the Peritubular Tissue of Rat Testis after Cadmium Treatment

The present study demonstrates histological and immunohistochemical changes in the peritubular testicular tissue of rat testis after application of cadmium chloride. After 5-day cadmium exposure, advanced deterioration of the boundary testicular tissue, mainly oedema, disarrangement of collagen fibres and peritubular cells, dilatation and thrombosis of blood vessels were observed. Changes in the boundary tissue were accompanied with desquamation of the germinal epithelium. Immunohistochemically, positive reaction for alpha-smooth muscle actin and desmin in tunica media of large testicular blood vessels basically was not affected. No reaction for vimentin was seen in endothelial cells of blood capillaries, whereas positive reaction presented only these cells in large blood vessels. The myofibroblasts positively reacting for desmin and alpha-smooth muscle actin form a single incomplete layer in the lamina propria of seminiferous tubules. Vimentin reactivity in the myofibroblasts and in the supporting Sertoli cells as well as Leydig cells in damaged testicular tissue was not observed. An increase in fibroblasts and free inflammatory cells positive for vimentin in the peritubular space on the peripheric area of the testis was observed.

Structure investigation of the (100) surface of the orthorhombicAl13Co4crystal

We present a detailed study of the (100) surface of the orthorhombic ${\text{Al}}_{13}{\text{Co}}_{4}$ crystal using both experimental and ab initio computational methods. This complex metallic alloy is an approximant of the decagonal Al-Ni-Co quasicrystalline phase. After sputter-annealing preparation of the surface at 1073 K, the low-energy electron diffraction pattern recorded exhibits a pseudotenfold symmetry with lattice parameters consistent with those of the bulk model. At this stage, scanning tunneling microscopy (STM) measurements reveal two different types of surface terminations. A comparison between these two surface structures and the bulk planes indicate that the terminations correspond either to an incomplete puckered layer $(P)$ or to an incomplete flat layer $(F)$. At 1173 K, the majority of the surface consists of $P$ layer terminations. STM images calculated from our proposed surface model are in good agreement with experimental images. X-ray photoelectron diffraction patterns and single scattering cluster calculations further confirm that the local atomic arrangements present in the bulk model are preserved within the near-surface region.

Live offspring from vitrified blastocysts derived from fresh and cryopreserved ovarian tissue grafts of adult mice

Ovarian tissue cryopreservation and transplantation can be used to preserve fertility for cancer patients. In this study, we assessed the viability and function of ovarian tissue from adult mice that was cryopreserved by solid surface vitrification or traditional slow-cooling using various in vitro and in vivo techniques, including allotransplantation, in vitro oocyte maturation, embryo culture in vitro, blastocyst cryopreservation, embryo transfer, and development. The importance of cumulus cells for oocyte maturation, fertilization, and embryo development was investigated. Graft recovery, follicle survival, and oocyte retrieval was similar in control, vitrified, and slow-cooled groups. High rates of oocyte maturation, cleavage, and blastocyst formation were achieved, with no significant differences between the control, vitrified or slow-cooled ovarian tissue grafts. The presence of cumulus cells was important for oocyte maturation, fertilization, and subsequent development. Cumulus-oocyte complexes with no surrounding cumulus cells (N-COCs) or with an incomplete layer (P-COCs) had significantly lower rates of oocyte maturation and blastocyst formation than cumulus-oocyte complexes with at least one complete layer of cumulus cells (F-COCs; maturation rate: 63, 78 vs 94%; blastocyst rate: 29, 49 vs 80%). Live births were achieved using vitrified blastocysts derived from oocytes taken from vitrified and slow-cooled ovarian tissue heterotypic allografts. Successful production of healthy offspring from these vitrified blastocysts suggests that this technique should be considered as a useful stage to pause in the assisted reproduction pathway. This provides an alternative protocol for restoring fertility and offering cancer patients a better indication of their chances of pregnancy and live birth.

Evaluation of the True Self-etching Potential of a Fourth Generation Self-adhesive Methacrylate Resin–based Sealer

Introduction The limited diffusion of self-adhesive resin cements into crown dentin raises doubts on whether self-adhesive root canal sealers are capable of creating micromechanical retention in instrumented canal walls in the absence of adjunctive use of calcium chelating irrigants. This study evaluated the true self-etching potential of MetaSEAL, a self-adhesive sealer. Methods Mixed MetaSEAL sealer was applied to (1) fractured radicular dentin that was devoid of smear layers, (2) instrumented canal wall radicular dentin that was irrigated with water as the final rinse to preserve the smear layer, and (3) instrumented canal wall radicular dentin that was irrigated with ethylenediaminetetraacetic acid (EDTA) as the final rinse to remove the smear layer. Cryofractured tooth halves without sealer application were examined by scanning electron microscopy to identify the characteristics of the bonding substrates. The other tooth-halves were filled with sealer and processed for transmission electron microscopy. Results MetaSEAL did not demineralize fractured radicular dentin that was devoid of smear layer and smear plugs. The self-adhesive sealer was incapable of etching beyond the 1- to 2-μm-thick smear layer retained on water-irrigated instrumented dentin to demineralize the underlying radicular dentin. Smear layer and smear plugs were absent in EDTA-irrigated radicular dentin. The EDTA also partially demineralized the intact dentin, creating a thin bed of collagen for infiltration of the self-adhesive sealer. Conclusions The limited self-etching potential of MetaSEAL is a clinically legitimate concern. Incomplete smear layer removal from instrumented canal wall regions that are not reached by calcium chelating agents might jeopardize its bonding and sealing performance.

Bonding of Self-adhesive (Self-etching) Root Canal Sealers to Radicular Dentin

The latest generation of methacrylate resin–based sealers has eliminated the use of separate self-etching primers by incorporating acidic resin monomers in the sealers to render them self-adhesive to dentin. This study examined the adhesive strengths, interfacial ultrastructure, and tracer penetration of a nonetching (EndoREZ; Ultradent, South Jordan, UT) and two self-adhesive methacrylate resin–based sealers (MetaSEAL; Parkell, Farmington, NY, and RealSeal SE; SybronEndo, Orange, CA) when they were applied to radicular dentin following the manufacturers' recommended use of EDTA as the active final rinse. A modified push-out testing design was used to evaluate the dislodgement of core-free sealers. The mixed sealers were placed in dimensionally identical, artificially created canal spaces prepared in the coronal, middle, and apical thirds of radicular dentin. After setting, each sealer-filled cavity was subjected to compressive loading until failure. Additional specimens were prepared for transmission electron microscopy to examine the ultrastructure and nanoleakage within the sealer-radicular dentin interface. The two self-adhesive sealers MetaSEAL and RealSeal SE exhibited higher push-out strengths than the nonetching sealer EndoREZ when EDTA was used as the active final rinse. All three sealers showed a 1- to 1.5-μm thick zone of partially demineralized dentin, with the EDTA dentin demineralization effect masking the true self-etching potential of MetaSEAL and RealSeal SE. The true self-etching potential of self-adhesive sealers is a clinically important attribute that should be further investigated. Incomplete smear layer removal from the apical third of instrumented canal walls may jeopardize the performance of self-adhesive sealers should they fail to self-etch without the adjunctive use of calcium chelating irrigants.

Charge Trapping in Intergrain Regions of Pentacene Thin Film Transistors

AbstractA scanning Kelvin probe microscopy (SKPM) study of the surface potential of vacuum sublimed pentacene transistors under bias stress and its correlation with the film morphology is presented. While for thicker films there are some trapping centers inhomogeneously distributed over the film, as previously reported by other authors, by decreasing the film thickness the effect of thin intergrain regions (IGRs) becomes clear and a very good correlation between the topography and the potential data is observed. It is shown that in the thick pentacene grains the potential is homogeneous and independent of the gate bias applied with negligible charge trapping, while in the thin IGRs the potential varies with the applied gate bias, indicating that only an incomplete accumulation layer can be formed. Clear evidence for preferential charge trapping in the thin IGRs is obtained.

156 ENZYMATIC DISSOCIATION AND VITRIFICATION OF PREANTRAL FOLLICLES FROM THREATENED CARNIVOROUS MARSUPIALS

The mammalian ovary contains a rich resource of immature preantral follicles present regardless of cycle stage or seasonality. These follicles can be harvested enzymatically and are preserved more successfully than larger, more mature follicles. Thus, the collection and storage of preantral follicles is an applicable technique for the opportunistic harvesting of ovarian tissue from wildlife for the purpose of genebanking. This study examined the potential of such tools for the conservation of two endangered Australian carnivorous marsupials (dasyurids): the northern quoll, Dasyurus hallucatus, and the Tasmanian devil, Sarcophilus harrisii. The fat-tailed dunnart, Sminthopsis crassicaudata, is a representative model dasyurid with the typical attributes of large gametes (220 μm oocytes) and short polyovular reproductive cycles. Ovarian tissue was dissociated with 0.05–0.1% collagenase and 0.01–0.02% DNase in DMEM (all Sigma-Aldrich, St. Louis, USA) for up to 30 min before being neutralized with DMEM +10% fetal calf serum (FCS, Trace Biosciences, Castle Hill, Australia). Survival was determined using membrane permeability stains targeted to the nucleus (SYBR14 and propidium iodide, Molecular Probes, Carlsbad, CA, USA) or cytoplasm (trypan blue, Sigma) and assessed with a four-level survival score (1 = 100% live, 2 = 50–99% live, 3 = 1–49% live, 4 = 0% live) for each stage of follicular maturation: primordial (PF), early (EF), and late (LF) primary and secondary (SF) follicles (n = 100 each). Dissociated EF and LF (n = 45) from S. crassicaudata were vitrified with a three-step medium composed of up to 18% DMSO and ethylene glycol in 1 m sucrose (all Sigma; Vajta G et al. 1998 Mol. Reprod. Dev. 51, 53–58), and post-thaw viability was confirmed with trypan blue. All experiments were carried out on at least three individuals; values are presented as mean ± SEM and differences were determined with ANOVA and post hoc Tukey tests. In all species, 100% of PF were highly viable (score 1) and there was a significant decrease (P < 0.05) in the percentage of highly viable PF, EF, and LF when compared with SF, which were most commonly observed with minor damage (score 2). An incomplete layer of granulosa cells was observed in 11.92 ± 1.08% of freshly dissociated S. crassicaudata follicles. This increased to 30.34 ± 12.22% after preservation. Of the surrounded follicles, 48.40 ± 14.09% were classified as score 1 or 2 after vitrification. Nonviable staining of the oocyte was observed only in naked oocytes. Although these protocols demonstrate a reliable method for follicle collection and preliminary evidence for tools allowing the preservation of female gametes, further optimization is recommended. The demonstrated techniques are highly applicable to genebanking because they utilize material from unstimulated ovaries, as is regularly seen with tissues collected opportunistically from anestrus, ill, or old wildlife. This study was made possible by the cooperation and collection of tissues by the staff from Territory Wildlife Park, Northern Territory, and Tamara Keeley from Western Plains Zoo, New South Wales.

Molecular Simulations of Interacting Nanocrystals

We compute the potential of mean force for two gold nanocrystals capped by alkylthiols from atomistic simulations and show how variables such as temperature, capping molecule length, and the presence of solvent affect these interactions. Our main findings are (1) the equilibrium distance in vacuum always equals approximately 1.25 times the core diameter, (2) incomplete capping layers promote sintering, and (3) the presence of a good solvent results in purely repulsive interactions.

Brewster Angle Microscopy and PMIRRAS Study of DNA Interactions with BGTC, a Cationic Lipid Used for Gene Transfer

The lipid bis(guanidinium)-tris(2-aminoethyl)amine-cholesterol (BGTC) is a cationic cholesterol derivative bearing guanidinium polar headgroups which displays high transfection efficiency in vitro and in vivo when used alone or formulated as liposomes with the neutral colipid 1,2-di-[ cis-9-octadecenoyl]- sn-glycero-3-phosphoethanolamine (DOPE). Since transfection may be related to the structural and physicochemical properties of the self-assembled supramolecular lipid-DNA complexes, we used the Langmuir monolayer technique coupled with Brewster angle microscopy (BAM) and polarization modulation infrared reflection absorption spectroscopy (PMIRRAS) to investigate DNA-BGTC and DNA-BGTC/DOPE interactions at the air/water interface. We herein show that BGTC forms stable monolayers at the air/water interface. When DNA is injected into the subphase, it adsorbs to BGTC at 20 mN/m. Whatever the (+/-) charge ratio of the complexes used, defined as the ratio of positive charges of BGTC in the monolayer versus negative charges of DNA injected in the subphase, the DNA interacts with the cationic lipid and forms either an incomplete (no constituent in excess) or a complete (DNA in excess) monolayer of oriented double strands parallel to the lipid monolayer plan. We also show that, under a homogeneous BGTC/DOPE (3/2) monolayer at 20 mN/m, DNA adsorbs homogeneously to form an organized but incomplete layer whatever the charge ratio used (DNA in default or in excess). Compression beyond the collapse of these mixed DNA-BGTC/DOPE systems leads to the formation of dense DNA monolayers under an asymmetric lipid bilayer with a bottom layer of BGTC in contact with DNA and a top layer mainly constituted of DOPE. These results allow a better understanding of the mechanisms underlying the formation of the supramolecular BGTC-DNA complexes efficient for gene transfection.

Development and characterization of Fe ultrathin films on theSrTiO3(100) surface

The adsorption of Fe on the SrTiO3(100) surface at room temperature has been studied in ultrahigh vacuum by means of Augerelectron spectroscopy, low energy electron diffraction, electron energy loss spectroscopy,thermal desorption spectroscopy and work function measurements. The results show thatiron probably grows in the mode of successive incomplete layers. For coverages≥1.5 ML, ashort range 1 × 1 order appears and the deposited Fe overlayer develops in body-centred cubic structure with and crystallographic orientation . The results of the electron spectroscopies do not indicate any ironoxidation at the metal–oxide interface. Instead, an interaction between the Feadatoms gradually leads to the metallization of the Fe overlayer. Thus, theFe/SrTiO3(100) interfaceseems to be a rather abrupt metal–oxide interface, which presents a good thermal stability for annealingup to ∼800 K. In conclusion, this adsorption system looks ideal for free-standing ultrathinFe films and low-dimensional structures, useful for technological applications.

Development and Characterization of an Ultrathin Barium Oxide Film on a Surface Oxidized Ni(110) Substrate

In this work we develop an ultrathin barium oxide film by Ba adsorption on a pre‐oxidized Ni(110) surface, and characterize it by means of Auger electron spectroscopy, low energy electron diffraction and work function measurements. The results show that the Ba adatoms reduce the NiO surface oxide forming an amorphous and incomplete BaO layer. At higher coverages, the Ba adsorbate seems to approach the metallic state, with the BaO layer confined between NiO and the metallic Ba. The measured energy decreases of the atomic Ba(75 eV) and interatomic BaO(68 eV) low energy Auger transition lines are analyzed in terms of low core atomic levels, valence band and extra‐atomic relaxation energy changes.

Early Cellular and Stromal Responses in Regeneration Versus Repair of a Mammalian Bladder Using Autologous Cell and Biodegradable Scaffold Technologies

Internal organ regeneration holds promise for changing medical technology and decreasing organ shortages. Current medical treatment for internal organ failure is largely limited to organ transplantation. A construct composed of synthetic biopolymer with autologous cells has shown long-term clinical benefit in patients undergoing augmentation cystoplasty. However, to our knowledge early cellular and stromal events during bladder regeneration have not been elucidated. In situ cellular responses to 2 biopolymer implants, including a poly(lactic-co-glycolic acid) (Sigma-Aldrich) based biodegradable mesh scaffold with autologous urothelial and smooth muscle cells (construct) and a poly(lactic-co-glycolic acid) based biodegradable mesh scaffold alone without cells (scaffold), were compared in a canine model of augmentation cystoplasty. Healing events were correlated with urodynamic assessments. Construct implants regenerated baseline urodynamics as early as 4 months after implantation. Urodynamics following scaffold implantation failed to return to baseline by study termination at 9 months. Functional differences elicited by construct and scaffold implants correlated with structural differences in the neotissues. Construct stroma had greater vascularization with gently folded, interwoven connective tissue elements. Scaffold stroma was dense, haphazardly organized connective tissue. Urothelium regenerated in response to construct and scaffold implantation. However, only construct had normal stroma, well developed detrusor and abundant alpha-smooth muscle actin (Vector Laboratories, Burlingame, California) cell staining at early time points, leading to a structurally and functionally complete regenerated bladder wall at 9 months. Early cellular and stromal events distinguish healing processes that lead to bladder wall regeneration or repair. Construct implants containing cells elicit early healing processes that culminate with the regeneration of complete mucosal and muscular components, whereas the response to scaffold implantation is consistent with reparative healing, that is with mucosal growth but incomplete tissue layer development.

Androgen activity on the peripheral female genital target: ultrastructural study

There are still many areas in the field of female sexual physiopathologies that remain to be fully studied, among which are disturbances of the excitation phase, particularly the hemodynamics of the clitoral corpora cavernosa. Low levels of estrogens and vascular risks lie at the base of female sexual arousal disorders. The aim of our study was to investigate the ultrastructure of the clitoral cavernosal tissue in healthy women and those affected by metabolic and hormonal pathologies. Recent data show the presence of nitric oxide synthase in the clitoral tissue, suggesting that nitric oxide could be involved in the mechanisms of clitoral tumescence. Moreover, the presence of type 5 phosphodiesterase activity in clitoral tissue has been hypothesized. Informed consent was obtained from the 24 women enrolled in the study. Five were diabetic premenopausal women, and 8 were naturally post menopausal and 6 surgically post menopausal women affected by HSDD. They all underwent a micro-biopsy of the clitoral body by means of fine needle aspiration under total anesthesia during gynaecological operation for stress urinary incontinence. Five health women undergoing surgically procedures for benign gynaecological pathology were considered as control group. The tissue removed was fixed in Karnowski's liquid and underwent ultrastructural analysis with standard procedures. Histomorphometric studies have shown that there is a correlation between age and smooth muscle fibers of the clitoral corpora cavernosa due to an increase of connective tissue. In the clitoris there is also a correlation between large diameter thin-walled vessels and smooth muscle fibrocells(SMF), which make up the majority of the cellular elements of the concavity. In health premenopausal women there are extensive bundles of smooth muscle fibrocells SMF, seen both transversely and longitudinally; the SMF have regular borders, regular nuclei with dense chromatin and evident nucleoli. The cytoplasm includes contractile microfilaments and dense bodies. The cell borders do not have continuous basal membranes(BM) and electro-ionic junctions of the “tight” type. The SMF, in all pre menopause subjects, are isometric with regular borders, having a homogeneous distribution of the microfilaments and dense bodies. The basal membranes are regular with a constant thickness, rarely reduplicate. The blood vessels are thin-walled, made up of a flattened endothelial layer and by an incomplete layer of pericytes, a close association with the interstitial SMF is observed, which, with the pericytes, form tight junctions. The vascular lacunae are particularly interesting, having a single line of flattened epithelial cells with a cytoplasm relatively poor in organules, resting on continuous BM. The SMF have a direct relationship with the vascular lacunae, giving rise to an anatomical-functional complex comparable to that of the corpora cavernosa of the penis. In diabetic women, the SMF of the BM and the vascular lacunae are notably thickened. In natural post menopausal subjects the general arrangement is maintained, and only rarely is there a discrete thinning of the SMF, which can, in places, have an irregular border. The concavity, made up of isometric collagen fibers that can be poorly cohesive and moderately thickened in post menopausal subjects. In surgically postmenopausal women, clitoral tissue is reduced; the SMF have irregular distribution of the microfilaments and borders. The blood vessels are riduced, and the vascular lacunae have not relationship the SMF. Transdermic testosterone therapy of surgically postmenopausal women affected by HSDD seems to also act at the level of the clitoral tissue. In fact, the ultrastructure of the clitoral corpora cavernosa has features almost identical to those found in pre menopausal women. We hope the electronic microscopic study of the clitoral cavernosal tissue can give similar information to that recorded above, and can be used as an additional tool for the diagnosis, prognosis and therapeutic orientation of female sexual dysfunctions.

X-ray structural investigation of Co∕Cu granular multilayers with giant magnetoresistance

The effect of the reduction of the magnetic layer thickness on sample correlated roughness in Co∕Cu granular samples produced via the incomplete layer method has been investigated. When Co layer thickness is smaller than 3Å, they undergo a fragmentation process that modifies the expected sample magnetic and magnetoresistive properties. This behavior has been studied with anomalous x-ray diffuse intensity data collected in grazing incidence configuration by evaluating both roughness correlation lengths and the dynamic roughness exponent. The fragmentation process is found to promote conformal nanoscale roughness and to lower the giant magnetoresistance response of the system.

Studies of the adsorption of tetraphenylporphyrin molecules on graphite

Combined scanning tunneling microscopy, reflection electron energy loss spectroscopy and X-ray photoelectron studies have been performed in situ under ultra high vacuum condition, on tetraphenylporphyrin molecules (H 2TPP) vacuum sublimated on highly oriented pyrolitic graphite. The experimental studies were performed at room temperature, as a function of the amount of deposited porphyrins. The propensity of H 2TPP to self-assembly on the graphite surface could be detected after a threshold of deposited material. In this case tetraphenylporphyrin molecules arranged according to a quasi-hexagonal lattice separated from their nearest neighbours by a minimum distance of about 1 nm. The formation of an additional incomplete layer, at a slightly higher coverage, was also detected where the quasi-hexagonal symmetry is retained. Finally, subsequent tetraphenylporphyrins depositions gave molecular aggregates randomly distributed on the graphite surface with subsequent loss of order.

Artificial Nano-Scale Precipitates for Flux Pinning in YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-δ</sub> Thin Films and Coated Conductors

By controlling pulse number of laser ablation, we prepared a series of quasi-multilayers of YBa2Cu3O7-δ/M (M=incomplete oxide layer) namely 70×(40/n) (n = 2, 5, 10 and 20, pulse number of M) which were characterised with nano-scale precipitates. While the texture properties of Y123 inside qusi-multilayer hardly change, its Tc appeared much different depending on the doping level of M. X-ray θ-2θ scanning and pole figures indicated that the different growth-controlled precipitates occured inside Y123 films. In the case of M=YSZ (Yttria Stabilized Zirconia), nanosized perovskite precipitates of BaZrO3 formed as a result of solid state reaction of YSZ with Y123, leading to Tc obviously decreasing with increasing of n. In the case of M=Y2O3, however, Tc did not decrease so much at the studied range of n due to no solid state reaction mentioned above. Magneto-transport and field angular dependence showed that the critical current density in films with lower doping content (such as n = 2) was improved in large ranges of field and temperature, suggesting tailorable enhancement and anisotropy of flux pinning force.