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Using a fully solution‐processed cross‐linking method, we demonstrate a technique for fabricating multilayer OLEDs based on Thermally Activated Delayed Fluorescence (TADF). Our approach addresses the challenge of interfacial miscibility frequently encountered during fabrication and remains compatible with industrial printing and coating technologies. Multilayer TADF‐based OLEDs utilizing fully inkjet‐printed organic layers are successfully manufactured. The fully printed devices exhibit a maximum luminance of 2830 cd/m², a maximum current efficiency of 6.52 cd/A, and a maximum external quantum efficiency (EQE) of 1.98%.

The high percentage of energy consumption by fossil fuels in the building sector in combination with climate change across the globe increased the need to move into more sustainable building practices. Thus, the integration of sustainable strategies and active solar energy systems into the design process is becoming a tool for the reduction of the energy demand and improvement of the energy performance of existing and new buildings.

We demonstrate proof-of-concept refractive-index structures with large refractive-index-gradient profiles, using a micro-contact photothermal annealing (μCPA) process to pattern organic/inorganic hybrid materials comprising titanium oxide hydrate within a poly(vinyl alcohol) binder. A significant refractive index modulation of up to Δn +0.05 can be achieved with μCPA within less than a second of pulsed lamp exposure, which promises the potential for a high throughput fabrication process of photonic structures with a polymer-based system.

Background: Older adults living in nursing homes have an increased risk of adverse outcomes.However, the role of body composition in vital health and quality of life parameters such asfunctional capacity and cognitive function is less studied in this group of older adults compared tocommunity-dwelling counterparts. Objective: The aim of the present study was to examine the association of body composition withfunctional capacity and cognitive function in nursing home residents. Methods: Fifty-three older adults (82.8 ± 7.3 years) were enrolled in this study and they underwentbody composition evaluation, functional capacity and cognitive function measurements. Results: The results showed a high prevalence of obesity accompanied by functional capacity limitationsand cognitive impairment in older adults living in nursing homes. Partial correlations, controllingfor age, showed that body fat percentage was positively correlated with sit-to-stand-5 (r =0.310, p = 0.025) and timed-up-and-go (r = 0.331, p = 0.017), and negatively correlated with handgripstrength test results (r = -0.431, p<0.001), whereas greater lean body mass was associated withbetter sit-to-stand-5 (r = -0.410, p = 0.003), handgrip strength (r=0.624, p<0.001) and cognitivefunction performance (r = 0.302, p = 0.037). Conclusions: These important associations reinforce the need to develop effective healthy lifestyleinterventions targeting both lean mass and body fat to combat functional and cognitive decline innursing home residents.

The importance of the O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status as a predictive factor for the response to chemotherapy with temozolomide is well established. Its significance though at stratifying glioblastoma (GBM) patients in regard to their prognostic factors and the impact of surgical approach on them has not been identified.

The vivid iridescent response from particular butterflies is as an excellent example of how micro-engineered hierarchical architectures that combine physical structures and pigmentary inclusions create unique colouration. To date, however, detailed knowledge is missing to replicate such sophisticated structures in a robust, reliable manner. Here, we deliver spheres-in-grating assemblies with colouration effects as found in nature, exploiting embossed polymer gratings and self-assembled light-absorbing micro-spheres.

Introduction: There are limited data regarding cerebrospinal fluid (CSF) and plasma biomarkers among patients with Cerebral Amyloid Angiopathy (CAA). We sought to investigate the levels of four biomarkers [β-amyloids (Aβ42 and Aβ40), total tau (tau) and phosphorylated tau (p-tau)] in CAA patients compared to healthy controls (HC) and patients with Alzheimer Disease (AD).Patients and methods: A systematic review and meta-analysis of published studies, including also a 5 year single-center cohort study, with available data on CSF and plasma biomarkers in symptomatic sporadic CAA versus HC and AD was conducted. Biomarkers’ comparisons were investigated using random-effects models based on the ratio of mean (RoM) biomarker concentrations. RoM < 1 and RoM > 1 indicate lower and higher biomarker concentration in CAA compared to another population, respectively.Results: We identified nine cohorts, comprising 327 CAA patients (mean age: 71 ± 5 years; women: 45%) versus 336 HC (mean age: 65 ± 5 years; women: 45%) and 384 AD patients (mean age: 68 ± 3 years; women: 53%) with available data on CSF biomarkers. CSF Aβ42 levels [RoM: 0.47; 95% CI: 0.36–0.62; p< 0.0001], Aβ40 levels [RoM: 0.70; 95% CI: 0.63–0.79; p< 0.0001] and the ratio Aβ42/Aβ40 [RoM: 0.62; 95% CI: 0.39–0.98; p= 0.0438] differentiated CAA from HC. CSF Aβ40 levels [RoM: 0.73; 95% CI: 0.64–0.83; p= 0.0003] differentiated CAA from AD. CSF tau and p-tau levels differentiated CAA from HC [RoM: 1.71; 95% CI: 1.41–2.09; p= 0.0002 and RoM: 1.44; 95% CI: 1.20–1.73; p= 0.0014, respectively] and from AD [RoM: 0.65; 95% CI: 0.58–0.72; p< 0.0001 and RoM: 0.64; 95% CI: 0.57–0.71; p< 0.0001, respectively]. Plasma Aβ42 [RoM: 1.14; 95% CI: 0.89–1.45; p= 0.2079] and Aβ40 [RoM: 1.07; 95% CI: 0.91–1.25; p= 0.3306] levels were comparable between CAA and HC.Conclusions: CAA is characterized by a distinct CSF biomarker pattern compared to HC and AD. CSF Aβ40 levels are lower in CAA compared to HC and AD, while tau and p-tau levels are higher in CAA compared to HC, but lower in comparison to AD patients.

The optoelectronic landscape of conjugated polymers is intimately related to their molecular arrangement and packing, with minute changes in local order, such as chain conformation and torsional backbone order/disorder, frequently having a substantial effect on macroscopic properties. While many of these local features can be manipulated via chemical design, the synthesis of a series of compounds is often required to elucidate correlations between chemical structure and macromolecular ordering. Here, we show that blending semiconducting polymers with insulating commodity plastics enables controlled manipulation of the semiconductor backbone planarity. The key is to create a polarity difference between the semiconductor backbone and its side chains, while matching the polarity of the side chains and the additive. We demonstrate the applicability of this approach through judicious comparison of regioregular poly(3-hexylthiophene) (P3HT) with two of its more polar derivatives, namely the diblock copolymer poly(3-hexylthiophene)-block-poly(ethylene oxide) (P3HT-b-PEO) and the graft polymer poly[3-but(ethylene oxide)thiophene] (P3BEOT), as well as their blends with poly(ethylene oxide) (PEO). Proximity between polar side chains and a similarly polar additive reduces steric hindrance between individual chain segments by essentially “expelling” the side chains away from the semiconducting backbones. This process, shown to be facilitated via exposure to polar environments such as humid air/water vapor, facilitates backbone realignment toward specific chain arrangements and, in particular, planar backbone configurations.

Understanding the structure–property relationships that govern exciton dissociation into polarons in conjugated polymers is key in developing materials for optoelectronic applications such as light-emitting diodes and solar cells. Here, the polymer poly(9,9-dioctylfluorene) (PFO), which can form a minority population of chain segments in a distinct, lower-energy “β-phase” conformation, is studied to examine the influence of conformation and microstructure on polaron generation in neat thin films. Through use of ultrafast transient absorption spectroscopy to probe PFO thin films with glassy-phase and β-phase microstructures and selectively exciting each phase independently, the dynamics of exciton dissociation are resolved. Ultrafast polaron generation is consistently found to be significantly higher and long-lived in thin films containing β-phase chain segments, with an average polaron yield that increases by over a factor of three to 4.9% vs 1.4% in glassy-phase films. The higher polaron yield, attributed to an increased exciton dissociation yield at the interface between conformational phases, is most likely due to a combination of the significant energetic differences between glassy-phase and β-phase segments and disparities in electronic delocalization and charge carrier mobilities between phases.

Fahr disease, also known as familial idiopathic basal ganglia calcification, is a rare neurodegenerative disorder, the etiology of which remains unknown. Given its various presentations, Fahr disease is presumed to be underdiagnosed and its prevalence underestimated. We present a case of Fahr disease that presented mainly with pure psychiatric symptoms. Isolated psychiatric symptoms without neurological manifestations are rarely seen in patients diagnosed with Fahr disease. Psychiatrists should consider Fahr disease as a differential diagnosis in the evaluation of psychiatric illness.

BackgroundIntrasaccular flow disruption represents a new paradigm in endovascular treatment of wide-necked bifurcation aneurysms.ObjectiveTo perform a matched case–control study comparing complications and angiographic outcome using the Woven Endobridge (WEB) device and stent-assisted coiling (SAC).MethodsSixty-six patients treated with the WEB at three German tertiary care centers were included and matched with 66 patients treated with SAC based on aneurysm location and unruptured/ruptured aneurysm status. Parameters were retrospectively analysed and compared between the treatment groups using inverse probability of treatment weighting (IPTW) with propensity scores.ResultsProcedural complication rates were 12.1% in the WEB group and 21.2% in the SAC group, which was statistically significant after IPTW adjustment (OR=2.2, 95% CI 1.08 to 4.4, p=0.03). Favourable outcome (modified Rankin scale score ≤2) was achieved by 57/66 (86.4%) in the WEB group and 57/66 (86.4%) in the SAC group (p=1.0). At mid-term follow-up, a similar number of aneurysms achieved adequate occlusion (complete occlusion or neck remnant) in the WEB group (93.9%) and in the SAC group (93.9%, p=1.0). Re-treatment was performed in 10.6% after WEB embolization and 12.1% after SAC (p=1.0).ConclusionsThe WEB provides similar mid-term aneurysm occlusion rates to those of SAC, with no additional morbidity and potentially lower complication rates. Long-term outcome analysis will provide a definite conclusion on the use of WEB for intracranial aneurysms.

Objective To evaluate the effectiveness of early (<3 months) cranioplasty (CP) and late CP (>3 months) on post-operative complications in patients receiving decompressive craniotomy (DC) for traumatic brain injury (TBI).Methods The Cochrane Library, PubMed and EMBASE databases were systematically searched for studies published prior to May 21, 2017. A meta-analysis examined post-operative overall complication rates, infection rates, subdural fluid collection and operating times according to early and late CP.Results Of the initial 1675 references, five studies, all cohort, involving a total of 413 patients, were selected for the review. There was no difference between early and late CP in post-operative overall complication rate (RR=0.68, 95%CI [0.36, 1.29]) and the post-operative infection rate (RR=0.50, 95%CI [0.20, 1.24]) in patients receiving DC for TBI. However, there was a significant difference in post-operative subdural effusion (RR=0.24, 95%CI [0.07, 0.78]) and mean operative time (mean difference = −33.02 min, 95%CI [−48.19, −17.84]) both in favour of early CP.Conclusions No differences were found between early and late CP in post-operative overall complications and procedural related infections in patients receiving DC for TBI, but early CP reduced the complication of subdural effusion and the mean operating time. These findings need to be confirmed by large, randomised controlled trials.

We report a novel approach to achieve deep-blue, high-efficiency, and long-lived solution-processed polymer light-emitting diodes (PLEDs) via a simple molecular level conformation change of an emissive conjugated polymer. We introduce rigid β-phase segments into a 95% fluorene—5% arylamine copolymer emissive layer. The arylamine moieties at low density act as efficient exciton formation sites in PLEDs, whereas the conformational change alters the nature of the dominant luminescence from a broad, charge transfer like emission to a significantly blue-shifted and highly vibronically structured excitonic emission. As a consequence, we observe a significant improvement in the Commission International de L’Eclairage (x, y) coordinates from (0.149, 0.175) to (0.145, 0.123) while maintaining high efficiency and improved stability. We achieve a peak luminous efficiency, η = 3.60 cd/A, and a luminous power efficiency, ηw= 2.44 lm/W, values that represent state-of-the-art performance for single copolymer deep-blue PLEDs. These values are 5-fold better than for otherwise-equivalent, β-phase poly(9,9-dioctylfluorene) PLEDs (0.70 cd/A and 0.38 lm/W). This report represents the first demonstration of the use of molecular conformation as a simple but effective method to control the optoelectronic properties of a fluorene copolymer; previous examples have been confined to homopolymers.

This study examined the effects of a simulated judo competition among cadet judo athletes in physiological and metabolic responses. Nine cadet judo athletes participated in the study. The simulated competition consisted of four 4-minute judo matches, separated by fifteen minutes of recovery. During each match, the athletes’ attacks were recorded, and during the recovery time, concentrations of lactate (La), triglycerides (TG), and glucose (GLU) were measured. The heart rate (HR) and the rating of perceived exertion (RPE) were also obtained. The results of this study indicate the high impact multiple judo matches have in cardiovascular stress and perceived exertion and highlight the main metabolic involvement of anaerobic pathway. We conclude that the increase in blood lactate concentration is not a limiting factor in judo performance in multiple one-day judo matches. In addition, in the cadets’ category, the 14-minutes interval between the matches is long enough to positively influence blood lactate clearance.

Radiotherapy of central nervous system (CNS) is treatment against many paediatric cancers, even if it is a well-recognized risk factor for meningioma formation. An increased risk of developing secondary brain tumors like radiation-induced meningiomas (RIM) is related to irradiated patients.

This work uses simulations to predict the performance of InAlAsSb solar cells for use as the top cell of triple junction cells lattice matched to InP. The InP-based material system has the potential to achieve extremely high efficiencies due the availability of lattice matched materials close to the ideal bandgaps for solar energy conversion. The band-parameters, optical properties and minority carrier transport properties are modeled based on literature data for the InAlAsSb quaternary, and an analytical drift-diffusion model is used to realistically predict the solar cell performance.

The use of plasmonic nanostructures for the removal of unwanted long-lived states is investigated. We show that the total decay rate of such a state can be increased by up to 4 orders of magnitude, as compared to its intrinsic radiative decay rate, while leaving other neighboring optical transitions unaffected. For the specific case of molecular triplet excited states, we show that the use of a “plasmonic sink” has the potential to reduce photobleaching and ground-state depletion by at least 2 orders of magnitude. We consider, in addition, the impact of such structures on the performance of organic semiconductor lasers and show that, under realistic device conditions, plasmonic sinks have the capacity to increase the achievable laser repetition rate by a factor equal to the triplet decay rate enhancement. We conclude by studying the effect of exciton diffusion on the triplet density in the presence of metallic nanoparticles.

Atherosclerotic renal artery stenosis (ARAS) is a progressive disease and it is usually associated with hypertension as well as with chronic kidney and cardiovascular disease. Although the anatomical lesions are relatively easy to depict, there is need to identify diagnostic methods to establish the functional significance of the stenosis and predict the response to revascularization. Over the last years, renal revascularization appears to be increasingly performed in patients with ARAS. However, controversy abounds as so far prospective, randomised trials did not document any benefit of revascularization with or without stenting plus optimal medical treatment over optimal medical treatment alone. In this review, we discuss the current data in the field of diagnosis and management of patients with ARAS

The modeling of high efficiency, multijunction (MJ) solar cells away from the radiative limit is presented. In the model, we quantify the effect of non-radiative recombination by using radiative efficiency as a figure of merit to extract realistic values of performance under different spectral conditions. This approach represents a deviation from the traditional detailed balance approximation, where losses in the device are assumed to occur purely through radiative recombination. For lattice matched multijunction solar cells, the model predicts efficiency values of 37.1% for AM0 conditions and 52.8% under AM1.5D at 1 sun and 500X, respectively. In addition to the theoretical study, we present an experimental approach to achieving these high efficiencies by implementing a lattice matched triple junction (TJ) solar cell grown on InP substrates. The projected efficiencies of this approach are compared to results for the state of the art inverted-metamorphic (IMM) technology. We account for the effect of metamorphic junctions, essential in IMM technology, by employing reduced radiative efficiencies as derived from recent data. We show that high efficiencies, comparable to current GaAs-based MJ technology, can be accomplished without any relaxed layers for growth on InP, and derive the optimum energy gaps, material alloys, and quantum-well structures necessary to realize them.

Materials in which sub‐wavelength physical structures, rather than variations in chemical composition, are used to modify the nature of their interaction with electromagnetic radiation form the promising new class of metamaterials. For molecular materials one has an intriguing alternative, namely structuring the conformation or physical geometry of the molecule. In order for this to be an effective methodology one needs the change in conformation i) to engender a significant change in electromagnetic properties and ii) to be spatially controllable to allow patterning of practical structures. In this paper the potential of such an approach is demonstrated through spatial patterning, via masked solvent vapor exposure, of the β‐phase conformation in poly(9,9‐dioctylfluorene) (PFO). Significantly the conformation change approach preserves a planar film format and is found not to negatively impact on optical gain properties, both very attractive features for optoelectronic and photonic lightwave circuit applications. As a specific demonstration the ability to spatially control the lasing wavelength for samples in which a β‐phase conformation is selectively patterned in a glassy PFO film spin coated atop a one‐dimensional distributed‐feedback grating etched into a spectrosil substrate is shown.

The majority of hemorrhagic arachnoid cysts are correlated with trauma or aneurysmal rupture. We report on a 35-year-old woman with acute headache and an intracranial mass lesion that was hyperdense in CT and hyperintense in conventional MRI images. The history and imaging were negative for trauma or vascular anomaly. Diffusion-weighted imaging (DWI) clearly demonstrated a large right anterior and middle cranial fossa arachnoid cyst with associated subacute intracystic hemorrhage without subdural hematoma. DWI offers invaluable information for the differential diagnosis of hemorrhagic arachnoid cysts from other extra-axial space-occupying lesions.

To investigate the mechanisms via which lung volume related caudal tracheal traction decreases upper airway collapsibility.

We report the use of light-emitting conjugated polymer materials to wavelength-convert the emission from a two-dimensional array of micropixellated InGaN light-emitting diodes (LEDs). We demonstrate hybrid organic/inorganic light-emitting devices that can operate across the entire visible spectrum, and we also fabricate white-emitting versions of these devices by employing single layers of carefully adjusted polymer blends in which cascade non-radiative energy transfer occurs between the constituent materials. Additional colours may be easily obtained by tuning the composition of the polymer blends. Our work demonstrates that the combination of conjugated polymers and UV micro-LED arrays provides an attractive approach to developing microscale wavelength-tunable light sources and may provide a route to low-cost full-colour microdisplays and other instrumentation devices.

The obstructive sleep apnea hypopnea syndrome (OSAHS) is a disorder characterized by repetitive closure and reopening of the upper airway during sleep. Upper airway luminal patency is influenced by the surface tension (gamma) acting within the liquid layer lining the upper airway. The aim of the present study was to examine the gamma of upper airway mucosal lining liquid (UAL) in both healthy subjects and patients with OSAHS before and after sleep.

AlAs and GaAs dispersion properties in the mid-IR (λ ~ 2–6 m) spectral region have been measured for the first time by modelling reflectivity spectra from a GaAs/AlAs &lquot;distributed Bragg reflector&rquot; in the near- (1–1.7 m) and mid- (2–6 m) IR spectral ranges. The near-IR spectra are first modelled, using existing dispersion data, for layer thickness calibrations. Modelling the mid-IR reflectivity then allows the mid-IR dispersion properties to be extracted. The resulting mid-IR dispersion curves can be accurately parameterized with a &lquot;single effective oscillator&rquot; model and represent significant improvement over previous theoretical estimates.

This paper reviews the research effort to date into optical wireless communication systems, both in academic and industrial contexts. The idea of using the optical medium for wireless communications is not new, having been proposed as a means for indoor communications almost two decades ago. However, the last few years have seen an explosive interest in the potential for free space optical systems to provide portable data communications. One of the prime motivators for reconsidering the use of an optical carrier in the wireless context is the demand for greater transmission bandwidths. The radio frequency spectrum is already exceedingly congested and frequency allocations of sufficient bandwidths are extremely hard to obtain. Further, for the high bandwidth services envisaged, the use of microwave or mm-wave systems will be required, where device technology is currently either expensive or immature. Proponents of optical wireless systems argue that the optical medium is the only cost-effective way to provide high bit-rate mobile services to volume markets. This paper identifies the technical obstacles and limitations of indoor optical wireless delivery in addition to techniques for mitigating these effects and shows that infrared is a viable alternative to radio for certain applications.

A series of strained InxGa1-xAs/AlAs multiple quantum well p–i–n diodes with x varyingfrom 0·06 to 0·15 has been investigated. High resolution X-ray diffractometry was used to determine the In concentration, the well width, and the degree of strain relaxation for the higher In samples. Simulations enabled information concerning the thickness uniformity and interfacial abruptness to be obtained. Reciprocal space mapping permitted direct measurement of residual strain and tilt in the layers. Photocurrent spectroscopy for both pseudomorphic and partially relaxed samples showed strong room temperature excitonic features and a strong quantum confined Stark effect under an applied electric field, attributed to the confining potential of the AlAs barriers. The excitonic spectral positions were in good agreement with band structure calculations made using the structural parameters determined using X-ray diffractometry.MST/3248

Patients with neurofibromatosis 2 (NF2) are predisposed to a variety of neoplastic and dysplastic lesions, including schwannomas, neurofibromas, meningiomas, astrocytomas, and ependymomas, as well as entities such as meningioangiomatosis, schwannosis, and hamartomas. This study reports a unique intracerebral frontotemporal tumor in a 6-year-old boy with presumed NF2, on the basis of bilateral cerebellopontine tumors consistent with acoustic neuromas. The intracerebral tumor revealed a variety of histological patterns, including foci of primitive neuroectodermal tumor (PNET), low-grade astrocytoma and ependymoma, as well as neuroepithelial rests with immature ganglion cells and hamartomatous areas. The MIB-1 labeling index ranged from 63% in the foci of PNET to 4-7% in other foci. The PNET component revealed immunopositivity for synaptophysin and neurofilament and showed cells with delicate intercellular junctions, profiles of rough endoplasmic reticulum, mitochondria, and dense core granules, and cell processes with microtubules and neurofilaments. The glial and ependymal components showed bundles of glial filaments and prominent cell junctions, cilia, and microvilli. The hamartomatous component also included aggregates of cells with hyaline eosinophilic cytoplasm. By EM these cells contained abundant amorphous flocculent material. This constellation of pathologic findings, especially the finding of PNET, is unique and not previously reported in the setting of NF2.

The authors report the electroabsorption response of strained multiquantum well In0.2Ga0.8As/GaAs structures as a function of increasing barrier thickness. We find that a tradeoff exists between improved structural quality and reduced performance due to the increase in nonabsorbing material. However changing the barrier from 100 to 200 Å causes a 25% increase in the maximum absorption change and a significant lowering of the insertion loss.

To date, diagnosis of IDH1 mutation is based on DNA sequencing and immunohistochemistry, methods limited in terms of sensitivity and ease of use. Recently, the diagnosis of IDH1 mutation by real-time polymerase chain reaction was introduced as an alternative method. In this study, real-time polymerase chain reaction was validated as a tool for detection of IDH1 mutation, and expression levels were analyzed for correlation with course of the disease. A total of 113 tumor samples were obtained intraoperatively from 84 patients with glioma having a diagnosis of diffuse glioma (World Health Organization II), anaplastic glioma (World Health Organization III), secondary glioblastoma ± chemotherapy, primary glioblastoma ± chemotherapy (World Health Organization IV). Tumor samples were snap frozen and processed for sectioning and RNA and protein isolation. Presence of IDH1 mutation was determined by DNA sequencing. Hereafter, quantitative expression of IDH1 messenger RNA was assessed using real-time polymerase chain reaction with specific primers for IDH1 mutation and –wt; protein expression was verified by Western Blot analysis and immunohistochemistry. Additionally, 19 samples of low-grade glioma and their consecutive high-grade glioma were analyzed at different time points of the disease. IDH1 mutation was identified in 63% of samples by DNA sequencing. In correlation with the real-time polymerase chain reaction results, a cutoff value was determined. Above this threshold, sensitivity and specificity of real-time polymerase chain reaction in detecting IDH1 mutation were 98% and 94%, respectively. Quantitative analysis revealed that IDH1 mutation expression is upregulated in secondary glioblastoma (mean ± standard error of mean: 3.52 ± 0.55) compared to lower grade glioma (II = 1.54 ± 0.22; III = 1.67 ± 0.23). In contrast, IDH1 wt expression is upregulated in all glioma grades (concentration >0.1) compared to control brain tissue (0.007 ± 0.0016). Western Blot analysis showed a high concordance to both sequencing and real-time polymerase chain reaction results in qualitative analysis of IDH1 mutation status (specificity 100% and sensitivity 100%). Moreover, semiquantitative protein expression analysis also showed higher expression levels of mutated IDH1 in secondary glioblastoma. In our study, real-time polymerase chain reaction and Western Blot analysis were found to be highly efficient methods in detecting IDH1 mutation in glioma samples. As cost-effective and time-saving methods, real-time polymerase chain reaction and Western Blot analysis may therefore play an important role in IDH1 mutation analysis in the future. IDH1 mutation expression level was found to correlate with the course of disease to a certain extent. Yet, clinical factors as recurrent disease or prior radiochemotherapy did not alter IDH1 mutation expression level.

Background: Quantitative real-time reverse-transcription polymerase chain reaction is frequently used as research tool in experimental oncology. There are some studies of valid endogenous control genes in the field of human glioma research, which, however, only focus on the comparison between normal brain with tumor tissue and malignant transformation toward secondary glioblastomas. Aim of this study was to validate a more general reference gene also suitable for pre- and posttreatment analysis and other evaluations (eg, primary vs secondary glioblastoma).Methods: This quantitative polymerase chain reaction analysis was performed to test a panel of the 6 most suitable reference genes from other studies representing different physiological pathways (ACTB, GAPDH, POLR2A, RPL13A, SDHA, and TBP) in all common glioma groups, namely: diffuse astrocytoma World Health Organization II, anaplastic astrocytoma World Health Organization III, secondary glioblastoma World Health Organization IV with and without chemotherapy, primary glioblastoma, recurrent glioblastoma, and gliomas before and after radiation. Expression stability was tested during the longitudinal course of the disease in 8 single patients.Results: Evaluation of the expression levels of the 6 target genes showed that ACTB, GAPDH, and RPL13A show higher expression compared to SDHA, POLR2A, and TBP. ACTB, GAPDH, and RPL13A showed different expression levels between astrozytoma grade II and primary glioblastoma. Except for this difference, the candidate genes were not differentially expressed between primary and secondary glioblastomas and between the World Health Organization tumor grades. Furthermore, they remained stable before and after radiotherapy and/or chemotherapy. Therefore, they are adequate references for glioblastoma gene expression studies. The comparison of all tested genes resulted in SDHA and ACTB as most stable reference genes determined by the NormFinder software. Our data revealed lowest intragroup variation in the SDHA, highest in the RPL13A gene.Conclusions: All tested genes may be recommended as universal reference genes for data normalization in gene expression studies under different treatment regimens both in primary glioblastomas and astrocytomas of different grades (World Health Organization grades II-IV), respectively. In summary, ACTB and SDHA exhibited the best stability values and showed the lowest intergroup expression variability.

The first observation of electro-absorption in a InGaAsN-GaAs single quantum well pin-diode structure is reported. Clear excitonic resonances were observed at room temperature at 1150 4;nm and a strong Stark shift is obtained for applied fields of up to 2.6×107 4;V/m. The field induced changes in refractive index were calculated at 1300 and 1550 4;nm and it is concluded that low voltage phase modulators could be fabricated using this material.

High efficiencies and low voltages for resonant-cavity light-emitting diodes operating close to 650 nm are reported. Peak external quantum efficiencies of 6% are obtained for a low current injection of ~1 mA, giving an optical power output of 0.1 mW. For higher current injection at 13 mA, 1 mW of power is produced with a slightly lower, but modest, efficiency of 4%. These record high efficiencies mean that high power performance previously achieved in RCLEDs at the inherently more efficient wavelength of 660 nm can now be replicated in 650 nm devices. Forward biased operating voltages are between 1.7 and 1.9 V for a current range of 0 – 60 mA.