AFM and Raman study of graphene deposited on silicon surfaces nanostructured by ion beam irradiation.

Nanoscale structures were produced on silicon surfaces by low-energy oxygen ion irradiation: periodic rippled or terraced patterns formed spontaneously, depending on the chosen combination of beam incidence angle and ion fluence. Atomic force microscopy image processing and analysis accurately described the obtained nanotopographies. Graphene monolayers grown by chemical vapour deposition were transferred onto the nanostructured silicon surfaces. The interfacial interaction between the textured surface and the deposited graphene governs the conformation of the thin carbon layer; the resulting different degree of regularity and conformality of the substrate-induced graphene corrugations was studied and it was related to the distinctive topographical features of the silicon nanostructures. Raman spectroscopy revealed specific features of the strain caused by the alternating suspension and contact with the underlying nanostructures and the consequent modulation of the silicon-graphene interaction. Lay Description In the field of nanosciences, nanotechnologies and advanced materials, it is pivotal to produce and integrate nanostructures in a controlled, cost-effective and possibly high-throughput manner. Currently, the surface nanopatterning by ion beam irradiation (IBI) is showing its potential in overcoming some of the limits that characterize the conventional lithographic techniques. IBI can produce self-organized and regular patterns of nanostructures, such as ripples, dots, and holes, having heights and lateral periodicities in a pre-defined range. The nanopatterns can develop over large surface areas of a broad class of materials and have been tested for different applications, e.g. microelectronic device fabrication, catalysis, nanoscale magnetism, surface-enhanced Raman scattering. Also, the ion-induced patterns allowed the control of physical properties such as wettability, reflectance, and photoluminescence. As a whole, this is a highly dynamic and continuously evolving field. Graphene was first obtained from bulk graphite by mechanical exfoliation; remarkable mechanical, thermal and optical properties came to light; they make graphene an ideal material for sensing. Also, the research on graphene paves the way for basic and applied studies on other ultrathin thickness materials, such as monolayer transition metal dichalcogenide or monolayer metal oxide, which also show peculiar properties as compared to their bulk version. Since graphene is a zero-gap semi-metal, a finite energy gap must be open to engineer graphene-based electronic devices. At this aim, researchers can take advantage of the mechanical properties of graphene, since its out-of-plane deformation can favourably modify its electronic structure. While the spontaneous, random self-folding of graphene to form wrinkles has thermodynamics reasons and is unavoidable above a certain material length, the interactions between graphene and substrates can generate, in principle, designed wrinkled structures. Therefore, a field of study has emerged, focused on the control and tuning of the geometry of graphene corrugations and their influence on specific physical and chemical properties. To the best of our knowledge, this work studies for the first time the geometry and strain in graphene wrinkles induced by silicon substrates that were suitably nanopatterned by ion beam irradiation.

Depth measurements of etch-pits in GaN with shape reconstruction from SEM images.

The method, which allows shape reconstruction by reading the intensity from the scanning electron microscopy image, is presented and discussed in details. The method is applied to read the morphology of etch-pits, which were formed on the GaN surface by etching in molten KOH-NaOH eutectic mixture to delineate dislocations. The etch-pit depth distributions are obtained and used to determine densities of pits related to screw, mixed or edge-type dislocations. The results are compared with atomic force microscopy.

[Severe hyponatremia during chemotherapy for small cell carcinoma]. / Hyponatrémie sévère sous chimiothérapie du carcinome à petites cellules.

INTRODUCTION: The small cell lung cancer (SCLC) is a rapidly progressive malignancy with a poor prognosis. Its chemosensitivity mandates prompt treatment. Hyponatremia occurs frequently in patients with small cell lung cancer due to the syndrome of inappropriate antidiuretic hormone (SIADH). We report a case of severe hyponatremia induced by chemotherapy that required management in intensive care. OBSERVATION: A 68-year-old patient was undergoing treatment for small cell cancer, invading the right lung. On the second day of the first cycle of treatment (cisplatine-vepeside), the patient became comatose and required transfer to an intensive care unit. The coma was due to severe hyponatremia (107 mmol/L) and improved with specific treatment. The patient had similar episodes on the second day of each chemotherapy treatment but with less and less severe clinical manifestations. Hyponatremia due to chemotherapy in SCLC is not commonly known; a relation between hyponatremia intensity and the tumor size is suspected. CONCLUSION: This clinical case highlights the possibility of severe hyponatremia during small cell lung cancer chemotherapy. Hyponatremia may be related to the reduction in tumor size. Monitoring of electrolytes on day 2 of chemotherapy is advised.

[The epidemiological aspects and prevalence of markers in those with viral hepatitis C in some population categories in 1994-1997 in Iasi County]. / Contributii la cunoasterea unor aspecte epidemiologice si a prevalentei posesorilor de markeri pentru virusul hepatitei C, în unele categorii populationale, în perioada 1994-1997, în judetul Iasi.

The results of the epidemiological, clinical and laboratory investigations, carried out in the 1994-1997 interval in the Iasi district, on various populational groups, to indicate the prevalence of the antibodies anti-HVC possessors are presented. In 3611 patients with clinical-epidemiological HCV diagnosis, it was recorded a prevalence of the anti-HCV antibodies (AcHCV) presence of 22.7%. Posttransfusional hepatitis, epidemiologically diagnosed in 205 hospitalised patients was attributed to HCV in 11.6% of the cases, and in 94 patients with neurological diseases, AcHCV were identified in 9.6%. The presence of AcHCV at 825 persons in medico-sanitary staff, from risk domains, has recorded a prevalence of 8.0%. In the January 1997-September 1997 interval, the investigation by IIIrd generation ELISA of 51,149 blood samples of donors from various areas indicated the presence of AcHCV with an interval average of 2.6%.

Leukocyte Gene Expression in Patients with Medication Refractory Depression before and after Treatment with ECT or Isoflurane Anesthesia: A Pilot Study.

Objective. To evaluate leukocyte gene expression for 9 selected genes (mRNAs) as biological markers in patients with medication refractory depression before and after treatment with ECT or isoflurane anesthesia (ISO). Methods. In a substudy of a nonrandomized open-label trial comparing effects of ECT to ISO therapy, blood samples were obtained before and after treatment from 22 patients with refractory depression, and leukocyte mRNA was assessed by quantitative PCR. Patients' mRNAs were also compared to 17 healthy controls. Results. Relative to controls, patients before treatment showed significantly higher IL10 and DBI and lower ADRA2A and ASIC3 mRNA (P < 0.025). Both ECT and ISO induced significant decreases after treatment in 4 genes: IL10, NR3C1, DRD4, and Sult1A1. After treatment, patients' DBI, ASIC3, and ADRA2A mRNA remained dysregulated. Conclusion. Significant differences from controls and/or significant changes after ECT or ISO treatment were observed for 7 of the 9 mRNAs studied. Decreased expression of 4 genes after effective treatment with either ECT or ISO suggests possible overlap of underlying mechanisms. Three genes showing dysregulation before and after treatment may be trait-like biomarkers of medication refractory depression. Gene expression for these patients has the potential to facilitate diagnosis, clarify pathophysiology, and identify potential biomarkers for treatment effects.

[Incidence of nosocomial infections at the Recovery Clinic of Iasi Hospital, in 2004-2005]. / Evaluarea incidentei infectiilor nosocomiale in Spitalul Clinic de Recuperare Iasi, in perioada 2004-2005.

OBJECTIVES: The nosocomial infections remain a major public health problem. The descriptive study has been performed on a sample of 37541 patients hospitalized in the sanitary during 2004-2005. The aim of the study was to evaluate the declared and real incidence of nosocomial infections, to evaluate the risk factors and the etiological agents involved in their occurrence. METHODS: The tracking of nosocomial infections (IN) was of an active nature. We have used the definition of clinical cases according to Ord. 994/2004; and have also taken into consideration the CDC criteria's of identifying these infections. RESULTS: The results show a low incidence of the IN (0.08%), under the values declared in the literature; among these, the urinary tract infections are on first place (48.38%), followed by the superficial surgical-site infections (29.03%), respiratory tract infections (11.13%) and skin infections (6.45%). The pathogen agents involved were Proteus spp. alone or in combination with Klebsiella spp., in the urinary tract infections; in the superficial surgical-site infections we found Staphylococcus and Proteus (33.34%).

[The relationship between zinc, copper and lipid metabolic indicators in adults]. / Studiul relatiei dintre zinc, cupru si indicatorii metabolismului lipidic la adulti.

The variation of the levels of serum zinc and copper was determined comparing with the variation of the lipidic indicators in a group of 169 adults from the general population. The subjects were divided by age and sex. Serum zinc declined with ageing, while serum copper increased. The lipidic indicators varied in direct correlation with serum copper and in indirect correlation with serum zinc excepting two cases: HDL-cholesterol values decreased in man 60 years older, and triglycerides values decreased lightly in men 41-60 years old.

[Viral hepatitis A as an occupational disease in the city of Iasi]. / Hepatita virala A, ca boala profesionala în municipiul Iasi.

OBJECTIVES: Few studies have been carried out to evaluate the role of hepatitis A virus (HAV) as an occupational hazard. Our analysis of data on occupational diseases in Romania showed that hepatitis ranks as one of the first among infectious occupational diseases. MATERIALS AND METHODS: Data on the role of hepatitis A, as occupational disease, were obtained by testing sera obtained from different occupational groups and compared results with the degree of immunity found among the normal population. An ELISA technique was used to determine the presence of each hepatitis marker (Murex kits for anti-HAV IgG). RESULTS: The ratio of prevalence in each subset compared to the general population was used to express relative risk. The results of our study show that hepatitis A is an important hazard to sewerage workers. In view of these results, it should be considered whether the occupational differences alone account for the divergence in immunity between the groups or whether socioeconomic aspects and differences in the standard of hygiene are also responsible for HAV infections.

[The incidence of HBsAg in different population groups of Moldavia in 1991 compared to 1973]. / Incidence de l'AgHBs dans différents groupes de population de Moldavie en 1991 par rapport à 1973.

AgHBs incidence in various population groups from the Iasi region was relatively high in 1991, ranging from 3.8% in blood donors to 75.0% in patients with severe acute virus hepatitis. As compared to the incidence values recorded in 1973, 18 years ago, in the population of the same territory, some mutations were observed, the most important being the more then threefold reduction of the AgHBs incidence in blood donors. In subjects with liver diseases and in risk groups, the frequency of AgHBs carriers maintains at a high level.

[Incidence of HBsAg among different population groups in Moldavia in 1991 compared with 1973]. / Incidence de l'AgHBs dans différents groupes de population de Moldavie en 1991 par rapport à 1973.

AgHBs incidence in various population groups from the Iassy region was relatively high in 1991, ranging from 3.8% in blood donors to 75.0% in patients with severe acute virus hepatitis. As compared to the incidence values recorded in 1973, 18 years ago, in the population of the same territory, some mutations were observed, the most important being the more then threefold reduction of the AgHBs incidence in blood donors. In subjects with liver diseases and in risk groups, the frequency of AgHBs carriers maintains at a high level.