bluuebunny/crossref_metadata_2025 huggingface dataset:
Regresi Binomial Negatif untuk Memodelkan Kematian Bayi di Kalimantan Timur
Authors: Fathurahman M
Published: May 2024

Negative Binomial Regression (NBR) is an alternative regression model to model the relationship between the dependent variable in overdispersion count data and one or more independent variables. Overdispersion is a problem in Poisson regression modeling. Namely, the variance of the dependent variable is more than the mean. If there is overdispersion, then the parameter estimator of the Poisson regression model has a standard error value that is not under-estimated. The NBR model was applied to modeling infant mortality in East Kalimantan in 2019. Data on infant mortality in East Kalimantan in 2019 indicated overdispersion. Infant mortality is an indicator that can measure the progress of development outcomes in the health sector in a region. In the last three years, from 2017 to 2019, infant mortality data in East Kalimantan has increased. Therefore, it is necessary to do modeling to get the factors that cause it. The modeling results with NBR show that the percentage of the complete neonatal visit of KN3, the percentage of infant health services, and the percentage of visits by pregnant women K4 significantly affect infant mortality in East Kalimantan in 2019.
Penyelesaian Masalah Pemrograman Kuadratik Menggunakan Metode Beale
Authors: Erlina Erlina , Syaripuddin Syaripuddin , Amijaya Fidia Deny Tisna
Published: May 2024

Quadratic programming is a special form of nonlinear programming which has the general form of the objective function in the form of a quadratic functions and the constraints in the form of linear functions. One of the methods used to solve the quadratic programming model is Beale’s method. This method is a modification of the simplex method for linear programming problems. This study aims to determine the optmal results of paddy production data in Balikpapan city using Beale’s method. The quadratic programming model was formed using the least squares method with the objective functions by selecting two types of plants,namely lowland paddy and upland paddy. Furthermore, the quadratic programming model formed that is formed is solved using Beale’s method. The data used is data on the paddy production of balikpapan city in 2005-2019.  Based on the calculatios, the objective function is  with the constraint functions  and . After calculating using Beale’s method, the optimal result for the maximum yield of lowland paddy and upland paddy is  quintals with a harvested area of   hectares of lowland paddy and a harvested paddy of hectares of upland paddy.
ANALISA PENERAPAN PUTUSAN ULTRA PETITA OLEH MAHKAMAH KONSTITUSI DALAM PUTUSAN PERSELISIHAN HASIL PEMILIHAN UMUM
Authors: Putri Ratu Syifa Junaedi , Farhan Alif , Wasistha Ariani Nurhanifah Putri
Published: May 2024

The Constitutional Court is a particular judicial state institutions that has a position as a judicial institution besides the Supreme Court. Their responsibilities and power are controlled in Article 24C paragraph (1) of the 1945 Constitution of the Republic of Indonesia, where one of them is determining disputes over the outcome of the presidential elections. Requests for these types of issues may only be submitted by election participants considering the rules and regulations provided in Law no. 24 of 2003. In giving a decision, the judge has the right to find his own law, including giving a decision that exceeds the application submitted by the applicant which is called a decisionultra small. This is intended to provide substantive justice to the applicants. The objective of doing  this research is to analyze whether the decisionultra smallcan be applied in the issue of disputes over election results. For this reason, , a normative research was conducted using a qualitative methodology so that the results provided are a comprehensive discussion. The outcomes from this research prove that the verdictultra smallcan be given to cases of disputed election results. Example of applicationultra small against the action of the Constitutional Court is the Constitutional Court Decision Number 41/PHPU.D-VI/2008 and the Constitutional Court Decision Number 57/PHPU.D-VI/2008.Keywords:ultra petita, verdict, election dispute
The role of long-term hair steroids as diagnostic and intervention-related markers in a multimorbid inpatient sample with posttraumatic stress disorder
Authors: Shkreli Lorika , Woud Marcella Lydia , Bergunde Luisa , Gmelch Lena , Blackwell Simon Edward , Kirschbaum Clemens , Kessler Henrik , Schmiedgen Susann
Published: May 2024

Steroid hormone dysregulations have frequently been implicated in posttraumatic stress disorder (PTSD) pathogenesis. However, the translation into naturalistic clinical settings as markers of symptomatology and treatment success remains complex. Particularly, there is little longitudinal data on steroid secretion over the course of interventions. This study examined the potential of long-term steroid hormone secretion assessed in hair as diagnostic and intervention-related biomarkers among medicated, multimorbid inpatients with PTSD. As part of a secondary analysis of a randomized controlled trial, 54 female inpatients with a primary diagnosis of PTSD receiving standardised treatment provided hair samples at pre-treatment, post-treatment, and 3-months follow-up. Cortisol, cortisone, and dehydroepiandrosterone (DHEA) were determined, alongside clinical assessments. Cross-sectional results showed a negative association of pre-treatment DHEA with anxiety symptoms and a trend-level association with lifetime trauma exposure. While inpatients improved in PTSD symptomatology during treatment, neither pre-treatment steroids, nor treatment-induced steroid changes predicted PTSD symptoms at post-treatment or follow-up. The study highlights the challenges of establishing biomarkers in naturalistic clinical populations. While the association of attenuated DHEA with anxiety symptoms warrants further exploration, our data points towards the potential necessity of patient sub-sample selection to understand, and in the long run clinically target, the endocrine mechanisms in PTSD.
Clarifying the reliability paradox: poor test-retest reliability attenuates group differences
Authors: Karvelis Povilas , Diaconescu Andreea Oliviana
Published: May 2024

Cognitive sciences are grappling with the reliability paradox: measures that robustly produce within-group effects tend to have low test-retest reliability, rendering them unsuitable for studying individual differences. Despite the growing awareness of this paradox, its full extent remains underappreciated. Specifically, most research focuses exclusively on how reliability affects correlational analyses of individual differences, while largely ignoring its effects on studying group differences. Moreover, by conflating within- and between-group effects, some studies erroneously suggest that poor reliability does not pose problems for studying group differences. This brief report aims to clarify this misunderstanding through simple data simulations. To make the argument more intuitive, we consider two illustrative cases: comparing patients versus controls and comparing two groups formed by a median split. We demonstrate that reliability attenuates observed group differences just as much as it attenuates individual differences. Given that dichotomizing/grouping continuous data - which is implicit in many group differences analyses - leads to a loss of statistical power, low reliability proves to be even more problematic for studying group differences. While here we focused on cognitive sciences and psychiatry, our findings are quite general and could inform many other areas of research, including education, sex, gender, age, race, ethnicity, etc.
Empowering Language Learners’ Critical Thinking: Evaluating ChatGPT’s Role in English Course Implementation
Authors: Avsheniuk Nataliia , Lutsenko Olena , Svyrydiuk Tetiana , Seminikhyna Nataliya
Published: May 2024

This study investigates the influence of ChatGPT on critical thinking and English language learning within Ukrainian university English departments. Utilizing qualitative and quantitative methods, it involved 31 students and three language instructors in surveys and ChatGPT-assisted project-based activities. The significance of this study lies in its potential to guide the integration of AI tools in educational contexts, particularly in language learning. By examining the benefits and challenges of using ChatGPT, the study provides insights into how AI can support or hinder language learning and critical thinking. This is particularly relevant in the context of rapidly evolving educational technologies and the increasing use of AI in academic settings. In the spring semester of 2023, a research study was carried out involving students participating in a project-based activity using ChatGPT. The study comprised two main phases: initial survey, project completion, and evaluation. Quantitatively, it was found that 62% of students use ChatGPT weekly, underlining its role in their language studies. The results showed varied perspectives on its efficacy, especially in critical thinking, English skills development, and ethical considerations. Ethical and pedagogical issues were also significant, including concerns about the authenticity of AI responses, plagiarism risks, and AI dependency. Nevertheless, the potential advantages of ChatGPT, such as immediate language support and the promotion of learner independence, were acknowledged by students. The research concludes by recommending a careful integration of AI in language education.
How Do Counties’ Industry Structures Shape Cardiovascular Disease Mortality?
Authors: Sun Yue
Published: May 2024

Industry structures refer to the employment opportunities provided by different industries. Different industries are associated with various environmental and socioeconomic consequences. However, less is known about whether and how industry structures influence population health. In this study, I examine the associations between counties’ industry structures and cardiovascular disease (CVD) mortality in the United States for 2016-2018, and explore the environmental, economic, and health care mechanisms that may explain these associations. Using Ordinary Least Squares regressions and Karlson-Holm-Breen mediation analysis, I find that counties with larger shares of employment in farming, mining, and manufacturing have higher CVD mortality rates. The relationships between certain industry employment shares and CVD mortality rates can be partially explained by higher concentration of air pollutants, worse economic wellbeing, and fewer health care resources in counties with larger shares of employment in these industries. However, the importance of these mechanisms varies by industry. In manufacturing-dominant counties, air pollution, median household income, and physician rate help explain higher CVD mortality rates. In farming counties, median household income and physician rate are crucial. In mining counties, the physician rate is important. These findings reveal how local industry structures function as institutions that produce and exacerbate multiple place-level disadvantages and how these disadvantages contribute to CVD mortality.
Using Artificial Intelligence for Essay Writing
Authors: Jen Shirley Ling , Salam Abdul Rahim
Published: May 2024

This study hopes to bring insights for researchers and educators in using artificial intelligence for essay writing through a systematic review on the use of AI in writing for the past 10 years. Although Artificial Intelligence has long existed in other fields such as medicine, engineering, journalism, and forensic analysis, it has only made a great impact in the education field after the emergence of ChatGPT. Generative Artificial Intelligence is seen as a tool that can assist teachers and students in academics such as generating ideas, evaluating essays, storytelling, and providing feedback. It has even been considered as the co-author in students’ manuscripts and essays. However, there are still lack of studies on the usage of Artificial Intelligence in developing students’ essay writing performance. Thus, this study hopes to enlighten researchers and educators in using Artificial Intelligence tools in improving students’ essay writing performance. This study will provide insights for researchers and teachers on the different types of artificial intelligence tools that can be used in teaching essay writing. It also provides areas that researchers can focus on since majority of the studies are conducted overseas and only two studies are carried out in Malaysia so far. Hopefully, this study will provide useful information for language teachers in using artificial intelligence tools in teaching essay writing to students.
Navigating the Artificial Intelligence Frontier: Perceptions of Instructors, Students, and Administrative Staff on the Role of Artificial Intelligence in Education in the Sultanate of Oman
Authors: Syahrin Syerina , Akmal Nurul
Published: May 2024

This study examines the perceptions of instructors, students, and administrative staff on the role of ChatGPT in Oman’s educational setting. This study is significant as it provides insights into the extent to which Artificial Intelligence is used in education and provides guidance for future plans. Examining the perceptions of the various stakeholders in an education setting in Oman provides valuable information for higher learning institutions that are keen on embracing new technology while keeping to the traditional education values. The study utilized focus group discussions to gather the data from the instructors, students, and administrative staff. The findings revealed that ChatGPT’s instrumental role is in refining content, especially among students, administrative staff, and instructors who are non-native English speakers. Administrative staff and instructors highlighted its efficacy in drafting emails, indicating Artificial Intelligence’s potential to improve routine cognitive tasks. Students appreciated ChatGPT for explaining complex academic tasks. However, concerns surface from the instructors regarding over-reliance on Artificial Intelligence and potential loss of academic integrity, resonating with previous literature. These findings are contextualized within Oman’s unique socio-cultural and educational settings. Given the emergent nature of Artificial Intelligence in Oman’s education, the study offers insights that provide a foundation for future research and guide policymaking.
Citizen Scholar Chapter 7: Activism and Active Citizenship
Authors: Cohen Philip N.
Published: May 2024

For scholars who are worried that being too political in their public life will undermine their status or legitimacy as scholars, I want to urge a more open attitude toward an activist orientation, regardless of your political perspective, and help guide that choice. If we only have one identity across our various platforms and modes of communication then you can’t separate them, can’t leave your scholar identity behind. So the alternative to speaking out “as a scholar” is silence, which is not acceptable for a citizen. Meanwhile, a smaller contingent of academic scholars, including “scholar activists,” sees its scholarship as activism. In the second section, then, I argue for maintaining a distinction between different forms of speech and communication, so that your active citizenship does not in fact compromise your scholarship.
Current Strategies for Vaccine Prophylaxis of Lyme Disease
Authors: Kolyasnikova N. M. , Artamonova E. A. , Erovichenkov A. A. , Pylaeva S. K. , Belyakova A. V. , Ishmukhametov A. A.
Published: May 2024

Relevance. Lyme disease (LD) remains an important public health problem, especially in Russia, where the incidence is consistently high. To date, there is still no available vaccine against LD, and prevention involves non-specific measures. Aim: to review the literature and summarise data on progress, approaches and strategies for LD vaccine development. Conclusions. The first LD vaccines were developed in the 1990s. An OspA-based vaccine (LYMErix) was commercially available in the early 2000s but not widely distributed. An important milestone in the development of LD vaccines was the shift from the development of monovalent vaccines based on a single type of outer surface protein to the development of multivalent combinations that provide protection against different Borrelia genospecies. A multivalent OspA-based vaccine (VLA15) is in phase III clinical trials and is likely to be the next LD vaccine available on the market. New genetic strategies for vaccine development, identification of new immunogens, and development of vaccines targeting different parts of the LD transmission cycle are of broad interest for further development of LD vaccines.
National Concept of Development of Vaccine Prophylaxis in Russia
Authors: Briko N. I. , Feldblyum I. V.
Published: May 2024

The article is dedicated to outlining the conceptual directions for the development of vaccination in the Russian Federation. The provisions of the concept are formulated based on the authors' years of research on vaccination issues and analysis of data from domestic and foreign scientific literature. The main provisions of the concept aim at strengthening the state policy in the field of vaccination, reconstructing and expanding enterprises for the production of domestic vaccines, developing and improving immunobiological medicinal products against current infections, refining the National Immunization Schedule and Vaccination Schedule according to epidemiological indications; further promoting the WHO's "lifelong immunization" strategy; developing regional immunization programs; implementing a risk-oriented approach in the development of immunization programs; developing a system for monitoring post-vaccination complications; implementing epidemiological surveillance of vaccination as a methodology for assessing the strategy and tactics of immunization in accordance with the epidemiological situation; ensuring commitment to vaccination among the population, healthcare workers, and legislative and executive authorities.
Epidemiological Aspects and Basic Directions of the Protective Medications against Monkeypox Development
Authors: Stovba L. F. , Petrov A. A. , Cherniкova N. K. , Khmelev A. L. , Kuznetsov S. L. , Borisevich S. V.
Published: May 2024

Relevance. After smallpox eradication, in conditions of population immunity to orthopoxviruses absence, Monkeypox virus became most significant orthopoxvirus, pathogenic for humans. Therefore the generalization of data on the areas of infection outbreaks, human diseases and methods of prevention and treatment of monkey pox is important task. Aim. To characterize the problem of monkeypox in the world based on an analysis of foreign scientific publications over the past 20 years. Materials and methods. The work used publications presented in the main international medical information databases PubMed, Web of Science, Embase, etc. To analyze the publications, the analytical epidemiological method was used. Results and discussion. Monkeypox virus, obtained and identified in 1958, by genetic and phenotypic differences divides on two clades: West-African with lethality 3.6% and Central-African (Congo Basin) with lethality 10%. Monkeypox virus transmission to men happens in two ways, either from animal-to-human or human-to-human. Monkey pox is endemic only on African continent, but In 2003 year the first outbreak, numbering 47 confirmed cases, was occurred in non-endemic country – USA and the largest monkeypox outbreak began in Nigeria in September 2017 year and continue to the present. Comparison of the genome sequences of strains, isolated from patients in non-endemic countries, showed, that it genetically close to West-african strains, belong to II clades and were descended from a common ancestor. Many cases of disease in humans in the current outbreak have been traced to sexual transmission especially among men, who identify ourselves as gay or bisexual. The basis method for identification of agent in present time is PCR-RT targeting on the tumor necrosis factor (TNF) receptor gene. Usually monkeypox of human is mild, self-limiting disease. The symptoms of monkeypox are varied and non-specific. One of the most frequently observed clinical symptoms is lymphadenopathy. Most patients recover during some weeks. However, specific antiviral treatment – tecovirimat (S-246) and brincidofovir (CMX-001) – may be used for seriously ill or immunocompromised individuals. For prophylactic disease in present time are use vaccines JYNNEOSTM, ACAM2000R and Aventis Pasteur (APSV). Conclusion. General vaccination against monkeypox don't develop accordingly to modern recommendations WHO. Ring vaccination is recommended to conduct for suppression of spread virus in nidus of infection among population. Timely international coordination is needed to prevent the global spread of a disease with epidemic potential.
China's Role in the Indo-US Strategic Interest in the Indian Ocean Region
Authors: Arshad Muhammad Saad , Akbar Najma , Shamsuddin Syed
Published: May 2024

The strategic position and economic resources of the Indian Ocean Region (IOR) make it a point of contention for both big and regional governments. The United States and India maintain friendly diplomatic and security ties and are regarded as trustworthy strategic partners. Both countries maintained diplomatic ties throughout the Cold War, although India was the USSR's reliable strategic ally at the time. India changed its course and started bolstering its bilateral relations with the US after the Cold War ended. Both states participate in several economic and geopolitical accords. Although the United States and India both have interests in the Indian Ocean area, their interests coincide to counteract China's rise to prominence as an economic force in this region.
Unleashing Transformative Potential of Artificial Intelligence (AI) in Countering Terrorism, Online Radicalisation, Extremism, and Possible Recruitment
Authors: Irfan Muhammad , Abdulaziz Almeshal Ziyad , Anwar Muhammad
Published: May 2024

This research explores the implications of Artificial Intelligence (AI) in deciphering the multifarious manifestations of online Radicalisation, Extremism, and possible recruitment. It analyses AI's capabilities in disseminating positive representations and counter-narratives, its instrumental role in analysing positive imagery, optimising platform reach, and its pivotal contribution to global efforts to combat online extremism. However, AI's dualistic nature underscores the need for its ethical and responsible utilisation to curb extremist content effectively. It necessitates the development of balanced, nuanced, and coherent approaches, amalgamating enhanced analytical paradigms, collaborative efforts, ethical frameworks, strategic insight, and diversified applications. The formulation of such multifaceted approaches and cohesive strategies is paramount in navigating the intricate terrains of online extremism and in enhancing societal resilience against the proliferation of extremist ideologies. The study concludes that the strategic and ethical deployment of AI technologies is pivotal in reshaping digital discourse and in the collective endeavour to counterbalance extremist ideologies.
Beyond Borders: The Complexities of Israel-Palestine Antagonism in the Modern Middle East
Authors: Khan Muhammad Afaq Naveed , Ahmad Sohail , Alam Aftab
Published: May 2024

This paper offers a detailed examination of modern geopolitical dynamics in the Middle East, with a focus on the complex and continuing Israel-Palestine conflict. The paper reveals the region's dynamic terrain through an examination of new powers, shifting alliances, and the activities of important state and non-state actors. Turkey, Iran, and the Gulf States have emerged as powerful powers, threatening established power structures. The conflict's complexity is exacerbated by major entities motivated by national interests and security concerns. The theoretical framework of realism is used to understand these actors' intentions and acts. The paper seeks to provide a detailed knowledge of the Middle East's geopolitical developments by diving into historical and current factors. Despite certain limits in data dependence and conflict complexity, this study provides valuable insights into the complicated tapestry of the Israel-Palestine conflict within the larger domain of international politics.
The Threat of Transnational Terrorism: Exploring the Global and Regional Impact of Boko Haram and Al-shabab
Authors: Munir Sahibzada Adil
Published: May 2024

Al-Shabaab is an example of a transnational terrorist organisation that has grown because of intricate historical, political, and socioeconomic reasons. Even though each group has its distinct history and traits, they all share certain similar beliefs, strategies, and goals. This chapter will look at how much regional and international security is being threatened by transnational terrorist organisations like Boko Haram and Al-Shabab, the local branches of Islamic State and Al-Qaeda. This chapter emphasises the tremendous influence these organisations have on local communities, governments, and international relations by studying their backgrounds, goals, strategies, and methods of taking advantage of weaknesses and conflicts. The case studies offered provide a greater comprehension of the local and global effects of their actions.
Microscope-integrated optical coherence tomography for in vivo human brain tumor detection with artificial intelligence
Authors: Kuppler Patrick , Strenge Paul , Lange Birgit , Spahr-Hess Sonja , Draxinger Wolfgang , Hagel Christian , Theisen-Kunde Dirk , Brinkmann Ralf , Huber Robert , Tronnier Volker , Bonsanto Matteo Mario
Published: May 2024

OBJECTIVE

It has been shown that optical coherence tomography (OCT) can identify brain tumor tissue and potentially be used for intraoperative margin diagnostics. However, there is limited evidence on its use in human in vivo settings, particularly in terms of its applicability and accuracy of residual brain tumor detection (RTD). For this reason, a microscope-integrated OCT system was examined to determine in vivo feasibility of RTD after resection with automated scan analysis.

METHODS

Healthy and diseased brain was 3D scanned at the resection edge in 18 brain tumor patients and investigated for its informative value in regard to intraoperative tissue classification. Biopsies were taken at these locations and labeled by a neuropathologist for further analysis as ground truth. Optical OCT properties were obtained, compared, and used for separation with machine learning. In addition, two artificial intelligence–assisted methods were utilized for scan classification, and all approaches were examined for RTD accuracy and compared to standard techniques.

RESULTS

In vivo OCT tissue scanning was feasible and easily integrable into the surgical workflow. Measured backscattered light signal intensity, signal attenuation, and signal homogeneity were significantly distinctive in the comparison of scanned white matter to increasing levels of scanned tumor infiltration (p < 0.001) and achieved high values of accuracy (85%) for the detection of diseased brain in the tumor margin with support vector machine separation. A neuronal network approach achieved 82% accuracy and an autoencoder approach 85% accuracy in the detection of diseased brain in the tumor margin. Differentiating cortical gray matter from tumor tissue was not technically feasible in vivo.

CONCLUSIONS

In vivo OCT scanning of the human brain has been shown to contain significant value for intraoperative RTD, supporting what has previously been discussed for ex vivo OCT brain tumor scanning, with the perspective of complementing current intraoperative methods for this purpose, especially when deciding to withdraw from further resection toward the end of the surgery.
A watch, wait, and rescan approach for incidental benign-appearing notochordal lesions of the skull base
Authors: Usher Inga E. , Drosos Evangelos , Morsy Abdalla , Wadeson Andrea , Laitt Roger , Abdulla Sarah , Madhavan Aparna , Halliday Jane , Rutherford Scott , King Andrew T. , Pathmanaban Omar N.
Published: May 2024

OBJECTIVE

The aim of this study was to describe the natural history of incidental benign-appearing notochordal lesions of the skull base with specific attention to features that can make differentiation from low-grade chordoma more difficult, namely contrast uptake and bone erosion.

METHODS

In this retrospective case series, the authors describe the clinical outcomes of 58 patients with incidental benign-appearing notochordal lesions of the clivus, including those with minor radiological features of bone erosion or contrast uptake.

RESULTS

All lesions remained stable during a median follow-up of almost 3 years. Thirty-seven (64%) patients underwent contrast-enhanced MRI; lesions in 14 (38%) of these patients exhibited minimal contrast enhancement. Twenty-seven (47%) patients underwent CT; lesions in 6 (22%) of these patients exhibited minimal bone erosion.

CONCLUSIONS

These data make the case for monitoring selected cases of benign-appearing notochordal lesions of the clivus in the first instance even when there is minor contrast uptake or minimal bone erosion.
Proton versus photon adjuvant radiotherapy: a multicenter comparative evaluation of recurrence following spinal chordoma resection
Authors: Ghaith Abdul Karim , Nguyen Ryan , El-Hajj Victor Gabriel , Montaser Alaa , De Biase Gaetano , Ravindran Krishnan , Perez-Vega Carlos , Lee Seung Jin , Dominari Asmina , Battistin Umberto , Suárez-Meade Paola , Moussalem Charbel , Patel Naresh P. , Kalani Maziyar A. , Clarke Michelle J. , Rose Peter S. , Bydon Mohamad , Abode-Iyamah Kingsley , Akinduro Oluwaseun O.
Published: May 2024

OBJECTIVE

Chordomas are rare tumors of the skull base and spine believed to arise from the vestiges of the embryonic notochord. These tumors are locally aggressive and frequently recur following resection and adjuvant radiotherapy. Proton therapy has been introduced as a tissue-sparing option because of the higher level of precision that proton-beam techniques offer compared with traditional photon radiotherapy. This study aimed to compare recurrence in patients with chordomas receiving proton versus photon radiotherapy following resection by applying tree-based machine learning models.

METHODS

The clinical records of all patients treated with resection followed by adjuvant proton or photon radiotherapy for chordoma at Mayo Clinic were reviewed. Patient demographics, type of surgery and radiotherapy, tumor recurrence, and other variables were extracted. Decision tree classifiers were trained and tested to predict long-term recurrence based on unseen data using an 80/20 split.

RESULTS

Fifty-three patients with a mean ± SD age of 55.2 ± 13.4 years receiving surgery and adjuvant proton or photon therapy to treat chordoma were identified; most patients were male. Gross-total resection was achieved in 54.7% of cases. Proton therapy was the most common adjuvant radiotherapy (84.9%), followed by conventional or external-beam radiation therapy (9.4%) and stereotactic radiosurgery (5.7%). Patients receiving proton therapy exhibited a 40% likelihood of having recurrence, significantly lower than the 88% likelihood observed in those treated with nonproton therapy. This was confirmed on logistic regression analysis adjusted for extent of tumor resection and tumor location, which revealed that proton adjuvant radiotherapy was associated with a decreased risk of recurrence (OR 0.1, 95% CI 0.01–0.71; p = 0.047) compared with photon therapy. The decision tree algorithm predicted recurrence with an accuracy of 90% (95% CI 55.5%–99.8%), with the lowest risk of recurrence observed in patients receiving gross-total resection with adjuvant proton therapy (23%).

CONCLUSIONS

Following resection, adjuvant proton therapy was associated with a lower risk of chordoma recurrence compared with photon therapy. The described machine learning models were able to predict tumor progression based on the extent of tumor resection and adjuvant radiotherapy modality used.
Quality of life in chordoma survivors: results from the Chordoma Foundation Survivorship Survey
Authors: Jimenez Adrian E. , Cicalese Kyle V. , Jimenez Miguel A. , Chakravarti Sachiv , Kuo Cathleen C. , Lozinsky Shannon , Schwab Joseph H. , Knowlton Sasha E. , Rowan Nicholas R. , Mukherjee Debraj
Published: May 2024

OBJECTIVE

Chordomas are rare malignant bone tumors whose location in the skull base or spine, invasive surgical treatment, and accompanying adjuvant radiotherapy may all lead patients to experience poor quality of life (QOL). Limited research has been conducted on specific demographic and clinical factors associated with decreased QOL in chordoma survivors. Thus, the aim of the present study was to investigate several potential variables and their impact on specific QOL domains in these patients as well the frequencies of specific QOL challenges within these domains.

METHODS

The Chordoma Foundation (CF) Survivorship Survey was electronically distributed to chordoma survivors subscribed to the CF Chordoma Connections forum. Survey questions assessed QOL in three domains: physical, emotional/cognitive, and social. The degree of impairment was assessed by grouping the participants into high- and low-challenge groups designated by having ≥ 5 or < 5 symptoms or challenges within a given QOL domain. Bivariate analysis of demographic and clinical characteristics between these groups was conducted using Fisher’s exact test and the Mann-Whitney U-test.

RESULTS

A total of 665 chordoma survivors at least partially completed the survey. On bivariate analysis, female sex was significantly associated with increased odds of significant emotional (p = 0.001) and social (p = 0.019) QOL burden. Younger survivors (age < 65 years) were significantly more likely to experience significant physical (p < 0.0001), emotional (p < 0.0001), and social (p < 0.0001) QOL burden. Skull base chordoma survivors had significantly higher emotional/cognitive QOL burden than spinal chordoma survivors (p = 0.022), while the converse was true for social QOL challenges (p = 0.0048). Survivors currently in treatment were significantly more likely to experience significant physical QOL challenges compared with survivors who completed their treatment > 10 years ago (p = 0.0074). Fear of cancer recurrence (FCR) was the most commonly reported emotional/cognitive QOL challenge (49.6%). Only 41% of the participants reported having their needs met for their physical QOL challenges as well as 25% for emotional/cognitive and 18% for social.

CONCLUSIONS

The authors’ findings suggest that younger survivors, female survivors, and survivors currently undergoing treatment for chordoma are at high risk for adverse QOL outcomes. Additionally, although nearly half of the participants reported a FCR, very few reported having adequate emotional/cognitive care. These findings may be useful in identifying specific groups of chordoma survivors vulnerable to QOL challenges and bring to light the need to expand care to meet the QOL needs for these patients.
The utility of inflammatory biomarkers in predicting overall survival and recurrence in skull base chordoma
Authors: Hoppe Meagan , Gersey Zachary C. , Muthiah Nallammai , Abdallah Hussein M. , Plute Tritan , Abou-Al-Shaar Hussam , Wang Eric W. , Snyderman Carl H. , Zenonos Georgios A. , Gardner Paul A.
Published: May 2024

OBJECTIVE

Numerous studies have investigated the impact of inflammatory factors in cancer, yet few attempts have been made to investigate these markers in skull base chordoma (SBC). Inflammatory values including neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), lymphocyte-monocyte ratio (LMR), systemic immune inflammation index (SII), and systemic inflammation response index (SIRI) can serve as prognostic markers in various cancers. This study aimed to determine whether these inflammatory factors influence overall survival (OS) or progression-free survival (PFS) in patients with primary SBC.

METHODS

The electronic medical records of patients with primary SBC who underwent resection from 2001 to 2020 were retrospectively reviewed for the associations of sex, age at diagnosis, preoperative steroid use, tumor volume, extent of resection, adjuvant radiation after surgery, tumor metastasis, Ki-67 index, percent homozygous deletion of 9p23 and percent 1p36 loss, and potential prognostic inflammatory markers of NLR, PLR, LMR, SII, and SIRI with the primary outcome measures of OS and PFS. Maximum log-rank statistical tests were used to determine inflammatory marker thresholds for grouping prior to Kaplan-Meier and Cox proportional hazards analysis for OS and PFS of the elucidated groups.

RESULTS

The cohort included 115 primary SBC patients. The mean ± SD tumor volume was 23.0 ± 28.0 cm3, 73% of patients received gross-total resection, 40% received postoperative radiation, 25% had local recurrence, and 6% had subsequent metastatic disease (mean follow-up 47.2 months). Univariable Cox analysis revealed that NLR (p < 0.01), PLR (p = 0.04), LMR (p = 0.04), SII (p < 0.01), and SIRI (p < 0.01) were independently associated with PFS. Additionally, NLR (p = 0.05) and SII (p = 0.03) were significant in multivariable Cox analysis of PFS. However, both univariable and multivariable Cox analysis revealed no correlations with OS.

CONCLUSIONS

The routine assessment of inflammatory biomarkers such as NLR and SIRI could have prognostic value in postresection SBC patients.
Stereotactic radiosurgery in the management of skull base chordomas: a comprehensive systematic review and meta-analysis
Authors: Maroufi Seyed Farzad , Fallahi Mohammad Sadegh , Sabahi Mohammadmahdi , Maroufi Seyede Parmis , Sheehan Jason P.
Published: May 2024

OBJECTIVE

Chordoma is a primary bone tumor with limited literature on its management because of its rarity. Resection, while considered the first-line treatment, does not always provide adequate tumor control. In this systematic review, the authors aimed to provide comprehensive insights by managing these tumors with stereotactic radiosurgery (SRS).

METHODS

A systematic review was conducted according to PRISMA guidelines using the PubMed, Scopus, Web of Science, Embase, and Cochrane Library databases. Search terms included chordoma and radiosurgery and their equivalent terms. Data on baseline characteristics, SRS details, and outcomes were extracted. The Joanna Briggs Institute checklist was used to assess risk of bias. A meta-analysis was performed on relevant variables.

RESULTS

A total of 33 eligible studies encompassing 714 patients with skull base chordomas were included. Most studies had a low risk of bias. Patients, predominantly male (57.37%) with a mean age of 46.54 years, exhibited a conventional chordoma subtype (74.77%) and primary lesions (77.91%), mainly in the clivus (98.04%). The mean lesion volume was 13.49 cm3, and 96.68% of patients had undergone prior surgical attempts. Gamma Knife radiosurgery (88.76%) was the predominant SRS method. Radiologically, 27.19% of patients experienced tumor regression, while 55.02% showed no signs of disease progression at the latest follow-up. Progression occurred after a mean of 48.02 months. Symptom improvement was noted in 27.98% of patients. Radiosurgery was associated with a relatively low overall adverse event rate (11.94%), mainly cranial nerve deficits (8.72%). Meta-regression revealed that age and primary lesion type influenced symptom improvement, while factors like extent of resection, radiotherapy, and SRS type affected adverse event rates.

CONCLUSIONS

This systematic review provides evidence on the safety and effectiveness of radiosurgery in the management of skull base chordomas. Local tumor control was achieved in the majority of patients treated with SRS. Various baseline characteristics and SRS features have been analyzed to identify modifying factors for each outcome to provide a framework for informed decision-making when managing these patients.
Evaluation of the Glasgow Coma Scale–Pupils score for predicting inpatient mortality among patients with traumatic subdural hematoma at United States trauma centers
Authors: Ran Kathleen R. , Alfonzo Horowitz Melanie , Liu Jiaqi , Vattipally Vikas N. , Dardick Joseph M. , Williams John R. , Rincon-Torroella Jordina , Xu Risheng , Mukherjee Debraj , Haut Elliott R. , Suarez Jose I. , Huang Judy , Bettegowda Chetan , Azad Tej D. , Byrne James P.
Published: May 2024

OBJECTIVE

The Glasgow Coma Scale–Pupils (GCS-P) score has been suggested to better predict patient outcomes compared with GCS alone, while avoiding the need for more complex clinical models. This study aimed to compare the prognostic ability of GCS-P versus GCS in a national cohort of traumatic subdural hematoma (SDH) patients.

METHODS

Patient data were obtained from the National Trauma Data Bank (2017–2019). Inclusion criteria were traumatic SDH diagnosis with available data on presenting GCS score, pupillary reactivity, and discharge disposition. Patients with severe polytrauma or nonsurvivable head injury at presentation were excluded. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) of GCS-P versus GCS scores for inpatient mortality prediction were evaluated across the entire cohort, as well as in subgroups based on age and traumatic brain injury (TBI) type (blunt vs penetrating). Calibration curves were plotted based on predicted probabilities and actual outcomes.

RESULTS

A total of 196,747 traumatic SDH patients met the study inclusion criteria. Sensitivity (0.707 vs 0.702), specificity (0.821 vs 0.823), and AUC (0.825 vs 0.814, p < 0.001) of GCS-P versus GCS scores for prediction of inpatient mortality were similar. Calibration curve analysis revealed that GCS scores slightly underestimated inpatient mortality risk, whereas GCS-P scores did not. In patients > 65 years of age with blunt TBI (51.9%, n = 102,148), both GCS-P and GCS scores underestimated inpatient mortality risk. In patients with penetrating TBI (2.4%, n = 4,710), the AUC of the GCS-P score was significantly higher (0.902 vs 0.851, p < 0.001). In this subgroup, both GCS-P and GCS scores underestimated inpatient mortality risk among patients with lower rates of observed mortality and overestimated risk among patients with higher rates of observed mortality. This effect was more pronounced in the GCS-P calibration curve.

CONCLUSIONS

The GCS-P score provides better short-term prognostication compared with the GCS score alone among traumatic SDH patients with penetrating TBI. The GCS-P score overestimates inpatient mortality risk among penetrating TBI patients with higher rates of observed mortality. For penetrating TBI patients, which comprised 2.4% of our SDH cohort, a low GCS-P score should not justify clinical nihilism or forgoing aggressive treatment.
Analysis of neurosurgery resident research activity in the United States
Authors: Vought Rita , Vought Victoria , Sames Antonia , Shah Shrey , Bosland Amanda , Petrozzino Marco , Herzog Ava , Liu James K.
Published: May 2024

OBJECTIVE

Evaluation of the demographic and academic characteristics of current neurosurgery residents may provide prospective students with insight into factors that affect research output. Therefore, this study aimed to evaluate the research output among neurosurgery residents.

METHODS

US neurosurgery residency programs were abstracted from the American Association of Neurological Surgeons website. Demographic data on 1690 current residents across 119 programs were collected using publicly available institutional websites, Doximity, and LinkedIn. The h-index of each resident was recorded using Scopus and exported into the NIH iCite tool to determine the weighted relative citation ratio (w-RCR) and mean relative citation ratio (m-RCR). The total number of publications, h-index, and w-RCR were used as a proxy for research output, while m-RCR was used to measure research impact. One-way ANOVA and Kruskal-Wallis H-tests were used to assess the statistical significance of relationships between demographic data and measures of research activity.

RESULTS

A total of 1690 residents (25.4% female), representing 119 programs, were evaluated. Neurosurgery residents had an average of 17 publications, h-index of 5.5, m-RCR of 1.4, and w-RCR of 16.9, with an upward trend of research activity by postgraduate year (PGY) class. Male residents on average had a greater total number of publications (p < 0.001), higher h-index (p < 0.001), and higher w-RCR (p = 0.002) compared with their female peers. Significant differences in research activity were also observed by degree (Doctor of Medicine [MD], Doctor of Osteopathy [DO], or other), where those with MD and other degrees had higher metrics than those with DO degrees. International medical graduates (IMGs) also had higher research output than American medical graduates (AMGs) (p < 0.001). Differences in all measures of research activity except impact were also observed in research activity when pre-residency medical school ranks were compared.

CONCLUSIONS

The authors observed overall high research activity among neurosurgery residents. Factors such as gender, degree, PGY, IMG/AMG status, and medical school rank may therefore be related to the success of matching within neurological surgery. Although large disparities in gender representation have been identified in neurosurgery, newer classes are trending toward shrinking the gap. These data may be used by prospective residents to gauge changes and progress occurring in the neurosurgery match.
C1–2 hypermobility and its impact on the spinal cord: a finite element analysis
Authors: Patel Arpan A. , Greenberg Jacob K. , Steinmetz Michael P. , Vorster Sarel , Nevzati Edin , Spiessberger Alexander
Published: May 2024

OBJECTIVE

The authors present a finite element analysis (FEA) evaluating the mechanical impact of C1–2 hypermobility on the spinal cord.

METHODS

The Code_Aster program was used to perform an FEA to determine the mechanical impact of C1–2 hypermobility on the spinal cord. Normative values of Young’s modulus were applied to the various components of the model, including bone, ligaments, and gray and white matter. Two models were created: 25° and 50° of C1-on-C2 rotation, and 2.5 and 5 mm of C1-on-C2 lateral translation. Maximum von Mises stress (VMS) throughout the cervicomedullary junction was calculated and analyzed.

RESULTS

The FEA model of 2.5 mm lateral translation of C1 on C2 revealed maximum VMS for gray and white matter of 0.041 and 0.097 MPa, respectively. In the 5-mm translation model, the maximum VMS for gray and white matter was 0.069 and 0.162 MPa. The FEA model of 25° of C1-on-C2 rotation revealed maximum VMS for gray and white matter of 0.052 and 0.123 MPa. In the 50° rotation model, the maximum VMS for gray and white matter was 0.113 and 0.264 MPa.

CONCLUSIONS

This FEA revealed significant spinal cord stress during pathological rotation (50°) and lateral translation (5 mm) consistent with values found during severe spinal cord compression and in patients with myelopathy. While this finite element model requires oversimplification of the atlantoaxial joint, the study provides biomechanical evidence that hypermobility within the C1–2 joint leads to pathological spinal cord stress.