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A comparative analysis of the targets for deep brain stimulation (DBS) to treat refractory temporal lobe epilepsy and the rationale for its use is presented, with an emphasis on the latency to obtain the significant antiepileptic effect and the long-term seizure control. The analysis includes consideration of surgical techniques currently used to optimize antiseizure effects and decrease surgical risks. Seizure control is similar for programed DBS and DBS responsive to abnormal cortical or subcortical electroencephalogram (EEG) activity. There is no difference in the long-term seizure control between programmed and responsive and intermittent or continuous DBS. However, intermittent programed DBS may have a significant antiseizure effect starting in the first month when applied to a non-sclerotic tissue such as the parahippocampal cortex. DBS induces no neuropsychological deterioration.

This paper presents a multi-agent system that is able to search people on a database of images recognizing patterns of facial features on each person, based on the main features of the face (eyes, nose and mouth). Using that multi-agent architecture, the system can do the work faster applying Fisherfaces algorithm for the face recognition and classification. This technology can be used for several purposes like specific ads in each user group to suit better their interests or search for the age and gender of people that usually go to different places like malls or shops.

OBJECTIVE The authors sought to determine the antiseizure effects of deep brain stimulation (DBS) of the parahippocampal cortex (PHC) for treatment of drug-resistant mesial temporal lobe epilepsy (MTLE). METHODS After a 3-month baseline period, 6 adult patients with drug-resistant MTLE and hippocampal sclerosis (HS) had stereoelectroencephalography (SEEG)–DBS electrodes implanted at the PHC for identification of the seizure onset zone (SOZ). Patients entered an 8-month, randomized, double-blind protocol for DBS, followed by a 12-month open-phase study. Monthly reports of seizure frequency were collected, with separate counting of focal seizures with or without awareness impairment (focal impaired awareness seizures [FIAS] or focal aware seizures [FAS], respectively) and focal evolving to bilateral generalized tonic clonic seizures (GTCS). Stimulation parameters were 130 Hz, 450 μsec, 2.5–3 V, and cyclic stimulation 1 minute on/4 minutes off. RESULTS The total seizure rate decrement during follow-up was 41% (CI 25%–56%), with better seizure control for GTCS (IQR 19%–20%) and FIAS (IQR 0%–16%), with FAS being less responsive (IQR 67%–236%). No neuropsychological deterioration was observed. CONCLUSIONS PHC DBS induced important antiseizure effects in patients with incapacitating FIAS and GTCS, most likely through blocking the propagation of hippocampal-onset seizures. The PHC target can be easily and safely approached due to positioning away from vascular structures, and there was no evidence of DBS-induced cognitive deterioration.

Public agencies or owners that are responsible for the construction and maintenance of built infrastructure or facilities are working toward the digitalization of the project administration...

To assess the time-variant performance of RC structures, it is important to model the various deterioration processes as well as their interactions in addition to the associated uncertainti...

Myelodysplastic syndromes present with a range of cytogenetic abnormalities that are used to guide diagnosis and management of the disease. Herein, we present the case of a 72-year-old female patient who presented with pancytopenia. Peripheral blood showed Hb 9.0 g/dl, neutrophils less than 1800/mm3, and platelets less than 100,000/mm3. Bone marrow showed erythroid hyperplasia, megaloblastic changes, dyserythropoiesis, multinuclearity, nuclear bridges, nuclear budding, atypical mitoses, and ring sideroblasts. Also, CD34 and CD117 as well as myeloperoxidase positive populations were present. On this basis, a diagnosis of myelodysplastic syndrome was rendered. Chromosome studies showed an abnormal female karyotype with an isochromosome 17q as well as deletion 20q in 17 of the 20 metaphase cells examined. The remaining three cells were cytogenetically normal. Molecular cytogenetic studies using a TP53-specific probe showed only one TP53 signal in 87% of the nuclei examined. An i(17q) as a sole cytogenetic aberration is rare among both MDS and myeloid malignancies in general, but is functionally similar to aberrations of 17p that lead to loss of TP53. This case provides further insight into the spectrum of cytogenetic abnormalities present in MDS.

The chloride content analysis of the concrete exposed to chlorides often shows an initial increase in the concentration of chlorides to a maximum point within the first layers from the concrete surface, followed by a gradual reduction in the concentration of chlorides at the lower depths. A review of literature shows that very little attention has been given to the depth (Δx) at which the maximum chloride concentration (Cmax) occurs and its potential impacts on the numerical estimation of the apparent chloride diffusion coefficient (Da) and surface chloride concentration (Cs). This paper studies the influence of water-to-cement ratio (w/c), the concentration of chlorides in the environment, the time-to-exposure, and exposure duration on Cmax and Δx. Results show that w/c does not have a significant influence on Cmax. However, a significant increase in Δx is observed with an increase in the w/c. Results also show that while Cmax has time-variant properties and it increases nonlinearly with the exposure duration, exposure duration has minimal impacts on Δx. In addition, the time-to-exposure and the concentration of chlorides in the exposure environment are found to be significant factors influencing both Cmax and Δx. The findings of this study show that Δx has a significant impact on the numerical estimation of Da and Cs. Because Δx is not limited to the first millimeter of the concrete surface, as specified in ASTM C1556 , care must be taken to exclude the layers that correspond to Δx.

The binding of admixed chlorides in the concrete can delay the corrosion of reinforcing steel and extend the service life of reinforced concrete structures. Although extensive research has been conducted to study the chloride binding capacity of cementitious systems subject to external chlorides, there is little information available on the chloride binding capacity of cementitious systems containing admixed chlorides. In this paper, the chloride binding capacity of several cementitious systems containing ordinary portland cement (OPC), Type C and F fly ashes, slag, and silica fume with different replacement levels is studied using acid-soluble, water-soluble, and pore-pressed testing procedures. In addition, the influence of water-to-binder ratio and admixed chloride levels on the percentages of bound chlorides is explored and discussed. The experimental results indicate that, on average, the concentration of pore-pressed chlorides is significantly lower than the concentration of water-soluble chlorides. Furthermore, the estimated bound chlorides using the pore-pressed chlorides are significantly higher than the bound chloride estimated using water-soluble chlorides. Results show that the Langmuir isotherm can be used to explain the relationship between free and bound chlorides in OPC paste samples containing admixed chlorides. Results of this study also suggest that chloride testing procedures can be very influential in quantifying the concentration of bound chlorides. Therefore, there is a need to standardize the process used for measuring the chlorides in cementitious systems for assessing chloride binding.

Objective The purpose of this study was to evaluate the relation between cognitive performance and white matter (WM) integrity in patients with temporal lobe epilepsy (TLE) with mesial temporal sclerosis (MTS). Methods We included 26 patients with TLE (10 right, 16 left onset) as well as 24 healthy controls matched for age, gender, and years of education. In addition to quantitative hippocampal volume and transverse relaxation (T2) evaluation, whole-brain WM was analyzed using fractional anisotropy (FA) maps, derived from the diffusion tensor model. Average FA values were obtained from 38 regions of interest (ROI) of the main WM fascicles using an atlas-based approach. All subjects underwent extensive coFignitive assessments, Wechsler Adult Intelligence Scale (WAIS-IV) and Wechsler Memory Scale (WMS-IV). Fractional anisotropy was correlated with neuropsychological scores, and group effects were evaluated. Finally, patients were clustered based on their cognitive performance to evaluate if clinical and structural variables relate to specific cognitive profiles. Results Patients had differential alterations in the integrity of the WM dependent on seizure laterality and presence of hippocampal sclerosis. Patients with TLE showed, on average, lower scores in most of the cognitive assessments. Correlations between cognition and WM followed specific trajectories per group with TLE, particularly in Left-TLE, in which we found a marked association between cognitive abilities and WM abnormalities. Cluster analysis of cognitive performance revealed three cognitive profiles, which were associated with the degree and spread of WM abnormalities. Significance White matter diffusion characteristics differ between patients, particularly in relation to seizure laterality and hippocampal damage. Moreover, WM abnormalities are associated with cognitive performance. The extent of WM alterations leads to disrupted cerebral intercommunication and therefore negatively affects cognition.

Significant research has been conducted to assess the amount of chlorides that results in corrosion initiation, C T , and propagation of the embedded reinforcing steel in concrete. However,...

Current service life models for predicting the time to chloride-induced corrosion initiation of steel reinforcement in concrete structures are based on a hypothesized surface chloride concentration, Cs, as a boundary condition. This is either assumed to be constant or varies with time, generally disregarding other factors that influence Cs. For example, Fickian models use a constant Cs and existing time-variant models assume Cs is only a function of time. In this paper, an improved time-variant Cs model is hypothesized using general physical concepts and is then validated by an empirical study. The proposed model, as opposed to the existing time-variant models, not only accounts for the variability of Cs with exposure time but also incorporates the effects of time to exposure and the effects of the concentration of chlorides in the exposure environment. The model assumes that Cs is sigmoidal in shape with an asymptote that is a function of the concentration of chlorides in the environment. The input variables for the proposed model were selected based on best subset sampling analysis on the results of the experimental work to determine the influence of water-to-cement ratio, time to exposure, the concentration of chlorides in the exposure environment, and exposure time on Cs. The accuracy of the proposed model is assessed versus existing time-variant Cs models and the results indicate that the proposed model better predicts the Cs in concrete exposed to chlorides. Moreover, results of service life predictions using the proposed model show that the proposed model yields more accurate results, better protecting owners from financial and engineering risks.

This research investigated the synergistic effects of fly ash and aggregate reactivity on chloride transport and time to corrosion. Specimens containing fly ash replacement levels of 0, 20, and 40% by weight with and without reactive aggregate were exposed to wetting/drying cycles. Expansion, corrosion potential, and macrocell current were measured monthly until corrosion of the embedded reinforcement initiated. The results indicate that inclusion of fly ash in specimens containing non-reactive aggregate results in lower apparent diffusion coefficient values ( D a ) and lower critical chloride threshold values ( C T ) in concrete. The benefits from the lower D a values are more significant than the disbenefits from the reduction in C T when assessing time to corrosion initiation. Specimens containing reactive aggregate and 20% fly ash exhibited longer times to corrosion initiation than specimens containing 40% fly ash. Results indicate that the ASR gel resists the transport of chlorides and the formation of small amounts of ASR gel in the specimens containing 20% fly ash reactive aggregate results in slower transport rates and longer times to corrosion initiation.

Chloride induced corrosion in concrete is a well-known issue. Although numerous researchers have attempted to quantify the chloride threshold limits (CT) in different concrete systems (with little consensus), the issue of allowable admixed chlorides (CA) in concrete is still very much unresolved. For example, The CA limits specified by the American Concrete Institute (ACI) committees range from 0.06 to 1 percent by the weight of cement or cementitious materials. Similarly, the CA limits published by the State Highway Agencies in the U.S. vary significantly from one State to another (up to 9000 times difference). These significant differences and the variability in the published CA values can have significant economic and engineering risks. Therefore, it is essential that a standardized approach be developed to minimize these risks. The objective of the present study is to introduce a framework to remove subjectivity and variability in the decision-making process regarding CA. This paper provides a description of the development of the framework and economic assessment of selecting CA based on the first-order reliability method (FORM), spatial modeling techniques, and quantitative decision making tools. The proposed framework would help policy and decision makers realize the significant influence of CA on the corrosion of reinforcing steel in concrete and life-cycle cost of a project, and ultimately assisting them in making unbiased decisions that have scientific underpinnings.

Ionic transport in concrete can be described using the formation factor, which is the ratio of the resistivity of the concrete and the pore solution resistivity. The pore solution resistivity may be assumed, directly measured, or computed from the pore solution composition. This paper describes an experimental investigation aimed at determining the feasibility of using X-ray fluorescence (XRF) to obtain the alkali concentrations of the pore solution which enable the calculation of pore solution resistivity. In order to do this, simulated pore solutions containing known amounts of sodium and potassium were prepared and analyzed using XRF. XRF was performed on two sample types: (1) the simulated solutions and (2) beads where the water from the solution is evaporated and the remaining material is fused using a fluxing agent. The compositions obtained experimentally from XRF are compared to known compositions to demonstrate the accuracy of the technique. In addition, the measured simulated pore solution resistivity was compared to the simulated pore solution resistivity calculated from XRF measurements. The results indicate that the composition had an average error of 0.50% while the estimated simulated pore solution resistivity had an average error of 10.95%. The results of this study indicate that XRF has the potential to be an alternative to the time consuming methods currently used to measure the composition of the pore solution.

Experience has shown that many aspects of experimental design for studying steel corrosion in cementitious systems may significantly influence the obtained results. In the absence of standardized methods to study steel corrosion in concrete, researchers usually define their own test setups, which partially explains the large scatter and uncertainty in the aggregated published data. When the details of these setups are not provided adequately, experimental results cannot be interpreted in a wider context. Unfortunately, many scientific publications lack important experimental details. Therefore, this paper aims at improving the quality of reported experimental details, observations, and data in scientific publications, and raising awareness for relevant issues to improve the quality of research in the field. To this end, this paper provides a list of experimental details that have been found important by many decades of research, and which are, thus, recommended to be considered in conducting and reporting laboratory studies involving corrosion of steel embedded in cementitious systems. Finally, we propose a c hecklist for reporting experimental data in scientific publications., RILEM Technical Letters, 4, ISSN:2518 -0231

The amygdaloid complex plays a crucial role in processing emotional signals and in the formation of emotional memories. Neuroimaging studies have shown human amygdala activation during rapid eye movement sleep (REM). Stereotactically implanted electrodes for presurgical evaluation in epileptic patients provide a unique opportunity to directly record amygdala activity. The present study analysed amygdala activity associated with REM sleep eye movements on the millisecond scale. We propose that phasic activation associated with rapid eye movements may provide the amygdala with endogenous excitation during REM sleep. Standard polysomnography and stereo-electroencephalograph (SEEG) were recorded simultaneously during spontaneous sleep in the left amygdala of four patients. Time-frequency analysis and absolute power of gamma activity were obtained for 250 ms time windows preceding and following eye movement onset in REM sleep, and in spontaneous waking eye movements in the dark. Absolute power of the 44-48 Hz band increased significantly during the 250 ms time window after REM sleep rapid eye movements onset, but not during waking eye movements. Transient activation of the amygdala provides physiological support for the proposed participation of the amygdala in emotional expression, in the emotional content of dreams and for the reactivation and consolidation of emotional memories during REM sleep, as well as for next-day emotional regulation, and its possible role in the bidirectional interaction between REM sleep and such sleep disorders as nightmares, anxiety and post-traumatic sleep disorder. These results provide unique, direct evidence of increased activation of the human amygdala time-locked to REM sleep rapid eye movements.

In Mexico and the United States of America (USA), a debate was recently opened on the use of some cannabis extracts as anticonvulsive drugs. Given the broad influence that social networks and the media have on the general population, it is worth highlighting the risk to the public of receiving erroneous information and forming opinions that may compromise their health. In light of this context, taxonomic and biochemical properties, the endocannabinoid system and the historical and legal context of cannabis were reviewed in order to provide a clear overview on the physiological and cultural impacts of cannabis extracts. Subsequently, pre-clinical models, clinical trials and ongoing studies evaluating some phytocannabinoids and synthetic cannabinoids as antiepileptic treatment were assessed. The obtained information was then subjected to interdisciplinary scrutiny and discussion. Taking into account that plantation and commercialisation of cannabis have been historically illegal in Mexico, the relative lack of evidence regarding its effects in humans and the ideas arising from the aforementioned, it is understandable that the medical community, as well as the general population, have reservations about its suitability as a treatment. Having developed a clinical neuroethics methodology, an interdisciplinary expert group discussion was coordinated in order to assess the benefits of the medical practice and limit the influence that healthcare professionals’ ethics could have on decision-making. This concluded with three proposals that portray the Hospital General de Mexico Epilepsy Clinic's position, while also contributing important considerations to the mature debate concerning the legalisation of cannabis.

Objective To determine the usefulness and efficacy of radiofrequency ablations (RFA) of the Centromedian thalamic nucleus (CMN) to control primarily generalized or multifocal seizures in refractory epilepsy. Methods Six patients with clinical diagnosis of multifocal or primarily generalized drug-resistant epilepsy were included. Bilateral RFA of the CMN was performed through a monopolar 1.8 mm. tip electrode with a temperature of 80 °C during 90 seconds. Patients were followed in every 3 months visit for 20 to 36 months and kept a monthly seizure count calendar. We also compared maximal paroxysmal electroencephalogram (EEG) activity and neuropsychological evaluation pre and 6 months postoperatively. Results A significant reduction in the number of generalized seizures was observed in all subjects in the range of 79–98%, starting the first post-operative month. Although focal aware seizures remained unchanged throughout follow-up, there was an important reduction on paroxysmal activity between the pre and postoperative EEG. No major changes on cognitive status were detected. There was post-operative dysphagia and odynophagia lasting one week and there was no mortality in this group of patients. Conclusion Preliminary results of CMN RFA suggest safety and a trend toward reduction of some seizure types, it may reduce the seizure frequency like other palliative procedures since the first post-operative month, but a larger, controlled study would be needed to establish the value of this therapy.