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1.
Indian J Pathol Microbiol ; 66(2): 339-342, 2023.
Article in English | MEDLINE | ID: mdl-37077078

ABSTRACT

Introduction: Covid 19 pandemic has brought human life one on one with the pace of growth. The indispensable lockdown and social distancing norms have posed challenges to continue education in various fields. Distance learning via online teaching has emerged as a savior in the pandemic. In the current scenario, it is very important to keep learners in the loop and obtain feedback from students at the end of online teaching, for understanding its strength and weaknesses which will eventually assist in developing strategies to improve its quality. We intend to share our experience with the online teaching. Materials and Methods: The study was conducted from March 2020 to Feb 2021, which includes 8 months of online teaching classes and practicals, one online examination (mid term exam), and 1 offline examination (final professional exam). The marks obtained by the students who attended online classes (batch II) in 2020-21 session was compared with previous batch i.e 2019-20 (batch I). Also the marks obtained by batch I during online exam (mid-term exam) were compared with their marks during offline exam (final professional exam). Results: Batch II scored higher marks than batch I in theory and practical (p-value < 0.05). However, the marks of viva for both batches were equitable. Conclusions: We feel that the online teaching is a reasonable alternative to conventional teaching in the current scenario.


Subject(s)
COVID-19 , Education, Distance , Humans , Pandemics/prevention & control , Communicable Disease Control , Students
2.
J Mol Model ; 28(11): 373, 2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36322186

ABSTRACT

Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations are used to investigate the effect of methoxy and anisyl molecules attached to perylene, as well as the different positions of the sensitizers' π-spacers. The optical, spectroscopic, and electrochemical properties of designed sensitizers are investigated in dye-sensitized solar cell (DSSC) applications. Perylene serves as an electron donor and cyanoacrylic acid serves as an acceptor in the sensitizers under investigation. In the six configurations designed, cyanovinyl and thiophene are used as π-spacers. Methoxy and anisyl groups are two more donors that were combined with perylene to study the sensitizers' optoelectronic properties. UV-vis absorption spectra, light-harvesting efficiency (LHE), highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy gap, electron injection, electron regeneration, and nonlinear optical properties were used to compare optical and electronic properties. The incorporation of additional donors and different positions of spacers reduced the energy gap; red shifted the absorption spectra; and are prone to exhibit better power conversion efficiency (PCE) of the DSSC.

3.
Oper Neurosurg (Hagerstown) ; 20(6): 549-558, 2021 05 13.
Article in English | MEDLINE | ID: mdl-33571367

ABSTRACT

BACKGROUND: The reverse question mark (RQM) incision has been traditionally utilized to perform decompressive hemicraniectomies (DHC) to relieve refractory intracranial hypertension. Alternative incisions have been proposed in the literature but have not been compared directly. OBJECTIVE: To present the retroauricular (RA) incision as an alternative incision that we hypothesize will increase calvarium exposure to maximize the removal of the hemicranium and will decrease wound-related complications compared to the RQM incision. METHODS: This study is a retrospective review of all DHCs performed at our institution over a span of 34 mo, stratified based on the type of scalp incision. The surface areas of the cranial defects were calculated, normalizing to their respective skull diameters. For those patients surviving beyond 1 wk, complications were examined from both cohorts. RESULTS: A total of 63 patients in the RQM group and 43 patients in the RA group were included. The average surface area for the RA and RQM incisions was 117.0 and 107.8 cm2 (P = .0009), respectively. The ratio of average defect size to skull size for RA incision was 0.81 compared to 0.77 for the RQM group (P = .0163). Of those who survived beyond 1 wk, the absolute risk for surgical site complications was 14.0% and 8.3% for RQM and RA group (P = .5201), respectively. CONCLUSION: The RA incision provides a safe and effective alternative incision to the traditional RQM incision used for DHC. This incision affords a potentially larger craniectomy while mitigating postoperative wound complications.


Subject(s)
Intracranial Hypertension , Skull , Craniotomy , Humans , Intracranial Hypertension/etiology , Intracranial Hypertension/surgery , Retrospective Studies , Skull/surgery , Treatment Outcome
4.
World Neurosurg ; 146: e1191-e1201, 2021 02.
Article in English | MEDLINE | ID: mdl-33271378

ABSTRACT

OBJECTIVE: Coronavirus disease 2019 (COVID-19) continues to affect all aspects of health care delivery, and neurosurgical practices are not immune to its impact. We aimed to evaluate neurosurgical practice patterns as well as the perioperative incidence of COVID-19 in neurosurgical patients and their outcomes. METHODS: A retrospective review of neurosurgical and neurointerventional cases at 2 tertiary centers during the first 3 months of the first peak of COVID-19 pandemic (March 8 to June 8) as well as following 3 months (post-peak pandemic; June 9 to September 9) was performed. Baseline characteristics, perioperative COVID-19 test results, modified Medically Necessary, Time-Sensitive (mMeNTS) score, and outcome measures were compared between COVID-19-positive and-negative patients through bivariate and multivariate analysis. RESULTS: In total, 652 neurosurgical and 217 neurointerventional cases were performed during post-peak pandemic period. Cervical spine, lumbar spine, functional/pain, cranioplasty, and cerebral angiogram cases were significantly increased in the postpandemic period. There was a 2.9% (35/1197) positivity rate for COVID-19 testing overall and 3.6% (13/363) positivity rate postoperatively. Age, mMeNTS score, complications, length of stay, case acuity, American Society of Anesthesiologists status, and disposition were significantly different between COVID-19-positive and-negative patients. CONCLUSIONS: A significant increase in elective case volume during the post-peak pandemic period is feasible with low and acceptable incidence of COVID-19 in neurosurgical patients. COVID-19-positive patients were younger, less likely to undergo elective procedures, had increased length of stay, had more complications, and were discharged to a location other than home. The mMeNTS score plays a role in decision-making for scheduling elective cases.


Subject(s)
COVID-19/epidemiology , COVID-19/prevention & control , Neurosurgical Procedures/trends , Perioperative Care/trends , Tertiary Care Centers/trends , Adult , Aged , COVID-19/diagnosis , District of Columbia/epidemiology , Female , Follow-Up Studies , Humans , Incidence , Male , Middle Aged , Neurosurgical Procedures/methods , Pandemics/prevention & control , Perioperative Care/methods , Retrospective Studies , Time Factors , Treatment Outcome
5.
Brain Imaging Behav ; 15(2): 941-957, 2021 Apr.
Article in English | MEDLINE | ID: mdl-32710332

ABSTRACT

Post-traumatic stress disorder (PTSD) manifests as emotional suffering and problem-solving impairments under extreme stress. This meta-analysis aimed to pool the findings from all the studies examining emotion and cognition in individuals with PTSD to develop a robust mechanistic understanding of the related brain dysfunction. We identified primary studies through a comprehensive literature search of the MEDLINE and PsychINFO databases. The GingerALE software (version 2.3.6) from the BrainMap Project was used to conduct activation likelihood estimation meta-analyses of the eligible studies for cognition, emotion and interface of both. Relative to the non-clinical (NC) group, the PTSD group showed greater activation during emotional tasks in the amygdala and parahippocampal gyrus. In contrast, the NC group showed significantly greater activation in the bilateral anterior cingulate cortex (ACC) than did the PTSD group in the emotional tasks. When both emotional and cognitive processing were evaluated, the PTSD group showed significantly greater activation in the striatum than did the NC group. No differences in activation between the PTSD and NC groups were noted when only the cognitive systems were examined. Individuals with PTSD exhibited overactivity in the subcortical regions, i.e., amygdala and striatum, when processing emotions. Underactivity in the emotional and cognitive processing intermediary cortex, i.e., the ACC, was especially prominent in individuals with PTSD relative to the NC population following exposure to emotional stimuli. These findings may explain the trauma-related fear, irritability, and negative effects as well as the concentration difficulties during cognitive distress associated with emotional arousal, that are commonly observed in individuals with PTSD.


Subject(s)
Stress Disorders, Post-Traumatic , Amygdala/diagnostic imaging , Cognition , Emotions , Humans , Magnetic Resonance Imaging , Stress Disorders, Post-Traumatic/diagnostic imaging
7.
Clin Neurol Neurosurg ; 199: 106263, 2020 12.
Article in English | MEDLINE | ID: mdl-33059316

ABSTRACT

BACKGROUND: Ventriculoperitoneal shunts (VPS) are placed for a variety of etiologies. It is common for general surgery to assist with insertion of the distal portion in the peritoneum. OBJECTIVE: To determine if there is a difference in revision rates in patients undergoing VPS placement with general surgery as well as those undergoing laparoscopic insertion. METHODS: A retrospective review of all consecutive patients undergoing VPS placements was performed in a three-year period (2017-2019). Those that underwent placement with general surgery were compared to those without general surgery. Additionally, patients undergoing distal placement via mini-laparotomy versus laparoscopy were compared. Multivariable logistic regression was used to examine risk factors for distal VPS failure. RESULTS: 331 patients were included. 202 (61.0 %) underwent VPS placement with general surgery. 121 (36.6 %) patients underwent insertion via laparoscopic technique. General surgery involvement reduced operative times, decreased length of stay, and lowered overall revision rates with distal revision rates being most significant (1.5 % vs 8.5 %; p = 0.0034). Patients undergoing VPS placement via laparoscopic technique had decreased operative time, length of stay, in-hospital complications and revision rates, with significant decrease in shunt infection (1.7 % vs 7.1 %; p = 0.0366). A history of prior shunt or abdominal surgery (OR 3.826; p = 0.0282) and lack of general surgery involvement (OR 20.98; p = 0.0314) are independent risk factors for distal shunt revision in our cohort. CONCLUSION: The use of general surgeons in VPS insertion can be of benefit by decreasing operative time, length of stay, total revisions, and distal revision rates. Further prospective studies are warranted to determine true benefit.


Subject(s)
Laparoscopy/trends , Laparotomy/trends , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Reoperation/trends , Ventriculoperitoneal Shunt/trends , Adult , Aged , Cohort Studies , Female , Humans , Laparoscopy/adverse effects , Laparoscopy/methods , Laparotomy/adverse effects , Laparotomy/methods , Male , Middle Aged , Operative Time , Postoperative Complications/diagnosis , Reoperation/methods , Retrospective Studies , Surgical Procedures, Operative/adverse effects , Surgical Procedures, Operative/methods , Surgical Procedures, Operative/trends , Ventriculoperitoneal Shunt/adverse effects , Ventriculoperitoneal Shunt/methods , Young Adult
8.
World Neurosurg ; 143: e550-e560, 2020 11.
Article in English | MEDLINE | ID: mdl-32777390

ABSTRACT

OBJECTIVE: The true incidence of perioperative coronavirus disease 2019 (COVID-19) has not been well elucidated in neurosurgical studies. We reviewed the effects of the pandemic on the neurosurgical case volume to study the incidence of COVID-19 in patients undergoing these procedures during the perioperative period and compared the characteristics and outcomes of this group to those of patients without COVID-19. METHODS: The neurosurgical and neurointerventional procedures at 2 tertiary care centers during the pandemic were reviewed. The case volume, type, and acuity were compared to those during the same period in 2019. The perioperative COVID-19 tests and results were evaluated to obtain the incidence. The baseline characteristics, including a modified Medically Necessary Time Sensitive (mMeNTS) score, and outcome measures were compared between those with and without COVID-19. RESULTS: A total of 405 cases were reviewed, and a significant decrease was found in total spine, cervical spine, lumbar spine, and functional/pain cases. No significant differences were found in the number of cranial or neurointerventional cases. Of the 334 patients tested, 18 (5.4%) had tested positive for COVID-19. Five of these patients were diagnosed postoperatively. The mMeNTS score, complications, and case acuity were significantly different between the patients with and without COVID-19. CONCLUSION: A small, but real, risk exists of perioperative COVID-19 in neurosurgical patients, and those patients have tended to have a greater complication rate. Use of the mMeNTS score might play a role in decision making for scheduling elective cases. Further studies are warranted to develop risk stratification and validate the incidence.


Subject(s)
COVID-19/virology , Elective Surgical Procedures/statistics & numerical data , Neurosurgery/statistics & numerical data , SARS-CoV-2/pathogenicity , Adult , District of Columbia , Female , Humans , Incidence , Male , Neurosurgical Procedures/statistics & numerical data , Tertiary Care Centers , Young Adult
9.
Abdom Radiol (NY) ; 45(4): 1193-1197, 2020 04.
Article in English | MEDLINE | ID: mdl-32088778

ABSTRACT

PURPOSE: To report outcomes of percutaneous cholecystostomy (PC) catheter placement in patients with acute cholecystitis (AC) and propose management algorithm of AC after PC catheter placement based on the outcomes. METHOD AND MATERIALS: Retrospective study was performed. 419 patients who underwent PC between July 2010 and September 2016 were included. Patients who underwent PC for indication other than AC were excluded. The primary outcome was definitive treatment of AC following PC, including cholecystectomy or percutaneous cholecystolithotomy. Secondary outcomes include removal of drainage catheter without further management or death with catheter in place. Based on outcomes, we proposed management algorithm of AC after PC catheter placement. RESULTS: 377 of 419 patients underwent PC for treatment of AC (median age, 66 years; range 18-100 years). Technical success rate was 100% with 2.4% major complications rate and 1.6% minor complications rate. Following PC, 118 patients (31%) underwent definitive treatment with cholecystectomy. Sixty-one patients (16%) underwent definitive treatment with percutaneous cholecystolithotomy with removal of catheters. Seventy-four patients (20%) had their catheters removed upon resolution of cholecystitis without undergoing surgery or stone removal. Fifty patients (13%) died with catheters in place due to other comorbidities. Five patients (1%) still had their catheters in place at the end of the study. CONCLUSION: PC remains a viable option for treatment of AC with low complication rate and can be used as bridge to definitive therapy. Our proposed management algorithm can be a guideline for the management of AC after PC catheter placement.


Subject(s)
Algorithms , Cholecystitis, Acute/therapy , Cholecystostomy/methods , Postoperative Complications/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Catheters, Indwelling , Cholangiography , Cholecystitis, Acute/diagnostic imaging , Contrast Media , Female , Humans , Male , Middle Aged , Postoperative Complications/diagnostic imaging , Retrospective Studies
10.
Psychiatry Res Neuroimaging ; 288: 37-43, 2019 06 30.
Article in English | MEDLINE | ID: mdl-31071543

ABSTRACT

Adolescence is a vulnerable period for major depressive disorder (MDD). The aim of our study was to investigate resting-state functional connectivity (RSFC) in first-episode, medication-naïve adolescent MDD patients. Twenty-three drug-naïve adolescents diagnosed with first-episode MDD and 27 healthy participants were enrolled. Seed-to-voxel RSFC analyses were performed. The frontolimbic circuit regions of interest included the amygdala, anterior cingulate cortex, insula, and hippocampus. A correlation analysis between the RSFC and Children's Depression Inventory, Hamilton depression rating scale, and duration of episodes was performed. The adolescents with MDD exhibited the following characteristics: a lower RSFC between the right amygdala and right superior frontal gyrus; a lower RSFC between the right hippocampus and clusters including the right insula and right middle frontal gyrus; a higher RSFC between the left insula and clusters including the bilateral middle frontal gyrus, right superior frontal gyrus, and right frontal pole; and a higher RSFC between the left dorsal anterior cingulate cortex and a cluster including the left insula. Medication-naïve adolescents with depression display lower connectivity of several brain regions implicated in processing, regulation, and memory of emotions. Higher connectivity was observed in brain regions that potentially explain rumination, impaired concentration, and physiological arousal.


Subject(s)
Adolescent Behavior/psychology , Cerebral Cortex/diagnostic imaging , Depressive Disorder, Major/diagnostic imaging , Depressive Disorder, Major/psychology , Hippocampus/diagnostic imaging , Magnetic Resonance Imaging/methods , Adolescent , Case-Control Studies , Cerebral Cortex/physiopathology , Depressive Disorder, Major/physiopathology , Female , Hippocampus/physiopathology , Humans , Male , Nerve Net/diagnostic imaging , Nerve Net/physiopathology , Prospective Studies , Rest/psychology
11.
Article in English | MEDLINE | ID: mdl-29782956

ABSTRACT

OBJECTIVES: Attention deficit has been shown to exist in adult and pediatric bipolar disorder across the life span. Given that emotion dysregulation is central to bipolar disorder, this study hypothesizes that emotional circuitry regions are altered along with anomalies in the attentional systems during cognitive deployment in bipolar disorder. METHODS: An activation likelihood estimation meta-analysis of attentional activities using GingerALE software was completed for adult and pediatric bipolar disorder populations in all published studies till December 2017. The meta-analysis of all fMRI studies included a total of ten pediatric studies (comprised of pediatric bipolar disorder (PBD) and typically developing (TD) groups) and nine adult patient studies (comprised of adult bipolar disorder (ABD) and healthy control (HC) groups). RESULTS: While engaged in attentional tasks, increased activation was seen in inferior frontal gyrus with decreased activation in limbic regions in subjects with PBD, relative to TD. Differential patterns of underactivity were also noted in the dorsal attentional system i.e., frontostriatal circuit (dorsolateral prefrontal cortex, anterior cingulate cortex, right lentiform nucleus and right globus pallidus) in PBD patients relative to the TD. However, we did not see any significant differences between the adult groups i.e., ABD vs. HC. CONCLUSIONS: In PBD, deploying attentional system potentially improves the fronto-limbic affective circuitry function, despite impaired dorsal attentional system i.e., fronto-striatal circuitry. In contrast, these neural correlates underlying attentional engagement appeared to be not significant in adult BD. LIMITATIONS: We examined the PBD vs. TD and the ABD vs. HC separately instead of four-way contrast (dual meta-analytic study). Also, attentional tasks were not unidimensional and tend to capture selective and sustained attention along with response inhibition, thereby recruiting multiple brain circuits.


Subject(s)
Attention , Bipolar Disorder/diagnostic imaging , Limbic System/diagnostic imaging , Magnetic Resonance Imaging/methods , Prefrontal Cortex/diagnostic imaging , Attention/physiology , Bipolar Disorder/physiopathology , Bipolar Disorder/psychology , Child , Humans , Limbic System/physiopathology , Prefrontal Cortex/physiopathology
12.
Nat Commun ; 9(1): 3196, 2018 08 10.
Article in English | MEDLINE | ID: mdl-30097571

ABSTRACT

The biological determinants of sensitivity and resistance to immune checkpoint blockers are not completely understood. To elucidate the role of intratumoral T-cells and their association with the tumor genomic landscape, we perform paired whole exome DNA sequencing and multiplexed quantitative immunofluorescence (QIF) in pre-treatment samples from non-small cell lung carcinoma (NSCLC) patients treated with PD-1 axis blockers. QIF is used to simultaneously measure the level of CD3+ tumor infiltrating lymphocytes (TILs), in situ T-cell proliferation (Ki-67 in CD3) and effector capacity (Granzyme-B in CD3). Elevated mutational load, candidate class-I neoantigens or intratumoral CD3 signal are significantly associated with favorable response to therapy. Additionally, a "dormant" TIL signature is associated with survival benefit in patients treated with immune checkpoint blockers characterized by elevated TILs with low activation and proliferation. We further demonstrate that dormant TILs can be reinvigorated upon PD-1 blockade in a patient-derived xenograft model.


Subject(s)
Carcinoma, Non-Small-Cell Lung/immunology , Lung Neoplasms/immunology , Lymphocytes, Tumor-Infiltrating/immunology , Amino Acid Sequence , Animals , Antibodies, Blocking/pharmacology , Carcinogenesis/drug effects , Carcinogenesis/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Cell Proliferation/drug effects , Cytotoxicity, Immunologic/drug effects , Histocompatibility Antigens Class I/metabolism , Humans , Lung Neoplasms/pathology , Lymphocyte Activation/immunology , Lymphocytes, Tumor-Infiltrating/drug effects , Lymphocytes, Tumor-Infiltrating/pathology , Male , Mice, Inbred NOD , Mice, SCID , Mutant Proteins/chemistry , Mutation/genetics , Peptides/chemistry , Phenotype , Programmed Cell Death 1 Receptor/metabolism , Reproducibility of Results , Survival Analysis , Nicotiana
13.
Int J Biol Macromol ; 113: 329-337, 2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29481953

ABSTRACT

The conversion of starch to maltose is catalysed in plants by ß-amylase. The enzymatic mechanism has been well-characterized for the soybean and barley enzymes, which utilise a glutamic acid-glutamate pair. In the present study, we present a surprise observation of maltotetraose at the active site, the presence of which elucidates the clear role of Thr344 as a conformational "switch" between substrate binding and product release during hydrolysis. This observation is confirmed by the selection of maltotetraose by the crystallized enzyme although that carbohydrate was present in only trace amounts. The conformation of the residues in the substrate-binding site changed upon substrate binding, leading to the movement of threonine, glutamic acid, and the loop conformation, elucidating a missing link in the existing mechanism. By aligning our substrate-free and maltotetraose-bound structures with other existing structures, the sequence of events from substrate binding to hydrolysis can be visualized. Apart from this, the evolutionary relationship among ß-amylases of bacterial and amyloplastic origin could be established. The presence of a sugar-binding domain in the bacterial enzyme and its absence in the plant counterpart could be attributed to a carbohydrate-rich environment. Interestingly, cladogram analysis indicates the presence of N-terminal additions in some plant ß-amylases. Based on sequence similarity, we postulate that the role of such additions is important for the regulation of enzymatic activity, particularly under stress conditions.


Subject(s)
Bacteria/enzymology , Evolution, Molecular , Ipomoea batatas/enzymology , Starch/metabolism , beta-Amylase/chemistry , beta-Amylase/metabolism , Catalytic Domain , Hydrolysis , Models, Molecular , Sequence Alignment
14.
Oper Neurosurg (Hagerstown) ; 14(3): 303-311, 2018 03 01.
Article in English | MEDLINE | ID: mdl-28541569

ABSTRACT

BACKGROUND: Smartphone applications (apps) in the health care arena are being increasingly developed with the aim of benefiting both patients and their physicians. The delivery of adequate instructions both before and after a procedure or surgery is of paramount importance in ensuring the best possible outcome for patients. OBJECTIVE: To demonstrate that app-based instructions with built-in reminders may improve patient understanding and compliance and contribute to reducing the number of surgery cancellations and postoperative complications and readmissions. METHODS: We prospectively accrued 56 patients undergoing routine neurosurgery procedures who subsequently downloaded the app. The median age was 54 (range 27-79). Patients were followed for successful registration and use of the app, compliance with reading instructions before and after surgery, and sending pain scores and/or wound images. The number of surgeries cancelled, postoperative complications, 30-d readmissions, and phone calls for surgery-related questions were examined. RESULTS: Fifty-four of the 56 patients successfully registered, downloaded, and used the app and read and complied with instructions both before and after surgery. There were no cancelled surgeries. There was 1 postoperative complication. There were no readmissions. Eight of the 54 patients (14.8%) called the office on a single occasion for a surgery related question. CONCLUSION: We demonstrate the utility of a smartphone application in the perioperative neurosurgical care setting with regard to patient compliance and satisfaction as well as surgery cancellations and readmissions. Further study of a larger number of patients with a control group is warranted.


Subject(s)
Mobile Applications , Neurosurgical Procedures , Patient Compliance , Patient Satisfaction , Perioperative Care , Academic Medical Centers , Adult , Aged , Female , Humans , Male , Middle Aged , Patient Readmission
15.
Cureus ; 9(5): e1231, 2017 May 09.
Article in English | MEDLINE | ID: mdl-28620562

ABSTRACT

Injury to the thoracic duct during anterior cervical spine surgery is a rare occurrence. A delayed chyle leak following an elective anterior cervical spinal surgery has not been reported in the literature. We present a report of a 59-year-old female with multiple prior neck surgeries who underwent an anterior cervical corpectomy and fusion (ACCF). The patient developed a delayed thoracic duct injury on postoperative day (POD) one, as no injury was noted intraoperatively. She was managed with conservative care involving a low-fat diet along with octreotide which led to the resolution of her symptoms. We present this case report because of its unique presentation and to assist spine surgeons with initial management. Surgeons should have increased awareness when performing anterior cervical approaches to the lower cervical and upper thoracic levels from the left side.

16.
Carbohydr Polym ; 157: 38-47, 2017 Feb 10.
Article in English | MEDLINE | ID: mdl-27987941

ABSTRACT

Proton conducting materials create prime interest in electro chemical device development. Present work has been carried out to design environment friendly new biopolymer electrolytes (BPEs) using cellulose acetate (CA) complex with different concentrations of ammonium nitrate (NH4NO3), which have been prepared as film and characterized. The 50mol% CA and 50mol% NH4NO3 complex has highest ionic conductivity (1.02×10-3Scm-1). Differential scanning calorimetry shows the changes in glass transition temperature depends on salt concentration. Structural analysis indicates that the highest ionic conductivity complex exhibits more amorphous nature. Vibrational analysis confirms the complex formation, which has been validated theoretically by Gaussian 09 software. Conducting element in the BPEs has been predicted. Primary proton battery and proton exchange membrane fuel cell have been developed for highest ionic conductivity complex. Output voltage and power performance has been compared for single fuel cell application, which manifests the present BPE holds promise application in electrochemical devices.

19.
Cureus ; 8(7): e715, 2016 Jul 27.
Article in English | MEDLINE | ID: mdl-27610287

ABSTRACT

Mobile schwannomas of the spine have been sparsely documented in the literature. In cases referred to in existing literature, the migratory schwannoma was documented to occur in the lumbar spine. We added another case to the small available literature. In our case report, the patient had a previously known lumbar schwannoma that was being managed conservatively. Due to an acute change in clinical symptoms, repeat imaging was performed. A magnetic resonance imaging (MRI) of his spine revealed migration of the schwannoma two levels rostral to his recent imaging from six weeks earlier. The patient underwent surgical resection of his lesion. During the operation, the ultrasound was utilized to confirm the lesion prior to dural opening. In this report, we attempt to provide further evidence of the utility of an intraoperative ultrasound for intradural lesions and intend to add to the published literature of mobile schwannomas of the spine.

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