Suppression of Alfvén Modes on the National Spherical Torus Experiment Upgrade with Outboard Beam Injection.

In this Letter we present data from experiments on the National Spherical Torus Experiment Upgrade, where it is shown for the first time that small amounts of high pitch-angle beam ions can strongly suppress the counterpropagating global Alfvén eigenmodes (GAE). GAE have been implicated in the redistribution of fast ions and modification of the electron power balance in previous experiments on NSTX. The ability to predict the stability of Alfvén modes, and developing methods to control them, is important for fusion reactors like the International Tokamak Experimental Reactor, which are heated by a large population of nonthermal, super-Alfvénic ions consisting of fusion generated α's and beam ions injected for current profile control. We present a qualitative interpretation of these observations using an analytic model of the Doppler-shifted ion-cyclotron resonance drive responsible for GAE instability which has an important dependence on k_{⊥}ρ_{L}. A quantitative analysis of this data with the hym stability code predicts both the frequencies and instability of the GAE prior to, and suppression of the GAE after the injection of high pitch-angle beam ions.

Main-Ion Intrinsic Toroidal Rotation Profile Driven by Residual Stress Torque from Ion Temperature Gradient Turbulence in the DIII-D Tokamak.

Intrinsic toroidal rotation of the deuterium main ions in the core of the DIII-D tokamak is observed to transition from flat to hollow, forming an off-axis peak, above a threshold level of direct electron heating. Nonlinear gyrokinetic simulations show that the residual stress associated with electrostatic ion temperature gradient turbulence possesses the correct radial location and stress structure to cause the observed hollow rotation profile. Residual stress momentum flux in the gyrokinetic simulations is balanced by turbulent momentum diffusion, with negligible contributions from turbulent pinch. The prediction of the velocity profile by integrating the momentum balance equation produces a rotation profile that qualitatively and quantitatively agrees with the measured main-ion profile, demonstrating that fluctuation-induced residual stress can drive the observed intrinsic velocity profile.

Is a new sonic toothbrush more effective in plaque removal than a manual toothbrush?

AIM: Powered or manual toothbrushes are daily-used instrument in the Western area for the control and removal of bacterial biofilm. Among powered-toothbrushes, sonic technology has shown to produce fluid turbulent activity that might assist in plaque removal; however, limited knowledge is available in-vivo. The objectives of this study were to compare the plaque removal efficacy of two different toothbrushes in a population not familiar with sonic technology, and to collect and analyse data regarding oral hygiene habits. The null-hypothesis was that a sonic toothbrush is able to remove a superior amount of plaque compared to the manual type. MATERIALS AND METHODS: Forty young adult patients were enrolled in the study. A single-cohort crossover clinical trial was designed. For each patient, three appointments were scheduled: the first (T0) was used for oral care education and explanations of toothbrushes techniques, for a preliminary professional hygiene session, and for delivery of a questionnaire; at one week (T1), plaque evaluation was performed (Turesky modification of the Quigley and Hein index) at baseline and after asking patients to brush with the randomly selected manual or sonic device. At the last appointment (week 3, T2), the same plaque evaluations of T1 were repeated asking patients to brush with the other toothbrush. Entire mouth indexes were calculated and mean reductions in whole mouth plaque scores were obtained (pre-brushing minus post-brushing values) for the two tested toothbrushes. Multiple ANOVA tests (p = 0.05 ) were used 1) to compare plaque levels between male and female subjects at baseline and post-brushing, regardless the type of toothbrush, and 2) to differentiate between mean reductions in whole mouth plaque scores according to the type of toothbrush (manual versus sonic). The study population was subjected to descriptive statistical analysis; potential relationships between socio-demographic variables and obtained plaque scores were evaluated (Mann-Whitney and Kruskal-Wallis tests). RESULTS: Full-mouth plaque levels were reduced at post-brushing sessions, regardless the device, by approximately 62% (p<0.0001). Mean plaque index reductions for manual and sonic toothbrush were of 1.05 ± 0.22 and 1.19 ± 0.37, respectively. A statistically significant difference was found between the two devices (p = 0.0342). The powered sonic toothbrush removed about 10% more plaque than the manual type. From the collected questionnaire financial data, willingness to pay (WTP) values expressing economic efforts of patients for the purchase of toothbrushes were of Euros 4.83 ± 3.86 and of Euros 54.75 ± 36, for the manual and sonic devices, respectively. CONCLUSION: Within the limitations of the study, in subjects without any previous experience of a similar technology, the single use of the sonic toothbrush showed a significantly greater plaque reduction compared to the manual traditional toothbrush (null-hypothesis accepted).

A prospective longitudinal study on visuo-cognitive development in Dravet syndrome: Is there a "dorsal stream vulnerability"?

A group of five DS patients whose first development was already reported were longitudinally followed up till the scholar age. Beside the general and epileptic clinical evolution, visual and cognitive functions were investigated in order to define their trajectory and possibly provide information about mechanisms of cognitive decline as well as to improve prognosis and tertiary prevention. Neuropsychological assessment was performed with a test battery investigating the development of visual function that progressively integrates into extrastriate components and higher cognitive skills (global form and motion coherence, stereopsis, crowding cards, ABCDEFV battery, general intelligence and specific cognitive tests). Main results showed a fall in visuo-motor items including global motion coherence and specific cognitive skills, presenting a continuity of the visual function deterioration extended from basic abilities to visuo-motor dorsal pathway skills. Moreover, a case whose previous visual and cognitive functions had been in the normal range began showing a visual deterioration with increasing age, followed by the cognitive decline; that prevents from excluding in early ages a poor development in presence of a normal visual function. A dorsal stream vulnerability seems thus shown in this sample of DS patients, like in other genetic syndromes (Williams, Prader Willi. fragile-X), providing new information about mechanisms underlying cognitive decline and suggesting a possible strategy to improve their neuropsychological outcome. Larger cohorts may confirm whether these findings are part of a specific pattern of DS neuropsychological phenotype.

Surgery for posterior quadrantic cortical dysplasia. A review.

BACKGROUND: Posterior quadrant dysplastic lesions represent 3-15 % of multilobar cortical developmental pathologies, 3-5 % of all the indications to surgery for epilepsy resistant to medical treatment. OBJECTIVE AND METHODS: The objective of this study is to review the pertinent literature related to the presurgical clinical, neurophysiological, and neuroradiological evaluation of children affected by posterior quadrant dysplasia in order to discuss the intraoperative management and the different surgical techniques that have been proposed to treat this condition as well as factors related with postsurgical seizure outcome. RESULTS AND CONCLUSIONS: Seizures appear most commonly in infants and rapidly progress to a catastrophic course. They are mostly represented by focal seizures and spasms. Surface interictal video-EEG is characterized by background flattening and paroxysmal discharges prevalent on the affected side but not unusually extending to the controlateral hemisphere. The last occasionally shows an independent irritative activity in spite of the absence of further visible structural abnormalities. Most of the patients have visual field or visual attention deficits at diagnosis. Resective as well as disconnective surgical procedures have been proposed for the management of this condition, none of them having shown clear advantages in terms of seizure outcome and complications. Intraoperative electrocorticography (EcoG) and sensorimotor monitoring have been successfully used to improve the localization of the epileptic focus and reduce surgical complication rates. Undistincted lesion borders, independent controlateral ictal or/and interictal EEG activity, and incomplete resections/disconnections are among the main factors that have resulted to be associated with a worse seizure outcome.

An upgrade of the magnetic diagnostic system of the DIII-D tokamak for non-axisymmetric measurements.

The DIII-D tokamak magnetic diagnostic system [E. J. Strait, Rev. Sci. Instrum. 77, 023502 (2006)] has been upgraded to significantly expand the measurement of the plasma response to intrinsic and applied non-axisymmetric "3D" fields. The placement and design of 101 additional sensors allow resolution of toroidal mode numbers 1 ≤ n ≤ 3, and poloidal wavelengths smaller than MARS-F, IPEC, and VMEC magnetohydrodynamic model predictions. Small 3D perturbations, relative to the equilibrium field (10(-5) < δB/B0 < 10(-4)), require sub-millimeter fabrication and installation tolerances. This high precision is achieved using electrical discharge machined components, and alignment techniques employing rotary laser levels and a coordinate measurement machine. A 16-bit data acquisition system is used in conjunction with analog signal-processing to recover non-axisymmetric perturbations. Co-located radial and poloidal field measurements allow up to 14.2 cm spatial resolution of poloidal structures (plasma poloidal circumference is ~500 cm). The function of the new system is verified by comparing the rotating tearing mode structure, measured by 14 BP fluctuation sensors, with that measured by the upgraded B(R) saddle loop sensors after the mode locks to the vessel wall. The result is a nearly identical 2/1 helical eigenstructure in both cases.

Digital device in postextraction implantology: a clinical case presentation.

Aim. The aim of this work is to describe a case of immediate implant placement after extraction of the upper right first premolar, with the use of CAD/CAM technology, which allows an early digital impression of the implant site with an intraoral scanner (MHT 3D Progress, Verona, Italy). Case Report. A 46-year-old female was referred with a disorder caused by continuous debonding of the prosthetic crown on the upper right first premolar. Clinically, there were no signs, and the evaluation of the periapical radiograph showed a fracture of the root, with a mesial well-defined lesion of the hard tissue of the upper right first premolar, as the radiolucent area affected the root surface of the tooth. It was decided, in accordance with the patient, that the tooth would be extracted and the implant (Primer, Edierre implant system, Genoa, Italy) with diameter of 4.2 mm and length of 13 mm would be inserted. After the insertion of the implant, it was screwed to the scan abutment, and a scan was taken using an intraoral scanner (MHT 3D Progress, Verona, Italy). The scanned images were processed with CAD/CAM software (Exocad DentalCAD, Darmstadt, Germany) and the temporary crown was digitally drawn (Dental Knowledge, Milan, Italy) and then sent to the milling machine for production with a composite monoblock. After 4 months, when the implant was osteointegrated, it was not necessary to take another dental impression, and the definitive crown could be screwed in. Conclusion. The CAD/CAM technology is especially helpful in postextraction implant for aesthetic rehabilitation, as it is possible to immediately fix a provisional crown with an anatomic shape that allows an optimal healing process of the tissues. Moreover, the removal of healing abutments, and the use of impression copings, impression materials, and dental stone became unnecessary, enabling the reduction of the chair time, component cost, and patient's discomfort. However, it is still necessary for scientific research to continue to carry out studies on this procedure, in order to improve the accuracy, the reliability, and the reproducibility of the results.

Duchenne muscular dystrophy and epilepsy.

Cognitive and behavioral difficulties occur in approximately a third of patients with Duchenne muscular dystrophy. The aim of our study was to assess the prevalence of epilepsy in a cohort of 222 DMD patients. Epileptic seizures were found in 14 of the 222 DMD patients (6.3%). The age of onset ranged from 3 months to 16 years (mean 7.8). Seizures were more often focal epilepsy (n=6), generalized tonic-clonic seizures (n=4) or absences (n=4). They were present in 12 of the 149 boys with normal IQ (8.1%) and in two of the 73 with mental retardation (2.7%). In two cases the parents did not report any past or present history of seizures but only 'staring episodes' interpreted as a sign of 'poor attention'. In both patients EEG showed the typical pattern observed in childhood absence epilepsy. Our results suggest that the prevalence of epilepsy in our study (6.3%) is higher than in the general pediatric population (0.5-1%). The risk of epilepsy does not appear to increase in patients with mental retardation.

Pretreatment neuropsychological deficits in children with brain tumors.

Treatment of childhood brain cancer has been associated with long-term cognitive morbidity in children. In the present study, the cognitive status of children with brain tumors was examined prior to any treatment to single out the role of tumor and tumor-related factors in cognitive deficits. Eighty-three children with newly diagnosed brain tumors (mean age, 8.6 years; range, 7 months to 16.6 years; median, 9.4 years) completed an extensive battery of age-related tests to assess cognitive function before any therapeutic intervention. Magnetic resonance imaging (MRI) was used to determine tumor site and volume and tumor-related factors. Performance under test was compared with symptom duration, neurological status, epilepsy, and MRI. Cognitive difficulties are detected at diagnosis in as many as 50% of patients for some cognitive domains; 6% of patients present with true-diagnosed mental retardation. The location of the tumor is the principal determinant of cognitive deficits, with major impairment in children with cortical tumors. Symptom duration and the presence of epilepsy are significantly associated with neuropsychological disabilities, while neuroradiological tumor-related variables do not correlate clearly with neurocognitive performance. The knowledge of the pre-existing cognitive deficits is critical to evaluate the results of treatment, providing a baseline for assessing the true impact of therapy in determining cognitive decline. In addition, the study suggests that some clinical variables require careful monitoring, because they could be specifically implicated in the neuropsychological outcome; the efforts to reduce the impact of these factors could ameliorate long-term prognosis.

Epilepsy surgery of posterior quadrant dysplasia in the first year of life: experience of a single centre with long term follow-up.

Posterior quadrant dysplasia (PQD) is a rare variant of cortical dysplasia involving the posterior regions of a single hemisphere. It is always associated with early onset, refractory epilepsy often characterized by a "catastrophic" evolution. The experience on its surgical management during the first year of life is limited to sporadic, isolated cases. Between 2002 and 2005, four children less than one-year-old and affected by drug-resistant epilepsy associated with PQD were admitted to our Institution and underwent surgical treatment. One patient remained seizure-free during all the follow-up (Engel I). The remaining three children showed a recurrence of the seizures, requiring subsequent surgical procedures in two cases. In one case (Engel II), the seizure control has been obtained thanks to pharmacological treatment. The other two patients respectively had only a partial (Engel III) and a less relevant reduction of the number of seizures (Engel IV). Both the epileptic and the neuropsychological outcome of our series were significantly influenced by persistent contralateral interictal anomalies rather than by the timing of the surgical procedure. Unpredictable results should be expected in this kind of patients if there is the detection of contralateral independent epileptiform activities on the EEG at diagnosis. Parents and relatives should be aware of the results' variability, even though a reduction of seizures may be expected, enabling an easier handling of the child's condition.

Simulation of a tangential soft x-ray imaging system.

Tangentially viewing soft x-ray (SXR) cameras are capable of detecting nonaxisymmetric plasma structures in magnetically confined plasmas. They are particularly useful for studying stationary perturbations or phenomenon that occur on a timescale faster than the plasma rotation period. Tangential SXR camera diagnostics are planned for the DIII-D and NSTX tokamaks to elucidate the static edge magnetic structure during the application of 3D perturbations. To support the design of the proposed diagnostics, a synthetic diagnostic model was developed using the CHIANTI database to estimate the SXR emission. The model is shown to be in good agreement with the measurements from an existing tangential SXR camera diagnostic on NSTX.

2D soft x-ray system on DIII-D for imaging the magnetic topology in the pedestal region.

A new tangential two-dimensional soft x-ray imaging system (SXRIS) is being designed to examine the edge island structure in the lower X-point region of DIII-D. Plasma shielding and/or amplification of the calculated vacuum islands may play a role in the suppression of edge-localized modes via resonant magnetic perturbations (RMPs). The SXRIS is intended to improve the understanding of three-dimensional (3D) phenomena associated with RMPs. This system utilizes a tangential view with a pinhole imaging system and spectral filtering with beryllium foils. SXR emission is chosen to avoid line radiation and allows suitable signal at the top of a H-mode pedestal where T(e)∼1-2 keV. A synthetic diagnostic calculation based on 3D SXR emissivity estimates is used to help assess signal levels and resolution of the design. A signal-to-noise ratio of 10 at 1 cm resolution is expected for the perturbed signals, which are sufficient to resolve most of the predicted vacuum island sizes.

Protocadherin 19 mutations in girls with infantile-onset epilepsy.

OBJECTIVE: To explore the causative role of PCDH19 gene (Xq22) in female patients with epilepsy. METHODS: We studied a cohort of 117 female patients with febrile seizures (FS) and a wide spectrum of epilepsy phenotypes including focal and generalized forms with either sporadic or familial distribution. RESULTS: PCDH19 screening showed point mutations in 13 probands (11%). Mean age at seizure onset was 8.5 months; 8 patients (62%) presented with FS, 4 (33%) with cluster of focal seizures, and 1 with de novo status epilepticus (SE). Subsequent seizure types included afebrile tonic-clonic, febrile, and afebrile SE, absences, myoclonic, and focal seizures. Seven patients (54%) had a clinical diagnosis consistent with Dravet syndrome (DS); 6 (46%) had focal epilepsy. In most patients, seizures were particularly frequent at onset, manifesting in clusters and becoming less frequent with age. Mental retardation was present in 11 patients, ranging from mild (7; 64%) to moderate (1; 9%) to severe (3; 27%). Five patients (38%) had autistic features in association to mental retardation. Mutations were missense (6), truncating (2), frameshift (3), and splicing (2). Eleven were new mutations. Mutations were inherited in 3 probands (25%): 2 from apparently unaffected fathers and 1 from a mother who had had generalized epilepsy. CONCLUSIONS: PCDH19 is emerging as a major gene for infantile-onset familial or sporadic epilepsy in female patients with or without mental retardation. In our cohort, epileptic encephalopathy with DS-like features and focal epilepsy of variable severity were the associated phenotypes and were equally represented.

[Algorithm for assessment of exposure to asbestos]. / Proposta di algoritmo per la valutazione stimata dell'esposizione lavorativa ad amianto.

There is no universally approved method in the scientific literature to identify subjects exposed to asbestos and divide them in classes according to intensity of exposure. The aim of our work is to study and develope an algorithm based on the findings of occupational anamnestical information provided by a large group of workers. The algorithm allows to discriminate, in a probabilistic way, the risk of exposure by the attribution of a code for each worker (ELSA Code--work estimated exposure to asbestos). The ELSA code has been obtained through a synthesis of information that the international scientific literature identifies as the most predictive for the onset of asbestos-related abnormalities. Four dimensions are analyzed and described: 1) present and/or past occupation; 2) type of materials and equipment used in performing working activity; 3) environment where these activities are carried out; 4) period of time when activities are performed. Although it is possible to have informations in a subjective manner, the decisional procedure is objective and is based on the systematic evaluation of asbestos exposure. From the combination of the four identified dimensions it is possible to have 108 ELSA codes divided in three typological profiles of estimated risk of exposure. The application of the algorithm offers some advantages compared to other methods used for identifying individuals exposed to asbestos: 1) it can be computed both in case of present and past exposure to asbestos; 2) the classification of workers exposed to asbestos using ELSA code is more detailed than the one we have obtained with Job Exposure Matrix (JEM) because the ELSA Code takes in account other indicators of risk besides those considered in the JEM. This algorithm was developed for a project sponsored by the Italian Armed Forces and is also adaptable to other work conditions for in which it could be necessary to assess risk for asbestos exposure.

Functional hemispherectomy in children with epilepsy and CSWS due to unilateral early brain injury including thalamus: sudden recovery of CSWS.

PURPOSE: To try to prove in patients with refractory symptomatic epilepsy due to early brain injury involving thalamus and complicated by CSWS the effects of the isolation of the injured hemisphere, performed with functional hemisperectomy, on epilepsy, namely on CSWS. METHODS: Full clinical follow-up before and after surgery of two cases with CSWS onset at four years in whom functional hemispherecomy was performed with resection of inter-hemispheric connections. RESULTS: An immediate effectiveness of the surgical treatment was observed on both epileptic evolution (no more seizures) and EEG abnormalities. In particular, CSWS completely disappeared, together with a concurrent progressive improving of the cognitive and behavioural disorders. DISCUSSION: The isolation of the injured hemisphere through the section of inter-hemispheric cortico-cortical connections could prevent the contralateral diffusion of discharges coming from the injured cortex and cortico-thalamic network, favouring a normal function of thalamo-cortico-thalamic circuitries in the healthy hemisphere. That could explain the disappearance of CSWS after surgery in our patients and the consequent improvement of cognitive abilities and behaviour.

Tokamak startup using point-source dc helicity injection.

Startup of a 0.1 MA tokamak plasma is demonstrated on the ultralow aspect ratio Pegasus Toroidal Experiment using three localized, high-current density sources mounted near the outboard midplane. The injected open field current relaxes via helicity-conserving magnetic turbulence into a tokamaklike magnetic topology where the maximum sustained plasma current is determined by helicity balance and the requirements for magnetic relaxation.

Early development of epileptic infants with pre- or perinatal brain injuries: role of the epileptic disorder.

To try to understand the causative role of epilepsy PER SE in the developmental deterioration of brain injured infants, twenty-eight infants affected with early acquired, pre- and perinatal brain injuries were enrolled and divided into three groups, a) those with West syndrome, b) those with other non-West epilepsies, and c) those without epilepsy. Developmental monitoring consisted of a full clinical assessment, including examination of visual function, Griffiths developmental scales, standard EEG, long-term monitoring when necessary, and MRI, from the seizure onset or the first observation to the end of follow-up. Patients with epilepsy showed at study onset abnormal clinical features (neurological and developmental) distinct from those of non-epileptic patients, partially due to the varying severity of their brain injuries. A definite differentiation between groups was observed in the clinical evolution that showed among the epileptic patients, mostly in West syndrome, a significant deterioration. Moreover, impaired visual function at seizure onset was possibly associated with a bad developmental evolution. A developmental deterioration, mostly in West syndrome, accounts for a causative role of the epileptic disorder PER SE, but in few cases it was also observed in infants with only a brain injury, suggesting other aetiopathogenic mechanisms. The predictive value of early visual function seems to be confirmed.

Early hemispherectomy in catastrophic epilepsy: a neuro-cognitive and epileptic long-term follow-up.

The authors report their experience about a neuro-cognitive and epileptic long-term follow-up of children with catastrophic epilepsy treated with hemispherectomy in the first 5 years of life. Nineteen children with resistant epilepsy that significantly interfered with their neuro-cognitive development underwent hemispherectomy within 5 years of life (mean: 2 years, 3 months; range: 5 months to 5 years). All patients were assessed before surgery and after, at least at the end of the follow-up (mean: 6 years and 6 months; range: 2-11 years and 2 months) with a full clinical examination including motor ability and functional status evaluation as well as behaviour observation, neuroimaging and an ictal/interictal prolonged scalp video-EEG. A seizure-free outcome was obtained in 73.7% of patients. Gross motility generally improved and cognitive competence did not worsen, with an evident progress in two cases. Consistently with previous reports, evolution was worse in cortical dysplasia than in progressive or acquired vascular cerebropathies. The excellent epileptic outcome and the lack of developmental deterioration in comparison with other more aged series seem to suggest a possible better evolution in earlier surgery treatment. To confirm this suggestion, however, further experience with larger series is needed.

Seizure semiology of lesional frontal lobe epilepsies in children.

The aim of the study was to analyse the semiology of seizures in children with frontal lobe epilepsy (FLE) and to compare them with other paediatric cohorts described in the literature as well as with adult counterparts. We analysed 174 registered seizures of 18 cases under 12 years with lesional epilepsy whose frontal origin was defined by the concordance of neuroimaging and ictal electrographic findings, and confirmed by surgery in the six cases operated on. Seizures were generally short, with a high daily frequency and usually related to sleep. The most characteristic semiological pattern consisted of complex motor seizures, particularly hypermotor. Often seizures corresponded to a mixture of different semiological patterns (tonic, gelastic, automotor, hypermotor, versive) presenting in the same seizure, often as a unique type in the same patient. With regard to several aspects the semiology of FLE in our cohort looks like that reported in adult series, in particular as to the frequency of complex motor seizures. However, our cohort was also characterised by a more protean array of seizure semiology, stressing the occurrence of seizures typically present in adults (versive and complex motor) and of some seizure patterns more characteristic in children such as epileptic spasms; moreover, the rare occurrence of secondarily generalised tonic clonic seizures (SGTCS) was confirmed.