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Network approaches can be used to study sociosexual partnerships and identify individuals at high risk of infection. Little is known about the cost structure of these services and their association with STD diagnoses.We collected costs associated with using a peer network strategy to recruit men who have sex with men and transwomen of color in 4 counties in North Carolina: Guilford, Forsyth, Durham, and Wake from February through October 2019. We used a comprehensive costing approach to gather detailed retrospective information on the intervention cost, broken down by category and programmatic activity.The sociosexual networks collected consisted of 31 initial seeds (index cases) and 49 peers of those seeds. In peers, 5 cases of human immunodeficiency virus (HIV) and 10 cases of syphilis were identified. The cost per case (HIV or syphilis) identified was $7325. Personnel costs accounted for 80% of total expenditures, followed by laboratory expenses (12%). Personnel cost was distributed between disease intervention specialist patient navigators (51%), nonclinical (37%), and management (12%) staff. General administration was the costliest programmatic activity (37%), followed by case management and field services (37%), and study activities (11%). The estimated average cost per patient tested was $2242.Finding positive peer cases in nonclinical settings is costly but may be crucial for limiting the spread of sexually transmitted diseases. The cost of staff was the major driver. This study demonstrates that using a network strategy can be a cost-effective way to identify, test, and refer patients at high risk of syphilis and HIV infections to care.

This paper presents the design and testing of a scale proof-of-concept prototype robotic end-effector system for autonomous robotic shotcrete application and radiation surveying in underground uranium mining environments. The system presented consists of two functionally distinct prototype tools that achieve the independent tasks of autonomous robotic spray pattern control and surface radiation surveying. The first prototype tool presented is a novel, robotic shotcrete spraying tool that is capable of autonomously maintaining and adjusting its circular spray pattern diameter on target surfaces in response to changes in target surface distance. Control algorithms are presented that give the robotic shotcrete spraying tool the capability to produce advanced figure eight and spiral spraying patterns for surface preparation applications that involve spot filling deep surface cracks and pockets. Physical testing of the prototype tool empirically verified its ability to maintain circular spray pattern diameters at various target distances and demonstrated the application potential of the advanced figure eight and spiral spraying patterns. The second prototype tool presented is a Geiger–Müller tube-based radiation detection tool that uses lead shielding and a single-hole collimator in combination with precise robotic positioning to capture localized radiation measurements of surfaces within radiation-rich environments. Physical testing of the prototype tool demonstrated its ability to create radiation survey profiles that distinctly characterized the radiological profile of test target surfaces embedded with various radioactive sources.

The present study investigates stall-induced vibrations on a IEA-15-RWT wind turbine blade. At standstill and under specific strong crosswind conditions, simulations using the codes OpenFAST and DeepLines WindTM exhibit large-amplitude vibrations. Results of both codes are first compared, showing an overall good agreement. Then, the influence of the wind misalignment angle is assessed as well as the choice of aerodynamic polar datasets. Vibrations are observed within two well-marked angular sectors, and the high sensitivity of the phenomenon to the choice of polars is highlighted. Finally, a simplified model based on a spring-mounted aeroelastic section is used to help identifying which type of unstable aeroelastic modes may be at play.

Background: Obstetrical analgesia remains a matter of controversy because of the fear of neurotoxicity of local anesthetics on demyelinated fibers or their potential relationship with subsequent relapses. Objective: To assess the impact of neuraxial analgesia on the risk of relapse during the first 3 months post-partum, with a focus on women who experienced relapses during pregnancy. Methods: We analyzed data of women followed-up prospectively during their pregnancies and at least 3 months post-partum, collected in the Pregnancy in Multiple Sclerosis (PRIMS) and Prevention of Post-Partum Relapses with Progestin and Estradiol in Multiple Sclerosis (POPARTMUS) studies between 1992–1995 and 2005–2012, respectively. The association of neuraxial analgesia with the occurrence of a post-partum relapse was estimated by logistic regression analysis. Results: A total of 389 women were included, 215 from PRIMS and 174 from POPARTMUS. In total, 156 women (40%) had neuraxial analgesia. Overall, 24% experienced a relapse during pregnancy and 25% in the 3 months post-partum. Women with a pregnancy relapse were more likely to have a post-partum relapse (odds ratio (OR) = 1.83, p = 0.02), independently of the use of neuraxial analgesia. There was no association between neuraxial analgesia and post-partum relapse (OR = 1.08, p = 0.78). Conclusion: Neuraxial analgesia was not associated with an increased risk of post-partum relapses, whatever multiple sclerosis (MS) activity during pregnancy.

Summary The coupling of the fluid-flow simulator PumaFlow™ and the geomechanical simulator Abaqus™ is implemented with the help of SIMULIA Co-Simulation Services™. It allows to take into account, in the fluid-flow simulator, the variations of porosities and permeabilities with respect to volumetric strain and geomechanical porosity related to stress changes. The method is validated using an analytical solution for a problem of consolidation of a soil layer. Then, the thermal production of a homogeneous heavy-oil reservoir is computed using the co-simulation of the fluid-flow and the geomechanical simulators. This coupling appears more user-friendly and its computing more efficient than the coupling performed a few years ago using shell scripts.

This retrospective study evaluated the effectiveness of salivary gland radiotherapy for reducing sialorrhea in patients with amyotrophic lateral sclerosis (ALS).From August 2001 to February 2008, 21 patients with amyotrophic lateral sclerosis (six men, 15 women; mean age 61.2 years, range 39-81) received external beam radiotherapy for sialorrhea (evaluation by the ALS Functional Rating Scale). All patients had previously received pharmacological treatments with unsatisfactory results or side effects. The mean dose was 19.1Gy (range 3-48), delivered in five fractions (range 1-16) on 17 days (range 1-77). Eight patients received 3D-conformal and 13 received 2D-conformal radiotherapy. Clinical target volumes included the parotids and submandibular glands (18 patients), submandibular glands and one parotid (one patient), or parotids (two patients). Thirteen patients were treated with 5.5-6MV photons and eight were treated with 6-15MeV electrons. A satisfactory salivary response was defined as complete or partial improvement. The median follow up was 10.4 months (range 0.4-26). One patient was lost to follow up.A positive response was observed in 65% of patients during a mean of 7 months (range 1-23). Four patients (20%) treated with photons and no patients treated with electrons experienced acute toxicity. Half (50%) the patients treated with photons and 87.5% of patients treated with electrons responded positively (P=0.09). Positive responses were more common with a high total dose (≥16Gy; 78.6%) than a low total dose (16Gy; 33%; P=0.07). No differences were observed in tolerance (P=0.27). Age and sex did not impact the response.Salivary gland radiotherapy effectively reduced sialorrhea in patients with amyotrophic lateral sclerosis. An adequate compromise between toxicity and efficiency was achieved with 3D-conformal radiotherapy delivered with electrons to parotids and submandibular glands in a total dose of 16Gy or more (mean: 20Gy in five fractions).

Background and purpose: Deletion of TREK-1, a two-pore domain K+ channel (K2P) activated by volatile anaesthetics, reduces volatile anaesthetic potency in mice, consistent with a role for TREK-1 as an anaesthetic target. We used TREK-1 knockout mice to examine the presynaptic function of TREK-1 in transmitter release and its role in the selective inhibition of glutamate vs GABA release by volatile anaesthetics. Experimental approach: The effects of halothane on 4-aminopyridine-evoked and basal [3H]glutamate and [14C]GABA release from cerebrocortical nerve terminals isolated from TREK-1 knockout (KO) and littermate wild-type (WT) mice were compared. TREK-1 was quantified by immunoblotting of nerve terminal preparations. Key results: Deletion of TREK-1 significantly reduced the potency of halothane inhibition of 4-aminopyridine-evoked release of both glutamate and GABA without affecting control evoked release or the selective inhibition of glutamate vs GABA release. TREK-1 deletion also reduced halothane inhibition of basal glutamate release, but did not affect basal GABA release. Conclusions and implications: The reduced sensitivity of glutamate and GABA release to inhibition by halothane in TREK-1 KO nerve terminals correlates with the reduced anaesthetic potency of halothane in TREK-1 KO mice observed in vivo. A presynaptic role for TREK-1 was supported by the enrichment of TREK-1 in isolated nerve terminals determined by immunoblotting. This study represents the first evidence for a link between an anaesthetic-sensitive 2-pore domain K+ channel and presynaptic function, and provides further support for presynaptic mechanisms in determining volatile anaesthetic action. British Journal of Pharmacology (2007) 152, 939–945; doi:10.1038/sj.bjp.0707450; published online 10 September 2007

Lyme disease is the most common tick borne disease and is caused by Borrelia burgdorferi sensu lato. Ticks of the genus Ixodes are the vectors that transmit the infection to host mammals in endemic foci. Ixodes is infected by Borrelia at larval stage when it feeds on infected mammals. Man is an occasional host. The infection risk is linked to interaction between human and the natural environment. Strategies for prevention are closely related to the enzootic cycle of the Ixodes tick. Environmental measures to reduced tick density or host mammals are expensive, need to be repeated annually and cannot be applied to large areas. The primary prevention could be reduced to personal preventive measures such as reducing the amount of exposed skin and frequent checking for ticks. The risk of Lyme disease transmission after a tick bite is relatively low, and remains under 4%. The transmission rate depends on the duration of feeding. A rapide tick removal with fine tweezers or preferably special forceps and disinfection of the bite site appear to be the best technique. The absence of scientific evidence, and the risk of adverse events does not lead to recommending antimicrobial prophylaxis. Follow-up and educating the patients on the disease, clinical manifestation, and later primary prevention should be undertaken.

Resume La prise en charge symptomatique des patients atteints de sclerose laterale amyotrophique (SLA) est essentielle. Effectuee au mieux dans une approche multidisciplinaire, elle suit une evaluation systematique des signes generaux, domines par les troubles anxieux ou de l’humeur, la fatigue, les difficultes du transit, les douleurs, les troubles du sommeil. Les plaintes directement liees a l’atteinte du premier motoneurone, spasticite et labilite emotionnelle en rapport avec un syndrome pseudo-bulbaire ou du second motoneurone, crampes, fasciculations ou hypersalivation justifient aussi des approches specifiques.

In the thalamus, noradrenergic output from the pontine nucleus locus coeruleus (LC) may actively shape the response properties of various sensory networks en route to the cortex. Little is known, however, about the involvement of ascending noradrenergic innervation of the somatosensory thalamus in the processing of nociceptive information. To address this question, we combined the study of Fos expression upon nociceptive tooth pulp stimulation in the anaesthetized rat, with the detection of retrogradely traced neurones from the somatosensory thalamus. Cell bodies labelled retrogradely from the left thalamus were observed on both sides of the LC, with an ipsilateral predominance (n = 8). Electrical stimulation of the right incisor pulp (n = 4) provoked a significantly stronger Fos expression (around twice) than sham surgery (n = 4), in both the ipsi- and contralateral LC. Significantly larger numbers of double labelled neurones were counted in the LC of tooth-pulp-stimulated animals (representing around 30% of retrogradely labelled cells in LC) than in the LC of sham animals. They were found bilaterally, but with a clear, significant, ipsilateral (i.e. left) predominance. The present data offer an anatomical framework to understand how the LC is involved in the sensory processing of nociceptive information in the thalamus. For the first time, it is shown that nociceptive stimulation activates LC neurones projecting to the somatosensory thalamus. This suggests a new role for LC in modulating nociception within the thalamus.

Algorithms for low-pass and high-pass three-pole recursive Butterworth filters of a given cut-off frequency have been developed. A band-pass filter can be implemented by sequential application of algorithms for low- and high-pass filters. The algorithms correspond to infinite impulse-response filters that have been designed by applying the bilinear transformation to the transfer functions of the corresponding analog filters, resulting in a recursive digital filter with seven real coefficients. Expressions for filter coefficients as a function of the cut-off frequency and the sampling period are derived. Filter performance is evaluated and discussed. As in the case of their analog counterparts, their transfer function shows marked flattening over the pass band and gradually higher attenuation can be seen at frequencies above or below the cut-off frequency, with a slope of around 60 dB/decade. There is a 3 dB attenuation at the cut-off frequency and a gradual increase in phase shift over one decade above or below the cut-off frequency. Low-pass filters show a maximum overshoot of 8% and high-pass filters show a maximum downwards overshoot of approximately 35%. The filter is mildly under-damped, with a damping factor of 0.5. On an IBM 300GL personal computer at 600 MH with 128 MB RAM, filtering time with MATLAB 5.2 running under Windows 98 is of the order of 50 ms for 60000 samples. This will be adequate for on-line electroencephalography (EEG) applications. The simplicity of the algorithm to calculate filter coefficients for an arbitrary cut-off frequency can be useful to modern EEG laboratories and software designers for electrophysiological applications.

EEG/VEP and fMRI responses to periodic visual stimulation are reported. The purpose of these experiments was to look for similar patterns in the time series produced by each method to help understand the relationship between the two. The stimulation protocol was the same for both sets of experiments and consisted of five complete cycles of checkerboard pattern reversal at 1.87 Hz for 30 s followed by 30 s of a stationary checkerboard. The fMRI data was analyzed using standard methods, while the EEG was analyzed with a new measurement of activation-the VEPEG. Both VEPEG and fMRI time series contain the fundamental frequency of the stimulus and quasi harmonic components-an unexplained double frequency commonly found in fMRI data. These results have prompted a reappraisal of the methods for analyzing fMRI data and have suggested a connection between our findings and much older published invasive electrophysiological measurements of blood flow and the partial pressures of oxygen and carbon dioxide. Overall our new analysis suggests that fMRI signals are strongly dependant on hydraulic blood flow effects. We distinguish three categories of fMRI signal corresponding to: focal activated regions of brain tissue; diffuse nonspecific regions of steal; and major cerebral vessels of arterial supply or venous drainage. Each category of signal has its own finger print in frequency, amplitude, and phase. Finally, we put forward the hypothesis that modulations in blood flow are not only the consequence but are also the cause of modulations in functional activity.

The aim of this study was to evaluate the effect of long-term clozapine treatment on body weight changes in neuroleptic-resistant chronic schizophrenic patients and to compare it with that of classical antipsychotic agents. The body mass index (BMI) of 96 neuroleptic-resistant chronic schizophrenic patients was calculated before the beginning and after long-term (mean +/- SD 1.7 +/- 1.3 years) clozapine treatment. These data were compared to the BMI of 98 chronic schizophrenic patients maintained on classical antipsychotic agents for a similar duration (mean +/- SD 1.9 +/- 1.6 years). A significant elevation in BMI was detected in both groups during these periods (P0.0001 versus baseline, for both groups). The change in BMI (delta BMI) was similar in both groups (P0.9). We conclude that the increase in body weight caused by long-term (6 months) clozapine treatment is comparable to that obtained following long-term classical antipsychotic agents treatment.

OBJECTIVES—To study the variability, topography, polarity, duration, and incidence of interictal epileptiform discharges (EDs) in the scalp EEG and electrocorticogram (ECoG) from 16 patients with temporal lobe epilepsy who underwent surgical treatment. METHODS—Preoperative scalp EEGs during quinalbarbitone induced sleep were compared with preresection ECoGs obtained under general anaesthesia. The analysis was based on the initial ECoG record obtained before activation by intravenous thiopentone, and the EEG during stages I and II of sleep. RESULTS—On the scalp, 15 patients had a single discharge pattern, spikes were predominantly negative, EDs were of largest amplitude at the anterior temporal electrode in 13 patients and mean discharge incidence was 4.0 (SD 4.2) discharges/min. In ECoG recordings, nine patients had two independent ECoG patterns, the polarity of spikes was negative, positive-negative, or positive, the site of maximal amplitude varied greatly between subjects, discharge incidence was 7.3 (SD 3.9) discharges/min. There was no relation between the topography of the largest spikes on the scalp and in the ECoG. In 14 patients, scalp spikes showed statistically significant longer duration on the scalp than in the ECoG. In seven patients who had frequent widespread ECoG discharges, averaging spikes across ECoG channels generated spiky patterns of duration similar to that of scalp spikes. CONCLUSION—It seems that, in temporal lobe epilepsy, scalp discharges originate from widespread ECoG discharges and tend to produce a stereotyped pattern on the scalp with largest amplitudes at the anterior temporal electrodes. This is probably due to local anatomical peculiarities in the brain coverings, such as skull discontinuities, rather than to the location of neuronal generators within the temporal lobe. Due to spatiotemporal averaging, widespread cortical discharges which become asynchronous during propagation appear with increased duration and blunted waveform in the EEG, whereas sharply localised phenomena such as positive focal spikes are not recorded from the scalp.

Medical imaging has, in the past 25 years, been revolutionized by the introduction and subsequent widespread clinical use of X-ray computerized tomography (CT). CT led the way for the introduction of several new tomographic methods that use physical techniques as diverse as positron annihilation and nuclear magnetic resonance to obtain high spatial resolution reconstructed images of both human anatomy and, more recently, human biological function. The central theme running throughout this revolution is the tomographic principle. This article describes the key elements in present-day medical imaging using tomography as the unifying concept. X-ray CT, positron emission tomography (PET) and magnetic resonance imaging (MRI) are described as far as possible in non-mathematical terms. Most space is devoted to MRI, the newest of the methods and the one which probably holds most promise for the future in terms of its range of application.

In a previous study we showed that fast moving stimuli activate V5, an area specialized for motion, at very short latencies through a pathway that reaches it without passing through VI. Using the same technique of visual evoked responses, we have tested our conclusions by studying patient GY, whose VI is damaged but whose V5 is intact. In spite of the contralateral hemi-blindness due to his V1 lesion, GY has a residual visual capacity that allows him to perceive, consciously, fast but not slow moving stimuli presented in his affected hemifield. By stimulating GY's 'blind' hemifield and comparing the responses with those obtained from normal subjects, we were able to study the relative contribution of VI and V5 to the visual evoked response to motion in normal subjects. We found that GY's early response to fast motion is preserved and correlates with activity elicited in control subjects over area V5, while slow motion, pattern offset, and pattern reversal stimuli failed to elicit responses in GY. The results confirm our previous conclusions : namely, that the early part of the motion evoked response is generated in area V5 and that signals reach this area through a dynamically parallel pathway that bypasses area V1. They go on to demonstrate that neurophysiological activity in the prestriate cortex correlates with the conscious visual perception of motion.

The genetic photosensitive epilepsy of the Fayoumi chicken was transferred to normal chickens by in situ grafts at 2 days of incubation, of both the prosencephalic and mesencephalic brain vesicles taken from epileptic embryos. However, mesencephalic graft is sufficient to allow convulsions under sound stimulation. Typical EEG patterns are recorded in chimeras having the prosencephalon plus or not the mesencephalon. We conclude that, in this mutant, the whole neural tissue is affected, but the seizure generator is localized inside the mesencephalon, and specific sensory pathways are necessary for seizures to occur.

We report the case of a 70-year-old man who developed probable unilateral Creutzfeldt-Jakob disease. Clinically, he presented with right hemiparesis, progressive aphasia, temporospatial disorientation and cerebellar ataxia and later on, myoclonia. The MRI showed a hypersignal from the left caudate in DWI with decreased ADC. Repeated electroencephalograms showed a slow background rhythm in the left hemisphere with superimposed periodic, biphasic and triphasic sharp-wave complexes in the left temporal region. Death occurred after 5weeks. Although exceptional, unilateral Creutzfeldt-Jakob disease was retained as possible.

The hypothesis that focal scalp EEG and MEG interictal epileptiform activity can be modelled by single dipoles or by a limited number of dipoles was examined. The time course and spatial distribution of interictal activity recorded simultaneously by surface electrodes and by electrodes next to mesial temporal structures in 12 patients being assessed for epilepsy surgery have been studied to estimate the degree of confinement of neural activity present during interictal paroxysms, and the degree to which volume conduction and neural propagation take part in the diffusion of interictal activity. Also, intrapatient topographical correlations of ictal onset zone and deep interictal activity have been studied. Correlations between the amplitudes of deep and surface recordings, together with previous reports on the amplitude of scalp signals produced by artificially implanted dipoles suggest that the ratio of deep to surface activity recorded during interictal epileptiform activity on the scalp is around 1:2000. This implies that most such activity recorded on the scalp does not arise from volume conduction from deep structures but is generated in the underlying neocortex. Also, time delays of up to 220 ms recorded between interictal paroxysms at different recording sites show that interictal epileptiform activity can propagate neuronally within several milliseconds to relatively remote cortex. Large areas of archicortex and neocortex can then be simultaneously or sequentially active via three possible mechanisms: (1) by fast association fibres directly, (2) by fast association fibres that trigger local phenomena which in turn give rise to sharp/slow waves or spikes, and (3) propagation along the neocortex. The low ratio of deep-to-surface signal on the scalp and the simultaneous activation of large neocortical areas can yield spurious equivalent dipoles localised in deeper structures. Frequent interictal spike activities can also take place independently in areas other than the ictal onset zone and their interictal propagation to the surface is independent of their capacity to trigger seizures. It is concluded that: (1) the deep-to-surface ratios of electromagnetic fields from deep sources are extremely low on the scalp; (2) single dipoles or a limited number of dipoles are not adequate for surgical assessment; (3) the correct localisation of the onset of interictal activity does not necessarily imply the onset of seizures in the region or in the same hemisphere. It is suggested that, until volume conduction and neurophysiological propagation can be distinguished, semiempirical correlations between symptomatology, surgical outcome, and detailed presurgical modeling of the neocortical projection patterns by combined MEG, EEG, and MRI could be more fruitful than source localization with unrealistic source models.

This paper, written by French amyotrophic lateral sclerosis (ALS) center experts, presents an update of recent advances in fundamental, epidemiological and clinical research in ALS based on a review of the literature between September 2008 and November 2009. Among other pathophysiological mechanisms, the role of stress of the endoplasmic reticulum and the importance of energetic metabolic disturbances have been underscored. In the field of genetics, research has been advanced through the identification of mutations of the gene FUsed in Sarcoma/Translated in LipoSarcoma (FUS/TLS) in individuals with familial and sporadic ALS. This gene is involved in the regulation of transcription, splicing and RNA transport, and has functional homology to another ALS gene, TARDBP, which suggests that a common mechanism may underlie motor neuron degeneration. A report showed that mice expressing a mutant form of human TDP-43 develop a progressive and fatal neurodegenerative disease reminiscent of both ALS and frontotemporal lobar degeneration with ubiquitin aggregates (FTLD-U), providing a new animal model that may help to better understand the pathophysiology and test new therapeutics. Beside genetic studies, several epidemiologic studies have investigated the role of environmental factors. A recent study suggests that smoking is a risk factor for developing ALS and it is hypothesized that this could occur through lipid peroxidation via formaldehyde exposure. From a neuroprotective perspective, trials with IGF-1, sodium valproate, coenzyme Q or glatiramer acetate have failed to demonstrate any beneficial effect. A study published in 2008 argued that lithium may have a neuroprotective effect in ALS mice and also in patients. However, two preclinical studies failed to replicate the neuroprotective effect of lithium in ALS mice. Therapeutic trials have been performed or are currently ongoing in Europe and North America. Their results have not yet been published.

Specific heat and magnetization measurements have been made in the temperature range 1.7–5.2 K on ternary spin-glass alloys based on Cu–0.25 at.% Mn and Cu-4 at.% Mn. Changes in both the thermal and the magnetic properties with the concentration of a third element (Pt or Al) provide evidence for the importance of the distribution of interaction strengths in determining the details of spin-glass phenomena. A simple scaling hypothesis applied to the thermal data suggests that, whereas the addition of Al to Cu-Mn preserves the binary alloy interaction distribution, the addition of Pt introduces new terms that may be attributable to the Dzyaloshinsky-Moriya interaction.

An ASSEMBLER routine is described for data acquisition and "on-line" averaging, artefact rejection and graphic display of data on a personal microcomputer (IBM compatible). The user determines the number of input channels, sampling frequency, number of samples, input range, stimulation frequency (epoch frequency) and the number of epochs to be acquired and averaged. Data from each epoch are scanned in search of saturating artefacts and will be added to previous epochs if none is found. Data are then graphically displayed as voltage versus time before acquiring next epoch. Display options can be defined by the user at run time by means of the keyboard and include: display of last epoch, display of the average, storage screen and refreshing screen after every epoch. High data transfer rates and program speed allows for high stimulation rates in the presence of on line graphic display. The computer then behaves as a multichannel digital oscilloscope with access to large memory buffers, disk storage, high averaging capabilities, artefact rejection and wide potential for data analysis. Its applications to the recording of magnetic and electric evoked responses are illustrated. The program is available from the authors.