Granular vortex spin-torque nano oscillator for reservoir computing.

In this paper, we investigate the granularity in the free layer of the magnetic tunnel junctions (MTJ) and its potential to function as a reservoir for reservoir computing where grains act as oscillatory neurons while the device is in the vortex state. The input of the reservoir is applied in the form of a magnetic field which can pin the vortex core into different grains of the device in the magnetic vortex state. The oscillation frequency and MTJ resistance vary across different grains in a non-linear fashion making them great candidates to be served as the reservoir's outputs for classification objectives. Hence, we propose an experimentally validated area-efficient single granular vortex spin-torque nano oscillator (GV-STNO) device in which pinning sites work as random reservoirs that can emulate neuronal functions. We harness the nonlinear oscillation frequency and resistance exhibited by the vortex core granular pinning of the GV-STNO reservoir computing system to demonstrate waveform classification.

Room temperature two terminal tunnel magnetoresistance in a lateral graphene transistor.

We investigate the behavior of both pure spin and spin-polarized currents measured with four-probe non-local and two probe local configurations up to room temperature and under an external gate voltage in a lateral graphene transistor, produced using a standard large-scale microfabrication process. The high spin diffusion length of pristine graphene in the channel, measured both directly and by the Hanle effect, and the tuning of the relationship between the electrode resistance areas present in the device architecture allowed us to observe local tunnel magnetoresistance at room temperature, a new finding for this type of device. The results also indicate that while pure spin currents are less sensitive to temperature variations, spin-polarized current switching by an external voltage is more efficient, due to a combination of the Rashba effect and a change in carrier mobility by a Fermi level shift.

Exposure to acute electromagnetic radiation of mobile phone exposure range alters transiently skin homeostasis of a model of pigmented reconstructed epidermis.

Exposure to electromagnetic radiations (EMR) produced by mobile phone concerns half the world's population and raises the problem of their impact on human health. In this study, we looked at the effects of mobile phone exposure (GSM basic, 900 MHz, SAR 2 mW g(-1) , 6 h) on a model of pigmented skin. We have analysed the expression and localization of various markers of keratinocyte and melanocyte differentiation 2, 6, 18 and 24 h after EMR exposure of reconstructed epidermis containing either only keratinocytes or a combination of keratinocytes and melanocytes grown on dead de-epidermized dermis, using histology, immunohistochemistry and Western blot. No changes were found in epidermal architecture, localization of epidermal markers, presence of apoptotic cells and the induction of p53 in both types of epidermis (with or without melanocytes) after exposure to EMR. In pigmented reconstructs, no change in the location and dendricity of melanocytes and in melanin transfer to neighbouring keratinocytes was detected after EMR exposure. Loricrin, cytokeratin 14 were significantly decreased at 6 h. The level of all markers increased at 24 h as compared to 6 h post-EMR exposure, associated with a significant decrease of the 20S proteasome activity. Our data indicate that exposure to 900 MHz frequency induces a transient alteration of epidermal homoeostasis, which may alter the protective capacity of the skin against external factors. Presence or absence of melanocytes did not modify the behaviour of reconstructs after EMR exposure.

Ultrastructural assessments of the melanosome distribution patterns and pigmentation features in human epidermal cells after UV irradiation and kojic acid treatment.

It is well-known that skin pigmentation depends, among others, on number, aggregation and distribution of melanosomes in the epidermis. Here we describe a correlative microscopy-based ultrastructural approach that investigates the spatial distribution and pigmentation features of the melanosomes within melanocytes and keratinocytes. Data obtained from control skin, ultraviolet (UV)-stimulated tissue and kojic acid-treated UV-irradiated explants are compared. We introduce original parameters for the evaluation of the aggregation and pigmentation features of the melanosomes: the aggregation and pigmentation indexes. The aggregation index evaluates the presence of clustered melanosomes when the pigmentation index expresses the electron-density level of the pigment granules. The present study demonstrates that the last parameters clearly express histological effects induced by UVB irradiation. Results indicate that UV light did not change the number of melanosomes within either melanocytes or keratinocytes, but it definitely modified the distribution patterns of the pigment granules in both cell types. It also enhanced the pigmentation state of the epidermal cells. Moreover, statistical analysis concerning keratinocytes discloses a significant decrease in the mean pigmentation index when explants exposed to UV light were treated with kojic acid. Obviously, the present numerical findings point out the relevance of the introduced parameters to characterize the pigmentation state of skin.

Molecular basis of the interactions between herpes simplex viruses and HIV-1.

Herpes simplex virus types 1 and 2 (HSV-1 and -2) are two of the major opportunistic agents involved in the pathogenesis of AIDS, which is caused by human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2). A body of evidence suggests that they can also act as co-factors by interacting with HIV-1, thereby influencing disease progression. Indeed, the HIV-1 life cycle can be affected by HSV at different levels of interaction, both in vitro and in vivo: (i) transactivation of the HIV-1 long terminal repeat can be mediated, probably through different pathways, by HSV-1-infected cell protein (ICP)0, ICP4, ICP27 and US11 gene products; the HSV-1 transactivator viral protein 16 is not able to transactivate the long terminal repeat; (ii) cytokine release and antigen presentation from HSV-infected cells are both able to stimulate HIV-1 expression; (iii) Pseudotyping of the HIV-1 core particle with HSV-1 envelope glycoproteins can expand HIV-1 tropism to new cell types. Moreover, in vivo studies report that aciclovir treatment can produce a survival benefit in HIV-1-infected patients and that recurrent genital herpes appears to be linked to HIV-1 transmission by both boosting plasma retroviral load and providing a portal of entry and exit for HIV-1.

Effects of choline-esterase inhibitor in experimental acute pancreatitis in rats. Preliminary results.

Choline-esterase inhibitor (C1-INH), a regulatory alpha-glycoprotein, was administered at different dosages and intervals to rats with induced acute pancreatitis. When compared to controls, treated rats showed no significant differences in the severity of histopathological lesions, such as edema and single cell necrosis. On the other hand, both mortality and extent of massive necrosis were significantly affected by C1-INH administration regardless of the dosages.

Papanicolau smear chances to be diagnostic for cervical squamous intraepithelial lesions (SIL) with or without detectable HPV DNA at in situ hybridization analysis.

The Authors have correlated 39 cervical diagnostic biopsies for squamous intraepithelial lesions (SILs) with correspective Papanicolau smears (PS), with relation to the presence or the absence of HPV of oncogenic type (HPV-one) detected by in situ hybridization (ISH). Agreement between cytological and histological diagnosis was present in 14 of 16 cases with detectable HPV-one and only in 12 of 23 cases without detectable HPV-one at ISH. The importance of the HPV type in the SILs with relation to the diagnostic accuracy of Papanicolaou smears has been discussed.

Early graft injuries after pancreatic transplantation in syngeneic rats. Cytoprotective effects of gabexate-mesilate.

Failures in experimental and human pancreatic transplantation are mainly attributable to rejection, graft thrombosis, and technical problems. There are, however, problems related to other causes, such as preservation injuries, which we found to exhibit, at least within the first 6 h, the same histological patterns seen in experimental acute pancreatitis. We performed pancreatic transplantation in 110 syngeneic rats under different preservation techniques and administration of gabexate mesilate, a synthetic protease inhibitor. The results showed that antiprotease treatment reduces graft preservation injuries significantly.

Pancreaticoduodenal graft in the rat: an original microsurgical technique.

The authors describe an original surgical technique for pancreatic transplantation carried out on an experimental rat model which duplicates as closely as possible the anatomic-functional situation of a pancreatic graft in man (one arterovenous vascular peduncle with one functioning kidney only). The technique entails a microanastomosis between the mesenteric artery and the portal vein of the donor organ with the left renal artery and vein of the recipient. This method appears to be technically encouraging and particularly useful in studying the early phases of ischemic graft injuries, a field in which the authors are particularly interested.

[Use of microsystems for the identification of Enterbacteria in the microbiological laboratory: comments on technics and identification procedures]. / L'impiergo di microsistemi per la identificazione degli Enterobatteri nel laboratorio di indagini microbiologiche: rilievi sulle tecniche e sugli schemi di identificazione.

The Authors have pointed out the characteristics of 3 miniaturized systems for the enterobacteria identification: Enterotube, API 20 E, Minitek. They particularly described the accuracy in biochemical reactions and the agreement between the mini-systems identifications and conventional (routine media) identifications (and reactions); all the identification errors made with micro-systems are reported and explaned. Nine atypical strains, which give some identification problems, are reported with all the biochemical profils. The more typical characteristics of the 3 miniaturized systems are summarized in a table.

[Isolating and enriching broths of Salmonellae]. / I brodi di arricchimento e di isolamento delle salmonelle. Indagine comparativa

The Authors have tested in 3 isolating and enriching broths some Salmonellae; the broths are available commercially (MUELLER-KAUFMANN broth, LEIFSON broth and HAJNA GN broth) and they tested their inhibitory capacity (concerning the growth of intestinal saprophyte flora) and their enriching capacities with regard to the various types of Salmonellae also. The method used consists in an exact evaluation of the increase percentage of the germs which were put to incubate in the broths at 37 degree C for 6, 15 and 24 hours. On completing the tests it is clearly evident that the MUELLER-KAUFMANN and the LEIFSON broths are far superior to the HAJNA broth (which proved to be not very activated in decreasing the growth of the intestinal saprophytes). At the same time, it should be pointed out the opportuneness of effecting the re-transplantation from the Salmonellae broths only after 24 hours, in order to permit a more abundant growth of the Salmonellae (and therefore easier and surer isolation) without, at the same time, observing an appreciable interference by the common intestinal saprophytes.