bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluorescence Quenching of a Benzimidazolium–based Probe for Selective Detection of Picric Acid in Aqueous Medium
Authors: Joshi Sunita , Kumari Santosh , Chamorro Eduardo , Pant Debi D. , Sakhuja Rajeev
Published: June 2016

A fluorescent coumaryl linked benzimidazolium salt has been synthesized, characterized and found to be highly selective for nanomolar detection of commonly used explosive picric acid, over other aromatic explosives in aqueous medium. The quenching constant and detection limit of the sensor for picric acid was found to be KSV=1.58 × 104 M−1 and 208 nM respectively. The high sensitivity of the sensor toward picric acid can be predominantly attributed to the ground‐state charge‐transfer complex formation based on UV‐visible studies, time resolved fluorescence results and Density Functional Theory (DFT) calculations.
Early elementary students’ understanding of complex ecosystems: A learning progression approach
Authors: Hokayem Hayat , Gotwals Amelia Wenk
Published: June 2016

Engaging in systemic reasoning about ecological issues is critical for early elementary students to develop future understanding of critical environmental issues such as global warming and loss of biodiversity. However, ecological issues are rarely taught in ways to highlight systemic reasoning in elementary schools. In this study, we conducted semi‐structured interviews with 44 students from the first through fourth grades. Using an iterative process, we developed an empirically grounded learning progression that captures how elementary students use systemic reasoning to explain interactions in ecosystems. This learning progression contains five reasoning patterns: anthropomorphic reasoning, concrete practical reasoning, simple causal reasoning, semi‐complex causal reasoning, and complex causal reasoning. The results also show that many students exhibited mixed‐level reasoning, meaning that they used reasoning patterns at multiple levels to construct a single response. We discuss the implications of the study for learning progression research and teaching ecosystems at early elementary grades. © 2016 Wiley Periodicals, Inc. J Res Sci Teach 53: 1524–1545, 2016
Basic characteristics of self‐control corona discharge air ionizer
Authors: Sato Takashi , Ikehata Takashi , Terashige Takashi , Okano Kazuo
Published: June 2016

We propose a self‐controlling corona discharge air ionizer for the static neutralization of electronic products in manufacturing processes. This air ionizer automatically generates only the quantity of ions required to neutralize a charged product, without the need for a control system. This is possible as the device generates ions based on the combination of the electric field of the ionizer emitter, to which a threshold voltage is applied, and the electric field of the product. In this study, the required threshold voltage values were determined by assessing the relationship between the neutralization current and the emitter voltage. The neutralization speed and the final product voltage after neutralization obtained from the ionizer operating on AC voltage were investigated using a charged‐plate monitor. The time span required to reduce the charge on a metal plate with a capacitance of 20 pF from 1000 to 100 V was found to be less than 1.0 s, indicating that this device has practical applications. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Fuzzy logic‐based concept for high‐voltage substation risk management against lightning
Authors: Grujić Aleksandra , Stojković Zlatan
Published: June 2016

This paper presents the methodology, algorithms, and application of the expanded version of the software tool formed by means of the powerful AutoCAD software and the programming language Visual Basic, enabling both the estimation and visualization of the 3D lightning protection (LP) zone for a high‐voltage substation (HVS) and risk management against lightning. Although HVS is outside the scope of IEC 62305‐2, its methodology is adapted in this paper to the case of HVS. The approximate reasoning algorithm for risk management against lightning is based on the implementation of fuzzy sets that describe the measure of the HVS LP and the corresponding risk. Sensitivity analysis pertaining to the risk from the lightning flash (LF) and the corresponding economic evaluation have been carried out for the actual 220 and 110 kV HVSs in function of the impulse current magnitude and protective measure implementation. The formed software tool application enables the formation of the map of risk in the function of the considered facility and the impulse current of the LF, which will represent the constituent part of the future information system of electric power transmission and distribution organizations intended for risk management. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
A comparative study for current transformer dimensioning in overcurrent relay
Authors: Abu Bakar A. H. , Zali S. M. , Tan Chia Kwang , Illias H. A. , Mokhlis H.
Published: June 2016

Dimensioning a current transformer (CT) is one of the most important tasks during the substation planning process. The installation of a correctly specified CT will ensure the integrity of the protection scheme. However, some parameters required for dimensioning a CT can be obtained only after the CT is installed in the substation. Because of the conflicting requirements, utility companies commonly adopt a simplified approach in compensating for the missing parameters. Two other methods for dimensioning CT under the given constraint during the planning stage have also been proposed by several authors. In view of the availability of the three methods of approximating CT specifications, this paper will conduct a comparative study to evaluate their accuracies. The approximated specifications of the CT during the planning stage are compared against those measured from a practical substation. Based on the findings from the comparative studies, the most reliable approach for CT dimensioning during the planning stage is proposed. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Islanding detection using wavelet transform and rate of change of frequency relay method in presence of different distributed generation technologies
Authors: Hovanessian Arin , Norouzi Mohammad‐Ali
Published: June 2016

In this paper, islanding detection in the presence of different technologies of distributed generations (DGs) is discussed. Three types of DGs, namely a synchronous generator (SG), a wind energy conversion system (WECS), and a photovoltaic (PV) system, with distribution network parameters as well as linear and nonlinear loads are simulated using the Power System Computer Aided Design/Electromagnetic Transients Including DC (PSCAD/EMTDC) software. To detect the island state, a comprehensive islanding detection algorithm based on wavelet transform (WT) and rate of change of frequency (ROCOF) relay method is considered. To determine the islanding threshold value, the voltage and frequency values of sensitive buses are sampled at regular intervals, and the signals are analyzed with WT using MATLAB. The proposed algorithm could detect the exact island state definitively with the consideration of various disturbance signals such as capacitor bank switching, induction motor switching, and the sudden disconnection of power sources and loads from different buses of the distribution network. The results of the simulation are validated with the logic of ROCOF relay islanding detection method, which determines the accuracy threshold value when the power generation and load consumption difference is negligible. In addition, the proposed algorithm based on the rested DG's output power in the islanding state can supply prioritized loads based on thier importance. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Test circuit of impulse spark‐over voltage with different rates of rise for gas discharge tubes
Authors: Zhou Mi , Wang Jianguo , Cai Li , Li Xianqiang , Fan Yadong , Xue Jian
Published: June 2016

The impulse spark‐over voltage of the gas discharge tube (GDT) is strongly related to the rate of rise (RoR) of the voltage. At present, due to the convenience of the test instrument, conventional impulse waveforms, such as 1.2/50 and 10/700 μs, are often adopted to conduct such kind of test for GDT. It has been found that these waveforms are able to generate valid waveforms only with limited RoRs and relatively narrow valid voltage ranges. This paper deals with a simple series RC circuit to test the GDT's impulse spark‐over voltage using a ramp voltage, which is approached by an initial portion of a steeply rising voltage impulse whose normal peak value is several times the breakdown voltage of the GDT. The basic circuit theory is described, and the RoR of the output voltage is correlated with the circuit parameters. Moreover, the series RC circuit in this paper is found to be able to deliver a ramp voltage with more consistent RoR than an RLC circuit. The results in this paper provide some suggestions for the revision of relevant standards (e.g., ITU‐T K.12 and IEC 61643‐311). Circuit parameters for different RoRs ranging from 100 V/μs to 1 kV/ns are also established. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Neutralizing interferences in two‐hop amplify‐and‐forward MIMO relay systems
Authors: Shin Changyong , Noh Gosan
Published: June 2016

In this paper, we present the interference neutralization technique for two‐hop multiple‐input multiple‐output (MIMO) relay systems. It enables multiple MIMO transmitters (sources) to simultaneously transmit independent data streams to their MIMO receivers (destinations) without mutual interferences, thereby improving spectral efficiency of the systems. To neutralize the mutual interferences using multiple amplify‐and‐forward (AF) MIMO relays, we establish the sufficient condition for the antenna configuration in the MIMO relay networks, and provide a filter design technique for the AF MIMO relays. The proposed method increases sum rates of the systems linearly with the number of transmitters participating in simultaneous transmission. To improve the sum rates further, this method is combined with transmit power allocation using the water‐filling algorithm. In addition, it is shown that by employing the minimum number of relays required to meet the sufficient condition, the system cost for the proposed method can be reduced without compromising the sum rate performance severely. Finally, simulation results successfully demonstrate that by exploiting radio resources such as frequency and time efficiently, the proposed method achieves a higher sum rate than the existing techniques based on interference avoidance. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
System throughput improvement by optimizing timeout for wireless network coding and frame aggregation on CSMA/CA bidirectional two‐hop relaying prototype
Authors: Maruta Kazuki , Mashino Jun , Otsuki Nobuaki , Sugiyama Takatoshi
Published: June 2016

This paper reports an outdoor experiment to optimize the timeout of wireless network coding (WNC) and frame aggregation (FA), which are implemented to carrier sense multiple access with collision avoidance (CSMA/CA)‐based wireless two‐hop relay prototype. The system throughput is improved. In the prototype, FA is implemented at the terminal nodes. Timeout function for WNC is available at the relay node and that for FA is available at the terminal nodes. Our outdoor experiment shows that optimizing the timeout values of WNC and FA can improve system throughput by 2.04‐fold compared to the conventional relay without WNC or FA. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Fruit juice–alcohol mixture analysis using machine learning and electronic nose
Authors: Ordukaya Emre , Karlik Bekir
Published: June 2016

The aim of this study is to analyze the raw data collected from a fruit juice–alcohol mixture (a fruit juice–alcohol mixture and a fruit juice–multiple alcohol mixture) and the Halal authentication of a fruit juice–alcohol mixture with electronic nose. Machine learning techniques such as naïve Bayesian classifier, K‐nearest neighbors (K‐NN), linear discriminant analysis (LDA), decision tree, artificial neural network (ANN), and support vector machine (SVM) were used to classify the feature of these collected raw data. There are three types of classification: the first one is a fruit juice and an alcohol mixture type; the second is a fruit juice and multiple alcohol mixture types, and the third is a Halal authentication of a fruit juice and alcohol mixture. We aimed at making cocktails with more successful results on the first two types of classification in the work. Also, we focused on Halal authentication of fruit juice–alcohol mixture in the third classification. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Model predictive control for tendon‐driven balloon actuator on simulation
Authors: Nagase Jun‐ya , Hamada Kazuki , Satoh Toshiyuki , Saga Norihiko
Published: June 2016

Many pneumatic actuators have been developed to be lightweight with high output for decreasing the impact force. However, for pneumatic actuators it is difficult to maintain exact control because these actuators have constraints. In this study, we developed model predictive control (MPC) that can accommodate these constraints when applied to the pneumatic actuator we developed. As described here, we compared and evaluated the control performance using MPC and proportional–integral–derivative (PID) control with an anti‐windup control system. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Optimum design of a regenerative braking system for electric vehicles based on fuzzy control strategy
Authors: Cao Xihang , Ishikawa Takeo
Published: June 2016

A regenerative braking system (RBS) can prolong the driving distance of electric vehicles by converting mechanical energy into electric energy. In this paper, an RBS based on fuzzy control strategy is proposed. By analyzing the characteristics of all factors, under the assurance of safety and stability during braking conditions, a fuzzy control model was established in the MATLAB/SIMULINK environment and verified by using simulation software Advisor2002. In order to recover more energy, the control model was optimized by the Taguchi method, and a new fuzzy control model was established and simulated. The simulation results show that by using the optimized fuzzy control system, more braking energy can be recovered and that the energy recovery efficiency can be increased. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
The association between pulse pressure change and cognition in late life: Age and where you start matters
Authors: McDade Eric , Sun Zhaowen , Lee Ching‐Wen , Snitz Beth , Hughes Tiffany , Chang Chung‐Chou H. , Ganguli Mary
Published: June 2016

Introduction

Variations across studies in the association between blood pressure (BP) and cognition might be explained partly by duration of exposure to hypertension and partly by nonrandom attrition over time. Pulse pressure (PP) reflects arterial stiffness which may better reflect chronicity of hypertension.

Methods

Over six annual cycles, 1954 individuals aged 65+ years from a prospective population‐based cohort underwent BP measurements and cognitive evaluations. We examined the relationship of change in five cognitive domains to longitudinal PP patterns across the late‐life age spectrum, before and after stratifying by baseline systolic blood pressure (SBP) and adjusting for attrition.

Results

There were four longitudinal PP patterns: stable normal, stable high, increasing, and decreasing. Those with lower baseline SBP and an increasing or stable high PP had less decline in cognition, an effect that was attenuated with aging. Among those with higher baseline SBP, there were no differences across PP groups, but increasing age was consistently associated with greater cognitive decline.

Discussion

The effect of PP on cognitive decline depends on age, baseline SBP, and the trajectory of PP change. Cardiovascular mechanisms underlying cognitive aging should be recognized as nuanced and dynamic processes when exploring prevention and treatment targets in the elderly, so that the optimal timing and type of intervention can be identified.
F.09 Neurosurgical Outcomes in patients with Multiple Sclerosis related Trigeminal Neuralgia
Authors: Krishnan S , Kaufmann AM
Published: June 2016

Background: The aim of this study was to assess the outcomes of surgery for multiple sclerosis-related trigeminal neuralgia (MS-TN). Methods: All Manitobans undergoing first surgery for medically refractory MS-TN between 2000 and 2014 were identified. The time interval until additional surgeries were required for recurrent pain, defined as the time to fail (TTF), was determined from a retrospective chart review. Kaplan-Meier analyses were performed and outcomes compared. Results: Twenty-one patients (26 sides) underwent first rhizotomy by GammaKnife (GK, 13), glycerol injection (PGR, 10) or balloon compression (BCR, 3). Second procedures were required in 88% at 15±13 months, including GK (24), PGR (19), BCR (25), microvascular decompression (2) and open surgical partial rhizotomy (Dandy, 4) for an overall total of 99 surgeries (1-12 per side). The additional GK, PGR, and BCR eventually failed and required further surgeries in 40%, 60% and 70% at 1, 2, and 3 years respectively with a trend to longer TTF compared to first surgeries (ns). Follow up of Dandy procedures, however, identified no pain recurrence at 4 to 110 months. Conclusions: The minimally invasive rhizotomies for MS-TN were associated with high rates of recurrence and reoperation. Long term pain relief was best achieved with a Dandy procedure, even after multiple prior rhizotomies.
F.10 Management of peripheral nerve sheath tumours: the Toronto Western Hospital experience
Authors: Guha D , Davidson B , Nadi M , Guha A , Zadeh G
Published: June 2016

Background: We retrospectively review benign peripheral nerve sheath tumours (BPNST) managed surgically at the Toronto Western Hospital. The incidence of BPNST is classified by anatomic location and predisposition syndrome. Independent predictors of tumour recurrence and symptom resolution are identified. Methods: 175 patients with 201 tumours were eligible for analysis. Data was collected on patient age, gender, diagnosis of neurofibromatosis (NF), tumour histopathology, tumour location, tumour volume, and extent of resection. Postoperative motor, sensory and pain outcomes were dichotomized as stable/improved or worse than preoperative scores. Relationships between tumour recurrence, or symptom resolution, and predictor variables were assessed with univariate and multiple logistic regression models. Results: Among Schwannomas, subtotal resection, a diagnosis of Schwannomatosis, and larger tumour volume were associated with recurrence (p=0.012, p=0.048, p=0.049, respectively); for neurofibromas, subtotal resection and a diagnosis of NF1 were associated with recurrence (p=0.036, p=0.022, respectively). Multivariate analyses revealed subtotal resection as an independent predictor of recurrence for BPNSTs (p=0.007, OR=13.16, 95%-CI 2.34-52.63). Gross-total resection (p=0.023, OR=4.01, 95%-CI 1.21-13.22) and presence of a preoperative motor deficit (p=0.038, OR=8.06, 95%-CI 4.65-90.91) were independent predictors of stable/improved postoperative motor function for BPNSTs. Conclusions: Gross-total resection is associated with both reduced recurrence and improved postoperative motor function, and should be attempted for all eligible BPNSTs.
P.009 Physician assisted death and the neurosurgeon
Authors: Barry SP , Fleetwood I , Reddy K , Ekong C , Gorman P , Wheelock B , Moulton R
Published: June 2016

Background: The Supreme Court of Canada (SCC) recently rendered a decision striking down the Criminal Code absolute prohibition on providing assisted dying. End of life decisions are commonly encountered by neurosurgeons due to the nature of their practice. Neurosurgeons will be faced with patients requesting PAD in the near future. Methods: The recent SCC ruling heralds a change that will radically alter a most basic tenet that has historically guided physicians and surgeons. A subcommittee of the Canadian Neurosurgical Society (CNSS) was formed to generate a position statement to reflect the interests of both neurosurgeons and their patients. Results: Fundamental issues regarding the implementation of PAD identified include:

Clarity of legislation

The creation of an independent, third party referral service

Effective safeguards and oversight of the entire process

-The right to “conscientious objection” on the part of hysicians who do not wish to be involved in PAD

Conclusions: The CNSS urges clarity in legislation regarding PAD and strict oversight in its implementation to reduce potential harm. We also support the creation of an independent, third party referral service which would serve to respect the conscience of those health care providers who do not wish to actively participate in PAD.
P.011 Evaluation of educational needs in neurology in the province of Quebec: a survey-based study
Authors: Gros P , Reiter-Campeau S , Hamad D , Carmant L
Published: June 2016

Background: In contrast with 56% of US medical schools, most Canadian medical schools do not offer a required clerkship neurology rotation. This study aims to assess the need for additional clinical neurology training in Quebec medical schools. Methods: Third and fourth year medical students from the province of Quebec completed surveys inquiring about accumulated theoretical teaching time, clinical neurology exposure, self-reported neurological examination proficiency and interest in additional training. Results: 66 students answered the survey. 43% were from Université de Montréal, 18 % from McGill University, 14% from Université Laval and 24% from Université de Sherbrooke. For theoretical teaching, 44% reported at least 60 hours (h) of teaching, 44% reported 40 to 60 h and 23% reported 10 to 40 h. For clinical exposure, 24% reported at least 60 h, 8% reported 40 to 60 h, 40% reported 10 to 40 h and 29% reported less than 10 h. Most students reported being comfortable with their neurological examination skills (58%) but still 41% were uncertain or felt uncomfortable. 80% indicated interest in receiving additional clinical exposure. Conclusions: Amongst Quebec medical students, clinical neurology exposure is likely insufficient. An important proportion of students remain uncomfortable with the neurological examination and most students are interested in additional neurological training.
P.016 Bimanual psychomotor performance in neurosurgical resident applicants assessed using NeuroVR (formerly NeuroTouch), a virtual reality simulator
Authors: Winkler-Schwartz A , Bajunaid K , Mullah M , Marwa I , Alotaibi F , Baggiani M , Azarnoush H , Al Zharni G , Christie S , Sabbagh A , Werthner P , Del Maestro R , Sawaya R
Published: June 2016

Background: Current selection methods for neurosurgical residents lack objective measurements of psychomotor performance. This pilot study was designed to answer three questions: 1) What are the differences in bimanual psychomotor performance among neurosurgical residency applicants using the NeuroVR (formerly NeuroTouch) neurosurgical simulator? 2) Are there exceptionally skilled medical student applicants? 3) Does previous surgical exposure influence surgical performance? Methods: Medical students attending neurosurgery residency interviews at McGill University were asked to participate. Participants were instructed to remove 3 simulated brain tumors. Validated tier 1, tier 2, and advanced tier 2 metrics were utilized to assess bimanual psychomotor performance. Demographic data included weeks of neurosurgical elective and prior operative exposure. Results: Sixteen of 17 neurosurgical applicants (94%) participated. Performances clustered in definable top, middle, and bottom groups with significant differences for all metrics. Increased time spent playing music, increase applicant self-evaluated technical skills, high self-ratings of confidence and increased skin closures statistically influenced performance on univariate analysis. A trend for both self-rated increased operating room confidence and increased weeks of neurosurgical exposure to increase blood loss was seen in multivariate analysis. Conclusions: Simulation technology identifies neurosurgical residency applicants at the extremes of technical ability and extrinsic and intrinsic applicant factors appear to influence performance.
P.019 Trends in medication use over eleven years in patients presenting to a rural and remote memory clinic
Authors: Verity R , Kirk A
Published: June 2016

Background: Anticholinergic and sedating medications are generally contraindicated in those with cognitive decline. We examined trends in medication use by patients presenting to a rural and remote memory clinic (RRMC) between March 2004 and June 2015 to determine whether patterns of medication use have changed. Methods: The first 445 patients seen at the RRMC between 2004 and 2015 were included in this analysis. Medication lists were collected at the patient’s initial visit, and it was noted whether patients were taking anticholinergic or potentially sedating drugs. Statistical analysis (Spearman’s Correlation) was conducted to examine trends in medication use over time. Results: Ninety-one patients (20.5%) were taking at least one anticholinergic medication. There was a statistically significant decline (25.0% in 2004 to 12.5% in 2014) in percentage of patients presenting with anticholinergic medications over the eleven years of this study (Spearman’s correlation coefficient=-0.64, p=0.035). Conclusions: The most encouraging statistic to come from this study is a decline in anticholinergic medication use in this rural population. Prescribers must be properly informed to ensure that the number of medications per patient does not continue to rise, that medications are used only as necessary, and that potentially deleterious medications are avoided.
P.021 Seizures among drivers in Newfoundland and Labrador
Authors: Aminian KS , Ogunyemi A , Coombs J
Published: June 2016

Background: Regulation of drivers licences aims to strike a balance between autonomy and public safety. In Newfoundland and Labrador, an individual experiencing seizures must have a 6-month seizure-free interval before a driving licence is reinstated, although exceptions apply. There is a paucity of data surrounding driving safety in people with epilepsy. Methods: The Department of Motor Vehicles and Registration extracted data from the charts of drivers experiencing seizures for the period between 2010-2014, inclusive. Two groups were examined: drivers aged 16-24 (n=104) and 75+ (n=115). Given that mandatory reporting is required in Newfoundland and Labrador, this theoretically represents a population-based study. Results: Overall, 5.1% of the population experienced a motor vehicle collision, and collisions were more frequent among younger drivers. Significantly more people in the 75+ category had a medical history that could have contributed to seizures. Only 37.6% of the overall sample had their first seizure reported. This was not different between age groups or seizure types (generalized vs. focal). Though the age groups differed with respect to seizure type, this did not affect driving safety, as measured by motor vehicle collisions and driving disobedience. Conclusions: We found a high rate of driving disobedience despite the requirement for mandatory reporting and seizure type did not affect driving safety.
P.022 Neuroimaging findings and seizure type as risk factors for adult focal drug resistant epilepsy
Authors: Hernandez-Ronquillo L , Lebony-Roy P , Buckley S , Tellez Zenteno J
Published: June 2016

Background: About 35% of patients with epilepsy may develop drug-resistant epilepsy (DRE). Identifying risk factors associated with DRE will allow us to identify earlier patients in the course of the disease. Methods: This is a case-control study nested within a cohort. Chart reviews of subjects who full fill inclusion criteria were completed. Inclusion criteria included age>18 years, focal epilepsy determined by clinical correlation and EEG. DRE was determined by ILAE criteria. Results: 149 subjects were included. Seventy had DRE (cases), and seventy-nine did not have DRE (controls). DRE group had a mean age of 41 years (SD+14.8) compared to the control group (49+17.5) (p=0.003). DRE group had a mean age at diagnosis of epilepsy of 19+15.3 compared to the control group with a mean of 33.6+21. (p=<0.001). The main risk factors identified in this study were; cortical dysplasia OR 8.67 (CI 1.04-72.3, p=0.026); mesial temporal sclerosis (MTS) (OR 2.69; CI 1.12-6.47; p=0.024); and presence of complex partial seizures (OR 2.04. Conclusions: Young age at diagnosis of focal epilepsy, diagnosis of cortical dysplasia, MTS, and presence of complex partial seizures are risk factors for DRE
P.024 Stimulus-Induced Rhythmic, Periodic or Ictal Discharges (SIRPIDs): associated factors and prognostic implications
Authors: Braksick S , Burkholder D , Spyridoula T , Martineau L , Mandrekar J , Rossetti A , Savard M , Britton J , Rabinstein A
Published: June 2016

Background: SIRPIDS were first described in 2004 in patients admitted in an intensive care unit. Despite few studies attempting to better characterize SIRPIDS, their pathophysiology and clinical implication remain uncertain. Methods: Adult patients hospitalized in an intensive care unit with alteration of consciousness who underwent EEG recording in three separate centers were included in this retrospective study. Demographic data and EEG findings were noted. Characteristics of SIRPIDS were documented. The main outcome measures included the incidence of SIRPIDS, association of SIRPIDS with mortality and other EEG characteristics, EEG and clinical predictors of mortality. Results: 416 patients were included and SIRPIDs were identified in 43 patients (10.3%). The proportion of patients with SIRPIDs was not significantly different across the three sites (p=0.3351). Anoxia (p=0.0009), antiepileptic medications (p=0.0109), electrographic seizures (p=0.0259), triphasic waves (p=0.0012) and epileptiform discharges (p=0.0242) were independently associated with the presence of SIRPIDs. Older age (p=0.0050), anoxia (p=<0.0001) and absence of EEG reactivity (p<0.0001), but not SIRPIDs (p=0.1668), were independently associated with in-hospital mortality. Conclusions: In critically ill patients undergoing EEG, SIRPIDs occurred in 10% and were associated with other electrographic abnormalities previously reported to indicate poor prognosis. SIRPIDs were not independently associated with in-hospital mortality.
P.029 Case report: Facial diplegia and aseptic meningitis in a 44 year-old man returning from Côte d’Ivoire
Authors: AlDhukair HA , Altman R , Parks A , Cheng MP , Damian A
Published: June 2016

Background: Bilateral facial paralysis is a rare manifestation of Human Immunodeficiency Virus (HIV). Few cases of HIV seroconversion syndrome presenting with aseptic meningitis and facial diplegia have been previously reported. Methods: Case Report. Case Description: A 44-year-old male with uncontrolled hypertension who presented with 5-day history of migrainous headache, bucco-labial dysarthria, meningismus and dysguesia. Three weeks prior to presentation, he suffered a transient febrile illness preceded by an unprotected sexual encounter while vacationing in Côte d’Ivoire. Examination was significant for hypertensive urgency, bilateral lower motor neuron (LMN) facial paralysis, and meningeal irritation. Investigations revealed acute on chronic renal impairment and left ventricular hypertrophy. Brain MRI (without contrast) revealed microhemorrhages with dystrophic calcifications and microangiopathic changes. CSF analysis revealed 55 WBC (lymphocytic), normal glucose, and 0.67g/L protein. The infectious work-up was positive for HIV, which was confirmed by Western Blot (WB). CD4 count was 176 cells/μL and the viral load was 419,289 copies/ml. Lyme antibodies were also positive by enzyme-linked immunosorbent assay (ELISA), but negative by WB. Discussion: Facial diplegia is a rare manifestation of HIV, and can be indicative of a seroconversion syndrome. This case illustrates another layer of complexity; deciphering acute from chronic systemic manifestations of hypertension, and appreciating falsely positive Lyme antibodies by ELISA during acute HIV seroconversion.
P.031 Lemierre’s syndrome - a rare disease with devastating complications
Authors: Alhusaini S , Althubait S , Melmed C , Sidel M
Published: June 2016

Background: Lemierre’s syndrome is a rare but serious complication of bacterial oropharyngeal infection. It is characterized by local spread of the primary infection, thrombophlebitis of the internal jugular vein, and septic metastases resulting in significant multi-system complications. Methods: A case report. Results: A previously healthy 63 year-old female presented to our emergency room with four-day history of sore throat, headache, fever and malaise. Initial examination revealed evidence of left tonsillar swelling and cervical lymphadenopathy. The patient rapidly deteriorated within hours of presentation and developed septic shock that was complicated by an acute kidney injury and disseminated intravascular coagulation (DIC). CT of the head and neck revealed a deep abscess within the left masticular triangle extending to surrounding soft tissue as well as C1-C3 epidural space. An extensive bilateral internal jugular vein thrombosis was noted; extending into the sigmoid and cavernous sinuses bilaterally. A thrombosis of the superior sagittal sinus and parafalcine subdural hematoma were also demonstrated. Blood cultures grew Group C Streptococcus. As the deep abscess was not amenable to surgical drainage, the patient was treated with broad-spectrum IV antibiotics. Anticoagulation was also commenced after management and resolution of the DIC. Conclusions: Lemierre’s syndrome remains relevant nowadays and awareness of its potential neurological complications is warranted.
P.034 Eye movement assessment and diffusion tensor imaging in patients with post concussion syndrome
Authors: Taghdiri F , Irwin SL , Multani N , Eizenman M , Tarazi A , Ebraheem A , Chung J , Khodadadi M , Goswami R , Wennberg R , Green R , Mikulis D , Tator C , Tartaglia MC
Published: June 2016

Background: Post concussion syndrome (PCS) can affect up to 30% of patients with concussion. Biomarkers of this condition would be beneficial for diagnosis and management. We hypothesized that eye tracking parameters would correlate with microstructural changes of white matter integrity, as measured by diffusion tensor imaging (DTI), in patients with PCS. Methods: Sixty patients with PCS and at least 2 concussions participated in our prospective study. Attention and executive function were tested using Visual Attention Scanning Technology (VAST). In a matching task, the normalized number of visits to master image before making the first selection is used as a surrogate of working memory. We related performance on VAST to white matter integrity using Tract-Based Spatial Statistics of diffusion tensor imaging data. Results: 60 participants (mean age 34.3 years, SD 13.8) had a mean of 4 concussions. There were negative correlations between fractional anisotropy (FA) of the genu, body, and splenium of the corpus callosum and normalized number of visits to master image before first selection (r=-0.432, p=0.001; r=-0.504, p<0.001; and r=-0.388, p=0.002; respectively). A negative correlation was also seen between right cingulum FA and the global processing index (r=-0.349, p=0.006). Conclusions: Impaired performance on eye tracking measures of attention and executive function may reflect alterations in white matter tracts.
P.039 New association of anti-Hu positive limbic encephalitis and sensory ganglionopathy with small cell gastric tumour
Authors: Ziller MG , Göttke EL , Bambonye M , Dalfen R
Published: June 2016

Background: While anti-Hu antibody associated encephalitis has been well-documented in association with a variety of neoplastic processes, paraneoplastic limbic encephalitis and sensory ganglionopathy with positive anti-Hu antibodies has not previously been linked in the literature with a neuroendocrine gastric tumour of advanced stage. Methods: Case report Results: We present the case of an 86-year old woman who developed behavioural changes, paroxysmal anxiety attacks and poor balance several months after being diagnosed with poorly differentiated gastric small cell tumour in a clinical setting of weight loss and anemia. Anti-Hu antibodies were present. MRI showed signal abnormalities in the right mesial temporal lobe with contrast enhancement. Paroxysmal lateralized EEG changes were recorded and EMG/NCS showed absent sensory nerve responses. Behavioural symptoms stabilized under treatment with intravenous immunoglobulins, but sensory ataxia continued to worsen. The patient declined further therapy and deceased two months after transfer to palliative care. Conclusions: To our knowledge, this is the first report linking small cell gastric tumour with limbic encephalitis, sensory ganglionopathy-associated ataxia and anti-Hu antibodies. This description further broadens the clinical spectrum of anti-Hu syndrome.
P.040 Redefining true leukocytosis in the traumatic lumbar puncture
Authors: Rizvi SA , Moien-Afshari F , Ghafarian M
Published: June 2016

Background: Clinicians rely on a correction formula (Predicted CSFWBC=CSFRBC×BloodWBC/ BloodRBC) to determine if a true CSF leukocytosis exists. This formula may overestimate true CSF leukocytosis leading to delayed diagnosis and treatment of meningitis. Methods: A retrospective review of CSF data of 105 patients registered at 3 hospitals (Saskatoon, Canada) between 2011-2013 who met the following criteria: 1) CSF samples from lumbar puncture (LP) contained≥1000 RBC/mm3; 2) a complete blood count (CBC) performed within 24 hours of LP; and 3) CSF not obtained due to high clinical suspicion of meningitis and was negative for microbial staining and culture. Regression analysis was performed to determine the relationship between actual and predicted CSF WBC values. Results: Mean adult age was 48.9 years; CSF profile (mean WBC 146.3×106/L; RBC 17374×106/L; glucose 4.1 mmol/L; protein 1.4 g/L); mean peripheral WBC 8.2×109/L; RBC 3.9×109/L. Mean pediatric age was 1.4 years; CSF profile (mean WBC 171.8; RBC 41763; glucose 2.7; protein 1.7); mean peripheral WBC 12; RBC 7.2. The observed LP CSF WBC value was 47% of predicted (r2=0.54 pediatric cohort; r2=0.91 adult cohort). Conclusions: True CSF leukocytosis in both pediatric and adult patients could be missed in a traumatic CSF sample if correction is based on current formulas. We propose a modifcation: ObservedCSFWBC=0.5×[CSFRBC×BloodWBC/BloodRBC].
P.051 Patient-reported adverse events on Multiple Sclerosis disease-modifying therapies in an urban tertiary MS clinic
Authors: Liao ZJ , Lee L , Carr K
Published: June 2016

Background: Disease-modifying therapies (DMT) have been shown to reduce relapses and delay disability in individuals with relapsing-remitting multiple sclerosis (MS). However, these medications can cause adverse events (AE) leading to poor adherence. To better understand their clinical utility, this study examined real-life experiences with DMT in a tertiary MS clinic. Methods: A retrospective chart review (1999-2015) was conducted to evaluate the prevalence of AE and discontinuation rates of Health Canada approved DMT. Results: 445 MS patients who have used at least one DMT in their lifetime were reviewed. Among first-line injectable therapies, interferon beta (IFNβ) 1-α IM users (49.6%) were most likely to report an AE. Flu-like reactions and injection site reactions were the most commonly reported AE. Among first-line oral therapies, BG-12 users (58.5%) were most likely to report an AE. The most common AE were flushing and gastrointestinal upset. DMT that were most frequently discontinued as a result of AE were IFNβ 1-α SC (39.3%), IFNβ 1-α IM (36.8%) and BG-12 (34.6%). Conclusions: The prevalence of AE and discontinuation rate were congruent. In comparison with recent literature, this study demonstrated lower prevalence of AE but equivocal or higher discontinuation rates. This discrepancy could represent a more realistic depiction of the impact that DMT AE have on patients.
P.052 Late-onset adrenoleukodystrophy mimicking primary progressive multiple sclerosis
Authors: Schabas AJ , Sayao A
Published: June 2016

Background: Adrenoleukodystrophy (ALD) is a peroxisomal disorder that leads to the accumulation of very long chain fatty acids in the body. Younger males typically present with a catastrophic cerebral demyelinating disease, while adult males tend to develop a progressive myelopathy and neuropathy. Methods: Case presentations and literature review. Results:Case1: A 58-year-old male with a three-year history of unsteady gait. His MRI showed multiple T2-hyperintensities most prominently in the posterior corpus collosum (which progressed over time) as well as spinal cord atrophy. Primary progressive multiple sclerosis (PPMS) was suspected. Case 2: The patient’s bother, a 49-year-old, had a ten-year history of difficulty walking. MRI findings included a single large T2 hyper-intensity spanning the anterior aspect of the corpus collosum and an atrophic spinal cord. Given the family history, both brothers were investigated for and diagnosed with ALD. Conclusions: Both cases are of males presenting with a progressive myelopathy in middle age. In the first case, the history, physical exam, and imaging findings were most consistent with PPMS. However, the second case was less typical for MS prompting further investigations. These cases highlight the need to have a broad differential when confronted with atypical cases of MS and reminds the clinician of the phenotypic variability of ADL.
P.054 The use of robotic technology to define post-operative neurological dysfunction in patients undergoing coronary bypass surgery: a feasibility study
Authors: Venters AL , Saha T , Hamilton A , Petsikas D , Scott S , Boyd GJ
Published: June 2016

Background: Cognitive dysfunction following coronary artery bypass surgery is a regular occurrence, but its cause is still unknown. In order to devise strategies to mitigate this acquired disability, a precise and quantitative description of the post-operative neurocognitive phenotype is necessary. This study is designed to assess the feasibility of using the KINARM robot to quantify the changes in the neurological function after cardaic surgery. Methods: Patients without prior history of cognitive dysfunction were recruited from the pre-operative cardiac surgery clinic, and underwent pre-operative assessment with the KINARM. The KINARM provides a quantitative assessment of the neurocognitive control of the upper limbs. During bypass surgery, brain tissue oxygen levels were measured with near-infrared spectroscopy. Patients were reassessed with the KINARM post-operatively at 3 months. Results: To date, 12 participants have been recruited (mean age = 65 years, all male). On straightforward tasks, such as visually guided reaching, the majority of patients scored within the normal range, both pre- and post-operatively. In more complex tasks, required visuospatial and executive functioning, post-operative deficits were more pronounced. Conclusions: It is feasible to use the KINARM robot to provide a quantitative measurement of the neurocognitive phenotype of patients after cardiac surgery.
P.060 A case of mononeuritis multiplex complicating Epstein-Barr virus infection
Authors: Villeneuve J , Khuong H , Dionne A
Published: June 2016

Background: Mononeuritis multiplex is a painful, asymmetrical peripheral neuropathy involving motor and sensory nerves. This neurological condition is classically associated with systemic diseases such as connective tissue disorders, vasculitis, hematologic diseases including cryoglobulinaemia and amyloidosis. It has also been reported infrequently as a paraneoplastic or post infectious disorder. Methods: Case report Results: We are reporting a case of a 35-year-old man who presented with mononeuritis multiplex following an infectious mononucleosis associated with a mixed cryoglobulinemia. He was treated with IVIG, IV pulse steroid and a prednisone taper over 7 months. Later on, he had a nerve transfer from FCR (flexor carpi radialis) to ECRB (extensor carpi radialis brevis) and PIN (posterior interosseous nerve) due to complete denervation of the PIN without evidence of spontaneous recovery. Conclusions: Acute EBV infection should be suspected in the setting of mononeuritis multiplex. This is the first reported case of nerve transfer for this type of nerve injury.
P.065 The impact of a risk algorithm on time-to-care: targeting triage for acute cerebrovascular syndrome (ACVS) patients in a rapid TIA clinic
Authors: Bibok M , Henri-Bhargava AR , Morrison J , Votova K , Penn AM
Published: June 2016

Background: Approximately, one-third of TIA clinics use the ABCD2 score to triage referrals. However, the usefulness of the score is limited because of its low specificity for non-cerebrovascular/mimic conditions. Timely access of referred patients to specialized TIA clinics may reduce recurrent stroke. Methods: The SpecTRA project implemented a novel electronic triage system in the TIA clinic that services Vancouver Island (BC), which replaced the existing ABCD2 triage model. A clinical classifier generating an ACVS probability score was calculated on the basis of the clinic referral form information. Next, a time-varying ABCD2-based risk score derived from Johnston et al. (2007) was calculated, which is then weighted by the ACVS probability score to produce a finalized triage score. Time-to-care was compared pre- (2013/14) and post- (2014/15) implementation. Results: One year results show a statistically significant improvement in that time-to-care for ACVS patients (ABCD2 4/5) was one day earlier with the new triage system (median= 4days since symptom onset; N=250) compared to the previous year (median=5days; N=255) (Mann-Whitney U=38130, p< 0.001). No difference in unit arrival times (median= 5days) for non-cerebrovascular patients was observed (Mann-Whitney U=5563, p= 0.15). Conclusions: The performance of our ACVS triage system highlights quality improvement potential in time-to-care for outpatient TIA clinics.
P.068 Reliability of EEG reactivity in assessment of comatose patients utilizing a standardized protocol
Authors: Al.Khateeb MO , Gofton T , Al.Thenayan E , Debicki D
Published: June 2016

Background: Electroencephalogram (EEG) is used in evaluating thalamocortical function in comatose patients. EEG reactivity is increasingly being recognized as a potentially important predictor of outcome in comatose patients. There are no existing guidelines or standardized testing for EEG reactivity assessment. We will report the use of a clinically implemented standardized reactivity testing protocol in comatose patients to determine accurate prognosis. Methods: In this retrospective study we report results from standardized reactivity testing from January 2016 to May 2016. Five stimuli (Calling name, clapping, nasal tickle, noxious stimulus, tracheal suctioning) were applied at one minute intervals in comatose patients of all etiologies. The EEG background reactivity will be analyzed by two independent electroencephalographers ad correlated to clinical outcome. Results: The methods for establishing EEG reactivity and the inter-rater reliability in determining EEG reactivity will be reported. Conclusions: EEG background reactivity is likely beneficial in determining prognosis. However, reliable methods for eliciting and determining EEG reactivity in comatose patients are necessary.