Erbium-doped silicon nanocrystals grown by r.f. sputtering method: competition between oxygen and silicon to get erbium

Erbium doped micro- and nanocrystalline silicon thin films have been deposited by co-sputtering of Er and Si. Films with different crystallinity, crystallite size, hydrogen and oxygen content have been obtained in order to investigate the effect of the microstructure and composition of matrix on the near IR range at 1.54 µm Er-related photoluminescence (PL) properties. The correlation between the optical properties and microstructural parameters of the films is investigated using spectroscopic ellipsometry. It is found that the luminescent properties of these composite films can be understood on the basis of the ellipsometric analysis that reveals the films heterogeneous structure, and that Er-related PL dominates in films with 1-3 nm sized Si nanocrystals embedded in a-Si:H.INTAS Project #03-51-6486Fundação para a Ciência e a Tecnologia Project POCTI/CTM/39395/200

Presence and distribution of the brown bear (Ursus arctos) in Friuli Venezia Giulia, from 2004 to 2011, through the non-invasive genetic monitoring ad conservation implications

After having disappeared at the beginning of 1900, the brown bear has started in a late 1960s a slow process of recolonization of the north-eastern Alps, through an expansion of Dinaric population. At the end of the 1990s the University of Udine began the occasional monitoring of the species and from 2004 non-invasive genetic monitoring became systematic. In the last 8 years 217 hair traps have been activated in the region to monitore: Natisone Valleys, the Julian and Carnic Alps and Prealps. Twenty-six hair traps were monitored in all years, whereas 40 were observed only in 2004, 2007 and 2011. The 26 hair traps constantly monitored from 2004 to 2011 showed 17% of average success of hair’s collecting (brown bear samples collected/day control: BBSD). The 40 hair traps, monitored in the window period, showed 12% of BBSD. The BBSD value varied in relation to both season (highest in spring) and year, with a dramatic decline from 2008, and interaction between year and area. From 2004, 13 genotypes, through systematic hair traps monitoring, were identified, while only 2 genotypes were sampled opportunistically. It was observed a high turnover of the genotypes: only 7 genotypes were sampled for more than 2 years (47% of total), 4 genotypes (27% of the total) were sampled for 3 years or more. The annual attendance of bear have been constant from 2004 to 2007, with 5-6 genotypes present every year. In the period between 2008 and 2010 there was a drastic decrease in the successful collection at the hair traps, with and average of 1-2 animals genotyped per year. However, opportunistic samples have increased in the recent times, probably due to the arrivals of 3 genotypes from Trentino (KJ2G2 in 2009 and DG2 and MJ4 in 2011). The year 2011 showed a further increase in the presence of bears with 5 animals genotyped in Friuli Venezia Giulia. Three of these animals belonged to the Slovenian population, while the other 2 genotypes were from the Trentino population. The results seem to confirm the exchange of some individuals between the Dinaric and central alpine population. As an example, the dinaric bear M5 was genotyped in Friuli Venezia Giulia in 2008 and then sampled in 2009 and captured in 2010 in Trentino and finally slot in Slovenia in 2011. The distribution in the alpine and prealpine areas has changed year by year: from the 2004 to 2007 the Natisone Valley and the Julian prealpine areas along the border with Slovenia were the areas more used, whilst from 2009 there was an apparent higher presence of bears in the Carnian Prealps and Alps, and in the Julian Alps. This shift could be due to human disturbance (i.e hunting management), control of the species carried out in neighbouring Slovenia, with a decreasing of immigrant from dinaric populations, and new immigration of bears from the central Alps. The present work has highlighted the necessity for a trans-regional and cross-border management of the species, especially in consideration to the population control applied in Slovenia, which seem to limit the Dinaric population expansion in the Alps, and furthermore the philopatry behaviour of bear females, which implies the absence of females in Friuli Venezia Giulia and induces a movement bach to Slovenia (at least 3 bears genotyped in Italy were shot in Slovenia). All these elements seem to exert important limitations to the consolidation and stabilization of the population of brown bears in north-eastern Alps. From the methodological point of view the protocol of systematic non-invasive genetic monitoring, shared at the trans-regional and trans-boundary level, is fundamental to monitore the dynamics and distribution of bear; the protocol should follow a systematic experimental design and should be integrated with a efficient opportunistic data collection

The structure and photoluminescence of erbium-doped nanocrystalline silicon thin films produced by reactive magnetron sputtering

We have produced and studied undoped and erbium-doped nanocrystalline silicon thin films in order to evaluate the erbium influence on the film microstructure and how this correlates with the photoluminescence properties. Films were grown by reactive RF sputtering. For the doped films metallic erbium was added to the c-Si target. The structural parameters and the chemical composition of the different samples were investigated by X-ray in the grazing incidence geometry, Raman spectroscopy, ellipsometry and Rutherford Back Scattering. The effect of the nc-Si/SiOx matrix ,i.e., nc-Si volume fraction and the presence of SiO and/or SiO2 phases, on the erbium photoluminescence efficiency is discussed.(undefined

Spectroscopic ellipsometry study of the layer structure and impurity content in Er-doped nanocrystalline silicon thin films

Er doped nc-Si thin films have been investigated by spectroscopic ellipsometry (SE). The optical response of Er ions in a nc-Si/SiO matrix has been determined by SE, and it has been used to detect Er contents as low as 0.2 at%. The complex layered nanostructure of nc-Si:Er:O has been resolved and it has been found that it is strongly influenced by the Er-doping and the oxygen in-depth distribution profile. SE results are discussed in comparison with data obtained by the standard methods of the X-ray diffraction, Rutherford backscattering and Raman spectroscopy

Synthesis and Biological Evaluation of Dantrolene-Like Hydrazide and Hydrazone Analogues as Multitarget Agents for Neurodegenerative Diseases

Dantrolene, a drug used for the management of malignant hyperthermia, had been recently evaluated for prospective repurposing as multitarget agent for neurodegenerative syndromes, including Alzheimer's disease (AD). Herein, twenty-one dantrolene-like hydrazide and hydrazone analogues were synthesized with the aim of exploring structure-activity relationships (SARs) for the inhibition of human monoamine oxidases (MAOs) and acetylcholinesterase (AChE), two well-established target enzymes for anti-AD drugs. With few exceptions, the newly synthesized compounds exhibited selectivity toward MAO B over either MAO A or AChE, with the secondary aldimine 9 and phenylhydrazone 20 attaining IC50 values of 0.68 and 0.81 μM, respectively. While no general SAR trend was observed with lipophilicity descriptors, a molecular simplification strategy allowed the main pharmacophore features to be identified, which are responsible for the inhibitory activity toward MAO B. Finally, further in vitro investigations revealed cell protection from oxidative insult and activation of carnitine/acylcarnitine carrier as concomitant biological activities responsible for neuroprotection by hits 9 and 20 and other promising compounds in the examined series

Role of peripheral quantitative computed tomography in identifying disuse osteoporosis in paraplegia

Objective: Disuse osteoporosis is a major long-term health consequence of spinal cord injury (SCI) that still needs to be addressed. Its management in SCI should begin with accurate diagnosis, followed by targeted treatments in the most vulnerable subgroups. We present data quantifying disuse osteoporosis in a cross-section of the Scottish paraplegic population to identify subgroups with lowest bone mineral density (BMD). Materials and Methods: Forty-seven people with chronic SCI at levels T2-L2 were scanned using peripheral Quantitative Computed Tomography (pQCT) at four tibial sites and two femoral sites, at the Queen Elizabeth National Spinal Injuries Unit, Glasgow (U.K.). At the distal epiphyses, trabecular BMD (BMDtrab), total BMD, total bone cross-sectional area (CSA), and bone mineral content (BMC) were determined. In the diaphyses, cortical BMD, total bone CSA, cortical CSA, and BMC were calculated. Bone, muscle and fat CSAs were estimated in the lower leg and thigh. Results: BMDtrab decreased exponentially with time since injury, at different rates in the tibia and femur. At most sites, female paraplegics had significantly lower BMC, total bone CSA and muscle CSA than male paraplegics. Subjects with lumbar SCI tended to have lower bone values and smaller muscle CSAs than in thoracic SCI. Conclusion: At the distal epiphyses of the tibia and femur, there is generally a rapid and extensive reduction in BMDtrab after SCI. Female subjects, and those with lumbar SCI, tend to have lower bone values than males or those with thoracic SCI, respectively. Keywords: Bone loss, osteoporosis, paraplegia, peripheral Quantitative Computed Tomography, spinal cord injur

CT-GUIDED TRANSTHORACIC NEEDLE BIOPSY: ADVANTEGES IN HISTOPATHOLOGICAL AND MOLECULAR TESTS

Aim: The present study aimed to demonstrate that computed tomography-guided transthoracic needle biopsy (TTNB) is a safe procedure that gives a more accurate pre-operative tissue diagnosis for peripheral lung nodules than transthoracic needle aspiration, obtaining suitable samples for molecular test in lung adenocarcinomas. Patients and methods: Between December 2016 and March 2018 at Thoracic Surgery Department of the University of Palermo - Policlinico Paolo Giaccone Hospital, TTNB was performed in 42 patients with computed tomography-detected peripheral lung nodules > 10 mm, using 16-18 -Gauge tru-Cut needles. Results: With TTNB, we have estimated an accuracy for tissue diagnosis of 97,6%. At the molecular test, EGFR overexpression and ALK mutation resulted positive for 12/23 patients with lung adenocarcinoma. Conclusion: TTNB has showed a low rate of complications and it is adoptable as standard diagnostic procedure for peripheral lung nodules

Measuring the implementation of a group-based Lifestyle-integrated Functional Exercise (Mi-LiFE) intervention delivered in primary care for older adults aged 75 years or older: a pilot feasibility study protocol

Background Declines in function and quality of life, and an increased risk of cardiovascular events, falls, and fractures occur with aging and may be amenable to exercise intervention. Primary care is an ideal setting for identifying older adults in need of exercise intervention. However, a cost-effective, generalizable model of chronic disease management using exercise in a real-world setting remains elusive. Our objective is to measure the feasibility, potential effectiveness, and implementation of an evidence-based Lifestyle-integrated Functional strength and balance Exercise (LiFE) intervention adapted as a group-based format (Mi-LiFE) for primary care to promote increased physical activity levels in older adults aged 75 years or older. We hypothesize that the intervention will be feasible without modification if ≥30 individuals are recruited over 6 months, ≥75 % of our sample is retained, and ≥50 % of our sample complete exercises ≥3 days per week. Methods/design A pre-post pilot study design will be used to evaluate feasibility, potential effectiveness, and implementation outcomes over a 6-month period in physically inactive older adults ≥75 years recruited from a local family health team practice. The reach, effectiveness, adoption, implementation, and maintenance (RE-AIM) framework will be applied to evaluate the public health effects of the intervention including outcomes both at the individual and organizational levels. A physical therapist will teach participants how to integrate strength and balance activities into their daily lives over one individual and four group-based sessions, and two phone calls. Assessments will be completed at baseline and 6 months. Feasibility outcomes include recruitment over 6 months, retention at follow-up, and adherence measured by activity diaries. Change in patient-centered and implementation outcomes that will be evaluated include physical activity levels using accelerometers and International Physical Activity Questionnaire, physical performance using short physical performance battery, quality of life using EQ5D questionnaire, falls and harms using daily calendar diaries and self-report, fidelity using descriptive feedback, barriers and facilitators to implementation using thematic content analysis, and process outcomes. Discussion The feasibility and implementation of the Mi-LiFE intervention in primary care for older adults will be evaluated, as well as the effects of the intervention on secondary outcomes. If the intervention appears feasible, we will use the resultant information to design a larger trial.The Chronic Disease Prevention Initiative seed grant (https://uwaterloo.ca/propel/waterloo-chronic-disease-prevention-initiative) from the Propel Centre for Population Health Impact at the University of Waterloo funded the Mi-LiFE study