bluuebunny/crossref_metadata_2025_split huggingface dataset:
A computational fluid dynamics simulation framework for ventricular catheter design optimization
Authors: Weisenberg Sofy H. , TerMaath Stephanie C. , Barbier Charlotte N. , Hill Judith C. , Killeffer James A. 
Published: November 2017

OBJECTIVECerebrospinal fluid (CSF) shunts are the primary treatment for patients suffering from hydrocephalus. While proven effective in symptom relief, these shunt systems are plagued by high failure rates and often require repeated revision surgeries to replace malfunctioning components. One of the leading causes of CSF shunt failure is obstruction of the ventricular catheter by aggregations of cells, proteins, blood clots, or fronds of choroid plexus that occlude the catheter’s small inlet holes or even the full internal catheter lumen. Such obstructions can disrupt CSF diversion out of the ventricular system or impede it entirely. Previous studies have suggested that altering the catheter’s fluid dynamics may help to reduce the likelihood of complete ventricular catheter failure caused by obstruction. However, systematic correlation between a ventricular catheter’s design parameters and its performance, specifically its likelihood to become occluded, still remains unknown. Therefore, an automated, open-source computational fluid dynamics (CFD) simulation framework was developed for use in the medical community to determine optimized ventricular catheter designs and to rapidly explore parameter influence for a given flow objective.METHODSThe computational framework was developed by coupling a 3D CFD solver and an iterative optimization algorithm and was implemented in a high-performance computing environment. The capabilities of the framework were demonstrated by computing an optimized ventricular catheter design that provides uniform flow rates through the catheter’s inlet holes, a common design objective in the literature. The baseline computational model was validated using 3D nuclear imaging to provide flow velocities at the inlet holes and through the catheter.RESULTSThe optimized catheter design achieved through use of the automated simulation framework improved significantly on previous attempts to reach a uniform inlet flow rate distribution using the standard catheter hole configuration as a baseline. While the standard ventricular catheter design featuring uniform inlet hole diameters and hole spacing has a standard deviation of 14.27% for the inlet flow rates, the optimized design has a standard deviation of 0.30%.CONCLUSIONSThis customizable framework, paired with high-performance computing, provides a rapid method of design testing to solve complex flow problems. While a relatively simplified ventricular catheter model was used to demonstrate the framework, the computational approach is applicable to any baseline catheter model, and it is easily adapted to optimize catheters for the unique needs of different patients as well as for other fluid-based medical devices.
Resection of gliomas deemed inoperable by neurosurgeons based on preoperative imaging studies
Authors: Southwell Derek G. , Birk Harjus S. , Han Seunggu J. , Li Jing , Sall Jeffrey W. , Berger Mitchel S. 
Published: November 2017

OBJECTIVEMaximal safe resection is a primary objective in the management of gliomas. Despite this objective, surgeons and referring physicians may, on the basis of radiological studies alone, assume a glioma to be unresectable. Because imaging studies, including functional MRI, may not localize brain functions (such as language) with high fidelity, this simplistic approach may exclude some patients from what could be a safe resection. Intraoperative direct electrical stimulation (DES) allows for the accurate localization of functional areas, thereby enabling maximal resection of tumors, including those that may appear inoperable based solely on radiological studies. In this paper the authors describe the extent of resection (EOR) and functional outcomes following resections of tumors deemed inoperable by referring physicians and neurosurgeons.METHODSThe authors retrospectively examined the cases of 58 adult patients who underwent glioma resection within 6 months of undergoing a brain biopsy of the same lesion at an outside hospital. All patients exhibited unifocal supratentorial disease and preoperative Karnofsky Performance Scale scores ≥ 70. The EOR and 6-month functional outcomes for this population were characterized.RESULTSIntraoperative DES mapping was performed on 96.6% (56 of 58) of patients. Nearly half of the patients (46.6%, 27 of 58) underwent an awake surgical procedure with DES. Overall, the mean EOR was 87.6% ± 13.6% (range 39.0%–100%). Gross-total resection (resection of more than 99% of the preoperative tumor volume) was achieved in 29.3% (17 of 58) of patients. Subtotal resection (95%–99% resection) and partial resection (PR; < 95% resection) were achieved in 12.1% (7 of 58) and 58.6% (34 of 58) of patients, respectively. Of the cases that involved PR, the mean EOR was 79.4% ± 12.2%. Six months after surgery, no patient was found to have a new postoperative neurological deficit. The majority of patients (89.7%, 52 of 58) were free of neurological deficits both pre- and postoperatively. The remainder of patients exhibited either residual but stable deficits (5.2%, 3 of 58) or complete correction of preoperative deficits (5.2%, 3 of 58).CONCLUSIONSThe use of DES enabled maximal safe resections of gliomas deemed inoperable by referring neurosurgeons. With rare exceptions, tumor resectability cannot be determined solely by radiological studies.
Association between baseline cognitive impairment and postoperative delirium in elderly patients undergoing surgery for adult spinal deformity
Authors: Adogwa Owoicho , Elsamadicy Aladine A. , Vuong Victoria D. , Fialkoff Jared , Cheng Joseph , Karikari Isaac O. , Bagley Carlos A. 
Published: November 2017

OBJECTIVEPostoperative delirium is common in elderly patients undergoing spine surgery and is associated with a longer and more costly hospital course, functional decline, postoperative institutionalization, and higher likelihood of death within 6 months of discharge. Preoperative cognitive impairment may be a risk factor for the development of postoperative delirium. The aim of this study was to investigate the relationship between baseline cognitive impairment and postoperative delirium in geriatric patients undergoing surgery for degenerative scoliosis.METHODSElderly patients 65 years and older undergoing a planned elective spinal surgery for correction of adult degenerative scoliosis were enrolled in this study. Preoperative cognition was assessed using the validated Saint Louis University Mental Status (SLUMS) examination. SLUMS comprises 11 questions, with a maximum score of 30 points. Mild cognitive impairment was defined as a SLUMS score between 21 and 26 points, while severe cognitive impairment was defined as a SLUMS score of ≤ 20 points. Normal cognition was defined as a SLUMS score of ≥ 27 points. Delirium was assessed daily using the Confusion Assessment Method (CAM) and rated as absent or present on the basis of CAM. The incidence of delirium was compared in patients with and without baseline cognitive impairment.RESULTSTwenty-two patients (18%) developed delirium postoperatively. Baseline demographics, including age, sex, comorbidities, and perioperative variables, were similar in patients with and without delirium. The length of in-hospital stay (mean 5.33 days vs 5.48 days) and 30-day hospital readmission rates (12.28% vs 12%) were similar between patients with and without delirium, respectively. Patients with preoperative cognitive impairment (i.e., a lower SLUMS score) had a higher incidence of postoperative delirium. One- and 2-year patient reported outcomes scores were similar in patients with and without delirium.CONCLUSIONSCognitive impairment is a risk factor for the development of postoperative delirium. Postoperative delirium may be associated with decreased preoperative cognitive reserve. Cognitive impairment assessments should be considered in the preoperative evaluations of elderly patients prior to surgery.
Graft subsidence as a predictor of revision surgery following stand-alone lateral lumbar interbody fusion
Authors: Tempel Zachary J. , McDowell Michael M. , Panczykowski David M. , Gandhoke Gurpreet S. , Hamilton D. Kojo , Okonkwo David O. , Kanter Adam S. 
Published: November 2017

OBJECTIVELateral lumbar interbody fusion (LLIF) is a less invasive surgical option commonly used for a variety of spinal conditions, including in high-risk patient populations. LLIF is often performed as a stand-alone procedure, and may be complicated by graft subsidence, the clinical ramifications of which remain unclear. The aim of this study was to characterize further the sequelae of graft subsidence following stand-alone LLIF.METHODSA retrospective review of prospectively collected data was conducted on consecutive patients who underwent stand-alone LLIF between July 2008 and June 2015; 297 patients (623 levels) met inclusion criteria. Imaging studies were examined to grade graft subsidence according to Marchi criteria, and compared between those who required revision surgery and those who did not. Additional variables recorded included levels fused, DEXA (dual-energy x-ray absorptiometry) T-score, body mass index, and routine demographic information. The data were analyzed using the Student t-test, chi-square analysis, and logistic regression analysis to identify potential confounding factors.RESULTSOf 297 patients, 34 (11.4%) had radiographic evidence of subsidence and 18 (6.1%) required revision surgery. The median subsidence grade for patients requiring revision surgery was 2.5, compared with 1 for those who did not. Chi-square analysis revealed a significantly higher incidence of revision surgery in patients with high-grade subsidence compared with those with low-grade subsidence. Seven of 18 patients (38.9%) requiring revision surgery suffered a vertebral body fracture. High-grade subsidence was a significant predictor of the need for revision surgery (p < 0.05; OR 12, 95% CI 1.29–13.6), whereas age, body mass index, T-score, and number of levels fused were not. This relationship remained significant despite adjustment for the other variables (OR 14.4; 95% CI 1.30–15.9).CONCLUSIONSIn this series, more than half of the patients who developed graft subsidence following stand-alone LLIF required revision surgery. When evaluating patients for LLIF, supplemental instrumentation should be considered during the index surgery in patients with a significant risk of graft subsidence.
Long-term outcomes after surgical treatment of pediatric neurogenic thoracic outlet syndrome
Authors: Hong Jennifer , Pisapia Jared M. , Ali Zarina S. , Heuer Austin J. , Alexander Erin , Heuer Gregory G. , Zager Eric L. 
Published: November 2017

OBJECTIVENeurogenic thoracic outlet syndrome (nTOS) is an uncommon compression syndrome of the brachial plexus that presents with pain, sensory changes, and motor weakness in the affected limb. The authors reviewed the clinical presentations and outcomes in their series of pediatric patients with surgically treated nTOS over a 6-year period.METHODSCases of nTOS in patients age 18 years or younger were extracted for analysis from a prospective database of peripheral nerve operations. Baseline patient characteristics, imaging and neurophysiological data, operative findings, and outcomes and complications were assessed.RESULTSTwelve patients with 14 cases of nTOS surgically treated between April 2010 and December 2016 were identified. One-third of the patients were male, and 2 male patients underwent staged, bilateral procedures. Disabling pain (both local and radiating) was the most common presenting symptom (100%), followed by numbness (35.7%), then tingling (28.6%). The mean duration of symptoms prior to surgery was 15.8 ± 6.6 months (mean ± SD). Sports-related onset of symptoms was seen in 78.6% of cases. Imaging revealed cervical ribs in 4 cases, prominent C-7 transverse processes in 4 cases, abnormal first thoracic ribs in 2 cases, and absence of bony anomalies in 4 cases. Neurophysiological testing results were normal in 85.7% of cases. Conservative management failed in all patients, with 5 patients reporting minimal improvement in symptoms with physical therapy. With a mean follow-up after surgery of 22 ± 18.3 months (mean ± SD), pain relief was excellent (> 90%) in 8 cases (57.1%), and good (improved > 50%) in 6 cases (42.9%). On univariate analysis, patients who reported excellent pain resolution following surgery at long-term follow-up were found to be significantly younger, and to have suffered a shorter duration of preoperative symptoms than patients who had worse outcomes. Lack of significant trauma or previous surgery to the affected arm was also associated with excellent outcomes. There were 4 minor complications in 3 patients within 30 days of surgery: 1 patient developed a small pneumothorax that resolved spontaneously; 1 patient suffered a transient increase in pain requiring consultation, followed by hiccups for a period of 3 hours that resolved spontaneously; and 1 patient fell at home, with transient increased pain in the surgically treated extremity. There were no new neurological deficits, wound infections, deep vein thromboses, or readmissions.CONCLUSIONPediatric nTOS commonly presents with disabling pain and is more frequently associated with bony anomalies compared with adult nTOS. In carefully selected patients, surgical decompression of the brachial plexus results in excellent pain relief, which is more likely to be seen in younger patients who present for early surgical evaluation.
Clinical Outcomes in Duchenne Muscular Dystrophy: A Study of 5345 Patients from the TREAT-NMD DMD Global Database
Authors: Koeks Zaïda , Bladen Catherine L. , Salgado David , van Zwet Erik , Pogoryelova Oksana , McMacken Grace , Monges Soledad , Foncuberta Maria E. , Kekou Kyriaki , Kosma Konstantina , Dawkins Hugh , Lamont Leanne , Bellgard Matthew I. , Roy Anna J. , Chamova Teodora , Guergueltcheva Velina , Chan Sophelia , Korngut Lawrence , Campbell Craig , Dai Yi , Wang Jen , Barišić Nina , Brabec Petr , Lähdetie Jaana , Walter Maggie C. , Schreiber-Katz Olivia , Karcagi Veronika , Garami Marta , Herczegfalvi Agnes , Viswanathan Venkatarman , Bayat Farhad , Buccella Filippo , Ferlini Alessandra , Kimura En , van den Bergen Janneke C. , Rodrigues Miriam , Roxburgh Richard , Lusakowska Anna , Kostera-Pruszczyk Anna , Santos Rosário , Neagu Elena , Artemieva Svetlana , Rasic Vedrana Milic , Vojinovic Dina , Posada Manuel , Bloetzer Clemens , Klein Andrea , Díaz-Manera Jordi , Gallardo Eduard , Karaduman A. Ayşe , Oznur Tunca , Topaloğlu Haluk , El Sherif Rasha , Stringer Angela , Shatillo Andriy V. , Martin Ann S. , Peay Holly L. , Kirschner Jan , Flanigan Kevin M. , Straub Volker , Bushby Kate , Béroud Christophe , Verschuuren Jan J. , Lochmüller Hanns 
Published: November 2017

Background: Recent short-term clinical trials in patients with Duchenne Muscular Dystrophy (DMD) have indicated greater disease variability in terms of progression than expected. In addition, as average life-expectancy increases, reliable data is required on clinical progression in the older DMD population. Objective: To determine the effects of corticosteroids on major clinical outcomes of DMD in a large multinational cohort of genetically confirmed DMD patients. Methods: In this cross-sectional study we analysed clinical data from 5345 genetically confirmed DMD patients from 31 countries held within the TREAT-NMD global DMD database. For analysis patients were categorised by corticosteroid background and further stratified by age. Results: Loss of ambulation in non-steroid treated patients was 10 years and in corticosteroid treated patients 13 years old ( p = 0.0001). Corticosteroid treated patients were less likely to need scoliosis surgery ( p < 0.001) or ventilatory support ( p < 0.001) and there was a mild cardioprotective effect of corticosteroids in the patient population aged 20 years and older ( p = 0.0035). Patients with a single deletion of exon 45 showed an increased survival in contrast to other single exon deletions. Conclusions: This study provides data on clinical outcomes of DMD across many healthcare settings and including a sizeable cohort of older patients. Our data confirm the benefits of corticosteroid treatment on ambulation, need for scoliosis surgery, ventilation and, to a lesser extent, cardiomyopathy. This study underlines the importance of data collection via patient registries and the critical role of multi-centre collaboration in the rare disease field.
Assessment of anti-arthritic potential of Ephedra gerardiana by in vitro and in vivo methods
Authors: Uttra Ambreen Malik , . Alamgeer 
Published: November 2017

<p class="Abstract">The present study determines the anti-arthritic potential of Ephedra gerardiana ethanolic extract and its ethyl acetate, n-butanol and aqueous fractions adopting in vitro and in vivo tests. In vitro tests included thermally induced bovine serum albumin denaturation and egg albumin denaturation, also membrane stabilizing assay at concentration of 50-6400 µg/mL, whereas in vivo study comprised formaldehyde-induced arthritis at 50, 100 and 200 mg/kg doses. The crude extract and fractions inhibited protein denaturation and stabilized red blood cells membrane in concentration-dependent fashion, with maximal effect achieved at 6,400 µg/mL (p&lt;0.001). Similarly, in formaldehyde model, the extract and fractions dose-dependently reduced injected paw volume and diameter, with maximum reduction at 200 mg/kg (p&lt;0.001). However, results of aqueous fraction were on a par with hydroalcoholic extract in each test. These results suggest that E. gerardiana provides protection against arthritis that might be owing to the existence of phytoconstituents thus, supporting folkloric claim.</p><p><strong>Video Clip of Methodology</strong>:</p><p>23 min 48 sec: <a href="https://youtube.com/v/Pr4sgq3sBUY">Full Screen</a> <a href="https://youtube.com/watch?v=Pr4sgq3sBUY">Alternate</a></p>
On Shocks Driven by High-mass Planets in Radiatively Inefficient Disks. III. Observational Signatures in Thermal Emission and Scattered Light
Authors: Hord Blake , Lyra Wladimir , Flock Mario , Turner Neal J. , Mac Low Mordecai-Mark 
Published: November 2017

Abstract
Recent observations of the protoplanetary disk around the Herbig Be star HD 100546 show two bright features in infrared (H and

bands) at about 50 au,with one so far unexplained. We explore the observational signatures of a high-mass planet causing shock heating in order to determine if it could be the source of the unexplained infrared feature in HD 100546. More fundamentally, we identify and characterize planetary shocks as an extra, hitherto ignored, source of luminosity in transition disks. The RADMC-3D code is used to perform dust radiative transfer calculations on the hydrodynamical disk models, including volumetric heating. A stronger shock heating rate by a factor of 20 would be necessary to qualitatively reproduce the morphology of the second infrared source. Instead, we find that the outer edge of the gap carved by the planet heats up by about 50% relative to the initial reference temperature, which leads to an increase in the scale height. The bulge is illuminated by the central star, producing a lopsided feature in scattered light, as the outer gap edge shows an asymmetry in density and temperature attributable to a secondary spiral arm launched not from the Lindblad resonances but from the 2:1 resonance. We conclude that high-mass planets lead to shocks in disks that may be directly observed, particularly at wavelengths of 10 μm or longer, but that they are more likely to reveal their presence in scattered light by puffing up their outer gap edges and exciting multiple spiral arms.
Associating Fast Radio Bursts with Their Host Galaxies
Authors: Eftekhari T. , Berger E. 
Published: November 2017

Abstract
The first precise localization of a fast radio burst (FRB) sheds light on the nature of these mysterious bursts and the physical mechanisms that power them. Increasing the sample of FRBs with robust host galaxy associations is the key impetus behind ongoing and upcoming searches and facilities. Here, we quantify the robustness of FRB host galaxy associations as a function of localization area and galaxy apparent magnitude. We also explore the use of FRB dispersion measures to constrain the source redshift, thereby reducing the number of candidate hosts. We use these results to demonstrate that even in the absence of a unique association, a constraint can be placed on the maximum luminosity of a host galaxy as a function of localization and dispersion measure (DM). We find that localizations of

are required for a chance coincidence probability of

for dwarf galaxies at

if some hosts have luminosities of

, then localizations of up to

may suffice at

. Constraints on the redshift from the DM only marginally improve the association probability unless the DM is low,

pc cm−3. This approach also relies on the determination of galaxy redshifts, which is challenging at

if the hosts are dwarf galaxies. Finally, interesting limits on the maximum host luminosity require localizations of

at

. Even a few such localizations will explain the nature of FRB progenitors, their possible diversity, and their use as cosmological tools.
The VLBA Extragalactic Proper Motion Catalog and a Measurement of the Secular Aberration Drift
Authors: Truebenbach Alexandra E. , Darling Jeremy 
Published: November 2017

Abstract
We present a catalog of extragalactic proper motions created using archival VLBI data and our own VLBA astrometry. The catalog contains 713 proper motions, with average uncertainties of ∼24 μas yr−1, including 40 new or improved proper motion measurements using relative astrometry with the VLBA. The observations were conducted in the X-band and yielded positions with uncertainties of ∼70 μas. We add 10 new redshifts using spectroscopic observations taken at Apache Point Observatory and Gemini North. With the VLBA Extragalactic Proper Motion Catalog, we detect the secular aberration drift—the apparent motion of extragalactic objects caused by the solar system’s acceleration around the Galactic center—at a 6.3σ significance. We model the aberration drift as a spheroidal dipole, with the square root of the power equal to 4.89 ± 0.77 μas yr−1, an amplitude of 1.69 ± 0.27 μas yr−1, and an apex at (

,

). Our dipole model detects the aberration drift at a higher significance than some previous studies, but at a lower amplitude than expected or previously measured. The full aberration drift may be partially removed by the no-net-rotation constraint used when measuring archival extragalactic radio source positions. Like the cosmic microwave background dipole, which is induced by the observer’s motion, the aberration drift signal should be subtracted from extragalactic proper motions in order to detect cosmological proper motions, including the Hubble expansion, long-period stochastic gravitational waves, and the collapse of large-scale structure.