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In the present study, a dispersive solid-phase extraction based on colloidal gel is presented for rapid/efficient determination of ethalfluralin with high precision and accuracy. The synthesis of colloidal gel was accomplished by combining manganese dioxide (MnO2) nanoparticles with the deep eutectic solvent (DES) as the preferred ionic fluid. Using a one-factor-at-a-time approach, variables affecting the extraction efficiency of the developed method were optimized to achieve the highest extraction efficiency and stability for the determination of the target analyte. In line with data obtained, the limit of detection value for the target analyte was determined to be 10.2 µg/kg. In order to demonstrate the accuracy/applicability of the developed method in complex matrices, different soy flour samples were utilized, and extraction procedures were conducted under pre-determined optimal method conditions. Matrix matching calibration strategy was applied to spiked samples, followed by the determination of percent recovery results ranging between 92.1 and 114.2%.

Human society is dependent on nature1,2, but whether our ecological foundations are at risk remains unknown in the absence of systematic monitoring of species’ populations3. Knowledge of species fluctuations is particularly inadequate in the marine realm4. Here we assess the population trends of 1,057 common shallow reef species from multiple phyla at 1,636 sites around Australia over the past decade. Most populations decreased over this period, including many tropical fishes, temperate invertebrates (particularly echinoderms) and southwestern Australian macroalgae, whereas coral populations remained relatively stable. Population declines typically followed heatwave years, when local water temperatures were more than 0.5 °C above temperatures in 2008. Following heatwaves5,6, species abundances generally tended to decline near warm range edges, and increase near cool range edges. More than 30% of shallow invertebrate species in cool latitudes exhibited high extinction risk, with rapidly declining populations trapped by deep ocean barriers, preventing poleward retreat as temperatures rise. Greater conservation effort is needed to safeguard temperate marine ecosystems, which are disproportionately threatened and include species with deep evolutionary roots. Fundamental among such efforts, and broader societal needs to efficiently adapt to interacting anthropogenic and natural pressures, is greatly expanded monitoring of species’ population trends7,8.

Encapsulation of nanoparticles (NP) by a shell material provides characteristics and properties not achievable by the individual materials of the core and the shell. Therefore, the characterization of morphology parameters of core–shell nanoparticles (CSNP) is critical to determine their performance. In this work, an analysis to determine the shell thickness of CSNP has been conducted using a simple and noniterative procedure known as Shard’s methodology, where the conversion of XPS peak intensities into shell thickness can be performed. Implementing the Simulation of Electron Spectra for Surface Analysis (SESSA), we acquired an insight into the morphology and composition of the CSNP by simulating the spectra from XPS to extract the parameters (Shard’s methodology) and confirm the core–shell ratio with experimental spectra to quantify the shell thickness. The CSNPs were synthesized with reverse micelle templating using diblock copolymer micellar templates, using various ratios of tin and gold precursors to form SnO2@Au core–shell nanoparticles. Considering elastic-scattering effects, a good agreement was found in the quantification of the shell thicknesses with a variation inside the ±10% regime of the effective attenuation length (EAL). This work demonstrates the use of simulation software as a complementary tool to a multitechnique analysis for a detailed understanding of CSNP.

A sesquiterpenoid with an unprecedented 5/5/4 tricyclic skeleton (1), a nor-sesquiterpenoid with a rare 6/7 bicyclic skeleton (2), 10 new sesquiterpenoids (3–12), and six known analogues (13–18) were isolated from the whole plants of Seriphidium transiliense. The structures of compounds 1–12were elucidated by spectroscopic data analysis. Compound 7showed melanogenic promotion activity in murine melanoma (B16) cells more potent than the positive control used, 8-methoxypsoralen (8-MOP). Further mechanistic studies indicated that compound 7promotes melanogenesis through activating the transcription of microphthalmia-associated transcription factor (MITF) and tyrosinase family genes in B16 cells. Moreover, compound 7also inhibited the expression of IFN-γ-chemokine through the JAK/STAT signaling pathway in immortalized human keratinocyte (HaCaT) cells. These results suggest that the sesquiterpenoid 7shows potential activity for treating vitiligo.

Governments are negotiating actions intended to halt biodiversity loss and put it on a path to recovery by 2050. Here, we show that bending the curve for biodiversity is possible, but only if actions are implemented urgently and in an integrated manner. Connecting these actions to biodiversity outcomes and tracking progress remain a challenge.

In this study, an analytical strategy was proposed for the determination of cobalt at trace levels by using a flame atomic absorption spectrophotometry (FAAS) system after magnetic hydrogel based dispersive solid phase extraction (MH-DSPE). Poly(vinyl alcohol) based magnetic hydrogels (PVA-MH) were synthesized easily, quickly, and cost effectively in the laboratory and used as an adsorbent material in the microextraction process. Under the optimum experimental conditions, the limit of detection (LOD) and limit of quantitation (LOQ) values were recorded as 4.2 and 14.1 μg L−1, respectively. To investigate the matrix effects on the analyte signal, spike experiments were performed using chamomile tea extracts and good recovery results were obtained between 85.7 and 113.8%. A 57.8-fold improvement was achieved in the detection power compared to that of a conventional FAAS system. The results obtained throughout all experimental studies demonstrated the applicability in addition to the accuracy of the method for the quantification of trace levels of cobalt with high accuracy in a chamomile tea matrix.

Introduction:VNS is an adjunctive neuromodulation therapy for patients with drug-refractory epilepsy. The antiseizure effect of VNS is thought to be related to a diffuse modulation of functional connectivity but remains to be confirmed.Aim:To investigate electroencephalographic (EEG) metrics of functional connectivity in patients with drug-refractory epilepsy treated by vagus nerve stimulation (VNS), between VNS-stimulated “ON” and nonstimulated “OFF” periods and between responder (R) and nonresponder (NR) patients.Methods:Scalp-EEG was performed for 35 patients treated by VNS, using 21 channels and 2 additional electrodes on the neck to detect the VNS stimulation. Patients were defined as VNS responders if a reduction of seizure frequency of ∼50% was documented. We analyzed the synchronization in EEG time series during “ON” and “OFF” periods of stimulation, using average phase lag index (PLI) in signal space and phase-locking value (PLV) between 10 sources. Based on graph theory, we computed brain network models and analyzed minimum spanning tree (MST) for responder and nonresponder patients.Results:Among 35 patients treated by VNS for a median time of 7 years (range 4 months to 22 years), 20 were R and 15 were NR. For responder patients, PLI during ON periods was significantly lower than that during OFF periods in delta (p= 0.009), theta (p= 0.02), and beta (p= 0.04) frequency bands. For nonresponder patients, there were no significant differences between ON and OFF periods. Moreover, variations of seizure frequency with VNS correlated with the PLI OFF/ON ratio in delta (p= 0.02), theta (p= 0.04), and beta (p= 0.03) frequency bands. Our results were confirmed using PLV in theta band (p< 0.05). No significant differences in MST were observed between R and NR patients.Conclusion:The correlation between VNS-induced interictal EEG time-series desynchronization and decrease in seizure frequency suggested that VNS therapeutic impact might be related to changes in interictal functional connectivity.Impact statementElectroencephalography (EEG) desynchronization has been proposed to be a mechanism for antiepileptic effect of vagus nerve stimulation (VNS). We measured interictal EEG time-series synchronization during stimulated (ON) and nonstimulated (OFF) periods in epileptic patients treated by VNS. Phase lag index differences between ON and OFF periods were measured in delta, theta, and beta bands only in responder patients. To our knowledge, our study is the first to statistically correlate interictal cortical desynchronization during ON periods with reduction in seizure frequency. Our result supports the hypothesis that the antiseizure effect of VNS is mediated by cortical desynchronization.

Nanostructure incorporation into devices plays a key role in improving performance, yet processes for preparing two-dimensional (2D) arrays of colloidal nanoparticles tend not to be universally applicable, particularly for soft and oxygen-sensitive substrates for organic and perovskite-based electronics. Here, we show a method of transferring reverse micelle-deposited (RMD) nanoparticles (perovskite and metal oxide) on top of an organic layer, using a functionalized graphene carrier layer for transfer printing. As the technique can be applied universally to RMD nanoparticles, we used magnetic (γ-Fe2O3) and luminescent (methylammonium lead bromide (MAPbBr3)) nanoparticles to validate the transfer-printing methodology. The strong photoluminescence from the MAPbBr3under UV illumination and high intrinsic field of the γ-Fe2O3as measured by magnetic force microscopy (MFM), coupled with Raman measurements of the graphene layer, confirm that all components survive the transfer-printing process with little loss of properties. Such an approach to introducing uniform 2D arrays of nanoparticles onto sensitive substrates opens up new avenues to tune the device interfacial properties.

It was 8 p.m. on Christmas Eve and I was waiting for Mass to begin. This was my third Christmas retreat at Mepkin Abbey, which sits on 3,132 acres shaded [...]

Dysembryoplastic neuroepithelial tumors and gangliogliomas are developmental glioneuronal tumors usually revealed by partial epilepsy. High epileptogenicity, childhood epilepsy onset, drug-resistance, temporal location, and seizure freedom after complete resection are common characteristics of both tumors. We report the specificity of surgical management, functional results and seizure outcome in cases of a tumor location in eloquent areas.

In this study, we assess the utility of a normal force (pull-test) approach to measuring adhesion in organic solar cells and organic light-emitting diodes. This approach is a simple and practical method of monitoring the impact of systematic changes in materials, processing conditions, or environmental exposure on interfacial strength and electrode delamination. The ease of measurement enables a statistical description with numerous samples, variant geometry, and minimal preparation. After examining over 70 samples, using the Weibull modulus and the characteristic breaking strength as metrics, we were able to successfully differentiate the adhesion values between 8-tris(hydroxyquinoline aluminum) (Alq3) and poly(3-hexyl-thiophene) and [6,6]-phenyl C61-butyric acid methyl ester (P3HT:PCBM) interfaces with Al and between two annealing times for the bulk heterojunction polymer blends. Additionally, the Weibull modulus, a relative measure of the range of flaw sizes at the fracture plane, can be correlated with the roughness of the organic surface. Finite element modeling of the delamination process suggests that the out-of-plane elastic modulus for Alq3is lower than the reported in-plane elastic values. We suggest a statistical treatment of a large volume of tests be part of the standard protocol for investigating adhesion to accommodate the unavoidable variability in morphology and interfacial structure found in most organic devices.

A new reversed-phase ultraperformance liquid chromatography method with a photodiode array detector was developed for the quantification of ascorbic acid (AA) and caffeine (CAF) in 11 different commercial drinks consisting of one energy drink and 10 ice tea drinks. Separation of the analyzed AA and CAF with an internal standard, caffeic acid, was performed on a Waters BEH C18column (100 mm × 2.1 mm, 1.7 μm i.d.), using a mobile phase consisting of acetonitrile and 0.2M H3PO4(11:89, v/v) with a flow rate of 0.25 mL/min and an injection volume of 1.0 μL. Calibration graphs for AA and CAF were computed from the peak area ratio of AA/internal standard and CAF/internal standard detected at 244.0 nm and 273.6 nm, respectively. The developed reversed-phase ultraperformance liquid chromatography method was validated by analyzing standard addition samples. The proposed reversed-phase ultraperformance liquid chromatography method gave us successful results for the quantitative analysis of commercial drinks containing AA and CAF substances.

We report our investigation of the chemical doping mechanism induced by LiF interaction with fullerene thin films. High resolution X-ray photoelectron spectroscopy of the C1s shake-up satellites and F1s main core level, supported by density functional calculations, suggest the formation of a charge transfer complex between covalent LiF monomers and dimers and C60. This interaction was observed in both LiF/C60 and C60/LiF depositions, suggesting that some charge transfer complexation can occur in these systems even without dissociation.

Polymer templated nanoparticles, such as diblock copolymer templated, are an interesting avenue for improvement of thin-film optical devices by the modification of interfaces between different layers. The existence of insulating polymer is a challenge to the applications of templated nanoparticles and this paper addresses that by assessing the effectivity of gas plasmas in the removal of polymer from a thin film of loaded diblock copolymer reverse micelles to produce iron oxide nanoparticles. Using Raman spectroscopy, we have described a method, that can be used to evaluate polymer removal effectivity that can be employed for different systems, and was used to quantify other polymer removal methods such as UV/Ozone exposure and Electron bombardment. We found that a mixture of reactive ion etching and ionic bombardment is highly effective for oxide materials and can be accomplished by leaking air in pure gas plasmas.

Targeted deletion of BAFF causes severe deficiency of splenic B cells. BAFF-R is commonly thought to signal to nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB)–inducing kinase dependent noncanonical NF-κB RelB. However, RelB-deficient mice have normal B-cell numbers. Recent studies showed that BAFF also signals to the canonical NF-κB pathway, and we found that both RelB and cRel are persistently activated, suggesting BAFF signaling coordinates both pathways to ensure robust B-cell development. Indeed, we report now that combined loss of these 2 NF-κB family members leads to impaired BAFF-mediated survival and development in vitro. Although single deletion of RelB and cRel was dispensable for normal B-cell development, double knockout mice displayed an early B-cell developmental blockade and decreased mature B cells. Despite disorganized splenic architecture in Relb−/−cRel−/− mice, generation of mixed-mouse chimeras established the developmental phenotype to be B-cell intrinsic. Together, our results indicate that BAFF signals coordinate both RelB and cRel activities to ensure survival during peripheral B-cell maturation.

Several current data indicate that intracranial records of the Bereitschaftspotential from some brain loci manifest baseline shifts (EBS) in the early pre-movement period that are separated from the movement components by a distinct plateau. In this context, main purpose of this study was to assess whether structures generating the EBSs that are simultaneously widespread in various structures of the brain will be specifically linked to higher levels of large-scale integration in comparison to structures that were not involved in EBS generation. In this study were included 21 epilepsy surgery candidates (12 men, 9 women; aged from 18 to 49 years), who were measured during self-paced clenching movements of the hand. Brain activities during the task were recorded using intracerebral electrodes and were evaluated in pairs. Eighty two percent of the EBSs started in various distant brain structures at the same time, eighteen percent at different time. Approximately half of the EBSs of the first group started in the prefrontal regions; the second half was obtained from pairs located in parietal and temporal regions. The first, the second, and the third groups exhibited a special degree of activity synchronization. The simultaneous EBS onsets associated synchronization strongly suggests significantly higher functional coupling of these brain areas which is supposed to be a basic mechanism of integration of various areas of the brain participating in cognitive and intentional functions.

Here we present the fabrication of polypyrrole (PPy) surfaces with a controlled overhang structure. Regularly structured PPy films were produced using interfacial polymerization around a sacrificial crystalline colloidal monolayer at the air/water interface. The morphology of the final inverse colloidal PPy film is controlled by the amount of monomer, the monomer: oxidant ratio and polymerization time. The PPy films exhibit an overhang structure due to depth of particle immersion in the water phase. As a result of the overhang structure, the PPy films are made hydrophobic, although the material itself is hydrophilic. The apparent contact angle of water on the structured surfaces is 109.5°, which is in agreement with the predicted contact angle using the Cassie–Baxter equation for air-filled cavities. This fabrication technique is scalable and can be readily extended to other systems where controlled wettability is required.

IMPORTANCE: Previous studies have indicated a heritable component of the etiology of neurodegenerative diseases such as Alzheimer disease (AD), frontotemporal dementia (FTD), and progressive supranuclear palsy (PSP). However, few have examined the contribution of low-frequency coding variants on a genome-wide level. OBJECTIVE: To identify low-frequency coding variants that affect susceptibility to AD, FTD, and PSP. DESIGN, SETTING, AND PARTICIPANTS: We used the Illumina HumanExome BeadChip array to genotype a large number of variants (most of which are low-frequency coding variants) in a cohort of patients with neurodegenerative disease (224 with AD, 168 with FTD, and 48 with PSP) and in 224 control individuals without dementia enrolled between 2005-2012 from multiple centers participating in the Genetic Investigation in Frontotemporal Dementia and Alzheimer’s Disease (GIFT) Study. An additional multiancestral replication cohort of 240 patients with AD and 240 controls without dementia was used to validate suggestive findings. Variant-level association testing and gene-based testing were performed. MAIN OUTCOMES AND MEASURES: Statistical association of genetic variants with clinical diagnosis of AD, FTD, and PSP. RESULTS: Genetic variants typed by the exome array explained 44%, 53%, and 57% of the total phenotypic variance of AD, FTD, and PSP, respectively. An association with the known AD gene ABCA7 was replicated in several ancestries (discovery P = .0049, European P = .041, African American P = .043, and Asian P = .027), suggesting that exonic variants within this gene modify AD susceptibility. In addition, 2 suggestive candidate genes, DYSF (P = 5.53 × 10−5) and PAXIP1 (P = 2.26 × 10−4), were highlighted in patients with AD and differentially expressed in AD brain. Corroborating evidence from other exome array studies and gene expression data points toward potential involvement of these genes in the pathogenesis of AD. CONCLUSIONS AND RELEVANCE: Low-frequency coding variants with intermediate effect size may account for a significant fraction of the genetic susceptibility to AD and FTD. Furthermore, we found evidence that coding variants in the known susceptibility gene ABCA7, as well as candidate genes DYSF and PAXIP1, confer risk for AD.

BAFF, an activator of the noncanonical NFκB pathway, provides critical survival signals during B cell maturation and contributes to B cell proliferation. We found that the NFκB family member RelB is required ex vivo for B cell maturation, but cRel is required for proliferation. Combined molecular network modeling and experimentation revealed Nfkb2p100 as a pathway switch; at moderate p100 synthesis rates in maturing B cells, BAFF fully utilizes p100 to generate the RelB:p52 dimer, whereas at high synthesis rates, p100 assembles into multimeric IκBsome complexes, which BAFF neutralizes in order to potentiate cRel activity and B cell expansion. Indeed, moderation of p100 expression or disruption of IκBsome assembly circumvented the BAFF requirement for full B cell expansion. Our studies emphasize the importance of p100 in determining distinct NFκB network states during B cell biology, which causes BAFF to have context-dependent functional consequences.

L’efficacité du traitement chirurgical des épilepsies partielles pharmaco-résistantes (EPPR) sur le contrôle des crises et la qualité de vie est aujourd’hui bien établie. La sélection des candidats repose sur les données cliniques, électrophysiologiques et sur l’imagerie. Celle-ci permet d’identifier les principales étiologies des EPPR curables par la chirurgie : la sclérose hippocampique, responsable de la majorité des épilepsies mésio-temporales, les tumeurs de bas grade d’origine développementale – DNTs et gangliogliomes – les dysplasies corticales focales, les lésions vasculaires et cicatricielles. Un bilan préchirurgical comprenant vidéo-EEG, imagerie anatomique et fonctionnelle, évaluation neuropsychologique et psychiatrique, effectué dans un centre de référence, confirme l’indication et évalue les risques de la chirurgie. Dans certains cas, une implantation d’électrodes intracérébrales pour enregistrement EEG invasif (SEEG) est nécessaire pour identifier la localisation et l’étendue de la région cérébrale responsable des crises et définir la stratégie chirurgicale. Les techniques chirurgicales se sont diversifiées et comprennent les interventions de résection–temporale, extra-temporale, en région fonctionnelle –, les interventions de destruction focale, de déconnexion et de neuromodulation. La prise en charge postopératoire est pluridisciplinaire et comprend la gestion du traitement antiépileptique, le traitement des comorbidités, l’aide à la réinsertion. Les résultats de la chirurgie sur les crises d’épilepsie dépendent avant tout de l’étiologie : la suppression des crises est observée chez 60 % à 80 % des patients dans l’épilepsie mésio-temporale, chez plus de 80 % des patients après résection tumorale et dans plus de 90 % des patients opérés d’une dysplasie corticale focale. La guérison des crises est suivie d’une amélioration significative de la qualité de vie. Le déclin de la mémoire après intervention sur le lobe temporal peut être prédit sur des données cliniques et d’imagerie fonctionnelle. D’autres défis demeurent à relever, dont la réduction des délais d’accès à la chirurgie, l’amélioration des résultats dans l’épilepsie mésio-temporale et l’identification pré- et intra-opératoire des lésions épileptogènes non visibles sur l’imagerie.

The neutrophil-to-lymphocyte ratio is an independent predictor of worse prognosis in both infectious and cardiovascular disease. We hypothesized that an increased neutrophil-to-lymphocyte ratio at admission would predict in-hospital unfavourable outcomes in patients with infective endocarditis (IE).

Metabolic syndrome (MetS) is a strong predictor of cardiovascular events and coronary flow reserve (CFR), an indicator of microvascular function, has been found to be impaired in MetS. Epicardial fat thickness (EFT) reflects visceral adiposity and is considered an important cardiometabolic marker. In this study, we aimed to examine the presence of an association between CFR and EFT in MetS patients.

To determine optimal resections in the 3 dysembryoplastic neuroepithelial tumor (DNT) histologic subtypes (simple, complex, and nonspecific) based on MRI features.

Model donor–acceptor assemblies at metal–organic interfaces, namely, fluorinated copper-phthalocyanines (F16CuPC) and pentacene (PEN) assemblies on the Au(111) surface, have been the focus of the present study. A full picture of the crystallographic and electronic structure of PEN and F16CuPC monolayers as well as of their 1:1 binary mixture on the Au(111) surface has been explored by means of a variety of surface-sensitive techniques, providing important information on the intermolecular and molecule–substrate interactions governing the self-assembly process. A long-range ordered donor–acceptor network is observed for the mixture as a result of the greatly enhanced intermolecular interaction via C–F···H–C hydrogen bonds. Interestingly, the new supramolecular structure involves changes in the electronic structure of the molecular components. In particular, the strongest changes are observed at the C and F atoms of the F16CuPc, as opposed to the F16CuPc N, Cu, or PEN C atoms. With the aid of theoretical calculations, such effects are found to be at least partially related to an upward shift in energy of the F16CuPc molecular orbitals, concomitant with a molecule-to-metal charge donation, not from the HOMO, but deeper lying orbitals.

Interfaces are inherent in and essential to organic electronic devices. At every interface, both organic/organic and organic/inorganic, the potential to utilize nanostructuring to control device performance is very high. In this paper, we focus on one example of nanostructuring at the donor/acceptor heterojunction in organic photovoltaics, with the purpose of modifing efficiency by four orders of magnitude. We show that the length of the exciton dissociating interface can be tuned by changing the substrate temperature for small molecule heterojunction photodiodes based on crystalline DIP/C60 mixtures. Due to the tuneable interface morphology, the performance of such devices can be changed from poor performing planar heterojunctions to higher efficiency ordered nanoscale bulk heterojunction structures. In this way, highly crystalline DIP can be thought of as a natural “bulk” heterojunction.

To determine the diagnostic accuracy and prognostic value of 18FDG-PET in a recent series of patients operated for intractable partial epilepsy associated with histologically proven Taylor-type focal cortical dysplasia (TTFCD) and negative MRI.

In this combined atomic force microscopy and X-ray diffraction study, we explore the microscopic origin of the scaling properties of the growth of organic−organic heterostructures formed here by F16CoPc and diindenoperylene (DIP) molecules as representative systems for electron and hole transporting materials. We evaluate the influence of the morphological properties of the first organic layer (DIP) on further temporal evolution of the morphology and structure of F16CoPc films. From the derived scaling exponents, we conclude that the morphology evolution is dominated by mound formation. The microscopic origin of such morphology is ascribed to structural changes occurring during the first stages of F16CoPc growth as revealed by grazing incidence X-ray diffraction (GIXD). The microstructure of organic materials should be taken into account, the challenging task of modeling growing surfaces and interfaces of organic materials.

By a combined AFM/X-ray study, we unveil a reconstruction at the organic interface accompanying the Stranski−Kranstanov growth of di-indenoperylene (DIP) deposited on fluorinated cobalt-phthalocyanines (F16CoPc). This reconstruction involves an abrupt change in the F16CoPc packing in those areas covered by DIP. After the total completion of the first DIP monolayer, the entire F16CoPc interfacial layer is reconstructed and eventually becomes buried under the growing DIP film. We demonstrate that the morphological transition from smooth to highly textured heterostructures occurring at a threshold temperature of 70 °C is intimately related to the thermal activation of the reconstruction of the underlying F16CoPc layers. This study provides further understanding of the molecular-scale processes that ultimately determine the controlled growth of organic heterojunctions.

Interfaces are inherent in and essential to organic electronic devices. At every interface, both organic/organic and organic/inorganic, the potential to utilize nanostructuring to control device performance is very high. In this paper, we focus on one example of nanostructuring at the donor/acceptor heterojunction in organic photovoltaics, with the purpose of modifing efficiency by four orders of magnitude. We show that the length of the exciton dissociating interface can be tuned by changing the substrate temperature for small molecule heterojunction photodiodes based on crystalline DIP/C60 mixtures. Due to the tuneable interface morphology, the performance of such devices can be changed from poor performing planar heterojunctions to higher efficiency ordered nanoscale bulk heterojunction structures. In this way, highly crystalline DIP can be thought of as a natural “bulk” heterojunction.

To test the hypothesis that extratemporal neuronal networks are involved in dystonic posturing (DP) observed in mesial temporal epilepsy (MTLE).

Patients with Taylor’s type focal cortical dysplasia (FCD) present with seizures that are often medically intractable. Here, we attempted to identify the cellular and pharmacological mechanisms responsible for this epileptogenic state by using field potential and K+‐selective recordings in neocortical slices obtained from epileptic patients with FCD and, for purposes of comparison, with mesial temporal lobe epilepsy (MTLE), an epileptic disorder that, at least in the neocortex, is not characterized by any obvious structural aberration of neuronal networks. Spontaneous epileptiform activity was induced in vitro by applying 4‐aminopyridine (4AP)‐containing medium. Under these conditions, we could identify in FCD slices a close temporal relationship between ictal activity onset and the occurrence of slow interictal‐like events that were mainly contributed by GABAA receptor activation. We also found that in FCD slices, pharmacological procedures capable of decreasing or increasing GABAA receptor function abolished or potentiated ictal discharges, respectively. In addition, the initiation of ictal events in FCD tissue coincided with the occurrence of GABAA receptor‐dependent interictal events leading to [K+]o elevations that were larger than those seen during the interictal period. Finally, by testing the effects induced by baclofen on epileptiform events generated by FCD and MTLE slices, we discovered that the function of GABAB receptors (presumably located at presynaptic inhibitory terminals) was markedly decreased in FCD tissue. Thus, epileptiform synchronization leading to in vitro ictal activity in the human FCD tissue is initiated by a synchronizing mechanism that paradoxically relies on GABAA receptor activation causing sizeable increases in [K+]o. This mechanism may be facilitated by the decreased ability of GABAB receptors to control GABA release from interneuron terminals.

Interictal hypometabolism is commonly found in mesio‐temporal lobe epilepsy (MTLE), but its pathophysiology remains incompletely understood. We hypothesized that metabolic changes reflect the preferential networks involved by ictal discharges. We analysed the topography of interictal hypometabolism according to electro‐clinical patterns in 50 patients with unilateral hippocampal sclerosis (HS) and consistent features of MTLE. Based on electro‐clinical correlations, we identified four groups: (i) mesial group (13 cases) characterized by mesial seizure onset without evidence of early spread beyond the temporal lobe; (ii) anterior mesio‐lateral group (AML; 18 cases) with early anterior spread involving the anterior lateral temporal cortex and insulo‐fronto‐opercular areas; (iii) widespread mesio‐lateral group (WML; 15 cases) with wide spread (involving both anterior and posterior lateral temporal and perisylvian areas); and (iv) bitemporal (BT) group (four cases) with early contralateral temporal spread. Results of [18F]fluorodeoxyglucose‐PET imaging in each group were compared with those of 10 control subjects using statistical parametric mapping software (SPM99). MRI data and surgical outcome in each group were compared with metabolic findings. Hypometabolism was limited to hippocampal gyrus, temporal pole and insula in the mesial group. Gradual involvement of lateral temporal cortex, insula and perisylvian areas was observed in the AML and WML groups. The BT group differed from the others with mild bitemporal involvement, bilateral insular hypometabolism and longer epilepsy duration. MRI structural abnormalities outside of the mesial formations were detected in 65% of the cases. Neither the severity of HS nor temporal atrophy appeared related to the topography of hypometabolism. However, temporal hypometabolism was more extended when temporo‐polar signal changes were detected. Among operated patients (n = 43), seizure‐free outcome was obtained in 82%. Surgical outcome appeared more favourable in the mesial group. However, the difference between the four groups was not significant. Our results suggest that hypometabolism in MTLE may be related to ictal discharge generation and spread pathways, even if structural changes and epilepsy duration may also play a role.

Focal cortical dysplasia (FCD) is an increasingly recognized cause of intractable epilepsy. Surgical data suggest that the dysplastic cortex should be removed to obtain freedom from seizures, but the prognosis remains poor as FCD is difficult to delineate by imaging. We retrospectively analysed a series of 28 patients (aged 5-41 years, median 16.5 years) with FCD who had been investigated by stereoelectroencephalography (SEEG) between 1964 and 1995. Neurophysiological data were correlated with histological findings and surgical outcome. MRI was available for only seven patients. Severe partial epilepsy of early onset, pre-existing neurological deficit (68%) and cognitive impairment were the main clinical features. FCD was distributed equally between all lobes except for the temporal lobe, and was found predominantly on the mesial aspect of the cerebral hemispheres. SEEG findings provided evidence of dysplastic tissue epileptogenicity, as demonstrated by intralesional rhythmic spike discharges, the onset of ictal discharges and a low epileptogenic threshold. The epileptogenic zone corresponded to histologically defined FCD in 82% of the cases. Despite the lack of adequate neuroimaging in most cases, 64% of the patients became seizure-free after surgery. The main predictors of a favourable outcome were complete removal of the epileptogenic zone (P< 0.01) and complete removal of the dysplastic cortex (P< 0.01). These results emphasize the usefulness of neurophysiological data in accurately assessing the extent of the FCD.