A combined tactile and Raman probe for tissue characterization - Design considerations

Histopathology is the golden standard for cancer diagnosis and involves the characterization of tissue components. It is labour intensive and time consuming. We have earlier proposed a combined fibre-optic near-infrared Raman spectroscopy (NIR-RS) and tactile resonance method (TRM) probe for detecting positive surgical margins as a complement to interoperative histopathology. The aims of this study were to investigate the effects of attaching an RS probe inside a cylindrical TRM sensor and to investigate how laser-induced heating of the fibre-optic NIR-RS affected the temperature of the RS probe tip and an encasing TRM sensor. In addition, the possibility to perform fibre-optic NIR-RS in a well-lit environment was investigated. A small amount of rubber latex was preferable for attaching the thin RS probe inside the TRM sensor. The temperature rise of the TRM sensor due to a fibre-optic NIR-RS at 270 mW during 20 s was less than 2 degrees C. Fibre-optic NIR-RS was feasible in a dimmed bright environment using a small light shield and automatic subtraction of a pre-recorded contaminant spectrum. The results are promising for a combined probe for tissue characterization

Toe pressure and toe brachial index are predictive of cardiovascular mortality regardless of the most diseased arterial segment in symptomatic lower-extremity artery disease—A retrospective cohort study

Objective Although lower extremity arterial disease (LEAD) is most often multisegmental, the predominant disease location and risk factors differ between patients. Ankle-brachial index (ABI), toe-brachial index (TBI), and toe pressure (TP) are predictive of outcome in LEAD patients. Previously, we reported a classification method defining the most diseased arterial segment (MDAS); crural (CR), femoropopliteal (FP), or aortoiliac (AOI). Current study aimed to analyze the associations between MDAS, peripheral pressure measurements and cardiovascular mortality. Materials and methods We reviewed retrospectively 729 consecutive LEAD patients (Rutherford 2–6) who underwent digital subtraction angiography between January, 2009 to August, 2011 and had standardized peripheral pressure measurements. Results In Cox Regression analyses, cardiovascular mortality was associated with MDAS and noninvasive pressure indices as follows; MDAS AOI, TP 1.30 (HR 6.71, 95% CI 1.89–23.8), and MDAS CR, TP <30 mmHg (HR 4.26, 95% CI 2.19–8.27), TBI <0.25 (HR 7.71, 95% CI 1.86–32.9), and ABI <0.25 (HR 2.59, 95% CI 1.15–5.85). Conclusions Symptomatic LEAD appears to be multisegmental with severe infrapopliteal involvement. Because of this, TP and TBI are strongly predictive of cardiovascular mortality and they should be routinely measured despite the predominant disease location or clinical presentation.Peer reviewe

Brief isoflurane anesthesia regulates striatal AKT-GSK3 beta signaling and ameliorates motor deficits in a rat model of early-stage Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative movement disorder primarily affecting the nigrostriatal dopaminergic system. The link between heightened activity of glycogen synthase kinase 3 beta (GSK313) and neurodegenerative processes has encouraged investigation into the potential disease-modifying effects of novel GSK3 beta inhibitors in experimental models of PD. Therefore, the intriguing ability of several anesthetics to readily inhibit GSK3 beta within the cortex and hippocampus led us to investigate the effects of brief isoflurane anesthesia on striatal GSK3 beta signaling in nave rats and in a rat model of early-stage PD. Deep but brief (20-min) isoflurane anesthesia exposure increased the phosphorylation of GSK3 beta at the inhibitory Ser9 residue, and induced phosphorylation of AKT(Thr308) (protein kinase B; negative regulator of GSK3 beta) in the striatum of naive rats and rats with unilateral striatal 6-hydroxydopamine (6-OHDA) lesion. The 6-OHDA protocol produced gradual functional deficiency within the nigrostriatal pathway, reflected as a preference for using the limb ipsilateral to the lesioned striatum at 2 weeks post 6-OHDA. Interestingly, such motor impairment was not observed in animals exposed to four consecutive isoflurane treatments (20-min anesthesia every 48 h; treatments started 7 days after 6-OHDA delivery). However, isoflurane had no effect on striatal or nigral tyrosine hydroxylase (a marker of dopaminergic neurons) protein levels. This brief report provides promising results regarding the therapeutic potential and neurobiological mechanisms of anesthetics in experimental models of PD and guides development of novel disease-modifying therapies.Peer reviewe

Health and economic impacts of ozone ship-related air pollution in Portugal

Air pollution is the leading cause of the global burden of disease from the environment, entailing substantial economic consequences. International shipping is a significant source of NOx, SO2, CO and PM, which contributes to the increase in O3 levels that can cause known negative health impacts. Thus, this study aimed to estimate the health impacts of ozone ship-related air pollution in Portugal in 2015. To determine the health-related effects of this sector, shipping emissions were obtained from an Automatic Identification System based emission inventory using the Ship Traffic Emission Assessment Model (STEAM). Their contributions to SOMO35 (sum of ozone daily 8-h maximum means over 35 ppb in the calendar year, expressed in ppb per day) levels in Portugal were modelled using the EMEP/MSC-W chemistry transport model (simulations with and without shipping emissions). Log-linear functions based on WHO-HRAPIE relative risks for each health endpoint (all-cause and respiratory mortality, and cardiovascular and respiratory hospital admissions) were used to estimate the attributable fractions. Then, the excess burden of disease was calculated by multiplying the attributable fractions with the baseline incidence of each health endpoint and the population at LAU2 level. Costs associated with the health impacts were estimated as the product of the excess burden of disease and its unit health cost value. Shipping emissions contributed to an increase of 21% in the number of deaths for all-cause mortality and respiratory diseases, as well as hospital admissions for cardiovascular and respiratory diseases. A total external cost of around 180 (86-266) M€ a yr-1 was estimated for these health endpoints in 2015. These results show that O3-related air pollution from ships is a considerable problem affecting the Portuguese population. (c) 2019 WIT Pres

Growth mode-dependent ferromagnetic properties of palladium nanoclusters

This article has an erratum: DOI 10.1063/1.5078508Cluster deposited Pd films exhibit ferromagnetism in the temperature range from 1.8 to 400K. The magnetization properties are found to be dependent on the film thickness. The varying morphology of the resulting Pd film with respect to thickness suggests that cluster size, deposition energy, and substrate type are crucial for the resulting film magnetization. This is demonstrated by the characteristic ferromagnetic hysteresis with the temperature dependent saturation magnetization, remanence. and coercivity of palladium nanocluster aggregates. The temperature dependence of the saturation magnetization, remanence, and coercivity of Pd nanoclusters were measured using an ultra-high-sensitive magnetometer based on a superconducting quantum interference device, and the morphology of the samples was analyzed by tunneling electron microscopy. Published by AIP Publishing.Peer reviewe

On erbium lattice location in ion implanted Si0.75Ge0.25 alloy:Computer simulation of Rutherford backscattering/channeling

A high crystalline quality Si0.75Ge0.25 alloy layer grown by chemical vapor deposition was implanted with 70 keV Er+ ions to a fluence of 10(15) cm(-2) at temperature of 550 degreesC. The implantation was found to result in an Er depth distribution with 1 at. % maximum concentration 30 nm beneath the surface. The location of the erbium atoms in the host matrix lattice is derived through computer simulation of experimental axial channeling angular scans measured by in situ Rutherford backscattering/channeling spectrometry. Using computer code FLUX 7.7 it is shown that 60% of the implanted erbium atoms are located at ytterbium sites, 10% at tetrahedral sites, and the remainder are associated with random locations in the host matrix

Ion beam shaping and downsizing of nanostructures

We report a new approach for progressive and well-controlled downsizing of nanostructures below the 10 nm scale. Low energetic ion beam (Ar+) is used for gentle surface erosion, progressively shrinking the dimensions with ~ 1 nm accuracy. The method enables shaping of nanostructure geometry and polishing the surface. The process is clean room / high vacuum compatible being suitable for various applications. Apart from technological advantages, the method enables study of various size phenomena on the same sample between sessions of ion beam treatment.Comment: 14 pages, 6 figure

Impact of a nitrogen emission control area (NECA) on the future air quality and nitrogen deposition to seawater in the Baltic Sea region

Air pollution due to shipping is a serious concern for coastal regions in Europe. Shipping emissions of nitrogen oxides (NOx) in air over the Baltic Sea are of similar magnitude (330&thinsp;kt yr−1) as the combined land-based NOx emissions from Finland and Sweden in all emission sectors. Deposition of nitrogen compounds originating from shipping activities contribute to eutrophication of the Baltic Sea and coastal areas in the Baltic Sea region. For the North Sea and the Baltic Sea a nitrogen emission control area (NECA) will become effective in 2021; in accordance with the International Maritime Organization (IMO) target of reducing NOx emissions from ships. Future scenarios for 2040 were designed to study the effect of enforced and planned regulation of ship emissions and the fuel efficiency development on air quality and nitrogen deposition. The Community Multiscale Air Quality (CMAQ) model was used to simulate the current and future air quality situation. The meteorological fields, the emissions from ship traffic and the emissions from land-based sources were considered at a grid resolution of 4×4&thinsp;km2 for the Baltic Sea region in nested CMAQ simulations. Model simulations for the present-day (2012) air quality show that shipping emissions are the major contributor to atmospheric nitrogen dioxide (NO2) concentrations over the Baltic Sea. In the business-as-usual (BAU) scenario, with the introduction of the NECA, NOx emissions from ship traffic in the Baltic Sea are reduced by about 80&thinsp;% in 2040. An approximate linear relationship was found between ship emissions of NOx and the simulated levels of annual average NO2 over the Baltic Sea in the year 2040, when following different future shipping scenarios. The burden of fine particulate matter (PM2.5) over the Baltic Sea region is predicted to decrease by 35&thinsp;%–37&thinsp;% between 2012 and 2040. The reduction in PM2.5 is larger over sea, where it drops by 50&thinsp;%–60&thinsp;% along the main shipping routes, and is smaller over the coastal areas. The introduction of NECA is critical for reducing ship emissions of NOx to levels that are low enough to sustainably dampen ozone (O3) production in the Baltic Sea region. A second important effect of the NECA over the Baltic Sea region is the reduction in secondary formation of particulate nitrate. This lowers the ship-related PM2.5 by 72&thinsp;% in 2040 compared to the present day, while it is reduced by only 48&thinsp;% without implementation of the NECA. The effect of a lower fuel efficiency development on the absolute ship contribution of air pollutants is limited. Still, the annual mean ship contributions in 2040 to NO2, sulfur dioxide and PM2.5 and daily maximum O3 are significantly higher if a slower fuel efficiency development is assumed. Nitrogen deposition to the seawater of the Baltic Sea decreases on average by 40&thinsp;%–44&thinsp;% between 2012 and 2040 in the simulations. The effect of the NECA on nitrogen deposition is most significant in the western part of the Baltic Sea. It will be important to closely monitor compliance of individual ships with the enforced and planned emission regulations.</p

Surface Enhanced Second Harmonic Generation from Macrocycle, Catenane, and Rotaxane Thin Films: Experiments and Theory

Surface enhanced second harmonic generation (SE SHG) experiments on molecular structures, macrocycles, catenanes, and rotaxanes, deposited as monolayers and multilayers by vacuum sublimation on silver, are reported. The measurements show that the molecules form ordered thin films, where the highest degree of order is observed in the case of macrocycle monolayers and the lowest in the case of rotaxane multilayers. The second harmonic generation activity is interpreted in terms of electric field induced second harmonic (EFISH) generation where the electric field is created by the substrate silver atoms. The measured second order nonlinear optical susceptibility for a rotaxane thin film is compared with that obtained by considering only EFISH contribution to SHG intensity. The electric field on the surface of a silver layer is calculated by using the Delphi4 program for structures obtained with TINKER molecular mechanics/dynamics simulations. An excellent agreement is observed between the calculated and the measured SHG susceptibilities.