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Background and purpose Multiple sclerosis-associated optic neuritis ( MSON) causes atrophy of the inner retinal layers, which can be quantified by optical coherence tomography. It has been suggested that the inter-eye percentage difference ( IEPD) of atrophy may be of diagnostic value in MSON. Methods This was a prospective, cross-sectional study in patients with multiple sclerosis and healthy controls ( HCs). Spectral-domain optical coherence tomography of both eyes was performed, followed by automated retinal layer segmentation of the peri-papillary retinal nerve fibre layer ( pRNFL) and macular ganglion cell and inner plexiform layer ( mGCIPL). Receiver operator characteristics curves were plotted and the area under the curve was calculated for group comparisons of the IEPD of the pRNFL and mGCIPL. Results There were 39 patients with bilateral MSON, 62 patients with unilateral MSON, 106 patients without MSON and 63 HCs. Diagnostic accuracy (area under the curve) of the IEPD was 0.73-0.86 for the pRNFL and 0.75-0.94 for the mGCIPL. The diagnostic sensitivity of the mGCIPL IEPD was 70% with a specificity of 97% for distinguishing unilateral MSON from HCs. For the comparison of bilateral MSON with HCs, sensitivity was 86% with a specificity of 97%. Conclusions The IEPD of the pRNFL, and more particularly the IEPD of the mGCIPL, is a useful diagnostic measure for MSON. The IEPD is a dimensionless unit and may therefore contribute to overcome device and proprietary segmentation algorithm limitations. [ABSTRACT FROM AUTHOR]

Objective: To investigate the coexistence of anterograde and retrograde trans-synaptic axonal degeneration, and to explore the relationship between selective visual pathway damage and global brain involvement in longstanding multiple sclerosis (MS). Methods: In this single-centre, cross-sectional study, patients with longstanding MS (N=222) and healthy controls (HC, N=62) were included. We analysed thickness of retinal layers (optical coherence tomography), damage within optic radiations (OR) (lesion volume and fractional anisotropy and mean diffusivity by diffusion tensor imaging) and atrophy of the visual cortex and that of grey and white matter of the whole-brain (structural MRI). Linear regression analyses were used to assess associations between the different components and for comparing patients with and without optic neuritis and HC. Results: In patients with MS, an episode of optic neuritis (MSON) was significantly associated with decreased integrity of the ORs and thinning of the peripapillary retinal nerve fibre layer (pRNFL) and macular ganglion cell complex (GCC). Lesion volume in the OR was negatively associated with pRNFL and GCC thickness in patients without optic neuritis (MSNON). The pRNFL and GCC showed associations with integrity of the OR, thickness of the primary visual cortex (only in patients with MSON), and also with global white and grey matter atrophy. In HCs, no such relationships were demonstrated. Interpretation: This study provides evidence for presence of bidirectional (both anterograde and retrograde) trans-synaptic axonal degeneration in the visual pathway of patients with MS. Additionally, thinning of the retinal pRNFL and GCC are related to global white and grey matter atrophy in addition to pathology of the visual pathway. [ABSTRACT FROM AUTHOR]

Objective Trans-synaptic axonal degeneration is a mechanism by which neurodegeneration can spread from a sick to a healthy neuron in the central nervous system. This study investigated to what extent trans-synaptic axonal degeneration takes place within the visual pathway in multiple sclerosis (MS). Methods A single-centre study, including patients with long-standing MS and healthy controls. Structural imaging of the brain (MRI) and retina (spectral-domain optical coherence tomography) were used to quantify the extent of atrophy of individual retinal layers and the primary and secondary visual cortex. Generalised estimation equations and multivariable regression analyses were used for comparisons. Results Following rigorous quality control (OSCAR-IB), data from 549 eyes of 293 subjects (230 MS, 63 healthy controls) were included. Compared with control data, there was a significant amount of atrophy of the inner retinal layers in MS following optic neuritis (ON) and also in absence of ON. For both scenarios, atrophy stopped at the level of the inner nuclear layer. In contrast, there was significant localised atrophy of the primary visual cortex and secondary visual cortex in MS following ON, but not in MS in absence of ON. Interpretation These data suggest that retrograde (trans-synaptic) axonal degeneration stops at the inner nuclear layer, a neuronal network capable of plasticity. In contrast, there seems to be no neuroplasticity of the primary visual cortex, rendering the structure vulnerable to anterograde (trans-synaptic) degeneration. [ABSTRACT FROM AUTHOR]

A frequently observed local measurement artifact with spectral domain OCT is caused by the void signal of the retinal vasculature. This study investigated the effect of suppression of blood vessel artifacts with and without retinal hyperaemia. Spectral domain OCT scans, centred on the optic nerve head, were performed in 46 healthy subjects (92 eyes). Baseline scans were made during rest, while for the follow-up scan, 23 subjects (50 %) performed strenuous physical exercise. Systemic and retinal hyperaemia were quantified. Quantification of retinal nerve fibre layer (RNFL) thickness was performed with and without suppression of retinal blood vessel artifacts. The potential systematic effect on RNFL thickness measurements was analysed using Bland-Altman plots. At baseline (no retinal hyperaemia), there was a systematic difference in RNFL thickness (3.4 μm, limits of agreement −0.9 to 7.7) with higher values if blood vessel artifacts were not suppressed. There was significant retinal hyperaemia in the exercise group ( p < 0.0001). Baseline thickness increased from 93.18 to 93.83 μm ( p < 0.05) in the exercise group using the algorithm with blood vessel artifact suppression, but no significant changes were observed using the algorithm without blood vessel artifact suppression. Retinal hyperaemia leads to blood vessel artifacts which are relevant to the precision of OCT layer segmentation algorithms. The two algorithms investigated in this study can not be used interchangeably. The algorithm with blood vessel artifact suppression was more sensitive in detecting small changes in RNFL thickness. This may be relevant for the use of OCT in a range of neurodegenerative diseases were only a small degree of retinal layer atrophy have been found so far. [ABSTRACT FROM AUTHOR]

The article describes a case of posterior internuclear ophthalmoplegia of Lutz (pINO) in a 22-year-old woman with relapsing remitting multiple sclerosis (MS). The patient complained of difficulties focusing and brief episodes of horizontal gaze evoked diplopia. Plausible mechanisms underlying pINO include a failure to relax the medial rectus muscle due to a midbrain lesion.

Due to the reduction of structure sizes in modern electronic devices reliable characterization techniques are required in the nanometer range. Since the comparable wavelengths in investigation methods are larger, near-field techniques have to be used for nano-inspection allowing sub-wavelength resolution. Also many microscopy methods with static fields imply near-field approaches. Analyzing several near-field approaches for fields and waves, a general concept for near-field description will be introduced which can be applied to various near-field interaction mechanisms. Based on scanning probe microscopy, different techniques are shown to determine locally miscellaneous properties which are important for modern electronic materials and devices. [ABSTRACT FROM AUTHOR]

In this paper the possible application of ion beam induced charge (IBIC)-microscopy for the analysis of the electrical field distributions within the depletion regions of high-power devices is discussed. The application of a reverse bias voltage allows one to obtain information about the field distribution within the device under working conditions from IBIC measurements. Such data are useful in the design process of high-power devices because excessive fields within protection elements (e.g. field ring structures) can be avoided. Charge collection spectra taken under reverse voltages of more than 1 kV are discussed. The results have been compared with simulations of the IBIC-processes using the code MEDICI. [Copyright &y& Elsevier]

Objective: Quantitative saccadic testing is a non-invasive method of evaluating the neural networks involved in the control of eye movements. The aim of this study is to provide a standardized and reproducible protocol for infrared oculography measurements of eye movements and analysis, which can be applied for various diseases in a multicenter setting. Methods: Development of a protocol to Demonstrate Eye Movement Networks with Saccades (DEMoNS) using infrared oculography. Automated analysis methods were used to calculate parameters describing the characteristics of the saccadic eye movements. The two measurements of the subjects were compared with descriptive and reproducibility statistics. Results: Infrared oculography measurements of all subjects were performed using the DEMoNS protocol and various saccadic parameters were calculated automatically from 28 subjects. Saccadic parameters such as: peak velocity, latency and saccade pair ratios showed excellent reproducibility (intra-class correlation coefficients > 0.9). Parameters describing performance of more complex tasks showed moderate to good reproducibility (intra-class correlation coefficients 0.63–0.78). Conclusions: This study provides a standardized and transparent protocol for measuring and analyzing saccadic eye movements in a multicenter setting. The DEMoNS protocol details outcome measures for treatment trial which are of excellent reproducibility. The DEMoNS protocol can be applied to the study of saccadic eye movements in various neurodegenerative and motor diseases. [ABSTRACT FROM AUTHOR]

Ferredoxins (Fd) are small iron‐sulphur proteins, with sub‐types that have evolved for specific redox functions. Ferredoxin C2 (FdC2) proteins are essential Fd homologues conserved in all photosynthetic organisms and a number of different FdC2 functions have been proposed in angiosperms. Here we use RNAi silencing in Arabidopsis thaliana to generate a viable fdC2 mutant line with near‐depleted FdC2 protein levels. Mutant leaves have ~50% less chlorophyll a and b, and chloroplasts have poorly developed thylakoid membrane structure. Transcriptomics indicates upregulation of genes involved in stress responses. Although fdC2 antisense plants show increased damage at photosystem II (PSII) when exposed to high light, PSII recovers at the same rate as wild type in the dark. This contradicts literature proposing that FdC2 regulates translation of the D1 subunit of PSII, by binding to psbA transcript. Measurement of chlorophyll biosynthesis intermediates revealed a build‐up of Mg‐protoporphyrin IX, the substrate of the aerobic cyclase. We localise FdC2 to the inner chloroplast envelope and show that the FdC2 RNAi line has a disproportionately lower protein abundance of antennae proteins, which are nuclear‐encoded and must be refolded at the envelope after import. Summary statement: Ferredoxin C2 proteins are essential [2Fe‐2S] cluster proteins present in all green organisms. Here we show that they are localised to the chloroplast envelope and use RNAi in Arabidopsis thaliana to identify a critical role in assembly of chlorophyl containing antenna complexes. [ABSTRACT FROM AUTHOR]

Introduces a system which allows precise measurement of magnetic stray fields with high spatial and temporal resolution. Background on the governing principle of the system; Features of the system; Requirements for the investigation of magnetic heads by electrons.

Thin films and coatings are used for a variety of purposes and their adhesion to the underlying substrate is essential in nearly all applications. Consequently, the need for reliable techniques to quantitatively measure adhesion is paramount. As coating systems become more complex, with, for instance, multilayered and graded architectures now commonplace in MEMS devices, there is a need to improve on existing techniques in order to assess the adhesion of the coating stack to the substrate, but also the delamination of individual interfaces within a coating stack. This requires methods to cause failure, to characterise the locus and extent of any interfacial disbond, and the models necessary to extract quantitative adhesion data from these observations. Similar challenges are faced in bulk composite materials where the adhesion between matrix and reinforcement phase or the delamination behaviour of interfaces between plies will dictate the overall mechanical response of the system There has been considerable activity in devising ways to assess adhesion in the past few decades. In fact, a survey of the literature in 1995 indicated that over 350 different techniques were available ranging from the mundane to the very sophisticated. In spite of this proliferation of techniques there has often been considerable discord amongst people working in the area as to what exactly is being measured in an adhesion test and how reliable the quantification is. In reality, the reason that there are so many techniques is that no one technique is universally applicable, and the adhesion measurements obtained on the same system using different techniques are not always directly comparable. The best adhesion test method is often that which most closely matches the intended application and therefore it will depend on the conditions to which the coated material is exposed. Given the plethora of available measurement and interpretation techniques and recent developments in techniques for characterisation of interfacial failure, we felt that it was timely to assemble a cluster of papers in the area showcasing the latest research and offering some insights in the selection of an appropriate adhesion test. The papers in this issue were solicited from major researchers in the area and represent a snapshot of the current state-of-the-art–we hope they will provide an excellent introduction to the topic for a more general audience. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various articles within the issue on topics including coating systems, adhesion and delamination of interfaces.

A 'nanoinjection' technique was used to expose sea trout (Salmo trutta) eggs to a toluene extract of settling particulate matter (SPM) and fractions thereof from the urban waters of Stockholm, Sweden. Totalextract (unfractionated), fractions collected using fractionation onan open Florisil (R) column (F1-F4), high-performance liquid chromatography (HPLC) aminopropylsilica/2 (1-pyrenyl)ethyldimethylsilulated silica column (A1-A7 and A2/P1-P3), and recombined fractions of Florisil (F-Rec) and HPLC (A-Rec) were injected into fertilized sea trout eggs. Toxicity was evaluated on the basis of deformities at hatching and in larval stages and on the basis of larvae mortality. Chemical analysis, using gas chromatography-mass spectrometry, was performed onall HPLC fractions and indicated that major components of fractions A2/P1 and A3 through A7 were polycyclic aromatic hydrocarbons (PAHs) or their alkylated derivatives. Fraction A2/P2 contained non-ortho-chlorinated biphenyls, polychlorinated dibenzo p-dioxins and dibenzofurans, and some Cl-substituted PAHs. Deformities at hatching were observed mainly in the larvae exposed to fraction A-Rec, F2 showed the highest effect on larvae mortality, and both F-Rec and A-Rec showed antagonistic mechanisms. The frequency of deformities in larvae was highest in fractions A2/P2, F4, and A-Rec. Fractions A2/P1 and F1, which partly contained similar substances, showed similar effects on deformity at hatching and larvae mortality; however, F1 showed no effect on larvae abnormality compared with A2/P1. This could have been due to antagonistic mechanisms acting in F1. [ABSTRACT FROM AUTHOR]

The interest in diamond windows for the application of high power radiation technology is increasing continuously due to its outstanding thermal and opto-electronic properties. In order to analyze the surface properties of very highly polished polycrystalline diamond in the sub-micrometer down to nanometer regime, two different near-field microscopy techniques have been employed. By using a Scanning Thermal Microscope (SThM) it is possible to uncover the varying thermal conductivity of different diamond grains. Dissimilar thermal surface properties within diamond grains have been measured with a resolution in the nm regime. Beside the fact of determining a small surface thermal conductivity compared to the well known data of bulk material, the thermal conductivity of inferior and superior diamond quality is separated quantitatively. Additionally the opto-electronic properties of the polished diamond have been investigated by Scanning Near-Field Cathodoluminescence (NF-CL). This measurement technique allows the detection of the distribution of dislocations within diamond grains with a resolution of less than 100nm. The comparison of these results, obtained by SThM and NF-CL, demonstrates a fine alignment in representing crystal lattice imperfections. [ABSTRACT FROM AUTHOR]

Diamond materials have become progressively significant in the fabrication of heat sinks for power devices and lasers. To investigate the influence of polishing on CVD-Diamond, the surfaces of 〈100〉 and 〈110〉 coatings were analyzed, after a first abrasive treatment on a 30µm diamond grit by scanning thermal microscopy based on a resistive platinum-probe. This technique describes in first order approximation the heat transfer of a metal-diamond interface. Through this method it was possible to diagnose a relevant reduction in thermal conductivity by a harsh sample preparation depending on the crystal orientation. The thermal conductivity of as deposited 〈100〉 diamond was measured at 1290 W/mK and was reduced to 520 W/mK. The thermal conductivity of as deposited 〈110〉 diamond was determined at 1780 W/mK whereas the same diamond surface, but abraded, shows a thermal conductivity of just 460 W/mK. Additionally the received images which represents the thermal conductivity qualitatively bring forward micro structures like e.g. grain boundaries. [ABSTRACT FROM AUTHOR]

An optical near-field probe is proposed in which gallium is embedded into the tip of a tapered optical glass fiber to form a scattering center. Gallium is embedded by implantation during the process of probe sharpening by a raster-scanned focused ion beam. Using quasielectrostatic approximation, it is predicted that the presence of gallium should improve the scattering efficiency by an order of magnitude in comparison with a probe without gallium implantation. Imaging of a polished waveguide with different probes shows that Ga implantation can improve the efficiency by 37 times. [ABSTRACT FROM AUTHOR]

In the microscopic hybrid system, a combination of a scanning electron microscope with a scanning probe microscope, both microprobes are used for local generation and detection of acoustic waves in the near field. At the example of ferroelectric domain imaging, a sensitivity of 200 fm in the local detection of vertical surface oscillation is demonstrated whereas the spatial resolution is within several nanometers. [ABSTRACT FROM AUTHOR]

Background and purpose: To predict disability and cognition in multiple sclerosis (MS) after 6 and 12 years, using early clinical and imaging measures. Methods: A total of 115 patients with MS were selected and followed up after 2 and 6 years, with 79 patients also being followed up after 12 years. Disability was measured using the Expanded Disability Status Scale (EDSS); cognition was measured only at follow‐up using neuropsychological testing. Predictors of interest included EDSS score, baseline brain and lesion volumes and their changes over 2 years, baseline age, clinical phenotype, sex and educational level. Results: Higher 6‐year EDSS score was predicted by early EDSS score and whole‐brain volume changes and baseline diagnosis of primary progressive MS (adjusted R2 = 0.56). Predictors for 12‐year EDSS score included larger EDSS score changes and higher T1‐hypointense lesion volumes (adjusted R2 = 0.38). Year 6 cognition was predicted by primary progressive MS phenotype, lower educational level, male sex and early whole‐brain atrophy (adjusted R2 = 0.26); year 12 predictors included male sex, lower educational level and higher baseline T1‐hypointense lesion volumes (adjusted R2 = 0.14). Conclusions: Patients with early signs of neurodegeneration and a progressive disease onset were more prone to develop both disability progression and cognitive dysfunction. Male sex and lower educational level only affected cognitive dysfunction, which remains difficult to predict and probably needs more advanced imaging measures. [ABSTRACT FROM AUTHOR]

Near-field cathodoluminescence (NFCL) has been used to characterize hydride vapor phase epitaxy grown n-GaN films. This technique can obtain high resolution luminescence images and perform local measurements of the diffusion length for minority carriers in different parts of the sample. NFCL contrast observed in round growth hillocks at the sample surface, with a diameter of less than 10 µm, is compared with that observed by conventional cathodoluminescence in scanning electron microscope (CLSEM) techniques. In particular NFCL images reveal features not detected by CLSEM which is explained by the fact that under near field conditions the signal arises from a depth of only several tens of nanometers and is then directly related to the surface hillocks. Diffusion lengths of about 0.4 and 4 µm have been found for the holes in different regions of the samples at room temperature. The order of magnitude of these minority carriers diffusion lengths is in good agreement with previous measurements performed at different GaN samples with other techniques. The NFCL contrast and the differences in the measured diffusion lengths are discussed and explained by variations in local trap concentrations. [ABSTRACT FROM AUTHOR]

The article discusses a study which was aimed to investigate the relationship of spinal cord and brain atrophy, and brain lesion load, with long-term physical disability in a large group of people with multiple scelrosis (MS). The study concluded that long-term physical disability was independently linked with atrophy of the spinal cord and brain T2 lesion load, and less consistently, with brain grey matter atrophy.

Abstract: Background: The role of antimyelin antibodies as biomarker in multiple sclerosis is subject of debate. Here antimyelin antibody reactivity against native myelin is studied in CSF and serum. Objective: To compare antimyelin antibody reactivity between patients with multiple sclerosis (MS) and patients with other neurological diseases in CSF and serum. In addition, MRI measures were studied in relation to antimyelin antibody reactivity. Methods: 77 MS patients (13 primary progressive, 27 secondary progressive and 37 relapsing remitting), 26 patients with other non-inflammatory neurological diseases and 9 patients with inflammatory neurological diseases other than MS were included. A myelin flow cytometry assay was used to detect anti-myelin antibody levels which were expressed as mean fluorescence intensity (myelin-MFI). MRI outcome measures were new or persistent T2 lesions, gadolinium enhancing T1 lesions and brain atrophy which were assessed by normalized brain volumes. Results: There was no significant difference between myelin-MFI values in serum and CSF between MS patients and controls (Mann–Whitney test p=0.19 and p=0.51). Myelin-MFI values in CSF were not correlated with number of T2 lesions (Spearman r=−0.023, p=0.85), number of gadolinium enhancing T1 lesions (Spearman r=−0.066, p=0.588) or normalized brain volume (Spearman r=−0.065, p=0.594). Conclusions: These results do not confirm an association between anti-myelin antibody reactivity and the presence of MS or MRI measures of disease activity. [Copyright &y& Elsevier]

The local thermal conductivity of polycrystalline aluminum nitride (AlN) ceramics is measured and imaged by using a scanning thermal microscope (SThM) and complementary scanning electron microscope (SEM) based techniques at room temperature. The quantitative thermal conductivity for the AlN sample is gained by using a SThM with a spatial resolution of sub-micrometer scale through using the 3ω method. A thermal conductivity of 308 W/m·K within grains corresponding to that of high-purity single crystal AlN is obtained. The slight differences in thermal conduction between the adjacent grains are found to result from crystallographic misorientations, as demonstrated in the electron backscattered diffraction. A much lower thermal conductivity at the grain boundary is due to impurities and defects enriched in these sites, as indicated by energy dispersive X-ray spectroscopy [ABSTRACT FROM AUTHOR]

Background and purpose: The occurrence of intermediate uveitis, which is characterized by the presence of vitreous haze (VH), in patients with multiple sclerosis (MS) may be a sign of coexistent inflammatory central nervous system (CNS) disease activity. Using an automated algorithm to quantify VH on optical coherence tomography (OCT) scans, the aim was to investigate whether VH in MS patients is associated with signs of inflammatory CNS disease activity. Methods: Vitreous haze was quantified on OCT macular volume scans of 290 MS patients and 85 healthy controls (HCs). The relationship between VH and clinical, retinal OCT and magnetic resonance imaging parameters of inflammatory disease activity was investigated using generalized estimating equations. Results: Mean VH scores did not differ between patients and HCs (P = 0.629). Six patients (2.1%) showed values higher than the highest of the controls by HCs. VH scores did not differ between the different disease types or between eyes with and without a history of optic neuritis (P = 0.132). VH was not associated with inner nuclear layer volume on OCT (P = 0.233), cerebral T2 lesion load on magnetic resonance imaging (P = 0.416) or the development of new relapses (P = 0.205). Conclusion: In this study, OCT‐based automated VH estimation did not detect increased vitreous inflammation in MS patients compared to HCs and did not find an association with CNS inflammatory burden. [ABSTRACT FROM AUTHOR]

The article examines the synthesis and characteristics of cell-permeable and biocompatible polymeric nanoparticles for apoptosis imaging. The study shows that this polymeric nanoparticle was efficiently and specifically cleaved by both caspase-3 and caspase 7 in cell-free condition and cell culture system. The nanoparticle can be used to measure apoptosis in cell-based high-throughput screens.