bluuebunny/crossref_metadata_2025_split huggingface dataset:
Constitutive modeling for high temperature compressive deformation of non-oriented electrical steel
Authors: Dong Qiang , Zhang Jianshui 
Published: March 2019

Abstract
A material mechanical model provides basic data for numerical simulation and technological optimization during the forming process. In this paper, the flow behavior of the hot compressive deformation 0.3 wt.-% Si non-orientation electrical steel were investigated by thermal simulation tests, and a constitutive model was built based on a new modeling method. The thermal simulation tests conducted on a Gleeble 1500 thermo-mechanical simulator over a range of temperatures from 750 to 1050 °C and strain rates from 0.1 to 10 s−1. To predict the hot deformation process of the silicon steel, a constitutive model based on the multiple regression method was developed. Prediction results showed that the proposed model can track deformational behavior accurately. The model was applied to finite element (FE) simulation, and the FE calculation results matched the industry production data satisfactorily.
Laser speckle photometry – Optical sensor systems for condition and process monitoring
Authors: Chen Lili , Cikalova Ulana , Bendjus Beatrice , Gommlich Andreas , Sudip Shohag Roy , Schott Carolin , Steingroewer Juliane , Belting Matthias , Kleszczynski Stefan 
Published: March 2019

Abstract
Laser speckle photometry (LSP) is an innovative, non-destructive monitoring technique based on the detection and analysis of thermally or mechanically activated speckle dynamics in a non-stationary optical field. With the development of speckle theories, it has been found that speckle patterns carry information about surface characteristics. Therefore, LSP offers a great potential for the characterization of material properties and monitoring of manufacturing processes. In contrast to the speckle interferometry method, LSP is very simple and robust. The sample is illuminated by only one laser beam to generate a speckle pattern on the surface. The signals obtained are directly recorded by a CCD or CMOS camera. By appropriate optical solutions for the beam path, typically, resolutions of less than 10 μm are reached if larger areas are illuminated. LSP is definitely a contactless, quick and quality relevant material characterization and defect detection method, allowing process monitoring in many industrial fields. Examples from online biotechnological monitoring and laser based manufacturing demonstrate further potentials of the method for process monitoring and controlling.
Effects of induction hardened surface depth on the dynamic behavior of rotating shaft systems
Authors: Kabasakaloglu Ufuk , Saruhan Hamit 
Published: March 2019

AbstractRotating shaft systems play many critical roles in rotating machinery. The performance of any rotating machinery is very dependent on vibrations generated by the rotating shaft. The selection of rotating shaft material is very important to meeting the enormous demand of industrial users on the capability of vibration resistance in rotating machinery. Recent requirements for using rotating shafts have heightened the need for the materials used. The heat treatment of material has received much attention over the last few decades. The research to date has tended to focus on material properties for resistance and strength rather than on dynamic behavior. The main objective of the present study is to experimentally investigate the role of induction surface hardening which is one of the most commonly used types of heat treatment on AISI 1045 steel dynamic behavior. Heat treatable AISI 1045 steel is among the most widely used in all industrial applications requiring more resistance and strength. It has received much attention over the past several decades due to its usage in rotating shafts, axles, crankshafts, and spindles. Induction surface hardening is used to sustain service life by increasing the surface hardness and vibration reliability of a material. Since induction hardened surface depth plays a very important part in the stability of the rotating shaft, three different hardened surface depths (0.5, 1.0, and 1.5 mm) are utilized. The results show that a hardened surface depth of 1.0 mm surprisingly and positively affects the dynamic behavior of the rotating shaft as compared to the hardened surface depths of 0.5 and 1.5 mm.
Outcomes of decompression and fusion for treatment of spinal infection
Authors: Dietz Nicholas , Sharma Mayur , Alhourani Ahmad , Ugiliweneza Beatrice , Wang Dengzhi , Nuño Miriam , Drazin Doniel , Boakye Maxwell 
Published: February 2019

OBJECTIVESpine infection including vertebral osteomyelitis, discitis, paraspinal musculoskeletal infection, and spinal abscess refractory to medical management poses significant challenges to the treating physician. Surgical management is often required in patients suffering neurological deficits or spinal deformity with significant pain. To date, best practices have not been elucidated for the optimization of health outcomes and resource utilization in the setting of surgical intervention for spinal infection. The authors conducted the present study to assess the magnitude of reoperation rates in both fusion and nonfusion groups as well as overall health resource utilization following surgical decompression for spine infection.METHODSThe authors performed an analysis using MarketScan (2001–2015) to identify health outcomes and healthcare utilization metrics of spine infection following surgical intervention with decompression alone or combined with fusion. Adult patients underwent surgical management for primary or secondary spinal infection and were followed up for at least 12 months postoperatively. Assessed outcomes included reoperation, healthcare utilization and payment at the index hospitalization and within 12 months after discharge, postoperative complications, and infection recurrence.RESULTSA total of 2662 patients in the database were eligible for inclusion in this study. Rehospitalization for infection was observed in 3.99% of patients who had undergone fusion and in 11.25% of those treated with decompression alone. Reoperation was needed in 12.7% of the patients without fusion and 8.16% of those with fusion. Complications within 30 days were more common in the nonfusion group (24.64%) than in the fusion group (16.49%). Overall postoperative payments after 12 months totaled $33,137 for the nonfusion group and $23,426 for the fusion group.CONCLUSIONSIn this large cohort study with a 12-month follow-up, the recurrence of infection, reoperation rates, and complications were higher in patients treated with decompression alone than in those treated with decompression plus fusion. These findings along with imaging characteristics, disease severity, extent of bony resection, and the presence of instability may help surgeons decide whether to include fusion at the time of initial surgery. Further studies that control for selection bias in appropriately matched cohorts are necessary to determine the additive benefits of fusion in spinal infection management.
Spontaneous spondylodiscitis: review, incidence, management, and clinical outcome in 44 patients
Authors: Waheed Ghada , Soliman Mohamed A. R. , Ali Ahmed M. , Aly Mohamed H. 
Published: February 2019

OBJECTIVESpontaneous spondylodiscitis remains uncommon but is a serious complication of the vertebral column. Risk factors include diabetes, hemodialysis, intravenous drug abuse, and chronic steroid use, and pain is the most common presenting symptom. This study aims to review the literature and report on the incidence, management, and clinical outcome of spontaneous spondylodiscitis in 44 patients.METHODSThis is a prospective study including 44 patients with spontaneous spondylodiscitis managed in the neurosurgery department of Cairo University Hospitals during the period between January 2012 and October 2017. All patients had a full clinical assessment, laboratory tests, radiological studies in the form of MRI with and without contrast, and a postoperative follow-up of up to 12 months.RESULTSTwelve cases underwent conservative treatment in the form of complete bed rest, intravenous antibiotics, and a spinal brace. Ten cases underwent surgical intervention in the form of laminectomy, debridement, and open biopsy. Twenty-two cases underwent laminectomy and surgical stabilization with fusion. There were 15 cases of tuberculous spondylodiscitis, 6 cases of brucellosis, 6 cases of pyogenic infection, and 17 cases in which no organism could be detected.CONCLUSIONSOnce the primary diagnosis is confirmed, early and adequately prolonged antibiotic therapy is recommended for spontaneous spondylodiscitis. Some cases can be successfully treated with conservative treatment alone, whereas surgery may be needed in other cases such as severe destruction of endplates, spinal abscess formation, mechanical instability, neurological deficits, and severe pain that have failed to respond to conservative treatment.
The global neurosurgical workforce: a mixed-methods assessment of density and growth
Authors: Mukhopadhyay Swagoto , Punchak Maria , Rattani Abbas , Hung Ya-Ching , Dahm James , Faruque Serena , Dewan Michael C. , Peeters Sophie , Sachdev Sonal , Park Kee B. 
Published: February 2019

OBJECTIVEIn 2000, the global density of neurosurgeons was estimated at 1 per 230,000 population, which remains the most recent estimate of the global neurosurgeon workforce density. In 2004, the World Health Organization (WHO) estimated that there were 33,193 neurosurgeons worldwide, including trainees. There have been no updates to this estimate in the past decade. Moreover, only WHO region–level granularity regarding neurosurgeon distribution exists; country-level estimates are limited. The neurosurgery workforce is a crucial component to meeting the growing burden of neurosurgical diseases, which not only represent high absolute incidences and prevalences, but also represent correspondingly high disability-adjusted life years affecting hundreds of millions of people worldwide. Combining the lack of knowledge about the availability of the neurosurgical workforce and the increasing demand for neurosurgical services underscores the need for a system of neurosurgical workforce density surveillance.METHODSThis study involved 3 key steps: 1) global survey/literature review to obtain the number of working neurosurgeons per WHO-recognized country, 2) regression to interpolate any missing data, and 3) calculation of workforce densities and comparison to available historical data by WHO region.RESULTSData for 198 countries were collected (158) or interpolated (40). The global total number of neurosurgeons was estimated at 49,940. Overall, neurosurgeon density ranged from 0 to 58.95 (standardized to per 1,000,000 population) with a median of 3.56 (IQR 0.29–8.26). Thirty-three countries were found to have no neurosurgeons (zero). The highest density, 58.95, was in Japan, where 7495 neurosurgeons are taking care of a population of 127,131,800.CONCLUSIONSIn 2015, the Lancet Commission on Global Surgery estimated that 143 million additional surgical procedures are needed in low- and middle-income countries each year, and a subsequent study revealed that approximately 15% of those surgical procedures are neurosurgical. Based on our results, we can conclude that there are approximately 49,940 neurosurgeons currently, worldwide. The availability of neurosurgeons appears to have increased in all geographic regions over the past decade, with Southeast Asia experiencing the greatest growth. Such remarkable expansion should be assessed to determine factors that could play a role in other regions where the acceleration of growth would be beneficial.
Stereotactic radiosurgery with concurrent lapatinib is associated with improved local control for HER2-positive breast cancer brain metastases
Authors: Parsai Shireen , Miller Jacob A. , Juloori Aditya , Chao Samuel T. , Kotecha Rupesh , Mohammadi Alireza M. , Ahluwalia Manmeet S. , Murphy Erin S. , Barnett Gene H. , Vogelbaum Michael A. , Angelov Lilyana , Peereboom David M. , Suh John H. 
Published: February 2019

OBJECTIVEWith increasing survival for patients with human epidermal growth factor receptor 2-positive (HER2+) breast cancer in the trastuzumab era, there is an increased risk of brain metastasis. Therefore, there is interest in optimizing intracranial disease control. Lapatinib is a small-molecule dual HER2/epidermal growth factor receptor inhibitor that has demonstrated intracranial activity against HER2+ breast cancer brain metastases. The objective of this study was to investigate the impact of lapatinib combined with stereotactic radiosurgery (SRS) on local control of brain metastases.METHODSPatients with HER2+ breast cancer brain metastases who underwent SRS from 1997–2015 were included. The primary outcome was the cumulative incidence of local failure following SRS. Secondary outcomes included the cumulative incidence of radiation necrosis and overall survival.RESULTSOne hundred twenty-six patients with HER2+ breast cancer who underwent SRS to 479 brain metastases (median 5 lesions per patient) were included. Among these, 75 patients had luminal B subtype (hormone receptor-positive, HER2+) and 51 patients had HER2-enriched histology (hormone receptor-negative, HER2+). Forty-seven patients received lapatinib during the course of their disease, of whom 24 received concurrent lapatinib with SRS. The median radiographic follow-up among all patients was 17.1 months. Concurrent lapatinib was associated with reduction in local failure at 12 months (5.7% vs 15.1%, p < 0.01). For lesions in the ≤ 75th percentile by volume, concurrent lapatinib significantly decreased local failure. However, for lesions in the > 75th percentile (> 1.10 cm3), concurrent lapatinib did not significantly improve local failure. Any use of lapatinib after development of brain metastasis improved median survival compared to SRS without lapatinib (27.3 vs 19.5 months, p = 0.03). The 12-month risk of radiation necrosis was consistently lower in the lapatinib cohort compared to the SRS-alone cohort (1.3% vs 6.3%, p < 0.01), despite extended survival.CONCLUSIONSFor patients with HER2+ breast cancer brain metastases, the use of lapatinib concurrently with SRS improved local control of brain metastases, without an increased rate of radiation necrosis. Concurrent lapatinib best augments the efficacy of SRS for lesions ≤ 1.10 cm3 in volume. In patients who underwent SRS for HER2+ breast cancer brain metastases, the use of lapatinib at any time point in the therapy course was associated with a survival benefit. The use of lapatinib combined with radiosurgery warrants further prospective evaluation.
Recovery time from supplementary motor area syndrome: relationship to postoperative day 7 paralysis and damage of the cingulum
Authors: Nakajima Riho , Kinoshita Masashi , Yahata Tetsutaro , Nakada Mitsutoshi 
Published: February 2019

OBJECTIVESupplementary motor area (SMA) syndrome is defined as temporary paralysis after the resection of brain tumor localized in the SMA. Although in most cases paralysis induced by SMA resection resolves within a short period, the time until complete recovery varies and has not been precisely analyzed to date. In this study, the authors investigated factors for predicting the time required for recovery from paralysis after SMA resection.METHODSData from 20 cases were analyzed. All 20 patients (mean age 54.9 ± 12.6 years) had undergone resection of frontal lobe glioma involving the SMA. The severity of postoperative paralysis was recorded until complete recovery using the Brunnstrom recovery stage index. To investigate factors associated with recovery time, the authors performed multivariate analysis with the following potentially explanatory variables: age, severity of paralysis after the surgery, resected volume of the SMA, and probability of disconnection of fibers running through or near the SMA. Moreover, voxel-based lesion symptom analysis was performed to clarify the resected regions related to prolonged recovery.RESULTSIn most cases of severe to moderate paralysis, there was substantial improvement within the 1st postoperative week, but 2–9 weeks were required for complete recovery. Significantly delayed recovery from paralysis was associated with resection of the cingulate cortex and its deep regions. The factors found to influence recovery time from paralysis were stage of paralysis at postoperative day 7 and disconnection probability of the cingulum (adjusted R2 = 0.63, p < 0.0001).CONCLUSIONSRecovery time from paralysis due to SMA syndrome can be predicted by the severity of paralysis at postoperative day 7 and degree of damage to the cingulum.
Infection risk in endovascular neurointerventions: a comparative analysis of 549 cases with and without prophylactic antibiotic use
Authors: Burkhardt Jan-Karl , Tanweer Omar , Litao Miguel , Sharma Pankaj , Raz Eytan , Shapiro Maksim , Nelson Peter Kim , Riina Howard A. 
Published: February 2019

OBJECTIVEA systematic analysis on the utility of prophylactic antibiotics for neuroendovascular procedures has not been performed. At the authors’ institution there is a unique setup to address this question, with some attending physicians using prophylactic antibiotics (cefazolin or vancomycin) for all of their neurointerventions while others generally do not.METHODSThe authors performed a retrospective review of the last 549 neurointerventional procedures in 484 patients at Tisch Hospital, NYU Langone Medical Center. Clinical and radiological data were collected for analysis, including presence of prophylactic antibiotic use, local or systemic infection, infection laboratory values, and treatment. Overall, 306 aneurysms, 117 arteriovenous malformations/arteriovenous fistulas, 86 tumors, and 40 vessel stenosis/dissections were treated with coiling (n = 109), Pipeline embolization device (n = 197), embolization (n = 203), or stenting (n = 40).RESULTSAntibiotic prophylaxis was used in 265 of 549 cases (48%). There was no significant difference between patients with or without antibiotic prophylaxis in sex (p = 0.48), presence of multiple interventions (p = 0.67), diseases treated (p = 0.11), or intervention device placed (p = 0.55). The mean age of patients in the antibiotic prophylaxis group (53.4 years) was significantly lower than that of the patients without prophylaxis (57.1 years; p = 0.014). Two mild local groin infections (0.36%) and no systemic infections (0%) were identified in this cohort, with one case in each group (1/265 [0.38%] vs 1/284 [0.35%]). Both patients recovered completely with local drainage (n = 1) and oral antibiotic treatment (n = 1).CONCLUSIONSThe risk of infection associated with endovascular neurointerventions with or without prophylactic antibiotic use was very low in this cohort. The data suggest that the routine use of antibiotic prophylaxis seems unnecessary and that to prevent antibiotic resistance and reduce costs antibiotic prophylaxis should be reserved for selected patients deemed to be at increased infection risk.
Characteristics and career outcomes of Neurosurgery Research and Education Foundation research fellowship recipients
Authors: Wilson Taylor A. , Langston Rebekah G. , Wong Ka Hin , Rodriguez Analiz 
Published: February 2019

OBJECTIVEThe American Association of Neurological Surgeons (AANS) Neurosurgery Research and Education Foundation (NREF) provides ongoing competitive research fellowships for residents and young investigators. The authors sought to determine the characteristics and career tracks of award recipients.METHODSThe authors analyzed characteristics and academic productivity parameters of NREF resident and young investigator awardees in the United States and Canada from 1983 to 2017. Data were extracted from the NREF database and online resources (Web of Science, NIH reporter).RESULTSIn total, 224 research grants were awarded to 31 women (14%) and 193 men (86%) from 1983 to 2017. Neuro-oncology (36%) was the most common research category. Sixty percent of awardees were in training and most resident award winners were in postgraduate year 5 (37%). Forty-nine percent of all awardees had an additional postgraduate degree (PhD 39%, Master’s 10%) with a significantly higher number of PhD recipients being from Canada in comparison to any US region (p = 0.024). The Northeastern and Southeastern United States were the regions with the highest and lowest numbers of award recipients, respectively. More than one-third (40%) of awardees came from institutions that have a National Institute of Neurological Disorders and Stroke Research Education Grant (NINDS R25) for neurosurgical training. Awardees from NINDS R25–funded programs were significantly more likely to go on to receive funding from the National Institutes of Health (NIH) (40.4% vs 26.1%; p = 0.024). The majority of recipients (72%) who were no longer in training pursued fellowships, with a significant likelihood that fellowship subspecialty correlated with NREF research category (p < 0.001). Seventy-nine percent of winners entered academic neurosurgery practice, with 18% obtaining the position of chair. The median h-index among NREF winners was 11. NIH funding was obtained by 71 awardees (32%) with 36 (18%) being a principal investigator on an R01 grant from the NIH Research Project Grant Program.CONCLUSIONSThe majority of AANS/NREF research award recipients enter academics as fellowship-trained neurosurgeons, with approximately one-third obtaining NIH funding. Analysis of this unique cohort allows for identification of characteristics of academic success.
Clinical factors influencing the development of extracranial-intracranial bypass graft for steno-occlusive cerebrovascular disease
Authors: Nomura Shunsuke , Yamaguchi Koji , Ishikawa Tatsuya , Kawashima Akitsugu , Okada Yoshikazu , Kawamata Takakazu 
Published: February 2019

OBJECTIVEEffectively retaining the patency of the extracranial-intracranial (ECIC) bypass is one of the most important factors in improving long-term results; however, the factors influencing bypass patency have not been discussed much. Therefore, the authors investigated factors influencing the development of the bypass graft.METHODSIn this retrospective study, the authors evaluated 49 consecutive hemispheres in 47 adult Japanese patients who had undergone ECIC bypass for chronic steno-occlusive cerebrovascular disease. To evaluate objectively the development of the ECIC bypass graft, the change in the area of the main trunk portion of the superficial temporal artery (STA) from before to after bypass surgery (postop/preop STA) was measured. Using the interquartile range (IQR), the authors statistically analyzed the factors associated with excellent (> 3rd quartile) and poor development (< 1st quartile) of the bypass graft.RESULTSThe postop/preop STA ranged from 1.08 to 6.13 (median 1.97, IQR 1.645–2.445). There was a significant difference in the postop/preop STA between the presence and absence of concurrent diabetes mellitus (p = 0.0432) and hyperlipidemia (0.0069). Furthermore, logistic regression analysis revealed that only concurrent diabetes mellitus was significantly associated with poor development of the bypass graft (p = 0.0235).CONCLUSIONSDiabetes mellitus and hyperlipidemia influenced the development of the ECIC bypass graft. In particular, diabetes mellitus is the only factor associated with poor development of the bypass graft.