Search results for: nerve conduction studies
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 11348

Search results for: nerve conduction studies

11258 The Possible Role of the Endoneurial Fibroblast-like Cells in Resolution of the Endoneurial Edema Following Nerve Crush Injury

Authors: Faris M. Altaf, Abdullah M Elkeshy

Abstract:

Forty-two albino male rats aged between 30 and 40 days (weighted 200 g to 250 g) were used in the present study. The left sural nerves of 36 rats were subjected to crush injury at 1 to 6 weeks intervals using 6 animals at each interval. The right and left sural nerves of the rest 6 rats were used as a control. After 2 weeks of the crush injury, the endoneurium showed channel-like spaces that were lined by the fibroblast-like cells and collagen bundles. These channels contained degenerated myelin and were connected with the perivascular and subperineurial spaces. Some of the flattened fibroblast-like cells were arranged in several layers in the subperineurial and perivascular spaces, forming barrier-like cellular sheets localizing the endoneurial edema in these spaces. Fibroblast-like cells also wrapped the regenerating nerve fibers by their branching cytoplasmic processes. At the end of the third week, the flattened fibroblasts formed nearly continuous sheets in the subperineurial and perivascular spaces. Macrophages were frequently noticed between these cellular barrier-like sheets and in the subperineurial and perivascular spaces. Conclusion: it could be concluded that the endoneurial fibroblast-like cells form barrier-like cellular sheets that localized the endoneurial edema in the subperineurial and perivascular spaces and create also the endoneurial channel-like spaces containing degenerated myelin and endoneurial edema helping the resolution of such edema.

Keywords: sural nerve, endoneurial fibroblast-like cells, endoneurial edema, barrier-like and channel-like spaces

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11257 Chronic and Sub-Acute Lumbosacral Radiculopathies Behave Differently to Repeated Back Extension Exercises

Authors: Sami Alabdulwahab

Abstract:

Background: Repeated back extension exercises (RBEEs) are among the management options for symptoms associated with lumbosacral radiculopathy (LSR). RBEEs have been reported to cause changes in the distribution and intensity of radicular symptoms caused by possible compression/decompression of the compromised nerve root. Purpose: The purpose of this study was to investigate the effects of the RBEEs on the neurophysiology of the compromised nerve root and on standing mobility and pain intensity in patients with sub-acute and chronic LSR. Methods: A total of 40 patients with unilateral sub-acute/chronic lumbosacral radiculopathy voluntarily participated in the study; the patients performed 3 sets of 10 RBEEs in the prone position with 1 min of rest between the sets. The soleus H-reflex, standing mobility and pain intensity were recorded before and after the RBEEs. Results: The results of the study showed that the RBEEs significantly improved the H-reflex, standing mobility and pain intensity in patients with sub-acute LSR (p<0.01); there was not a significant improvement in the patients with chronic LSR (p<0.61). Conclusion: RBEEs in prone position is recommended for improving the neurophysiological function of the compromised nerve root and standing mobility in patients with sub-acute LSR. Implication: Sub-acute and chronic LSR responded differently to RBEEs. Sub-acute LSR appear to have flexible and movable disc structures, which could be managed with RBEEs.

Keywords: h-reflex, back extension, lumbosacral radiculopathy, pain

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11256 Functional Outcome of Speech, Voice and Swallowing Following Excision of Glomus Jugulare Tumor

Authors: B. S. Premalatha, Kausalya Sahani

Abstract:

Background: Glomus jugulare tumors arise within the jugular foramen and are commonly seen in females particularly on the left side. Surgical excision of the tumor may cause lower cranial nerve deficits. Cranial nerve involvement produces hoarseness of voice, slurred speech, and dysphagia along with other physical symptoms, thereby affecting the quality of life of individuals. Though oncological clearance is mainly emphasized on while treating these individuals, little importance is given to their communication, voice and swallowing problems, which play a crucial part in daily functioning. Objective: To examine the functions of voice, speech and swallowing outcomes of the subjects, following excision of glomus jugulare tumor. Methods: Two female subjects aged 56 and 62 years had come with a complaint of change in voice, inability to swallow and reduced clarity of speech following surgery for left glomus jugulare tumor were participants of the study. Their surgical information revealed multiple cranial nerve palsies involving the left facial, left superior and recurrent branches of the vagus nerve, left pharyngeal, left soft palate, left hypoglossal and vestibular nerves. Functional outcomes of voice, speech and swallowing were evaluated by perceptual and objective assessment procedures. Assessment included the examination of oral structures and functions, dysarthria by Frenchey dysarthria assessment, cranial nerve functions and swallowing functions. MDVP and Dr. Speech software were used to evaluate acoustic parameters of voice and quality of voice respectively. Results: The study revealed that both the subjects, subsequent to excision of glomus jugulare tumor, showed a varied picture of affected oral structure and functions, articulation, voice and swallowing functions. The cranial nerve assessment showed impairment of the vagus, hypoglossal, facial and glossopharyngeal nerves. Voice examination indicated vocal cord paralysis associated with breathy quality of voice, weak voluntary cough, reduced pitch and loudness range, and poor respiratory support. Perturbation parameters as jitter, shimmer were affected along with s/z ratio indicative of voice fold pathology. Reduced MPD(Maximum Phonation Duration) of vowels indicated that disturbed coordination between respiratory and laryngeal systems. Hypernasality was found to be a prominent feature which reduced speech intelligibility. Imprecise articulation was seen in both the subjects as the hypoglossal nerve was affected following surgery. Injury to vagus, hypoglossal, gloss pharyngeal and facial nerves disturbed the function of swallowing. All the phases of swallow were affected. Aspiration was observed before and during the swallow, confirming the oropharyngeal dysphagia. All the subsystems were affected as per Frenchey Dysarthria Assessment signifying the diagnosis of flaccid dysarthria. Conclusion: There is an observable communication and swallowing difficulty seen following excision of glomus jugulare tumor. Even with complete resection, extensive rehabilitation may be necessary due to significant lower cranial nerve dysfunction. The finding of the present study stresses the need for involvement of as speech and swallowing therapist for pre-operative counseling and assessment of functional outcomes.

Keywords: functional outcome, glomus jugulare tumor excision, multiple cranial nerve impairment, speech and swallowing

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11255 Resistive Switching in TaN/AlNx/TiN Cell

Authors: Hsin-Ping Huang, Shyankay Jou

Abstract:

Resistive switching of aluminum nitride (AlNx) thin film was demonstrated in a TaN/AlNx/TiN memory cell that was prepared by sputter deposition techniques. The memory cell showed bipolar switching of resistance between +3.5 V and –3.5 V. The resistance ratio of high resistance state (HRS) to low resistance state (HRS), RHRS/RLRS, was about 2 over 100 cycles of endurance test. Both the LRS and HRS of the memory cell exhibited ohmic conduction at low voltages and Poole-Frenkel emission at high voltages. The electrical conduction in the TaN/AlNx/TiN memory cell was possibly attributed to the interactions between charges and defects in the AlNx film.

Keywords: aluminum nitride, nonvolatile memory, resistive switching, thin films

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11254 A New Analytic Solution for the Heat Conduction with Time-Dependent Heat Transfer Coefficient

Authors: Te Wen Tu, Sen Yung Lee

Abstract:

An alternative approach is proposed to develop the analytic solution for one dimensional heat conduction with one mixed type boundary condition and general time-dependent heat transfer coefficient. In this study, the physic meaning of the solution procedure is revealed. It is shown that the shifting function takes the physic meaning of the reciprocal of Biot function in the initial time. Numerical results show the accuracy of this study. Comparing with those given in the existing literature, the difference is less than 0.3%.

Keywords: analytic solution, heat transfer coefficient, shifting function method, time-dependent boundary condition

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11253 Atypical Familial Amyotrophic Lateral Sclerosis Secondary to Superoxide Dismutase 1 Gene Mutation With Coexistent Axonal Polyneuropathy: A Challenging Diagnosis

Authors: Seraj Makkawi, Abdulaziz A. Alqarni, Himyan Alghaythee, Suzan Y. Alharbi, Anmar Fatani, Reem Adas, Ahmad R. Abuzinadah

Abstract:

Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, is a neurodegenerative disease that involves both the upper and lower motor neurons. Familial ALS, including superoxide dismutase 1 (SOD1) mutation, accounts for 5-10% of all cases of ALS. Typically, the symptoms of ALS are purely motor, though coexistent sensory symptoms have been reported in rare cases. In this report, we describe the case of a 47- year-old man who presented with progressive bilateral lower limb weakness and numbness for the last four years. A nerve conduction study (NCS) showed evidence of coexistent axonal sensorimotor polyneuropathy in addition to the typical findings of ALS in needle electromyography. Genetic testing confirmed the diagnosis of familial ALS secondary to the SOD1 genetic mutation. This report highlights that the presence of sensory symptoms should not exclude the possibility of ALS in an appropriate clinical setting.

Keywords: Saudi Arabia, polyneuropathy, SOD1 gene mutation, familial amyotrophic lateral sclerosis, amyotrophic lateral sclerosis

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11252 Effect of Different Local Anesthetic Agents on Physiological Parameters and Vital Signs during Extraction in Children

Authors: Rasha F. Sharaf

Abstract:

Administration of local anesthesia for a child is considered a painful procedure, which affects his vital signs, physiological parameters, and his further attitude in the dental clinic. During the extraction of mandibular molars, the nerve block technique is the most commonly used for the administration of local anesthesia; however, this technique requires deep penetration of the needle, which causes pain and discomfort for the child. Therefore, the inferior alveolar nerve block technique can be substituted with an infiltration technique which is not painful if a potent anesthetic solutions will be used. In the current study, the effect of Articaine 4% will be compared to Mepivacaine 2%, and their influence on the vital signs of the child, as well as their ability to control pain during extraction, will be assessed.

Keywords: anesthesia, articaine, pain control, extraction

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11251 Investigation of Heat Transfer Mechanism Inside Shell and Tube Latent Heat Thermal Energy Storage Systems

Authors: Saeid Seddegh, Xiaolin Wang, Alan D. Henderson, Dong Chen, Oliver Oims

Abstract:

The main objective of this research is to study the heat transfer processes and phase change behaviour of a phase change material (PCM) in shell and tube latent heat thermal energy storage (LHTES) systems. The thermal behaviour in a vertical and horizontal shell-and-tube heat energy storage system using a pure thermal conduction model and a combined conduction-convection heat transfer model is compared in this paper. The model is first validated using published experimental data available in literature and then used to study the temperature variation, solid-liquid interface, phase distribution, total melting and solidification time during melting and solidification processes of PCMs. The simulated results show that the combined convection and conduction model can better describe the energy transfer in PCMs during melting process. In contrast, heat transfer by conduction is more significant during the solidification process since the two models show little difference. Also, it was concluded that during the charging process for the horizontal orientation, convective heat transfer has a strong effect on melting of the upper part of the solid PCM and is less significant during melting of the lower half of the solid PCM. However, in the vertical orientation, convective heat transfer is the same active during the entire charging process. In the solidification process, the thermal behavior does not show any difference between horizontal and vertical systems.

Keywords: latent heat thermal energy storage, phase change material, natural convection, melting, shell and tube heat exchanger, melting, solidification

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11250 Analysis of Combined Heat Transfer through the Core Materials of VIPs with Various Scattering Properties

Authors: Jaehyug Lee, Tae-Ho Song

Abstract:

Vacuum insulation panel (VIP) can achieve very low thermal conductivity by evacuating its inner space. Heat transfer in the core materials of highly-evacuated VIP occurs by conduction through the solid structure and radiation through the pore. The effect of various scattering modes in combined conduction-radiation in VIP is investigated through numerical analysis. The discrete ordinates interpolation method (DOIM) incorporated with the commercial code FLUENT® is employed. It is found that backward scattering is more effective in reducing the total heat transfer while isotropic scattering is almost identical with pure absorbing/emitting case of the same optical thickness. For a purely scattering medium, the results agree well with additive solution with diffusion approximation, while a modified term is added in the effect of optical thickness to backward scattering is employed. For other scattering phase functions, it is also confirmed that backwardly scattering phase function gives a lower effective thermal conductivity. Thus, the materials with backward scattering properties, with radiation shields are desirable to lower the thermal conductivity of VIPs.

Keywords: combined conduction and radiation, discrete ordinates interpolation method, scattering phase function, vacuum insulation panel

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11249 Revisiting the Surgical Approaches to Decompression in Quadrangular Space Syndrome: A Cadaveric Study

Authors: Sundip Charmode, Simmi Mehra, Sudhir Kushwaha, Shalom Philip, Pratik Amrutiya, Ranjna Jangal

Abstract:

Introduction: Quadrangular space syndrome involves compression of the axillary nerve and posterior circumflex humeral artery and its management in few cases, requires surgical decompression. The current study reviews the surgical approaches used in the decompression of neurovascular structures and presents our reflections and recommendations. Methods: Four human cadavers, in the Department of Anatomy were used for dissection of the Axillae and the Scapular region by the senior residents of the Department of Anatomy and Department of Orthopedics, who dissected quadrangular space in the eight upper limbs, using anterior and posterior surgical approaches. Observations: Posterior approach to identify the quadrangular space and secure its contents was recognized as the easier and much quicker method by both the Anatomy and Orthopedic residents, but it may result in increased postoperative morbidity. Whereas the anterior (Delto-pectoral) approach involves more skill but reduces postoperative morbidity. Conclusions: Anterior (Delto-pectoral) approach with suggested modifications can prove as an effective method in surgical decompression of quadrangular space syndrome. The authors suggest more cadaveric studies to facilitate anatomists and surgeons with the opportunities to practice and evaluate older and newer surgical approaches.

Keywords: surgical approach, anatomical approach, decompression, axillary nerve, quadrangular space

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11248 Transient Current Investigations in Liquid Crystalline Polyurethane

Authors: Jitendra Kumar Quamara, Sohan Lal, Pushkar Raj

Abstract:

Electrical conduction behavior of liquid crystalline polyurethane (LCPU) has been investigated under transient conditions in the operating temperature range 50-220°C at various electric fields of 4.35-43.45 kV/cm. The transient currents show the hyperbolic decay character and the decay exponent ∆t (one tenth decay time) dependent on field as well as on temperature. The increase in I0/Is values (where I0 represents the current observed immediately after applying the voltage and Is represents the steady state current) and the variation of mobility at high operating temperatures shows the appearance of mesophase. The origin of transient currents has been attributed to the dipolar nature of carbonyl (C=O) groups in the main chain of LCPU and the trapping charge carriers.

Keywords: electrical conduction, transient current, liquid crystalline polymers, mesophase

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11247 Numerical Investigation of Thermal Energy Storage System with Phase Change Materials

Authors: Mrityunjay Kumar Sinha, Mayank Srivastava

Abstract:

The position of interface and temperature variation of phase change thermal energy storage system under constant heat injection and radiative heat injection is analysed during charging/discharging process by Heat balance integral method. The charging/discharging process is solely governed by conduction. Phase change material is kept inside a rectangular cavity. Time-dependent fixed temperature and radiative boundary condition applied on one wall, all other walls are thermally insulated. Interface location and temperature variation are analysed by using MATLAB.

Keywords: conduction, melting/solidification, phase change materials, Stefan’s number

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11246 Modeling of Bioelectric Activity of Nerve Cells Using Bond Graph Method

Authors: M. Ghasemi, F. Eskandari, B. Hamzehei, A. R. Arshi

Abstract:

Bioelectric activity of nervous cells might be changed causing by various factors. This alteration can lead to unforeseen circumstances in other organs of the body. Therefore, the purpose of this study was to model a single neuron and its behavior under an initial stimulation. This study was developed based on cable theory by means of the Bond Graph method. The numerical values of the parameters were derived from empirical studies of cellular electrophysiology experiments. Initial excitation was applied through square current functions, and the resulted action potential was estimated along the neuron. The results revealed that the model was developed in this research adapted with the results of experimental studies and demonstrated the electrical behavior of nervous cells properly.

Keywords: bond graph, stimulation, nervous cells, modeling

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11245 Anatomical Characteristics of Superior Gluteal Artery

Authors: Nawaf Al-Kharashi, Waseem Al-Talalwah, Shorok Al Dorazi, Roger Soames

Abstract:

Superior gluteal artery is one of the largest branches of posterior division of the internal iliac artery. It passes between the lumbosacral and first sacral root to escape from the pelvic cavity through the grater sciatic foramen just above the piriformis. The current study includes 41 cadaver investigates the origin and branch of the superior gluteal artery and clarify the clinical significance. In present study, the superior gluteal artery arises from the posterior division of the internal iliac artery directly in 82.5% whereas it arises indirectly as from the sciatic artery in 15.9%. However, it is congenital absence in 1.6% which is compensated by sciatic artery. The sciatic nerve gains vascular supply from superior gluteal artery in two ways either during its course or giving lateral sacral artery in 27% and lumbar branches in 1.6%. It also supplies the adductors group and iliacus via giving obturator artery in 14.3% and in 1.6% respectively. The superior gluteal artery usually passes between lumbosacral trunk and first sacral root in 82.5% whereas it does not passes the sciatic roots as it arises behind them in 15.9%. With a variability of the superior gluteal artery origin, there is a variability of sciatic nerve roots supply. Further, the superior gluteal artery arising from sciatic artery behind the sciatic roots carries a high risk of intra-pelvic bleeding in case of posterior pelvic fracture. Prolonged ligation of the superior gluteal artery which gives lateral sacral artery may result in sciatic neuropathy. Therefore, surgeons have to be aware of the superior gluteal artery variation in origin, course and branches to reduce the iatrogenic faults.

Keywords: internal pudendal artery, inferior gluteal artery, superior gluteal artery, internal iliac artery. sciatic neuropathy, sciatic nerve

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11244 Continuous-Time Analysis And Performance Assessment For Digital Control Of High-Frequency Switching Synchronous Dc-Dc Converter

Authors: Rihab Hamdi, Amel Hadri Hamida, Ouafae Bennis, Sakina Zerouali

Abstract:

This paper features a performance analysis and robustness assessment of a digitally controlled DC-DC three-cell buck converter associated in parallel, operating in continuous conduction mode (CCM), facing feeding parameters variation and loads disturbance. The control strategy relies on the continuous-time with an averaged modeling technique for high-frequency switching converter. The methodology is to modulate the complete design procedure, in regard to the existence of an instantaneous current operating point for designing the digital closed-loop, to the same continuous-time domain. Moreover, the adopted approach is to include a digital voltage control (DVC) technique, taking an account for digital control delays and sampling effects, which aims at improving efficiency and dynamic response and preventing generally undesired phenomena. The results obtained under load change, input change, and reference change clearly demonstrates an excellent dynamic response of the proposed technique, also as provide stability in any operating conditions, the effectiveness is fast with a smooth tracking of the specified output voltage. Simulations studies in MATLAB/Simulink environment are performed to verify the concept.

Keywords: continuous conduction mode, digital control, parallel multi-cells converter, performance analysis, power electronics

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11243 Effects of Carbon Black/Graphite Ratio for Electrical Conduction and Frictional Resistance of Nanocomposite Sol-Gel Coatings

Authors: Julien Acquadro, Sophie Noel, Frédéric Houze, Philippe Teste, Pascal Chretien, Clément Genet, Edouard Breniaux, Marie-Joël Menu, Florence Ansart, Marie Gressier

Abstract:

This paper presents the study results of the electrical and tribological properties of nanocomposite hybrid sol-gel coatings developed for industrial applications on electrical connector housings. The electrical properties of coatings are provided by conductive fillers. The coatings presented in this study are formulated with different types of conductive carbon fillers, in this case carbon black and graphite particles. The coatings are deposited on a high-phosphorous nickel substrate by a dip-coating process. The authors have investigated the effects of the carbon black/graphite ratio on the coating's electrical and tribological properties. Electrical characterizations with a 4-probe method and AFM measurements as well as tribological tests by micro-friction shed light on the role of the black carbon/graphite ratio on the final properties of the sol-gel nanocomposite coatings. This study shows that the amount of carbon black mainly drives the coatings' electrical conduction property, while graphite's lubrication properties bring interest to reduce the values of friction coefficients (at a contact pressure of 800 MPa). In the industrial field of electrical connectors, such coatings aim at replacing cadmium and chromium (VI) protection, as recommended by REACH (Registration, Evaluation and Authorization of Chemicals) and RoHS (Restriction of Hazardous Substances in electrical and electronic equipment) regulations (Annex XVII of REACH).

Keywords: carbon conductive fillers, electrical conduction, sol-gel coatings, tribology

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11242 Electron Spin Resonance of Conduction and Spin Waves Dynamics Investigations in Bi-2223 Superconductor for Decoding Pairing Mechanism

Authors: S. N. Ekbote, G. K. Padam, Manju Arora

Abstract:

Electron spin resonance (ESR) spectroscopic investigations of (Bi, Pb)₂Sr₂Ca₂Cu₃O₁₀₋ₓ (Bi-2223) bulk samples were carried out in both the normal and superconducting states. A broad asymmetric resonance signal with side signals is obtained in the normal state, and all of them disappear in the superconducting state. The temperature and angular orientation effects on these signals suggest that the broad asymmetric signal arises from electron spin resonance of conduction electrons (CESR) and the side signals from exchange interactions as Platzman-Wolff type spin waves. The disappearance of CESR and spin waves in a superconducting state demonstrates the role of exchange interactions in Cooper pair formation.

Keywords: Bi-2223 superconductor, CESR, ESR, exchange interactions, spin waves

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11241 Posterior Thigh Compartment Syndrome Associated with Hamstring Avulsion and Antiplatelet Therapy

Authors: Andrea Gatti, Federica Coppotelli, Ma Primavera, Laura Palmieri, Umberto Tarantino

Abstract:

Aim of study: Scientific literature is scarce of studies and reviews valuing the pros and cons of the paratricipital approach for the treatment of humeral shaft fractures; the lateral paratricipital approach is a valid alternative to the classical posterior approach to the humeral shaft as it preserves both the triceps muscle and the elbow extensor mechanisms; based on our experience, this retrospective analysis aims at analyzing outcome, risks and benefits of the lateral paratricipital approach for humeral shaft fractures. Methods: Our study includes 14 patients treated between 2018 and 2019 for unilateral humeral shaft fractures: 13 with a B1 or B2 and a patient with a C fracture type (according to the AO/ATO Classification); 6 of our patients identified as male while 8 as female; age average was 57.8 years old (range 21-73 years old). A lateral paratricipital approach was performed on all 14 patients, sparing the triceps muscle by avoiding the olecranon osteotomy and by assessing the integrity and the preservation of the radial nerve; the humeral shaft fracture osteosynthesis was performed by means of plates and screws. After surgery all patients have started elbow functional rehabilitation with acceptable pain management. Post-operative follow-up has been carried out by assessing radiographs, MEPS (Mayo Elbow Performance Score) and DASH (Disability of Arm Shoulder and Hand) functional assessment and ROM of the affected joint. Results: All 14 patients had an optimal post-operative follow-up with an adequate osteosynthesis and functional rehabilitations by entirely preserving the operated elbow joint; the mean elbow ROM was 0-118.6 degree (range of 0-130) while the average MEPS score was 86 (range75-100) and 79.9 for the DASH (range 21.7-86.1). Just 2 patients suffered of temporary radial nerve apraxia, healed in the subsequent follow-ups. CONCLUSION: The lateral paratricipital approach preserve both the integrity of the triceps muscle and the elbow biomechanism but we do strongly recommend additional studies to be carried out to highlight differences between it and the classical posterior approach in treating humeral shaft fractures.

Keywords: paratricepital approach, humerus shaft fracture, posterior approach humeral shaft, paratricipital postero-lateral approach

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11240 Dielectric Behavior of 2D Layered Insulator Hexagonal Boron Nitride

Authors: Nikhil Jain, Yang Xu, Bin Yu

Abstract:

Hexagonal boron nitride (h-BN) has been used as a substrate and gate dielectric for graphene field effect transistors (GFETs). Using a graphene/h-BN/TiN (channel/dielectric/gate) stack, key material properties of h-BN were investigated i.e. dielectric strength and tunneling behavior. Work function difference between graphene and TiN results in spontaneous p-doping of graphene through a multi-layer h-BN flake. However, at high levels of current stress, n-doping of graphene is observed, possibly due to the charge transfer across the thin h-BN multi layer. Neither Direct Tunneling (DT) nor Fowler-Nordheim Tunneling (FNT) was observed in TiN/h-BN/Au hetero structures with h-BN showing two distinct volatile conduction states before breakdown. Hexagonal boron nitride emerges as a material of choice for gate dielectrics in GFETs because of robust dielectric properties and high tunneling barrier.

Keywords: graphene, transistors, conduction, hexagonal boron nitride, dielectric strength, tunneling

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11239 Two-Dimensional Modeling of Seasonal Freeze and Thaw in an Idealized River Bank

Authors: Jiajia Pan, Hung Tao Shen

Abstract:

Freeze and thaw occurs seasonally in river banks in northern countries. Little is known on how the riverbank soil temperature responds to air temperature changes and how freeze and thaw develops in a river bank seasonally. This study presents a two-dimensional heat conduction model for numerical investigations of seasonal freeze and thaw processes in an idealized river bank. The model uses the finite difference method and it is convenient for applications. The model is validated with an analytical solution and a field case with soil temperature distributions. It is then applied to the idealized river bank in terms of partially and fully saturated conditions with or without ice cover influence. Simulated results illustrate the response processes of the river bank to seasonal air temperature variations. It promotes the understanding of freeze and thaw processes in river banks and prepares for further investigation of frost and thaw impacts on riverbank stability.

Keywords: freeze and thaw, riverbanks, 2D model, heat conduction

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11238 Intracranial Hypertension without CVST in Apla Syndrome: An Unique Association

Authors: Camelia Porey, Binaya Kumar Jaiswal

Abstract:

BACKGROUND: Antiphospholipid antibody (APLA) syndrome is an autoimmune disorder predisposing to thrombotic complications affecting CNS either by arterial vasooclusion or venous thrombosis. Cerebral venous sinus thrombosis (CVST) secondarily causes raised intracranial pressure (ICP). However, intracranial hypertension without evidence of CVST is a rare entity. Here we present two cases of elevated ICP with absence of identifiable CVST. CASE SUMMARY: Case 1, 28-year female had a 2 months history of holocranial headache followed by bilateral painless vision loss reaching lack of light perception over 20 days. CSF opening pressure was elevated. Fundoscopy showed bilateral grade 4 papilledema. MRI revealed a partially empty sella with bilateral optic nerve tortuosity. Idiopathic intracranial hypertension (IIH) was diagnosed. With acetazolamide, there was complete resolution of the clinical and radiological abnormalities. 5 months later she presented with acute onset right-sided hemiparesis. MRI was suggestive of acute left MCA infarct.MR venogram was normal. APLA came positive with high titres of Anticardiolipin and Beta 2 glycoprotein both IgG and IgM. Case 2, 23-year female, presented with headache and diplopia of 2 months duration. CSF pressure was elevated and Grade 3 papilledema was seen. MRI showed bilateral optic nerve hyperintensities with nerve head protrusion with normal MRV. APLA profile showed elevated beta 2 glycoprotein IgG and IgA. CONCLUSION: This is an important non thrombotic complication of APLA syndrome and requires further large-scale study for insight into the pathogenesis and early recognition to avoid future complications.

Keywords: APLA syndrome, idiopathic intracranial hypertension, MR venogram, papilledema

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11237 Increasing Access to Upper Limb Reconstruction in Cervical Spinal Cord Injury

Authors: Michelle Jennett, Jana Dengler, Maytal Perlman

Abstract:

Background: Cervical spinal cord injury (SCI) is a devastating event that results in upper limb paralysis, loss of independence, and disability. People living with cervical SCI have identified improvement of upper limb function as a top priority. Nerve and tendon transfer surgery has successfully restored upper limb function in cervical SCI but is not universally used or available to all eligible individuals. This exploratory mixed-methods study used an implementation science approach to better understand these factors that influence access to upper limb reconstruction in the Canadian context and design an intervention to increase access to care. Methods: Data from the Canadian Institute for Health Information’s Discharge Abstracts Database (CIHI-DAD) and the National Ambulatory Care Reporting System (NACRS) were used to determine the annual rate of nerve transfer and tendon transfer surgeries performed in cervical SCI in Canada over the last 15 years. Semi-structured interviews informed by the consolidated framework for implementation research (CFIR) were used to explore Ontario healthcare provider knowledge and practices around upper limb reconstruction. An inductive, iterative constant comparative process involving descriptive and interpretive analyses was used to identify themes that emerged from the data. Results: Healthcare providers (n = 10 upper extremity surgeons, n = 10 SCI physiatrists, n = 12 physical and occupational therapists working with individuals with SCI) were interviewed about their knowledge and perceptions of upper limb reconstruction and their current practices and discussions around upper limb reconstruction. Data analysis is currently underway and will be presented. Regional variation in rates of upper limb reconstruction and trends over time are also currently being analyzed. Conclusions: Utilization of nerve and tendon transfer surgery to improve upper limb reconstruction in Canada remains low. There are a complex array of interrelated individual-, provider- and system-level barriers that prevent individuals with cervical SCI from accessing upper limb reconstruction. In order to offer equitable access to care, a multi-modal approach addressing current barriers is required.

Keywords: cervical spinal cord injury, nerve and tendon transfer surgery, spinal cord injury, upper extremity reconstruction

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11236 Minimally Invasive Open Lumbar Discectomy with Nucleoplasty and Annuloplasty as a Technique for Effective Reduction of Both Axial and Radicular Pain

Authors: Wael Elkholy, Ashraf Sakr, Mahmoud Qandeel, Adam Elkholy

Abstract:

Lumbar disc herniation is a common pathology that may cause significant low back pain and radicular pain that could profoundly impair daily life activities of individuals. Patients who undergo surgical treatment for lumbar disc herniation usually present with radiculopathy along with low back pain (LBP) instead of radiculopathy alone. When discectomy is performed, improvement in leg radiating pain is observed due to spinal nerve irritation. However, long-term LBP due to degenerative changes in the disc may occur postoperatively. In addition, limited research has been reported on the short-term (within 1 year) improvement in LBP after discectomy. In this study we would like to share our minimally invasive open technique for lumbar discectomy with annuloplasty and nuceloplasty as a technique for effective reduction of both axial and radicular pain.

Keywords: nucleoplasty, sinuvertebral nerve cauterization, annuloplasty, discogenic low back pain, axial pain, radicular pain, minimally invasive lumbar discectomy

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11235 Effects of Heart Rate Variability Biofeedback to Improve Autonomic Nerve Function, Inflammatory Response and Symptom Distress in Patients with Chronic Kidney Disease: A Randomized Control Trial

Authors: Chia-Pei Chen, Yu-Ju Chen, Yu-Juei Hsu

Abstract:

The prevalence and incidence of end-stage renal disease in Taiwan ranks the highest in the world. According to the statistical survey of the Ministry of Health and Welfare in 2019, kidney disease is the ninth leading cause of death in Taiwan. It leads to autonomic dysfunction, inflammatory response and symptom distress, and further increases the damage to the structure and function of the kidneys, leading to increased demand for renal replacement therapy and risks of cardiovascular disease, which also has medical costs for the society. If we can intervene in a feasible manual to effectively regulate the autonomic nerve function of CKD patients, reduce the inflammatory response and symptom distress. To prolong the progression of the disease, it will be the main goal of caring for CKD patients. This study aims to test the effect of heart rate variability biofeedback (HRVBF) on improving autonomic nerve function (Heart Rate Variability, HRV), inflammatory response (Interleukin-6 [IL-6], C reaction protein [CRP] ), symptom distress (Piper fatigue scale, Pittsburgh Sleep Quality Index [PSQI], and Beck Depression Inventory-II [BDI-II] ) in patients with chronic kidney disease. This study was experimental research, with a convenience sampling. Participants were recruited from the nephrology clinic at a medical center in northern Taiwan. With signed informed consent, participants were randomly assigned to the HRVBF or control group by using the Excel BINOMDIST function. The HRVBF group received four weekly hospital-based HRVBF training, and 8 weeks of home-based self-practice was done with StressEraser. The control group received usual care. We followed all participants for 3 months, in which we repeatedly measured their autonomic nerve function (HRV), inflammatory response (IL-6, CRP), and symptom distress (Piper fatigue scale, PSQI, and BDI-II) on their first day of study participation (baselines), 1 month, and 3 months after the intervention to test the effects of HRVBF. The results were analyzed by SPSS version 23.0 statistical software. The data of demographics, HRV, IL-6, CRP, Piper fatigue scale, PSQI, and BDI-II were analyzed by descriptive statistics. To test for differences between and within groups in all outcome variables, it was used by paired sample t-test, independent sample t-test, Wilcoxon Signed-Rank test and Mann-Whitney U test. Results: Thirty-four patients with chronic kidney disease were enrolled, but three of them were lost to follow-up. The remaining 31 patients completed the study, including 15 in the HRVBF group and 16 in the control group. The characteristics of the two groups were not significantly different. The four-week hospital-based HRVBF training combined with eight-week home-based self-practice can effectively enhance the parasympathetic nerve performance for patients with chronic kidney disease, which may against the disease-related parasympathetic nerve inhibition. In the inflammatory response, IL-6 and CRP in the HRVBF group could not achieve significant improvement when compared with the control group. Self-reported fatigue and depression significantly decreased in the HRVBF group, but they still failed to achieve a significant difference between the two groups. HRVBF has no significant effect on improving the sleep quality for CKD patients.

Keywords: heart rate variability biofeedback, autonomic nerve function, inflammatory response, symptom distress, chronic kidney disease

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11234 Nitrogen-Doped Ultrananocrystalline Diamond/Hydrogenated Amorphous Carbon Composite Films Prepared by Coaxial Arc Plasma Deposition

Authors: Abdelrahman Zkria, Tsuyoshi Yoshitake

Abstract:

Diamond is one of the most interesting semiconducting carbon materials owing to its unique physical and chemical properties, yet its application in electronic devices is limited due to the difficulty of realizing n-type conduction by nitrogen doping. In contrast Ultrananocrystalline diamond with diamond grains of about 3–5 nm in diameter have attracted much attention for device-oriented applications because they may enable the realization of n-type doping with nitrogen. In this study, nitrogen-doped Ultra-Nanocrystalline diamond films were prepared by coaxial arc plasma deposition (CAPD) method, the nitrogen content was estimated by X-ray photoemission spectroscopy (XPS). The electrical conductivity increased with increasing nitrogen contents. Heterojunction diodes with p-type Si were fabricated and evaluated based on current–voltage (I–V) and capacitance–voltage (C–V) characteristics measured in dark at room temperature.

Keywords: heterojunction diodes, hopping conduction mechanism, nitrogen-doping, ultra-nanocrystalline diamond

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11233 Semi-Automated Tracking of Vibrissal Movements in Free-Moving Rodents Captured by High-Speed Videos

Authors: Hyun June Kim, Tailong Shi, Seden Akdagli, Sam Most, Yuling Yan

Abstract:

Quantitative analysis of mouse whisker movement can be used to study functional recovery and regeneration of facial nerve after an injury. However, it is challenging to accurately track mouse whisker movements, and most whisker tracking methods require manual intervention, e.g. fixing the head of the mouse during a study. Here we describe a semi-automated image processing method that is applied to high-speed video recordings of free-moving mice to track whisker movements. We first track the head movement of a mouse by delineating the lower head contour frame-by-frame to locate and determine the orientation of its head. Then, a region of interest is identified for each frame, with subsequent application of the Hough transform to track individual whisker movements on each side of the head. Our approach is used to examine the functional recovery of damaged facial nerves in mice over a course of 21 days.

Keywords: mystacial macrovibrissae, whisker tracking, head tracking, facial nerve recovery

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11232 Intrathecal: Not Intravenous Administration of Evans Blue Reduces Pain Behavior in Neuropathic Rats

Authors: Kun Hua O., Dong Woon Kim, Won Hyung Lee

Abstract:

Introduction: Neuropathic pain induced by spinal or peripheral nerve injury is highly resistant to common painkillers, nerve blocks, and other pain management approaches. Recently, several new therapeutic drug candidates have been developed to control neuropathic pain. In this study, we used the spinal nerve L5 ligation (SNL) model to investigate the ability of intrathecal or intravenous Evans blue to decrease pain behavior and to study the relationship between Evans blue and the neural structure of pain transmission. Method: Neuropathic pain (allodynia) of the left hind paw was induced by unilateral SNL in Sprague-Dawley rats(n=10) in each group. Evans blue (5, 15, 50μg/10μl) or phosphate buffer saline(PBS,10μl) was injected intrathecally at 3days post-ligation or intravenously(1mg/200 μl) 3days and 5days post-ligation . Mechanical sensitivity was assessed using Von Frey filaments at 3 days post-ligation and at 2 hours, days 1, 2, 3, 5,7 after intrathecal Evans blue injection, and on days 2, 4, 7, and 11 at 14 days after intravenous injection. In the intrathecal group, microglia and glutaminergic neurons in the dorsal horn and VNUT(vesicular nucleotide transporter) in the dorsal root ganglia were tested to evaluate co-staining with Evans blue. The experimental procedures were performed in accordance with the animal care guideline of the Korean Academy of Medical Science(Animal ethic committee of Chungnam National University Hospital: CNUH-014-A0005-1). Results: Tight ligation of the L5 spinal nerve induced allodynia in the left hind paw 3 days post-ligation. Intrathecal Evans blue most significantly(P<0.001) alleviated allodynia at 2 days after intrathecal, but not an intravenous injection. Glutaminergic neurons in the dorsal horn and VNUT in the dorsal root ganglia were co-stained with Evans blue. On the other hand, microglia in the dorsal horn were partially co-stained with Evans blue. Conclusion: We confirmed that Evans blue might have an analgesic effect through the central nervous system, not another system in neuropathic pain of the SNL animal model. These results suggest Evans blue may be a potential new drug for the treatment of chronic pain. This research was supported by the National Research Foundation of Korea (NRF-2020R1A2C100757512), funded by the Ministry of Education.

Keywords: neuropathic pain, Evas blue, intrathecal, intravenous

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11231 Assessment of Kinetic Trajectory of the Median Nerve from Wrist Ultrasound Images Using Two Dimensional Baysian Speckle Tracking Technique

Authors: Li-Kai Kuo, Shyh-Hau Wang

Abstract:

The kinetic trajectory of the median nerve (MN) in the wrist has shown to be capable of being applied to assess the carpal tunnel syndrome (CTS), and was found able to be detected by high-frequency ultrasound image via motion tracking technique. Yet, previous study may not quickly perform the measurement due to the use of a single element transducer for ultrasound image scanning. Therefore, previous system is not appropriate for being applied to clinical application. In the present study, B-mode ultrasound images of the wrist corresponding to movements of fingers from flexion to extension were acquired by clinical applicable real-time scanner. The kinetic trajectories of MN were off-line estimated utilizing two dimensional Baysian speckle tracking (TDBST) technique. The experiments were carried out from ten volunteers by ultrasound scanner at 12 MHz frequency. Results verified from phantom experiments have demonstrated that TDBST technique is able to detect the movement of MN based on signals of the past and present information and then to reduce the computational complications associated with the effect of such image quality as the resolution and contrast variations. Moreover, TDBST technique tended to be more accurate than that of the normalized cross correlation tracking (NCCT) technique used in previous study to detect movements of the MN in the wrist. In response to fingers’ flexion movement, the kinetic trajectory of the MN moved toward the ulnar-palmar direction, and then toward the radial-dorsal direction corresponding to the extensional movement. TDBST technique and the employed ultrasound image scanner have verified to be feasible to sensitively detect the kinetic trajectory and displacement of the MN. It thus could be further applied to diagnose CTS clinically and to improve the measurements to assess 3D trajectory of the MN.

Keywords: baysian speckle tracking, carpal tunnel syndrome, median nerve, motion tracking

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11230 Cucurbita pepo L. Attenuates Diabetic Neuropathy by Targeting Oxidative Stress in STZ-Nicotinamide Induced Diabetic Rats

Authors: Navpreet Kaur, Randhir Singh

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Diabetic neuropathy is one of the most common microvascular complications of diabetes mellitus which affects more than 50% of diabetic patients. The present study targeted oxidative stress mediated nerve damage in diabetic rats using a hydro-alcohol extract of Cucurbita pepo L. (Family: Cucurbitaceae) and its potential in treatment of diabetic neuropathy. Diabetes neuropathy was induced in Wistar rats by injection of streptozotocin (65 mg/kg, i.p.) 15 min after Nicotinamide (230 mg/kg, i.p.) administration. Hydro-alcohol extract of C. pepo seeds was assessed by oral administration at 100, 200 and 400 mg/kg in STZ-nicotinamide induced diabetic rats. Thermal hyperalgesia (Eddy's hot plate and tail immersion), mechanical hyperalgesia (Randall-Selitto) and tactile allodynia (Von Frey hair tests) were evaluated in all groups of streptozotocin diabetic rats to assess the extent of neuropathy. Tissue (sciatic nerve) antioxidant enzymes (SOD, CAT, GSH and LPO) levels were measured along with the formation of AGEs in serum to assess the effect of hydro-alcohol extract of C. pepo in ameliorating oxidative stress. Diabetic rats exhibited significantly decreased tail-flick latency in the tail-immersion test and decreased paw withdrawal threshold in both Randall-Selitto and von-Frey hair test. A decrease in the nociceptive threshold was accompanied by significantly increased oxidative stress in sciatic nerve of diabetic rats. Treatment with the C. pepo hydro-alcohol extract significantly attenuated all the behavioral and biochemical alterations in a dose-dependent manner. C. pepo attenuated the diabetic condition and also reversed neuropathic pain through modulation of oxidative stress and thus it may find application as a possible therapeutic agent against diabetic neuropathy.

Keywords: advanced glycation end products, antioxidant enzymes, cucurbita pepo, hyperglycemia

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11229 The Transcutaneous Auricular Vagus Nerve Stimulation in Treatment of Depression and Anxiety Disorders in Recovery Patient with Feeding and Eating Disorders

Authors: Y. Melis, E. Apicella, E. Dozio, L. Mendolicchio

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Introduction: Feeding and Eating Disorders (FED) represent the psychiatric pathology with the highest mortality rate and one of the major disorders with the highest psychiatric and clinical comorbidity. The vagus nerve represents one of the main components of the sympathetic and parasympathetic nervous system and is involved in important neurophysiological functions. In FED, there is a spectrum of symptoms which with TaVNS (Transcutaneous Auricular Vagus Nerve Stimulation) therapy, is possible to have a therapeutic efficacy. Materials and Methods: Sample subjects are composed of 15 female subjects aged > 18 ± 51. Admitted to a psychiatry community having been diagnosed according to DSM-5: anorexia nervosa (AN) (N= 9), bulimia nervosa (BN) (N= 5), binge eating disorder (BED) (N= 1). The protocol included 9 weeks of Ta-VNS stimulation at a frequency of 1.5-3.5 mA for 4 hours per day. The variables detected are the following: Heart Rate Variability (HRV), Hamilton Depression Rating Scale (HAMD-HDRS-17), Body Mass Index (BMI), Beck Anxiety Index (BAI). Results: Data analysis showed statistically significant differences between recording times (p > 0.05) in HAM-D (t0 = 18.28 ± 5.31; t4 = 9.14 ± 7.15), in BAI (t0 = 24.7 ± 10.99; t4 = 13.8 ± 7.0). The reported values show how during (T0-T4) the treatment there is a decay of the degree in the depressive state, in the state of anxiety, and an improvement in the value of BMI. In particular, the BMI in the AN-BN sub-sample had a minimum gain of 5% and a maximum of 11%. The analysis of HRV did not show a clear change among subjects, thus confirming the discordance of the activity of the sympathetic and parasympathetic nervous system in FED. Conclusions: Although the sample does not possess a relevant value to determine long-term efficacy of Ta-VNS or on a larger population, this study reports how the application of neuro-stimulation in FED may become a further approach therapeutic. Indeed, substantial improvements are highlighted in the results and confirmed hypotheses proposed by the study.

Keywords: feeding and eating disorders, neurostimulation, anxiety disorders, depression

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