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Currently, simulations of the induced currents in the brain produced by transcranial magnetic stimulation (TMS) are used to elucidate the regions reached by stimuli. However, models commonly found in the literature are too general and neglect imperfections in the windings. Aiming to predict the stimulation sites in patients requires precise modeling of the electric field (E-field), and a proper calibration to adequate to the empirical data of the particular coil employed. Furthermore, most fabricators do not provide precise information about the coil geometries, and even using X-ray images may lead to subjective interpretations. We measured the three components of the vector magnetic field induced by a TMS figure-8 coil with spatial resolutions of up to 1 mm. Starting from a computerized tomography-based coil model, we applied a multivariate optimization algorithm to automatically modify the original model and obtain one that optimally fits the measurements. Differences between models were assessed in a human brain mesh using the finite-elements method showing up to 6% variations in the E-field magnitude. Our calibrated model could increase the precision of the estimated E-field induced in the brain during TMS, enhance the accuracy of delivered stimulation during functional brain mapping, and improve dosimetry for repetitive TMS. Graphical Abstract Geometrical model of TMS coil based on TAC images is optimally deformed to match magnetic field measurements. The calibrated model's induced electric field in the brain differs from the original. [ABSTRACT FROM AUTHOR]

Abstract The bacterial photosynthetic reaction centre (RC) is a membrane spanning protein that, upon illumination, promotes the reduction of a ubiquinone molecule withdrawing electrons from cytochrome c 2. This photo-activated reaction has been often exploited, in suitably designed photoelectrochemical cells, to generate photocurrents sustained by the reduction at the working electrode of the photo-oxidized electron donor or by the oxidation of the electron acceptor. In this work we have explored in more detail the factors affecting the photocurrent generation in commercially available screen-printed electrochemical cells containing an electrolyte solution where RC proteins and suitable mediators are solubilized. In particular, the role of the applied potential and the influence of concentration and structure of acceptor and donor molecules have been assessed. We show that efficient generation of cathodic photocurrents in a three electrode configuration occurs at an applied potential of 0.0 V versus quasi-ref Ag (the open circuit potential of the system measured in the dark) in presence of ferrocenemethanol and decylubiquinone, which proved to guarantee high performances as electron donor and acceptor respectively. Moreover, we employed a set of differential equations, describing reaction and diffusion processes, for modelling with high accuracy the chronoamperometry profiles recorded at variable RC concentrations. This model allowed us to estimate the kinetic parameters relevant to the chemical and electrochemical reactions triggered by light and to get a snapshot of the electrolyte composition in the bulk and electrode surroundings at different times from the light exposure. The characteristic time course of the photocurrent, showing a fast rise to a peak value followed by a slower decay, has been therefore explained as the result of the strict interconnection between the dynamical processes involved. Graphical abstract Image 1 Highlights • A photoelectrochemical transduction system based on solubilized RCs is presented. • Ferrocenemethanol and decylubiquinone act as efficient redox mediators for RC wiring. • The WE acts as photocathode by applying the OCP measured in the dark. • The intensity and the time course of the photocurrent depend on the RC concentration. • The photochronoamperometric profiles are predicted by a suitable computational model. [ABSTRACT FROM AUTHOR]

The development of an amperometric biosensor for herbicide detection, using bacterial reaction centers (RC) as biorecognition element, is presented. RC immobilization on gold screen printed electrodes was achieved by LIFT, a powerful physisorption-based immobilization technique that enhances the intimate contact between the protein and the electrode surface. As a result, stable photocurrents driven by direct electron transfer at the donor side were observed, both in the presence and in the absence of a quinone substrate in solution. The addition of quinone UQ 0 increased the photocurrents, while the UQ 0 -free system showed higher sensitivity to the herbicide terbutryn, a model inhibitor, acting as photocurrent attenuator. In spite of its simple design, the performances achieved by our mediatorless device are comparable or superior to those reported for analogous RC-based photoelectrochemical cells, in terms of both terbutryn sensing and photocurrent generation. [ABSTRACT FROM AUTHOR]

Reduced-intensity conditioning (RIC) regimens in cord blood transplant (CBT) are increasingly utilized for older patients and those with comorbidities. However, the optimal conditioning regimen has not yet been established and remains a significant challenge of this therapeutic approach. Antithymocyte globulin (ATG) has been incorporated into conditioning regimens in order to decrease the risk of graft failure; however, use of ATG is often associated with infusion reactions and risk of post-transplant complications. We report the results of a non-ATG-containing RIC regimen, where patients received 2 Gy TBI unless they were considered to be at higher risk of graft failure, in which case they received 3 Gy of TBI. Thirty patients underwent CBT using this protocol for high-risk hematological malignancies. There was only one case of secondary and no cases of primary graft failure. At 1 year, estimates of non-relapse mortality, OS and PFS were 29%, 53% and 45%, respectively. The cumulative incidences of grade III-IV acute and chronic GVHD were 14% and 18%, respectively. In summary, the results of this study demonstrate that this non-ATG-containing conditioning regimen provides a low incidence of graft failure without increasing regimen-related toxicity. [ABSTRACT FROM AUTHOR]

This paper describes the assessment of a free and open-source software tool for power system analysis and modeling, namely Power System Analysis Toolbox (PSAT). PSAT is currently used in several universities for undergraduate and graduate courses and research. Several applications of PSAT as an educational and research tool are discussed here. The paper also describes the PSAT Web forum, which provides support to students and researchers all around the world. Finally, the paper presents and discusses the results of a survey on PSAT filled out by the members of the PSAT forum and PSAT users. [ABSTRACT FROM AUTHOR]

Immunotherapy for solid cancers, such as oesophageal adenocarcinoma (OAC), is generally hampered by an unfavourable immunological tumour microenvironment. This prompted us to investigate the nature of the OAC environment. Biopsies of tumour and normal control tissues were collected from 17 OAC patients, and investigated using fluorescent immunohistochemistry (IHC) for the expression of cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF), transforming growth factor-β, indoleamine 2–3 dioxygenase, CXCL3 and CXCR1, and for measuring a panel of cytokines by cytometric bead array (CBA), and for Granzyme B (GrB), Perforin and PI9 detection by semi-quantitative PCR (QPCR). IHC showed that expression of all the above-mentioned factors is upregulated in 80–93% of the tumours. By QPCR, the cytokine interleukin (IL)-8 was significantly upregulated in tumour samples ( P < 0.05). IL-6, IL-10, GrB and Perforin did not show any significant difference between normal and tumour samples, whereas PI9 levels were significantly higher in normal when compared with the tumour samples. CBA confirmed upregulation of IL-8 and show upregulation of IL-1β in the tumours ( P < 0.05). Regarding IL-6 and interferon (IFN)-γ, no significant differences were observed between normal and tumour tissues. The OAC microenvironment is characterized by a lack of cytokines and factors that normally would enhance anti-cancer responses, such as IFN-γ and GrB, and by a high expression of several immuno-suppressive factors, such as COX-2, VEGF and IL-8. For future improvement of treatment efficacy of OAC patients, it will be of importance to combine immunotherapy with immune-modulating agents. [ABSTRACT FROM AUTHOR]

This paper addresses reactive power adequacy problems in distribution networks that include a significant number of distributed energy resources. The voltage profile of the distribution network is analyzed under increasing amounts of generation provided by the distributed energy resources. Both static and dynamic voltage disruption phenomena resulting from increasing distributed generation are described and the need for remedial actions identified. Different reactive power control schemes are then proposed to keep both an appropriate voltage profile and an appropriate voltage stability margin. Finally, an economic appraisal of remedial actions is carried out and the responsible parties identified. Results from a realistic case study are presented and discussed. Conclusions are duly drawn. [ABSTRACT FROM AUTHOR]

Ten samples of commercially Italian red wines were analyzed in order to determine the phenolic content. Variations in wine types are largely due to differences in concentration and composition of these compounds. Polyphenolic compounds are a large and complex group of substances which constitute one of the most important quality parameters of wine. These constituents of red wine contribute to organoleptic characteristics and to antioxidant and anti-inflammatory properties. Moderate wine consumption is associated with several beneficial physiological effects, which include anticancer activities, inhibition of platelet aggregation, and inhibition of LDL oxidation which constitutes the initial stage of the pathogenesis of arteriosclerosis. For the analysis, reversed-phase high performance liquid chromatography (HPLC) method coupled with UV-Vis detection was used. The method uses a gradient elution to identify nine biologically active phenolic constituents: catechin; epicatechin; trans- and cis-resveratrol; gallic, chlorogenic and caffeic acid; rutin and quercetin in red wine samples. The samples are injected directly without any pretreatment. The method is simple, fast, not expensive and shows good linearity for all constituents, and the detection limits ranged from 0.3-1.6 µg/ml for trans-resveratrol and gallic acid, respectively. Moreover, the samples were analyzed in different times for estimation of stability of these compounds. [ABSTRACT FROM AUTHOR]

General sensitivity formulas for maximum loading conditions of nonlinear power systems have been proposed. The proposed formulas allow computing the sensitivities of any system variable and, in particular, of the maximum loading margin with respect to arbitrary parameters. This approach extends previous results. It has also been shown that the sensitivity formulae available in the literature for static saddle-node and limit-induced bifurcation points are particular cases of the proposed general formulae. Two benchmark systems, namely a 6-bus system and the IEEE RTS-96 24-bus tests system, are used to illustrate and test the proposed technique. [ABSTRACT FROM AUTHOR]

The authors reflect on the use of umbilical cord blood as a viable alternative stem cell source for patients with hematologic diseases requiring a hematopoietic stem cell transplantation. They cite several studies that support the claims on fetal maternal immunity and antileukemia activity in cord blood transplantation (CBT). The authors think that CBT has an immunological potential for patients with hematological malignancies.

This letter presents a simple model of induction machines able to appraise the induction generator effect of the subsynchronous resonance phenomenon. The proposed model is general and can be applied to induction machines utilized in wind power applications, such as doubly-fed induction generators. A rigorous stability analysis is carried out based on the proposed model. This analysis shows that the induction generator effect leads to a Neimark–Sacker bifurcation. [ABSTRACT FROM AUTHOR]

The reconstitution of the integral membrane protein photosynthetic reaction center (RC) in polymersomes, i.e. artificial closed vesicles, was achieved by the micelle-to-vesicle transition technique, a very mild protocol based on size exclusion chromatography often used to drive the incorporation of proteins contemporarily to liposome formation. An optimized protocol was used to successfully reconstitute the protein in a fully active state in polymersomes formed by the tri-block copolymers PMOXA22–PDMS61–PMOXA22. The RC is very sensitive to its solubilizing environment and was used to probe the positioning of the protein in the vesicles. According to charge-recombination experiments and to the enzymatic activity assay, the RC is found to accommodate in the PMOXA22 region of the polymersome, facing the water bulk solution, rather than in the PDMS61 transmembrane-like region. Furthermore, polymersomes were found to preserve protein integrity efficiently as the biomimetic lipid bilayers but show a much longer temporal stability than lipid based vesicles. [ABSTRACT FROM AUTHOR]

Objectives. The Candida related denture stomatitis is a condition characterized by inflammation of the mucosa covered by the denture. The aim of the study is to evaluate the occurrence of Candida colonization and the eventual denture stomatitis, in totally edentulous patients after six and twelve months since the replacement of their dental prosthesis. Methods. Oral swabs were collected at time 0, time 1 and time 2 from palatal mucosa and tested for Candida species. Results. Out of 138 oral swabs at time 0 C. albicans were isolated in 80,70%, C. glabrata 8,77 %, and co-colonisation C. albicans/C. glabrata 7,01%. At time 1, oral swabs resulted positive were 27,53% : C. albicans were isolated in 50%, C. glabrata 23,68% and co-colonization C. albicans/C. glabrata in 26,31%. Among patients with positive oral swabs, we found denture-stomatitis in 25 patients. At time 2, oral swabs resulted positive were 68,11%: C. albicans 52,12%, C. glabrata 26,59% and co-colonization of C. albicans/C. glabrata 21,27% . Mucosal clinical examination showed signs related to denture stomatitis in 83 patients with oral swabs positive for Candida spp. Conclusion. C. albicans remains the main etiological agent accounting up to 80%, however C. glabrata has emerged as a pathogenic agent of the oral mucosa, either co-infecting with C. albicans. Our data highlight an association between Candida spp colonization and clinical features of DRS: patients who develop a C. albicans DRS tend to have a more severe compared to patients with C. glabrata DRS. The presence of a co-colonization with C. albicans and C. glabrata infection is associated with a more severe clinical form of DRS. The time factor also plays a role in respect of the mechanicalaction carried out by the same prosthesis pressure towards the oral epithelium and the possible role of this factor in altering the local immune balance. [ABSTRACT FROM AUTHOR]

An Optimal Power Flow (OPF)-based security-driven redispatching procedure to archive an appropriate security level is provided. The proposed procedure is particularly suited for security redispatching by an independent system operator. This procedure uses full ac equations and explicitly considers security limits through a stressed loading condition. Furthermore, a variety of FACTS devices can be incorporated in the redispatching problem to enhance system security. Several case studies based on the IEEE 24-bus system and on a real size model of the Italian system are analysed and discussed. [ABSTRACT FROM AUTHOR]

Barrett's esophagus (BE) is a metaplastic process in which the normal squamous epithelium of the distal esophagus is replaced by columnar lined epithelium. The aim was to gain more insight in the process of metaplasia and to identify which genes are specifically expressed by the epithelial cells and the surrounding tissues in BE. Hereto, the gene expression profile of a BE epithelial primary cell culture was compared to that of a BE biopsy. To specifically obtain the epithelial cell layer, epithelial cells from biopsies of BE were cultured using a Barrett specific culturing medium. Serial analysis of gene expression was applied to obtain a transcription library of the primary epithelial cell culture. The transcriptome was analyzed and compared to a previously described transcriptome of a BE biopsy. Validation of results by reverse transcriptase-polymerase chain reaction was performed using tissues of 16 BE patients and 16 primary cell cultures. Over 43 000 tags were sequenced. Genes specifically expressed by the Barrett epithelial cells were for instance Lipocalin 2 and Cyclin D1, whereas annexin A10, trefoil factor (TFF)1 and TFF2 were specifically expressed in the BE biopsies. The comparison of the gene expression profiles of BE primary cultured epithelial cells with BE biopsy defines a subset of genes that are specifically expressed by the epithelial cells and another subset that most likely is expressed by the underlying stromal tissues in the BE biopsy specimens. [ABSTRACT FROM AUTHOR]

We describe our experience of designing and building an electrical machine laboratory and using it for undergraduate teaching. Using small, well-balanced machines, we pursue a design that allows the closest possible man-machine contact, so that students develop a direct understanding of the machine. We summarise our practical teaching experience and lessons learned. [ABSTRACT FROM AUTHOR]

Isolated and purified reaction centers (RC) from Rhodobacter sphaeroides R-26.1 were solubilised in detergent with excess quinone and external electron donors and illuminated in the presence of pyranine. The pH change accompanying the reaction center photocycle was monitored by recording the variation of the pyranine fluorescence intensity. Using QB-depleted reaction centers or blocking the photocycle with terbutryne strongly reduced the pH change. The usefulness and limits of this technique in monitoring the pH changes during the RC photocycle are also discussed. [Copyright &y& Elsevier]

• Co-simulation platform to study the impact of stochastic UC on power system dynamics. • Monte Carlo time domain simulations of stochastic differential-algebraic equations. • Study of the impact of different levels of wind power uncertainty and volatility. • Comparison of the impact of sub-hourly stochastic and deterministic UC models. This paper discusses the impact of the sub-hourly unit commitment problem on power system dynamics. Such an impact is evaluated by means of a co-simulation platform that embeds a sub-hourly stochastic mixed-integer linear programming security constrained unit commitment (sSCUC) into a time domain simulator, as well as includes a rolling planning horizon that accounts for forecast updates. The paper considers different sub-hourly sSCUC resolutions (i.e., 5 and 15 min) and different wind penetration levels (i.e., 25 and 50%). The focus is on the transient response of the system and on frequency variations following different sSCUC strategies, and different sSCUC wind power uncertainty and volatility. The case study consists of a comprehensive set of Monte Carlo simulations based on the 39-bus system. [ABSTRACT FROM AUTHOR]

Highlights • Magnetic measurement system able to estimate the position of an ECT probe. • Performance analysis of the proposed localization system. • Mutual influence of ECT and Localization systems. Abstract Localization of eddy current probes in Nondestructive Testing allows merging the defect detection with the information about defect positions. Typically, this task requires the usage of additional and costly position measurement systems or software assisted handlers in controlled laboratory conditions. However, many of these tests require free hand movements of the eddy current probes. In addition, in many industrial applications low cost is a stringent requirement. This paper proposes a novel solution to address the considered issues. In particular, the paper describes the usage of a magnetic 2D wireless localization method, able to track the probe position during the execution of Nondestructive Tests. To the best of our knowledge, such approach is novel and promises to provide localization information in Nondestructive Testing by means of low-cost hardware. Moreover, it is characterized by a light computational burden, since it reuses most of the equipment already needed for the test itself. Preliminary results, proving the suitability of a real time simultaneous testing and localization system, are reported in this paper. [ABSTRACT FROM AUTHOR]

Recent years have seen increased interest in skeletal populations from the Imperial Roman Age in Italy, but much less is known about diet and standards of living in the subsequent medieval period. To fill this gap, we conducted a morphological analysis of human remains from Albano, an Italian town near Rome, as well as a stable isotope analysis of bone collagen to reconstruct diet. The sample was recovered from a Medieval cemetery (1040-1220 cal. yr. BP) located in the gardens of the historical Palazzo Doria Pamphili in Albano. A minimum number of 40 individuals (31 adults and 9 sub-adults) were examined using standard methods. Though the general health status of the population was good, signs of cribra orbitalia and diffuse enthesopathies were noted during the morphological examination. Stable carbon and nitrogen isotope analyses of the bone collagen from 24 adult humans and three faunal bones indicate that the diet of the population may be described as predominantly terrestrial and C3-plant based although the data for some of the individuals suggest a modest consumption of C4-(millet) based or aquatic proteins. No evidence of significant dietary differences between the sexes was found. The comparison of the isotope data from Albano with those from populations recovered in the same region is consistent with a shift from a terrestrial, possibly plant foods-dominated subsistence in the Early Middle Ages to a diet with a higher contribution from animal proteins, both terrestrial and aquatic, in the Later Middle Ages. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Most reports of chronic GVHD after cord blood transplantation (CBT) have utilized traditional diagnostic criteria. We used traditional criteria and National Institutes of Health (NIH) criteria prospectively to evaluate chronic GVHD in a cohort of 87 adult and pediatric recipients of single or double unrelated CBT for treatment of hematologic malignancies. Fifty-four patients developed traditionally defined chronic GVHD, for an estimated 2-year probability of 64%. Among 54 patients, 25 (46%) met the NIH criteria for persistent, recurrent or late acute GVHD at onset. Twenty-four (44%) had overlap chronic GVHD, including one who presented initially with late acute GVHD, and only seven (13%) had classic chronic GVHD, including one who also presented initially with late acute GVHD. Among patients who successfully discontinued all systemic immunosuppression (SI), the median time to discontinuation of corticosteroid treatment was 315 days (range 28-977), and the median time to discontinuation of all SI was 353 days (range 67-977). Chronic GVHD diagnosed by traditional criteria after CBT had a predominance of acute GVHD clinical features. [ABSTRACT FROM AUTHOR]

The life cycle of the bacterium Rhodobacter sphaeroides was investigated by isothermal microcalorimetry using two different procedures based on the use of a static ampoule and a flow cell, respectively. In the static ampoule method it is possible to follow the growth phase and also the death phase which cannot be revealed by total biomass based techniques like turbidimetry. However, different cellular metabolisms, possibly due do the oxygen limitation occurring during the bacterial life cycle, produce complex behavior in the experimental curves. In the stop-flow cell mode this limitation is overcome as the bacteria are grown outside the calorimeter under well-defined aerobic conditions and aliquots of cell suspension are transferred in the calorimeter at different time intervals. The complex behavior shown in the static ampoule mode was successfully analyzed by a population evolution model based on a Fujikawa modified logistic equation which provides a quantitative description of the process. [ABSTRACT FROM AUTHOR]

Abstract: An important issue related to power system stability is to properly damp low frequency oscillations. Traditionally, these oscillations have been damped by means of power system stabilizers. In recent years, FACTS devices equipped with a power oscillation damper have been also efficiently used for damping oscillations. This paper is a tutorial for designing such power oscillation damper. The paper presents design projects suitable for students in the power system control area at the M.Sc. and Ph.D. levels. For educational purposes, the procedure is based on Matlab and on two specific toolboxes, namely the Power System Analysis Toolbox and the Control System Toolbox. A single-machine infinite bus and a two-area test systems, with a thyristor controlled series compensator and an unified power flow controller, respectively, are used as examples for the POD design. Classroom experience has shown that the procedure helps in consolidating a better understanding of power system stability and control. [Copyright &y& Elsevier]

Abstract: Medical physics education and training requires the use of extensive imaging material and specific explanations. These requirements provide an excellent background for application of e-Learning. The EU projects Consortia EMERALD and EMIT developed five volumes of such materials, now used in 65 countries. EMERALD developed e-Learning materials in three areas of medical physics (X-ray diagnostic radiology, nuclear medicine and radiotherapy). EMIT developed e-Learning materials in two further areas: ultrasound and magnetic resonance imaging. This paper describes the development of these e-Learning materials (consisting of e-books and educational image databases). The e-books include tasks helping studying of various equipment and methods. The text of these PDF e-books is hyperlinked with respective images. The e-books are used through the readers’ own Internet browser. Each Image Database (IDB) includes a browser, which displays hundreds of images of equipment, block diagrams and graphs, image quality examples, artefacts, etc. Both the e-books and IDB are engraved on five separate CD-ROMs. Demo of these materials can be taken from www.emerald2.net. [Copyright &y& Elsevier]

• Short Range Magnetic Localization System. • Disturbance set-up following IEC/EN 61000-4-6. • Noisy Environment Localization System. • Disturbance detection and rejection method. • Magnetic measurements experimental campaign. Magnetic localization in 3D space is a challenging but promising task in those indoor applications where low costs and limited range are key requirements as in industrial and in some medical clinics' frameworks. In such cases, the localization system generally operates in disturbed environments where, in the worst case, continuous-wave disturbances could permanently affect the system performance. Therefore, the evaluation of its susceptibility to external disturbances is an issue to be assessed, before deploying the most suitable solution. Therefore, it is important to accomplish for two tasks: (i) to quantify the disturbance effect on the system performance and (ii) to propose robustness solutions to minimize the disturbance effect, thus allowing the system to behave as in regular mode. In this paper, concerning with continuous wave conducted disturbances, which act as the most impacting external disturbing sources, both the tasks are addressed by considering both analytical modeling and experimental validations. [ABSTRACT FROM AUTHOR]

• To simulate a realistic frequency signal the use of Fourier Transform is essential. • Batteries help improve effectively the electric grid frequency signal. • Their efficacy will depend on the velocity of the frequency signal itself and the velocity of intervention. • A variable Droop strategy can maintain the battery State of Charge without destabilizing the grid frequency equilibrium. This article focuses on the impact of the primary frequency control that can be provided by Battery Energy Storage Systems (BESSs) on the transient response of electric grids. A procedure based on the Fourier transform is used for synthesizing a realistic frequency signal based on the variations of load consumption and generation. The impact of BESSs is evaluated with respect to the storage capacity installed and the regulation strategy adopted and then compared with the regulation provided by conventional sources. The impact of a variable-droop strategy on the dynamic response of the grid and the BESSs State of Charges (SoCs) is also evaluated. A novel index to quantify the performance of the BESSs is proposed and discussed. The case study is based on a detailed dynamic model of the all-island Irish transmission system. [ABSTRACT FROM AUTHOR]

The article discusses the Convention on Biological Diversity's (CBD's) 2020 targets, which includes 20 SMART (specific, measurable, ambitious, realistic, time-bound) targets for 2020. According to the authors, many nations have fallen short of CBD 2010 to reduce the rate of biodiversity loss. An analysis of the CBD's SMART targets, which takes an ecosystem services approach, ways they can be strengthened, and four main things the targets are missing, including functional diversity, environmental uncertainty and target adjustments, and interaction between the targets, is presented.

A response by authors C. Perrings et al. to a letter to the editor about their article "Ecosystem Services for 2020” in the October 15, 2010 issue is presented.