bluuebunny/crossref_metadata_2025_split huggingface dataset:
707 Associations Between Inflammatory Markers and Outcomes in SICH
Authors: Ong Shi Hui , Zheng Yilong , Nga Vincent , Teo Kejia , Yeo Tseng Tsai , Rui Lim Mervyn Jun 
Published: March 2024

INTRODUCTION:
Studies have shown that higher neutrophil-lymphocyte ratio (NLR) significantly associated with poorer outcomes. However, most studies evaluated ischemic stroke and did not look at other markers such as platelet-lymphocyte ratio (PLR), platelet-white cell ratio (PWR) and platelet-neutrophil ratio (PNR). Wang et al demonstrated NLR had no correlation with mortality in spontaneous intracerebral hemorrhage (SICH).

METHODS:
We included 1001 patients with SICH diagnosed on computed tomography of the brain from January 2014 to December 2021. Good functional outcomes were defined as modified Rankin Scale (mRS) 0 to 2 while bad outcomes were defined as 3 to 6. Logistic regression was used to adjust for demographics (Model 1), cardiovascular risk factors (Model 2), bleed characteristics (Model 3) and baseline GCS (Model 4). Statistical analysis was done with R Studio.

RESULTS:
Logistic regression showed that NLR (OR: 1.03, 95% CI: 1.00-1.06, p < .05), PWR (OR: 0.98, 95% CI: 0.96-1.00, p < .05) and PNR (OR: 0.98, 95% CI: 0.97-0.99, p < .01) were significantly associated with 30-day mortality even after adjusting for confounders. However, PNR became non-significant after adjusting for bleed characteristics and GCS. When comparing 90-day functional outcome, only PWR (OR: 1.03, 95% CI: 1.01-1.04, p < .01) and PNR (OR: 1.01, 95% CI: 1.00-1.01, p < .05) demonstrated significant association even after adjusting for demographics and cardiovascular risk factors.

CONCLUSIONS:
In conclusion, NLR and PWR were independently and statistically associated with 30-day mortality. Further research on the value of ratios of inflammatory cells in prognosticating outcomes may help improve patient management.
724 Population Per State Served by a Neurosurgery Resident: A National Review
Authors: Stevenson Taylor C. , Rai Karan , Ellenbogen Richard G. 
Published: March 2024

INTRODUCTION:
Neurosurgery residency remains challenging, with 7-years of post-graduate training offered at only 116 locations. It's typically the longest route to board certification of all surgical and medical specialties, yet its programs often consist of the smallest cohorts. Furthermore, the breadth of pathology and populations served by each neurological residency varies significantly.

METHODS:
Doximity residency “navigator” was used to query total residency programs that entered the 2022-2023 match cycle. U.S. state populations were collected from World Population Review Census January 2023. States were arranged from highest to lowest by census population. Each state population was divided by the NS resident positions in that state. The population per resident (PPR) were compared.

RESULTS:
California and Wyoming contained the largest and smallest state populations, respectively at 40,223,504 and 580,817. Vermont was the smallest state to contain a NS program with a population of 648,279 and 7 residency positions or roughly 92,611 PPR. California comparatively contained 151 positions or 266,381 PPR. Interestingly, New York and Florida each contain roughly 21 million people, yet they respectively contained 115,527 and 354,909 PPR. In total 65% of residents served between 127,920 to 306,528 people depending on the state.

CONCLUSIONS:
There is a wide range in the number of people served by each NS resident throughout the USA. Neurological Surgery residencies are not located uniformly by population and patients are free to travel across state boundaries. Currently the ACGME determines program expansion and creation by uniform specialty specific standards. Our data presents a new lens for discussing maximization of training opportunities across the continental United States.
756 A 3D Deep-learning Based Algorithm for Cerebral Vessel and Aneurysm Segmentation From CTA Images
Authors: Patel Tatsat , Patel Aakash , Veeturi Sricharan , Shah Munjal , Waqas Muhammad , Baig Ammad , Monteiro Andre , Pinter Nandor , Levy Elad I. , Siddiqui Adnan Hussain , Tutino Vincent 
Published: March 2024

INTRODUCTION:
Computed tomography angiography (CTA) is the most widely used imaging modality for intracranial aneurysm (IA) management, yet it remains inferior to digital subtraction angiography (DSA) for IA detection, particularly of small IAs in the cavernous carotid region.

METHODS:
Using 50 paired CTA-DSA images, we trained (n = 27), validated (n = 3) and tested (n = 20) a deep-learning model (3D-DeepMedic) for cerebrovasculature segmentation from CTA. A landmark-based co-registration algorithm was used for registration and up-sampling of CTAs to paired DSAs. Segmented vessels from DSAs were used as the ground-truth. Accuracy of the model was evaluated using conventional metrics (dice similarity coefficient-DSC) and vessel-specific metrics, like connectivity-area-length (CAL). On the test cases (20 IAs), 3 experts detected and segmented IAs. For each rater, we recorded the rate of IA detection. For detected IAs, raters segmented IAs and calculated morphology parameters to quantify the differences in IA segmentation by raters to DeepMedic. The rater agreements were assessed using Krippendorf’s alpha.

RESULTS:
In testing, the DeepMedic model yielded a DSC and CAL of 0.971 ± 0.007 and 0.868 ± 0.008, respectively. The model delineated all IAs with errors <10% for all IA morphometrics. Conversely, average IA detection accuracy from raters was 0.653 (undetected IAs were present to a significantly greater degree on the ICA cavernous region and were significantly smaller). Error rates for IA morphometrics in rater-segmentations were significantly higher than in DeepMedic-segmentations, particularly for neck (p = 0.003), and surface-area (p = 0.003). For IA morphology, agreement between the raters was acceptable for metrics except UI (α=0.36) and NSI (α=0.69). The agreement between DeepMedic and ground truth was consistently higher.

CONCLUSIONS:
Our CTA segmentation algorithm provides a high-fidelity solution for CTA vessel segmentation, particularly for vessels and IAs in the carotid cavernous region.
789 The Impact of Social Determinants on Adjuvant Radiation Following Atypical Meningioma Surgery
Authors: Chisango Zvipo , Ugochukwu Obiadada , Zhi Xiaojie Jessie , Bray David Painton , Hoang Kimberly Bojanowski 
Published: March 2024

INTRODUCTION:
WHO grade 2 meningiomas or ‘atypical meningiomas’ are a subset of meningioma associated with higher morbidity and mortality. Adjuvant radiotherapy is increasingly shown to improve survival and reduce recurrence in these tumors.

METHODS:
The National Cancer Database was queried for patients receiving atypical meningioma surgery between 2004 and 2019. Univariate association, univariate regression and multivariate regression were performed on 8,654 patients to assess the association between receipt of adjuvant radiation and social determinants. Secondarily, KM curves were used to compare overall patient survival between those that received radiation and those that did not.

RESULTS:
Adjuvant radiation was less likely to be administered to patients over age 65 (95% CI = 0.53-0.77) and more likely to be administered to males (95% CI = 1.07–1.38). Compared to the Southern USA, patients were more likely to receive radiotherapy in the Northeastern (95% CI = 1.40–2.05), Midwestern (95% CI =1.06–1.54), and Western parts of the United States (95% CI = 1.31–2.00). Patients residing furthest from the reporting facility were less likely to receive radiation (95% CI = 0.65–0.98). Patients with any kind of insurance were more likely to receive radiation (p = 0.048) than those without insurance. On multivariate analysis, no differences were found between racial groups regarding adjuvant radiation, however the univariate analysis demonstrated that compared to non-hispanic whites, non-hispanic blacks were less likely to receive radiation (95% CI = 0.64-0.94) and Asian/Pasic Islanders were more likely to receive radiation (95% CI = 1.03–1.79).

CONCLUSIONS:
We reveal that disparities in administration of adjuvant RT exist based on female sex, age > 65, uninsured status, distance from the treating facility, and facility regional location.
925 Concordance Between CSF Cytology and MR Imaging in the Detection of Leptomeningeal Dissemination in Patients With Medulloblastomas
Authors: Peeran Zain , Phelps Ryan R. L. , Aabedi Alexander Arash , Rios Jennifer , Reddy Alyssa , Aghi Manish Kumar , Gupta Nalin 
Published: March 2024

INTRODUCTION:
In patients with medulloblastomas, the combination of CSF cytology and MR imaging is believed to be superior to either tool alone in detecting leptomeningeal dissemination (LMD). However, MRI has drastically improved since the initial assessment of this approach.

METHODS:
A retrospective review of 117 unique patients with medulloblastomas from a single institution was conducted. CSF samples and MR images obtained within 36 days of each other were included. A 3-tier system (negative, atypical/suspicious, positive) was utilized to account for equivocal findings. A total of 253 CSF-MRI pairs (range: 1-12 pairs per patient) obtained between 2000-2021 were analyzed.

RESULTS:
The mean (SD) age of this cohort was 14.1 (13.5) years (62.4% were male). Gross total resection with surgery was achieved in 64.5%, 83.7% received radiotherapy, 81.5% received chemotherapy. 16.2% were deceased, with the mean (SD) time till death being 4.6 (4.7) years following the first operation. The molecular subtypes were: SHH (17.0%), WNT (3.6%), non-WNT/non-SHH (46.6%), unknown (32.8%). There was a 60.5% concordance between CSF cytology and MRI, with no significant differences by molecular subtype. In 57.3% of cases, CSF cytology and MRI were both negative. In 1.2% of cases, CSF cytology and MRI were both equivocal. 26.9% of cases were positive on CSF cytology and/or MRI. MRI had an 86.8% sensitivity and CSF cytology had a 20.6% sensitivity for detecting LMD that was positive in CSF, MRI, or both. In 10 cases (4.0%), MRI was negative when CSF was atypical or positive. In 80 cases (31.6%), CSF was negative when MRI was positive or suspicious. In 94.5% of cases, MRI demonstrated greater or equal ability to CSF cytology in detecting LMD.

CONCLUSIONS:
MRI is superior to CSF cytology in detecting LMD but misses a small percentage of cases.
Influence of Surgical Resection on Survival in Glioblastoma with Multiple Localizations—a Multi-Center Retrospective Analysis
Authors: Jankovic Dragan , Krenzlin Harald , Dauth Alice , Lange Felipa , Keric Naureen , Ringel Florian 
Published: March 2024

INTRODUCTION:
The presence of multiple localizations in glioblastoma is rare and associated with poor prognosis. The presence of a visible junction between enhancing lesions on magnetic resonance imaging (MRI) is defined as multifocal (MF), the absence of a dissemination pathway as multicentric (MC).

METHODS:
Data collection was performed as a multicenter retrospective analysis. From Jan 1, 2008, to Dec 31, 2020 patients presenting with IDH wild-type glioblastoma (CNS WHO grade 4) with multiple localizations were included. Demographic data, tumor size, Karnofsky Performance Score (KPS) before and after surgery were analyzed. EOR was measured by FLAIR and contrast-enhanced MRI. Gross total resection (GTR, residual tumor (RTM) < 5%), subtotal resection (STR, RTM < 30%), partial resection (PR, RTM > 30%), and biopsy (RTM > 75%).

RESULTS:
This study included 117 patients with a median age of 62 years. 45 (38.5%) patients had MC lesions, 72 (61.5%) MF. Median KPS on admission was similar in both subtypes. Median OS did not differ among MC and MF glioblastomas. In MF glioblastoma, GTR (p = 0.0001) and STR (p = 0.0001) significantly increased the median OS compared to PR and biopsy. Likewise, OS was increased after GTR (p = 0.0272) and STR (p = 0.0272) in MC glioblastoma, as well. Overall, resection significantly increased OS in patients with glioblastoma with multiple localizations compared to biopsy alone. In multivariate logistic regression analysis EOR and chemotherapy were significant and independent predictors of OS in MC and MF glioblastomas.

CONCLUSIONS:
These data indicate that GTR and STR positively affects OS in patients with MC and MF glioblastoma. These results argue for a more aggressive stance towards surgical treatment of these tumors with particularly poor prognosis, even when GTR is not within reach before resection.
Heterozygous CDKN2A Loss is Associated with Recurrence and Survival in High, But Not Low Grade Meningiomas
Authors: Tabor Joanna , O'Brien Joseph , Morales Valero Saul F. , Pappajohn Alexandros , McGuone Declan , Erson-Omay Zeynep , Yasuno Katsuhito , Gunel Murat , Moliterno Jennifer A. 
Published: March 2024

INTRODUCTION:
Homozygous loss of CDKN2A/B is associated with more aggressive meningiomas and is now considered in the updated WHO grading criteria. The relevance of heterozygous loss (hetloss) of CDKN2A/B is less clear and the potential association of hetloss CDKN2A with aggressive meningioma phenotype remains underexplored.

METHODS:
Clinical and whole exome sequencing data for patients who underwent resection of sporadic meningiomas were analyzed.

RESULTS:
Of the 564 meningiomas included, 16 tumors harbored hetloss of CDKN2A; 7 of these were low grade (WHO grade I) and 9 high grade (grade II or III). Compared to high-grade hetloss meningiomas, low-grade ones were less likely to have an NF2 somatic driver mutation (p = 0.041) and were more common along the skull base (p = 0.005). Low-grade meningiomas with hetloss CDKN2A had more aggressive clinical characteristics compared to wild type (WT), with higher proliferative indices (p = 0.044), increased cellularity (p = 0.032) and higher copy number variations (p = 0.004) and patients were more likely to be symptomatic (p = 0.007); there was no difference in progression-free survival (PFS) (p = 0.4). High-grade hetloss CDKN2A meningiomas, however, had higher mitotic count (p = 0.014), increased chromosomal instability (p = 0.004), and higher recurrence rates (p < 0.001), as well as decreased PFS (p < 0.001) and overall survival (OS) (p = 0.002), compared to high-grade WT. Interestingly, these findings remained significant amongst high-grade hetloss CDKN2A meningiomas even when controlling for underlying NF2 mutation.

CONCLUSIONS:
Hetloss of CDKN2A is associated with more aggressive histological and genomic characteristics in both low- and high-grade meningiomas. Only high-grade meningiomas with hetloss CDKN2A, however, differ from those without the mutation in recurrence and PFS. This effect does not seem related to underlying somatic NF2 mutation. These findings may have clinical implications for high-grade meningiomas harboring heterozygous CDKN2A mutations.
The Ribbon Sign as a Radiological Indicator of Intramedullary Spinal Cord Subependymomas
Authors: Rincon-Torroella Jordina , Hersh Andrew M. , Liu Ann , Sair Haris I. , Lubelski Daniel , Bettegowda Chetan , Shimony Nir , Larry Lo Sheng-Fu , Sciubba Daniel M. , Jallo George I. 
Published: March 2024

INTRODUCTION:
Intramedullary spinal cord (IMSC) subependymomas are rare World Health Organization grade 1 ependymal tumors. The potential presence of functional neural tissue within the tumor and poorly demarcated planes presents a risk to resection. Recognition of an intramedullary subependymoma on preoperative imaging can assist in operative planning and factor into the decision-making for gross- or sub-total resection. However, no definitive pathognomonic features have been reported on magnetic resonance imaging (MRI).

METHODS:
We retrospectively reviewed preoperative MRIs of patients presenting with IMSC tumors at a large tertiary academic institution between April 2005 and January 2022. The diagnosis was confirmed histologically. The “ribbon sign” was defined as a ribbon-like structure of T2 isointense spinal cord tissue interwoven between regions of T2 hyperintense tumor. The ribbon sign was confirmed by an expert neuroradiologist.

RESULTS:
MRIs from 151 patients were reviewed, including 42 (28%) astrocytomas, 82 (54%) ependymomas, 8 (5.3%) gangliogliomas, and 19 (13%) hemangioblastomas. Of the 82 ependymomas, ten patients (12%) presented with intramedullary subependymomas. The ribbon sign was demonstrated on nine (90%) patients with histologically proven subependymomas. No other tumor types displayed the ribbon sign.

CONCLUSIONS:
The ribbon sign is a distinctive imaging feature of IMSC subependymomas and indicates the presence of spinal cord tissue between eccentrically located tumor. Recognition of the sign should prompt clinicians to consider a diagnosis of subependymoma. Unlike their intracranial counterparts, resection of these lesions can be technically difficult, particularly in cases with poor demarcation between cord and tumor. Therefore, the risks and benefits of gross- vs. sub-total resection should be carefully considered and discussed with patients.
The use of click chemistry in sphingolipid research
Authors: Jamecna Denisa , Höglinger Doris 
Published: March 2024

ABSTRACT
Sphingolipid dysregulation is involved in a range of rare and fatal diseases as well as common pathologies including cancer, infectious diseases or neurodegeneration. Gaining insights into how sphingolipids are involved in these diseases would contribute much to our understanding of human physiology, as well as the pathology mechanisms. However, scientific progress is hampered by a lack of suitable tools that can be used in intact systems. To overcome this, efforts have turned to engineering modified lipids with small clickable tags and to harnessing the power of click chemistry to localize and follow these minimally modified lipid probes in cells. We hope to inspire the readers of this Review to consider applying existing click chemistry tools for their own aspects of sphingolipid research. To this end, we focus here on different biological applications of clickable lipids, mainly to follow metabolic conversions, their visualization by confocal or superresolution microscopy or the identification of their protein interaction partners. Finally, we describe recent approaches employing organelle-targeted and clickable lipid probes to accurately follow intracellular sphingolipid transport with organellar precision.
On the geometric interpretation of quaternions by cones
Authors: Scheglov Georgiy 
Published: March 2024

The geometric interpretation of quaternions is considered. The visualization complexity of quaternions is due to the fact that these objects have four independent parameters. A literature analysis shows that the problem of geometric interpretation of quaternions has not been completely solved to date.
The first section provides general provisions on quaternions and the necessary notations. The second section describes the classical geometric interpretation of quaternions by arcs on a unit sphere. The third section describes a new geometric interpretation and its application to the problem of a vector finite rotation.
The geometric interpretation of the quaternion as the surface of a right circular cone is presented. This representation allow demonstrating it as a holistic object in which the scalar and vector parts are interconnected, taking into account their modules and signs.
For the considered normalized quaternion, it is easy to understanding an important entity, the quaternion versor: in general, it is a cone, which in the limiting case of a pure scalar quaternion transform into a sphere, and in the limiting case of a pure vector quaternion transform into an ordinary vector. This distinctive feature of the proposed geometric interpretation makes it possible, even when projected onto a plane, to clearly distinguish visualization of the quaternions with a nonzero scalar part from pure vector quaternions, which is difficult to do in the other known interpretations. The representation of quaternions by cones clearly demonstrates the need for a double quaternion product, when the vector is rotated around an arbitrary axis.
Images of quaternions as cones, spheres and vectors can be useful in the study of quaternion algebra, which is currently finding increasing use in engineering.
Fair Exploration via Axiomatic Bargaining
Authors: Baek Jackie , Farias Vivek F. 
Published: March 2024

Exploration is often necessary in online learning to maximize long-term rewards, but it comes at the cost of short-term “regret.” We study how this cost of exploration is shared across multiple groups. For example, in a clinical trial setting, patients who are assigned a suboptimal treatment effectively incur the cost of exploration. When patients are associated with natural groups on the basis of, say, race or age, it is natural to ask whether the cost of exploration borne by any single group is “fair.” So motivated, we introduce the “grouped” bandit model. We leverage the theory of axiomatic bargaining, and the Nash bargaining solution in particular, to formalize what might constitute a fair division of the cost of exploration across groups. On one hand, we show that any regret-optimal policy strikingly results in the least fair outcome: such policies will perversely leverage the most “disadvantaged” groups when they can. More constructively, we derive policies that are optimally fair and simultaneously enjoy a small “price of fairness.” We illustrate the relative merits of our algorithmic framework with a case study on contextual bandits for warfarin dosing where we are concerned with the cost of exploration across multiple races and age groups. This paper was accepted by David Simchi-Levi, data science. Funding: This work was supported by the National Science Foundation, Division of Civil, Mechanical and Manufacturing Innovation [Grant 1727239]. Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2022.01985 .
Nickel composite film for terahertz wave broadband absorption
Authors: Liu Quanjun , Hu Fangrong , Su An , Jiang Mingzhu , Zhang Longhui , Song Zihang 
Published: March 2024

Due to the poor response of natural materials in the terahertz (THz)
frequency band, ultra-broadband absorption of THz waves is a
challenge. In this work, a nickel-composite film (NCF) is
experimentally demonstrated for the ultra-broadband absorption of THz
waves. The NCF consists of nickel foam, polydimethylsiloxane (PDMS),
and few-layer graphene. The nickel foam has a three-dimensional
structure that can be filled by the PDMS and few-layer graphene. By
controlling the mass fraction of few-layer graphene in the PDMS, we
can reduce the surface reflection of THz waves and achieve broadband
absorption. For a 0.5-mm-thick NCF, when the mass fraction of doped
few-layer graphene is 2%, the qualified bandwidth (with an absorption
rate more than 90%) reaches 3.2 THz. More importantly, for
different thicknesses of nickel foams, the absorption bandwidth can be
enhanced by changing the mass fraction of few-layer graphene.